JP6459255B2 - Rotary compressor - Google Patents

Description

  The present invention provides a cylinder, a piston that rotates eccentrically in the cylinder, and an annular cylinder chamber that is divided into a plurality of sections from the inner peripheral side to the outer peripheral side between the piston and the cylinder. The present invention relates to a rotary compressor provided with a compression mechanism having a partitioning blade.

  Conventionally, a rotary compressor has been proposed in which a plurality of annular cylinder chambers are partitioned from the inner peripheral side to the outer peripheral side of the compression mechanism by arranging an annular piston inside the annular cylinder chamber of the cylinder. (For example, refer to Patent Document 1). In the compression mechanism of the compressor of Patent Document 1, four cylinder chambers are formed between the cylinder and the piston. The rotary compressor is configured to compress the refrigerant in four stages in the four cylinder chambers. This compressor is provided in a refrigerant circuit of a refrigeration apparatus such as an air conditioner.

  Specifically, in the compression mechanism, four chambers are formed by three cylinder chambers formed on the upper surface side of the end plate of the annular piston and one cylinder chamber formed on the outer peripheral surface side of the end plate. A cylinder chamber is formed. In the compression mechanism, the outermost cylinder chamber is the first stage and the low pressure compression chamber, the innermost cylinder chamber is the fourth stage and the high pressure compression chamber, and the middle two cylinder chambers are the second. The stage and the third stage are compression chambers of intermediate pressure. This compression mechanism is provided with a blade formed so as to partition these four compression chambers into a high pressure side and a low pressure side.

  As shown in FIGS. 15A and 15B, the blade (100) includes a blade body (101) and a swing bush (102), and the swing bush (102) is a piston (103). ). In addition, the blade (100) has a different axial height of the compression mechanism between the radially inner end and the radially outer end, and the radially outer end height dimension (H2) is the radially inner end. It is formed larger than the height dimension (H1).

JP 2013-139729 A

  In the compression mechanism, the back pressure space (104) is formed on the back side of the blade (100) (the radially outer peripheral side of the cylinder chamber). Although not shown, an oil reservoir for storing high-pressure lubricating oil (refrigeration oil) is provided at the bottom of the casing of the compression mechanism, and a high pressure is supplied from the oil reservoir to the back pressure space (104). The lubricating oil is supplied. Then, lubricating oil is supplied from the back pressure space (104) around the blade (100) to lubricate the blade (100). Therefore, a high pressure acts on the back surface (100c) of the blade (100).

  On the other hand, high pressure pressure acts on the first end (blade inner end) (100a) of the blade (100) that defines the fourth-stage compression chamber on the innermost peripheral side, and the first-stage compression chamber on the outermost peripheral side is Low pressure pressure acts on the second end (blade outer end) (100b) of the blade (100) to be partitioned. In the compression mechanism of Patent Document 1, the first end portion (100a) and the second end portion (100b) are not in contact with the piston (a slight gap is formed between the piston and the piston). The dimensions are configured.

  In the above configuration, the height dimension (H2) of the radially outer end of the blade (100) is larger than the height dimension (H1) of the radially inner end, and the radially inner end and the radially outer end of the blade (100). Since a high pressure is desired to act on both ends, the pressing load acting from the radially outer side to the radially inner side increases as shown by the arrow in FIG. In the above configuration, since the pressing load is received only by the bushing hole (105) of the piston, the surface pressure of the swinging bush portion supporting the load in FIG. In this case, seizure of the swinging bush portion (102) occurred, and the reliability of the compression mechanism might be lowered.

  In addition, the tip of the blade (100) (the blade inner end (100a) which is the first end and the blade outer end “(100b) which is the second end) is not in contact with the piston (106) ( For this reason, there is a risk that the volumetric efficiency is reduced due to the loss caused by the refrigerant leaking from the high pressure side to the low pressure side of the cylinder chamber, and the performance of the compressor is lowered.

  The present invention has been made in view of such problems, and an object of the present invention is to define an annular cylinder chamber formed in a plurality of sections from an inner peripheral side to an outer peripheral side between a piston and a cylinder as a high pressure side. In a rotary compressor equipped with a blade that partitions on the low pressure side, the seizure of the swing bushing and the leakage of refrigerant from the high pressure side to the low pressure side of the cylinder chamber are suppressed. Is to be able to.

The first invention includes a cylinder (21, 31), a piston (22, 32) that rotates eccentrically in the cylinder (21, 31), the cylinder (21, 31), and the piston (22, 32). And a compression mechanism (40) having a high pressure chamber and a blade (24, 34) dividing the cylinder chamber (23a, ..., 23d, 33a, ..., 33d) formed between The mechanism (40) has a blade back pressure space (21g, 31g) that applies pressure inward in the radial direction to the blade (24, 34), and the piston (22, 32) has a cylinder chamber (23a, ..., 23d, 33a,..., 33d) are divided into a plurality of cylinder chambers (23a,..., 23d, 33a,..., 33d) from the inner peripheral side to the outer peripheral side, and ring-shaped piston portions (22b, 32b); Inner circumferential piston portions (22a, 32a) located on the inner circumferential side of the ring-shaped piston portions (22b, 32b) and outer circumferential piston portions (22c, 32b) located on the outer circumferential side of the ring-shaped piston portions (22b, 32b) 32c) And the blades (24, 34) are connected to the ring-shaped piston portions (22b, 32b) so as to be swingable, and the inner peripheral piston portions (22a, 32a) ) Is an integral member having a blade inner end (24d, 34d) opposed to the outer side in the radial direction and a blade outer end (24e, 34e) opposed to the outer piston portion (22c, 32c) from the outer side in the radial direction. It is based on a compressor.

In the rotary compressor, the piston (22, 32) and the blade (24, 34) have an opposed portion between the inner peripheral side piston portion (22a, 32a) and the blade inner end (24d, 34d), It is formed so as to come into contact with at least one of the opposed portions of the outer peripheral side piston portion (22c, 32c) and the blade outer end (24e, 34e) and the connecting portion of the swinging bush portion (24c, 34c) . It is characterized by that.

  In the first invention, the blades (24, 34) and the pistons (22, 32) in which the swing bush portions (24c, 34c) are swingably connected to the ring-shaped piston portions (22b, 32b) are provided with the swing. A facing portion between the inner peripheral piston portion (22a, 32a) located on the inner peripheral side of the dynamic bush portion (24c, 34c) and the blade inner end (24d, 34d), an outer peripheral piston portion (22c, 32c), At least one of the opposed portions to the blade outer ends (24e, 34e) contacts each other. The blade (24, 34) is subjected to radially inward pressure by the blade back pressure space (21g, 31g), so that a radially inward pressing force is generated, but the blade (24, 34) and piston (22) , 32) abut the blade at least at two locations (the connecting portion of the swinging bush (24c, 34c) and the blade outer end (24e, 34e) and the blade inner end (24d, 34d)). The pressing load at the contact portion between (24, 34) and the piston (22, 32) is dispersed.

According to a second invention, in the first invention, the blade outer end (24e, 34e) and the outer peripheral piston portion (22c, 32c) are formed to contact each other, and the blade outer end (24e, 34e) The outer peripheral piston portions (22c, 32c) are characterized in that they are formed by arcuate curved surfaces having the same diameter and the same trajectory of the swinging movement of the blade outer ends (24e, 34e).

In the second aspect of the invention, the blade outer end (24e, 34e) and the outer peripheral piston portion (22c, 32c) have the same arc shape with the same trajectory and diameter as the swinging movement of the blade outer end (24e, 34e) . Since they are formed with curved surfaces and come into contact with each other, it is possible to more reliably disperse the pressing load on the outer peripheral side piston portions (22c, 32c).

According to a third invention, in the first or second invention, the blade inner end (24d, 34d) and the inner peripheral piston portion (22a, 32a) are in contact with each other, and the blade inner end (24d) , 34d) and the inner circumferential side piston portion (22a, 32a) are characterized by being formed by a curved surface having the same arc shape as the trajectory of the swinging motion of the blade inner end (24d, 34d). .

In the third aspect of the invention, the blade inner end (24d, 34d) and the inner peripheral piston portion (22a, 32a) have the same arc shape with the same trajectory and diameter as the swinging movement of the blade inner end (24d, 34d). Since the curved surfaces are in contact with each other, the pressing load on the inner peripheral side piston portions (22a, 32a) can be more reliably dispersed.

  According to a fourth invention, in any one of the first to third inventions, the compression mechanism (40) includes an innermost cylinder chamber (23a, 33a) in order from a radially inner side to a radially outer side. It has four cylinder chambers (23a, ..., 23d, 33a, ..., 33d), an inner cylinder chamber (23b, 33b), an outer cylinder chamber (23c, 33c) and an outermost cylinder chamber (23d, 33d), The blade inner end (24d, 34d) is disposed in the innermost cylinder chamber (23a, 33a), and the blade outer end (24e, 34e) is disposed in the outermost cylinder chamber (23d, 33d). Yes.

  In the fourth aspect of the invention, the innermost cylinder (21, 31) of the compression mechanism (40) having four cylinder chambers (23a, ..., 23d, 33a, ..., 33d) is disposed at the blade inner end (24d, 34d). In the configuration in which the outermost cylinder chamber (23d, 33d) is partitioned into the high pressure side and the low pressure side at the blade outer end (24e, 34e), the blade (24, 34) and the piston (22, 32) abuts at least at two locations, so that the pressing load at the contact portion between the blade (24, 34) and the piston (22, 32) is dispersed.

  According to the present invention, the blade (24, 34) and the piston (22, 32) have at least two locations (the connecting portion of the swinging bush portion (24c, 34c), the blade outer end (24e, 34e), and the blade inner side. At the end (at least one of 24d, 34d), and the pressing load at the contact portion between the blade (24, 34) and the piston (22, 32) is dispersed. , 34c) to prevent seizure in the compressor and reduce the reliability of the compressor, and also due to refrigerant leakage from the high pressure side to the low pressure side of the cylinder chamber (23a, ..., 23d, 33a, ..., 33d) The deterioration of the compressor performance is also suppressed.

According to the second aspect of the invention, the blade outer end (24e, 34e) and the outer peripheral side piston portion (22c, 32c) are made to have an arc having the same radial dimension as the locus of the swinging motion of the blade outer end (24e, 34e). Since the curved surfaces are formed so as to be in contact with each other, the pressing load on the outer peripheral side piston portions (22c, 32c) can be more reliably dispersed. Therefore, seizure in the swinging bush (24c, 34c) is suppressed to prevent the compressor from being lowered in reliability, and the low pressure from the high pressure side of the cylinder chamber (23a, ..., 23d, 33a, ..., 33d). A decrease in the performance of the compressor due to refrigerant leakage to the side is also suppressed.

According to the third aspect of the present invention, the blade inner end (24d, 34d) and the inner peripheral side piston portion (22a, 32a) have the same trajectory and radial dimension as the blade inner end (24d, 34d). Since they are formed so as to be in contact with each other by being formed with arcuate curved surfaces , it is possible to more reliably disperse the pressing load on the inner circumferential side piston portions (22a, 32a). Therefore, seizure in the swinging bush (24c, 34c) is suppressed to prevent the compressor from being lowered in reliability, and the low pressure from the high pressure side of the cylinder chamber (23a, ..., 23d, 33a, ..., 33d). A decrease in the performance of the compressor due to refrigerant leakage to the side is also suppressed.

  According to the fourth aspect of the invention, in the compression mechanism (40) having the four cylinder chambers (23a, ..., 23d, 33a, ..., 33d), the blades (24, 34) and the pistons (22, 32) Abuts at least at two locations so that the pressing load at the contact portion between the blade (24, 34) and the piston (22, 32) is dispersed, so that seizure at the rocking bush portion (24c, 34c) is suppressed. This reduces the reliability of the compressor and reduces the performance of the compressor due to refrigerant leakage from the high pressure side to the low pressure side of the cylinder chamber (23a, ..., 23d, 33a, ..., 33d). Is also suppressed.

FIG. 1 is a longitudinal sectional view of a rotary compressor according to an embodiment of the present invention. FIG. 2 is an enlarged view around the compression mechanism in FIG. 3A is a cross-sectional view of the compression mechanism section, and FIG. 3B is another cross-sectional view of the compression mechanism section. FIG. 4 is a perspective view of the blade. FIG. 5 is a partially enlarged view of the compression mechanism section. FIG. 6 is an operation state diagram of the compression mechanism section. FIG. 7 is an operation state diagram of the compression mechanism section. FIG. 8 is a cross-sectional view of the main body of the middle plate. FIG. 9 is an enlarged longitudinal sectional view of the compression mechanism. FIG. 10 is a ph diagram showing the refrigeration cycle during the cooling operation. FIG. 11 shows a modified example of the blade and the piston. FIG. 11A shows the shape of the portion where the blade inner end and the inner peripheral piston portion face each other, and FIG. 11B shows the blade outer end and the outer peripheral side. The shape of the part which a piston part opposes is shown. FIG. 12 is a perspective view showing a modification of the blade. FIG. 13 is a perspective view showing a reference technique of the blade. FIG. 14 is a perspective view showing another reference technique of the blade. 15A and 15B are diagrams showing the action of the pressure in the blade back pressure space in the conventional compression mechanism, FIG. 15A is a plan view, and FIG. 15B is a side view.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Overall structure>
The compressor (1) which concerns on embodiment is a rotary compressor, and as shown in FIG. 1, in a casing (10), two compression mechanism parts (a 1st compression mechanism part (20) and a 2nd compression mechanism) The compression mechanism (40) in which the portion (30) is stacked in the axial direction of the drive shaft (53) and the electric motor (50) as the drive mechanism are housed, and is configured as a completely sealed type. This compressor (1) is used, for example, in a refrigerant circuit of an air conditioner to compress refrigerant (working fluid) sucked from an evaporator and discharge it to a condenser. A middle plate (25) described later is disposed between the first compression mechanism (20) and the second compression mechanism (30).

  The casing (10) includes a cylindrical body (11), an upper end plate (12) fixed to the upper end of the body (11), and a lower part fixed to the lower end of the body (11). End plate (13). In order to guide the refrigerant to the cylinder chambers (23a,..., 23d, 33a,..., 33d) of the first compression mechanism section (20) and the second compression mechanism section (30), the details of which will be described later. Suction pipe (60, 61, 62, 63) and a discharge pipe (64, 65, 66) for discharging the refrigerant compressed in the cylinder chamber (23b, 23c, 23d, 33b, 33c, 33d) It is provided through. The upper end plate (12) is also provided with a discharge pipe (67) for discharging the refrigerant compressed in the cylinder chambers (23a, 33a). An oil reservoir (10a) for storing lubricating oil (refrigeration oil) is formed at the bottom of the casing (10).

  The electric motor (50) is disposed near the upper end plate (12) in the casing (10). The electric motor (50) includes a stator (51), a rotor (52), and a drive shaft (53). The stator (51) is fixed to the inner peripheral surface of the body (11) of the casing (10). On the other hand, the drive shaft (53) is connected to the rotor (52) so as to rotate integrally.

  The drive shaft (53) extends downward from the rotor (52), and a first eccentric part (53a) and a second eccentric part (53b) are formed in the lower part. The first eccentric portion (53a) is formed to have a larger diameter than the main shaft portion above the first eccentric portion (53a), and is eccentric by a predetermined amount from the axis of the drive shaft (53). On the other hand, the second eccentric portion (53b) is formed to have the same diameter as the first eccentric portion (53a), and is eccentric from the axis of the drive shaft (53) by the same amount as the first eccentric portion (53a). The first eccentric portion (53a) and the second eccentric portion (53b) are 180 ° out of phase with each other about the axis of the drive shaft (53).

  The first compression mechanism portion (20) and the second compression mechanism portion (30) are disposed below the electric motor (50) in the casing (10). The first compression mechanism section (20) and the second compression mechanism section (30) are stacked in two upper and lower stages, and are configured between the front head (14) and the rear head (17) fixed to the casing (10). Has been. The first compression mechanism (20) is disposed on the electric motor (50) side (upper side in FIG. 1), and the second compression mechanism (30) is disposed on the bottom side (lower side in FIG. 1) of the casing (10). ing. A muffler member (27) for forming a muffler space (27a) between the front head (14) and the upper surface of the front head (14) is attached to the upper side of the front head (14).

The first cylinder (21) includes a cylindrical cylinder body (21c) that forms a cylinder space (S1) therein and opens vertically, and a head that closes the upper opening of the cylinder body (21c). A front head (14) as a part, a plurality of cylinder parts (21a, 21b, 21c) formed in an annular shape and concentrically with the rotating shaft of the drive shaft (53), and the cylinder body part (21c) And the middle plate (25) disposed in the lower opening.
<First compression mechanism>
As shown in FIGS. 2 to 5, the first compression mechanism (20) includes a first cylinder (21) fixed to the inner peripheral surface of the body (11) of the casing (10), and a drive shaft (53 ) Of the first piston (22) attached to the first eccentric portion (53a) and rotating eccentrically with respect to the first cylinder (21), and the first cylinder (21) and the first piston (22) A first blade (4) that divides four cylinder chambers (23a, 23b, 23c, 23d) formed between them into a high pressure chamber (23aH, 23bH, 23cH, 23dH) and a low pressure chamber (23aL, 23bL, 23cL, 23dL) 24) and.

  The first cylinder (21) includes a cylindrical cylinder body (21c) that forms a cylinder space (S1) therein and opens vertically, and a head that closes the upper opening of the cylinder body (21c). A front head (14) as a part, a plurality of cylinder parts (21a, 21b, 21c) formed in an annular shape and concentrically with the rotating shaft of the drive shaft (53), and the cylinder body part (21c) And the middle plate (25) disposed in the lower opening.

  The cylinder space-side front head (15) includes a closing portion (15a) formed in a disc shape covering the upper opening of the cylinder body (21c). The cylinder space side front head (15) is formed integrally with the cylinder body (21c). A through hole (15b) through which the drive shaft (53) is inserted is formed in the central portion of the blocking portion (15a). The through hole (15b) is formed to have a slightly larger diameter than the drive shaft (53).

  The bearing portion-side front head (16) is formed separately from the cylinder space-side front head (15), and is disposed above the cylinder space-side front head (15). The bearing portion-side front head (16) includes a disk-shaped laminated portion (16a) that is superimposed on the upper surface of the cylinder space-side front head (15), and a bearing portion (16b) that is formed integrally with the laminated portion (16a). ). A through hole (16c) through which the drive shaft (53) is inserted is formed at the center of the stacked portion (16a). The bearing portion (16b) is formed in a cylindrical shape extending upward from the opening end portion of the through hole (16c) of the laminated portion (16a). A cylindrical bearing metal (16d) for rotatably supporting the drive shaft (53) is inserted and fixed on the inner peripheral surface of the bearing portion (16b).

  The plurality of cylinder portions (21a, 21b, 21c) are formed integrally with the cylinder space front head (15) on the lower surface of the cylinder space front head (15). The plurality of cylinder parts include an annular inner cylinder part (21a) formed at the innermost side, an annular outer cylinder part (21b) formed radially outward from the inner cylinder part (21a), The cylindrical outermost cylinder part (21c) is located outside the outer cylinder part (21b) and extends downward from the outer peripheral part of the outer cylinder part (21b). The inner cylinder part (21a) is partly cut off from the ring (see FIG. 3A). A slide groove (21g) is formed at a parting position of the inner cylinder part (21a). The outermost cylinder part (21c) is composed of the cylinder body part (21c).

  The middle plate (25) is formed by two members arranged in the axial direction of the drive shaft (53). Specifically, the middle plate (25) overlaps the thick disc-shaped main body (25a) covering the lower opening of the cylinder main body (21c) and the lower surface of the main body (25a). And a disc-shaped lid (25b). A through hole (25c) through which the drive shaft (53) passes is formed at the center of the middle plate (25). The through hole (25c) is a hole having a slightly larger inner diameter than the diameters of the first eccentric portion (53a) and the second eccentric portion (53b) of the drive shaft (53). The middle plate (25) also constitutes a part of the second compression mechanism part (30).

  The first piston (22) is accommodated in a cylinder chamber (S1) formed inside a cylindrical cylinder body (21c). The first piston (22) is fitted to the first eccentric part (53a) and is located concentrically with the first eccentric part (53a), and the inner piston part (inner peripheral side piston part) (22a), An annular outer piston portion (ring-shaped piston portion) (22b) positioned concentrically with the inner piston portion (22a) on the outer peripheral side of the inner piston portion (22a), and the two piston portions (22a, 22b) A piston side end plate part (outer peripheral side piston part) (22c) whose outer peripheral surface is located concentrically with the inner side piston part (22a) and the outer side piston part (22b) is provided. The inner piston part (22a) is arranged inside the inner cylinder part (21a), and the outer piston part (22b) is arranged between the inner cylinder part (21a) and the outer cylinder part (21b), The end plate part (22c) is disposed inside the outermost cylinder part (21c). The inner piston portion (22a) has a notch (n1) formed on the outer peripheral surface, and the outer piston portion (22b) is partly cut off from the ring (see FIG. 3A). Further, a notch (n2) is formed in the outer peripheral portion of the piston side end plate portion (22c) (see FIG. 3B).

  As described above, the first piston (22) disposed in the cylinder space (S1) forms a plurality of cylinder chambers with the first cylinder (21). Specifically, an innermost cylinder chamber (23a) is formed between the inner piston part (22a) and the inner cylinder part (21a), and between the outer piston part (22b) and the inner cylinder part (21a). Is formed with an inner cylinder chamber (23b), an outer cylinder chamber (23c) is formed between the outer piston portion (22b) and the outer cylinder portion (21b), and the piston side end plate portion (22c) and the outermost portion An outermost cylinder chamber (23d) is formed between the cylinder portion (21c). That is, in the first compression mechanism (20), the innermost cylinder chamber (23a), the inner cylinder chamber (23b), and the outer cylinder chamber (23c) are arranged in order from the radially inner side to the radially outer side. A chamber (23d) is formed.

  Thus, the first compression mechanism portion (20) is configured to have four cylinder chambers (23a, 23b, 23c, 23d), and the outer piston portion (ring-shaped piston portion) (22b) and The inner piston part (inner peripheral side piston part) (22a) located on the inner peripheral side of the ring-shaped piston part, and the piston side end plate part (outer peripheral side piston part) (22c) located on the outer peripheral side of the ring-shaped piston part The above-described first piston (22) has a cylinder chamber (23a, ..., 23d) partitioned into a plurality of cylinder chambers from the inner peripheral side to the outer peripheral side.

<Second compression mechanism section>
The second compression mechanism section (30) is disposed below the first compression mechanism section (20). As shown in FIGS. 2 to 5, the second compression mechanism section (30) includes a second cylinder (31) fixed to the inner peripheral surface of the body section (11) of the casing (10), and a drive shaft (53 ) Of the second piston (32) attached to the second eccentric portion (53b) and rotating eccentrically with respect to the second cylinder (31), and the second cylinder (31) and the second piston (32) A second blade (4) that divides four cylinder chambers (33a, 33b, 33c, 33d) formed between them into a high pressure chamber (33aH, 33bH, 33cH, 33dH) and a low pressure chamber (33aL, 33bL, 33cL, 33dL) 34).

  The second cylinder (31) forms a cylinder space (S2) therein and closes the cylindrical cylinder body (31c) that opens in the vertical direction and the lower opening of the cylinder body (31c). A rear head (17) as a head portion, a plurality of cylinder portions (31a, 31b, 31c) which are formed in an annular shape and concentrically with the rotation shaft of the drive shaft (53), and the cylinder body portion (31c) A middle plate (25) disposed in the upper opening.

  The rear head (17) includes a cylinder space side rear head (18) as a cylinder space side head portion and a bearing portion side rear head (19) as a bearing portion side head portion.

  The cylinder space side rear head (18) includes a closing portion (18a) formed in a disk shape covering the lower opening of the cylinder body (31c). The cylinder space side rear head (18) is formed integrally with the cylinder body (31c). A through hole (18b) through which the drive shaft (53) is inserted is formed in the central portion of the blocking portion (18a). The through hole (18b) is formed to have a slightly larger diameter than the drive shaft (53).

  The bearing portion side rear head (19) is formed separately from the cylinder space side rear head (18), and is disposed below the cylinder space side rear head (18). The bearing portion side rear head (19) includes a disk-shaped laminated portion (19a) that is stacked on the lower surface of the cylinder space side rear head (18), and a bearing portion (19b) that is formed integrally with the laminated portion (19a). It has. A through hole (19c) through which the drive shaft (53) is inserted is formed at the center of the stacked portion (19a). The bearing portion (19b) is formed in a cylindrical shape extending downward from the opening end portion of the through hole (19c) of the laminated portion (19a). A cylindrical bearing metal (19d) for rotatably supporting the drive shaft (53) is inserted and fixed on the inner peripheral surface of the bearing portion (19b).

  The plurality of cylinder portions (31a, 31b, 31c) are formed integrally with the cylinder space side rear head (18) on the upper surface of the cylinder space side rear head (18). The plurality of cylinder parts include an annular inner cylinder part (31a) formed at the innermost side, an annular outer cylinder part (31b) formed radially outward from the inner cylinder part (31a), The cylindrical outermost cylinder part (31c) is located outside the outer cylinder part (31b) and extends upward from the outer peripheral part of the outer cylinder part (31b). The inner cylinder part (31a) is partly cut off from the ring (see FIG. 3A). A slide groove (31g) is formed at a parting position of the inner cylinder part (31a). The outermost cylinder part (31c) is composed of the cylinder body part (31c).

  The second piston (32) is accommodated in a cylinder chamber (S2) formed inside the cylindrical cylinder body (31c). The second piston (32) includes an inner piston part (inner piston part) (32a) that is fitted to the second eccentric part (53b) and is concentric with the second eccentric part (53b), An annular outer piston part (ring-shaped piston part) (32b) positioned concentrically with the inner piston part (32a) on the outer peripheral side of the inner piston part (32a), and the two piston parts (32a, 32b) The upper end part is connected, and the outer peripheral surface is provided with a piston side end plate part (outer peripheral side piston part) (32c) positioned concentrically with the inner piston part (32a) and the outer piston part (32b). The inner piston part (32a) is arranged inside the inner cylinder part (31a), and the outer piston part (32b) is arranged between the inner cylinder part (31a) and the outer cylinder part (31b), The end plate part (32c) is disposed inside the outermost cylinder part (31c). The inner piston part (32a) has a notch part (n1) formed on the outer peripheral surface, and the outer piston part (32b) is partly cut off from a ring (see FIG. 3A). Further, a notch (n2) is formed in the outer peripheral portion of the piston side end plate portion (32c) (see FIG. 3B).

  As described above, the second piston (32) disposed in the cylinder space (S2) forms a plurality of cylinder chambers with the second cylinder (31). Specifically, an innermost cylinder chamber (33a) is formed between the inner piston part (32a) and the inner cylinder part (31a), and between the outer piston part (32b) and the inner cylinder part (31a). Is formed with an inner cylinder chamber (33b), an outer cylinder chamber (33c) is formed between the outer piston part (32b) and the outer cylinder part (31b), and the piston side end plate part (32c) and the outermost part. An outermost cylinder chamber (33d) is formed between the cylinder portion (31c). That is, in the second compression mechanism (30), the innermost cylinder chamber (33a), the inner cylinder chamber (33b), and the outer cylinder chamber (33c) are arranged in order from the radially inner side to the radially outer side. A chamber (33d) is formed.

  Thus, the second compression mechanism part (30) is configured to have four cylinder chambers (33a, 33b, 33c, 33d), and the outer piston part (ring-like piston part) (32b) and The inner piston part (inner peripheral side piston part) (32a) located on the inner peripheral side of the ring-shaped piston part, and the piston side end plate part (outer peripheral side piston part) (32c) located on the outer peripheral side of the ring-like piston part The second piston (32) having a plurality of cylinder chambers (33a, ..., 33d) is partitioned into a plurality of cylinder chambers from the inner peripheral side to the outer peripheral side.

  As described above, the first compression mechanism portion (20) and the second compression mechanism portion (30) are provided in the cylinder (first cylinder (21) and second cylinder (31)) and the cylinder (21, 31). Pistons (first piston (21) and second piston (22)) having end plate portions (piston side end plate portions (22c, 32c)) that are configured to be eccentrically rotatable and face the middle plate (25). And a plurality of cylinder chambers (23a, 23b) formed between the cylinder (first cylinder (21) and second cylinder (31)) and the piston (first piston (21) and second piston (22)). 23c, 23d) (33a, 33b, 33c, 33d).

<Detailed structure of compression mechanism>
Next, the internal structure of the first and second compression mechanism parts (20, 30) will be described in detail. The first and second compression mechanism parts (20, 30) have first and second pistons (22, 32). ) And the corresponding cylinder (21, 31) in the axial direction are substantially identical in configuration, so the first compression mechanism (20) will be described as a representative example. To do.

  As shown in FIGS. 4 and 5, the first blade (24) has a plate-like long part (24a) and a short part (24b) having a thickness and a pair of swings having a substantially semicircular cross section. And a bush portion (24c). These three parts (24a, 24b, 24c) are integrally formed.

  In the first blade (24), the front end portion indicated by L1 in FIG. 4 has a smaller axial dimension (height dimension) (H1) of the compression mechanism (40), and the rear end portion indicated by L2 is smaller than the front end portion. Also, the axial dimension (height dimension) (H2) of the compression mechanism (40) is set large.

  The long portion (24a) is disposed so as to extend in the radial direction between the closed portion (15a) of the cylinder space-side head portion (15) and the piston-side end plate portion (22c). The long portion (24a) includes an inner blade portion (B1) constituting a radially inner portion of the long portion (24a) and an outer first portion constituting a portion outside the inner blade portion (B1). It consists of a blade part (B2). The inner blade portion (B1) is inserted into the slide groove (21g) formed in the dividing portion of the inner cylinder portion (21a) so as to be slidable in the radial direction, and is the outer end portion of the outer first blade portion (B2). Are accommodated in a groove (slide groove) (21f) formed in the outer cylinder part (21b) so as to be slidable in the radial direction. The inner blade portion (B1) divides the innermost cylinder chamber (23a) and the inner cylinder chamber (23b) into a suction side and a discharge side, respectively, and the outer first blade portion (B2) separates the outer cylinder chamber ( 23c) is divided into a suction side and a discharge side. The first piston (22) and the first blade (24) include an outer peripheral surface of a notch (n1) of the inner piston part (22a) (inner peripheral piston part) and an inner end part of the inner blade part (B1). The opposite portions to the blade inner end (24d) are in contact with each other (see FIG. 5).

  The short part (24b) is disposed so as to extend in the radial direction between the long part (24a) and the middle plate (25). The short part (24b) is composed of an outer second blade part (B3). The radially outer portion of the short portion (24b) is accommodated in a groove (slide groove) (21f) formed in the outermost cylinder portion (21c) so as to be slidable in the radial direction. The shortest portion (24b) divides an outermost cylinder chamber (23d), which will be described later, into a suction side and a discharge side. In the piston and blade, the facing part between the notch part (n2) of the piston side end plate part (22c) (outer peripheral side piston part) and the blade outer end (24e) which is the inner end of the short part (24b) contacts each other. (See FIG. 5).

  The pair of swinging bush portions (24c) is formed so as to bulge on both sides of the long portion (24a) in the vicinity of the central portion in the longitudinal direction of the long portion (24a). The outer peripheral surfaces of the pair of swing bush portions (24c) constitute a part of the outer peripheral surface of a cylinder having a predetermined radius. The pair of swinging bush portions (24c) is swingably accommodated in bush grooves (C1, C2) formed at the parting points of the outer piston portion (22b). The pair of swing bush portions (24c) is configured such that the outer piston portion (22b) swings with respect to the first blade (24).

  As shown in FIG. 5, on the rear end side of the groove (21f), pressure is applied to the first blade (24) from the rear end surface, so that the first blade (24) is compressed by the compression mechanism (40). A first blade back pressure space (21g) for urging toward the center of the first blade is formed. Due to the pressure in the first blade back pressure space (21g), the tip end side of the blade (24) on the outer surface of the swinging bush portion (24c) comes into pressure contact with the inner surface of the bush groove (C1, C2). Also, the inner end of the inner blade (B1) (blade inner end (24d)) is in pressure contact with the notch (n1) of the inner piston (22a) (inner piston), and the short part (24b) The inner end (blade outer end (24e)) is in pressure contact with the notch (n2) of the piston side end plate (22c) (outer peripheral side piston).

  In FIG. 5, the notch (n1) constitutes a first swing allowing surface that allows the relative swinging motion of the inner blade portion (B1) with the swing bushing portion (24c) as the center. The first swing allowable surface (n1) is formed in an arc shape having the same diameter as the locus of the relative swing operation of the inner blade part (B1) with the swing bush part (24c) as the center. When the blade portion (B1) swings, the tip of the blade portion slides on the first swing allowable surface (n1).

  Further, the notch (n2) constitutes a second swing allowing surface that allows the relative swing operation of the outer second blade portion (B3) with the swing bush portion (24c) as a center. The second rocking permissible surface (n2) is formed in an arc shape having the same diameter as the locus of the relative rocking motion of the outer second blade part (B3) with the rocking bush part (24c) as the center. When the outer second blade portion (B3) swings, its tip slides with the second swing allowable surface (n2).

  With the configuration as described above, the first piston (22) has the center point of the pair of swing bush portions (24c) with respect to the first blade (24) as the first eccentric portion (53a) rotates eccentrically. Oscillates around the center of the oscillating center, and advances and retracts in the same direction as the first blade (24) slides in the longitudinal direction with respect to the groove (21f) and the slide groove (21g) of the inner cylinder part (21a). To do.

  The inner piston portion (22a, 32a) and the inner cylinder portion (21a, 31a) of the first compression mechanism portion (20) and the second compression mechanism portion (30) are arranged on the outer peripheral surface and the inner side of the inner piston portion (22a, 32a). A state where the inner peripheral surface of the cylinder part (21a, 31a) is substantially in contact at one point (first contact) (strictly, there is a micron-order gap, but refrigerant leakage in the gap does not cause a problem) ), The outer peripheral surface of the inner cylinder portion (21a, 31a) and the inner peripheral surface of the outer piston portion (22b, 32b) are substantially at one point (second contact) at a position 180 degrees out of phase with the contact. The outer piston part (22b, 32b) and the outer cylinder part (21b, 31b) have an outer peripheral surface at a position that is 180 degrees out of phase with the contact (the same position as the first contact). It is substantially in contact at one point (third contact), and the outer peripheral surface of the piston side end plate part (22c, 32c) and the outermost cylinder part (21c, 31c) It faces and is in contact with the substantially at one point (4 contact).

  In the above configuration, when the drive shaft (53) rotates, the first piston (22) swings about the center point of the swing bush portion (24c), and together with the first blade (24), the first piston (22) swings. Advances and retracts in the longitudinal direction of one blade (24). Further, when the drive shaft (53) rotates, the second piston (32) swings about the center point of the swinging bush portion (34c), and the second blade (34) together with the second blade (34). 34) Move forward and backward in the longitudinal direction.

  By the above operation, the contacts (first contact to fourth contact) of the first piston (22) and the first cylinder (21) are changed to FIGS. 6 (A) to (D) and FIGS. 7 (A) to (D), respectively. Move in order. On the other hand, each contact (1st contact-4th contact) of a 2nd piston (32) and a 2nd cylinder (31) drives with respect to a corresponding contact of a 1st piston (22) and a 1st cylinder (21). It is shifted by 180 ° around the axis of the shaft (53). That is, when viewed from above the drive shaft (53), when the operating state of the first compression mechanism (20) is as shown in FIGS. 6 (A) and 7 (A), the operating state of the second compression mechanism (30). 6C and FIG. 7C.

  In the present embodiment, the compression mechanism (40) is a four-stage compression mechanism that compresses the refrigerant into four stages in the eight cylinder chambers (23a, ..., 23d, 33a, ..., 33d).

  Specifically, the cylinder chamber of the first stage compression mechanism is formed by the outermost cylinder chambers (23d, 33d) of the first compression mechanism portion (20) and the second compression mechanism portion (30). Further, a cylinder chamber of the second stage compression mechanism is formed by the outer cylinder chamber (33c) and the inner cylinder chamber (33b) of the second compression mechanism section (30), and the outer cylinder chamber of the first compression mechanism section (20). (23c) and the inner cylinder chamber (23b) form a cylinder chamber of the third-stage compression mechanism. Furthermore, the cylinder chamber of the fourth stage compression mechanism is formed by the innermost cylinder chambers (23a, 33a) of the first compression mechanism portion (20) and the second compression mechanism portion (30). In the present embodiment, the axial length of the outer piston portions (22, 32) of the first and second compression mechanisms (20, 30) and the corresponding axial length of the cylinders (21, 31) are the same. Since they are the same, the cylinder volume of the second stage compression mechanism and the cylinder volume of the third stage compression mechanism are substantially equal.

  Thus, the compressor (1) of the present embodiment includes a cylinder (21, 31) having an annular cylinder space, and an annular piston (22, 31) arranged eccentrically with respect to the cylinder (21, 31). 32), and a plurality of cylinder chambers (23a, ..., 23d, 33a, ..., 33d) are formed between the cylinders (21, 31) and the pistons (22, 32). , 23d, 33a, ..., 33d, each having a compression mechanism (20, 30) formed with one suction port and one discharge port communicating with each of the cylinder chambers (23a, ..., 23d, 33a, ..., 33d). Four cylinder chambers (23a, ..., 23d, 33a, ..., 33d) are formed between the pair of cylinders (21,31) and pistons (22,32), and these cylinder chambers (23a, ..., 23d, 33d), the cylinder chamber (23d, 33d) of the first stage compression mechanism that compresses the low-pressure refrigerant in the first stage, and the second stage compression mechanism that compresses the discharged refrigerant of the first stage compression mechanism in the second stage. Shi The cylinder chamber (33c, 33b), the cylinder chamber (23c, 23b) of the third stage compression mechanism that compresses the refrigerant discharged from the second stage compression mechanism in the third stage, and the fourth stage compression of the refrigerant discharged from the third stage compression mechanism The cylinder chamber (23a, 33a) of the fourth stage compression mechanism is formed. The refrigerant circuit is between the first stage compression mechanism and the second stage compression mechanism, between the second stage compression mechanism and the third stage compression mechanism, and between the third stage compression mechanism and the fourth stage compression mechanism. It is good to comprise so that a refrigerant can be cooled with a cooling mechanism.

<Suction passage and discharge passage>
The compression mechanism (40) includes first to fourth suction flow paths (not shown) for guiding refrigerant from the suction pipes (60 to 63) to the cylinder chambers (23a, ..., 23d, 33a, ..., 33d). 71-74) are formed. The first to fourth suction flow paths (71 to 74) constitute the suction flow paths of the first-stage compression mechanism to the fourth-stage compression mechanism, respectively. These suction passages (71 to 74) do not cross each other, and other parts formed in the compression mechanism (40) (each blade (24, 34), discharge valve (88), etc.) Is formed in the compression mechanism (40) so as not to interfere.

  The first suction channel (71) has an inflow end connected to the suction pipe (62), and an outflow end constituted by the suction ports (P1, P1) is the outermost cylinder chamber of the first compression mechanism (20) ( 23d) and the outermost cylinder chamber (33d) of the second compression mechanism (30). The second suction flow path (72) has an inflow end connected to the suction pipe (63), and an outflow end constituted by the suction port (P2) at the inner cylinder chamber (33b) of the second compression mechanism (30). Connected to the outer cylinder chamber (33c). The third suction flow path (73) has an inflow end connected to the suction pipe (60), and an outflow end constituted by the suction port (P2) at the inner cylinder chamber (23b) of the first compression mechanism (20). Connected to the outer cylinder chamber (23c). The fourth suction flow path (74), which is the fourth stage suction portion of the compression mechanism, has an inflow end connected to the suction pipe (61), and an outflow end constituted by the suction ports (P3, P3) as the first compression mechanism. The innermost cylinder chamber (23a) of the part (20) and the innermost cylinder chamber (33a) of the second compression mechanism part (30) are connected.

  The fourth suction flow path (74) includes a suction pipe side flow path (74a) extending vertically in the compression mechanism (40) and a suction port side flow path (74b) extending horizontally in the compression mechanism (40). ) And are formed. The suction port side flow path (74b) includes a facing surface of the cylinder space side front head (15) in the stacked portion (16a) of the bearing portion side front head (16) and a stacked portion of the bearing portion side rear head (19) ( It can be easily formed by notching the facing surface of the cylinder space side rear head (18) in 19a) into a groove shape.

  The compression mechanism (40) includes first to fourth refrigerants for guiding the refrigerant compressed in the cylinder chambers (23a,..., 23d, 33a,..., 33d) to the outside of the compression mechanism (40). Discharge flow paths (81 to 84) are formed. The first to fourth discharge flow paths (81 to 84) constitute discharge flow paths of the first-stage compression mechanism to the fourth-stage compression mechanism, respectively. These discharge flow paths (81 to 84) do not cross each other and other parts formed in the compression mechanism (40) (each blade (24, 34), discharge valve (88), etc.) Is formed in the compression mechanism (40) so as not to interfere.

  The first discharge flow path (81), which is the discharge portion of the first stage compression mechanism, has an inflow end constituted by discharge ports (P11, P11) at the outermost cylinder chamber (23d) of the first compression mechanism portion (20). The second compression mechanism (30) is connected to the outermost cylinder chamber (33d), and the outflow end is connected to the discharge pipe (65). The second discharge flow path (82) has an inflow end constituted by discharge ports (P12, P13) connected to the inner cylinder chamber (33b) and the outer cylinder chamber (33c) of the second compression mechanism (30), The outflow end is connected to the discharge pipe (66). The third discharge flow path (83) has an inflow end constituted by discharge ports (P12, P13) connected to the inner cylinder chamber (23b) and the outer cylinder chamber (23c) of the first compression mechanism (20), The outflow end is connected to the discharge pipe (64). The fourth discharge flow path (84) has an inflow end constituted by discharge ports (P14, P14) at the innermost cylinder chamber (23a) of the first compression mechanism (20) and the second compression mechanism (30). It is connected to the innermost cylinder chamber (33a).

  The refrigerant from the fourth discharge channel (84) connected to the innermost cylinder chamber (23a) of the first compression mechanism (20) flows upward in the casing (10) through the muffler space (27a) and is discharged. It is discharged out of the casing (10) through the pipe (67). The refrigerant from the fourth discharge flow path (84) connected to the innermost cylinder chamber (33a) of the second compression mechanism section (30) passes through the discharge junction passage (29) formed in the compression mechanism (40). Flows into the muffler space (27a), merges with the refrigerant discharged from the first compression mechanism (20), and is discharged from the discharge pipe (67) to the outside of the casing (10).

  The compression mechanism (40) includes a plurality of discharge valves (88, 88,...). The discharge valve is constituted by a reed valve, for example. This discharge valve (88,88, ...) covers each discharge port (P11, P11, ... P14, P14), and the pressure in each cylinder chamber (23a, ..., 23d, 33a, ..., 33d) When the pressure is lower than the predetermined value, the discharge ports (P11, P11, ... P14, P14) are closed, while the pressure in each cylinder chamber (23a, ..., 23d, 33a, ..., 33d) is higher than the predetermined value. If this happens, the discharge ports (P11, P11,... P14, P14) are opened.

  As shown in FIG. 2, the middle plate (25) is formed with a fourth suction passage (74) and a first discharge passage (81), which are fluid passages through which an intermediate-pressure refrigerant flows. The fourth suction flow path (74) sucks refrigerant into the cylinder chamber of the fourth stage compression mechanism (the innermost cylinder chambers (23a, 33a) of the first compression mechanism portion (20) and the second compression mechanism portion (30)). Side fluid passage. The first discharge channel (81) discharges the refrigerant to the cylinder chamber of the first stage compression mechanism (the outermost cylinder chambers (23d, 33d) of the first compression mechanism portion (20) and the second compression mechanism portion (30)). Side fluid passage. In the fourth suction flow path (74) and the first discharge flow path (81), refrigerants having intermediate pressures different from each other flow before the fourth stage compression mechanism and after the first stage compression mechanism. ing.

  A pressing mechanism (90) is provided between the middle plate (25) and each piston-side end plate (22c, 32c) to press the piston (22, 32) against the cylinder (21, 31) with the pressure of the working fluid. It has been. The pressing mechanism (90) includes a first seal ring (91) disposed around the rotation center of the piston (22, 32) and a diameter larger than that of the first seal ring (91). A second seal ring (92) disposed on the outer peripheral side of the ring (91), and an annular portion formed between the first seal ring (91) and the second seal ring (92) for introducing a working fluid ( Annular groove) (93a, 93b). This annular part (93a, 93b) is a first annular part (between the first seal ring (91) and the second seal ring (92) on the upper surface of the body part (25a) of the middle plate (25). 93a) and a second annular portion (93b) formed between the first seal ring (91) and the second seal ring (92) on the lower surface of the lid portion (25b) of the middle plate (25). Yes.

  In the compression mechanism (40), as described above, the fourth suction passage (74) and the first discharge passage (81) are formed in the middle plate (25) as a fluid passage through which the intermediate-pressure refrigerant flows. Has been. The middle plate (25) is formed with intermediate pressure introduction passages (96a, 96b) for introducing a part of the refrigerant flowing through the fluid passages (74, 81) into the annular portions (93a, 93b). Yes. The intermediate pressure introduction path (96a, 96b) is connected to the fourth suction flow path (74) and the first annular part (93a) which are the suction parts of the fourth stage compression mechanism in the first compression mechanism part (20). The first intermediate pressure introduction path (96a) that communicates with the first discharge flow path (81) and the second annular portion (93b) that are discharge portions of the first stage compression mechanism in the second compression mechanism portion (30). And a second intermediate pressure introduction passage (96b) communicating therewith.

  A detailed configuration of the fluid passage (74, 81) will be described with reference to FIG. 8 which is a cross-sectional view of the main body (25a) of the middle plate (25). As shown in FIGS. 2 and 8, the first discharge channel (81) is a rectangular parallelepiped discharge space (between the body (25a) and the lid (25b)) of the middle plate (25). 81a), and the discharge space (81a) of the first stage compression mechanism and the discharge pipe (65) communicate with each other. The discharge space (81a) communicates with the cylinder chamber (23d, 33d) of the first stage compression mechanism via the discharge port (P11, P11). Further, the lid portion (25b) of the middle plate (25) has a first stage discharge space (81a) and a second annular portion (93b) constituting a part of the first discharge flow path (discharge portion) (81). The second intermediate pressure introduction passage (96b) communicating with the second intermediate pressure passage is formed.

  The suction pipe side flow path (74a) of the fourth suction flow path (74) is formed at a position displaced by a predetermined angle in the circumferential direction with respect to the position of the suction pipe (61) of the fourth stage compression mechanism. The suction pipe (61) and the suction pipe side flow path (74a) are connected by a curved communication path (74c). The first intermediate pressure introduction passage (96a) communicates with the middle plate (25) through the communication passage (74c) and communicates with the suction portion (74) of the fourth-stage compression mechanism and the first annular groove (93a). Is formed. The suction pipe (61) of the fourth stage compression mechanism and the suction pipe (62) of the first stage compression mechanism are actually formed at the same height in FIGS. In order to clearly show the connection relationship between the fluid passages (74, 81), the positions of the suction pipe (61) and the suction pipe (62) are shifted up and down, and the shape of the passage is simplified.

  As shown in FIG. 2, the third discharge flow path (83) includes a discharge space (83a) of a third-stage compression mechanism formed in the bearing portion side front head (16), and the discharge space (83a) and The third discharge channel (83) and the discharge pipe (64) communicate with each other. The fourth discharge flow path (84) is a discharge space (84a) of the fourth stage compression mechanism formed in the bearing portion side front head (16). In this embodiment, the discharge space (83a) of the third-stage compression mechanism, which is a lower-stage compression mechanism than the fourth-stage compression mechanism, communicates with the muffler space (27a) via the relief mechanism (41). In addition, the discharge space (84a) of the fourth stage compression mechanism, which is the highest stage compression mechanism, also communicates with the muffler space (27a). Therefore, in this embodiment, the discharge space (83a) of the third-stage compression mechanism and the discharge space (84a) of the fourth-stage compression mechanism communicate with each other.

  The middle plate (25), the first compression mechanism (20) disposed above the middle plate (25), and the second compression mechanism (30) disposed below. In the compression mechanism (40), the relief mechanism (41) is provided in the first compression mechanism section (20) located on the upper side.

  The relief mechanism (41) includes a relief port (42) communicating with the discharge space (83a) and the muffler space (27a) of the third-stage compression mechanism, and a relief valve (43) attached to the relief port (42). ). As the relief valve (43), for example, a reed valve can be used. The relief valve (43) is opened under operating conditions in which the high pressure of the refrigerant circuit decreases and the discharge pressure of the third stage compression mechanism becomes higher than the high pressure.

  Therefore, in this embodiment, when the operating condition is such that the discharge pressure of the third stage compression mechanism exceeds the high pressure of the system (refrigerant circuit), the discharge valve (88) is always open in the fourth stage compression mechanism. Therefore, in the fourth stage compression mechanism, the refrigerant only passes and is not compressed. And since the discharge pressure of a 3rd stage compression mechanism equalizes to the high pressure of a refrigerant circuit and does not raise any more, it can prevent that the discharge pressure of a compressor (1) increases too much.

<Oil supply structure to blade and pressure setting structure of blade back pressure space>
As shown in FIG. 9, an oil supply pump (54) is provided at the lower end of the drive shaft (53). Inside the drive shaft (53), an oil supply passage (55) communicating with the oil supply pump (54) is formed along the axis of the drive shaft (53). The oil supply passage (55) communicates with the oil supply pump (54) at the lower end portion of the drive shaft (53), while the upper end position is slightly above the upper end of the first eccentric portion (53a). The drive shaft (53) includes a first oil supply hole (55a) that opens to the outer peripheral surface at an intermediate portion in the vertical direction of the first eccentric portion (53a) and an intermediate portion in the vertical direction of the second eccentric portion (53b). A second oil supply hole (55b) that opens to the outer peripheral surface at the portion is formed. Further, the drive shaft (53) includes a third oil supply hole (55c) opened to the outer peripheral surface of the drive shaft (53) immediately above the first eccentric portion (53a), and a second eccentric portion (53b). A fourth oil supply hole (55d) is formed immediately below and on the outer peripheral surface of the drive shaft. The first oil supply hole (55a), the second oil supply hole (55b), the third oil supply hole (55c), and the fourth oil supply hole (55d) each communicate with the oil supply passage (55).

  As shown in FIGS. 3, 5 and 9, the cylinder body (21c) of the first cylinder (21) has a groove (sliding groove) (21f) on the outer side in the radial direction of the first cylinder (21). The above-described first blade back pressure space (21g) that communicates is provided. Further, the second main body (31c) of the second cylinder (31) has a second blade back pressure space (communication on the radially outer side of the second cylinder (31) with respect to the groove (slide groove) (31f) ( 31g) is provided. As shown in FIG. 9, the first blade back pressure space (21g) and the second blade back pressure space (31g) communicate with each other via a back pressure communication path (58a) formed in the middle plate (25). ing.

  As shown in FIG. 9, the oil introduction for introducing the high pressure oil in the oil reservoir (10a) into the first blade back pressure space (21g) and the second blade back pressure space (31g) is introduced into the rear head (17). A path (57) is provided. The oil introduction path (57) includes an oil introduction pipe (57a) and an oil introduction hole (57b). The oil introduction pipe (57a) is fixed to the lower surface of the bearing portion side rear head (19), and its lower end is positioned in the oil in the oil reservoir (10a). The oil introduction hole (57b) is formed in the cylinder space side rear head (18) and the bearing portion side rear head (19), and communicates with the second blade back pressure space (31g) and the oil introduction pipe (57a). In this configuration, when high-pressure oil in the oil reservoir (10a) is introduced into the first blade back pressure space (21g) and the second blade back pressure space (31g), the blades (24, 34) are moved downward in FIG. Pressed to.

-Driving action-
Next, the operation of the compressor (1) will be described. Here, the operations of the first and second compression mechanisms (20, 30) are performed in a state where the phases are different from each other by 180 °.

  When the electric motor (50) is started, in the first compression mechanism (20), the rotation of the rotor (52) is transmitted to the first piston (22) via the first eccentric part (53a) of the drive shaft (53). The first piston (22) swings about the center point of the swing bush portion (24c) and moves forward and backward in the longitudinal direction of the first blade (24) together with the first blade (24). . As a result, the first piston (22) revolves while swinging with respect to the first cylinder (21), and is predetermined in the four cylinder chambers (23a, 23b, 23c, 23d) of the first compression mechanism (20). The compression operation is performed.

  At this time, the blade inner end (24d), which is the tip of the inner blade portion (B1), comes into contact with the surface of the notch portion (n1) of the inner piston portion (22a). The blade outer end (24e), which is the tip of the outer second blade portion (B3), comes into contact with the surface of the notch (n2) of the piston side end plate portion (22c). Therefore, the blade (24) slides while contacting the piston (22) during the operation of the compression mechanism (40), so that the refrigerant leaks from the high pressure side to the low pressure side of the cylinder chamber (C1, C2). It can be suppressed.

  In the innermost cylinder chamber (23a) and the outer cylinder chamber (23c), the drive shaft (53) rotates clockwise from the state shown in FIG. 6 (A) and is changed as shown in FIG. 6 (B) to FIG. 6 (D). As the state changes, the volume of the low pressure chamber (23aL, 23cL) increases, and the refrigerant is sucked into the low pressure chamber (23aL, 23cL) from the suction port (P3, P2). Further, when the drive shaft (53) makes one revolution and again enters the state of FIG. 6 (A), the suction of the refrigerant into the low pressure chambers (23aL, 23cL) is completed. The low-pressure chamber (23aL, 23cL) becomes a high-pressure chamber (23aH, 23cH) in which the refrigerant is compressed, and a new low-pressure chamber (23aL, 23cL) is formed across the first blade (24). When the drive shaft (53) further rotates, the suction of the refrigerant is repeated in the low-pressure chamber (23aL, 23cL), while the volume of the high-pressure chamber (23aH, 23cH) decreases, and the refrigerant flows in the high-pressure chamber (23aH, 23cH). Compressed. When the pressure in the high pressure chamber (23aH, 23cH) reaches a preset value and the differential pressure from the discharge flow path (84, 83) reaches a set value, the discharge valve ( 88, 88) is opened, and the refrigerant is discharged from the fourth discharge passage (84) and the third discharge passage (83) to the outside of the first compression mechanism section (20).

  In the outermost cylinder chamber (23d), the drive shaft (53) rotates clockwise from the state shown in FIG. 7 (A) and changes from the state shown in FIG. 7 (B) to FIG. 7 (D). Accordingly, the volume of the low pressure chamber (23dL) increases, and the refrigerant is sucked into the low pressure chamber (23dL) from the suction port (P1). Further, when the drive shaft (53) makes one revolution and again enters the state of FIG. 7 (A), the suction of the refrigerant into the low pressure chamber (23dL) is completed. The low pressure chamber (23dL) becomes a high pressure chamber (23dH) in which the refrigerant is compressed, and a new low pressure chamber (23dL) is formed across the first blade (24). When the drive shaft (53) further rotates, the suction of the refrigerant is repeated in the low pressure chamber (23dL), while the volume of the high pressure chamber (23dH) is reduced, and the refrigerant is compressed in the high pressure chamber (23dH). When the pressure in the high pressure chamber (23dH) reaches a predetermined value and the differential pressure from the discharge flow path (81) reaches a set value, the discharge valve (88) is opened by the pressure of the refrigerant in the high pressure chamber (23dH), and the refrigerant Is discharged from the first discharge channel (81) to the outside of the first compression mechanism (20).

  On the other hand, in the inner cylinder chamber (23b), the drive shaft (53) rotates clockwise from the state of FIG. 6 (C) and changes to the state of FIGS. 6 (D) to 6 (B). Accordingly, the volume of the low pressure chamber (23bL) increases, and the refrigerant is sucked into the low pressure chamber (23bL) from the suction port (P2). Further, when the drive shaft (53) makes one revolution and again enters the state of FIG. 6 (C), the suction of the refrigerant into the low pressure chamber (23bL) is completed. The low pressure chamber (23bL) becomes a high pressure chamber (23bH) in which the refrigerant is compressed, and a new low pressure chamber (23bL) is formed across the first blade (24). When the drive shaft (53) further rotates, the suction of the refrigerant is repeated in the low pressure chamber (23bL), while the volume of the high pressure chamber (23bH) is reduced, and the refrigerant is compressed in the high pressure chamber (23bH). When the pressure in the high pressure chamber (23bH) reaches a predetermined value and the differential pressure with respect to the discharge flow path (83) reaches a set value, the discharge valve (88) is opened by the pressure of the refrigerant in the high pressure chamber (23bH), and the refrigerant Is discharged from the discharge flow path (83) to the outside of the first compression mechanism (20).

  The outer cylinder chamber (23c) and the inner cylinder chamber (23b) are approximately 180 degrees different in refrigerant suction start timing and discharge start timing. As a result, the discharge pulsation is reduced, and vibration and noise are reduced.

  On the other hand, in the second compression mechanism (30), the rotation of the rotor (52) is transmitted to the second piston (32) via the second eccentric part (53b) of the drive shaft (53), and the second piston ( 32) swings with the center point of the swing bush portion (34c) as the swing center, and moves forward and backward in the longitudinal direction of the second blade (34) together with the second blade (34). As a result, the second piston (32) revolves while swinging with respect to the second cylinder (31), and is predetermined in the four cylinder chambers (33a, 33b, 33c, 33d) of the second compression mechanism (30). The compression operation is performed.

  The compression operation in the second compression mechanism section (30) is substantially the same as the compression operation in the first compression mechanism section (20), and the refrigerant is compressed in each cylinder chamber (33a, 33b, 33c, 33d). The In each cylinder chamber (33a, 33b, 33c, 33d), the pressure in the high pressure chamber (33aH, 33bH, 33cH, 33dH) becomes a predetermined value and the differential pressure from each discharge flow path (84, 83, 83, 81) Reaches the set value, the discharge valve (88, 88, 88, 88) is opened by the pressure of the refrigerant in the high-pressure chamber (33aH, 33bH, 33cH, 33dH), and the refrigerant flows into each discharge channel (84, 82, 82). , 81) is discharged to the outside of the second compression mechanism section (30).

  During the operation of the compression mechanism (40), the refrigerant flows from the suction pipe (62) to the outermost cylinder chamber (23d) of the first compression mechanism section (20), which is the cylinder chamber of the first stage compression mechanism, and the second compression mechanism. The air is sucked into the outermost cylinder chamber (33d) of the section (30), compressed, and discharged from the cylinder chamber of the first stage compression mechanism through the discharge pipe (65). For example, during cooling operation, as shown in FIG. 10, the refrigerant discharged from the cylinder chamber of the first stage compression mechanism is cooled and then is supplied from the suction pipe (63) to the cylinder chamber of the second stage compression mechanism. 2 It is sucked into the outer cylinder chamber (33c) and the inner cylinder chamber (33b) of the compression mechanism section (30), further compressed, and discharged from the cylinder chamber of the second stage compression mechanism through the discharge pipe (66). After the refrigerant discharged from the cylinder chamber of the second stage compression mechanism is cooled, the outer cylinder chamber (23c) of the first compression mechanism section (20) which is the cylinder chamber of the third stage compression mechanism from the suction pipe (60). ) And the inner cylinder chamber (23b), further compressed, and discharged from the cylinder chamber of the third stage compression mechanism through the discharge pipe (64). After the refrigerant discharged from the cylinder chamber of the third-stage compression mechanism is cooled, the innermost cylinder chamber of the first compression mechanism section (20), which is the cylinder chamber of the fourth-stage compression mechanism, from the suction pipe (61) ( 23a) and the innermost cylinder chamber (33a) of the second compression mechanism section (30) and further compressed, and discharged from the cylinder chamber of the fourth stage compression mechanism through the discharge pipe (67).

  The refrigerant discharged from the cylinder chamber of the fourth-stage compression mechanism sequentially flows through a radiator, an expansion mechanism, and an evaporator of a refrigerant circuit (not shown), and is sucked into the compressor (1) again. A refrigeration cycle is performed by sequentially repeating a compression stroke in the compressor (1), a heat release stroke in the radiator, an expansion stroke in the expansion mechanism, and an evaporation stroke in the evaporator.

  During the operation of the compression mechanism (40), the lubricating oil accumulated in the oil sump (10a) at the bottom of the casing (10) is sucked up by the oil feed pump (54) and is supplied to the oil supply passage (55) of the drive shaft (53). ). The lubricating oil flowing through the oil supply passage (55) is divided into the first to fourth oil supply holes (55a to 55d). Lubricating oil is supplied from the first oil supply hole (55a) to the sliding surface between the first eccentric part (53a) and the inner piston part (22a) of the first piston (22). (55b) is supplied to the sliding surface between the second eccentric part (53b) and the inner piston part (32a) of the second piston (32).

  Further, in FIG. 9, the lubricating oil in the oil reservoir is introduced into the first blade back pressure space (21g) and the second blade back pressure space (31g) through the oil introduction path (57). As a result, the insides of the first blade back pressure space (21g) and the second blade back pressure space (31g) become high pressure, and the blades (24, 34) are pressed downward in FIG. Therefore, the blade (24, 34) has a swing bush (24c, 34c), an inner end (blade inner end) (24d, 34d) and an outer end (blade outer end) (24e, 34d) each having a piston ( 22 and 32) abut on the notches (n1, n2). As a result, the blade (24, 34) receives a force with a large pressure receiving area, and the pressing load is dispersed, so that the tip of the blade (24, 34) and the swinging bush (24c, 34c) wear. It can be suppressed.

-Effect of the embodiment-
According to the present embodiment, in the compression mechanism (20, 30) having four cylinder chambers, the blades (24, 34) and the pistons (22, 32) are connected to the rocking bush portions (24c, 34c) and the blade outer side. Abutment is made at three locations, the end (24e, 34e) and the blade inner end (24d, 34d), so that the pressing load at the contact portion between the blade (24, 34) and the piston (22, 32) is dispersed. Therefore, the seizure in the swinging bush portions (24c, 34c) can be suppressed. Therefore, the reliability of the compressor (1) is prevented from being lowered, and the compressor is caused by the refrigerant leaking from the high pressure side to the low pressure side of the cylinder chamber (23a, ..., 23d, 33a, ..., 33d). The performance degradation of (1) can be suppressed.

-Modification of the embodiment-
The modification of the embodiment shown in FIGS. 11 and 12 is an example in which the shapes of the blade inner end (24d) and the blade outer end (24e) are different from those of the above embodiment.

  Specifically, as shown in FIGS. 11A and 12, the blade inner end (inner end portion of the inner blade portion (B1)) (24d) and the inner peripheral piston portion (inner piston portion) (22a ) Are in contact with each other at the notch (n1), and the inner end (24d) of the blade and the notch (n1) of the piston (22a) on the inner peripheral side of the inner end (24d) of the blade They are formed with the same radius of curvature determined based on the trajectory of the swinging motion.

  Further, as shown in FIGS. 11B and 12, the blade outer end (the inner end of the short portion (24b)) (24e) and the outer peripheral piston portion (piston side end plate portion) (22c) are notched. The blade outer end (24e) and the notch (n2) of the outer peripheral piston part (22c) are formed on the locus of the swinging motion of the blade outer end (24e). It is formed with the same curvature radius determined based on the above.

  According to this modification, the blade outer end (inner end of the short portion (24b)) (24e) and the notch (n2) of the outer piston portion (piston side end plate portion) (22c) are connected to the blade outer end ( Since they are made to contact each other by being formed with a radius of curvature determined based on the trajectory of the swinging operation of 24e), the pressing load on the outer piston portion (22c) can be more reliably dispersed. . Further, the blade inner end (inner end portion of the inner blade portion (B1)) (24d) and the notch (n1) of the inner peripheral side piston portion (inner piston portion) (22a) are connected to the blade inner end (24d). By forming with a radius of curvature determined based on the trajectory of the oscillating motion, they are in contact with each other, so that the pressing load on the inner circumferential side piston portion (22a) can be more reliably dispersed. And the pressing load of the swinging bush part (24c, 34c) is also dispersed, so that seizure in the swinging bush part (24c, 34c) is suppressed and the reliability of the compressor (1) is reliably prevented from being lowered. In addition, the deterioration of the performance of the compressor (1) due to refrigerant leakage from the high pressure side to the low pressure side of the cylinder chamber (23a,..., 23d, 33a,.

<< Other Embodiments >>
About the said embodiment, it is good also as the following structures.

  For example, although the four-stage compression mechanism has been described in the above embodiment, in the present invention, a plurality of cylinder chambers are formed between the pistons (22, 32) and the cylinders (21, 31). , 34) can be applied to the rotary compressor (1) provided with the eccentric rotation type compression mechanism (40) divided into the high pressure side and the low pressure side, and the application target is limited to the four-stage compression mechanism. Is not to be done.

  The piston (22, 32) and the blade (24, 34) include an opposing portion between the inner peripheral piston portion (22a, 32a) and the blade inner end (24d, 34d), and an outer peripheral piston portion (22c, 32c) and the blade outer end (24e, 34e) may be formed so as to be in contact with each other, and it is not necessary to make contact with both of these facing portions.

Further, in the above embodiment, the swing bush portion (24c, 34c) is integrated with the blade (24, 34) . However, as a reference technique of the blade (24, 34) of this embodiment, FIG. 13, the configuration in which the swinging bush portion (24c, 34c) is separated from the inner blade portion (B1) of the blade (24, 34), or the deformation of FIG. 12 as shown in FIG. The blades (24, 34) according to the example may be configured such that the swinging bush portions (24c, 34c) are separated from the inner blade portion (B1).

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention includes a cylinder, a piston that rotates eccentrically in the cylinder, and an annular cylinder chamber that is divided into a plurality of sections from the inner periphery side to the outer periphery side between the piston and the cylinder. The present invention is useful for a rotary compressor including a compression mechanism having a high-pressure side and a blade that partitions the low-pressure side.

1 Rotary compressor
21 1st cylinder
21g Blade back pressure space
22 First piston
22a Inner piston part (inner circumference side piston part)
22b Outer piston part (ring piston part)
22c End plate of piston side (outer piston side)
23a Innermost cylinder chamber
23b Inner cylinder chamber
23c Outer cylinder chamber
23d Outermost cylinder chamber
24 First blade
24c Swing bush
24d blade inner edge
24e Blade outer edge
31 2nd cylinder
31g Blade back pressure space
32 2nd piston
32a Inner piston part (inner circumference side piston part)
32b Outer piston part (ring-shaped piston part)
32c Piston end plate (outside piston)
33a Innermost cylinder chamber
33b Inner cylinder chamber
33c Outer cylinder chamber
33d Outermost cylinder chamber
34 Second blade
34c Swing bush
34d Blade inner edge
34e Blade outer edge
40 Compression mechanism

Claims (4)

Formed between the cylinder (21, 31), the piston (22, 32) that rotates eccentrically in the cylinder (21, 31), and the cylinder (21, 31) and the piston (22, 32). A compression mechanism (40) having a cylinder chamber (23a, ..., 23d, 33a, ..., 33d) having blades (24, 34) dividing the high pressure chamber and the low pressure chamber;
The compression mechanism (40) has a blade back pressure space (21g, 31g) for applying pressure radially inward to the blade (24, 34),
Ring piston portions (22b, 32b) so that the piston (22, 32) partitions the cylinder chamber (23a, ..., 23d, 33a, ..., 33d) into a plurality of cylinder chambers from the inner peripheral side to the outer peripheral side. ), An inner peripheral piston portion (22a, 32a) positioned on the inner peripheral side of the ring-shaped piston portion (22b, 32b), and an outer peripheral piston portion positioned on the outer peripheral side of the ring-shaped piston portion (22b, 32b) (22c, 32c)
The blades (24, 34) are radially connected to the swinging bush portions (24c, 34c) connected to the ring-shaped piston portions (22b, 32b) so as to be swingable and the inner circumferential side piston portions (22a, 32a). A rotary compressor which is an integral member having a blade inner end (24d, 34d) opposed from the outside and a blade outer end (24e, 34e) opposed from the radially outer side to the outer piston portion (22c, 32c). There,
The piston (22, 32) and the blade (24, 34) include an opposing portion between the inner peripheral piston portion (22a, 32a) and the blade inner end (24d, 34d), and an outer peripheral piston portion (22c, 32c). Rotating compressor characterized in that it is formed so as to abut on at least one of the opposing portions of the blade and the outer end of the blade (24e, 34e) and the connecting portion of the swing bush portion (24c, 34c) . In claim 1,
The blade outer end (24e, 34e) and the outer side piston part (22c, 32c) are formed to contact each other, and the blade outer end (24e, 34e) and the outer side piston part (22c, 32c) A rotary compressor characterized in that the blade outer end (24e, 34e) is formed by an arcuate curved surface having the same trajectory and diameter as the swinging motion. In claim 1 or 2,
The blade inner end (24d, 34d) and the inner peripheral piston portion (22a, 32a) are formed to contact each other. The blade inner end (24d, 34d) and the inner peripheral piston portion (22a, 32a) A rotary compressor characterized in that it is formed by a curved surface having the same arc shape as the trajectory of the swinging motion of the blade inner ends (24d, 34d). In any one of Claims 1-3,
The compression mechanism (40) includes, in order from the radially inner side to the radially outer side, the innermost cylinder chamber (23a, 33a), the inner cylinder chamber (23b, 33b), the outer cylinder chamber (23c, 33c) and the outermost cylinder. It has four cylinder chambers (23a, ..., 23d, 33a, ..., 33d) of cylinder chambers (23d, 33d),
The blade inner end (24d, 34d) is disposed in the innermost cylinder chamber (23a, 33a), and the blade outer end (24e, 34e) is disposed in the outermost cylinder chamber (23d, 33d). And rotary compressor.

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