JP4828915B2 - Scroll type fluid machine - Google Patents

Description

  The present invention relates to a scroll fluid machine suitable for use in a compressor such as air or refrigerant, a vacuum pump, or the like.

  In general, a scroll fluid machine performs compression or pumping operation of air, refrigerant, and the like by rotating a revolving scroll with respect to a fixed scroll, and is used as, for example, an air compressor (for example, Patent Documents). 1).

JP 2005-139976 A

  In this type of conventional scroll-type air compressor, a fixed scroll provided in a casing and a orbiting scroll that is disposed so as to be orbitable in the casing face each other. Each of the fixed scroll and the orbiting scroll has a spiral wrap portion standing on the surface of the end plate formed in a disc shape, and a plurality of compression chambers are defined between the wrap portions of each scroll. Has been. Further, a connecting portion that is connected to the drive side protrudes from the rear surface of the end plate of the orbiting scroll.

  The casing is provided with a drive shaft that is rotatably supported by the main bearing. One end of the drive shaft is connected to the connecting portion of the orbiting scroll via the orbiting bearing, and the other end is connected to the output shaft of the motor.

  During the operation of the compressor, when the drive shaft is rotationally driven by the motor, this rotation is converted into a turning motion of the orbiting scroll, thereby performing a compression operation. In this case, an anti-rotation mechanism such as an auxiliary crank that prevents the rotation of the orbiting scroll is provided between the orbiting scroll and the casing.

  A cooling fan that rotates together with the drive shaft between the casing and the motor is provided on the outer peripheral side of the drive shaft. The cooling fan generates cooling air inside a fan cover provided between the casing and the motor, and cools the fixed scroll and the orbiting scroll with the cooling air.

  Further, in the prior art, in order to improve heat resistance of, for example, a main bearing and a swivel bearing, the connecting portion of the orbiting scroll is formed as a bottomed tubular body, and the drive shaft is also formed in a tubular shape. As a result, in the prior art, when the heat generated on the compression chamber side is transmitted to each bearing through the connection portion and the drive shaft, the cross-sectional area of the heat conduction path is reduced, and the surface area (heat radiation area) of the connection portion and the drive shaft is reduced. ) Is increased.

  On the other hand, as another conventional technique, a scroll-type compression is configured in which a drive shaft is formed in a cylindrical shape, a cooling passage is provided on the inner peripheral side, and a cooling medium is circulated through the cooling passage to cool the slewing bearing and the like. A machine is also known (see, for example, Patent Document 2).

Japanese Utility Model Publication No. 64-32487

  In this case, the cooling passage is connected to a cooling medium supply device or the like disposed outside the compressor, and receives supply of the cooling medium from this device. A cooling fan that cools the orbiting scroll and the like by rotating together with the drive shaft is provided in the casing of the compressor.

  By the way, in the prior art described in Patent Document 1, the connecting portion of the orbiting scroll and the drive shaft are formed as a hollow cylindrical body, or the cooling fan is rotated between the casing and the motor, so that the whole It is configured to increase heat resistance.

  However, in order to obtain high heat resistance, for example, when a large space is provided on the inner peripheral side of the connecting portion or the drive shaft, these members become thin and the strength is reduced. For this reason, there is a limit to thinning the connecting portion and the drive shaft, and high heat resistance can be obtained simply by forming the connecting portion and the drive shaft into a cylindrical shape as in the prior art of Patent Document 1. There is a problem that it is difficult.

  Further, when the compressor is operated, the cooling fan rotates in the vicinity of the casing, so that the casing is strongly cooled as compared with other parts. Therefore, a large temperature difference is easily generated between the casing and the orbiting scroll. . For this reason, in the prior art of Patent Document 1, an unexpected external force is applied to a component such as an auxiliary crank due to a difference in thermal deformation between the casing and the orbiting scroll, which may cause early wear or distortion of the component. There is a problem that durability is lowered.

  On the other hand, in the prior art described in Patent Document 2, the cooling medium is circulated through the cooling passage in the drive shaft. However, in this case, for example, the outer diameter portion of each scroll, the auxiliary crank, and other structures are separated from the drive shaft and may not be sufficiently cooled. For this reason, in the prior art of Patent Document 2, a structure such as a cooling fan for cooling the inside of the casing is required in addition to the structure for circulating the cooling medium in the drive shaft, and the entire cooling structure is complicated. is there.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to enable efficient cooling of bearings such as main bearings and slewing bearings with a simple cooling structure. It is to provide a scroll type fluid machine that can protect the heat and improve the heat resistance.

  Another object of the present invention is to suppress variation in cooling efficiency between the casing and the orbiting scroll, and to protect the parts arranged between these from early wear and distortion, and to improve durability. It is an object of the present invention to provide a scroll fluid machine that can be improved.

  Still another object of the present invention is to provide a scroll type fluid machine that can suppress heat from being transmitted from a casing or a driving source to a duct, maintain cooling air flowing in the duct at a low temperature, and improve cooling efficiency. Is to provide.

  In order to solve the above-described problems, the present invention provides a casing, a fixed scroll provided on the casing and provided with a spiral wrap portion on the surface of the end plate, and a surface of the end plate provided in a rotatable manner in the casing. A spiral scroll that overlaps the wrap portion of the fixed scroll and a connecting scroll provided on the back surface of the end plate, and a rotary scroll provided in the casing via a main bearing. The present invention is applied to a scroll type fluid machine including a drive shaft connected to a connecting portion of the orbiting scroll through an orbiting bearing, and a drive source for rotating the orbiting scroll by rotating the drive shaft.

A feature of the configuration adopted by the invention of claim 1 is that the drive shaft is provided with a cooling air passage extending in the axial direction through the inner peripheral side of the main bearing and through which cooling air flows, and the cooling air passage An inflow side opening communicating with the main bearing is provided so as to open to an outer peripheral side of the connecting portion on the back side of the orbiting scroll, and an outflow side opening communicating with the cooling air passage is sandwiched between the main bearing and the inflow side. The cooling air that is provided so as to open on the opposite side of the opening and the axial direction and flows through the orbiting scroll side air passage provided on the back side of the orbiting scroll flows in from the inflow side opening and from the outflow side opening. It is in the structure which flows out.

According to a second aspect of the present invention, the connecting portion of the orbiting scroll is a boss protruding toward the back side of the end plate, and the connecting portion communicates with the cooling air passage and passes through the inner peripheral side of the orbiting bearing. is a set Keru constituting the auxiliary cooling air passage extending in the axial direction Te.

According to a third aspect of the present invention, the drive shaft is provided with a cooling fan that generates cooling air at a position corresponding to the outflow side opening.

According to a fourth aspect of the present invention, the drive shaft is provided with a cooling air passage extending in an axial direction through the inner peripheral side of the main bearing and through which cooling air flows, and an inflow side opening communicating with the cooling air passage. Is provided so as to open to the back side of the orbiting scroll from the main bearing, and an outflow side opening communicating with the cooling air passage is opened to the opposite side of the inflow side opening with respect to the inflow side opening across the main bearing. The cooling air flows from the inflow side opening and flows out from the outflow side opening, and the drive shaft is provided with a cooling fan that generates cooling air at a position corresponding to the outflow side opening, A heat insulating cover formed of a heat insulating material is provided between the back side of the casing and the cooling fan.

  On the other hand, according to the invention of claim 5, the drive shaft is provided with a cooling fan that rotates together with the drive shaft between the back side of the casing and the drive source, and surrounds the cooling fan and the casing. A duct for guiding cooling air to the fixed scroll and the orbiting scroll is provided, and a heat insulating cover formed of a material having a heat insulating property is provided between the rear side of the casing and the cooling fan. It is configured.

According to a sixth aspect of the present invention, the drive shaft is provided with a cooling air passage extending in the axial direction through the inner peripheral side of the main bearing and through which cooling air flows, and the cooling scroll is connected to the connecting portion of the orbiting scroll. An inflow side opening that communicates with the air passage is provided, and the drive shaft is provided with an outflow side opening that opens on the opposite side of the inflow side opening in the axial direction across the main bearing.

According to the first aspect of the present invention, the drive shaft can be provided with a cooling air passage, and the inflow side opening and the outflow side opening communicating with the cooling air passage are open on both sides in the axial direction across the main bearing. Can be made. When the scroll fluid machine is in operation, for example, cooling air can be flowed into the cooling air passage from the inflow side opening, and this cooling air can be discharged from the outflow side opening. Further, cooling air can be circulated in the cooling air passage from the outflow side opening toward the inflow side opening. In this way, cooling air can be circulated in the connecting portion of the orbiting scroll and inside the drive shaft at a position on the inner peripheral side of the main bearing, so these parts and the main bearing are efficiently cooled by the cooling air. can do.

  Therefore, for example, even if only a cooling air passage having a minimum flow passage area is provided, it is possible to reliably prevent the compression heat generated on the orbiting scroll side from being transmitted to the main bearing, and keep the main bearing at a low temperature. be able to. As a result, the main bearing can be reliably protected from thermal deterioration without providing a large-diameter space in the drive shaft, and the heat resistance is increased while ensuring sufficient drive shaft strength. Can do.

In addition, since the inflow side opening is arranged on the outer peripheral side of the connecting part on the back side of the orbiting scroll with respect to the main bearing, the cooling air flowing through the orbiting scroll side air passage provided on the back side of the orbiting scroll is allowed to enter the inflow side opening. as possible de be made to flow in. As a result, for example, cooling air generated by one cooling fan or the like can be circulated between the inside of the drive shaft and the space in the casing. Can also be cooled together. Accordingly, there is no need to provide a dedicated cooling means for cooling the drive shaft from the inside and another cooling means for cooling the inside of the casing, so that the entire cooling structure can be simplified.

Further, according to the invention of claim 2, the inflow side opening can be opened to the outer peripheral side of the connecting portion, and between the inflow side opening and the cooling air passage, the inner peripheral side of the swivel bearing is passed. An auxiliary cooling air passage extending in the axial direction can be provided. And since cooling air can be distribute | circulated over these cooling air passages and auxiliary | assistant cooling air passages, not only a main bearing but a turning bearing can be cooled efficiently from an inner peripheral side, and the whole heat resistance is improved. Can be improved .

According to the invention of claim 3, the cooling fan can also be rotated by the drive source, and the cooling fan can generate the cooling air at a position corresponding to the outflow side opening. Thereby, the cooling fan can suck out the cooling air from the outflow side opening or send the cooling air into the outflow side opening, whereby the cooling air can be efficiently distributed to the cooling air passage.

  According to the invention of claim 4, the heat insulating cover can shield the rear side of the casing from the cooling fan, and can substantially equalize the amount of thermal deformation between the casing and the orbiting scroll. Thereby, it can prevent that components, such as a rotation prevention mechanism arrange | positioned between a casing and a turning scroll, receive unexpected external force by the difference of both thermal deformation amount, and can improve durability.

  On the other hand, according to the invention of claim 5, the cooling fan can be rotated between the back side of the casing and the drive source, thereby generating cooling air in the duct. Then, the fixed scroll and the orbiting scroll can be cooled by guiding the cooling air through the duct.

  At this time, the heat insulating cover can be interposed between the back side of the casing and the duct attached to the back side. Thereby, the heat insulation cover can suppress reliably that the compression heat etc. which generate | occur | produce on the turning scroll side are transmitted to a duct from a casing, or this heat is transmitted to the cooling wind which flows through the inside of a duct. Therefore, the fixed scroll and the orbiting scroll can be cooled by the low-temperature cooling air, and the cooling efficiency can be increased.

  Further, the heat insulating cover can shield the back side of the casing from the cooling fan. As a result, since the cooling air does not directly contact the back side of the casing, the casing can be prevented from being cooled more strongly than the orbiting scroll, and the cooling state of both can be brought closer. As a result, the amount of thermal deformation between the casing and the orbiting scroll can be made substantially uniform, and parts such as the rotation prevention mechanism arranged between them can be prevented from receiving an unexpected external force due to the difference in the amount of thermal deformation. . Therefore, early wear and distortion of such parts can be prevented, and durability can be improved.

Further, according to the invention of claim 6 , the cooling air can be circulated in the cooling air passage from, for example, the inflow side opening to the outflow side opening. A bearing etc. can be cooled efficiently. In this case, for example, the cooling air generated by one cooling fan or the like can be circulated through the inside of the drive shaft and the space in the casing, so that the overall cooling efficiency can be enhanced by a simple cooling structure.

  Hereinafter, as a scroll type fluid machine according to an embodiment of the present invention, a scroll type air compressor will be described as an example and described in detail with reference to the accompanying drawings.

  Reference numeral 1 denotes a casing that constitutes the outer shell of the compressor. The casing 1 is made of a metal material such as aluminum, for example, and is formed in a bottomed cylindrical shape that is open on one side in the axial direction. As shown in FIGS. 1 and 2, the casing 1 includes a cylindrical portion 1A, a bottom portion 1B provided on the other axial side of the cylindrical portion 1A, and a cylindrical portion having a large diameter at the center of the bottom portion 1B. From the formed bearing mounting portion 1C, three boss portions 1D (see FIG. 6) provided on the bottom portion 1B at positions surrounding the bearing mounting portion 1C, to which an auxiliary crank 7 described later is mounted, and the bottom portion 1B. It is generally constituted by an attachment frame portion 1E that protrudes outward and to which a fan cover 21 described later is attached. In addition, FIG. 1 has shown the figure seen irregularly from the arrow I-I direction in FIG. 3 so that the flow of air may be visualized.

  Here, the bearing mounting portion 1 </ b> C projects larger than the boss portions 1 </ b> D from the bottom portion 1 </ b> B of the casing 1 toward the fan cover 21. Further, the mounting frame portion 1E is formed as a frame-shaped protrusion having a shape corresponding to the opening 21A of the fan cover 21. Moreover, the outer surface located in the other axial direction side (fan cover 21 side) of the casing 1 is the back surface 1F.

  On the other hand, as shown in FIG. 3, an inflow port 1G into which cooling air flows and an outflow port 1H from which cooling air flows out are provided on the opening side of the cylindrical portion 1A. It has been. The inflow port 1G and the outflow port 1H are open on both sides in the diametrical direction with a revolving scroll 3 (the revolving scroll side air passage 25) described later interposed therebetween.

  Reference numeral 2 denotes a fixed scroll provided on the opening side of the casing 1, and the fixed scroll 2 closes the opening side of the cylindrical portion 1A. As shown in FIG. 1, the fixed scroll 2 includes an end plate 2A formed in a substantially disc shape, a spiral wrap portion 2B erected in the axial direction on the surface of the end plate 2A, and the wrap portion 2B. The short cylindrical portion 2 </ b> C formed so as to surround and a plurality of radiating fins 2 </ b> D erected on the back surface of the end plate 2 </ b> A.

  3 is a orbiting scroll provided in the casing 1 so as to be orbitable. As shown in FIGS. 1 to 3, the orbiting scroll 3 includes a substantially disc-shaped end plate 3A facing the end plate 2A of the fixed scroll 2; A spiral wrap portion 3B standing on the surface of the end plate 3A, and a connecting portion 3C standing at the center of the rear surface of the end plate 3A and connected to the main shaft portion 9 of the drive shaft 8 via a swing bearing 12 to be described later. The three boss portions 3D, which are provided on the back side of the end plate 3A at positions surrounding the connecting portion 3C and to which the auxiliary cranks 7 are respectively attached, are roughly constituted.

  Here, a plurality of heat radiation fins 3E are provided on the back surface of the end plate 3A. The connecting portion 3C is formed as a stepped cylindrical boss, for example, and protrudes in the axial direction from the back surface of the end plate 3A toward the drive shaft 8.

  The wrap portion 3B is disposed so as to overlap with the wrap portion 2B of the fixed scroll 2 while being shifted by a predetermined angle, and a plurality of compression chambers 4 are defined between the wrap portions 2B and 3B. . Each compression chamber 4 is continuously reduced between the wrap portions 2B and 3B when the orbiting scroll 3 performs the orbiting motion, and compresses while sucking outside air from the suction port 5 (see FIG. 10) on the outer peripheral side. The discharged air is discharged to the outside from the discharge port 6 at the center.

  Reference numeral 7 denotes, for example, three auxiliary cranks provided as an anti-rotation mechanism provided between the casing 1 and the orbiting scroll 3, and these auxiliary cranks 7 prevent the rotation of the orbiting scroll 3 when the orbiting scroll 3 performs an orbiting motion. To do. Here, as shown in FIGS. 1 and 3, the auxiliary crank 7 is attached to a shaft member 7A bent in a crank shape, and the shaft member 7A rotatably attached to the casing 1 and the boss portions 1D and 3D of the orbiting scroll 3, respectively. It is comprised by several bearing 7B.

  Reference numeral 8 denotes a drive shaft that is rotatably provided on the casing 1 via main bearings 10 and 11 to be described later. The drive shaft 8 is driven to rotate by a motor 15 so as to turn the orbiting scroll 3. It is. The drive shaft 8 includes a main shaft portion 9 and a joint portion 13 which will be described later.

  Reference numeral 9 denotes a stepped cylindrical main shaft portion 9 that constitutes a main body portion of the drive shaft 8, and the main shaft portion 9 is formed as a substantially cylindrical body whose one side in the axial direction is expanded in a stepped shape as shown in FIG. 2. The main bearings 10 and 11 are rotatably supported.

  In addition, an eccentric hole 9 </ b> A composed of a bottomed circular hole opened toward the orbiting scroll 3 is provided on one side in the axial direction of the main shaft portion 9, and the eccentric hole 9 </ b> A is located with respect to the rotational axis of the drive shaft 8. It is eccentric in the radial direction by a predetermined dimension. A connecting portion 3C of the orbiting scroll 3 is rotatably fitted in the eccentric hole 9A via an orbiting bearing 12 described later. For this reason, when the drive shaft 8 rotates, the orbiting scroll 3 orbits around the rotation axis.

  Reference numerals 10 and 11 denote, for example, two main bearings provided in the bearing mounting portion 1 </ b> C of the casing 1, and these main bearings 10 and 11 are constituted by, for example, grease-filled deep groove ball bearings or the like. The part 9 is rotatably supported.

  Reference numeral 12 denotes an orbiting bearing provided in the eccentric hole 9A of the main shaft portion 9. The orbiting bearing 12 is constituted by, for example, a cylindrical roller bearing or the like, and is fitted to the outer periphery of the distal end of the connecting portion 3C of the orbiting scroll 3. Thereby, the turning bearing 12 has connected the main-shaft part 9 and the connection part 3C so that turning is possible.

  Reference numeral 13 denotes a joint portion that constitutes a part of the drive shaft 8, and the joint portion 13 is a cylindrical coupling that connects the output shaft 15B of the motor 15 and the main shaft portion 9, as shown in FIGS. These are formed and rotated together. Here, the main shaft portion 9 and the output shaft 15B are inserted into the inner peripheral side of the joint portion 13 from opposite directions, and their rotation is restricted by the key 14.

  Reference numeral 15 denotes a motor as a drive source provided in the casing 1 via a fan cover 21 described later. The motor 15 rotates and drives the drive shaft 8 and the cooling fan 19 together. Here, as shown in FIGS. 1 and 11, the motor 15 includes a substantially cylindrical motor case 15A, an output shaft 15B rotatably provided on the motor case 15A, and a stator fixed in the motor case 15A. 15C and a rotor 15D fixed to the outer peripheral side of the output shaft 15B are roughly configured.

  Further, the motor case 15A is provided with, for example, three protrusions 15E (only two are shown) protruding toward the mounting seats 21E of the fan cover 21. These protrusions 15E are joined (abutted) to each mounting seat 21E of the fan cover 21 via a heat insulating material 31 to be described later, and in this state, are fastened to the mounting seat 21E together with the heat insulating material 31 by the mounting screws 16. Has been.

  Thus, the motor 15 is attached to the fan cover 21 using each protrusion 15E. In this state, an axial gap corresponding to the protruding dimension of the protrusion 15E is formed between the motor case 15A and the fan cover 21, and this gap is cooled as shown by an arrow A in FIG. A fan-side intake port 17 that sucks outside air into the fan cover 21 when the fan 19 is operated.

  The motor case 15 </ b> A is provided with a plurality of motor-side intake ports 18 that are located on the opposite side of the fan-side intake port 17 in the axial direction. As shown by arrow B, these motor side air intakes 18 suck outside air (cooling air) into the motor case 15A when the cooling fan 19 is operated, and this cooling air passes through the motor case 15A. It is sucked into the fan cover 21.

  Reference numeral 19 denotes a cylindrical cooling fan provided in the joint portion 13 of the drive shaft 8, and the cooling fan 19 is composed of, for example, a centrifugal fan as shown in FIGS. 1 and 4. 15 and is accommodated in the fan cover 21.

  The cooling fan 19 rotates together with the drive shaft 8 to blow out the air sucked into the inner peripheral side from the outer peripheral side, thereby generating cooling air in the duct 20 and the motor 15 described later. It is. At this time, the cooling fan 19 also generates cooling air in the vicinity of an outflow side opening 29 described later, thereby applying a negative pressure to the outflow side opening 29.

  A duct 20 is provided surrounding the casing 1 and the cooling fan 19. The duct 20 guides the cooling air generated by the cooling fan 19 to the back side of the fixed scroll 2 and the orbiting scroll 3. The duct 20 includes a fan cover 21 and a scroll cover 23 which will be described later.

  A fan cover 21 is disposed between the back surface 1F of the casing 1 and the motor 15 and extends in the axial direction surrounding the cooling fan 19 as shown in FIG. As shown in FIGS. 4 and 11, the fan cover 21 has an opening portion 21 </ b> A that is attached to the mounting frame portion 1 </ b> E of the casing 1, and a casing that is continuous from the opening portion 21 </ b> A. A connection port 21 </ b> B that extends outward in the radial direction of 1 and to which the side cover portion 23 </ b> A of the scroll cover 23 is connected is provided.

  Further, on the other side in the axial direction of the fan cover 21, a bottom portion 21C is provided as shown in FIG. The bottom 21C has a circular suction hole 21D that opens toward the inner peripheral side of the cooling fan 19, and projects from the bottom 21C to the back side at a position that surrounds the suction hole 21D. For example, three mounting seats 21 </ b> E constituting the end of the motor 15 side) are provided.

  The fan cover 21 has the opening 21 </ b> A in contact with the mounting frame portion 1 </ b> E of the casing 1 through the heat insulating cover 30 described later, and the casing 1 together with the heat insulating cover 30 by, for example, a plurality of mounting screws 22. It is fastened to.

  Reference numeral 23 denotes a scroll cover provided on the casing 1. The scroll cover 23 is formed as a substantially U-shaped frame, for example, as shown in FIGS. 1 and 10, and extends along the outer peripheral side of the casing 1 and the fixed scroll 2. A side cover portion 23A extending in the axial direction and a flat plate-like back cover portion 23B provided on the back surface side of the fixed scroll 2 and covering each radiation fin 2D.

  As shown in FIG. 4, the side cover portion 23 </ b> A is connected to the connection port 21 </ b> B of the fan cover 21 at the base end side and extends to the position of the back cover portion 23 </ b> B. Thereby, the front end side of the duct 20 is connected to a fixed scroll side air passage 24 and an orbiting scroll side air passage 25 which will be described later.

  Reference numeral 24 denotes a fixed scroll side air passage provided on the back side of the fixed scroll 2, and the fixed scroll side air passage 24 is provided between the fixed scroll 2 and the back cover portion 23B of the scroll cover 23 as shown in FIG. Is formed.

  Reference numeral 25 denotes an orbiting scroll side air passage provided on the back side of the orbiting scroll 3, and the orbiting scroll side air passage 25 is located in the casing 1 and is formed between the bottom portion 1 </ b> B and the orbiting scroll 3. Between the inflow port 1G and the outflow port 1H. Further, in the orbiting scroll side air passage 25, a connecting portion 3C, a boss portion 3D, a radiating fin 3E, each auxiliary crank 7 of the orbiting scroll 3 and an inflow side opening 28 described later are arranged.

  When the cooling fan 19 is operated, the cooling air sucked into the fan cover 21 is blown to the scroll cover 23 side. This cooling air circulates in the fixed scroll side air passage 24 along the radiation fins 2D as shown by an arrow C in FIG. 1, and also radiates heat in the orbiting scroll side air passage 25 as shown by an arrow D. It distribute | circulates along the fin 3E and becomes a structure which cools each scroll 2,3, the auxiliary | assistant crank 7, etc. FIG.

  Next, a cooling structure provided in the connecting portion 3C of the orbiting scroll 3 and the drive shaft 8 will be described.

  First, reference numeral 26 denotes a cooling air passage provided in the main shaft portion 9 of the drive shaft 8, and the cooling air passage 26 mainly includes the main shaft portion 9, the main main portion 9, and the like through the passage of a part of the cooling air flowing through the casing 1. The bearings 10 and 11 are cooled. Here, as shown in FIG. 2, the cooling air passage 26 is formed by a through hole penetrating the main shaft portion 9 in the axial direction, and extends in the axial direction through the inner peripheral side of the main bearing 10. One end side of the cooling air passage 26 opens at the bottom surface of the eccentric hole 9 </ b> A, and the other end side opens at the end surface of the main shaft portion 9.

  Reference numeral 27 denotes an auxiliary cooling air passage provided in the connecting portion 3C of the orbiting scroll 3. The auxiliary cooling air passage 27 mainly distributes the cooling air toward the cooling air passage 26, thereby mainly connecting the connecting portion 3C and the orbiting bearing 12. Etc. are cooled.

  Here, the auxiliary cooling air passage 27 is formed as a bottomed hole in which one side in the axial direction (the end plate 3A side) is closed, and extends in the axial direction through the inner peripheral side of the swivel bearing 12. The other side of the auxiliary cooling air passage 27 in the axial direction opens at the tip end surface of the connecting portion 3C in the eccentric hole 9A of the main shaft portion 9, and even when the orbiting scroll 3 is orbiting, the cooling air passage 26 and Always kept in communication.

28 shows a plurality provided the flow entry side opening in the connecting portion 3C of the orbiting scroll 3, these inlet-side opening 28, Fig. 2, as shown in FIG. 3, from one axial side of the auxiliary cooling air passage 27 It is formed extending in the radial direction, and is open to the outer peripheral surface of the connecting portion 3C at a position closer to the back surface side of the end plate 3A than the main bearings 10 and 11, respectively. In this case, the inflow side opening 28 is formed so as to be inclined obliquely between the radiation fins 3E of the orbiting scroll 3 in consideration of, for example, workability at the time of drilling.

  The inflow side opening 28 opens the auxiliary cooling air passage 27 to the outer peripheral surface of the connecting portion 3 </ b> C and communicates with the cooling air passage 26 through the auxiliary cooling air passage 27. Thereby, when the cooling fan 19 is operated, a part of the cooling air flowing along the rear surface side of the end plate 3A flows into the inflow side opening 28 as shown by an arrow P in FIG. The cooling air passage 26 is circulated through the air passage 27.

29 shows the flow exit side opening provided in the joint portion 13 of the drive shaft 8, the outflow-side opening 29, Fig. 2, as shown in FIG. 9, is formed through the joint portion 13 in the radial direction . The radially inner side of the outflow side opening 29 opens between the output shaft 15B of the motor 15 and the main shaft portion 9 of the drive shaft 8, and is disposed in the vicinity of the opening end of the cooling air passage 26. Further, the radially outer side of the outflow side opening 29 opens to the inner peripheral side (suction side) of the cooling fan 19.

  As a result, a negative pressure is generated in the outflow side opening 29 due to the suction operation of the cooling fan 19, so that the cooling air flowing in the cooling air passage 26 flows from the outflow side opening 29 as shown by an arrow Q in FIG. The cooling air flows out to the outside, and new cooling air flows into the cooling air passage 26 from the inflow side opening 28.

  In this case, the outflow side opening 29 is opened on the opposite side of the inflow side opening 28 in the axial direction with the main bearings 10 and 11 and the slewing bearing 12 interposed therebetween, and the cooling air passage 26 and the opening 28 are formed between these openings 28 and 29. An auxiliary cooling air passage 27 is disposed. For this reason, the cooling air flowing through the cooling air passages 26 and 27 efficiently cools the main shaft portion 9 of the drive shaft 8, the connecting portion 3C of the orbiting scroll 3, and the like on the inner peripheral side of the three bearings 10, 11, and 12. These bearings 10-12 can be kept at a low temperature.

  Next, a heat insulating structure provided between the casing 1 and the fan cover 21 and between the fan cover 21 and the motor 15 will be described.

  First, reference numeral 30 denotes a heat insulating cover provided between the back surface 1F of the casing 1 and the fan cover 21. The heat insulating cover 30 is heated from the casing 1 with respect to the fan cover 21 and the cooling air flowing through the inside. Suppresses conduction. The heat insulating cover 30 prevents the casing 1 disposed in the vicinity of the cooling fan 19 from being cooled more strongly than the orbiting scroll 3.

  Here, as shown in FIGS. 5 to 7, the heat insulating cover 30 is formed in a plate shape or a sheet shape by a material having heat insulating properties such as resin, rubber, etc., and the mounting frame portion 1 </ b> E of the casing 1 (of the fan cover 21). It has an outer shape corresponding to the opening 21A). And the peripheral part of the heat insulation cover 30 is clamped between the said attachment frame part 1E and the opening part 21A, and is fixed with the attachment screw 22 in this state.

  Further, as shown in FIGS. 1 and 4, the inner part of the heat insulating cover 30 is located in the fan cover 21 and is disposed between the back surface 1F of the casing 1 and the cooling fan 19, and the bottom 1B of the casing 1 and the boss. Covers part 1D and the like. In this case, a fitting hole 30 </ b> A (see FIG. 5) into which the bearing mounting portion 1 </ b> C of the casing 1 is fitted is provided in the vicinity of the center of the heat insulating cover 30.

  As described above, the heat insulating cover 30 is interposed at the abutting portion between the casing 1 and the fan cover 21, and shields the back surface 1 </ b> F of the casing 1 from the outlet side of the cooling fan 19 within the fan cover 21.

  On the other hand, 31 indicates, for example, three heat insulating materials provided between the back side of the fan cover 21 and the motor 15. These heat insulating materials 31 prevent heat generated when the motor 15 is operated from being conducted to the fan cover 21.

  Here, as shown in FIGS. 1 and 11, the heat insulating material 31 is formed as a plate-shaped small piece of a heat-insulating material such as resin or rubber, and is attached to the mounting seat 21 </ b> E (the protrusion of the motor 15) of the fan cover 21. 15E).

  And the heat insulating material 31 is clamped between the said mounting seat 21E and the projection part 15E, and is being fixed with the attachment screw 16 in this state. As described above, the heat insulating material 31 is interposed at the joint portion (abutting portion) between the fan cover 21 and the motor 15.

  The scroll type air compressor according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  First, during operation of the compressor, when the drive shaft 8 is rotationally driven by the motor 15, this rotation is converted into a turning motion by the eccentric hole 9 </ b> A of the main shaft portion 9. Thereby, the orbiting scroll 3 orbits with respect to the fixed scroll 2 in a state where the rotation is restricted by each auxiliary crank 7.

  When the orbiting scroll 3 is orbited, the compression chamber 4 is continuously reduced between the wrap portion 3B and the lap portion 2B of the fixed scroll 2, and each compression chamber 4 receives the air sucked from the suction port 5. Compressed air is discharged from the discharge port 6 toward an external air tank (not shown) or the like while sequentially compressing.

  On the other hand, during the compression operation, the cooling fan 19 is also rotationally driven by the motor 15. When the cooling fan 19 rotates, the outside air is sucked in the direction indicated by the arrow A from the fan-side intake port 17 as shown in FIG. 1, and cooling air is generated in the fan cover 21. In addition, due to the suction operation of the cooling fan 19, the outside air is also sucked in the direction of arrow B from the motor side air inlet 18 to become cooling air, which cools the components in the motor 15 and then flows into the fan cover 21. To do.

  Then, the cooling air generated in the fan cover 21 is guided by the duct 20, and a part of the cooling air flows through the fixed scroll side air passage 24 as indicated by an arrow C to cool the fixed scroll 2. The remaining cooling air flows from the inlet 1G of the casing 1 into the orbiting scroll side air passage 25 as shown by an arrow D, and the end plate 3A, the connecting portion 3C, the boss portion 3D, and the auxiliary cranks of the orbiting scroll 3 are provided. After cooling 7 etc., it flows out from the outlet 1H.

  Further, when the cooling fan 19 rotates, a negative pressure generated on the suction side acts on the outflow side opening 29. As a result, a part of the cooling air flowing through the orbiting scroll side air passage 25 is sucked in the direction indicated by the arrow P from the inflow side opening 28 as shown in FIG. The cooling air flows through the cooling air passages 26 and 27 to cool the connecting portion 3C of the orbiting scroll 3, the main shaft portion 9 of the drive shaft 8, etc. 29 flows out.

  For this reason, even if heat is generated on each compression chamber 4 side by the compression operation, this heat is transmitted to the main bearings 10 and 11 and the orbiting bearing 12 via the connecting portion 3C of the orbiting scroll 3 and the main shaft portion 9 of the drive shaft 8. It is possible to suppress transmission.

  On the other hand, during the compression operation, heat is conducted from the compression chamber 4 side to the casing 1 and the motor 15 also generates heat. However, since the heat is suppressed from being transmitted to the fan cover 21 by the heat insulating cover 30 and the heat insulating material 31, the fan cover 21 and the cooling air flowing in the fan cover 21 can be kept at a low temperature.

  Further, when the cooling air generated in the fan cover 21 directly contacts the casing 1, the casing 1 is cooled more strongly than the orbiting scroll 3, and a large temperature difference (that is, thermal deformation) between the casing 1 and the orbiting scroll 3. A difference in amount) may occur, and parts such as the auxiliary crank 7 are easily affected by this.

  However, since the back surface 1F of the casing 1 is shielded from the blowout side of the cooling fan 19 by the heat insulating cover 30, the variation in the cooling state between the casing 1 and the orbiting scroll 3 can be suppressed, and these thermal expansions The difference in quantity can be made sufficiently small.

  Thus, according to the present embodiment, the main shaft portion 9 of the drive shaft 8 is provided with the cooling air passage 26, and the connecting portion 3 </ b> C of the orbiting scroll 3 is provided with the auxiliary cooling air passage 27 and the inflow side opening 28. Since the joint portion 13 of the shaft 8 is provided with the outflow side opening 29, the inflow side opening 28 and the outflow side opening 29 are opened on both sides in the axial direction with the main bearings 10 and 11 and the swivel bearing 12 interposed therebetween. Can be made.

  Thus, the cooling air can be circulated from the inflow side opening 28 toward the outflow side opening 29 in the cooling air passages 26, 27 at positions on the inner peripheral side of the main bearings 10, 11 and the swivel bearing 12. In addition, the connecting portion 3C of the orbiting scroll 3, the main shaft portion 9 of the drive shaft 8, the bearings 10 to 12, and the like can be efficiently cooled by the cooling air.

  Therefore, for example, even if only the cooling air passages 26 and 27 having the minimum flow passage area are provided, it is possible to reliably suppress the compression heat generated on the orbiting scroll 3 side from being transmitted to the main bearings 10 and 11 or the orbiting bearing 12. The bearings 10 to 12 can be kept at a low temperature.

  Accordingly, the life of the lubricant that lubricates the bearings 10 to 12 can be extended without providing a large-diameter space or the like in the main shaft portion 9 or in the connecting portion 3C. 12 can be reliably protected from deterioration due to heat. As described above, the heat resistance can be enhanced while sufficiently securing the strength of the drive shaft 8.

  Further, since the inflow side opening 28 is arranged at a position closer to the back side of the orbiting scroll 3 than the main bearings 10 and 11 (in this embodiment, for example, the connecting portion 3C of the orbiting scroll 3), the cooling fan 19 During operation, the cooling air flowing on the back side of the orbiting scroll 3 can be smoothly introduced from the inflow side opening 28 into the cooling air passage 26. Thereby, the cooling air generated by one cooling fan 19 can be circulated through the fixed scroll side air passage 24, the orbiting scroll side air passage 25, and the cooling air passages 26 and 27.

  For this reason, components such as the scrolls 2 and 3 and the auxiliary crank 7 can be efficiently cooled together while cooling the main shaft portion 9 from the inside by the cooling air of the cooling fan 19. Accordingly, there is no need to provide a dedicated cooling means for cooling the drive shaft 8 from the inside and other cooling means for cooling the inside of the casing 1, so that the entire cooling structure can be simplified.

  Further, since the outflow side opening 29 is arranged on the suction side of the cooling fan 19, a negative pressure can be applied to the vicinity of the outflow side opening 29 when the cooling fan 19 is operated, The flow of cooling air can be efficiently generated by this negative pressure.

  Further, by opening the inflow side opening 28 on the outer peripheral surface of the connecting portion 3C, the auxiliary cooling air passage 27 extending in the axial direction can be easily opened on the outer peripheral side of the connecting portion 3C. It can be done efficiently.

  On the other hand, since the heat insulating cover 30 is provided between the rear surface 1F of the casing 1 and the fan cover 21, the heat generated by the compression scroll generated on the orbiting scroll 3 side is transmitted from the casing 1 to the fan cover 21. This heat can be reliably suppressed from being transmitted to the cooling air flowing through the fan cover 21. Therefore, the fixed scroll 2 and the orbiting scroll 3 can be cooled by the cooling air having a low temperature, and the cooling efficiency thereof can be increased.

  Further, the heat insulating cover 30 can shield the back surface 1 </ b> F of the casing 1 from the cooling fan 19 within the fan cover 21. As a result, since the cooling air does not directly contact the back surface 1F of the casing 1, it is possible to prevent the casing 1 from being cooled more strongly than the orbiting scroll 3, and to bring the cooling states of both closer together.

  Thereby, the amount of thermal deformation of the casing 1 and the orbiting scroll 3 can be made substantially uniform, and parts such as the auxiliary crank 7 disposed between them can be prevented from receiving an unexpected external force due to the difference of the amount of thermal deformation. Can do. Therefore, early wear and distortion of the auxiliary crank 7 can be prevented, and durability can be improved.

  Further, since the heat insulating material 31 is provided between the fan cover 21 and the motor 15, heat generated on the motor 15 side is transmitted to the fan cover 21, and this heat is transmitted to the cooling air flowing in the fan cover 21. Can be reliably suppressed. Therefore, the cooling air can be kept at a low temperature, and the cooling efficiency of the scrolls 2 and 3 can be further increased.

  In the embodiment, the cooling air is circulated in the cooling air passages 26 and 27 from the orbiting scroll 3 toward the cooling fan 19. However, the present invention is not limited to this, and in the cooling air passages 26 and 27, for example, in the case of a full-rotation scroll, the cooling air may be circulated from the cooling fan 19 side toward the orbiting scroll 3. In this case, for example, the inflow side opening 28 on the orbiting scroll 3 side may be used as the outflow side opening, and the outflow side opening 29 on the cooling fan 19 side may be used as the inflow side opening.

  In the embodiment, the cooling fan 19 is formed by a centrifugal fan, and the outflow side opening 29 is opened to the suction side of the cooling fan 19. However, the present invention is not limited to this, and the cooling fan may be configured by, for example, an axial fan, or the outflow side opening 29 may be opened to the outlet side of the cooling fan.

  In the embodiment, the drive shaft 8 is constituted by the main shaft portion 9 and the joint portion 13, the outlet side of the cooling air passage 26 is opened at the end surface of the main shaft portion 9, and the outlet side opening 29 is provided in the joint portion 13. It was set as the structure provided. However, the present invention is not limited to this. For example, the drive shaft 8 may be formed integrally with a metal rod or the like, and the outflow side opening 29 may be provided at an arbitrary position with respect to the length direction of the drive shaft. .

  Furthermore, in the embodiment, a connecting portion 3C is provided on the rear surface side of the orbiting scroll 3, and an eccentric hole 9A is provided in the main shaft portion 9 of the drive shaft 8, and the connecting portion is connected to the eccentric hole 9A via the orbiting bearing 12. It was set as the structure which 3C is fitted. However, the present invention is not limited to this. For example, a cylindrical boss portion is provided on the back surface side of the orbiting scroll 3 and the eccentric shaft portion eccentric from the rotation axis is provided on the end side of the drive shaft 8 as the connecting portion of the present invention. It is good also as a structure which provides and this eccentric shaft part is fitted in a boss | hub part via the turning bearing 12. FIG.

  In this case, the position where the inflow side opening is provided may be the side surface of the boss portion on the side of the orbiting scroll 3 in the axial direction from the orbiting bearing 12 or the side surface of the drive shaft on the motor 15 side of the orbiting bearing 12. Both may be used.

  Furthermore, in the embodiment, two main bearings 10 and 11 concentric with the drive shaft 8 are provided, but the present invention is not limited to this, and for example, one or three may be provided.

  On the other hand, in the embodiment, the scroll type air compressor has been described as an example of the scroll type fluid machine. However, the present invention is not limited to this, and may be applied to other scroll type fluid machines such as a refrigerant compressor for compressing a refrigerant.

It is the longitudinal cross-sectional view which looked at the scroll type air compressor by embodiment of this invention from the arrow I-I direction in FIG. It is a partial expanded sectional view which expands and shows the casing, each scroll, a drive shaft, a cooling fan, etc. in FIG. It is the cross-sectional view which looked at the air compressor from the arrow III-III direction in FIG. It is the cross-sectional view which looked at the air compressor from the arrow IV-IV direction in FIG. It is a left view which shows the state which removed the cooling fan, the fan cover, etc. about the air compressor in FIG. FIG. 6 is a left side view showing the casing in FIG. 5 alone. It is a left view which shows the heat insulation cover in FIG. 5 alone. It is the left view which looked at the fan cover in FIG. 1 from the motor side. It is a principal part expanded sectional view which shows the state before assembling the main-shaft part of a drive shaft, the output shaft of a motor, a cooling fan, etc. It is a disassembled perspective view shown in the state before assembling a casing, a fixed scroll, a turning scroll, etc. It is a disassembled perspective view shown in the state before assembling a casing, a motor, a fan cover, a heat insulation cover, a heat insulating material, etc.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Casing 1E Mounting frame part 1F Back surface 2 Fixed scroll 3 Orbiting scroll 2A, 3A End plate 2B, 3B Lapping part 3C Connection part 4 Compression chamber 5 Suction port 6 Discharge port 7 Auxiliary crank 8 Drive shaft 9 Main shaft part 9A Eccentric hole 10,11 Main bearing 12 Slewing bearing 13 Joint 15 Motor (drive source)
15A Motor Case 15B Output Shaft 15E Protrusion 17 Fan Side Inlet 18 Motor Side Inlet 19 Cooling Fan 20 Duct 21 Fan Cover 21A Opening 21E Mounting Seat (End on Drive Side)
23 scroll cover 24 fixed scroll side air passage 25 orbiting scroll side air passage 26 cooling air passage 27 auxiliary cooling air passage 28 inflow side opening (one opening)
29 Outflow side opening (other openings)
30 Insulation cover 31 Insulation

Claims (6)

A casing, a fixed scroll provided with a spiral wrap portion on the surface of the end plate provided on the casing, and a spiral shape overlapping the wrap portion of the fixed scroll on the surface of the end plate provided in a rotatable manner in the casing. A orbiting scroll in which a lap portion is erected and a connecting portion is provided on the back surface of the end plate, and a rotating scroll is provided in the casing via a main bearing and is connected to a connecting portion of the orbiting scroll via an orbiting bearing. A scroll type fluid machine comprising: a drive shaft configured to rotate; and a drive source for rotating the orbiting scroll by rotationally driving the drive shaft.
The drive shaft is provided with a cooling air passage extending in the axial direction through the inner peripheral side of the main bearing and through which cooling air flows.
An inflow side opening communicating with the cooling air passage is provided so as to open to the outer peripheral side of the connecting portion on the back side of the orbiting scroll from the main bearing,
An outflow side opening communicating with the cooling air passage is provided so as to open on the opposite side to the inflow side opening in the axial direction across the main bearing,
A scroll type fluid machine characterized in that the cooling air flowing through the orbiting scroll side air passage provided on the back side of the orbiting scroll flows in from the inflow side opening and flows out from the outflow side opening. .   The connecting part of the orbiting scroll is a boss protruding to the back side of the end plate, and the connecting part has an auxiliary cooling air passage that communicates with the cooling air passage and extends in the axial direction through the inner peripheral side of the orbiting bearing. The scroll fluid machine according to claim 1, wherein the scroll fluid machine is provided.   The scroll fluid machine according to claim 1 or 2, wherein the drive shaft is provided with a cooling fan that generates cooling air at a position corresponding to the outflow side opening. A casing, a fixed scroll provided with a spiral wrap portion on the surface of the end plate provided on the casing, and a spiral shape overlapping the wrap portion of the fixed scroll on the surface of the end plate provided in a rotatable manner in the casing. A orbiting scroll in which a lap portion is erected and a connecting portion is provided on the back surface of the end plate, and a rotating scroll is provided in the casing via a main bearing and is connected to a connecting portion of the orbiting scroll via an orbiting bearing A scroll type fluid machine comprising: a drive shaft configured to rotate; and a drive source for rotating the orbiting scroll by rotationally driving the drive shaft.
The drive shaft is provided with a cooling air passage extending in the axial direction through the inner peripheral side of the main bearing and through which cooling air flows.
An inflow side opening communicating with the cooling air passage is provided so as to open to the back side of the orbiting scroll from the main bearing,
An outflow side opening communicating with the cooling air passage is provided so as to open on the opposite side to the inflow side opening in the axial direction across the main bearing,
The cooling air flows in from the inflow side opening and flows out from the outflow side opening,
The drive shaft is provided with a cooling fan that generates cooling air at a position corresponding to the outflow side opening,
A scroll type fluid machine characterized in that a heat insulating cover made of a heat insulating material is provided between a back side of the casing and the cooling fan. A casing, a fixed scroll provided with a spiral wrap portion on the surface of the end plate provided on the casing, and a spiral shape overlapping the wrap portion of the fixed scroll on the surface of the end plate provided in a rotatable manner in the casing. A orbiting scroll in which a lap portion is erected and a connecting portion is provided on the back surface of the end plate, and a rotating scroll is provided in the casing via a main bearing and is connected to a connecting portion of the orbiting scroll via an orbiting bearing A scroll type fluid machine comprising: a drive shaft configured to rotate; and a drive source for rotating the orbiting scroll by rotationally driving the drive shaft.
The drive shaft is provided with a cooling fan that rotates with the drive shaft between the back side of the casing and the drive source,
A duct that surrounds the cooling fan and the casing and guides the cooling air to the fixed scroll and the orbiting scroll is provided,
A scroll type fluid machine, characterized in that a heat insulating cover formed of a heat insulating material is provided between the rear side of the casing and the cooling fan located in the duct. The drive shaft is provided with a cooling air passage that extends in the axial direction through the inner peripheral side of the main bearing and through which cooling air flows, and an inflow side opening that communicates with the cooling air passage is provided at the connecting portion of the orbiting scroll. 6. The scroll fluid machine according to claim 5 , wherein the drive shaft is provided with an outflow side opening that opens on the opposite side of the inflow side opening in the axial direction across the main bearing.

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