CN113646535A

CN113646535A - Two-stage reciprocating compressor

Info

Publication number: CN113646535A
Application number: CN201980086554.9A
Authority: CN
Inventors: E·布雷德尔; T·格林沃德
Original assignee: Nabtesco Automotive Corp
Current assignee: Nabtesco Automotive Corp
Priority date: 2018-12-27
Filing date: 2019-12-25
Publication date: 2021-11-12
Anticipated expiration: 2039-12-25
Also published as: JP7548821B2; CN113646535B; CN117307444A; WO2020138129A1; JPWO2020138129A1; EP3904684B1; EP3904684A1; EP3904684A4

Abstract

A reciprocating compressor according to an aspect of the present invention includes: a rotation drive source housed in the case; an output shaft that outputs rotation from the rotary drive source and is provided in such a manner that one end thereof protrudes from an end surface of the housing, the output shaft extending in an axial direction; a low-pressure compression element that compresses air using a rotational driving force from the output shaft as a power source; an intercooler that cools the compressed air discharged from the low-pressure compression element; a high-pressure compression element that further compresses the compressed air cooled by the intercooler using a rotational driving force from the motor output shaft as a power source; and a blower fan connected to the output shaft and disposed between the end surface of the housing and the intercooler in the axial direction.

Description

Two-stage reciprocating compressor

Technical Field

The present invention relates to a two-stage reciprocating compressor.

Background

There is known a two-stage reciprocating compressor which compresses air in two stages in order to obtain compressed air of high pressure. A two-stage reciprocating compressor has a low pressure side cylinder and a high pressure side cylinder. In the two-stage reciprocating compressor, air compressed by the low-pressure side cylinder is sent to the high-pressure side cylinder, where it is further compressed. The compressed air compressed in the high-pressure side cylinder is supplied to the air compressor via the discharge port. When the two-stage reciprocating compressor is mounted on a commercial vehicle, compressed air discharged from a high-pressure side cylinder head is supplied to, for example, a brake or an air suspension. A conventional two-stage reciprocating compressor is disclosed in japanese patent application laid-open No. 2013-040586.

Since compression heat is generated in the air compression step, the temperatures of the cylinder and the piston rise during the operation of the reciprocating compressor. In addition, since the electric motor is driven by an applied current, joule heat is generated by the applied current. This also increases the temperature of the electric motor. Therefore, the conventional reciprocating compressor is often provided with a cooling fan. Two-stage reciprocating compressors provided with a cooling fan are disclosed in japanese patent laid-open nos. 9-264253 and 2016-070233.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2013-040586

Patent document 2: japanese laid-open patent publication No. 9-264253

Patent document 3: japanese patent laid-open publication No. 2016-070233

Disclosure of Invention

Problems to be solved by the invention

Further improvement in cooling effect is required in a two-stage reciprocating compressor provided with a cooling fan.

One of the objects of the present disclosure is to improve the cooling effect in a two-stage reciprocating compressor. Objects of the present disclosure other than the above objects can be understood by referring to the entire description of the present specification.

Means for solving the problems

A two-stage reciprocating compressor according to an aspect of the present invention includes: a rotation drive source housed in the case; an output shaft that outputs rotation from the rotary drive source and is provided in such a manner that one end thereof protrudes from an end surface of the housing, the output shaft extending in an axial direction; a low-pressure compression element that compresses air using a rotational driving force from the output shaft as a power source; an intercooler that cools the compressed air discharged from the low-pressure compression element; a high-pressure compression element that further compresses the compressed air cooled by the intercooler using a rotational driving force from the motor output shaft as a power source; and a blower fan connected to the output shaft and disposed between the end surface of the housing and the intercooler in the axial direction.

In one aspect of the present invention, the housing has a plurality of ribs extending in the axial direction on an outer surface thereof.

In one aspect of the present invention, the housing has a plurality of other ribs extending in a direction perpendicular to the axial direction.

The two-stage reciprocating compressor according to an aspect of the present invention further includes a muffler that supplies the air to the low-pressure compression element.

The two-stage reciprocating compressor according to an aspect of the present invention further includes a cover that covers at least a part of the casing, the low-pressure compression element, the intercooler, the high-pressure compression element, and the blower fan in a large number.

One aspect of the present invention relates to an automobile. The automobile is provided with the two-stage reciprocating compressor.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the embodiments of the present invention, the cooling effect in the two-stage reciprocating compressor can be improved.

Drawings

Fig. 1 is a perspective view schematically showing a two-stage reciprocating compressor according to an embodiment.

Fig. 2 is a schematic side view of the two-stage reciprocating compressor of fig. 1.

Fig. 3 is a sectional view schematically showing a section taken along line a-a of the two-stage reciprocating compressor of fig. 2.

Fig. 4 is a perspective view schematically showing a two-stage reciprocating compressor according to another embodiment.

Fig. 5 is a schematic cross-sectional view of other embodiments of a two-stage reciprocating compressor.

Detailed Description

A two-stage reciprocating compressor 1 according to various embodiments of the present invention will be described with reference to fig. 1 to 3. Fig. 1 is a perspective view schematically showing a two-stage reciprocating compressor 1 according to an embodiment of the present invention, fig. 2 is a schematic side view of the two-stage reciprocating compressor 1 of fig. 1, and fig. 3 is a cross-sectional view schematically showing a cross section of the two-stage reciprocating compressor 1 taken along the line a-a of fig. 2. In the present specification, when the up-down direction is referred to, the up-down direction shown in fig. 1 is taken as a reference except for the case where the logical property is specifically referred to in the foregoing and following. In the case where the front-rear direction is mentioned in the present specification, the front-rear direction shown in fig. 2 is taken as a reference except for the case where the front-rear direction is logically particularly mentioned later. Fig. 2 shows an axis C that coincides with a central axis of a crankshaft described later. The axis C extends in the front-rear direction. In the present specification, a direction along the axis C is sometimes referred to as an axial direction, and a direction extending perpendicularly from the axis C is sometimes referred to as a radial direction.

As shown in fig. 1, the two-stage reciprocating compressor 1 includes a casing 10. The housing 10 has a motor case 11, a crankcase 12, a 1 st cylinder 13a, and a 2 nd cylinder 13 b. The 1 st cylinder 13a and the 2 nd cylinder 13b are respectively provided on the upper side of the crankcase 12. 4 leg portions are attached to the lower surface of the housing 10 via the support portion 19. The two-stage reciprocating compressor 1 is installed at a desired installation site via the leg portion 18.

A plurality of 1 st ribs 11a extending in the axial direction and a 2 nd rib 11b extending in the vertical direction are provided on the outer surface of the motor housing 11. The upper end of the 2 nd rib 11b is connected to the rear end of the corresponding 1 st rib 11 a. Some of the 1 st ribs 11a extend from the rear end to the front end of the motor housing 11, and the remaining 1 st ribs 11a extend forward from the rear end of the motor housing 11 and are connected to the 2 nd ribs 11b in the middle.

An internal space penetrating the interior of the motor housing 11 along the axis C is formed in the motor housing 11. The motor housing 11 has a substantially hollow cylindrical shape. A motor 22 is disposed in the internal space of the motor housing 11. The motor 22 has: a stator coil 22a attached to an inner wall of the motor housing 11; a rotor 22b that is mounted on the radially inner side of the stator coil 22 a; and a motor rotation shaft 22c that rotates together with the rotor 22 b. The motor 22 may also include a rotation detection sensor that detects the rotational position of the rotor 22 b. The through hole of the motor housing 11 is closed at the rear end by a rear cover 23. Thereby, the rear surface of the rear cover 23 becomes the rear end surface 11c of the motor housing 11. A through hole connecting the inner space and the outer space of the motor housing 11 is provided at the radial center of the rear cover 23. The motor rotation shaft 22c extends to the outside of the housing 10 through a through hole provided to the rear cover 23. The motor rotating shaft 22c is rotatably supported with respect to the motor housing 11 via a bearing.

A blower fan 24 is attached to a rear end of the motor rotary shaft 22c projecting rearward from the motor housing 11. The blower fan 24 rotates about the center axis C together with the motor rotation shaft 22C. Due to the rotation of the blower fan 24, an airflow fi flowing from the axial rear side of the blower fan 24 toward the fan and an airflow fo flowing from the front side of the blower fan 24 in the axial direction on the outer surface of the casing 10 are generated.

An internal space penetrating the interior of the crankcase 12 along the axis C is formed in the crankcase 12. The internal space of the crankcase 12 and the internal space of the motor housing 11 are partitioned by a partition wall 20. The through hole provided to the crankcase 12 is closed at its front end by a front side cover 21. The front cover 21 includes a substantially disk-shaped cover main body 21a and a dome 21b projecting forward at the center in the radial direction of the cover main body 21 a.

A crankshaft mechanism is disposed in the internal space of the crankcase 12. The crank mechanism has a crankshaft 15. The crankshaft 15 extends along the center axis C inside the crankcase 12 and the motor housing 11. The crankshaft 15 is supported at its front end by a front side cover 21. The crankshaft 15 enters the motor case 11 through a through hole provided in the partition wall 20, and is supported by the inner peripheral surface of a hollow motor rotating shaft 22c in the motor case 11. The crankshaft 15 is attached to the motor rotation shaft 22C so as to rotate around the center axis C together with the motor rotation shaft 22C. Thereby, the rotational driving force from the motor 22 is transmitted to the crankshaft 15 via the motor rotating shaft 22 c.

The crankshaft 15 has a 1 st eccentric portion 15a and a 2 nd eccentric portion 15b provided at a position further to the rear side in the axial direction than the 1 st eccentric portion 15 a. The 1 st eccentric portion 15a and the 2 nd eccentric portion 15b have circular shapes in cross section viewed in a cross section perpendicular to the axis C. The center of the eccentric portion 15a is eccentric with respect to the axis C. The 1 st eccentric portion 15a is connected to a 1 st piston 16a via a 1 st connecting rod 14 a. Similarly, a 2 nd piston 16b is connected to the 2 nd eccentric portion 15b via a 2 nd connecting rod 14 b. The rotational motion of the crankshaft 15 is converted by the 1 st connecting rod 14a into the reciprocating motion of the 1 st piston 16a, and by the 2 nd connecting rod 14b into the reciprocating motion of the 2 nd piston 16 b. Thus, the 1 st piston 16a reciprocates inside the 1 st cylinder 13a, and the 2 nd piston 16b reciprocates inside the 2 nd cylinder 13 a.

The 1 st eccentric portion 15a and the 2 nd eccentric portion 15b have different phases from each other. For example, the phase of the 1 st eccentric portion 15a and the phase of the 2 nd eccentric portion 15b are deviated from each other by 180 °. Due to this phase shift, when the 1 st piston 16a is driven in a direction to compress the cylinder chamber of the 1 st cylinder 13a, the 2 nd piston 16b is driven in a direction to expand the cylinder chamber of the 2 nd cylinder 13 b. On the other hand, when the 2 nd piston 16b is driven in a direction to compress the cylinder chamber of the 2 nd cylinder 13b, the 1 st piston 16a is driven in a direction to expand the cylinder chamber of the 1 st cylinder 13 a.

A 1 st cylinder head 17a is provided at the leading end of the 1 st cylinder 13a, and a 2 nd cylinder head 17b is provided at the leading end of the 2 nd cylinder 13 b. The 1 st cylinder head 17a has an intake port 27a for taking in air into its internal space and an exhaust port 27b for ejecting compressed air. The internal space of the 1 st cylinder head 17a is divided into a suction chamber and a discharge chamber by a partition wall. The air flowing into the intake chamber from the outside of the 1 st cylinder head 17a through the intake port 27a is sucked into the 1 st cylinder 13a, compressed by the 1 st piston 16a reciprocating in the cylinder 13a, and then discharged into the discharge chamber. The compressed air is introduced from the exhaust port 27b of the 1 st cylinder head 17a into the intercooler 25 through the pipe 26a, is cooled by the intercooler 25, and then is introduced into the 2 nd cylinder head 17b through the pipe 26 b. The 2 nd cylinder head 17b has an intake port 28a for taking in compressed air from the pipe 26b and an exhaust port (not shown) for discharging compressed air compressed in the second stage in the 2 nd cylinder 13 b. The air flowing into the 2 nd cylinder head 17b through the intake port 28a is sucked into the 2 nd cylinder 13b, subjected to the second-stage compression by the 1 st piston 16b reciprocating in the cylinder 13b, and then discharged to the outside of the 2 nd cylinder head 17b through the exhaust port. The compressed air compressed in two stages by the 2 nd cylinder 13b can be supplied to various air compression machines not shown. The air compressor machine includes various devices that operate using compressed air. When the two-stage reciprocating compressor 1 is mounted on a commercial vehicle, the compressed air from the 2 nd cylinder 13b can be supplied to, for example, an air brake, an air suspension, and various air-powered machines mounted on commercial vehicles other than these.

In this way, in the two-stage reciprocating compressor 1, the air introduced from the outside is subjected to the first-stage compression in the 1 st cylinder 13a and the second-stage compression in the 2 nd cylinder 13 b. In this way, the 1 st cylinder 13a is a cylinder for low pressure, and the 2 nd cylinder 13b is a cylinder for high pressure. In the present specification, the 1 st cylinder 13a may be referred to as a low-pressure compression element, and the 2 nd cylinder 13b may be referred to as a high-pressure compression element. The low-pressure compression element may include the 1 st piston 16a and the 1 st cylinder head 17 a. The high-pressure compression element may include a 2 nd piston 16b and a 2 nd cylinder head 17 b.

As shown in fig. 3, the intercooler 25 is provided axially rearward of the blower fan 24. In other words, the blower fan 24 is provided between the intercooler 25 and the rear end surface of the motor housing 11. The intercooler 25 is attached to the motor housing 11 by, for example, bolts not shown.

The intercooler 25 is connected to an exhaust port 27b of the 1 st cylinder head 17a via a pipe 26a, and is connected to an intake port 28a of the 2 nd cylinder head 17b via a pipe 26 b. The intercooler 25 includes a meandering pipe connecting the pipe 26a and the pipe 26b, and a plurality of fins provided to the pipe. High-temperature compressed air compressed in the 1 st cylinder 13a is supplied from the pipe 26a to the pipe of the intercooler 25. As described above, the airflow fi flows as the blower fan 24 rotates, and the airflow passes through the intercooler 25. This airflow fi flows along the outer surface of the pipe of the intercooler 25 and the outer surface of the fin, and thus the compressed air passing through the interior of the intercooler 25 is cooled.

Next, the operation of the two-stage reciprocating compressor 1 will be described. When a current is applied to the stator coil 22a, the rotor 22b rotates relative to the stator coil 22 a. At this time, the rotation of the rotor 22b is transmitted to the crankshaft 15 and the blower fan 24 via the motor rotation shaft 22 c. The rotational motion of the crankshaft 15 is converted by the 1 st connecting rod 14a into the reciprocating motion of the 1 st piston 16a, and by the 2 nd connecting rod 14b into the reciprocating motion of the 2 nd piston 16 b. By the reciprocating motion of the 1 st piston 16a and the 2 nd piston 16b, the air introduced from the outside is subjected to the first-stage compression in the 1 st cylinder 13a and the second-stage compression in the 2 nd cylinder 13 b. The air compressed in the 1 st cylinder 13a is cooled by the intercooler 25 and then introduced into the 2 nd cylinder 13 b. Cooling air is supplied to the intercooler 25 from the blower fan 24 rotated by the rotational driving force from the motor 22.

Fig. 4 is a perspective view showing a two-stage reciprocating compressor 1 according to another embodiment of the present invention. The two-stage reciprocating compressor 1 of fig. 4 is different from the two-stage reciprocating compressor 1 shown in fig. 1 in that a cover 40 is provided. The enclosure 40 is a sound-proof enclosure. The cover 40 may cover the entire circumference of the two-stage reciprocating compressor 1. In the illustrated embodiment, the leg portion 18 in the two-stage reciprocating compressor 1 is exposed with respect to the cover 40 in order to facilitate mounting to the vehicle body. The cover 40 may be provided with a through hole connecting the inside and the outside of the cover 40 at a part thereof. The cover 40 is formed of a material having a sound insulating function. The cover 40 is made of, for example, felt, polyvinyl chloride, or a material having sound insulation properties other than these. The cover 40 can suppress leakage of sound generated from the two-stage reciprocating compressor 1 to the outside.

Fig. 5 is a perspective view showing a two-stage reciprocating compressor 1 according to another embodiment of the present invention. The two-stage reciprocating compressor 1 shown in fig. 5 is different from the two-stage reciprocating compressor 1 shown in fig. 1 in that a muffler 50 is provided. The muffler 50 is attached to the dome 21b of the front side cover 21. The muffler 50 has, for example, a hollow cylindrical shape. The inner space of the muffler 50 is divided into a 1 st chamber into which external air is introduced from the air inlet 50a and a muffling chamber which is connected to the 1 st chamber and into which air is introduced from the 1 st chamber. The intake port 50a can be provided at any position of the muffler 50. The internal space of the muffler 50 may have a space divided in addition to the 1 st chamber and the muffling chamber. The muffling chamber is connected to the intake port 27a of the 1 st cylinder head 17 a. When the motor 22 is driven, the suction chamber of the 1 st cylinder head 17a becomes a negative pressure, and therefore, air is introduced into the 1 st chamber from the outside of the muffler 50. The air enters the anechoic chamber from chamber 1. The air expands in the muffling chamber, and is thus muffled. This reduces intake noise generated when outside air is sucked in.

The two-stage reciprocating compressor 1 can be mounted on a commercial vehicle, for example. One embodiment of the present invention is an automobile including a two-stage reciprocating compressor 1.

The operation and effects of the above-described embodiment will be described below. In one embodiment of the present invention, the blower fan 24 is provided between the rear end surface 11c of the motor housing 11 and the intercooler 25 in the axial direction. This facilitates the cooling air generated by the blower fan 24 to pass through the intercooler 25, thereby improving the cooling effect of the compressed air in the intercooler 25. In a conventional two-stage reciprocating compressor, an intercooler is provided between a rear end surface of a motor housing and a blower fan in an axial direction. In the arrangement of the conventional two-stage reciprocating compressor, the cooling air sent from the blower fan to the intercooler collides with the rear end surface of the motor case and is disturbed in the air flow, and the cooling air from the blower fan does not sufficiently contribute to the cooling of the intercooler. In the embodiment of the present invention, the arrangement in the axial direction of the blower fan and the intercooler is changed, thereby improving the cooling effect.

In the above-described embodiment, the plurality of 1 st ribs 11a extending in the axial direction and the plurality of 2 nd ribs 11b extending in the vertical direction are provided on the outer surface of the motor housing 11. During operation of the two-stage reciprocating compressor 1, joule heat is generated by the applied current applied to the stator coil 22a, and the heat generated in the stator coil 22a is transmitted to the motor housing 11. Since the surface area of the outer surface of the motor case 11 is increased by the 1 st rib 11a and the 2 nd rib 11b, heat generated in the stator coil 22a can be efficiently radiated to the atmosphere.

Further, the 1 st rib 11a guides the cooling air from the air blowing fan 24 in the axial direction along the outer surface of the motor housing 11. Therefore, the cooling air from the blower fan 24 flows between the adjacent 1 st ribs 11a, and therefore, the heat radiation efficiency can be further improved by the cooling air.

The dimensions, materials, and arrangements of the respective components described in the present specification are not limited to the dimensions, materials, and arrangements of the respective components described in the embodiment, and the respective components may be modified and have any dimensions, materials, and arrangements that can be included in the scope of the present invention. Further, components not explicitly described in the present specification may be added to the embodiments described above, and a part of the components described in each embodiment may be omitted.

A part of the modified example is illustrated below. The motor housing 11 and the crankcase 12 may also have an integral, one-piece construction. The motor housing 11 and the crankcase 12 may be formed as separate members. The two-stage reciprocating compressor 1 may also be provided with a control circuit for controlling the motor 22.

Description of the reference numerals

1. A two-stage reciprocating compressor; 10. a housing; 11. a motor housing; 12. a crankcase; 13a, 1 st cylinder (low pressure side cylinder); 13b, 2 nd cylinder (high pressure side cylinder); 14a, the 1 st link; 14b, the 2 nd link; 15. a crankshaft; 15a, 1 st eccentric part; 15b, 2 nd eccentric part; 16a, piston 1; 16b, piston No. 2; 17a, the 1 st cylinder head; 17b, the 2 nd cylinder head; 18. a leg portion; 19. a support portion; 21. a front side cover; 22. a motor; 22a, a stator coil; 22b, a rotor; 22c, a motor rotation shaft; 23. a rear side cover; 24. an air supply fan; 25. an intercooler.

Claims

1. A two-stage reciprocating compressor is provided with:

a rotation drive source housed in the case;

an output shaft that outputs rotation from the rotary drive source and is provided in such a manner that one end thereof protrudes from an end surface of the housing, the output shaft extending in an axial direction;

a low-pressure compression element that compresses air using a rotational driving force from the output shaft as a power source;

an intercooler that cools the compressed air discharged from the low-pressure compression element;

a high-pressure compression element that further compresses the compressed air cooled by the intercooler using a rotational driving force from the motor output shaft as a power source; and

and a blower fan connected to the output shaft and disposed between the end surface of the housing and the intercooler in the axial direction.

2. A two-stage reciprocating compressor in accordance with claim 1,

the housing has a plurality of ribs extending in the axial direction on an outer surface thereof.

3. A two-stage reciprocating compressor in accordance with claim 2,

the housing has a plurality of other ribs extending in a direction perpendicular to the axial direction.

4. A two-stage reciprocating compressor in accordance with any one of claims 1 to 3,

the two-stage reciprocating compressor further includes a muffler for supplying the air to the low-pressure compression element.

5. A two-stage reciprocating compressor in accordance with any one of claims 1 to 4,

the two-stage reciprocating compressor further includes a cover that covers at least a part of the casing, the low-pressure compression element, the intercooler, the high-pressure compression element, and the blower fan in a large number.

6. An automobile provided with the two-stage reciprocating compressor according to any one of claims 1 to 5.