JP2013245592A - Gas compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce suction resistance of a refrigerant to a gas compressor and to prevent liquid compression at the restart of the gas compressor.SOLUTION: A check valve 6 which prevents a refrigerant from flowing backward from a suction chamber 19 to an air conditioning system side is provided in a gas compressor 1. After the gas compressor 1 stops operating, the check valve 6 is closed when a differential pressure between a pressure of the refrigerant in the suction chamber 19 and a pressure of the refrigerant at the air conditioning system side is larger than a predetermined value. In contrast, it is opened when the differential pressure is the predetermined value or less, thereby communicating the suction chamber 19 with the air conditioning system in an operation stop condition of the gas compressor 1.

Description

  The present invention relates to a gas compressor that compresses and supplies a refrigerant to an air conditioner system such as an automobile.

  A gas compressor that supplies refrigerant to an automobile air conditioner system has a refrigerant suction port and discharge port formed in the housing, and compresses refrigerant from the air conditioner system sucked from the suction port and discharges it from the discharge port to the air conditioner system. And a driving force transmission portion that transmits a driving force to the compression mechanism is disposed in the housing. In such a gas compressor, a check valve is arranged to prevent the refrigerant from flowing backward from the suction port to the air conditioner system after the drive is stopped. The check valve is provided in the suction chamber of the suction port, and is formed by a valve seat fixed to the suction chamber and a valve body that can be moved toward and away from the valve seat. The check valve is closed by contact, and the valve body is driven to be open by separating from the valve seat.

  FIG. 7 shows a conventional check valve 100 used in an on-vehicle gas compressor (see Patent Document 1). The check valve 100 is formed by a valve case 110, a valve seat 120, and a valve body 13. Further, a spring 140 is disposed for the check valve 100.

  The valve case 110 is inserted and fixed in a suction chamber 160 communicating with a suction opening 150 of the suction port. The suction opening 150 is connected to the low-pressure side pipe of the air conditioner system, and the suction chamber 160 communicates with the compression mechanism of the gas compressor.

  The valve seat 120 has a cylindrical shape, and is fixed to the valve case 110 so as to be positioned on the suction opening 150 side. The valve body 130 is formed by a cylindrical main body 131 and a seal portion 132 that is provided on the valve seat 120 side of the main body 131 and seals the valve seat 120, and moves in a direction away from the valve seat 120. It is possible. The spring 140 urges the valve body 130 to move toward the valve seat 120. In the figure, an arrow A is a biasing direction by the spring 140, and an arrow B is a refrigerant suction direction.

  In such a check valve 100, the valve body 130 moves to the valve seat 120 side by the biasing of the spring 140 in the direction of arrow A and comes into contact with the valve seat 120, thereby closing the check valve 100. . On the other hand, during operation of the gas compressor, the valve body 130 resists the biasing force of the spring 140 in the direction of arrow A by the pressure of the refrigerant on the air conditioner system side sucked from the suction opening 150 as indicated by arrow B. The check valve 100 is opened. When the operation of the gas compressor is stopped, the pressure of the refrigerant on the suction chamber 160 side (compression mechanism side) is larger than the pressure of the refrigerant on the air conditioner system side (suction opening 150 side). Due to the urging force 140, the valve body 130 moves toward the valve seat 120 and the check valve 100 is closed.

JP 2003-166486 A

  In the conventional gas compressor, since the valve body 130 in the check valve 100 is urged by the spring 140 in the direction of the valve seat 120 (arrow A direction), the spring force of the spring 140 attracts the refrigerant. There is a problem that the suction resistance of the refrigerant sucked from the direction of arrow B increases.

  In a state where the operation of the gas compressor is stopped, that is, in a pressure equalization state where the pressure of the refrigerant on the air conditioner system side and the pressure of the refrigerant on the suction chamber 160 side (compression mechanism side) are equal, the biasing force of the spring 140 Therefore, the check valve 100 is closed. As a result, the refrigerant on the suction chamber 160 side is confined to the compression mechanism side, so that the gasified refrigerant is liquefied. When the gas compressor is restarted in this state, there is a problem that a liquid compression state occurs in which the liquefied refrigerant is compressed.

  Accordingly, an object of the present invention is to provide a gas compressor that can reduce the suction resistance of the refrigerant and can prevent liquid compression at the time of restart.

  According to the first aspect of the present invention, there is provided a housing having a discharge port through which compressed refrigerant is discharged toward the air conditioner system, and a compression mechanism that is provided in the housing and compresses the refrigerant sucked into the housing from the air conditioner system. And a driving force transmission portion for transmitting a driving force to the compression mechanism. The housing has a refrigerant suction chamber, a suction passage communicated with the suction chamber, and the suction passage and the air conditioning system. And the suction passage is opened during operation of the gas compression mechanism, the refrigerant from the air conditioner system is sucked into the suction chamber, and closed when the operation of the gas compression mechanism is stopped. And a check valve for preventing a reverse flow of refrigerant from the suction chamber to the air conditioner system side, the check valve being operated by the gas compressor. After the stop, the gas compressor is closed when the differential pressure between the refrigerant pressure in the suction chamber and the refrigerant pressure on the air conditioner system side is larger than a predetermined value, and is opened when the differential pressure is lower than the predetermined value. When the operation is stopped, the suction chamber and the air conditioning system are in communication with each other.

  The invention according to claim 2 is the gas compressor according to claim 1, wherein the check valve is fully opened when the pressure of the refrigerant on the suction chamber side is equal to the pressure of the refrigerant on the air conditioner system side. It is characterized by becoming a state.

  A third aspect of the present invention is the gas compressor according to the first or second aspect, wherein the check valve includes a valve seat provided on the suction opening side of the suction chamber, and the valve in the suction chamber. A valve body that is provided so as to be freely contactable with respect to the seat and is in contact with the valve seat and is in a closed state, and is opened in a state of being separated from the valve seat, and the operation of the gas compressor is stopped. Immediately after that, there is provided a spring for urging the valve body that is closed by the pressure of the refrigerant on the suction chamber side in a direction away from the valve seat.

  A fourth aspect of the present invention is the gas compressor according to the third aspect, wherein the spring is disposed on the opposite side of the valve seat with the valve body interposed therebetween, and between the valve body and the housing. It is provided.

  A fifth aspect of the present invention is the gas compressor according to the third aspect, wherein the spring is disposed between the valve seat and the valve body and is provided in the valve seat. .

  According to the first aspect of the present invention, the check valve is closed when the differential pressure between the pressure of the refrigerant in the suction chamber and the pressure of the refrigerant on the air conditioner system side is greater than a predetermined value after the operation of the gas compressor is stopped. When the gas compressor is stopped, the refrigerant opens back to the air conditioner system after the gas compressor is shut down. Thus, the refrigerant is not confined on the compression mechanism 3 side, and the refrigerant can be prevented from being liquefied on the compression mechanism 3 side. Therefore, when the gas compressor 1 is restarted, it is possible to prevent the occurrence of a liquid compression state in which the liquefied refrigerant is compressed. Further, the operation of the check valve does not become a resistance when the refrigerant is sucked, and the suction resistance of the refrigerant can be reduced.

  According to the invention of claim 2, since the check valve is fully opened when the pressure of the refrigerant on the suction chamber side and the pressure of the refrigerant on the air conditioner system are equal, after the operation of the gas compressor is stopped, It is possible to prevent the refrigerant from being trapped and liquefied on the compression mechanism side, and to prevent occurrence of a liquid compression state in which the liquefied refrigerant is compressed when the gas compressor 1 is restarted.

  According to the invention described in claim 3, during operation of the gas compressor, the valve body is urged in a direction away from the valve seat, and immediately after the operation of the gas compressor is stopped, the valve is closed by the refrigerant pressure on the suction chamber side. Since the spring is provided to urge the valve body in the direction away from the valve seat, the urging direction of the spring can be the same as the direction in which the refrigerant is sucked into the suction chamber, and the refrigerant is sucked. Therefore, the refrigerant suction resistance can be reduced.

  According to invention of Claim 4 and invention of Claim 5, arrangement | positioning of the spring with respect to a non-return valve can be performed easily.

It is sectional drawing which shows the gas compressor of 1st Embodiment of this invention. It is a check valve used for the gas compressor of a 1st embodiment, and is a sectional view in the operating state of a gas compressor. It is a check valve used for the gas compressor of a 1st embodiment, and is a sectional view in the state just after the operation stop of a gas compressor. It is a non-return valve in 2nd Embodiment of this invention, and is sectional drawing in the operating state of a gas compressor. It is a non-return valve in 2nd Embodiment of this invention, and is sectional drawing in the state immediately after the operation stop of a gas compressor. It is sectional drawing which shows the non-return valve in 3rd Embodiment of this invention. It is sectional drawing of the non-return valve used for the conventional gas compressor.

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

  1 to 3 show a gas compressor according to a first embodiment of the present invention. FIG. 1 is an overall longitudinal sectional view, and FIGS. 2 and 3 are sectional views showing a check valve.

  As shown in FIG. 1, the gas compressor 1 is formed by a housing 2, a compression mechanism 3 and a driving force transmission unit 4 provided inside the housing 2.

  The housing 2 is formed by a front head 2a and a compressor case 2b connected to the front head 2a by bolts, and the whole is hollow. The compression mechanism 3 is disposed and accommodated on the compressor case 2b side, and the driving force transmission unit 4 is disposed and accommodated on the front head 2a side.

  The compression mechanism 3 is a mechanism for compressing refrigerant from an air conditioner system (not shown) sucked into the housing 2. The compression mechanism 3 is attached to a cylinder block 11, a front side block 12 and a rear side block 13 that hold the cylinder block 11 between both sides in the axial direction, and a rotary drive shaft 5 that extends from the drive force transmission unit 4. And the rotor 14.

  The cylinder block 11 is formed with a cylinder chamber 15 in which an elliptical inner wall surface 15 a is formed, and the rotor 14 is rotatably accommodated in the center of the cylinder chamber 15 while being attached to the rotary drive shaft 5. . Here, the rotary drive shaft 5 is rotatably supported by a bearing 16 of the front side block 12 and a bearing 17 of the rear side block 13.

  A plurality of vane grooves (not shown) are formed at equal intervals in the circumferential direction on the outer periphery of the rotor 14, and vanes (not shown) are accommodated in the respective vane grooves so as to be able to appear and retract. The vane advances from the vane groove by the rotation of the rotor and comes into contact with the inner wall surface 15a of the cylinder chamber 15. The cylinder chamber 15 is divided into a plurality of compression chambers by vanes in contact with the inner wall surface 15 a of the cylinder chamber 15. The volume of each compression chamber increases / decreases with the rotation of the rotor 14 and the advance / retreat of the vane, and the refrigerant suction stroke, the compression stroke, and the discharge stroke are repeated according to the volume increase / decrease. In the discharge process, the refrigerant compressed in the compression process is discharged to the air conditioner system.

  In order to suck the refrigerant into the cylinder chamber 15, the front head 2 a is formed with a suction opening 18 connected to a low-pressure side pipe (not shown) of the air conditioner system, and a suction chamber 19 communicating with the suction opening 18. Yes. A suction passage 20 that communicates the suction opening 18 and the suction chamber 19 is formed in the front head 2a, and a check valve 6 described later is disposed in the suction passage 20.

  A discharge port 23 is formed in the compressor case 2b, and the refrigerant compressed in the cylinder chamber 15 is discharged from the discharge port 23 and supplied to the air conditioner system. A high pressure chamber 24 communicating with the discharge port 23 is formed in the compressor case 2 b, an oil reservoir 25 is formed below the high pressure chamber 24, and an oil separator 26 is formed above the high pressure chamber 24. . The oil separator 26 separates and captures oil from the oil-containing refrigerant circulating in the air conditioner system, and the oil reservoir 25 stores the separated oil. The oil stored in the oil reservoir 25 passes through the clearance of the front side block 12, the rear side block 13, the oil hole 11a of the cylinder block 11 and the bearings 16 and 17, and is finally pumped to the back pressure space at the bottom of the vane groove. The

  The driving force transmission unit 4 transmits a rotational driving force from a driving source (not shown) such as an engine to the rotor 14 of the compression mechanism 3.

  The driving force transmission unit 4 includes a pulley 31, a rotor member 32, and an excitation coil 33.

  The pulley 31 is provided outside the front head 2a (housing 2), and rotates by receiving a rotational driving force of the driving source when a V-belt is stretched between the pulley 31 and the driving source. The rotor member 32 is integrally formed on the inner diameter side of the pulley 31 and is rotatably supported by the front head 2a via a bearing 34. The exciting coil 33 is disposed inside the rotor member 32. An armature 35 is disposed outside the rotor member 32, and an outer plate 36 is connected to the armature.

  In such a driving force transmission unit 4, when a voltage is applied to the excitation coil 33, the excitation coil 33 generates a magnetic attraction force and attracts the armature 35 to the rotor member 32. When the armature 35 is sucked by the rotor member 32, the outer plate 36 rotates integrally with the rotor member 32 integrated with the pulley 31, so that the rotational driving force of the drive source is rotated via the outer plate 36. The rotation drive shaft 5 is rotated. Thereby, since the rotor 14 of the compression mechanism 3 rotates, the suction, compression, and discharge of the refrigerant can be performed.

  2 and 3 show the check valve 6. The check valve 6 is disposed inside the suction passage 20 between the refrigerant suction opening 18 and the suction chamber 19, and includes a valve seat 61, a valve body 62 facing the valve seat 61, and these. A valve case (not shown) for housing is formed. In addition to the check valve 6, a spring 7 for biasing the valve body 62 is provided in the valve case. The spring 7 is disposed on the opposite side of the valve seat 61 with the valve body 62 interposed therebetween, and is provided between the valve body 62 and the housing 2 (bubble case).

  The valve seat 61 is formed in a cylindrical shape having both ends opened, and is fixed to the valve case so as to be positioned on the suction opening 18 side. The valve body 62 is formed by a main body portion 62a and a seal portion 62b integrated with the main body portion 62a. The main body 62 a is formed in a cylindrical shape having the same diameter as the valve seat 61. The seal portion 62b is provided so as to close the end portion of the main body portion 62a on the valve seat 61 side. When the valve body 62 comes into contact with the valve seat 61, the cylindrical valve seat 61 and the main body portion of the valve body 62 are provided. The space between 62a can be closed. The valve body 62 is movable in the direction of contact with and away from the valve seat 61.

  When the valve body 62 moves in the direction of the valve seat 61 and contacts the valve seat 61, the check valve 6 is in a closed state, and the refrigerant from the air conditioner system side (suction opening 18 side) to the suction chamber 19 is closed. The passage is blocked, and the valve body 62 moves away from the valve seat 61 to be in an open state, so that the refrigerant can pass therethrough.

  The spring 7 is formed of a coil spring. In this embodiment, the spring 7 is provided on the valve body 62 side by being disposed on the side opposite to the valve seat 61 (lower side) in the valve body 62. The spring 7 biases the valve body 62 so as to move in a direction away from the valve seat 61 (in the direction of arrow C). Such a biasing direction of the spring 7 is the same as the direction in which the refrigerant is sucked into the suction chamber 19 (direction B), and therefore does not become a resistance when the refrigerant is sucked, and the suction resistance of the refrigerant is reduced. Can be reduced.

  During the operation of the gas compressor 1, the above check valve 6 is in an open state in which the valve body 62 is separated from the valve seat 61 due to the biasing force of the spring 7 and the pressure of the refrigerant, and the check valve 6 from the air conditioner system side (suction opening 18 side). The refrigerant is sucked into the suction chamber 19 (compression mechanism 3). FIG. 2 shows an open state of the check valve 6 during operation of the gas compressor 1.

  On the other hand, when the operation of the gas compressor 1 is stopped, the valve body 62 is in a closed state in contact with the valve seat 61. This prevents the refrigerant in the suction chamber 19 (compression mechanism 3) from flowing back to the air conditioner system side (suction opening 18 side). FIG. 3 shows the closed state of the check valve 6 when the operation of the gas compressor 1 is stopped, and the refrigerant can be prevented from flowing back in the direction indicated by the arrow D.

  When the operation of the gas compressor 1 is stopped, the check valve 6 is operated after the operation of the gas compressor 1 is stopped, the refrigerant pressure Pth (see FIG. 1) in the suction chamber 19 (compression mechanism 3) and the air conditioner system side (see FIG. 1). When the differential pressure from the refrigerant pressure Ps (see FIG. 1) on the suction opening 18 side is larger than a predetermined value α (Pth−Ps> α), the spring 7 is closed against the biasing force, and the difference When the pressure is smaller than a predetermined value (Pth−Ps <α), the biasing force of the spring 7 is also applied to open the gas compressor 1, and the suction chamber 19 and the air conditioner system are in communication with each other when the operation of the gas compressor 1 is stopped. It is set to become. Such a setting can be performed by adjusting the spring force of the spring 7 based on the correlation with the refrigerant pressure.

  By setting in this way, the refrigerant is not confined to the compression mechanism 3 side after the operation of the gas compressor 1 is stopped, and the refrigerant can be prevented from being liquefied on the compression mechanism 3 side. As a result, when the gas compressor 1 is restarted, it is possible to prevent the occurrence of a liquid compression state in which the liquefied refrigerant is compressed.

  In addition to the above, after the operation of the gas compressor 1 is stopped, the pressure is equal (Pth) equal to the refrigerant pressure on the suction chamber 19 side (compression mechanism 3 side) and the refrigerant pressure on the air conditioner system side (suction opening 18 side). = Ps) is set so that the valve element 62 is at a maximum distance from the valve seat 61, that is, fully opened. By setting in this way, the refrigerant can efficiently flow out from the suction chamber 19 side toward the air conditioner system side. For this reason, after the operation of the gas compressor 1 is stopped, it is possible to more reliably prevent the refrigerant from being trapped on the compression mechanism 3 side, and to prevent the refrigerant from being liquefied on the compression mechanism 3 side. As a result, when the gas compressor 1 is restarted, it is possible to prevent the occurrence of a liquid compression state in which the liquefied refrigerant is compressed.

  4 and 5 show the check valve 6 according to the second embodiment of the present invention. FIG. 4 shows the operating state of the gas compressor 1 and FIG. 5 shows the operating state of the gas compressor 1.

  In the check valve 6 of this embodiment, a spring 7 made of a coil spring is provided on the valve seat 61 side of the check valve 6, and a lower end portion presses the valve body 62. That is, the spring 7 is disposed between the valve seat 61 and the valve body 62 and is provided on the valve seat 61. As a result, the spring 7 biases the valve body 62 in a direction away from the valve seat 61 (C direction).

  Also in this embodiment, the urging direction of the spring 7 is the same as the direction in which the refrigerant is sucked into the suction chamber 19 (the B direction), so that there is no resistance when the refrigerant is sucked, and the refrigerant Inhalation resistance can be reduced.

  The check valve 6 is activated when the differential pressure between the refrigerant pressure Pth in the suction chamber 19 and the refrigerant pressure Ps on the air conditioner system side is greater than a predetermined value α after the operation of the gas compressor 1 is stopped ( Pth−Ps> α), when the differential pressure is smaller than a predetermined value (Pth−Ps <α) when the spring 7 is closed against the biasing force of the spring 7, and the biasing force of the spring 7 is also applied to open the pressure. When the operation of the gas compressor 1 is stopped, the suction chamber 19 and the air conditioner system are set in a communication state. By setting in this way, the refrigerant is not confined to the compression mechanism 3 side after the operation of the gas compressor 1 is stopped, and the refrigerant can be prevented from being liquefied on the compression mechanism 3 side. For this reason, at the time of restart of the gas compressor 1, generation | occurrence | production of the liquid compression state which compresses the liquefied refrigerant | coolant can be prevented.

  Further, after the operation of the gas compressor 1 is stopped, the pressure is equal to the refrigerant pressure on the suction chamber 19 side (compression mechanism 3 side) and the refrigerant pressure on the air conditioner system side (suction opening 18 side) (Pth = Ps). Is set so that the valve body 62 is at a maximum distance from the valve seat 61, that is, in a fully open state. Thereby, after the operation of the gas compressor 1 is stopped, it is possible to more reliably prevent the refrigerant from being confined on the compression mechanism 3 side, to prevent the refrigerant from being liquefied on the compression mechanism 3 side. Occurrence of a liquid compression state at the time of restart can be prevented.

  FIG. 6 shows a check valve 6 in the third embodiment of the present invention. In this embodiment, a spring 7 made of a coil spring is disposed on the valve body 62 side of the check valve 6, that is, on the opposite side of the valve seat 61 with the valve body 62 interposed therebetween, and is provided on the valve body 62.

This spring 7 elastically holds the valve body 62 so that the seal portion 62b of the valve body 62 is positioned on the lower side away from the valve seat 61 in a free state, that is, the check valve is opened. When the valve body 62 moves toward the valve seat 61 due to the pressure of the refrigerant in the suction chamber 19, the valve body 62 is urged away from the valve seat 61.

  The check valve 6 is activated when the differential pressure between the refrigerant pressure Pth in the suction chamber 19 and the refrigerant pressure Ps on the air conditioner system side is greater than a predetermined value α after the operation of the gas compressor 1 is stopped ( Pth−Ps> α), when the differential pressure is smaller than a predetermined value (Pth−Ps <α), the spring 7 is biased to open and the gas is opened. In the operation stop state of the compressor 1, the suction chamber 19 and the air conditioner system are set to be in a communication state (state shown in FIG. 6). By setting in this way, the refrigerant is not confined on the compression mechanism 3 side, and the refrigerant can be prevented from being liquefied on the compression mechanism 3 side. For this reason, at the time of restart of the gas compressor 1, generation | occurrence | production of the liquid compression state which compresses the liquefied refrigerant | coolant can be prevented.

  Also in the present embodiment, immediately after the operation of the gas compressor 1 is stopped, the refrigerant can be reliably prevented from being confined on the compression mechanism 3 side, and the refrigerant can be prevented from being liquefied on the compression mechanism 3 side. It is possible to prevent the occurrence of a liquid compression state at the time of restarting 1.

  In the above embodiment, a coil spring is used as the spring 7 that biases the valve body 62 of the check valve 6, but a plurality of stacked disc springs or leaf springs may be used instead.

DESCRIPTION OF SYMBOLS 1 Gas compressor 2 Housing 2a Front head 3 Compression mechanism 4 Driving force transmission part 6 Check valve
7 Spring
18 Suction opening 19 Suction chamber
20 Suction passage 23 Discharge port 61 Valve seat 62 Valve body

Claims (5)

A housing having a discharge port through which compressed refrigerant is discharged toward the air conditioner system, a compression mechanism that is provided in the housing and compresses the refrigerant sucked into the housing from the air conditioner system, and a driving force applied to the compression mechanism And a driving force transmission part for transmitting
The housing is provided with a refrigerant suction chamber, a suction passage communicating with the suction chamber, and a suction opening communicating the suction passage with the air conditioning system.
The suction passage is opened during operation of the gas compression mechanism, and the refrigerant from the air conditioner system is sucked into the suction chamber, and closed when the operation of the gas compression mechanism is stopped, the refrigerant from the suction chamber is discharged. A gas compressor provided with a check valve that prevents backflow to the air conditioner system,
The check valve is closed when the differential pressure between the refrigerant pressure in the suction chamber and the refrigerant pressure on the air conditioner system side is larger than a predetermined value after the gas compressor is stopped, and the differential pressure is predetermined. When the gas compressor is below the value, the gas compressor is opened, and the gas compressor is in a communication state between the suction chamber and the air conditioner system when the gas compressor is stopped. The gas compressor according to claim 1,
The check valve is fully opened when the pressure of the refrigerant on the suction chamber side is equal to the pressure of the refrigerant on the air conditioner system side. The gas compressor according to claim 1 or 2,
The check valve is in a closed state in a state in which the check valve is provided on the suction opening side of the suction chamber and in contact with the valve seat in the suction chamber so as to be able to contact with and separate from the valve seat. And is formed with a valve body that is opened in a state of being separated from the valve seat,
Immediately after the operation of the gas compressor is stopped, the gas compressor is provided with a spring that urges the valve body that is closed by the pressure of the refrigerant on the suction chamber side in a direction away from the valve seat. A gas compressor according to claim 3, wherein
The gas compressor according to claim 1, wherein the spring is disposed on the opposite side of the valve seat with the valve body interposed therebetween, and is provided between the valve body and the housing. A gas compressor according to claim 3, wherein
The gas compressor is provided between the valve seat and the valve body, and is provided in the valve seat.

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