JP2006077731A - Reciprocating compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reciprocating compressor, capable of reducing manufacture cost of a compressor. <P>SOLUTION: In this compressor, refrigerant taken in from a refrigeration circuit is compressed, delivery capacity is varied by adjustment of pressure in a crank chamber, and compressed refrigerant gas is delivered to a delivery chamber to be sent to the refrigeration circuit. It is provided with a housing 16, a delivery passage 76 formed in the housing to communicate the delivery chamber 64 with the refrigeration circuit to which the compressed refrigerant gas is sent, having a female screw part 76b on the inner circumferential side, and a check valve 80 provided with a vale main body 82 having a male screw part 82a to be engaged with the female screw part on the outer circumferential side. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a reciprocating compressor, and more particularly to a reciprocating compressor suitable for being incorporated in a refrigeration circuit of an air conditioning system of a vehicle.

  This type of compressor is incorporated in a refrigeration circuit, and is disposed in an engine room in an automobile, for example. More specifically, this compressor is connected to an evaporator disposed in an instrument panel that partitions between an engine room and a vehicle compartment via a return path of the refrigerant circulation path, A condenser and an expansion valve are inserted. The compressor sucks the refrigerant from the return path of the circulation path into the suction chamber and compresses it in the compression chamber, and the compressed refrigerant gas is sent out toward the condenser via the discharge chamber.

The discharge chamber and the condenser are connected by a discharge passage, and a check valve may be provided in the discharge passage. This is to prevent the refrigerant gas traveling toward the condenser from flowing back into the discharge chamber. Further, when the compressor is a clutchless type, that is, a compressor that is driven as the engine is driven, the check valve can achieve a substantially 0% discharge capacity by closing the valve. (Patent Document 1).
JP 2000-346217 A

By the way, in the said prior art, the structure of the check valve press-fitted and fixed to the discharge passage and the structure of the check valve fixed to the discharge passage using a snap ring are described.
Here, considering that the check valve is generally manufactured as a separate part from the discharge passage or the like, the need for a snap ring is disadvantageous in terms of the number of parts.
On the other hand, if the check valve is press-fitted and fixed in the discharge passage, the shape near the discharge passage will be deformed, and it will be difficult to remove the check valve once it has been installed in the compressor. There is concern that it will lead to replacement of the housing itself. Furthermore, press-fit fitting accuracy, in other words, high-precision dimensional control for press-fitting is also required.

As described above, in the conventional technique, no special consideration is given to the reduction of the manufacturing cost of the compressor.
This invention is made | formed in view of such a subject, and it aims at providing the reciprocating type compressor which can aim at reduction of the manufacturing cost of a compressor.

  In order to achieve the above object, the reciprocating compressor according to claim 1 compresses the refrigerant sucked from the refrigeration circuit, changes the discharge capacity by adjusting the pressure of the crank chamber, and discharges the compressed refrigerant gas to the discharge chamber. And a compressor that delivers the refrigerant to the refrigeration circuit, wherein the housing is connected to the refrigeration circuit that is formed in the housing and delivers the compressed refrigerant gas, and has a female thread portion on the inner peripheral side thereof. And a check valve provided with a valve body having a male screw portion screwed into the female screw portion on the outer peripheral side thereof.

In the invention according to claim 2, the valve body has a valve hole connected to the discharge chamber and opened and closed by the valve body, and the valve hole is formed on the valve body side with one opening facing the discharge chamber side. Another opening is opposed, and a tool groove is allowed on the periphery of one opening to allow insertion of a tool toward the valve hole, and the diameter thereof is larger than the other opening diameter.
Furthermore, the invention described in claim 3 is characterized in that the tool groove has a negative shape, a positive shape, a hexagonal shape, or a Torx shape.

Therefore, according to the reciprocating compressor of the first aspect of the present invention, since the outer peripheral side of the valve body and the inner peripheral side of the discharge passage are fixed with screws, a snap ring is unnecessary compared to the conventional case. Thus, the number of parts is reduced.
Further, since the valve body is screwed into the discharge passage, processing for press-fitting the valve body is not necessary as compared with the conventional case. That is, high-precision dimension management for press-fitting is not necessary.

As a result, the manufacturing cost of the compressor can be reduced.
According to the second aspect of the present invention, when the check valve is detached from the housing, the tool may be inserted into the tool groove and the valve body may be rotated together with the tool. Is easy to remove.
Moreover, since the tool groove diameter is larger than the other opening diameter of the valve hole, the tool groove diameter can be sent to the refrigeration circuit without hindering the flow rate of the compressed refrigerant gas from the discharge chamber toward the valve body.

  Furthermore, according to the third aspect of the invention, the check valve can be automatically attached and detached by the shape of the tool groove as described above. As a result, the manufacturing cost can be further reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a swash plate compressor according to an embodiment of a reciprocating compressor. The compressor 2 is incorporated in a refrigeration circuit of a vehicle air conditioning system. Specifically, a compressor 2, a condenser 6, an expansion valve 8 and an evaporator 10 are sequentially arranged in the refrigerant circulation path 4 of this refrigeration circuit, and the compressor 2 sucks refrigerant from the return path of the refrigerant circulation path 4. The refrigerant is compressed and discharged toward the forward path of the refrigerant circulation path 4.

The compressor 2 includes a cylinder block 12. A front housing 14 is connected to one end side of the cylinder block 12, and a cylinder head (housing) 16 is connected to the other end side by connecting bolts. FIG. 1 shows only the connecting bolt that connects the front housing 14 and the cylinder head 16.
A drive shaft 20 is disposed in the center of the front housing 14, and one end side of the drive shaft 20 passes through the front housing 14 and is rotatably supported by the front housing 14 via a bearing 22. On the other hand, the other end of the drive shaft 20 enters a center hole 24 formed through the center of the cylinder block 12 and is rotatably supported by the cylinder block 12 via a bearing 26.

A drive pulley 28 is attached to one end of the drive shaft 20 via a bolt 30. The drive pulley 28 is rotatably supported by the front housing 14 via a bearing 32, and is rotated by receiving power from a vehicle engine (not shown). Accordingly, the rotation of the drive pulley 28 is transmitted to the drive shaft 20 as the engine is driven, and the drive shaft 20 is rotated in one direction.
For example, seven cylinder bores 34 are formed in the cylinder block 12. These cylinder bores 34 are arranged at equal intervals in the circumferential direction of the cylinder block 12, and penetrate the cylinder block 12 in the axial direction in parallel with the drive shaft 20.

Pistons 36 are slidably fitted into the cylinder bores 34, and one end of each piston 36 is formed as a tail 38 projecting from the cylinder block 12 into the front housing 14, that is, into the crank chamber 18. The tail 38 has a pair of shoes 40, and the outer peripheral edge portion of the swash plate 42 is slidably sandwiched between the shoes 40.
The swash plate 42 is attached to the drive shaft 20, and a rotor 44 positioned between the front housing 14 and the swash plate 42 is attached to the drive shaft 20. The swash plate 42 and the rotor 44 rotate integrally with the drive shaft 20, and the swash plate 42 is connected to the rotor 44 via a hinge 46 so as to be tiltable according to contact with the ring 48. Further, a coil spring 50 is attached to the drive shaft 20 so as to surround the drive shaft 20, and the coil spring 50 presses the swash plate 42 toward the cylinder head 16 according to the reciprocating linear motion of the piston 36. Energized.

  On the other hand, a circular valve plate 56 is sandwiched between the cylinder block 12 and the cylinder head 16 via gaskets 52 and 54. The valve plate 56 is disposed in each cylinder bore 34 and the other end of the piston 36. A compression chamber 58 is formed with the gasket 52. A discharge port 60 and a suction port 61 are formed in the valve plate 56 for each cylinder bore 34. The communication passage 62 is formed at the center of the valve plate 56. That is, when viewed in the radial direction of the valve plate 56, the suction port 61 is positioned outside the communication path 62, and the discharge port 60 is positioned outside the suction port 61.

  The cylinder head 16 has a cup shape opened toward the cylinder block 12, and the open end of the cup shape is airtightly fitted to the valve plate 56 via the gasket 54 and connected to the cylinder block 12. The cylinder head 16 has an annular discharge chamber 64 and a suction chamber 66 which are independent from each other. The suction chamber 66 is disposed at the center of the cylinder head 16, and the discharge chamber 64 is disposed on the outer peripheral side thereof.

The suction chamber 66 communicates with the compression chamber 58 of each cylinder bore 34 via the suction port 61. The suction chamber 66 is always in communication with the crank chamber 18 via the central hole 24 and the communication passage 62 provided in the cylinder block 12. The communication passage 62 has a throttle in the middle thereof, and can gradually release the pressure in the crank chamber 18 to the suction chamber 66 side.
On the other hand, the discharge chamber 64 communicates with the compression chamber 58 of each cylinder bore 34 via the discharge port 60, and this discharge port 60 is opened and closed from the discharge chamber 64 side by the discharge reed valve 68. The discharge chamber 64 also communicates with the crank chamber 18, and an electromagnetic control valve 70 is inserted in the middle of the communication.

  The electromagnetic control valve 70 is actuated by an output signal from the air conditioner ECU 72. The air conditioner ECU 72 includes an input / output device, a memory (ROM, RAM, non-volatile RAM, etc.), a CPU, and the like. The air conditioner ECU 72 performs comprehensive control including capacity control of the compressor 2. . The refrigerant in the discharge chamber 64 is supplied to the crank chamber 18 via the connection paths 73 and 74 in accordance with the opening / closing operation by the electromagnetic control valve 70.

Further, a discharge passage 76 and a suction passage 78 communicating with the discharge chamber 64 and the suction chamber 66, respectively, are formed on the peripheral wall of the cylinder head 16, and the suction passage 78 is connected to the return path of the circulation path 4. It is connected to the forward path of the circulation path 4. A check valve 80 is disposed in the discharge passage 76.
Details of the check valve 80 are shown in FIG.

  As shown in FIG. 5A, the discharge passage 76 of the cylinder head 16 includes a bottomed tubular storage chamber 76a connected to the discharge chamber 64, and the discharge chamber 64 and the inner peripheral side of the storage chamber 76a. A female screw portion 76b having a predetermined length is formed from the boundary position toward the axial direction of the drive shaft 20. The storage chamber 76 a is connected to the connection passage 76 c and communicates the discharge chamber 64 with the forward path of the circulation path 4.

  The check valve 80 is mounted in the storage chamber 76a, and prevents the refrigerant gas sent to the forward path of the circulation path 4 from flowing back into the discharge chamber 64. More specifically, the check valve 80 includes a cylindrical valve main body 82, and a male screw portion 82 a that is screwed into the female screw portion 76 b is formed on the outer peripheral side of the valve main body 82. Further, a stepped valve hole 84 having a small diameter toward the valve body 90 is formed on the inner peripheral side of the valve body 82.

  Specifically, the valve hole 84 is connected to the discharge chamber 64 via the discharge chamber counter opening 84c. The valve hole 84 has a discharge chamber facing port (one opening) 84c facing the discharge chamber 64 side, and a valve body facing port (other opening) 84b facing the valve body 90 side. A Torx groove (tool groove) 84a is formed at the periphery of the discharge chamber counter opening 84c (FIG. 5B). The torque groove 84a is formed to have a diameter larger than the opening diameter of the valve body-facing port 84b, and allows insertion of a tool (not shown) when the check valve 80 is attached to or detached from the cylinder head 16.

Further, the valve hole 84 is opened and closed by the valve body 90. The valve body 90 is accommodated in a cup-shaped case 88 that opens toward the discharge chamber 64, and an opening 88 d of the case 88 is engaged with a protrusion 82 b of the valve body 82, and the bottom of the case 88 is A stopper 88 a that is convex toward the discharge chamber 64 is formed in the portion.
In the case 88, a spring 91 is provided between the back side of the valve body 90 and the bottom portion of the case 88, and the valve body 90 moves toward the discharge chamber 64 by the biasing force of the spring 91. Further, a communication hole 88b communicating with the storage chamber 76a is formed in the central portion of the stopper 88a, and the compressed refrigerant gas is introduced into the case 88. That is, the biasing force of the spring 91 is assisted by the configuration of the convex stopper 88a and the communication hole 88b, and the spring 91 is prevented from buckling.

  As described above, the check valve 80 is configured by joining the case 88 in which the spring 91 and the valve body 90 are stored to the valve main body 82, and is inserted into the storage chamber 76 a through the O-ring 86. Next, the tool is inserted into the Torx groove 84a and rotated so that the male screw portion 82a of the valve body 82 and the female screw portion 76b of the storage chamber 76a are screwed together. As a result, the check valve 80 is fixed to the discharge passage 76. Thereafter, the discharge chamber counter inlet 84c is caulked with a punch or the like, and the rotation of the check valve 80 relative to the discharge passage 76 is prevented.

  When the heat load of the refrigeration cycle increases and the electromagnetic control valve 70 is excited by the output signal from the air conditioner ECU 72, the pressure in the discharge chamber 64 is not supplied to the crank chamber 18. On the other hand, since the pressure in the crank chamber 18 is gradually released to the suction chamber 66 through the throttle in the communication passage 62, the pressure gradually decreases and the back pressure applied to the piston 36 also decreases. Thereby, the inclination | tilt angle of the swash plate 42 becomes large. When the compressor 2 is required to operate at the maximum capacity, the swash plate 42 rotates with the maximum inclination angle.

  The rotation of the swash plate 42 is converted into a reciprocating linear motion of each piston 36. Here, when the piston 36 moves in a direction to increase the compression chamber 58 in the cylinder bore 34, the refrigerant gas is sucked from the suction chamber 66 through the suction port 61. Thereafter, when the piston 36 moves toward the discharge chamber 64, the refrigerant sucked into the compression chamber 58 is compressed, and when the compression pressure exceeds the cutoff pressure of the discharge reed valve 68, the discharge reed valve 68 is turned on. be opened. As a result, the compressed refrigerant is discharged from the compression chamber 58 into the discharge chamber 64 through the discharge port 60.

  The discharged refrigerant enters the valve hole 84 of the check valve 80. When the pressure of the refrigerant exceeds the urging force of the spring 91, the valve body 90 is opened against the urging force of the spring 91. Along with the opening of the valve hole 84 by the valve body 90, the refrigerant discharged from the discharge chamber 64 is the valve hole 84, a plurality of valve openings 88c provided on the outer periphery of the case 88 shown in FIG. It is sent out toward the refrigerant circulation path 4 through a connection passage 76c extending in a substantially vertical direction facing the valve port 88c.

Thereafter, the delivered refrigerant is condensed in the condenser 6, and the refrigerant in a gas-liquid mixed state is supplied to the evaporator 10 through the expansion valve 8. The two-phase refrigerant is vaporized in the evaporator 10, and the air around the evaporator 10 is cooled by the heat of vaporization. Accordingly, the cooling air can be cooled by introducing such cooling air into the vehicle interior.
As described above, according to the compressor 2 of the present embodiment, the outer peripheral side of the valve body 82 and the inner peripheral side of the discharge passage 76 are fixed with screws. Therefore, a snap ring for fixing the check valve to the discharge passage is not required as compared with the conventional configuration, and the number of parts is reduced. Further, the valve body 82 is screwed into the discharge passage 76. Therefore, it is not necessary to press-fit the valve body as compared with the conventional configuration. That is, highly accurate dimensional management for press-fitting becomes unnecessary. As a result, the manufacturing cost of the compressor 2 can be reduced.

Further, if the fixing portion by the snap ring is not necessary, the total length of the storage portion 76a required for storing the check valve 80 is shortened, and consequently the compressor 2 can be downsized.
Further, when the check valve 80 is attached to and detached from the cylinder head 16, a tool may be inserted into the Torx groove 84 a and the valve body 82 may be rotated together with the tool, and the check valve 80 is attached to and detached from the cylinder head 16. Becomes easier.

Furthermore, since the diameter of the torque groove 84a is larger than that of the valve body-facing port 84b, the torque can be sent to the refrigerant circulation path 4 without hindering the flow rate of the refrigerant from the discharge chamber 64 toward the valve body 90. In addition, the configuration of the torx groove 84a makes it possible to automate the removal and attachment of the check valve 80. As a result, the manufacturing cost of the compressor 2 can be further reduced.
The description of one embodiment of the present invention is finished above, but the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

For example, in the above embodiment, the Torx groove 84a is formed in the valve body 82, but the present invention is not necessarily limited to this form.
As an example, as shown in FIG. 3, a male threaded portion 92a is formed on the outer peripheral side of the valve body 92, and a minus groove 94a having a diameter larger than the diameter of the valve body-facing port 94b is formed in the central portion of the valve body 92. May be formed as a tool groove ((a) in the figure). In this case, the outer diameter of the minus groove 94a is larger than the diameter of the valve body-facing port 94b (FIG. 5B).

  Further, as shown in FIG. 4, a plus (cross) groove 104a having a diameter larger than the diameter of the valve element counter opening 104b is formed as a tool groove in the central portion of the valve main body 102 screwed through the male screw portion 102a. Alternatively, a hexagonal groove 114a having a diameter larger than the diameter of the valve body-facing port 114b may be formed as a tool groove in the valve main body 112 to be formed (FIG. 5A) or screwed through the male screw portion 112a. Good ((b) in the figure).

Also in these cases, similarly to the above, the flow rate of the refrigerant from the discharge chamber to the valve body is not hindered, and it is possible to automate the desorption of the check valve.
The above-described Torx groove 84a, minus groove 94a, plus groove 104a, and hexagonal groove 114a are provided from the discharge chamber inlet to the valve element inlet so long as the refrigerant flow from the discharge chamber to the valve body and the insertion of the tool are not hindered. It may be formed in a taper shape that is reduced in diameter.

  Further, the present invention can be applied to a swing plate type reciprocating compressor in addition to the swash plate type compressor.

1 is a longitudinal sectional view showing a reciprocating compressor according to an embodiment of the present invention. It is an expanded sectional view of the check valve of FIG. It is explanatory drawing of the non-return valve in another Example. It is explanatory drawing of the non-return valve in another Example.

Explanation of symbols

2 Swash plate compressor (reciprocating compressor)
16 Cylinder head (housing)
18 Crank chamber 64 Discharge chamber 76 Discharge passage 76b Female thread portion 80 Check valve 82, 92, 102, 112 Valve body 82a, 92a, 102a, 112a Male thread portion 84 Valve hole 84a Torx groove (tool groove)
84b, 94b, 104b, 114b Valve body opposite mouth (other opening)
84c Discharge chamber opposite entrance (one opening)
90 Disc 94a Minus groove (tool groove)
104a Plus groove (tool groove)
114a Hexagonal groove (tool groove)

Claims (3)

A compressor that compresses refrigerant sucked from a refrigeration circuit, changes a discharge capacity by adjusting a pressure in a crank chamber, discharges compressed refrigerant gas to a discharge chamber, and sends the compressed refrigerant gas to the refrigeration circuit,
A housing;
A discharge passage formed in the housing, communicating the discharge chamber and the refrigeration circuit for sending out the compressed refrigerant gas, and having a female screw portion on an inner peripheral side thereof;
A reciprocating compressor comprising a check valve provided with a valve body having a male thread portion screwed into the female thread portion on an outer peripheral side thereof. The valve body is connected to the discharge chamber and has a valve hole that is opened and closed by a valve body,
The valve hole has one opening facing the discharge chamber side and another opening facing the valve body side,
The reciprocating motion according to claim 1, wherein a tool groove is allowed at a peripheral edge of the one opening toward the valve hole, and a diameter of the tool groove is larger than that of the other opening diameter. Mold compressor.   The reciprocating compressor according to claim 2, wherein the tool groove has a negative shape, a positive shape, a hexagonal shape, or a Torx shape.

Images