JP2000346220A - Check valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a check valve in which a valve seat member and a housing that are assembled hardly come off in service, thus resolving drawbacks of a compressor, a cooling circuit and a vehicle. SOLUTION: This check valve is composed of a valve seat member 70, a housing 71, a valve element 72 and a spring 73. In this case, a recess 70c of the valve seat member 70 and each projection 71a of the case 71 are prevented by each flange 71g of the case 71 from slipping off. Each flange 71g is fan- shaped, pairing off with the other and is positioned only in the outer part of the projection 71a, abutting against the inner wall of a storage chamber. The thickness of each flange 71g includes the thickness of the projection 71a, and the outer face of the flange 71g is flush with the outer peripheral face of a main body part 70a of the valve seat member 70.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a check valve. This check valve is suitable for use in a cooling circuit equipped with a variable displacement compressor or the compressor itself, particularly when the compressor is operatively connected to an external drive source in a clutchless manner. It is suitable for use when the discharge capacity of 0% can be realized.

[0002]

2. Description of the Related Art For example, a compressor for compressing refrigerant gas is incorporated in a cooling circuit used in a vehicle air conditioning system. Such a compressor is normally operatively connected to an engine of a vehicle as an external drive source via an electromagnetic clutch, and is connected to the engine by the electromagnetic clutch only when a cooling load occurs to perform a compression operation. ing. However, if an electromagnetic clutch is provided in addition to the compressor in this way, there are disadvantages in that an increase in overall weight, an increase in manufacturing cost, and an unavoidable power consumption for operating the electromagnetic clutch are required. For this reason, in recent years, there has been proposed a so-called clutchless type variable displacement swash plate type compressor which is directly connected to an external drive source without interposing an electromagnetic clutch, and is always driven while the external drive source is being driven (Japanese Patent Laid-Open No. Hei 10 (1999)).
-205446).

In the compressor described in the publication, a swash plate that can be tilted with respect to a drive shaft directly connected to an external drive source maintains its minimum tilt angle so as to provide a discharge capacity other than 0%. I have. Therefore, in this compressor, the power consumption of the external drive source can be extremely reduced while realizing weight reduction and the like by operating and connecting without using the electromagnetic clutch.

In this compressor, as shown in FIG. 12, a discharge chamber 91 and a storage chamber 9 adjacent to the discharge chamber 91 are arranged.
2 and a discharge passage 93 for connecting the storage chamber 92 to a condenser (not shown) of the cooling circuit are formed in the housing 90, and the check valve 9 for preventing the backflow of the refrigerant gas into the storage chamber 92.
4 is provided with an O-ring 95 and a circlip 96. More specifically, the check valve 94 is configured as shown in FIG.
As shown in FIGS. 3 and 14, a valve seat member 81, a case 82 fitted to the valve seat member 81, a valve element 83 slidably provided in the case 82 in the axial direction, and a case 82. And a spring 84 for urging the valve element 83 in the direction of the valve seat member 81.

[0005] The valve seat member 81 has a passage 81a communicating therewith with the discharge chamber 91, and a seat surface 81b is formed around a passage opening of the passage 81a opened inside the case 82. An annular recess 81 is provided on the outer peripheral surface around the seating surface 81b.
c is recessed. On the inner surface of the open end of the case 82, a convex portion 82a fitted from the outer peripheral side to the concave portion 81c is formed,
A communication port 82b is opened on the peripheral wall on the axial side of the seat surface 81b.

[0006] The valve body 83 slides in one direction to slide the seat surface 81b.
And a seal surface 83a that slides in the other direction and slides away from the seat surface 81b, and an outer peripheral surface 83b orthogonal to the seal surface 83a. In this check valve 94, as shown in FIG. 13, if the external drive source is stopped and the compressor is stopped, the high-pressure refrigerant gas on the condenser side communicates with the communication port 82b.
, The valve body 83 is pressed in one direction, and the spring force of the spring 84 is also helped to slide the valve body 83 in one direction. Therefore, the seal surface 83a is seated on the seat surface 81b of the valve seat member 81, and the communication between the flow path 81a and the communication port 82b is stopped. For this reason,
The high-pressure refrigerant gas on the condenser side does not flow back into the discharge chamber 91.

On the other hand, as shown in FIG. 14, during operation of the compressor, the high-pressure refrigerant gas in the discharge chamber 91 presses the valve element 83 from the flow path 81b in the other direction, and overcomes the urging force of the spring 84. The valve body 83 is slid in the other direction. Therefore, the seal surface 83a is separated from the seat surface 81b of the valve seat member 81, and the flow path 81a and the communication port 82b communicate with each other. For this reason, the high-pressure refrigerant gas in the discharge chamber 91 is discharged to the condenser.

As described above, in the compressor provided with the check valve 94, the backflow of the refrigerant gas during stoppage can be prevented, so that the storage of the liquid refrigerant in the compressor can be prevented, and the excessive flow in the compressor can be prevented. Pressure rise and temperature rise can be prevented, and the durability of the compressor can be increased. Also, the discharge chamber 91
In the compressor in which the flow passage is formed in the crank chamber (not shown), since the pressure increase in the crank chamber during stoppage can be suppressed, the inclination angle of the swash plate increases at the time of starting, the capacity return becomes quick, and thus the speed is increased. A cooling effect can be exerted.

[0009]

However, according to the test results of the inventors, in the check valve 94, the convex portion 82a of the case 82 is simply fitted into the concave portion 81c of the valve seat member 81 from the outer peripheral side. As a result, since the case 82 is assembled to the valve seat member 81, a large amount of fluid such as high-pressure refrigerant gas
When trying to flow into 1a, the valve element 83 that is fully open pushes the case 82 strongly in the other direction, and the fitting between the concave portion 81c and the convex portion 82a may be detached. In this case, the valve seat member 81 and the case 82 are disassembled from each other, and can no longer function as the check valve 94.

In this respect, the bottom surface of the storage chamber 92 is brought into contact with the top surface of the case 82 to prevent the case 82 from moving in the direction in which the case 82 comes off. Although it is conceivable to make it impossible to move in the disengaging direction, in such a case, the storage chamber 92 and the check valve 94 must be manufactured with high dimensional accuracy, thereby increasing the manufacturing cost. There is a risk.

In particular, when the check valve 94 is provided on the condenser side of the compressor in the cooling circuit or on the downstream side of the discharge chamber 91 of the compressor, the pressure in the flow passage 81a is high, so that the valve seat member 81 and the case 82 are easily detached,
This is a serious problem for a cooling circuit and thus for a vehicle equipped with the cooling circuit. Further, a compressor operatively connected to an external drive source in a clutchless manner is preferably equipped with such a check valve 94 because of the above-mentioned effects, but if the function of the check valve 94 is impaired during use, The effect is also reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and provides a check valve in which a valve seat member and a case are hardly disassembled during use, and thus a compressor, a cooling circuit, and a vehicle. The task is to resolve the shortcomings.

[0013]

A check valve according to the present invention comprises a flow path having a flow path port, a seat surface formed around the flow path port, and an adherend formed around the seat surface. Having a valve seat member, a fitting portion fitted to the attached portion from the outer peripheral side, and a communication port opened to a peripheral surface on an axial side from the seat surface, and having the flow passage port therein. And a case that is provided to be slidable in the axial direction within the case, and slides in one direction to seat on the seat surface,
A valve body having a seal surface that slides in the other direction and separates from the seat surface, a valve body having an outer peripheral surface perpendicular to the seal surface, and a biasing member that biases the valve body in the one direction. In the check valve described above, the attached portion and the fitted portion are prevented from falling off by a retaining device.

In the check valve of the present invention, the retaining means prevents the attached portion such as the concave portion and the fitted portion such as the convex portion from coming off. For this reason, the assembly of the valve seat member and the case does not easily come off, and the function as a check valve can be guaranteed. Therefore, the check valve of the present invention can eliminate the drawbacks of the compressor, the cooling circuit, and the vehicle. As the retaining means, the bottom surface of the storage chamber is brought into contact with the top surface of the case to prevent the case from moving in the direction in which the case comes off, or a step is provided in the storage chamber to move the case in the direction in which the case comes off due to the step. It is also conceivable not to obtain it. However, it is preferable to adopt a diameter expansion preventing means for preventing the diameter of the fitting portion from expanding as the retaining means. In this case, the storage chamber and the like can be molded into a simple shape, and the case can be manufactured from a relatively inexpensive resin molded product having a large tolerance,
The manufacturing cost can be reduced.

The check valve of the present invention is highly effective when used in a cooling circuit including a condenser and a variable displacement compressor having a discharge chamber connected to the condenser. In particular, the effect is greater when the communication port of the check valve is connected to the condenser.
The check valve of the present invention is effective when the variable displacement compressor is operatively connected to an external drive source in a clutchless manner. Prevents accumulation of liquid refrigerant in the compressor, prevents excessive pressure and temperature rise in the compressor, increases the durability of the compressor, increases the tilt angle of the swash plate at startup, and returns capacity This is because the cooling speed can be increased, and a rapid cooling effect can be exerted.

In particular, a variable displacement compressor is effective when it is possible to achieve a discharge capacity of substantially 0%. Here, a compressor capable of realizing a discharge capacity of substantially 0% means a critical angle in which the minimum inclination angle of the swash plate can surely return the angle by the discharge reaction force as disclosed in Japanese Patent Application No. 10-101449. The angle is set to be less than the angle. When the check valve of the present invention is incorporated outside the variable displacement compressor, the retaining means and the diameter preventing means are constituted by components other than the housing of the variable displacement compressor. Preferably, it is incorporated in a variable compressor. In this case, the retaining means and the diameter preventing means can be constituted by the housing or the like of the variable displacement compressor, so that it is possible to prevent an increase in manufacturing cost due to separate parts. Also, if a check valve is provided in the middle of the piping of the cooling circuit, the refrigerant gas that re-expands in the piping on the upstream side of the check valve flows back into the compressor, whereas the check valve is provided in the compressor. This is because such a thing disappears if it is incorporated.

As the diameter expansion preventing means, a flange formed on the case and in contact with the inner wall of the storage chamber can be employed. If such a flange is adopted, the material of the case is reduced as compared with bringing the entire case into contact with the inner wall of the storage chamber,
In addition, it is not necessary to manufacture the whole with high dimensional accuracy, and the manufacturing cost can be reduced. Such a flange may be formed all around the outer peripheral surface of the open end of the case.

When an annular concave portion is employed as one of the attached portion and the fitted portion, and a convex portion which engages with the concave portion is employed as the other of the attached portion and the fitted portion, the flange is formed of the convex portion. Although the function can be exerted to some extent even if it is formed outside, it is easier to prevent the fitting portion from expanding when the flange is formed outside the convex portion. When the attached portion is an annular concave portion and the fitting portion is a plurality of convex portions that engage with the concave portion, the processing when the valve seat member is formed of a highly rigid metal becomes easy, and the case is formed. Can be easily molded with a resin molded product. If these projections are axially symmetric and the flange is formed outside each projection,
The diameter expansion of the fitting portion can be reliably prevented. If the flange is formed only outside each convex part, the material of the case is reduced,
Manufacturing costs can be reduced.

Preferably, the thickness of the flange includes the thickness of the projection. In such a case, the diameter of the case becomes difficult to expand only by the elastic deformation near the convex portion. In particular, such an operation is effective when the case is formed of a resin molded product. It is preferable that a member having a peripheral surface that is press-fitted into the storage chamber be used as the valve seat member, and the outer surface of the flange be flush with the peripheral surface. In this case, the storage chamber can be formed into a simple shape, whereby pressure loss due to the storage chamber can be prevented and the manufacturing cost can be reduced.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the check valve of the present invention is incorporated in a variable displacement swash plate type compressor used in a vehicle air conditioning system will be described below with reference to the drawings. In this compressor, as shown in FIG. 1, a plurality of cylinder bores 1a
A cup-shaped front housing 2 is joined to a front end of a cylinder block 1 in which a cylinder hole 1b, a muffler chamber 1c, and a suction chamber 1d are formed, and a suction valve 3, a valve plate 4, a discharge The rear housing 7 is joined with the valve 5 and the retainer 6 therebetween. Cylinder block 1,
The front housing 2 and the rear housing 7 are made of an aluminum-based metal.

A shaft hole 2a is also formed in the front housing 2, and in a crank chamber 8 formed by the front end of the cylinder block 1 and the front housing 2, a shaft sealing device 9 and a radial bearing 10 are inserted through the shaft hole 2a. The drive shaft 12 is rotatably supported in the shaft hole 1b via a radial bearing 11. In the crank chamber 8, the front housing 2
The lug plate 14 is fixed to the drive shaft 12 via a thrust bearing 13 between the lug plate 14 and the lug plate 14. A pair of arms 15 project from the lug plate 14 toward the rear, and each arm 15 has a guide hole 15a having a cylindrical inner surface. Further, the drive shaft 12 is provided with a through hole 16 of the swash plate 16.
a, and a spring 17 is provided between the swash plate 16 and the lug plate 14. A pair of guide pins 16b project from the front end of the swash plate 16 toward each arm 15, and a guide hole 15 is formed at the tip of each guide pin 16b.
A guide portion 16c having a spherical outer surface that is rotatable while sliding inside a is provided. Further, hollow pistons 19 are provided on the front and rear peripheral edges of the swash plate 16 via a pair of shoes 18, respectively. Each piston 19 is accommodated in each cylinder bore 1a.

A boss 20 is spline-fitted to the drive shaft 12 projecting forward from the front housing 2.
The boss 20 is fixed to the pulley 22 by a key 21. The pulley 22 has a bolt 23
, And is supported by the ball bearing 24 between the front housing 2. A belt 24 connected to the engine EG is wound around the pulley 22.

A spring 26 is provided by a circlip 25 slightly behind the swash plate 16 of the drive shaft 12. The minimum inclination angle of the swash plate 16 is set to be less than a critical angle that enables the angle return by the discharge reaction force to be surely performed. As a result, the moment of the rotational movement acting in the direction of increasing the tilt angle and the moment based on the urging force of the spring 26 cooperate with each other. Cylinder block 1
In the shaft hole 1b, a thrust bearing 27 is provided at the rear end of the drive shaft 12.
And a washer 28, and a spring 29 is provided between the washer 28 and the suction valve 3.

Inside the rear housing 7, there is formed a suction chamber 7a which communicates with a suction chamber 1d of the cylinder block 1 by a suction passage (not shown), and this suction chamber 7a extends through the retainer 6, the discharge valve 5 and the valve plate 4. The suction port 30 communicates with each cylinder bore 1a. The suction chamber 1d is connected by a pipe to the evaporator EV of the cooling circuit, and the evaporator E
V is connected to the condenser CO via an expansion valve V by a pipe. A discharge chamber 7b is provided outside the rear housing 7.
Are formed. A storage chamber 7c is formed behind the discharge chamber 7b, and the storage chamber 7c is communicated with the muffler chamber 1c of the cylinder block 1 by a discharge passage 7d passing through the retainer 6, the discharge valve 5, the valve plate 4, and the suction valve 3. ing. The muffler chamber 1c is connected by a pipe to a condenser CO (not shown) of the cooling circuit. The discharge chamber 7b communicates with each cylinder bore 1a by a discharge port 31 formed through the valve plate 4 and the suction valve 3. Further, the control valve 32 is housed in the rear housing 7, and the check valve 33 is housed in the housing chamber 7c.

In the control valve 32, a cover 42 is fixed to one end of a valve housing 41 as shown in FIG.
One end of 2 is closed by a lid member 43. A pressure-sensitive chamber 44 is provided in the valve housing 41, the cover 42, and the lid member 43.
The bellows 45 is accommodated in the pressure-sensitive chamber 44 so as to be able to expand and contract in the axial direction. A solenoid 47 is fixed to the other end of the valve housing 41 via a fixing member 46. Inside the solenoid 47, a fixed iron core 48 is fixed to the other end of the valve housing 41, and a movable iron core 51 slides in a housing cylinder 49 fixed to the inner surface of the solenoid 47 at the other end of the fixed iron core 48. It is movably provided. The movable iron core 51 has a spring chamber 51a on the other end side, and a spring 50 for urging the movable iron core 51 to one end side is provided in the spring chamber 51a.

The valve housing 41 and the fixed core 48 are provided with a shaft hole 52 extending in the axial direction. The shaft hole 52 is provided between the other end of the valve housing 41 and the fixed core 48 in the valve chamber 53. Is in communication with Bellows 4 in pressure sensing chamber 44
5 and the rod 55 fixed by the fixing member 54
Is slidable in the shaft hole 52, and the rod 5
A valve body 55a located in the valve chamber 53 is fixed at the middle of the valve body 5. A spring 56 is provided between the valve body 55a and one end of the valve chamber 53. The other end of the rod 55 is in contact with one end of the movable iron core 51.

An opening 42 a is formed in the cover 42, so that the pressure sensing chamber 44 and the suction chamber 7 a of the rear housing 7 are communicated with each other through a measurement passage 57. further,
The valve housing 41 has a port 41 a communicating with the shaft hole 52 on the bellows 45 side of the valve chamber 53 and a port 41 b communicating with the valve chamber 53. The shaft hole 52 on the bellows 45 side of the valve chamber 53 and the crank chamber 8 are connected to the port 41a.
Are communicated with each other through an air supply passage 58. The valve housing 41, the fixed core 48, and the movable core 51 have a canceling passage 59 that connects the air supply passage 58 to a spring chamber 51 a in the movable core 51. On the other hand, the valve chamber 53 and the discharge chamber 7b of the rear housing 7 are communicated by an air supply passage 60 via a port 41b. And the solenoid 4
7 is connected to a control computer 6 via a drive circuit 61.
2 are connected. Reference numerals 63 and 64 denote O-rings for accommodating the control valve 32 in the rear housing 7 in an airtight manner.

As shown in FIGS. 3 and 4, the check valve 33 is press-fitted into a storage chamber 7c adjacent to the discharge chamber 7b. As shown in FIG. 3, the storage chamber 7c has a tapered surface 7x that tapers toward the back, and the outer periphery of the tapered surface 7x is formed as a simple cylindrical surface 7y. As shown in FIG. 4, the check valve 33 includes a valve seat member 70, a case 71 fitted to the valve seat member 70 and having a gap between the bottom surface of the storage chamber 7 c, and a shaft 71 in the case 71. A valve body 72 provided slidably in the direction, and a valve body 72 in a case 71
And a spring 73 as an urging member for urging in the direction of. The valve seat member 70 is made of brass, the case 71 and the valve body 72 are injection-molded products of nylon 46, and a spring 73
Consists of spring steel. Thus, the valve seat member 70 and the case 71
The check valve 33 can be manufactured easily, and the manufacturing cost can be reduced.

The valve seat member 70 extends on the outer surface in the axial direction and has a cylindrical surface 7y having a predetermined interference with the cylindrical surface 7y of the storage chamber 7c.
And a positioning portion 70b integrally formed at one axial end of the main body portion 70a and having a tapered surface 70x on the main body portion 70a side that matches the tapered surface 7x of the storage chamber 7c. A small-diameter portion 70d integrally formed while being reduced in diameter at the other axial end of the main body portion 70a, and a seat portion 70e integrally formed while being further reduced in diameter at the other axial end of the small-diameter portion 70d. Consists of

The valve seat member 70 has a flow passage 70f communicating with the discharge chamber 7b. The small diameter portion 70d has an annular concave portion 70c as an adhered portion on the outer peripheral surface. Seat part 70e
Is formed with a seat surface 70g around a flow path opening that opens into the flow path 70f. Further, since the seat portion 70e has a smaller diameter than the small-diameter portion 70d, the recess 70 separates from the outer edge of the seal surface 72a of the valve body 72 around the seat surface 70g.
h.

The case 71 has a flow passage opening of the flow passage 70f formed therein, and a pair of axially symmetric convex portions 71a to be fitted into the concave portion 70c from the outer peripheral side are formed on the inner surface of the opening end. . These convex portions 71a are fitting portions. As shown in FIG. 5, each of the convex portions 7 is formed on the outer surface of the open end of the case 71.
A pair of fan-shaped flanges 71g that are located only outside of 1a and are in contact with the inner wall of the storage chamber 7c are formed. The thickness of each flange 71g is, as shown in FIG.
The outer surface of each flange 71g is flush with the outer peripheral surface of the main body 70a of the valve seat member 70. The flange 71g is a retaining means and a diameter preventing means.

The case 7 on the axial side of the seating surface 70g
A communication port 71b is opened in the peripheral wall of the first connector. Communication port 7
1b has no linear portion extending from the seating surface 70g along the axial direction, is symmetrical with respect to the axial direction, and has the apex angle 71c on the seating surface 70g side and the opposite side 71d on the other side.
It is an isosceles triangle. The communication port 71b is easy to design and practical. Thus, the communication port 71
b is formed such that the opening area thereof is less than the proportional relationship with the lift length of the valve body 72 from the seat surface 70g toward the other direction. Further, a boss portion 71e is provided inside the top surface of the case 71, and a groove 71h is formed in the top surface of the case 71 in a radial direction as shown in FIG. Note that 7
1i is a gate mark at the time of injection molding.

As shown in FIG. 4 and FIG.
It is formed in a substantially cup shape, and has a seal surface 72a that slides in one direction to sit on the seat surface 70g and slides in the other direction to separate from the seat surface 70g as its bottom surface. FIG.
0, the vertex angle 71 of the communication port 71b of the case 71
c coincides with the seal surface 72a when the seal surface 72a of the valve body 72 is seated on the seat surface 70g of the valve seat member 70. On the other hand, the opposite side 71d of the communication port 71b of the case 71 is
The sealing surface 72a of the valve body 72 is the seat surface 70g of the valve seat member 70.
When seated on the valve body 72, the valve body 72 is located closer to the valve seat member 70 than the upper surface of the peripheral wall orthogonal to the seal surface 72a. That is, the outer peripheral surface 72f of the valve body 72 extends from the communication port 71b to the other side when the sealing surface 72a is seated. The gap between the inner peripheral surface of the case 71 and the outer peripheral surface 72f of the valve body 72 is several tens to 200 μm.
m. As shown in FIG. 5, a hole 71f is formed in the groove 71h on the top surface of the case 71 so as to avoid the boss 71e. Thus, as shown in FIG. 10, the damper chamber 71j is formed in the case 71 behind the valve body 72. The spring 73 is held so as not to vibrate between the inner surface of the peripheral wall of the valve body 72 and the outer surface of the boss 71 e of the case 71. Further, as shown in FIG.
An annular groove 72b, which communicates with the communication port 71b at the time of leaving the seat, is recessed in a substantially axial center region of the outer peripheral surface 72f of the second peripheral wall.

The valve body 72 is manufactured as follows. First, as shown in FIG. 7, a first mold 75 having a core portion 75a and a first mold 75 which is located on the outer peripheral side of the core portion 75a and can be opened in a direction away from each other at a mating surface PL extending in the axial direction. Split mold 76 and second split mold 77, and core part 75a
A mold including the second mold 78 located on the top surface side is prepared. Here, as the first split mold 76 and the second split mold 77,
Flat surfaces 76a, 77 orthogonal to the mating surface PL and extending in the axial direction on the side of the cavity C formed by the mold.
The one having a is adopted. The second mold 78 can be opened in the axial direction away from the core part 75a while being located in the first mold 76 and the second mold 77 when the mold is closed. Then, the molten resin is injected into the cavity C, and the valve body 72 is obtained by opening the mold. The obtained valve body 72 is assembled together with the valve seat member 70, the case 71, and the spring 73, which are otherwise prepared, to form the check valve 33.

Here, as shown in FIGS. 6A and 6B, a pair of flat surfaces 72c extending in the axial direction while facing each other are formed on the outer peripheral surface 72f of the peripheral wall of the valve body 72. Is done. The flat surface 72c facilitates gripping, and can prevent erroneous assembly. In addition, the flat surface 72
c, as shown in FIG. 8, a burr 72d projecting outward in a radial direction generated by a mating surface PL of a mold that can remain on the peripheral wall when the valve body 72 is manufactured is securely housed in the circumference thereof.
It is also possible to prevent an adverse effect caused by the 2d getting caught on the inner surface of the case 71. Further, as shown in FIG. 9, a burr 72d protruding in the axial direction caused by a mating surface PL of a mold that can remain on the sealing surface 72a when the valve body 72 is manufactured.
10, as shown in FIG. 10, is securely housed in the recess 70h of the valve seat member 70 to prevent the burrs 72d from being adversely affected by the seat surface 70g. The concave portion 70h of the valve seat member 70 can reduce the area where the seat surface 70g contacts the sealing surface 72a of the valve body 72, so that the valve body 72
Can be improved.

Further, on the upper surface of the peripheral wall of the valve body 72, FIG.
As shown in (B), a groove 72e extending in the radial direction is provided in a concave shape. When the valve body 72 is assembled in reverse, the performance of the check valve 33 is not exhibited due to the groove 72e, and an erroneous assembly can be found in the inspection. In the compressor configured as described above, as shown in FIG. 1, while the engine EG is driven, the pulley 22 is rotated by the belt 24 and the drive shaft 12 is driven. Thereby, the swash plate 16
Swings, and the piston 19 reciprocates in the cylinder bore 1a. Therefore, the refrigerant gas of the evaporator EV of the cooling circuit is sucked into the suction chamber 7a of the compressor, and the cylinder bore 1a
After being compressed inside, it is discharged into the discharge chamber 7b. The refrigerant gas in the discharge chamber 7b is discharged to the condenser CO through the check valve 33 and the muffler chamber 1c.

During this time, the control valve 32 shown in FIG. 2 adjusts the pressure of the bellows 45 in the pressure sensing chamber 44 and the suction passage 57a from the suction chamber 7a under the control of the control computer 62.
Of the discharge chamber 7 by the balance with the suction pressure Ps guided by
The refrigerant gas having the discharge pressure Pd in the b is supplied to the crank chamber 8 through the air supply passage 60, the port 41b, the shaft hole 52, the port 41a, and the air supply passage 58. For this reason, the crank chamber pressure Pc is increased or decreased, and the back pressure acting on the piston 19 is changed. As a result, the inclination angle of the swash plate 16 is changed, and the discharge capacity is changed from substantially 0% to 100%. it can.

In the check valve 33, as shown in FIG. 11, the high-pressure refrigerant gas in the discharge chamber 7b presses the valve body 72 from the flow path 70f in the other direction, and overcomes the urging force of the spring 73. The valve body 72 is slid in the other direction. For this reason, the seal surface 72a separates from the seat surface 70g of the valve seat member 70, and the flow path 7
0f communicates with the communication port 71b. For this reason, the discharge chamber 7
b through the muffler chamber 1c.
O will be discharged.

At this time, in the check valve 33, the case 71
The flanges 71g formed on the inner wall of the storage chamber 7c abut against the inner wall of the storage chamber 7c to reliably prevent the projections 71a from increasing in diameter. In particular, since the thickness of each flange 71g includes the thickness of each convex portion 71a, the case 71 becomes difficult to expand only by elastic deformation near each convex portion 71a. Therefore, the concave portion 70c and the convex portion 71a are prevented from coming off. For this reason, the assembly of the valve seat member 70 and the case 71 does not easily come off. According to the test results of the inventors, the check valve 33 of the embodiment was able to exert a pull-out load approximately twice that of the conventional check valve 94 shown in FIGS. 13 and 14. For this reason, the check valve 33 of the embodiment can guarantee its function.

In the check valve 33, the storage chamber 7c is formed into a simple shape, thereby preventing pressure loss due to the storage chamber 7c and realizing a low manufacturing cost. In addition, the case 71 is manufactured from a resin molded product that is relatively inexpensive but has a large tolerance. Also,
Since a pair of fan-shaped flanges 71g are formed only on the outside of each convex portion 71a, the material of the case 71 is reduced, and it is not necessary to manufacture the whole with high dimensional accuracy, and the manufacturing cost is reduced. Has been realized.

When cooling is not required even while the engine EG is being driven, the control valve 32 stops supplying current from the drive circuit 61 to the solenoid 47 based on a command from the control computer 62. Therefore, the valve body 55a
Is biased by the spring 56, the valve opening of the control valve 32 is maximized, and the high-pressure refrigerant gas in the discharge chamber 7b is supplied to the air supply passages 60, 5 and 5.
Introduced into the crankcase 8 through 8. For this reason, the pressure in the crank chamber 8 increases, the inclination angle of the swash plate 16 is changed to the minimum capacity, and the stroke of the piston 19 decreases. As the discharge flow rate from the piston bore 1a is reduced in this manner, the check valve 33 is connected to the flow path 70f and the communication port 71.
Disconnect communication with b. As described above, when the cooling is unnecessary, the discharge of the refrigerant gas from the compressor is suppressed by the check valve 33, and the compressor is operated with the minimum capacity near 0 capacity.

On the other hand, when the engine EG is stopped, the drive shaft 12 stops, and the control valve 32 does not operate. In the check valve 33, as shown in FIG. 10, the high-pressure refrigerant gas on the condenser CO side pushes the valve body 72 in one direction from the communication port 71b, and the urging force of the spring 73 also helps the valve body 72. Slide in one direction. Therefore, the seal surface 72a is seated on the seat surface 70g of the valve seat member 70, and the communication between the flow path 70f and the communication port 71b is stopped. For this reason, the high-pressure refrigerant gas on the condenser CO side does not flow back into the discharge chamber 7b.

As described above, in the compressor provided with the check valve 33, the backflow of the stopped refrigerant gas can be prevented, so that the storage of the liquid refrigerant in the compressor can be prevented, and the excessive flow in the compressor can be prevented. Pressure rise and temperature rise can be prevented, and the durability of the compressor can be increased. When the engine EG is started again, the drive shaft 12 is driven, and the control valve 32 operates. Further, the check valve 33 discharges the high-pressure refrigerant gas in the discharge chamber 7b to the condenser CO, as shown in FIG.

Thus, during stoppage, the refrigerant gas only in the discharge chamber 7b is supplied to the supply passages 60, 58, the ports 41b, 41a.
And the refrigerant gas supplied to the crank chamber 8 by the shaft hole 52 and flowing backward does not reach the crank chamber 8.
The increase in the pressure of the crank chamber 8 can be suppressed, the inclination angle of the swash plate 16 can be increased at the time of starting, and the capacity can be quickly restored, and a rapid cooling effect can be exerted.

Therefore, in the check valve 33 of the embodiment, the assembly of the valve seat member 70 and the case 71 is hardly disengaged during use, and the drawbacks of the compressor, the cooling circuit and the vehicle can be eliminated.

[Brief description of the drawings]

FIG. 1 is an overall vertical sectional view of a variable displacement swash plate type compressor according to an embodiment.

FIG. 2 is a longitudinal sectional view of a control valve forming a part of the variable displacement type swash plate type compressor according to the embodiment.

FIG. 3 is a front view of a check valve forming a part of the variable displacement swash plate type compressor according to the embodiment.

FIG. 4 is an exploded front view of a check valve according to the embodiment.

FIG. 5 is a plan view of a check valve case according to the embodiment;

FIG. 6A is a bottom view of a valve body of the check valve, and FIG. 6B is a top view of the valve body of the check valve according to the embodiment.

FIG. 7 is a cross-sectional view of a mold for manufacturing a valve body of a check valve according to the embodiment.

FIG. 8 is an enlarged bottom view of the valve element of the check valve according to the embodiment.

FIG. 9 is a partially enlarged side view of a valve body of a check valve according to the embodiment.

FIG. 10 is an enlarged vertical sectional view of a check valve according to the embodiment.

FIG. 11 is an enlarged vertical sectional view of a check valve according to the embodiment.

FIG. 12 is a front view of a check valve forming a part of a compressor according to a conventional embodiment.

FIG. 13 is an enlarged vertical sectional view of a check valve according to a conventional embodiment.

FIG. 14 is an enlarged vertical sectional view of a check valve according to a conventional embodiment.

[Explanation of symbols]

 33 ... check valve 70 ... valve seat member 70f ... flow path 70g ... seat surface 70c ... attached part (recessed part) 71 ... case 71a ... fitting part (convex part) 71b ... communication port 71g ... retaining means, diameter expansion Prevention means (flange) 72 ... valve element 72a ... sealing surface 72f ... outer peripheral surface 73 ... urging member (spring) CO ... condenser EG ... external drive source (engine)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroaki Masukawa 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside the Toyota Industries Corporation (72) Inventor Kazuya Kimura 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Shares F term in Toyota Industries Corporation (reference) 3H051 AA01 BB03 FF08 3H058 AA02 BB29 CD04 EE17 3H076 AA06 BB26 BB40 CC20 CC43 CC84 CC85 CC91

Claims (11)

[Claims] A valve seat member having a flow path having a flow path port, a seat surface formed around the flow path port, and an attached portion formed around the seat surface; A case that has a fitting portion fitted from the side, and a communication port that is opened on a peripheral surface on the axial side from the seat surface, and that has the flow path port opened therein; The seal surface slides in one direction to seat on the seat surface, slides in the other direction and separates from the seat surface, and an outer peripheral surface orthogonal to the seal surface. And a biasing member for biasing the valve body in the one direction, wherein the adhered portion and the fitted portion are prevented from falling off by a retaining means. Characteristic check valve. 2. The check valve according to claim 1, wherein the retaining means is a diameter expansion preventing means for preventing the diameter of the fitting portion from expanding. 3. A cooling circuit comprising a condenser and a variable displacement compressor having a discharge chamber communicating with the condenser, wherein a communication port is communicated with the condenser. The check valve according to claim 1. 4. The check valve according to claim 3, wherein the variable displacement compressor is operatively connected to an external drive source in a clutchless manner. 5. The check valve according to claim 4, wherein the variable displacement compressor is capable of realizing a discharge capacity of substantially 0%. 6. The check valve according to claim 3, wherein the variable displacement compressor has a storage chamber and is incorporated in the storage chamber. 7. The check valve according to claim 6, wherein the diameter expansion preventing means is a flange formed in the case and abutting against an inner wall of the storage chamber. 8. One of the attached portion and the fitted portion is an annular concave portion, the other of the attached portion and the fitted portion is a convex portion engaging with the concave portion, and the flange is formed of the convex portion. The check valve according to claim 7, wherein the check valve is formed outside. 9. The mounting portion is an annular concave portion, the fitting portion is a plurality of convex portions engaging with the concave portion and forming an axial symmetry, and the flange is provided only outside each of the convex portions. 9. The check valve according to claim 8, wherein the check valve is formed. 10. The check valve according to claim 9, wherein the thickness of the flange includes the thickness of the projection. 11. The check valve according to claim 8, wherein the valve seat member has a peripheral surface pressed into the storage chamber, and an outer surface of the flange is flush with the peripheral surface. .