JPH04334777A - Discharge valve device for reciprocating type compressor - Google Patents

Abstract

PURPOSE:To reduce noise and discharging pulsation, and enhance uniform passage of refrigerant in respective ports. CONSTITUTION:Inside a valve plate 6 which partitions a bore 2a, a suction chamber 10, and a discharging chamber 12, there are formed ring-shaped flat valve seat surfaces 6b, 6i whose ports 6a, 6h are opened, and cylindrical-hollow valve chests 6d, 6k surrounded, including retainers 6c, 6j which are opposed to and separated from the valve chests 6b, 6i. Moreover, flat plate type valve bodies 27, 31 are fitted loosely in the valve chests 6d, 6j. When difference pressure is generated in a range between which the ports 6a, 6h are held, the valve bodies 27, 31 moves with the pressure difference to open and close the ports 6a, 6n.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge valve device for a reciprocating compressor suitable for use in vehicle air conditioning.

0002

2. Description of the Related Art As shown in FIG. 11, a conventional discharge valve device for a reciprocating compressor has a port 106 formed in a valve plate 105 that partitions a discharge chamber 103 from a bore 100 where refrigerant is compressed. It is known that a leaf spring-like valve 107 and a retainer 109 are applied to a valve plate 105. In this valve device, the valve is normally closed, and when the differential pressure between the bore 100 and the discharge chamber 103 becomes equal to or higher than the valve opening pressure, the valve 107 is set to move away from the port 106 and open. When the valve is opened, the refrigerant compressed within the bore 100 is transferred to port 1.
00 and is discharged into the discharge chamber 103. In addition, the valve 107
The degree of opening of the valve is regulated by the retainer 109.

0003

[Problems to be Solved by the Invention] By the way, as mentioned above, the above-mentioned general valve device is in a normally closed state, and the differential pressure between the bore 100 and the discharge chamber 103 is equal to the predetermined opening pressure of the valve 107. (elastic force of valve 107), valve 107 opens for the first time. Therefore, the refrigerant in the bore 100 becomes overcompressed.

Furthermore, since the opening speed of the valve 107 increases due to overcompression, there is a limit to the reduction in noise caused by the collision of the valve 107 with the retainer 109. Furthermore, pulsations in the refrigerant discharge pressure are likely to occur. Also, when valve 107 opens, port 1
Since the refrigerant flows from the tip 107a side of the valve 107 of 06, the refrigerant approaches the portion 106a of the port 106 on the tip 107a side, which makes it difficult for the refrigerant to flow uniformly over the entire circumference of the port 106, increasing discharge efficiency. There are also limits.

The present invention utilizes technology to create a discharge valve device that is advantageous in avoiding overcompression as much as possible, reducing noise and discharge pressure pulsation, and is also advantageous in allowing refrigerant to flow throughout the circumference of the port. Take it as a challenge.

[0006]

[Means for Solving the Problems] In order to solve the above problems, the present invention includes a flat valve seat surface in which a port communicating with a compression chamber is opened, and a retainer facing the valve seat surface at a distance. A structure is adopted in which an enclosed valve chamber is formed and a flat plate-shaped valve body is loosely fitted into the valve chamber to open and close the port in response to a pressure difference between regions sandwiching the port.

[0007] The retainer engages with the valve body to regulate the degree of opening of the valve body. The retainer may have a structure in which a plurality of retainers are installed along the outer periphery of the valve chamber at predetermined intervals along the circumferential direction and extend inward, or it may be a ring-shaped retainer with a diameter smaller than the outer diameter of the valve body. It may be a structure that extends. The flat valve body is loosely fitted into the valve chamber and can be seated on a flat valve seat surface. The materials of the flat valve body, retainer, and valve seat surface can be appropriately selected depending on their characteristics, and may be, for example, aluminum-based alloys or iron-based materials. Note that the flat valve body may be solid, or may be hollow in consideration of weight reduction, responsiveness, and the like.

[0008]

[Operation] In the discharge valve device of the present invention, when a pressure difference occurs in the region between the ports, the flat valve body immediately moves within the valve chamber in accordance with the pressure difference, and this causes the valve body to move toward the valve seat surface. The valve body may sit on the valve seat and close the port, or the valve body may move away from the valve seat surface to open the port and hit the retainer.

[0009]

Embodiments Hereinafter, embodiments embodying the present invention will be described with reference to the drawings. (Example 1) As shown in FIG. 1, this swash plate compressor has the following features:
A pair of cylinder blocks 1 and 2 are arranged opposite each other in the front and rear, and a swash plate chamber 4 communicating with a return refrigerant suction port 3 is formed at the joint portion. Both ends of each cylinder block 1, 2 are closed by a front housing 7 and a rear housing 8 via aluminum alloy valve plates 5, 6, respectively. In the front housing 7 and the rear housing 8, suction chambers 9 and 10 are formed on the radially inner side, and ring-shaped discharge chambers 11 and 12 are formed on the radially outer side. The discharge chambers 11 and 12 communicate with a discharge pipe 35 that discharges the discharge refrigerant to the outside of the machine.

[0010] Each cylinder block 1, 2 has a suction passage 3.
8 is formed. The suction passage 38 communicates the swash plate chamber 4 with the suction chambers 9 and 10. Furthermore, each cylinder block 1,
Each cylinder block 1, 2 has a central shaft hole 1f, 2f of 2.
A drive shaft 18 is rotatably supported between radial bearings 14 and 15. The drive shaft 18 passes through the through hole 5u of the front valve plate 5, and the drive shaft 18 passes through the center hole of the ring body 20 held in the front housing 7 via the stopper 16 and the ring seal 16a. has been done. The drive shaft 18 and the ring body 20 are airtightly sealed by a ring-shaped rubber lip seal 19.

A swash plate 23 rotatable within the swash plate chamber 4 is attached to the drive shaft 18, and this swash plate 23 is supported by each cylinder block 1, 2 via thrust bearings 21, 22. Each cylinder block 1, 2 has a plurality of pairs of front and rear bores 1a, 2 arranged in parallel around the drive shaft 18.
A double-headed piston 25, which is moored to the swash plate 23 via a pair of shoes 24, 24, is fitted into each of the bores 1a, 2a so as to be movable in a linear manner.

As shown in FIG. 3, the most characteristic structure of this swash plate compressor is that the rear valve plate 6 has a ring-shaped flat valve seat surface 6b with an open suction port 6a; A valve chamber 6d is formed that is surrounded by a retainer 6c that faces and is spaced apart from the valve seat surface 6b. A flat valve body 27 is loosely fitted into the valve chamber 6d. The suction port 6a communicates the bore 2a and the suction chamber 10 via the valve chamber 6d. Also, Figure 3
As shown in the figure, the rear valve plate 6 includes a ring-shaped flat valve seat surface 6i in which a discharge port 6h is opened, and a retainer 6j that faces the valve seat surface 6i at a distance. Room 6k
is formed. A flat valve body 31 is loosely fitted into the valve chamber 6k. The discharge port 6h is connected to the bore 2 through the valve chamber 6k.
a and the discharge chamber 12 are communicated with each other.

Note that FIG. 4 shows a view in the direction of arrow A in FIG.
shows a view taken in the direction of arrow B in FIG. As shown in FIG. 4, the retainer 6j
are tongue-shaped, and a plurality of them are formed at approximately equal intervals along the outer periphery of the valve chamber 6k. Further, as shown in FIG. 5, a plurality of retainers 6c are also tongue-shaped and are formed at approximately equal intervals along the outer periphery of the valve chamber 6d. Furthermore, as shown in FIG. 1, similar to the case of the valve plate 6, the front side valve plate 5 also has a
A ring-shaped flat valve seat surface 5 with an open suction port 5a
b, and a tongue-shaped retainer 5c facing away from the valve seat surface 5b.
A valve chamber 5d is formed including and surrounding the valve chamber 5d. The suction port 5a communicates the bore 1a and the suction chamber 9 via the valve chamber 5d. A flat valve body 26 is loosely fitted into the valve chamber 5d. Furthermore, a discharge port 5 is provided on the front side valve plate 5.
An enclosed valve chamber 5k is formed including a flat ring-shaped valve seat surface 5i with an opening h and a tongue-shaped retainer 5j spaced apart from and facing the valve seat surface 5i. A flat valve body 30 is loosely fitted into the valve chamber 5k. The discharge port 5h is the valve chamber 5
The bore 1a and the discharge chamber 11 are communicated with each other via k. The above-described valve bodies 26, 27, 30, and 31 are all disc-shaped and made of iron. In addition, the valve chambers 5d, 6d,
Both 5k and 6k are cylindrical spaces.

In this swash plate compressor, when the drive shaft 18 rotates and the swash plate 23 rotates, the piston 25 moves into the bore 1a,
It reciprocates within 2a, and a suction stroke by expanding the volume of the bores 1a and 2a and a compression stroke by reducing the volume of the bores 1a and 2a are performed alternately. Here, as can be understood from FIG. 2, during the suction stroke, the return refrigerant that has returned from the refrigeration circuit to the swash plate chamber 4 in the direction of arrow G through the suction port 3 passes through the suction passage 38 and is directed toward the front side. At the rear side, the air is led out to the suction chamber 9, and at the rear side, it is led out to the suction chamber 10.

Now, with reference to FIGS. 1 and 3, a description will be given of the case where the bore 2a expands in volume and reaches the suction stroke. At this time, since the pressure inside the bore 2a is reduced, a pressure difference is generated, and the rear valve bodies 27 and 31 are moved toward the bore 2a. Therefore, the discharge valve body 31 is seated on the valve seat surface 6i and closes the discharge port 6h, and the suction valve plate 27 hits the retainer 6c to open the suction port 6a. Therefore, the refrigerant in the suction chamber 10 is sucked into the bore 2a, which is in the process of expanding in volume, via the suction port 6a and the valve chamber 6d.

After that, the volume of the bore 2a is reduced, so the pressure inside the bore 2a is increased, and as shown in FIG.
1 is placed on the discharge chamber 12 side, and the suction valve body 27 is placed on the suction chamber 10 side. Therefore, as shown in FIG. 6, the suction valve body 27 seats on the valve seat surface 6b and closes the suction port 6a, and the discharge valve body 31 hits the retainer 6j and opens the discharge port 6h. Therefore, the compressed refrigerant in the bore 2a is discharged into the discharge chamber 12 via the discharge port 6h.

Similarly, regarding the suction valve body 26 and the discharge valve body 30 of the front side valve plate 5, the valve chamber 5d changes depending on the pressure difference between the bore 1a, the suction chamber 9, and the discharge chamber 11. ,5k
The suction port 5a and the discharge port 5h are opened and closed. The compressed refrigerant discharged into the discharge chambers 11 and 12 is guided to a discharge passage 35a shown in FIG. 2, and is discharged from a discharge pipe 35 to a refrigeration circuit outside the machine. In this way, the refrigerant circulates through the refrigeration circuit.

By the way, in this swash plate type compressor, as mentioned above, the suction valve body 27 and the discharge valve body 31 of the rear side valve plate 6 are located at the difference between the bore 2a, the suction chamber 10, and the discharge chamber 12. The rear suction port 6a and the discharge port 6h are opened and closed depending on the pressure. Similarly, in the front side valve plate 5, the suction valve body 26 and the discharge valve body 30 are connected to the front side suction port 5a, the discharge valve body 30 depending on the differential pressure between the bore 1a, the suction chamber 9, and the discharge chamber 11. Open/close port 5h.

Therefore, the response when opening the valve is improved compared to the conventional device shown in FIG. 11, which is advantageous in reducing or avoiding overcompression of the refrigerant that has conventionally occurred. Furthermore, since the responsiveness when opening the valve is improved, it is also advantageous in reducing pulsations in the discharge pressure. According to an actual machine test, when the rotation speed of the drive shaft 18 was 3000 rpm, in the conventional device shown in Fig. 11, the overcompression was 12 kgf/cm2 and the noise level was 72 dB, whereas with this device, the overcompression was 12 kgf/cm2 and the noise level was 72 dB. was 7 kgf/cm2, and the noise level was 66 dB, indicating that both overcompression and noise were reduced.

Moreover, since each valve body 27, 31, 26, 30 is loosely fitted into the valve chamber 6d, 6k, 5d, 5k, the refrigerant flows over the entire circumference of each valve body 27, 31, 26, 30. Therefore, the refrigerant can flow through each port 6a, 6h,
It can flow over the entire circumference area of 5a and 5h. Therefore, it is advantageous to improve the uniformity of refrigerant flow in each port 6a, 6h, 5a, 5h.

Further, in this swash plate compressor, as shown in FIG. 3, the surface 6x of the rear valve plate 6, the suction side retainer 6c, and the discharge side retainer 6j are almost flush with each other, and the suction side valve Both the chamber 6d and the discharge side valve chamber 6k are formed inside the valve plate 6. Similarly, on the front side, the valve chambers 5d, 5
k is formed inside the valve plate 5. Therefore, it is advantageous for downsizing the valve device and, by extension, the swash plate compressor. Furthermore, as described above, the surface 6x of the rear valve plate 6 and the suction side retainer 6c are substantially flush with each other, and as can be understood from FIG. The plate 6 can be approached, which is advantageous for improving the compression ratio in the bore 2a. Similarly, bore 1a
During the compression stroke, the piston 25 can approach the valve plate 5, which is advantageous for improving the compression ratio in the bore 1a.

(Other Embodiments) Furthermore, in the swash plate compressor of the first embodiment described above, the valve chambers 5d and 5k are formed inside the front side valve plate 5, and the valve chambers 6d and 6k are formed inside the valve plate 5 on the front side. Although it is formed inside the rear side valve plate 6, it is not limited to this.
As shown in Embodiment 2 shown in FIG. 7, retainers 5c, 5j, 6c, and 6j may be formed to protrude from valve plates 5 and 6.

Furthermore, as in the third embodiment shown in FIGS. 8 and 9, the retainer 45 of the valve device is composed of a ring portion 45a and a plurality of fixing portions 45b extending radially from the ring portion 45a. It's okay. The outer diameter of the ring portion 45a is slightly smaller than the outer diameter d1 of the valve body 26. In this case, the fixing portion 45b is fixed by being press-fitted into the groove 5r of the valve plate 5 or by welding. In this example, since the valve body 26 contacts the entire ring portion 45a of the retainer 45 when the valve is opened, surface contact is improved, the posture of the valve body 26 is stabilized when the valve is opened, and the retainer 45 is deflected. This is advantageous in avoiding wear. In this way, when the posture of the valve body 26 becomes stable when opening the valve,
Even when the valve is closed after being opened, the valve body 26 is easily seated on the valve seat surface 5b, and the posture of the valve body 26 is stable even when the valve is opened again after being seated. Therefore, it is more advantageous in suppressing pulsation. In addition, according to the actual machine test, the drive shaft 18
When the rotation speed is 3000 rpm, the discharge pulsation is 0.09 kgf/cm2 in the compressor with the structure shown in Figs.
On the other hand, in the compressor using the valve device shown in FIGS. 8 and 9, the discharge pulsation was reduced to 0.06 kgf/cm2.

Note that this retainer 4 shown in FIGS. 8 and 9
5 can be made of a material with good wear resistance, such as steel. Further, in order to reduce the sound of the valve body 26 hitting the retainer 45, the retainer 45 can be coated with an elastic layer made of an elastic material. Further, in the examples shown in FIGS. 8 and 9, the retainer facing the valve body 26 is improved, but it goes without saying that the retainers facing the other valve bodies 27, 30, and 31 may have a similar structure. It is.

Furthermore, as in the fourth embodiment shown in FIG. 10, the retainer 47 may be constructed of a central portion 47a, a fixing portion 47b extending radially from the central portion 47a, and an extending portion 47c. In this case as well, the fixing portion 47b is fixed by being press-fitted into the groove 5r of the valve plate 5 or by welding. In the case of this example, since the valve body 26 hits the central part 47a, radial fixing part 47b, and extension part 47c of the retainer 47 when the valve is opened, the surface contact property is improved, and the example shown in FIGS. 8 and 9 Similarly, the posture of the valve body 26 is stabilized when the valve is opened, which is advantageous in avoiding uneven wear of the retainer 45. Further, as described above, since the posture of the valve body 26 is stabilized when the valve is opened, the valve body 26 is easily seated on the valve seat surface 5b even when the valve is closed after opening.

[0026]

According to the valve device for a reciprocating compressor of the present invention, the flat plate-shaped valve element opens and closes the port in immediate response to the differential pressure between the ports. Therefore, the response when opening the valve is improved compared to the conventional device having a leaf spring-shaped valve 107 as shown in FIG. Therefore, it is advantageous to reduce or avoid overcompression of refrigerant and pulsation of discharge pressure, which conventionally occur.

Moreover, since the flat valve body is loosely fitted into the valve chamber, a ring-shaped passage is formed between the inner wall surface of the valve chamber and the outer surface of the valve body, so that the refrigerant can flow between the valve body and the port. The refrigerant can flow over the entire circumference, which is advantageous in improving the uniformity of the refrigerant flow and improving the discharge efficiency.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a swash plate compressor according to a first embodiment.

FIG. 2 is a cross-sectional view of the swash plate compressor of Example 1.

FIG. 3 is a sectional view of main parts showing the action.

FIG. 4 is a view taken along arrow A in FIG. 3;

FIG. 5 is a view taken along arrow B in FIG. 3;

FIG. 6 is a sectional view of main parts showing the action.

FIG. 7 is a cross-sectional view of essential parts according to the second embodiment.

FIG. 8 is a plan view of main parts according to the third embodiment.

FIG. 9 is a cross-sectional view of essential parts according to Example 3.

FIG. 10 is a plan view of main parts according to the fourth embodiment.

FIG. 11 is a sectional view of a conventional device.

[Explanation of symbols]

In the figure, 5 and 6 are valve plates, 5a and 6a are suction ports, 5h,
6h is a discharge port, 5b, 6b are valve seat surfaces, 5i, 6i are valve seat surfaces, 5c, 6c are retainers, 5j, 6j are retainers, 5d, 6d are valve chambers, 5k, 6k are valve chambers, 26, 27 ,
30 and 31 indicate flat valve bodies.

Claims (1)

[Claims] Claims: 1. An enclosed valve chamber including a flat valve seat surface having an open port communicating with a compression chamber and a retainer spaced apart from and facing the valve seat surface; A discharge valve device for a reciprocating compressor, in which a flat plate-shaped valve body is loosely fitted to open and close a port in response to differential pressure between the ports.