JP2002070745A - Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressor capable of maintaining a filter with little effort. SOLUTION: A shaft inside passage 45 constituting a part of an exhaust passage 41 is formed in a driving shaft 16, and a filter 47 is installed at an inlet 45(a) of the shaft inside passage 45.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor forming a refrigerant circuit (refrigeration cycle) of an air conditioner, for example.

[0002]

2. Description of the Related Art As this type of compressor, there is a variable displacement type compressor capable of changing a discharge capacity. For example, a variable displacement type swash plate compressor as shown in FIG.
Has a configuration in which the inclination angle of the swash plate 102 can be changed by adjusting the internal pressure of the crank chamber 101 that is the swash plate storage chamber. A housing 103 of the compressor is provided with a bleed passage 104, an air supply passage 105, and a control valve 106 for adjusting the internal pressure of the crank chamber 101. The bleed passage 104 connects the crank chamber 101 and the suction chamber 107. The air supply passage 105 is provided between the discharge chamber 108 and the crank chamber 10.
Communicate with 1. The control valve 106 is provided on the air supply passage 105 and is capable of adjusting the opening degree of the air supply passage 105.

By adjusting the opening of the control valve 106, the amount of high-pressure discharge gas introduced into the crank chamber 101 through the air supply passage 105 and the amount of gas discharged from the crank chamber 101 through the bleed passage 104 are increased. The balance with the amount of derived gas is controlled, and the internal pressure of the crank chamber 101 is determined. As a result of the change in the inclination angle of the swash plate 102 in accordance with the change in the internal pressure of the crank chamber 101, the stroke of the piston 109, that is, the displacement of the compressor is adjusted.

A fixed throttle 104a is provided in the bleed passage 104. By narrowing the refrigerant gas flowing through the bleed passage 104 by the fixed throttle 104a,
The internal pressure of the crank chamber 101 can be sufficiently increased without supplying a large amount of high-pressure refrigerant gas from the discharge chamber 108 to the crank chamber 101 via the air supply passage 105. Supplied from the discharge chamber 108 to the crank chamber 101 (leakage)
The refrigerant gas is supplied to the crank chamber 101 and thus the suction chamber 107.
And will be subjected to compression again.
That is, if the amount of the refrigerant gas supplied from the discharge chamber 108 to the crank chamber 101 is large, the efficiency of the air conditioner decreases.

[0005]

However, in the compressor, when the refrigerant gas passes through the bleed passage 104,
There is a problem that foreign matter contained in the refrigerant gas is easily retained at the fixed throttle 104a. In recent years, it has been studied to use carbon dioxide as a refrigerant in an air conditioner. When this carbon dioxide refrigerant is used, the refrigerant pressure is much higher than when a fluorocarbon refrigerant is used. Therefore, in order to prevent the efficiency of the air conditioner from decreasing, the fixed throttle 104 is used.
The diameter of “a” is set to be smaller than that in the case where the chlorofluorocarbon refrigerant is used. For this reason, foreign matters are more likely to be retained in the fixed aperture 104a.

In order to solve the above-mentioned problem, it is conceivable to provide a filter for filtering the refrigerant gas on the bleed passage 104 upstream of the fixed throttle 104a.
However, the amount of foreign matter held in the filter is limited, and it is necessary to periodically perform maintenance such as cleaning and replacing the filter.

An object of the present invention is to provide a compressor that can save the trouble of filter maintenance.

[0008]

According to the first aspect of the present invention, there is provided a compressor in which a drive shaft is rotatably supported by a housing and gas compression is performed by rotation of the drive shaft. A filter is provided on the drive shaft, and a gas path is provided so as to pass through the filter.

In this configuration, the gas flowing through the gas path is filtered by the filter, and foreign matters are removed from the gas. Since the filter is rotated integrally with the drive shaft, an effect of removing foreign substances from the filter by the action of centrifugal force can be expected. Therefore, it is possible to save time and labor for maintenance such as periodic cleaning or replacement of the filter.

A second aspect of the present invention limits the structure of a compressor suitable for applying the first aspect of the present invention. That is, a crank chamber and a cylinder bore are formed in the housing, and the crank chamber houses a cam plate for converting the rotational motion of the drive shaft into a reciprocating motion of a piston housed in the cylinder bore. The inclination angle of the plate with respect to the drive shaft can be changed, and the inclination angle of the cam plate can be changed by adjusting the internal pressure of the crank chamber.

A third aspect of the present invention is characterized in that, in the second aspect, the gas path is for conducting a gas flow related to the adjustment of the internal pressure of the crank chamber. In this configuration, the filter is provided on a gas path involved in adjusting the internal pressure of the crank chamber, in other words, on a gas path involved in controlling the displacement of the compressor. The gas paths involved in controlling the displacement of the compressor tend to be routed at positions where maintenance is difficult to perform, for example, as compared with the main refrigerant path that forms the refrigerant circuit. It is particularly desirable that maintenance of a filter disposed on such a gas path is not required.

According to a fourth aspect of the present invention, in the third aspect, the gas path communicates a crank chamber with a suction chamber formed in a housing. In this configuration, foreign matter in the crank chamber can be prevented from being discharged from the suction chamber to the external refrigerant circuit through the cylinder bore (gas compression process). For example, even if a failure such as a deadlock occurs in the compressor, the external There is no need to replace the circuit.
In other words, when deadlock occurs in the compressor, a large amount of metal chips scraped from each sliding portion exists in the crank chamber. When this reaches the external circuit,
Not only must the compressor be replaced, but also the external circuit.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, a throttle section is provided in the middle of the gas path.
The gas path is characterized in that a filter is disposed upstream of the throttle section.

With this configuration, it is possible to prevent the foreign matter from reaching the throttle section. The invention of claim 6 is the invention of claims 1 to 5
In any one of the above, the drive shaft is provided with an in-shaft passage which forms a part of a gas path, and a filter is provided in the in-coaxial passage.

In this configuration, a filter may be mounted at the entrance, midway, or exit of the in-shaft passage, and a configuration in which the gas path passes through the filter can be easily realized. According to a seventh aspect of the present invention, in the sixth aspect, the inlet or the outlet of the in-shaft passage is opened at an end face of the drive shaft, and the filter is mounted on the end face of the drive shaft so as to cover the opening of the in-shaft passage. It is characterized by having.

In this configuration, the end surface of the drive shaft has more space than the outer peripheral surface, and a relatively large filter can be mounted. Therefore, the setting for increasing the filtering ability of the filter can be easily realized. Further, as compared with the case where the filter is mounted on the outer peripheral surface of the drive shaft, the rotational imbalance of the same drive shaft is less likely to occur.

The invention of claim 8 limits an embodiment particularly suitable for achieving the effects of the invention described in any one of claims 1 to 7. That is, the gas is carbon dioxide used as a refrigerant in a refrigeration cycle.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a variable displacement swash plate type compressor used in a vehicle air conditioner will be described below.

(Variable Capacity Swash Plate Compressor) As shown in FIG. 1, a variable capacity swash plate compressor (hereinafter simply referred to as a compressor).
Is a front housing 1 joined and fixed to a cylinder block 11 via a valve / port forming body 12 at a front end thereof.
3 and a rear housing 14 joined and fixed to the rear end of the cylinder block 11. The cylinder block 11, the front housing 13, and the rear housing 14 constitute a compressor housing. Note that the left side of the drawing is the front and the right side is the rear.

A crank chamber 15 is defined in a region surrounded by the cylinder block 11 and the rear housing 14. A drive shaft 16 is rotatably disposed in the crank chamber 15. The drive shaft 16 is an output shaft (not shown) of an engine (internal combustion engine) E that is a driving source of the vehicle.
And is rotationally driven by the engine E.

The front end of the drive shaft 16 penetrates through the cylinder block 11, the valve / port forming body 12, and the front housing 13 and protrudes to the outside. Drive shaft 16
Is rotatably supported by the cylinder block 11 via a front-side radial bearing 17.
A shaft sealing device 18 is interposed between the front housing 13 and the drive shaft 16.

A housing recess 19 for housing the rear end of the drive shaft 16 is formed in the rear housing 14 in the crank chamber 15. The drive shaft 16 is provided via a rear radial bearing 20 arranged in the accommodation recess 19.
It is rotatably supported by the rear housing 14.

A lug plate 21 is fixed on the drive shaft 16 in the crank chamber 15 so as to be integrally rotatable. A thrust bearing 22 is interposed between the lug plate 21 and the rear housing 14 for receiving an axial load due to a compression reaction force of the refrigerant gas described later. A swash plate 23 as a cam plate is accommodated in the crank chamber 15. The swash plate 23 is supported by the drive shaft 16 so as to be slidable and tiltable. Hinge mechanism 2
4 is interposed between the lug plate 21 and the swash plate 23. Therefore, the swash plate 23 is hinged to the lug plate 21 via the hinge mechanism 24, and the drive shaft 16
, Can be rotated synchronously with the lug plate 21 and the drive shaft 16, and can be tilted with respect to the drive shaft 16 with the sliding movement of the drive shaft 16 in the axial direction.

A plurality of cylinder bores 11 a (only one is shown in the drawing) are formed through the cylinder block 11 so as to surround the drive shaft 16. The single-headed piston 25 is accommodated in each cylinder bore 11a so as to be able to reciprocate. The front and rear openings of the cylinder bore 11a are closed by the valve / port forming body 12 and the piston 25, and a compression chamber 26 whose volume changes in accordance with the reciprocation of the piston 25 is defined in the cylinder bore 11a. Each piston 25 is moored to the outer peripheral portion of the swash plate 23 via a shoe 27. Accordingly, the rotational movement of the swash plate 23 accompanying the rotation of the drive shaft 16 causes the shoe 2 to rotate.
7 is converted into a reciprocating linear motion of the piston 25.

Between the valve / port forming body 12 and the front housing 13, a suction chamber 28 and a discharge chamber 29 are respectively formed. The suction chamber 28 is formed at the center of the front housing 13, and the drive shaft 16 is inserted into the suction chamber 28. The discharge chamber 29 is formed in an annular shape on the outer peripheral side of the suction chamber 28. The refrigerant gas in the suction chamber 28 moves from the top dead center position to the bottom dead center side of each piston 25, and flows through the suction port 30 and the suction valve 31 formed in the valve / port forming body 12 to the compression chamber. Inhaled to 26. The refrigerant gas sucked into the compression chamber 26 is compressed to a predetermined pressure by moving from the bottom dead center position of the piston 25 to the top dead center side, and is discharged to the discharge port 32 formed in the valve / port formation body 12 and the discharge port 32. Discharged into the discharge chamber 29 via the valve 33.

The suction chamber 28 and the discharge chamber 29 are connected by an external refrigerant circuit 35. The external refrigerant circuit 35 and the compressor having the above configuration constitute a refrigerant circulation circuit (refrigeration cycle) of the vehicle air conditioner. Carbon dioxide is used as a refrigerant for the air conditioner.

(Crank Pressure Control Mechanism) As shown in FIG. 1, the crank pressure control mechanism for controlling the pressure (crank pressure) of the crank chamber 15 involved in controlling the inclination angle of the swash plate 23 is a compressor. It is constituted by a bleed passage 41, an air supply passage 42, and a control valve 43 provided in the housing. The bleed passage 41 connects the crank chamber 15 and the suction chamber 28. The air supply passage 42 communicates the discharge chamber 29 with the crank chamber 15, and a control valve 43 is provided in the middle thereof. Although not described in detail, the control valve 43 is formed of, for example, an electromagnetic valve, and is capable of adjusting the opening degree of the air supply passage 42 by external power supply control.

The opening degree of the air supply passage 42 is adjusted by the control valve 43, whereby the amount of high-pressure discharge gas introduced into the crank chamber 15 through the air supply passage 42 and the amount of gas discharged through the bleed passage 41 are increased. The balance with the amount of gas led out from the crank chamber 15 is controlled, and the crank pressure is determined. In accordance with the change of the crank pressure, the difference between the crank pressure via the piston 25 and the internal pressure of the compression chamber 26 is changed, and the inclination angle of the swash plate 23 (the angle formed between the swash plate 23 and a virtual plane orthogonal to the drive shaft 16). As a result, the stroke of the piston 25, that is, the displacement is adjusted.

For example, the control valve 43 (air supply passage 42)
When the opening of the compressor is reduced, the crank pressure decreases, the difference between the crank pressure and the internal pressure of the compression chamber 26 via the piston 25 also decreases, and the swash plate 23 tilts in the direction of increasing the tilt angle, and the compressor Is increased. In FIG.
This indicates a maximum tilt angle state in which the tilt of the swash plate 23 is restricted from contact with the lug plate 21, that is, a maximum discharge capacity state of the compressor.

Conversely, when the opening of the control valve 43 (the air supply passage 42) is increased, the crank pressure is increased, and the difference between the crank pressure and the internal pressure of the compression chamber 26 via the piston 25 is also increased. As a result, the swash plate 23 tilts in the direction of decreasing the tilt angle,
The displacement of the compressor is reduced. In FIG. 1, the imaginary line indicates the minimum inclination angle state in which the inclination of the swash plate 23 is restricted by contact with the minimum inclination angle restriction unit 34 provided on the drive shaft 16, that is, the minimum discharge capacity state of the compressor. I have.

(Bleed passage as gas path) As shown in FIG. 1, an in-shaft passage 45 which forms a part of the bleed passage 41 is formed in the drive shaft 16. Coaxial passage 4
In 5, the inlet 45 a is opened at the rear end face 16 a of the drive shaft 16, and the outlet 45 b is opened at the outer peripheral surface of the drive shaft 16 behind the front radial bearing 17. Therefore, the refrigerant gas in the crank chamber 15 flows through the gap between the thrust bearings 22 and the lug plate 21.
Through the gap between the rear housing 14, the gap between the rear-side radial bearing 20 and the housing recess 19.
To the entrance 45a. Refrigerant gas in the in-shaft passage 45 reaches the suction chamber 28 from the outlet 45b through the gap between the front radial bearing 17 and the gap between the drive shaft 16 and the valve / port forming body 12. This refrigerant path forms a bleed passage 41 as a gas path connecting the crank chamber 15 and the suction chamber 28.

At a position slightly deeper than the inlet 45a in the axial passage 45, a fixed throttle 46 as a throttle portion is provided.
Is provided. The fixed aperture 46 is formed by inserting and fixing another member having a fine hole into the in-shaft passage 45. By narrowing the refrigerant gas flowing through the bleed passage 41 by the fixed throttle 46, the discharge chamber 29 is moved out of the crank chamber 15.
The crank pressure can be sufficiently increased without supplying a large amount of high-pressure refrigerant gas through the air supply passage 42.

Now, as shown in FIG.
A filter 47 is fixed to the rear end face 16a so as to cover the inlet 45a of the in-shaft passage 45. The filter 47 is a disc-shaped element 47 made of, for example, a mesh, a plate having a large number of holes formed thereon, or a porous plate.
a is an annular frame 47b made of synthetic resin or metal
Will be held by. The filter 47 has a frame 47b.
Accordingly, the drive shaft 16 is press-fitted and fixed in a concave portion 16b formed in a rear end surface 16a.

The refrigerant gas flowing through the bleed passage 41 from the crank chamber 15 to the suction chamber 28 is filtered by a filter 47 (element 47a) on the upstream side of the fixed throttle 46. Means that foreign matter contained in the refrigerant gas is retained. For this reason, foreign matter from the crank chamber 15 is
6, the foreign matter is prevented from staying in the fixed throttle 46. The foreign matter held by the element 47a is scattered and removed from the element 47a by the action of the centrifugal force accompanying the rotation of the drive shaft 16.

The present embodiment having the above configuration has the following effects. (1) By disposing the filter 47 on the drive shaft 16, the filter 47 (element 47 a) by the action of centrifugal force
The cleaning effect can be expected. Therefore, it is possible to save time and labor for maintenance such as periodic cleaning or replacement of the filter 47.

(2) A filter 47 is provided on a gas path involved in adjusting the crank pressure, in other words, on a gas path (bleed passage 41) involved in controlling the displacement of the compressor. The gas paths involved in controlling the displacement of the compressor tend to be routed at locations where maintenance is difficult to perform, as compared to the main refrigerant paths that make up the refrigerant circulation circuit (refrigeration cycle). Therefore, it is particularly desirable that maintenance of the filter 47 disposed on such a gas path becomes unnecessary.

(3) The filter 47 is disposed on the bleed passage 41. Accordingly, it is possible to prevent foreign matter in the crank chamber 15 from being discharged to the external refrigerant circuit 35 via the suction chamber 28, the compression chamber 26, and the discharge chamber 29. Even if a failure such as a deadlock occurs in the compressor, for example, In addition, there is no need to replace the external refrigerant circuit 35. In other words, when a deadlock occurs in the compressor, a large amount of metal chips scraped from each sliding portion exists in the crank chamber 15. When this reaches the external refrigerant circuit 35, it is necessary to exchange not only the compressor but also the external refrigerant circuit 35.

(4) Fixed throttle 46 in bleed passage 41
A filter 47 is provided upstream of the filter 47. Therefore, it is possible to prevent foreign matters from remaining in the fixed throttle 46 and consequently to block the bleed passage 41, and to maintain highly accurate discharge displacement control. Further, as described above, since the foreign matter of the filter 47 is removed by the action of the centrifugal force, it is possible to prevent the filter 47 from being clogged and the refrigerant gas from being throttled. This also leads to maintaining high-precision discharge capacity control.

(5) Carbon dioxide is used as a refrigerant for the air conditioner. Therefore, as described in the related art, the diameter of the fixed throttle 46 is set to be smaller than that in the case where Freon refrigerant is used. In such a configuration, a filter 47 is provided upstream of the fixed throttle 46,
It is particularly desirable in terms of the reliability of the compressor to be able to solve the problem of foreign matter staying in 6.

(6) In the drive shaft 16, an in-shaft passage 45 forming a part of the bleed passage 41 is formed, and a filter 47 is provided in the in-coaxial passage 45. Therefore, a configuration in which the bleed passage 41 passes through the filter 47 can be easily realized.

(7) The inlet 45a of the in-shaft passage 45 is opened at the rear end face 16a of the drive shaft 16, and the filter 47 is mounted so as to cover the inlet 45a at the rear end face 16a of the drive shaft 16. Rear end face 16a of drive shaft 16
Has more space than the outer peripheral surface on which the lug plate 21 and the swash plate 23 are arranged, so that a relatively large filter 47 can be mounted. Therefore, the setting for increasing the filtering capacity of the filter 47 can be easily realized. Also,
Compared with the case where the filter 47 is mounted on the outer peripheral surface of the drive shaft 16, the rotational imbalance of the drive shaft 16 is less likely to occur.

(8) The filter 47 includes an element 47a
And a frame 47b holding the same element 47a. The element 47a tends to have insufficient rigidity due to its function, but the insufficient rigidity is compensated for by the frame 47b. Therefore, the filter 47 is connected to the drive shaft 16.
Can be easily adopted, for example, when the element 47a is directly fixed to the drive shaft 16 by brazing or an adhesive (this mode does not depart from the gist of the present invention). Then, the fixing work becomes easy.

The present invention can be practiced in the following modes without departing from the spirit of the present invention. As shown in FIG. 3, the present invention is embodied in a compressor having a configuration in which the suction chamber 28 and the discharge chamber 29 are provided in the rear housing 14. In this case, the valve / port forming body 12 is interposed between the cylinder block 11 and the rear housing 14. Further, in the shaft passage 45, the crank chamber 1
The inlet 45a of the refrigerant gas from the inlet port 5a and the outlet 45b of the refrigerant gas to the suction chamber 28 side are opposite to those of the above embodiment, and the filter 47 is mounted on the rear end face 16a of the drive shaft 16 so as to cover the outlet 45b. I have. Further, the accommodation recess 19 and the suction chamber 28 communicate with each other via a passage 51, and a fixed throttle 51 a as a throttle portion is provided in the middle of the passage 51 (the fixed throttle 46 on the axial passage 45). Is deleted). The embodiment of FIG. 3 has the same effect as the above embodiment. The rear radial bearing 20 is configured to block communication between the crank chamber 15 and the housing recess 19.

The filter 47 is disposed in the axial passage 45. -Arranging the filter 47 on the air supply passage 42. That is, for example, a part of the air supply passage 42 is constituted by the in-shaft passage 45, and the filter 47 is provided in the drive shaft 16 at the inlet 45 a of the in-shaft passage 45, or in the middle or at the outlet 45 b.

The filter 47 is disposed on the suction passage from the external refrigerant circuit 35 to the suction chamber 28 or on the discharge passage from the discharge chamber 29 to the external refrigerant circuit 35. That is, for example, a part of the suction passage or a part of the discharge passage is
And the filter 47 is provided at the inlet 45 a of the drive shaft 16, or in the middle or at the outlet 45 b of the in-shaft passage 45.

Element 47a in the filter 47
Into a three-dimensional shape such as a covered cylindrical shape or a hemispherical shape. By doing so, the surface area of the element 47a can be increased, and the ability of the filter 47 to filter the refrigerant gas increases.

The present invention is embodied in a fixed displacement swash plate compressor. That is, for example, in the above embodiment, the swash plate 2
3 is embodied in a compressor fixed to the drive shaft 16 so as not to tilt.

To be embodied in, for example, a scroll compressor other than the swash plate compressor. The technical idea that can be grasped from the above embodiment and another example will be described. (1) The compressor according to any one of claims 1 to 8, wherein the filter includes an element and a frame that holds the element.

(2) The compressor according to (1), wherein the filter is press-fitted and fixed to a drive shaft with a frame.

[0050]

According to the present invention having the above-described structure, a filter cleaning effect can be expected due to the action of centrifugal force accompanying the rotation of the drive shaft, and the maintenance of the filter can be omitted.

[Brief description of the drawings]

FIG. 1 is a sectional view of a variable displacement swash plate type compressor.

FIG. 2 is an enlarged view of a main part of FIG. 1;

FIG. 3 is a cross-sectional view of a variable displacement swash plate type compressor showing another example.

FIG. 4 is a cross-sectional view of a conventional variable displacement swash plate type compressor.

[Explanation of symbols]

11 ... Cylinder block constituting the housing, 13 ...
Similarly, a front housing, 14 ... a rear housing, 16 ... a drive shaft, 41 ... a bleed passage as a gas path,
45 ... in-shaft passage forming part of the gas path, 47 ... filter.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Naoya Yokomachi 2-1-1 Toyota-cho, Kariya-shi, Aichi F-term in Toyota Industries Corporation (reference) 3H003 AA03 AC03 BG03 CA01 3H076 AA06 BB13 CC36 CC92 CC94

Claims (8)

[Claims] 1. A compressor in which a drive shaft is rotatably supported by a housing, and a gas is compressed by rotation of the drive shaft. A filter is provided on the drive shaft, and the gas is passed through the filter. A compressor provided with a path. 2. A crank chamber and a cylinder bore are formed in the housing, and the crank chamber houses a cam plate for converting the rotational movement of the drive shaft into a reciprocating movement of a piston housed in the cylinder bore. 2. The compressor according to claim 1, wherein the cam plate is capable of changing an inclination angle with respect to a drive shaft, and the inclination angle of the cam plate is changed by adjusting an internal pressure of a crank chamber. 3. The compressor according to claim 2, wherein the gas path is for performing a gas flow involved in adjusting the internal pressure of the crank chamber. 4. The compressor according to claim 3, wherein the gas path communicates a crank chamber with a suction chamber formed in a housing. 5. The compressor according to claim 1, wherein a throttle portion is provided in the middle of the gas path, and a filter is provided upstream of the throttle section in the gas path. 6. The drive shaft according to claim 1, wherein an in-shaft passage forming a part of a gas path is formed in the drive shaft, and a filter is provided in the in-coaxial passage. Compressor. 7. The drive shaft according to claim 6, wherein an inlet or an outlet of the in-shaft passage is opened at an end face of the drive shaft, and the filter is mounted on the end face of the drive shaft so as to cover the opening of the in-shaft passage. The compressor as described. 8. The compressor according to claim 1, wherein the gas is carbon dioxide used as a refrigerant of a refrigeration cycle.