JP2582302Y2 - Swash plate type variable displacement compressor - Google Patents

Description

[Detailed description of the invention]

[0001]

INVENTION The present invention relates to an improvement of the equipped with piston swash plate type variable displacement compressor.

[0002]

2. Description of the Related Art A swash plate type continuously variable displacement compressor suitable for use in vehicle air conditioning is disclosed, for example, in Japanese Patent Application Laid-Open No. 1-138382.
In this type of compressor shown in FIG. 6, a double-headed piston 53 is accommodated in a plurality of bores 52 formed in a cylinder block 51 and a rotary shaft is disposed on an axis parallel to the bore 52. A sleeve 55 is slidably fitted on the rotating shaft 54. A swash plate 57 whose peripheral edge engages with the double-headed piston 53 via a shoe 56 is fitted to the spherical support portion 55a of the sleeve 55 by a matching spherical portion 57a, and is stretched forward of the swash plate 57. A guide pin 58 is attached to the connecting portion 57b,
This is guided by a long hole 54b formed in a front shaft portion 54a of the rotating shaft 54, so that the swash plate 57 can be tilted with the sliding of the sleeve 55. The rear side top dead center position is set so as not to change.

[0003] The compression reaction force of the double-headed piston 53 always acts as a moment M for reducing the inclination angle of the swash plate 57, and this urges the actuating member 60 via the sleeve 55 rightward in the drawing. The activating member 60 is also urged leftward in the figure by the activating pressure supplied to the control pressure chamber 59, so that the inclination angle of the swash plate 57, that is, the discharge capacity of the compressor, is determined by the balance between these opposing urging forces. You. Reference numeral 70 denotes a control valve for selectively adjusting the activation pressure supplied to the control pressure chamber 59. The detection pressure chamber of the control valve 70 is communicated with the swash plate chamber 61 via the pressure detection pipe line a, and the suction pressure is immediately introduced as the detection pressure. In response to the detected pressure, the discharge pressure from the discharge chamber 62 via the high pressure line c is supplied to the control pressure chamber 59 via the supply line b as the actuation pressure, or the pressure in the control pressure chamber 59 is reduced by the low pressure pipe. It is made to escape via the path d, and the operating pressure is reduced accordingly.

[0004]

The lubricating properties of each part of the compressor are ensured by lubricating oil compatible with the refrigerant contained in the refrigerant gas. And a variable displacement compressor may be operated in a small displacement state,
During continuous operation in this small capacity state, the amount of circulating refrigerant is reduced, and poor lubrication of each part becomes a problem.

In the above-described variable displacement compressor, the sleeve 55 is fitted with a small gap (about 10 μm) so that the sleeve 55 can smoothly reciprocate on the rotating shaft 54. There is no room for a refrigerant flow to occur between the shaft 54 and the shaft 54. Therefore, poor lubrication occurs during continuous operation in the small capacity state. The poor lubrication between the sleeve 55 and the rotating shaft 54 hinders the fluctuation of the swash plate tilt angle based on the axial displacement of the sleeve.

The present invention has been made in view of the above circumstances, and a technique for reliably preventing poor lubrication between a sleeve and a rotating shaft and achieving a smooth change in a swash plate inclination angle. It is an issue.

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a cylinder block containing a piston in a plurality of bores, a rotating shaft disposed on an axis parallel to the bore, and a rotating shaft. The sleeve is slidably fitted in the cylinder block, and is formed in the cylinder block, and the refrigerant is introduced from the outside.
A swash plate chamber to be housed in the swash plate chamber, a swash plate which is tiltably pivotally supported in the sleeve, the swash plate chamber through a suction passage
And a suction chamber in which refrigerant of the inner is introduced, in the swash plate type variable displacement compressor for compressing a refrigerant introduced into the bore from the suction chamber by the reciprocating motion of the piston by the rotation of the swash plate, wherein said sleeve lubricating passageway is formed between the rotary shaft,該潤smooth passages, one said suction passage second end with one end communicating with the swash plate chamber communicates with the said suction chamber
It adopts a new technical means of forming a part.

[0008]

In the compressor according to the present invention, a lubricating passage is formed between the sleeve and the rotating shaft existing in the sleeve.
One end of the path is communicated with the swash plate chamber and the other end is
The refrigerant from the swash plate chamber communicates with the suction chamber,
A refrigerant flow is generated through the air to the suction chamber. Therefore , even during continuous operation of the compressor in a small capacity state, the refrigerant is supplied between the sleeve and the rotating shaft, and poor lubrication between the two can be reliably prevented.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a cylinder block 1 is formed by joining a pair of front and rear blocks 1a and 1b to each other. A swash plate chamber 2 is formed in the center of the inside, and a front housing 3 and a rear housing 4 are connected. In the cylinder block 1, a plurality of sets of bores 5a are provided at opposing positions on the front side and the rear side of the swash plate chamber 2.
5b is formed, and a double-headed piston 6 is accommodated in both bores 5a and 5b so as to be able to reciprocate. The cylinder block is provided with a suction port 1c communicating with the swash plate chamber 2.

The cylinder block 1 has a front shaft portion 7a.
, A rear shaft portion 7b, and a flat connecting portion 7c formed therebetween are rotatably supported on an axis parallel to the bores 5a and 5b, and the connecting portion 7c has a long hole. 7d is drilled (see FIG. 4). A sleeve tube 8 is disposed on the rear block 1b so as to be movable along the axis of the rotary shaft 7, and the rotary shaft 7 has a front shaft portion 7a which is connected to the front block via a radial bearing 9a and a thrust bearing 9b. 1a, a rear shaft portion 7b is fitted with a sleeve 10 rotatably supported by the sleeve 8 via a radial bearing 9c. A thrust bearing 9d is interposed between the sleeve 8 and the sleeve 10. The front end of the rear shaft portion 7b of the rotating shaft 7 extends halfway through the sleeve 10, and the front end of the rear shaft portion 7b is
A pressing spring 16 is interposed between the inner end of the pressing spring 16 and the inner end of the pressing spring 16.

The rear shaft portion 7b of the rotary shaft 7 has flat portions 71b, 71b extending over the entire length of the rear shaft portion 7b in the axial direction as shown in a partial perspective view of FIG.
Are formed facing each other. Thereby, the flat portion 7
Two lubricating passages 73, 73 are formed between the sleeves 1b, 71b and the sleeve 10 so as to extend the entire length of the rear shaft portion 7b in the axial direction (see FIG. 3). The opposing direction of the flat portions 71b is the same as the opposing direction of a pair of shaft pins (described later) projecting radially from the base of the sleeve 10. The remaining outer peripheral surface on which the flat portions 71b and 71b are not formed is a curved fitting portion 72 fitted with the sleeve 10.
b and 72b.

At the base of the sleeve 10 located in the swash plate chamber 2, a pair of shaft pins 11 project radially from a pair of through holes 10a formed to face the rear shaft 7b so as to be orthogonal to the rear shaft 7b. The swash plate 12 is supported so as to be tiltable about the shaft pin 11 as a pivot. The swash plate 12 transmits its rotational swinging motion to the double-headed piston 6 as reciprocating motion via the shoe 13, projects forward from the main body 12 a, and is connected to the elongated hole 7 d via the guide pin 15. And the rotational force transmitting portion 12b. Then, based on the axial displacement of the sleeve 10 cooperating with the sleeve 8, the guide pin 15 is guided into the elongated hole 7 d to change the tilt angle of the swash plate 12, and the tilt center is on the rear side of the double-headed piston 6. The top dead center is set so as not to change.

Valve plates 20, 21 are interposed between the cylinder block 1 and the front and rear housings 3, 4, and suction chambers 22, 23 and discharge chambers 24, 25 are formed in the front and rear housings 3, 4. And each discharge chamber 2
Reference numerals 4 and 25 are connected to an external cooling circuit via discharge ports (not shown). Swash plate chamber 2 through front suction passage 26
The front suction chamber 22 communicating with the valve plate 20
The front discharge chamber 24 communicates with the front compression chamber via a discharge valve mechanism (not shown). On the other hand, the rear main suction passage 27 and the lubrication passage 73,
73 and a rear auxiliary suction passage including a communication groove 33a to be described later.
A rear suction chamber 23 which communicates with the swash plate chamber 2 via a rear suction passage formed of a passage also communicates with the rear compression chamber via a similar suction valve mechanism (not shown) provided on the valve plate 21. The discharge chamber 25 is also connected to a rear compression chamber via a discharge valve mechanism (not shown).

A plunger 3 is provided behind the rear suction chamber 23.
A control pressure chamber 32 is formed between the plunger 33 and the rear housing 4 so as to be slidable in the axial direction while abutting on the skirt portion 8 a of the sleeve 8.
The plunger 33 has a rear suction chamber 23 and a cannula 8.
A communication groove 33a communicating with the inside is formed. In addition,
The plunger 33 and the sleeve 8 constitute an actuating member according to the present invention. The control pressure chamber 32 is supplied with a selectively adjusted operating pressure from a control valve 70 via a supply line b. The detection pressure chamber of the control valve 70 is communicated with the swash plate chamber 2 via the pressure detection pipe line a, and the suction pressure is immediately introduced as the detection pressure. Then, according to the detected pressure, the discharge chamber 2
5 through the supply line b to the control pressure chamber 32 via the supply line b as the actuation pressure, or the pressure in the control pressure chamber 32 is released via the low pressure line d. The working pressure is being reduced in conjunction with. The activating pressure supplied to the control pressure chamber 32 in this manner is transmitted to the swash plate 12 via the plunger 33, the sleeve 8 and the sleeve 10, and the swash plate 12 is constantly compressed by the reaction force. The inclination angle of the swash plate 12, that is, the discharge capacity of the compressor is determined by the balance of the forces against the acting moment M.

When the compressor constructed as described above is operated and the rotating shaft 7 rotates, the swash plate 12 rotates integrally with the rotating shaft 7 and swings, and the double-headed piston 6 rotates via the shoe 13. Reciprocates in the bores 5a and 5b. The return refrigerant gas introduced through the suction port 1c enters the swash plate chamber 2 from the inlet with the reciprocation of the double-headed piston 6, and passes through the front suction passage 26, the rear main suction passage 27, and the like to the front side and the rear side, respectively. Guided to the suction chambers 22, 23,
Thus, the air is sucked into the front and rear compression chambers and subjected to a compression action. The refrigerant gas discharged from the compression chambers to the discharge chambers 24 and 25 via a discharge valve mechanism (not shown) is sent out to an external refrigerant gas circuit via a discharge passage.

In the compressor of the present embodiment, lubrication passages 73, 7 are provided between the rear shaft portion 7b of the rotary shaft 7 and the sleeve 10.
3 are formed. The front end side of the lubrication passage 73 communicates with the swash plate chamber 2 through a gap between the front end surface of the sleeve 10 and the rear end surface of the connecting portion 7c of the rotary shaft 7, and the rear end side of the lubrication passage 73 is inside the sleeve 10 and the sleeve. 8 and communicates with the rear suction chamber 23 through the communication groove 33 a of the plunger 33. That is, the lubricating passages 73 , 73 , the inside of the sleeve 10, the sleeve 8
The swash plate chamber 2 and the rear suction chamber 23 communicate with each other through a rear auxiliary suction passage formed of the inside and the communication groove 33a, and the refrigerant from the swash plate chamber 2 is supplied with the lubricant formed by the lubrication passage 73 and the communication groove 33a.
The refrigerant flows to the rear suction chamber 23 through the sub suction passage . For this reason, even during continuous operation of the compressor in a small capacity state, the refrigerant is supplied between the sleeve 10 and the rear shaft portion 7b of the rotary shaft 7, and it is possible to reliably prevent poor lubrication between the two. Become. Therefore, the inconvenience of seizure between the sleeve 10 and the rear shaft portion 7b can be solved, and the smooth sliding of the sleeve 10 with respect to the rear shaft portion 7b realizes a smooth fluctuation of the inclination angle of the swash plate and, consequently, a smooth variable displacement operation of the compressor. it can.

In the above embodiment, the flat portions 71b, 71b of the rear shaft portion 7b are formed so as to face in the same direction as the pair of shaft pins 11 on which the swash plate 12 is pivotally supported. In the direction in which a load acts on the sleeve 10 and the rear shaft portion 7 due to a change in the inclination angle of the swash plate 12, the curved surface fitting portion 72 is provided.
Since the sleeves b and 72b are fitted to the sleeve 10, there is no problem in the structure supporting the load. (Other Examples)
In the above-described embodiment, the configuration in which the flat portion 71b is formed in the rear shaft portion 7b to form the lubrication passage 73 between the rear shaft portion 7b and the sleeve 10 has been described. However, the lubrication passage 73 extends in the axial direction on the outer peripheral surface of the rear shaft portion 7b. A lubricating passage can be formed between the sleeve 10 and the sleeve 10 by forming an appropriate number of straight grooves or spiral grooves. When a plurality of such linear grooves and spiral grooves are formed, it is also preferable to connect the above-described linear grooves and spiral grooves by forming an annular groove at an appropriate position in the axial direction. Further, the straight groove or the spiral groove can be formed in the sleeve 10 side,
FIG. 5 is a sectional view showing an example in which three linear grooves 10b extending in the axial direction are formed in the inner peripheral surface of the sleeve 10 to form a lubrication passage 73 between the sleeve 10 and the rear shaft portion 7b.

A coolant can be guided from the swash plate chamber 2 to the lubricating passage 73 through the through-hole provided in the side surface of the sleeve 10.

[0019]

[Effect of the Invention] As described above, according to the present invention,
Even during the low-capacity operation, the refrigerant is supplied between the rotating shaft and the sleeve, and it is possible to reliably prevent poor lubrication between the two. Therefore, the inconvenience of seizure between the rotating shaft and the sleeve can be eliminated, and the smooth sliding of the sleeve with respect to the rotating shaft can realize a smooth variation of the inclination angle of the swash plate and, consequently, a smooth variable displacement operation of the compressor.

[Brief description of the drawings]

FIG. 1 is a sectional view of a compressor showing an embodiment of the present invention.

FIG. 2 is a partially broken perspective view showing a main part of the compressor.

FIG. 3 is a sectional view showing a sleeve and a rear shaft portion in the compressor.

FIG. 4 is a perspective view showing a rotating shaft in the compressor.

FIG. 5 is a sectional view showing a sleeve and a rear shaft according to another embodiment of the present invention.

FIG. 6 is a sectional view showing a conventional compressor.

[Explanation of symbols]

1 is a cylinder block, 2 is a swash plate chamber, 5a and 5b are bores, 6 is a double-headed piston, 7 is a rotating shaft, 8 is a sleeve, 10 is a sleeve, 12 is a swash plate, 32 is a control pressure chamber, 33 is a plunger, 73 is a lubrication passage.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-232180 (JP, A) JP-A-51-58910 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F04B 27/08

Claims (1)

(57) [Scope of request for utility model registration] A cylinder block accommodating a piston in a plurality of bores; a rotating shaft disposed on an axis parallel to the bore; a sleeve slidably fitted on the rotating shaft; Formed in the cylinder block and externally supplied with refrigerant
A swash plate chamber but that is introduced, is accommodated in the swash plate chamber, a swash plate which is tiltably pivotally supported in the sleeve, via a suction passage
And a suction chamber in which refrigerant of the swash plate chamber is introduced, the swash plate type variable displacement compressor for compressing a refrigerant introduced into the bore from the suction chamber by the reciprocating motion of the piston by the rotation of the swash plate, wherein lubricated passage formed between the sleeve and the rotary shaft,該潤smooth passage is part of the suction passage and the other end with one end communicating with the swash plate chamber communicates with the said suction chamber
Swash plate type variable displacement compressor characterized in that it forms a.