JPH01232180A - Variable displacement swash plate type compressor - Google Patents

Abstract

PURPOSE:To make improvements in lubricating ability by forming a feed oil passage, being opened to a tilting groove in a flat plate part of a shaft, in a shaft axial direction. CONSTITUTION:A tilting groove 166 is formed in a flat plate part 165 of a shaft 1, and a swash plate 10 is rockably connected to the shaft via this groove 166. In this shaft 1, there are provided with a feed oil passage 701 extending in its axial direction and an oil filler hole 703 extending the radial direction. Lubricating oil flows into the tilting groove 166 relatively, largely opened to the shaft 1, flowing in the axial direction in the shaft 1 via the feed oil passage 701, and afterward, it is fed toward a shaft outer surface from an oil filler hole 703 by dint of centrifugal force. In consequence, even if a special oil feeding mechanism is not installed there, the lubricating oil is favorably feedable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to capacity control of a swash plate compressor, and is effective when used as a refrigerant compressor for an automobile air conditioner, for example.

[Problem to be solved by the invention]

The present inventors previously developed a variable displacement swash plate compressor in which a swash plate that is rotationally driven by a shaft decreases its inclination angle in accordance with the axial movement of the spool, thereby reducing the stroke of the piston. We proposed a variable configuration. That is, the swash plate is attached to the shaft so as to be tiltable and displaceable in the axial direction of the shaft, and the inclination angle and center position of the swash plate are moved in conjunction with each other.

In such a variable capacity swash plate compressor, although there is a significant increase in dead volume in one working chamber as the swash plate inclination angle changes, there is no significant increase in dead volume in the other working chamber. , the capacity can be gradually reduced.

FIG. 2 is a sectional view showing a variable capacity swash plate compressor previously proposed by the present inventors. In this example, the swash plate 10 changes its inclination angle in accordance with the displacement of the spool 30. Furthermore, since the swash plate lO is tiltably connected to the spherical support portion 405 of the spool, the tilt angle of the swash plate 10 is varied according to the displacement of the spool 30. By controlling the pressure within the pressure chamber 200, the position of the spool 30 is displaced, and thereby the discharge capacity of the compressor can be continuously and variably controlled.

The present invention relates to the improvement of the compressor previously proposed by the present inventors, and particularly aims to improve the lubricity of the rotating parts of the sliding part 9, etc.

[Configuration and operation]

In order to achieve the above object, in the compressor of the present invention, an inclined groove is formed in the shaft, and the swash plate is swingably connected to the shaft via the inclined groove. A configuration is adopted in which an oil supply passage extending in the axial direction and an oil supply hole extending in the radial direction are provided.

With this configuration, the lubricating oil contained in the refrigerant that has flowed into the compressor flows into the inclined groove that has a relatively large opening in the shaft. The lubricating oil that has flowed into this inclined groove then flows in the shaft direction through the oil supply passage, and is then supplied from the oil supply hole toward the outer surface of the shaft by centrifugal force. As a result, in the compressor of the present invention, lubricating oil can be supplied satisfactorily by the centrifugal force generated by the rotation of the shaft, without the need for a special oil supply mechanism such as an oil pump.

Accordingly, in the compressor of the present invention, the parts to be lubricated are well lubricated, and smooth operation can be ensured even during high-speed rotation.

〔Example〕

An embodiment of the present invention will be described below based on the drawings.

FIG. 1 is a longitudinal sectional view of a variable displacement swash plate compressor. Aluminum alloy front housing 4° front side plate 8. Suction valve9. Front cylinder block 5. Rear cylinder block 6° intake valve 12. Rear side plate 11 and rear housing 13 are through bolts 1
6 forms the outer shell of the compressor which is integrally fixed. As shown in FIG. 3, the cylinder block 5.6 is provided with five cylinders 64 (641 to 645), each of which is parallel to the other. A shaft l that rotates under the driving force of an automobile engine (not shown) is connected to a front housing 4 and a rear housing 13 via bearings 3 and 14, respectively.
It is rotatably supported on the shaft. Further, the thrust force (force acting in the left direction in the drawing) applied to the shaft 1 is received by the front cylinder block 5 via the thrust bearing 15, thereby regulating the movement of the shaft 1 in the right direction in the drawing.

The thrust force acting on the slide portion 40 (the force acting in the right direction in the figure) is received by the spool 30 via the thrust bearing 116,
The annular locking portion 17 prevents the slide portion 40 from coming off the spool 30.

Note that this locking portion 17 is formed on the outer surface of the thrust portion 40. The spool 30 is arranged slidably in the axial direction within the cylindrical portion 65 of the rear cylinder block 6 and the cylindrical portion 135 of the rear housing 130.

Further, a slit 105 is formed on the side surface of the shaft 1 of the swash plate 10, and a flat plate portion 165 is formed on the end surface of the shaft 1 on the swash plate 10 side. By disposing the flat plate portion 165 in surface contact with the inner wall of the swash plate 105, the rotational driving force applied to the shaft 1 is transferred to the swash plate 10.
It is something that can be conveyed to people.

Furthermore, shoes 18 and 19 are slidably disposed on both sides of the swash plate 10. On the other hand, a piston 7 is slidably disposed within the cylinder 64 of the front cylinder block 5 and the cylinder 64 of the rear cylinder block 6. As described above, the shoes 18 and 19 are slidably attached to the swash plate lO. Furthermore, the shoes 18 and 19 are rotatably engaged with the inner surface of the piston 7. Therefore, the rocking motion accompanying the rotation of the swash plate lO is transmitted to the piston via the shoes 18 and 19 as a reciprocating motion. The shoes 18 and 19 are formed so that their outer surfaces lie on the same spherical surface when assembled on the swash plate 10.

The flat plate portion 165 of the shaft 1 is provided with an inclined groove 166, and the swash plate 10 is provided with a pin hole. After the flat plate portion 165 of the shaft 1 is arranged in the slit 105 of the swash plate 10, it is locked in the pin passage hole and the inclined groove 166 of the shaft 1 by the pin 80 and the retaining ring. In this example, the pin 80 is made up of a bottle core material 801 and a cylindrical sliding material 802 fitted to the surface thereof.

The inclination of the swash plate changes depending on the position of the pin 80 in the inclined groove 166, so as the inclination changes, the center position of the swash plate also changes.
0, even if the inclination of the swash plate 10 changes and the stroke of the piston 7 changes, the top dead center of the piston 7 on the working chamber 60 side hardly changes, and the slope is such that there is virtually no increase in dead volume. A groove 166 is provided. On the other hand, in the working chamber 50 on the left side in the figure, the top dead center of the piston 7 changes as the inclination of the swash plate changes, so the dead volume also changes.

Further, oil supply passages 701 and 702 are formed in the center of the shaft 1 along its axis. Refueling passage 701,
One end of each of the grooves 702 opens into the inclined groove 166. The shaft also has oil supply holes 70 in the radial direction.
3,704 are formed, and one end of this oil supply hole opens into the oil supply passage 701 and 702, and the other end opens into the outer surface of the shaft l. In particular, the oil supply holes 703 and 704 are opened at portions of the compressor where lubricating oil needs to be supplied. In this example, the oil supply hole 703 is connected to the shaft sealing device 21.
The oil supply hole 704 is formed in the slide portion 40 .

Furthermore, an oil supply hole 705 is formed in the slide portion 40 in the radial direction, and the lubricating oil supplied from the oil supply hole 704 is
Further, centrifugal force causes the oil to flow through the oil supply hole 705.

The shaft sealing device 21 is attached to the front housing 4 in order to prevent refrigerant gas and lubricating oil from leaking to the outside along the shaft 1. Reference numeral 24 in the figure indicates the working chamber 50.
60 and is a discharge port communicating with the discharge chamber 90° 93, and this discharge port 24 is opened and closed by a discharge valve 22. The discharge valve 22 and a valve holder 23 are fixed to the front side plate 8 and the rear side plate 11 with bolts (not shown). The symbol 25 in the figure is the working chamber 50°6
0 and the suction chamber 72, 74, the suction valve 9
and is opened and closed by the suction valve 12.

Reference numeral 500 in the figure is a control valve for controlling the internal pressure of the control pressure space 200, and one side of the control valve 500 is connected to the suction pressure space 69 at the rear end of the shaft 1 through a low pressure introduction passage 97. The other end is connected to the control pressure chamber 200 via a control pressure passage 98 and communicates with the discharge chamber 93 via a high pressure introduction passage 96 and a throttle 99.

A discharge space 90 on the front side in FIG. 1 is led to a discharge boat by a discharge passage (not shown) formed in the cylinder block 5, and a discharge space 93 on the rear side is led to a discharge boat by a discharge passage formed in the cylinder block 6. being guided by a boat. Since the redischarge boat is connected by external piping,
The internal pressures of the discharge space 90 and the discharge space 93 are the same pressure.

The front suction space 72 is led to the suction space 70 formed in the center of the housing by a suction passage 71, and the rear suction space 74 is similarly led to the suction space 70 by a suction passage 73.

The operation of the compressor with the above configuration will be described.

When an electromagnetic clutch (not shown) is connected and driving force from the engine is transmitted to the shaft 1, the compressor starts.

Since no pressure difference occurs inside the compressor at startup, no pressure difference occurs before and after the spool 30 in this state. That is, at the time of startup, the slide portion 4
No load is applied in the direction of tilting the swash plate 10 through 0.

When the shaft 1 starts rotating in this state, the rotation of the shaft 1 causes the piston 7 to reciprocate via the swash plate 10. As the piston 7 moves back and forth, the refrigerant is sucked, compressed, and discharged within the working chamber 50, 60.

However, in this case, a force based on the pressure difference between the rear working chamber 60 and the front working chamber 50 is applied to the swash plate 10 via the piston 7 and the shoes 18, 19. In particular, the swash plate 10 is swingably supported by the spherical support part 4.05, and receives the rotational force of the shaft 1 by fitting the slit 105 and the flat plate part 165. The applied force acts as a moment in the direction of decreasing the angle of inclination of the swash plate lO.

For example, when the transmission pin 80 is located on the axis X in FIG. 3, the piston disposed in the first cylinder space 641 does not generate a moment that changes the inclination angle with respect to the swash plate IO. However, a rotational moment is generated from the pistons 7 disposed in the second to fifth cylinder spaces 642, 643, 644, and 645 in a direction that reduces the inclination angle of the swash plate 10. This rotational moment will be absorbed by the moment generated around the bin 80. Further, the rotational moment generated by the piston 7 applies a pressing force to the spherical support portion 405.

In other words, when there is no differential pressure across the spool 30,
The slide portion 40 and the spool 30 are displaced to the right in the figure. As a result, the swash plate 10 reduces its angle of inclination.

However, since the swash plate 10 is regulated by the transmission pin 80 in the inclined groove 166 of the shaft l, the swash plate 10 reduces the inclination and applies a force to the center of the swash plate 10 in the left direction in the figure. The center position of the swash plate 10 is moved to the right. The force acting on the slide portion 40 (the force in the right direction in the figure is caused by the thrust bearing 116
, and the spool 30 moves until it hits the bottom of the rear housing 13. This state is the state in which the discharge capacity of the compressor is at its minimum.

The refrigerant gas sucked through the suction port 710 (connected to the evaporator of the refrigeration cycle) enters the suction space 70 in the center, then passes through the suction passage 73 and enters the suction chamber 74 on the rear side. Thereafter, during the suction stroke of the piston 7, the air is sucked into the working chamber 60 from the suction port 25 via the suction valve 12. The sucked refrigerant gas is compressed in the compression stroke,
When compressed to a predetermined pressure, the discharge valve 22 is pushed open through the discharge port 24 and the discharge chamber 93 is discharged. The high-pressure refrigerant gas passes through the discharge passage and is discharged from the discharge port to a condenser (not shown) of the refrigeration cycle.

At this time, since the first working chamber 50 on the front side has a large dead volume, the compression ratio is smaller than that of the second working chamber 60 on the rear side, and the pressure of the refrigerant gas in the first working chamber 50 is lower than that in the discharge space 90. The pressure is lower than the pressure (from which the discharge pressure of the second working chamber 60 on the rear side is led), and the action of sucking and discharging refrigerant gas in the first working chamber 50 on the front side is not performed.

Note that the suction boat 710 opens at approximately the middle position of the cylinder block 5°6, and the refrigerant sucked from the suction boat 710 comes into direct contact with the center of the swash plate 10 and the flat plate portion 165 of the shaft 1. . Here, in a compressor used in an air conditioner, it is known that lubricating oil is mixed into the refrigerant and various parts are lubricated with the lubricating oil.

In particular, since the volume of the suction space 70 of the compressor increases rapidly compared to that of the refrigerant piping, lubricating oil is easily separated from the refrigerant sucked into the compressor. Moreover, most of the refrigerant is contained in the flat plate portion 165 of the shaft l.
Therefore, the lubricating oil, which has a larger mass than the refrigerant, comes into direct contact with the flat plate portion 165. Therefore, the lubricating oil contained in the refrigerant is likely to condense on the flat plate portion 165.

Moreover, in the compressor of this example, the inclined groove 166 is formed in this flat plate part, and since this inclined groove has a large opening area, the lubricating oil that has dew on the flat plate part 165 is absorbed into this inclined groove. 166.

The lubricating oil that has flowed into the inclined groove 166 then flows into the oil supply passage 7.
01,702 in the axial direction. Here, the fuel supply passage 70
Since the oil supply holes 703, 704 are open in the oil supply holes 703, 702, the lubricating oil in the oil supply passages 701, 702 flows outward from the oil supply holes 703, 704 due to centrifugal force. Therefore, the lubricating oil that has flowed into the inclined groove 166 flows through the oil supply passages 701 and 702, and flows through the oil supply holes 703 and 704.
This means that the oil is supplied to non-lubricated parts of the compressor.

In this example, since the oil supply hole 703 opens near the shaft seal device 21, the sealing surface of the shaft seal device is smoothly cooled and lubricated. Further, since the oil supply hole 704 is open on the inner surface of the slide portion 40, the slide portion 40 can smoothly slide along the outer surface of the shaft 1.

Furthermore, an oil supply hole 705 is formed in the slide part 40 in the radial direction, and this oil supply hole 705 allows the slide part 40 to
This means that the spherical support portion 405 is smoothly lubricated.

When the compressor is started, the compressor discharge capacity becomes the minimum capacity as described above. However, in this state where the suction pressure is equal to the discharge pressure, the absolute pressure of the refrigerant in the suction pressure chamber 74 is also higher than the set pressure. Therefore, the pressure introduced into the pressure chamber 501 by the low pressure introduction passage 97 is higher than the set pressure of the control valve 500, and as a result, the control valve 500 communicates the high pressure introduction passage 96 and the control pressure passage 98.

Similarly, it is known that even after the compressor is operated, the pressure inside the suction chamber 74 of the compressor increases when the required capacity of the refrigeration cycle is higher. This is due to superheating in the evaporator of the refrigeration cycle, and if the pressure of the refrigerant sucked into the compressor increases in this way, the control pressure chamber 200 will flow through the high pressure introduction passage 96 as in the case of startup described above. It is electrically connected to the discharge chamber 93. Therefore, the high pressure within the discharge chamber 93 is gradually introduced into the control pressure chamber 200 via the throttle 99. As a result, the pressure within the control pressure chamber 200 gradually increases.

Therefore, a force acting on the spool 30 in the left direction in FIG. 1 (due to the pressure difference between the control pressure chamber 200 and the suction space 74)
gradually increases as the compressor rotates. When this force overcomes the force pushing the slide portion 40 to the right in the figure, the spool 30 gradually begins to move to the left in the figure. Then, due to the action of the inclined groove 166 of the shaft l and the transmission pin 80, the inclined Fi 10 moves its center of rotation to the left in the figure and increases its inclination. Further control royal family 20
As the internal pressure increases, the spool 30
05 moves to the left in the figure until it hits the rear side plate 11, achieving the maximum capacity state. In this state, refrigerant gas sucked through the suction port 710 enters the central suction space 70, passes through the suction passages 71 and 73, and flows into the suction chambers 72 and 74, respectively. In the suction stroke, the air enters the working chambers 50 and 60 from the suction port 25 through the suction valves 9 and 12, respectively, and is then compressed with the displacement of the piston 7, and flows from the discharge port 24 through the discharge valve 22 into the discharge space. It enters 90 and 93, passes through the discharge passage, is discharged from the discharge boat, and joins with the external piping.

In this state, both the working chambers 50 and 60 suck refrigerant gas,
Performs a discharge action.

After that, the compressor discharge capacity required from the refrigeration cycle decreases (and the pressure of the refrigerant sucked into the compressor decreases accordingly. This is due to an increase in the amount of restriction of the expansion valve.

In this state, the signal pressure passage 98 and the low pressure introduction passage 97 are electrically connected. As a result, the pressure within the control pressure chamber 200 is released to the suction pressure space 69 side. As a result, the pressure difference occurring before and after the spool 30 is reduced, and the spool is displaced to the right in FIG. 1 due to the same pressure state as described at the time of startup described above.

That is, in the compressor of this example, the spool 30 is continuously displaced according to the pressure of the refrigerant sucked into the compressor, and thereby the discharge capacity of the compressor is also continuously changed.

In this way, in the compressor of this example, the discharge capacity of the compressor can be continuously variably controlled from the minimum capacity to the maximum capacity according to the control of the control valve 500.

Moreover, in the compressor of this example, the inclined groove 166 is connected to the suction space 70.
Since the opening is in the middle of the
It is easy for the liquid to flow into the inclined groove 166. The lubricating oil that has flowed into the inclined groove 166 is then transferred to the oil supply passage 701.
702 and feed holes 703, 704 to the non-lubricated points of the compressor. Therefore, each part of the compressor is smoothly lubricated over the entire compressor discharge capacity from a small capacity state to a large capacity state.

In the example described above, the oil supply passages 701 and 702 are formed on both the front side and the rear side of the shaft, but they may be formed only on the rear side, for example. Further, the positions of the oil supply holes 703 and 704 are not limited to the above example, and may be set at other locations so as to open toward the compressor oil supply location. Conversely, in the above example, the oil supply hole 705 was also provided in the slide portion 40, but this oil supply hole 705 may be omitted if necessary. -Furthermore, the oil supply hole 704°70
5 may be formed from the oil supply passages 701, 702 toward the outer surface of the shaft. Therefore, the oil supply holes 704, 70
5 does not necessarily need to be perpendicular to the oil supply passages 701 and 703. In the present invention, the "radial direction" which is the direction in which the oil supply holes are formed broadly includes the direction from the oil supply passages 701 and 703 toward the outer surface of the shaft.

〔Effect of the invention〕

As explained above, in the compressor of the present invention, the oil supply passage communicating with the inclined groove and the oil supply hole connecting the oil supply passage and the outer surface of the shaft are formed in the shaft, so that the lubricating oil inside the compressor is The lubricant is smoothly supplied to the lubricated part through the shaft. Therefore, the compressor of the present invention has the excellent effect of ensuring smooth rotational operation.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the compressor of the present invention, FIG. 2 is a cross-sectional view showing a compressor previously proposed by the present inventors, and FIG.
The figure is a sectional view showing a cylinder block of the compressor shown in FIG. 1. DESCRIPTION OF SYMBOLS 1... Shaft, 7... Piston, 10... Swash plate, 30... Spool, 40... Slide part, 80...
··bottle. 105...Slit part, 165...Flat plate part, 166
... Inclined groove, 710, 702 ... Oil supply passage, 703
, 704... Oil supply hole. Representative Patent Attorney Takashi Okabe Figure 3

Claims (1)

[Claims] (1) A cylinder block having a cylinder chamber inside; a shaft rotatably supported within the cylinder block and having a flat plate portion in a part thereof; and a slit into which the flat plate portion of the shaft is fitted;
a swash plate that is swingably connected to the shaft through engagement between the slit and the flat plate portion and rotates integrally with the shaft; and a swash plate that is slidably disposed within the cylinder chamber and that controls the swing movement of the swash plate. a piston that reciprocates within the cylinder chamber in response to the piston; a working chamber that is formed at each end of the piston between the inner surface of the cylinder chamber and that sucks, compresses, and discharges fluid; A support part that swingably supports the swash plate, and a spool that displaces the support part in the axial direction of the shaft, an inclined groove is formed in the flat plate part, and an inclined groove is formed in the slit part. A pin through hole is formed, and the swash plate is swingably connected to the shaft by a pin inserted into the pin through hole and the slanted groove, and one end of the shaft is opened in the slanted groove. A variable capacity swash plate characterized in that an oil supply passage is formed in the axial direction of the shaft, and an oil supply hole is formed in the shaft radial direction, one end communicating with the oil supply passage and the other end opening on the outer surface of the shaft. mold compressor.