WO1999066203A1

WO1999066203A1 - Variable displacement swash plate type clutchless compressor

Info

Publication number: WO1999066203A1
Application number: PCT/JP1999/003203
Authority: WO
Inventors: Yukio Kazahaya; Shoichi Kido
Original assignee: Bosch Automotive Systems Corporation
Priority date: 1998-06-16
Filing date: 1999-06-16
Publication date: 1999-12-23
Also published as: EP1088991A1

Abstract

A variable displacement wash plate type clutchless compressor, wherein, a path (58) is opened by a control valve (81) and a pressure in a crank chamber (8) rises to reduce the inclination of a swash plate (10) when a heat load is reduced, the cross sectional area of a second path (57) is reduced remarkably by the swash plate (10) to suppress a pressure in the crank chamber (8) from lowering when the inclination of the swash plate (10) is reduced to a minimum, whereas a delivery path (39a) is shut off by a check valve (31) when a pressure in the crank chamber (8) rises, and a pressure in the crank chamber (8) is applied to one side of the check valve (31) and a pressure in a delivery chamber (12) is applied to the other side of it because a pressure difference between the crank chamber (8) and the delivery chamber (12) is smaller and stabler than that between a suction chamber (13) and the delivery chamber (12), whereby, when a pressure in the delivery chamber is lowered gradually as a heat load is reduced, a piston stroke becomes minimum and the check valve (31) can be kept open until the swash plate (10) reduces the path area of a first path.

Description

Description Variable-capacity swash plate type clutchless compressor Technical field

The present invention relates to a variable-capacity swash plate type clutchless compressor to which, for example, the driving force of an engine is constantly transmitted, and in particular, to prevent a high-pressure refrigerant from flowing out to a condenser at an extremely low load, thereby allowing the refrigerant to flow inside the compressor. The present invention relates to a variable capacity swash plate type clutchless compressor that circulates and reduces the refrigeration capacity to zero. Background art

There is a variable-capacity swash plate type clutchless compressor as a conventional clutchless compressor. In this clutchless compressor, the inclination angle of the swash plate changes according to the suction pressure, the stroke of the stone changes, and the discharge rate increases or decreases.

When a variable displacement swash plate type clutchless compressor that does not have a minimum discharge capacity of zero is used as the clutchless compressor, the heat load decreases (the compressor with a clutch). The cooling of the evaporator is caused by the refrigerant, the frost forms on the surface of the evaporator, and the evaporator freezes, making it difficult to ventilate. May be impaired.

As a technology to prevent this, there is a technology that circulates the coolant inside the compressor when the heat load is reduced to make the discharge amount zero (Japanese Patent Application Laid-Open No. Hei 7-23080). Gazette).

With this clutchless compressor, the heat load is reduced Note that the inclination angle of the swash plate decreases, and the swash plate pushes the transmission cylinder toward the rear side, and the transmission cylinder pushes the blocking body toward the rear side. When the swash plate is most inclined, the shut-off body closes the suction passage, preventing the inflow of low-pressure refrigerant gas from the evaporator. On the other hand, the control valve communicates the discharge chamber with the crank chamber, and the high-pressure refrigerant gas in the discharge chamber flows to the crank chamber, and the refrigerant gas hardly flows to the capacitor side. In this way, when the inclination angle of the swash plate is at the minimum (at the time of the minimum bistro stroke), most of the refrigerant gas circulates inside the compressor, and the refrigeration capacity can be reduced to zero. Also, since the refrigerant gas circulates internally, the sliding parts are sufficiently lubricated and cooled.

However, since a structure is adopted in which a transmission cylinder and a blocker for closing the suction passage are mounted on the rotating shaft, the discharge chamber must be located outside the suction chamber in the cylinder head. No stricter seal management with outside air. For example, higher processing accuracy and an appropriate tightening amount of the port (bolt for connecting the cylinder block and the head) are required.

In addition, since a structure is used in which a preload is applied to the rotating shaft by a spring via a transmission cylinder, a bearing, and a blocking body, a sufficient preload cannot be applied to the rotating shaft due to its structure. As a result, the rotating shaft and the rotating support are not stabilized in the axial direction, and noise due to vibration increases. In particular, when the load is large under a high load, the spring that urges the breaker is extended, and the noise is further increased.

Furthermore, since the blocking body rotates with the rotation of the rotating shaft, the spring for urging the blocking body rotates together with the blocking body to cut off the thread, so that the suction passage may not be opened or closed. An object of the present invention is to provide a variable-capacity swash plate type clutchless compressor that facilitates management of seals against outside air, suppresses noise, and further improves reliability. And Disclosure of the invention

A variable-capacity swash plate type clutchless compressor according to a first aspect of the present invention is mounted on a rotating shaft so as to be slidable and tiltable, and rotates integrally with the rotating shaft. A crank chamber for accommodating the swash plate, a suction chamber for accommodating a refrigerant gas to be sent to the compression chamber, and a refrigerant gas in the crank chamber guided to the suction chamber, and the inclination angle of the swash plate A first passage whose passage cross-sectional area is reduced by the swash plate when the pressure is minimum, a discharge chamber for accommodating the refrigerant gas discharged from the compression chamber, and a condenser for discharging the refrigerant gas from the discharge chamber. A discharge port for sending refrigerant gas from the discharge chamber to the discharge port; a second path for guiding refrigerant gas from the discharge chamber to the crank chamber; It is installed on the way, and when the heat load increases A pressure control valve that shuts off the second passage at the time of opening, and a pressure control valve that is provided in the middle of the discharge passage, and the pressure of the crank chamber and the urging force of the urging member act in the valve closing direction to move in the valve opening direction. A discharge control valve for shutting off the discharge passage when a pressure difference between the crank chamber and the discharge chamber becomes equal to or less than a predetermined value due to a pressure of the discharge chamber acting on the discharge chamber; A third passage for guiding the refrigerant gas in the crank chamber to the suction chamber only when the passage is shut off. According to the first aspect of the present invention, since there is no need to mount a mechanism for opening and closing the suction port on the rotating shaft, the suction chamber can be arranged outside the discharge chamber in the housing, and a seal with the outside air can be provided. Management becomes easier. In addition, the spring for applying preload to the rotating shaft does not break with the rotation of the rotating shaft and loses its thread, making it impossible to open and close the suction port, improving the reliability of the compressor. You. Furthermore, since sufficient preload can be given to the rotating shaft, the rotating shaft is stabilized in the axial direction, and noise due to vibration can be suppressed.

Further, since the pressure difference between the crank chamber and the discharge chamber is smaller than the pressure difference between the suction chamber and the discharge chamber and is stable, a spring for biasing the check valve body in the valve closing direction is provided. As a result, a spring having a relatively small spring force can be used. As a result, when the pressure in the discharge chamber gradually decreases as the heat load decreases, the check valve (discharge control valve) remains open until the minimum piston stroke (extremely low load) is reached. Can be kept.

Preferably, the discharge control valve is a check valve.

In addition, a first orifice is formed in the middle of the third passage, and a passage area of the first orifice is increased by a second orifice formed in the middle of the first passage. It is preferred that it be smaller than the passage area of the access.

According to this preferred aspect, the function of introducing the refrigerant gas from the crank chamber to the suction chamber through the third passage only when the passage cross-sectional area of the first passage is reduced by the swash plate is simplified. It can be realized with a configuration.

Variable capacity type swash plate type clutchle according to a second aspect of the present invention The compressor is slidably and tiltably mounted on the rotating shaft, and is configured to rotate integrally with the rotating shaft, a crank chamber accommodating the swash plate, and a suction chamber accommodating refrigerant gas to be sent to the compression chamber. A first passage in which the refrigerant gas in the crank chamber is guided to the suction chamber, and a cross-sectional area of the passage is reduced by the swash plate when the inclination angle of the swash plate is minimum; A discharge chamber for containing the refrigerant gas discharged from the compression chamber, a discharge port for sending the refrigerant gas from the discharge chamber to the capacitor side, and a discharge gas for guiding the refrigerant gas of the discharge chamber to the discharge port A passage, a second passage for guiding the refrigerant gas from the discharge chamber to the crank chamber, and a passage provided in the middle of the second passage, wherein the second passage is shut off when the heat load increases. And a pressure control valve on the second passage. A pressure reducing means provided in the flow to reduce the flow of the refrigerant gas guided to the crank chamber; and a pressure of the refrigerant gas downstream of the pressure control valve and upstream of the pressure reducing means, and an urging force of an urging member. Acts in the valve closing direction, and the pressure in the discharge chamber acts in the valve opening direction, so that the pressure of the refrigerant gas downstream of the pressure control valve and upstream of the pressure reducing means and the discharge pressure A discharge control valve that shuts off the discharge passage when the pressure difference in the room becomes equal to or less than a predetermined value; and a refrigerant gas in the crank chamber only when the discharge control valve shuts off the discharge passage. A third passage leading to the suction chamber.

According to the second aspect of the present invention, since the refrigerant gas in the discharge chamber is directly introduced into the discharge control valve to drive the discharge control valve, the response of the discharge control valve is improved, and the discharge control valve can be quickly operated. The amount of refrigerant discharged (the capacity of the compressor) can be changed, and cooling filling is improved. Also, for example, even under high load, high rotation, and other operating conditions where the pressure in the crank chamber cannot rise quickly as the pressure in the discharge chamber rises, the discharge control valve operates reliably and the refrigeration capacity can be reduced to zero. Therefore, in order to ensure the operation of the discharge control valve, it is not necessary to set the passage cross-sectional area of the first passage small and set the pressure in the crank chamber high. Therefore, the damage to the components in the crank chamber is reduced, and the durability and reliability of the compressor are improved.

Preferably, the pressure reducing means is a third orifice located downstream of the pressure control valve.

According to this preferred aspect, when the second passage is opened, the flow rate of the refrigerant gas is reduced by the third orifice, the pressure of the refrigerant gas supplied to the crank chamber is reduced, and Link chamber pressure is not too high.

Further, a fourth orifice is provided in the middle of a fourth passage for guiding refrigerant gas downstream of the pressure control valve and upstream of the pressure reducing means to the discharge control valve, and the third orifice is provided. It is preferable that the cross-sectional area of the passage of the wheel is smaller than the cross-sectional area of the passage of the fourth orifice.

According to this preferred aspect, when the second passage is opened, the flow rate of the refrigerant gas in the fourth passage is reduced by the fourth orifice, and the refrigerant gas in the discharge chamber flows into the discharge control valve. Since the shock applied to the discharge control valve at that time is reduced, the damage received by the discharge control valve is reduced, and the durability and reliability are improved.

Further, it is preferable that a part of the first passage is constituted by a hole formed in an annular body fixed to the rotating shaft. No.

According to this preferred aspect, the swash plate comes into contact with the annular body when the inclination angle of the swash plate is minimized, but the annular body rotates integrally with the swash plate, so that the swash plate is fixed to the housing or the housing. The swash plate wear is suppressed as compared with the case where a structure that makes contact with the annular body is adopted.

Further, the third passage includes a front-side bearing accommodating space for accommodating a shaft seal and a front-side bearing on the front side of the rotating shaft, and the crank chamber. A front-side passage communicating with the front shaft, a rear-side bearing accommodating space provided in the rotary shaft for housing a rear-side bearing on the rear side of the rotary shaft, and a front-side passage. It is preferable that it is constituted by a rotary shaft side passage for communicating with the bearing housing space and a rear side passage for communicating the above-mentioned bearing housing space with the above-mentioned suction chamber.

According to this preferable aspect, even when the inclination angle of the swash plate is minimized, each bearing and the shaft seal are lubricated and cooled by the lubricating oil in the refrigerant gas passing through the third passage, and seizure occurs. Can be prevented. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a vertical sectional view showing a state in which a discharge passage of a variable displacement type swash plate type clutchless compressor according to an embodiment of the present invention is open.

FIG. 2 is a partially enlarged view showing a state where the discharge passage is opened. FIG. 3 is a longitudinal sectional view showing a state in which a discharge passage of a variable displacement type swash plate type clutchless compressor according to an embodiment of the present invention is closed. FIG.

FIG. 4 is a partially enlarged view showing a state where the discharge passage is closed. FIG. 5 is a longitudinal sectional view showing a state in which a discharge passage of a variable displacement type swash plate type clutchless compressor according to another embodiment of the present invention is closed.

FIG. 6 is a partially enlarged view of a rear head of the variable displacement type swash plate type clutchless compressor shown in FIG. 5, showing a state in which a discharge passage is closed.

FIG. 7 is a partially enlarged view of a rear head of the variable displacement type swash plate type clutchless compressor of FIG. 5, showing a state in which a discharge passage is opened.

FIG. 8 is an enlarged cross-sectional view showing different cross-sections of a rear head of the variable-capacity swash plate type clutchless compressor of FIG. 5, and is a view showing a fourth passage. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a state in which a discharge passage of a variable displacement type swash plate type clutchless compressor according to an embodiment of the present invention is open, FIG. 2 is a partially enlarged view thereof, and FIG. Is a longitudinal sectional view showing a closed state, and FIG. 4 is a partially enlarged view of FIG.

One end of the cylinder block 1 of this variable capacity swash plate type clutchless compressor has a lid head 3 via a valve plate 2 and the other end has a front head 4 Are fixed respectively. The cylinder block 1 has a plurality of cylinder bores 6 at predetermined intervals in the circumferential direction around a shaft (rotation axis) 5. It is arranged. A piston 7 is slidably accommodated in each of the cylinder pores 6.

A crank chamber 8 is formed in the front head 4, and a swash plate 10 is accommodated in the crank chamber 8. The sliding surface 10a of the swash plate 10 holds the spherical end 11a of the connecting groove 11a on the sliding surface 10a. Have been. The retainer 53 is mounted on the boss 10b of the swash plate 10 via a radial bearing 55, and the retainer 53 is rotatable relative to the swash plate 10. The radial bearing 55 is prevented from coming off by a flange 54 fixed to the boss 10b with a screw 45. The other end 1 lb of the connecting groove 11 is fixed to the piston 7.

The shroud 50 is composed of a housing body 51 that supports the tip end surface of the connecting groove 11a so as to be relatively rotatable, and the one end 11a of the connecting groove 11a. It consists of a washer 52 that supports the rear end face so that it can roll relatively.

A discharge chamber 12 and a suction chamber 13 are formed in the lid 3. The suction chamber 13 is arranged so as to surround the discharge chamber 12. Riahead 3 is provided with an inlet (not shown) that leads to the outlet of the evaporator (not shown).

FIG. 2 is an enlarged longitudinal sectional view showing a state where the discharge passage 39 is open, and FIG. 4 is an enlarged longitudinal sectional view showing a state where the discharge passage 39 is closed.

A check valve (discharge control valve) 31 is provided in the middle of the discharge passage 39 that connects the discharge chamber 12 and the discharge port 1a. The discharge passage 39 has a passage 39 a formed in the lid 3 and a discharge passage 39 a. And a passage 39b formed in the lube plate 2. The passage 39 b leads to a discharge port 1 a formed in the cylinder block 1.

A spring (biasing member) 32 is housed in the bottomed cylindrical check valve 31, and a stopper 56 fixed to the lid 3 with a cap 59 is provided in a stopper 56. One end of the spring 32 is in contact, and the other end of the spring 32 is in contact with the bottom of the check valve 31. The internal space 33 of the check valve 31 communicates with the crank chamber 8 via a passage 34.

On one side (upper side) of the check valve 31, the urging force of the spring 32 and the pressure of the crank chamber 8 act in the valve closing direction (the direction in which the valve opening decreases). When the check valve 31 is opened, the discharge port la and the discharge chamber 12 communicate with each other through the discharge passage 39 (see FIG. 2). Therefore, on the other side (lower side) of the check valve 31, the pressure of the discharge port 1 a and the pressure of the discharge chamber 12 act in the valve opening direction (the direction in which the valve opening increases). However, when the pressure difference between the crank chamber 8 and the discharge port la becomes less than a predetermined value, the check valve 31 moves in the closing direction, the discharge passage 39 is shut off, and the check valve 3 is closed. On the lower side of 1, only the pressure of the discharge chamber 12 acts in the valve opening direction. That is, the pressure of the discharge port 1 a does not act on the lower side of the check valve 31.

The discharge chamber 12 and the crank chamber 8 communicate with each other via a second passage 57. A control valve (pressure control valve) 81 is provided in the middle of the passage 57. When the thermal load is large, the valve body 81b is seated by energizing the solenoid (not shown) of the control port 81, and the second passage 57 is shut off. When the load is small, the valve body 81b is closed by stopping power supply to the solenoid. The second passageway 57 is opened away from it. The operation of the control valve 81 is controlled by a computer (not shown).

The suction chamber 13 and the crank chamber 8 communicate with each other via a first passage 58. The first passage 58 has an orifice (second orifice) 58 a formed in the valve plate 2 and a passage 58 b formed in the cylinder opening 1. And a hole 58 c formed in a ring (annular body) 59 fixed to the shaft 5. The suction chamber 13 and the crank chamber 8 communicate with each other via a third passage 60. The third passage 60 includes a passage 60 a formed in the front head 4, a front bearing housing space 60 b formed in the front head 4, A passage 60 c formed in the shaft 5, a rear-side bearing accommodating space 60 d formed in the cylinder block 1, a passage 58 b of the cylinder block 1, and a valve plate 2 orifice 58a. The passage 58b of the cylinder block 1 and the orifice 58a of the valve plate 2 form a part of the first passage 58 and the passage 58b of the third passage 60. Make up part. An internal thread 61 is formed on the inner peripheral surface of the rear end of the passage 60c, and a screw -62 is screwed into the internal thread 61. An orifice (first orifice) 62 a is formed in the screw 62, and the passage area of the orifice 62 a forms a part of the first passage 58. Smaller than the passage area of the orifice 58a of the valve plate 2. Therefore, the third passage is provided only when the boss portion 10b of the swash plate 10 almost blocks the hole 58c of the ring 59 and the passage cross-sectional area of the first passage 58 is greatly reduced. The refrigerant gas in the crank chamber 8 is led to the suction chamber 13 through 60. W

The valve plate 2 has a discharge port 16 for communicating the compression chamber 82 with the discharge chamber 12 and a suction port 15 for communicating the compression chamber with the suction chamber 13 in the circumferential direction. Are provided at predetermined intervals. The discharge port 16 is opened and closed by a discharge valve 17, and the discharge valve 17 is connected to a bolt 19 and a nut 20 together with a valve retainer 18 on the rear end face of the valve plate 2. More fixed. The suction port 15 is opened and closed by a suction valve 21, and the suction valve 21 is disposed between the valve plate 2 and the cylinder block 1.

Shaft 5 is provided by radial bearings (Rear bearings) 24 and thrust bearings (Lear bearings) 25 housed in the rear bearing housing space 60 d of cylinder block 1. The radial end (front side bearing) of the front head 4 is rotatably supported, and the radial bearing (front side bearing) 26 accommodated in the front side bearing housing space 60 b of the front head 4. Thus, the front end of the shaft 5 is rotatably supported. In addition to the radial bearing 26, a shaft seal 46 is housed in the bearing housing space 60 b on the front side.

A female screw 1 b is provided at the center of the cylinder block 1, and an Asian nut 83 is screwed to the female screw 1 b. By tightening the adjust nut 83, a preload is applied to the shaft 5 via the thrust bearing 25. A pulley (not shown) is fixed to the front end of the shaft 5.

A thrust flange 40 for transmitting the rotation of the shaft 5 to the swash plate 10 is fixed to the shaft 5, and the thrust flange 40 is a thrust bearing 33. Through the inner wall of the front head 4 W

Supported on the surface. The thrust flange 40 and the swash plate 10 are connected via a hinge mechanism 41, and the swash plate 10 can be inclined with respect to an imaginary plane perpendicular to the shaft 5.

The swash plate 10 is slidably and tiltably mounted on the shaft 5.

The hinge mechanism 41 includes a bracket 1 Oe provided on the front surface 10 c of the swash plate 10 and a linear guide groove 10 provided on the bracket 10 e. f, and a rod 43 screwed to the swash plate side end face 40a of the thrust flange 40. The longitudinal axis of the guide groove 10 f is inclined by a predetermined angle with respect to the front surface 10 c of the swash plate 10. The spherical portion 43a of the rod 43 is fitted into the guide groove 10f so as to be relatively slidable.

Next, the operation of the variable capacity type swash plate type clutchless compressor will be described.

The rotational power of the vehicle-mounted engine is constantly transmitted to a pulley (not shown) and a shaft 5 via a belt (not shown), and the rotating power of the shaft 5 is a thrust flange 40 and a hinge mechanism 41. Is transmitted to the swash plate 10 through the rotation of the swash plate 10.

The rotation of the swash plate 10 causes the shower 50 to relatively rotate on the rear surface 10a of the swash plate 10, so that the rotation force from the swash plate 10 causes the linear reciprocating motion of the piston 7 Is converted to The piston 7 reciprocates in the cylinder bore 6, and as a result, the volume of the compression chamber 82 in the cylinder bore 6 changes. This change in volume causes the suction, compression and discharge of the refrigerant gas to be performed sequentially. The refrigerant gas having a capacity corresponding to the inclination angle of the swash plate 10 is discharged. During suction, the suction valve 21 opens, and low-pressure refrigerant flows from the suction chamber 13 to the compression chamber 82 in the cylinder bore 6. W

At the time of suction and discharge, the discharge valve 17 is opened, and high-pressure refrigerant gas is discharged from the compression chamber 82 to the discharge chamber 12.

When the heat load decreases (when the clutch compressor has a clutch-off equivalent), the power supply to the solenoid of the control valve 81 is stopped and the plunger 8Id opens. , The valve element 81b moves in the valve opening direction against the urging force of the spring 81c, and the second passage 57 opens. As a result, high-pressure refrigerant gas flows out of the discharge chamber 12 to the crank chamber 8 through the second passage 57, and the pressure in the crank chamber 8 increases, and the swash plate 10 tilts. The angle becomes smaller. When the inclination angle of the swash plate 10 is minimized, the boss 10 b of the swash plate 10 almost closes the hole 58 c of the ring 59, and the cross-sectional area of the first passage 58 is reduced. Since the pressure is largely reduced, the pressure drop in the crank chamber 8 is suppressed.

When the pressure difference between the discharge chamber 12 and the crank chamber 8 falls below the predetermined value P, the pressure between the pressure of the crank chamber 8 acting on the upper side of the check valve 31 and the urging force of the spring 32 is increased. When the resultant force overcomes the pressure of the refrigerant gas in the discharge chamber 12 acting on the lower side of the check valve 31, the check valve 31 moves in the valve closing direction to shut off the discharge passage 39 ( (See Fig. 4). As a result, the outflow of the refrigerant gas from the discharge port 1a to the capacitor 84 is prevented. At this time, as described above, the post section 10b of the swash plate 10 substantially closes the hole 58c of the ring 59, and the cross-sectional area of the first passage 58 is greatly reduced. The refrigerant gas in the crank chamber 8 flows to the suction chamber 13 through the passage 60 of 3. This suppresses an excessive rise in the pressure of the crank chamber 8 and enables the refrigerant gas to circulate in the compressor.

At the time of minimum bistro stroke (as shown in Fig. 3), refrigerant gas is absorbed. It returns to the suction chamber 13 through the entrance chamber 13, the compression chamber 82, the discharge chamber 12, the second passage 57, the crank chamber 8, and the third passage 60 in this order.

In addition, the refrigerant gas in the crank chamber 8 flows from the passage 60 a of the front head 4 to the front-side bearing housing space 60 b, the passage 60 c of the shaft 5, The air flows into the suction chamber 13 through the bearing housing space 60 d, the passage 58 b of the cylinder block 1, and the orifice 60 f of the valve plate 2. At this time, the refrigerant gas is throttled by the orifice 62 a of the screw 62 in the middle of the passage 60 c of the shaft 5, and then is re-cooled by the orifice 58 a of the knob plate 2. And the pressure decreases.

In this embodiment, the pressure of the crank chamber 8 is applied to one of the check valves 31 as a discharge control valve, and the pressure of the discharge chamber 12 is applied to the other of the check valves 31. A relatively small spring force is used as the spring 32 that urges the check valve 31 in the valve closing direction, so that the heat load is reduced and discharge is performed. When the pressure in the chamber 12 gradually decreases, the minimum piston stroke (extremely low load) is reached, and the check valve 3 is used until the swash plate 10 reduces the passage area of the first passage 58. 0 is kept open.

On the other hand, when the heat load increases, the plunger 81 d moves in the valve closing direction due to the energization of the solenoid of the control valve 81, and the valve element 81b moves the spring. 8 1c moves in the valve closing direction by the biasing force, and the second passage 57 is closed. As a result, the flow of high-pressure refrigerant gas from the discharge chamber 12 to the crank chamber 8 is prevented, the pressure in the crank chamber 8 decreases, and the inclination angle of the swash plate 10 increases. It becomes bad. When the inclination angle of the swash plate 10 is changed from the minimum to the maximum, the boss 1 Ob of the swash plate 10 is separated from the hole 58 c of the ring 59 and the first passage 58 is fully opened. Since the refrigerant gas in the crank chamber 8 flows to the suction chamber 13 through the first passage 58, the pressure in the crank chamber 8 is reduced. When the passage area of the first passage 58 is maximized, the refrigerant gas hardly flows from the third passage 60 to the suction chamber 13.

When the pressure in the discharge chamber 12 increases and the pressure difference between the discharge chamber 12 and the crank chamber 8 exceeds a predetermined value P, the pressure in the discharge chamber 12 acting on the check valve 31 increases. The pressure of the refrigerant gas overcomes the resultant force of the pressure of the refrigerant gas in the crank chamber 8 and the urging force of the spring 32, the spool valve 31 moves in the valve opening direction, and the discharge passage 39 opens. See Figure 2). As a result, the refrigerant gas in the discharge chamber 12 flows out from the discharge port 1a to the capacitor 84.

The variable-capacity swash plate type clutchless compressor of this embodiment has the following effects.

Since there is no need to install a mechanism that opens and closes the suction port in the shaft 5 (conventional transmission cylinder, blocking body, etc.), the suction chamber 13 is located outside the discharge chamber 12 inside the rear head 3. They can be placed, making it easier to manage seals with the outside air. Furthermore, since the spring for giving the pre-opening to the shaft 5 does not cut off as the shaft 5 rotates and the inlet 3a cannot be opened and closed, the reliability of the compressor is improved. improves.

The adjust nut 8 3 can be tightened to provide a sufficient pre-opening to the shaft 5, so that the shaft 5 and the thrust flange 40 are stabilized in the axial direction and the vibration Control noise I can do it.

Since the structure of the cylinder block 1 etc. is not complicated, parts can be shared with the variable capacity swash plate type compressor with a clutch.

Since the check valve 31 is employed as the discharge control valve, the configuration can be simplified.

When the inclination angle of the swash plate 10 becomes minimum, the ring 59 that comes into contact with the swash plate 10 rotates together with the swash plate 10, so that the swash plate 10 is directly or in contact with the cylinder block 1. Compared to contact with the ring fixed to the cylinder block 1, wear of the swash plate 10 is suppressed.

In this embodiment, the pressure difference between the crank chamber 8 and the discharge chamber 12 is smaller than the pressure difference between the suction chamber 13 and the discharge chamber 12 and the pressure in the crank chamber 8 is Focusing on the fact that the pressure does not change significantly due to load fluctuations compared to the pressure of the valve, the pressure of the crank chamber 8 acts on one of the spool valves 31 as a discharge control valve, and the other of the check valves 31 Since the structure for applying the pressure of the discharge chamber 12 was adopted, a relatively small spring force could be used as the spring 32 for biasing the check valve 31 in the valve closing direction. As a result, when the pressure in the discharge chamber 12 gradually decreases as the heat load decreases, the check valve 31 is kept open until the minimum piston stroke (extremely low load) is achieved. Can be kept.

Incidentally, a variable displacement swash plate type clutchless compressor having a structure in which the pressure of the suction chamber acts on one of the check valves as the discharge control valve and the pressure of the discharge chamber acts on the other of the check valves. Since the pressure difference between the suction chamber and the discharge chamber is large in A spring with a relatively large spring force must be used as a spring that biases in the valve closing direction. In addition, the pressure in the suction chamber changes greatly due to load fluctuations. As a result, when the pressure in the discharge chamber gradually decreases as the heat load decreases, the check valve operates before the minimum piston stroke occurs, the discharge passage is shut off, and refrigerant gas is released. It may not flow out from the discharge port to the capacitor side. According to this embodiment, such a problem is solved.

Since a part of the fourth passage 60 is constituted by the front-side bearing housing space 60 and the rear-side bearing housing space 60d, the lubricating oil of the refrigerant gas passing through the third passage 60 is used. The bearings 26, 24, 25 and the shaft seal 46 are lubricated and cooled.

In the above-described embodiment, the case where the check valve 31 is used as the discharge control valve is described. However, a valve other than the check valve such as the spool valve or the one-way valve may be used. Good.

FIG. 5 is a longitudinal sectional view showing a state in which a discharge passage of a variable capacity type swash plate type clutchless compressor according to another embodiment of the present invention is closed, and FIG. 6 is a variable capacity type shown in FIG. FIG. 7 is a partially enlarged view of a swash plate type clutchless compressor, showing a state in which a discharge passage is closed. FIG. 7 is a rear head of the variable displacement type swash plate type clutchless compressor shown in FIG. Fig. 8 is an enlarged cross-sectional view showing a different cross section of the rear head of the variable capacity swash plate type clutchless compressor shown in Fig. 5; FIG. 14 is a diagram showing a fourth passage.

In the above-described embodiment, the refrigerant gas in the crank chamber 8 is guided to one of the check valves 31 as a pressure control valve, and the pressure control valve is closed. Then, as described later, Refrigerant gas in the discharge chamber 112 was directly introduced to one of the check valves 133 as a control valve, and the pressure control valve was closed.

This embodiment will be described below with reference to FIGS. However, portions common to the above-described embodiments are denoted by the same reference numerals in the drawings, and description thereof will be omitted.

A check valve 13 1 is provided in the middle of the discharge passage 13 9 that connects the discharge chamber 1 12 and the discharge port la. The discharge passage 139 is constituted by a passage 139 a formed in the head 103 and a passage 39 formed in the knob plate 2. The passage 139 b leads to a discharge port 1 a formed in the cylinder block 1.

A spring (biasing member) 13 2 is housed in the bottomed check valve 13 1, and one end of the spring 13 2 abuts the annular holder 56, and the other end of the spring 3 2 Check valve 31 is in contact with the bottom surface. A cap 15 9 is fixed to the lid 10 3, and the annular holder 56 is pressed against the cap 15 9 by the biasing force of the spring 13 2. The internal space 133 of the check valve 13 1 communicates with the crank chamber 8 via the passage 13 4.

One side (upper side) of the check valve 13 1 has the urging force of the spring (biasing member) 13 2 and the pressure of the refrigerant gas guided through the fourth passage 71 1 in the valve closing direction (valve opening direction). In the direction of decreasing degree). When the check valve 13 1 is opened, the discharge port 1 a communicates with the discharge chamber 1 12 via the discharge passage 1 39. Therefore, on the other side (lower side) of the check valve 131, the pressure of the discharge port la and the pressure of the discharge chamber 112 act in the valve opening direction (the direction in which the valve opening increases). However, the pressure difference between one of the check valves 13 1 and the other is When the pressure falls below the predetermined value, the check valve 13 1 moves in the valve closing direction to block the discharge passage 13 9, and the discharge chamber 1 12 is located below the check valve 13 1. Only pressure acts in the valve opening direction. In other words, the pressure of the discharge port 1 a does not work below the check valve 13 1.

The discharge chamber 112 and the crank chamber 8 communicate with each other via the second passage 157. A control valve (pressure control valve) 81 is provided in the middle of passage 157. An orifice (third orifice) 70 is provided on the second passageway 15 7 and downstream of the control valve 81 as pressure reducing means. The pressure of the refrigerant gas guided from the discharge chamber 112 to the crank chamber 8 is reduced by the heat 70. When the heat load is large, the valve body 81 is seated by energizing the solenoid (not shown) of the control valve 81, and the second passage 157 is shut off. When is smaller, the valve body 8 lb is separated from the valve seat and the second passage 157 is opened by stopping the power supply to the solenoid. The operation of the control valve 81 is controlled by a computer (not shown). The section 157a on the second passageway 157 and between the downstream of the control valve 81 and the upstream of the orifice 70 and the interior of the check valve 131 The space 13 3 communicates with the space 13 via a fourth passage 71 formed in the head 103. In the middle of the fourth passage 71, an orifice (fourth orifice) 72 is mounted. The flow rate of the refrigerant gas guided from the fourth passage 71 to the internal space 13 3 of the check valve 13 1 is reduced by the orifice 72. The passage cross-sectional area of the first orifice 70 is smaller than the passage cross-sectional area of the orifice 72. The first passage 158 includes a passage 158 a formed in the valve plate 2, a passage 58 b formed in the cylinder block 1, and a ring fixed to the shaft 5. And a hole 58c formed in 59. This embodiment differs from the embodiment shown in FIG. 1 in that the passage 158a formed in the valve plate 2 is not an orifice. The third passage 60 includes a passage 60 a formed in the front head 4, a front bearing housing space 60 b formed in the front head 4, The passage 60 c formed in the foot 5, the rear bearing housing space 60 d formed in the cylinder block 1, the passage 58 b of the cylinder block 1, and the valve plate 2 It is composed of 158 a. The passage 58b of the cylinder block 1 and the passage 158a of the valve plate 2 constitute a part of the first passage 58 and a part of the third passage 60. Make up the part.

When the heat load is reduced, the power supply to the solenoid of the control valve 81 is stopped, the plunger 81 d moves in the valve opening direction, and the valve body 81b is moved to the spring 81. The valve moves in the valve opening direction against the urging force of c, and the second passage 157 opens. As a result, high-pressure refrigerant gas flows from the discharge chamber 112 to the crank chamber 8 via the second passage 157. At this time, the flow rate of the refrigerant gas sent to the crank chamber 8 is limited by the orifice 70, and the pressure thereof also decreases. Due to the high-pressure refrigerant gas from the discharge chambers 11 and 12, the internal pressure of the crank chamber 8 gradually increases, and the inclination angle of the swash plate 10 decreases. When the inclination angle of the swash plate 10 becomes minimum, the boss 10 b of the swash plate 10 almost closes the hole 58 c of the ring 59, and the cross-sectional area of the first passage 58 is large. Pressure in the crank chamber 8 The bottom is suppressed. The high-pressure refrigerant gas downstream of the control valve 81 and upstream of the orifice 70 passes through the fourth passage 71 to the internal space 13 3 of the check valve 13 1. Sent to The discharge acting on the lower side of the check valve 13 1 is the sum of the pressure acting on the upper side of the check valve 13 1 (the pressure in the internal space 13 3) and the biasing force of the spring 13 2. When the pressure in the chamber 1 12 is overcome, the check valve 13 1 moves in the valve closing direction and the discharge passage 13 9 is shut off (see FIG. 6). As a result, the outflow of the refrigerant gas from the discharge port 1a to the capacitor 84 is prevented. At this time, as described above, the boss portion 10b of the swash plate 10 almost closes the hole 58c of the ring 59 and the passage cross-sectional area of the first passage 58 is greatly reduced. The refrigerant gas in the crank chamber 8 flows into the suction chamber 13 through the passage 60. This suppresses an excessive rise in the pressure of the crank chamber 8 and allows the refrigerant gas to circulate in the compressor.

At the time of the minimum piston stroke (as shown in Fig. 5), the refrigerant gas enters the suction chamber 113, the compression chamber 82, the discharge chamber 112, the second passage 157, and the crank chamber 8. And the third passage 60 sequentially returns to the suction chamber 113 again.

On the other hand, when the heat load increases, the control valve 81 closes, and the second passage 157 closes. As a result, the inflow of high-pressure refrigerant gas from the discharge chamber 111 to the crank chamber 8 is prevented, the pressure in the crank chamber 8 gradually decreases, and the inclination angle of the swash plate 10 increases. It becomes bad. Further, the pressure of the refrigerant gas guided to the internal space 133 of the check valve 13 1 through the fourth passage 71 also decreases.

When the pressure in the discharge chamber 1 1 2 rises, the pressure in the discharge chamber 1 1 2 When the difference between the pressure and the pressure in the internal space 133 of the check valve 13 1 becomes equal to or less than a predetermined value, the pressure of the refrigerant gas in the discharge chamber 112 acting on the check valve 131 is checked. Check valve 13 1 1 overcomes the resultant force of the pressure of the refrigerant gas in the internal space 13 3 of the check valve 13 1 and the urging force of the spring 13 2, and the check valve 13 1 moves in the valve opening direction, and the discharge passage 13 9 Opens (see Fig. 7). As a result, the refrigerant gas in the discharge chamber 112 flows out of the discharge port 1a to the capacitor 84 side.

The variable-capacity swash plate type clutchless compressor according to this embodiment has the same effects as the above-described embodiment, and also has the following effects.

The check valve 13 1 was driven by directly introducing the refrigerant gas from the discharge chamber 1 12 into one of the check valves 13 1 (internal space 13 3). 13 1 responsiveness is improved. As a result, the amount of refrigerant discharged (the capacity of the compressor) can be changed quickly, and cooling filling is improved.

In addition, the check valve 13 1 operates reliably even under operating conditions such as high load and high rotation, for example, when the pressure in the crank chamber 8 cannot increase quickly as the pressure in the discharge chamber 112 increases. Since the refrigerating capacity can be reduced to zero, in order to ensure the operation of the check valve 131, the passage cross-sectional area of the first communication passage 58 is reduced and the crank chamber is reduced. There is no need to set the pressure of 8 higher. Therefore, damage to parts such as the retainer 53 pulling the piston 7 in the crank chamber 8 and the shaft seal 46 that shuts off the crank chamber 8 from the atmosphere is not affected. It becomes smaller, and the durability and reliability of the compressor are improved.

Further, an orifice 72 is provided in the middle of the fourth passage 71. W

Therefore, when the control valve 81 is opened and high-pressure refrigerant gas is sent to the internal space 13 3 of the check valve 13 1, the flow rate of the refrigerant gas at the orifice 72 is reduced. Since the throttle valve is throttled, the impact of the refrigerant gas acting on the check valve 13 1 is reduced.

Also, during the internal circulation of the refrigerant gas, a part of the refrigerant gas in the passage 60c flows through the orifice 60e to the bearing accommodating chamber 60d. 4 and 25 are lubricated and cooled.

In this embodiment, one passage 71 is provided as the fourth passage, but a plurality of passages may be provided. In addition, although one orifice (orifice 70) is installed as a depressurizing means, a plurality of orifices may be installed or an orifice may be used as another depressurizing means. Instead of mounting the face 70, the passage cross-sectional area in the middle of the second passage 157 may be reduced.

In this embodiment, the check valve 13 1 is used as the discharge control valve. However, instead of the check valve 13 1, a spool valve or a port valve (not shown) or the like is used. May be used. Industrial applicability

The variable-capacity swash plate type clutchless compressor according to the present invention is suitable as a refrigerant compressor of a vehicle air conditioner.

Claims

The scope of the claims

1. a swash plate that is slidably and tiltably mounted on the rotating shaft and that rotates integrally with the rotating shaft;

A crank room to accommodate this swash plate,

A suction chamber containing a refrigerant gas to be sent to the compression chamber,

A first passage that guides the refrigerant gas in the crank chamber to the suction chamber, and further reduces a passage cross-sectional area by the swash plate when the inclination angle of the swash plate is minimum;

A discharge chamber for containing the refrigerant gas discharged from the compression chamber, and a discharge for sending the refrigerant gas from the discharge chamber to the capacitor side

P and

A discharge passage for guiding the refrigerant gas in the discharge chamber to the discharge port; and a second passage for guiding the refrigerant gas in the discharge chamber to the crank chamber.

A pressure control valve that is provided in the middle of the second passage and that shuts off the second passage when a thermal load increases;

It is provided in the middle of the discharge passage, and the pressure of the crank chamber and the urging force of the urging member act in the valve closing direction, and the pressure of the discharge chamber acts in the valve opening direction. When,

A discharge control valve that shuts off the discharge passage when a pressure difference between the discharge chamber and the discharge chamber becomes a predetermined value or less;

A third passage for guiding the refrigerant gas in the crank chamber to the suction chamber only when the discharge control valve shuts off the discharge passage;

A variable displacement type swash plate type clutch less press characterized by having:

2. The capacity-type swash plate type clutchless compressor according to claim 1, wherein the discharge control valve is a check valve.

3. A first orifice is formed in the middle of the third passage, and a passage area of the first orifice is increased by a second orifice formed in the middle of the first passage. 3. The variable-capacity swash plate type clutchless compressor according to claim 1 or 2, wherein the area is smaller than a passage area of the swash plate.

4. a swash plate that is slidably and tiltably mounted on the rotating shaft and that rotates integrally with the rotating shaft;

A crank room to accommodate this swash plate,

A first passage that guides the refrigerant gas in the crank chamber to the suction chamber, and further reduces the cross-sectional area of the passage by the swash plate when the inclination angle of the swash plate is minimum;

□ and

A pressure control valve that is provided in the middle of the second passage and that shuts off the second passage when the heat load increases;

A pressure reducing means provided on the second passage downstream of the pressure control valve and for restricting a flow of the refrigerant gas led to the crank chamber; downstream of the pressure control valve and upstream of the pressure reducing means Refrigerant While the gas pressure and the urging force of the urging member act in the valve closing direction, the pressure in the discharge chamber acts in the valve opening direction, and is downstream of the pressure control valve and upstream of the pressure reducing means. A discharge control valve that shuts off the discharge passage when a difference between the pressure of the refrigerant gas and the pressure in the discharge chamber becomes equal to or less than a predetermined value;

A variable displacement swash plate type clutch repressor characterized by having:

5. The variable displacement swash plate type clutchless compressor according to claim 4, wherein the pressure reducing means is a first orifice arranged downstream of the pressure control valve. Ssa.

6. A fourth orifice is provided downstream of the pressure control valve and upstream of the decompression means to guide the refrigerant gas to the discharge control valve, and a fourth orifice is provided in the middle of the fourth orifice. 6. The variable displacement swash plate type clutch press according to claim 5, wherein a cross-sectional area of the passage is smaller than a cross-sectional area of the passage of the fourth orifice. Ssa.

7. A method according to any one of claims 1 to 6, wherein a part of the first passage is constituted by a hole formed in an annular body fixed to the rotating shaft. The variable-capacity swash plate type clutchless compressor described in the section.

8. The third passage includes a front-side bearing receiving space for housing a shaft seal and a front-side bearing on the front side of the rotary shaft; A front-side passage for communicating with the chamber; and A rotary shaft-side passage communicating the rear-side bearing accommodation space for accommodating the bearing, the front-side bearing accommodation space, and a lear-side passage communicating the Lear-side bearing accommodation space with the suction chamber; The variable displacement swash plate type clutchless compressor according to any one of claims 1 to 7, characterized in that: