JPH06213166A - Compressor - Google Patents

Abstract

PURPOSE:To prevent a load fluctuation shock by opening or closing a bleed passage connecting a clutch chamber and an intake chamber interlockingly with an electromagnetic clutch driving a rotary swash plate, and feeding a high-pressure fluid from a delivery chamber to a crank chamber via a throttle passage until a compressor is completely stopped. CONSTITUTION:A drive shaft 7 is connected to an electromagnetic clutch 6 and extended into a crank chamber 5, a rotary swash plate 11 is rotated in the crank chamber 5, a piston 16 is directly moved in a bore 15, and a fluid is sucked into an intake chamber 3a from the crank chamber 5 via a bleed passage 40 and compressed. A switching valve 20 opened or closed by the magnetic action of the electromagnetic clutch 6 is provided on the stator 63 of the electromagnetic clutch 6 to open or close the flow of the bleed passage 40. A delivery chamber 3b delivering the fluid compressed in the bore 15 is communicated with the crank chamber 5 via a throttle passage 41.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor provided with a rotary swash plate capable of tilt displacement.

[0002]

2. Description of the Related Art In order to control the discharge capacity of a compressor used for air conditioning of a vehicle or the like, the pressure applied to the back of the piston is adjusted by the pressure difference between the suction chamber pressure and the crank chamber pressure to adjust the tilt angle of the rotating swash plate. Changing is described in US Pat. No. 386182.
No. 9 and the like. This technology uses blow-by gas as a pressurizing means for adjusting the crank chamber pressure, but as an improved technology that points out the instability of the blow-by gas amount, the cylinder block communicates the discharge chamber and the crank chamber. It is also possible to provide a through hole with a diaphragm function.
It is disclosed in Japanese Patent Publication No. 142277.

Further, in the variable displacement compressor, the inclination angle of the rotating swash plate when the compressor is stopped differs depending on the pressure difference of the working fluid acting before and after the piston, and the inclination angle of the rotating swash plate when the compressor is stopped is large. When the compressor is restarted, the piston starts operating with a stroke according to the tilt angle of the rotating swash plate, so the starting power becomes large, which causes a load fluctuation shock and deteriorates the power performance and driving feeling. There is. The invention disclosed in Japanese Utility Model Laid-Open No. 64-15776 discloses a method for eliminating such a starting shock.
A control valve operable to actuate the high-pressure side working fluid on the rear surface of the piston, and a drive means for actuating the control valve,
There is provided control means for operating the drive means in response to an off signal of the compressor.

[0004]

However, the control valve used in the above invention has a very complicated structure, and as a matter of course, the drive means (solenoid) and the control means inevitably have an extremely high cost. A first problem to be solved by the present invention is to eliminate a starting shock with a simple structure without using expensive components such as a dedicated solenoid valve, and a second problem to be solved is a simple control valve. It is to combine the mechanism to eliminate the starting shock and at the same time have the original capacity changing function.

[0005]

In order to solve the above-mentioned problems, the first invention is directed to a drive shaft which is connected to an electromagnetic clutch and extends into the crank chamber, and a drive shaft which rotates together with the drive shaft in the crank chamber and which is in the crank chamber. A rotary swash plate capable of tilt displacement according to pressure, a piston that is linked to the rotary swash plate and linearly moves in each bore based on its rotational oscillation, and a suction chamber that supplies fluid into the bore, A discharge chamber that discharges the fluid compressed in the bore, a throttle passage that connects the discharge chamber and the crank chamber, an extraction passage that connects the crank chamber and the suction chamber, and a stator of the electromagnetic clutch. A new technical means is provided which includes an opening / closing valve that is incorporated and opens the bleed passage by the magnetic action of the electromagnetic clutch and closes the bleed passage by the disappearance of the magnetic action.

The second aspect of the present invention provides a control valve mechanism for adjusting the differential pressure between the suction chamber pressure and the crank chamber pressure, and changing the discharge fluid volume through the inclination displacement of the rotary swash plate.
A structure is used in which the air extraction passage is installed side by side.

[0007]

[Operation] When the electromagnetic clutch is turned off, the opening / closing valve that was previously opened by the magnetic action of the electromagnetic clutch is automatically closed to close the bleed passage and prevent the extraction of the working fluid from the crank chamber. To do. On the other hand, high-pressure working fluid is supplied from the discharge chamber to the crank chamber through the throttle passage until the compressor completely stops functioning, so the rotary swash plate rapidly tilts as the crank chamber pressure increases. Displaces to the reduction side to reduce the piston stroke and suppress load fluctuation shock at restart.

In the structure in which the control valve mechanism is provided in the bleed passage, when the bleed passage is opened by opening the on-off valve that follows the ON operation of the electromagnetic clutch, the control valve mechanism causes the suction chamber pressure to rise. The opening degree of the extraction passage is adjusted based on the above, and the discharge fluid capacity is changed through the fluctuation of the crank chamber pressure.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment embodying the first invention is shown in FIG.
It will be described based on. In the figure, a front housing 2 is connected to a front end of a cylinder block 1 which is a main component of a compressor, and a rear housing 3 having a suction chamber 3a and a discharge chamber 3b is connected to a rear end thereof via a valve plate 4. Has been done. A drive shaft 7, which is linked to an engine (not shown) through an electromagnetic clutch 6, is inserted into a crank chamber 5 formed in the front housing 2, and the drive shaft 7 rotates between the cylinder block 1 and the front housing 2. It is supported freely. A rotary base 8 is fixed on the drive shaft 7 of the crank chamber 5, and a long hole 9a is formed at the tip of a support arm 9 extending to the rear surface side of the rotary base 8 while the long hole 9a is formed. A pin 10 is slidably fitted in the pin 10, and a rotary swash plate 11 is tiltably connected to the pin 10.

That is, a sleeve 12 is loosely fitted on the drive shaft 7 adjacent to the rear end of the rotary base 8, and the sleeve 12
Pivot shafts 12a protruding from the left and right sides of the rotary swash plate 11 are fitted into engaging holes (not shown) of the rotary swash plate 11, so that the rotary swash plate 11 is rotated by the pivot shaft 1
It is supported so as to be tiltable around 2a. A swing plate 13 is supported on the rear end side of the rotary swash plate 11 so as to be relatively rotatable, and a guide portion 13a provided on an outer edge portion is provided with a through bolt 14
The rotation of the cylinder 16 is restricted by engaging with the cylinder block 1, and the pistons 16 in the plurality of bores 15 arranged in parallel to the cylinder block 1 and the swing plate 13 are articulated by connecting rods 17. Therefore, the rotary motion of the drive shaft 7 is converted into the back-and-forth swing of the swing plate 13 via the rotary swash plate 11, and the piston 16 is directly moved in the bore 15 to be sucked into the bore 15 from the suction chamber 3a. The refrigerant gas is compressed and discharged into the discharge chamber 3b.

The electromagnetic clutch 6 includes a front housing 2
Of the rotor 61, which is rotatably supported by the boss portion of the rotor 61 and is interlocked with the engine via a belt; A disk-shaped armature 64 arranged to face the friction surface, and the armature 64 as a buffer 6
A hub 66 that is connected to the drive shaft 7 via the main shaft 5 is configured as a main part. The on-off valve 2 is attached to the stator 63.
The on-off valve 20 is adapted to open and close the bleed passage 40 that connects the crank chamber 5 and the suction chamber 3a in response to the magnetic action of the electromagnetic clutch 6.

The on-off valve 20 will be described with reference to FIG. The on-off valve 20 includes a fixed iron core 22 internally fixed to a bottomed cylinder 21, a movable iron core 23 slidably fitted in the cylinder 21, and an opening of the cylinder 21. And a movable iron core 2 fixed to the valve base 24.
3 has a spherical valve 25 that can be brought into and out of contact with the tapered valve seat 23a, the cylinder 21 is loaded into the stator 63 of the electromagnetic clutch 6 in parallel with the drive shaft center, and the valve base 24 is provided in the front housing 2. It is fitted in a mounting hole 2a formed so as to penetrate from the front end surface toward the crank chamber 5.

The movable iron core 23 is urged between the fixed iron core 22 and the movable iron core 23 in a direction to separate the movable iron core 23 from the valve seat 23a.
A return spring 26 for abutting against the spherical valve 25 is interposed, and a spring chamber 26a of the return spring 26 has a through hole 23b opened in the valve seat 23a, a through hole 23c, and a through hole 21a of the cylinder 21.
On the other hand, the peripheral region of the spherical valve 25 seated on the valve seat 23a forms a part of a passage communicating with the valve seat 23a, and is constantly communicated with the crank chamber 5 through a through hole 24a formed in the valve base 24. The through hole 21a of the cylinder 21 is connected to the suction chamber 3a via the through hole 27 extending from the stator 63 to the outer surface of the front housing 2 and the conduit 28.
A series of passages sandwiching the above constitutes an extraction passage 40 that connects the crank chamber 5 and the suction chamber 3a. Therefore, at the same time that the electromagnetic clutch 6 is activated by energizing the electromagnetic coil 62, the movable iron core 23 is attracted to the fixed iron core 22 by its magnetic action, and the valve seat 23a is released (opened) from the spherical valve 25. The extraction passage 40 is opened. Reference numeral 41 is a throttle passage that connects the discharge chamber 3b and the crank chamber 5 to each other and constantly supplies a high-pressure working fluid (discharge refrigerant gas) to the crank chamber 5.

Next, the operation of this embodiment will be described.
First, when the electromagnetic clutch 6 is energized to start the compressor, the magnetic action of the electromagnetic clutch 6 causes the movable iron core 2 to move.
3 is attracted to the fixed iron core 22 against the biasing force of the return spring 26, and the valve seat 23a is separated from the spherical valve 25 to open the bleed passage 40 (FIG. 1). Therefore,
Although a high-pressure working fluid is constantly supplied to the crank chamber 5 from the discharge chamber 3b through the throttle passage 41, the crank chamber 5 and the suction chamber 3a are maintained at the same pressure state, and the rotary swash plate 11 and the swing plate 13 are held. Gradually shifts to the maximum tilt posture, and the compressor
It is operated at 00% capacity.

At the same time that the electromagnetic clutch 6 is de-energized to stop the compressor, the magnetic action acting on the on-off valve 20 disappears and the suction force of the fixed iron core 22 is naturally lost. The movable iron core 23 slides by the urging force of the return spring 26 so that the spherical valve 25 is seated (closed) on the valve seat 23a (FIG. 3). Even after the extraction of the working fluid from the crank chamber 5 is blocked by closing the bleed passage 40 as described above, the high-pressure working fluid is still cranked through the throttle passage 41 until the function of the compressor is completely stopped. Since it is supplied to the chamber 5, the rotary swash plate 11 and the oscillating plate 13 are rapidly displaced to the tilt angle reducing side with the increase in pressure in the crank chamber 5 to reduce the piston stroke, and a load fluctuation shock at the time of restart is generated. Suppress.

Next, an embodiment of the second invention will be described with reference to FIG. According to the second aspect of the present invention, a control valve mechanism that changes the discharge fluid volume through the inclination displacement of the rotary swash plate is provided in the bleed passage to suppress the load fluctuation shock at the time of starting the compressor, and at the same time, originally It also has a variable capacity function. In the figure, the extraction passage 4 is connected to the pipe 28.
A control valve mechanism 30 for adjusting the opening degree of the passage 29 is provided in the passage 29 in the rear housing 3 which constitutes a part of 0. That is, the accommodating chamber 3 that is concentrically aligned with the passage 29 and that is open to the rear end surface of the rear housing 3.
A bellows 32 is housed in the inside of the housing 1, and the base end thereof is a housing chamber 3
The sealing plate 34, which is connected to the support ring 33 that is fixedly fitted into the mouth end of 1 and is connected to the tip end of the support ring 1, further includes the passage 2
The base shaft portion of the spherical valve body 36 for adjusting the opening degree of the valve hole 35 formed by the opening 6 is joined. A control spring 38 is interposed between a spring receiver 37 screwed to the support ring 33 and the sealing plate 34, and urges the spherical valve body 36 in a direction to reduce the opening of the valve hole 35. is doing. Thus, the internal air space of the bellows 32 forms an air chamber 39 communicating with the outside air through the through hole penetrating the spring receiver 37, while the air space in the storage chamber 31 surrounding the bellows 32 is At the same time as forming a part of the extraction passage communicating with the suction chamber 3a through the passage 28,
It substantially forms a pressure-sensitive chamber that opposes the biasing force applied to the bellows.

Therefore, when the compressor is started by energizing the electromagnetic clutch 6 and the bleed passage 40 is opened by the opening operation of the opening / closing valve 20 based on the magnetic action of the electromagnetic clutch, the suction chamber is opened via the passage 29a. The space in the storage chamber 31 communicating with 3a is moved to the bellows 32 by the suction chamber pressure.
The spherical valve element 36 while counteracting the urging force of the spherical valve element 36 in response to the supply of the working fluid (discharged refrigerant gas) through the throttle passage 41.
Since the opening degree of the extraction passage (valve hole 35) is adjusted by
The crank chamber pressure changes in accordance with the fluctuation of the cooling load, and this is reflected in the tilt angle of the rotary swash plate 11 and the oscillating plate 13 and the piston stroke, and the discharge fluid volume is adjusted at any time.

In each of the above-mentioned embodiments, the description has been given of the compressor in which the oscillating plate is connected to the piston by the connecting rod, but the present invention is not limited to this.
Of course, it is also applicable to a compressor configured so that the rotary swash plate is directly linked to the piston via a shoe or the like.

[0019]

As described above in detail, according to the structure of the present invention, when the compressor is stopped, the electromagnetic clutch is de-energized and, at the same time, the electromagnetic clutch opens the valve. The on-off valve is automatically closed to close the bleed passage, and until the compressor function is completely stopped, the high-pressure working fluid is supplied to the crank chamber through the throttle passage to reduce the inclination of the rotating swash plate. Since the displacement can be reduced, the load fluctuation shock can be suppressed based on the reduction of the piston stroke at the time of restart, and the power performance and the driving feeling can be improved. In particular, in the present invention, since the on-off valve is incorporated in the stator of the electromagnetic clutch, it is possible to expect proper valve operation due to the strong magnetic field.

[Brief description of drawings]

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

FIG. 2 is a sectional view showing an embodiment of the second invention.

FIG. 3 is an enlarged sectional view showing an on-off valve.

[Explanation of symbols]

3a is a suction chamber, 3b is a discharge chamber, 5 is a crank chamber, 6 is an electromagnetic clutch, 7 is a drive shaft, 11 is a rotating swash plate, 16 is a piston, 20 is an opening / closing valve, 30 is a control valve mechanism, and 40 is an extraction passage. , 41 are throttle passages

Claims (2)

[Claims] 1. A drive shaft that is connected to an electromagnetic clutch and extends into a crank chamber, a rotary swash plate that rotates together with the drive shaft in the crank chamber, and that is capable of tilt displacement according to the crank chamber pressure, and the rotation. A piston that is linked to the swash plate and that linearly moves in each bore based on its rotational oscillation, a suction chamber that supplies fluid into the bore, and a discharge chamber that discharges the fluid compressed in the bore. A throttle passage that connects the discharge chamber and the crank chamber, a bleed passage that connects the crank chamber and the suction chamber, and a stator of the electromagnetic clutch, and the bleed passage is opened by the magnetic action of the electromagnetic clutch. A compressor including an opening / closing valve that closes the bleed passage by the disappearance of the magnetic action. 2. A control valve mechanism for adjusting the differential pressure between the suction chamber pressure and the crank chamber pressure and changing the discharge fluid volume through the tilt displacement of the rotary swash plate is provided in the bleed passage. The compressor according to claim 1, wherein