JPH0968160A - Piston type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the noise level in a cabin by reducing fluctation of torque which causes torsional vibration. SOLUTION: Subsidiary compression chambers 80, 81 are formed in rotary valves 78, 79 integrally rotated with a drive shaft 33. With the rotation of the rotary valves 78, 79, open port passages 83, 84 of the subsidiary compression chambers 80, 81 are connected to passages 85, 86 in the compression stroke of compression chambers 60, 61. The compression chambers 60, 61 are connected to the subsidiary compression chambers 80, 81. In the suction stroke of the compression chambers 60, 61 the passage 85, 86 are closed by the peripheral surface of the rotary valves 78, 79 and connections between the compression chambers 60, 61 and the subsidiary compression chambers 80, 81 are intercepted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor used in, for example, a vehicle air conditioner.

[0002]

2. Description of the Related Art In a piston type compressor of this type, a swash plate is integrally rotatably mounted on a drive shaft, and a plurality of cylinder bores for accommodating pistons in a cylinder block are formed. Then, the refrigerant gas in the compression chamber is compressed by the reciprocating motion of the piston in the cylinder bore based on the rotation of the swash plate.

In the piston type compressor, a compression reaction force is generated as the piston compresses. This compression reaction force acts on the drive shaft via the swash plate, and torque fluctuation having a frequency component corresponding to the number of cylinders is generated. This torque fluctuation excites the torsional vibration of the drive shaft-clutch system, and further causes a resonance phenomenon in the compressor and an auxiliary machine connected thereto, which causes noise.

In order to solve such a problem, for example, Japanese Patent Application Laid-Open No. 55-20908 discloses an electromagnetic clutch of a compressor which can tolerate a torsion load. In this electromagnetic clutch, a driven disk and a connecting plate that faces the driven disk are joined to each other by saw-tooth inclined portions that are continuously formed in the circumferential direction. A damper body for allowing a torsional load is provided on the back of the one saw-toothed inclined portion, and the driven disk and the connecting plate are connected by a spring.

Further, in the piston type compressor as described above, the volume (dead volume) of the compression chamber when the piston reaches the top dead center is increased by forming a recess in the head of the piston or the like. Then, a configuration is known in which the amplitude of torque fluctuation is reduced.

[0006]

However, in the electromagnetic clutch described in the above publication, the clutch becomes large and heavy. Generally, when the ratio of the clutch portion to the total mass of the compressor increases, the center of gravity of the compressor is biased to the front side. Such movement of the center of gravity may cause a new vibration, and there is a problem that the clutch is difficult to use.

Further, as shown in FIG. 6 (b), in the piston type compressor (conventional example (2)) in which the dead volume in the compression chamber is enlarged, the same measure as shown in FIG. 6 (a) is taken. Compared to a normal piston type compressor (conventional example (1)) which does not exist, a delay occurs until the pressure in the compression chamber becomes equal to the pressure in the suction pressure region in the suction stroke. Therefore, the stroke of the piston effective for sucking the refrigerant gas into the compression chamber is shortened, and the amount of the refrigerant gas sucked into the compression chamber is reduced. In this state, if the dead volume is set excessively large, the pressure in the compression chamber may not reach the predetermined pressure even when the piston reaches the top dead center. Then, the piston moves toward the bottom dead center without the refrigerant gas in the compression chamber being discharged to the discharge chamber. That is, there is a limit even if the dead volume is increased, and there is a problem that the torque fluctuation cannot be reduced to a desired level only by increasing the dead volume.

An object of the present invention is to provide a compressor capable of reducing the torque fluctuation which is the exciting force of the torsional vibration and reducing the noise level in the passenger compartment.

[0009]

In order to achieve the above object, according to the present invention, a plurality of cylinder bores are arranged around a drive shaft in a cylinder block, and a piston is housed in the cylinder bore. Then, the compression chamber is partitioned and formed, and in the piston type compressor configured to reciprocate the piston in association with the rotation of the drive shaft to compress the refrigerant gas, a sub-compression chamber communicating with the compression chamber is provided. An on-off valve is provided to open and close between the auxiliary compression chamber and the compression chamber, and the on-off valve is closed during the intake stroke.

According to a second aspect of the present invention, in the first aspect of the invention, the opening / closing valve is opened before the volume of the compression chamber in the compression stroke reaches approximately one half of the compression start time. It is the one.

According to a third aspect of the invention, in the second aspect of the invention, the on-off valve performs the opening / closing operation in synchronization with the rotation of the drive shaft. According to a fourth aspect of the present invention, in the third aspect of the invention, the on-off valve is a rotary valve that is integrally rotatably supported by the drive shaft.

According to a fifth aspect of the invention, in the invention of the fourth aspect, the auxiliary compression chamber is formed inside the rotary valve. In the invention according to claim 6,
In the invention according to any one of claims 1 to 5, a discharge passage for discharging the refrigerant gas in the sub compression chamber to a predetermined chamber is provided.

According to a seventh aspect of the invention, in the invention of the sixth aspect, the predetermined chamber is a compression chamber in another compression stroke. Therefore, according to the invention described in claims 1 and 2, when the compression chamber is in the suction stroke,
The on-off valve between the compression chamber and the sub compression chamber communicating with the compression chamber is closed, and the compression chamber and the sub compression chamber are shut off from each other.
Therefore, the capacity of the compression chamber is not expanded in this suction stroke, and there is no delay until the pressure in the compression chamber and the pressure in the suction pressure region become equal. And
The stroke of the piston effective for sucking the refrigerant gas into the compression chamber is not shortened, and the refrigerant gas is sufficiently introduced into the compression chamber in this suction stroke.

When the piston shifts to the compression stroke, the on-off valve is opened before the volume in the compression chamber reaches about half of the volume at the start of compression, and the compression chamber and the sub compression chamber communicate with each other. To be done. In other words, the compression chamber and the sub-compression chamber communicate with each other before the pressure in the compression chamber rises sharply, and the capacity of the compression chamber is expanded. Due to this capacity expansion, the pressure in the compression chamber rises gently during the compression stroke, as compared to a normal compressor that does not take the same measure. Here, it has been observed that the steepness of the pressure rise in the compression chamber during the compression stroke is related to the magnitude of the amplitude of the torque fluctuation due to the compression reaction force. That is, when the pressure increase is rapid, the amplitude of the torque fluctuation is large, and conversely, when the pressure increase is moderate, the amplitude of the torque fluctuation is small. Therefore, the compressor whose capacity has been expanded as described above has a smaller amplitude of torque fluctuation than the conventional compressor.

According to the third aspect of the invention, the piston in the cylinder bore is reciprocated in association with the rotation of the drive shaft to compress the refrigerant gas in the compression chamber. Further, the opening / closing valve between the compression chamber and the sub compression chamber is opened / closed in synchronization with the rotation of the drive shaft. Therefore, the cycle of the compression operation in the compression chamber and the timing of the opening / closing operation of the opening / closing valve can be easily and reliably synchronized.

According to the invention as set forth in claim 4, since the on-off valve is a rotary valve which is integrally rotatable with the drive shaft, the compressor body and the sub-compression chamber are prevented from increasing in size. Can be opened and closed between and.

According to the fifth aspect of the present invention, the sub compression chamber is formed in the rotary valve, and the compression chamber and the sub compression chamber communicate with each other only in the compression stroke, thereby reducing torque fluctuation. To be done. Therefore, torsional vibration can be reduced without increasing the size of the compressor body. In addition, the center of gravity of the compressor body does not move, and there is almost no possibility of generating a new vibration generation factor.

According to the sixth aspect of the present invention, the compressed high-pressure refrigerant gas in the sub-compression chamber is discharged to a room different from the compression chamber communicated immediately before through the discharge passage, and the sub-compression chamber is discharged. The pressure in the compression chamber is returned to the low pressure state. Therefore, when the compression chamber and the auxiliary compression chamber are communicated with each other in the compression stroke, the effect of volume expansion in the compression stroke is not impeded.

According to the seventh aspect of the invention, the refrigerant gas discharged into the compression chamber in the other compression stroke is discharged into the discharge chamber due to the compression operation in the compression chamber. Therefore, the refrigerant gas in the sub-compression chamber is apparently shifted in the discharge timing, and there is almost no inconvenience such as a reduction in the volumetric efficiency of the compressor.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, the accommodation chamber 2 is provided at the center of the pair of front and rear cylinder blocks 21, 22 that are joined together.
3 and 24 are pierced. Cylinder block 21, 2
Valve plates 25 and 26 are joined to the end surface of 2, and support holes 27 and 28 are formed through the valve plates 25 and 26. Annular positioning protrusions 29 and 30 are provided on the periphery of the support holes 27 and 28, and the positioning protrusions 29 and 30 are fitted into the accommodating chambers 23 and 24.

Support holes 27 for the valve plates 25, 26,
28, the drive shaft 33 has conical roller bearings 34, 35.
Is rotatably supported via the drive shaft 33.
A swash plate 36 is fixedly supported on the. A suction flange 38 is formed in each of the cylinder blocks 21 and 22 forming the crank chamber 37, and an external refrigerant circuit (not shown) is connected to the suction flange 38.

As shown in FIGS. 4 and 5, the cylinder blocks 21 and 22 are formed with a plurality of cylinder bores 39 and 40 at equidistant angular positions about the drive shaft 33. As shown in FIG. 1, a double-headed piston 41 is reciprocally housed in a pair of front and rear cylinder bores 39, 40. Hemispherical shoes 42 and 43 are interposed between the double-headed piston 41 and both front and rear surfaces of the swash plate 36. Therefore, when the swash plate 36 rotates,
A double-headed piston 41 reciprocates in the cylinder bores 39, 40.

A front housing 44 is joined to the front end surface of the valve plate 25, and the valve plate 26
A rear housing 45 is joined to the rear end surface. On the inner wall surfaces of both housings 44 and 45, the annular pressing portion 4
6, 47 are projected. The pressing portion 46 of the front housing 44 and the outer race 34a of the conical roller bearing 34
An annular plate-shaped preloading spring 48 is interposed between and. The pressing portion 47 of the rear housing 45 is in contact with the outer race 35 a of the conical roller bearing 35. Rollers 34b and 35b together with outer races 34a and 35a
The inner races 34c and 35c that sandwich the drive shaft 3 are
It is in contact with the stepped portions 49 and 50 of No. 3. The cylinder blocks 21, 22, the valve plates 25, 26, the front housing 44, and the rear housing 45 are fastened and fixed by bolts 51. Conical roller bearings 34, 35
Receives both radial and thrust loads on the drive shaft 33. The tightening of the bolts 51 causes the preload applying spring 48 to flex and deform, and this flexural deformation applies a preload in the thrust direction to the drive shaft 33 via the conical roller bearing 34.

Suction chambers 52 and 53 are formed on the outer peripheral sides of both housings 44 and 45, and discharge chambers 54 and 55 are formed on the inner peripheral sides. The suction chambers 52 and 53 communicate with the crank chamber 37 via suction passages 56 and 57. Further, the suction chambers 52 and 53 are provided in the valve plate 2
It is connected to the compression chambers 60 and 61 defined in the cylinder bores 39 and 40 by the double-headed piston 41 via the suction ports 58 and 59 on the valves 5 and 26. Inhalation port 58, 59
Are opened and closed by flapper valve type suction valves 62 and 63. The discharge chambers 54, 55 are connected to the compression chambers 60, 61 via discharge ports 64, 65 on the valve plates 25, 26. The discharge ports 64 and 65 are opened and closed by flapper valve type discharge valves 66 and 67. Discharge valve 66, 67
The opening degree of is controlled by the retainers 71 and 72. The retainers 71, 72 are sandwiched between the annular projections 68, 69 of the housings 44, 45 and the valve plates 25, 26. The discharge chamber 55 is provided through the discharge passage 73 in the rear housing 45, the discharge passage 74 in the drive shaft 33, and the discharge passage 75 in the front housing 44.
It is connected to 4. The discharge chamber 54 has a discharge flange 76.
Via an external refrigerant circuit (not shown). The lip seal 77 is interposed between the peripheral surface of the drive shaft 33 and the front housing 44 and prevents the refrigerant gas from leaking from the discharge chamber 54 to the outside of the compressor.

As shown in FIGS. 1 to 3, the accommodation chamber 2
3 and 24, the stepped portion 49 of the drive shaft 33,
50 is a pair of substantially cylindrical rotary valves 7
8, 79 are rotatably supported integrally. Sub-compression chambers 80, 81 are defined between the inner peripheral surfaces of the rotary valves 78, 79 and the outer peripheral surface of the drive shaft 33.
A seal ring 82 is provided between the rotary valves 78 and 79 and the drive shaft 33 to prevent pressure leakage of the auxiliary compression chambers 80 and 81. The outer peripheral surfaces of the rotary valves 78 and 79 are in surface contact with the inner peripheral surfaces of the accommodation chambers 23 and 24. The rotary valves 78 and 79 have circumferential walls provided with opening passages 83 and 84 of the auxiliary compression chambers 80 and 81 having a long hole shape so as to extend in the circumferential direction.

Passageways 85 and 86 are formed in the cylinder blocks 21 and 22 to connect the cylinder bores 39 and 40 to the accommodating chambers 23 and 24. This passage 8
The cylinder bores 39, 40 of the valves 5, 86 are open near the valve plates 25, 26. Also, passage 8
The accommodating chamber sides of 5, 86 are opened so as to correspond to the rotation loci of the opening passages 83, 84 of the auxiliary compression chambers 80, 81.

Looking at the specific compression chambers 60 and 61, as shown in FIGS. 1, 4 and 5, the refrigerant gas is moved as the double-headed piston 41 moves from the top dead center side to the bottom dead center side. During the suction stroke in which the air is sucked into the compression chambers 60, 61, the opening passages 8 of the sub-compression chambers 80, 81 are entirely covered.
3, 84 are adapted to be disengaged from the corresponding positions of the passages 85, 86. That is, the compression chambers 60 and 61 and the sub-compression chambers 80 and 81 are shut off from each other. From this state, when the drive shaft 33 rotates to move to the compression stroke in which the refrigerant gas is compressed from the compression chambers 60 and 61 as the double-headed piston 41 moves from the bottom dead center side to the top dead center side, the rotary shaft is rotated. The valves 78 and 79 also rotate synchronously. Then, the opening passages 83, 84 are moved to corresponding positions with the passages 85, 86 in accordance with the rotation of the rotary valves 78, 79 before the volume inside the compression chambers 60, 61 becomes approximately half. To do. The compression chambers 60 and 61 and the auxiliary compression chamber 8
0 and 81 are in communication with each other. Next, when the double-headed piston 41 reaches near the top dead center, the opening passage 83,
84 is displaced from the position corresponding to the passages 85 and 86 as the rotary valves 78 and 79 are rotated. That is, the compression chambers 60 and 61 and the auxiliary compression chambers 80 and 81 are in a state of being disconnected again.

At the very beginning of the suction stroke, in which the double-headed piston 41 starts to move from the top dead center to the bottom dead center, the compressed refrigerant gas slightly remaining in the compression chambers 60 and 61 is re-expanded. Further, in the very early stage of the compression stroke in which the double-headed piston 41 starts to move from the bottom dead center to the top dead center, inertial suction of the refrigerant gas occurs in the compression chambers 60, 61 due to the closing delay of the suction valves 62, 63. To do. However, the re-expansion and the inertial suction are very short time, and the mutual switching between the suction stroke and the compression stroke is substantially synchronized with the top dead center position or the bottom dead center position of the double-headed piston 41.

Next, the operation of the compressor configured as described above will be described. When the drive shaft 33 is rotated by an external drive source such as a vehicle engine, the crank chamber 3
The swash plate 36 in 7 is rotated, and the plurality of double-headed pistons 41 are reciprocated in the cylinder bores 39, 40 via the shoes 42, 43. The refrigerant gas guided from the suction flange 38 to the crank chamber 37 by the movement of the double-headed piston 41 is guided to the suction chambers 52, 53 from the crank chamber 37 via the suction passages 56, 57. And the suction chambers 52, 53
The refrigerant gas therein is guided into the compression chambers 60, 61 through the suction ports 58, 59 and is compressed by the double-headed piston 41.

Here, attention is paid to the compression operation of one of the compression chambers 60 and 61. At the time when the volume inside the compression chambers 60, 61 has not reached almost half of the time when the compression is started,
The compression chambers 60, 61 are communicated with the sub compression chambers 80, 81 in the rotary valves 78, 79. That is, the compression chamber 60,
In the situation where the pressure in 61 does not rise so much,
The volumes of the compression chambers 60 and 61 are expanded.
Therefore, as shown in FIG. 6C, the subsequent compression curve of the refrigerant gas is gentler than that of the conventional example (1) in which the volume is not expanded in the compression stroke shown in FIG. 6A. Become.

The refrigerant gas compressed in the compression chambers 60, 61 passes through the discharge ports 64, 65 and the discharge chamber 54,
It is discharged to 55. Further, the compressed refrigerant gas in the discharge chambers 54 and 55 is discharged into the discharge passages 73 to 75 and the discharge flange 76.
After that, it is supplied to a condenser, an expansion valve, and an evaporator that form an external refrigerant circuit, and is used for air conditioning in the vehicle compartment.

When the piston 41 reaches the vicinity of the top dead center, the piston 41 blocks the openings of the passages 85 and 86 on the compression chambers 60 and 61 side. Further, the openings of the passages 85 and 86 on the accommodation chamber 23, 24 side are closed by the outer peripheral surfaces thereof as the rotary valves 78, 79 rotate. Then, the opening passages 83, 84 of the auxiliary compression chambers 80, 81 reach the positions corresponding to the passages 85, 86 communicating with the compression chambers 60, 61 during the next compression as the compression chambers of the other compression strokes. That is, the opening passages 83 and 84 also serve as discharge passages for discharging the refrigerant gas in the sub compression chambers 80 and 81 to a predetermined chamber. Therefore, the compressed refrigerant gas in the sub-compression chambers 80, 81 is discharged to the compression chambers 60, 61 in the middle of compression and is eventually discharged to the discharge chambers 54, 55.

Next, the action of reducing the torsional vibration of the compressor constructed as described above will be described. In the compressor of this embodiment, in the compression stroke, before the pressure in the compression chambers 60, 61 rises sharply, the compression chambers 60, 61 and the auxiliary compression chamber 8
0 and 81 are communicated with each other, and the capacity of the compression chambers 60 and 61 is expanded. Therefore, as compared with the conventional compressor (conventional example (1)) that does not expand the capacity in the compression stroke, the compression chamber 6
The refrigerant gas in 0 and 61 is compressed slowly. Then, as shown in FIG. 7, it is possible to reduce the amplitude of the torque fluctuation which is the exciting force of the torsional vibration. Further, the amplitude of the torque fluctuation of the compressor of this embodiment is smaller than that of the conventional example (2).

When the fast Fourier transform analysis is performed based on the torque fluctuation curve of FIG. 7, the magnitude of each order component of the frequency of torsional vibration can be calculated. Here, FIG.
In the case of the 10-cylinder type compressor as shown in FIG. 5, the rotational 10th-order component and the rotational 20th-order component are frequency components that are particularly related to the increase and decrease of the noise level in the vehicle interior. FIG.
As shown in FIG. 1, in the compressor of this embodiment, the conventional example (1)
And, compared with the conventional example (2), the rotation 10th order component and the rotation 2
Both of the zero-order components are significantly reduced. Along with this, the resonance phenomenon in the compressor and the auxiliary machine connected thereto is reduced, and the generation of noise is suppressed.

According to the present embodiment configured as described above, the following excellent effects are exhibited. (1) In the suction stroke, the compression chambers 60, 61 and the auxiliary compression chambers 80, 81 are shut off,
Does not expand in volume. Therefore, simply the compression chamber 6
Delay until the pressures in the compression chambers 60, 61 and the pressures in the suction chambers 52, 53 become equal to those generated in the conventional compressor (conventional example (2)) in which the dead volume of 0, 61 is enlarged. Does not occur. Then, the stroke of the piston 41 effective for sucking the refrigerant gas into the compression chambers 60 and 61 is not shortened, and the refrigerant gas is sufficiently introduced into the compression chambers 60 and 61 in this suction stroke.

(2) In the compression stroke, the compression chamber 6
0 and 61 are communicated with the auxiliary compression chambers 80 and 81, and the capacities of the compression chambers 60 and 61 are expanded. For this reason, the refrigerant gas in the compression chambers 60 and 61 is compressed more slowly than in a conventional compressor that does not expand the capacity in the compression stroke.
Then, the amplitude of the torque fluctuation, which is the exciting force of the torsional vibration, can be reduced. For example, in the case of a 10-cylinder type compressor, the rotational 10th-order component and the rotational 20th-order component of the frequency of the torsional vibration are significantly reduced. can do. Therefore,
The resonance phenomenon in the compressor and the auxiliary equipment connected thereto is reduced, the generation of noise is suppressed, and the noise level in the vehicle compartment can be reduced.

(3) As described above, since the compression is performed gently, the refrigerant gas compression chamber 60, which is caused by the discharge resistance of the discharge valves 66 and 67, is compared with the conventional compressor.
Over-compression in 61 is suppressed. Therefore, the power loss due to the overcompression can be reduced.

(4) The compression operation of the refrigerant gas in the compression chambers 60 and 61 is performed by the reciprocating motion of the piston 41 which is interlocked with the rotation of the drive shaft 33. Also, the compression chambers 60, 61
The passages 85 and 86 between the auxiliary compression chambers 80 and 81 are opened and closed by the rotary valve 7 that rotates in synchronization with the drive shaft 33.
8 and 79. Therefore, the compression chambers 60, 6
The period of the compression operation in 1 and the timing of adjusting the compression capacity can be easily and reliably synchronized.

(5) Compression chambers 60 and 61 and sub compression chamber 8
Since the opening / closing valves of the passages 85 and 86 between the compressors 0 and 81 are the rotary valves 78 and 79, the size of the compressor body does not increase. Moreover, since an expensive solenoid valve or the like is not used, the compressor can be made inexpensive.

(6) The sub compression chambers 80, 81 are formed in the rotary valves 78, 79, and the compression chambers 60, 61 are communicated with the sub compression chambers 80, 81 only during the compression stroke, so that the torque is reduced. Variability is reduced. Therefore, the torsional vibration can be reduced without increasing the size of the compressor body as in the conventional vibration reducing mechanism in the clutch. Further, there is almost no possibility that the center of gravity of the compressor body will move and a new factor of vibration will be generated.

(7) The compressed high-pressure refrigerant gas in the sub compression chambers 80, 81 is discharged to the compression chambers 60, 61 in the first half of the next compression stroke as the rotary valves 78, 79 rotate. Then, the refrigerant gas released into the compression chambers 60 and 61 is discharged to the discharge chambers 54 and 55 due to the compression operation inside the compression chambers 60 and 61. For this reason, the refrigerant gas in the sub compression chambers 80, 81 is apparently only in a state where the discharge timing is shifted, and there is almost no inconvenience such as a decrease in the volumetric efficiency of the compressor.

(Second Embodiment) Next, a second embodiment of the present invention will be described focusing on parts different from the first embodiment.

In the second embodiment, as shown in FIG. 9, the auxiliary compression chamber 91 is formed in the solenoid valve 93 as an on-off valve provided in the rear housing 92. The electromagnetic valve 93 is controlled in synchronization with the rotation of the drive shaft 33 to open and close a passage 94 between the compression chamber 61 and the sub compression chamber 91. Further, the discharge passage 9 is provided between the sub compression chamber 91 and the suction chamber 53.
5 is formed, and the refrigerant gas in the sub compression chamber 91 is returned to the suction chamber 53.

Next, the operation of the solenoid valve 93 will be described. The solenoid 96 of the solenoid valve 93 is controlled to be demagnetized by the control computer 97 based on the detected rotation speed information from the rotation speed detector (not shown) of the drive shaft 33. Here, the control computer 97 determines whether the piston 41 is in the suction stroke or the compression stroke based on the detected rotation speed information. When the piston 41 is in the intake stroke, the solenoid 96 is demagnetized, and the valve body 98 is urged by the return spring 99 to urge the passage 94.
Is closed. That is, when the piston 41 is in the suction stroke, the compression chamber 61 and the sub compression chamber 91 are shut off from each other.

Here, when the piston 41 shifts to the compression stroke, the solenoid 96 is excited by the excitation command of the control computer 97, and the valve body 98 opens the passage 94 against the biasing force of the return spring 99 and discharges it. Move to close the passage 95. When the piston 41 is in the compression stroke, the compression chamber 61 and the auxiliary compression chamber 91 are communicated with each other, and the volume of the compression chamber 61 is expanded. Note that FIG. 9 shows a state in which the solenoid 96 is in an excited state and the compression chamber 61 and the auxiliary compression chamber 91 are in communication with each other.

Immediately before the piston 41 shifts to the suction stroke, the solenoid 96 is demagnetized by the degaussing command of the control computer 97, the valve body 98 closes the passage 94 by the urging force of the return spring 99, and the discharge passage. Move to open 95. Then, the high-pressure refrigerant gas in the sub compression chamber 91 is discharged into the suction chamber 53 through the discharge passage 95, and the inside of the sub compression chamber 91 becomes a low pressure state which is the same as the suction pressure. Therefore, when the compression chamber 61 and the sub-compression chamber 91 are communicated again in the compression stroke, the high-pressure refrigerant gas is not returned to the same compression chamber 61 in the sub-compression chamber 91, and the volume expansion in the compression stroke is performed. The effect of is not hindered.

Even with this structure, the volume of the compression chamber 61 can be increased only during the compression stroke, and the amplitude of torque fluctuation, which is the exciting force of torsional vibration, can be reduced.

(Third Embodiment) Next, a third embodiment of the present invention will be described focusing on the points different from the first embodiment.

In the third embodiment, as shown in FIGS. 10 and 11, the auxiliary compression chambers 101 and 102 are the inner peripheral surfaces of the accommodating chambers 105 and 106 of the cylinder blocks 103 and 104 and the rotary valves 107 and 108. Is formed between the outer peripheral surface and. On the outer peripheral surfaces of the rotary valves 107 and 108, the passages 85 and 86 and the auxiliary compression chambers 101 and 102 are formed.
Recesses 109 and 110 are formed to connect with.

The opening / closing operation of the passage 85 by the rotary valve 107 on one side will now be described. As shown in FIGS. 10 to 12, when the double-headed piston 41 is in the intake stroke, the recess 109 is disengaged from the corresponding position of the passage 85 throughout the intake stroke. That is, the compression chamber 60 and the sub-compression chamber 101 are shut off from each other. From this state, when the double-headed piston 41 shifts to the compression stroke, the concave portion 109 corresponds to the passage 85 with the rotation of the rotary valve 107 before the volume in the compression chamber 60 becomes approximately one half. Move to. Then, the compression chamber 60 and the auxiliary compression chamber 101 are in communication with each other. Next, when the double-headed piston 41 reaches the vicinity of the top dead center, the recess 109 is displaced from the position corresponding to the passage 85 as the rotary valve 107 rotates. That is, the compression chamber 60 and the sub compression chamber 101 are in a state of being disconnected again. In addition, the rotary valve 108 on the other side
The opening / closing operation of the passage 86 is also performed in the same manner.

Even with this structure, the volumes of the compression chambers 60 and 61 can be increased only during the compression stroke.
It is possible to reduce the amplitude of torque fluctuation, which is the exciting force of torsional vibration, without increasing the size of the compressor body.

The present invention can be modified and embodied as follows. (1) Embodying the present invention in a one-sided piston type compressor. (2) Embodying the present invention in a variable displacement compressor.

(3) Embodying the present invention in a wave cam plate type compressor. (4) Embodying the present invention in a vane compressor. For example, an auxiliary compression chamber is defined inside the rotor that rotates integrally with the drive shaft, and an opening / closing valve is provided between the auxiliary compression chamber and the compression chamber, and the opening / closing valve is provided only in the compression stroke in which the volume of the compression chamber decreases. Be configured to open.

(5) Embodying the present invention in a scroll compressor. Next, the technical idea grasped by the above embodiment will be described. (1) The piston type compressor according to claim 6, wherein the refrigerant gas in the sub compression chamber is formed so as to be discharged to a suction pressure region.

Even with this structure, when the compression chamber and the sub-compression chamber communicate with each other in the compression stroke, the sub-compression chamber is in a low pressure state, and the effect of volume expansion in the compression stroke is hindered. Never.

(2) A compression chamber is formed in the housing,
In a compressor adapted to compress a refrigerant gas by reducing the volume in the compression chamber in association with the rotation of a drive shaft, a sub-compression chamber communicating with the compression chamber is provided, and the sub-compression chamber and the compression chamber Equipped with an on-off valve for opening and closing
A compressor whose on-off valve closes the passage in the intake stroke.

(3) The compressor according to the item (2), wherein the on-off valve opens the passage before the volume in the compression chamber reaches about half of the volume at the start of compression in the compression stroke. .

[0059]

As described above in detail, the present invention has the following excellent effects. According to the first and second aspects of the present invention, when the compression chamber is in the suction stroke, the stroke of the piston effective for sucking the refrigerant gas into the compression chamber is not shortened, and the refrigerant gas is sufficiently supplied. It is introduced into the compression chamber. Then, when the compression chamber is in the compression stroke, the pressure rise in the compression chamber becomes gentle and the amplitude of the torque fluctuation becomes small. Therefore, the rotational nth-order component or the rotational 2nd-order component of the frequency of the torsional vibration in the n-cylinder compressor is reduced, and the resonance phenomenon in the compressor and the auxiliary machinery connected thereto is reduced. Then, the generation of noise is suppressed, and the noise level in the vehicle compartment can be reduced.

According to the third aspect of the present invention, the cycle of the compression operation in the compression chamber and the timing of the opening / closing operation of the on-off valve between the compression chamber and the auxiliary compression chamber can be simply and surely synchronized. You can

According to the invention described in claims 4 and 5, torsional vibration can be reduced without increasing the size of the compressor body. Further, the center of gravity of the compressor body does not move, and there is almost no possibility of generating a new vibration generation factor.

According to the sixth aspect of the invention, when the compression chamber and the auxiliary compression chamber are communicated with each other in the compression stroke, the auxiliary compression chamber is in a low pressure state, and the volume expansion effect in the compression stroke is achieved. Will not be hindered.

According to the invention as set forth in claim 7, the refrigerant gas in the sub-compression chamber is apparently only in a state in which the discharge timing is shifted, which causes inconvenience such as a reduction in the volumetric efficiency of the compressor. There is almost no.

[Brief description of drawings]

FIG. 1 is a sectional view showing a compressor according to a first embodiment.

FIG. 2 is an enlarged partial sectional view showing a main part of FIG.

FIG. 3 is a perspective view showing a rotary valve.

FIG. 4 is a sectional view taken along line 4-4 in FIG. 1;

5 is a sectional view taken along line 5-5 of FIG.

6A is an explanatory view showing a relationship between a volume and a pressure in a compression chamber of the present invention, FIG. 6A being a conventional example (1), FIG. 6B being a conventional example (2), and FIG.

FIG. 7 is an explanatory diagram regarding the amplitude of torque fluctuation.

FIG. 8 is an explanatory diagram showing the magnitude of each order component of torsional vibration.

FIG. 9 is a partial cross-sectional view showing the main parts of the compressor of the second embodiment.

FIG. 10 is a sectional view showing a compressor of a third embodiment.

11 is an enlarged partial cross-sectional view showing the main parts of FIG.

12 is a sectional view taken along line 12-12 of FIG.

[Explanation of symbols]

21, 22, 103, 104 ... Cylinder block, 33
... Drive shafts, 39, 40 ... Cylinder bores, 41 ... Double-headed pistons as pistons, 60, 61 ... Compression chambers, 7
8, 79, 107, 108 ... Rotary valve, 80, 8
1, 91, 101, 102 ... Sub-compression chambers, 83, 84 ... Opening passages also serving as discharge passages, 93 ... Electromagnetic valves as opening / closing valves, 95 ... Discharging passages, 109, 110 ... Recesses also serving as discharging passages.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Konomura 2-chome, Toyota-cho, Kariya city, Aichi Stock company Toyota Industries Corp.

Claims (7)

[Claims] 1. A plurality of cylinder bores are arranged around a drive shaft in a cylinder block, a piston is accommodated in the cylinder bore to define a compression chamber, and the piston is interlocked with the rotation of the drive shaft. In a piston type compressor that reciprocates to compress the refrigerant gas, a sub compression chamber communicating with the compression chamber is provided, and an opening / closing valve for opening and closing the sub compression chamber and the compression chamber is provided. A piston-type compressor that has an opening / closing valve that is closed during the intake stroke. 2. The piston type compressor according to claim 1, wherein the on-off valve is opened before the volume in the compression chamber reaches approximately one-half of the time when the compression is started in the compression stroke. 3. The piston type compressor according to claim 2, wherein the on-off valve opens and closes in synchronization with rotation of the drive shaft. 4. The piston type compressor according to claim 3, wherein the on-off valve is a rotary valve supported by the drive shaft so as to be integrally rotatable. 5. The piston type compressor according to claim 4, wherein the sub compression chamber is formed inside the rotary valve. 6. The piston type compressor according to claim 1, further comprising a discharge passage for discharging the refrigerant gas in the sub compression chamber to a predetermined chamber. 7. The piston type compressor according to claim 6, wherein the predetermined chamber is a compression chamber in another compression stroke.