JPH048635B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable capacity compressor, and in particular, the compressor of the present invention is suitable for a refrigerant compressor of an automobile air conditioner. Generally, the refrigerant compressor used in automobile air conditioners rotates under the driving force of the automobile engine, so when the engine is running at high speeds such as when driving at high speed or accelerating, the compressor's temperature is higher than necessary. It was rotating at RPM. Therefore, the cooling capacity of the air conditioner becomes excessive. On the other hand, when the engine is idling, the compressor uses about 30% of the engine output, which puts an excessive load on the engine.
Controlling the cooling capacity becomes complicated and the fuel efficiency of the engine deteriorates. Therefore, the development of compressors that can change the discharge amount of the compressor is underway. SUMMARY OF THE INVENTION An object of the present invention is to provide a compact compressor that can arbitrarily change the discharge amount using a single solenoid valve.

In order to achieve this object, the present invention provides a variable capacity compressor of the present invention with the following configuration. That is, the variable capacity compressor of the present invention divides the discharge chamber that receives discharge from the cylinder into a first discharge chamber and a second discharge chamber, and separates the first discharge chamber and the second discharge chamber from the second discharge chamber to the first discharge chamber. A check valve that allows only fluid to flow into the second discharge chamber and a valve section that opens and closes between the second discharge chamber and the low pressure space (suction chamber) is provided, and a pressure chamber is connected to the second discharge chamber and the low pressure space (suction chamber). and a plunger that opens and closes the valve part by fluid pressure from the first discharge chamber, the first discharge chamber and the pressure chamber are connected by a first fluid passage having a thin communication hole, and the pressure chamber and the low pressure space are connected. Second
They are connected by a fluid passage and are provided with a solenoid valve that opens and closes this second fluid passage.

In the variable displacement compressor of the present invention, the second fluid passage is closed by closing the solenoid valve, the high pressure fluid in the first discharge chamber is kept flowing into the pressure chamber, and the plunger is actuated by the pressure, so that the low pressure space and the second fluid passage are closed. The valve section between the discharge chambers is closed, and the high-pressure fluid flowing into the second discharge chamber is sent to the first discharge chamber through the check valve to perform 100% capacity operation.

On the other hand, if the discharge capacity does not need to be small, the solenoid valve is opened to open the second fluid passage connecting the pressure and low pressure spaces, and the high pressure fluid in the pressure chamber flows out into the low pressure space through the second fluid passage. The drop in pressure operates the plunger to open the valve part, communicates the second discharge chamber with the low-pressure space, and substantially idles the action of the cylinder that discharges to the second discharge chamber, causing high pressure to be discharged to the first discharge chamber. Operate at a low capacity of gas discharge only.

Note that during this low capacity operation, the first fluid passage connecting the first discharge chamber and the pressure chamber is in communication, and high-pressure fluid flows into the pressure chamber through this first fluid passage.
Since the first fluid passage has a narrow communication hole, the amount of high-pressure fluid that flows into the second fluid passage is smaller than the amount of fluid that flows out from the pressure chamber to the low-pressure space due to the inflow resistance of the narrow communication hole. Therefore, even if the fluid pressure in the pressure chamber is initially high, the pressure in the pressure chamber gradually decreases, and during low capacity operation when the plunger operates, a portion of the high pressure fluid in the first discharge chamber is transferred from the first fluid passage to the high pressure chamber to Although the second fluid passage passes through the low-pressure space and is lost, this is an operating condition in which the capacity should be reduced, so there is no problem with the high-pressure fluid flowing out at this time.
During 100% operation, the second fluid passage is closed by the solenoid valve, so once the high-pressure fluid in the first discharge chamber fills the pressure chamber, there is no flow of high-pressure fluid from the first discharge chamber, and the first discharge chamber , 100% of the high pressure fluid discharged into the second discharge chamber is utilized.

In this way, in the variable displacement compressor of the present invention, the first
By providing a narrow communication hole in the fluid passage and providing a solenoid valve in the second fluid passage, it is possible to switch the discharge capacity with one solenoid valve, and no leakage of high-pressure fluid occurs at 100% capacity. This makes it a compact and high-performance variable capacity compressor.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In the figure, reference numeral 1 denotes a rotating shaft, which is connected via an electromagnetic clutch to an automobile engine serving as a driving source, and is rotated by the driving force of the engine. Reference numeral 2 denotes a swash plate made of ferrous metal molded into a circular shape, and is fixed to the rotating shaft 1 with a key so that it swings and rotates together with the rotating shaft 1. This rocking rotation of the swash plate 2 causes the piston 3 to reciprocate through the show ball. 4 is a housing having 5 cylinder parts 41 parallel to the axis around the axis and 10 cylinder parts 41 on the left and right sides that support the reciprocating motion of the piston 3, which is divided into left and right parts in FIG. They are formed by tightly bonding each other through a material. A first side housing 5 and a second side housing 6 are hermetically joined to the left and right sides of the housing 4. First side housing 5
A first valve plate 51 is provided between the housing 4 and the housing 4.
are interposed, and the communication holes 51a and 51b of the first valve plate 51 connect the cylinder portion 41 and the
A first suction chamber 52 and a first discharge 53 formed on the side of the first side housing 5 are connected to each other. The first suction chamber 52 communicates with a low pressure chamber to which refrigerant gas vaporized by an evaporator (not shown) is supplied. The first discharge chamber 53 communicates with a high pressure chamber 7 provided at the center side of the housing 4 . Further, the first side housing 5 and the housing 4 are provided with communication passages 54 and 44 that connect the first discharge 53 and a pressure chamber to be described later. Between the second side housing 6 and the housing 4,
A second valve plate 61 is interposed. The second valve plate 61 has five suction communication holes 61a for suction from the outside, and five discharge communication holes 6 on the inside thereof.
1b, it has a disk shape with a large communication hole 61c connected to the bearing hole 42 of the housing 4 in the center.
Second side housing 6 and second valve plate 6
1, a second suction chamber 62 and a second discharge chamber 63 are formed. The suction communication hole 61a is connected to the second discharge chamber 62, and the discharge communication hole 61b is connected to the second discharge chamber 63.
Opens in the center of the Note that the second discharge chamber 63 communicates with the high pressure chamber 7 via a check valve 71. A cylindrical guide 6a is formed in the center of the second discharge chamber 63 of the second side housing 6, and the guide 6a defines an opening in the center. A plunger 81 of the valve portion 8 is inserted into the recessed portion of the guide 6a. One end into which this plunger 81 is inserted becomes a shallow recess, and the bottom surface of the recess of the guide 6a forms a pressure chamber 87.
form. A protrusion 81b is formed at the center of the other end of the plunger 81. A screw hole 81c is formed in this central portion 81b. Further, a ring-shaped retainer 82 and a discharge valve 83, which are the main bodies of the valve part 8, are inserted into the central convex part 81b of the plunger 81, and a fixing ring 84 which also serves as a spring seat is inserted, and a screw is inserted through a washer 85. It is fixed with a bolt 86 screwed into the hole 81c. The valve portion 8 is movable in the axial direction in which the plunger 81 is guided by the recessed portion of the guide 6a. The figure shows a state in which the valve portion 8 is located on the right side, and in this state, the second discharge chamber 63 communicates with the bearing hole 42 of the housing 4 through the center communication hole 61c of the second valve plate. It also communicates with the cylinder portion 41 through the communication hole 61b of the second valve plate. Contrary to the figure, when the valve part 8 is pushed to the left, the discharge valve 83 of the valve part 8 comes into contact with the second valve plate 61, and the communication holes 61b and 61c are closed. Note that the bearing hole 42 of the housing 4 communicates with the low pressure chamber, and a spring seat 42a is provided here. This spring seat 42a and the fixing ring 84 (second
A spring 43 is installed between the valve portions 8 and 8 in a manner that biases the valve portion 8 in the right direction in the figure.

A solenoid valve 9 is provided at the center of the outside of the second side housing 6, and a recess 9a with one end open is provided along the central axis of the solenoid valve. A guide 91 having a stepped cylindrical recess with one end open is fixed to the bottom surface of the recess 9a. An iron valve train 92 is fitted into the cylindrical recess of this guide 91. A recess 92a is formed at the right end of the valve train 92, and a spring 93 is inserted between the bottom of the guide 91 and the bottom of the recess 92a of the valve train 92.
The valve train 92 is urged to the left in the figure. A stopper 92b made of fluororesin is fixed to the left end of the valve train 92.

On the right side in the figure of the second side housing 6 that closes the opening of the recess a along the central axis of the solenoid valve 9, a protrusion 6a that comes into contact with the stopper 92b of the valve train 92 is formed. A central hole 64 is provided along which the pressure chamber 87 communicates.

Further, the second side housing 6 has a first discharge chamber 5.
A high-pressure gas sub-chamber 65 is formed which communicates with the central hole 64 at 54 and 44, and a first fluid passage 66 communicating from the sub-chamber 65 to the center hole 64 is provided. A portion of the first fluid passage 66 that opens into the center hole 64 is a pore 66a with a diameter of about 0.6 mm. Further, the second side housing 6 has a second suction chamber 62 and a recess 9 along the central axis of the solenoid valve 9.
A second fluid passage 67 is provided that opens to a.

The electromagnetic coil 94 is connected to the valve train 9 concentrically with the valve train 92.
When energized, an electromagnetic coil 94 moves the valve train 92 to the right in the figure against the biasing force of its spring 93. The variable capacity compressor of this embodiment has the above configuration.

In addition, the first discharge chamber 53, the high pressure chamber 7, and the high pressure auxiliary chamber 6
5 and the passage connecting them together form a high pressure space, and the first suction chamber 52, the second suction chamber 62, the low pressure chamber and the passage connecting them form a low pressure space according to this embodiment.

Next, the operation of this compressor will be explained.

When the engine and the rotating shaft 1 are coupled by the electromagnetic clutch, the rotating shaft 1 and the swash plate 2 begin to rotate due to the driving force of the engine. As the swash plate 2 rotates, the piston 3 reciprocates within the cylinder 41. This reciprocation of the piston 3 causes the first suction chamber 52 to
The refrigerant gas flows through the communication hole 5 of the first valve plate 51.
It is sucked into the cylinder 41 from 1a through the suction valve. Next, when the piston 3 moves to the compression process, the suction valve closes the refrigerant gas 51a, and the refrigerant gas in the cylinder part 41 is compressed to a high temperature and high pressure, and the refrigerant gas is compressed to the communication hole 51b of the first valve plate 51 and the discharge gas. It is discharged into the first discharge chamber 53 through a valve. This high-temperature, high-pressure gas enters the high-pressure chamber 7 due to its pressure, and is sent from there to a condenser (not shown) via a discharge passage such as a discharge service valve and a communication pipe.

On the other hand, when a current is applied to the electromagnetic coil 94 of the electromagnetic valve 9 on the second side housing 6 side, the valve train 92 is moved to the right in the figure by the magnetic force and becomes the state shown in the figure. As a result, the pressure chamber 87
The center hole 64 of the side housing 6, the center hole 9a of the electromagnetic valve 9, and the second fluid passage 67 communicate with the second suction chamber (low pressure space). Since the refrigerant gas pressure in the second suction chamber is low, the refrigerant gas pressure in the pressure chamber 87 is also low. Therefore, the plunger 81 of the valve part 8 is
Due to the urging force No. 3, it is pressed to the right side as shown in the figure. Note that since the valve portion 8 is pressed to the right side, the discharge valve 83 of the valve portion is separated from the second valve plate 61. Therefore, the communication hole 61b of the second valve plate 61 always communicates the cylinder 41 and the second discharge chamber 63. Also, the second discharge chamber 63
is the communication hole 61 in the center of the second valve plate 61
c communicates with the bearing hole 42 which communicates with the low pressure chamber. Therefore, compression of the refrigerant gas by the piston 3 and cylinder 41 on the second side housing 6 side does not occur, resulting in an idling state. Note that the high pressure chamber 7 and the second discharge chamber 63 are closed by the check valve 71 and flow into the pressure chamber 87 . However, since the pores 66a of the first fluid passage 66 are very narrow with a diameter of about 0.6 mm, the refrigerant gas flows out from the pressure chamber 87 to the lower pressure space through the second fluid passage 67, which has a diameter of about 2 mm. The amount is much larger than the amount of refrigerant gas flowing in from the first fluid passage. For this reason, the pressure chamber 87
The refrigerant gas pressure is almost equal to the refrigerant gas pressure in the low pressure space, and cannot resist the biasing force of the spring 43.

In this state, only the refrigerant gas discharged into the first discharge chamber 53 is sent to a condenser (not shown), and the system is operated at approximately 50% discharge capacity.

Note that the amount of gas flowing out from the first fluid passage 66 to the low pressure chamber is 3 times the amount of gas discharged into the first discharge chamber 53.
%, but in this state it is in low capacity operation, and no special inconvenience will occur even if 50% capacity operation becomes 48.5% capacity operation. In this state, for example, if the temperature inside the vehicle increases and you want to increase the cooling capacity, turn off the solenoid valve 9 and turn off the solenoid coil 94.
stop the current. As a result, the valve train 92 is activated by the spring 93.
is pressed to the left side in FIG. 2 by the urging force of
a to close the central hole 64 opening at the center of the convex portion 6a. Therefore, communication between the pressure chamber 87 and the second suction chamber 62 is cut off, and gas no longer flows into the first suction chamber 62 from the high pressure chamber 7 . On the other hand, pressure chamber 87
The high pressure gas in the first discharge chamber 53 gradually flows into the first discharge chamber 53 through the narrow hole 66a of the first fluid passage 66. As a result, the refrigerant gas pressure in the pressure chamber 87 increases considerably, and the plunger 81 is finally moved to the left in the figure against the biasing force of the spring 43. As a result, the discharge valve 83 of the valve portion 8 comes into contact with the second valve plate 61. And the valve part 8 is a second valve plate 61
is being forced on. As a result, the discharge valve 83 of the valve portion 8 is connected to the communication hole 61 of the second valve plate 61.
Close b, 61c. Therefore, the piston 3 and cylinder 41 on the second side housing 6 side also start compressing the refrigerant gas, and the refrigerant gas pressure in the second discharge chamber 63 increases. When the pressure becomes higher than the pressure in the pressure chamber 7, the check valve 71 opens, and high temperature, high pressure refrigerant gas flows into the high pressure chamber 7 from the second discharge chamber 63. In this state, the compressor operates at 100% full capacity.

Note that high-pressure refrigerant gas flows into the pressure chamber 87 from the first discharge chamber 53 through the first fluid passage 66, but since the central hole 64 is closed by the stopper 92b of the valve train 92, the pressure chamber 87 When the pressure in the first discharge chamber 53 becomes the same as that in the first discharge chamber 53, no refrigerant gas flows into the pressure chamber 87 after that.

Therefore, the first discharge chamber 53 and the second discharge chamber 63
100% of the high-pressure refrigerant gas flowing into the system is sent to a condenser (not shown), eliminating waste.

In this manner, the variable capacity compressor of this embodiment can be switched between 100% operation and 50% operation by turning one solenoid valve 9 on and off. Since this compressor can change the discharge capacity with a single solenoid valve, the solenoid valve can be incorporated into a part of the compressor, making it extremely compact.
By changing the capacity, excessive operation and high-load operation can be prevented, improving durability and reducing fuel consumption. Particularly, during 100% capacity operation, high-pressure refrigerant gas does not flow out from the solenoid valve 9 into the low-pressure chamber, resulting in high efficiency.

In the embodiment shown in FIGS. 1 and 2, the valve portion 8 is moved away from the second valve plate 61 by the spring 43, but the urging direction of the spring 43 is changed to the opposite direction.
Furthermore, by reversing the movement of the plunger 81 of the valve part 8, the valve part 8 can be pressed against the valve plate, and the valve part 8 can be opened by energizing the solenoid valve. In this case as well, the capacity of the compressor can be changed by turning the solenoid valve on and off, thereby preventing excessive operation and high load operation of the compressor.

In addition, although a swash plate type compressor was used in the example,
The present invention can be applied to a compressor having two or more sets of cylinders and pistons, such as a wobble type compressor having a plurality of discharge valves on one side of a single valve plate.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the compressor of the present invention, and FIG. 2 is an enlarged view of the valve portion shown in FIG. 1. 1... Rotating shaft, 2... Swash plate, 3... Piston,
41... Cylinder part, 53... First discharge chamber, 63
...Second discharge chamber, 66...First fluid passage, 67...
...Second fluid passage, 7...High pressure chamber, 8...Valve section, 8
7...Pressure chamber, 9...Solenoid valve.

Claims (1)

[Claims] 1. It has a plurality of pistons and a plurality of cylinders that support the reciprocating motion of each piston, and also includes a low pressure space, a first discharge chamber that receives discharge from some cylinders, and other cylinders. a housing having a second discharge chamber that receives discharge from the housing; and a non-return check that is interposed between the first discharge chamber and the second discharge chamber and allows only fluid to flow from the second discharge chamber to the first discharge chamber. a valve, a valve part that opens and closes the second discharge chamber and the low pressure space, and a plunger that is coupled to the valve part and has a pressure chamber inside and opens and closes the valve part by fluid pressure from the first discharge chamber. a first fluid passageway having a thin communication hole connecting the first discharge chamber and the pressure chamber; a second fluid passageway connecting the pressure chamber and the low-pressure space; and an electromagnetic fluid passageway for opening and closing the second fluid passageway. A variable displacement compressor characterized by comprising a valve. 2 The diameter of the thin communication hole of the first fluid passage is 0.3 mm ~
1.2 mm, and the diameter of the second fluid passage is 1.2 times or more the diameter of the thin communication hole.
Compressor as described in section.