JPS58195089A - Variable displacement compressor - Google Patents

Abstract

PURPOSE:To change a delivery amount through selective operation of a single solenoid valve, by dividing a delivery chamber into two chambers, providing a check valve between the both chambers, opening and closing a valve part between one of the delivery chambers and a suction chamber, providing a plunger opening and closing the valve part through fluid pressure of the other one of the delivery chambers to the valve part and interposing the solenoid valve between the chambers. CONSTITUTION:If a piston 3 performs reciprocating motion in a cylinder 41, coolant gas flowing into the cylinder 41 from the first suction chamber 52 flows into a high pressure chamber 7 via the first delivery chamber 53 and is fed to a condenser. Here if an electric current is conducted to flow in a coil 91 of a sol- enoid valve 9, a communication hole 61b of the first valve plate 61 always communicates the cylinder 41 and the second delivery chamber 63, while the chamber 63, being communicated to a bearing hole 42 communicated to a low pressure chamber by a communication hole 61c, causes no compression of gas by the cylinder 41 to become an idle condition. Under this condition, only the coolant gas delivered to the chamber 53 is delivered to obtain 50% displacement operation.

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 conditioning systems rotates under the driving force of the engine for automatic driving, so the compressor is necessary in operating conditions where one engine rotates, such as during high-speed driving or acceleration during automatic driving. It was rotating at a higher RPM. Therefore, the cooling capacity of the air conditioner becomes excessive. Conversely, when the engine is idling, the compressor uses about 30% of the engine output4.
This puts an excessive load on the engine, making it difficult to control the cooling capacity and worsening the engine's fuel efficiency. Therefore, the development of compressors that can change the discharge sound 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 volume 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 is provided to allow only fluid to flow into the second discharge chamber, and the second discharge chamber and the low pressure space (
A valve part is provided to open and close between the first discharge chamber and a plunger which is connected to the face part and has a pressure chamber therein, and which opens and closes the valve part by fluid pressure from 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 by a second fluid passage.
It is equipped with a solenoid valve that opens and closes fluid and passages.

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 part 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.
Perform % 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 plunger is actuated by the drop in pressure to open the valve part, communicate the second discharge chamber with the low pressure space, and substantially idle the action of the cylinder to discharge the high pressure 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 communication hole is provided, 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 through the second fluid passage because the inflow of the narrow communication hole is strictly restricted. For this reason, even if the fluid pressure in the pressure chamber is initially high, the pressure in the pressure chamber gradually decreases and the plunger operates.During low capacity operation, a portion of the high pressure fluid in the first discharge chamber is transferred from the first fluid passage to the high pressure chamber. Although the second fluid passage passes through the low-pressure space and is lost, this is an operating state 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 capacity compressor of the present invention, by providing a thin communication hole in the first 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 the discharge capacity can be changed 100%. No leakage of high pressure fluid occurs at 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 to an automobile engine serving as a driving source via an electromagnetic clutch, and is rotated by the driving force of the engine. Reference numeral 2 denotes a swash plate made of ferrous metal molded into an oval 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 shoe ball. Reference numeral 4 denotes a housing having cylinder parts 41 that support the reciprocating motion of the piston 3, five in parallel with the axis around the axis, and ten on the left and right, and is divided into left and right parts in Fig. 1 and die cast. It is formed by closely bonding through the. A first side housing 5 and a second side housing 6 are hermetically joined to the left and right sides of the housing 4. A first valve plate 51 is interposed between the first side housing 5 and the housing 4, and the communication hole 5 of this first valve plate 51
1a and 51b, the cylinder part 41, the first suction chamber 52 and the first discharge chamber 5 formed on the first side housing 5 side
3 will be contacted. 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 . In addition, the first side housing 5
A communication passage 54.44 is provided in the housing 4 and connects the first discharge chamber 53 and a pressure chamber to be described later.

Between the second side housing 6 and the housing 4, a second
A valve plate 61 is interposed. The second valve plate 61 has five suction holes 61a for suction from the outside,
It has a disc shape with five discharge communication holes 61b on the inside and a large communication hole 61c connected to the bearing hole 42 of the housing 4 in the center.

A second suction chamber 62 and a second discharge chamber 63 are formed between the second side housing 6 and the second valve plate 61. The suction passage hole 61a opens into the second discharge chamber 62, and the discharge passage hole 61b opens into the center of the second discharge chamber 63. 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 the plunger 81 is inserted becomes a shallow recess, and a pressure chamber 87 is formed and covered by the bottom surface of the recess of the guide 6a. 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 that surround the main body of the valve portion 8 are inserted into the central convex portion 81b of the plunger 81, and a fixing ring 84 that also serves as a spring seat is inserted, and screwed 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 with a plunger 81 being guided by a recessed portion of the guide 6a. The figure shows a state in which the valve part 8 is located on the right side, and in this state, the second discharge chamber 63 passes through the center communication hole 61c of the second valve plate and into the bearing hole 4 of the housing 4.
2 and also communicates with the cylinder portion 41 through the communication hole 61b of the second valve plate. Contrary to the diagram, valve part 8
When pressed to the left, the discharge valve 83 of the valve portion 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 of the valve part 8
(FIG. 2), a spring 43 is installed in a state that biases the valve portion 8 rightward 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. to strengthen A stopper 92 made of fluororesin is attached to the left end of the valve train 92.
b is fixed.

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

Further, a high-pressure gas sub-chamber 65 is formed in the second side housing 6 and communicates with the first discharge chamber 53 at 54.44, and a first fluid passage 6 communicates from the sub-chamber 65 to the center hole 64.
6 is provided. The center hole 6 of this first fluid passage 66
The passageway opening into 4 is a pore 6 with a diameter of about 0.6 mm.
6a What's going on? Furthermore, the second side housing 6 opens into a second suction chamber 62 and a recess 9a along the central axis of the solenoid valve 9. A second fluid passage 67 is provided.

The electromagnetic coil 94 is provided around the valve actuator 92 concentrically with the valve actuator 92, and when energized, the electromagnetic coil 94 moves around the valve actuator 92.
2 does not move to the right in the figure against the biasing force of the spring 93.

The variable capacity compressor of this embodiment has the above configuration.

Note that a high-pressure space is formed by the first discharge chamber 53, the high-pressure chamber 7, the high-pressure auxiliary chamber 65, and the passage connecting them, and the first suction chamber 5
2. The low pressure space according to this embodiment is formed by the second suction chamber 62, the low pressure chamber, and the passage connecting these.

Next, the operation of this single compressor will be explained.

When the engine and the rotating shaft 1 are connected 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 cylinder 41
The piston 3 reciprocates inside.

By this reciprocation of the piston 3, the refrigerant gas in the first suction chamber 52 is sucked into the cylinder 41 through the communication hole 51a of the first valve plate 51, through the suction valve.

Next, when the piston 3 moves to the compression process, the suction valve 51a is closed, and the refrigerant gas in the cylinder part 41 is
It is compressed to high temperature and high pressure, and the first valve plate 51
It is discharged into the first discharge chamber 53 through the communication hole 51b and the discharge valve. This high-temperature, high-pressure gas flows into the high-pressure chamber 7 due to its pressure.
From there, it is sent 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 signal 6 side, the valve operating valve 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 communicates with the second suction chamber (low pressure space) through the center hole 64 of the second side housing 6, the center hole 9a of the electromagnetic valve 9, and the second fluid passage 67. 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 portion 8 is pressed to the right side in the figure by the biasing force of the spring 43.

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 between the cylinder 41 and the 211th outlet chamber 63. Also second
The discharge chamber 63 communicates with the bearing hole 42, which communicates with the low pressure chamber, through a communication hole 61C in the center of the second valve plate 61. Therefore, the refrigerant gas is not compressed by the piston 3 and cylinder 41 on the second side housing 6 side, and an idle state occurs. 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, the diameter of the pore 66a of this first fluid passage 66 is about 0.6
Since the refrigerant gas is very thin (approximately 2 mm in diameter), the amount of refrigerant gas flowing out from the pressure chamber 87 into the low pressure space through the second fluid passage 67, which has a diameter of approximately 2 mm, is compared to the amount of refrigerant gas flowing in from the first fluid passage. Much more. Therefore, the refrigerant gas pressure in the pressure chamber 87 is approximately equal to the refrigerant gas pressure in the low pressure space, and the spring 43
cannot resist the urging force of

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 about 3% of the amount of gas discharged into the first discharge chamber 53, but in this state, the low volume layer is operating, and the volume is reduced to 50%. Even if the operation becomes 48.5% capacity operation, no special inconvenience will occur. In this state, for example, if the temperature inside the vehicle increases and the cooling capacity is desired to be increased, the solenoid valve 9 is switched off and the current flowing through the electromagnetic coil 94 is stopped. As a result, the valve actuator 92 is pressed to the left side in FIG. 2 by the biasing force of the spring 93, and the fluororesin stopper 92b is pressed against the convex portion 6a of the central hole 64, and the central hole opening in the center of the convex portion 6a is pressed. Close 64. 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, in the pressure science 87, the pore 66 of the first fluid passage 66
The high pressure gas in the first discharge chamber 53 gradually flows through the narrow hole a. As a result, the refrigerant gas pressure in the pressure chamber 87 gradually increases, and finally the first langier 81 moves to the side 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. The valve portion 8 is pressed against the second valve plate 61. As a result, the discharge valve 83 of the valve portion 8 closes the communication holes 61b and 61c of the second valve plate 61. 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, 100% of the high-pressure refrigerant gas flowing into the first discharge chamber 53 and the second discharge chamber 63 is sent to a condenser (not shown), so that no waste occurs.

In this way, the variable capacity compressor of this embodiment has one solenoid valve 9.
You can switch between 100% operation and 50% operation by turning 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 into the low-pressure chamber through the solenoid valve 9, resulting in high efficiency.

However, by reversing the biasing direction of the spring 43 and reversing the movement of the plunger 81 of the valve part 8, the valve part 8 is moved away from the second valve plate 61. It is also possible to press the valve portion 8 against the plate and open the valve portion 8 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, it is also suitable for compressors with two or more sets of cylinders and pistons, such as a wobble type compressor with multiple discharge valves on one side of a single valve plate. The invention can be applied.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of an embodiment of the compressor of the present invention;
The figure is an enlarged view of the valve section shown in FIG. 1.

Claims (2)

[Claims] (1) It has a plurality of pistons and a plurality of cylinders that support the reciprocating motion of each piston, and has a low-pressure space, a first discharge chamber that receives discharge from some cylinders, and a first discharge chamber that receives discharge from other cylinders. a housing that covers and receives a second discharge chamber; a check valve 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 portion that opens and closes the second discharge chamber and the low pressure space; a plunger that is coupled to the valve portion and has a pressure chamber therein and that opens and closes the valve portion by fluid pressure from the first discharge chamber; a first fluid passage having a thin communication hole connecting the first discharge chamber and the pressure chamber; a second fluid passage connecting the pressure chamber and the low pressure space; and a solenoid valve that opens and closes the second fluid passage. A variable capacity compressor characterized by: (2) The diameter of the narrow 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 less the diameter of the narrow communication hole.