JPH03260378A - Variable displacement swash plate type compressor - Google Patents

Abstract

PURPOSE:To improve volume variable responsiveness by providing a communication path, which connects a delivery chamber to a crank chamber, and interposing a control means for opening/closing this communication path in its halfway. CONSTITUTION:A cylinder block 10, in which a plurality of cylinders 11 are provided in the peripheral direction, is formed integrally with a casing main unit 2, and one end part of a piston rod 58 of a piston 57, fitted to each cylinder 11, is support-engaged with a swing plate 48 swingable along a swash plate 40. A connection chamber 64 is formed in the cylinder block 10, and a crank chamber 4 is connected to a suction chamber 17 through the first communication path 67 contained with this connection chamber 64. A bellows 71 for driving a needle valve 72 is housed in the connection chamber 64. In a compressor thus obtained, a pipe 75(second communication path), which connects its one end to a delivery chamber 16 and another end to the crank chamber 4, is provided, and an electromagnetic valve 76, opened when the delivery volume is reduced, is interposed halfway the pipe 75.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a variable capacity swash plate compressor.

[Prior Art] FIG. 2 is a sectional view of an example of a conventional variable capacity swash plate compressor.

Referring to FIG. 2, the conventional variable capacity swash plate compressor is as follows:
A casing 1 having a crank chamber 4, a cylinder block 10 having a cylinder 11 and provided in the casing 1, and a cylinder block 1 having a suction chamber 17 and a discharge chamber 16.
0, a main shaft 30 rotatably arranged in the crank chamber 4, and a main shaft 3
0, and a swash plate 40 that is attached to the main shaft 30 and rotatably connected to one end of the rotor 38.
, a rocking plate 48 rotatably provided on the swash plate 40 , a piston 57 slidably inserted into the cylinder 11 and connected to the rocking plate 48 , and connecting the crank chamber 4 and the suction chamber 17 . A first communication passage 67 that communicates with the first communication passage 67, a first control means 72 that controls opening and closing of the first communication passage 67, and a first control means 72 that detects the pressure in the crank chamber 4 and controls the first communication passage 67. (See, for example, Japanese Patent Laid-Open No. 87679/1983).

In the case of conventional variable capacity swash plate compressors, when the pressure in the crank chamber increases, the angle of inclination of the swash plate with respect to the main axis decreases, reducing the discharge capacity of the compressor, and conversely, the pressure in the crank chamber increases. When the height is lowered, the angle of inclination of the swash plate with respect to the main axis becomes larger, and the discharge capacity of the compressor becomes larger.

The pressure in the crank chamber is determined by the flow rate of blow-by gas leaking into the crank chamber from between the cylinder and the piston and the flow rate of blow-by gas in the crank chamber returning to the suction chamber through the first communication path. Therefore, by controlling the opening and closing of the first communication passage by the first control means, the pressure in the crank chamber is controlled, and as a result, the discharge capacity of the compressor is also controlled.

[Problems to be Solved by the Invention] In the case of a conventional variable capacity swash plate compressor, when the first communication passage is opened by the first control means, the blow-by gas in the crank chamber flows out to the suction chamber, and the crank is immediately turned off. The pressure in the room decreases and the discharge capacity of the compressor increases.

However, even if the first communication passage is closed by the first control means in order to reduce the discharge capacity of the compressor, blow-by gas accumulates in the crank chamber, and it takes time for the pressure in the crank chamber to actually increase. Ta. Therefore, the conventional variable capacity swash plate compressor has the disadvantage that it takes time for the discharge capacity to actually decrease after the first control means is closed, resulting in poor responsiveness.

Therefore, an object of the present invention is to provide a variable capacity swash plate compressor with good responsiveness when reducing the discharge capacity.

[Means for Solving the Problems] According to the present invention, a casing having a crank chamber, a cylinder block having a cylinder and provided in the casing, and a suction chamber and a discharge chamber facing the cylinder block. a cylinder head fixed to the main shaft, a main shaft rotatably disposed within the crank chamber, a rotor attached to the main shaft, and a swash plate attached to the main shaft and rotatably connected to one end of the rotor. , a rocking plate rotatably provided on the swash plate, a piston slidably inserted into the cylinder and connected to the rocking plate, and communicating the crank chamber and the suction chamber. a first communication path;
A variable capacity type comprising a first control means for controlling opening and closing of the first communication passage, and a detection means for detecting the pressure in the crank chamber and causing the first control means to open and close the first communication passage. A variable capacity swash plate compressor, comprising: a second communication passage that communicates the discharge chamber with the crank chamber; and second control means for controlling opening and closing of the second communication passage. A type swash plate compressor is obtained.

[Function] The variable capacity swash plate compressor of the present invention is equipped with a second communication passage that communicates the discharge chamber and the crank chamber, and a second control that controls opening and closing of the second communication passage. Since the means is provided, when reducing the discharge capacity, by opening the second control means, the gas in the discharge chamber flows into the crank chamber through the second communication path, and this gas immediately reduces the pressure in the crank chamber. This immediately reduces the discharge capacity.

[Embodiment Figure 1 shows a variable capacity swash plate type pressure m according to an embodiment of the present invention.
FIG.

Referring to FIG. 1, a casing 1 includes a casing main body 2
and a front end plate 3 that closes one open end of the casing body 2.

A crank chamber 4 is configured within the casing 1.

The cylinder block 10 has a plurality of cylinders 11. The cylinder 11 is arranged so as to surround a main shaft 30, which will be described later. This cylinder block 10 is formed integrally with the casing body 2, but of course the cylinder block and the casing body may be separate bodies.

The cylinder head 15 has a discharge chamber 16 in its center, and also has a suction chamber 17 formed to surround the discharge chamber 16. The cylinder head 15 also includes a suction port 18 communicating with the suction chamber 17 and a discharge chamber 16.
It has a discharge port, port 19, which passes through.

The cylinder head 15 is fixed to the casing body 2 with a valve plate device 20 interposed between the cylinder block 10 and the cylinder block 10 .

The valve plate device 20 includes a valve plate 21, a suction valve (not shown) disposed on the cylinder block 10 side of the valve plate 21, and a discharge valve (not shown) disposed on the cylinder head 15 side of the valve plate 21. A valve retainer 22 is provided to prevent the discharge valve from opening too much. The valve plate 21 is provided with a suction hole 23 and a discharge hole 24 . The suction hole 23 communicates the suction chamber 17 and the cylinder 11, and is opened and closed by a suction valve. The discharge hole 24 is connected to the cylinder 11 and the discharge chamber 16.
It is opened and closed by a discharge valve.

The main shaft 30 is rotatably arranged in the crank chamber 4, with one end supported by a ball bearing 31 provided in the front end plate 3 and the other end supported by a ball bearing 32 provided in the cylinder block 10. ing.

The rotor 38 is attached to the main shaft 30.

A needle bearing 39 is provided between the rotor 38 and the front end plate 3.

The swash plate 40 is attached to the main shaft 30 through a spherical pusher L41 that is slidably provided on the main shaft 301''.The swash plate 40 is connected to the rotor 3 through a hinge mechanism 42.
It is rotatably connected to one end of 8.

The swing plate 48 is rotatably provided on the swash plate 40 with needle bearings 49, 50 interposed therebetween. Swing plate 48
A portion of the guide rod 51 slidably holds a guide rod 51 disposed in the crank chamber 4 in parallel with the main shaft 30 . This allows the swing plate 48 to swing without rotating (rotating).

The piston 57 is slidably inserted into each cylinder 11, respectively. Each piston 57 is connected to the rocking plate 48 via a piston rod 58, respectively. Therefore, each piston 57 is configured to reciprocate within the cylinder 11 by the swinging of the swinging plate 48.

A connection chamber 64 is provided in the cylinder block 10 . Further, the cylinder block 10 is provided with a first communication hole 65 that communicates with the connection chamber 64 and the crank chamber 4 . Therefore, the pressure in the connection chamber 64 becomes equal to the pressure in the crank chamber 4. Furthermore, a valve plate bag! 20 is provided with a second communication hole 66 that communicates the connection chamber 64 and the suction chamber 17. The above-described first communication hole 65, connection chamber 64, and second communication hole 66 constitute a first communication path 67 that communicates the crank chamber 4 and the suction chamber 17.

A pedestal 70 is formed in the connection chamber 64.

A bellows 71 is attached to the base 70.

A needle valve 72 is provided at one end of the bellows 71 in correspondence with the second communication hole 66 .

The second communication hole 66 is opened and closed by the needle valve 72. Therefore, the needle valve 72 serves as a first opening/closing means for controlling opening/closing of the first communicating path 67. Further, the bellows 7] serves as a detection means that causes the needle valve 72 to open and close the first communication passage 67 by detecting the pressure in the crank chamber 4 and expanding and contracting.

One end of the vibrator 75 passes through the discharge chamber 16, and the other end communicates with the crank chamber 4. With this vibrator 75, the discharge chamber 1
A second communication path is configured to communicate between the crank chamber 6 and the crank chamber 4.

The vibrator 75 is equipped with a solenoid valve 76 as a second control means. This solenoid valve 76 controls opening and closing of the second communication path. Therefore, when the solenoid valve 76 is opened, the discharge chamber 16
The gas inside flows into the crank chamber 4, increasing the pressure inside the crank chamber 4, and as a result, the discharge capacity of the compressor immediately decreases.

Note that the second communication path may be formed in the cylinder block 10, and the second control means is not limited to a solenoid valve, but may be a throttle valve or the like.

[Effects of the Invention] The variable capacity swash plate compressor according to the present invention is provided with a second communication passage that communicates the discharge chamber and the crank chamber, and a second communication passage that controls opening and closing of the second communication passage. Since the control means is provided, when reducing the discharge capacity, by opening the second control means, the gas in the discharge chamber flows into the crank chamber through the second communication path, and this gas increases the pressure in the crank chamber. Therefore, the variable capacity swash plate compressor according to the present invention has excellent responsiveness.

FIG. 1 is a sectional view of a variable capacity swash plate compressor according to an embodiment of the present invention, and FIG. 2 is a sectional view of an example of a conventional variable capacity swash plate compressor.

1...Casing, 2...Casing body, 3...
・Front end plate, 4...Crank chamber, 10
...Cylinder block, 11...Cylinder, 15.
...Cylinder head, 16...Discharge chamber, 17...Suction chamber, 18...Suction port, 19...Discharge boat,
20...Valve plate device, 21...Valve plate, 22...Valve retainer, 23...Suction hole, 24...Discharge hole, 3
0...Main shaft, 31.32...Ball bearing, 3
8... Rotor, 39... Two dollar bearing, 40...
... Swash plate, 41 ... Spherical bush, 42 ... Hinge mechanism, 48 ... Rocking plate, 49, 50 ... Needle bearing, 51 ... Guide rod, 57 ... Piston,
58... Piston rod, 64... Connection chamber, 65...
...First communication hole, 66...Second communication hole, 67...
- First communication path, 70... Pedestal, 71... Bellows, 72... Needle valve, 75... Vibrator, 76...
・Electric

[Brief explanation of drawings]

589-

Claims (1)

[Claims] 1. A casing having a crank chamber, a cylinder block having a cylinder and provided in the casing, a cylinder head having a suction chamber and a discharge chamber and fixed opposite to the cylinder block, and a rotating cylinder in the crank chamber. a main shaft arranged such that the main shaft is movable, a rotor attached to the main shaft, a swash plate attached to the main shaft and rotatably connected to one end of the rotor, and a oscillator rotatably provided on the swash plate. a moving plate, a piston slidably inserted into the cylinder and connected to the rocking plate, a first communication passage communicating between the crank chamber and the suction chamber, and the first communication passage. A variable capacity swash plate compressor comprising a first control means for controlling opening and closing, and a detection means for detecting the pressure in the crank chamber and causing the first control means to open and close the first communication passage, A second communication passage that communicates the discharge chamber and the crank chamber, and a second communication passage that controls opening and closing of the second communication passage.
A variable capacity swash plate compressor characterized by comprising a control means.