JP3510659B2 - Thrust direction compliance mechanism of scroll compressor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thrust direction compliance mechanism of a scroll compressor in which a scroll portion of a fixed scroll and a scroll portion of an orbiting scroll are arranged so as to face each other.

[0002]

2. Description of the Related Art A thrust direction compliance mechanism of a scroll compressor in which a scroll portion of a fixed scroll and a scroll portion of an orbiting scroll are arranged so as to mesh with each other is disclosed in, for example, JP-A-53-119.
No. 412 or Japanese Patent Laid-Open No. 58-128485, "Scroll Compressor".

[0003]

In the thrust direction compliance mechanism for pressing the orbiting scroll against the fixed scroll, when a high pressure is used for the back pressure, the sealing force of the compression portion fluctuates greatly due to the differential pressure between the high pressure and the low pressure. There is a problem that it ends up. Then, the above-mentioned Japanese Patent Laid-Open No. 53-119.
When an intermediate pressure is used as in the scroll compressor disclosed in Japanese Patent No. 412 or Japanese Patent Laid-Open No. 58-128485, the back pressure area is large, and it is possible to flexibly cope with pressure fluctuation due to the characteristics of the intermediate pressure. When using high pressure, the back pressure area must be designed to be small, and when the compression ratio is small (the differential pressure is small), the high pressure is lower than the low pressure and overcompression occurs in the intermediate compression chamber. However, there is a problem that the sealing force is insufficient and gas leakage occurs, resulting in a decrease in capacity. Also, when the compression ratio is large (the differential pressure is large), a high pressure which is considerably higher than a low pressure acts on a predetermined area. However, there is a problem that the pressing force (sealing force) due to the back pressure becomes excessive and the input increases.

[0004]

In order to solve the above problems, the present invention provides, as a first invention, a scroll portion of a fixed scroll and a scroll portion of an orbiting scroll which are arranged to face each other so as to mesh with each other. In the installed scroll compressor, the thrust direction compliance mechanism that presses the orbiting scroll against the fixed scroll has separate closed spaces, which are a first back pressure chamber and a second back pressure chamber, on the back surface of the orbiting scroll. The first back pressure chamber is constantly supplied with high pressure gas, and the second back pressure chamber is supplied with either high pressure gas or low pressure gas. A second aspect of the present invention is to provide a compliance mechanism, and the gas supplied to the second back pressure chamber of the first invention is a differential pressure operated valve using a spring and an operating valve body. Accordingly it is intended to provide a thrust direction compliance mechanism of the scroll compressor adapted to be changed over to either the high pressure gas or a low pressure gas.

[0005]

Under a wide range of pressure conditions, it is impossible to maintain a proper sealing force by applying a high pressure to the back pressure chamber having a certain area and pressing the orbiting scroll to the fixed scroll side. Therefore, by switching the back pressure area where high pressure acts in accordance with the pressure condition, it is possible to provide a proper sealing force in a wide range of pressure conditions. Therefore, first, a first back pressure chamber and a second back pressure chamber are formed on the back surface of the orbiting scroll,
High pressure is constantly applied to the first back pressure chamber, and high pressure gas is supplied to the second back pressure chamber when the differential pressure is small due to low speed operation, and when the differential pressure is large due to high speed operation. The supply pressure is switched so that the low-pressure gas is supplied.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the thrust direction compliance mechanism of the scroll compressor according to the present invention will be described below with reference to FIGS.
This will be described with reference to FIG. 1 is a vertical sectional front view showing a first embodiment of a scroll compressor having a thrust direction compliance mechanism according to the present invention, and FIG.
3A and 3B show the thrust direction compliance mechanism of the scroll compressor of FIG. 3A is an explanatory view when the pressure difference between high and low pressures is small, and FIG. 3B is an explanatory diagram when the pressure difference between high and low pressures is large, and FIG. FIG. 4 is a vertical sectional front view showing a second embodiment of a scroll compressor incorporating a thrust direction compliance mechanism, and FIG. 4 shows the thrust direction compliance mechanism of the scroll compressor of FIG.
(A) is an explanatory view when the high and low pressure difference is small, (B) is an explanatory view when the high and low pressure difference is large, (C) is an upper view of the differential pressure actuated valve of (A) and (B).

First Embodiment The thrust direction compliance mechanism of the scroll compressor according to the first embodiment is, as shown in FIGS. 1 and 2,
A scroll compressor in which the scroll portion of the fixed scroll 1 and the scroll portion of the orbiting scroll 2 are arranged to face each other so as to mesh with each other. The first seal ring 3 and the second seal ring 4 are doubly installed on the back surface of the to form the double seal chamber 5, and the first back pressure chamber (the closed space formed by the first seal ring 3) and Second back pressure chamber (first seal ring 3 and second
Separate sealed space), which is a closed space formed by the seal ring 4 of FIG. 1, and high pressure gas is constantly supplied to the first back pressure chamber to provide a pressing force for the orbiting scroll 2. When the differential pressure is small, the back pressure chamber of
As shown in (A), the high pressure gas is supplied through the pressure supply port 6,
The back pressure area is increased to increase the pressing force. When the differential pressure is large, low pressure gas is supplied through the pressure supply port 6 as shown in FIG. Try to reduce the force. In this case, the pressure gas supplied is switched by solenoid valves 7 and 8 outside the compressor.

Second Embodiment The thrust direction compliance mechanism of the scroll compressor according to the second embodiment is as shown in FIGS.
The scroll portion of the fixed scroll 21 and the orbiting scroll 2
In the scroll compressor arranged so as to face each other so that the two scroll portions mesh with each other, the orbiting scroll 22
Is pressed against the fixed scroll 21, and the first seal ring 23 and the second seal ring 24 are doubly installed on the back surface of the orbiting scroll 22 to form the double seal chamber 2.
5 is formed, the first back pressure chamber (the first seal ring 23
And a second back pressure chamber (a closed space formed by the first seal ring 23 and the second seal ring 24), and separate sealed spaces are formed in the first back pressure chamber. The high pressure gas is constantly supplied, and the gas supplied to the second back pressure chamber is switched by the differential pressure operation valve 26 using the spring 27 and the operation valve body 28. The differential pressure actuated valve 26 shown in FIG. 3 is a valve that can be automatically switched by the spring 27 and the actuated valve body 28 inside the compressor, but when the low pressure + spring force> high pressure, that is, when the differential pressure is small, the first Seal ring 23 and second
A high pressure acts on the space between the first seal ring 23 and the second seal ring 24 when a low pressure + spring force <high pressure, that is, when the differential pressure is large. Low pressure acts on. For switching between high pressure and low pressure, an appropriate value of the sealing force can be obtained by arbitrarily setting the spring constant. 29 is a stop pin.

[0009]

Since the thrust direction compliance mechanism of the scroll compressor of the type in which the oscillating scroll is pressed against the fixed scroll is constructed as described above, the back pressure area can be arbitrarily switched to cover a wide range of pressure conditions. It is possible to maintain an appropriate sealing force.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing a first embodiment of a scroll compressor according to the present invention.

2A and 2B show a thrust direction compliance mechanism of the scroll compressor shown in FIG. 1, where FIG. 2A is an explanatory diagram when a pressure difference between high and low pressures is small, and FIG. 2B is an explanatory diagram when a pressure difference between high and low pressures is large.

FIG. 3 is a vertical sectional front view showing a second embodiment of the scroll compressor according to the present invention.

4A and 4B show a thrust direction compliance mechanism of the scroll compressor shown in FIG. 3, in which FIG. 4A is an explanatory view when the height difference is small, FIG. 4B is an explanatory view when the height difference is large, and FIG. 8A is a top view of the differential pressure actuated valve of FIGS.

[Explanation of symbols]

1: Fixed scroll 2: Swing scroll 3: First seal ring 4: Second seal ring 5: Double sealed room 6: Pressure supply port 7, 8: Solenoid valve 21: Fixed scroll 22: Swing scroll 23: First seal ring 24: Second seal ring 25: Double sealed room 26: Differential pressure operated valve

Claims (2)

(57) [Claims] 1. A thrust direction compliance mechanism for pressing the orbiting scroll against the fixed scroll in a scroll compressor in which the scroll portion of the fixed scroll and the scroll portion of the orbiting scroll are arranged to face each other so as to mesh with each other. Separate closed spaces serving as a first back pressure chamber and a second back pressure chamber are formed on the back surface of the orbiting scroll, and high pressure gas is constantly supplied to the first back pressure chamber, and the second back pressure chamber is supplied with the second back pressure chamber. A thrust direction compliance mechanism for a scroll compressor, wherein either high pressure gas or low pressure gas is supplied to the back pressure chamber. 2. A thrust direction compliance mechanism for pressing the orbiting scroll against the fixed scroll in a scroll compressor in which the scroll portion of the fixed scroll and the scroll portion of the orbiting scroll are arranged so as to face each other so as to mesh with each other. Separate closed spaces serving as a first back pressure chamber and a second back pressure chamber are formed on the back surface of the orbiting scroll, and high pressure gas is constantly supplied to the first back pressure chamber, and the second back pressure chamber is supplied with the second back pressure chamber. The gas supplied to the back pressure chamber is switched to either a high pressure gas or a low pressure gas by a differential pressure operating valve using a spring and an operating valve body, and the thrust of a scroll compressor is characterized. Directional compliance mechanism.