JPS60162093A - Scroll fluid machinery - Google Patents

Abstract

PURPOSE:To reduce the load on starting a scroll compressor by installing, onto a fixed scroll, a valve apparatus through which fluid is released from a compression space close to the center to the space close to the outer periphery when the pressure in the compression space close to the center becomes higher than the discharge pressure. CONSTITUTION:The captioned scroll compressor is equipped with a valve apparatus 8 for releasing the gas in a compression space 6 close to the center into a compression space 7 close to the outer periphery, onto a scroll 2. Therefore, when the pressure in the compression space 6 increases larger than that in an upper space 4a, a valve piece 10 is pushed-up by the differential pressure, and the compression space 6 communicates to the compression space 7, and the load can be reduced on starting, etc., where the pressure in the upper space 4a is low.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a scroll fluid machine, and particularly to a structure for reducing load at startup.

[Background of the invention]

A scroll compressor will be described as an example of a conventional scroll fluid machine with reference to FIG.

The orbiting scroll 1 consists of an end plate 1a and a thinly wound wrap 1b standing upright on the end plate 1a. Further, the back surface of the mirror plate 1a has a rotation bearing 1C and a rotation prevention mechanism (not shown). Like the orbiting scroll 1, the fixed scroll 2 consists of an end plate 2a and a thinly wound wrap 2b standing upright on the end plate 2a.
An inlet 2C is provided on the outer periphery of the end plate 2a, and an outlet 2d is provided in the center.
and have each.

The orbiting scroll 1 and the fixed scroll 2 are combined with their laps facing inward, and the orbiting scroll 1 is held between the fixed scroll 2 and the frame 3. Reference numeral 4 denotes a casing having a discharge pipe 5, which communicates with the upper space 4aVi and the discharge port 2d, and is normally maintained on the lower discharge side.

In the scroll compressor described above, when the orbiting scroll 1 is caused to orbit (revolution) without rotating, the volume of the space formed by the end plates and wraps of the orbiting scroll 1 and fixed scroll 2 decreases as it moves toward the center of the scroll. The gas sucked through the suction port 2C is compressed and discharged from the discharge port 2d. That is, the gas trapped at the outer periphery of the wrap is compressed toward the center to a constant volume ratio. In the case of a normal air conditioner compressor, this volume ratio is set to about 2.5 to 4 (in the case of fluorocarbons, the pressure ratio is 3 to 5), and the gas in the inhaled state is compressed to a predetermined pressure. do.

By the way, in the earth shrinking machine for an air conditioner, suction pressure and discharge pressure are balanced while the air conditioner is stopped, and this balance pressure is two to three times the normal suction pressure.

However, when the compressor is started in this state, the pressure in the compression space becomes two to three times higher than in the case of normal compression because the gas is compressed to a certain volume as described above. In other words, the load at startup increases, and in some cases, startup may become impossible.

[Purpose of the invention]

An object of the present invention is to provide a scroll fluid machine that can reduce the load during startup by releasing the pressure in the compression space from the Shimada side to the low pressure side during startup.

[Summary of the invention]

In the present invention, the fixed scroll is provided with a valve device capable of releasing the fluid in the air condenser near the center into the space If4 near the outer periphery, so that the fluid between the air compressors near the center is lower than the discharge pressure. When the pressure rises, the differential pressure opens the valve device to release the fluid between the central compressors 9 to the outer peripheral compressors,
This reduces the load required at startup.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIGS. 2 and 3. FIG. 2 shows a sectional view of essential parts of a scroll compressor according to the present invention, and the same reference numerals as in FIG. 1 represent the same or equivalent parts. This scroll compressor has a fixed scroll 2 equipped with a valve device 8 that can release gas in a compression space 6 near the center (high pressure side) into a compression space 7 near the outer periphery (lower elevation). As shown in detail in FIG. 3, this valve device 8 includes an end plate 2a of the fixed scroll 2.
a hole 9 which is drilled in the casing 4 so that the force opens between the upper parts 9 of the casing 4 and the other force opens into the compression space 6 and the compression space 7 with the wrap 2b of the fixed scroll 2 as a boundary;
The valve body 10 includes a valve body 10 having pressure receiving portions at both ends and slidably inserted into the hole 9, and a retaining ring 11 attached to the inner wall of the hole 9 to prevent the valve body from being removed. A stepped portion 10a is formed on the lower receiving surface of the valve body 10, and the lower inner wall r of the hole 9 serves as a stopper for regulating the amount of downward movement of the valve body 10 and a seat of the valve body 10. A stepped portion 9a is formed which also serves as a step. When the pressure in the compression space 6 is lower than the pressure in the upper space 4a (discharge lower side), the valve body 10 moves into the upper space 4.
The lower pressure-receiving portion of the valve body 10 contacts the wrap 2b and is compressed 9 times 6
and the compression space 7, and when the pressure in the compression space 6 becomes higher than the pressure in the upper space 4a, the valve body 10 is pushed up by the pressure difference, and the compression space 6 and the compression space 7 are communicated with each other. It has become.

Next, the operation of the present invention will be explained. At startup,
When the pressure in the compression space 6 becomes higher than the pressure in the upper space 4a, the pressure difference causes the valve body 10 of the valve device 8 to be pushed up as shown in FIG. 3. As a result, the compression space 6 on the high pressure side
Since the mocha on the high pressure side escapes to the low pressure side by communicating with the compression space 7 on the low pressure side, the load at the time of startup is reduced. Therefore, F
The E-compressor starts up smoothly.

Similarly, in this embodiment, an example is shown in which only one valve device 8 is provided, but a plurality of valve devices 8 may be provided.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to prevent the pressure in the compression space from rising excessively at the time of startup, so that the startup load can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional scroll compressor, Fig. 2 is a sectional view showing a scroll compressor of the present invention, and Fig. 3 is a detailed sectional view of the valve device in Fig. 2.◇ 1... Orbiting scroll 1a... end plate 1b...
Wrap 2...Identification scroll 2a...End plate 2
b...Wrap 4a...Upper space 6...Sensor wire space near the center 7...Kingen condensed space near the outer periphery 8...Valve device 9...Hole 10...Valve body . Rod tmc

Claims (1)

[Scope of Claims] An orbiting scroll and a fixed scroll each consisting of a 1° end plate and a thinly wound wrap standing upright on the end plate, both scrolls are combined with each other with the wraps facing inward, and each In a scroll fluid machine in which an orbiting scroll is rotated relative to a fixed scroll so that the volume of the space formed by the wrap and the end plate decreases as it moves toward the center of the scroll, the fixed scroll has a compression space near the center. A valve device is provided that allows the fluid inside to escape into the compression space near the outer periphery, and the valve device is configured to open due to the differential pressure when the pressure in the compression space near the center becomes higher than the discharge pressure. A scroll fluid machine featuring: 2. In claim 1, the valve device is bored in the fixed scroll end plate, one side opens to a high pressure chamber where the discharge pressure is generated, and the other side opens to the high pressure chamber where the discharge pressure is generated, and the other side has a compression chamber near the center with the wrap of the fixed scroll as a boundary. A hole opening into the space and a compression space near the outer periphery, and a valve body having pressure receiving surfaces at both ends and slidably inserted into the hole, and when the pressure in the compression space near the center is lower than the discharge pressure. When the valve body is pressed against the lap side and blocks the compression space near the center and the compression space near the outer periphery, and the pressure in the compression space near the center becomes higher than the discharge pressure, the valve body moves due to the pressure difference and moves toward the center. A scroll fluid machine characterized by having a configuration in which a compression space and a compression space near the outer periphery are communicated with each other.