JPH04123386U - scroll compressor - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent damage to the spiral wraps 12 and 16 that limit the discharge chamber 22 at the center of the spiral when the discharge gas pressure increases and the suction gas pressure decreases. [Configuration] The discharge chamber 22 and the compression chamber 19a1 adjacent to the outside thereof,
A pair of pressure equalizing passages 41a and 41b are provided which communicate with the pressure in the discharge chamber 22 and the compression chamber 19.
Check valves 42a and 42b are interposed which open only when the differential pressure between the pressures in a1 and 19b1 exceeds a predetermined value.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a scroll compressor that is incorporated into a vehicle air conditioner or the like.

0002

[Conventional technology]

An example of a conventional scroll compressor is shown in FIG. In Fig. 3, reference numeral 1 denotes a closed housing, which includes a cup-shaped body 2 and a bolt 3 attached thereto. The front end plate 4 is fastened to this with bolts 5. It consists of a cylindrical member 6. The main shaft 7 passing through this cylindrical member 6 has bearings 8 and 9. It is rotatably supported by the housing 1 via. A fixed scroll 10 and an orbiting scroll 14 are arranged in the sealed housing 1. There is. This fixed scroll 10 has an end plate 11 and a spiral wrap 12 erected on its inner surface. The end plate 11 is fastened to the cup-shaped main body 2 by bolts 13. End plate 11 By bringing the outer peripheral surface of the cup-shaped body 2 into close contact with the inner peripheral surface of the cup-shaped main body 2, A discharge cavity 31 is formed on the outside of the end plate 11, and a discharge cavity 31 is formed on the inside of the end plate 11. The suction chamber 28 is limited. In addition, a discharge passage 29 is bored in the center of the end plate 11. The discharge passage 29 is fastened to the outer surface of the end plate 11 together with a retainer 35 by a bolt 36. It is opened and closed by a discharge valve 30.

0003 The orbiting scroll 14 includes an end plate 15 and a spiral wrap 16 erected on the inner surface of the end plate 15. , this spiral wrap 16 is substantially identical to the spiral wrap 12 of the fixed scroll 10. It has the shape of The orbiting scroll 14 and the fixed scroll 10 are eccentric from each other by the orbital radius, and The two are interlocked as shown with an angular shift of 180°. Thus, The chip seal 17 embedded in the tip surface of the spiral wrap 12 is in close contact with the inner surface of the end plate 15. The chip seal 18 embedded in the tip surface of the spiral wrap 16 is in close contact with the inner surface of the end plate 11. , the sides of the spiral wraps 12 and 16 are in line contact at multiple points, and are almost in contact with the center of the spiral. A plurality of compression chambers 19a and 19b are formed with dot symmetry. A drive bush 21 is installed inside a cylindrical boss 20 protruding from the center of the outer surface of the end plate 15. is rotatably fitted through a bearing 23, and a hole drilled in this drive bush 21. An eccentric pin 25, which is eccentrically protruded from the inner end of the main shaft 7, is rotatably inserted into the inner end of the main shaft 7. There is. A balance weight 27 is attached to this drive bush 21. ing. In addition, 26 is a rotation prevention mechanism that also serves as a thrust bearing, and 37 is a rosette fixed to the main shaft 7. It's thwaite.

0004 When the main shaft 7 is rotated, the eccentric pin 25, drive bush 21, boss 20 The orbiting scroll 14 is driven through an orbiting drive mechanism consisting of, etc. 14 is a circle whose radius is the revolution radius while being prevented from rotating by the rotation prevention mechanism 26 It revolves around the orbit. Then, the line contact area between the spiral wraps 12 and 16 gradually As a result, the compression chambers 19a, 19b reduce their volume. While moving towards the center of the spiral. Along with this, the gas flowing into the suction chamber 28 through the suction port (not shown) becomes spiral-shaped. It is taken into each compression chamber 19a, 19b from the outer terminal opening of the wraps 12 and 16 and is compressed. while reaching the central discharge chamber 22, from here it passes through the discharge passage 29 and pushes open the discharge valve 30. It is discharged into the discharge cavity 31 and flows out from there through a discharge port (not shown).

[0005]

[Problem that the idea aims to solve]

Damage to the evaporator fan or clogged condenser of the vehicle air conditioner, When problems such as dirt or damage to the condenser fan occur, the discharge gas pressure of the compressor The force increases abnormally and the suction gas pressure decreases. Then, the scroll compressor The pressure inside the discharge chamber 22 in the center of the crawl space and the spiral wraps 12 and 16 in this discharge chamber 22 are separated. The pressure difference between the pressure inside the pair of compression chambers 19a1 and 19b1 adjacent to the outside is abnormally large. As a result, the inner end portions of the spiral wraps 12 and 16 may be damaged.

[0006]

[Means to solve the problem] This invention was proposed to solve the above problems, and its gist is as follows: However, each fixed scroll is made up of a spiral wrap on the inner surface of the end plate. By interlocking the orbiting scroll and the orbiting scroll, a point pair is created with respect to the center of the spiral. The system forms multiple compression chambers and revolves the orbiting scroll while preventing its rotation. After compressing the gas sucked into the compression chamber by making a swirling motion, a spiral In a scroll compressor that discharges from a central discharge chamber, the discharge chamber and A pair of equal pressure chambers that communicate with a pair of compression chambers adjacent to each other on the outside of the spiral wrap. A passage is provided, and the pressure in the discharge chamber is equalized by the pair of pressure equalizing passages. Each valve is equipped with a check valve that opens only when the pressure rises above a predetermined value. A scroll compressor is characterized by:

[0007]

[Effect]

Since this invention has the above configuration, the pressure inside the discharge chamber is reduced by a pair of compressors. When the pressure in the chamber rises by more than the set value, the check valve opens and the high pressure gas in the discharge chamber is released. flows into a pair of compression chambers through a pair of pressure equalization passages and check valves installed in these passages. Then, the pressure in the discharge chamber and the pair of compression chambers is equalized.

[0008]

【Example】

One embodiment of the invention is shown in FIGS. 1 and 2. A pair of spiral wraps 12 and 16 are provided in the discharge chamber 22 and adjacent to each other on the outside thereof. A pair of pressure equalizing passages 41a and 41b that communicate the compression chambers 19a1 and 19b1 with the discharge passage 29 are connected to a fixed stage. A check valve 42 is provided in the end plate 11 of the crawler 10, and a check valve 42 is provided in the middle of each pressure equalizing passage 41a, 41b. a and 42b are interposed. The check valves 42a and 42b are energized by the valve bodies 43a and 43b. It consists of coil springs 44a and 44b.

[0009] However, due to an abnormality in the air conditioner or the like, the pressure in the discharge chamber 22 may be reduced to one of the compression chambers 19a1, When the pressure in 19b1 increases by more than a predetermined value, the valve bodies 43a and 43b of each check valve 42a and 42b each check valve 42 by moving against the elastic force of the coil springs 44a and 44b. a and 42b are open. In this way, the gas in the discharge chamber 22 flows through the discharge passage 29, the pressure equalization passages 41a, 41b, and the check valve 42a. , 42b into the compression chambers 19a1 and 19b1, and the pressure of the discharge chamber 22 and the compression chambers 19a1 and 19b1 is equalized. be done.

0010

[Effect of the idea]

In this invention, the pressure in the discharge chamber increases by more than a set value than the pressure in the pair of compression chambers. When this occurs, the check valve opens and the high pressure gas in the discharge chamber passes through each pressure equalization passage and check valve. The air flows into the pair of compression chambers, and the pressure in the discharge chamber and the pair of compression chambers is equalized. As a result, the discharge gas pressure of the scroll compressor increases abnormally, and the suction gas pressure Even if the Prevents damage by preventing excessive load from being applied to the spiral wrap can.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of one embodiment of the present invention.

FIG. 2 is a sectional view taken along arrow F of the above embodiment.

FIG. 3 is a longitudinal sectional view showing a conventional scroll compressor.

[Explanation of symbols]

10 Fixed scroll 14 Orbital scroll 19a1 compression chamber 19b1 compression chamber 22 Discharge chamber 41a Equal pressure passage 41b Pressure equalization passage 42a Check valve 42b Check valve

Claims (1)

[Scope of utility model registration request] Claim 1: A plurality of compression chambers are formed point-symmetrically with respect to the center of the spiral by interlocking a fixed scroll and an orbiting scroll each having a spiral wrap erected on the inner surface of an end plate. , a scroll type compressor that compresses the gas sucked into the compression chamber by causing the orbiting scroll to revolve while preventing its rotation, and then discharges the gas from the discharge chamber in the center of the spiral; A pair of pressure equalizing passages are provided in communication with a pair of compression chambers adjacent to each other on the outside of the spiral wrap, and the pressure inside the discharge chamber is lower than the pressure inside the pair of compression chambers through these pair of pressure equalization passages. A scroll type compressor characterized in that each scroll type compressor is equipped with a check valve that opens only when the temperature rises above a predetermined value.