JPH03237284A - Scroll compressor - Google Patents

Abstract

PURPOSE:To make the revolution turning radius of a turning scroll small at the time of liquid compression being generated so as to prevent the damage of a compressor by providing a drive bush movably in the axial direction, and inclining a drive pin and an eccentric hole for fitting the drive pin sideways toward the tips thereof. CONSTITUTION:A drive bush 30 is fitted rotatably and movably in the axial direction through a turning bearing 73, as well as a drive pin 31 inclining sideways toward its tip is protrusively provided at the upper end face of a rotating shaft 5, in a position displaced from the shaft center by the specified quantity, and an eccentric hole 33 inclining in the same way as the drive pin 31 is bored at the drive bush 30. At the time of liquid compression, high pressure liquid from a closed space 24 flows into a chamber 35 through a hole 32. With this liquid pressure, the drive bush 30 is moved downward and inserted down to the base of the drive pin 31, so that the revolution turning radius of a turning scroll 2 become small, and liquid flows out of a mesh clearance to prevent the damage of a compressor.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a scroll compressor.

(Prior Art) FIG. 2 shows an example of a conventional scroll compressor.

As shown in FIG. 2, inside the sealed housing 8, there is a scroll type compression mechanism C in the upper part, and an electric motor M in the lower part.
is installed.

The scroll-type compression mechanism C allows the fixed scroll 11, the orbiting scroll 2, and the orbiting scroll 2 to revolve, but a rotation prevention member 3 such as an Oldham ring that prevents rotation, a fixed scroll 1, and an electric motor M are fastened to the scroll type compression mechanism C. It consists of a frame 6, an upper bearing 71 and a lower bearing 72 that pivotally support the rotating shaft 5, an orbiting bearing 73 that supports the orbiting scroll 2, a thrust bearing 74, and the like.

The fixed scroll 1 includes an end plate 11 and a spiral wrap 12 erected on its inner surface, and the end plate 11 is provided with a discharge bow 13 and a discharge valve 17 for opening and closing the same.

The orbiting scroll 2 includes an end plate 21 and a spiral wrap 22 erected on the inner surface of the end plate 21. A drive bushing 25 is mounted on the orbiting bearing 7 within a boss 23 erected on the outer surface of the end plate 21.
A drive pin 53 protruding from the upper end of the rotary shaft 5 is rotatably fitted into an eccentric hole bored in the drive bush 25 through the drive bush 25 .

A plurality of sealed spaces 24 are formed point-symmetrically by making the fixed scroll 1 and the orbiting scroll 2 eccentric to each other by the radius of revolution and meshing with each other with an angle shifted by 180°.

By driving the electric motor M, the rotating shaft 5
, drive bin 53, drive bush 25, post 23
The orbiting scroll 2 is driven through the rotation scroll 2, and the orbiting scroll 2 revolves on a circular orbit having a revolution radius while being prevented from rotating by the rotation prevention mechanism 3.

Then, the gas enters the sealed housing 8 through the suction pipe 82, cools the electric motor M, and then passes through the passage 85 formed in the frame 6 and enters the suction chamber 16 from the suction passage 15 provided in the fixed scroll l. After that, it is sucked into the closed space 24. Then, as the volume of the closed space 24 decreases due to the revolving movement of the orbiting scroll 2, it reaches the central part while being compressed, pushes open the discharge valve 17 from the discharge port 13, enters the discharge cavity 14, and further discharges. It is discharged to the outside through a pipe 83.

At the same time, lubricating oil 8 is stored in the inner bottom of the housing 8.
1 is sucked up by a pump 51 provided at the lower part of the rotary shaft 5, passes through the oil supply hole 52, and is delivered to the lower bearing 72,
After lubricating the drive bin 53, upper bearing 71, rotation prevention member 3, swing bearing 73, thrust bearing 74, etc., the chamber 61
．． The oil is discharged through the drain hole 62 and stored at the bottom of the sealed housing 8.

Note that 84 is a balance weight attached to the upper end of the rotating shaft 5.

(I! Problem to be solved by the invention) In the above conventional scroll compressor, the revolution radius of the orbiting scroll 2 is constant and cannot be changed, so when liquid is sucked into the closed space 24, There was a risk that so-called liquid compression would occur and the compressor would be damaged.

(Means for Solving the Problems) The present invention was invented in order to solve the above problems, and its gist is that a fixed scroll is formed by erecting spiral wraps on each end plate. A sealed space is formed by meshing the orbiting scroll with the orbiting scroll, and a drive pin protruding from the rotating shaft is fitted into an eccentric hole bored in a drive bush rotatably supported by the orbiting scroll, and the rotating scroll is rotated. In a scroll type compressor that compresses gas sucked into the sealed space by rotating an orbiting scroll while preventing its rotation by rotation of a shaft, the drive bushing is movable along the ring direction. In addition, the scroll compressor is characterized in that the drive bin is inclined laterally toward the tip, and the eccentric hole into which the drive bin fits is also inclined.

(Function) Since the present invention has the above configuration, when liquid compression occurs, the drive bushing moves along the axial direction, and the revolution radius of the orbiting scroll becomes smaller.

(Example) One embodiment of the invention is shown in FIG.

A drive bushing 30 is fitted within the post 23 via a swing bearing 73 so as to be rotatable and movable along the axial direction.

A chamber 35 is formed above this drive bushing 30, and this chamber 35 is connected to the closed space 20 in the central portion through a hole 32 bored in the central portion of the end plate 21 of the orbiting scroll 2.
is connected to.

A drive pin 31 is provided on the upper end surface of the rotating shaft 5 at a position eccentric from the rotation axis by a predetermined amount and is inclined laterally toward the tip. A similarly inclined eccentric hole 33 is drilled.

The rest of the structure is the same as the conventional one shown in FIG. 2, and corresponding members are given the same reference numerals.

When the rotary shaft 5 rotates, the drive bush 30 is moved by the drive pin 3 due to the centrifugal force acting on it.
Remove from 1 and move upwards. As a result, the amount of eccentricity of the drive bushing 30 increases, so the revolution radius of the orbiting scroll 2 increases. Then, the side surface of the spiral wrap 22 of the orbiting scroll 2 and the side surface of the spiral wrap 12 of the fixed scroll 1 are brought into close contact with each other with appropriate pressure. Thus, the mesh gap, i.e. the spiral wrap 22.11
The performance of the compressor is improved because the leakage of fluid from the gap between the side surfaces of the compressor is reduced and the volumetric efficiency is improved.

When liquid is sucked into the sealed space 24 and compressed, that is, when the liquid is compressed, high-pressure liquid flows from the central sealed space 24 through the hole 32 into the chamber 35, and this liquid pressure causes the drive bush 30 to be compressed. is moved downward against the centrifugal force acting on it and is inserted to the base of the drive pin 31. As a result, the amount of eccentricity of the drive bushing 30 decreases, and the revolution radius of the orbiting scroll 2 decreases. In this way, the mesh gap increases and liquid flows out from the mesh gap, thereby preventing damage to the compressor due to liquid compression.

In the above embodiment, the drive bushing 30 is moved downward by introducing the high-pressure liquid in the central closed space 24 into the chamber 35 through the hole 35, but the thrust load acting on the orbiting scroll 2 It is also possible to move the drive bush 30 downward by directly or indirectly transmitting this to the drive bush 30.

(Effects of the Invention) In the present invention, the drive bush is made movable along the axial direction, and the drive pin is inclined laterally toward the tip, and the eccentric hole into which the drive pin fits is made. Similarly, since it is tilted, the drive bushing moves along the axial direction when liquid compression occurs, and the revolution radius of the orbiting scroll becomes smaller.

As a result, damage to the compressor due to liquid compression can be prevented.

Additionally, as the rotational speed of the compressor increases, the adhesion force between the sides of the spiral wraps of the orbiting scroll and fixed scroll can be increased, preventing gas leakage from the mesoche gaps and improving the volumetric efficiency of the compressor. You can improve.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view of the main part showing one embodiment of the present invention, Fig.
The figure is a longitudinal sectional view of a conventional scroll compressor. Fixed scroll -1, end plate -11, spiral wrap ~
42, Orbiting scroll-2, End plate-21, Spiral wrap-22, Sealed space-24, Rotating shaft-5,
Drive bush - 30, drive pin - 31, eccentricity Figure 1

Claims (1)

[Claims] An airtight space is formed by meshing a fixed scroll with a spiral wrap erected on the end plate and an orbiting scroll, and an eccentric hole bored in a drive bush rotatably supported by the orbiting scroll. A scroll compressor in which a drive pin protruding from a rotating shaft is fitted to the rotating shaft, and the rotating scroll rotates around the orbit while preventing its rotation, thereby compressing the gas sucked into the sealed space. In the above, the drive bush is movable in the axial direction, and the drive pin is inclined laterally toward the tip, and the eccentric hole into which the drive pin fits is similarly inclined. Features a scroll type compressor.