JPH05157063A - Scroll type fluid machine - Google Patents

Abstract

PURPOSE:To form a thin guide pressure hole for generating effect of suppressing pressure variation, and to charge a stable back pressure load on a fixed scroll by providing a hole on the end plate of a fixed or a rotating scroll, and by inserting a tube into the hole to form a moving pressure hole. CONSTITUTION:When a rotating scroll 2 is revolved by a motor, the gas absorbed into a closed space 24 between the scroll 2 and a fixed scroll 1 reaches the center part while being compressed, and is discharged outside from a discharge port 13 through a high pressure chamber 42. A back pressure load based on the gas pressure in a high pressure chamber 42 as well as in an intermediate pressure chamber 40, works on the fixed scroll 1, which is pressed to the rotating scroll 2, and gas leakage is prevented thereby. A hole 41a is formed on an end plate 11 of the fixed scroll 1, and a thin tube 41b of fixed inner diameter like a capillary tube is inserted into the hole 41a, to form a guide pressure hole 41 for communicating the closed space 24 to the intermediate pressure chamber 40, and a stable back pressure load is thus charged on the fixed scroll.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type fluid machine used as a compressor or an expander.

[0002]

2. Description of the Related Art FIG. 2 is a vertical sectional view of a conventional scroll type compressor. The interior of the closed housing 8 is partitioned by a discharge cover 31 into a high pressure side 44 and a low pressure side 45. Inside the low-pressure side 45, a scroll type compression mechanism C is arranged at an upper part thereof and an electric motor M is arranged at a lower part thereof, which are interlockingly connected to each other via a rotary shaft 5. The electric motor M includes a rotor Ma and a stator Mb, the rotor Ma is fixed to the rotating shaft 5, and the stator Mb is fixed by being press-fitted into the hermetically sealed housing 8.

The scroll compression mechanism C comprises a fixed scroll 1 and an orbiting scroll 2. The fixed scroll 1 includes an end plate 11 and a spiral wrap 12 provided upright on the inner surface of the end plate 11. The discharge port 1 is provided at the center of the end plate 11.
3 is provided. The orbiting scroll 2 is provided with an end plate 21 and a spiral wrap 22 provided upright on the inner surface of the orbiting scroll 2, and a drive bush 54 is rotated through a orbiting bearing 73 in a boss 23 provided upright on the outer surface of the end plate 21. The eccentric pin 5 which is freely inserted and protrudes from the upper end of the rotary shaft 5 into a slide hole 55 formed in the drive bush 54.
3 is slidably fitted.

The fixed scroll 1 and the orbiting scroll 2 are eccentric with respect to each other by a predetermined distance, and are meshed with each other at an angle of 180 degrees to form a plurality of closed spaces 24. The orbiting scroll 2 is a closed housing 8
A slidably supported on a frame 6 fixed inside and allowing rotation of the swivel scroll 2 between the swivel scroll 2 and the frame 6 but preventing the rotation thereof. The mechanism 3 is provided.

The fixed scroll 1 is floatably mounted on a frame 6 via a support spring 32 arranged on the outer periphery of the end plate 11.
Supported by. On the back surface of the end plate 11 of the fixed scroll 1, a concentric cylindrical flange 15 centered on the center thereof,
16 is protruded upward, and is enclosed by the cylindrical flanges 38 and 39 protruded downward on the lower surface of the discharge cover 31 between these in a sealed and slidable manner. An intermediate pressure chamber 40 is formed, and the intermediate pressure chamber 40 communicates with the sealed space 24, which is in the middle of compressing gas, through a pressure guiding hole 41 formed in the end plate 11. A high pressure chamber 42 is formed on the inner peripheral side of the intermediate pressure chamber 40, and a low pressure chamber 43 is formed on the outer peripheral side. The upper end of the rotary shaft 5 is supported by an upper bearing 71 provided on the frame 6, and the lower end thereof is supported by a lower bearing 72.

By driving the electric motor M, the orbiting scroll 2 is driven by a revolving orbiting mechanism composed of a rotating shaft 5, an eccentric pin 53, a drive bush 54, a boss 23, etc., and the orbiting scroll 2 is rotated by a rotation preventing mechanism 3. While being blocked, it makes a revolution revolution motion on a circular orbit having a radius of revolution revolution. Then, the gas is sucked into the suction pipe 8
After passing through 2, it enters the low-pressure side 45, passes through the passage 61, and is sucked into the closed space 24 from the low-pressure chamber 43. Then, as the volume of the closed space 24 decreases due to the orbiting motion of the orbiting scroll 2, the airtight space 24 is compressed and reaches the central portion, and enters the high pressure side 44 from the discharge port 13 through the high pressure chamber 42, and from there, the discharge pipe 83. Is discharged to the outside.

At this time, a back pressure load based on the gas pressure in the high pressure chamber 42 and the intermediate pressure chamber 40 acts on the fixed scroll 1, and the fixed scroll 1 is pressed against the orbiting scroll 2 so that the gas is discharged from the closed space 24. Will be prevented from leaking. When the liquid is sucked into the closed space 24, the fixed scroll 1 floats and escapes the liquid, thereby preventing the scroll type compression mechanism C from being damaged. Although the drawing shows the intermediate pressure chamber 40 formed on the back side of the fixed scroll 1, there is also one in which the intermediate pressure chamber 40 is provided on the back side of the orbiting scroll 2. The hole 41 is formed in the end plate 21 of the orbiting scroll 2.

[0008]

In the conventional scroll type fluid machine described above, the closed space 2 is formed through the pressure guiding hole 41.
4 and the intermediate pressure chamber 40 communicate with each other.
1 is a long dimension, and the smaller the inner diameter, the more desirable. This is because the pressure change occurs in the closed space 24 at a constant cycle, but if the pressure guiding hole 41 is long and thin, the propagation of this pressure change is delayed and the pressure fluctuation in the intermediate pressure chamber 40 is reduced. As a result, a stable back pressure load can be applied to the fixed scroll 1.

The pressure fluctuation of the intermediate pressure chamber 40 can be reduced by increasing the volume of this chamber, but when the displacement of the compression mechanism C is small, the volume of the intermediate pressure chamber 40 becomes a so-called dead volume. , The compression efficiency decreases, and in order to avoid this, the volume of the intermediate pressure chamber 40 must be reduced, and therefore, it becomes necessary to make the pressure guiding hole 41 elongated. .. However, the pressure guide hole 41 having a small inner diameter, for example, a diameter of 1 mm or less is formed in the end plate 1.
It is difficult to perform the perforation processing on No. 1, and this has been an obstacle to improving the compression performance.

In view of the above circumstances, the present invention provides means for enabling the provision of pressure guiding holes having a small inner diameter.

[0011]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a fixed scroll and a orbiting scroll formed by vertically arranging spiral wraps on the inner surface of each end plate are meshed with each other. A closed space is formed, and the fixed scroll or the orbiting scroll is directed toward the orbiting scroll or the fixed scroll by the fluid pressure introduced from the closed space through the pressure guiding hole into the intermediate pressure chamber formed on the back side thereof. In the scroll type fluid machine configured to be pressed by pressing, the pressure guide hole is formed by forming a hole in the end plate of the fixed scroll or the orbiting scroll and inserting a pipe having a predetermined inner diameter into the hole. The present invention relates to a scroll type fluid machine characterized by the following.

[0012]

Since the present invention has the above-mentioned structure, the end plate of the fixed scroll or the orbiting scroll is provided with a hole having a larger diameter, and a pipe having a predetermined inner diameter is inserted into this hole to reduce the inner diameter. A pressure guide hole is freely provided. As a result, the pressure fluctuation in the intermediate pressure chamber that communicates with the closed space via the pressure guiding hole is reduced, and a stable back pressure load can be applied to the fixed scroll or the orbiting scroll.

[0013]

FIG. 1 is a partial vertical sectional view showing an essential part of a scroll type compressor according to an embodiment of the present invention. The pressure guiding hole 41 that connects the closed space 24 and the intermediate pressure chamber 40 is provided as follows. That is, the end plate 11 of the fixed scroll 1
A hole 41a having a large diameter is formed in the hole 41a, and a tube 41b having a predetermined inner diameter, for example, a tube having a small inner diameter such as a capillary tube is inserted into the hole 41a. Other configurations are similar to those of the conventional one shown in FIG. 2, and corresponding members are designated by the same reference numerals. Therefore, even if it is difficult to directly drill the pressure guiding hole 41 having the predetermined inner diameter in the end plate 11, the pressure guiding hole 41 having the small inner diameter can be freely provided. For this reason, the inside of the intermediate pressure chamber 40 has a pressure guiding hole 4 with a small inner diameter.
1 is communicated with the closed space 24 through 1 to be placed in a stable pressure state with little fluctuation.
It is possible to apply a stable back pressure load.

In this embodiment, a pressure guide hole for connecting the closed space and the intermediate pressure chamber is inserted, and a pipe having a predetermined inner diameter is inserted into the hole formed in the end plate of the fixed scroll or the orbiting scroll. Since the pressure guiding hole having a small inner diameter can be freely obtained, as a result, a stable back pressure load can be applied to the fixed scroll or the orbiting scroll, and a compressor with improved performance can be provided.

[0015]

In the scroll type fluid machine of the present invention, a pressure guide hole is formed by forming a hole in the end plate of the fixed scroll or the orbiting scroll and inserting a pipe having a predetermined inner diameter into this hole. Therefore, a long and narrow pressure guiding hole can be provided, and a stable back pressure load can be applied to the fixed scroll.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view of an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a conventional scroll compressor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed scroll 2 Orbiting scroll 11 End plate 12 Wrap 21 End plate 22 Wrap 24 Sealed space 40 Intermediate pressure chamber 41 Pressure guide hole 41a Hole 41b Pipe having a predetermined inner diameter

Claims (1)

[Claims] 1. A fixed scroll formed by vertically arranging a spiral wrap on the inner surface of each end plate and an orbiting scroll are meshed with each other to form a closed space, and the fixed scroll or the orbiting scroll is provided on the back side thereof. In the scroll type fluid machine, which is pressed toward the orbiting scroll or the fixed scroll by the fluid pressure introduced from the closed space through the pressure guiding hole formed in the intermediate pressure chamber, A scroll-type fluid machine characterized in that the pressure guide hole is formed by forming a hole in an end plate of the scroll and inserting a tube having a predetermined inner diameter into the hole.