JPS5885389A - Rolling piston type compressor with two cylinders - Google Patents

Abstract

PURPOSE:To reduce the weight of an eccentric shaft by setting the eccentricity direction of a cylinder to 120-150 deg. in crank angle, and by setting the amount of eccentricity through the necessary amount of radial clearance and the maximum deflection in the eccentric shaft's division situated in the cylinder. CONSTITUTION:A rolling piston 4 to make eccentric revolutions is arranged at a cylinder 2 which forms a compression chamber 3 installed in an eccentricity of 20mum from the rotational center of the eccentric shaft 1 driven by a motor, orientated at 120-150 deg. with respect to the vane position. This eccentric shaft 1 receives a load due to the vane back pressure and the load through the rolling piston 4 because of pressure difference between high pressure chamber and low pressure chamber, where the radial clearance 10 per turn will be 20mum max. and 0mum min, as the cylinder 2 is in an eccentricity of 20mum in the direction of 120-150 deg., which is much favorable in respect of gas leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to setting the eccentric direction and the amount of eccentricity of a cylinder in a two-cylinder rolling piston compressor.

Conventionally, in this type of compressor, the cylinder was set concentrically with the rotation center of the main shaft.

In order to improve performance, when the clearance between the cylinder and rolling piston is reduced, the rolling piston and cylinder come into contact due to the deflection of the rotating shaft due to gas pressure.
There was a risk of abnormal noises and seizure of the cooling piston and eccentric part. The trap to prevent this is to either increase the rigidity of the rotating shaft or make the center of the cylinder eccentric, but in the present invention, the rigidity of the rotating shaft is not increased too much, but by making it a flexible structure and making the center of the cylinder eccentric, The objective is to provide a lightweight and efficient compressor by optimizing the clearance between the rolling piston, piston, and cylinder under actual operating conditions.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below using examples shown in the drawings.

When the rotating shaft receives gas pressure, the amount of deflection of the rotating shaft is determined by the gas pressure and the angle of the eccentric portion of the rotating shaft. FIG. 1 and FIG. 2 are diagrams schematically showing the way of deflection. The rotation angle is based on the eccentric part (A) NS on the side closer to the drive 11hHIsK. Also, the eccentric direction is based on the amount of deflection due to the gas pressure of the two eccentric parts.

12 in the direction of rotation from the vane as shown in Figures 3 and 4.
A range of 0 to 150 is suitable. In addition, the solid line shown in FIGS. 1 and 2 shows the shape of the shaft when no load is applied, and the broken line shows the shape of the shaft when the load is applied. Further, the broken lines shown in FIGS. 3 and 4 indicate the cylinder position when the cylinder is concentric with the rotation center, and the solid line indicates the cylinder position when the cylinder is eccentric from the rotation center.

' The present invention will be explained below with reference to the embodiment shown in FIG.

In the figure, (1) is an eccentric shaft driven by an electric motor, etc., and (2) is 12 points from the rotation center of this eccentric shaft and the vane position.
The compression chamber (
3), the cylinder (4) is fitted onto the eccentric shaft;
A slow rolling piston that rotates eccentrically along the inner wall of the cylinder (2), 6) is a vane that partitions the compression chamber (3) into a high pressure chamber and a low pressure chamber, and (6) is attached airtightly to one side of the cylinder (2). The side housing (7) is a partition plate (8) for partitioning the compression chambers of the two cylinders (2).
) is a hermetic shell that stores the high pressure gas discharged from the compression chamber and houses the compressor body; (91 is a spring that presses the vane (51) into the rolling piston (4);

Next, the operation of the compressor configured as described above will be explained. When the eccentric shaft (!) is rotated by the drive source, the rolling piston (4) rolls along the inner wall of the cylinder (2), and the compression chamber (3) led from the suction port (not shown) is rotated.
) is compressed and guided into the space within the shell through a discharge pulp (not shown) section. Then, it is discharged to the outside via a discharge pipe (not shown).

At this time, the eccentric shaft is loaded by the load and the back pressure of the vane through the rolling piston due to the pressure difference between the high pressure chamber and the low pressure chamber. The eccentric shaft subjected to the load causes deflection, and as a result, assuming that the cylinder and the eccentric shaft are concentric, the radial clearance between the rolling piston and the cylinder will be approximately 1 cm due to the influence of the M part and the B part on each other. Approximately 1
11! It becomes smaller at the o point and becomes larger at the 195° to 15° point. In this embodiment, the maximum deflection is about 20μ.

However, in the present invention, the cylinder is eccentric by about 20μ in the 1200 to 15o0 direction, so the radius per rotation is
In this embodiment, the leakage clearance 611 is 20 μ at maximum to 0 μ at minimum, which is good against gas leakage. However, if the eccentric shaft and cylinder are made concentric as in the past, the cylinder and rolling piston do not come into contact and the maximum is 40μ to the minimum a.
The clearance will be μ. However, 11. Generally, the amount of eccentricity of a cylinder is determined by the gas load, the load from the vane, the diameter of the eccentric shaft, the rigidity, etc. However, the eccentric direction is always constant (120° to 150° in terms of crank angle). Therefore, the present invention can be practically applied when the amount of deflection (in the cylinder) of the eccentric shaft during operation is 5 μ or more. That is, when the amount of deflection is 5 μ or less, there is no significant difference in compressor performance between eccentric assembly and concentric assembly.

This invention is constructed as described above.

It has great practical effects such as reducing the weight and size of the eccentric shaft and improving compression efficiency.

[Brief explanation of the drawing]

1 to 4 are explanatory views of the operation of the present invention. FIG. 5 is a sectional view of a two-cylinder IJ piston type compressor showing an embodiment of the present invention. (1) Fi eccentric shaft, (2) cylinder, (4) rolling piston, and (5) vane. Agent Shin Kuzuno −

Claims (1)

[Scope of Claim] A shaft having two eccentric portions that are out of phase by 1800 degrees. Two cylinders eccentric to the center of rotation of this shaft. Two rolling pistons that touch the outer periphery of the eccentric part of this shaft and move along the inner wall of each cylinder, and the outer periphery of this rolling piston. In a two-cylinder rolling piston compressor equipped with two vanes that partition the inside of the cylinder into a high-pressure chamber and a low-pressure chamber, the eccentric direction of the cylinder is 1200 degrees in crank angle.
~1500, and the amount of eccentricity is the maximum amount of deflection in the cylinder section of the eccentric shaft.