JPS5851292A - Rotary fluid machine - Google Patents

Abstract

PURPOSE:To increase the volumetric efficiency of a compressor, by forming a groove in the sliding surface of each side plate near the cylinder top where it is held in contact with a rotor, providing a seal member shaped such that it is fitted in the groove with proper clearance, and thereby reducing leakage of gas. CONSTITUTION:A rectangular groove 9 having a small depth, as shown by the broken line in the drawing, is formed in the sliding surface of each side plate 11 where it is held in sliding contact with a rotor 2, and a sheet-like seal member 10 having a thickness slightly smaller than the depth of the groove 9 and having substantially the same shape as that of the groove 9 is fitted into the groove 9, so that a floating seal is constituted by the seal member 10 and the groove 9. In the above arrangement, the seal member 10 is held in contact with the groove 9 by a force F1 caused by pressure difference while it is urged onto the rotor 2 by a force F2 caused also by pressure difference. Thus, it is enabled to reduce the amount of gas leaked through the clearance between the rotor and the side plates.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary fluid machine, and particularly to prevention of fluid leakage in a rotanide clearance of a sliding vane rotary compressor.

As shown in Fig. 1, a conventional sliding vane compressor includes a cylinder 1 having a cylindrical space inside, a rotor 2 eccentrically installed in the cylinder 1 to rotate, and a rotor 2 installed in the cylinder 1 to rotate. Side plates (not shown) that are fixed to both sides, seal the blade chamber 3, which is the internal space of the cylinder 1, on the sides and support the rotor 2 with a bearing such as a needle bearing, and a slit 4 provided in the rotor 2. It consists of a member 76 that is slidably engaged. 6 is a suction hole formed in the cylinder 1, 7 is a discharge hole formed in the cylinder 1, and the cylinder top 8 is the part that separates the blade chamber 3 of the cylinder 1 into the discharge side and the suction side. In a rotary compressor, gas leaks from the discharge side to the suction side (in the six directions of arrows in Figure 1) at the rotanide clearance near the top, which is the boundary between the discharge side and suction side where the largest pressure difference occurs. generated and low volumetric efficiency r
was invited.

By reducing the rotanide clearance, gas leakage pipes in the rotanide can be reduced, but there is a limit to the rigidity of bearings such as two-dollar bearings that support the rotor 2 on the side plates, and liquid compression Alternatively, high pressure is applied to the rotor due to overcompression of gas, etc., which causes the rotor 2 to tilt slightly, causing contact between the side plate and the rotor 2, causing increased torque and seizure. Therefore, there is a limit to reducing the rotanide clearance.

The present invention is intended to improve the above-mentioned problems, and one embodiment thereof is shown in FIGS. 2 to 4. For example, a rectangular shallow groove 9 is formed in the sliding surface of the both side plates on the sliding surface with the rotor 2 at a position near the rectangular broken line shown in FIG. A floating seal is formed by fitting and inserting a sheet-like seal member 10 having substantially the same shape and a shape that can be easily fitted into the groove 9.

FIG. 3a is an enlarged view of the BB cross section in FIG. 2. Rotor 2. The gap between the sea 1 sealing member 101 and the side plate 11 is defined as the gap 12. Gap 13° Gap 14 and Gap 16
Considering the four locations, since the gap 12 is located on the discharge side, the pressure is higher in the gap 12 than in the gap 13 located on the suction side. Therefore, a force F1 due to the pressure difference acts on the sealing member, and the sealing member 1o comes into contact with the groove 9 at the suction side end 16 of the groove 9. Therefore, the gap 14
The pressure in the gap 12 is almost equal to the pressure in the gap 15.
The pressure in the gap 12 is between the pressure in the gap 12 and the pressure in the gap 13. Therefore, a force F2 due to the pressure difference acts on the seal member 10, and the seal member 10 is pressed against the rotor 2.

In this way, the amount of gas leaking through gap 15 is reduced and gaps 12 and 13 can maintain a high pressure difference.

Further, even if the vane 6 protrudes slightly from the rotor 2 due to a difference in coefficient of thermal expansion, the high-pressure side end 17 of the seal member 10 is designed so that the vane 5 and the seal member 10 can slide smoothly. For example, the thickness is changed in an arc shape.

Note that arrow C in FIGS. 3a and 4 indicates the direction of movement of the rotor side surface.

Figure 3 shows the pressure distribution in the gap 15, Figure 3C shows the pressure distribution in the gap 1.
This is an explanation showing the pressure distribution of No. 4. Figure 3 S and Figure 3 C
Pl indicates the pressure in the gap 13, and P2 indicates the pressure in the gap 12.

FIG. 4 shows another embodiment of the present invention, in which even if the sealing member 10 first comes into close contact with the bottom surface of the groove 9, gas flows from the gap 12 to the gap 14, causing a force F2 due to the pressure difference.
The groove 18 on the high pressure side of the bottom surface of the groove 9 is configured to be slightly deeper than the other portions. Therefore, even if the sealing member 10 is initially in close contact with the bottom surface of the groove 9, the pressure near the high-pressure side portion 18 of the lower surface of the groove 9 becomes approximately equal to that of the gap 12, and the sealing member 10 is placed on the side of the rotor 2. , and a gap 14 is created.

FIG. 6 shows yet another embodiment in which, in addition to the groove 9 of the floating seal that prevents leakage from the discharge side to the suction side, there are also grooves 9 that prevent refrigerant from leaking due to the pressure difference between the blade chambers.
That is, a floating seal is used at the groove 19 for leakage in the direction of arrow E in FIG. 6, and at the groove 20 for leakage in the arrow G direction in FIG. Groove 19.
The floating seal used in 20 can be one in the shape of a partially cut ring, or one in which rectangular shapes similar to those in 9 are arranged adjacent to each other.

As described above, according to the present invention, in the gap between the rotor and the side plate,
By reducing the amount of gas leaking from the high pressure side to the low pressure side, the volumetric efficiency of the compressor can be improved.

[Brief Description of the Drawings] Fig. 1 is a front sectional view of a conventional rotary compressor, Fig. 2 is a front sectional view of a rotary compressor according to an embodiment of the present invention, and Fig. 3(a) is a front sectional view of a rotary compressor according to an embodiment of the present invention. An enlarged view of the B-B cross section, FIG. 3(b) and FIG. 3tc+ are explanatory diagrams showing the pressure distribution in the gap, FIG. FIG. 6 is a front sectional view of a rotary compressor according to yet another embodiment. 1...Cylinder, 2...Rotor, 3
...Blade chamber, 5...Vane 8...
...Cylinder top, 9...-groove, 1o...
・Seal member, 11・Φ・・・Side plate, 12, 13, 1
4.15...Gap, 17...High pressure side end of sealing member, 18...Groove on high pressure side. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 (CLl Figure 3

Claims (2)

[Claims] (1) A rotor on which a vane is slidably provided, a cylinder housing the rotor and the vane, and a blade chamber fixed to both sides of the cylinder and formed by the vane, the rotor, and the cylinder. In a rotary complete fluid machine consisting of a side plate that seals a space on its side surface, and in which the cylinder top is the point where the rotor and the cylinder are closest to each other, a groove is formed in a sliding surface between the side plate and the rotor near the cylinder top. and a sealing member having a shape that can be fitted into the groove with a gap therebetween. (2) The end portion of the sealing member located on the high pressure side is formed to have a tapered or arcuate thickness.
The rotary complete fluid machine described in Section 1. (31) The rotary complete fluid machine according to claim 1, wherein the high-pressure side of the bottom of the groove is formed deeply.