JPH0212310B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a floating intermediate ring type non-contact seal. In conventional contact seals and non-contact seals that consist of a rotating ring, an intermediate ring, and a stationary ring, the rotation speed of the intermediate ring is not necessarily 1/1 of the shaft rotation speed.
2, but was either completely stationary or approximately equal to the rotational speed of the shaft. Therefore, the sliding speed between the rotating ring or the stationary ring and the intermediate ring is high, the power loss is large, and the generation of heat on the sliding surface is also large.

The present invention is intended to eliminate these conventional drawbacks, and includes a spiral groove and an annular groove that communicates with the inner or outer ends of the intermediate ring on both sides, and communicates with each other through a communication path. When one side of the ring is slipping, fluid is drawn in by the spiral groove and placed in the annular groove to generate pressure corresponding to the pressing load. The pressure is then transmitted to the annular groove and spiral groove on the other surface through the communication path, and acts to push and spread that surface, allowing them to slide against each other. The rotational speed of the intermediate ring fluctuates until the sliding resistance of both sliding surfaces becomes the same, that is, until the sliding speed becomes the same, and stabilizes when it reaches 1/2 of the shaft rotational speed. Since the power loss on the sliding surface is proportional to the 1st to 2nd power of the sliding speed, rotating the intermediate ring at 1/2 the rotation speed of the shaft has the effect of reducing the power loss and lowering the temperature of the sliding surface. It is something.

To explain the figures, FIG. 1 is a side sectional view of the device of the present invention, and FIG. 2 is a view taken in the direction of arrow A in FIG. Insert the intermediate ring 2 in between. The stationary ring 3 is pressed against the rotating ring 1 via the intermediate ring 2 by a spring 7 inserted between the stationary ring 3 and the machine frame 8. 9 indicates the packing between the stationary ring and the machine frame, and 10 indicates the main shaft. R indicates the rotation direction of the main shaft and the intermediate ring 2. In addition, the side indicated by H in FIG. 1 is the high pressure part. The sliding surfaces between both sides of the intermediate ring, the rotating ring, and the stationary ring slide against each other to form a sealing surface, which is designed to seal in fluid.

Figure 2 is a view in the direction of arrow A in Figure 1, and shows the sliding surface 2.
1, it has a plurality of spiral grooves 6 which are not open in the outer circumferential portion 22 of the sealing surface and an annular groove 4 connecting the inner end portions of the spiral grooves 6. Also, on the opposite surface of the intermediate ring, that is, the surface 23 facing the stationary ring 3, there is a surface 2.
It has the same structure as 1 but with the spiral hand opposite. The pressure of the fluid increased in the spiral groove 6 due to the slipping of one surface is also communicated to the annular groove and spiral groove on the other surface through the communication path 5, pushing that surface open and rotating it, causing both surfaces to rotate. The speed of the intermediate ring is varied until the sliding resistance of is equal. Since both surfaces have exactly the same structure, the intermediate ring rotates at approximately 1/2 the shaft rotation speed. Since the power loss on the sliding surface is proportional to the 1st to 2nd power of the sliding speed, rotating the intermediate ring at 1/2 the rotation speed of the shaft reduces the power loss and lowers the temperature of the sliding surface. .

The present invention has such a configuration, and has a spiral groove and an annular groove on both sides of the intermediate ring of the seal component, and communicates the annular grooves on the front and back through a communication path, thereby changing the speed of the intermediate ring to the rotation of the shaft. The number is reduced to 1/2, which reduces the power loss on the sealing surface and produces the effect of lowering the temperature.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of the device of the present invention, and FIG. 2 is a view taken along arrow A in FIG. 1. Explanation of symbols: 1... Rotating ring, 2... Intermediate ring, 3... Stationary ring, 4... Annular groove, 5...
Communication path, 6...Spiral groove, 7...Spring, 8...
...Machine frame, 9...Packing, 10...Shaft, 21,
23...Side surface, 22...Outer peripheral surface.

Claims (1)

[Claims] 1 In a non-contact seal, an intermediate ring is inserted between a rotating ring and a stationary ring that are elastically pressed and sliding against each other, and both seal surfaces of the intermediate ring that correspond to the rotating ring and the stationary ring, respectively. In addition, a plurality of spiral grooves that are not open at the end of the sealing surface and an annular groove into which the fluid pressurized in the spiral grooves flows are provided, and the shapes on both sides are exactly the same, and the annular grooves on both sides are connected. A floating intermediate ring type non-contact seal featuring a communication path.