JPH1137305A - Labyrinth seal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve sealing action by providing groove-shaped recess parts extending in the radial direction in a zone of grooves or raised parts and mak ing end faces of these recess parts open to a chamber. SOLUTION: A rotating cylinder 1 is surrounded by a casing 2, and a bottom of this casing 2 is formed by a flange 3. A labyrinth seal 4 is arranged between this flange 3 and end face of the rotating cylinder 1 facing the flange 3. In this labyrinth seal 4, a large number of grooves 6 and raised parts 7 are concentrically arranged, and in a zone of these grooves 6 and the raised parts 7, a large number of groove-shaped recess parts 8 are provided extending in the radial direction located with the same angular interval to each other. The end face of these recess parts 8 is made open to chambers 5 and 10. By this, sealing performance can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a labyrinth seal between the end face of a rotating body and a stationary flange, which advantageously forms a restriction of a chamber for containing a gaseous medium, said labyrinth seal comprising: A plurality of grooves provided on the body side and extending concentrically with the rotating body are provided, and in these grooves, ridges provided on the flange side having a cross section matching these grooves are provided in the grooves. It is of a type that engages in a contactless manner with the smallest possible spacing.

[0002]

2. Description of the Related Art Various types of labyrinth seals are known. What all these known labyrinth seals have in common is that they form a virtually contactless seal between two parts that are movable relative to each other.

[0003] Such labyrinth seals are in particular used in general for sealing chambers containing gaseous media of different pressures.

[0004] However, known labyrinth seals are:
The disadvantage is that a complete seal cannot be guaranteed. That is, the presence of a small gap has the disadvantage that the corresponding medium, even in small quantities, reaches from one chamber to the other.

[0005] Such leakage losses result in undesirable pressure changes that reduce efficiency.

Heretofore, the labyrinth seals in the radial direction have been incompletely or only marginally achieved, especially at the end faces of the rotating cylinders, due to the absence of relative speed.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a labyrinth seal of the type described at the outset in such a way that an improved sealing effect can be obtained with simple structural measures.

[0008]

According to the present invention which solves this problem, a groove-like concave portion extending in the radial direction is provided in the region of the groove or the raised portion, and the end face side of these concave portions is a chamber. It is open toward.

[0009]

According to the rotation speed of the rotating body, for example, the rotating cylinder, the molecules of the leaked gas which have been collected in the groove-shaped recess through the labyrinth seal in the prior art are directed radially outward toward the chamber. Sent.

This has resulted in a significantly improved seal. This seal is comparable in efficiency to common seals whose efficiency is affected by friction losses.

The use of a labyrinth seal constructed in this way enables a frictionless movement of the rotating body which permits a very high rotational speed. Also, a long service life is guaranteed and the maintenance costs are low.

Very high operating reliability is obtained because it is not necessary to lubricate the parts which are movable relative to one another.

According to a preferred embodiment of the invention, a groove or groove-shaped recess is formed in the ring, which can be connected as a separate part to the rotating body. This allows very inexpensive manufacturing. This is the case even if the flange-like groove is provided in a ring that can be fixed to the flange.

According to another aspect of the invention, the groove-shaped recess extends to the area of the furthest or last groove away from the chamber or slightly beyond this last groove, so that the bulges All molecules supplied through the gap formed between the groove and the groove are collected in the recess and guided back in the direction of the chamber.

According to another embodiment of the invention, the groove-shaped recess extends over the entire width of the labyrinth seal, preferably slightly beyond the width of the labyrinth seal, formed by the groove and the ridge. ing.

[0016] Further advantageous embodiments of the invention are described in the dependent claims.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows a rotary seal device. The basic structure of the rotary seal device is a rotary cylinder 1
And a casing 2 surrounding the rotary cylinder 1. The casing 2 has a flange 3 forming the bottom of the casing 2.

The rotary cylinder 1 can be driven via a motor 9.

A labyrinth seal 4 is provided between the flange 3 and the end face of the rotary cylinder 1 facing the flange 3.
The labyrinth seal 4 is provided in the connection area between the flange 3 and the rotary cylinder 1 in the chambers 5 and 6.
A seal between the and the intermediate chamber 11. In this case, the chambers 5 and 10 (in which high-pressure gaseous medium is present) are limited by the rotating cylinder 1 and the wall of the casing 2, while the intermediate chamber 11 is It is formed by a part of the end face side of the cylinder 1 and the flange 3. The medium present in the intermediate chamber 11 is less than the medium present in the chambers 5,10.

As shown in particular in FIGS. 2 to 5, the labyrinth seal 4 consists of a number of concentrically arranged grooves 6 and ridges 7. These grooves 6
And the ridges 7 are arranged alternately in the rotary cylinder 1 and in the flange 3, the cross sections of which are designed to engage one another with the smallest possible gap.

Furthermore, the rotary cylinder 1 has a groove /
In the area of the ridges 6, 7, there are a number of radially extending groove-shaped recesses, which are located at the same angular spacing from one another, these recesses being open towards the outside of the rotary cylinder 1. And extends slightly beyond the width of the labyrinth seal 4.

The depth of the groove-shaped recess 8 is larger than the depth of the groove 6.

Most of the gas molecules entering the groove-shaped recess 8 along the labyrinth seal 4 are sent radially outward by centrifugal force generated by the rotation of the rotary cylinder 1.

As a result, a sealing property which has not been obtained in the conventional non-contact seal is obtained.

[Brief description of the drawings]

FIG. 1 is a partial longitudinal sectional view of an apparatus provided with a labyrinth seal according to one embodiment of the present invention.

FIG. 2 is a diagram showing details of a portion indicated by reference numeral II in FIG. 1;

FIG. 3 is a view showing details of a portion indicated by an arrow III-III in FIG. 2;

FIG. 4 is a lower side view showing details of a portion viewed in a direction of an arrow IV in FIG. 1;

FIG. 5 is a plan view showing details of a portion viewed in the direction of arrow V in FIG. 1;

[Explanation of symbols]

1 rotating cylinder, 2 casing, 3 flange, 4 labyrinth seal, 5 chambers, 6 grooves,
7 ridge, 8 recess, 9 motor, 10 chambers,
11 Intermediate room

Claims (5)

[Claims] 1. A labyrinth seal between the end face of the rotating body (1) and a stationary flange (3), which preferably forms a restriction of a chamber (5, 10) for containing a gaseous medium. A plurality of grooves (6) provided on the rotating body side and extending concentrically with the rotating body, and a cross section corresponding to these grooves (6) is formed in these grooves (6). Having a flange (7) provided on the flange side in a contactless manner with the groove (6) as small as possible, wherein the groove (6) or the ridge is provided. In the region (7), groove-shaped recesses (8) extending in the radial direction are provided, and the end faces of these recesses (8) are open toward the chambers (5, 10). The labyrinth seal. 2. The labyrinth seal according to claim 1, wherein the groove-shaped recess (8) is provided in the region of the groove (6) and the ridge (7) of the rotating body (1). 3. A labyrinth seal (4) in which a groove-like recess (8) is formed by a groove (6) and a ridge (7).
A labyrinth seal according to claim 1 or 2, extending over the entire width of the labyrinth. 4. The labyrinth seal according to claim 1, wherein the groove-shaped recesses are arranged at the same angular interval. 5. The labyrinth seal according to claim 1, wherein the labyrinth seal (4) is provided in a ring connectable to the rotating body (1) and / or the flange (3).