JP3063479B2 - Centering support mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centering support mechanism for supporting two casings substantially concentrically at a high temperature.

[0002]

2. Description of the Related Art For example, a casing for supporting a rotor of a turbine is a member requiring heat resistance. In recent years, in order to improve heat resistance, it has been attempted to use ceramic for some of the components. When ceramic is used for some of the components, it is necessary to easily absorb the thermal expansion of the metal under high temperatures and to connect and support the casings so that their inner diameters are concentric.

A casing centering support mechanism in the case where two casings having different thermal expansions at high temperature are formed as two members will be described with reference to FIGS. FIG. 5 is a front view of the conventional centering support mechanism, and FIG. 6 is a view taken along line VI-VI in FIG.

The illustrated casing 1 comprises a first casing 2
The second casing 3 is connected and supported in a substantially concentric state, and for example, a rotor is supported inside. Radial keys 4 parallel to the center axis of the rotor (not shown) are provided at three circumferential positions on the side surface of the first casing 2. On the other hand, the U in which the radial key 4 is loosely fitted to the second casing 3 is used.
The letter-shaped grooves 5 are formed at three places, and the second casing 3 is connected to the first casing 2 by loosely fitting the grooves 5 into the radial key 4. At this time, the inner diameter 2a of the first casing 2 and the inner diameter 3a of the second casing 3 are centered. Since the radial key 4 and the groove 5 are in a loosely fitted state, even if relative deformation in the radial direction occurs between the first casing 2 and the second casing 3 due to thermal expansion in a high temperature state, the deformation is absorbed.

[0005]

The first casing 2 and the second casing 3 are relatively deformed in the axial direction (thrust direction) of the rotor at a high temperature. If the deformation in the thrust direction is the same amount of deformation at the three radial keys 4, the relative deformation is absorbed between the radial key 4 and the groove 5,
If the amount of deformation is different, biting occurs between the radial key 4 and the groove 5. If the sliding portion is bitten, the first casing 2 and the second casing 3 cannot move in the thrust direction, and there is a possibility that the heat elongation cannot be sufficiently absorbed.

[0006]

According to the present invention, there is provided a centering support for connecting a second casing substantially concentrically to a first casing for supporting a rotating body therein at a high temperature. In the mechanism, radial keys parallel to the central axis of the rotating body are provided at least at three places in the circumferential direction on the side surface of the first casing, and pieces are loosely fitted to each of the radial keys. The second casing is connected to and supported by the first casing by providing each of the pieces in the second casing and loosely fitting the piece into the groove.

[0007]

The first casing piece is fitted into the groove of the second casing to support the centering of the first casing and the second casing. When deformation occurs relatively between the first casing and the second casing, the piece slides in the groove, and the piece moves relative to the radial key, so that the deformation is absorbed.

[0008]

1 is a front view of a centering support mechanism according to an embodiment of the present invention, FIG. 2 is a view taken along the line II-II in FIG. 1, and FIG. 3 is a perspective view of FIG. is there.

As shown in FIGS. 5 and 6, the illustrated casing 11 has a first casing 12 connected and supported in a substantially concentric manner with a second casing 13 made of ceramic, and a rotor, for example, inside the casing. It is intended to be supported. Radial keys 14 that are parallel to the central axis of the rotor (not shown) are provided at three circumferential positions on the side surface of the first casing 12, and the pieces 15 are loosely fitted to the radial keys 14, respectively. On the other hand, U-shaped grooves 16 into which the pieces 15 are loosely fitted are formed in the second casing 13 at three places, and the pieces 15 and the grooves 16 are loosely fitted in surface contact. By loosely fitting the groove 16 into the piece 15, the first casing 12 and the second casing 13 are connected, and the inner diameter 12a of the first casing 12 and the inner diameter 13a of the second casing 13 are centered.

When the first casing 12 and the second casing 13 undergo relative deformation in the radial direction due to thermal expansion in a high temperature state, the pieces 15 move relatively in the groove 16 in the radial direction, and the deformation is absorbed. . Further, when relative deformation in the thrust direction occurs between the first casing 12 and the second casing 13 due to thermal expansion, the piece 15 relatively moves in the groove 16 in the axial direction, and the deformation is absorbed. At this time, when the piece 15 and the groove 16 are in surface contact, the piece 15 moves relative to the radial key 14, and the deformation is absorbed. Accordingly, the first casing 12 and the second casing 13 can be held in a concentric state by reliably absorbing the relative deformation regardless of the deformation state due to the thermal expansion.

Referring to FIG. 4, a radial key 14 and a piece 15
Another example of the supporting state will be described. FIG. 4 shows a cross section of a main part of the bridge supporting portion.

A groove 14a extending along the center of the groove 16 is formed in the radial key 14, and a groove 15a inclined with respect to the center is formed on the inner periphery of the piece 15, and the grooves 14a, 15
A leaf spring 21 is inserted over “a”. This allows
When the piece 15 is loosely fitted in the groove 16, the piece 15 is loosely fitted to the radial key 14 in a state inclined with respect to the center of the groove 16, and the piece 15 always contacts the groove 16. When relative deformation occurs between the first casing 12 and the second casing 13 due to thermal expansion, the piece 15 rotates according to the amount of deformation against the spring force of the leaf spring 21, and the piece 15 Deformation is absorbed by relative movement inside. The piece 15 is always a groove 16
, There is no impact when relative deformation occurs.

[0013]

The centering support mechanism of the present invention centers the first casing and the second casing by loosely fitting the piece into the radial key of the first casing and loosely fitting the piece into the groove of the second casing. Since the first casing and the second casing are supported, the relative deformation between the first casing and the second casing is absorbed by the sliding of the piece with respect to the groove and the movement of the piece with respect to the radial key. As a result, the relative deformation between the first casing and the second casing due to thermal expansion can be reliably absorbed and the concentric state can be maintained.

[Brief description of the drawings]

FIG. 1 is a front view of a centering support mechanism according to an embodiment of the present invention.

FIG. 2 is a view taken along line II-II in FIG.

FIG. 3 is a perspective view of FIG. 2;

FIG. 4 is a cross-sectional view of a main part of a bridge supporting portion according to another embodiment.

FIG. 5 is a front view of a conventional centering support mechanism.

FIG. 6 is a view taken along the line VI-VI in FIG. 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Casing 12 First casing 13 Second casing 14 Radial key 15 Piece 16 Groove

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Claims (1)

(57) [Claims] 1. A centering support mechanism for connecting a second casing substantially concentrically to a first casing that supports a rotating body therein at a high temperature, wherein the centering support mechanism is provided at least at three circumferential positions on a side surface of the first casing. Providing a radial key parallel to the center axis of the rotating body, loosely fitting a piece to each of the radial keys, providing grooves for loosely fitting the pieces in the second casing, and loosely fitting the pieces to the grooves. Wherein the second casing is connected to and supported by the first casing.