JPS5879700A - Shear key fixing device - Google Patents

Abstract

PURPOSE:To facilitate the assembling by fitting shear keys divided into four in circular grooves made in the innercircumferential face of a turbo casing while providing an initial positioning member when assembling the left and right chips in the circular grooves between the left and right chip lower end sections. CONSTITUTION:A shear key 3 for engaging a head cover 2 to the end section innercircumferential face of a barrel type turbo casing 1 is constructed by the up and down and left and right shear key chips 3a-3d splitted circumferentially into four. A liner 8 of same length or shorter than the shear key chip 3b is provided in a circular groove between the lower end sections of the shear key chips 3c, 3d and it is constructed such that the liner 8 will become initial positioning member at the assembling of the shear key chips 3a, 3d. Consequently the gap between each shear key chips 3a-3d can be made zero completely, thereby the shear key 3 can be assembled accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a shear key attachment device used in a barrel-shaped turbo casing such as a turbo compressor.

[Prior art]

A conventional sear key attachment device will be explained with reference to FIGS. 1 and 2. In the figure, 1 is a barrel-shaped turbo casing (hereinafter referred to as casing) used in a turbo compressor.
, 2 is a head cover attached to the inner peripheral surface of the end portion of the casing 1 with a shear key 3. The shear medium 3 is divided into a plurality of pieces in the circumferential direction and installed in a deep annular structure 4 bored in the inner peripheral surface of the end of the casing 1 as shown by the broken line in FIG. Stud 5 screwed in
The head cover 21 is disposed at the position shown by the solid line in FIG. 2, and positioned in the axial direction of the head cover 21.

The conventional device configured as described above has the following drawbacks. That is, if there is a gap between the split surfaces of the sear key after the installation of the sear key is completed, internal pressure builds up in the head cover and a large force acts on the sear key 3. When the sear key 3 is exposed to light, its rigidity decreases and the sear key 3 becomes easily deformed. Therefore, when installing a sear key, the gap t created on the split surface must be made as small as possible. However, in conventional devices, each split sear key piece is positioned independently using studs and bolts, so the gap between the split surfaces must be minimized. In order to make it smaller, it has to be processed very precisely and assembled accurately.

[Objectives and Illustration of the Invention] The present invention aims to improve the drawbacks of conventional devices, and in particular, to provide a shear key mounting device that is extremely easy to assemble when attaching the shear key, and can reduce the gap between the split surfaces. ,
An annular groove for mounting a sear key is provided on the inner peripheral surface of the end of the barrel-shaped turbo casing, and the sear key installed in this annular groove is divided into four parts in the circumferential direction to form upper, lower, left and right sear key pieces,
In the annular groove between the lower ends of the left and right shear key pieces, there is a positioning member t-aσ that determines the initial position of the left and right shear key pieces when they are assembled.

[Embodiments of the invention]

Hereinafter, one embodiment of the sear key attaching device of the present invention will be described with reference to FIGS. 3 and 4. In the figures, the same reference numerals as in FIGS. 1 and 2 indicate the same or equivalent parts.

Barrel-shaped turbo casing (hereinafter referred to as casing) 1
A head cover 2 is held on the inner surface of the end by a shear key 3. The shear key 3 is installed in an annular shape 4 bored in the inner surface of the end of the casing 1, and receives internal pressure acting on the head cover 2.

Further, as shown in Fig. 3, this sear key 3 is divided into four parts in the circumferential direction, and is composed of upper, lower, left and right sear key pieces 3 a # 3 b * 3 Cw 3 d. It's happening. Upper and lower sear key pieces 3a.

It is configured so that it can move in a 3kl radius (up and down) direction,
The upper and lower shear key pieces 3m and 3blj are installed in the groove 4 and then fixed with studs 7 that pass through the cage/gage 1.
It has become so. 8 is a liner that is the same length or slightly shorter than the 77#-piece 3b below, and this liner 8 is provided in the annular groove between the lower ends of the left and right sear key pieces 3c and 3d, and is attached to the left and right sear key pieces 3C934. It constitutes a positioning member that performs initial positioning during insertion.

Next, the procedure for attaching the sear key in the apparatus of the present invention described above will be explained. First, a liner 8 is placed at the bottom of the annular groove 4.
Install and position the left and right sear key pieces 3.
c e 3 d Incorporated into t'j-shaped groove 4.

Its initial position is determined by the liner 8. Thereafter, the upper and lower sear key pieces 3 are fixed to the annular groove 4 using the studs 7 to complete the installation. If Raina 8
The length of is slightly shorter than the lower sear key piece 3b.

<When configured, left and right sears, key pieces 30.
After assembling 3dt, upper sear key piece 3m is assembled with stud 7, and finally lower sear key piece 3bt is assembled. This makes integration even easier. In this case, when assembling the sear key piece 3bt of the knife, its both ends will hit the lower mtm of the left and right sear key pieces 3c + 3d, so
If you leave this touching part tdi, the tightening force of stud 7 will tighten the lower shear key piece 3b! Can be easily incorporated.

In addition, in the above-described embodiment, the liner 8gr positioning member is used, but instead of providing the liner 8t, the lower sear key piece 3b is used as a positioning member, and the lower sear key piece 3b is used at the beginning of the movement.
Incorporate into the btjll-shaped groove 4, and attach the 19 left and right shear key pieces 3c to the shear key piece 3b below.

3d initial positioning may be performed, and in this embodiment, the number of parts can be reduced. Also, as shown in Fig. 5, both end surfaces of the lower sear key piece 3b are
The inner diameter side is tapered 1i9 so that the width of the tapered shear key piece 3b becomes wider, and the end surfaces of the left and right shear key pieces 3c and 3d that come into contact with this taper rji9 are also tapered surfaces 10 so as to come into close contact with the tapered surface 9. If the sear key 3 is assembled last by using the lower sear key piece 3bt-stud 8 when the sear key 3 is loaded, each sear key piece 3a+3b
, 3c, and 3d can be made completely O.

In FIG. 5, parts with the same reference numerals as in FIGS. 3 and 4 indicate the same or corresponding parts, and the tapers m9 and 10 correspond to both ends of the upper sear key piece 3a. A similar effect can be expected even if the left and right shear key pieces 3c*3d are provided at one end.

〔Effect of the invention〕

As explained above, in the sear key mounting device of the present invention, the sear key is divided into four parts in the circumferential direction to form top, bottom, left and right sear key pieces. Since the positioning member t-a for initial positioning can be removed during assembly, assembly when attaching the sear key can be performed accurately and extremely easily. Further, since the gap between the split surfaces of the shear key is only between the upper shear strip and the left and right shear key pieces, there is an effect that the gap between the split surfaces can be minimized.

[Brief explanation of the drawing]

FIG. 1 is a view showing the main part of a conventional sear key mounting position, and FIG. 4 is a view showing an embodiment of the sear key mounting device of the present invention. FIG. 4 is a view along the line N-IV in FIG. 3, and FIG. 5 is a cross-sectional view showing another embodiment of the device of the present invention. l... Barrel type turbo casing, 3... Sear key, 3m... Upper sear key piece, 3b... Lower ° sear key piece, 3c... Left sear key piece, 3d... Right sear key piece, 4... annular groove, 8... liner (positioning member), 9-10... tapered surface. ￥ 1 Figure 2nd eye VJ3 mouth 4th b

Claims (1)

[Claims] 1. An annular structure in which a sear key is installed is provided on the inner circumferential surface of the end of the barrel-shaped turbo casing, and the sear key installed in this annular structure is divided into four in the circumferential direction to form upper, lower, left, and right sear keys. A sear key mounting device in which an initial positioning member is provided in an annular groove between the lower ends of the left and right sear key pieces when the left and right sear key pieces are assembled. 2. The sear key attachment device according to claim 1, wherein the positioning member is constructed of a liner having the same length as the lower sear key piece but slightly shorter. The sear key mounting arrangement according to claim 1, characterized in that the lower sear key piece is used as a positioning member. 4. At least one of the upper and lower sear key pieces has a tapered surface such that the inner diameter side of at least one of the upper and lower sear key pieces has a wider width, and the end surfaces of the left and right sear key pieces that come into contact with this tapered surface are also tapered. , the shear key attachment device according to claims 1 to 3, wherein the shear key attachment device is configured to have a tapered surface that comes into close contact with the te+/( direction).