JPH0252123B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Purpose of the Invention [Field of Industrial Application] This invention relates to the connection between a shaft and the inner ring of a rolling bearing, or the connection between a shaft and a rotating ring of a mechanical seal. This relates to a fitting used to connect a ring made of.

[Prior Art] Ceramic has greater high-temperature strength than metal materials, so it can be said that its material properties are not fully utilized until it is used in a high-temperature region. For these reasons, it has recently been considered that rolling bearings used in high temperature regions be made of ceramic.

[Problems to be Solved by the Invention] However, if the shaft is made of metal and the inner ring of the bearing attached to it is made of ceramic, there will be a difference in fuel expansion between the two, especially at high temperatures. Because it is large, it may destroy the inner ring of the bearing. For this reason, there is a desire for a technology that can reduce the influence of the difference in fuel expansion and securely fix the two, but to date, no satisfactory technology has been developed.

This also applies to other fixings between the shaft and a ring made of different materials, such as coupling the shaft to a rotating ring of a mechanical seal.

This invention was made in view of the above-mentioned circumstances, and allows rings made of different materials with different combustion expansion rates to be reliably attached to a shaft, so that even if there are temperature changes, the condition at the time of ring attachment is always maintained. It is an object of the present invention to provide a shaft-to-ring attachment that is easy to maintain and simple in construction.

(B) Structure of the Invention [Means for Solving the Problem] Corresponding to this object, the shaft and ring body mount of the present invention includes a shaft made of a first material and a second material made of a second material. A shaft mount disposed between the shaft and the annular body when fitting the annular body thereinto, the shaft mount comprising a bush and a plurality of sleeve members, the bush comprising: An annular body made of a material having substantially the same coefficient of linear expansion as the first material, and having a tapered surface forming an angle α with respect to the center line of the shaft on one side, the tapered surface being connected to the small diameter end of the annular body. The sleeve members are fitted onto the shaft via a key while facing each other so as to be located inside in the direction of the center line, and the plurality of sleeve members are made of a material having substantially the same coefficient of linear expansion as the second material. The bushing is disposed between the shaft and the ring body with the side surface in contact with the side surface of the bushing, and cooperates with the bushing so that the bushing is concentric with the shaft and both sides are aligned with the center line of the shaft. It is possible to construct an imaginary cylindrical body having a tapered surface forming an angle α, where the angle α is the diameter D at the center of the tapered surface of the bush, and the diameter D at the center of the tapered surface of the bush, and the diameter D at the center of the tapered surface of the bush. It is characterized in that tanα=D/B, where B is the distance in the center line direction.

Hereinafter, details of the present invention will be explained with reference to the drawings showing one embodiment.

In FIGS. 1 and 2, 2 is a metal shaft, and 3 is a radial ball bearing attached to the shaft 2. In FIG.

A fixture 1 is arranged between the shaft 2 and the radial ball bearing 3.

The radial ball bearing 3 consists of a bearing ring made up of an inner ring 4 and an outer ring 5, and rolling elements of balls 6 held in a cage (not shown). The inner ring 4, outer ring 5, and balls 6 are each made of ceramic such as silicon nitride (Si ₃ N ₄ ).

The fixture 1 includes a pair of bushes 7a, 7b and twelve sleeve members 8 (8a to 8l).

The bushes 7a and 7b are annular bodies each made of the same metal material as the shaft 2 or a material having approximately the same coefficient of linear expansion. Butsuyu 7a,
7b has a tapered surface with one side 11 forming an angle α with respect to the centerline 12 of the shaft 2. The pair of bushes 7a and 7b have a tapered side surface 11 with a small diameter end 13 inside in the direction of the center line 12, and a large diameter end 14.
They are fitted onto the shaft 2 through a key 20, facing each other with the two sides facing outward.

On the other hand, the sleeve member 8 (8a to 8l)
It is made of the same ceramic material as or a material having approximately the same coefficient of linear expansion. Both side surfaces 15a and 15b of the sleeve member 8 (8a to 8l) each form a tapered surface forming an angle α with respect to the center line 12 of the shaft 2.
~8l) has side surfaces 15a and 15b with bushings 7a,
The sleeve member 8 (8a to 8l) is disposed around the shaft 2 in contact with the side surface 11 of the sleeve member 8 (8a to 8l).
All of them work together to form a virtual cylindrical body. The imaginary cylindrical body has both side surfaces tapered at an angle α with respect to the center line 12 of the shaft 2. As shown in FIG. 3, the angle α here is the diameter D at the center of the side surface 11 of the bushes 7a, 7b, and the diameter D at the center of the side surface 11 of the sleeve member 8 (8a to 8l).
When the distance in the center line 12 direction between the center portions of b is B, tanα=D/B.

[Operation] The operation when attaching the inner ring 4 of the radial ball bearing 3 to the shaft 2 using the fixture 1 having the above-described configuration is as follows.

Bushes 7a, 7b, 12 sleeve members 8a
After the fixture 1 consisting of ~8L is loosely assembled around the shaft 2, the inner ring 4 of the radial ball bearing 3 is fitted onto the outside of the fixture 1. At this time, a minute gap exists between the inner surface 18 of the inner ring 4 and the outer surface 17 of the sleeve members 8a to 8l. From this state, axis 2
When the nut 16 screwed into is rotated and the bush 7a is pushed in the direction of the center line 12 via the washer 19,
The sleeve member 8 is pinched by the bushes 7a and 7b.
a to 8l are pushed outward along the side surface 11,
The outer surfaces 17 of the sleeve members 8a to 8l and the inner surface of the inner ring 4 are in pressure contact with each other. In this way, the inner ring 4, sleeve members 8a to 8l, bushes 7a and 7b, and shaft 2 are integrally fixed.

Next, the operation of the fixture 1 during assembly and when the temperature changes will be explained.

As shown in FIG. 3, if the temperature change is T, this high temperature change causes the axis 2 to
Expands in the direction and radial direction.

Now, considering the combustion expansion at the center O of the side surface 11 of the bushes 7a, 7b, the displacement of the point O in the direction of the center line 12 due to the combustion expansion is given by the linear expansion coefficient of the shaft 2 and the bushes 7a, 7b being β, and the ceramic Since the linear expansion coefficients of the inner ring 4 and sleeve members 8a to 8l made of aluminum are extremely small, if this is ignored, then =βBT.

Here, B is both side surfaces 15a and 15 of the sleeve member.
This is the interval in the center line 12 direction of the center part of b.

Further, if the direct diameter of the center of the side surface 11 of the bushes 7a and 7b is D, the displacement in the radial direction of the point O due to combustion expansion is =βBT.

Therefore, as shown in the vector diagram in Figure 3,
The resultant displacement at point O is /=βDT/βBT=D/B=tanα.

In other words, by setting the angle of the tapered surfaces of the side surfaces 11 of the bushes 7a, 7b and both side surfaces 15a, 15b of the sleeve members 8a to 8l to tanα=D/B, the amount of increase due to fuel expansion in the semicircular direction is This will be canceled out by the amount of increase due to expansion in the direction,
The sleeve members 8a to 8l always maintain the same position in the radial direction, and the inner ring 4 will not be destroyed.

(C) Effects of the Invention As described above, according to the present invention, the displacement of the shaft in the radial direction due to the change in temperature can be canceled out by the change in the axial direction, and the state when the ring body is attached can always be maintained. , it is possible to reliably attach rings made of different materials with different combustion expansion rates to the shaft, and to obtain a shaft-to-ring attachment with a simple structure.

The above description has mainly been made regarding the embodiment in which the inner ring of a bearing is attached to the shaft, but in addition to this, the present invention also relates to a mounting tool for attaching a rotating ring of a mechanical seal or any other ring body to the shaft. It can be applied to

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view of the shaft and ring body fixture of the present invention, Fig. 2 is a cross-sectional explanatory view showing the arrangement relationship between the bushing, the sleeve member, and the ring body, and Fig. 3 is a side view of the bush. FIG. 6 is a vertical cross-sectional explanatory diagram showing displacement of the center point. 1... Mounting tool, 2... Shaft, 3... Radial ball bearing, 4... Inner ring, 5... Outer ring, 6... Ball, 7a,
7b...button, 8 (8a to 8l)...sleeve member, 11...side surface, 12...center line, 13...
...Small diameter end, 14...Large diameter end, 15a, 15b...
Both sides, 16...nut, 17...outer side, 18
...Inner side.

Claims (1)

[Claims] 1. Shaft mounting provided between the shaft and the ring body when fitting the ring body made of the second material onto the shaft made of the first material. The shaft mount includes a bushing and a plurality of sleeve members, the bushing being an annular body made of a material having substantially the same coefficient of linear expansion as the first material, and the bushing having a center line of the shaft. has a tapered surface forming an angle α with respect to one side thereof, and the tapered surface is fitted onto the shaft via a key with the tapered surface facing each other such that the small diameter end is located inside in the direction of the center line. , the plurality of sleeve members are made of a material having substantially the same coefficient of linear expansion as the second material, and are disposed between the shaft and the ring body with the side surfaces in contact with the side surfaces of the bush. The cylindrical body is concentric with the axis and has both side surfaces tapered at an angle α with respect to the center line of the axis, and the angle α is the angle α. A shaft and annular body characterized in that tanα=D/B, where D is the diameter of the central portion of the tapered surface of the bushing, and B is the distance between the central portions of both side surfaces of the sleeve in the center line direction. Mounting hardware.