JPS6083708A - Method for fixing sintered hard alloy ring to shaft in rolling roll - Google Patents

Abstract

PURPOSE:To fix a ring to a shaft with a high strength by heating and expanding a spacer whose outside circumferential part is gradually thicker than the inside circumferential part, fixing it to the shaft together with the ring and a disk spring, and cooling and contracting them. CONSTITUTION:Spacers 3, 5 are formed so that the outside circumferential part becomes gradually thicker than the inside circumferential part. The spacer 3 which is adjacent to a disk spring 2 is expanded by heating it to a prescribed temperature or above. Subsequently, the disk spring 2, the heated spacer 3, a sintered hard alloy ring 4, and the spacer 5 are installed in said order to a collar part 1a of a shaft 1, a nut 6 is screwed to a male screw part 1b, and it is clamped with a desired torque. Next, when the spacer 3 is cooled, the spacer 3 contracts along a tapered surface 4a of the ring 4, and a phenomenon by which it is displaced to the disk spring 2 occurs. In this way, a lateral pressure given to the ring 4, etc. by a disk spring 2 is raised.

Description

Detailed Description of the Invention The present invention relates to a rolling roll in which a cemented carbide ring (hereinafter referred to as a cemented carbide ring), a spacer, etc. are fixed to a shaft by side pressure using a nut, hydraulic nut, etc. , relates to a method of fixing a carbide ring to a shaft.

As is well known, in a rolling roll, a carbide ring, a spacer, etc. are inserted between fixing members of the shaft (shaft flange, nut, etc.) and are mounted together with the carbide ring, etc. There is a type in which a disk spring is deformed by the tightening force of a nut, etc., and a carbide ring, etc. is fixed by the elastic force of the disk spring. An example of a rolling roll of this type is shown in FIG. To explain the diagram,
Reference numeral IVi denotes a shaft, and this shaft 1 is provided with a collar portion 1a on the outer periphery of one end thereof, and a male screw portion 1b is formed at the other end. In this example, a disc spring 2, a first spacer 3, a carbide ring 4, and a second spacer 5 are mounted on the outer periphery of the shaft 1 in this order from the flange 1a side, and these are screwed into the male threaded part 1blC. It is tightened and fixed by a nut 6. By the way, in such a rolling roll, since the elastic force is generated in the disc spring 3 only by the tightening force of the nut 6, it is necessary to apply a sufficiently large force to the nut 6 to tighten it to the shaft 1. If it is difficult to support the shaft 1 in a rotationally stopped state, a problem arises in that the carbide ring or the like cannot be fixed to the shaft 1 with sufficient strength.

On the other hand, when a hydraulic nut is used instead of the nut 6 and the carbide ring 4 etc. is fixed, pressure oil is introduced into the hydraulic nut using a pressure oil supply device, and the carbide ring etc. is sandwiched between the nut. A structure is also used in which high lateral pressure is generated, and in this state, a split ring or the like is inserted between the hydraulic nut and the adjacent spacer to apply a sufficiently high lateral pressure to the carbide ring, etc., so that it can be fixed to the shaft. It is being However, such a rolling roll cannot be used unless it is equipped with an expensive pressure oil supply device.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a fixing method that can fix a carbide ring or the like to a shaft with sufficiently high strength even when fixing using a normal nut. do.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

In the present invention, when one or more carbide rings, spacers, and disk springs are mounted on the outer periphery of a shaft, and when these are sandwiched and fixed between fixing members fixed to the shaft, the spacer is fixed. At least one of them is a spacer whose outer circumference is gradually thicker than its inner circumference, and in a state where this spacer is heated and expanded, it is inserted into the shaft together with the carbide ring and the disk spring in a desired order. A fixing method characterized in that the carbide ring, disk spring, and spacer are inserted between the fixing members, and the amount of deformation of the disk spring is increased by cooling and contracting the expanded spacer. It is.

In applying the fixing method of the present invention, it is necessary to selectively set the thermal expansion characteristics and shape of the spacer that causes thermal expansion and contraction. The necessary conditions for setting these are the effective thickness of the spacer in a thermally expanded state, and, for example, the effective thickness of the spacer between the disk spring 2 and the carbide ring 4 adjacent to the expanded spacer 3 in the state shown in FIG. (thickness defining the axial distance) is smaller than the effective thickness in the contracted state.

This condition is based on the thermal expansion coefficient α of the material forming the spacer,
Inner diameter r1 and outer diameter r0 of the spacer, thickness tl of the inner peripheral part,
The thickness of the outer periphery t. , and the spacer temperature TH during heating,
The temperature TL of the spacer during use can be selected to satisfy the temperature, but usually the inner diameter r1 and the outer diameter r. and the temperature during use TII are determined by the applicable rolling rolls, so
The thickness tl of the inner circumference, the thickness 70 of the outer circumference, the heating temperature TH, and the material may be selected. By this, the difference Δt in the effective thickness of the spacer between heating and cooling can be set appropriately while satisfying the above conditions, and therefore the amount of deformation caused in the disk spring after fixation (in other words, , the amount of lateral pressure for fixation) can be determined.

Next, an example of a procedure for implementing the method of the present invention will be specifically explained with reference to FIGS. 1 and 2.

First, in mounting each member on the shaft 1, the spacer 3 to be placed adjacent to the disc spring 2 is heated to a predetermined temperature or higher to expand it. Next, the disk spring 2, the spacer 3,
The carbide ring 4 and spacer 5 are attached in this order, and the nut 6 is screwed into the male threaded portion 1b. In this state, when the nut 6 is tightened to the desired torque, the expanded spacer 3 will meet its inverted conical surface 3&, even though its inner diameter is larger than the outer diameter of the shaft. The conical shape of the ring 4 (tentatively named the Taber surface) 4a
are in contact with each other and positioned with respect to the axis of the shaft 1. At this time, the spacer 3 is in an expanded state as shown in FIG. 2, and has an effective thickness t between the disk spring 2 and the carbide ring 4. It has ff(H).

After the nut 6 is tightened, the spacer 3 cools and contracts, resulting in the state shown in FIG. 3 is slightly displaced toward the disk spring 2. Accordingly, the effective thickness t of the spacer 3 increases. t when rf(L) expands. ff(
Hl, the disc spring 2 has an effective thickness increase Δt(Δ””teff(L) t6ff(
H) ) 0 ), and the lateral pressure applied by this disc spring 2 to the carbide ring 4 etc. is increased.

Therefore, according to the method of the present invention, even when fixing the carbide ring 4 etc. to the shirt) 11C using an ordinary nut 6,
Compared to the conventional fixing method of just tightening the nut 6,
To identify a carbide ring or the like between the flange la of the shaft 1 and the nut 6 with high strength by generating a larger lateral pressure in the disc spring 2 after fixing when the nut 6 is tightened with the same torque. Can be done.

In the above example, a spacer that is expanded and contracted is placed adjacent to the disk spring 2, but the present invention is not limited to this example.

The present invention can also be applied to the case where a carbide ring or the like is fixed to a shaft IC using a hydraulic nut.

As explained above in detail, the present invention uses a spacer whose effective thickness during thermal expansion is smaller than the effective thickness during contraction when fixing a carbide ring etc. to a shaft, and allows this spacer to expand thermally. After the spacer is assembled into the shaft together with the carbide ring, disc spring, etc. and fixed with a nut, the spacer contracts, increasing the amount of deformation of the disc spring, and generating high lateral pressure on the disc spring. A carbide ring or the like can be fixed to the shaft with high strength without using nuts or the like. In addition, since the disk spring Id generates a large elastic force after cooling, when tightening the nut when the spacer expands, it is only necessary to apply a torque of the same level or less as in the past, and therefore the support of the roll during the tightening work is reduced. It has advantages such as ease of use.

[Brief explanation of the drawing]

1 and 2 are diagrams for explaining the present invention, in which FIG. 1 is a sectional view of the main part of the rolling roll showing the state when the spacer is contracted, and FIG. 2 is a sectional view of the main part of the spacer FIG. 3 is a cross-sectional view of the main part of the rolling roll showing the state when it is expanded. 1...shaft, la...tsuba f%, 1b...
... Male thread part, 2 ... Disc spring,
3...Spacer, 4...Cemented carbide ring, 6...Nut.

Claims (1)

[Scope of Claims] One or more cemented carbide rings, spacers, and disk springs are mounted around the outer periphery of a shaft, and these are sandwiched and fixed between fixing members fixed to the shaft. , at least one of the spacers is a spacer whose outer circumferential portion is gradually thicker than its inner circumferential portion 1. In a state where this spacer is heated and expanded, it is heated and expanded as desired together with the cemented carbide ring and disc spring. The cemented carbide ring, the disc spring, and the spacer are sandwiched between the fixing members, and the expanded spacer is cooled and contracted to increase the amount of deformation of the disc spring. A method for fixing a cemented carbide ring to a shaft in a rolling roll, characterized by: