JP2001225112A - Method for manufacturing coned disc spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost of a product. SOLUTION: A flat steel belt for springs 1 is circularly bent into an annular shape by passing through between rolls 2-4 and, when approximately one round is completed, cut with a cutter 8. Subsequently, in a state where mutual end parts are abutted, the abutting part is joined by welding. The annular base stock 9 for coned disc springs which has been obtained in this way is heated to a prescribed temperature and tapered with a forming jig J. Because a coned disc spring is manufactured from a wire in this way, the material yield is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a disc spring.

[0002]

2. Description of the Related Art A conventional method of manufacturing a disc spring is, for example, shown in FIG.
It was as shown in FIG. First, a flat spring steel material 3
From 0, punch into a circle by pressing. From the punched circular material 31, a small diameter punch is further concentrically performed. Thus, the obtained flat plate ring member 32 is formed into a truncated conical cylindrical shape by press working. After that, it is quenched, tempered, austempered, etc., and the distortion caused by this heat treatment is corrected by a jig.
Thereafter, processing such as shot peening is performed as necessary, thus obtaining a disc spring having predetermined spring characteristics.

[0003]

However, in the above-mentioned manufacturing method, a ring-shaped disc spring is obtained by punching from a flat plate. For this reason, there is a problem that the yield of the material is extremely low and the product cost is increased. The present invention has been developed to meet such a demand, and an object of the present invention is to provide a method of manufacturing a disc spring having a low product cost.

[0004]

According to a first aspect of the present invention, there is provided a flat belt spring steel material which is fed out, bent into an annular shape, cut into a predetermined length, and then connected to each other. Is fixed by welding to form a flat plate ring, and then formed into a truncated conical cylindrical shape having a tapered surface from the inner peripheral side toward the outer peripheral side to obtain a disc spring having predetermined spring characteristics. Is what you do. According to the invention of claim 2, a continuous flat band spring steel material is formed into a truncated conical cylindrical shape having a tapered surface from an inner peripheral side toward an outer peripheral side by a bending jig while being bent into an annular shape. Thereafter, the plate spring is cut into a predetermined length, and the ends are fixed to each other by welding to form a truncated conical cylindrical shape, thereby obtaining a disc spring having predetermined spring characteristics. Further, according to the invention of claim 3, a continuous flat band spring steel material is fed out, bent into an annular shape, cut into a predetermined length, and then pulled in a direction in which the end portions are brought closer to each other, so that the whole is from the inner circumferential side to the outer circumferential side. It is characterized in that it has a truncated conical cylindrical shape having a tapered surface toward the side, and in this state, the ends are fixed to each other by welding to obtain a disc spring having predetermined spring characteristics.

[0005]

The disc spring obtained by the method according to any one of the first to third aspects of the present invention is made of a flat strip of spring steel. Can be improved.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.
As flat band spring steel materials, for example, SWRH82A, SK
5, SK5M, etc., can be used, and a material that is continuously fed from a material obtained by winding these in a roll shape is sequentially processed in the following manner.

<First Embodiment> FIGS. 1 to 3 show a first embodiment of the present invention. The flat band spring steel material 1 described above is
First, it is passed between three forming rollers 2 to 4, where it is bent in an annular shape. Each of the forming rollers 2 to 4 can rotate independently of each other.
Are sent between them, so that they rotate in the direction of the arrow shown in the figure. As shown in FIG. 3, a bending guide 6 and a pair of cutters 5 and 8, which will be described later, are arranged further downstream of the forming roller 4 located at the most downstream side (see FIG. 3). Although the bending guide 6 is not shown in detail, a guide hole for guiding the passage of the flat band spring steel material during bending is provided through the side surface. They are formed with approximately equal height dimensions. Further, an upper guide 7 for guiding the distal end portion of the flat spring steel material 1 upward is disposed at a position downstream of the bending guide 6 and near each of the forming rollers 2 to 4. The upper guide 7 has an upwardly inclined surface 7a, and guides the tip of the flat spring steel material 1 upward along the inclined surface 7a so as not to interfere with the flat spring steel material 1 being bent. And guide it in a spiral upward. The cutters 5, 8 are fixed blades, one of which is disposed above the bending guide described above, and the other 8 is a movable blade which is disposed on the side of the bending guide and below the flat band spring steel material and is capable of moving up and down. It is. Immediately after the tip of the flat band spring steel material 1 spirally turned through the upper guide 7 passes through the bending guide 6, the lower cutter 8 rises, and the flat band spring steel The steel material 1 is cut by shearing. In the product A thus obtained, the end portions slightly overlap each other vertically. The reason why the ends are overlapped in this way is to secure in advance a length range lost by melting when the ends are electrically welded in the next step.

In the welding step, the overlapping end portions are butted together, and the butted portions are welded (butt welding, laser welding, etc.) to obtain an endless disc spring material 9. Next, an annealing process is performed on the disc spring material 9, and thereafter, burrs generated by welding are removed by trimming or the like.

The deburred disc spring material 9 can be quenched and tempered if strength is particularly required.
Heat treatment such as austempering is performed. Then, after being heated to about 400 ° C., it is set on a molding jig J (heating may be performed after setting on the molding jig). The molding jig J has a pair of jig pieces 10 and 11 that can be tightened by bolts 12 and nuts 13. A flat part having a diameter smaller than the center hole of the disc spring material 9 is provided on the upper surface of the lower jig piece 10. An inclined surface 10b having a predetermined downward slope is formed along the entire circumference, and the lower surface of the upper jig piece 11 is substantially aligned with the upper surface of the lower jig piece 10. It is formed so that it can be fitted.

The disc spring material 9 is mounted in a state in which a plurality of disc spring materials 9 are stacked on the lower jig piece 10, and the upper jig piece 11 is set in this state, and both jig pieces are set with bolts 12 and nuts 13. Tighten 10 and 11. As a result, a predetermined pressure acts on each disc spring material 9, so that each disc spring material 9 has a tapered surface 9 a that descends from the inner peripheral side to the outer peripheral side according to the gradient of the inclined surface 10 b. . As a result, a ring-shaped disc spring 14 having predetermined spring characteristics is obtained from each disc spring material 9. Finally, depending on the application, processing such as shot peening and low-temperature annealing is performed to obtain a final product. Note that shot peening is a process for improving the durability of the disc spring 14, and low-temperature annealing is a process performed for the purpose of removing distortion generated by shot peening.

According to the manufacturing method of Embodiment 1 described above, since the disc spring 14 can be manufactured from a wire rod of a flat band spring steel material, it can be used for punching from a flat plate material having a large area as in the related art. The material yield can be increased in comparison. Further, it has been confirmed that the disc spring 14 manufactured by the method of the present embodiment can obtain good spring characteristics as in the related art. In the present embodiment, the tapered surface 9a is formed by the forming jig J after the austempering process. However, after the tapered surface 9a is formed by a cold press or the like, the austempering process is performed, and then the purpose of removing distortion is provided. Then, the fastening by the jig J may be performed.

Second Embodiment FIGS. 4 and 5 show a second embodiment of the present invention. In the first embodiment described above,
After the disc spring material 9 was manufactured, a tapering operation was performed. In the second embodiment, the tapering step is incorporated in the spirally turning step.

As shown in FIG. 4, on the downstream side of the forming roller 4, an illustration 2 for tapering the flat band spring steel material 1 is shown.
The two bending jigs 15A and 15B are arranged at appropriate intervals. In the bending jig 15, straightening paths 16A and 16B are formed so as to penetrate along the feeding direction of the flat band spring steel material 1 therein. As shown in the drawing, the correction path 16 is formed so as to be substantially horizontal at the upstream side 15A, but is formed so as to form a predetermined gradient at the downstream side 15B. That is, the flat band spring steel 1 is twisted between the bending jigs 15A and 15B, and after passing through the downstream bending jig 15B, a desired gradient is obtained in the flat band spring steel 1. After that, it is cut by the cutter 8 through the upper guide 7, and the ends are welded together. As in the first embodiment, the obtained material is subjected to processes such as austempering, shot peening, low-temperature annealing, and strain relief as necessary.

According to the method of Embodiment 2, it is possible to obtain the disc spring 14 having the same spring characteristics as the conventional one while improving the yield of the material.

In the second embodiment, the flat band spring steel material 1 is twisted and tapered between the two bending jigs 15A and 15B. However, as shown in FIG. Alternatively, tapering may be performed in the process of passing through No. 15. That is, the straightening path 16 formed to penetrate the bending jig 15 shown in FIG. 6 corresponds to FIGS. 7A to 7C.
As shown in the figure, the bending gradient gradually increases along the feed direction of the flat band spring steel material 1. Thus, the flat band spring steel material 1 is straightened so as to gradually increase the degree of bending in the course of passing through the straightening path 16 of the bending jig 15, and when passing through the straightening path 16, a desired gradient set is obtained. Have been obtained. Further, the tapering method is shown in FIG.
This can also be achieved by the following. 8, two bending jigs 15C and 15D are formed by a pair of rollers. That is,
The flat belt spring steel material 1 is passed between the two rollers while being pinched, and the two roller shafts of the bending jigs 15C and 15D which are located on the upstream side are substantially horizontal. The roller 15D located on the downstream side has both roller shafts arranged with a predetermined gradient.

<Third Embodiment> FIGS. 9 to 12 show a third embodiment of the present invention. That is, in the present embodiment, when the flat band spring steel material 1 is bent in an annular shape, the steel strip 1 is cut off at a time before forming a complete annular shape. That is, also in the third embodiment, FIG.
Is used as it is, but cutters 5, 8
Is earlier than in the first embodiment. For this reason,
Those cut out by the cutters 5, 8 are in a ring-open state in which the ends are separated from each other and a predetermined angle range is open.

Next, as shown in FIG. 9, the ends are sandwiched by a pair of clamp electrodes SP1 and SP2 in a butt welding machine, respectively, and both clamp electrodes are moved closer in the direction of the arrow shown in FIG. As a result, the flat band spring steel material 1 in the ring-opened state is deformed so that the peripheral surface forms a tapered surface, as shown in FIG. And flat belt spring steel material 1
When the two clamp electrodes SP1 and SP2 are energized in a manner as shown in FIG. 11 in a state where the ends are brought into contact with each other, the ends are joined to obtain a closed truncated conical cylinder D1 ( See FIG. 12). As in the case of the first and second embodiments, processes such as austempering, shot peening, low-temperature annealing, and strain removal are performed on the obtained ones as needed. According to the method of Embodiment 3,
A coned disc spring having the same spring characteristics as the conventional one can be obtained while improving the material yield. In particular, in the present embodiment, since the tapered process only requires pulling the cut flat band spring steel material, the structure of the entire process is simplified compared to the case where a special jig for tapering is required. An effect that can be obtained is also obtained.

[Brief description of the drawings]

FIG. 1 is a process chart showing a first half of a manufacturing process according to a first embodiment.

FIG. 2 is a process diagram showing the second half of the same.

FIG. 3 is a perspective view showing a step of making an annular turn.

FIG. 4 is a plan view showing a part of a manufacturing process according to a second embodiment.

FIG. 5 is a perspective view of a bending jig.

FIG. 6 is a perspective view showing another embodiment of the bending jig.

FIGS. 7A, 7B, and 7C are cross-sectional views taken along line XX, line YY, and line ZZ of FIG. 5, respectively.

FIG. 8 is a perspective view showing still another embodiment of the bending jig.

FIG. 9 is a perspective view showing a state where a flat band spring steel material cut out in the manufacturing process of the third embodiment is sandwiched by clamp electrodes.

FIG. 10 is a perspective view showing a state where the ends are butted to each other.

FIG. 11 is an explanatory view showing a welding process.

FIG. 12 is a perspective view showing a manufactured disc spring.

FIG. 13 is a conventional manufacturing process diagram.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Flat band spring steel material 2-4 ... Roll 8 ... Cutter 9 ... Disc spring material J ... Molding jig

Claims (3)

[Claims] 1. A continuous flat band spring steel material is fed out, bent into an annular shape, cut into a predetermined length, and the ends are fixed to each other by welding to form a flat plate ring. And forming a conical spring having a predetermined spring characteristic by shaping the shape into a truncated conical cylinder having a tapered surface. 2. A continuous flat band spring steel material is fed out and bent into an annular shape, and is formed into a truncated conical cylindrical shape having a tapered surface from an inner peripheral side to an outer peripheral side by a bending jig. A method of manufacturing a disc spring, characterized in that the disc spring having a predetermined spring characteristic is obtained by cutting into lengths and fixing the ends to each other by welding to form a truncated conical cylindrical shape. 3. A continuous flat band spring steel material is fed out, bent into an annular shape, cut into a predetermined length, and then pulled in a direction in which the end portions approach each other, so that the whole is directed from the inner peripheral side to the outer peripheral side. A frusto-conical cylindrical shape having a tapered surface, and in this state, the ends are fixed to each other by welding to obtain a disc spring having predetermined spring characteristics.