JPH0673780B2 - Elastic pivot manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention is directed to manufacturing an elastic pivot which is interposed between a fixed body and a rotating body and which can accurately set a rotation phase of the rotating body with respect to the fixed body. Regarding the method.

<Prior Art> When it is necessary to accurately set the rotation phase of a rotating body pivotally attached to a fixed body, an elastic pivot that allows the rotating body to swing by elastic torsional deformation is provided. It is interposed between the fixed body and the rotating body.

For example, as shown in FIG. 3 showing an example of a reflected light scanning device that slightly changes the reflection direction of a light beam, a fork-shaped bracket 1 fixed to a frame (not shown) and a mirror to which a reflecting mirror 2 is attached. Holder 3 is elastic pivot 4
The mirror holder 3 is swingable with respect to the bracket 1 about the elastic pivot 4 within the allowable range of elastic torsional deformation. An upper end portion of an operation rod 5 attached to an actuator (not shown) is rotatably connected to the mirror holder 3 via a pin 6, and the mirror holder 3 swings around an elastic pivot 4 by the operation of the actuator. Works,
Since the mirror holder 3 is always loaded with the elastic torsion, the reflection direction of the light beam (not shown) can be changed accurately in correspondence with the operation amount of the actuator.

As shown in FIG. 4, as an example of the simplest structure of the elastic pivot, which is connected to the fixed body and the rotating body in this manner and can accurately set the rotation phase of the rotating body with respect to the fixed body. Has been.

As shown in FIG. 5 showing the disassembled state of the elastic pivot and FIG. 6 showing the sectional structure thereof, conventionally, an inner cylinder 101, an outer cylinder 102 into which the inner cylinder 101 is fitted, and an inner cylinder 101. A leaf spring 104 that is inserted into and welded to a first fitting groove 103 formed on the inner peripheral surface at 180 degrees apart from each other, and an inner cylinder that is 90 degrees out of phase with the first fitting groove 103. It is made by combining a pair of leaf springs 106, which are inserted into the second fitting groove 105 formed on the inner peripheral surface of 101 and welded. Recesses 107 are formed on both end sides of the outer peripheral surface with the center of the inner cylinder 101 as a boundary over approximately half a circumference, and these recesses 107 are separated from each other by 180 degrees.
Forms a gap 108 with the outer cylinder 102. These recesses 10
Both end portions in the circumferential direction of 7 are communicated with a pair of elongated holes 109 formed along the longitudinal direction of the inner cylinder 101, and the inner cylinder 101 and the outer cylinder 102.
After fitting and brazing the semi-arcuate joint 110, both ends thereof are cut off, and the long hole 109 remains as a part of the gap 108. After brazing, the outer cylinder 102
An annular groove 111 is engraved in the central portion of the so as to communicate with the gap 108.

<Problems to be Solved by the Invention> In the conventional method for manufacturing the elastic pivot, four parts are required, and moreover, the fitting groove, the recess, the long hole, and the like must be machined in the inner cylinder in advance. However, there is a problem that the cost of parts is significantly increased. Moreover, since the inner cylinder, the outer cylinder, and the leaf spring are welded or brazed to each other, deterioration of mechanical properties cannot be avoided, reliability is poor, and it is difficult to achieve uniform quality. . Further, there is a drawback that the number of working steps is very large, such as machining the annular groove after these joining operations and cutting off both ends.

An object of the present invention is to provide a method capable of easily and quickly manufacturing an elastic pivot from a single cylindrical member based on such findings.

<Means for Solving the Problems> A method of manufacturing an elastic pivot according to the present invention includes a cylindrical main body whose both ends are connected to a fixed body and a rotary body, and a central outer peripheral surface of the main body. An annular groove, a semicircular arc-shaped gap portion that is concentric with the main body and opens to one end surface of the main body and the annular groove, and a half opening concentrically with the main body to the other end surface of the main body and the annular groove. An elastic pivot comprising an arc-shaped gap portion and at least two leaf spring portions, both ends of which are integrally connected to the inner peripheral surface of the body, wherein the leaf spring portion is formed by wire-cut electric discharge machining on a cylindrical material. And the gap portion is formed into the cylindrical material by electric discharge machining with a semi-arcuate electrode plate, and then the leaf spring portions are separated from each other by electric discharge machining. To do.

<Operation> The annular groove is formed by cutting at the time when all the electric discharge machining is completed, or is formed before performing the wire cut electric discharge machining on the cylindrical material. Either the work of forming the leaf spring portion by wire cut electric discharge machining or the work of forming the gap portion by electric discharge machining may be performed first. Further, in parallel with the processing of this clearance, an extra leaf spring portion may be removed.

<Example> As shown in FIGS. 1 (a) to 1 (d) showing an example in which the manufacturing procedure of the elastic pivot according to the present invention is applied to the structure shown in FIG. 2, an annular groove 11 is formed on the outer peripheral surface of the central portion. Prepare a cylindrical material 12a previously formed by machining, etc., and make four small holes (not shown) through which the wire penetrates on the end surface of this cylindrical material 12a, and then wire cut discharge through the wire of the electrode here. Processing is performed to form a pair of leaf spring portions 13a and 13b that are formed by punching holes having a fan-shaped cross section in order and intersecting them at right angles.
At this time, the groove portion 14 corresponding to the long hole is also formed at the same time, but the groove portion 14 does not necessarily have to be formed, and the groove portion 14 is not necessarily formed.
When the groove 14 is formed, the groove portion 14 is in communication with the annular groove 11. Next, only the central portion of the one leaf spring portion 13a formed on the material 12b is left and both ends are removed to the portion of the annular groove 11 by electric discharge machining, and the other leaf spring 13b is left as a spring. Further, in the same procedure from the opposite side, the other leaf spring 13b
Leave one leaf spring part 13a intersecting at 90 degrees as a spring,
The portion of the other leaf spring portion 13b is removed up to the portion of the annular groove 11 by electric discharge machining. As a result, the crossed spring shown in FIG. 2 is obtained. Further, although this spring is integrated in the annular groove 11, the electric discharge machining tool is inserted and cut out from the communicating hole of the annular groove 11, and one leaf spring portion 13a and the other leaf spring portion are cut. 13b can be separated separately to form an independent cross spring. The material 12c thus obtained is used with a semi-circular plate-shaped electrode, and a semi-circular gap 15 is formed by electrical discharge machining from both end faces of the material 12c toward the annular groove 11, and the elastic pivot is formed. 16 Note that it is possible to perform the formation of the semicircular arc-shaped gap portion 15 and the removal of both end portions of the one leaf spring portion 13a at the same time with one electrode, and even when performing separately, this work procedure is reversed. You can

In the present embodiment, the case where two leaf spring portions are provided in one set has been described. However, as shown in FIG. 4 showing the structure of an example of the elastic pivot, it is also possible to form the leaf spring portions 106, 104, 106 with three sheets. In short, it suffices if at least two leaf spring portions are in an intersecting state. In this case, it is necessary to enlarge the communication hole for removing the inner leaf spring 104 by electric discharge machining.

<Effects of the Invention> According to the present invention, an elastic pivot can be obtained from a single cylindrical material, and it is possible to obtain a highly reliable elastic pivot while maintaining the maximum mechanical strength. Further, since most of the electric discharge machining is performed, the number of working steps is much smaller than that of the conventional one, and the elastic pivot can be easily and quickly manufactured.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 (a) to 1 (d) are conceptual views showing the manufacturing procedure of an embodiment of the present invention, and FIG. 2 (a) shows an elastic pivot which is the subject of the present invention. FIG. 2 (b) is a right side view, FIG. 3 is a perspective view showing an example of a reflected light scanning device, FIG. 4 is a cutaway view showing another example of an elastic pivot, and FIG. The figure is its exploded view, and FIG. 6 is its sectional view. In the figure, reference numeral 11 is an annular groove, 12a is a cylindrical material, 12b and 12c are materials, 13a, 13b and 17 are leaf springs, 15 is a gap, and 16 is an elastic pivot.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Eiichi Michioka 325 Kamimachiya, Kamakura City, Kanagawa Prefecture Mitsubishi Electric Corporation Kamakura Factory (72) Inventor Tadashi Segawa 325 Kamimachiya, Kamakura City, Kanagawa Mitsubishi Electric Corporation Kamakura Plant (72) Inventor Kazuaki Tajima 325 Kamimachiya, Kamakura City, Kanagawa Prefecture Mitsubishi Electric Co., Ltd.Kamakura Plant (72) Inventor Teruo Mori 325 Kamimachiya, Kamakura City, Kanagawa Prefecture Mitsubishi Electric Corporation Kamakura Plant (72) ) Inventor Eiichi Fujisawa 325 Kamimachiya, Kamakura City, Kanagawa Mitsubishi Electric Corporation Kamakura Factory (56) Reference JP-A-53-24200 (JP, A)

Claims (1)

[Claims] 1. A cylindrical main body having both ends connected to a fixed body and a rotating body, an annular groove formed in an outer peripheral surface of a central portion of the main body, and an end surface of the main body concentric with the main body. A semi-circular gap opening to the annular groove, a semi-circular gap opening concentrically with the main body to the other end surface of the main body and the annular groove, and both ends of the inner peripheral surface of the main body. An elastic pivot having at least two leaf springs integrally connected to the rod spring, the leaf springs being integrally formed on a cylindrical material by wire-cut electric discharge machining, and the gap portion having a semi-arc electrode. A method of manufacturing an elastic pivot, characterized in that the plate-shaped material is formed into a cylindrical material by electric discharge machining using a plate, and then the leaf spring portions are separated from each other by electric discharge machining.