JPH0536355B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for assembling a pantograph jack, particularly in a pantograph jack, in which a threaded portion or a shaft portion of a threaded rod engages in the axial center portion of the pantograph jack. A method of assembling a threaded rod engaging body having a rod engaging hole, that is, a nut body having a screw rod engaging screw hole or a metal body having a threaded rod supporting hole, and the ends of a pair of upper and lower groove-shaped links. It is.

[Conventional technology]

This type of assembly method includes, for example, Jikosho.
As shown in Publication No. 55-46718, the threaded rod engaging body has a three-stage structure having a head, a large diameter shaft portion with a threaded rod engaging hole, and a small diameter tip portion, and has an upper and lower groove shape. One side wall or shaft diameter adjustment hole is provided at the end of the link, and a tip engagement hole or a shaft engagement hole and a tip engagement hole are provided in the other side wall, and the threaded rod engagement body is formed into a groove-shaped link. After extending between both side walls through the shaft engagement hole and tip engagement hole, a flange stopper is formed on the end of the tip through plastic working, and the end of the upper and lower groove-shaped link is It is known to assemble the both side walls of the shaft and the threaded rod engaging body so that the former can rotate around the large diameter shaft and small diameter tip of the latter.

[Problem that the invention seeks to solve]

The above-mentioned known assembly method was proposed with the main purpose of reducing manufacturing costs and increasing strength, but from the viewpoint of the three-stage diameter structure of the threaded rod engagement body,
It is difficult to reduce the production cost, and
In order to ensure the strength of the small-diameter tip, it must be formed from a piece of bar with a large cross-sectional area.Therefore, it is difficult to reduce material costs and weight, and at least one side wall of the groove-diameter link is difficult to reduce. Since the inner surface is not subjected to any movement restraints, it tends to be displaced inward and has a problem of lacking stability.

[Means for solving problems]

According to the present invention, the above problem can be solved by inserting a threaded rod engaging body having the same diameter over the entire length between both side walls of the ends of the upper and lower groove-shaped links, and inserting the fitting holes formed in the both side walls at both ends. in a state where the part protrudes outward, and in this state, on each of the adjacent parts of the inner and outer surfaces of the ends of both side walls of the upper and lower groove-shaped links of the threaded rod engaging body,
This problem is solved by a method of assembling a vantagraph type jack in which a plurality of stop protrusions are pressed at intervals around the shaft and upper and lower groove type links and a threaded rod engaging body are assembled.

[Effect]

In this invention, the threaded rod engaging body is assembled in the form of a rod piece having only a threaded rod engaging hole,
While inserted into the insertion holes at the ends of the upper and lower groove-shaped links, inner and outer stopper protrusions that sandwich both side walls of the groove-shaped links from the inside and outside are formed by press processing using a press mold, thereby forming a double-grooved link. The threaded rod engaging body is assembled so that the former can rotate around the axis of the latter but cannot move in the axial direction.

〔Example〕

This invention can be implemented, for example, in the manner shown in the drawings.

First, a threaded rod engaging body 12 (here, a nut body having a threaded hole 14 that engages with a threaded portion of a threaded rod) constituted by a round bar piece with the same diameter over the entire length is attached to the ends of a pair of upper and lower groove-shaped links 20 and 26. A state in which the screw rod is inserted into the insertion holes 24 and 30 formed in both side walls 22 and 28 of the part and has a diameter slightly larger than the diameter of the threaded rod engaging body 12, so that both ends protrude outward between the both side walls. Go out and hand it over.

Next, in the first press machine, after holding the threaded rod engaging body 12 through the central part with the upper and lower groove-shaped links 20 and 26 substantially overlapped on the inside and outside, the shaft of the threaded rod engaging body 12 is inserted from both ends thereof. A pair of left and right press dies 32 movable in the direction are operated concentrically. This press mold 32 is used for the threaded rod engaging body 12.
tooth-shaped protrusions 36 that protrude inwardly within the diameter of the threaded rod engagement body 12 on the inner periphery thereof, having a circular center hole 34 larger than the diameter of When moving along the threaded rod engaging body 12, the molded protrusion 36 comes into contact with the corresponding outer peripheral part of the threaded rod engaging body 12, moving the material thickness of the part inward and caulking it. Outer stop protrusions are provided at both ends of the threaded engagement body 12 adjacent to the outer surfaces of both side walls 28 of the lower groove link 26 located on the outer side of the pair of upper and lower groove links, at intervals of 90° around the axis. 16 is molded.

Subsequently, in a second press machine, both grooved links are overlapped so as to extend almost horizontally, and
After holding the threaded rod engaging body 12 through both ends,
Threaded rod engaging body 1 between both side walls 22 of upper groove-shaped link 20 located inside inserted into threaded rod engaging body 12
A pair of upper and lower rectangular press molds 38, which are vertically movable, are opposed to each other and act from the upper and lower parts of the press mold 2.
Each press mold 38 has a molded protrusion 4 at each corner that can abut against the front and rear parts of the threaded rod engaging body 12 adjacent to the inner surfaces of both side walls 22 of the upper channel link 20.
0, and the front and rear portions of the threaded rod engaging body 12 adjacent to the inner surfaces of both side walls 22 of the upper channel link 20 are An inner stop protrusion 18 is formed on the inner stop protrusion 18.

After this, the threaded rod engaging body 12 was rotated 90 degrees around the axis to change its front and rear positions to the upper and lower positions, and then a pair of upper and lower press molds 38 were approached from above and below in the same way as above, and the previously formed Inner stop protrusions 18 are molded on the new front and rear parts with an interval of 90° from the inner stop protrusions 18.

〔Effect of the invention〕

As described above, according to the present invention, there is no need to perform any processing other than the threaded rod engaging hole in advance on the threaded rod engaging body, and the inner and outer stop protrusions to be formed later can be easily formed by press working. Therefore, manufacturing costs are low, and sufficient strength can be ensured even if the threaded rod engaging body is formed of bars with a relatively small cross-sectional area, so material costs and weight can be reduced. Further, according to the present invention, the stop projections on both side walls of the upper and lower groove-shaped links suppress the displacement of the threaded rod engaging body in the axial direction, thereby providing an effect of high stability.

[Brief explanation of the drawing]

FIG. 1 is a front view of the main parts of an embodiment of a pantograph-type jack assembled by the method of the present invention;
2 is a side sectional view substantially taken along the - line in FIG. 1, FIG. 3A is a partially cutaway side view showing the form of the external stop protrusion, and FIG. 3B is a side sectional view taken along the - line arrow in FIG. 3A. FIG. 4A is a front view showing how the inner stop protrusion is formed, and FIG. 4B is a side view showing how the inner stop protrusion is formed. 10... Threaded rod, 12... Threaded rod engaging body, 16
...Outer stop projection, 18...Inner stop projection,
20... Channel link, 22... Side wall, 24... Fitting hole, 26... Channel link, 28... Side wall, 30
...Fitting insertion hole, 32...Press mold, 38...Press mold.

Claims (1)

[Claims] 1. A threaded rod engaging body having the same diameter over its entire length is extended between both side walls of the ends of the upper and lower groove-shaped links, with both ends protruding outward through insertion holes formed in the both side walls. In this state, a plurality of stop protrusions are press-processed at intervals around the axis on the adjacent inner and outer surfaces of both side wall ends of the upper and lower groove-shaped links of the threaded rod engaging body, thereby forming the upper and lower groove-shaped links. How to assemble a pantograph type jack by assembling a threaded rod engaging body.