JPS59218218A - Method and device for manufacturing circular arcuate t-shaped joint - Google Patents

Abstract

PURPOSE:To manufacture comparatively easily a circular arcuate T-shaped joint having a high accuracy by performing a bulge working to a circular arcuate pipe blank material obtained by cutting an annular or circular arcuate pipe having a prescribed curvature, and cutting the tip of a projecting part formed on the side face of this base material. CONSTITUTION:For instance, a circular arcuate pipe 11 is formed by bending a straight pipe material 8 by means of roll forming, etc., and it is cut to a pipe blank material 12 of a prescribed size, and thereafter, a projecting part 12a is formed by performing a bulge forming working to the blank material 12. Subsequently, a T-shaped joint 13 having a circular arcuate blank material body 12b is obtained by cutting the tip of this projecting part 12a. In this case, the blank material 12 is cut from an annular or circular arcuate pipe material 11 which holds easily the surface shape in a circle of a high accuracy and is bent in a state that it remains long. Accordingly, as for the blank material 12, the accuracy of a section shape is good, a good roundness is obtained, and also a shape of a size of the whole containing not only the section shape but also the circular arcuate shape of the body 12b can be kept in a high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a manufacturing method and manufacturing apparatus that can relatively easily manufacture an arcuate T-shaped joint with high precision.

FIG. 1 shows an example of an automobile steering wheel, which has a structure in which a boss plate 2 connected to a steering link shaft 1 and a wheel 5 consisting of a main ring 3 and a sub-ring 4 are connected via spokes 6. The T-shaped joint 7 used to connect the wheel 5 and the spokes 6 must have an arcuate portion into which the wheel 5 is fitted.

Fig. 2 explains the conventional manufacturing method of such an arcuate T-shaped joint, in which a straight pipe material 8 is cut to obtain a pipe material 9 of a predetermined length, which is then subjected to T-shaped bulge forming. Processing was performed in the following steps: forming the protrusion fffiQa, then performing secondary processing of bending the material body 9b and cutting the tip of the protrusion 9a, and finally removing the filler material used to shape the bulge 1. . However, according to this method, the cross-sectional shape of the material body 9b tends to become elliptical as shown as 8 in FIG. 2 due to the bending process. It is difficult to obtain the same degree of accuracy as the circular cross section of the inserted member, and furthermore, in the case of an asymmetrical T5 in which the direction of the protruding portion 9a is not perpendicular to the material body 9b, the dimensional accuracy may be reduced. Securing was a factor. 9) There was a problem in that it became an IF.

The present invention has focused on this point, and has been made for the purpose of relatively simple manufacturing of an arcuate T-shaped handle with high precision. A method for manufacturing an arc-shaped T-shaped joint, which comprises performing bulge forming on an arc-shaped pipe material obtained by cutting it to size, forming a protrusion on the side surface of the pipe material, and then cutting off the tip of the protrusion. The present invention also provides an apparatus for manufacturing an arcuate T-shaped joint by this method.

This manufacturing equipment has an arc-shaped material groove in which the pipe material is set and a bulge forming groove branching from this material groove, and the mold is divided into parts to enable material supply and processing droplet discharge. a press mechanism that drives the movable side of the mold; a pair of arc-shaped punches for bulge forming inserted from both ends of the material groove of the mold; A rack and pinion mechanism connects a pair of punch holders that move the punch along an extended line of The punch holder drive mechanism is characterized by comprising a punch holder drive mechanism that is driven in an arc shape to apply pressure for bulge forming by a pair of punches.

That is, in the present invention, as shown in FIG. 3a, a straight pipe material 8 is bent by roll forming or the like to form, for example, an annular pipe material 11, which is then shaped into a circular arc shape of predetermined dimensions as shown in FIG. After cutting the pipe material 2, the pipe material 12 is subjected to bulge forming to form a protrusion 12a as shown in Figure 3C, and the tip of the protrusion 12a is cut to form a shape as shown in Figure 3D. T having an arc-shaped material body 12b
5 joint 13 is obtained, and the arc-shaped pipe rope material 12 is
In order to cut the pipe material 11 into an annular or arc-shaped pipe material 11 which has been bent while being long so that it is easy to maintain a highly accurate circular cross-sectional shape, the cross-sectional shape is cut as shown as 13 in FIG. The shape has good accuracy and roundness, and since bulge forming is performed by applying high internal pressure, the overall shape and dimensions, including not only the cross-sectional shape but also the arc shape of the material body 12b, can be adjusted. This makes it possible to maintain high accuracy. Therefore, as shown in FIG. 3e, the protrusion 12
Even in the case of an asymmetrical T-shaped joint 13 where a is inclined with respect to the material main body 12b, highly accurate processing is possible.

The present invention can be applied to any type of T5 joint made of metal or other material that can be formed into a bulge.In addition to the filling method, bulge forming can be performed using various methods such as those using hydraulic pressure and electric discharge forming. It is possible to adopt

Next, an embodiment of the manufacturing apparatus shown in FIGS. 4 and 5 will be described.

In the figure, reference numeral 21 denotes a mold consisting of an upper mold 21a and a lower mold 521b, and the dividing surface has an arc-shaped material groove 22 and a bulge forming groove 23 branched from this material groove 22.

The upper W21a is driven up and down by a press ram (not shown), and when the press ram is at the top dead center, it rises to a position where material can be supplied, cured, and processed droplets can be discharged. Both ends of the material groove 22 and the end of the bulge forming groove 23 of the mold 21 are open to the side surface of the mold 21. 25.26 is a pair of bulge forming punches, 27.28 is a punch 25.2
6, and the punches 25, 26 and punch boulders 27 and 28 are in the material groove 22.
The punch boulders 27 and 28 are shaped like an arc located on an extension of the arc of the holder guide 29.30.
The punches 25 and 26 are supported so as to be movable along the extended line of the arc of the material groove 22, and the punches 25 and 26 move in accordance with the movement of the punch holder 27 and 28, and the punches 25 and 26 move into the material groove 22. The amount of insertion is changed. 3
This is a drive mechanism for the 1 Lt/' inch holder 27.28, and is composed of a cam 32, a rack 33, gears 34.35 and 36.37, and the like. The cam 32 is attached to a press ram and moves up and down in conjunction with the press ram, and a slide surface 32a inclined at 45 degrees is formed at the lower end, and this slide surface 32a is also inclined at 45 degrees. The rack 33 is in pressure contact with the sliding surface 33a of the rack 33.The rack 33 is supported by a guide plate 38 (thus, teeth are formed on both sides of the gear 34) so that the rack 33 can be moved horizontally by being pushed by the cam 32. and gear 36 are in mesh with each other.

Gear 35.37 meshes with this gear 34.36, G1,
These gears 35 and 37 further mesh with teeth formed on the inner side and pocket of the internal gear type number/N6 inch holder 27 and 28.

The apparatus is constructed as described above, and - 21a as follows:
is pressed against the lower mold 21b. Pressure control of the mold press is performed using a pressure control plate 40 made of urethane material, for example. At the same time as this mold holding, the cam 32 descends,
This lowering is carried out by the rack 3 by the sliding surfaces 32a and 33a.
As the rack 33 moves to the left in the figure, the punch holder 27 is driven counterclockwise via the gear 34.35, and the gear 36.3 is also driven counterclockwise via the gear 34.35.
7, the punch holder 28 is driven clockwise.

As a result, the punches 25 and 26 are press-fitted into the material groove 22 at the same time, and pressure is applied to the material 12 through the low melting point alloy to perform bulge forming. .2 is formed. In addition, each gear 34
~37 have the same diameter, the cam 32 rises, and the rack 33
is moved to the right in the figure as the cam 32 rises by an appropriate return mechanism (not shown), and the operation is reversed to the movement when the cam 32 is lowered to discharge the amount of machining droplets, and the operation is completed. The movement of each member is shown in the figure by an open arrow when pressurizing, and by a hatched arrow when returning. The tip of the protrusion 12H is cut using gold 4.
After being discharged from 121, another process (not shown) is carried out. Furthermore, this device can also process straight T-shaped joints in which the main body part of the material is not arc-shaped but straight by changing the mold and punch. Furthermore, either symmetrical or asymmetrical T-shaped joints can be applied by changing the shape of the mold.

As is clear from the above description, the present invention performs 80 bulge forming operations on an arc-shaped pipe material obtained by cutting a circular or arc-shaped pipe material.
It is possible to efficiently manufacture an arcuate T-shaped joint with high precision in cross-sectional shape and overall shape using relatively simple and compact equipment. In addition, in the apparatus of the present invention, bulge forming is performed by simultaneously applying DO pressure from both sides using a pair of punches, so the plastic flow during bulge forming becomes stable.
From this point of view, there is also the effect that the quality of the T21 joint is the same as above.

[Brief explanation of the drawing]

Fig. 1 is a schematic plan view of an automobile steering wheel using a T-type joint, Fig. 2 is a diagram showing the processing procedure according to the conventional manufacturing method, and Fig. 3 fal to tel shows the processing procedure according to the manufacturing method of the present invention. 4 is a plan view of a main part of an embodiment of the manufacturing apparatus of the present invention, and FIG. 5 is a side view of the same. 11... Annular (arc-shaped) pipe material, 12...
Arc-shaped pipe material, 12a... protrusion, 12
b...Material body, 13...T-type joint, 21
... Mold, 21a... Upper mold, 21b... Lower mold,
22...Material 1 caustic, 23...Bulge forming groove,
25.26...Bulge forming punch, 27.28
... Punch holter, 31... Drive mechanism, 32.
...Cam, 33...Rack, 34-37...Gear.

Claims (2)

[Claims] (1) An annular or arc-shaped pipe material with a predetermined curvature is cut into a predetermined size, and a bulge-forming process is applied to the arc-shaped pipe material, and a protrusion is formed on the side surface of the pipe material. A method for manufacturing an arcuate T-shaped joint, characterized by cutting off the tip. (2) A mold that has an arc-shaped material groove in which the pipe material is set and a bulge forming groove branching from this material groove, and allows material supply and processing discharge by being a split mold; A press mechanism that drives the movable side of the Hungki mold, a pair of arc-shaped punches for bulge forming that are inserted from both ends of the material groove of the mold, and a pair of arc-shaped punches that hold each of the punches and extend the arc of the material groove. A rack and pinion mechanism connects a pair of punch holders that move the punch along a line, a press mechanism that drives the mold, and the pair of punch holders, and moves the punch holder in an arc shape in conjunction with the press mechanism. A punch holder drive mechanism that is driven to apply +J mouth pressure for bulge forming using a pair of punches.