JP3373953B2 - Method and apparatus for manufacturing support rod - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support rod that holds a headrest mounted on the upper part of a seat of an automobile so that it can be moved back and forth and is held in a predetermined position, or a handle portion is connected for a hand brake. The present invention relates to a method and an apparatus for manufacturing a support rod to be applied.

[0002]

2. Description of the Related Art Conventionally, a supporting rod for a headrest or a hand brake has a plurality of engaging recesses formed in a solid solid bar material and is engaged with an engaging projection provided on a seat or a vehicle body. In addition to being freely movable, it was able to move forward and backward so that it could be securely hooked at a desired position.

The support rod which can be hooked and retracted is a milling cutter or the like on the outer peripheral surface of a solid metal rod, which is gradually cut inward from the outer peripheral surface. Since a plurality of hook recesses having a predetermined shape are formed, it takes a certain amount of time to cut the hook recess having a predetermined shape and depth with respect to the solid bar material. The blade portion of a cutter or the like has a drawback that it requires correction work and dress-up every predetermined number of cutting processes.

In addition, innumerable irregularities, burrs and the like are generated in the retaining recesses of the support rod formed by cutting with a cutter, and there is a drawback that polishing work is required after cutting, or a solid solid body. By cutting the bar material on the outer peripheral surface side, there is also a drawback that the cutting point occurs in the fiber flow of the internal structure in the outer peripheral surface side material of the solid bar material and the strength of the support bar is reduced. Was there.

Although the weight of the supporting rod for headrest or handbrake occupies tens of thousands of parts in an automobile, the weight reduction of each of the tens of thousands of parts can improve the performance of the automobile and improve fuel efficiency. There is a great demand to reduce the weight of connected automobiles, and instead of using solid solid bar material as the material of the support rod, hollow pipe material that can reduce the weight of the support rod is used. Some of the materials are now available.

However, when the hooking recess is formed by engraving the support rod made of a pipe material, the milling cutter does not cut the entire thickness of the pipe material but leaves a part of the inner surface of the pipe. Since it was cut with, it is necessary to strictly control the cutting amount from the outer peripheral surface side, or the cutting point of the fiber flow occurs in a considerable portion of the material thickness and causes the strength of the support rod to decrease, When using hollow pipe material as the material for the support rod, it is necessary to change the material of the pipe material to one with high strength, and as a result, the support rod becomes expensive, so use pipe material as the material. Was limited to some.

[0007]

SUMMARY OF THE INVENTION According to the present invention, when a hooking recess is formed in a supporting rod, the working time and cost are reduced, sufficient strength is achieved, and the weight of an automobile member is reduced. The manufacturing method and the manufacturing apparatus are provided.

[0008]

SUMMARY OF THE INVENTION The present invention is based on the above-mentioned prior art. In view of the problem that the machining time is long and the machining cost is high in the cutting by the milling cutter, the punch is pressed against the outer peripheral surface of the pipe material. By pressing and forging the latching recess, the latching recess is formed by a single vertical movement of the punch, thereby performing a simple process.

In view of the problem of reduction in strength due to cutting of fiber flow, the pipe material is moved by press working, that is, the plastic material is bulged to form a corresponding amount of the retaining recess on the inner peripheral surface of the pipe material. The strength of the fiber is prevented from decreasing by maintaining the continuous state of the fiber flow over the entire length, and the solid bar material has a weight, and the pipe material used in some parts requires an expensive material. in view of the problems, use by a press forging accompanied by plastic flow of the above, along with make available a lightweight pipe material, the pipe material of ordinary material to prevent strength reduction in a continuous and work hardening of the fiber flow In addition, the pad at the location where the locking recess is formed is
After inserting a small diameter pipe material inside the pipe material,
By pressing it, the above problems are not solved.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings . As shown in FIGS. 1 and 2, 1 is a support rod for a headrest, and straight portions 2, 2a of the support rod 1 are shown. Have a plurality of retaining recesses 3, 3a ... Indented, and the supporting rod for the hand brake is the same as the linear portion 2, 2a of the supporting rod 1 for headrest having the retaining recesses 3, 3a. It is a composition.

Next, the straight portions 2 and 2a of the supporting rod 1 shown in FIG.
, The hooking recesses 3, 3a provided in the pipe member 4 are provided at predetermined positions on the outer peripheral face 5 of the pipe member 4 from the outer peripheral face 5 of the pipe member 4 to a part of the material 6.
Is formed by plastically flowing to the inner side of the pipe material 4, and the plastic flow portion 7 bulges and moves toward the inner peripheral surface 8 side of the pipe material 4.

Therefore, an example of the shapes of the retaining recesses 3, 3a ... And the plastic flow portion 7 will be described. The outward appearance of the retaining recesses 3, 3a. The shape is the same as that of the conventional one except for the material structure of the surface, and the shape of the pipe material 4 is different from the continuous material 6 of the solid pipe material 4 before processing. The plastic flow portion 7 bulged on the peripheral surface 8 side has substantially the same shape and thickness as the retaining recesses 3, 3a ... And is in a continuous state.

Next, the method and apparatus for manufacturing the support rod according to the present invention will be described . As shown in FIG.
Reference numeral 0 denotes a fitting groove provided in a lower mold 21 for holding a substantially lower half of the pipe material 4 which is a material of the support rod 1, and similarly to the lower mold 21, an upper mold 23 covers substantially the upper half of the pipe material 4. Fitting groove 22
And the fitting groove 2 located on the contact surface of the upper and lower molds 21 and 23.
The reference numerals 0 and 22 are substantially circular, and the inner diameters of the fitting grooves 20 and 22 are substantially the same as the outer diameter of the pipe member 4 and are substantially the same.

Further, through holes 24, 24a ...
And the through hole 2
A plurality of punches 25, 25a, ... each having a predetermined shape are arranged through 4, 24a so as to be vertically movable.

The lower end shape of the punches 25, 25a ...
As shown in FIG. 3, the locking recesses 3, 3a ...
Punches 25, 25a ...
The front surface or the rear surface of the lower end of the lower surface is a rising forming surface 26, a part of the lower end surface is a bottom forming surface 27, and the remaining part of the lower end surface is a slope forming surface
8 respectively.

The lower die 21 is provided with guide pins 29, 29a, and the upper die 23 is formed with sliding holes 30, 30a, through which the guide pins 29, 29a. , Upper mold 23 is lower mold 21
The punches 25, 25a, ... Are vertically controlled with respect to the upper die 23 or the lower die 21.

Then, the pipe member 4 is placed on the lower mold 21 so that the lower half of the pipe member 4 is fitted into the fitting groove 20 of the lower mold 21, and the upper mold 23 provided with the fitting groove 22. Are dropped from above to cover the entire circumference of the pipe material 4, and the punches 25, 25a, ... arranged in the through holes 24, 24a of the upper mold 23 are moved downward to bring the punch 25 to the outer peripheral surface 5 of the pipe material 4. , 25a ... are pressed.

Due to such press pressing, the material 6 at a predetermined portion of the pipe material 4 generates plastic flow, and the plastic flow portion 7
Moves so as to bulge toward the inner peripheral surface 8 side of the pipe material 4, and the hooking recesses 3, 3a ... Are depressed in the outer peripheral surface 5 of the pipe material 4 to bulge on the inner peripheral surface 8. The plastic flow portion 7 is continuous with the solid pipe material 4 in the front-rear direction and the circumferential direction with a substantially same thickness, that is, the plastic flow portion 7 is the front-back material 6 of the pipe material 4.
And the fiber flow becomes continuous.

Further, in the above manufacturing method, the upper and lower molds are provided with fitting grooves 20 and 22 having substantially the same size as the outer diameter of the pipe member 4 in relation to the shapes of the retaining recesses 3, 3a ... Although the case where 21 and 23 are used has been described, such fitting grooves 20 and 22 are not particularly necessary.

For example, if the outer peripheral surface 5 of the pipe material 4 and the fitting grooves 20 and 22 of the upper and lower molds 21 and 23 are not substantially the same shape, or if the upper and lower molds 21 and 23 without the fitting grooves 20 and 22 are used, 4 is held, when the punches 25, 25a ... Are pressed and pressed, the plastic flow of the material 6 forms the retaining recesses 3, 3a. Inner surface 8
Not only in the direction, but also in the directions of both sides of the hooking recesses 3, 3a ..., Some outward bulges occur and the circular shape is partly collapsed, but after mounting on the automobile, no serious problem occurs in use.

Although the pipe material 4 has been described as having the same thickness over the entire length, the shape of the pipe material 4 can be changed as follows, and the punches 25, 25a ... Although the case where the pipe material 4 is held only by the upper and lower molds 21 and 23 has been described, the press pressing method can be changed in relation to the wall thickness of the pipe material 4.

For example, although it depends on the diameter of the pipe member 4 and the shape and depth of the hooking recesses 3, 3a, ...
When the wall thickness of the material 6 of FIG.
The rising portions 9 of ... Are not formed vertically, and there is a tendency for sagging, but the vertical shape and the outer peripheral surface 5 of such rising portions 9 are large.
To maintain the right angle of the corners with and is shown in FIG.
As described above, when the small-diameter pipe material 15 is previously inserted into the inside of the pipe material 4 and pressed at the places where the hook recesses 3, 3a ... Are formed, the total thickness of the pipe material 4 and the small-diameter pipe material 15 is reduced. The pipe material 4 serving as the base material on the outer peripheral side and the small-diameter pipe material 15 serving as the auxiliary material on the inner peripheral side have the circular portion and the retaining recesses 3 and 3a.
The forming parts of ... Are molded in similar shapes.

[0023]

Further, the hook recesses 3, 3a provided on the support rod 1 ...
Although the shape of the rising portion 9, the bottom portion 10 and the guiding inclined surface 11 has been described, the shape is not limited to such a shape, and FIG.
As shown in FIG. 6 (b), for example, the bottom portion 10 is not flat, and a recess having a sharp angle may be provided, and the shape of the hooking recesses 3, 3a ... Is provided on the vehicle body side or the seat side. The shapes of both of them can be appropriately changed in relation to the shape of the hooking protrusion (not shown) that is formed.

[0025]

In summary, according to the present invention, the punches 25, 25a ... Are pressed against the outer peripheral surface 5 of the pipe material 4 to form the recessed recesses 3, 3a. The material 6 of the pipe material 4 at the portion corresponding to the depression of the hooking recesses 3, 3a ....
Since the plastic flow portion 7 is plastically flowed to form the plastic flow portion 7 on the inner peripheral surface 8 of the pipe member 4, it is possible to swell the pipe member 4 in one step by pressing the punches 25, 25a. .. can be formed, once the punches 25, 25a are set in the upper mold 23, the depth setting of the hook recesses 3, 3a .. The vertical movement of 25a ... makes it a simple work, and the machining time can be shortened, and the machining cost can be reduced. Moreover, since the tool to be used is the punch 25, 25a, the punch 25, 25a
The dressing frequency of ... is much less than that of the dressing up of the cutter, and the work efficiency can be improved, and by changing the punches 25, 25a ..., the hooking recesses 3, 3a of various shapes can be ... Can be formed.

Further, by pressing the material 6 by the plastic flow, the material 6 at the location where the retaining recesses 3, 3a ... Are bulged and formed on the inner peripheral surface 8, so that the retaining recesses 3, 3a of the support rod 1 are formed. ... The smoothness of the surface is maintained at the outer peripheral surface 5 of the pipe material 4 which is the material, and burrs and the like do not occur in the hooking recesses 3, 3a, and the pressing work that was conventionally necessary is eliminated and pressed. It can be commercialized as the support rod 1 for the headrest or the brake handle in the processed state, and the manufacturing cost can be reduced.

Further, according to the above-mentioned manufacturing method, the hook recesses 3,
The material 6 corresponding to the depression of 3a is bulged and formed on the inner peripheral surface 8 of the pipe material 4, and the material 6 including the formation portions of the hooking recesses 3, 3a is made continuous and has substantially the same wall thickness. Since the support rod 1 can be manufactured, the plastic flow portion 7 of the pipe material 4 at the location where the retaining recesses 3, 3a ... Are formed is in a continuous state with the surrounding material 6, so that the fiber flow of the internal structure of the material. Therefore, even if the material of the supporting rod 1 is a hollow pipe material 4, the strength can be sufficiently maintained, and in the press working having such a plastic flow portion 7, the hooking recesses 3 and 3a. ... and its surroundings are subjected to plastic strain, and as a result, work hardening occurs on the surfaces of the hooking recesses 3, 3a ... And on the corners of the hooking recesses 3, 3a. As the seat rises, the seat-side or car-body-side hooking protrusion and hooking recess 3 3a ... or hooking withdrawal of such rising portion 9 is performed frequently, the operating force, even when an external force acts, it is possible to prevent to strength retention deformation of both the semi-permanent.

In addition, since the supporting rod 1 has sufficient strength by the above manufacturing method, the pipe material 4 can be used as the material of the supporting rod 1, and therefore the supporting rod 1 is hollow because the inside thereof is hollow. 1, the weight of the vehicle can be reduced, that is, the driving performance can be improved and the fuel consumption can be improved. Further, compared with the conventional case, the material is not deleted at the place where the hook recesses 3, 3a ... Are formed. In addition to having the plastic flow part 7 and having sufficient strength by causing work hardening, the material of the pipe material 4 as a raw material does not need to have a special high strength,
It can be a normal one and can prevent the material cost from rising.

Further , the diameter, the wall thickness and the hooking recess of the pipe member 4
3,3a ... of the ultra-thin pipe material 4 in relation to the shape, depth, etc.
It is difficult to adopt, but it is necessary to form the hook recesses 3, 3a ...
Inside the pipe material 4 in the place
After pushing it, the punches 25, 25a ...
Even if the Yip material 4 is extremely thin, a hooking recess having a desired shape
3, 3a ... can be formed, and the hooking recesses 3,
Round tubular thin pipe with high strength except for the formation of 3a ...
Since the material 4 can be used, the weight of the whole supporting rod 1
The amount can be further reduced.

In the invention according to claim 2, a pipe material
4 in the upper and lower molds 21, 23 in the fitting grooves 20, 22,
Hold them so that their surfaces are substantially aligned, and form the hooking recesses 3, 3a ...
Since it is configured to be formed,
To prevent the material 6 from bulging in the circumferential direction of the pipe material 4,
Both sides of the retaining recesses 3, 3a ... Maintain the circular state of the pipe material 4.
Can be held, and therefore the same length of pipe material 4
It is possible to maintain the circular condition of one diameter and to assemble the car.
To improve the external appearance later, or to other members when assembling
It is possible to prevent the harmful effects of
It will be.

[0031]

[Brief description of drawings]

FIG. 1 is a perspective view of a support rod for a headrest.

FIG. 2 is a plan view of a support rod having a hook recess.

FIG. 3 is a side view of FIG. 2 with a punch arranged.

FIG. 4 is an enlarged cross-sectional view of a main part of a linear portion of a support rod.

FIG. 5 is an enlarged cross-sectional view of a main part of another embodiment.

FIG. 6 is a perspective view of a main part of a support rod showing hook recesses of various shapes.

FIG. 7 is a perspective view of upper and lower molds according to the present invention.

[Explanation of symbols]

1 support rod 3, 3a ... Hook recess 4 Pipe material 5 outer peripheral surface 6 materials 7 Plastic flow part 8 inner surface 9 Rising part 15 Small pipe material 20 Mating groove 21 Lower mold 22 Mating groove 23 Upper mold 24, 24a… Through hole 25, 25a ... Punch

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-31350 (JP, A) JP-A-5-309424 (JP, A) JP-A-61-2232022 (JP, A) JP-A-57- 9549 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21D 53/88 A47C 7/38 B21D 22/02 B21J 5/02

Claims (3)

(57) [Claims] 1. A small-diameter pipe material is internally provided in the pipe material.
Then , the punch is pressed against the outer peripheral surface of the pipe material at the portion where the small-diameter pipe material is located to form a recessed recess on the outer peripheral surface of the pipe material, and the pipe material at a portion corresponding to the recessed recess. Plastic flow of the above material to bulge the plastic flow part on the inner peripheral surface of the pipe material and
A method for manufacturing a support rod, characterized in that the support rod is formed into a shape similar to that of the ip material . 2. A pipe material is provided in a fitting groove provided in upper and lower molds,
2. The method of manufacturing a support rod according to claim 1, wherein the inner and outer peripheral surfaces are held so that the inner and outer peripheral surfaces substantially match with each other to form a hooking recess. 3. Use in the method for manufacturing a support rod according to claim 2.
It is a manufacturing device, and on the upper and lower contact surfaces that are controlled to move up and down,
A support characterized in that a fitting groove having substantially the same size as the pipe material to be processed is provided, a through hole reaching the fitting groove is provided in the upper die, and a punch that is vertically controlled is arranged in the through hole. Rod manufacturing equipment.