JP3373952B2 - 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 supporting rod to be given.

[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 support rod, the weight of the member is reduced as an automobile member, the strength is sufficient, and the processing cost is reduced. It is intended to provide a supporting rod that is

[0008]

SUMMARY OF THE INVENTION The present invention is based on the above-mentioned prior art. In view of the problem of strength reduction due to cutting of a fiber flow in cutting with a milling cutter, the pipe material is moved by press working, that is, plastic flow. By forming a bulge corresponding to the hooking recess on the inner peripheral surface of the pipe, a continuous state of the fiber flow is maintained over the entire length of the pipe material to prevent a decrease in strength.

Further, in view of the problems that a solid bar material has a weight and a pipe material used in part requires an expensive material, by performing press forging with plastic flow as described above, Lightweight pipe material can be used, and the hook recess
At the formation point of the
The above problem is not solved by making a small-diameter pipe material internally .

[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 according to the present invention, and a straight line of the support rod 1. A plurality of retaining recesses 3, 3a ... Are depressed in the portions 2, 2a, and the support rod for the hand brake is provided with retaining recesses 3, 3a.
a straight portion 2 of the support bar 1 for headrest, which has a ...
It has the same structure as 2a.

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 plastically formed on the inner side of the pipe member 4, and the plastic flow portion 7 bulges toward the inner peripheral surface 8 side of the pipe member 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 manufacturing method and the manufacturing apparatus of the support rod will be explained . As shown in FIG.
Lower mold 21 for holding substantially the lower half of the pipe material 4 which is the material of
And a fitting groove 22 for covering substantially the upper half of the pipe member 4 is provided in the upper mold 23 as in the lower mold 21, and the fitting groove is located on the contact surfaces of the upper and lower molds 21 and 23. 20 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 have a slightly larger diameter.

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 ...
The 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 shape of the hooking recesses 3, 3a ... Provided in the support rod 1 has been described as the rising portion 9, the bottom portion 10 and the guiding inclined surface 11, but the shape is not limited to such a shape, and FIG. ) And FIG. 6 (b), for example, the bottom portion 10 is not flat, and a sharp-angled depression may be provided, and the shape of the hooking recesses 3, 3a ... Is 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) provided. Further, when the support rod 1 is manufactured, by adopting a press-pressing forging process having a plastic flow portion 7 capable of maintaining strength, the pipe material 4 can be locked in one step by pressing the punches 25, 25a .... Since the recesses 3, 3a ... Can be formed, once the punches 25, 25a ... Are set in the upper mold 23, it becomes almost unnecessary to control the depth setting of the hook recesses 3, 3a. Is a simple work due to the vertical movement of the punches 25, 25a, and the machining time can be shortened, and the machining cost can be reduced, and the tools to be used are the punches 25, 25a. The frequency of dressing up the punches 25, 25a ... is much less than that for dressing up the cutter, and work efficiency can be improved. Also, by changing the punches 25, 25a ..., various shapes can be hooked. The recesses 3, 3a ... Can be formed.

[0025]

In summary, according to the present invention, in the support rod 1 in which the engaging recesses 3, 3a ... Are formed on the outer peripheral surface 5 of the pipe member 4, the pipe material is provided with a large amount of the material 6 corresponding to the depression of the engaging recesses 3, 3a. 4 is made to bulge on the inner peripheral surface 8 and the material 6 including the places where the hooking recesses 3, 3a ... Are formed is in a continuous state and has substantially the same thickness, so that the hooking recesses 3, 3a ... Pipe material 4
Since the plastic flow part 7 is in a continuous state with the surrounding material 6, the fiber flow of the internal structure of the raw material is also in a continuous state, so that even if the raw material of the supporting rod 1 is the hollow pipe material 4, the strength is sufficient. Can be held at the same time, and in the press working having such a plastic flow part 7, the locking recesses 3, 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 a result of the rising, the latching protrusions on the seat side or the vehicle body side and the latching disengagement of the rising portions 9 of the latching recesses 3, 3a, etc. are frequently performed, and even when an operating force or an external force is applied, both The deformation can be prevented and the strength can be maintained semipermanently.

Further, the material 6 for forming the hooking recesses 3, 3a ...
Is swelled on the inner peripheral surface 8 and is pressed by plastic flow of the material 6, so that the smoothness of the surface of the retaining recesses 3 and 3a of the supporting rod 1 The outer peripheral surface 5 is maintained as it is, no burrs or the like are generated in the retaining recesses 3, 3a, and the like, which does not require the polishing work that has been necessary in the past, and the supporting rod for the headrest or the brake handle in the pressed state. 1
Can be commercialized as, and the manufacturing cost can be reduced.

Further, the support rod 1 which forms the retaining recesses 3, 3a.
Since the pipe material 4 is used as the material of the above, the weight of the support rod 1 can be reduced by the amount of the hollow interior, that is, the weight of the automobile can be reduced to improve the driving performance and the fuel consumption. In comparison with the above, in order to have a plastic flow part 7 without removing material at the place where the hooking recesses 3, 3a are formed and to have sufficient strength by causing work hardening,
The material of the pipe material 4, which is the material, does not need a special high-strength material, and can be a normal material, so that the material cost can be prevented from rising.

Further, the diameter, wall thickness and 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 ...
At the place, a small diameter pad with a similar shape is
Since the pipe material 15 is incorporated, the pipe material 4 is extremely thin.
Even if it exists, form the hooking recesses 3, 3a ... With a desired shape
And it is strong except for the places where the hooking recesses 3, 3a ...
It is possible to use thin pipe material 4 with a high circular cylindrical shape.
In order to come, it is possible to further reduce the weight of the support bar 1 as a whole.
I can.

According to the second aspect of the invention, the hook recess is formed.
During plastic deformation of 3, 3a ... Both sides of the retaining recesses 3, 3a.
Direction, which prevents the pipe material 4 from bulging in the circumferential direction,
Both sides of the retaining recesses 3, 3a ... Maintain the circular state of the pipe material 4.
Since it is held, the diameter of the pipe 4 is the same throughout the length.
The circular state of can be maintained, and after assembling the car
To improve the external appearance and to prevent adverse effects on other members during assembly.
It is possible to prevent harm and its practical effects are enormous.
It is a thing.

[0030]

[0031]

[Brief description of drawings]

FIG. 1 is a perspective view of a support rod for a headrest according to the present invention.

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.

[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 15 Small pipe material

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-5-309424 (JP, A) JP-A-6-31350 (JP, A) JP-A-57-9549 (JP, A) JP-A-61- 232022 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21D 53/88 A47C 7/38 B21D 22/02 B21D 39/04 B21J 5/02

Claims (2)

(57) [Claims] 1. A support rod in which a hooking recess is formed on the outer peripheral surface of a pipe material, in which a large amount of material corresponding to the depression of the hooking recess is bulged and formed on the inner peripheral surface of the pipe material, and the hooking recess forming portion is formed. Made of a material containing
Separately similar shape to the inside of the pipe material at the location where the recess is formed.
Support rod characterized by having a small diameter pipe material inside . 2. The support rod according to claim 1, wherein both sides of the hooking recess hold the circular state of the pipe material.