JP2003009992A - Structure of locking headrest - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure of locking a headrest which promises a secure locking of a headrest without an angle close to 90 degrees in a locking groove formed on a headrest pole. SOLUTION: A pipe material 4 is used for the headrest pole to constitute the headrest, and a plurality of locking grooves 4a, 4b are formed on the pipe material 4 at prescribed intervals through a pressing process by a press. Each of the plurality of locking grooves 4a, 4b is made up of a flat bottom part 14, 22, a flat side surface 16, 24 substantially perpendicular to the bottom part 14, 22 at least at either side of the bottom part 14, 22, and an arc part 18, 26 continuing to the side surface 16, 24. A locking member 32 inserted into one of the plurality of the locking grooves 4a, 4b is formed into a flat plate. An angle of a locking part located on the locking member 32 which abuts on the bottom part 14, 22 of the locking groove 4a, 4b is made perpendicular.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock structure for holding a headrest at a desired position.

[0002]

2. Description of the Related Art FIG. 6 shows a conventional vehicle seat S, which includes a seat cushion 52 attached to a vehicle body,
A seat back 54 is attached to the seat cushion 52 so as to be tiltable, and a headrest 56 is attached to an upper end portion of the seat back 54 so as to be vertically movable.

As shown in FIG. 7, the headrest 56
Includes a cushion member 58 and a substantially U-shaped headrest pole 60 that supports the cushion member 58. Both leg portions 60a of the headrest pole 60 are detachably inserted into a pole guide 62 provided in the seat back 54. Has been done.

A plurality of lock grooves 64 for holding the headrest 56 at a desired height are formed on one outer peripheral surface of both legs 60a of the headrest pole 60 at predetermined intervals in the axial direction.

A solid round bar is generally used as the headrest pole 60, and the lock groove 64 is formed by cutting the round bar.

FIG. 8 shows one of the lock grooves 64, and a corner portion 64a of about 90 ° is formed on the upper portion of the lock groove 64 by cutting. Further, since the flat side surface portion can be sufficiently secured due to the presence of the corner portion 64a, a steel wire rod having a circular cross section (for example, a piano wire) is used as the lock member 66 which is fitted into the lock groove 64 and holds the headrest 56. Was enough.

[0007] Recently, since a round bar cutting process requires a lot of manufacturing steps, a method of using a pipe material for the headrest pole 60 and pressing with a plurality of punches to form the lock groove 64 has also been proposed.

[0008]

However, when the pipe material is pressed by the punch to form it, as shown in FIG. 9, an arc-shaped corner portion (drip portion) 64 is formed above the lock groove 64.
When b is generated and a large load is applied to the wire used as the lock member 66, the wire moves in the direction of the arrow,
Since it could be unlocked, it could not be used as a headrest locking structure.

The present invention has been made in view of the above problems of the prior art, and can reliably lock even if the lock groove formed in the headrest pole does not have a corner portion close to 90 °. It is intended to provide a lock structure for a headrest that can be.

[0010]

In order to achieve the above object, the invention according to claim 1 of the present invention is a headrest lock structure which is vertically movably attached to an upper end portion of a seat back. , A pipe material is used for a headrest pole that constitutes a headrest, and a plurality of lock grooves are formed at a predetermined interval in the pipe material by pressing with a press, and each of the plurality of lock grooves has a flat bottom surface portion,
A lock formed on at least one side of the bottom surface portion by a flat side surface portion formed substantially perpendicular to the bottom surface portion and an arc portion connected to the side surface portion, while being fitted into any one of the plurality of lock grooves. The member is formed in a flat plate shape, and the corner portion of the lock portion that abuts the bottom surface portion of the lock groove is formed at a right angle.

The invention according to claim 2 is characterized in that the length of the side surface portion is set to 40 to 60% of the depth of the lock groove.

Furthermore, the invention according to claim 3 is characterized in that an inclined portion is formed on the side opposite to the side surface portion.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a state in which a lock groove is formed in a headrest pole of a headrest having a lock structure according to the present invention, in which an anvil 2 is provided with a pipe material 4 cut to a predetermined length to be used as the headrest pole. The pipe material 4 is placed, and a plurality of lock grooves 4a and 4b are formed in the pipe material 4 by a plurality of punches 6 and 8 as lock groove forming tools.

In the example of FIG. 1, four punches 6 and 8 are used, and among the four punches 6 and 8, the punches 6 that form the three lock grooves 4a from the top of the pipe material 4 are the same. A punch 8 having a shape and for forming the bottommost lock groove 4b.
Has a different shape from the other punches 6.

As shown in FIG. 1, when the lock grooves 4a and 4b are formed in the pipe member 4, the punches 6 and 8 integrally held by the punch holder 10 are the punch guides 12.
It is inserted into the corresponding insertion holes 12a and 12b formed at equal intervals. A portion of the lower surface of the punch guide 12 that comes into contact with the pipe material 4 (a portion where the insertion holes 12a and 12b are formed)
Is an arcuate recess 1 having substantially the same shape as the contact portion of the pipe member 4.
2c is formed, and after the corresponding portion of the pipe material 4 is fitted into the arc-shaped recess 12c, the punches 6 and 8 are pressed against the pipe material 4 to form the lock grooves 4a and 4b.

Similar to the punch guide 12, an arcuate concave portion for accommodating the pipe material 4 is formed on the upper surface of the anvil 2 so that the pressure applied to the pipe material 4 can be dispersed by pressing.

After the plurality of lock grooves 4a and 4b are formed in the pipe material 4 cut into a predetermined length by using the punches 6 and 8, the pipe material 4 is bent as shown in FIG. ,
Used as a headrest pole.

Here, the shapes of the lock grooves 4a and 4b formed in the pipe member 4 will be described with reference to FIGS.

As described above, the pipe member 4 is formed with three lock grooves 4a having the same shape and one lock groove 4b having another shape below the lock grooves 4a.

The lock groove 4a has a flat bottom surface portion 14 formed by pressing the punch 6 and a bottom surface portion 14 above the bottom surface portion 14 as shown in the central cross section of the pipe of FIG. 4 (a).
A flat side surface portion 16 formed substantially perpendicular to the side surface portion, an arc portion (drip portion) 18 connected to the side surface portion 16, and a bottom surface portion 1
4 and the inclined portion 20 formed below.

On the other hand, as shown in FIG. 4 (b), the lock groove 4b has a flat bottom surface portion 22 formed by pressing the punch 8 and the bottom surface portion 22 above and below the bottom surface portion 22. It has a flat side surface portion 24 that is formed substantially vertically and an arcuate portion (drip portion) 26 that is connected to the side surface portion 24.

FIG. 5 shows one of the resin pole guides 28 attached to the seat back, and in particular, of both leg portions of the headrest pole (the pipe material 4 after molding).
It shows the pole guide 28 into which the leg portions having the lock grooves 4a and 4b are detachably inserted. The pole guide 28 has a circular hole 28a into which a leg portion of the headrest pole is inserted and an opening portion 28b into which a lock releasing knob described later is inserted, and the pole guide 28 is joined to a seat back frame (not shown). It is fixed by being inserted into a guide receiver (not shown).

The above-mentioned opening 28b is formed in the upper portion of the pole guide 28, and the unlocking knob 30 slidably attached to this opening 28b has an opening formed in the center. A flat plate-like lock member 3 having a portion 30a
2 are integrally formed. In addition, the opening 28b
Inside, a pair of coil springs 34 for urging the unlocking knob 30 in the pushing direction are provided.
Further, a long hole 28c is formed at one end of the lock member 32, and the pin 36 press-fitted into the hole 28d on the upper surface of the pole guide 28 is loosely inserted into the long hole 28c, whereby the opening portion of the pole guide 28 is opened. Knob 3 for unlocking from 28b
Preventing the departure of 0.

In the headrest provided with the headrest pole having the above-mentioned structure, the flat plate-shaped lock member 32 biased toward the headrest pole 4 by the coil spring 34 locks the bottom surfaces 14 and 22 of the lock grooves 4a and 4b. The upper and lower corners of the portion 32b are formed at right angles, and the lock portion 32b is retained (locked) at a desired position by being fitted into one of the lock grooves 4a, 4b.

When it is desired to increase the height of the headrest while the lock member 32 is fitted in any one of the three lock grooves 4a, when an upward force is applied to the headrest, the bottom surface of the lock groove 4a is applied. The lock member 32 in contact with the portion 14 slides on the inclined portion 20 against the biasing force of the coil spring 34. Therefore, when the headrest is lifted to a desired position and then the hand is released, the lock member 3 is released.
2 is fitted into any one of the other lock grooves 4a or 4b, and the headrest is held at that position.

However, when the lock member 32 is fitted in the lowermost lock groove 4b and an attempt is made to lift the headrest, an inclined portion is not formed below the lock groove 4b, and the lock member 32 is not formed. Contacts the flat side surface portion 24 formed below the lock groove 4b, so that the headrest is prevented from moving upward.

That is, this is the reason why the lowermost lock groove 4b of the headrest pole 4 is not provided with an inclined portion.
This is because the lock groove 4b acts as a stopper for preventing the headrest from coming off.

On the contrary, the lock member 32 has four lock grooves 4
Even if a downward force is applied to the headrest in a state where the lock member 32 is fitted in any one of the a and 4b, the lock member 32 contacts the flat side surface portion 16 or 24 formed above the lock grooves 4a and 4b. The headrest never touches down.

When it is desired to reduce the height of the headrest, when the knob 30 is pressed, the lock member 32 moves integrally with the knob 30 against the biasing force of the coil spring 34, and the lock is released. Next, when it is moved to a desired position and the hand is released from the knob 30, the lock member 32 is fitted into any one of the lock grooves 4a or 4b, and the headrest is held at that position.

As a matter of course, when the headrest is lifted while the knob 30 is pressed, the lock member 32 does not fit into the lowermost lock groove 4b, and the headrest can be separated from the seat back.

[0031]

[Example] As described above, when a wire having a circular cross section is used as the lock member when the lock groove has an arc-shaped corner (drip), the wire is locked when a large load is applied. In the present invention, a plate member is used as the lock member 32, and the shapes of the lock grooves 4a and 4b are variously changed to test whether or not the lock member can be reliably locked, because the lock member 32 may move in the releasing direction.

As a result, in the shapes of FIGS. 4 (a) and 4 (b), a pipe material having a diameter of 12 mm and a plate thickness of 1.6 to 2 mm is used, and the lock member 32 has a plate thickness of 1 to 1 mm.
When the length (b) of the bottom surface portions 14 and 22 of the lock grooves 4a and 4b is 1 to 2 mm using a 1.4 mm iron plate, the length (a) of the side surface portions 16 and 24 is the lock grooves 4a and 4b. In the range of 40 to 60% of the depth (d), the lock was reliably performed and passed the regulations of each country.

That is, since the lock member 32 is made of a plate material, the side surfaces 16, 24 of the lock grooves 4a, 4b are formed.
The contact area with can be increased, and the locking can be reliably performed.

The angle α of the inclined portion 20 shown in FIG. 4 (a) was set to about 20 °.

[0035]

Since the present invention is constructed as described above, it has the following effects. According to the first aspect of the present invention, a pipe material is used for the headrest pole, and a plurality of lock grooves are formed in the pipe material at predetermined intervals by press working by a press. Each of the plurality of lock grooves is formed by a flat bottom surface portion, a flat side surface portion formed on at least one side of the bottom surface portion substantially perpendicular to the bottom surface portion, and an arc portion connected to the side surface portion. Since the lock member that fits into one of the lock members is formed in a flat plate shape, and the corners of the lock portion that abut the bottom surface of the lock groove are formed at right angles, the contact area between the lock member and the side surface of the lock groove increases. However, the lock can be reliably performed.

Further, according to the second aspect of the invention, the length of the side surface portion is set to 40 to 60% of the depth of the lock groove, so that the predetermined contact area of the lock member with respect to the side surface portion of the lock groove is set. Can be secured, and the lock can be reliably performed.

Further, according to the invention described in claim 3,
Since the inclined portion is formed on the opposite side of the side surface portion, the headrest can be securely held at a desired position, and
The headrest can be lifted smoothly by applying an upward force.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a state in which a lock groove is formed in a headrest pole of a headrest provided with a lock structure according to the present invention.

2 is a front view of the headrest pole shown in FIG. 1. FIG.

FIG. 3 is a partially enlarged perspective view of the headrest pole shown in FIG.

FIG. 4 shows a lock groove formed in the headrest pole of FIG. 2, (a) is a longitudinal sectional view of one of the lock grooves,
(B) is another vertical cross-sectional view.

FIG. 5 is an exploded perspective view of a pole guide into which one of both legs of the headrest pole is inserted.

FIG. 6 is a perspective view of a conventional vehicle seat.

7 is a perspective view of a headrest attached to the seat of FIG.

8 is a cross-sectional view showing a relationship between a lock groove and a lock member having a circular cross section when a solid round bar used as a headrest pole constituting the headrest of FIG. 7 is cut.

9 is a cross-sectional view showing a relationship between a lock groove and a lock member having a circular cross section when a pipe material used as a headrest pole constituting the headrest of FIG. 7 is pressed.

[Explanation of symbols]

2 anvil 4 Pipe material 4a, 4b Lock groove 6,8 punch 6a, 8a protrusion 6b, 8b Relief part 6c slope 10 punch holder 12 Punch guide 12a, 12b Punch insertion hole 12c Arc-shaped recess 14,22 Bottom part 16, 24 Side part 18,26 arc part 20 Inclined part 28 Paul Guide 28a Headrest pole leg insertion hole 28b Knob insertion opening 28c Stopper insertion hole 28d pin press-fitting hole 30 Knob for unlocking 30a opening 32 Lock member 32b Lock part 34 coil spring 36 pin

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroyuki Ishikawa             1-14 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Delta             Industry Co., Ltd. F-term (reference) 3B084 DB04 DC02                 3B087 DC06

Claims (3)

[Claims] 1. A lock structure for a headrest, which is vertically movably attached to an upper end portion of a seat back, wherein a pipe material is used for a headrest pole that constitutes the headrest, and a plurality of locks are formed on the pipe material by pressing by a press. Grooves are formed at predetermined intervals, and each of the plurality of lock grooves is formed with a flat bottom surface portion, a flat side surface portion formed on at least one side of the bottom surface portion substantially perpendicular to the bottom surface portion, and the side surface portion. A lock member that fits into any one of the plurality of lock grooves is formed in a flat plate shape, and a corner portion of the lock portion that abuts the bottom surface of the lock groove is formed at a right angle. The lock structure of the headrest is characterized by the above. 2. The lock structure for a headrest according to claim 1, wherein the length of the side surface portion is set to 40 to 60% of the depth of the lock groove. 3. The lock structure for a headrest according to claim 1, wherein an inclined portion is formed on the side opposite to the side surface portion.