JPH069526B2 - Headrest front / rear adjustment device for automobile seats - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a headrest front-rear adjusting device for a vehicle seat.

(Prior Art) Conventionally, a headrest mounted on an upper part of a seat back of an automobile can be adjusted to an optimum position according to a sitting posture of an occupant. The one described in Japanese Laid-Open Patent Publication No. 57-52863 is known.

(Problems to be Solved by the Invention) In the headrest front-rear adjusting device described above, the headrest is locked or unlocked when the adjustment is completed by a ratchet and a pawl member that engages with and disengages from the ratchet. Therefore, the adjusting device is of a stepped adjustment type that adjusts in stages.

Therefore, since the minimum adjustment range is determined by the pitch between the ratchet teeth of the ratchet, there is a risk that it may not be possible to set it at a desired position.

In this case, the amount of movement of the headrest can be kept small by reducing the pitch from the ratchet teeth to the ratchet teeth, so some measures can be taken.However, ratchet teeth can be supported to some extent from the point where the claw members mesh with each other. There was a limit to how small the pitch could be.

For this reason, for example, an adjustment device consisting of a pinion gear with a brake and a reverse rotation prevention mechanism and a rack that can be steplessly adjusted forward and backward by an operation unit provided outside the headrest has already been commercialized. However,
This is not desirable because the structure is complicated and the operation part with a feeling of protrusion is located on the side of the headrest. Moreover, it is not preferable in terms of appearance, and it is difficult to operate in the sitting posture.

Therefore, according to the present invention, the structure is simple, the operation portion is not exposed to the outside, and the operation can be easily performed in the sitting posture and the adjustment can be performed steplessly. It is an object of the present invention to provide a headrest front / rear adjustment device for a seat.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention relates to a seat having a headrest provided on an upper portion of a seatback, and is fixed to a seatback side in a headrest body of the headrest. A supported base bracket, a guide body that is supported by the base bracket so as to be movable back and forth, and is fixedly supported on the headrest body side, and a guide body that is slidably penetrated by the guide body and is in a locked posture inclined from the axis of the guide body. A through hole is provided that acts on the peripheral surface of the guide body to allow forward movement and prevent rearward movement, while allowing it to slide forward and backward away from the peripheral surface of the guide body in a substantially vertical free posture. The locking member, the urging means for urging the locking member to keep it in the locked position at all times, and the locking member in the locked position when the headrest main body moves to the forefront And then, and a switching means that the lock posture from the free attitude at the time of the rearmost movement of the headrest body.

(Operation) In such a headrest adjusting device, when the head is pressed against the headrest body, the locking member in the locked posture prevents the rearward movement, so that the restrained state is obtained.

Next, move the headrest body forward with your hand in the sitting position and release the hand to adjust the position of the headrest in a stepless manner, so that you can set the optimum position. In this case, in order to move the headrest body that has returned too far forward to the rear, move the headrest body to the most front position, return the locking member to the rearmost position in the free posture, and then move it to the front again. This makes it possible to adjust the position.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to the drawings of FIGS. 1 to 8.

In FIG. 3, reference numeral 1 denotes a seat back of a seat, and a headrest 3 is provided above the seat back 1.

The headrest 3 is composed of a pair of left and right holding members 7 and 7 serving as a main frame of the headrest main body 5, a plate plate 9 connecting the holding members 7 and a holding member 7 and a skin 11 enclosing the plate plate 9 and a headrest. On the left and right sides of the main body 5, there are rod-shaped guide bodies 1 extending in the front-rear direction.
3 and 13 are supported at both ends by the holding member 7 and 7.

A box-shaped base bracket 15 and a locking member 17/17, which are long in the left and right and open upward, are slidably penetrated through the guide members 13 and 13, respectively, and a through hole 19 of the locking member 17 is formed in the guide member 13. The diameter is set larger than the shaft diameter.
Therefore, as shown in FIG. 7, the locking member 17 has the through hole 1
It becomes possible to incline by a predetermined angle by the play allowance of 9.

The base bracket 15 is integrally fixed to the left and right support stays 21 and 21 which are extended to the outside through a long hole 9a which is provided on the headrest body 5 side and which is long in the front-rear direction and which is fixedly supported by the seat back 1 so as to be vertically movable. Has been done. Mounting portions 15a and 15 formed on the left and right of the base bracket 15
One end of the first biasing spring 23 is locked to a. The other end of the biasing spring 23 is locked to the plate plate 9. As a result, the headrest body 5 is always biased to the rear position (right side in FIG. 4).

The locking member 17 has a predetermined thickness a secured by stacking several plates, and is arranged inside the base bracket 15.

As described above, the diameter of the through hole 19 of the locking member 17 is set larger than the shaft diameter of the guide body 13. Further, the locking members 17 and 17 are inclined in a lock posture I (movement of the second biasing springs 25 and 25 and the switching means 27 and 27) to prevent the movement toward the front and the movement toward the rear (solid line in FIG. 7). ) And almost vertical free posture that can slide back and forth II
(Solid line in FIG. 8).

The second biasing spring 25 is a coil spring wound in a coil shape, one end of which is locked to the base bracket 15 and the other end of which is locked to the mounting hole 17 a at the upper end of the locking member 17, respectively. As a result, the inclined lock posture I in which the through hole 19 acts on the peripheral surface of the guide body 13 is secured.

Further, below the guide body 13, the locking member 1 in the lock posture I
A fixed rod 29, both ends of which are fixed to the base bracket 15, is in contact with the rear surface side (right side in FIG. 7) of the No. 7. Therefore, when the headrest main body 5, that is, the guide body 13 is moved rearward (arrow B in FIG. 7), the lower end side is in contact with the fixed rod 29, so that the locking member is centered on the axis W of the guide body 13. A clockwise (arrow-B) rotation action is generated in 17 so that the edge 19a of the through hole 19 comes into strong contact with the peripheral surface of the guide body 13 and is prevented from moving rearward. . On the other hand, when the headrest body 5, that is, the guide body 13 is moved forward (arrow C in FIG. 7), the fixing rod 29 does not work and the through hole 19 is formed in the peripheral surface of the guide body 17.
Since the edges 19a do not strongly contact each other, they can slide.

The switching means 27 is fixed to the operation rod 33 to which the cam body 31 is fixed above the guide body 13, and to the one end side of the operation rod 33 so that the locking member 17 is in the free posture II.
III (FIG. 8) and an operating arm 35 for switching between the second operating position IV in which the locking member 17 is in the locking posture I, and a first stopper P for switching the operating arm 35 between the first and second operating positions III, IV. consists _first and second stopper P ₂ Prefecture, actuating rod 33 across the base bracket 15 is pivotally supported rotatably with each other perpendicular to the guide member 13.

The first and second stoppers P ₁ and P ₂ are fixed to one holding member 7 side, which is the operating arm 35 side, and the operating arm 35 is attached to the first stopper P _{1 when} the headrest body 5 moves to the frontmost position. It is set at a position where they abut each other. Further, the second stopper P ₂ is set at a position where the operating arms 35 come into contact with each other when the headrest main body 5 moves to the rearmost position, and the operating arms 3 are attached to the first and second stoppers P ₁ , P _2.
The first operating position III and the second operating position I are caused by the mutual contact of 5
It is designed to switch to V and.

The operating arm 35 is held in the first operating position III and the second operating position IV by the third biasing spring 37, respectively.

That is, the sub arm 3 protruding from the base of the operating arm 35
5a, one end of the third biasing spring 37 is locked to the base bracket 15 at the other end, and the rotation axis of the operating arm 35 is locked to the third biasing spring 37. The operating arm 35 is biased to the first operating position III and the second operating position IV, respectively, when the sub arm 35 moves to the upper side or the lower side around the dead center around the neutral line X connecting the locking holes of 15. It is like this.

In the headrest adjusting device configured in this way,
When the head of the occupant acts on the headrest body 5, the guide body 1
3 works to move backward, but lock posture I
It is blocked by the locking member 17 at the position to secure the restrained state.

Then, the headrest body 5 can be slid forward to a desired position for adjustment. In this case, since the slide is performed steplessly, the optimum position can be obtained and the operation in the sitting posture can be performed.

On the other hand, in order to move the headrest 3 that is too close to the front toward the rear, the headrest main body 5 is moved to the frontmost position. At this time, the operating arm 35 comes into contact with the first stopper P ₁ to switch from the second operating position IV to the first operating position III, and the locking member 17 becomes the free posture II. At the same time, the headrest body 5 is moved to the rearmost position by the first biasing spring 23.
Will be returned. At this time, the operating arm 35 comes into contact with the second stopper P ₂ and switches from the first operating position III to the second operating position IV, so that the locking member 17 assumes the locking posture I, and therefore the headrest main body 5 is moved forward. If it slides, it will be positioned at the optimum position.

Therefore, even if the operating portion is not exposed to the outside, the slide adjustment can be performed and the feeling of protrusion is eliminated.

[Effects of the Invention] As described above, according to the headrest adjusting device of the present invention, the structure is simple and the headrest body can be adjusted steplessly in the sitting posture, so that the desired position can be reliably set. . Moreover, it is preferable in terms of operability. In addition, since it is possible to eliminate the feeling of protrusion and is not exposed to the outside, it is preferable in terms of appearance quality.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a headrest adjusting device of the present invention, FIG. 2 is a perspective view of a partially cut headrest adjusting device, FIG. 3 is a perspective view of a seatback provided with a headrest, and FIG. FIG. 5 is a partially cutaway side view of FIG. 5, FIG. 5 is a rear view of the same, FIG. 6 is a plan view of the same, and FIGS. 7 and 8 are operation explanatory views of the locking member. DESCRIPTION OF SYMBOLS 1 ... Seat back 3 ... Headrest 5 ... Headrest main body 13 ... Guide body 17 ... Locking member 27 ... Switching means

Claims (1)

[Claims] 1. In a seat having a headrest provided on an upper part of a seatback, a base bracket fixedly supported on the seatback side in the headrest body of the headrest, and a head bracket which is supported by the base bracket so as to be movable back and forth. A fixedly supported guide body, which slidably penetrates the guide body and acts on the peripheral surface of the guide body in a locked posture inclined from the axis of the guide body to allow forward movement and prevent backward movement. On the other hand, in a substantially vertical free posture, a locking member provided with a through hole that allows sliding movement back and forth away from the circumferential surface of the guide body, and a biasing means that biases the locking member to keep the locking posture at all times. , When the headrest main body moves to the frontmost, the locking member in the locked posture is set to the free posture, and when the headrest main body is moved to the rearmost, it is changed from the free posture to the locked posture. Headrest longitudinal adjustment device for an automobile seat, characterized in that it comprises a switch means.