JPS6318488B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a headrest that can be adjusted in the longitudinal direction.

Various types of headrests of this kind have been proposed in the past, but all of them have the disadvantage of complex structures and inability to adjust the position easily, quickly, and reliably in the longitudinal direction.

An object of the present invention is to provide a front-rear position adjustable headrest that can be adjusted simply, quickly, and reliably in the front-rear direction, and that can be constructed simply with fewer parts. It will become clear.

1 to 3 show an embodiment of the present invention, in which a fixed plate 2, a movable plate 5, a hollow housing 8, a rotary shaft 10, and a movable plate forming a mechanism for converting linear motion into rotational motion are shown. Rack 11a, 11b provided on plate 5, pinions 12a, 12b provided on rotating shaft 10, rotating shaft 10
The headrest body 15 is provided with a coil spring 13 for locking the headrest, an operating lever 14 thereof, and a headrest body 15 attached to the movable plate 5.

Channel-type guide rails 3a, 3b are formed at both ends of the fixed plate 2 in the width direction, and a guide hole 4 for an operating lever is provided in the middle part. The fixing plate 2 is fixed between the upper ends of the stays 1a and 1b which are inserted into a seat back frame (not shown).

The movable plate 5 has a middle portion formed into a mold, and guide portions 6 at both ends thereof that fit into guide rails 3a and 3b formed on the fixed plate 2.
a, 6b are provided, and racks 11a, 11b are formed on both sides of the intermediate portion. The movable plate 5 is disposed on the fixed plate 2 and is assembled so as to be able to move in parallel in the front-rear direction via guide portions 6a and 6b fitted to the guide rails 3a and 3b. In addition, the first
In the figure, the front and back direction of the movable plate 5 is indicated by an arrow f.

Tension springs 7a and 7b are attached to both sides of the intermediate portion between the fixed plate 2 and the movable plate 5, and the movable plate 5 is always urged forward by the tension springs 7a and 7b. There is.

The housing 8 is formed into a hollow shape capable of accommodating the rotating shaft 10 and the coil spring 13, and holes for hooking the ends of the coil spring 13 are provided at both ends in the axial direction, and an operation hole is provided at the bottom side. A guide hole 9 for a lever is provided. Further, the housing 8 is disposed at a central portion on the fixed plate 2 and is fixed to be elongated in the axial direction.

The rotating shaft 10 is inserted into the housing 8, and both ends thereof are placed on guide rails 3a and 3b formed on the fixed plate 2.
Pinions 12a and 12b are provided on both sides of the intermediate portion of the rotating shaft 10, that is, between the housing 8 and the guide rails 3a and 3b.

Rack 11 provided on the movable plate 5
a, 11b and the pinion 1 provided on the rotating shaft 10
2a and 12b are intermeshed with each other, and the rotating shaft 1
These rack and pinion 11
The movable plate 5 can be moved in the front and back direction through the operation of the actuators a, 11b, 12a, and 12b.

In this embodiment, the coil spring 13 is wound around the outer circumferential surface of the rotating shaft 10, and both ends 13
a and 13b are latched into latching holes provided at both ends of the housing 8, and are contracted in the diametrical direction to press against the outer peripheral surface of the rotating shaft 10.
It is configured to be able to lock 0. Also,
The winding direction of the coil spring 13 is such that when a load is applied to the movable plate 5 in the direction of pushing it from the rear to the front, it acts to release the lock of the rotating shaft 10, and on the contrary, it works to push the movable plate 5 from the front to the rear. When a load in the forward direction is applied, the locking force on the rotating shaft 10 is strengthened.

The operating lever 14 is a coil spring 13
Guide holes 9 and 4 are provided in the middle part of the housing 8 and the fixed plate 2 in the longitudinal direction.
By operating the operating lever 14 in the direction opposite to the winding direction of the coil spring 13, that is, in the direction of arrow g shown in FIGS. 1 and 3, the coil spring 13 can be operated from the outside. The diameter is enlarged and the rotation shaft 10 is unlocked.

The headrest main body 15 has screws 18 inserted into mounting holes 16 provided in the headrest main body 15 itself.
A screw hole 1 passed through the movable plate 5 and provided in the movable plate 5
7, it is attached to the movable plate 5.

The front and rear position adjustable headrest of the above embodiment is as follows:
It is operated and works as follows.

In a normal state, the rotating shaft 10 is locked from rotating due to the contraction action of the coil spring 13 in the diametrical direction, and the pinions 12a, 12b provided on the rotating shaft 10 and the racks 13a, 13b provided on the movable plate 5 are locked. The movable plate 5 with the headrest body 15 is therefore fixed in position.

In this state of use, when a load is applied in a direction that pushes the headrest main body 15 backward due to pressure on the user's head, the movable plate 5,
Rack and pinion 11a, 11b, 12a, 12
b and the coil spring 1 through the rotating shaft 10.
3 acts, the locking force of the coil spring 13 on the rotating shaft 10 is strengthened,
The movable plate 5 and the headrest body 15 are further stabilized.

In addition, when a load is applied to the movable plate 5 and the headrest main body 15 in a direction that pushes them forward, such as when the vehicle is suddenly braked, when the movable plate 5 and the headrest main body 15 are used as a headrest for a car seat, for example, the movable plate 5. Rack and pinion 11a, 11b, 12a, 12b and rotating shaft 1
Since the load is absorbed by the coil spring 13, each member from the movable plate 5 to the coil spring 13 functions as a shock absorber.

Next, when adjusting the longitudinal position of the headrest main body 15, move the operating lever 14 as shown in FIG.
As shown by arrow g in FIG. 3, by operating the coil spring 13 in the opposite direction to the winding direction, the diameter of the coil spring 13 is expanded and the rotation shaft 10 is unlocked. As a result, the action of the tension springs 7a and 7b provided between the fixed plate 2 and the movable plate 5 and the rack and pinion 1
1a, 11b, 12a, and 12b, the movable plate 5 is operated forward, and when the operating lever 14 is released at an arbitrary position, the coil spring 13 contracts in the diametrical direction again, and the rotating shaft 10 is locked, so that the headrest The main body 15 can be easily and quickly adjusted to any position.

When adjusting the headrest main body 15 to the rear of the preset position, use the operating lever 14 to adjust the coil spring 1 as described above.
After releasing the lock on the rotating shaft 10 of 3, push the headrest 15 or the movable plate 5 backward against the spring force of the tension springs 7a and 7b,
Then, when the operating lever 14 is released at an arbitrary position, the coil spring 13 contracts in the diametrical direction, and the rotation shaft 1
Since 0 is locked, adjustment to any desired position can be made easily and quickly in this case as well.

The above is the configuration of one embodiment of the front-rear position adjustable headrest according to the present invention. According to this configuration, a fixed plate, a movable plate having a headrest body and movable in the front-back direction with respect to the fixed plate, A rotating shaft fitted into a fixed housing, a mechanism provided between the movable plate and the rotating shaft for converting linear motion into rotary motion, a coil spring that presses against and locks the circumferential surface of the rotating shaft, and the coil spring. By applying force in the opposite direction to the winding direction and releasing the lock on the rotating shaft, the headrest body can be moved almost steplessly in the front and back direction.
In addition, the position can be adjusted easily and quickly, and the position can be fixed at the adjusted position.

Further, according to the present invention, fewer parts are required compared to the conventional one, and the shape of each part can be simplified, so that the overall structure can be simplified.

The above description merely shows one embodiment of the present invention, and without departing from the spirit of the present invention,
It will be obvious that various modifications and changes may be made.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention;
FIG. 2 is a longitudinal sectional front view of the assembled state, and FIG. 3 is a perspective view of a coil spring for locking the rotating shaft and an operating lever provided thereon. In the figure, 1a, 1b...stay, 2...fixed plate, 5...movable plate, 8...housing,
10... Rotating shaft, 11a, 11b, 12a, 12
b... Rack and pinion which is a mechanism for converting linear motion into rotational motion, 13... Coil spring for locking the rotating shaft, 14... Coil spring operating lever, 15... Headrest body, f... Movable plate Forward direction, g...Direction of force applied to the operating lever to unlock the rotating shaft.

Claims (1)

[Scope of Claims] 1. A device comprising a fixed plate and a movable plate that can move in the front and back direction, a hollow housing is fixed to the fixed plate, a rotating shaft is fitted into the housing, and the rotating shaft has a diameter. A coil spring is wound around the rotary shaft, which can contract in the direction to press against the outer circumferential surface of the rotating shaft, or expand in the diametrical direction to press against the inner circumferential surface of the rotating shaft, and can lock the rotating shaft. It is rolled up symmetrically, its both ends are hooked to both ends of the housing, and its center part is formed to protrude downward in a U-shape to form an operating lever, and the operating lever is connected to the housing and the fixed plate. The coil springs are projected to the outside through guide holes respectively formed in the headrest body, and the coil springs lock the rotating shaft when a load is applied to the movable plate to which the headrest body is attached in the direction of pushing it forward from the rear. On the other hand, when a load is applied in the direction of pushing from the front to the rear, the locking force against the rotating shaft is strengthened. A front-rear position adjustment type, characterized in that a mechanism for converting linear motion into rotational motion is provided, and the movable plate is configured to be movable in the front-rear direction through activation of the mechanism for converting the linear motion into rotational motion when the rotating shaft is unlocked. Headrest. 2. The mechanism for converting linear motion into rotational motion is comprised of pinions formed on the outer periphery of both sides of the rotating shaft protruding from the housing, and racks formed on both sides of the movable plate. A front-rear position adjustable headrest according to claim 1.