JPH0767744A - Automatically movable head rest for vehicle - Google Patents

Abstract

PURPOSE: To reduce a whiplash and a motion sickness by processing output signals of a head part position detecting device and a impact intensity detecting device arranged in a headrest by a control device, outputting them to an automatically movable headrest, and reducing backward acceleration acting on a head part of an occupant. CONSTITUTION: This automatically movable headrest 7 fixed to a seat 8 by a fixing rod 6 is composed of a protective plate 1, a cylinder 2 and a headrest fixing part 3, and encloses a head part position detecting device 4 and an impact intensity detecting device 5. When a head part longitudinally moves by a collision, suddent acceleration/deceleration and irregular acceleration/deceleration, the head part position detecting device 4 detects and outputs a position of the head part, and the impact intensity detecting device 5 detects and outputs impact intensity from extension/contraction of the cylinder 2. A signal processing and output control device sends a cylinder control signal such as pneumatic pressure and oil pressure to the automatically movable headrest 7 through an automatically movable headrest control device, and relieves backward acceleration imparted to the head part. Therefore, a whiplash and a motion sickness of an occupant can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle seat headrest.

[0002]

2. Description of the Related Art A conventional headrest is fixed to a vehicle seat, and is considered and manufactured to support a head.

[0003]

At the time of a vehicle collision or a sudden deceleration of the vehicle, the trunk and head of the occupant are in a posture of leaning forward around the waist, and at the same time when the vehicle stops or accelerates, A backward acceleration is applied to the head, and the head suddenly moves backward. As a result, the head is hit hard against the headrest. The impact that the head and neck receive from the headrest when moving backward increases as the backward acceleration increases. When this impact is large, the neck is damaged, which causes an obstacle such as whiplash.

Further, the discomfort such as motion sickness caused by the forward and backward movement of the head caused by the irregular acceleration and deceleration of the vehicle is because the neck is more flexible than the trunk and the waist.
It is caused by the fact that the head constantly responds to the progress of the vehicle and repeats forward and backward movements.

The trunk can be fixed by a seat belt. However, when a vehicle collides, when the vehicle is rapidly decelerated or when the vehicle is irregularly accelerated or decelerated, there is no method for supporting the head, and the head moves freely back and forth depending on the progress of the vehicle.

The present invention was made by paying attention to the above-mentioned two problems caused by the lack of a method for supporting the head. The purpose is to reduce the rearward acceleration acting on the head and to reduce the impact on the head and neck immediately after the vehicle collision and the rapid deceleration of the vehicle. Similarly, it is to alleviate discomfort such as motion sickness caused by the forward and backward movement of the head caused by irregular acceleration and deceleration of the vehicle.

[0007]

In order to achieve the above object, the present invention provides a headrest with a head position detecting device and a head impact strength detecting device, processes signals from the respective detecting devices, and processes the signals. The headrest is configured to move according to the movement of the head by the mechanism driven by the generated signal.

[0008]

When the head moves forward from the headrest during a collision of the vehicle and during a rapid deceleration of the vehicle, the headrest rapidly moves to a position that supports the head in accordance with the movement of the head. When the trunk or the head of the occupant starts moving backward due to the stop or acceleration of the vehicle, the headrest gradually moves to the original position while keeping the head supported.
In this way, by acting on the free forward and backward movement of the head and controlling the backward acceleration acting on the head, the impact on the head and neck is reduced. Similarly, discomfort such as motion sickness due to irregular acceleration and deceleration of the vehicle is reduced. Further, in the rearward movement of the headrest, the degree of impact relaxation and the degree of discomfort reduction are increased by changing the moving speed according to the impact strength received by the headrest.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 shows the system configuration of an automatic movable headrest for a vehicle. This system consists of three units: an automatic movable headrest, a signal processing and output control device, and an automatic movable headrest control device.

First, each unit will be described. As shown in FIGS. 2 to 5, the automatically movable headrest is divided into a movable portion and a fixed portion. The movable part and the fixed part are connected by a cylinder. This cylinder expands and contracts in multiple stages, and the drive source is hydraulic, pneumatic or electric.

The movable portion of the headrest incorporates a protection plate molded from a shock-resistant synthetic resin material in a cushion material, and is connected to the cylinder by the protection plate. A head position detecting device using a photoelectric sensor is provided at the tip of the protective plate, and an impact strength detecting device that detects the impact strength as a change in electrical resistance with a strain gauge is provided at the center.

The headrest fixing portion is composed of a metal plate for fixing the cylinder and a metal rod for fixing to the vehicle seat, which is integrated with the plate, and is covered with a cushion material except for the fixing rod for the seat. It is a structural object.

The signal processing and output control device processes a head position signal provided in the headrest movable part, and outputs it to the automatic movable headrest control device as a switching signal between the forward movement and the backward movement of the headrest movable part. At the same time, the impact strength signal is processed and output to the automatic movable headrest control device as a speed control signal for backward movement.

The automatic movable headrest control device switches and outputs the cylinder drive source in response to a switching signal from the signal processing and output control device, and determines the operating direction of the headrest movable portion. At the same time, in the case of reverse operation, the speed control signal controls the amount of supply from the drive source to the cylinder to change the reverse speed.

Next, the overall operation of the vehicle automatic movable headrest will be described. When the occupant's head moves forward from the headrest due to a vehicle collision, sudden deceleration, or irregular acceleration / deceleration, the photoelectric sensor operates and the signal processing and output control device switches to the automatic movable headrest control device. Is output. The automatic movable headrest control device switches the cylinder drive source to the forward direction and outputs it to the cylinder. Therefore, the cylinder extends and the movable portion of the headrest starts the forward movement and rapidly moves to the position of supporting the head.

When the headrest movable portion supports the occupant's head, the photoelectric sensor is shielded by the head and becomes inoperative, and the signal processing and output control device outputs a switching signal to the automatic movable headrest control device. The automatic movable headrest control device switches the cylinder drive source to the reverse direction and outputs it to the cylinder. Therefore, the forward movement of the headrest movable part stops, and the reduction of the cylinder causes
The movable portion of the headrest starts the backward movement and gradually moves to the original position with the head supported.

The speed control in the backward movement of the movable portion of the headrest will be described. When the backward acceleration of the head is large, the impact received by the headrest movable part is large, and the output signal of the impact strength detection device provided in the headrest movable part is large in proportion to the impact strength. The impact strength signal is processed by the signal processing and output control device and output to the automatic movable headrest control device as an automatic movable headrest speed control signal. The automatic movable headrest control device controls the supply amount from the drive source to the cylinder by the speed control signal. That is, the headrest moving part supports the head while moving at a variable speed by increasing or decreasing the supply amount from the drive source to the cylinder and controlling the contraction speed of the cylinder according to the backward acceleration of the head. It will be a thing.

[0018]

Since the present invention is constructed as described above, it has the following effects.

During a vehicle collision or sudden deceleration, the impact of the head and neck received by the abrupt back and forth movement of the head and trunk is mitigated, damage to the neck is minimized, and whiplash and other obstacles are caused. Reduce.

It is possible to reduce uncomfortable feeling such as motion sickness caused by the forward and backward movement of the head caused by the irregular acceleration and deceleration of the vehicle.

[Brief description of drawings]

FIG. 1 is a system diagram of an automatic movable headrest for a vehicle.

FIG. 2 is a plan view of an automatically movable headrest.

FIG. 3 is a plan view of the automatic movable headrest during operation.

FIG. 4 is a side view of an automatically movable headrest.

FIG. 5 is a side view of the automatic movable headrest during operation.

FIG. 6 is a side view of an automatically movable headrest mounted on a vehicle seat and an occupant.

FIG. 7 is a side view of an automatically movable headrest and an occupant mounted on a vehicle seat during operation.

[Explanation of symbols]

 1 Protective plate 2 Cylinder 3 Headrest fixing part 4 Head position detecting device 5 Impact strength detecting device 6 Seat fixing rod of automatic movable headrest 7 Automatic movable headrest 8 Seat 9 Seatbelt

Claims (1)

[Claims] 1. A device for detecting the movement of the occupant's head and a device for detecting the strength of the impact acting on the occupant's head are provided, and the device for automatically supporting the occupant's head in accordance with the forward / backward movement of the occupant's head A headrest device, which is characterized by performing forward and backward movements.