Inflatable head restraint

An inflatable head restraint device for vehicle is disclosed. An inflatable head restraint device comprising an inflatable air bag, an inflation device, a sensing device, characterized in that the inflatable air bag can be deployed to be a U-shaped cushion for restraining the head and neck and back portion of an occupant, preventing whiplash injury from either rear, front or side impact crash.

BACKGROUND OF THE INVENTION

(a) Technical Field of the Invention

The present invention relates to an inflatable head restraint device for a vehicle seat, and in particular, a device for restraining the head and neck and backbone portion of an occupant, preventing injury to the head and neck from either rear, front or side impacted crash.

(b) Description of the Prior Art

The head restraint device developed by SAAB makes use of a linking rod connected to a trigger board on the seat back. When a rear impact happens to the car, the trigger board will be pushed backward by the jolt of occupant's body which moves the headrest downward to hold the head portion of a passenger to minimize injuries. The WHIPS device developed by Volvo makes use of pendulum-like backward and downward moment of the headrest and the seat back, and in particular the headrest will be moved backward to hold the head of the passenger so as to minimize the impact force exerted to the neck portion. The backward movement of the seat back and the headrest is in two stages. First, the parallel backward movement of the sea back and the headrest, and then the seat back will be slightly tilted at the second stage. However, the head restraint of those conventional designs provides only the buffering protection to the head for rear impact. There is still lack of protection for head and neck from all aspects to the front, rear or lateral impact. Accordingly, it is an object of the present invention to provide a head restraint device for a vehicle seat, which mitigates the above drawbacks.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide an inflatable head restraint device for a vehicle seat, wherein an inflatable air bag is deployed from the headrest and seat back serving as a buffering effect to restrain the head, neck and backbone portion of a passenger preventinginjury from either a front or rear impact.

A second object of the present invention is to provide an inflatable head restraint device for a vehicle seat, wherein the side wing of the inflatable air bag is deployed to restrain he head and neck of the passenger preventing injury from the sudden jolt when a lateral impact happens.

A third object of the present invention is to provide an inflatable head restraint device for a vehicle seat, wherein the extended tag bag portion of the inflatable air bag is deployed offering a better support for the back and the neck portion from injury.

A fourth object of the present invention is to provide an inflatable head restraint device wherein the inflatable air bag is folded and repacked in order for re-use.

A fifth object of the present invention is to provide an inflatable head restraint device wherein the deployment of the inflatable bag can be initiated by a sudden pull of the seat belt, caused by an abrupt forward thrust of the occupant's body.

The foregoing object and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Identical reference numerals are used throughout the specification and drawings to refer the identical or similar parts.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

For the purpose of enhancing an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings. Specific terms will be used to describe the same. It will, nevertheless, be understood that no limitation of the scope of the invention is thereby intended, alterations and further modifications in the illustrated device, and further applications of the principles of the invention as illustrated herein being contemplated as would normally occur to one skilled in the art to which the invention relates.

The term “inflatable head restraint” is defined as an inflatable device that is mounted at the headrest and the back of a vehicle seat is set to be able to be inflated as a cushion to restraint the head and neck portion of a passenger when an impact happens. The device may comprise of a cushion device (e.g. inflatable air bag), an inflation device (e.g. pressurized gas cylinder) and a sensing device.FIGS. 1 and 2show a preferred embodiment of an inflatable air bag, mounted onto the headrest12and the back11of seat10. The inflatable air bag comprises a head bag121, a pair of side bags122and an extended tag bag111. The head bag121and a pair of side bags122is folded and mounted into the headrest12to form a U-shape head portion. The extended tag bag111is a downward extension from the head bag121and mounted onto the upper center part of the seat back near the headrest12, allowing the backbone of occupant to be closely leaned against thereto. All these air bags121,122and111are folded in a pattern that can be easily reassembled and packed inside the headrest12for re-use, as shown onFIGS. 2 and 6. Resealable fasteners are used as the seams1211,1221and1111to seal said packed airbags121,122and111to allow for repeated use. Said air bags121,122and111are connected to a pressurized gas cylinder20by inflation tubes213,223and233, Said pressurized gas cylinder20can be disposed inside the headrest12or the seat back11, as shown onFIGS. 3 and 3A. A controllable valve21is provided at the nozzle the pressurized gas cylinder20to control the release of the air. A seat belt pulling force sensing box30, housing the seat belt40, is mounted at the shoulder of the seat back11. Once a sudden and strong pulling force of the seat belt exceeds a certain preset threshold, the sensing box30will initiate the opening of the valve21promptly to release the air. Alternatively, the sensing device as the conventional air bag equipped can be connected to the valve21, so at the controllable valve21of the inflatable head restraint device can be ignited as the conventional air bag system does.

FIG. 4Ashows the sensing box30comprises a double ends torsion spring31with an axis gear32setting through the center of its axis. Said seat belt40slides through the channel33between the inner wall of the sensing box30and the torsion spring31, and winds around the axis gear32. The elasticity of the torsion spring31was set to allow the sliding of the seat belt40within normal pulling force. A trigger gear34bound by a linking cable35is set in front, but at a distance from the said axis gear32. As shown onFIGS. 5A and 5B, said linking cable35connects to the trigger211of the control valve21of pressurized gas cylinder20through the center of the coil of a tension spring212. Said tension spring212is fixed to an anchor plate2130and pushes said trigger211of the control valve21to keep the pressurized gas cylinder20in a close status at normal condition.

Referring toFIGS. 4A and 4B, when an impact happens to the car, the seat belt40would sustain a sudden force due to the abrupt forward thrust of the occupant's body. Once force is greater than the preset threshold of the said torsion spring31, the seat belt40that is wound around the said torsion spring31would be pulled straight and push the axis gear32in contact with the trigger gear34. When the was gear32and the trigger gear34are in contact, the pulling of the seat belt40will drive the trigger gear34to wind the linking cable35, consequently, pulling the trigger211of the control valve21to open and release the air from the pressurize gas cylinder20. Thus the air will be promptly released from the pressurized gas cylinder20to deploy the air bags111,121and122through the inflation tubes213,223and233. In accordance with the present invention, alternative sensing initiation mechanism can be used such as: electric switch50as shown inFIGS. 6A,6B and6C or the conventional sensing system for airbag. Once the pulling force is greater than the preset elastic threshold of the said torsion spring31, trigger rod51of the axis gear32will be pushed to press the electric switch50and initiate an electric signal to the electrical controllable release valve52through a cable53to open and release the air from the pressurized gas cylinder20. Referring toFIGS. 7,8A,8B and8C, when an impact happens to the car, the seat belt40will be pulled forward due to the inertia force of the passenger, once the pulling force of the seat belt is stronger than the preset elastic threshold of the torsion spring31, the axis gear32is pressed to be in contact with the trigger gear34, thus drives the trigger gear34and winds the linking cable35. Consequently, the pulling of the seat belt will initiate the opening of the controllable valve21to release the air from the pressurized gas cylinder20and deploy the air bags111,121and122trough the inflation tubes213,223. The head bag121and the pair of side bags122form a U-shaped cushion serving as a buffering effect to protect the head and neck portion of a passenger from y induced by either a front or rear impact; said pair of side bags122is designed to further protect the head and neck of the passenger from injury by the lateral thrust when a side impact happens; the extended tag bag111will offer a better support for the backbone and the neck portion from injury. All these air bags121,122and111are characterized in folding in a pattern that can be easily folded back and repacked inside the headrest12for re-use.

It will be appreciated by person skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and sub combinations of the features described hereinabove as well as modifications and variations thereof which would occur to a person skill in the art upon reading the foregoing description and which are not in the prior art.