GB2407969A

GB2407969A - Seat for aircraft or helicopter having hydraulic damping

Info

Publication number: GB2407969A
Application number: GB0326406A
Authority: GB
Inventors: Stephen William Gray
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-11-12
Filing date: 2003-11-12
Publication date: 2005-05-18
Anticipated expiration: 2023-11-12
Also published as: GB2407969B; GB0326406D0

Abstract

A vehicle seat (2) is provided that may be used in a Helicopter. The seat is pivotally mounted to the floor of the vehicle and may rotate / recline in a rearwards direction in the event of a crash. The seat incorporates a least one resistive damping device (1), to slow the motion of the seat and the occupant therein, and hence may absorb shock loadings in the event of a crash. The damping device(s) may take the form of hydraulic cylinder(s) that retard motion. As the rear of the seat rotates toward the floor the front of the seat moves about a second point (3).

Description

1 2407969 Safety Seat

General Description

The aim of the seat would be to protect an occupant from lethal vertical compressive forces as may be experienced in a crash. The principle intended use would be as a helicopter seat although other used could be envisaged.

The problem with helicopter crashes in particular is that the main force is vertical and most traditional seats are either rigid or compress only in a vertical plain.

In a crash, this seat is designed to rotate after a release point has been reached and spread the forces over much of the body rather than concentrating them on the base of the spine.

The rotation also provides extra time and space to retard vital organs of the human body such a head and upper body and improves the survivability of such a crash.

The seat would have three main component areas: The rear support which could house a dampening system. (a) The seat bucket incorporating a head restraint. (2) The front support. (3) The Rear Support (1) A hydraulic arrangement is shown for demonstration purposes only.

This support can comprise of several components and sub-components.

The attachment position chosen at the design stage could be between the lumber and shoulder areas. This choice would allow a resultant overhang to be predominantly at the front, the rear or shared between the front and rear of the seat location.

Depending upon the chosen attachment location, the supported load would vary disproportionately to the forces acting upon it and for this reason, a compensating arrangement may be required.

It would be desirable to have the resistive force of the seat increase during activation to take advantage of the improved posture of the occupant and to widen its operational parameters. In the event that a high attachment position is chosen, this may be 'automatic' as more weight is placed upon the front support. Where a lower attachment is chosen, a compensating device could be employed.

Once activated, a retardation system would need to prevent the seat from returning to its normal position. It was anticipated that hydraulic liquid loss would serve this purpose and act to assist with fire risk by forming an inert mist.

The Seat Bucket. (2) The seat bucket is a ridged structure attached to rear support at either side and at the front support at the knee area. Space under the seat could be utilised e.g. to store a life jacket, provided that it is attached to the seat bucket and not the floor.

The Front Support (3) This support can comprise of several components and sub-components.

The front support is intended to be either a slide or pivot arm attached to the Seat Bucket and it's purpose is to allow the seat to travel both forwards and upwards but not to collapse when activated.

A rigid support with a pivot could be utilised if the design of the Rear Support could accommodate this.

Materials

Any material which meets the design specification.

Operation When the load on the seat exceeds the design loading, the back part of the seat will descend. The point of release will be set to restrict the load on the spine to acceptable levels. Hydraulic dampers with preset or adjustable release valves were envisaged and the resultant liquid loss could serve as a fire suppressant.

As the front support is incompressible, the seat bucket will additionally incline (rotate) during it's travel. This will lessen the load on the spine and as a consequence, allow greater forces to be experienced prior to serious injury.

The unique feature is the inclining (rotating) nature of the seat bucket and although other parts are required to control the operation, the variety of solutions to achieve this are such it would be best to design these once a location has been selected.

Claims

1. A safety seat that incorporates pivots and resistive devices to allow it to incline (rotate) so as to permit an improved posture.

2. The additional downward movement available from claim 1, which allows the upper body a slower rate of retardation.

3. A safety seat as claimed in any preceding claim where there is a much improved chance of survival in the event of a crash and includes vertical rotation.

4. A safety seat substantially as herein described above and illustrated in the accompanying drawings

4. A safety seat substantially as herein described above and illustrated in the accompanying drawings Amendments to the claims have been filed as follows: 1. A safety seat that incorporates pivots and resistive devices to allow it to incline around an axis of rotation that passes between the left- hand side and the right-hand side of the seat when subjected to harmful vertical forces so as to permit an improved posture of the occupant.

2. The additional movement available from claim 1, which allows the upper body a slower relative rate of retardation when subjected to vertical forces by utilising the space between the head of an occupant and the cabin floor.

3. A safety seat as claimed in any preceding claim where there is a much improved chance of survival in the event of a crash and includes rotation as set out in Claim 1 and vertical movement as set out in claim 2.