GB2134381A

GB2134381A - Improvements in vehicle seats

Info

Publication number: GB2134381A
Application number: GB08401310A
Authority: GB
Inventors: Alice Dorothy Finnigan
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-02-05
Filing date: 1984-01-18
Publication date: 1984-08-15
Also published as: GB8401310D0

Abstract

A vehicle seat including at least one seat belt (5) to retain a person sitting in the seat, comprises a substantially horizontal seating surface (1) and a backrest comprising a fixed perimeter unit (3) and a movable back support (2), both ends of at least one seat belt (5) being attached to this back support (2), the normal sitting position of the vehicle seat being when the back support (2) is in an upright position, the back support (2) being rotatably mounted by means of a rod (7) such that it may be rotated to a position between its upright position and a position where the back support is in contact with and substantially parallel to the seating surface, the vehicle seat also including a stop rod (4) to prevent the back support (2) from rotating from the upright position in a direction away from the seating surface (1), and biasing means (9, 10) which exert force on the back support (2) to bias it in a direction away from the seating surface, the force applied by the biasing means (9, 10) increasing with the distance that the back support (2) has moved from its upright position. <IMAGE>

Description

SPECIFICATION Improvements in vehicle seats This invention relates to improvements in seats for motor vehicles, especially cars and in particular to vehicle seats which include seat belts to retain the person sitting in the seat.

With the advent of new laws seat belts are now almost universally used, especially by a driver and a passenger in the front seat of a vehicle. Although the seat belts retain a person in the seat when the vehicle jerks or stops suddenly the seat belts can cause great discomfort since the person sitting in the seat is forced against the seat belt which can be very painful.

According to this invention a vehicle seat including at least one seat belt to retain a person sitting in the seat, comprises a substantially horizontal seating surface; a movable back support, both ends of at least one seat belt being attached to this back support, the normal sitting position of the vehicle seat being when the back support is in the upright position, the back support being rotatably mounted with respect to the seating surface such that it may be rotated to a position between its upright position and a position where the back support is in contact with and substantially parallel to the seating surface, the vehicle seat also including a stop to prevent the back support from rotating from the upright position in a direction away from the seating surface, and biasing means which exert force on the back support to bias it in a direction away from the seating surface, the force applied by the biasing means increasing with the distance that the back support has moved from its upright position.

A vehicle seat in accordance with this invention proves much more comfortable for the person sitting in it. When the vehicle jerks or comes to a halt suddenly, the person sitting in the seat is thrust forward, rotating the back support towards the seating surface, the biasing force urging the back support to its upright position. The person sitting in the seat is not jerked back towards the upright sitting position since the biasing force decreases as the back support returns to its upright position. Thus the passenger is still retained in the seat by the seat belts but the movement of the back support serves to absorb some of the force which would have been applied to the person by the seat belt preventing this painful pressure.

Preferably the movable back support extends upwardly to form a neck support so that the movement back to the upright position does not jolt the neck of any person sitting in the seat.

The back support may be mounted on the seating surface by means of a rod which is attached to the back support which is slotted into sockets on the fixed vehicle seat. The rod is rotatably mounted in these sockets.

The biasing means may be in the form of a torque spring which is attached to the rod, the torque applied by the spring increasing as the back support moves from its upright position.

Preferably, however the rod which rotates with the back support has at least one washer attached to it, the washer being cut away so that it appears semi-circular. Beneath the rod and sockets which serve to mount the back support is situated a short strong spring. When the back support rotates away from its upright position the cut away edge of the washer comes into contact with this spring which urges the back support to its upright position.

However, it does not serve to increase inertia on the backward moving person since as soon as the back support is near its upright position the cut away end of the washer is not in contact with the spring.

It is preferred that the biasing force is provided by at least two of these washers and springs.

A preferred form for the stop which prevents the back support from rotating from its upright position in a direction away from the seating surface is a horizontal metal bar at shoulder level which is connected to a fixed perimeter unit which surrounds the edges of the movable back support.

Preferably the vehicle seat includes two seat belts one at each side of the seat, each seat belt being attached to the movable back support at a point just above shoulder level and a point just under the arm.

Enough slack is allowed for a person sitting in the vehicle seat to slot their arms through the seat belts.

It is preferred that the vehicle seat also includes an auxiliary seat belt which is attached to the horizontal seating surface and is strapped over the thighs.

The seats may have weighted straps attached to them which are slung overthe backofthe metal bar acting as a stop. This serves as a backward pull on the forward impetus of the back support when it is moving towards the seating surface in the event of a jerk or a sudden stop.

Preferably however the seats include straps attached to the movable back support just above the shoulders which are spring biased and bias the movable back support to an upright position. These straps may conveniently take the form of auxiliary seat belts.

Three examples of car seats in accordance with the present invention will now be described with reference to the accompanying drawings, in which Figure 1 is an exploded front view of the back support means of the first example of a car seat; Figure 2 is a schematic view showing the cut away washer in contact with the spring; Figure 3 is a shematic section of a second example of a car seat; Figure 4 is a schematic rear view of a third example of a car seat; and, Figure 5 is a schematic section through Figure 4.

A vehicle seat comprises a seating surface 1 and a movable back support 2. Around the back support 2 is a fixed perimeter unit 3 on which is mounted a metal rod 4 which serves as a stop to prevent the back support 2 from rotating from its upright position away from the seating surface 1. The movable back support 2 has attached to it two seat belts 5 which are attached just above shoulder level and just below the arm. The back support 2 also carries weighted straps 6 which serve to have a backward pull on the forward inertia of the seat. The back support 2 is mounted on the perimeter unit 3 by means of a metal rod 7 which is slotted through sockets 8 on the perimeter unit 3. Mounted on the rod 7 are two washers 9 which are cut away to form a semi-circle.When the back support 2 rotates forwards in the event of a jerk or sudden stop the washers 9 rotate forwards and come into contact with springs 10 which urge the back support 2 away from the seating surface 1 and towards its upright position.

A second example of a car seat is shown in Figure 3. In this case an auxiliary biasing force is applied by spring bias straps 11. Straps 11 are included on both sides of the seat but only one strap will now be described, the other strap being identical to this one.

The strap 11 is connected to the movable back support 2 and is thread around the rod 4 which acts as a stop and is connected to the rigid perimeter unit 3.

The strap 11 is threaded around three more rods 12, 13 and 14which are also attached to the rigid perimeter unit 13. The rods 4, 12, 13 and 14 may be fixed or rotatably mounted on the rigid perimeter unit 13 and serve to tension the strap 11. The rods 4, 12, 13 and 14 are not colinear and thus the perimeter unit 3 needs to be constructed of such a depth to allow the rods to be spaced to tension the strap 11.

The strap 11 is then slotted through a slit 15 in the metal plate 16 to which the spring 10 is attached, the strap 11 is then wound around the edge of the plate 16. The end of the strap 11 is then welded to the rest of the strap 11 to form a loop 17. A spring 18 is welded to the inside of loop 17.

When the movable back support 2 jerks forward the strap 11 is pulled forward and the spring 18 bears against the metal plate 16 and pulls the strap 11 backwards, thus exerting an extra biasing force on the movable back support 2.

Athird example of a car seat includes a seat belt 18 attached to the movable back support 19 at chest level.

Two auxiliary seat belts 20 are situated at each side of the back support 19. The seat belts are identical but only ine will be described.

One end of the seat belt 20 includes a loop 21 which encloses a spring 22 attached to a fixed plate 23 which is similar to the spring attachment of strap 11 of the second example. The seat belt 20 extends upwardly to just above shoulder height where it passes through a slit 24 in back support 19. The two seat belts 20 cross-over but are connected together by strap 25.

The back support 19 has rearwardly extending wings 26 at its vertical edges. A metal plate 27 extends between the wings 26. The plate includes two pairs of slots 28 and 29. Between the slots (28, 29) of each pair is attached a spring 30 on the rear surface of plate 27. The seat belt 20 is threaded through slot 28, passes over spring 30 and through slot 29 and is attached to the rest of the belt 20 at 31.

This third example of seat does include the features of the first example of the car seat except for the weighted straps 6. The spring-biased belts 20 serve as an extra backwards pull on the forward impetus of the back support 19, on impact.

Claims

1. A vehicle seat including at least one seat belt to retain a person sitting in the seat, comprising a substantially horizontal seating surface, a movable back support, both ends of at least one seat belt being attached to this back support, the normal sitting position of the vehicle seat being when the back support is in an upright position, the back support being rotatably mounted with respect to the seating surface such that it may be rotated to a position between its upright position and a position where the back support is in contact with and substantially parallel to the seating surface, the vehicle seat also including a stop to prevent the back support from rotating the upright position in a direction away from the seating surface, and biasing means which exert force on the back support to bias it in a direction away from the seating surface, the force applied by the biasing means increasing with the distance that the back support has moved from its upright position.

2. A vehicle seat according to claim 1, in which the movable back support extends upwardly to form a neck support.

3. A vehicle seat in accordance with claim 1 or 2 in which the back support is mounted on the seating surface by means of a rod attached to the back support, and slotted into socketd on the fixed vehicle seat, the rod being rotatably mounted in these sockets.

4. A vehicle seat in accordance with claim 3, in which the biasing means comprise a torque spring attached to the rod, the torque applied by the spring increasing as the back support moves from its upright position.

5. A vehicle seat in accordance with claim 3, in which the biasing means comprises at least one washer attached to the rotatable rod the washer being cut away so that it appears semi-circular, and a spring beneath the rod and sockets, such that when the back support rotates away from its upright position the cut-away edge of the washer comes into contact with this spring to urge the back support towards its upright position.

6. A vehicle in accordance with claim 5, in which the biasing means comprises at least two washers and springs.

7. A vehicle seat in accordance with any one of the preceding claims in which the stop prevents the back support from rotating from its upright position in a direction away from the heating surface is a horizontal metal bar at shoulder level connected to a fixed perimeter unit which surrounds the edges of the movable back support.

8. A vehicle seat in accordance with claim 7, also including weighted straps attached to the movable back support which are slung over the back of the metal bar acting as a stop.

9. A vehicle in accordance with claim 7, in which the seats include straps attached to the movable back support just above the shoulders which are spring biased and bias the movable back support to an upright position.

10. A vehicle seat in accordance with any one of the claims 1 to 7, in which two auxiliary spring biased seat belts are situated at each side of the seat, such that extra movement is allowed on impact.

11. A vehicle seat in accordance with any one of the preceding claims including two seat belts, one at each side of the seat, each seat belt being attached to the movable back support at a point just above shoulder level and a point just underthe arm.

12. A vehicle seat in accordance with any one of the preceding claims, which also includes an auxiliary seat belt attached to the horizontal seating surface to be strapped over the thighs.

13. A vehicle seat in accordance with claim 1, and arranged substantially as described herein.

14. A vehicle seat arranged substantially as herein described with reference to Figure 1, Figure 3 or Figure 4 and 5 of the accompanying drawings.