GB1574275A

GB1574275A - Safety apparatus for restraining a seated occupant in a vehicle

Info

Publication number: GB1574275A
Application number: GB16510/78A
Authority: GB
Original assignee: BSG International Ltd
Current assignee: BSG International Ltd
Priority date: 1977-12-17
Filing date: 1978-04-26
Publication date: 1980-09-03
Also published as: FR2411734B2; IT7850928A0; DE2756401C2; JPS5486127A; IT1202835B; JPS6114973B2; FR2411734A2; DE2756401B1

Description

(54) SAFETY APPARATUS FOR RESTRAINING A SEATED OCCUPANT IN A VEHICLE (71) We, B.S.G.INTERNATIONAL LIMITED, a British Company of Burgess House, Coventry Road, Birmingham, England do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed to be particularly described in and by the following statement: This invention relates to safety apparatus for restraining a seated occupant in a vehicle. More particularly, the safety apparatus includes lower torso restraint means, normally positioned about the lower torso of the occupant, and panel means moved from a store position to a restraint position in front of the occupant's chest as a result of vehicle deceleration. The invention may be considered as an improvement in, or relating to, the invention described in our U.K.

Patent Specification No. 1519678.

U.S. Patent Specification No. 3975037 describes a child safety device in which a deformable air bag is attached, by means of loops, to a restraining belt. In the event of rapid vehicle deceleration, the child moves forwardly of the vehicle seat so as to compress and thereby deform the air bag which is then raised in front of the childs body. However, the upright deformed position of the air bag (shown in Figure 2 of the U.S. Patent Specification) may not be maintained under load. In this case, the air bag will deform even more and allow the body to travel further in the forwards direction without properly restraining its forward motion. In other words, the body can bend forwardly from the waist with the chest bearing downwardly on the deformed air bag and hence the childs head may strike the front seat of a vehicle in which the air bag device is fitted at the rear. This problem would be worse in the case of adults because of the size of an adults body and the forward shift resulting therefrom. This is why safety apparatus with a form of chest restraining panel has not hitherto found ready application in the case of adults where the relative height of the chest panel is even more important.

The invention described in our U.K.

Patent Specification No. 1519678 overcomes this problem by providing a safety apparatus in which rigid panel means pivot upwardly from the stored position to an operative position before the chest of a vehicle occupant, so as to prevent excessive forward displacement of the occupant, without the occupant losing any comfort or being adversely affected. More particularly, the latter invention provides safety apparatus for restraining an occupant in a vehicle seat, the apparatus comprising lower torso restraining means defining a space to receive the thighs of said occupant, said lower torso restraining means including rigid panel means pivotally mounted thereon, said panel means being capable of pivotal movement from a stored position on said lower torso restraining means into an operative position before the chest of said occupant; and a strap at each side of said lower torso restraining means for anchoring said lower torso restraining means to the vehicle whilst enabling limited inertial movement of said lower torso restraining means, relative to said vehicle seat, due to vehicle deceleration; each of said straps being attached to a respective point on said panel means, or to lever means arranged to pivot about an axis on said restraining means against the lower torso of said occupant, the points of attachment being remote from the pivoting axis of said panel means whereby inertial movement of said occupant, relative to said vehicle seat, causes said lower torso restraining means to move away from said vehicle seat so that tension is applied to each of said straps to cause said panel means to pivot into its operative position before the chest of said occupant.

According to a preferred embodiment of the latter invention, the panel means comprises a pivotally mounted panel which is caused to pivot into its operative position by levers located adjacent the panel, one at each side of the lower torso restraining means. Each lever has a guide over which the respective strap passes before being attached to a point on the lever remote from the pivoting axis of the panel means. When the lower torso restraining means moves away from the vehicle seat, the tension in each strap acts on the respective lever to cause the panel to pivot into its operative position and the levers then prevent return movement to the panel to the stored position. Whilst the levers act as stops to prevent such return movement, circumstances may arise in which the panel could be caused to move from its operative position, before the occupants chest, towards its lower or stored position. Such circumstances may occur when there are momentary jerky variations in the tension in the straps, the cause of which may be due to fittings on the straps. Heavy jerky variations may also occur, for example, in pile ups where the vehicle undergoes, in the course of time, widely varying accelerational and decelerational forces. Brief intermittent variations of the restraining forces may, in addition, be the consequence of the springy behavour of the vehicle seat. Thus, in these circumstances, the chest restraint may be momentarily impaired by brief variations in the restraining forces.

The present invention overcomes this problem by providing locking means for locking said panel means in its operative position so that it cannot return to its stored position despite any variations in the tension in said straps.

More particularly, the present invention provides safety apparatus for restraining an occupant in a vehicle seat, the apparatus comprising lower torso restraining means defining a space to receive the thighs of said occupant, said lower torso restraining means including rigid panel means pivotally mounted thereon, said panel means being capable of pivotal movement from the stored position of said lower torso restraining means into an operative position before the chest of said occupant, and a strap at each side of said lower torso restraining means for anchoring said lower torso restraining means to the vehicle whilst enabling limited inertial movement of said lower torso restraining means, relative to said vehicle seat, due to vehicle deceleration; each of said straps being attached to a respective point on said panel means, or to lever means arranged to pivot about an axis on said restraining means adjacent the lower torso of said occupant, the points of attachment being remote from the pivoting axis of said panel means whereby inertial movement of said occupant, relative to said vehicle seat, causes said lower torso restraining means to move away from said vehicle seat so that tension is applied to each of said straps to cause said panel means to pivot into its operative position before the chest of said occupant, the apparatus including locking means coupled between said lower torso restraining means and said panel means, said locking means enabling said panel means to be pivotally moved into its operative position but preventing return movement therefrom towards its stored position. The locking means may be embodied in the form of a pair of pivoted arms, preferably provided as a pair of arms on each side of said panel means, which pair of arms may be folded together in the stored position but which are locked in an unfolded position to secure said panel means in its operative position. Alternatively, said locking means may comprise ratchet means, preferably provided on each side of said panel means, engaged by a member which slides over the ratchet as said panel means is pivoted into its operative position but which is prevented, by the ratchet, from reverse movement. The ratchet means may include teeth which extend linearly on one or both sides of said lower torso restraining means.

Alternatively, said locking means may be embodied in the form of a plate having a circular cut-out centred on the pivoting axis of said panel means, the circular cut-out being arranged to enclose a spring loaded pawl which prevents return movement of said panel means after reaching its operative position. In such embodiments, a lever is preferably fixed to said panel means at each side thereof and adjacent its pivoting axis, the straps being attached to respective points on the respective levers remote from said axis. Such levers may be shorter than those described in our previous Patent Application, referred to above, because the purpose of such levers is only to cause said panel means to be pivoted into its operative position before the chest of the occupant where said locking means prevents any return movement.

The invention will become more apparent with regard to the following description of exemplary embodiments. In the accom panying drawings: Figures la-ld illustrate a known restraining apparatus and shows successive phases in the pattern of movement of an occupant restrained thereby; Figures 2a-2d schematically illustrate safety apparatus according to one embodiment described in U.K. Patent Specification No.

1519678 and shows successive phases in the movement of an occupant; Figures 3a and 3b illustrate typical lever means used in the embodiments of Figures 2, 4 and 5; Figures 4a and 4b schematically illustrate successive phases of occupant movement in safety apparatus according to a further embodiment described in U.K. Patent Specification No. 1519678 and show the use of an additional seat for a smaller child; Figure 5 schematically illustrates the phases of occupant movement of an embodiment similar to that of Figure 2 but used by a larger child or adult; Figures 6a and 6b show a side view, as a respective phases movement, of an embodiment according to the present invention which employs locking means to secure a chest panel in its raised position; Figure 6c is a section, on lines c-c, through a lever arrangement shown in Figure 6b; Figures 7a and 7b show the phases of movement of another embodiment, in accordance with the invention, employing locking means; Figures 8a and 8b show the phases of movement of a further embodiment, according to the invention, employing locking means: and Figure 8c shows the detail of a circular type locking means used in the embodiments of Figure 8a-8b.

Referring to Figures 1-5, a seat 1 is rigidly connected to the body (where shown) of a vehicle. An occupant 3, who may be a child or an adult, occupies the seat 1. The safety apparatus for restraining the occupant is denoted generally by reference numeral 5.

Referring to Figures 2 and 5, the safety apparatus comprises lower torso restraining means in the form of a tunnel shaped body 5b which supports a pivotal chest panel 5a.

The tunnel shaped body 5b may rest on the seat 1 or be supported by the thighs of the occupant. In no case, is the tunnel shaped body 5b rigidly connected to the vehicle seat.

Referring to Figure 4, the occupant is a child and the safety apparatus comprises an additional seat 4 which is freely supported on the vehicle seat 1. In this case, the chest panel 5a is supported on a fixed panel Sb which rests on arms 4a or on the thighs of the occupant.

Referring to Figures 6-8 which show further embodiments of the present invention employing locking means to secure the chest panel in its operative position, only the lower torso restraining means Sb and the pivoting chest panel 5a have been shown for clarity. It will be understood, however, that the lower torso restraining means Sb is of a tunnel shape, for example, similar to that used in the arrangements of Figures 2 and 5.

Referring more particularly to Figure 1 the known form of safety apparatus 5 comprises a generally tunnel shaped body secured to seat 1 by a belt 6 extending through a groove 7. The belt 6 extends on both sides of the body towards attachment points on the body of the vehicle (not shown).

Figure la shows the normal situation when the occupant is not subjected to any decelerational forces. However, in the case of an accident, when such forces act on the occupant, the inertia of the occupants body moves the body of the apparatus S forwardly on seat 1 until the belt 6 is taut (Figue lib), whereupon the lower torso is secured but the upper torso bends forward increasingly as shown in Figures 1c and ld. Such movement may lead to injury.

Figures 2a-2d show an embodiment of the invention described in U.K. Patent Specification No. 1519678 in similar phases of operation. However, in this case, the safety apparatus 5 comprises lower torso restraining means in the form of a tunnel shaped body Sb on which a chest panel 5 a is supported for pivotal movement in the direction of arrow 8. The panel Sa extends substantially horizontally, in a table-like fashion, in a normal or stored position as shown in Figure 2a. Its pivotal movement is caused by the action of lever means 19 which is located between the panel 5a and the body 5b. The lever means is shown in more detail in Figure 3 and comprises a member or members 22 which extend across body 5b and pivot about an edge 19a nearest the occupant. On each respective side of the seat 1, a strap or belt 7 passes over a guide 21 on the inner end of lever 19, nearest the occupant, and is attached to a connection member 21 at the outer end, remote from the pivoting edge 19a of the lever means 19.

The rearward edge 10 of panel 5a is provided with a cut-out shaped to fit the body of the occupant. The width of panel 5a, the size and pattern of the cut-out and its convex rounding upwardly and downwardly are such as to distribute the restaining forces acting on the occupant over the pelvis, stomach and lower rib cage to avoid inadmissibly high loadings in the stomach zone. The edge 10 enables the forward shift of the occupants body shown in Figures 2b-2d, when the decelerational forces act in an accident condition. In this case, the panel 5a pivots upwardly about an axis of rotation 11, which is remote from edge 10, towards the occupant's chest as belts 7 become taut (Figure 2b). Panel 5a is maintained in this position, by the belt tension acting on lever means 19, and acts as a stop to prevent return movement of panel 5a. Thus, the upper torso of the occupant is restrained before the occupant starts to bend forward as shown in Figures la-ld.

The width of panel 5a substantialy corresponds with the width of the occupants body and the depth corresponds substantially to the length of the occupants body between the pelvis and upper chest. Therefore, when the panel 5a is pivoted into its upward position, it extends from the thighs of the occupant to the upper part of the chest to form a large area of support to restrain the upper torso.

Figures 4a and 4b show the rest and final positions of another embodiment described in U.K. Patent Specification No. 1519678 in which a child 3 occupies the additional seat 4. In the illustrated embodiment, the chest panel 5a is pivotally supported on a fixed member or panel 5b. Panels 5a, 5b may form a unit which is placed over the childs thighs or which is supported by the arms 4a of seat 4. However, the chest panel 5b may also be pivoted on the arms 4a of seat 4. As in the embodiment of Figures 2a-2d, the panel Sa is pivoted into an oblique position before the occupants chest (Figure 6b) by lever means 19 attached to a belt 7 on each side of the seat 4. Each belt 7 passes over a guide 20 on lever 19 and is attached to a connection member 21. The operation of this embodiment will be apparent from the description of Figures 2a-2d.

Figures 5a and 5b show the rest and final positions of a similar arrangement in which the thighs of an adult 3 are restrained by a tunnel shaped body 5b and the chest is restrained by a panel 5a mounted for pivotal movement on body 5b (Figure 5b). As the construction and operation of this arrangement is similar to that described with reference to Figures 2a-2d no further description is necessary.

There now follows a description of the preferred embodiments of the present invention.

Referring to Figures 6a-6c, a chest panel 5a is pivotally mounted by a pivot pin Sc relative to torso restraining means 5b which has a tunnel shaped body as described above. A segmental shaped lever 23 is fixed at each side of the chest panel 5a. Each lever 23 has an arcuate surface 23a over which a respective restraining strap or belt 7 is guided, one end of the belt being fixed to a part 23b of the lever and the other end (not shown) being anchored to the vehicle. A releasable safety belt buckle may be inserted at a suitable point in the belt 7, although this is not illustrated. Whilst the illustrated embodiment employs a tunnel shaped body Sb, the concept described with respect to any of the embodiments shown in Figures 6, 7 or 8 may be applied to an additional childs seat (see Figure 4) supported by the vehicle seat (not shown). If tension is applied to belts 7, the chest panel 5a pivots upwardly about pin Sc from its storage position (Figure 6a) to its operative position (Figure 6b) in which it is inclined away from the occupant's chest but where it prevents excessive forward bending of the occupant and thereby restrains the upper torso of the occupant.

Locking means 28 are provided to secure the chest panel 5a in its operative position.

The locking means 28 comprises two arms 25a, 25b which are joined by a pivot pin 26b, one arm 25a being pivotally connected at 27a to the chest panel 5a and the other arm 25b being pivotally connected at 27b to the tunnel shaped body 5b. Pin 26b is fixed ta arm 25b and is guided slidably in a slot 26a in the lever 25a. In the region of the folding joint 26, the lever 25 a carries a lateral stop 26c. The distance between this stop 26c and the pivot pin 26b, together with the length of the slot 26a, are so adjusted, relative to one another, that mutual rotation of the arms 25a or 25b about the pivot pin 26b is possible when the arms unfold as the chest panel 5a is moved upwardly due to the tension in belts 7. However, when the chest panel 5a reaches its operative position (Figure 6b) the slot 26a moves down with respect to pin 26b, thereby shortening the effective overall length of the aligned arms 25a, 25b and lower end of lever 25a is locked against the stop 26c. Thus return movement of the chest panel 5a, towards its storage position, is prevented even if the tensile forces in belts 7 momentarily deline or are completely absent. The chest panel 5a can be subsequently returned, however. by pivoting the panel 5a towards the occupant to move slot 26a upwardly with respect to pin 26b, and by pushing the joint 6 forwardly to cause the arms 25a, 25b to fold.

The embodiment shown in Figures 7a and 7b uses a different locking means 28 in that the folding arms are replaced by a linear ratchet (having teeth 29) fixed to the tunnel shaped body 5b together with a levershaped pawl 30 pivotally connected at 30a to the chest panel 5a. Such a ratchet and pawl mechanism is fitted at each side of the tunnel shaped body 5b. The lever pawl 30 has a pin 30b at one end which is guided by slot 31, so as to ride over teeth 29, in the direction towards the occupant, when tension is applied to belts 7 to raise the chest panel from its storage position (Figure 7a) into its operative position (Figure 7b). The ratchet teeth 29 prevent movement in the opposite direction, thus preventing return movement of the chest panel Sa from the inclined position it has reached due to the tension in belts 7. If this is a position lower than its maximum upright position, the chest panel 5a will be raised further when more tension is applied to belts 7. The panel 5a may be returned by pivoting the panel 5a towards the occupant and by releasing pin 30b from the ratchet teeth 29 and holding the pin above the teeth as the panel Sa is lowered.

In the embodiment of Figures 8a-8c, the locking means 28 is installed directly adjacent one end of the lever. Such locking means 28 is fitted at each side of the tunnel-shaped body 5b and comprises a plate 42 fastened to body Sb. The plate has a circular cut out 42a coaxial with pin 5c.

Eccentrically, in relation to pin 5c, the segmental lever 23 carries a pawl 43 which is rotatable at 43a and whose locking teeth 43b bear against the edge of the circular cut out 42a (in the manner of a ratchet) under the force of a spring 43c. The plate 42, or at least the edge of the circular cut out 42a, is made of softer material than the pawl 43 so that the teeth 43b, which are directed away from the direction of rotation, will dig into the cut out 42a to prevent anticlockwise (as illustrated) rotation of the panel 5a. Thus, clockwise rotation (as illustrated) of panel 5a is possible to allow it to pivot from its stored position (Figure 8a) into its operative position (Figure 8b) but anticlockwise rotation is prevented. In other words, when tension is applied to belts 7, the panel 5a pivots into its operative position and return movement is prevented by the locking means 28. The respective pawls 43 may be provided with actuators (not shown) in the form of bosses, pins or the like by means of which each respective pawl can be urged, by hand, away from the circular edge of the cut out 42a, against the force of the spring 43c, in order to enable the chest panel 5a to be intentionally returned to its storage position. The circular cut out may alternatively be provided with a ring of teeth to cooperate with the pawl 43.

WHAT WE CLAIMS IS: 1. Safety apparatus for restraining an occupant in a vehicle seat, the apparatus comprising lower torso restraining means defining a space to receive the thighs of said occupant, said lower torso restraining means including rigid panel means pivotally mounted thereon, said panel means being capable of pivotal movement from the stored position of said lower torso restraining means into an operation position before the chest of said occupant; and a strap at each side of said lower torso restraining means for anchoring said lower torso restraining means to the vehicle whilst enabling limited inertial movement of said lower torso restraining means, relative to said vehicle seat, due to vehicle deceleration; each of said straps being attached to a respective point on said panel means, or to lever means arranged to pivot about an axis on said restraining means adjacent the lower torso of said occupant, the points of attachment being remote from the pivoting axis of said panel means whereby inertial movement of said occupant, relative to said vehicle seat, causes said lower torso restraining means to move away from said vehicle seat so that tension is applied to each of said straps to cause said panel means to pivot into its operative position before the chest of said occupant, the apparatus including locking means coupled between said lower torso restraining means and said panel means, said locking means enabling said panel means to be pivotally moved into its operative position but preventing return movement therefrom towards its stored position.

2. Safety apparatus according to claim 1 wherein said locking means comprises two pairs of pivoted arms, each pair of arms being mutually pivoted together, the remote ends of the arms being connected respectively to said restraining means and in said panel means, said mutual pivot comprising a slidable connection and a stop whereby the arms, when unfolded to align the axis of slidable movement, can slide relatively into a locking position to prevent said return movement of said panel means.

3. Safety apparatus according to claim 1 wherein said locking means comprises a ratchet and pawl device coupled between said restraining means and said panel means to enable movement of said panel means into its operative position but to prevent said return movement.

4. Safety apparatus according to claim 3 comprising a ratchet and pawl at each side of said panel means, said ratchet comprising a member defining a slot having a row of ratchet teeth along one edge, said member being fixed to said restraining means and said pawl comprising a lever pivotally mounted at one end on said panel means and having engagement means at its other end for the teeth on the ratchet.

5. Safety apparatus according to claim 1 wherein said locking means comprises a member fixed to said restraining means and defining a circular cut-out, and a pawl coupled to said panel means for engaging said cut-out whereby said panel means is free to pivot into its operative position but return movement towards said stored position is prevented by engagement between said pawl and said cut-out.

6. Safety apparatus according to claim 5 including spring biasing means for biasing

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. opposite direction, thus preventing return movement of the chest panel Sa from the inclined position it has reached due to the tension in belts 7. If this is a position lower than its maximum upright position, the chest panel 5a will be raised further when more tension is applied to belts 7. The panel 5a may be returned by pivoting the panel 5a towards the occupant and by releasing pin 30b from the ratchet teeth 29 and holding the pin above the teeth as the panel Sa is lowered. In the embodiment of Figures 8a-8c, the locking means 28 is installed directly adjacent one end of the lever. Such locking means 28 is fitted at each side of the tunnel-shaped body 5b and comprises a plate 42 fastened to body Sb. The plate has a circular cut out 42a coaxial with pin 5c. Eccentrically, in relation to pin 5c, the segmental lever 23 carries a pawl 43 which is rotatable at 43a and whose locking teeth 43b bear against the edge of the circular cut out 42a (in the manner of a ratchet) under the force of a spring 43c. The plate 42, or at least the edge of the circular cut out 42a, is made of softer material than the pawl 43 so that the teeth 43b, which are directed away from the direction of rotation, will dig into the cut out 42a to prevent anticlockwise (as illustrated) rotation of the panel 5a. Thus, clockwise rotation (as illustrated) of panel 5a is possible to allow it to pivot from its stored position (Figure 8a) into its operative position (Figure 8b) but anticlockwise rotation is prevented. In other words, when tension is applied to belts 7, the panel 5a pivots into its operative position and return movement is prevented by the locking means 28. The respective pawls 43 may be provided with actuators (not shown) in the form of bosses, pins or the like by means of which each respective pawl can be urged, by hand, away from the circular edge of the cut out 42a, against the force of the spring 43c, in order to enable the chest panel 5a to be intentionally returned to its storage position. The circular cut out may alternatively be provided with a ring of teeth to cooperate with the pawl 43. WHAT WE CLAIMS IS:

1. Safety apparatus for restraining an occupant in a vehicle seat, the apparatus comprising lower torso restraining means defining a space to receive the thighs of said occupant, said lower torso restraining means including rigid panel means pivotally mounted thereon, said panel means being capable of pivotal movement from the stored position of said lower torso restraining means into an operation position before the chest of said occupant; and a strap at each side of said lower torso restraining means for anchoring said lower torso restraining means to the vehicle whilst enabling limited inertial movement of said lower torso restraining means, relative to said vehicle seat, due to vehicle deceleration; each of said straps being attached to a respective point on said panel means, or to lever means arranged to pivot about an axis on said restraining means adjacent the lower torso of said occupant, the points of attachment being remote from the pivoting axis of said panel means whereby inertial movement of said occupant, relative to said vehicle seat, causes said lower torso restraining means to move away from said vehicle seat so that tension is applied to each of said straps to cause said panel means to pivot into its operative position before the chest of said occupant, the apparatus including locking means coupled between said lower torso restraining means and said panel means, said locking means enabling said panel means to be pivotally moved into its operative position but preventing return movement therefrom towards its stored position.

said pawl towards said cut-out.

7. Safety apparatus according to claim 6 wherein said pawl and said spring biasing means are supported by said lever means and wherein said member is a plate having said circular cut-out, said plate being fixed to said restraining means and being made of softer material than said pawl whereby said pawl digs into the edges of said cut-out to prevent said return movement.

8. Safety apparatus according to claim 1 wherein said lever means comprises a segmental shaped lever fixed, one at each side, to said panel means; the respective strap passing over an arcuate portion of the associated segmental lever and being attached to a point remote from the lever pivot.

9. Safety apparatus for restraining an occupant in a vehicle seat and substantially as herein described with reference to Figures 6a and 6b of the accompanying drawings.

10. Safety apparatus for restraining an occupant in a vehicle seat and substantially as herein described with reference to Figures 7a and 7b.

11. Safety apparatus for restraining an occupant in a vehicle seat and substantially as herein described with reference to Figures 8a-8c.