WO1997008023A1

WO1997008023A1 - Safety belt system for a vehicle

Info

Publication number: WO1997008023A1
Application number: PCT/FI1996/000454
Authority: WO
Inventors: Matti Elias Ingemar Panelius; Timo Jaakko Andreas Panelius
Original assignee: Matti Elias Ingemar Panelius; Timo Jaakko Andreas Panelius
Priority date: 1995-08-23
Filing date: 1996-08-23
Publication date: 1997-03-06
Also published as: FI953945A0; FI953945A; AU6702796A; FI99102B; FI99102C

Abstract

The invention relates to a safety belt system for a vehicle comprising two separate safety belts (5). The free ends of each belt is secured to a buckle (6) with which the belts are secured together.

Description

Safety belt system for a vehicle

This invention concems the safety belt system of a motor car or other vehicle and especially a system in which the safety of the driver/passenger is considerably enhanced by the appropriate and enlightened design and positioning of the safety belt.

One of the most common safety belt systems currently in use is the "three-point safety belt", in which a safety belt is firmly attached to a door column of the vehicle at one end, for example, while at the other end it is attached to a point where there is a spring mechanism to wind the belt up. The belt has a sliding clamp which clamps into a fixed point on the other side (vis-a-vis the first attachment points) ofthe person held by the belt. Two belt parts cross the person's pelvis and chest. The belt is therefore attached at three points, and hence the name "three-point" safety belt.

The solutions employed in motor sports are so-called sports belts with four to six attachment points. The person is held by separate belts - one over each shoulder, and one or two belts between the legs - which are all attached to the car chassis. The belts are normally fastened to each other in the area of the person's pelvis.

One solution also exists employing a seat design in which the joint between the sitting part and the seat back is transferred a significant distance forward from its normal position. In addition, the sitter also uses a safety belt design consisting of two separate loops which are attached to the car chassis behind the seat, or to the frame structure or sitting part of the seat.

Various other solutions are also known, which have failed to reach the practical implementation stage due either to their complicated design or uncomfortable fit or excessive cost or weight. Many well-known solutions are further hampered by the fact that they do not, after all, provide sufficient protection in a crash situation. The purpose of this invention is to make an improvement to the safety problems which have been evident for some time now in the earlier technology and also to improve the distribution of impact forces in a crash situation. Additionally, the intention is to create a solution which allows the design of safe seats of normal weight, as well as facilitates the use of standard reels and belts with any possible safety belt tensioners.

The above mentioned and other benefits and advantages are achieved as are here presented as characteristic of the invention in the attached patent claim.

The invention is described in more detail in what follows, with reference to the attached drawings in which:

Figure 1 presents a side view of one embodiment of the invention in its main features;

Figure 2 presents a perspective view of the same structure;

Figure 3 presents a diagram of the prevalent impact forces in a system according to the invention in a crash situation;

Figure 4a presents a schematic diagram ofthe way to lead the safety belt according to the present invention;

Figure 4b shows the way to connect the belt to a buckle;

Figure 4c shows an alternative way to make the connection to the buckle;

Figure 5a presents an alternative of the belt's passing; and

Figure 5b is a representation, equivalent to that of Figure 4b, of the connection to the buckle.

Figure 1 , therefore, is an exemplary and schematic presentation of the basic principle of a safety belt system according to the invention. It shows the seat 1 of the vehicle, made up of the usual elements of a sitting part 2 and a seat back 3. The seat is attached by means of a suitable frame 4 to the car chassis, which is not shown herein in detail.

One of the basic principles of a safety belt system according to the invention is to employ two separate reel belts to hold a person in the seat 1. The belts 5 run, appropriately guided, over each shoulder of the person sitting in the seat 1 and the separate belt loops are suitably fastened together by means of a buckle 6.

The main danger with the previous two-belt solutions has been the risk ofthe buckle moving upwards causing the person to slip out from undemeath the belt. In this invention this problem has been prevented in the following way. The reel unit 51 ofthe reel belt is attached, for example, to a location in frame 4 of the seat 1 shown in Figure 1 , or to the vehicle floor. The belt 5 comes, in its first section 52, up to the buckle 6, and passes through the buckle, making a turn to come down diagonally in its second section 53 to the fastener 7, which is located distinctly further back than the reel unit 51. It then travels through the fastener 7 and comes up in its third section 54, as shown in Figure 1 for example, concealed within the seat back, to its top portion 3, from where it is guided through suitable guides in its fourth section

55 back down towards the buckle to which it fastens. Thus, the forces affecting the belt on impact are evenly distributed.

Figure 2 presents a similar solution to that shown in Figure 1 , but with both belts 5 visible. As is evident from the figure, the person sits down, slips both belts 5 over his/her shoulders and fastens together the two halves of the buckle 6.

Appropriate guides can be used to lift the belts from the front surface of the seat back in the shoulder region to make the belts easier to put on and also to make getting up from the seat easier. In an advanced version these guides could operate hydraulically and/or electromechanically, activated by the body weight ofthe seated person.

Figure 2 also shows part of the conceived frame structure of the seat. Thus, the frame 31 , 32 of the seat back of the seat could be made up of profiled steel, as shown, with the joint to the sitting part brought forward.

Figure 3 presents a theoretical calculation of certain forces which develop in a standard impact test, where the person's mass is 75 kg and the acceleration 30 G. In a head-on collision situation the impact force directed to one buckle link at the buckle position is in the region of 7.9 kN. According to the same calculation, the force directed from point A to point B is 7.9 kN, and from point A to point C approx. 11 kN. The force between the buckles is 7.3 kN and the force from point A to point D is calculated as zero. Friction has been assumed in the calculations to be nil.

Figures 4a and 5a show two alternative ways to lead the safety belts according to the invention. In Figure 4a is shown, schematically, the loops of the belt as they run in the alternative which has been described above in detail. However, there is also another alternative way which has been described in Figure 5a. A more detailed presentation ofthe connection ofthe belts to a buckle 6 is shown for each embodiment in Figures 4b and 5b and an altemative embodiment for the connection is shown in Figure 4c.

The figures are believed to be self-explaining. In both embodiments the belt ends in a buckle which is approximately on the stomach of the driver.

Collisions are all unique in their character and the forces of impact which come to play in collision situations do, therefore, vary greatly. Certain presumptions can, however, be made on the movements of the seat and the person seated in it in a collision situation. Dependent on the desired effect, a seat belt system according to the invention can be adapted by, for example, varying the fixing locations of the safety belt reels to the frame structure.

A safety belt solution according to the invention can also influence the structural dimensions. Thus, it has been calculated that, with a solution according to the invention, essentially normal seat weight can be achieved. For example, the type of seat back frame presented in Figure 3 would only weigh approx. 3 kg.

A safety belt system according to the invention can, if desired, employ various pieces of equipment to ensure that the safety belt is tight when the vehicle is affected by strong enough deceleration forces. There are many versions of such equipment, i.e. safety belt tensioners, available on the market.

One further important advantage of the invention is that it facilitates the use of normal standard reel belts only modified in that the "free" end of the belt is attached to the buckle and not to the frame structures.

The invention is, of course, not limited only to the embodiments described, but the invention can be altered and adapted in many ways within the framework of the attached claims. Thus, for improved safety and user comfort, various solutions can be employed, some of which relate to the design of the seat to be used with a safety belt system according to the invention.

As the first adaptation, the use of an extra belt can be presented. This extra belt or part of a belt comes up between the seated person's legs from the floor or chassis structure and can be attached to buckle 6, for example, or to a separate buckle. In another instance, the belt could be suitably located in a recess within the sitting part of the seat or it could be attached to a suitable place elsewhere, such as the seat frame, for example. The extra belt could also be bifurcate. When using a safety belt system according to the invention it is beneficial, due to the great variation in the sitters' heights, to provide a facility by which the relationship between the sitter's height and the upper belt supports can be adjusted. Byway of example, this facility could be provided by installing into the seat back frame a suitable track system, along which the sitting part and the seat back can be raised and lowered. Several alternative raising and lowering systems are available, such as jack-type hydraulic systems, electromechanical systems or manually lockable adjustment systems.

The invention can also include placing the reels along the same axle which runs from the reel on one side ofthe seat to the reel on the other side of the seat. This way, instead of two mechanisms, only one mechanism can be used also with regard to the belt tensioner. Departing from the afore presented embodiments, the belt reels can also be located in the frame structure forward of the seated person, in which case the belts come up from the reels between the sitter's legs.

To provide against side impact collisions in particular, it is also possible to place the seat on absorbent dampers. One altemative is to locate the fixing points of the seat in a liquid-filled, box-like unit fitted with an impact damper, which yields in impact situations and thus cushions the movement. A perforated unit may be placed in the liquid, for example, and the impact of collision will change the amount of liquid inside it. This type of absorbent damper is used, for example, in the keels of boats to cushion collision impacts.

Claims

1. A safety belt system for a vehicle which can be installed into the vehicle seat (1 ) and consists of two safety belt loops/safety belts equipped with a buckle or equivalent fitting (6) for the purpose of attaching them to each other, characterized in that the free end of the belt loop which starts from the reel (51) and passes through the clamping buckle (6), through the support fastener (7) and through the upper portion of the seat back (3), is fastened to the buckle (6).

2. A safety belt system according to claim 1 , characterized in that the belt loop passes first through the clamping buckle (6), then through the support fastener (7) and finally through the upper portion of the seat back (3).

3. A safety belt system according to claim 1 , characterized in that the belt loop passes first through the clamping buckle (6), then through the upper portion of the seat back (3) and finally through the support fastener (7).

4. A safety belt system according to claim 1 , characterized in that the reels (51 ) of the belts are located on one and the same axle which runs from one side of the seat to the other, thereby making the utilization of joint operating and tensioning mechanisms possible, if desired.

5. A safety belt system according to claim 1 , characterized in that the belts consist of two reel belts of a standard design.

6. A safety belt system according to claim 1 , characterized in that the reels (51 ) of the belts are attached to the structural frame of the vehicle or seat in the area almost directly below the buckle (6) of the belt (5) when in its use position, from the side view of the seat.

7. A safety belt system according to claim 1 , characterized in that the fastener (7) is located in the area below the seat back (3), attached to the frame structure.

8. A safety belt system according to any of the foregoing claims, characterized in that each belt is equipped with a so-called safety belt tensioner.

9. A safety belt system according to any of the foregoing claims, characterized in that it includes one or two extra belts which are fastened to the frame structure and come up between the sitter's legs for fixing to the buckle (6) or to a separate buckle.

10. A safety belt system according to claim 1, characterized in that it is used with such seat frame structures in which the joint between the sitting part and the seat back (3) is transferred a significant distance forward from the normal position.

11. A safety belt system according to claim 10, characterized in that it is used with such seat frame structures which allow for the positions of the sitting part (2) and the seat back (3) to be adjusted in relation to the upper belt supports.