The present invention generally relates to a method and a device designed to remove influencing forces during strong decelerations, e.g. during collisions with vehicles, by transmitting the influencing forces from e.g. a deforma¬ tion zone or various types of parts in a means of convey¬ ance to an extended load removal path, located outside this zone, the influencing forces formed during the col¬ lision being removed much faster than what has been pos¬ sible so far.

A deformation zone is in this context e.g. a shock absor¬ ber in a vehicle, a compressible safety or protection de¬ vice, which has been built into the vehicle, an intentio¬ nally designed deformation portion of the vehicle, etc.

The object of the present invention is to suggest a load removal of the influencing forces on the vehicle during a collision to such a low level of the deceleration force or braking force as is possible, in order to protect in an optimal way human beings, animals and objects in the vehicle against various injurious and damages, which usu¬ ally result during strong collisions.

The invention can be applied and used in existing vehicles or be mounted in the vehicle, when it is manufactured, but it is also obvious, that the invention also can be used in many other connections, in which there is a need to bring objects to a guided and controlled standstill in connection with strong decelerations.

The invention is based on the insight, that in many emer¬ gency situations with vehicles, e.g. collisions, it is desirable to be able to provide a certain load removal path for the shock produced during the collision, inside the vehicle itself as well as on the exterior of the ve-

hide, in order to attain a load removal. This has beendone so far by designing the vehicle with a comparatively soft shock receiving zone in the front part and/or in rear, which zone (zones) pick up the collision forces, when these shock receiving zones are compressed, e.g. folded like a concertina.

Many different devices are known, designed to produce a soft and harmless energy absorption, particularlywhen the device is used in vehicles. Such a device is known e.g. through Swedish p.appln. 7607029-1, according to which a shock energy absorption is done by flattening out a plurality of corrugated strips, placed on top of each other.

Another device is known through Swedish p.appln. 7700800-1, according to which en energy absorption is done by flat¬ tening out a block composed of cells.

In these two cases the load removal or the absorption of the shock energy during a collision is done along a pre¬ determined and thereby limited load removal path, namely by flattening out the corrugated strips and the block of cells respectively.

These devices are designed and dimensioned to cope with a certain predetermined collision force, corresponding to a certain speed and a certain mass of the vehicle, but they cannot, in a satisfactorily functioning way, cope with collisions, in which the collision force, i.e. the speed and the mass of the vehicle, considerably deviates from the collision force, which has been calculated in advance. A substantially stronger as well as a substan¬ tially weaker actual collision force than the calculated collision force yields a disadvantageous result. Serious injuries and fatal accidents, which often happen during collisions, are proofs, that known devices do not work satisfactorily.

One of the reasons, why known shock receiving zones func¬ tion unsatisfactorily, is that the load removal or the absorption of the force, which is produced during a col¬ lision, increases as to strength and varies as regards the increase in this strength, and this results during a collision in an unsufficiently utilized load removal path or time.

The forces which a vehicle is subjected to or which a per¬ son, who is fastened by means of a safety belt, is subjec¬ ted to during a collision can be defined as is shown in the form of an example in Fig. 1. Load removal time t is indicated along the X-axis and the deceleration force or the load removal force F in the vehicle or on the person in the vehicle is indicated along the Y-axis. It is shown that force F, when the collision takes place, increases strongly, up to a certain maximum with a certain increase variation, and then the force is maintained with a rela¬ tively strong variation during a certain period of time, and finally it decreases relatively strongly and with a variation to a zero value. During times tl, shown in the diagram, i.e. during the initial force increase, which pre¬ sumably happens during the tightening of the safety belt, during the considerable variations between the shown force maxima, which presumably are obtained due to the rolling effect of the safety belt, and during, the final decrease of the force, the load removal force is inefficient, and a truly efficient load removal only takes place during the two periods of time t2, indicated in the diagram.

It would be desirable to be able to "spread out" the shown time/force curve, in order to decrease the inefficient times tl and increase the efficient times t2 and thus to be able to utilize the total load removal time tl + t2 in a more efficient way.

In Fig. 2 the ideal load removal curve is shown, the load removal force being constant during the entire load remo-

val time. The theoretically most favorable curve, shown in Fig. 2, can never be attained, but instead according to the invention a load removal which is illustrated in Fig. 4 can be attained, whereby the inefficient initial time tl as well as the inefficient final time tl for the load re¬ moval have decreased to a minimum, whereas the efficient load removal time t2 is about as large as the total dece¬ leration time during the collision, the load removal being done with a constant force during the entire load removal time tl + t2.

In Fig. 5 all the three above-mentioned curves havebeen drawn in the same diagram, namely the influencing force- curve according to Fig. 1, the theoretically most favor¬ able load removal curve according to Fig. 2, and the ac¬ tually feasible most favorable load removal curve accor¬ ding to Fig. 4. It is clearly shown, that the force maxi¬ ma of deceleration curve 1 have been decreased substan¬ tially.

Also, a larger deceleration is required, when the speed of the car increases, and .the load removal time will of cource be shorter, if the speed of the car increases. This is shown schematically in Fig. 3, which shows a speed(v) / time(t)-diagram, the dimension of the deceleration corre¬ sponding to the inclination of the curve. Consequently, a load removal device must be designed in such a way, that also such a changing deceleration in taken into conside¬ ration.

The present invention is based on the discovery, that it is possible to strongly lower the risk of personal inju¬ ries as well as vehicle damages during strong decelera¬ tions, e.g. collisions, by automaticly transmitting the influencing forces, during an initial phase of a strong deceleration, from the body of the person fastened by the safety belt and from a deformation zone, built into the vehicle, e.g. from a compressible shock absorber, to

an extended load removal path, located outside this part of the vehicle, the influencing forces being removed in a controlled way by means of a load remover in a very large number of minor load removal steps or phases with brief resting periods after each such minor load removal step. The load removal of the influencing forces is in this way done without any locking, which means that the influencing forces also cannot be stopped abruptly during the load re¬ moval of the vehicle, independent of the speed of the ve¬ hicle during the collision, whereas this happens often during strong collisions, when conventional known pro¬ tection and safety devices in vehicles are used.

Since the load removal in the form of said minor load re¬ moval steps is done along the extended load removal path, they will more or less be compressed against each other along the available short load removal path of the body and the vehicle respectively to a constant load removal or braking force.

The size of the constant load removal or braking force on the existing load removal path can be limited to such a value, that a relatively satisfactory protection can be obtained, also when a collision is extremely strong.

In another embodiment of the invention the force along the load removal steps can be increased or decreased, de¬ pending on the speed of the vehicle. Alternatively or si¬ multaneously with this the deformation zone of the vehicle, e.g. a movable shock absorber, can be designed in such a way, that it during various speeds automaticly is displaced outwards to a certain increased length, and in this way the vehicle will have more time to be load removed during a collision. The displacement of the deformation zone of the vehicle can e.g. be done hydraulicly or by means of any other known suitable means. This enlargement of the defor¬ mation zone can also be used to obtain an improved lateral collision protection etc.

In this way it is possible to manufacture also compara¬ tively small cars, which during a collision provide a con¬ siderably better collision protection than what the mo¬ dern "safest cars" can provide.

Thus, the present invention renders it possible to build safer cars, which during collisions cause less injuries and damages to passengers and materials respectively.

The basic idea of the invention is to unload the vehicle with a constant load removal force during a collision but without a locking of the influencing forces caused by a collision during the load removal, all the available load removal time at the same time being utilized in an effici¬ ent way and the inefficient load removal rime tl being re¬ duced to a clear minimum.

The above-described successive, locking-free load removal is done along a considerably enlarged and not limited load removal path and can be done in a mechanical, hydraulic, pneumatic, pyrotechnical, magnetic or electric way or in any other way, but for the sake of simplicity the inven¬ tion will be described mainly with reference to a mechani¬ cal solution of the problem in the form of a load remover/ load limiting device, connected to a compressible shock absorber, built into the vehicle, but it is obvious, that the invention also can be used in many other connections, in which there is a need to, in connection with strong col¬ lisions, provide a load removal in a controlled way.

The invention will now be described in more detail with reference to the accompanying drawings, in which Fig. 1, as has been explained above, shows a deceleration curve of a vehicle without a load removal device; Fig. 2 shows an ideal curve for the load removal. Fig. 3 shows a speed/ deceleration curve. Fig. 4 shows an actual load removal curve for the system according to the present invention; and Fig. 5 shows a combination of the curves in Figs. 1,

2 and 4. Fig. 6 shows a load removal unit, which is connec¬ ted to a force transmitter, which is shown in Fig. 7, which in its turn is connected to a force receiver, which is shown in Fig. 8. Fig. 9 shows a section of a detail of the device according to Figs. 7 and 8. Fig. 10 shows in a fragmentary planar view an embodiment of a device according to the in¬ vention; and Fig. 11 shows a lateral view of the device in Fig. 10. Fig. 12 shows in perspective a resilient roll, de¬ signed to be used in the device according to the invention. Fig. 13 shows a curve illustrating the influencing force in relation to the braking force, when a strip or a cable is unwound from the load removal unit in Fig. 6. Figs. 14 and 15 show schematicly the moment arm enlargement in the de¬ vice according to Fig. 6. Fig. 16 shows the situation du¬ ring a collision with a vehicle according to the state of the art; and Fig. 17 shows in a similar way the situation during a collision with a vehicle, which is equipped with a load removal device according to the present invention in connection with a schematicly illustrated function of the load removal along the enlarged load removal path ac¬ cording to the invention.

The load removal device shown in Fig. 6 comprises a rotary disk, provided with a plurality of radially disposed cone- shaped elements, called cone disk 1 in the following text, as well as a non-rotary mating disk 2, which interacts with the cone disk. Cone disk 1 is, on its side which faces ma¬ ting disk 2, provided with a plurality of load removal paths 3 in the form av lines of cone elements. Non-rotary mating disk 2 is designed in such a way, that it can be pressed towards rotary cone disk 1. There are active rolls 4 between load removal paths 3 of cone disk 1 and mating disk 2, e.g. of the type shown in Fig. 12. Rolls 4 are con¬ nected to mating disk 2 and retained against this disk, and they are designed to, when a strong vehicle decelera¬ tion occurs, produce a very often repeated or frequent, successive and non-locking load removal in the form of a plurality of minor load removal moments and subsequent to

each such load removal moment a very brief load removal rest period.

As is clearly shown in Figs. 10 and 11 load removal path 3 on the surface of cone disk 1 can be lines or paths 5 of cone-shaped load removal elements 6, called cone paths 5 in the following text. Rolls' 4 bear on cone elements 6 or the cones with a resilient pressing. As is shown in Fig. 11, each roll element can be composed of several, e.g. three, rolls 4, which form an interacting unit, rolls 4 in the shown case being somewhat displaced in relation to each other, a first roll of the unit bearing on a cone bot¬ tom, when a second roll rolls on inclined running surface 7 on a cone 6 and a third roll bearing on the following cone top 8 and being ready to be load removed through a rolling against downwardly or radially inwardly running release surface 9 on a cone element. When cone disk 1 is rotated in relation to non-rotary mating disk 2 spring- loaded rolls 4 will produce frequent, minor load removal moments, and subsequent to each such minor load removal a load removal rest period follows. The load removalpath on cone disk 1 can alternatively be a plurality of cone paths, which are somewhat displaced in relation to each other, and in this case the spring-loaded rolls are placed in a radial line adjacent each other along the cone paths.

Thus, cone paths 5 are designed with a slowly rising run¬ ning surface 7, which ends in a rounded top 8 and is fol¬ lowed by a strongly falling release surface 9. Spring-loa¬ ded rolls 4 bear and roll on the cones, when cone path or cone paths 5 rotate. Rolls 4, which are active between cone disk 1 and mating disk 2, will, when cone disk 1 ro¬ tates in relation to mating disk 2, be successively pressed against cone disk 1 during the rolling on running surfaces 7, against the influence by spring-loading 10, as is shown in Fig. 11, and will subsequently roll over top 8 of the cone and downwards along its release surface 9. The rol¬ ling along running surface 7 requires a certain force.

which is derived from the transferred deceleration force. Subsequent to this counteracting load removal force a certain rest period will arise, during which rolls 4 roll downwards along release surface 9 of the cone.

Cone disk 1 and mating disk 2 are axially mounted in re¬ lation to each other on sun-wheel shaft 11a of a planetary gearing, and disks 1 and 2 and the planetary gearing are supported by stationary base 12. Cone disk 1 is fixedly mounted on sun-wheel shaft 11a and can be rotated jointly with the shaft, but it cannot be axially displaced in any direction. Mating disk 2 is non-rotationally mounted but displaceable on sun-wheel shaft 11a to the left, as is shown in Fig. 6. Mating disk 2 is kept non-rotational by means of a couple of guide pins 13, which are slidable in corresponding holes in a fastener 14 in base 12. Sun-wheel shaft 11a is threaded 15 and the non-rotary mating disk 2 is threaded too, and consequently it will, when shaft 11a rotates according to the arrow in Fig. 6, be screwed to the left, as is shown in the figure, to obtain a succes¬ sively stronger pressing of rolls 4 against cone paths 5 of rotary cone disk 1.

Planetary wheel shaft 11 of the planetary gearing is ro- tationally mounted in the base, and on planetary wheel shaft 11 a strip 16, e.g. in the form of a metal strip is wound. Strip 16 is, with its opposite end, connected to a load transmitting element 17, which is shown in Fig. 7, which element in its turn is connected to a shock-recei¬ ving element 18, which is shown in Fig. 8.

Metal strip 16 is in its normal condition wound on plane¬ tary wheel shaft 11. If a collision takes place, shock re¬ ceiver 18 is influenced by a pressing of some part of the vehicle, e.g. a deformation zone 19, such as a shock ab¬ sorber, the pressing moment immediately being transmitted to load transmitting element 17 in the form av a pulling moment, which in its turn is directly transmitted to the load removal device in Fig 6 through an actuation of me-

tal strip 16, the latter being pulled outwards. In this way planetary wheel shaft 11 will, via the planetary wheels, ro¬ tate sun-wheel shaft 11a jointly with rotary cone disk 1 with a speed, which is higher than the rotary speed ofpla¬ netary wheel shaft 11. When sun-wheel shaft 11a is rotated, non-rotary mating disk 2, which is thread-connected to sun- wheel shaft 11a, will at the same time be screwed towards rotary cone disk 1 and in this way provide a successively increased pressing of the mating disk and its spring-loaded rolls 4 against cone disk 1.

Shock receiver 18 can be designed in many different ways, but according to Fig. 8 it comprises a hollow supporting part 20, which is fixedly connected to deformation zone 19, e.g. the shock absorber, and which slidably is guided on a solid supporting part 21, which is fixedly mounted- in the vehicle. On hollow supporting part 20 a guide roll 22 is mounted, and on each side of hollow supporting part 20 a second stationary guide roll 23 and 24 respectively is mounted. On top of solid supporting part 21 a yoke 25 is provided, which with its ends supports a pulling wire 26, which runs in a loop around and below the two stationary guide rolls and around and above intermediate guide roll 22 on hollow supporting part 20.

It is shown that the deformation zone, e.g. shock absorber 19, which is one of many feasible embodiments, is a shock receiving element, which is made of modules, comprising a number of strip parts 28, which in an unloaded condition are flat, as well as between each couple of such flat strip parts mounted angle-bent or corrugated strip parts 27, which are easily disengageably fastened to flat strip parts 28, and which are joined to each other in such a way, that they, when the receiving element is loaded, can be flat¬ tened out and be angularly bent or corrugated respective¬ ly repeatedly, without a locking of the strip parts du¬ ring a loading.

Yoke 25 supports also between its ends by means of pulling wire 26 a load transmitting wire 29, which is slidable in a compressionresistant casing, which can be bent in there- quired shape when pulling, up to load transmitting element 17, e.g. a so called Bowden cable 30, which is partially shown in Fig. 9 and which is fastened in load transmitting element 17 in Fig. 7. The vehicle can be designed with se¬ veral deformation zones, e.g. two in the front part, two in rear and one on each side, and every such deformation zone can, by means of its load transmitting wire 29 and Bowden cable 30, be connected to one and the same load transmitting element 17, which consequently receives four wires, designated a,b,c and d in Fig. 7. Wires 29 are con¬ nected to a slide carriage 31, which is displaceable in¬ side a stationary load transmitting housing 32, e.g. via slide rolls 33. Pulling strip 16 from the load removal de¬ vice is fixedly connected to slide carriage 31, a displace¬ ment downwards of the slide carriage resulting in a simul¬ taneous unwinding of strip 16 from spindle 11 and then al¬ so a rotation of cone disk 1 and a displacement of mating disk 2 towards cone disk 1.

Planetary gearing 35 with its spindles 11 and 11a as well as the planetary wheel and sun-wheel (not shown) provide, due to the increase in the rotary movement of cone disk 1 in relation to planetary wheel spindle 11, on which pul¬ ling strip 16 is wound, an extension of the load removal path, and the quickly rotating sun-wheel spindle 11a pro¬ vides a very quick displacement of mating disk 2 towards cone disk 1. In Fig. 14 it is shown that the increase in the rotary movement of the load removal path in relation to the winding spindle 11 for the pulling strip 16 is four times.

It should be observed in this connection, that the device can include an element, which detects the speed of the ve¬ hicle and the load removal moment of this speed, a strong¬ er load removal being obtained at higher speeds than at

lower speeds.

Fig. 13 shows in a diagram, how a shock force against the deformation zone, e.g. shock absorber 19, indicated along the Y-axis, results in an unwinding of strip 16 from the spindle in the load removal unit in Fig. 6, indicated along line 34, and results in a load removal force, indicated along the X-axis in the figure. The load removal principle according to the present invention implies, that during a collision a controlled locking-free load removal is ob¬ tained, which is automaticly adjusted to varying colli¬ sion forces, which means that the load removal device al¬ ways removes such a large amount of force as is required as regards the collision force.

Figs. 14 and 15 show, how the length which metal strip 16 is unwound from a spindle having a radius R (11) is multi¬ plied to a length corresponding to a radius R (1) of cone disk 1, and how this length is increased four times, de¬ pending on the 4-fold step-up shifting of the rotation of planetary wheel spindle 11 in relation to sun-wheel spindle 11a. This is similar to an effect of a double-armed lever, the small force moment "m" on the right side in Fig. 15 being multiplied to the large force moment "M" on the other side of the two-armed lever.

Fig. 16 illustrates the compression of the deformation zones of a vehicle, which is obtained during a collision with a car designed in a conventional way. It is shown that the vehicle is compressed a distance a-b.

As a comparison, a collision during identical conditions is shown in Fig. 17, with a car designed with a load re¬ moval device according to the present invention. It is shown that the compression in the latter case is done along a distance a'-b', which is considerably smaller than the previous distance a-b. Fig. 17 also shows sche¬ maticly, how the small compression distance a'-b" is mul-

tiplied on cone paths 5 of the load removal device to a distance A-B, which is many times larger than distance a'-b".

It is obvious, that the device described above can be built into vehicles, when they are manufactured. Also, it is obvious that the device can be used in vehicles, which do not comprise any built-in deformation zones, and in which the described device in such a case will consti¬ tute its own deformation device, e.g. connected to an in¬ wardly displaceable shock absorber or a similar device.

REFERENCE NUMERALS

1 cone disk, rotary 31 slide carriage

2 mating disk, non-rotary 32 load transmitting

3 load removal path housing

4 roll 33 slide roll

5 cone path 35 planetary gearing

6 cone element

7 running surface (6)

8 cone top (6)

9 release surface (6)

10 spring loading (of 4)

11 planetary wheel spindle 11a sun-wheel spindle

12 base

13 guide pin

14 fastener (in 12)

15 threads (on 11a)

16 strip

17 load transmitting element

18 shock receiver

19 deformation zone

20 supporting part (hollow)

21 supporting part (solid)

22 guide roll (on 20)

23 guide roll, stationary

24 guide roll, stationary

25 yoke

26 pulling wire

27 corrugated strip parts

28 flat strip parts

29 load transmitting wire

30 Bowden cable