SE463406B - PROCEDURE AND DEVICE FOR POWER LOADING BY THE SECURITY BELT BY POWERFUL RETARDATIONS - Google Patents

Description

465 lO l5 20 25 30 35 406 2 the trapped person is thrown forward and injured against the steering wheel, dashboard, windscreen or other hard parts of the vehicle. However, it is also known that a very tightly clamped person in the event of a strong deceleration, such as in a collision, may be exposed to very strong so-called g-forces, and in addition the person may be exposed to such strong pressure from the seat belt that serious bodily injuries can already arise from the influence of the seat belt.

Many different devices are known to effect a stretching of the seat belt in connection with a collision. Some such known devices are of the mechanical type, others are of the pyrotechnic type, the latter devices having the advantage that they react very quickly and within only a few or a few hundredths of a second achieve the desired tightening of the seat belt.

For example, a device for tightening a seat belt by means of a pyrotechnic charge in the event of an emergency is known from the Swedish publication 379,934 or the German publication DE-A-32 20 498. In both cases it is a question of achieve an unchanged stretching of the seat belt, which stretching can possibly take place in a couple of successive steps.

Such an unchanged stretching of the seat belt leads in the event of a violent deceleration of the vehicle to an equally strong deceleration of the fastened person, which in itself can be harmful, and in addition a strong tightening of the seat belt can cause pressure damage and other injuries to the fastened person.

The invention is based on the discovery that the risk of injuries in the event of severe deceleration can be greatly reduced by initially causing a severe tightening of the seat belt, after which a certain number of subsequent relief tempos are preferably achieved in a plurality, perhaps a large number of subsequent relief tempos or even gives the body the opportunity to move an insignificant distance forward followed by a resurrection or a certain slight re-tightening of the seat belt.

This can be achieved by detonating a first, relatively strong pyrotechnic charge primarily to provide a stretch of the seat belt, followed by a plurality, preferably a larger number of consecutive detonations of weaker pyrotechnics. technical charges, between which the seat belt is given the opportunity to slacken slightly, so that the restrained person is slightly relieved or, as a result of the force of gravity against the seat belt, is given the opportunity to move an insignificant distance forward before the next detonation causes this movement to stop or renew slight retraction of the seat belt. Through this series of short, fast and relatively weak, so to speak jerking detonations, instead of one or a couple of strong, one-sidedly acting influencing forces, the resulting g-force will be extended somewhat over time, which entails a significantly reduced risk of damage to the restrained person.

The described force relief can be achieved, for example, with a pyrotechnic control valve consisting of a fixed and a cooperating movable part, for example a piston-cylinder unit, containing a pyrotechnic serial charge consisting of a plurality of elementary charges arranged to detonate in turn when the charge is released. each other. The pyrotechnic control valve has primarily been added as the solution to the problem of achieving a certain function of a vehicle or means of transport in a very short time, in particular some type of safety function, and the invention will in the following mainly be described in connection therewith. However, it is obvious that the invention can be used in many other technical fields and for many other purposes, and that the invention is not limited to the described areas of operation.

The pyrotechnic charge can be designed and arranged so that it detonates in its entirety in a very short time, perhaps only within a few thousandths of a second up to any desired detonation time, and it can consist of from a few charges to a very large number of separately lying elementary charges arranged to ignite and detonate in turn one after the other. In an advantageous embodiment of the invention, the charges are adapted to the desired function, so that the elementary charges have different strengths, for example so that the first charge in the series has a high detonation force to effect the primary tightening of the seat belt, and that the subsequent 463 406 4 The charges have less, or even successively decreasing, increasing or surging detonation force.

Of course, the pyrotechnic valve can, if desired, be designed in a reverse manner, i.e. so that it gives a gradually increasing detonation force, or a gradually increasing and then gradually decreasing detonation force, or in any other "programmed" manner.

The pyrotechnic valve according to the invention can be used wherever desired step by step, in several smaller rounds relieving deceleration forces or kinetic energy.

The invention will now be described in more detail in connection with the accompanying drawings.

In the drawings, Figure 1 shows diagrammatically in a longitudinal section a pyrotechnic force relief device according to the invention, and Figures 2 and 3 illustrate in diagrammatic form how a device according to the invention can be arranged to function. Figure 4 shows a device according to the invention connected to a three-point seat belt. Figure 5 shows fragmentarily a detail of the system according to Figure 4, and Figure 6 shows a stage in the operation of the device according to the invention.

The pyrotechnic force relief device or valve shown in Figure 1 is in the example shown designed as a piston-cylinder device with a cylinder body 1, in which a piston 2 is displaceable from a normal bottom position, shown in Figure 1, next to a pyrotechnic serial charge 3 and a extended position, where the piston 2 is removed from the bottom position. At the shown upper end of the cylinder 1 there is a cylinder top or so-called piston catcher 4, which is suitably a separate part, which is threaded on the cylinder 1. The serial charge 3 consists of a number, preferably a large number, of elementary charges 5 of the same or preferably different power potentials, such as a first strong charge and then a larger number of weaker charges. The serial charge is arranged to be able to be initiated to detonate a schematically indicated ignition device 6, which may be mechanical or electrical and of a known type, and which in turn is connected to a trip activator, for example a mechanical or electronic deceleration sensor 7.

The serial charge 3 can be designed as a replaceable cartridge sleeve 10, which, for example with a bottom plate 9, is clamped against the bottom of the cylinder 1 by means of a nut 10.

The cylinder 1 can have varying length and shape depending on which function is desired. The cylinder top 4 and the top of the piston 2 are dome-shaped. The underside of the piston 2 can be hollowed out and adapted to the shape and size of the upper part of the series charge 3.

The cylinder head 4 is in the case shown formed with a small evacuation hole 11 for evacuating the air cushion when the piston is pushed upwards in the cylinder, and the cylinder is at some place near the cylinder bottom formed with one or more through evacuation holes 12 for discharging any excess gas and for enable a retraction of the piston 2 a larger or smaller distance between the detonation of the elementary charges and after the entire charge 3 has detonated. The evacuation hole 11 and / or the evacuation holes 12 may optionally be provided with (schematically indicated) single or double-acting spring-loaded valves to provide a limited free flow of gas out and / or in through the evacuation holes.

Attached to the underside of the piston 2 is a tow line 13, which can be used to perform the desired safety function. The purpose of the tow line 13 is partly to achieve a tightening of a seat belt, and partly also to limit the maximum projection of the piston 2 from the bottom position shown in figure 1 in the cylinder. The line 13 has a length that stops the piston some distance from the cylinder top, but if for some reason the line should come off, the cylinder top acts as a piston catcher and prevents the piston from being pushed out of the cylinder.

The towline 13 extends through an axial hole in the cartridge sleeve 8 and out through a central hole in the nut 1D. Alternatively, or in combination with the tow line 13, the piston on the upper side may have a projecting actuating rod 14 as indicated in Figure 1, which rod can directly affect any safety member in the vehicle.

The elementary charges 5 are of a per se known type and are arranged in layers one above the other or in a spiral and in such a way that they are triggered in succession one after the other, but within a preferably very short period of time of from a few thousandths of a second 463 406 6 10 l5 20 25 30 35 to any desired longer time. In the case shown, the intention is to trigger the elementary charges from above and below, but it is obvious that other solutions are possible. Thus, for example, the elementary charges can be arranged in a cavity in the piston, whereby they are triggered from below and successively upwards. The elementary charges can be designed larger or smaller in such a way that a certain desired function is obtained.

Thus, the elementary charges can be designed so that the first detonating charge or charges have a large force, while the subsequent detonations are weaker or successively weaker. Conversely, the element charges can be arranged so that the force increases or varies in a certain desired and programmed manner. Furthermore, it can be achieved that a small force gap arises between each detonation, so that the piston 2 has the possibility to stop or even return a small distance in the direction of its original position between each detonation. As a result, the piston 2 will gradually "chop" downwards or back to the initial position, whereby an improved effect with time-delayed deceleration and stepwise force relief can be achieved. By suitable design of the pyrotechnic serial charge 3, almost any desired function can be achieved.

Figure 2 illustrates in diagrammatic form what the function of a pyro-technical valve according to figure 1 can look like in practice. It is assumed in this case that the tow line 13 with its free end is attached to some device, which is to be successively tightened and relaxed, for example a seat belt. It is further assumed that the series charge 3 consists of a larger number of elementary charges arranged one after the other with different detonation forces, here denoted a, b, c, d, etc. In the diagram, the force has been deposited along the vertical axis and the time along the horizontal axis. It appears that the first elemental charge a produces a relatively large force a for a certain small time, whereby, for example, a seat belt is primarily tightened sharply. The piston can move unhindered upwards by the airbag exiting through the evacuation hole 11. When this detonation a has ceased, the clamped body is relieved slightly before the next detonation b is ignited. The explosion gases escape through the evacuation holes 12. In the case shown, the detonation b is considerably weaker than the detonation a, and the seat belt is tightened only insignificantly, after which a certain relief takes place until the next detonation c produces a renewed slight tightening etc. In this way, the seat belt can be slackened step by step until it has regained its original position, and thus the g-force on the fastened person has been extended in time and the maximum pressure that the seat belt exerts on the person has been gradually reduced. It should be emphasized that the total time for all detonations can be as short as only a few hundredths of a second, but that nevertheless a very good effect is achieved through the stepwise "chopping" force and pressure relief.

Figure 3 shows an alternative diagram, in which the first primary stretching of the seat belt is effected by means of a first strong detonation a, and also by a series of rapid small detonations a1, az ..., which for a certain short time keep the seat belt unchanged. . Then the above-mentioned stepwise "chopping" force and pressure relief begins.

The pyrotechnic device or valve shown in Figure 1 is suitable, for example, for tightening a seat belt and it is illustrated in such a function as one of many conceivable areas of use.

The device is for the purpose formed with a roller 15, on which the line 13 from the piston is wound, and from which the line is unwound when the piston is pushed upwards in the cylinder. The roller 15 sits on a stationary shaft 16, and on the same shaft a second roller 17 is mounted. Attached to this latter roller is a rope 18, which at its opposite end is connected to a tow link 19 to form a loop of a seat belt 20, as will be explained in more detail in connection with Figures 4-5. The lines 13 and 18 are counter-wound on their rollers, so that the line 18 is wound up on the roll 17 when the line 13 is wound by its roll 15 in connection with the serial charge 3 being fired. Thereby, the rope 18 will pull down the drawbar 19 and form a loop on the seat belt, which is thereby tightened around the fastened person, and at the same time the belt roller 28 is locked automatically.

In an alternative embodiment of the device in figure 1, a locking device is connected to the roller system 15-17, which device consists of a third roller 21, which is also mounted on the shaft 16 and is connected via a freewheel lock 22, and which is via a line 465 10 15 20 25 30 35 406 s 23 connected to a fourth reel 24, on which the line 23 is wound. Thanks to the freewheel latch 22, the unwinding of the line 23 from the roller 24 to the roller 21 can take place when the tow line 13 together with the piston 2 goes in the opposite direction, ie when the piston 2 moves downwards, and when the line 13 is rolled up on the roller 15 again. with this device is that the body can never move forward anymore. than that corresponding to the unrolled length of the line 23 secured by the roller 24.

Figure 4 shows the device according to the invention connected to a three-point roller car belt 20 at a stage when the deceleration force from the rider's body is gradually relieved in several smaller rounds. The device can just as well be connected to the two-point belts as to the 3- or 4-point belts, and it is also possible to use two or more devices according to the invention for one and the same clamped person, for example one for the chest strap part and one for the hip strap part, or connect a single device to both the chest and hip strap part, or connect a "central" device to two or more seat belts. Figure 4 shows, however, for the sake of simplicity, only one device which is connected to the chest strap part. It should be noted that the described device can also be easily connected to existing seat belts. Conveniently, there is an electrical safety contact that prevents the pyrotechnic device from tripping other than when the belt buckle is connected.

Figure 4 shows how the belt 20 from a belt roller 28 passes through three different deflectors, namely two fixed deflectors 25 and 26 and the above-mentioned traction deflector 19. As shown in Figure 5, the traction deflector is positioned so that the belt normally passes freely through it and only slides over the fixed deflectors 25 and 26. The pull deflector is easily releasably mounted in a holder 27, which releases the pull deflector as soon as a charge 3 is triggered, whereby the pull deflector is pulled down, whereby the body 29 of the clamped person can be clamped against the car seat.

Figure 6 shows an alternative embodiment of the invention, where the pyrotechnic valve is mounted in reverse to what is shown in Figure 1, and where it by means of the line 13 directly acts on the pull-around linker at a stage when the piston 2 gradually "chops" back to its original position, which is the position before the collision.

The function of the device in Figures 1-5 is as follows: In the event of a strong deceleration of the type preceding a collision, the deceleration sensor 7 initiates the ignition device 6 to produce an ignition of the pyrotechnic serial charge 3, the first, preferably powerful, elemental charge 5 detonating. The piston 2 is then pushed out and pulls with it the rope 13 (respectively pushes out the rod 14), which in turn causes a rotation of the roller 15 and thus the roller 17, whereby the rope 18 by the action of the tow link 19 pulls down a loop of the seat belt 20. At the same time as the line 18 is wound up on the roller 17, the belt roller 28 is automatically locked and remains locked in the same position because the belt 20 remains more or less tight around the driver's body 29 during the collision time, thereby tightening the already existing turns on the belt roller 28, and the seat belt is tightened the body of the restrained person, and this means that the otherwise common first collision between the body and the seat belt is absent. When the force from the first elemental charge 5 or the first elemental charges has subsided after a short time, the piston 2, due to the opposite tension in the line 13 (gravity of the body), will stop or perhaps return, at least for a short distance, before the next element charge detonates, whereby the repetitive movement of the piston 2 is stopped, or the piston 2 is pushed out a small distance once more. A small piece of the tow line 13 released after the previous detonation is then wound up again on the roller 15. In this way, the function continues during the entire collision process until the "programmed" serial charge 3 is completely burned out.

After the collision process, when there is no longer any force from the elementary charges, the piston 2, and thus also the retracted belt loop 20, will return to its normal, which is the position before the strong deceleration.

It is obvious that the function described above can also be achieved by mechanical, electrical, hydraulic, pneumatic or other means, although the described pyrotechnic function, due to its rapid and powerful reaction, is preferable. 463 406 / C Reference Figures il ÛQDÉQChUW-DOJRJI-l gl [nl | ¿| \> I * (JJ Il -b | _.a (n | _n G3 5.4 \ | ll æ ll KD I \ 1 @ VU ll I \ ') l' \) IV (n) N) -å IV U1 IV 05 H) \ l IV @ 29 cylinder ko1v serieïaddning cyïindertopp, koïvoppfångare eïementarladdning tändanordníng retardationssensor patronhyïsa bottenpïatta mutter evakueringshàï evakueringshâï dragïina dragïina dragïina dragïina dragïina dragïina ru11e (third) freewheel latch ru11e (fourth) omïänkare (fixed) omïänkare (fixed) håïlare bäïtesruïïe body NV:

Claims (9)

10 15 20 25 / I P a t e n t k r a v Procedure for force relief in the event of severe deceleration, such as in the event of a collision, in particular by persons strapped in vehicle or seat belts in vehicles, characterized in that the seat belt is stretched with a strong primary action but without being locked in such a stretch. position, by the fact that the seat belt after the first heavy stretch is given the opportunity to be relaxed a little, 'and by the fact that the seat belt is subsequently stretched and relaxed in controlled forms in a number of subsequent rapid series and with stretches which are smaller than the original stretch. Method according to claim 1, characterized in that the stretching of the seat belt takes place by actuating a pyrotechnic series charge containing a first strong element charge and a series of relatively weaker element charges, and in that the element charges are arranged to ignite successively one after the other with or without delay. Method according to claim 2, characterized in that the pyrotechnic serial charge is arranged to effect a stepwise relaxation and retraction of the seat belt after the primary sharp tightening of the seat belt, and after the detonation of the last elemental charge in the series to allow the seat belt to substantially regain its normal position, which is the position before the heavy detonation. Method according to claim 1, characterized in that the primary stretching takes place by a first strong impact followed by a series of further less severe influences without the seat belt being given the opportunity for any significant slackening, and that the seat belt is only then gradually stretched and slackened in a series of successive operations. 463 10 15 20 25 30 35 n; 406 Device for carrying out the method according to any one of the preceding claims for force relief in the event of severe decelerations such as in the event of collisions, in particular of persons fastened to vehicle or seat belts in vehicles, and consisting of a fixed cylinder (1), in which a piston ( 2) is displaceable under the influence of a pyrotechnic charge (3) arranged to be triggered by an ignition device (6, 7), and wherein the piston (2) is formed with a member such as a rope (13) or a rod (14) extending out of the cylinder (through 10) for connection to and direct actuation of the safety or protective means such as a seat belt (20) to be actuated, and where the pyrotechnic charge (3) consists of a series charge containing a plurality of elementary charges (5) arranged to detonate in succession until the entire series charge is burned out, characterized in that the piston (2) with the line (13) or the rod (14) is freely displaceable inside the cylinder, so that after detonating ion of each elemental charge (5) can move back inside the cylinder, allowing after each detonation a certain retraction of the seat or seat belt (20), in that the first elemental charge is of a relatively strong type, and that the following elemental charges is weaker or successively weaker, or that the strength of the elementary charges increases and / or decreases in a certain predetermined and desirable manner. Device according to claim 5, characterized in that the line (13) from the piston (2) in the pyrotechnic valve can cooperate with a device acting as a freewheel lock (21-24) which prevents a retraction of the retracted seat belt loop (20). to more than what corresponds to the unrolled length of the line (23) secured by the roll (24). ' Device according to claims 5 or 6, characterized in that the cylinder (1) is formed with a top or piston catcher (4) connected to the cylinder with holes (11) for evacuating air when the piston (2) is extended, and in that the cylinder (1) at a location between the serial charge (3) and the cylinder head (4) is formed with one or more evacuation holes (12), possibly with return valves, for discharging 10 l5 ”463 406 gas in excess from the detonations of the elementary charges. Device according to Claims 5, 6 or 7, characterized in that the tensioning device for the seat belt (20) consists of two fixed deflectors (25, 26) through which the seat belt extends, and an easily detachable and subsequently movable drawbar deflector (19), in which the line (13; 18) from the piston (2) is attached, and which upon detonation of the serial charge (3) causes a stretching of the seat belt by creating a double-weight loop in the seat belt. Device according to one of Claims 5 to 8, characterized in that the pyrotechnic serial charge is designed as a body of annular or helically arranged elementary charges or as a replaceable cartridge sleeve (8) which is clamped (through 10) in the bottom of the cylinder ( 1) or in a cavity in the displaceable piston (2), and having a through-going central hole for passing a towline (13) or the like for stretching a belt (20), and containing elementary charges of different strength and positioned in different positions relative to each other to provide a certain predetermined detonation force series and order.