Abstract:
As yet heads of belted passengers, when thrown forwards in real-world front collisions, crush into vehicle members or inflating airbags. 
     A safety device is equipped with wires, energy-absorbing, vibration-dampening delimiters, a collapsible upper portion of steering column and a pair of independently operating piston devices. The deflection of at least one piston rod in any front or rear collision is exploited to pre-tension the seat belts up to a predetermined length of seat-belt retraction and retract that collapsible upper portion with the steering wheel out of the head-injury area. 
     In order to prevent buckling of longitudinal runners, achieve the highest efficiency of energy-absorption and lower impact energy, to which passengers are exposed, a cone-shaped hub reams, folds and buckles the respective longitudinal runner, loosely guided by the piston rod, guided by a bearing box. 
     The delimiters block further movement of seat-belt wire thus preventing strangulation.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This is related to an international application number PCT/DE 98/00694 (WO 98/41422, German Patent DE 19711392 C1) filed Mar. 10, 1998. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     It is an object of the present invention to provide the front and/or rear section of vehicle body of motor vehicle with an energy-absorbing, vibration-dampening safety device
         to pull the steering wheel out of an area, in which the head, thrown forwards, smashes into it or is propelled backwards by an airbag;   to damp vibrations and lower pre-tensioning forces, imposed on belted passengers, in association with energy absorption and vibration-dampening,   to pre-tension the seat belts (safety belts) up to a predetermined length of seat-belt retraction and, when impact energy is great, to preserve the predetermined length of seat-belt retraction and to release pulling wires of the safety device
 
in any front or rear crash thus ensuring the survival chance either in co-operation with the front airbag or in case of a failure thereof or in operation with airbag.
       

     2. Description of the Related Art 
     It is known in the prior art to provide a motor vehicle with front airbags to softly cushion the head or a safety device to pre-tension the seat belts in co-operation with the airbags while pulling the steering wheel out of a head-injury area in order to avoid head injury. When the head-injury area is violated in a front crash, the upper part of the body of a front-seated or back-seated passenger belted, more particularly slackly belted or unbelted, is propelled forwards into the steering wheel, windshield, dashboard or backrest of the front seat. Recently, conventional safety devices fail to ensure survival chance in the following cases:
         When crashing into a MB E200 DT on a highway, a 42-year old driver of 5-month old BMW 5, which is strongly yaw-accelerated, suffers quadriplegia.   In a multi-crash of a 5-year old Ford Mondeo into a barrier and, finally, into a bus near the city of Idstein a 34-year old female driver submarines during which an inflating front airbag, fracturing her front face, forces it into her skull. Falsely deployed side airbags can injure passengers too!   In a crash of a 3.5-month old BMW 328i into another BMW the head of a 34-year old driver, thrown forwards, totally deforms the steering wheel.   The operation of airbags and sensors remains, to a surprising extent, unreliable, thus necessitating recall actions of 6,370 SAAB 9000s, 235,000 Volvo S70s, C70s and C70s, 150,000 MBs, 616,000 Opels, 16,500 VWs, 21,000 VWs, 280,000 BMW 3s, 900,000 AUDI 80s, A4s, A6s and A8s, 5,400 Porsche 911 Carreras and 911 Turbos and, recently, 116,000 Volvo S80s.   Ref. to pp. 178 in German Magazine “AUTO MOTOR und SPORT” issue 12/2002 researchers of Technical University in the city of Aachen found out that over 10% of airbag systems are defective. Within four years two millions of cars were already recalled due to defective airbag systems. Under these circumstances airbag systems pose to passengers a risk of injuries!
 
In order to pre-tension the seat belts, operated by a belt pulley driven by an engine, the members of a release device ref. to DE 3536393 A1 are force-locking connected with each other by a wire (pp. 6/col. 37 to 43), which is activated in the event of deformation of a vehicle member. With the data n=6000 U/min, radius of belt pulley=10 mm and t=20 ms lower than the deployment time of BMW-Frontairbag by 22 ms the formula of seat belt-tension yields a retraction of 20 mm, which is less due to the slip-coefficient of the belt webbing on the belt pulley and due to its elongation and can never meet the requirement for retraction of from 300 to 350 mm.
 
In order to prevent fire the engine is put out of operation by interrupting the gasoline-supply and/or electric circuit. The release device remains ineffective at all.
       

     Ref. to WO 90/14253 a front bumper consists of a first part, whereto a first row of rollers is transversely attached, a second part, whereto a second row of rollers is transversely attached, and a first strip member, arranged between both rows of rollers. Both ends of the first strip member are rigidly attached to a pair of movable rollers, about which a second strip member is wounded. Both ends of the second strip member, rigidly attached to seat belts of passengers. In a mid-front crash the deflection of the first rollers between the second rollers causes a lateral movement of both movable rollers in opposite direction during which the second strip member tightens both seat belts to a limited extent. In offset-crashes it does not work. 
     Despite voluminous form the front bumper is unsuited to absorb small energy when colliding into a barrier during parking. The damage on the device as well as on the front section of the vehicle incurs high repair costs. 
     Ref. to DE 4106480 A1 a clamping device consists of a front tube, fastened to a longitudinal runner, and a rear guide tube, which is fastened to the longitudinal runner and the front portion of which is loosely guided by the front tube, to loosely guide a wire. Under the premise, that the distance between both tubes is shorter, when the front portion is deformed, the wire pre-tensions seat belts of passengers. In real-world front crashes the device is fouled when
         the portion of the longitudinal runner together with the device collapses or   the front portion with the device is not deformed while the front portion of the other longitudinal runner without device is deformed.       

     Ref. to EP 0234003 A1 a safety device, designed for a vehicle having mid- or rear-engine, has a pair of longitudinal rods, located in a pair of longitudinal runners, one ends of which and the other ends are fastened to the front portions of both longitudinal runners and to two first wires, which are connected to an intermediate wire in connection with two second wires, connected to the belt retractors. In a mid-front crash the deflection of both front portions of the longitudinal rods causes an elongation of both first wires, which are outwardly deflected upon the contact with guide plates of the longitudinal runners. As a result, both second wires activate the belt retractors to pre-tension the seat belts. Due to lack of vibration-dampening energy absorbers and delimiters the passengers are exposed to large acceleration of those rods, strangulation linked to unlimited deflection and whiplash-related oscillations. 
     Ref. to DE 3627558 C1 three wires of a safety device, activated by an intrusion of the power plant in a mid-front crash, pull the steering wheel out of the head-injury area and pre-tension all seat belts. Unfortunately, the passengers are subjected to severe/fatal injuries resulting from
         large acceleration, strangulation and whiplash-related oscillations in real-world mid-front crashes or   failure of the safety device in real-world offset front crashes.       

     The deficiencies of the features of DE-OS 1655597, DE 3536393 A1, DE 3736949 A1, DE 4106480 A1, WO 85/01709 and WO 90/14253, respectively, are similar to that of EP 0234003 A1 and DE 3627558 C1 
     In order to resolve the above-mentioned deficiencies of EP 0234003 A1, DE 3627558 C1, WO 85/01709 A1 and DE 3736949 A1 the proprietor AUDI Corp. has invented a safety device, disclosed in DE 3801347 C2, under a trademark “procon-ten”, an abbreviation for programmed contraction-tension, shown in  FIG. 5 . In a mid-front crash a rod  201  of the power plant  10  pulls
         a wire  208 , which pre-tensions via pivots  204 ,  205 ,  206  seat belts  64  of all passengers in “SG”-direction and   a wire  209 , which pulls via two pivots  204 ,  205  a steering wheel  90  out of the head-injury area in “S L ”-direction during which a collapsible casing 91.1 of the steering column  91 , fastened to a dash panel of the passenger compartment, is compressed.
 
Unfortunately, the safety device “procon-ten” incurs a series of drawbacks such as:
       

     For years R&amp;D work has been focused on
         developing compact as well subcompact cars suitable for daily driving to workplace, meeting with customers, resolving the problems of increasing traffic congestion, easily finding a parking lot and lowering the fuel consumption to under 4 1/100km and   improving the passenger protection to pass increasingly strict EU and US-crash tests.
 
A compact car, such as MB (Mercedes Benz) A-Class® with 3.58×1.56×1.72 m, has an extremely short front section, for which the device “procon-ten” is unsuited. In order to enhance survival chance and the energy-absorbing property of longitudinal runners in a mid-front crash the power plant  10 , sliding down along the stiff sliding surface (scuttle)  55 , is displaced from the engine compartment to underneath the passenger compartment while rear bearings  22 , serving as sites of predetermined fracture, are broken, as exemplified in U.S. Pat. No. 5,492,193 and shown in  FIGS. 2 and 3 . In an offset front crash or in a major mid-front crash this embodiment fails due to fouling the condition that both rear bearings must be broken simultaneously. This and other shortcomings are resolved by features of separation of the power-plant from the front section of the vehicle body and/or by enhanced energy absorption of longitudinal runners in front- or rear crashes, disclosed in DE 19636167 C1, CA 2,236,816 and US-pending patent.
       

     An Institute of Vehicle Safety, a Department of GDV (Association of German Insurers), in Munich has conducted a research on front crashes, classified into four front crash types one of which, the mid-front crash type, shows a low percentage just 19.3% regarding fatal injuries. 
     The upper part of body as well as the head are subjected to strong oscillation due to lack of undamped vibration in a front- or rear crash. In the crash tests, carried out by the Institute of Vehicle Safety in co-operation with Technical University in Graz, Austria, to idealize a real-world rear crash, the torso is propelled out of the seat backrest after a lapse of 40 ms (milliseconds) while the initial position of the head remains unchanged. After a lapse of 100 ms the head is accelerated backwards. After a lapse of 130 ms the head comes into contact with the head rest. The pitch acceleration reaches the maximum. A rebound (repetition of forward motion) of the upper part of body occurs within 200 ms. Despite low speed at 8.5 km/h and low acceleration at 2.5 g in the crash tests of nine different vehicle seats the upper part of body always oscillates. One out of 22 volunteers suffers minor cervical injury, lasting for two days, and a few minor pain, lasting for one to two days. 
     Due to poor energy-absorption of the rod  201  of the power-plant, far less than that of both deformable longitudinal runners having a peak acceleration of 60 m/s 2 , disclosed in DE 3826958 A1, and due to great remaining impact energy, when crashing at high speeds into the very stiff column of a highway, the power plant intrudes into the passenger compartment and the seat belts, strongly pulled by the wire  208 , strangulate all restrained passengers, particularly, a fetus of pregnant female passenger. 
     The rod  201  has to carry out five operations to limit the backward movement of the power plant, to absorb impact energy, to serve as the third bearing of the power plant, to adjust the wire and to convert the movement of the power plant into a movement of both wires. The failure of the device is due to the controversy of the different operations. 
     Ref. to DE 4224489 A1, whose features are found in AUDI A8 as well as A2, and DE 3826958 A1 a deformable longitudinal runner with a length of “L E ”, shown in  FIG. 10 , is subdivided into “n+1” longitudinal members “Z 1 , Z 2 , . . . , Z a , . . . , Z b , . . . , Z c , . . . , Z d , . . . , Z n , Z n+1 ”. The longitudinal member “Z n+1 ”, having the largest stiffness, is the rear portion of the longitudinal runner, facing the passenger compartment. 
     Furthermore, DE 19615985 C1 (CA 2,249,667) and DE 19636167 C1 (CA 2,236,816 and US-pending patent) teach the stiffness of the longitudinal runner can be increased by additional elements integrating therein. Controllable deformation behaviour is accomplished by unequal stiffness of juxtaposed longitudinal members, under load, having different peak stresses. However, they may have peak stresses at the same level as long as their longitudinal members, for example, “Z 2 ” and “Z 10 ” are not in juxtaposition. The transient times to the yield value (fracture stress) are variable, hence, determinable. To resolve the problem of buckling of conventional longitudinal runner under great load and to achieve the highest efficiency of the energy absorption the deformable longitudinal runner, guided by the piston rod, is controllably folded, buckled and reamed by a cone- or torus-shaped hub  5 . 3  of piston head  5 . 1   a , shown in  FIG. 6 . 
     SUMMARY OF THE INVENTION 
     Accordingly, the principle object of the present invention is to provide for a motor vehicle a safety device, comprising a pair of independently operating piston devices, arranged in the front and/or rear section of vehicle body, wires, pivots (pivotal rollers), and vibration-dampening, energy-absorbing delimiters in order to pre-tension the seat belts of all passengers and absorb the pre-tensioning forces to a predetermined length of seat-belt retraction, lower the belt forces, resulting from mass forces of the forward motion movement of the belted passengers, dampen whiplash-related oscillations of the belted passengers and pull the steering wheel out of a head-injury area in real-world front or rear crashes. 
     A second object of the present invention resides in the independently operating piston device having a cone- or torus-shaped hub which folds, buckles and reams the deformable longitudinal runner, being loosely guided by the piston rod, in order to gradually absorb impact energy and to achieve the highest efficiency of the energy absorption. 
     A third object of the present invention resides in a cost-, space-saving construction of different safety devices, each of which, provided with means to compensate manufacturing and assembly tolerances, can be installed in any motor vehicle, as exemplified in the compact car MB A, shown in  FIGS. 2 and 3 . A car manufacturer, having many vehicle classes (models) on the sales program, can equip them with one to two safety devices, whose wires  60 ,  61 ,  62  have a few different wire lengths and whose piston rods  5   a  to  5   d  have a few different wire lengths. In compliance with cost-, space-saving arrangement the following pair of piston rods  5 ,  5   a  to  5   d ,  5   c   1  can be arranged in the front and rear section of vehicle body of several vehicle models pursuant to the claims  1  to  3  and  26  to  28 :
         Ref. to  FIGS. 1 ,  6  and  11  a wire-guiding member  52 , to accommodate a wire and a delimiter and deform an additional energy absorber  1 , is fastened to the rear portion of each piston rod  5 , which is arranged in the longitudinal runner  30  and guided by a bearing box  30 . 7 ,  30 . 7   a , rigidly attached to that and/or to the torque box  31 .   Ref. to  FIGS. 2 and 4  the front portion of each piston rod  5   c , arranged sideward to the longitudinal runner  30 , is bolted to the front portion of longitudinal runner  30 , the mid-portion is loosely guided by a bearing  58   c  of reinforced dash panel  55  and a guide sleeve (member)  52   a , to accommodate two wires, is fastened to the rear portion.   Ref. to  FIGS. 3 ,  3   a  and  4  the front portion of each piston rod  5   c   1 , arranged sideward to the longitudinal runner  30 , is bolted to the front portion of longitudinal runner  30 , the mid-portion is loosely guided by a bearing  58   c   1  of torque box  31  and a guide sleeve  52   a , to accommodate two wires, is fastened to the rear portion.   Ref. to  FIG. 7  the front portion of each piston rod  5   d , arranged lower to the longitudinal runner  30 , is bolted to the front portion of longitudinal runner  30 , the mid-portion is loosely guided by a bearing  58   d  of torque box  31  and a guide sleeve  52   a , to accommodate two wires, is fastened to the rear portion.   Ref. to  FIG. 9  the front portion of each piston rod  5   a , arranged upper to the longitudinal runner  30 , is bolted to the front portion of longitudinal runner  30 , the mid-portion is loosely guided by a bearing  58   a  of torque box  31  and a guide sleeve  52   a , to accommodate two wires, is fastened to the rear portion.   Ref. to  FIG. 10  the front portion of each piston rod  5   b , arranged in the longitudinal runner  30 , is bolted to the front portion of longitudinal runner  30 , the mid-portion is loosely guided by a bearing  58   b , which is a hole in the torque box  31 , and a guide sleeve  52   a , to accommodate two wires, is fastened to the rear portion.
 
Shown in  FIG. 3   a , the bearing  58   a  to  58   d ,  58   c   1  is provided with a soundproofing bush  58 . 1  to isolate noise and enhance the movement of the piston rod therein when being displaced together with the longitudinal runner  30 . Accordingly, piston rods  5   c ,  5   c   1 ,  5   d ,  5   b  are provided with soundproofing bushes, like  54 . 1 , shown in  FIG. 9 , at the respective attachment points. To save assembly time the hole of piston rod  5   b  is pre-assembled with rubber sleeve (not drawn).
 
The profile of piston rods  5   a  to  5   d ,  5   c   1 ,  5   e   1  to  5   e   4  is arbitrary, however preferably, round or square due to low manufacturing costs.
 
Usually, manufacturing tolerances and indeterminate (large) assembly tolerances result in a play which must be compensated by repositioning the wire to the piston rod, to the delimiter and/or to the clamping member of the delimiter and/or the piston rod to the longitudinal runner. This requirement for an appropriate position of the wire is met by distributing the following adjusting holes along the following members of the safety device:
   adjusting holes “H 1 , H 2 , . . . , H n ”, along piston rod  5   d  ( FIG. 7 ),   adjusting holes “K 1 , K 2 , . . . , K n ” along piston rod  5   a ,  5   b ,  5   d  ( FIGS. 7 ,  9 ,  10 ),   adjusting holes “L 1 , L 2 , . . . , L n ” and “N 1 , N 2 , . . . , N n ” along energy-absorbing steering-column delimiter  51  with site of predetermined fracture “b” ( FIG. 11 ),   adjusting holes “N 1 , N 2 , . . . , N n ” along energy-absorbing steering-column delimiter  51   a ,  51   c ,  51   d ,  51   e  with site of predetermined fracture “b” ( FIGS. 8 ,  9  and  19  to  21 ) and/or   adjusting holes “M 1 , M 2 , . . . , M n ” along tube  71 . 1  or clamping member  82 ,  82   a ,  82   b  ( FIGS. 12 to 16 ).
 
Alternatively, a spacer  60 . 6  with open profile and length of “g 1 ” is clamped onto a pre-wire  60 . 1   e , preferably, in front of the blocking ring  60 . 7  to correct the distance of “g” between the blocking ring  60 . 7  and support plate  60 . 8 , fixed to the side rail  34 , shown in  FIG. 21 . The process of clamping is illustrated by an arrow. The adjusting work can be done elsewhere upon allocation of a number of spacers  60 . 6  with different lengths “g 1 , g 2 , . . . , g m , g n ” (not shown).
 
In a time-, cost-saving decision an assembly worker at assembly line can compensate a play by occupying, for example, an appropriate hole “L 3 ” ( FIG. 11 ) for fastener  51 . 2  of energy-absorbing steering-column delimiter  51  instead of the designed hole “L 1 ” and/or by clamping a spacer  60 . 6  with open profile and length of “g 1 ” to the pre-wire of wire  61 ,  62 .
       

     A fourth object of the present invention facilitates the safety device to co-operate with a separation of the power plant ref. to DE 19636167 C1 (CA 2,236,816 and US-pending patent) and with additional energy absorbers ref. to DE 19615985 C1 (CA 2,249,667), such as energy absorbers  1 , shown in  FIGS. 1 ,  6  and  11 , in order ensure and enhance survival chance and, in particular, resolve the crash incompatibility issue, in which a light car, for example, a subcompact or compact car, is front-end hit by a utility vehicle, for example, a pickup, truck or SUV. As reported in IIHS Vol. 34, No. 9, Oct. 30, 1999, two-vehicle collisions between cars and utility vehicles in USA account for about 15 percent of all car occupant deaths. 
     In surmounting the foregoing shortcomings of conventional safety devices and, in particular, the failure in offset front crashes or major accidents all the objects ensure the operation of the safety device as well as survival chance in real-world front or rear crashes, illustrated in  FIGS. 1 to 3  and  6  to  10 , where
         in an offset front or rear crash, when “F&gt;F”, the piston rod  5  moves (backwards) along the y2x-axis or, when “F&gt;F”, the other piston rod  5  moves along the y2-axis, or   in a mid-front or mid-rear crash, when “F=F”, both piston rods  5  move along the y2- and y2-axis.
 
During which impact energy is absorbed by at least one longitudinal runner  30  and by at least two pairs of vibration-dampening, energy-absorbing delimiters  70 ,  80 ,  80   a  to  80   e  with site of predetermined fracture “b”, shown in  FIGS. 12 to 21 , and, optionally, by at least one deformable element  1 , shown in  FIGS. 1 to 6 .
 
Obviously, the operation to pre-tension seat belts in direction “S 0 ” has to be separated from that to retract the steering wheel out of the head-injury area independent of direction “S 1 ” and “S 2 ”. The retraction must be limited by at least one energy-absorbing steering-column delimiter  51 ,  51   a  with site of predetermined fracture “b” ( FIGS. 8 ,  9  and  11 ). Both features are extended by the following features. Each vibration-dampening, energy-absorbing delimiter  70 ,  80 ,  80   a  to  80   e , shown in  FIGS. 1 ,  12  to  21 , has a multi-purpose:
   to perform work of deformation and of friction, thus absorbing (dissipate) impact energy, lowering the pre-tensioning force of seat belts, by fracturing the sites of predetermined fracture “b” in excess of a predetermined value, and damping whiplash-related oscillations, to which the heads are exposed,   to limit (restrict) the retraction-length of seat belts in order to prevent strangulation and   to preserve lengths of retracted seat belts and the clamping force of the clamping member on the retaining member by way of engagement of retaining assembly, consisting of
           retaining notch of tube  71 . 1  and retaining plate  71 . 3 , pivotally attached to both plates  71 . 4  and biased by spring  71 . 5 , shown in  FIG. 12 , or   a pair of retaining apertures of expanding clamping member  82   a  and two-side retaining strut  81 . 2   a  of retaining member  81   a , shown in  FIGS. 14 and 15 , or   a retaining collar  82 . 1   b  of contracting clamping member  82   b  and retaining notch of retaining member  81   b , shown in  FIGS. 16 to 18 .
 
Clamping (spring) force of the clamping member on the retaining member depends on the material, length, denoted by “ 1 ”, longitudinally variable width of gap, denoted by “s”, shape of the delimiter itself and spring rate of the clamping member, which expands or contracts, during its forced movement along the cone-shaped portion of the retaining member. Applying the same parameters on the design of the delimiter and the cone-shaped portion of the retaining member, the clamping force of the clamping cylinder-shaped member  82  with diameter of “d 0 ” is less than that of the clamping cone-shaped member  82   a . For the purpose of ideal contact with each other the portion  81 . 3   a  to  81 . 3   e  of retaining member  81   a  to  81   e  and clamping member  82   a  to  82   e  have the same conical shape, determined by the formula “(D 2 −D 1 )/L=(d 2 −d 1 )/1”, shown in  FIGS. 14 to 21 . Owing to these features
   
           the expansion or contraction of the clamping member increases the clamping force and   work of deformation and of friction is accomplished when the clamping member, whose gap is loosely guided by the part of the mating retaining member, moves along the retaining member.
 
Due to longitudinally contracting the circumference of clamping member with diameter “D 2 ” and “D 1 ” to an amount of, for example, 0.5 mm the clamping force of the delimiter  80   a ,  80   c  is increased accordingly.
 
Each delimiter  80 ,  80   a  to  80   e  under load of pre-clamping force can be pre-assembled by
   expanding the clamping member  82 ,  82   a ,  82   c  with gap, arranged on the retaining member  81 ,  81   a ,  81   c , or   contracting the clamping member  82   b ,  82   d  with gap, arranged in the retaining member  81   b ,  81   d.  
 
Owing to big friction coefficient, large contact area of clamping member with retaining member and wide expansion or contraction the clamping force is strong enough to pre-tension and retain the seat belts. A test can determine whether the cheapest delimiter  80   e  without retaining and blocking parts, shown in  FIG. 21 , works. It consists of
   a retaining member  81   e  representing any one of members  81 ,  81   a  to  81   d  and   a clamping member  82   e  representing any one of members  82 ,  82   a  to  82   d  without retaining and blocking parts, however, with alien-blocking parts  60 . 6  to  60 . 8 .
 
To avoid noises the cone-shaped portion of retaining member  81 ,  81   a  to  81   e  is surrounded by a soundproofing material  83 , shown in  FIG. 15 . The work of friction depends on clamping force, surface property of both members on contact and friction coefficient. The work of deformation, friction is achieved during the deformation of clamping member, pulled by the wire  60 , moved along the retaining member, similar to spring  72  and shock absorber  73 .
       

    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A number of embodiments, other advantages and features of the present invention will be described in the accompanying drawings with reference to the xyz global coordinate system: 
         FIG. 1  is a schematic view of a vehicle frame, a power plant  10 , steering wheel  90 , steering column  91  and a pair of deformable elements  1 , loosely guided by wire-guiding members  52 , and a 1st embodiment of the safety device, having a pair of independently operating piston rods  5  with piston heads  5 . 1 , guided by bearing boxes  30 . 7 , which are arranged to a pair of longitudinal runners and/or a torque box  31 , wires  60  to  62 , energy-absorbing steering-column delimiters  51 , pivots  40  to  49  and a 1 st embodiment of two pairs of energy-absorbing, vibration-dampening delimiters  70  in xy-plane. 
         FIGS. 2 and 3  illustrate a longitudinal cross section of a transversally-built power plant of MB A being displaced ref. to U.S. Pat. No. 5,492,193 and a 3rd and a 4th embodiment of the safety device in a mid-front crash. 
         FIG. 3   a  is a partially enlarged cross-sectional view of a bearing  58   c  with a soundproofing bush  58 . 1  to guide each piston rod  5   c   1  of the safety device, shown in  FIG. 3 . 
         FIG. 4  is a perspective view of the longitudinal runner  30 , whose longitudinal member “Z c ”, reinforced by an additional element  3   c , accommodates the front portion of the piston rod, shown in  FIGS. 2 and 3 . 
         FIG. 5  is a perspective view of an AUDI safety device “procon-ten” ref. to DE 3801347 C2. 
         FIG. 6  is a schematic view of a vehicle frame, a power plant  10  and a pair of deformable elements  1 , loosely guided by wire-guiding members  52 , and a 2nd embodiment of the safety device, having a pair of independently operating piston rods  5  with cone- or torus-shaped hubs  5 . 3  and piston heads  5 . 1   a , guided by bearing boxes  30 . 7   a , arranged to a pair of longitudinal runners and/or a torque box  31 , and delimiters. 
         FIG. 7  is a perspective view of a longitudinal runner  30 , whose longitudinal member “Z d ”, reinforced by an additional element  3   d , accommodates a piston rod  5   d  of a 5th embodiment of the safety device. 
         FIG. 8  is a cross-sectional view of a 6th embodiment of the safety device, along the line II—II of  FIG. 9 , having an energy-absorbing steering-column delimiter  51   a  and a spacer  51 . 6   a  with open profile and length of “f 1 ” which is in process to be clamped onto a wire  61  to correct the distance of “f” between the blocking ring  51 . 4   a  and support plate  51 . 5   a.    
         FIG. 9  is a schematic perspective view of a half of the 6th embodiment of the safety device with piston rod  5   a , wires  60 ,  61 , guide sleeve  52   a , pivots  44   a ,  47   a ,  48  and the energy-absorbing steering-column delimiter  51   a.    
         FIG. 10  is a schematic perspective view of the longitudinal runner  30 , subdivided into “n+1” longitudinal members one “Z b ” of which is reinforced by an additional element  3   b  to accommodate a piston rod  5   b  of a 7th embodiment of the safety device. 
         FIG. 11  is a cross-sectional view of the 1st embodiment of the safety device and the energy-absorbing delimiter  51  along the line I—I of  FIG. 1 . 
         FIG. 12  is a schematic perspective view of the delimiter  70  having a delimiting unit  71 . 
         FIG. 13  is a schematic perspective view of a 2nd embodiment of the energy-absorbing, vibration-dampening delimiter  80 . 
         FIG. 14  is a schematic perspective view of a 3rd embodiment of the energy-absorbing, vibration-dampening delimiter  80   a.    
         FIG. 15  is a cross-sectional view of a clamping member  82   a  of the delimiter  80   a  whose movement, guided by a longitudinal strut  81 . 1   a  of retaining member  81   a  and/or a retaining strut  81 . 2   a , is blocked by a pair of retaining apertures in engagement with the retaining strut  81 . 2   a  along the line III—III of  FIG. 14 . 
         FIG. 16  is a schematic perspective view of a 4th embodiment of the energy-absorbing, vibration-dampening delimiter  80   b.    
         FIGS. 17 and 18  illustrate a cross-sectional view of a clamping member  82   b  of the delimiter  80   b  whose movement, guided by a guide pin  82 . 2   b , is blocked by a retaining collar  82 . 1   b  in engagement with a retaining notch of retaining member  81   b  along the line IV—IV of  FIG. 16 . 
         FIG. 19  is a schematic perspective view of a 5th embodiment of the energy-absorbing, vibration-dampening delimiter  80   c.    
         FIG. 20  is a schematic perspective view of a 6th embodiment of the energy-absorbing, vibration-dampening delimiter  80   d.    
         FIG. 21  is a schematic perspective view of a 7th embodiment of the energy-absorbing, vibration-dampening delimiter  80   e.    
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The right-hand drive vehicle is represented by the steering wheel  90 , shown in  FIGS. 1 and 5 . However, all features are suited for right-hand drive vehicles as well as for left-hand drive vehicles. 
     The 2nd embodiment of the safety device, shown in  FIG. 6 , differs from the 1st embodiment, shown in  FIG. 1 , in the piston rods  5 . 1   a , provided with cone- or torus-shaped hubs  5 . 3  which avoid an extremely outward deflection of longitudinal runners during deforming, reaming and folding the longitudinal members in longitudinal direction to substantially dissipate great impact energy. 
     The end portion of each piston rod  5 , guided by bearing box  30 . 7 ,  30 . 7   a , is fastened to a wire-guiding member  52  of deformable element  1 , shown in  FIGS. 1 ,  6  and  11 , which has a web with a hole, serving as pivot  47  to pivotally move and deflect the wire  60 . The wire  60 , further wound about the pivots  48 ,  49 , has both ends, attached to at least one pair of delimiters  70 ,  80 ,  80   a  to  80   e  in connection with all seat belts of the motor vehicle.
 
Each wire-guiding member  52  accommodates an energy-absorbing steering-column delimiter  51 , one of the adjusting holes of which is occupied by one end of wire  61 ,  62 . Onto the other ends wire holders  61 . 1 ,  61 . 2  are clamped. Both wires are wound about the respective pivots  42 ,  43  and  45 ,  46 . Threaded stud  41 . 1 , accommodating both wire holders, has a threaded end projection onto which a nut  41 . 2  is screwed to secure them.
 
Upon large deflection of wire-guiding member  52  in an offset front crash the seat belts  64  of belted passengers are pre-tensioned up to a predetermined length of seat-belt retraction, vibration is dampened, energy is absorbed by deforming the longitudinal runner  30 , deformable element  1  and the delimiters  70 ,  80 ,  80   a  to  80   e ,  51 ,  51   a  and the movement of blocking pin  51 . 4  is blocked by support plate  51 . 5  thus ending up in fracture of site of predetermined fracture “b” and in further pulling of the steering wheel  90  until it comes into contact with the dashboard. As a result, the site of predetermined fracture “b” of the energy-absorbing steering-column delimiter  51   a  ( FIG. 8 ) is broken and the wire  61 ,  62  is released. Alternatively, only one single pair of energy-absorbing steering-column delimiters  51  is used. In that case the site of predetermined fracture “b” has to be redesigned between the hole “L 1 ” and the wire-guiding member  52  ( FIG. 11 ). Car Corps. have an option for a single or multi-energy absorption.
 
Due to great impact energy the wire  60  is released too and the predetermined length of seat-belt retraction and the clamping force are conserved, as outlined hereinafter.
 
     In the 1st embodiment the delimiter  70 , shown in  FIGS. 1 and 12 , comprises a spring  72 , shock absorber  73  and a delimiting unit  71 , consisting of a tube  71 . 1  and support member  71 . 2  with plate  71 . 3 , which, biased by spring  71 . 5 , comes in engagement with a notch of the tube, being moved by tension force of wire  60 , to limit the retraction-length of seat belts. The non-recurring delimiter  70  is too expensive. Car Corps. are interested more in cost-, space saving embodiments, which are described hereinafter: 
     In the 3rd to 7th embodiments of the safety devices without costly bearing boxes  30 . 7 ,  30 . 7   a , shown in  FIGS. 2 ,  3 ,  7 ,  9  and  10 , a pair of piston rods  5   a  to  5   d ,  5   c   1  is arranged in or to the longitudinal runners  30 . The piston rod provided with bush such as  54 . 1  is in force-locking connection with the reinforced longitudinal member by way of riveting or welding or a fastener, consisting of bolt  54  and nut  54 . 2 , shown in  FIG. 9 . Costs are further saved by multi-use of the fastener  52 . 1  to fasten the wire holder  61 . 1   a  of wire  61  to guide sleeve  52   a , shown in  FIGS. 9 and 10 , and the guide sleeve  52   a  to piston rod  5   a ,  5   b  as well as by multi-use of the guide sleeve  52   a  to retain those wires and to pivotally move and deflect the wire  60 . 
     Each retaining member of energy-absorbing, vibration-dampening delimiter  70 ,  80 ,  80   a  to  80   e , shown in  FIGS. 1 ,  12  to  21 , has attachment points for the purpose of force-locking connection with any stiff motor-vehicle member like side rail  34 , shown in  FIG. 21 .
 
Each member  71 . 1 ,  82 ,  82   a  to  82   c , movable by tension force of wire  60 , is provided with site of predetermined fracture “b” to limit the retraction-length of seat belts. Alternatively, the delimiters  80   d ,  80   e  in co-operation with delimiters  51   a  to  51   e , each having site of predetermined fracture “b”, are put into use.
 
     In the 2nd and 3rd embodiment the delimiter  80 ,  80   a , shown in  FIGS. 13 to 15 , comprises an expanding clamping member  82 ,  82   a  and a retaining member  81 ,  81   a . The work of deformation and friction is increased when the mating members, being in contact with each other, are cone-shaped. A gap, denoted by “s”, has influence on the spring rate or clamping force and the engagement of both members with each other. Owing to the guide assembly, consisting of the gap and the strut  81 . 1 ,  81 . 1   a , the clamping member  82 ,  82   a , loosely guided by the strut, moves along the retaining member  81 ,  81   a . To maximize the clamping force of clamping member  82   a  moving along the retaining member  81   a , a longitudinal gap “S A ” (not drawn) must be defined by the magnitude of longitudinal gap “s a &gt;0” which may neither be too small nor too big between the gap and strut  81 . 1   a  as well as between the gap and two-side retaining strut  81 . 2   a  in longitudinal direction. After projection through holes of clamping member  82   a  and fork-shaped wire holder  60 . 2  of belt wire  60 . 1  of seat belts  64 , the blocking pin  60 . 3  is secured by two securing parts  60 . 4 . After engagement of the retaining assembly, consisting of a pair of apertures and the two-side retaining strut, further movement of the clamping member  82   a  is blocked upon the contact of blocking pin  60 . 3  with the surface of retaining member  81   a  because its clearance of “S 2 ” is smaller than the clearance of “s 1 ” ( FIG. 15 ). Site of predetermined fracture “b” is fractured by great impact energy to prevent strangulation of belted passengers and to limit the pre-tensioning force. 
     In the 4th embodiment the delimiter  80   b , shown in  FIGS. 16 to 18 , comprises a contracting clamping member  82   b  and a retaining member  81   b . After projection through holes of clamping member  82   b , wire holder  60 . 2   a  of belt wire  60 . 1  and a pair of guide sleeves  60 . 5   a , end projections of the blocking pin  60 . 3   a  are secured by two securing parts  60 . 4   a.    
     Owing to a guide assembly, consisting of a guide pin  82 . 2   b  and a gap, the clamping member  82   b , loosely guided by the guide pin, moves along the retaining member  81   b . To maximize the clamping force of clamping member  82   b  moving along the retaining member  81   b , a longitudinal gap “S B ” (not drawn) must be defined by the magnitude of longitudinal gap “S b  &gt;0” which may neither be too small nor too big between the gap and guide pin  82 . 2   b  in longitudinal direction.
 
A cone-shaped chamfer, denoted by “a”, assists the process of engagement of a retaining assembly, consisting of retaining collar  82 . 1   b  of clamping member  82   b  and a retaining notch of retaining member  81   b . After the engagement of retaining collar  82 . 1   b  with the retaining notch within a clearance of “S 3 ”, further movement of the clamping member  82   b  is blocked upon the contact of the pair of guide sleeves  60 . 5   a  of blocking pin  60 . 3   a  with a pair of open notches of retaining member ( FIGS. 17 and 18 ). Site of predetermined fracture “b” is fractured by great impact energy to prevent strangulation of belted passengers and to limit the pre-tensioning force.
 
     In the 5th embodiment the delimiter  80   c , shown in  FIG. 19 , comprises an expanding clamping member  82   c  without site of predetermined fracture, a retaining member  81   c , retaining assembly, consisting of a pair of retaining apertures and two-side retaining strut  81 . 2   c  of strut  81 . 1   c , and delimiter  51   c  with site of predetermined fracture “b”. After projection through holes of clamping member  82   c , fork-shaped wire holder  60 . 2   c  of pre-wire  60 . 1   c  and two guide sleeves  60 . 5   a , the blocking pin  60 . 3   c  (similar to  60 . 3 , hence not drawn) is secured by two securing parts  60 . 4   a . The process to preserve the clamping force is similar to that of the 3rd embodiment. 
     In the 6th embodiment the delimiter  80   d , shown in  FIG. 20 , comprises a contracting clamping member  82   d  without site of predetermined fracture, a retaining member  81   d , retaining assembly, consisting of a retaining notch and retaining collar  82 . 1   d  of clamping member  82   d , and delimiter  51   d  with site of predetermined fracture “b”. After projection through holes of clamping member  82   d , fork-shaped wire holder  60 . 2   d  of pre-wire  60 . 1   d  and two guide sleeves  60 . 5   a , the blocking pin  60 . 3   d  (not drawn, similar to  60 . 3 ) is secured by two securing parts  60 . 4   a . The process to preserve the clamping force is similar to that of the 4th embodiment. 
     In the 7th embodiment the most economical delimiter  80   e  without retaining and blocking parts, shown in  FIG. 21 , comprises an expanding or contracting clamping member  82   e  without site of predetermined fracture, a retaining member  81   e  and delimiter  51   e  with site of predetermined fracture “b”. 
     As above-mentioned, the distance between blocking ring  60 . 7  and support plate  60 . 8  is adjusted by spacer  60 . 6  and the process to preserve the clamping force is similar to that of the previous embodiments. 
     In order to formulate in single terminology for Claims a generalized definition for the proper term is presented: 
     
       
         
               
               
               
             
           
               
                   
                   
               
               
                   
                 Definition: 
                 Proper Term: 
               
               
                   
                   
               
             
             
               
                   
                 “guide assembly” 
                 guiding member (81.1, 81.1a, 82.2b) 
               
               
                   
                   
                 &amp; guided member, such as gap etc. 
               
               
                   
                 “retaining assembly” 
                 key (81.2a, 82.1b) &amp; receptacle, 
               
               
                   
                   
                 such as a pair of retaining 
               
               
                   
                   
                 apertures, retaining notch etc. 
               
               
                   
                 “blocking assembly” 
                 blocking member (60.3, 60.3a) &amp; 
               
               
                   
                   
                 contacted member, such 
               
               
                   
                   
                 as surface of retaining member, 
               
               
                   
                   
                 a pair of open notches etc. 
               
               
                   
                   
               
             
          
         
       
     
     Although the present invention has been described and illustrated in detail, it is clearly understood that the terminology used is intended to describe rather than limit. Many more objects, embodiments, features and variations of the present invention are possible in light of the above-mentioned teachings. Therefore, within the spirit and scope of the appended claims, the present invention may be practised otherwise than as specifically described and illustrated.