WO1997047496A1

WO1997047496A1 - Arrangement in a bumper

Info

Publication number: WO1997047496A1
Application number: PCT/NO1997/000151
Authority: WO
Inventors: Roald H. Pedersen; Rolf Vold
Original assignee: Hydro Raufoss Automotive As
Priority date: 1996-06-10
Filing date: 1997-06-10
Publication date: 1997-12-18
Also published as: DE19781796T1; NO962433L; NO962433D0

Abstract

The present invention relates to an arrangement in a structure member, especially a structural beam and more specifically a bumper bar (1) for a vehicle or vessel, and in order to provide a relatively rapid and inexpensive system, which has a short reaction time and which is easy to reset, it is according to the invention suggested that said arrangement comprises means for displacing said bar (1) in relation to the vehicle, for thereby, especially in an emergency situation, to elongate respectively expand the deformation zones of said vehicle whilst simultaneously enabling bar locking means (7; 107) to be effective.

Description

Arrangement in a bumper

Field of the invention

The present invention relates to an arrangement in a structural member, especially a structural beam and more specifically a bumper bar for a vehicle or vessel.

Prior art From GB 414,586 (Porsche) there is previously known a bumper bar supported by two shock absorber units, each including a piston with fluid work chambers at both sides of the piston.

The bumper bar is held in a predetermined initial posi¬ tion by hydraulic shock absorber units, which are fast¬ ened to a transverse supporting member. The shock absorber units are aligned in such a way that the piston rods move with the bumper, the connections of the piston rods and the bumper being pivotal.

However, according to this prior art arrangement, no suggestion is made of any expansion or elongation of said bumper, but only of a further hydraulic shock absorber unit, provided on the central longitudinal plane of the motor vehicle and connected to the bumper itself. This further hydraulic shock absorber unit will increase the energy dissipation effect of the bumper in the event of a collision, but without defining any expanded deformation zone of said vehicle.

GB 2,233,423 (Chin-Hun Yang) discloses hydraulic units which are supporting bumpers and are arranged to auto¬ matically extend on application of the vehicle brakes, an impact then causing hydraulic fluid to be expelled through a throttle. Further bumper systems having extendable means therein, are disclosed in US 5,370,429 (Reuber et al.), US 5,011,205 (Liu), US 4,518,183 (Lee) and DE 3808813 (Schubert/MAN Nutzfahrzeuge GmbH).

Objects of the invention

An object of the present invention is to provide an arrangement in a bumper bar, which in a more effective manner can be expanded in an emergency situation, and which in an effective manner can be reset after the oc¬ currence of an emergency situation.

A further object of the present invention, is to provide an arrangement in a bumper bar which can be manufactured from relatively simple and inexpensive parts, at the same time as the overall arrangement can be safely operated and reset.

Summary of the invention

The above objects are achieved in an arrangement as stated in the preamble, which according to the present invention is characterized in that said arrangement com¬ prises means for displacing said bar in relation the vehicle, for thereby, especially in an emergency situa¬ tion, to elongate respectively expand the deformation zones of said vehicle.

In a specific embodiment, the arrangement will comprise means for pneumatic ejection using a pressure accumulator as energy source, which in a further specific embodiment can be combined with spring return means.

More specifically, the arrangement according to the pre- sent invention may comprise means which are combined with conical/cylindrical locking segments which may abut against a cylindrical pipe having a conical flange port- Further features and advantages of the present invention will appear from the following description, taken in connection with the appending drawings, as well as from the enclosed patent claims.

Brief disclosure of the drawings

Fig. 1 is an exploded perspective view of an embodiment of the arrangement according to the invention.

Fig. 2 is a plan view, partly in section, illustrating details of the embodiment illustrated in Fig. 1, the upper part illustrating the expandable bumper means in expanded position, whereas the lower part illustrates said expandable/retractable bumper means in reset or retracted position.

Fig. 3 is a sectional view through another embodiment of an expandable bumper means according to the present in¬ vention, here illustrated in a retracted and ready for use position.

Fig. 4 is a sectional view, similar to Fig. 3, but illus¬ trating the cylinder in its expanded and locked position.

Detailed description of embodiment

In Fig. 1 and Fig. 2, there is illustrated an example of an arrangement according to the present invention, here being designed as a pneumatic, active bumper bar system. However, it is to be understood that such a system can also be designed in several other ways, without departing from the scope of the present invention.

The arrangement illustrated in Fig. 1 and Fig. 2, com- prises a bumper bar 1 which is made of a sturdy material, for example a metal, and more specifically aluminium, and which is covered by a plastic mantle 2, which elements are so arranged that they can be displaced in a direction away from the vehicle (not illustrated) on which said bar 1 and plastic mantle 2 are mounted. This displacement will take place in an emergency situation, for thereby elongating respectively expanding the deformation zone of the vehicle in question. Such an emergency situation can first of all occur during driving of the vehicle, but the system can also be arranged to operate during parking.

The bar 1 with its plastic mantle 2 are supported by two pneumatic cylinders 3A and 3B, respectively, which receive pressure air from a pressure container 4 via a magnet valve 5.

To the right of Fig. 1, one of the cylinders 3A is illus¬ trated with its cylinder rod 3AA in retracted or resting position, whereas to the left in Fig. 1 the second cylin¬ der 3B is illustrated with its cylinder rod 3BB in its expanded or elongated position.

An emergency situation can be sensed through any appro- priate sensors, for example proximity sensors, velocity sensors, etc., there being in Fig. 1 illustrated two sensors 6A and 6B arranged in the plastic mantle 2, said sensors having a connection with for example a computer unit/sensor unit 6, which in turn is connected to said magnet valve 5 controlling the operation of said pressure container 4.

In an appropriate embodiment, when an emergency situation is sensed by any sensor 6A, 6B, or 6, a signal is given to the magnetic valve 5 for thereby releasing pressure from the pressure container 4, so as to expand said pneu¬ matic cylinders 3A and 3B for thereby expanding the de- formation zone of said vehicle. At the same time, as the sensors are sensing an emergency situation, locking seg¬ ments 7 may be activated through "coiled" air hoses, for example through an expansion ring 7A.

If a collision should not occur, but an emergency situa¬ tion has released the extendable pneumatic cylinders 3A and 3B to their expanded positions, a returned spring 8 will pull the respective cylinder back to the start posi- tion when said magnet valve 5 expels the pressure in the system.

Especially in Fig. 2, there are illustrated details of a preferred embodiment of pneumatic cylinders 3A, 3B, wherein said cylinders 3A, 3B are housed in a cylindrical tube 9, i.e. a so-called guiding tube having a centrally located guiding rod 10 therein. The tube 9 is at its rear end attached to the framework of the vehicle in question, whereas at its front end the tube or pipe 9 is provided with a conical flange constituting a conical seat 9A onto which the locking segments 7 can abut when the respective pneumatic cylinder 3A, 3B is in its expanded position, see the upper part of Fig. 2.

In this expanded position, the locking segments 7 will, due to full pressure in the expansion ring 7A contribute to the locking of the respective cylinder rods 3AA, 3BB in their expanded collision accumulating position. Most appropriately, the arrangement comprises means which are adapted to pneumatically and synchronically operate said cylinders 3A and 3B as well as said locking segments 7, i.e. through the same pneumatic conduits, possibly as illustrated in Fig. 1.

In Fig. 2 it is with a first arrow P1 illustrated the supply of air or corresponding fluid to any pneumatic cylinder 3A or 3B, or any cylinder rod 3AA or 3BB. Further, with a second arrow P2 it is illustrated the supply of air or a corresponding fluid to the ring volume 7AA represented by said expansion ring 7A.

Still further, it is to be understood that other embodi¬ ments for supplying air to the cylinders and expansion rings may be contemplated.

At the inner end of each pneumatic cylinder 3A and 3B, respectively, there is arranged an abutment buffer 11 including a sliding segment surrounding said guiding rod 10, and arranged to abut against a closing lid 12 at the front of said tube 9, said abutment buffer 11 also being designed so as to entrain the return spring 8' on its way from retracted to expanded position of the respective cylinder 3A and 3B.

When the emergency situation has ceased to exist, the pneumatic system is depressurized, which means that the locking segments 7 will be released from their locking position as illustrated at the upper part of Fig. 2, to their disengaged position as illustrated in the lower part of Fig. 2, for thereby allowing the return spring 8 to withdraw the respective cylinder 3A, 3B to its reset position, whereafter the system may be pressurized once more and made ready for another emergency situation.

In order to align each cylinder rod 3AA and 3BB, respec¬ tively, when in retracted position, there is at the front end of each cylinder 3A, 3B provided a second, stationary conical seat 12A which is adapted to receive a corres¬ ponding conically shaped alignment ring 12 on the displaceable cylinder rod 3AA and 3BB, respectively.

In Fig. 3 and Fig. 4, which are sections through another embodiment of an expandable bumper means according to the present invention, the locking segments are operated by the pressure supplied to the individual cylinders.

Consequently, the cylinder 103A comprises a cylinder rod 103AA housed in a cylindrical guiding tube 109, which at its rear end defines a pressure chamber 115 receiving an air pressure P101 through an appropriate supply means. At its rear end the cylinder rod 103AA is provided with a conically shaped locking element 107 arranged around a complementary conically shaped guiding buffer 111 having a rim 116 adapted to entrain a first return spring 108 on its way from retracted position, as illustrated in Fig.

3, and to the expanded position, as illustrated in Fig.

4, of said cylinder rod 103AA, for in this latter posi¬ tion to abut against an abutment pipe 117.

Further, the locking segment 107 is arranged to rest against a resilient member, here designed for example as a spring washer 118, for example via a return hook 119, which in turn communicates with a release/locking means 120 adapted to accomplish the following functions:

a) In passive or retracted position of the cylinder rod 103AA, as in Fig. 3, i.e. when no pressure or a low stand-by pressure P101 is supplied to said pressure cham- ber 115, to keep said locking segment 107 in a retracted position to allow for a certain clearance between said locking element 107 and the inner wall of said tube 109.

b) Upon supply of air P101 at a pressure large enough to expand said cylinder rod 103AA rapidly against the force of said first return spring 108, to follow the movement of said cylinder rod 103AA but still maintain its rela¬ tive distance from said spring washer 118 and thereby from said locking segment 107.

c) Upon full stroke of said cylinder rod 103AA to be allowed for a further relative displacement due to the pressure P101 in the expanded pressure chamber 115', and then against the force of a second return spring 121, so at to release said return hook 119 and abut against said spring washer 118 which will press said locking segment 107 forwardly along said guiding buffer 111 to a cylinder rod locking position, see Fig. 4.

d) Upon pressure relief, to allow for the opposite func¬ tional steps to take place, i.e. letting the second return spring 121 go back to its released position, thereby allowing the spring washer 118 to do the same, and thereby also letting the return hook 119 be allowed to retract said locking segment 107 to released position, which in turn will allow the first return spring 108 to retract the cylinder rod 103AA itself to return to its initial passive or retracted position, see Fig. 3.

In its retracted position the cylinder rod 103AA with its release/locking means 120 may appropriately rest against a buffer means 122.

In Fig. 4 there is also illustrated an abrasive ring 123 arranged at the frontend of the tube 109.

The embodiment illustrated in Fig. 3 and 4 will require only one supply conduct to each cylinder.

It is to be understood that the sensor unit 6 may com¬ prise a microprocessor processing all appropriate signals coming from any sensor which may monitor any parameter which can be used for indicating an emergency situation.

Claims

P a t e n t c l a i m s

1. Arrangement in a structure member, especially a structural beam and more specifically a bumper bar (1 ) for a vehicle or vessel, c h a r a c t e r i z e d i n that said arrangement comprises means for displacing said bar (1) in relation to the vehicle, for thereby, especially in an emergency situation, to elongate respectively expand the deforma- tion zones of said vehicle whilst simultaneously enabling bar locking means (7; 107) to be effective.

2. Arrangement as claimed in claim 1 , c h a r a c t e r i z e d i n that said locking means (7; 107) comprise locking segments (7) which are arranged stationary in relation to a bumper bar (1) displacing cylinder rod (3BB), but arranged to exert locking func¬ tion at full stroke of said cylinder rod (3BB).

3. Arrangement as claimed in any of the preceding claims, c h a r a c t e r i z e d i n that said arrangement comprises means (3A), (3B) which are combined with coni¬ cal/cylindrical locking segments (7) adapted to abut against a cylindrical pipe (9) having a first conical seat (9A).

4. Arrangement as claimed in any of the preceding claims, c h a r a c t e r i z e d i n that the arrangement comprises means which are adapted for pneumatic activa¬ tion of said locking segments (7), for example in the form of coiled air hoses, more specifically as at least one expansion ring (7A).

5. Arrangement as claimed in claim 2 - 4, c h a r a c t e r i z e d i n that said locking seg- ment (7) comprises a pneumatic expansion ring (7A) which in an emergency situation is supplied with air or similar fluid (P2), substantially simultaneously with supply of air or similar fluid (P1 ) to respective cylinder (3A, 3B).

6. Arrangement as claimed in claim 1 , c h a r a c t e r i z e d i n that said locking means (7; 107) comprises locking segments (107) which are sub- stantially integral with said cylinder rod (103AA,

103BB), but arranged to exert locking function at full stroke if said cylinder rod (103AA, 103BB).

7. Arrangement as claimed in claim 6, c h a r a c t e r i z e d i n that said locking means comprises a release/locking means (120) which is enabled for its locking function by the same pressure (P101) as used for expanding said cylinder (103A, 103B).

8. Arrangement as claimed in claim 6 or 7, c h a r a c t e r i z e d i n that said release/locking means (120) comprises a spring washer (118) which is adapted to transfer a locking force to the locking segment (107) at full stroke of said cylinder rod (103AA, 103BB).

9. Arrangement as claimed in claim 8, c h a r a c t e r i z e d i n that said release/locking means (120) comprises a second return element, for example a return spring (121) against which said release/locking means (120) will be pressed at the end of the full stroke of said cylinder rod (103AA, 103BB) before said spring washer (118) is influenced to transfer a locking force to said locking segment (107).

10. Arrangement as claimed in claim 7 - 8, c h a r a c t e r i z e d i n that said release/locking means (120) comprises a retraction element, for example a return hook (119) which allows the locking element (107) to be returned when the pressure (P101) is released after an emergency case.

11. Arrangement as claimed in any of the preceding claims, c h a r a c t e r i z e d i n that the arrangement comprises means which are adapted to pneumatically and synchronically operate said cylinders (3A, 3B) and said locking segments (7) .

12. Arrangement as claimed in any of the preceding claims, c h a r a c t e r i z e d i n that the arrangement comprises a second stationary conical seat (12) and a corresponding conical portion (12) on the displaceable cylinder rod (3AA, 3BB) adapted to align each cylinder rod when in retracted position.

13. Arrangement as claimed in claim 1 , c h a r a c t e r i z e d i n that said arrangement comprises means (3A, 3B) for pneumatic ejection using a pressure accumulator (4) as energy source.

14. Arrangement as claimed in claim 1 , c h a r a c t e r i z e d i n that said arrangement comprises means (3A, 3B) which are combined with at least one magnet valve (5) .

15. Arrangement as claimed in any of the preceding claims, c h a r a c t e r i z e d i n that the arrangement is adapted to cooperate with sensors (6A, 6B) for example proximity sensors, velocity sensors, etc., and possibly together with a microcomputer (6), and appropriate compu¬ ter programs.