WO2006123375A1

WO2006123375A1 - Safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like

Info

Publication number: WO2006123375A1
Application number: PCT/IT2005/000291
Authority: WO
Inventors: Luciano Parisi; Georgios Tarazas
Original assignee: Luciano Parisi; Georgios Tarazas
Priority date: 2005-05-20
Filing date: 2005-05-20
Publication date: 2006-11-23

Abstract

A safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like, comprising a device body (2) that forms at least one region of contact (3) with a flexible element (4) that can be tensioned, the contact region (3) being adapted to engage slidingly and with friction the flexible element (4) as a consequence of a longitudinal movement of the flexible element (4) due to its actuation by tension.

Description

SAFETY DEVICE FOR ABSORBING TENSION LOADS APPLIED TO FLEXIBLE ELEMENTS, PARTICULARLY FOR SEATBELTS OR THE LIKE Technical Field The present invention relates to a safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like. Background Art

As is known, currently, cars are provided with seatbelts in order to ensure the safety or at least limit the possibility of injury of the driver and passengers in case of accident. .

Generally, a seatbelt for cars comprises a flexible element, commonly constituted by webbing, which unwinds from a takeup spool, which is rotatably supported by the frame of the vehicle and is positioned, during use, so as to wrap diagonally around the chest of the user and transversely, by means of a guiding element, the lower region of the user's trunk.

The belt takeup spool is usually provided with inertial locking means, which in case of accident of the vehicle automatically and immediately lock rotation of the takeup spool, so that the belt can retain the user adequately, contrasting his forward movement produced by inertial forces. However, it has been found that in case of an impact of the vehicle with intense deceleration thereof, the user may strike the locked seatbelt by inertia so violently as to be severely injured at the chest due to the intense tensioning stresses that are discharged by reaction from the belt onto the user. In order to try to solve the problem described above, devices have been devised which in practice allow the spool to release a preset portion of belt when the user strikes the locked belt, so as to limit the loads that are transmitted to the user.

However, these devices have a complex structure and are not easily and rapidly applicable to seatbelts already installed in cars. Disclosure of the Invention

The aim of the present invention is to eliminate the drawbacks of the background art by providing a safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like, which allows to significantly reduce the risks of injury linked to the use of seatbelts.

Within this aim, an object of the present invention is to provide a safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like, that can be applied effectively not only in the field of seatbelts but also in other fields of technology in which it is necessary to limit the effects caused by tension loads that act on flexible elements, such as for example cables, ropes or webbing and the like.

Another object of the present invention is to provide a safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like, that is capable of giving the greatest assurances of reliability in operation.

A further object of the invention is to provide a safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like, that can be also installed on seatbelts that are currently already in use.

A still further object of the present invention is to provide a safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like that is structurally very simple, so that it can be manufactured and installed at low cost. This aim and these and other objects that will become better apparent hereinafter are achieved by a safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like, characterized in that it comprises a device body that forms at least one region of contact with a flexible element that can be tensioned, said at least one contact region being adapted to engage slidingly and with friction said flexible element as a consequence of a longitudinal movement of said flexible element due to its actuation by tension.

Brief Description of the Drawings

Further characteristics and advantages of the invention will become better apparent from the description of some preferred but not exclusive embodiments of the safety device according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figure 1 is a schematic view of a possible practical application of the invention; Figure 2 is a schematic longitudinal sectional view of an embodiment of the safety device according to the invention;

Figure 3 is an exploded perspective view of an embodiment of the safety device according to the invention, with parts shown in phantom lines; Figure 4 is a view of the device according to the invention, coupled to a linear sliding guide;

Figure 5 is a schematic perspective view of an intermediate step of the assembly of a possible embodiment of the device according to the invention;

Figure 6 is a plan view of a half-shell that forms an external box-like enclosure for the device according to the invention;

Figure 7 is a side elevation view of the half-shell of Figure 6;

Figure 8 is a sectional view, taken along the line VIII-VIII of Figure 6;

Figure 9 is a transverse sectional view of an embodiment of the device according to the invention;

Figure 10 is a schematic view of a possible application of the invention to a car. Ways of carrying out the Invention

In the examples of embodiments that follow, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other examples of embodiments.

Moreover, it is noted that anything found to be already known during the patenting process is understood not to be claimed and to be the subject of a proper disclaimer.

With reference to the figures, a safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like, according to the invention, generally designated by the reference numeral 1, comprises a device body 2, which forms at least one region of contact 3 with a flexible element 4 to be actuated by tension.

Usually, the flexible element 4 is provided by an elongated element which, if the invention is applied to seatbelts, is preferably constituted by the webbing of the belt proper.

It should be noted that in other applications the flexible element can be constituted by a cable, a rope or other similar elements.

According to the particular aspect of the invention, the contact region

3 is adapted to engage slidingly, generating friction, the flexible element 4 as a consequence of a longitudinal movement thereof produced by its actuation by tension, so as to absorb the energy linked to the tensioning force of the flexible element 4, consequently reducing its effects.

Naturally, the amount of the energy dissipation thus provided varies according to the degree of friction between the contact region 3 and the flexible element 4 and therefore depending on the type of material used for their manufacture. Advantageously, in order to provide the contact regions 3, one or more engagement pins 5 are provided which are supported by the body 2 of the device. In practice, the flexible element 4 winds around at least one portion of the lateral surface of the engagement pins 5, which accordingly make contact with friction with said flexible element 4. Conveniently, the engagement pins 5 are spaced and optionally offset laterally with respect to each other, so as to form a winding path for the flexible element 4, which helps to increase the effect of absorbing the tensioning load.

In one example of embodiment of the invention that is applied particularly to seatbelts, there are also means for varying the useful length of the flexible element 4, which are supported by the body 2 of the device and are designed to increase the useful length of the flexible element 4 when it is tensioned.

More particularly, said means for varying the useful length of the flexible element 4 can be activated preferably when a preset tension load applied to the flexible element 4 is exceeded and conveniently comprise a takeup element 6 for the flexible element 4, which is supported rotatably by the body 2 of the device. In particular, the flexible element 4 is connected to the takeup element 6 and can be wound onto it for a certain extent. It should be noted that the flexible element 4 can wind around the takeup element 6 with an intermediate portion and can engage at least one pair of engagement pins 5 arranged on opposite sides with respect to the takeup element 6, as shown in Figure 2.

Advantageously, the takeup element 6 is connected to elastic return means 25, which are adapted to produce an elastic reaction that contrasts rotation of the takeup element 6 in the direction in which the useful length of the flexible element 4 increases. As will become better apparent hereinafter, said elastic return means 25 in practice provide a damping of the stresses applied to the flexible element 4. Conveniently, the elastic return means 25 can be structured so as to generate a variable elastic reaction, which preferably increases as a function of the angular position of the takeup element 6 with respect to a predefined inactive position.

By way of example, the elastic return means 25 can be constituted by a helical or spiral spring or can be constituted by a gas damper or other fluid-operated shock absorber, optionally with a preloading that can be adjusted by way of preloading means, which can be constituted for example by control screws or other similar per se known elements or by electronically controlled devices, which are also per se known. To complete the takeup element 6, it is optionally possible to provide a locking element, for example of the snap-acting type, which is designed to keep the rotation of the takeup element 6 locked at least until the traction applied to the flexible element 4 exceeds a preset value.

According to a possible example of embodiment, the takeup element 6 is provided with a contoured body 7, which has a variable radius and on which the flexible element 4 can be wound partially.

More preferably, there are two contoured bodies 7 having a variable radius, which are opposite one another and can rotate rigidly about a single rotation axis, which is advantageously located in a position that is intermediate between them.

In particular, the flexible element 4 can be wound onto the contoured bodies 7 with opposite winding directions and passes through the space delimited by the contoured bodies 7.

The radius of the contoured bodies 7 is conveniently designed so as to obtain, in cooperation with the elastic return means 25, a constant or gradually increasing retention on the flexible element 4 in order to contrast the tensioning action applied thereto.

More particularly, with the rotation of the contoured bodies 7 in the unwinding direction of the flexible element 4, a gradual reduction of their radius advantageously occurs, so that the torque transmitted to the takeup element 6 by the tension load applied to the flexible element 4 can be reduced due to the gradual reduction of the distance between the rotation axis of the takeup element 6 and the point where the flexible element 4 disengages from said takeup element 6. Accordingly, the torque transmitted by the tension stresses to the takeup element 6 can be effectively counterbalanced by the contrast torque applied by the elastic return means 25 to the takeup element 6, since such contrast torque, by being preferably of the gradually increasing type, allows to completely damp the tensioning load of the flexible element 4 (which, as mentioned, decreases gradually) and to provide an adequate takeup action of the flexible element 4.

Conveniently, an intermediate portion 4a of the flexible element 4 is rigidly connected to at least one of the contoured bodies 7 by way of fixing means, which advantageously comprise two retention elements 8, which are interposed between the contoured bodies 7 and the flexible element 4 and are pushed elastically against the intermediate portion 4a on opposite sides, so as to provide a stable anchoring of the flexible element 4 to the contoured bodies 7.

Preferably, the retention elements 8 are constituted by elastically deformable bodies, which are made for example of rubber and are accommodated in appropriately provided recesses 7a provided in the contoured bodies 7.

In the embodiment shown in Figure 3, the body 2 of the device is advantageously provided in at least two parts 2a and 2b that can be coupled to each other, interposing between them the flexible element 4. This embodiment is particularly adapted to apply rapidly and easily the device according to the invention to seatbelts currently in use.

For example, the body 2 of the device can be provided in practice with two half-portions 9a and 9b, which can be coupled so as to provide a space that is comprised between them and substantially defines a seat in which the takeup element 6 is rotatably accommodated.

Conveniently, the half-portions 9a and 9b rotatably support respective pulleys 10a and 10b which, when the half-portions 9a and 9b are coupled, are coaxial to each other and face each other.

Advantageously, each pulley 10a and 10b is accommodated in a recess 32, which is formed in the corresponding half-portion 9a and 9b and is provided, on its face that is directed toward the corresponding half- portion 9a and 9b, with an axial rotation pin 33, which is supported conveniently by the corresponding half-portion 9a and 9b by interposing bearings 34. As shown in the example of Figure 3, the pulleys 10a and 10b are associated, so as to rotate rigidly about their respective axis, with a corresponding contoured body 7 in a peripheral region of their face that lies opposite the face directed toward the respective half-portions 9a and 9b.

Advantageously, when the half-portions 9a and 9b are coupled to each other, each contoured body 7 is coupled to the pulley of the other body.

More particularly, each contoured body 7 is provided with an engagement seat 11, which can be engaged by a corresponding abutment pin

12, which is associated with the pulley that supports the other contoured body 7. With the arrangement described above, once the two half-portions 9a and 9b have been joined, the rotation axis about which the contoured bodies 7 can rotate coincides with the axis of the pulleys 10a and 10b.

Moreover, it should be noted that each contoured body 7 can optionally be provided, on both of its opposite ends meant to be connected to the pulleys 10a and 10b, with engagement seats 11 for coupling to corresponding abutment pins 12 supported by the pulleys 10a and 10b.

Advantageously, one or each pulley 10a and 10b is connected to the elastic return means 25, which can be arranged for example in an appropriately provided receptacle 26, which optionally provides a corresponding protrusion 13 on the corresponding half-shell 9a and 9b.

Again with reference to the example shown in Figure 3, the half- portions 9a and 9b respectively support the engagement pins 5 on opposite sides with respect to the corresponding pulleys 10a and 10b.

Advantageously, the engagement pins 5 supported by one half- portion are arranged complementarily with respect to the pins of the other half-portion, so that when the half-portions 9a and 9b are joined the engagement pins 5 are arranged substantially side by side so as to form a winding path for the flexible element 4, as mentioned earlier.

More particularly, each half-portion 9a and 9b has at least one engagement pin 5, which is located on one side with respect to the corresponding pulley 10a and 10b, and at least one pair of engagement pins 5, which are arranged on the opposite side, so that once the half-portions 9a and 9b have been joined there are at least three engagement pins 5 arranged side-by-side on both sides with respect to the pulleys 10a and 10b and therefore with respect to the takeup element 6.

It should be added to the above that the body of the device 2 is preferably completed by an external box-like enclosure, which is advantageously constituted by two half-shells 27, which can be coupled by interlocking means, screws or similar elements. The box-like enclosure thus provided defines internally a cavity 28 in which it is possible to accommodate the half-portions 9a and 9b.

In particular, on the internal surface of each half-shell 27 abutment seats 30 are advantageously provided, which are adapted to engage the peripheral regions of the half-portions 9a and 9b. In order to install the device according to the invention on the flexible element 4, and in particular on the webbing that forms a seatbelt, the half- portions 9a and 9b are positioned so that the respective contoured bodies 7 are moved into contact, on their outer lateral surface, with respective proximate portions of the webbing and on respective opposite faces of said webbing, as shown in Figure 5.

At this point, the half-portions 9a and 9b are moved mutually closer, bringing a portion of webbing arranged between said proximate portions into a position that is interposed between the contoured bodies 7, and then said half-portions are coupled to the half-shells 27, so as to complete the assembly of the device according to the invention. Operation of the invention is as follows.

With particular reference to the application of the invention to a seatbelt, the device according to the invention is associated with the webbing of the seatbelt, for example by installing it in the manner described above and arranging it preferably between the portion 15 of the webbing that extends, during use, transversely to the lower part of the user's trunk and the point 16 where the webbing is fixed to the frame 17 of the vehicle, as shown in Figure 1.

If a deceleration of the vehicle that causes the impact of the user against the locked belt occurs, the stress produced by the impact is transmitted from the webbing of the belt to the device according to the invention and rotationally actuates the takeup element 6, causing an elongation of the webbing of the belt that helps to reduce the forces discharged by reaction onto the user. The traction stress produced on the webbing as a consequence of the impact is therefore at least partially dissipated by the friction produced by the sliding of the webbing on the surface of the engagement pins 5 and is further damped by the elastic return means 25 that act on the takeup element 6, so as to achieve a significant reduction of the stress peaks transmitted to the user.

It should be noted that if the device according to the invention is installed directly on a motor vehicle, the body 2 of the device is preferably associated with the frame 17 of the vehicle and in particular is mounted on a linear sliding guide 21, which extends along the lateral post that generally accommodates the spool of the seatbelt and is usually arranged laterally to the seat 20, advantageously providing a guiding roller 31, which is designed to engage the flexible element 4 constituted by the webbing of the seatbelt, in order to provide a portion of said webbing that is substantially parallel to the linear sliding guide 21. It should be noted that the device according to the invention can be used, as mentioned earlier, also in other fields of application in which it is very important to be able to limit the effects caused by traction stresses discharged onto flexible elements, such as for example antifall devices for sports climbing. In practice it has been found that the device according to the invention achieves the intended aim, since thanks to the presence of the contact regions and to the damping contribution of the elastic return means it considerably reduces the peaks of the stresses discharged onto the seatbelt and by reaction onto the user himself when an accident occurs, consequently limiting the risks of injury.

All the characteristics of the invention described above as advantageous, convenient or the like may also be omitted or be replaced with equivalents.

The individual characteristics described with reference to general teachings or particular embodiments may all be present in other embodiments or may replace characteristics in said embodiments.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. All the details may further be replaced with other technically equivalent elements.

In practice, the materials employed, so long as they are compatible with the specific use, as well as the contingent shapes and dimensions, may be any according to requirements. Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A safety device for absorbing tension loads applied to flexible elements, particularly for seatbelts or the like, characterized in that it comprises a device body (2) that forms at least one region of contact (3) with a flexible element (4) that can be tensioned, said at least one contact region (3) being adapted to engage slidingly and with friction said flexible element (4) as a consequence of a longitudinal movement of said flexible element (4) due to its actuation by tension.

2. The safety device according to claim 1, characterized in that said at least one contact region (3) is formed by at least one engagement pin (5) that is supported by said device body (2), said flexible element (4) winding around at least one portion of the lateral surface of said at least one engagement pin (5).

3. The safety device according to claim 1, characterized in that it comprises a plurality of engagement pins (5) for said flexible element (4), which are mutually spaced so as to form a winding path for said flexible element (4).

4. The safety device according to one or more of the preceding claims, characterized in that said device body supports means for varying the useful length of said flexible element (4), which are adapted to increase the useful length of said flexible element (4) as a consequence of the tensioning of said flexible element (4).

5. The safety device according to one or more of the preceding claims, characterized in that said means for varying the useful length of said flexible element (4) can be activated when a preset tensioning load applied to said flexible element (4) is exceeded.

6. The safety device according to one or more of the preceding claims, characterized in that said means for varying the useful length of said flexible element (4) comprise a takeup element (6) for said flexible element (4), said takeup element (6) being supported rotatably by said device body (2) and being connected to elastic return means (25).

7. The safety device according to one or more of the preceding claims, characterized in that said flexible element (4) winds around said takeup element (6) with an intermediate portion, at least one pair of said engagement pins (5) being provided, said pins being arranged on mutually opposite sides with respect to said takeup element (6).

8. The safety device according to one or more of the preceding claims, characterized in that said takeup element (6) comprises at least one contoured body (7) that has a variable radius and around which said flexible element (4) winds with at least one portion.

9. The safety device according to one or more of the preceding claims, characterized in that said takeup element (6) comprises two contoured bodies (7), which have a variable radius, can rotate rigidly about a single rotation axis and are mutually opposite with respect to said single rotation axis, said flexible element (4) unwinding around said contoured bodies (7) having a variable radius and in the space comprised between them.

10. The safety device according to one or more of the preceding claims, characterized in that it comprises means for fixing an intermediate portion (4a) of said flexible element (4) to at least one of said contoured bodies having a variable radius.

11. The safety device according to one or more of the preceding claims, characterized in that said fixing means comprise two retention elements (8), which act on opposite sides with respect to the longitudinal extension of said flexible element (4) and are pushed elastically against said intermediate portion (4a).

12. The safety device according to one or more of the preceding claims, characterized in that said device body (2) is made of at least two parts that can be coupled with the interposition of said flexible element (4).

13. The safety device according to one or more of the preceding claims, characterized in that said device body (2) comprises two half- portions (9a, 9b), which are opposite and rotatably support respective pulleys (10a, 10b), which are connected, in diametrical points of respective facing faces, to said contoured bodies (7) having a variable radius, said half- portions (9a, 9b) further supporting, complementarily and laterally with respect to the respective pulleys (10a, 10b), at least one pair of said engagement pins (5) on one side, and at least one of said engagement pins (5) on the opposite side.

14. The safety device according to one or more of the preceding claims, characterized in that said device body (2) comprises a box-like enclosure, which is formed by two half-shells (27), which can be coupled.

15. The safety device according to one or more of the preceding claims, characterized in that said flexible element (4) is constituted by a cable or webbing.

16. The safety device according to one or more of the preceding claims, characterized in that said webbing provides a seatbelt.

17. The safety device according to one or more of the preceding claims, characterized in that said device body (2) is fitted so that it can slide along a lateral post of the frame (17) of a vehicle.