Seat belt retractor bracket.

Abstract

The invention relates to a seat belt retractor support (1a) designed to secure a retractor housing (2) to the body of a motor vehicle. The housing is designed to wind and unwind a seat belt strap (3). The support (1a) is designed to be fixed to the vehicle body and to allow the housing (2) to rotate relative to the support (1a) about an axis of rotation. The support (1a) includes elastic return means (7) designed to resist the rotation of the housing (2) attached to the support (1a) when the tension on the seat belt strap (3) of the housing (2) attached to the support (1a) is less than a predetermined threshold value. The elastic return means (7) are designed to allow the housing (2) attached to the support (1a) to rotate in a predetermined direction when the tension on the strap (3) is greater than a predetermined threshold value. (Figure 2)

Description

Title of the invention: Seat belt reel support.

[0001] The technical field concerns seat belt reel supports, seat belt reel housings, assemblies comprising such a support and a seat belt reel housing and finally vehicles comprising at least one such assembly.

[0002] In terms of road safety, automobile manufacturers must take into account numerous regulations when developing new vehicles in order to ensure the safety of vehicle passengers in the event of a collision. According to these regulations, each passenger in a vehicle must have a seat belt designed to restrain the passenger in the event of an impact. Each belt is secured to the vehicle by at least three anchor points. Seat belts are designed and sized to correspond to a standardized passenger of average build. However, the rear seats of a motor vehicle are frequently occupied by passengers of small build such as children or adolescents. However, in the event of a frontal impact, the belt tends to cause excessive stress on the neck and chest of the passengers. These excessive stresses depend largely on the passenger's build.

[0003] Certain organizations, whose mission is to evaluate the behavior of vehicles in the event of impacts, have developed new procedures in order to evaluate the behavior of the seat belt of a motor vehicle according to the size of the passenger seated on a seat, in particular a rear seat. These new procedures consist of placing one or more pressure sensors between the dummy and the strap to measure the pressures exerted on the shoulder and chest of the dummy in the event of frontal impacts. These procedures use different dummies characteristic of different passengers, in particular a first dummy called "5th percentile dummy" corresponding to a woman of small build and a dummy called "Q10 dummy" corresponding to a pre-adolescent. The risks of injuries are differentiated according to the dummy.Thus, a 5th percentile dummy is likely to experience excessive stresses at the chest level, while a Q10 dummy is likely to experience excessive stresses at the neck level.

[0004] Experience shows that a conventional belt does not exhibit differentiated behavior depending on the size of the passenger and therefore does not minimize the risk of injury for certain categories of passengers. Such a conventional belt will therefore not achieve a satisfactory result during these new procedures.

[0005] Thus, there is a need for a solution making it possible to obtain a belt exhibiting differentiated behavior depending on the size of the passenger seated in the seat.

[0006] The object of the present invention is to overcome the problems set out above. In this technical context, an aim of the present invention is to provide a reel support capable of allowing the rotation of a housing secured to the support, when the safety strap of the housing is subjected to tension during a front impact, in order to move the strap away from the neck towards the shoulder of a passenger.

[0007] For this purpose, the present invention relates to a belt reel support designed to secure to the body of a motor vehicle a reel housing, designed to wind and unwind a seat belt strap, the support being designed to be fixed to the body of the vehicle and to allow rotation of the housing, relative to the support around an axis of rotation, the support comprising elastic return means designed to oppose the rotation of the housing secured to the support, when the tension experienced by the safety strap of the housing, secured to the support, is less than a predetermined threshold value, the elastic return means being designed to allow rotation, in a predefined direction, of the housing, secured to the support, when the tension experienced by the strap is greater than the predetermined threshold value.

[0008] The invention also relates to a safety strap winder housing designed to wind and unwind a safety strap and to be mounted so as to be able to rotate on a winder support according to the invention, the housing comprising a mounting axis projecting from the housing and designed to interact with the elastic return means of the support to allow or prevent rotation of the housing around the mounting axis.

[0009] The invention also relates to an assembly comprising a reel support according to the invention and a reel housing according to the invention, the housing being mounted to move in rotation on the support, the elastic return means opposing the rotation of the housing when the tension experienced by the safety strap of the housing is less than a predetermined threshold value, the elastic return means being designed to allow rotation, in a predefined direction, of the housing when the tension experienced by the strap is greater than the predetermined threshold value.

[0010] The invention finally relates to a motor vehicle having at least one assembly according to the invention.

[0011] Thus, the reel support according to the invention makes it possible to obtain an assembly according to the invention whose behavior is differentiated, in the event of a front impact suffered by the vehicle, depending on the build of the passenger protected by the safety strap. Thus, during a front impact, when the passenger is a child or a pre-adolescent, the elastic return means oppose the rotation of the housing because the tension in the strap does not allow the predetermined threshold value to be reached. When the passenger is a woman of small build, the tension in the strap reaches the predetermined threshold value in the event of an impact and the elastic return means then allow the rotation of the housing. When the housing rotates, the predefined direction is chosen to allow the moving the strap away from the neck of the passenger protected by the strap. Thus, the support allows for differentiated behavior and improves the behavior of the safety strap in the event of a front impact suffered by the vehicle.

[0012] According to one embodiment of the invention, the support is designed to receive a mounting axis, projecting from the housing, in order to secure the housing to the support and allow rotation of the housing around the mounting axis.

[0013] According to one possibility of the support, the elastic return means comprise a spiral spring.

[0014] According to one embodiment, the support comprises a toothed wheel cooperating with a latch to authorize or block the rotation of the toothed wheel, the elastic return means comprising a return spring acting on the latch in order to define the threshold for initiating the rotation of the toothed wheel.

[0015] Advantageously, the elastic return means are designed to interact with the mounting axis to cause a torsional force opposing the rotation of the mounting axis.

[0016] According to one embodiment, the mounting axis comprises at least one twisted cable wound around the mounting axis.

[0017] According to another embodiment, the mounting axis is formed from an elastic torsion bar.

[0018] The invention will be better understood on reading the detailed description which follows, given solely by way of non-limiting example and made with reference to the appended drawings in which:

[0019] [Fig-1] [Fig. 1] represents a perspective and bottom view of an assembly according to the invention;

[0020] [Fig.2] [Fig.2] represents an exploded view of a first embodiment of the assembly according to the invention;

[0021] [Fig.3] [Fig.3] represents a detailed view of a second embodiment of the support according to the invention;

[0022] [Fig.4] [Fig.4] represents a perspective view of an assembly according to the invention implementing elastic return means designed to interact with a mounting axis of the housing to cause a torsion opposing the rotation of the mounting axis;

[0023] [Fig.5] [Fig.5] represents a sectional view along the axis AA of [Fig.4] of a third embodiment of the assembly according to the invention implementing a torsion opposing the rotation of the mounting axis;

[0024] [Fig.6] [Fig.6] represents a detailed view of a housing of a fourth embodiment of the assembly according to the invention implementing a torsion opposing the rotation of the mounting axis.

[0025] In these figures, the same references are used to designate the same elements.

[0026] A belt reel support 1a, 1b, 1c according to the invention, illustrated in Figures 2 to 6, is designed to secure a belt reel housing 2, illustrated in the figures, to the body of a motor vehicle. The reel housing 2 is, in a conventional manner, designed to wind and unwind a safety strap 3 for retaining a passenger 4 seated on a seat, in particular a rear seat, of the vehicle. The support 1a, 1b, 1c and the housing 2 form an assembly 5 according to the invention when the housing 2 is secured to the support 1a, 1b, 1c.

[0027] The support 1a, 1b, 1c is designed to be fixed to the vehicle body at a vehicle fixing plate, not shown. The fixing of the support 1a, 1b, 1c is obtained, for example, by screwing and / or welding. According to one possibility of the invention, the support 1a, 1b, 1c forms a part of the housing 2 and is inseparable from the housing 2.

[0028] The support 1a, 1b, 1c is designed to allow rotation of the housing 2 about an axis of rotation A, illustrated in [Fig.l]. The axis of rotation A corresponds to the vertical axis of the vehicle when the support 1a, 1b, 1c is mounted on the vehicle according to the invention. In order to allow the support 1a, 1b, 1c to be secured to the housing 2, the latter comprises a mounting axis 6, projecting from the housing 2, the rotation of the housing 2 then taking place about the mounting axis 6.

[0029] The support 1a, 1b, 1e further comprises elastic return means 7 designed to oppose the rotation of the housing 2 secured to the support 1a, 1b, 1e, when the tension experienced by the safety strap 3 of the housing 2 is less than a predetermined threshold value, the elastic return means 7 being designed to allow rotation, in a predefined direction, of the housing 2, secured to the support 1a, 1b, 1e, when the tension experienced by the strap 3 is greater than the predetermined threshold value. The predetermined threshold value is chosen so as to be greater than the maximum force observed when restraining a Q10 Dummy, during a front impact. The predetermined threshold value is also chosen to be less than an average force observed when restraining an adult of average build.Thus, when the assembly 5 is mounted on the vehicle according to the invention, in the event of a front impact suffered by the latter, the elastic return means 7 allow the rotation of the housing 2 when the passenger 4 corresponds to a woman of small build, that is to say of build greater than that of a child or a pre-adolescent but less than an adult man of average build.

[0030] The support 1a, 1b, 1c is designed to allow the rotation of the housing 2 in a single direction, i.e. the predefined direction, when the elastic return means 7 cease to oppose the rotation of the housing 2. This predefined direction is chosen to allow to move the safety strap 3 away from the neck of the passenger 4, towards his shoulder. This direction therefore depends on the seat on which the assembly 5 is installed and on the way in which the strap 3 is fastened on the passenger 4.

[0031] As illustrated in [Fig. 2], the support 1a according to a first embodiment has elastic return means 7 comprising a spiral spring 8. Advantageously, the spiral spring 8 is wound in a guide 9, illustrated in [Fig. 2]. The spiral spring 8 is configured to allow rotation to be imparted to the mounting axis 6 when the tension experienced by the safety strap 3 exceeds the predetermined threshold value.

[0032] According to a second embodiment, illustrated in [Fig. 3], the support 1b comprises a toothed wheel 10, having a plurality of notches 11, cooperating with a latch 12 to authorize or block the rotation of the toothed wheel 10 depending on the return force exerted by the elastic return means 7 which comprise for this purpose a return spring 13 acting on the latch 12, in order to define the threshold for initiating the rotation of the toothed wheel 10. Advantageously, the notches 11 make it possible to prevent the housing 2 from rotating in the opposite direction to the predefined direction. Advantageously, the notches 11 have profiles chosen to make it possible to increase or decrease the angle of rotation of the toothed wheel 10 between two successive notches 11.

[0033] [Fig.4] illustrates a support according to two other embodiments which comprise a torsion flywheel 14 having a bore 15 into which the mounting shaft 6 is insertable. In both of these embodiments, the elastic return means 7 are designed to interact with the mounting shaft 6 to cause a torsion force opposing the rotation of the mounting shaft 6.

[0034] Thus, in a third embodiment, illustrated in [Fig. 5], the housing 2 comprises a mounting axis 6 formed of an elastic torsion bar 16. For example, the mounting axis 6 is formed of a cylindrical body 17 made of an elastic material so that it can undergo elastic torsion. The cylindrical body 17 is surrounded by a crown 18 having at least one notch 19 designed to interact with the bore 15 in order to block the sliding of the elastic torsion bar 16 in the bore 15, so that the rotation of the housing 2 about the mounting axis 6 requires a torsion of the elastic torsion bar 16. This torsion is only possible when the tension undergone by the safety strap 3 exceeds the predetermined threshold value.

[0035] Finally, in a fourth embodiment, illustrated in [Fig. 6], the support 1c is adapted to receive a housing 2 comprising at least one twisted cable 20 wound around the mounting axis 6. Thus, the rotation of the housing 2 around the mounting axis 6 requires a twisting of each twisted cable 20.

[0036] Thus, the support 1a, 1b, the winder makes it possible to obtain an assembly 5 whose com behavior is differentiated, in the event of a front impact suffered by the vehicle, depending on the build of the passenger 4 protected by the safety strap 3. Thus, during a front impact, when the passenger 4 is a child or a pre-adolescent, the elastic return means 7 oppose the rotation of the housing 2 because the tension in the strap 3 does not allow the predetermined threshold value to be reached. When the passenger 4 is a woman of small build, the tension in the strap 3 reaches the predetermined threshold value in the event of an impact and the elastic return means 7 then allow the rotation of the housing 2. When the housing 2 rotates, the predefined direction is chosen to allow the movement of the strap 3 in order to move it away from the neck of the passenger 4 protected by the strap 3.

[0037] The invention is not limited to the embodiments of the support and the housing described above, only by way of example, but other embodiments can be designed by those skilled in the art without departing from the scope and scope of the present invention.

Claims

Claims

1. Belt reel support (la, 1b, le) designed to secure to the body of a motor vehicle a reel housing (2), designed to wind and unwind a seat belt strap (3), the support (la, 1b, le) being designed to be fixed to the body of the vehicle and to allow rotation of the housing (2), relative to the support (la, 1b, le) around an axis of rotation (A), the support (la, 1b, le) comprising elastic return means (7) designed to oppose rotation of the housing (2) secured to the support (la, 1b, le), when the tension experienced by the safety strap (3) of the housing (2), secured to the support (la, 1b, le), is less than a predetermined threshold value, the elastic return means (7) being designed to allow rotation, in a predefined direction, of the housing (2), secured to the support (1a, 1b, 1c), when the tension undergone by the strap (3) is greater than the predetermined threshold value.

2. Winder support (la, 1b, le) according to claim 1, characterized in that the support (la, 1b, le) is designed to receive a mounting axis (6), projecting from the housing (2), in order to secure the housing (2) to the support and allow rotation of the housing (2) around the mounting axis (6).

3. Winder support (la) according to claim 1 or 2, characterized in that the elastic return means (7) comprise a spiral spring (8).

4. Winder support (1b) according to claim 1 or 2, characterized in that the support (1b) comprises a toothed wheel (10) cooperating with a latch (12) to allow or block the rotation of the toothed wheel (10), the elastic return means (7) comprising a return spring (13) acting on the latch (12) in order to define the threshold for initiating the rotation of the toothed wheel (10).

5. Winder support (the) according to claim 2, characterized in that the elastic return means (7) are designed to interact with the mounting axis (6) to cause a torsional force opposing the rotation of the mounting axis (6).

6. Safety strap winder housing (2) designed to wind and unwind a safety strap (3) and to be mounted rotatably on a winder support (la, 1b, 1c) according to one of claims 1 to 5, the housing (2) comprising a mounting axis projecting from the housing (2) and designed to interact with the elastic return means (7) of the support (1a, 1b, 1c) to allow or prevent rotation of the housing (2) around the mounting axis (6).

7. Housing (2) according to claim 6, characterized in that the mounting axis (6) comprises at least one twisted cable (20) wound around the mounting axis (6).

8. Housing (2) according to claim 6, characterized in that the mounting axis (6) is formed from an elastic torsion bar (16).

9. Assembly (5) comprising a reel support (la, 1b, 1c) according to one of claims 1 to 5 and a reel housing (2) according to one of claims 6 to 8, the housing (2) being mounted so as to be able to rotate on the support (la, 1b, 1c), the elastic return means (7) opposing the rotation of the housing (2) when the tension experienced by the safety strap (3) of the housing (2) is less than a predetermined threshold value, the elastic return means (7) being designed to allow rotation, in a predefined direction, of the housing (2) when the tension experienced by the strap (3) is greater than the predetermined threshold value.

10. Motor vehicle having at least one assembly (5) according to claim 9.

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