REINFORCEMENT PART FOR A BELT SHAFT, BELT SHAFT, AND END-FITTING TENSIONER

Abstract

A reinforcing member (36) for a belt shaft (10) comprises an elongate central portion (46) and two hooking portions (48) provided at the ends of the central portion (46) adapted to be hung into a hooking slit of a belt shaft body (28) of a belt shaft (10), wherein the central portion (46) includes a retaining portion (50) adapted to be encompassed by the webbing (26) and a supporting portion (58) extending in the longitudinal direction (L) substantially over the entire central portion (46) and being offset relative to a plane (M) which is defined by the retaining portion (50), and wherein retaining lands (60) defining a passage window (62) for the webbing (26) extend between the supporting portion (58) and the retaining portion (50). The invention further provides a belt shaft (10) comprising a belt shaft body (28) as well as an end fitting tensioner (12).

Claims

1-16. (canceled)

17. A reinforcing member (36) for a belt shaft (10), comprising an elongate central portion (46) and two hooking portions (48) provided at the ends of the central portion (46) and adapted to be hung into a hooking silt of a belt shaft body (28) of a belt shaft (10), wherein the central portion (46) includes a retaining portion (50) adapted to be encompassed by the webbing (26) and a supporting portion (58) extending in the longitudinal direction (L) substantially over the entire central portion (46) and being offset relative to a plane (M) defined by the retaining portion (50), and wherein retaining lands (60) defining a passage window (62) for the webbing (28) extend between the supporting portion (58) and the retaining portion (50).

18. The reinforcing member according to claim 17, wherein the retaining portion (50) is double-layered.

19. The reinforcing member according to claim 18, wherein the retaining portion (50) is formed by two lands (52, 54) integrally connected to each other.

20. The reinforcing member according to claim 19, wherein the two lands (52, 54) are interconnected by a bending portion (56).

21. The reinforcing member according to claim 19, wherein the hooking portions (48) extend starting from one of the lands (62, 54) and the supporting portion (58) extends starting from the other one of the two lands (54, 52).

22. The reinforcing member according to claim 19, wherein the hooking portions (48) and the supporting portion (58) extend starting from either of the lands (52, 54).

23. The reinforcing member according to claim 17, wherein the retaining Sands (60) extend from one side of the plane (M) defined by the retaining portion (50) over said plane to the other side.

24. The reinforcing member according to claim 17, wherein the hooking portions (48) are provided with a bearing edge (70) especially stepped in the longitudinal direction (L).

25. The reinforcing member according to claim 17, wherein the hooking portions (48) are provided with a toothed edge (72).

26. The reinforcing member according to claim 25, wherein the toothed edges (72) are bent vis-à-vis a plane (E) defined by the hooking portions (48).

27. The reinforcing member according to claim 25, wherein the toothed edge (72), when viewed in a section perpendicularly to the longitudinal axis (L) of the reinforcing member (36), is located approximately on the same radius as the supporting portion (58) in this area.

28. A belt shaft (10) comprising a belt shaft body (28) and a reinforcing member according to claim 19, the belt shaft body (28) centrally having a recess (34) and comprising two flanges (30) in each of which a hooking slit (42) is provided, wherein the belt shaft body (28) includes a supporting surface (66) for the supporting portion (58) of a reinforcing member (36) adjacent to the recess (34).

29. The belt shaft according to claim 28, wherein the supporting surface includes at least a first partial surface extending in the circumferential direction relative to the belt shaft axis.

30. The belt shaft according to claim 28, wherein the supporting surface includes at least a second partial surface extending radially relative to the belt shaft axis.

31. The belt shaft according to claim 28, wherein a reinforcing member according to any one of the claims 1 to 10 is inserted in the recess (34) so that the hooking portions (48) are located in the hooking slits (42) and the supporting portion (58) is adjacent to the supporting surface (66).

32. An end fitting tensioner (12) for a seat belt, comprising a belt shaft according to claim 31.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Further advantages and features will be evident from the following description in connection with the enclosed drawings, wherein:

[0028] FIGS. 1a to 1c show different views of a belt shaft according to the invention,

[0029] FIG. 2a shows a perspective view of an end fitting tensioner according to the invention,

[0030] FIGS. 2b and 2c show sectional views of the end fitting tensioner of FIG. 2a in the sectional plane II of FIG. 2a,

[0031] FIG. 3 shows a perspective view of a reinforcing member of the belt shaft of FIGS. 1a to 1c,

[0032] FIG. 4 shows a sheet metal part for manufacturing the reinforcing member of FIG. 3,

[0033] FIGS. 5a to 5c show different views of the reinforcing member of FIG. 3,

[0034] FIGS. 6a to 8d show sectional views of the reinforcing member of FIG. 3 in the sectional planes VIa-VId of FIG. 5a,

[0035] FIGS. 7a to 7d show different sectional views of the bolt shaft in the sectional planes VIIa to VIId of FIG. 1c,

[0036] FIG. 8 shows the reinforcing member of FIG. 3 with webbing being inserted,

[0037] FIGS. 9a and 9b show sectional views of the belt shaft of FIG. 1 with webbing being inserted,

[0038] FIGS. 10a and 10b show a state-of-the-art belt shaft in cross-section,

[0039] FIGS. 11a to 11e show different views of a second embodiment of a belt shaft according to the invention,

[0040] FIG. 12 is an exploded view of the belt shaft of FIGS. 11a to 11e,

[0041] FIGS. 13a to 13c show different perspective views of the reinforcing member of the belt shaft of FIGS. 11a to 11e,

[0042] FIGS. 14a to 14c are top views onto the reinforcing member of FIGS. 13a to 13c,

[0043] FIG. 15 shows a sectional view across the reinforcing member of FIGS. 13a to 13c,

[0044] FIG. 16 shows a sheet metal part for manufacturing the reinforcing member of FIGS. 13a to 13c, and

[0045] FIG. 17 is a sectional view of the belt shaft of FIGS. 11a to 11e.

DESCRIPTION

[0046] in FIGS. 1a to c a belt shaft 10 for an end fitting tensioner 12 of a seat best illustrated in FIGS. 2a to c is shown.

[0047] The end fitting tensioner 12 includes a retaining frame 14 having a base plats 16 for mounting the retaining frame 14 fixed to the vehicle as well as two substantially parallel side legs 18 each including a round cutout 20 (see FIGS. 2b and c) for receiving and, resp., bearing the belt shaft 10.At the rim of each of the cutouts 20 a toothing 22 that serves for blocking the belt shaft 10 is provided. As is evident from FIG. 2a, furthermore a tensioning drive 24 (indicated only schematically here) is provided to load the belt shaft 10 in a direction of rotation D for winding webbing 28 (cf.FIGS. 9a and 9b.

[0048] As is evident from FIGS. 1a and 1b, the belt shaft 10 includes a belt shaft body 28 being composed of two flanges 30 provided at the axial ends and a land 32 connecting the flanges 30. Between the flanges 30a recess 34 into which a reinforcing member 36 described hereinafter isinserted is provided. The belt shaft body 23 is preferably made from plastic material.

[0049] A tooth profile 38 adapted to interact with the toothing 22 at the side legs 18 of the retaining frame 14 is provided on each of the flanges 30. Moreover, a torque transmission profile 40 projecting in the axial direction in which a drive element of the tensioning drive 24 may engage, for example a pulley, is provided.

[0050] As can be inferred from FIGS. 2b and c as well as 7a and b, a hooking slit 42 is provided on each flange 30. The hooking silts 42 extend starting from the shell of the flanges 30 on a plane perpendicular to the longitudinal axis L into the flanges 30 in the radial direction, for example, with the hooking slits 42 preferably extending over the entire axial length of the flanges 30.

[0051] The reinforcing member 36 shown in FIG. 3 is made from a planar sheet metal strip 44 shown in FIG. 4.

[0052] The reinforcing member 36 includes a central portion 46 and two hooking portions 48 provided at the longitudinal ends of the central portion 46.

[0053] The central portion 46 has a retaining portion 50 which, as is evident from FIGS. 5c and d, is double-layered with each of the layers being formed of a land 52, 54. The lands 52, 54 are interconnected via a bending portion 56 extending in the longitudinal direction L The retaining portion 50 is formed by folding or bending the sheet metal strip 44.

[0054] In addition, the central portion 46 includes a supporting portion 58 extending in the longitudinal direction L and being spaced from the retaining portion which is connected to the retaining portion 50 by two bent retaining lands 60. A passage window 62 is defined by the retaining lands 60, the supporting portion 58 and the retaining portion 50.

[0055] As is visible in FIGS. 3 and 4, the hooking portions 48 are provided on one of the two lands 54 and the supporting portion 58 extends away from the other land 52. A plane M which is plotted in the FIGS. 6c and d is defined by the two lands 52, 54 of the retaining portion 50.

[0056] As is visible in FIG. 8 as well as in FIGS. 9a and b, the retaining portion 50 is wrapped by an eye 64 formed by the webbing 26 for mounting. The webbing 26 is laid around the retaining portion 50 so that it extends through the passage window 62 and does not contact the supporting portion 58.

[0057] Subsequently the reinforcing member 36 is inserted along with the hooking portions 48 into the hooking slits 42 of the belt shaft body 28 until said hooking portions contact the bottom of the hooking slits 42 (cf. FIGS. 7a and b).

[0058] As is evident from FIGS. 7c and d, the supporting portion 58 in this position of the reinforcing member 36 contacts a supporting surface 66 on the land 32 of the belt shaft body 28.

[0059] When the belt shaft 10 then is moved in the direction of rotation D so as to wind the webbing 26 onto the belt shaft 10, the webbing 26 first contacts a contact face 68 opposed to the supporting surface 66 on the land 32 when viewed in cross-section. When a tensile force Z acts on the webbing 28, pressure forces D1 thus act on the contact face 68. At the same time, pressure forces D2 act on the bottom of the hooking silts 42 via the hooking portions 48. In addition, pressure forces D3 act on the supporting surface 68 of the land 32.

[0060] In FIGS. 10a and b the acting pressure forces are shown in comparison in a belt shaft 10′ having a conventional reinforcing member 36′ without any additional supporting surface 66 or a supporting portion 58, respectively.

[0061] In this case, merely pressure forces D1′ and D2′ are acting, which causes a strongly irregular load of the belt shaft body 28. Since the reinforcing member 36′ does not rest on the land 32′, it can be bent by the tensile forces acting on the webbing. In addition, the forces act exclusively on the hooking silts 42′ and the contact face 68′, thus causing an asymmetric load of the belt shaft body 28′ when viewed in cross-section. Furthermore, the pressure forces D1′ may cause bending stress of the land 32′.

[0062] As is evident from FIG. 9a, the pressure forces D3 acting on the land by the additional support of the reinforcing member 30 via the supporting portion 58 are directed substantially opposite to the pressure forces D1, thus preventing strong bending stress of the land 32. In addition, the forces D1, D2, D3 act on the belt shaft body 28 so that the latter is loaded substantially symmetrically, especially more uniformly so that less deformation of the same will occur.

[0063] This more uniform load is achieved by the supporting portion 58 being offset relative to the plane M which is defined by the retaining portion 50. The central portion 50 especially exhibits a substantially e-shaped design, with the supporting portion 58 being provided at the tree end of the “e”. The hooking portions 48 are provided at the opposite inner end of said “e”.

[0064] Especially the retaining lands 60 extend from a first side with respect to the plane M over said plane M to the other side, in this way, very uniform load transfer, when viewed in cross-section, to the belt shaft body 28 is achieved.

[0065] Moreover, as the reinforcing member 36 can be adapted better to the outer circumference of the belt shaft 10 due to the double-layered design, a rounder cross-section of the belt shaft 10 is obtained (cf. FIG. 9b as compared to 10b), in this way, fewer Imbalances occur during winding of the webbing 26 so that in the case of tensioning a more uniform winding operation is performed.

[0066] As is evident from FIGS. 5a and c the bearing edge 70 of the hooking portions 48 is formed to be stepped in the longitudinal direction. The hooking slits 42 are formed to correspond thereto so that the load application to the flanges 30 is performed more uniformly.

[0067] Opposite to the bearing edges 70 a toothed edge 72 which is bent vis-à-vis a plane E defined by the hooking portions 48 is provided at each of the hooking portions 48 (cf. FIGS. 7a and b).

[0068] As is visible in FIGS. 7a to d said toothed edges 72 are located, when viewed in cross-section perpendicularly to the longitudinal axis L, approximately on the same radius as the supporting portion 58 in this area. Moreover, the toothed edges 72 are located substantially on the same periphery as the tooth profile 38 of the flanges 30. The toothed edge 72 so-to-speak supplements the tooth profile 38 in the area of the hooking slits 42, as can be inferred from FIG. 7a. Thus, the tooth profile 38 is not weakened in the area of these hooking silts 42.

[0069] A second embodiment of a belt shaft 10 according to the invention isillustrated in FIGS. 11a to 11e and 12. As is evident especially from FIG. 12, the structure of the belt shaft body 28 substantially corresponds to that of the belt shaft 10 illustrated in FIGS. 1a to 1c.

[0070] The supporting surface 66 provided on the land 32 of the belt shaft body 28 includes two partial surfaces 74, 76, however. A first partial surface 74 is provided on the circumferential surface of the land 32 and extends in the circumferential direction. A second partial surface 76 extends substantially in the radial direction. The first partial surface 74 is provided in a recess 78.

[0071] The reinforcing member 36 of the belt shaft 10 is shown in detail inFIGS. 13 to 16.

[0072] As is evident from FIG. 16, the reinforcing member 36 is equally made from a planar sheet metal part.

[0073] The reinforcing member 36 also includes a central portion 46, two hooking portions 48 provided at the longitudinal ends of the central portion 46 and a supporting portion 56. The central portion 46 includes a retaining portion 50 equally formed of two lands 52, 54 which are interconnected by a bending portion 56.

[0074] As is especially visible from FIG. 18, in this embodiment the hooking portions 48 are provided on the land 52 from which also the supporting portion 58 extends away.

[0075] The bending portion 56 is bent so that the land 54 is provided on a first side of the land 52, the lands 60 of the supporting portion 58 are bent so that the supporting portion 58 is located on the opposite side of the land 52. Hence, the reinforcing element 36 is s-shaped. when viewed in cross-section. The supporting portion 58 is curved, when viewed in cross-section, in portions substantially along a circular path the radius of which corresponds to the radius of the belt shaft 10.

[0076] As can be inferred from FIG. 17, when the reinforcing member 36 is mounted, the curved supporting portion 58 is adjacent to the belt shaft body 28 with the curved portion fully contacting the first partial surface 74 of the land 32. The retaining lands 60 are adjacent to the second partial surface 76, Hence a larger area of the supporting portion 58 is adjacent to the belt shaft body so that better load transfer to the belt shaft body is possible.

[0077] In addition, by the larger contact surface a lever action acting on the reinforcing member 36 is shifted by the pivot point 80 (cf. FIGS. 9a and 17) approaching the supporting surface 65. In both embodiments, the pivot point 78 is closer to the supporting surface 66 than in a conventional belt shaft 10′.

[0078] The reinforcing member 36 shown in FIGS. 13 to 15 moreover offers the advantage that the cross-section 80 (of. FIG. 16 between the hooking portions 48 and the central portion 46 can be designed to be very wide so that the reinforcing member 36 in total is more stable.