Safety belt device in a vehicle

Abstract

A belt fitting for a safety belt device in a vehicle that includes a base segment and an insertion tongue connected thereto, in which base segment a belt eye is provided, through which a belt webbing is guided and divides the belt webbing into a shoulder belt segment and a lap belt segment when the safety belt is worn. The belt fitting has a clamping element movable between a release position, such that the belt webbing is freely movable in sliding contact over at least one belt running surface, and a clamping position, in which the belt webbing is tightly clamped between a clamping stop on the base segment and the clamping element in the event of a load or crash. The belt running surface of the belt fitting has a surface contour, which ensures stable transverse guidance of the belt webbing in the event of a load.

Claims

1. A belt fitting for a safety belt device in a vehicle, the belt fitting comprising: a base segment and an insertion tongue connected thereto, wherein the base segment has a belt eye through which a belt webbing is guided and which divides the belt webbing into a shoulder belt segment and a lap belt segment when the safety belt device is buckled; and a clamping element that is adjustable between a release position, in which the belt webbing is freely movable in sliding contact over at least one belt running surface of the belt fitting, and a clamping position, in which the belt webbing is tightly clamped between a clamping stop on the base segment and the clamping element in the event of a load or a crash, wherein the at least one belt running surface of the belt fitting has a surface contour that ensures a stable transverse guidance of the belt webbing in the event of a load or crash if the belt webbing is not yet tightly clamped, the transverse guidance counteracting a transverse force component that acts upon the belt webbing, wherein the at least one belt runninq surface includes two belt running surfaces that are provided on opposite sides of the belt eye, viewed in a longitudinal direction of the belt webbing, wherein one of the two belt running surfaces is formed on the clamping element and another one of the two belt running surfaces is formed on the base segment, and wherein the two belt running surfaces are each provided with the surface contour, and wherein the surface contour includes indentations, furrows, grooves or cross-furrows oriented in a longitudinal direction of the belt webbing.

2. The belt fitting according to claim 1, wherein the indentations of the surface contour are each approximately 2.5 mm wide and approximately 1.5 mm deep, and wherein the grooves are open counter to a direction of movement of the belt webbing such that they have no limiting wall on a front side, such that the grooves are delimited by a base, two opposing lateral side walls and a back side wall.

3. The belt fitting according to claim 1, wherein the clamping element is pivotable around a rotation axis between the release position and the clamping position and may be elastically pretensioned in a direction of the release position, and wherein the clamping element is pivotable into the clamping position in a rotation direction in the event of a load when higher belt forces are applied to the belt webbing.

4. The belt fitting according to claim 1, wherein the clamping element has a clamping contour with the aid of which the belt webbing may be tightly clamped in the clamping position.

5. The belt fitting according to claim 4, wherein the clamping element has the one of the two belt running surfaces, including the surface contour, and the clamping contour, and wherien the surface contour is disposed on the clamping element in a leading manner and the clamping contour is disposed thereon in a trailing manner, viewed in a rotation direction.

6. The belt fitting according to claim 4, a clamping piece that protrudes from the clamping element is provided with the clamping contour, and wherein the belt webbing is clamped between the clamping contour of the clamping piece and the clamping stop of the base segment in the clamping position.

7. The belt fitting according to claim 6, wherein the clamping piece extends along an axial direction of the clamping element and protrudes from the clamping element in a radial direction of the clamping element, wherein an apex of the clamping piece is provided at a middle portion of the clamping piece in the axial direction, the middle portion of the clamping piece corresponding with a middle portion of the clamping element, wherein descending arc segments of the clamping piece extend from the apex on either side thereof towards ends of the clamping element, wherein the apex and the arc segments form the clamping contour of the clamping piece and wherein the belt webbing is clamped between the apex of the clamping piece and the clamping stop of the base segment in the clamping position.

8. The belt fitting according to claim 1, wherein the surface contour extends continuously over the entire belt webbing width in a belt transverse direction.

9. A safety belt device for a vehicle, comprising the belt fitting according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

(2) FIG. 1 shows a detail of a three-point safety belt device in a position of use, in which the vehicle occupant is buckled into the safety belt;

(3) FIG. 2 shows the belt fitting in an exploded view;

(4) FIG. 3 shows an enlarged sectional view along plane of intersection I-I from FIG. 1, in which the clamping element is shown in the release position;

(5) FIG. 4 shows the clamping element in the clamping position in a view corresponding to FIG. 3;

(6) FIG. 5 shows the clamping element, whose belt running surface is provided with the surface contour, in a greatly enlarged and simplified schematic diagram;

(7) FIGS. 6 and 7 each show different variants of the surface contour in the belt running surface of the belt fitting; and

(8) FIG. 8 shows a sectional view along plane of intersection II-II from FIG. 7.

DETAILED DESCRIPTION

(9) In the partial view in FIG. 1, a three-point safety belt formed by a shoulder belt segment 1 and a lap belt segment 3 is shown in a position of use, i.e., with the vehicle occupant buckled into the safety belt. The vehicle seat and the vehicle occupant are not illustrated for reasons of clarity. The upper end of shoulder belt segment 1, which is also not shown, is connected to a retractor, which is not illustrated and which is disposed, for example, in the center pillar. According to FIG. 1, lap belt segment 3 extends from an outer connecting point, which is not illustrated, to a belt fitting 7, which is inserted by an insertion tongue 9 into a belt buckle 11.

(10) Belt fitting 7 is assembled from a base segment 13 and aforementioned insertion tongue 9. Base segment 13 of belt fitting 7 includes a belt eye 15, through which belt webbing 5 is guided. In the safety belt shown in the buckled state in FIG. 1, belt webbing 5 is divided into shoulder belt segment 1 and lap belt segment 3 at belt eye 15.

(11) As is apparent from FIGS. 2 and 3, a bar-shaped clamping element 17 is pivotably hinged around a pivot axis A on base segment 13 of belt fitting 7. During normal vehicle operation, clamping element 17 is elastically pretensioned with the aid of a spring 18 (FIG. 2) in the direction of a release position I shown in FIG. 3. In release position I, belt webbing 5 is freely movably guided in sliding contact over a belt running surface 19 of clamping element 17 and over a belt running surface 24 of base segment 13.

(12) Together with a clamping shoulder 23 formed on base segment 13, clamping element 17 delimits a clamping gap 21 (FIG. 3) in release position I.

(13) FIG. 4 shows the belt fitting in a load event, for example in a crash event. In the event of a crash, much higher belt forces F.sub.B, F.sub.S act upon lap belt segment 3 and shoulder belt segment 1 of the safety belt. As a result, higher belt forces are also applied to clamping element 17, whereby it is translocated into clamping position II in a rotation direction R. In clamping position II, a clamping piece 25 molded onto clamping element 17 presses belt webbing 5 against clamping shoulder 23 with the aid of a clamping force F.sub.K. In this way, lap belt segment 3 is arrested in a safety-beneficial manner in the event of a crash.

(14) According to FIG. 5, clamping piece 25 of clamping element 17 is not contoured in a linear and planar manner, but instead clamping piece 25 has a crown or bulge, with an apex 29 disposed approximately in the middle and with arc segments 31 descending laterally. According to FIG. 5, apex 29 as well as arc segments 31 descending laterally therefrom result in a clamping contour K, which results in clamping force distribution F(b) sketched over belt webbing width b. Apex 29 of the crown projects by a height Δh from a base surface 30 of clamping piece 25, which is smaller than or equal to belt webbing material thickness s (FIG. 1), which is usually in a range of 1.2 mm.

(15) With the aid of clamping contour K shown in FIG. 5, no continuously linear and even course of the clamping force distribution results between the two belt webbing outer edges 33, but instead a nonlinear clamping force distribution results with a maximum clamping force in the middle of belt webbing 5. Accordingly, only a slight or possibly no clamping force at all is applied to outer edges 33 of belt webbing 5.

(16) As mentioned above, belt webbing 5 is guided in release position I (FIG. 3) in sliding contact over belt running surface 19 of clamping element 17. In addition, other belt running surface 24, over which belt webbing 5 is guided in the buckled state of the safety belt, is provided on the opposite side of belt eye 15, viewed in the longitudinal direction of the belt webbing. As is apparent from FIG. 1 as well as from FIGS. 5 through 8, the two belt running surfaces 19, 24 each have a special surface contour 26, for example indentations, furrows or grooves, which are oriented in the longitudinal direction of the belt webbing (FIGS. 6 through 8), or alternatively they have cross-furrows (FIG. 1).

(17) The function of this special surface contour 26 is described below on the basis of a crash event: In a crash event of this type, according to FIG. 1, the buckled-up vehicle occupant is accelerated forward in the direction of travel by a force F.sub.I. The much higher belt forces F.sub.B, F.sub.S also act upon belt fitting 7. Belt buckle 11, including belt fitting 7 inserted therein, is affixed to the vehicle bodyshell via flexible steel cable 28. Belt buckle 11, which is flexibly affixed in this manner, tends to twist in a pulse-like manner together with belt fitting 7 inserted therein in the event of a crash. During this belt buckle twisting (indicated in FIG. 1 by a double arrow represented by 32), a transverse force component F.sub.y, which presses belt webbing 5 in the area of belt eye 15 in the direction of corner area 34 of belt eye 15, is applied to belt webbing 5 in the area of belt eye 15 of belt fitting 7. In the prior art, this results in a transverse shifting of belt webbing 5 into corner area 34 of belt eye 15 and consequently in a very strong flex stress of the belt webbing material in belt eye corner area 34, whereby damage may occur.

(18) To avoid such a transverse shifting of belt webbing 5, belt running surfaces 19, 24 are designed with a special surface contour 26, for example furrows, grooves and/or cross-furrows. Due to increasing belt forces F.sub.S and F.sub.B in the event of a load, the plastic material of belt webbing 5 is pressed into the indentations in surface contour 26 of belt running surfaces 19, 24, as shown in FIG. 8. In this way, an increased form and friction fit results between belt webbing 5 and belt running surface 24 in the transverse direction, whereby transverse force component F.sub.y is effectively counteracted without resulting in a disadvantageous transverse shifting in the direction of corner area 34 of belt eye 15.

(19) Clamping element 17 is shown on its own in FIG. 5. Its belt running surface 19 is provided with a surface contour 26 and is disposed upstream from clamping contour K in rotation direction R. In contrast to FIG. 1, in which belt running surface 24 of belt fitting 7 is formed by cross-furrows, surface counter 26 shown in FIG. 5 is formed by grooves which are disposed in parallel and which are oriented in the longitudinal direction of the belt webbing.

(20) The same also applies to belt running surface 24 of belt fitting 7 shown in FIG. 6, in which surface contour 26 also has longitudinal, parallel grooves.

(21) In FIG. 7, in another variant, the grooves are milled counter to the direction of movement of belt webbing 5, i.e., they have an open design without a limiting wall on the front side. In this way, the form fit between belt webbing 5 and belt running surface 24 may be increased.

(22) The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.