DEVICE FOR SAFETY BELTS

Abstract: A device for safety belts for vehicles, consisting of a plate-shaped holding part (1) which can be anchored in the vehicle and which is provided with an elongated opening (3) adapted to be travelled through by a belt band (4), wherein along one side of the opening there is disposed a supporting portion with a supporting surface (6) over which the belt band can run. The elongated opening (3) is provided with an oblique lateral portion (10) at each side of a central portion (20), through which the belt band (4) normally runs and which comprises said supporting portion.

Description: Title: Device for safety belts Technical field: The present invention relates to a device for anchoring and guiding belt bands in safety-belt devices . For this , separate ancho¬ ring fittings and guide fittings are provided . These comprise an elongated opening, through which the band extends . Background: Guide fittings for safety belts were previously known , for example from the specification No . 7513419-7 as laid open . With this known fitting, an attempt was made to solve the problem of achieving spreading of the band so that it does not wrinkle. This has been done as a result of the fact that the surface over which the belt band runs , has been provided with notches , between which ridges are formed. A similar device is known from US-PS No . 4.005.904. A further form of guide fitting is known from GB-PS No . 1 280 153. Nevertheless it has been shown in practice that these known guide fittings do not represent any reliable solution of said problem of holding the belt band flat. Technical problem : The anchoring and guide points in said fittings are very sensi- tive parts of a safety belt. At the same time as there is a great demand that the band should be movable at the anchoring or guide point, the band must be guided so that it does not "twist" , that is to say wrinkle so that it breaks or is simply torn off with a momen¬ tary tensile load in the band, which occurs on violent braking or a collisεion , that is to say precisely the circumstances when the band should have its protective function . Furthermore, at the guide fitting, the belt band should be able to run through the fittings with the minimum resistance so as to provide a complete drawing in of the belt band in the case of safet} 7 belts which can be drwan in . The solution : The present invention indicates a solution to said problem of holding the band smoothed out so that it does not wrinkle, which ■ solution involves the fact that the opening through which the belt band is to run is provided with oblique lateral portions in the man¬ ner which is seen from the following description. 5 Advantages : As a result of the invention , the effect is thus achieved that the band is held smooth even under difficult conditions , for example with lateral forces on the band. As a result, abnormal stresses are avoided with the risk of the band tearing apart while at the same • J O time it is easier to handle and runs more easily . It is also of great importance from the physiological point of view that the band should be held flat, because as a result it has the largest possible bearing surface against the body of the wearer of the belt. 1 5 Brief description of drawings : The invention will be described in .more detail below with a pair of examples of embodiment shown on the accompanying drawings , in which Figure 1 shows a side view of a guide fitting according to the invention in a first form of embodiment, Figure 2 shows a cross- 0 section through the guide fitting of Figure 1 on the line II-II, Figure 3 is a view partly broken away, on a larger scale, of a por¬ tion of the guide fitting of Figures 1 and 2, while Figure 4 show's , on a larger scale, a partial view of a portion of the guide fitting and Figure 5 shows the guide fitting in a view from below. Figure 6 5 shows a side view of the guide fitting in another form of embodiment, while Figure 7 shows a cross-section through the guide fitting of Figure 6 on the line VI- VI . Best mode of carrying out the invention : 0 With reference to the form of embodiment shown in Figures 1 - 5 it will be seen that the device according to the invention consists of a holding part 2, which is plate-shaped and anchored in a vehicle or the like via a screw or the like, extending through a hole 2 but not shown in the drawing. The holding part also comprises an elon- 5 gated opening 3 adapted to be travelled through by a belt band 4 which is indicated in chain line in Figures 1 and 2. The example shown relates to a so-called guide fitting, at which the belt band 4 "BtS R OM < is bent at an angle. This fitting is placed, for example, as an upper anchoring point at the outside of the wearer of the belt, the fitting being pivotally mounted about said screw so that the fitting can adapt a suitable position depending on the si2e and position of the wearer of the belt. The belt band extends at one side of the guide fitting to a roller lock, known per se, provided with a spring-loaded roller which tends to draw in the belt band. The roller lock is adapted to lock the belt band against pulling out by means of a mechanism which is adapted to be activated on the one hand by abnormal changes in speed of the vehicle and on the other hand by a certain acceleration of the band. The elongated opening 3 in the holding part 1 comprises a supporting portion 5 with a supporting, surface 6 which is adapted to support the belt band 4. The supporting surface 6 is divided into a plurality of component surfaces as a result of the fact that the supporting portion 5 comprises a plurality of portions 7 which are countersunk in relation to the supporting surface 6 and which are shown on a larger scale in Figure 3. As can be seen from Figures 2 and 1, the countersunk portions 7 extend across the longitudinal direction of the opening 3 and comprise, in their extent, guide edges 8 which serve as lateral guiding for the band 4. According to the invention, the supporting portion 5 is arched and has a relatively large radius of curvature which in the example shown is about 8 mm, and a width which is greatly enlarged in com- parison with conventional guide fittings . This enlarged width is obtained as a result of the fact that the supporting portion 5 pro¬ jects outside the normal thickness of the holding part 1 with lip-like projections 9 at each side of the holding part 1. Following on the lip-like projections , the supporting portion 5 merges into a smaller radius of curvature which is 3 , 2 mm in the example shown . Furthermore, the elongated slot-shaped opening 3 is divided into a central portion 20, in which the belt band 4 is normally adapted to be present and which has a length which is substantially equal to or somewhat exceeds the width of the belt band 4, and two obhque lateral portions 10 into which the central portion merges with bent portions 11. The obhque lateral portions 10 have an angle 12 in relation to the imaginarly line 13 shown in Figure 1 of less than 90° . The line 13 extends between the pivotal centre 14 of the holdin part 1 and the bent portion 11. The slot-shaped opening 3 also has an extremely narrow width and in the example shown is about 2,5 mm wide and is substantially uniform in width with the exception of the enlargement obtained by the countersinking 7 and a possible narrowing off in the obhque lateral portions 10. The lateral portions should not have too great a length , but are considerably shorter than the central portion and are, for example, about 1/5 th of its length. The guide fitting shown in Figures 1 - 5 is composed of a core 15 of a very strong material, for example steel or another metal. As can be seen from Figure 2, the core is completely uniform in thick¬ ness and in this embodiment is completely enclosed in a cover 16 of an easily shaped but relatively strong material, for example plastics . The functional shaping of the holding part 1 is obtained through the easily shaped material. At the hole 2, a bush is formed by the enclosure, and at one side of the fitting the hole has a raised edge 17, which forms a sliding surface in relation to the head of the screw. In the example shown in Figures 6 and 7, the holding part 1 is only enclosed in its low τ er portion with an easily shaped material, for example plastics , while an upper portion following on the hole 2 is completely unenclosed and so is formed only of a portion of the core 15, made of the very strong material. As can be seen from Figures 6 and 7, the lip-like portions , which are here designated by 18, are somewhat less rounded, that is to say the radius of cur¬ vature is further reduced in these portions , while the supporting surface 5 again has an abnormally great radius of curvature in this example . As a result of the construction of the slot-shaped opening 3 according to the invention, with a plurality of countersunk portions 7 and the large arched supporting portion 5 together with the extent of the slot-shaped opening 3 with two obhque lateral portions 10, a combination with particularly favourable characteristics is obtained so far as the guiding of the belt band 4 sideways is concerned and avoiding weakening or breakage in the band because the band twists or is simply torn off as a result of the edge effect and the deforma- tion which occurs in the band in conventional fittings . As a result of the countersunk portions 7, a guiding against sideways movements is obtained, that is to say across the longitudinal direction of the band, which guiding increases with increasing tensile loading because of the tendency of the flexible band to sink down into the counter¬ sunk portions 7, in which case the guide edges 8 serve to guide the band. This applies in particular with woven bands , which normally occur in safetj' belts , which comprise longitudinal threads which tend to move down into the countersunk portions 7 with tensile loading. As a result of the fact that the obhque lateral portions 10 have a bent transition 11 from the central portion , the longitudinal edge portions of the band are enabled to climb up a bit into the lateral portions 10 if such conditions . of force should occur that despite everything, the band is displaced sidew τ ays, for example on a very powerful retardation of the vehicle . This prevents the band from twisting and breaking as a result of jamming in the edges of the opening, which could happen otherwise if there had only been a straight gap . As a result of the inclination of the lateral portions 10 and a suitably adapted angle 12, as mentioned above, a braking of the lateral movement of the band takes place and a tendency to restore it to its normal central position in the central portion . This braking is accentuated by the fact that the slot-shaped opening 3 is kept very narrow and that convex corners 19 are formed in the middle of the bent concave portions 11, and give a further braking effect against lateral movement of the band. The narrow slot-shaped opening 3 leads , through its small width, to the fact that the ten¬ dency of the belt band 4 to twist is further reduced. The shape and size of the supporting portions 5 reduce the resistance which occurs on passage of the band through the guide fitting, both during a slow movement of the band , for example w τ hen it is rolled in, and on powerful acceleration of the band when the band is momentarily exposed to very heavy loading. As a result, the band is prevented from simply being torn off under heavj ** loading, which may occur because of the knife effect which is obtained even with well rounded edges , which have the same width , for example , as the main width of the holding part 1. This is there¬ fore not just a dimensioning of the supporting portion but a new insight into the behaviour of the belt band under heavy loading and precautions to prevent damage to the band with consequent weakenin and breakage, which in turn can lead to serϊus personal injury. Industrial applicability: The invention is not restricted to the examples of embodiment described above and shown in the drawings , but can be varied withi the scope of the following Patent Claims . For example, it is conceiv¬ able that the slot-shaped opening 3 may be made without the obhque lateral portions 10 and so only with the central portion, in which case satisfactory characteristics are achieved by the countersinking and the enlarged supporting portion. The supporting portion does not necessarily need to have a supporting surface in the form of a wall of a cylinder but another arched shaped is conceivable. Further- more, it is conceivable that the countersinkings 7 may be more or less in number, or have a different shape or width from what is shown . The lateral portions 10 may also be formed otherwise, for example with a simple bent shape, in which case the portions 10 simply constitute a bent extension of the bent portions 11. Even though it is an advantage to have a narrow slot-shaped opening, it is naturally conceivable that the opening may have a considerably greater width and that the opening may follow the outline shape of the core instead of comprising the countersunk portion made entirely of plastics material. Furthermore, the holding part 1 may constitute an anchoring fitting instead of a guide fitting, in which case the belt band is laid in a loop through the slot-shaped opening 3 and the end of the band is fixed to the band material outside the fitting by means of seams or the like. In this case, therefore, the band is not intended to be displaced in the longitudinal direction of the band to any great extent but the fitting merely permits a certain movement of the band in relation to the anchoring point. The expression "width of the supporting portion" in Claim 1 refers to the dimension exten¬ ding transversely to the main plane of the holding part 1.

Claims: Patent Claims: 1. A device for safety belts for vehicles or the like and consisting of a plate-shaped holding part (1) which can be anchored in the vehicle and which is provided with an elongated opening (3) adapted to be travelled through by a belt band (4) , while along one side of the opening there is disposed a supporting portion (5) with a sup¬ porting surface (6) over which the belt band is bent at an angle and Λvhich is adapted to take up loading in the longitudinal direction of the band, characterized in that the elongated opening (3) is provided with an obhque lateral portion (10) at each side of a central portion (20) , through which the belt band (4) normally runs and which comprises said supporting portion (5) . 2. A device as claimed in Claim 1, characterized in that both the central portion (20) and the lateral portions (10) of the elongated opening (3) are substantially rectilinear in their longitudinal direc¬ tion, and the central portion has a length which substantially corre¬ sponds to the width of the belt band, while the lateral portions are considerably below this width . 3. A device as claimed in Claim 2, wherein the holding part (1) is pivo tally anchored in the vehicle in a pivot pin (14) , characterized in that the two obhque lateral portions (10) have an angle (12) in relation to a line between said pivot pin (14) and the transition bet¬ ween the central portion and the lateral portions , which angle is equal to or less than 90° . 4. A device as claimed in Claims 1 , 2 or 3, characterized in that the two obhque lateral portions (10) have an opening passage with a height which insignificantly exceeds the intended thickness of the band (4) . 5. A device as claimed, in Claims 1 , 2, 3 or 4, characterized in that said supporting portion (5) comprises a plurahty of poritons (7) which are countersunk in relation to the supporting surface (6) and that the supporting portion (59) is arched in the longitudinal direction of the band with such a great width and such a great radius of curvature that the belt band bears against the supporting portion over the greater proportion of its width even with insignifi¬ cant tensile forces , as at a constant speed of the vehicle . 6. A device as claimed in Claim 5, characterized in that the main radius of curvature of the supporting portion (5) exceeds 6 mm. 7. A device as claimed in Claim 5 or 6, characterized in that the width of the supporting portion (5) in the longitudinal direction of the band exceeds l/5th of the width of the belt band. 8. A device as claimed in one of the preceding Claims , characterize in that the supporting portion (5) projects at each side beyond the main body of the holding part (1) in the intended longitudinal directio of the band.

Inventors: BERG L, SYLVEN H
Applicants: BERG L, LINDBLAD S M, SYLVEN H, LINDBLAD S
Application year: 1980
Main classification: A62B35
IPC codes: B60R22