EP0129248B2 - Safety belt buckle - Google Patents

Description

The invention relates to a lock for seat belts in means of transport, with a lock housing and an insertable into an opening thereof and to be locked by at least one locking device in the housing, acted upon by a spring-loaded ejector lock tongue.

Belt buckles of this type are known for example from DE-AS 2 160 069, US-PS 3 807 000 and DE-GM 7 438 663 and 7 525 646. Belt buckles of this type have an ejector, which is loaded by an ejector spring in the direction of the insertion opening for the lock tongue and presses the lock tongue in the inserted state against the locking device.

All these buckles have in common that rattling noises occur while driving over bumps and due to vibrations in the drive area of the motor vehicle in question, which are caused by the fact that the metallic lock tongue in the lock housing make small movements and rattles on the parts of the lock housing.

These movements are not prevented by the load on the lock tongue by means of the spring-loaded ejector, also because there is play between the lock housing and the inserted lock tongue for design and manufacturing reasons, so that the lock rattles again and again. This affects the driving comfort.

From DE-A1-19 45 736 a belt buckle is already known, in which the locking and unlocking device is formed on the lock tongue; the known lock has a spring to the side of the insertion path for the lock tongue, which are tensioned when the lock tongue is inserted, press the lock tongue in the locked state of the lock in the direction of the insertion opening and when the lock is unlocked, the lock tongue is released by sudden ejection from the lock support. However, this only prevents the lock tongue from rattling on the locking part.

From DE-A1-21 07 661 a lock is also known, in the insertion opening of which a funnel-shaped widening housing part is inserted, which at least in places encompasses the lock tongue and thus largely prevents the lock tongue from rattling. However, the housing part comprises the lock tongue only in the direction transverse to the main plane of the lock tongue. If this measure prevents rattling of the lock tongue, the funnel part must however completely enclose the lock tongue without any play, which would, however, involve considerable frictional forces when the lock tongue is inserted; the lock tongue would then only have to be inserted in a straight line on the perpendicular bisection of the insertion funnel in order not to damage the guidance of the lock tongue in the long term.

Attempts have also been made to dampen the rattling noises by sheathing the lock tongue with plastic and / or by producing certain housing parts with plastic (DE-A1-3 128 139), but this measure also does not prevent rattling due to the given scope.

The invention is therefore based on the object of providing a lock for seat belts in passenger transport means, in particular motor vehicles, in which such rattling noises can no longer occur. The measures in this regard should be able to be implemented with little effort.

The achievement of this task results from the features of the main claim. Advantageous refinements and developments are listed in the subclaims and other application documents.

The invention provides that in addition to the locking device on the two narrow sides of the insertion opening for the lock tongue in the lock housing, an approximately S-shaped spring element is arranged, which projects laterally with a reference surface into the path to be traversed by the lock tongue during insertion, the S-train is in the plane of the lock tongue or parallel to it and the upper S-arm acts on the lock tongue on its respective side running obliquely to its longitudinal axis with a force component against the direction of insertion and transversely thereto, and that the bow of the S -Form of the spring element is straightened and provided with an outwardly open groove for receiving the tongue edge.

The invention has the advantage that the spring elements arranged on the narrow sides of the insertion opening touch, guide and center the lock tongue from the sides during their movements; due to the force component acting transversely to their insertion direction as well as counteracting force, the lock tongue is pretensioned in the housing in the area of the insertion opening in addition to the load emanating from the ejector spring, so that lateral movements of the lock tongue and rattling on the side housing parts are avoided; the groove provided in the surface of the S-shaped spring elements which touches the lock tongue also centers and fixes the lock tongue transversely to its main plane, so that rattling noises are avoided in this direction of movement.

Another advantage arises from the fact that the decocking without any known lock whose design effort is easy to carry out.

In a preferred embodiment of the invention, the spring elements are arranged such that the lock tongue comes into contact with the spring elements shortly before reaching the point at which the locking member engages in the lock tongue and has tensioned the spring elements when the said point has been reached and thereby itself is under tension.

It is an advantageous aspect of the invention if the shape of the spring elements with respect to curvature, length, material accumulation and / or distance from adjacent housing parts is selected such that the spring forces change when the lock tongue is inserted during its travel up to the moment of engagement, in particular before reduce the click so far that it can be clearly felt by the person buckling up.

According to preferred embodiments of the invention, the spring elements of the lock can be manufactured as injection-molded parts made of plastic either in one piece or easily assembled by means of clip connections. Since seat belts for motor vehicles have to be mass-produced in large quantities, any contribution to reducing the manufacturing outlay and simplifying assembly is of considerable importance.

• Fig. 1 ein Gurtschloß für einen Kraftfahrzeug-Sicherheitsgurt, im senkrechten Längsmittenschnitt,
• Fig. 2 einen Gurtschloß-Ausschnitt in Grundriß-Ansicht mit zwei verschiedenen Darstellungen beiderseits der Längsmittenlinie,
• Fig. 3 ein Federelement in schaubildlicher Darstellung,
• Fig. 4 zwei durch Steg verbundene Federelemente als selbständiges Einbauteil,

In the drawing, exemplary embodiments of the invention are shown in a simplified representation, which are explained below. Show it:

• 1 is a belt buckle for a motor vehicle seat belt, in the vertical longitudinal center section,
• 2 a belt buckle section in plan view with two different representations on either side of the longitudinal center line,
• 3 shows a spring element in a diagrammatic representation,
• 4 two spring elements connected by web as an independent installation part,

The conventionally constructed buckle shown in FIG. 1 has a so-called two-plate housing 10 with a web 11 running between the two plates for a plate-shaped lock tongue 12. This has an opening 13 into which a locking member arranged orthogonally to the lock housing plates 10 and to the lock tongue 12 14 can snap to close the buckle. To remove the locking member 14 and thus to open the lock, a finger button 15 is used, on which fork-shaped projections 16 are formed, which enclose the locking member 14. A compression spring 17 loads the locking member 14 from above, so that it constantly strives in the locking position. Instead of the pivotable finger key 15, a sliding key (not shown) can also be provided.

The path 11 for the lock tongue 12 is on the one hand open to the outside and there forms a funnel-like insertion opening 18 for the lock tongue; on the opposite side, the web 11 is closed by a plate-shaped connecting member 19 for an anchoring part 20. A rivet 21 is used to connect the lock housing 10 to the connecting member 19. An ejector 22 is mounted for longitudinal movement in the central region of the track 11 and is supported on two side ejector springs 23 which close the ejector 22 in the direction of the insertion opening 18 for the lock tongue 12 push strive. When the lock tongue 12 is inserted, it and the ejector 22 are in contact with one another.

The lock housing 10 formed from two plates, which absorbs the western belt forces and introduces it into the vehicle via the anchoring part 20, is externally covered by appropriately and attractively shaped plastic caps, namely by an upper cap 24 and a lower cap 25. These can be complementary designs the insertion opening 18 and the possibility of access to the finger key 15 freely. The caps are centered on one another preferably by means of pins and corresponding holes, of which a hole 26 is shown in FIG. 3. In addition, connecting screws, not shown, are provided. The inner surfaces of the cover caps 24, 25 are profiled to perform various functions, for example the lower cap 25 has upstanding ribs 27 for positioning and holding the housing 10; Furthermore, a ramp 28 is arranged for the lock tongue 12, which is inserted in the direction of arrow 29 (Fig. 3).

When the person using the seat belt buckles up, he leads the lock tongue 12 to the opening 18 of the lock and puts the tongue into the track 11 of the housing 10 until the locking member 14 engages in the opening 13, which can be regularly felt and / or is audible. To open the lock, the button 15 is pressed, whereupon the locking member 14 leaves the opening 13 upwards and the lock tongue 12 is ejected from the web 11 and through the opening 18 under the action of the ejector 22. Since the parts of the housing 10 and the lock tongue 12 are dimensioned so that the lock tongue can be moved with play in the housing for reasons of manufacture and ease of use, rattling noises occur again and again when the seat belt buckle is closed, especially when the road is bumpy and the engine speed is critical in the lock by audibly abutting the metal parts of the housing, lock tongue and locking element, in particular in the direction transverse to the longitudinal axis of the lock, but also in other directions. This can cause irritation and also material impairment causes.

Figures 2 and 3 show measures to prevent noise in the form of spring elements 30, 31 which are arranged on both sides of the insertion opening 18 for the lock tongue 12. These spring elements compensate for the above-mentioned play between the relevant components of the castle by touching, guiding and centering the lock tongue 12 from the sides during their movements in the path 11. In addition, the spring elements apply a differentiated preload to the lock tongue against the direction of insertion. As a result, the effect of the ejector 22 is less supported than it is made particularly clear when the plug is inserted when the engagement takes place. This largely eliminates the need for hearing after hearing is unsafe, for example when the engine is started. Finally, the spring elements 30, 31 can also compensate for tilting of the lock tongue 12.

In the exemplary embodiments according to FIGS. 2 and 3, the spring elements 30, 31 are designed to cooperate with a lock tongue 12, which has a stepped layout, i. H. the lock tongue 12 here has a front part 32 intended for entry into the web 11 with parallel side edges 33, to which a wider base part 35 adjoins via edges 34 which run obliquely outwards, the latter having the usual slot for looping through the actual seat belt webbing (not shown) contains. The spring elements 30, 31 act on both the lock tongue front part 32 with edges 33 and the base part 35 with oblique edges 34. This results in frictional connections in different directions. Even lock tongues without inclined edges 34 can be influenced by the position of the spring elements so that no rattling noises occur.

The spring elements 30, 31 are made of resilient, flexible plastic and roughly approximate the design of an S-shaped band, the material thickness of which varies. At the ends of the S shape, extensions can be provided, which in particular perform fastening and support functions. Due to the two opposing arches of the S shape, multiple spring effects can be achieved.

The essential details of the spring elements are described on the basis of the representation of the spring element 30 in FIG. This spring element 30 is a spring element in the manner of a clip, which is independent in terms of manufacture, and which is used in the assembly of the lock in the lower cap 25, which has a corresponding profiling for this purpose, namely a holding rib 36, a supporting rib 37 and the Correspondingly wide ramp 28. The spring element 30 effectively fits into the space formed by these parts of the lower cap 25. In terms of shape, it is composed of the inner S-arm 38 and the outer S-arm 39, an undercut holding attachment 40 for enclosing the holding rib 36 adjoining the inner arm 38, while the outer arm 39 has a supporting extension 41 which opposes one another the support rib 37 sets. The curvature of the inner arch 38 also bears against the supporting rib 37. The part of the outer arch 39 which is directed inwards towards the ramp 28 has an inner surface 48 as a reference surface, and the part which is directed outwards is reinforced and has a groove 42 on the outside which is conical in cross section and into which the associated inclined edge 34 of the base part is located 35 of the inserted lock tongue 12, whereby centering and fixing the position of the lock tongue in the direction transverse to its main plane. This eliminates the possibility of vibratory movements in this direction, so that no related noises can be caused.

When the lock tongue 12 is inserted into the opening 18 according to arrow 29, the inclined edges 34 each press against the deepest of the relevant groove 42, and as a result the spring element 30 is tensioned, i. H. the S-shape of the spring element is reduced in the direction of insertion or the S-bends are narrowed (compressed). A broadening of the outer outline of the S-shape of the spring element does not take place in this way, however, because the deflection movement of the spring element 30 is predetermined by the profiling of the lower cap 25 - support rib 37 on the one hand and ramp 28 on the other - and the central strand 43 between the two S-arches 38, 39 is forced to assume a flat S-shape. The extension 41 slides along the support rib 37 in the direction of the arrow 29 until it almost abuts the inner arch 38.

While a spring element independent of the lower cap 25 is shown in FIG. 3, two spring elements 31 are shown in FIG. 2, which are integrally formed on the lower cap 25, but have essentially the same design as the independent spring element 30. FIG. 2 consists of two Different halves visible on both sides of the dash-dotted longitudinal center line of the castle, designated A and B. These halves differ both by slightly different designs of the S-shapes of the spring elements 31 and, in particular, by different contours of the respective lock tongues 12. While the lock tongue according to half A of the figure following the oblique edge 34 via a larger rounding directly into the base part 35 merges, a step 44 follows the inclined edge 34 according to half B before the full width of the base part 35 is reached. These different contours of the bilateral lock tongues also require different designs of the lower cap 25 which ends the support rib 37 according to half A at the level of the outer S-bend 39 of the spring element 31, while on the side of the B half the support rib 37 advances towards the insertion opening 18 and there bends a little inward so that an edge piece 45 results. These differences A and B show that the spring elements can be used with different lock tongues.

The lock shown in Figure 2 is one with a U-shaped lock housing 10, i. H. the lower lock plate is bent upwards in a U-shape on its longitudinal edges, so that upstanding legs 46 result, between which the upper lock plate, not shown in FIG. 2, is mounted like a cover. In this conventional embodiment, the front part 32 of the lock tongue 12 is not only guided in the path 11 above and below, but also on the side edges 33 by means of the legs 46. However, there is the above-mentioned play leading to noise between the related components. To compensate and thus to avoid noise, the spring elements 31 are provided, which can move resiliently in the corresponding recesses 47 of the lower cap 25 in the longitudinal direction of the lock. The boundaries of the recesses 47 towards the insertion opening 16 are indicated by dashed lines in FIG. It also follows that the spring elements 31 are compressed in the locked state of the lock shown in the longitudinal axis direction, to the extent that the respective inner S-arm 38 touches the associated surface of the retaining rib 36 and is supported thereon. As a result, the characteristic of the spring element 31 in question changes in such a way that the person can feel it clearly when the lock tongue 12 is inserted. There are numerous design options in the area of the two S-bends 38, 39 in order to achieve this effect. The characteristic of the spring elements should reach a maximum pressure force when plugged in, when the arch 38 is supported, and then only require a reduced pressure force until the moment the locking member 14 snaps into the opening 13, which can feel the snapping into place.

It can be seen from FIG. 2 that the spring elements 31, with their surfaces directed towards the center of the lock, bear against the side edges 33 of the lock tongue 12 and thereby position them. The clear width between the mentioned inner surfaces 48 of the spring elements 31 is smaller than the clear width between the inner surfaces of the legs 46, but not smaller than the width of the front part 32 of the lock tongue 12. In this embodiment, those which become effective when the lock tongue is inserted Friction coefficients are kept particularly low, but it can also be provided that the clear width between the inner surfaces 48 is a little smaller than the width of the tongue part 32. The tarnishing of the tongue 12 with its oblique edges 34 during insertion into the respective outer arches 39 with conical grooves 42 additionally center the lock tongue and prevent it from tilting.

The spring elements shown in FIG. 4 correspond as such to the spring elements 30 according to FIG. 3, but here they are firmly connected to one another by a connecting web 49. It is therefore a one-piece plastic injection molded part, which is inserted into the lower cap 25 during assembly of the lock and thus simplifies production.

Claims (19)

1. Buckle for safety belts in passenger carrying vehicles, including a housing (10) and a tongue (12) which can be inserted into an insertion opening (18) thereof and can be locked in said housing (10) by at least one latching member (14) and is acted upon by a spring-loaded ejector (22), characterised in that an approximately S-shaped spring element (30,31) is disposed in said housing (10) at each of the two narrow sides of the insertion opening (18) for the tongue (12) in addition to said latching member (14), said spring elements (30,31) projecting laterally with an abutment surface (42,48) into the path (11) which the tongue (12) must traverse upon its insertion, with the S-path being disposed in the plane of said buckle tongue (12) or parallel thereto and the upper S-curve acting upon the tongue (12), at its respective side extending at an angle to the longitudinal axis thereof, with respective force components counter to and transverse to the direction of insertion, and in that the curve of the S-shape of the spring element (30,31) which comes into contact with the tongue (12) straightens out and is provided with an outwardly open groove (42) for receiving the edge of the buckle tongue.

2. Buckle according to claim 1, characterised in that said spring elements (30, 31 ) are disposed symmetrically relative to said central longitudinal axis of said housing means (10) and/or said path (11) thereof for said buckle tongue (12) and are disposed in an appropriate mirror-inverted manner.

3. Buckle according to claim 1 or 2, characterised in that with reference to the location at which said latching member (14) engages said buckle tongue (12), each of said spring elements (30, 31) is disposed in said housing means (10) in such a way that an inserted tongue (12) comes into contact with said spring elements shortly before it reaches this location, and when it does reach this location, it stresses said spring elements and is thus itself under prestress.

4. Buckle according to one of the claims 1 - 3, characterised in that said groove (42) of said spring element (30, 31) has a trapezoidal cross section which widens in the direction toward said insertion opening (18) of said housing means (10).

5. Buckle according to one of the claims 1-4, in which each S-shaped spring element (30, 31) is band-like and has a flat, rectangular crosssection; the inner space of said insertion opening (18) of said housing means (10) is closed off toward the side by one of said spring elements (30, 31).

6. Buckle according to claim 5, characterised in that the end of said S-shaped spring element (30, 31 ) closest to said insertion opening (18) of said housing means (10) continues via a flange-like extension (41) which is bent toward the interior of said housing means (10) away from said insertion opening (18) thereof.

7. Buckle according to claim 6, characterised in that said flange-like extension (41) is formed on said spring element (30, 31) at such an angle that the closure of said insertion opening (18) of said housing means (10) is effected with prestress at the affected side via said spring element (30, 31).

8. Buckle according to one of the claims 1 - 7, characterised in that the end of said S-shaped spring element (30, 31) remote from said insertion opening (18) of said housing means (10) is provided with a further extension (40) which serves as an abutment surface for further parts of said housing means (10).

9. Buckle according to claim 8, characterised in that said housing means (10) is provided with a holding rib (36), and that said further extension (40) of said spring element (30, 31) embraces said holding rib (36) and fixes the position of said spring element (30, 31) in said housing means (10).

10. Buckle according to one of the claims 1 - 9, characterised in that the shape of said spring elements (30, 31), with reference to the curvature, length, build-up of material, and/or spacing from adjacent parts of said housing means (10) with which they come into contact when they are displaced, is such that during insertion of said buckle tongue (12), and during its progress up to the moment of engagement, the spring forces change, and in particular are reduced prior to engagement to such an extent that a person putting on the buckle can distinctly feel the engagement.

11. Buckle according to one of the claims 1 - 10, characterised in that said spring elements (30, 31) and the acted-upon components are coordinated in such a way thath the clamping forces of said spring elements (30, 31, 50) are immediately eliminated when said buckle tongue (12) is released.

12. Buckle according to one of the claims 1 -11, characterised in that said spring elements (30, 31) are molded parts of synthetic material.

13. Buckle according to claim 12, characterised in that said spring elements (30, 31) are independent components which are placed in said housing means (10).

14. Buckle according to claim 12, characterised in that said spring elements (30, 31) are integrally formed on components of said housing means (10).

15. Buckle according to claim 12 or 13, characterised in that two spring elements (30, 31) are connected into a unit by means of a connecting element (49), with said unit being placed in said housing means (10), where it is fixed by the shape of the latter.

16. Buckle according to one of the claims 13 or 15, characterised in that said spring elements (30, 31) are in the form of clips, and in which said housing means (10) includes an appropriately shaped part which is intended for the insertion of said spring elements (30, 31).

17. Buckle according to one of the claims 1 - 16, characterised in that said housing means (10) especially the bottom cover (25), includes pocket-like recesses (47) for receiving said spring elements (30, 31).

18. Buckle according to one of the claims 1 - 17, characterised in that a spring element (30, 31) is diposed on both sides of said insertion opening (18) in such a way that the inside width between the inwardly directed surfaces of said spring elements (30, 31), which surfaces delimit said path (11) for said buckle tongue (12), on the one hand is less than the inside width of said path (11), and on the other hand is at least as great as the width of that portion of said tongue (12) which enters said path (11).

19. Buckle according to one of the claims 1 - 17, characterised in that the inside width between inwardly directed surfaces of said spring elements (30,31) is less than the width of that portion of said buckle tongue (12) which enters said path (11) of said housing means (10) therefor.

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