EP0129248B1 - Safety belt buckle - Google Patents

Description

The invention relates to a lock for seat belts in the center of passenger transport, with a lock housing and a lock tongue which can be inserted into an opening and locked by at least one locking member in the housing and is acted upon by a spring-loaded ejector.

Belt buckles of this type are known for example from DE-AS-2 160 089, US-PS-3 807 000 and DE-GM-7 438 663 and 7 525 646. All these buckles have in common that rattling noises occur when driving over bumps and due to vibrations in the drive area of the motor vehicle, aircraft or the like, which are caused by the fact that the metallic lock tongue in the lock housing can make small movements. Attempts have already been made to dampen these noises by partially sheathing the lock tongue with plastic and / or by producing certain plastic housing parts (DE-OS-3 128 139), but there is also a margin between the lock housing for constructional and technical reasons and inserted tongue, so that the movements mentioned are not excluded and there is always rattling. This affects the driving comfort.

The invention has for its object to provide a lock for seat belts in passenger transportation, especially motor vehicles, in which such rattling noises can no longer arise. 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 has the advantage that not only the rattling noises mentioned are excluded, but there is also an additional guidance and fixation of the lock tongue in the housing when inserted, in the locked state and when the lock is opened.

The lock tongue is guided and fixed in the housing during the locking and unlocking process by spring elements inserted or incorporated into the lock housing, whereby these can be designed differently in that they have one or more force components transverse to the direction of insertion or ejection of the lock tongue.

For example, forces can be applied by means of the individual embodiments described in the subclaims, which act essentially perpendicular to the narrow lateral surfaces of the lock tongue, but moreover the spring elements can also be arranged such that the lock tongue also has a force component acting against the direction of insertion of the lock tongue is applied.

In a further embodiment of the invention it is provided that the spring elements have sections which protrude into the insertion path of the lock tongue, in such a way that the lock tongue slides over these sections when inserted, in such a way that they are essentially perpendicular to theirs Main surfaces directed force component is applied. This is preferably achieved in that the sections are equipped with corresponding surfaces rising in the direction of insertion of the lock tongue.

Of course, the spring elements can also be designed according to the invention in such a way that different force components running transversely to the direction of insertion or ejection of the lock tongue are applied.

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,
• Fig. 5 ein weiteres Ausführungsbeispiel eines erfindungsgemäßen Schlosses in Grundriß-Ansicht.

In the drawing, 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 both sides of the longitudinal center line,
• 3 shows a spring element in a diagrammatic representation,
• 4 two spring elements connected by a web as an independent installation part,
• Fig. 5 shows another embodiment of a lock according to the invention in plan view.

The conventionally constructed belt 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 an orthogonal to the lock housing plates 10 and Lock tongue 12 arranged locking member 14 can snap to close the buckle. To disengage 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 is movable with play in the housing for reasons of manufacture and ease of use, rattling noises occur again and again when the seatbelt buckle is closed, especially when the road is uneven 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.

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 aforementioned play between the relevant components of the castle by touching, guiding and centering the 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 clear when plugging in when the engagement takes place. This largely eliminates the need to listen 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 have 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.

Based on the representation of the spring element 30 in an enlarged scale Figure 3 describes the essential details of the spring elements. This spring element 30 is a spring element that is independent of manufacture in the manner of a clip, which is used in the assembly of the lock in the lower cap 25, which has a corresponding profiling for this purpose, namely a retaining rib 36, a support 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-arch 38 and the outer S-arch 39, an undercut holding attachment 40 for enclosing the holding rib 36 adjoining the inner arch 38, while the outer arch 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 on the outside a groove 42 which is conical in cross section and into which the associated inclined edge 34 of the Base part 35 of the inserted lock tongue 12 sets, 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 in turn is forced to adopt 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 lock tongues on both sides also require different designs of the lower cap 25, in which the support rib 37 ends according to half A at the level of the outer S-curve 39 of the spring element 31, while on the side of the B half the support rib 37 extends towards the insertion opening 18 advances 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 its longitudinal axis direction, to the extent that the 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 inserted, if 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.

From Figure 2 it can be seen that the Spring elements 31, with their surfaces facing 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.

FIG. 5 shows a further exemplary embodiment of a lock according to the invention, in which the spring elements 50 have a different shape than the exemplary embodiments described above and in particular also require a different introduction and transfer of force to the lock tongue.

Each spring element 50 has an arcuate upper part 50a and an adjoining web 54 which extends essentially along the lock. The spring elements 50 each protrude with lateral sections 51 into the path 11 of the lock tongue 12. The sections 51 are arranged in pocket-shaped recesses 56 in the lower cap 25 of the lock housing 10. The sections 51 have a slope that rises in the direction of insertion of the lock tongue 12 in order to press the lock tongue upwards when it is inserted and thus to be able to fix it.

The free end of the upper part 50a of the spring elements 50 is also provided with an incline as an insert 52. The ramp-shaped lugs 52 cooperate with wedge-shaped lugs 53 on the front lower edge of the push button 15.

The spring elements 50 continue in webs 54, which are arranged essentially parallel to one another in the longitudinal direction of the lock, via a section 50b bent toward the lateral outer surfaces of the lock. The webs 54 can be referred to as resilient guideways, since on the one hand they introduce the clamping forces to be described in more detail into the lock housing 10, but on the other hand their extensions serve as guide sections 55 for lateral limitation and guiding of the ejector 22. It is important that the guide portions 55 are resilient, so that the ejector 22 he can be performed freely. By a corresponding change in the supporting cross section of the guide sections 55 it can be achieved that the spring action is low in the largest area of the ejector stroke and is only increased in the area of the latching point of the lock tongue. This enables a particularly easy and inexpensive handling of the lock as a whole. In this regard, the positioning of the front end 50a of the spring elements 50 can also be used.

The functioning of the spring elements 50 in the exemplary embodiment according to FIG. 5 is now as follows.

If the lock tongue 12 is inserted into the lock housing 10 via the insertion funnel 18, it first runs with its front end 32 onto the sections 51 of the spring elements 50 and is guided upwards. As a result, the lock tongue is guided for the first time. As soon as the lock tongue 12 is pushed so far that the locking member 14 engages in the recess 13 of the lock tongue 12, the push button 15 is also pivoted into its front end position, the wedge-shaped projections 53 of the push button 15 pressing onto the ramp-shaped projections 52 of the spring elements 50 and cause a movement of the arcuate portion 50a of the spring elements 50 in the direction of the lock tongue 12. The lateral pressure surfaces 57 of the spring elements 50 are pressed against the lock tongue 12 and clamp them firmly. The clamping forces themselves are then introduced into the lock housing 10 via the webs 54 arranged parallel to the longitudinal axis of the lock. In this front position of the lock tongue 12, however, it has also been pushed up so far along the sections 51 that it is fixed in the direction perpendicular to its main surfaces between the sections 51 and the upper housing parts.

By appropriate design of the lateral pressure surfaces 57, as described in detail with reference to the above exemplary embodiments, a partially form-fitting encirclement of the lock tongue 12 can be achieved, as a result of which the guidance and fixing of the lock tongue 12 is further improved.

It is essential that the clamping forces of the spring elements 50 are only triggered in the area of the latching point of the lock tongue 12 in order to achieve the lowest possible insertion forces. This also has the advantage that the clamping forces of the spring elements 50 are released during the unlocking process of the lock tongue 12 before the lock tongue 12 is ejected via the ejector 22, which ensures a safe ejection of the lock tongue 12.

This easy handling and high functional reliability is achieved in the exemplary embodiment according to FIG. 5 in particular also by the corresponding configuration of the lugs 52, 53.

In an embodiment according to the invention it is prevented that a self-locking occurs between the shoulders 52, 53 and the spring elements 50 could thereby laterally deflect when the lock tongue 12 is inserted.

Moreover, the advantages described with reference to the other exemplary embodiments can also be realized in this exemplary embodiment according to FIG. 5 by appropriate design adaptation.

The features of the subject matter of these documents disclosed in the above description, the patent claims, the drawing and the summary can be essential both individually and in any combination with one another for realizing the invention in its various embodiments.

Claims (30)

1. Buckle for safety belts in passenger carrying vehicles, including a housing means (10) and a tongue (12) which can be inserted into an insertion opening (18) and can be locked in said housing means (10) by at least one latching member (14) and is acted upon by a springloaded ejector (22) characterised in that at least one spring element (30, 31, 50) is disposed in said housing means (10) in the vicinity of said insertion opening (18) for said tongue (12) in addition to said latching member (14); each of said spring elements (30, 31, 50) has at least one abutment surface (48) which projects into the path (11), which said tongue (12) must traverse upon its insertion, laterally in such a way that the tongue (12) is acted upon transverse to its direction of insertion or ejection.

2. Buckle according to claim 1, characterised in that said insertion opening (18) of said housing means (10) for said buckle tongue (12) has two narrow sides, with a respective spring element (30, 31,50) being disposed at each of said narrow sides.

3. Buckle according to claim 1 or 2, characterised in that said spring elements (30, 31, 50) 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.

4. Buckle according to one of the claims 1 - 3, 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, 50) 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.

5. Buckle according to one of the claims 1 - 4, characterised in that said spring elements (30, 31, 50) are shaped in such a way, and/or disposed in said housing means (10) in such a way, that they act upon an inserted buckle tongue (12) with a force component which is essentially directed at right angles to narrow lateral surfaces of said tongue.

6. Buckle according to one of the claims 1 - 5, characterised in that said spring elements (30, 31, 50) are shaped in such a way, and/or are disposed in said housing means (10) in such a way, that they act upon an inserted buckle tongue (12) with a force component which acts counter to the direction of insertion of said tongue (12).

7. Buckle according to one of the claims 1 - 6, characterised in that each of said spring elements (30, 31) has an approximately S-shape, with the S-path being disposed in or parallel to the plane of said buckle tongue and the outer S-curve acts upon the affected sides of said buckle tongue (12) with respective force components counter to and transverse to the direction of insertion.

8. Buckle according to claim 7, characterised in that said outer S-curve of each spring elements (30, 31) has a portion which extends straight and is provided with a groove (42) which is directed toward said insertion opening (18) of said housing means (10) for receiving an edge of a buckle tongue (12).

9. Buckle according to claim 8, 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).

10. Buckle according to one of the claims 7 - 9, 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).

11. Buckle according to claim 10, 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.

12. Buckle according to claim 11, 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 sides via said spring element (30, 31).

13. Buckle according to one of the claims 7 - 12, 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).

14. Buckle according to claim 13, 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).

15. Buckle according to one of the claims 1 - 14, characterised in that each of said spring elements (30, 31), at a location thereof which is adapted to contact said buckle tongue (12), has a configuration which provides for overlap of said tongue (12) and fixes the position of the latter essentially at right angles to the plane of said tongue.

16. Buckle according to one of the claims 1 - 15, characterised in that said spring elements (30, 31, 50) are shaped in such a way, and/or are disposed in said housing means (10) in such a way, that they act upon an inserted buckle tongue (12) with a force component which is essentially directed at right angles to the main surfaces of said tongue (12).

17. Buckle according to claim 16, characterised in that said spring elements (50) are provided with a portion (51) which projects into said insertion path (11) for said buckle tongue (12) and which is provided with a surface which rises toward the exterior of said buckle.

18. Buckle according to one of the claims 1 - 17, characterised in that the buckle includes a push button (15) for releasing said latching member (14) from said buckle tongue (12); said push button (15) is provided with projections (53); and that said spring elements (50) are provided with respective ramp-like extensions (52) which are adapted to positively connect with said projections (53) of said push button (15) in the latched state of said buckle; said projections (53) stress said ramp-like extensions (52) in the direction toward said buckle tongue (12), and thereby securely hold the latter.

19. Buckle according to claim 18, characterised in that each of said spring elements (50) is provided with means (54) for transferring clamping forces into said housing means (10).

20. Buckle according to claim 19, characterised in that said means (54) essentially extends in said housing means (10) in the longitudinal direction of said buckle and is provided with a portion (55) for laterally guiding said ejector (22).

21. Buckle according to one of the claims 1 - 20, characterised in that the shape of said spring elements (30, 31, 50), 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.

22. Buckle according to one of the claims 1 - 21, characterised in that said spring elements (30, 31, 50) 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.

23. Buckle according to one of the claims 1 - 22, characterised in that said spring elements (30, 31, 50) are molded parts of synthetic material.

24. Buckle according to claim 23, characterised in that said spring elements (30, 31, 50) are independent components which are placed in said housing means (10).

25. Buckle according to claim 23, characterised in that said spring elements (30, 31, 50) are integrally formed on components of said housing means (10).

26. Buckle according to claim 23 or 24, characterised in that two spring elements (30, 31, 50) 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.

27. Buckle according to one of the claims 1 - 26, characterised in that said spring elements (30, 31, 52) 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, 50).

28. Buckle according to one of the claims 1 - 27, characterised in that said housing means (10) especially the bottom cover (25), includes pocket- like recesses (47) for receiving said spring elements (30, 31, 50).

29. Buckle according to one of the claims 1 - 28, characterised in that a spring element (30, 31, 50) is disposed 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, 50), 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).

30. Buckle according to one of the claims 1 - 28, characterised in that the inside width between inwardly directed surfaces of said spring elements (30, 31, 50) 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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