DE29910720U1 - Locking device for an adjustable vehicle seat - Google Patents

Description

Brose Automotive Parts GmbH & Co.,
Limited partnership, Coburg
Ketschendorfer Strasse 38-50

9 64 50 Coburg

BRO715

Locking device for an adjustable vehicle seat

Description

The invention relates to a locking device for an adjustable vehicle seat according to the preamble of patent claim 1.

Such a locking device serves to lock an adjustment position of two seat elements of a vehicle seat that are movable relative to one another, which has previously been reached by means of a suitable adjustment device. The adjustment device can in particular be a longitudinal rail guide for adjusting the seat position in the longitudinal direction of the vehicle, with one rail of the longitudinal rail guide being connected to the locking rail and the other rail to the

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The longitudinal rail guide is connected to the locking unit of the locking device. However, the locking device can also be used to lock other adjustment devices with two components that can be moved relative to one another, in particular that can be displaced relative to one another.

EP 0 408 932 B1 discloses a locking device for a vehicle seat with a locking rail running parallel to an adjustment direction, which has periodically arranged notches and locking openings, and with a locking unit assigned to the locking rail. The locking unit comprises several locking teeth that can be moved independently of one another in a locking direction, are elastically preloaded in the locking direction and can be disengaged together, each of which has two straight lateral flanks intended to rest on the notches. At least one of the two lateral flanks runs at an acute angle to the locking direction, which is chosen to be so small that the locking tooth cannot be automatically pushed out of its locking position if the vehicle seat is loaded in the adjustment direction in an accident (self-locking); and the locking teeth are designed and arranged in such a way that a stepless locking of the locking device is possible and that when the locking device is locked, at least two locking teeth rest with their flanks on one of the catches in opposite directions (with respect to the setting direction). Depending on the design of the locking device, these two locking teeth can be assigned to the same locking rail or to two different locking rails.

So that in the locked state, two or more flanks of this locking device are actually always supported in opposite directions on one notch each (and thus

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enable reliable locking along the adjustment direction), either the device must be manufactured with extremely low tolerances, or the projection of the oblique flanks of the locking teeth onto the adjustment direction must be sufficiently large so that, despite tolerances occurring in the individual components of the locking device, at least two locking teeth always engage in locking openings and rest against a notch with oppositely oriented flanks. In the first case, the problem is that minimizing the tolerances involves a great deal of effort and correspondingly high costs. In the second case, the problem is that if the acute angle of the oblique flanks is chosen sufficiently small (absolutely necessary with regard to crash safety), the locking teeth must have a very large extension in the longitudinal direction so that the projection of the oblique flanks onto the adjustment direction is large enough to compensate for the tolerances of the locking device.

The invention is therefore based on the object of creating a locking device of the type mentioned at the beginning, which enables a reliable compensation of the tolerances occurring in the locking device with the least possible effort and with a small space requirement, so that two locking teeth are always supported on a catch in opposite directions.

This object is achieved according to the invention by creating a locking device with the features of patent claim 1.

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According to this, the locking teeth each have an insertion bevel at their ends facing the locking rail, on which the locking tooth intended for locking can slide into a locking opening, and the locking teeth are mounted in such a way that the respective locking tooth can move transversely to the locking direction when it slides on the insertion bevel into the catch.

Since the insertion bevels are only used to insert the locking teeth into the locking openings and not to permanently support the locking teeth on one of the notches, the insertion bevels can have a considerably larger angle with respect to the locking direction of the locking teeth than the slanted flanks of the locking teeth intended to rest on one of the notches. Thus, the insertion bevels can have a comparatively large projection on the adjustment direction even if they only extend slightly along the locking direction.

The desired tolerance compensation can be achieved as follows: If, due to tolerances, a locking tooth, which is intended to rest on one of the catches in the locked state, does not come into contact with the corresponding catch with its lateral flank intended for this purpose, but with its insertion bevel, then this locking tooth slides further into the corresponding catch opening on the insertion bevel until it rests against the catch with its flank intended for this purpose. For this purpose, the locking teeth are guided in the locking direction in such a way that they can move transversely to the locking direction (and thus essentially in the adjustment direction) when they slide into a catch opening on their insertion bevel.

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It is already known from DE 27 13 973 A1 to provide the locking teeth of a locking device for motor vehicle seats with an insertion bevel; however, this is a locking device in which the locking teeth are arranged at a distance from one another that corresponds to the period of the catches and locking openings. The idea of the present invention, on the other hand, is to design a locking device with locking teeth arranged at a different distance from the period of the catches and locking openings in such a way that both tolerance compensation and secure locking are achieved with little effort and in a small space. This is achieved here by combining the insertion bevels with the mobility of the locking teeth transverse to the locking direction (i.e. in the adjustment direction).

The locking teeth are preferably mounted so that they can move in such a way that the movement of the locking teeth transversely to the locking direction is possible without a corresponding movement of the adjustment part connected to the locking unit (e.g. the rail of a seat longitudinal adjustment) or of the other locking teeth.

This can be achieved, for example, by the locking teeth being mounted individually so that they can be tilted (slightly pivoted) in the plane defined by the locking and adjustment directions or by being slightly displaceable in this plane along the adjustment direction so that the adjustment part connected to the locking unit or the other locking teeth are not moved.

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Furthermore, the width of the locking openings in the adjustment direction is larger than the projection of the locking teeth in this direction in order to enable the mobility of the locking teeth along the adjustment direction.

In a preferred embodiment of the invention, each locking tooth has two oblique flanks, which are each intended to engage with different sides of a catch (in opposite directions) and which are each adjoined by an insertion bevel towards the catch rail.

In order to ensure that, when the locking device is in the locked state, two locking teeth are always supported on one notch in opposite directions, each oblique flank of a locking tooth can be assigned an oblique flank of another locking tooth, whereby the shortest distance between the two flanks along the adjustment direction is, on the one hand, less than or equal to an integer multiple of the period of the notches minus the width of a notch opening and, on the other hand, greater than or equal to the aforementioned multiple of the period minus the width of a notch opening and minus the sum of the projections of an oblique flank and an insertion bevel on the adjustment direction.

This can be achieved in a particularly simple manner in that the shortest distance between opposing slanted flanks of adjacent locking teeth is, on the one hand, smaller than or equal to the width of a notch and, on the other hand, greater than or equal to the width of a notch minus the sum of the projections of a slanted flank and an introduction bevel on the adjustment direction.

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The acute angle of the beveled flanks with respect to the locking direction is preferably less than 10° and is in particular between 3° and 5°. The angle of the insertion bevels with respect to the locking direction, on the other hand, does not lead to self-locking and is preferably between 30° and 60°, in particular around 45°.

The length and angle of the lead-in chamfers are selected such that the extension of the lead-in chamfer projections on the adjustment direction is just large enough to reliably compensate for the tolerances of the components of the locking device in the adjustment direction.

Further advantages of the invention will become clear from the following description of an embodiment with reference to the figures.

Show it:

Figure 1 - a longitudinal section through a locking device with a locking rail and a locking unit assigned to the locking rail;

Figure 2 - a section of a locking device with a locking rail and a locking unit assigned to the locking rail, whereby a locking tooth with an insertion bevel hits a notch of the locking rail;

Figure 3 - a section of a locking device according to Figure 2, wherein a locking tooth with an inclined flank rests directly on a catch of the locking rail.

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The locking device shown in Figure 1 comprises a locking rail 10, which is assigned, for example, to the lower rail of a seat longitudinal adjustment and is firmly connected thereto, as well as a locking unit 1, which is assigned, for example, to the upper rail of a seat longitudinal adjustment and is firmly connected thereto.

The locking rail 10 comprises a plurality of notches 11 of width b and locking openings 12 of width a arranged periodically at a period dimension P along the adjustment direction E of the seat longitudinal guide.

The locking unit 1 arranged above the locking rail 10 comprises a plurality of locking teeth 2, 3, 4, 5 arranged in a housing 6, which are assigned to the locking openings 12 of the locking rail 10 and which are spring-loaded in the direction of the locking openings 12 (along the locking direction R) by springs 27 mounted on corresponding receptacles 7 of the housing 6. The locking teeth 2 to 5 each comprise a cylindrical base body 25 (of diameter d) which is movably guided in a guide channel 9 (see Figures 2 and 3) of a guide 8 of the locking unit 1 in the locking direction R and to which a collar 26 is connected towards the respective spring 27, which forms a stop for the spring 27.

At their ends facing the locking rail 10, the locking teeth 2 to 5 each taper conically towards the locking rail 10 and thereby form two flanks 23, 24 in the plane spanned by the adjustment direction E and the locking direction R, which run at an acute angle x/2 obliquely to the locking direction R.

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The locking teeth 2 to 5 are arranged at a constant distance from one another in such a way that the distance m of the central axes M of adjacent locking teeth 2, 3 or 3, 4 or 4, 5 is smaller than the period P of the notches and locking openings. More details on the arrangement of the locking teeth 2 to 5, which is selected in such a way that in the locking state of the locking device there are always exactly two (or more generally at least two) locking teeth supported in opposite directions (with respect to the adjustment direction E) on one of the notches 11, will be explained below using Figures 2 and 3.

In the locking state shown in Figure 1, two adjacent locking teeth 4, 5 with opposing flanks 24 and 23 are supported in opposite directions on one of the catches 11 of the locking rail 10. As a result, the locking unit 1 can no longer be moved along the adjustment direction E relative to the locking rail 10, so that the lower rail assigned to the locking rail 10 and the upper rail of the longitudinal rail guide assigned to the locking unit 1 are locked together in a defined position without play.

The angle of inclination x/2, at which the flanks 23, 24 each run at an acute angle with respect to the locking direction R, is selected such that the locking teeth 4, 5 cannot be pushed out of the associated locking openings 12 by crash-related, very large forces acting along the adjustment direction E; self-locking therefore exists.

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By means of a release device which is concealed in Figure 1 by the locking teeth 2 to 5 and the associated compression springs 2 7 and therefore cannot be seen in detail, the locking teeth can be released together from the locking openings 12 of the locking rail 10.

Figures 2 and 3 show an example of a section of a locking device according to Figure 1, in which in particular two locking teeth 2, 3 and the section of the locking rail 10 located directly under these locking teeth 2, 3 are shown in more detail. However, the locking device is shown here in a different state than in Figure 1; because in this case the two left locking teeth 2, 3 of the locking unit are each intended to engage in a locking opening 12, while in Figure 1 this is the case with the two right locking teeth 4, 5.

In Figures 2 and 3, the same reference symbols are used for corresponding components as in Figure 1, so that a more detailed explanation of those components that have already been described in detail using Figure 1 can be omitted here. Furthermore, for the sake of clarity, some reference symbols have only been entered in one of Figures 2 and 3. Since these figures show one and the same section of a locking device at two different times, these reference symbols should apply to both figures.

Based on the detailed representation in Figures 2 and 3, it is particularly clear that the locking teeth 2, 3 have insertion bevels 21, 22 at their ends facing the locking rail 10, which are formed by an additional conical taper of the locking teeth 2, 3 in the area adjacent to the beveled flanks 23, 24. The additional

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Before the conical taper, two insertion bevels 21, 22 are formed on the locking teeth 2, 3 in the plane spanned by the adjustment direction E and the locking direction R, each of which runs at an angle y/2 (see Figure 3) of approximately 45° to the locking direction R.

These insertion bevels, the significance of which will now be explained in more detail using Figure 2, are not shown in the overview in Figure 1 for the sake of simplicity.

In the state of the locking device shown in Figure 2, a locking tooth 2 has completely penetrated into a locking opening 12, so that this locking tooth 2 does not rest on the locking device 11 with its oblique flank 24 assigned to the next locking device 11, but with its section adjoining this flank 24 at the top and running parallel to the locking direction R. In this state, the other (neighboring) locking tooth 3 with its oblique flank 23, which is opposite the aforementioned flank 24 of the first locking tooth 2, should now rest on the locking device 11 in the opposite direction, so that the locking device is reliably locked and free of play. Due to tolerances of the locking device, for example with regard to the distance m of the center axes M of the locking teeth 2, 3, with regard to the width b of the notches 11, with regard to the diameter d of the base body 25 of the notches 2, 3 or with regard to the acute angle x/2 at which the oblique flanks 23, 24 are inclined to the locking direction R, the second locking tooth 3 does not rest with its oblique flank 23 facing the first locking tooth 2, but with its adjoining insertion bevel 21 on the notch 11 located between the two locking teeth 2, 3.

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Since the locking tooth 3, which rests on the catch 11 with an insertion bevel 21 (as shown in Figure 1), is preloaded by a spring 27 in the locking direction R, it slides with its insertion bevel 21 over the edge of the catch 11 and thus further into the locking opening 12. In the process, the locking tooth 3, which is guided with sufficient play in a channel 9 of the guide 8, tilts in the plane spanned by the adjustment direction E and the locking direction R, as can be seen from Figure 3 in comparison with Figure 2.

Figure 3 shows the state of the locking device after the locking tooth 3, which initially rests against a catch 11 with an insertion bevel 21, has penetrated into the locking opening 12 so far that it rests against the catch 11 with an inclined flank 23. The current center axis M' of the locking tooth 3 is slightly inclined compared to the original center axis M (which runs parallel to the locking direction R). This means that both locking teeth 2, 3 now rest against a catch 11 of the locking rail 10, in opposite directions. The locking device thus reliably prevents any movement along the adjustment direction E.

However, in the state shown in Figure 3, in the event of a crash, the crash forces are particularly applied to the locking tooth 2 that is fully inserted into a locking opening, while the other locking tooth 3 can only absorb comparatively small crash forces. Therefore, either the locking teeth 2 to 5 should be dimensioned in such a way that a single (fully engaged) locking tooth is sufficient to transmit the forces that occur in the event of a crash, or the locking teeth 2 to 5 must be positioned so far along the

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The locking tooth 27 must be displaceable in the direction of adjustment and the spring force of the springs 27 must be dimensioned such that, in the configuration shown in Figures 2 and 3, the second locking tooth 3 can be pushed into a locking opening 12 at least so far that its flank 23 resting against a locking element 11 covers this locking element 11 along its entire height (in the direction of insertion R).

A look at Figure 2 shows that the two locking teeth 2, 3 can penetrate together into one of the locking openings 12 and can thereby be supported in opposite directions on a notch 11 if the shortest distance k between the oppositely located oblique flanks 24 and 23 of the locking teeth 2, 3 is on the one hand smaller than the width b of the notch 11 and on the other hand larger than the width b minus the sum e + f of the projections of an oblique flank and an insertion bevel on the adjustment direction E.

The two locking teeth, each of which rests with a flank in opposite directions on a notch of the locking rail, do not necessarily have to be adjacent locking teeth. Rather, the general condition applies that the shortest distance between the opposing, diagonally running flanks of these two notches must, on the one hand, be less than or equal to an integer multiple of the period dimension P minus the width a of a locking opening 12 and, on the other hand, greater than or equal to the aforementioned multiple of the period dimension P minus the width a of a locking opening 12 and minus the extension e + f of the sum of the projections of a diagonal flank 23 or 24 and an insertion bevel 21 or 22 onto the adjustment direction E.

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Furthermore, Figures 2 and 3 show that both locking teeth 2, 3 do not have to rest on the corresponding catch 11 with one of the slanted flanks 23 or 24. Rather, one of the locking teeth 2, 3 can be completely penetrated into the associated catch opening 12, so that it does not rest on the corresponding catch 11 with a slanted flank, but rather with an adjoining surface section running parallel to the locking direction R. The diameter d of the locking tooth 12 in the area of this surface section corresponds to the largest diameter of the locking tooth in the area of its slanted flanks. The locking state described last is considered to be particularly advantageous because it achieves a particularly stable locking of the locking device.

The particular advantage of the arrangement described in Figures 2 and 3 and in particular of the insertion bevels 21, 22 of the locking teeth 2, 3 is that the tolerances of the locking device along the adjustment direction E can be compensated for by a suitable design of the insertion bevels 21, 22, in particular with regard to the size of the projection f of the insertion bevels on the adjustment direction E. This is achieved with a comparatively small space requirement, since due to the large angle of inclination y/2 of the insertion bevels 21, 22, they have a comparatively large extension f of their projections on the adjustment direction E (compared to the oblique flanks 23, 24) with only a small extension along the locking direction R.

In other words, the so-called mirror width s of the locking teeth 2, 3, i.e. their diameter at their free end, is increased by the insertion bevels 21, 22.

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lignitely reduced. However, the smaller the mirror width s, the greater the tolerances that can be permitted without affecting the function of the locking device. This is because a joint engagement of the two locking teeth 2, 3 is always impossible if one of the two locking teeth 2, 3 rests with a part of its mirror surface of diameter s on a catch 11.

With regard to Figures 2 and 3, it should also be mentioned that in a preferred further development of the locking device shown there, the springs 27 (see Fig. 1) used to pre-tension the locking teeth 2 to 5 are designed in terms of their pre-tensioning force in such a way that the locking tooth 2, which has completely penetrated into a locking opening 12, is pressed into the locking opening 12 due to the pre-tensioning force of the spring 27 assigned to it until the shoulder 25a provided on the base body 25 of the locking tooth is located slightly below the locking rail 10 in the locking direction R and the base body 25 is supported on the catch 11 with its slightly beveled side surface 25b (having a similar angle to the beveled flanks 23, 24). In the event of a crash, the shoulder 25a hooks onto a catch 11 of the locking rail 10, thereby increasing the crash resistance of the adjustment device. In this variant, the spring forces are to be selected such that the associated spring 27 can press a locking tooth 2 into a locking opening 12 against the frictional forces until the shoulder 25a is located below the locking rail 10.

The invention was described above using a locking device for a longitudinal rail guide for motor vehicle seats. However, it is basically applicable to all adjustment devices in which two mutually

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movable components are to be locked in a defined position. Furthermore, in the above-described embodiments, the locking teeth and in particular their slanted flanks are designed in such a way that no stepless locking of the locking device in any position of the locking teeth in relation to the locking rail is possible. For this purpose, it would be necessary to design the slanted flanks of the locking teeth in such a way that the sum of the projections of the flanks pointing in one direction onto the adjustment direction is equal to the period of the catches and locking openings. Even in such a case, the present invention remains applicable, of course.

Claims (1)

BRO715 Page 17 Expectations 1. Locking device for an adjustable vehicle seat with at least one locking rail running parallel to an adjustment direction, which has periodically arranged catches and locking openings, and with a locking unit which has several locking teeth which can be moved independently of one another along a locking direction into the locking openings and are pre-tensioned in this direction and are arranged differently from the period of the locking openings, whereby a) the locking teeth each have at least one lateral flank running at an acute angle to the locking direction, which is intended to engage with one of the catches, b) the angle is selected such that the locking tooth is not pushed out of its locking position when subjected to a load in the adjustment direction, and c) the locking teeth are arranged in such a way that, in the locking state of the locking device, two locking teeth rest against a notch in opposite directions with respect to the setting direction and at least one of the two locking teeth rests against a notch with its oblique flank, characterized, that the locking teeth (2, 3, 4, 5) have an insertion bevel (21, 22) at their ends facing the locking rail (1), on which the respective locking tooth (2 - 5) in » · mt • « BRO715 a locking opening (12), and that the locking teeth (2 - 5) are mounted in such a way that the respective locking tooth (2 - 5) can move transversely to the locking direction (R) when it slides on the insertion bevel (21, 22) into the locking opening (12). 2. Locking device according to claim 1, characterized in that the locking teeth (2 - 5) are guided with play such that a movement of the locking teeth (2 - 5) in the guide (8) transversely to the locking direction (R) is possible. 3. Locking device according to claim 1 or 2, characterized in that the locking teeth are movably mounted in such a way that the movement of the locking teeth (2 - 5) transversely to the locking direction (R) is possible without a corresponding movement of the associated adjusting part. 4. Locking device according to one of the preceding claims, characterized in that the locking teeth (2 - 5) are tiltable in the plane spanned by the locking direction and the adjustment direction with respect to the locking direction (R). 5. Locking device according to one of the preceding claims, characterized in that each locking tooth (2 - 5) has two oblique flanks (23, 24) which are intended to rest on a catch (11) and which are each adjoined by an insertion bevel (21, 22) towards the locking rail (1). BRO715 Page 19 Locking device according to one of the preceding claims, characterized in that each oblique flank (23) of a locking tooth (2 - 5) is assigned an oblique flank (24) of another locking tooth (2 - 5), the shortest distance (k) between them along the setting direction (E) is on the one hand less than or equal to an integer multiple of the period dimension (P) minus the width (a) of a locking opening (12) and on the other hand greater than or equal to the said multiple of the period dimension (P) minus the width (a) of a locking opening (12) and minus the extension (e+f) of the sum of the projections of an oblique flank (23, 24) and an insertion bevel (21, 22) on the setting direction (E), and that the two locking teeth are supported with their oblique flanks (23, 24) in opposite directions with respect to the setting direction (E) on a catch (11). can. 7. Locking device according to claim 6, characterized in that the shortest distance (k) between opposite oblique flanks (23, 24) of adjacent locking teeth (2, 3; 3, 4; 4, 5) is on the one hand smaller than or equal to the width (b) of a notch (11) and on the other hand larger than or equal to the width (b) of a notch (11) minus the extent (e+f) of the sum of the projections of an oblique flank (23, 24) and an insertion bevel (21, 22) on the adjustment direction (E). BRO715 Page 20 8. Locking device according to one of the preceding claims, characterized in that the locking teeth (2 - 5) are arranged periodically in a period dimension (m) which is smaller than the period dimension (P) of the catches (11) and catch openings (12). (CORRECTION!! ) 9. Locking device according to one of the preceding claims, characterized in that the acute angle (x/2) of the oblique flanks (23, 24) with respect to the locking direction (R) is less than 10°, preferably between 3° and 5°. 10. Locking device according to one of the preceding claims, characterized in that the angle (y/2) of the insertion bevels (21, 22) with respect to the locking direction (R) is between 30° and 60°, preferably approximately 45°. 11. Locking device according to one of the preceding claims, characterized in that the extent (f) of the projection of an insertion bevel (21, 22) onto the adjustment direction (E) is determined by the tolerances of the components (2 - 5, 11, 12) of the locking device in the adjustment direction (E). 12. Locking device according to one of the preceding claims, characterized in that the locking teeth (2 - 5) are rotationally symmetrical.