Adjustment device for longitudinal adjustment of an adjustable vehicle seat

Abstract

The adjustment device (9) for longitudinally adjusting a vehicle seat (2) comprises a first rail (16), in particular an upper rail, and a second rail (18), in particular a lower rail, as well as at least one locking element which locks the two rails (16, 18) in the event of a crash. The locking element (10) is movably mounted on the first rail (16) such that, in the event of a crash, the locking element (10) is moved relatively from a rest position to a locked position by inertial force, and in the locked position, the locking element (10) engages positively with the second rail (18). This mechanically relieves the adjustment drive 6 in the event of a crash and allows for a cost-effective design, particularly in large seating systems.

Description

[0001] The invention relates to an adjusting device for the longitudinal adjustment of a vehicle seat, in particular an electrically adjustable one, with a rail system which has two rails mounted one inside the other so as to be longitudinally displaceable.

[0002] For electrical longitudinal adjustment, a spindle drive is typically used. This drive comprises a spindle running within the rail system, which interacts with a spindle nut to effect longitudinal adjustment. The spindle drive also typically includes a gear system, via which the rotary motion of a frequently flexible drive shaft is transmitted. Such adjustment devices must be designed to be crash-proof, meaning they must be able to absorb the forces generated in the event of an accident. Particularly in a frontal crash, high loads in the direction of travel can be transmitted to the adjustment device, and in particular to the adjustment drive.

[0003] This problem becomes more severe with the increasing mass of the seat to be adjusted. This problem is particularly acute with new seating concepts featuring larger seating systems that offer new comfort features. Due to their weight distribution, specific installation space requirements, and functionalities such as belt integration, etc., such seating systems regularly subject the adjustment drive to high forces, particularly in a frontal crash. Crash safety poses a problem for conventionally deployed systems. To ensure crash safety, the entire adjustment mechanism, including the adjustment drive, would have to be significantly more robustly designed, which would disadvantageously lead to higher costs and increased weight.

[0004] Based on this, the object of the invention is to improve the crash safety of an adjustment device for the longitudinal adjustment of a vehicle seat so that the forces are reliably absorbed in the event of a crash, whereby conventional adjustment drives can continue to be used, in particular without the entire adjustment device and / or the adjustment drive having to be redesigned and made more solid.

[0005] The object is achieved according to the invention by an adjustment device for the longitudinal adjustment of a vehicle seat, in particular an electrically adjustable one, with a rail system comprising two rails mounted longitudinally displaceably within one another, namely a first rail, in particular a so-called upper rail, and a second rail, in particular a so-called lower rail. Furthermore, at least one locking element is arranged, which locks the two rails in the event of a crash, thus blocking any relative movement between these two rails.

[0006] The locking element is movably mounted on the first rail in such a way that in the event of a crash, i.e. when a predetermined acceleration is exceeded in a predetermined crash direction, in particular in the direction of travel, the locking element is moved from a rest position into a locked position due to the inertial force and the locking element engages positively in the second rail in the locked position.

[0007] Therefore, an additional locking element is integrated directly into the rail system. This remains in its rest position during normal operation and does not affect the normal adjustment of the adjustment mechanism. The locking element, however, is only activated when a predetermined acceleration force, which can occur in the event of a crash, is exceeded. In this case, the locking element moves and is essentially activated, moving it into a locked position where it engages positively between the two rails, thus mechanically locking them against each other.

[0008] The locking element therefore forms a crash lock that is triggered and activated when a predetermined acceleration force for which the crash lock is designed is exceeded.

[0009] In the event of a crash, the locking element transfers crash forces directly from one rail to the other rail via the locking element, simultaneously relieving mechanical stress on the remaining adjustment mechanism and, in particular, an adjustment drive, specifically a spindle drive. This allows the adjustment drive to be designed in a simpler and less robust manner than in a situation where the adjustment drive would have to absorb the entire crash forces. The locking element therefore makes it possible to use conventional adjustment mechanisms even in larger seating systems, keeping costs low and also resulting in a lower weight.

[0010] In a preferred embodiment, the second rail has at least one locking recess and preferably several locking recesses arranged one behind the other in the longitudinal direction. In the locked position, the locking element engages in at least one of these locking recesses, typically designed as a window, thus establishing a positive connection with the second rail. For this purpose, the locking element has, in particular, a locking lug, i.e., a recess with which it engages in the locking recess.

[0011] In a useful further development, a retaining element is provided that holds the locking element in its rest position. In particular, this is a mechanical retaining element that engages the locking element in a form-fitting manner.

[0012] In a preferred embodiment, the locking element has a bulge into which the retaining element engages. The retaining element, in turn, has or is formed by an extension or retaining lug protruding toward the locking element. The retaining element ensures that the locking element remains in the rest position during normal operation.

[0013] In a suitable embodiment, the locking element is held in its rest position by spring force. In particular, the spring force presses the locking element with its protrusion against the retaining element. The spring force is preferably dimensioned such that it is overcome when the specified acceleration force is exceeded, thus also taking into account the mass of the locking element, so that the locking element is moved from the rest position to the locked position. The inertial force that occurs when the specified acceleration force is exceeded is therefore greater than the spring force.

[0014] In a useful embodiment, an abutment is formed for the locking element, against which the locking element is pressed due to inertia in the event of a crash and in the direction of the crash. The locking element is therefore displaced towards the abutment in the event of a crash. The abutment exerts a (counter) force on the locking element, whereby the abutment and a corresponding abutment section on the locking element are designed and / or positioned such that the force generated thereby transfers the locking element into its locked position. In this preferred embodiment, the inertia-related force is therefore suitably redirected by means of the abutment in order to bring about a change in the direction of the movement of the locking element, so that it is transferred into the locked position.

[0015] In a preferred alternative embodiment, for example, a guide is designed in the manner of a link for the locking element, so that the locking element is guided along a predetermined path by the inertial force in the event of a crash and, in particular, is transferred into the locking position along an arcuate path. In particular, such that the locking element is displaced toward the second rail, specifically to engage the previously described locking recess.

[0016] According to another alternative embodiment, the locking element, or at least a portion thereof, is preloaded toward the locking position by spring force. Additionally, a locking mechanism for a spring or for the preloaded portion of the locking element is active in the rest position, with this locking mechanism being released due to inertia in the event of a crash.

[0017] In the preferred embodiment with the abutment, which is designed opposite the locking element in the crash direction and thus in particular in the direction of travel, the abutment and the locking element are positioned and / or designed in combination in such a way that a torque is exerted on the locking element so that in the event of a crash it exerts a rotational movement to transfer it into the locking position.

[0018] In a preferred embodiment, the abutment and the corresponding abutment section are arranged off-center with respect to a center of mass of the locking element, so that the desired torque is generated by the off-center, one-sided support and the inertial force.

[0019] Specifically, a tilting movement of the entire locking element around a tilting axis is provided. In particular, the tilting movement pivots a rear end of the locking element downward toward the bottom rail.

[0020] In order to achieve the greatest possible rigidity, the first rail (upper rail) is usually designed in the manner of a profile rail, which can also have several interconnected rail profiles, whereby a profile that is closed or at least largely closed around the circumference is often designed for stability reasons. In a practical design, the first rail has an opening oriented towards the lower rail, which is designed in particular as a recess in a base of the upper rail. The locking element is arranged in the region of the opening and through which the locking element, at least the locking lug, which engages in a form-fitting manner in the second rail, passes during the transition from the rest position to the locked position.

[0021] In the event of a crash, the adjustment device as a whole is typically subjected to such high forces that deformation, particularly of the first rail, occurs. This is exploited in the present case by clamping the locking element, and in particular the previously described locking lug, preferably irreversibly between the two rails and thus also clamping it in the event of a crash.

[0022] For this purpose, the locking lug is clamped between an opening edge of the first rail and an opening edge of the second rail. The locking lug thus rests with a front locking flank against one opening edge and with a rear locking flank against the other opening edge. The opening edges are, in particular, an opening edge of the locking recess in the second rail and an opening edge of the opening in the first rail.

[0023] By additionally utilizing the deformation that occurs during a crash to clamp the locking lug, it is reliably ensured that the locking element remains in the locked position. Since this deformation is plastic, the locking lug is irreversibly and permanently jammed between the two rails.

[0024] According to a preferred embodiment, an adjustment element, and in particular a spindle for longitudinal adjustment, is arranged within the rail system. Specifically, the adjustment element runs longitudinally within a cavity of the rail system. In a preferred embodiment, the locking element is arranged laterally next to this adjustment element. This utilizes the existing installation space, and no additional installation space is required.

[0025] In a preferred embodiment, the locking element is arranged in a guide housing and forms a prefabricated structural unit with it, which is inserted into the rail system, particularly into the top rail. This structural unit therefore forms the crash barrier.

[0026] This offers the advantage that only minor modifications need to be made to a conventional rail system in order to implement the crash protection described here. The assembly and thus the guide housing are placed at a suitable location in the rail system, specifically on the top rail, and fastened there in a suitable manner, for example by welding, gluing, locking, or screwing. Since the crash barrier has no function during normal operation, it is not subjected to any stress. And even in the event of a crash, the fastening of the crash barrier in the rail system is irrelevant, as its effect is based on the locking element being moved into the locked position and, in particular, the locking lug being irreversibly clamped there, as described above. The guide housing does not have to be able to absorb or transmit any forces.

[0027] All of the features described above, such as the abutment, the holding element or a spring element generating the spring force, are preferably integral functional components of the structural unit and / or the guide housing.

[0028] In a preferred embodiment, a chamber is formed in the guide housing, in which a spring element is located, via which a spring force is generally exerted on the locking element, in particular to hold it in its rest position, as previously explained. The spring element is arranged, in particular, opposite the previously described retaining element.

[0029] The guide housing preferably has a side wall that runs longitudinally and, in particular, parallel to a lateral rail wall. Further walls are formed transversely thereto, which are specifically designed to guide the locking element. The guide housing is preferably open on one side in the transverse direction, so that the locking element can be inserted into the guide housing.

[0030] In a preferred embodiment, the locking element has an upper and a lower edge, over which the locking element is mounted for longitudinal displacement, so that in the event of a crash, it is guided along these edges. These interact with corresponding guide surfaces, which are formed in particular on the guide housing. For this purpose, the guide housing has, in particular, an upper and a lower guide web, along which the edges of the locking element slide.

[0031] In a preferred embodiment, several locking elements are also provided, which are arranged one behind the other, particularly in the longitudinal direction of the rail system. This measure increases the locking force and thus crash safety. This is particularly the case for seating systems that use very long rails and where, for example, several adjustable seats are mounted on the rail system.

[0032] In a preferred embodiment, the locking element is designed as a flat sheet metal component, particularly made of steel, which extends longitudinally and forms the locking lug on its lower edge. Overall, it is therefore a simple, flat component that can be manufactured cost-effectively, for example, by stamping from a flat sheet of metal.

[0033] An embodiment of the invention is explained in more detail below with reference to the figures. These show: Fig. 1 a perspective side view of a seat system for a motor vehicle, Fig. 2 a partial longitudinal section through a rail system with a locking element as a crash barrier, Fig. 3 an exploded view of a structural unit forming the crash barrier with a guide housing and a locking element, Fig. 4 a perspective partial and partially sectioned view of the rail system in the area of ​​the locking element, as well as Fig. 5 a cross-sectional view through the rail system in the area of ​​the locking element.

[0034] In Fig. 1 shows a seating system with two vehicle seats 2, which are mounted together on a rail system 4 and are electrically adjustable in or against a longitudinal direction L. In the present case, the longitudinal direction L, in the assembled state and during operation, corresponds to a (forward) direction of travel of the vehicle. An electric adjustment drive 6, which is designed in particular as a spindle drive, is arranged for the electrical adjustment. In the area marked with a dashed circle, a crash lock 8 is attached, as will be explained in detail below in connection with the other figures. The rail system 4 together with the adjustment drive 6 and the crash lock 8 form an adjustment device 9.

[0035] In the exemplary embodiment, the crash barrier 8 is designed as a pre-assembled unit (see in particular also Fig. 3), which has as essential components a locking element 10 and a guide housing 12 in which the locking element 10 is located and in which it is guided. Furthermore, the crash lock 8 in the exemplary embodiment also has a spring element 14. The crash lock 8 preferably does not have any further elements.

[0036] The rail system 4 comprises two parallel rail tracks, each of which has a first rail, hereinafter referred to as the upper rail 16, and a second rail, hereinafter referred to as the lower rail 18. The two rails 16, 18 are mounted on one another for longitudinal movement. In the assembled state, the lower rail 18 is firmly connected to a load-bearing body component of the vehicle, particularly by screws.

[0037] The crash barrier 8 is arranged in a free internal cavity, particularly in the upper rail 16. For this purpose, the guide housing 12 is suitably attached to the upper rail 16, specifically to a side wall of the upper rail 16.

[0038] The upper rail 16 can consist of several interconnected rail profiles. It has an opening 20 on its underside, oriented toward the lower rail 18. This opening is formed, for example, as a recess in an otherwise closed base of the upper rail 16. Alternatively, the upper rail 16 is open downwards toward the lower rail 18.

[0039] The lower rail 18 has a plurality of locking recesses 24 on the bottom side, which follow one another in the longitudinal direction L, in particular at the same distance from one another.

[0040] The opening 20 in the upper rail 16 is formed below the crash barrier 8 and in particular below the locking element 10. At the same time, the guide housing 12 also has a passage area 22 in the direction of the opening 20 of the upper rail 16 and thus in the direction of the lower rail 18 or is open in the direction of the lower rail 18.

[0041] The exact structure and function of the crash lock 8 is explained in connection with the Fig. 2 and Fig. 3 explains in more detail: During normal operation, the locking element 10 is in a rest position as shown in Fig. 2 is represented by a solid line of the locking element 10. In the event of a crash, especially in a frontal crash and the associated high forces in the longitudinal direction L (direction of travel), the locking element 10 is displaced in the crash direction due to inertia and transferred into a locked position. In a frontal crash, the crash direction corresponds to the direction of travel and thus the longitudinal direction L. This movement process is in Fig. 2 is illustrated by a dashed representation of the locking element 10 in two different positions.

[0042] The locking element 10 is preferably a flat sheet metal component, particularly made of steel, with high rigidity. It extends in the longitudinal direction L from a rear end to a front end. It has an upper edge 25 and a lower edge 26, each extending in the longitudinal direction L. A locking lug 28 is formed on the lower edge 26, which is oriented downward toward the lower rail 18. In the longitudinal direction L, the locking element 10 has an indentation 30 directly adjacent to the locking lug 28.

[0043] The longitudinally leading edge of the locking lug 28 forms a front locking flank 32. A rear locking flank 34 is formed opposite, specifically by a portion of a front edge of the rear end. At this front edge, the locking element 10 further comprises a depression or indentation forming a retaining element 36. Associated with this depression, a retaining lug 38 is formed on the guide housing 12 at its rear end. When the locking element 10 is in the rest position, this retaining lug engages the retaining element 36 formed by the indentation, thereby securing the locking element 10, specifically at a defined height.

[0044] In the exemplary embodiment, a downwardly protruding nub 40 is formed on the lower edge side 26 in a front portion. The locking element 10 is therefore curved at this point.

[0045] At the front end, the locking element 10 has a guide nose projecting forward, which serves to hold the spring element 14.

[0046] The guide housing 12 also extends, corresponding to the locking element 10, from a rear end to a front end in the longitudinal direction L. The spring element 14 is arranged at the front end. For this purpose, the guide housing 12 forms a chamber 42 in which the spring element 14 is located and transmits a spring force to the locking element 10 counter to the longitudinal direction L. The spring force therefore presses the locking element 10 with its rear end against a rear wall of the guide housing 12 and specifically against the retaining lug 38, so that the locking element 10 is fixed in its rest position.

[0047] As is particularly evident from Fig. As can be seen in Figure 3, the guide housing 12 has a flat, lateral base plate forming a side wall 44. The previously described chamber 42 and the previously described retaining lugs 38 are formed over further wall areas. On the upper side, the guide housing has an upper guide web 46. In the rest position, the locking element 10 rests with its upper edge 25 against this upper guide web 46 and is guided by it.

[0048] On the opposite underside, the guide housing 12 has a lower guide web 48, which adjoins the passage area 22 at the front. The locking element 10 rests on this lower guide web 48 with its lower edge side 26 and, in particular, with the knob 40.

[0049] As specifically from the Fig. 3, the guide housing 12 in the exemplary embodiment has, on its side opposite the side wall 44, an open region which preferably extends almost (e.g., greater than 90%) over the entire length of the locking element 10 and preferably also almost or over the entire width of the locking element 10, so that the latter can be inserted laterally into the guide housing 12 from one side. The guide housing 12 is therefore designed as an open housing on one side.

[0050] At its front end, the guide housing 12 further comprises an abutment 50 against which the locking element 10 is supported in the event of a crash with an abutment section 52. In the exemplary embodiment, this abutment section 52 is designed in the manner of a knob projecting forward. It should be emphasized that the abutment section 52 is arranged off-center. This means that the abutment section 52 - with respect to the longitudinal direction L - is arranged laterally next to and in particular above a center of gravity M of the locking element 10 and in particular above a center of gravity line running parallel to the longitudinal direction. The center of gravity line runs through the center of gravity M.

[0051] The locking element 10 is freely mounted within the guide housing 12 and is preferably held in its rest position exclusively by the spring force of the spring element 14 in cooperation with the holding element 36 and the holding lug 38.

[0052] As is especially evident from the Fig. 2, the opening 20 has an opening edge 20A, which is formed by an end face of a section of the upper rail 16. This section and thus the opening edge 20A are preferably positioned such that, in the rest position, the locking element 10 is arranged with a rear support section 54 formed downstream of the locking lug 28 above this section of the upper rail 16, and in particular is additionally supported on the upper rail 16 in the rest position.

[0053] In the event of a crash, an inertial force acting in the longitudinal direction L is applied to the locking element 10, causing it to be displaced forward in the longitudinal direction L. This initially releases the holder in the region of the holding element 36. Preferably, the locking element 10 is displaced so far in the longitudinal direction that the rear end and thus the support section 54 are located longitudinally in front of the opening edge 20 and thus above the opening 20. The position after the longitudinal displacement is indicated by one of the two dashed lines.

[0054] During this longitudinal displacement, the locking element 10 is pressed with its abutment section 52 against the abutment 50 on the guide housing 10. Due to the off-center placement - i.e., due to the arrangement of the abutment 50 and the abutment section 52 laterally next to and in particular above the center of mass M - a torque is generated, so that the locking element 10 is rotated in the direction of the lower rail 18 due to the inertial force. Preferably, the locking element 10 is supported in particular with its knob 40 on the lower guide web 48, so that in the area of ​​this knob 40, a pivot bearing is formed, so to speak.

[0055] The locking lug 28 thereby engages in the locking recess 24 and the front locking flank 32 comes to bear against an opening edge 24A of the locking recess 24. This already achieves a positive locking and thus a blocking between the two rails 16, 18.

[0056] In addition, the present invention further exploits the fact that the upper rail 16 is deformed by the resulting crash forces, so that it is virtually compressed in the longitudinal direction L, whereby the opening edge 20A of the opening 20 is also displaced in the longitudinal direction L and pressed against the rear locking flank 34 of the locking lug 28. As a result, the locking lug 28, in particular the two locking flanks 32, 34, are clamped between the two opening edges 20A, 24A. This results in a permanent, solid blocking of the relative displacement between the two rails 16, 18.

[0057] Based on the Fig. 4 and Fig. 5 clearly shows the positioning of the crash barrier 8 within the rail system 4. The entire assembly forming the crash barrier 8 is arranged within a cavity of the rail system 4, specifically within the upper rail 16. An adjustment element, in particular a spindle 56 of the adjustment drive 6, designed as a spindle drive, preferably also runs within this cavity.

[0058] How special from Fig. As can be seen in Figure 4, the crash lock 8 is arranged laterally next to the spindle 56. Therefore, no additional installation space is required.

[0059] The two rails 16, 18 are interlocked and slidably guided relative to each other as usual. In the illustrated example, the upper rail 16 consists of several firmly connected rail elements. The upper rail 16 is encompassed by the lower rail 18 at its edges.

[0060] The crash lock 8 described here mechanically relieves the load on the adjustment drive 6 in the event of a crash. The forces to be absorbed are therefore partially absorbed by the crash lock 8 and partially by the adjustment drive 6. Preferably, several such crash locks 8 are arranged offset one behind the other in the longitudinal direction L. List of reference symbols 2 vehicle seats 4 rail systems 6 Adjustment drive 8 Crash lock 9 Adjustment device 10 locking element 12 guide housings 14 Spring element 16 Top rail 18 Bottom rail 20 Opening 20A Opening edge of the opening 22 Passage area 24 locking recess 24A Opening edge of the recess 25 upper edge 26 lower margin 28 locking lug 30 indentation 32 front locking flank 34 rear locking flank 36 Holding element 38 retaining lug 40 studs 42 Chamber 44 side wall 46 upper guide bar 48 lower guide bar 50 abutments 52 abutment section 54 support section 56 spindle L longitudinal direction M center of mass

Claims

[1] Adjusting device (9) for the longitudinal adjustment of an adjustable vehicle seat (2) with a rail system (4) extending in a longitudinal direction (L) with two rails mounted one inside the other so as to be longitudinally displaceable, namely a first rail (16), in particular an upper rail, and a second rail (18), in particular a lower rail, with at least one locking element which locks the two rails (16, 18) in the event of a crash, wherein the locking element (10) is movably mounted on the first rail (16) in such a way that in the event of a crash the locking element (10) is relatively displaced from a rest position into a locked position due to the inertial force and the locking element (10) engages positively in the second rail (18) in the locked position. [2] Adjusting device (9) according to the preceding claim, wherein the second rail (18) has at least one locking recess (24) and in particular a plurality of locking recesses (24) in the longitudinal direction (L), and the locking element (10) has a locking lug which engages in the at least one locking recess (24) in the locking position. [3] Adjusting device (9) according to one of the preceding claims, wherein a holding element (36) is formed and the locking element (10) is held in its rest position by the holding element (36). [4] Adjusting device (9) according to one of the preceding claims, wherein the locking element (10) is held in its rest position by spring force. [5] Adjusting device (9) according to one of the preceding claims, wherein an abutment (50) is formed for the locking element (10) and in the event of a crash, the locking element (10) is pressed against the abutment (50) in a crash direction, in particular in the longitudinal direction (L) due to inertia and a force is exerted on the locking element (10) by the abutment (50), so that the locking element (10) is transferred into its locking position. [6] Adjusting device (9) according to the preceding claim, wherein the abutment and the locking element (10) are designed such that a torque is exerted on the locking element (10) and this exerts a rotational movement and in particular a tilting movement in the event of a crash, wherein the locking element (10) is supported off-center on the abutment (50) so that the torque is generated. [7] Adjusting device (9) according to one of the preceding claims, wherein the first rail (16) has an opening (20) oriented in the direction of the second rail (18) through which the locking element (10) passes during the transition from the rest position to the locking position. [8] Adjusting device (9) according to one of the preceding claims, wherein the first rail (18) (16) is subject to deformation in the event of a crash, such that the locking element (10) is clamped, in particular irreversibly, between the two rails (16, 18). [9] Adjusting device (9) according to the preceding claim, wherein a locking lug (28) of the locking element (10) is clamped between an opening edge (20A) of the first rail (16) and an opening edge (24A) of the second rail (18). [10] Adjusting device (9) according to one of the preceding claims, wherein an adjusting element, in particular a spindle (56) for the longitudinal adjustment is arranged within the rail system (4) and the locking element (10) is arranged laterally next to the adjusting element (56). [11] Adjusting device (9) according to one of the preceding claims, wherein the locking element (10) is arranged in a guide housing (12) with which it forms a structural unit which is inserted into the rail system (4). [12] Adjusting device (9) according to the preceding claim, wherein the guide housing (12) has a chamber (42) in which a spring element (14) is located, via which a spring force is exerted on the locking element (10). [13] Adjusting device (9) according to one of the preceding claims, wherein the locking element (10) has an upper and a lower edge side (25, 26) over which it is mounted so as to be longitudinally displaceable. [14] Adjusting device (9) according to one of the preceding claims, wherein the locking element (10) is designed as a flat sheet metal component which extends in the longitudinal direction (L) and which has a locking lug (28) on a lower edge side (26) with which the locking element (10) engages in a form-fitting manner in the second rail (18) in the locking position. [15] Adjusting device (9) according to one of the preceding claims, in which several locking elements (10) are arranged in the rail system (4).

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