Actuator device for the seat adjustment in a motor vehicle

An actuator device for the seat adjustment in a motor vehicle, exhibiting at least one ratchet fitting (1), a transmission element (2) and an actuator element (3), whereby the transmission element (2) is centered in the ratchet fitting (1) with a centering element (4) such that the centering element (4) allows for a limited torsional backlash between the transmission element (2) and the ratchet fitting (1) and creates a restoring force against the rotation, whereby said transmission element (2) is connected in a torsionally stiff manner to the actuator element (3), whereby the actuator element (3) is connected in a form-fitting manner to the centering element (4).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from German Patent Application 10 2010 019 029.2-14 titled “Actuator Device for the Seat Adjustment in a Motor Vehicle”, which was filed on May 3, 2010 and incorporated fully herein by reference.

TECHNICAL FIELD

The invention relates to an actuator device for the seat adjustment in a motor vehicle as well as to a centering element.

BACKGROUND INFORMATION

With motor vehicle seat adjustments, it is currently common to use ratchet fittings that can be unlocked by the user via an actuator element, for example a lever, and in the unlocked condition allow for pivoting an element of the vehicle seat, in particular the backrest of the vehicle seat. Often, these ratchet fittings are provided on both sides of the vehicle seat. In such cases, the unlocking mechanism must be designed in such a way as to allow for the simultaneous unlocking of both ratchet fittings.

The required mechanical coupling of the two ratchet fittings with the actuator element necessary for this brings with it the problem of the relative position tolerances of the two ratchet fittings towards each other. Attaching an actuator element on one single fitting can for example be accomplished with simple clip connectors as is disclosed in DE-GM 75 21 224. However, if for example two fittings are to be coupled, as is shown in EP 0 098 400 B1, then both fittings must be coupled using a transmission element, which, for one, requires increased demands on the position tolerances of the fittings in relation to each other, and secondly entails a more complex assembly of the actuator device. For this reason, FR 2926644 A1 provides an interim element between the axis and the actuator element that is used to support the actuator element on the transmission element in a tortionally rigid but axially movable fashion and attach it to the fitting in a rotating but in the axial direction of the transmission element fixed manner.

SUMMARY

It is the underlying objective of the invention to present an actuator device for a seat adjustment in a motor vehicle that allows, first, high production tolerances and, second, enables a simple and thus cost-effective assembly.

This objective is achieved through an actuator device for a seat adjustment in a motor vehicle as well as through a centering element. The invention features an actuator device for the seat adjustment in a motor vehicle, exhibiting at least one ratchet fitting, a transmission element and an actuator element, whereby the transmission element is centered in the ratchet fitting with a centering element such that the centering element allows for a limited torsional backlash between the transmission element and the ratchet fitting and creates a restoring force against the rotation, whereby said transmission element is connected in a torsionally stiff manner to the actuator element, whereby the actuator element is connected in a form-fitting manner to the centering element.

According to the invention, at least one ratchet fitting is provided that is actuated by a transmission element. The transmission element is a shaft or rod or a similar torsionally stiff component that is connected in a torsionally stiff manner to the actuator element, which may be a release lever, for example. Essential for the invention is that the connection of the transmission element to the ratchet fitting is made through an inventive centering element. The centering element centers the transmission element in the ratchet fitting and due to its design allows for a limited torsional backlash between the transmission element and the ratchet fitting. However, by its design it generates a restoring force against the rotation as long as the rotation is within the range of the allowed torsional backlash. The actuator element that is torsionally stiff connected to the transmission element is at the same time connected to the centering element in a form-fitting manner.

The actuator element is held in a defined position in relation to the ratchet fitting by the form-fitting connection with the centering element. However, the actuating impulse, which is a rotational movement around the axis of the transmission element, is not transferred directly from the actuator element to the centering element, rather initially from the actuator element to the transmission element. The transmission of the actuating impulse from the transmission element to the ratchet fitting then occurs via the centering element, which allows the described torsional backlash with an elastic restoring force between the ratchet fitting and the transmission element. The torsional backlash serves the purpose of compensating for manufacturing and installation tolerances. These tolerances play a role in particular when ratchet fittings are attached to both sides of the seat and shall be actuated using the same actuator element, i.e., by using the same transmission element, which advantageously connects the two ratchet fittings.

Advantageously, the connection between the actuator element and the transmission element is designed such that while torsionally stiff it remains axially moveable to compensate for axial position tolerances between the actuator element and the transmission element, whereby advantageously the axial distance of the actuator element is determined merely by the form-fitting connection with the centering element. Advantageously, this form-fitting connection of actuator element and centering element is not designed in a torsionally stiff manner, which can be achieved, for example, in that the actuator element is connected to the centering element by form-fitting elements, which encompass a form-fitting counter element at the centering element. The form-fitting counter element can be a ring-shaped collar on the centering element. Advantageously, the form-fitting elements are arranged at equal distances to the axis of the transmission element such they are able to encompass the ring-shaped collar and to move thereon in the circumferential direction. Advantageously, the form-fitting elements are arranged distributed along the circumference of a circle around the axis of the transmission element and are designed such that the form-fitting connection can be established simply by attaching the actuator element onto the centering element.

With such a connection the installation of the seat is made much easier, as the transmission element that is connected, for example, with a second ratchet fitting or a further transmission element leading to the same, which, for example, can be done by a welding process, can be guided loosely through the first ratchet fitting, and can be centered and easily secured in the latter simply by sliding on the centering element, after which an assembly of the actuator element is also possible in a simple manner by a further push-on procedure. Advantageously, here the centering element is designed such that it exhibits an essentially hollow cylinder-like base section. In the area of its internal surface, the base section shaped like a hollow cylinder exhibits a contour that is suited for the form-fitting engagement at a counter-contour to be provided at the transmission element. The contours are designed such that they allow for one, due to their dimensions in relation to the counter contour, a limited torsional backlash, and second present a form-fit that is axially moveable to allow the transmission element to be pushed on and to compensate for the axial tolerances. Preferably, contouring involves at least one groove extending essentially in an axial direction and allowing the torsional backlash based on its width selected in the circumferential direction.

To secure its axial position relative to the ratchet fitting, the centering element preferably exhibits stop surfaces, which when pushing the centering element onto the transmission element strike in the end position of the centering element at the ratchet fitting in the axial direction.

The section of the centering element that points away from the seat in this end position is designed such that it features a form-fitting counter element, which can be a neck collar, for example. This form-fitting counter element is preferably located in the area of the end of the centering element that points in the axial direction away from the seat.

Also provided at the centering element are spring elements, which are suited to launch a spring force in the circumferential direction into a counter contour to be provided at the transmission element. Advantageously, the spring elements can be finger-like protrusions that following the main body in the axial direction and in the assembled state rest against the counter contour of the transmission element in the direction of the circumference.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The invention features an actuator device10,FIG. 1, for the seat adjustment in a motor vehicle. The actuator device includes at least one ratchet. fitting1, a transmission element2and an actuator element3, whereby the transmission element2is centered in the ratchet fitting1with a centering element4such that the centering element4allows for a limited torsional backlash between the transmission element2and the ratchet fitting1and creates a restoring force against the rotation. Typically, the ratchet fitting1is designed such that it exhibits a central borehole for receiving an actuator mechanism that is suited for receiving the transmission element2with the release of the ratchet fitting1occurring through a rotation of the transmission element2. Typically a driver la is provided at the ratchet fitting1, for example designed in the shape of a cam that interacts with a suitable contour of the transmission element2. According to the invention, the transmission element2, which may be a rod, a tube, a shaft or a similar torsionally stiff structure, is in its radial dimensions significantly smaller dimensioned than would be appropriate for conventional direct mounting in the borehole of the ratchet fitting1with regard to a secure support. Instead, a centering element4is pushed onto the transmission element2and inserted into the borehole in the ratchet fitting1until it reaches an end position defined by a stop. The stop may be, for example, designed as a shoulder4din the contour of the cylindrical section of the centering element4, however, alternatively areas4glocated between the spring elements4cmay also serve as an axial stop. In its preferred embodiment, the centering element4exhibits form-fitting elements4fthat secure the same in the end position of the centering element4in the manner of a clip connection in its end position.

In this manner, the exemplary centering element according to the invention fulfills a dual function as a result of its geometry: First, it allows for easy installation of the transmission element2in the ratchet fitting1, as the transmission element2can be inserted initially only loosely through the significantly larger borehole into the ratchet fitting1because of the dimensioning differences made possible by the centering element4, in order to then establish the fit between the transmission element2and the ratchet fitting1by pushing the centering element4that establishes the fit and is significantly easier to handle during the installation due to its small size than the transmission element2itself.

Second, the centering element4has the function to compensate for position tolerances. It fulfills this function first by an axially movable support on the transmission element2, and second by the form-fit with the contour2aof the transmission element2, which is established by spring elements4caccording to the invention. The grooves4eof the exemplary centering element4are designed wider in the direction of the circumference than the elements of the counter contour2aof the transmission element2engaging in the grooves. Thus, the grooves4eallow for a limited torsional backlash between the centering element4and the transmission element2. The spring elements4c, on the other hand, rest in the circumferential direction against the counter contour2aof the transmission element2. This allows them to transfer a spring force onto the counter contour2a, which counteracts a rotation that is enabled to a limited extent by the dimensioning of the grooves4eand the counter contour2a. The release of the ratchet fitting1is done indirectly via the centering element4, which has a suitable contour and actuates the driver element1athat is present at the ratchet fitting1and in the shown example is a cam. In the example shown, this is advantageously solved such that the spring elements4cattack both on the counter contour2aof the transmission element2and on the driver element1aof the ratchet fitting1.

The actuator element3is connected torsionally stiff to the transmission element2, but pushed in the axial direction only loosely onto the transmission element. The relative positioning of the actuator element3in relation to the ratchet fitting1and thus to the vehicle seat is done via the centering element4. For this purpose, the actuator element3is connected to the centering element4in a form-fitting manner. In the shown example, the form-fit is established by protrusions3a, which are distributed along the circumference of a circle around the axis5of the transmission element2at equal distances to this axis5and encompass in a hook-like manner form-fitting counter element4as designed like a neck collar.

Provided at the actuator element3is a stop collar3bthat provides for a defined distance of the actuator element3to the ratchet fitting1and thus to the vehicle seat. This allows first for positioning of the actuator element3in the axial direction defined relative to the ratchet fitting1and the motor vehicle seat, while at the same time being insensitive to axial position tolerances of the transmission element2; through the clip-like form-fitting elements3adistributed on the circumference, it also allows for rotatable, but axially defined positioning of the actuator element3on the motor vehicle seat, which also allows for high tolerances in the radial direction between the transmission element2and the actuator element3, without giving the user the impression of a loose attachment of the actuator element3on the motor vehicle seat. In addition, the actuator element3can be realized in simple fashion by simply attaching it to the transmission element2and the centering element4, with the resulting connection in the example shown having also the advantage of easy separability for repair or maintenance purposes.