GB2150020A

GB2150020A - Mechanism to drive a longitudinally slidable vehicle seat

Info

Publication number: GB2150020A
Application number: GB08428804A
Authority: GB
Inventors: Ulrich Budde
Original assignee: Alfred Teves GmbH
Current assignee: Continental Teves AG and Co oHG
Priority date: 1983-11-26
Filing date: 1984-11-14
Publication date: 1985-06-26
Also published as: GB8428804D0; FR2555526B1; GB2150020B; FR2555526A1; DE3342910A1

Abstract

In a mechanism to drive a longitudinally slidable vehicle seat, the seat frame 1 is furnished with a longitudinal rail 8 arranged in the adjusting direction and having a roughly Z-shaped cross-section, which longitudinal rail 8 slides in an anchor block 10 welded or bolted to the floor 4 of the vehicle, together with the seat frame 1. Between the stays or lateral members 14, 15 on anchor block 10 there is introduced a spindle nut 11, into which an adjusting spindle 12 is screwed, that extends parallel to the said longitudinal rail 8 and whose other end is supported in a motor-and-gear unit 30 fastened at the other end of the seat frame 1, to the longitudinal rail 8 or to a transverse strut 7. The said lateral members 14, 15 are furnished with openings through which the adjusting spindle 12 passes. When the motor is switched on, the spindle is rotated and the spindle nut 11 moves the seat along rails 5, 6 in the direction of arrow A. <IMAGE>

Description

SPECIFICATION Mechanism to drive a longitudinally slidable vehicle seat The invention relates to a mechanism to drive a longitudinally slidable vehicle seat, with two slide rails arranged at the floor of the vehicle and provided with slide shoes to support the one end of the seat frame and with a stationary anchor block to supportthe other end of the seat frame, with a longitudinal rail secured to the seat frame and sliding in the anchor block.

Vehicle seats are already known in which the vehicle seat frame is retained and guided with each of its rear ends in rails fastened to the vehicle floor, the front end of the seat frame sliding in a single anchor block at the floor of the vehicle for which purpose a longitudinal rail extending in the adjusting direction is secured to the frame. In this configuration, the anteriorly arranged anchor block is formed from a plate metal blank and has two pairs of lateral members or stays whose ends are each welded to the floor of the vehicle. In between those two pairs of stays, the anchor block is, furthermore, provided with a roughly L-shaped recess which extends in sliding direction and in which the longitudinal rail slides which latter is rigidly coupled to the seat frame.To this end, the longitudinal rail is furnished at its upper and its lower longitudinal edges with one each guide face bent off laterally, the two guide faces extending in opposite directions, so that there results a roughly Z-shaped cross-section. Customarily, a sliding pad of plastics material is interposed between the longitudinal rail and the anchor block to prevent the rail from rattling in its guide in the anchor block. Adjustment of the seat in longitudinal direction is by means of a locking mechanism secured to the anchor block and co-acting with holes provided in the longitudinal rail.

An object of the present invention is to create a particularly inexpensive, reliable and easily mountable driving mechanism for a vehicle seat of the known type. In addition, the driving mechanism must be conceived so as to be adapted for mounting in lieu of the existing locking mechanism for the manual adjusting device at the anchor block without the need of any substantial modifications at the anchor block or at the seat frame.

According to the present invention, there is provided a mechanism to drive a longitudinally slidable vehicle seat, with two slide rails arranged at the floor of the vehicle and provided with slide shoes to support the one end of the said seat frame and with a stationary anchor block to support the other end of the said seat frame, with a longitudinal rail secured to the said seat frame and sliding in the said anchor block, characterised in that parallel to and at a distance from the said longitudinal rail, there is provided an adjusting spindle having one end supported rotatably but not slidably in the longitudinal direction in a motor-and-gear unit coupled to the said longitudinal rail and/or to a transverse strut of the said seat frame, the said adjusting spindle coacting with a spindle nut which is unslidably retained by the said anchor block.

Advantageously, the anchor block is provided with at least two arms or lateral members extending at right angles to the adjusting direction and retaining the spindle nut or an adjusting nut between them. The two arms or lateral members of the anchor block are expediently furnished each with an opening through which the adjusting spindle passes.

In order to render possible its easy and quick introduction into the anchor block, the spindle nut is configurated as a substantially parallelepiped-shaped body whose diametrally opposite frontal faces at least partly abut with the inside faces of the arms or lateral members, with the threaded bore penetrating through both frontal faces being aligned with the openings in the lateral members.

In a preferred embodiment, the two arms or lateral members of the anchor block positioned opposite each other are arranged in intersecting planes and the frontal faces of the adjusting nut configurated as corresponding inclined surfaces.

To render possible a smooth introduction of the spindle nut into the anchor block rigidly located at the floor of the vehicle even if the lateral members of the anchor block fail to extend vertically relative to the vehicle floor, the frontal faces of the spindle nut being positioned diametrally opposite each other and abutting with the lateral members of the anchor block are configurated at least partly in the shape of cylindrical or conical surfaces.

The adjusting nut is furnished with a projection extending at right angles relative to the longitudinal axis of the threaded bore in order to ensure ease of handling of the adjusting nut.

The introduction of the spindle nut into the anchor block is also eased in that the spindle nut is formed with a collar projecting outside and encircling one of the openings of the threaded bore, said collar having an outside diameter sized such to render it introducible into the opening provided in the one lateral member for the adjusting spindle to pass through it. Beyond this, the forementioned collar bears the advantage of safeguarding that the adjusting spindle does not come in touch with the lateral members of the anchor block upon mounting.

Further features of the present invention are characterised in more detail in the attached patent claims.

An embodiment of the invention will now be described with reference to the accom panying drawings, in which: Figure 1 is a top plan view on the frame of a vehicle seat with an adjusting mechanism driven by an electric motor, in a substantially scaled-down and simplified representation; Figure 2 is a view, partly in cross-section, of the seat of an automotive vehicle as per Figure 1, viewed along the longitudinal axis of its longitudinal rail and in a scaled-up representation as compared to that in Figure 1; Figure 3 is the front view, partly in crosssection, of the anterior anchor block of the vehicle seat; Figure 4 is a side view of the front anchor block of Figure 3; Figure 5 is a top plan view of the front anchor block of the vehicle seat; Figure 6 is a top plan view of the spindle nut of the front anchor block; and Figure 7 is a perspective and slightly scaled-up representation of the spindle nut according to Figure 6, the dashed lines indicating the outlines of a simplified version of a spindle nut.

As shown in Figure 1, the frame 1 of the vehicle seat is furnished on either side with a respective slide shoe 2, 3 each of which is supported slidably in the direction of the arrow A, in a rail 5, respectively 6, which is rigidly secured to the floor 4 of the vehicle.

The frame 1 is provided with a transverse strut 7 which is, in its turn, rigidly coupled with the front portion 1 a of the frame 1 by means of a longitudinal rail 8 having a Zshaped cross-section, and which is slidably retained and guided in an anterior stationary anchor block 10 with a sliding pad 9 being interposed in between. In the anchor block 10, there issupported a spindle nut 11 with which the adjusting spindle 1 2 co-acts, with the one end of the adjusting spindle 1 2 being supported in a gear with motor 30 in such a manner that the adjusting spindle 1 2 is rotated when the motor is switched in and the stationarily retained spindle nut 11 moves the frame 1 in the direction of the arrow A or in contrary direction (depending on the sense of rotation of the adjusting spindle 12).

As shown in Figure 6, the spindle nut 11 is configurated as a separate element having a shape and size so as to fit exactly between the two lateral members 14 and 1 5 of the anchor block 10. For the introduction of the spindle nut 11 into the anchor block 10, first of all a collar 1 6 provided at the frontal face 11 a of the spindle nut 11 is inserted (in the direction of the arrow B in Figures 5 and 6) into opening 1 7 provided in the lateral member 14 and subsequently the other end is introduced with its frontal face 11 b into the anchor block 10 in the direction of the arrow C, where it abuts with the inside surface of the lateral member 1 5 in a way that the opening 1 9 of the lateral member 1 5 comes to be aligned with the threaded bore 1 8. After the adjusting spindle 1 2 is screwed into the threaded bore 1 8 of the spindle nut 11, the latter is firmly retained between the lateral members 1 4, 1 5 of the anchor block 10, as a result whereof upon rotating the adjusting spindle 12, the latter is movable together with the frame 1 of the vehicle seat relative to the floor 4 of the vehicle.

As is revealed by Figures 3, 4 and 5, the anchor block 10 which is bent to shape from a plate metal blank, is furnished with a total of four lateral members 14, 15 and 20, 21 respectively, one pair of lateral members being arranged on either side of the longitudinal rail 8 (also refer to Figure 2). The lower ends 22, 23 and 24, 25 of the lateral members 1 4, 1 5 and 20, 21, respectively which are directed toward the dished floor 4 of the vehicle are each welded to the floor 4 of the vehicle. Through a perpendicular back portion 26 positioned parallel to the longitudinal rail 8, a stay 27 running parallel to the floor 4, and a bridge portion 28, the four lateral members, 14, 15, 20, 21 are connected with one another to form one single element.

The spindle nut 11 retained by the anchor block 10 is configurated as a substantially parallelepiped-shaped body whose frontal faces 11 a, 11 b located opposite each other are partly rounded off or configurated as halves of conical surfaces running obliquely relative to the top side and to the bottom side 11 e. In addition, the spindle nut 11 is furnished with a lateral projection 29 which facilitates the introduction of the spindle nut 11 into the anchor block 10 and prevents the spindle nut 11 from rotating about the longitudinal axis L of the threaded bore 1 8. Additionally, the spindle nut is provided with a rib or cam 31 with which the spindle nut 11 is in abutment against the back portion 26.

The bottom surface 11 e rest on the vehicle floor 4 when the frontal faces 11 a, 11 b are in abutment with the inside surfaces of lateral members 14 and 1 5. In the version illustrated in Figure 6, the collar 1 6 is configured as a separate ring or bushing made of a plastic material which is fastened button-wise in the threaded bore 1 8. The collar 1 6 projects beyond the frontal face 11 a just sufficiently so as to be firmly seated in the opening 1 7 which is provided in the lateral member 14.

Collar 1 6 may alternatively be of metal. In case the adjusting spindle 1 2 fails to run perfectly parallel to the longitudinal rail 8 fastened to the frame 1 of the vehicle seat or in case during its slide in the direction indicated by the arrow A, the frame 1 fails to move in parallel direction relative to the two rails 5 and 6 rigidly fixed to the floor 4, the spindle nut 11 may exercise a slight tumbling movement about its support at the collar 1 6 since the opening 1 9 in the lateral member 1 5 is sized slightly larger than the external diameter of the adjusting spindle 1 2.

At the rear end of the seat frame 1 of the vehicle seat, there is arranged the motorandgear unit 30 which is bolted or riveted to the frame 1 at the end of the longitudinal rail 8 in the range of the transverse strut 7. The one end of the adjusting spindle 1 2 is supported rotatably but unslidably in longitudinal direction in the motor-and-gear unit 30. The front end of the adjusting spindle 1 2 is screwed into the spindle nut 11 which is stationary because being retained by the anchor block 10 which is welded, on its part, to the floor 4 of the vehicle.When the adjusting spindle 1 2 is being brought in a rotating movement by means of the motor-and-gear unit 30, the adjusting spindle 1 2 will slide the frame 1 and, consequently, the whole vehicle seat in the direction of the arrow A or in contrary direction, as the sense of rotation of the adjusting spindle 1 2 may be. A special device taking care that the adjusting spindle 1 2 is not screwed out of the spindle nut 11 by the motor-and-gear unit 30, is not illustrated in detail in the drawings. Expediently, electric switches, respectively contacts are provided for that purpose at the seat frame 1 and at the floor 4 which switch off the motor in due time, that is before the adjusting spindle 1 2 comes free out of the spindle nut 11, or else, before the motor-and gear unit 30 comes into contact with the anchor block 10.

Alternatively, the motor-and-gear unit 30 may be arranged separately from the anchor bearing for the adjusting spindle at the seat frame or at the transverse strut 7, and power transmission from the unit 30 may take place through an intermediate member, for example a joint shaft.

Claims

1. A mechanism to drive a longitudinally slidable vehicle seat, with two slide railes (5, 6) arranged at the floor (4) of the vehicle and provided with slide shoes (2, 3) to support the one end of the said seat frame (1) and with a stationary anchor block (10) to support the other end of the said seat frame (1), with longitudinal rail (8) secured to the said seat frame (1) and sliding in the said anchor block (10), characterised in that parallel to and at a distance from the said longitudinal rail (8), there is provided an adjusting spindle (12) having one end supported rotatably but not slidably in the longitudinal direction (A) in a motor-andgear unit (30) coupled to the said longitudinal rail (8) and/or to a transverse strut (7) of the said seat frame (1), the said adjusting spindle (12) co-acting with a spindle nut (11) which is unslidably retained by the said anchor block (10).

2. A mechanism as claimed in claim 1, characterised in that the said anchor block (10) is provided with at least two arms or lateral members (14, 15) extending at right angles to the adjusting direction (A) and retaining the said spindle nut (11) or an adjusting nut between them.

3. A mechanism as claimed in claim 2, characterised in that the said two arms or lateral members (14, 15) of the said anchor block (10) are each furnished with an opening (17 and 19, respectively) through which the said adjusting spindle (12) passes.

4. A mechanism as claimed in claim 3, characterised in that the said spindle nut (11) is configurated as a preferably parallelepipedshaped body whose diametrally opposite frontal faces (1 lea, 1 1b) at least partly abut with the inside faces of the said arms or lateral members (14, 15), with a threaded bore (18) penetrating through both said frontal faces (ill, 1 1b) being aligned with the said openings (17, 19) in the said lateral members (14, 15) of the said anchor block (10).

5. A mechanism as claimed in claim 4, characterised in that the said two arms or lateral members (14, 15) of said anchor block (10) positioned opposite each other are arranged in intersecting planes and the said frontal faces (11 a, 11 b) of the said adjusting nut (11) are configured as corresponding inclined surfaces.

6. A mechanism as claimed in claim 4 or claim 5, characterised in that the said frontal faces (1 la, 1 1b) of said spindle nut (11) which are located diametrally opposite each other and abut with the said lateral members (14, 15) of said anchor block (10) are configured at least partly in the shape of cylindrical or conical surfaces (1 it, 1 1d).

7. A mechanism as claimed in claim 4, 5 or 6, characterised in that the said adjusting nut (11) is furnished with a projection (29) extending at right angles relative to the longitudinal axis (L) of the said threaded bore (18).

8. A mechanism as claimed in any one of claims 4 to 7, characterised in that the said spindle nut (11) is formed with a collar (16) projecting outside and encircling one of the said openings of said threaded bore (18), said collar (16) having an outside diameter sized such to render it introducible into the said opening (17) provided in the one said lateral member (14) of said anchor block (10) for the adjusting spindle (12) to pass through it.

9. A mechanism as claimed in any one of claims 4 to 8, characterised in that the distance at which the said two frontal faces (1 1a, 1 1b) of said spindle nut (11) are located relative to each other is sized such that the lateral bottom surface (ill) of said spindle nut (11) rests on the said floor (4) of the vehicle when the said frontal faces (ill, 1 1b) are in abutment with the corresponding inside surfaces of the said two lateral members (14.

15) of said anchor block (10).

10. A mechanism as claimed in any one of claims 4 to 9, characterised in that at its one said frontal face (ill), the said spindle nut (11) is provided with a recess into which a bushing preferably made of plastic material is introducible, the said bushing having a length sized such that upon its introduction into the said recess positioned coaxially relative to the said threaded bore (18), said bushing projects outside beyond said frontal face (ill) in the shape of a collar (16).

11. A mechanism as claimed in any one of claims 4 to 10, characterised in that at its one lateral face (ill) facing the said anchor block (10), the said spindle nut (11) is furnished with a rib or cam (31) with which said spindle nut (11) is in abutment against the back portion (26) of said anchor block (10).

12. A mechanism as claimed in claim 10, characterised in that the said spindle nut (11) is made of a plastic material and in that the said bushing forming said collar (16) is constituted by a metal element.

1 3. A mechanism as claimed in any one of the preceding claims, characterised in that the said motor-and-gear unit (30) is arranged separately from an anchor bearing for the said adjusting spindle (12) at the said seat frame (1) or at a said transverse strut (7) of said seat frame (1) and in that the power transmission from said motor-and-gear unit (30) takes place through an intermediate member, as for example a joint shaft.

14. A mechanism as claimed in any one of claims 1 to 12, characterised in that an anchor bearing to support and guide the said adjusting spindle (12) forms part of the said longitudinal rail (8) and in that the said motorand-gear unit (30) is positioned at the said seat frame (1).

1 5. A mechanism to drive a longitudinally slidable vehicle seat substantially as herein described with reference to and as illustrated in the accompanying drawings.