GB2151132A

GB2151132A - Mechanism for a longitudinally slidable vehicle seat

Info

Publication number: GB2151132A
Application number: GB08429595A
Authority: GB
Inventors: Ulrich Budde
Original assignee: Alfred Teves GmbH
Current assignee: Continental Teves AG and Co oHG
Priority date: 1983-12-15
Filing date: 1984-11-23
Publication date: 1985-07-17
Also published as: DE3345405C2; DE3345405A1; FR2556665B1; GB2151132B; FR2556665A1; GB8429595D0

Abstract

In a longitudinally slidable vehicle seat, the seat frame 1a is furnished with a longitudinal rail 8 arranged in the adjusting direction, which rail 8 slides in an anchor block 10, together with said frame, that is welded or bolted to the vehicle floor 4, said block 10 being provided with at least one pair of stays or lateral member 14 one side of said rail 8, with the inside faces of said members 14 extending at right angles to the adjusting direction. At the free end of its lower portion 8a which is bent off laterally, the said rail 8 is furnished with a further inclined stem 8b which is at an acute angle relative to the said portion 8a and extends down into the one lower corner of a channel 34 having a rectangular cross-section. Rail 8 is thus movable inside the anchor block without play and, in case of accident, locks by itself against sliding out of the block. <IMAGE>

Description

SPECIFICATION Mechanism for a longitudinally slidable vehicle seat The invention is related to a mechanism for a longitudinally slidable vehicle seat, with two slide rails positioned parallel to each other and located at a floor of a vehicle or at a seatframe, with slide shoes to supportthe one end ofthe seatframe and with a stationary anchor block to retain the other end of the seat frame, with a longitudinal rail, secured to the seat frame, extending in the adjusting direction and sliding in the anchor block, the anchor block being provided with two webs which jointly form a slot to serve as a guide for a vertically arranged portion of the longitudinal rail, and the two webs of the anchor block being flared out in the area ofthefloor ofthe vehicle so as to form a frame-shaped channel surrounding the lower longitudinal edge ofthe longitudinal rail.

Vehicle seats are known in which the frame of the vehicle seat is retained and guided with each of its rear ends in rails secured to the floor ofthe vehicle, the front end of the seat frame sliding in one single anchor block at the floor ofthe vehicle for which purpose a longitudinal rail extending in the adjusting direction is fastened 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 these two pairs of stays, the anchor block is, furthermore, provided with a roughly L-shaped recess which extends in the sliding direction and in which the longitudinal rail slides, which latter is rigidly coupled to the seat frame.To this end, the longitudinal rail isfurnished at each of its upper and lower longitudinal edges with a respective lateral guide face or stem bent off rectangularly, 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 support at the anchor block to prevent the rail from rattling in its guide in the anchor block. Adjustment ofthe 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. In case of a collision of the vehicle, the locking mechanism moreover prevents that the longitudinal rail is torn out of the anchor block.

The present invention has for an object two configure the longitudinal rail ofthe seat frame in such a manner that it is movable inside the anchor block virtually without play. In addition, the longitudinal rail should be formed such that in case of a vehicle accident it locks by itself against sliding out of its guide in the anchor block, so that any specific locking mechanism is superfluous and the vehicle seat may be provided with a motor-driven adjusting mechanism.

According to the present invention there is provided a mechanism fora longitudinal slidable vehicle seat, with slide rails positioned parallel to each other and located at a floor of a vehicle or at a seat frame, with slide shoes to supportthe one end of said seat frame and with a stationary anchor block to retain the other end of said seat frame, with a longitudinal rail, secured to said seatframe, extending in the adjusting direction and sliding in said anchor block, said anchor block being provided with webs which jointly form a slot to serve as a guide for a vertically arranged portion of said longitudinal rail, and said webs of said anchor block being flared out in the area of said floor of the vehicle so as to form a frame-shaped channel sur rounding the lower longitudinal edge of said longitudinal rail, characterised in that the said longitudinal rail has a multiple-stem cross-section, with a lug or stem inclined toward said vehicle floor being formed at a lower portion of said longitudinal rail which is bent off laterally, which said inclined lug orstem forms an acute angle with that said lower portion of the said longitudinal rail which is bent off laterally, with the vertically arranged portion of said longitudinal rail in conjunction with said lower laterally projecting portion including an anglewhich issmallerthana right angle.

The longitudinal rail has a roughly L or Z-shaped cross-section.

Preferably, the inclined stem is formed at the free end ofthe lower portion standing offlaterallyfromthe vertically arranged portion, the lowerfree edge of that inclined stem ending approximately in the plane in which the vertically arranged portion of the longitudinal rail extends.

Advantageously, the plane in which the inclined stem of the longitudinal rail extends roughlyconstitutes one ofthe diagonals ofthe roughly rectangular channel which is formed by the two webs ofthe anchor block.

In orderto absolutely safeguard a deformation of the longitudinal rail in the event of an accident, the longitudinal edge which is formed jointly between the inclined stem and the lower laterally bent off portion abuts both with a perpendicular part of the wall ofthe channel defined by the lateral members of the anchor block and with an upper part ofthe wall of the channel which extends in horizontal direction.

An embodiment ofthe invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure lisa top plan view of the frame of a vehicle seat with an adjusting mechanism driven by an electric motor, in a strongly scaled-down and simplified representation; Figure 2 is a view, partly in cross-section, ofthe seat of an automotive vehicle as per Figure 1,viewed along the longitudinal direction of its longitudinal rail and in a scaled-up representation as compared to that in Figures; Figure 3 is the front view, partly in cross-section, of the anterior anchor block of the vehicle seat; Figure 4 is a side view ofthe front anchor block ofthe vehicle seat of Figure 1;; Figure 5 is atop plan view of the front anchor block of the vehicle seat of Figure 1, and Figure 6 is a cross-section ofthe longitudinal rail which is secured to the vehicle seat and which is retained and guided in the anchor block as shown in Figures 1 to 5.

As shown in Figure l,theframe 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 ofthe arrow A in a rail 5, respectively 6, which is rigidly securedtofloor4 of the vehicle. The frame 1 provided with a transverse strut 7 which is, in is turn, rigidly coupled with the front portion 1 a ofthe frame 1 by means of a longitudinal rail 8 which isslidably retained and guided in an anterior stationary -.nchor block 10 with a sliding pad 9 (Figure 2) being interposed in between.In the anchor block 10, there is supported a spindle nut 11 with which an adjusting spindle 12co-acts,with one end of the adjusting spindle 12 being supported in a gear witch motor13 (motor-and-gear unit) in such a manner that the adjusting spindle 12 is rotated when the motor is switched on and the stationarily retained spindle nut 11 movestheframe 1 in the direction of the arrow A or in contrary direction (depending on the sense of rotation ofthe adjusting spindle 12).

The spindle nut 11 is configured as a separate element having a shape and size so as to allow the spindle nut 11 to fit exactly between the two lateral members 14 and 15 ofthe anchor block 10. Forthe introduction ofthe spindle nut 11 into the anchor block 10, first of all a collar 16 provided at the one frontal (end) face of the spindle nut 11 is inserted (in the direction ofthe arrow B) into the opening 17 provided in the lateral member 14 and subsequently the other end of the spindle nut 11 is introduced with its frontal (end) face into the anchor block 10 in the direction of the arrow C where it abuts with the inside surface of the lateral member 15 in such a way thatthe opening 19 ofthe lateral member 15 comes to be aligned with the threaded bore 18.After the adjusting spindle 12 is screwed into the threaded bore 1 8 of the spindie nut 1 1,the latter is firmly retained between the lateral members 14,15 ofthe anchor block 10, as a result whereofupon rotating the adjusting spindle 12, the latter is movable together with the frame 1 of te vehicle seat relative to the floor4 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 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 ofthe lateral members 14, 15 and 20,21, respectively which are directed toward the dished floor 4 of the vehicie are each welded to the floor 4 of the vehicle.Through a perpendicular web 26 Fssi- tioned parallel to the longitudinal rail 8, a web 27 running parallel to thefloor4, theweb 33, and 3 bridge portion 28, the four lateral members 14, 15,20,21 are connected with one anotherto form one single element.

The spindle nut 11 retained by the anchor block 10 is configurated as a substantially parallelepiped-shaped body whose frontal (end ) faces located opposite each other are partly rounded offorconfigured as halves of conical surfaces running obliquely relative to the top side and to the bottom side. In addition, the spindle nut 11 is furnished with a lateral projection 29 which facilitates the introduction of the spindle nut 11 1 into the anchor block 10 and prevents the spindle nut 11 from rotating about the longitudinal axis L of the threaded bore 18. The collar 16 is configured as a separate ring or bushing made of a plastics material which is fastened button-wiseinthethreaded bore 18.

The collar 16 projects beyond the frontal face of the spindle nut 11 just sufficently so asto be firmly seated in the opening 17 which is provided in the lateral member 14. In case the adjusting spindle lifa ls to run perfectly parallel to the longitudinal rail 8fastenedto the frame 1 of the vehicle seat or in case during its slide in the direction indicated by the arrow A, the frame 1 failsto move in parallel direction relative to the two rails 5 and 6 being rigidly fixed to the floor4, the spindle nut 11 may exercise a slight tumbling movement about its support at the collar 16 since the opening 19 inthe lateral member 15 isslighly oversized relativetothe external diameter of the adjusting spindle 12.

At the rear end of the seat frame 1 of the vehicle seat, there is arranged the motor-and-gear unit 13 which is bolted or riveted to the frame 1 at the end of the longitudinal rail 8 in the area of the transverse strut 7.

The one end of the adjusting spindle 12 is supported rotatably but unslidably in longitudinal direction in the motor-and-gear unit 13. The front end ofthe adjusting spindle 12 is screwed into the spindle nut 11 which is rigid because of being retained bythe anchor block 10 which is welded, on its part, to the floor4 ofthe vehicle. When the adjusting spindle 12 is being brought in a rotating movement by means of the motor-and-gear unit 13, then underthe action of the motor-and-gear unit 13, the adjusting spindle 12 will slide the frame 1 and, consequently, the whole vehicle seat in the direction ofthe arrow A or in contrary direction, as the sense of rotation ofthe adjusting spindle 12may be.A special device taking care that the adjusting spindle 12 is not screwed outofthespindle nut 11 by the motor-and-gear unit 13, is not illustrated in detail in the drawings. Expediently, electric switches, respectively contacts are provided forthat purpose at the seatframe 1 and atthefloor4which switch off the motor ofthe motor-and-gear unit 13 in due time, that is before the adjusting spindle 12 comes out ofthe spindle nut 11, or else, before the motor-and-gear unit 13 comes into contact with the anchor block 10.

As is revealed by Figure 6, the cross-section of the longitudinal rail 8 is roughly Lor Z-shaped, with a lug or stem 8b being formed at the lower portion 8a bent off laterally, said lug or stem 8b including an acute angle a of, for example, 120 with that portion 8a of the longitudinal rail 8 which is bent off laterally. The stem 8a bent off laterally, on its part, inciudes an angle of less than 90 (for example 65") with the perpendicular portion 8c.The portions 8a, 8b, 8cwhich are bent Z-shape as described above fiil the slot 32 between the webs 26 and 33 and the frame or channel 34 having a rectangular cross-section so that the longitudinal rail 8 furnished, in addition, with a portion 8d at its upper edge which is bent off at right angle and which serves to fasten the longitudinal rail 8 to the seatframe 1 and to guide the longitudinal rail 8 on the sliding pad 9, is noiselessly movable in the anchor block 10.

In order to firmly anchor it in the anchor block 10, the rail 8 is configured in such a manner that it maytouch the anchor block 10 exclusively in point D upon an impact. In this way, the lever arm for a fixation weld at 24,25 is kept as small as possible.

Due to the occurring upwardly directed forces of the seat frame 1,the lower end 35 ofthe sectional rail 8will get wedged atthe one side ofthe channel 34 and will prevent a further upward bend ofthe sectional rail. In most ofthe cases, the seatwill therefore no longer be torn out ofthe anchor block 10 in case of an accident.

It is a major advantage ofthe described vehicle seat that it meets the impact regulations without any additional locking.

The known-art longitudinal rails had a Z-shaped cross-section and were locked to the anchor block through the vertical web by means of bolts. This known design fails, however, to stand the safety tests without being equipped with bolts and a locking mechanism. That locking mechanism cannot, however, be employed in seats which are driven electrically.

Applying the version of the longitudinal rail (8, 8a, 8b, 8c) described in the foregoing both types of seats, that is the one locked mechanicaily and the one driven electrically, can be mounted in the vehicle without any modification tothe carfloor.

Claims

1. A mechanism for a longitudinally slidable vehicle seat, with slide rails (5,6) positioned parallel to each other and located at a floor (4) of a vehicle or at a seat frame (1), with slide shoes (2,3) to supportthe one end of said seat frame (1) and with a stationary anchor block (10) to retain the other end (1 a) of said seat frame (1), with a longitudinal rail (8), secured to said seatframe (1 a), extending in the adjusting direction (A) and sliding in said anchor block (10), said anchor block t10) being provided with webs (26,33) which jointlyform a slot (32) to serve as a guidefor a vertically arranged portion (8c) of said longitudinally rail (8), and said webs (26,33) of said anchor block (10) being flared out in the area of said floor (4) ofthe vehicle so as to form a frame-shaped channel (34) surrounding the lower longitudinal edge (35) of said longitudinal rail (8), characterised in that the said longitudinal rail (8) has a multiple-stem cross-section, with a lug or stem (8b) inclined toward said vehicle floor (4) being formed at a lower portion (8a) of said longitudinal rail (8) which is bent off laterally, which said inclined lug orstem (8b) forms an acuteangle (cox) with that said lower portion (8a) of the said longitudinal rail (8) which is bent off laterally, with the vertically arranged portion (8c) of said longitudinal rail (8) in conjunction with said lower laterally projecting portion (8a) including an angle ((3) which is smailerthan a right angle.

2. A mechanism as claimed in claim 1, characterised in thatthesaid inclined stem (8b)isformedatthe free end (D) ofthe said lower portion (8a) which is bent off laterally from the said vertically arranged portion (8c), a lower free edge (35) of said inclined stem (8b) ending approximately in the plane in which the said vertically arranged portion (8c) of said longitudinal rail (8) extends.

3. A mechanism as claimed in claim 1 or claim 2, characterised in that the plane in which the said inclined stem (8b) of said longitudinal rail (8) extends roughly constitutes one of the diagonals of said channel (34) which has a roughly rectangular crosssection and is formed bythe said two webs (26) and (33).

4. A mechanism as claimed in any one of claims 1 to 3, characterised in that a longitudinal edge (D) which is formed jointly by the said lower portion (8a) with the said inclined stem (8b) of said longitudinal rail (8) abuts with both a perpendicular part (36) of the wall of said channel (34) defined by the lateral members (20,21) of said anchor block (10) and with an upper part (37) ofthe wall of said channel (34) which extends in horizontal direction.

5. A mechanism for a longitudinal slidable vehicle seat as claimed in claim 1 and substantially as herein described with reference to the accompanying drawings.