AU598682B2

AU598682B2 - Seat adjustment mechanism

Info

Publication number: AU598682B2
Application number: AU18166/88A
Authority: AU
Inventors: John Douglas Gerisch
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-06-18
Filing date: 1987-06-18
Publication date: 1990-06-28
Anticipated expiration: 2008-06-20
Also published as: AU1816688A; WO1990005251A1

Description

4 COMMONWEALTH OF AUSTRALIA PATENTS ACT, 1952 COMPLETE SPECIFICATION FOR OFFICE USE Short Title: Int. C1.

This document contains the amendments made under Application Number: Section 49 and is correct for Lodged: printing, Complete Specification Lodged 0 o Accepted: ,Oo Lapsed:

S

s e Published: 4 0 Priority: Relared Art: TO BE COMPLETED BY APPLICANT 4 Name of Applicant: John Douglas Gerisch Address of Applicant: 15 St. George Crescent SANDY POINT N.S.W. 2170 i Actual Inventor: John Douglas Gerisch SAddress for Service: ANDERSON-TAYLOR ASSJCIATES, Registered Patent and Trade Mark Attorneys of Harrison Avenue BONNET BAY, N.S.W. 2226 Complete Specification for the invention entitled: SEAT ADJUSTMENT MECHANISM The following statement is a full description of this invention including the best method of performing it known to me:- This invention relates to an adjustment mechanism for seats inrluding those used in motor vehicles.

Such seats in addition to being movable in the forward and backward direction often include means for varying the height of the bottom cushion and/or the tilt angle of the back. with the latter two adjustments however a substantial mechanical advantage is required as the seat normally carries the full weight of the user while it is being moved.

Also the motor vehicle design rules severely limit the amount of play and creep allowed in the seat mountings as well as requiring that they be able to withstand the substantial impact loadings that could occur in a crash.

It is an object of this invention to provide a mechanism which fulfils the above criteria better than existing devices and moreover can be produced at relatively low cost.

Broadly this invention discloses a mechanism for adjusting a motor vehicle seat or the like comprising a base with a S° rack slidable therein through engagement with a rotatable scroll plate, said base and rack being adapted for ii attachment to tkd adjustable frame members of the seat in a manner whereby adjustment thereof is obtained by rotation of said scroll plate.

The currently preferred embodiments of this invention will now be described with reference to the attached representations in which: -2- Figure 1 shows a plan view of one form of the aforementioned mechanism, Figures 2 and 3 show side and end views of the mechanism of figure 1, Figure 4 shows a plan view of the base and rack with the scroll plate removed Figure 5 shows the undersi of the scroll plate, Figures 5A and 5B show modifications of the mechanism Figure 1, Figures 6 and 7 show the mechanism installed on a motor vehicle seat, and Figure 8 shows a second embodiment of the ta invention.

Referring first to figures 1 to 3 the device comprises a base 1, a slidable rack 2 which seats in a channel 3 in said base, keeper plates 4 and 4a which embrace the rack and a scroll plate 5 which is rotatably mounted on a pivot pin or bolt 6 in said base. A spoked wheel 6A is also fixed to the upper face of the scroll plate to assist in operating the device as described later.

The rack 2 has a series of transverse treth 7 formed i.n its upper surface which are adapted to mate with the scroll thread 7A on the underside of the plate 5. The teeth 7 are therefore shaped in a manner whereby the outer -3- .__111 yL~-~-rr; edges 8 conform to the smallest diameter of the scroll thread 7A and the inner edges 8A to the largest thread diameter on the plate. The rack is thus movable in either the inward or outward direction (see arrow A) by appropriate rotation of the plate 5. Indeed the arrangement shown has been found to provide an exceptionally smooth and precise action with nly a minimum of play. Further, the mechanism is virtual y creep free so that adjustment is maintained even when subjected to the vibrations and cyclic loadings encountered in motor vehicle seats.

As best shown in figure 4 the inner end of the rack 2 may also have a cutout 8B to accomodate the bolt shaft 6 when t 6 in its withdrawn position.

0.o A modified form of this mechani-sm is shown in cross-sectional views by figures 5A and 5a. In this case the underside 8C and axis of rotation 8D of the scroll plate are offset by an angle D of 2 degrees with respect to the rack 2. This allows o a oa.. the rack to clear the scroll plate on one side as o o illustrated. Unlimited movement of the rack is therefore obtained without significantly alterinq the .external shape or design of the unit as the center line of the hcusing remains square to the diameter of the scroll plate. The scroll plate may be either exposed and driven by a handwheel 6A or enclosed and operated via a shaft 8 Two specific applications of this mechanism to a motor vehicle seat are shown in figures 6 and 7. In the first -4example the base 1 is attached by means of boils or the like to the main seat frame 9 and the rack i8 attached via link 10 to a reclinable seat back 11 below it5 pivot point 12,, Rotation of the handle 6A thus serves to adjust the seat back between a reclined and upright position as shown by arrow B. In the second example the base is again attached to the main seat frame 9 however the rack is now connected to the forward member 13 of a four bar linkage system which supports the seat. Rotation of handle 6A therefore adjusts the angle of this member 13 with the result that the height of the seat is varied as shown by arrow C.

Although not shown in figures 6 and 7 it is also envisaqed that a pair of rack and scroll plate mechanisms (for example of the type shown in figure 5C) could be fitted one on each side of the seat to provide added strength and support. Preferably they would be aligned so as to be driven through said shaft 8E from one side of the seat to the other.

Figure 8 shows a third embodiment of the mechanism in which a circular rack 14 with teeth 14A is provided to mesh with the scroll plate 15. Although not illustrated it is envisaged that this arrangement could similarly be used as an adjustment device for a motor vehicle seat.

For example the rack plate 14 could be incorporated directly into (,he pivot of the seat back so that rotation of the scroll plate 15 (mounted on the main seat frame) would achieve the required movement without any intervening mechanical linkage.

It will thus be appreciated that this invention at least in the form of the embodiments described provides a novel and unique improvement in adjusting mechanisms for motor vehicle seats. Clearly however the particular apparatuses disclosed are only the currently preferred forms of this invention and a wide variety of modifications may be made which would be apparent to a man skilled in the art to adapt the concept to any other installation where a precise O° ar~d stable mechanical adjustment is required. For example the shape and configuration of the rack teeth and scroll plate could be varied according to application and/or o p design preference. In addition the relative positions of 0 the scroll plate and rack on the seats could be reversed while obtaining the same mechanical effect. As mentioned earlier the strength of such arrangements could also be improved by using the mechanism on both sides of the seat with a common drive shaft therebetween. The scroll plate and rack may even be incorporated directly into the seat frame and/or may be also adapted for lumbar adjustment thereof. Finally, although the preferred embodiments are machined from steel this invention is not restricted to any particular material or mode of construction.

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Claims

1. A mechanism for adjusting a motor vehicle seat or the like, said mechanism comprising a base with a rack slidable therein through engagement with a rotatable scroll plate said base and rack being adapted for attachment to t4le adjustable frame members of the seat in a manner whereby adjustment thereof is obtained by rotation of said scroll plate. o n

2. The mechanism as claimed in claim 1 wherein the rack has a series of transverse teeth formed in the upper surface thereof which are adapted to mate with a thread on the underside of said scroll plate. o O (3

3. The mechanism a5 claimed in claim 2 wherein said rack comprises an elongated bar. 0o (0

4. The mechanism as claimed in claim 3 wherein the under- oo side and axis of rotation of said scroll plate are offset 0 with respect to the rack whereby said rack clears the scroll plate on one side for extended movement thereof.

The mechanism as claimed in claim 4 wherein the scroll plate is driven by a handwheel.

6. The mechanism as claimed in any one of claims 1 to in combination with a reclinable motor vehicle seat. -7-

7. The mechanism as claimed in any one of claims 1 to in combination with a height adjustable motor vehicle seat.

8. The combination as claimed in claim 6 or 7 wherein a pair of said mechanisms are fitted one to each side of said seat and are driven from a common shaft.

9. A mechanism for adjusting a motor vehicle seat, sdid 1; o mechanism being substantially as described herein with reference to the drawings. S dated this /7 day of 74w 1988 a0 0 John Douglas Gerisch By his Patent Attorney MICHAEL ANDERSON-TAYLOR -8-