Back support improvement

Chairs and seats – Movable back

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C297S411360

Reexamination Certificate

active

06276757

ABSTRACT:

This invention relates to a back support and, in particular, to a back support for a chair which is able to be of adjustable height with respect to an upright supported by the chair.
BACKGROUND OF THE INVENTION
An object of this invention is to propose a chair back support improvement which is at least different from those that have hitherto been provided and therefore provides a useful alternative for those wishing to purchase such units.
BRIEF SUMMARY OF THE INVENTION
In one form of this invention there is proposed a chair back support arrangement including an upright to be supported by a chair base and a back support adapted to slidably engage the upright, and interlocking means to maintain a selected support height for the back support, the interlocking means including a rack either affixed to or being part of the upright, an engaging member supported by the back support and arranged to assume either of two positions, one of which is to interlock with the rack, and the other of which is to be clear of the rack, and means to change the position of the engaging member from one of said positions to the other which means are able to be activated to effect such change by relative positioning of the back support with respect to the upright.
The purpose is to provide for an adjustable support for the back relative to the upright where the adjustment can be achieved without necessarily having an external lever or button so that it is the relative position of the two parts that will effect control of the engaging member and enable an adjustment of the height of the back support appropriately thereby.
In preference, there is a catch supported by the support back the position of which can be caused to change by relative positioning of the back support with respect to the upright so that in one position, it can catch and hold in a non-engaging position, the engaging member clear of the rack, and in another position, it will release such engaging member to effect an interengaging action with the rack.
In preference, the catch is a member pivotally supported by the back support and arranged so that when the back support is moved to a first end position, there is an interengaging between the catch and the upright whereby to effect an opening of the catch position to allow the engaging member to be released to resume an interengaging or interlocking position with respect to the rack.
In preference, in respect of a further end position of the back support with respect to the upright, the engaging member is caused by reason of an interengaging of a portion of the upright with respect to the engaging member, to be pushed into a position in which it is clear of an interengaging or interlocking position with respect to the teeth but also is further located so as to interlock with the catch member.
In preference, the catch member is urged toward a catching position by reason of a resilient member extending between the catch member and the back support.
In preference, the engaging member has interengaging teeth which are adapted to interengage with the teeth on the upright and which are respectively shaped so that the engaging member will allow for relative movement of the engaging member and therefore the back support to which it is attached, with respect to the upright in one direction but not the other.
By having the respective teeth having an inclined bias, such that when the engaging member with its teeth interengaging with the teeth of the rack are pulled in one direction, there will be a relative sliding effect urging the teeth out of an engaging position but holding tight against the edge of the rack to the next tooth.
There is therefore in effect a ratchet like arrangement which allows for the back support and of course any back supported by the back support to move under this ratchet effect in one direction even when the engaging member is in an engaging or interlocking position.
To enable a reverse relative positioning however, it would then be necessary to proceed to an end position in which the engaging member is pushed out further to a stage where it will be captured by the capture member and held in a fully clear of interlocking relationship with the rack then until the back support is moved to the further end position where there is a release shape on the capture member which will push the capture member into a further position releasing the engaging member.


REFERENCES:
patent: 4384742 (1983-05-01), Wisneiwski
patent: 4639039 (1987-01-01), Donovan
patent: 4660885 (1987-04-01), Surh et al.
patent: 4749230 (1988-06-01), Tornero
patent: 5324096 (1994-06-01), Schultz
patent: 5586809 (1996-12-01), Szmadzinski
patent: 5649741 (1997-07-01), Beggs
patent: 5664842 (1997-09-01), Tseng
patent: 5685609 (1997-11-01), Miotto
patent: 5695249 (1997-12-01), Lotfi
patent: 5725278 (1998-03-01), Verbeek
patent: 5735577 (1998-04-01), Lin
patent: 5765920 (1998-06-01), Lai

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Back support improvement does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Back support improvement, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Back support improvement will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2459489

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.