Chairs and seats – Bottom or back with means to alter contour
Reexamination Certificate
1999-03-01
2001-07-03
Cuomo, Peter M. (Department: 3636)
Chairs and seats
Bottom or back with means to alter contour
C297S284100, C297S284200
Reexamination Certificate
active
06254186
ABSTRACT:
This application is the national phase under 35 U.S.C. §371 of prior PCT International Application No. PCT/AU97/00480 which has an International filing date of Jul. 30, 1997 which designated the United States of America.
This invention relates to lumbar supports for use in the backrest of seats, chairs and the like. The invention is especially suited for use with vehicle seats, and it will be convenient to hereinafter describe the invention with particular reference to that example use. In that regard, the word “vehicle” is to be understood as embracing vehicles of all kinds including aircraft, waterborne vehicles and land vehicles.
It is well known to provide adjustable lumbar supports in vehicle seats, and especially in the seat to be occupied by the vehicle driver. Such adjustable supports take a variety of forms, and the manner of achieving adjustment also varies widely. The adjustment is generally such that it varies the effective length of the support and/or its stiffness, and thereby influences the extent to which the support curves rearwards in response to pressure applied by the user of the vehicle seat. That is, the support may provide a relatively flat or a deeply curved support for the vehicle seat occupant, according to the level of adjustment of the effective length of the support.
Adjustment of the foregoing kind is sometimes referred to as fore and aft adjustment, which reflects the direction in which the central part of the support moves during adjustment under normal use conditions.
Adjustment of the effective length of the lumbar support requires drive means, which may be power driven (e.g., electric) or manually driven. In either case, an actuator is required and that is generally mounted on the seat frame or other support structure, and is connected to the lumbar support through a suitable drive connection. Separate mounting of the actuator and the lumbar support adds to the inconvenience and cost of installing the lumbar support assembly.
Another problem encountered with lumbar supports as are currently available, is the need to impose relatively high forces in order to adjust the lumbar support from a deeply curved condition towards a relatively flat condition. The magnitude of the force required increases as the lumbar support flattens.
It is an object of the present invention to provide an improved lumbar support assembly in which at least part of the drive means for causing adjustment of the lumbar support is mounted on the lumbar support prior to attachment of that support to a seat frame. It is a further object of the invention to provide an improved lumbar support which minimises the forces necessary to adjust the support towards a relatively flat condition.
According to one aspect of the present invention, there is provided a lumbar support for use with the backrest of a seat, said support including, an elongate band having a first end and a second end and a front load bearing surface located between said ends, each said end being connectable to a respective one of two sides of said backrest between which the band extends when in use, drive means connected to said band and being operable to vary the longitudinal tension in the band, said load bearing surface having a rearward curvature between said ends at least when said tension is relatively low, and a plurality of pleats located between said first and second ends, each said pleat forming part of said band and being responsive to said variation in tension so as to fold or unfold and thereby vary said rearward curvature.
In one form, the band includes a strap member which in use extends between two spaced sides of the backrest, and a shield member which overlies at least part of a front surface of the strap member and which extends forwardly from that surface by a variable distance. The two members interact so that the aforementioned distance increases in response to movement of the strap member towards a tensioned condition and decreases in response to movement of the strap member towards a relaxed condition.
The reference to “strap member” in the preceding and following passages of this specification is to be understood as embracing any elongate member having a degree of flexibility such that it can be bent or straightened as required. The strap member may comprise a single strap or the like, or it may comprise a plurality of straps or the like arranged side by side. Furthermore, the reference to “relatively flat” is to be understood as embracing situations in which the strap member is not completely flat or straight between its ends, but has a degree of rearward curvature which is shallow by comparison with the rearward curvature adopted in the relaxed condition of the strap member.
In a preferred arrangement the shield member includes or is composed of a concertina-like section having a plurality of pleats or folds each of which extends generally transverse to the longitudinal axis of the strap member. The crest of each pleat or fold can be relatively sharp or blunt according to requirements, and the outer surface of each crest can be Telatively flat or curved as required, in either the longitudinal direction of the crest or a direction transverse thereto. For convenience of description each pleat having its crest located forwardly of the front surface of the strap member will be referred to as a rib, and each intervening pleat will be referred to as a valley: The base of each valley may have a transverse cross-sectional shape corresponding to that of the crest of each rib, but that is not essential.
The concertina-like section is preferably arranged so that the base of at least some of the valleys are supported directly or indirectly by the front surface of the strap member. It will be apparent that the crest of each rib is spaced forwardly and outwardly from that front surface. The arrangement is such that variation in the longitudinal extent of the concertina-like section causes a variation in the depth of that section, which is the distance between two planes one of which contains the crests of the ribs and the other of which contains the bases of the valleys.
When a lumbar support of the foregoing kind is installed for use the ribs and the valleys of the concertina-like section extend in a direction which is generally consistent with the direction in which the associated seat backrest extends upwardly from the seat base. The arrangement is such that the depth of the concertina-like section increases in response to increased tension in the strap member and as a result two mechanisms combine to produce a firmer support for the back of a person occupying the associated seat. One mechanism is the flattening or straightening of the strap member, and the other is the increase in front to back depth of the concertina-like section.
In a variation of the lumbar support described above the band does not involve separate strap and shield members as described, but includes a plurality of relatively rigid elements which are spaced apart in the longitudinal direction of the band, and at least one pleat is located between and interconnects each two adjacent elements. The pleats respond to changes in longitudinal tension in the band by expanding or collapsing laterally and thereby changing the lateral spacing between adjacent elements. Such a change in spacing causes a change in the effective length of the band and thereby alters the rearward curvature of the band.
A lumbar support according to the invention can be adjusted by any appropriate drive means. In one arrangement the drive means is electrically operated and is combined with the lumbar support band to form an assembly which can be attached to and removed from the backrest of a seat as a single unit.
The drive means may include a screw threaded spindle and nut system which is operative to adjust the longitudinal tension in the lumbar support band and thereby adjust the depth of rearward curvature of that band. An electric motor may be operatively connected to the screw threaded spindle through a worm and worm wheel connection. A particularly c
Birch & Stewart Kolasch & Birch, LLP
Cuomo Peter M.
Henderson's Industries Pty Ltd
White Rodney B.
LandOfFree
Adjustable lumbar support does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Adjustable lumbar support, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adjustable lumbar support will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2562964