Chairs and seats – Bottom or back – Framework
Patent
1985-04-04
1987-01-20
Zugel, Francis K.
Chairs and seats
Bottom or back
Framework
297455, 297459, A47C 702
Patent
active
046376518
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a seat plate for supporting the pelvis of a person sitting on a seat, e.g. a vehicle seat.
To enable comfortable sitting attitudes in vehicles and in furniture for sitting, it is generally known to form seats for persons with soft and elastic upholstery. In an unloaded state, such a seat usually assumes a substantially smooth surface, while under the load of a person it accommodates its shape after the contours with which the person in question loads the seat. This results in that the weight of the person is taken up by a comparatively large contact area. However, there is no notable support for the person in a horizontal direction, with the result that the person must activate certain muscles in order to sit in an upright attitude. Such a sitting attitude is however not possible to maintain for a long time, since the muscles tire rapidly.
In seats with back supports it is common for a person sitting on one to sit leaning somewhat backwards. However, this results in that the pelvis successively glides forward and/or causes rotation of the pelvis about a horizontal axis. This rotation takes place substantially about an imagined axis extending through the joints of the hip-bone in the pelvis, to give rise to what is usually called "pelvis rotation".
The problems mentioned result in that the skeleton and musculature of the sitting person are subjected to skew loads. The consequence is feelings of discomfort which usually occur in the form of tiredness and soreness.
The above-mentioned problems are particularly salient in vehicle seats, since a person sitting on such a seat is subjected to alternating accelerations and retardations during travel. Furthermore, such a person is also subjected to lateral forces striving to laterally displace the pelvis and to turn the pelvis about a vertical axis.
There are also similar problems for people in wheelchairs, who are often compelled to sit for long periods in an unaltered attitude.
With the intention of solving the above-mentioned problems, it is known to form the sitting portion of such seats with a U-shaped depression having the legs of the U directed forwards. Such a depression is intended to support the pelvis and to prevent its sliding forwards by having the pubic bone of the person being supported against a forward protuberance. However, this is a drawback since at least male persons experience this implementation as directly uncomfortable. Neither does the U-shaped depression prevent rotation of the pelvis, with the consequence that skew loads also occur. The U-shaped depression is defined laterally by raised edges, which give rise to high contact pressures, inter alia, on the sciatic nerves. This results in that the legs are subjected to discomfort in the form of numbness and sensations of cold.
The present invention has the object of forming a seat plate positioning the pelvis better than known solutions both with respect to gliding and to turning, without causing high contact pressure against nerves or muscles. In this respect the invention is distinguished substantially in that the seat plate is formed on its upper side with two raised scythe-shaped ridges, symmetrically situated relative a longitudinal centre line, and in that each ridge includes a substantially transverse ridge portion which extends outwards and curves slightly backwards, and a substantially longitudinal ridge portion which extends backwards and slightly curves outwards, the ridges being contoured to support the seat bone protuberances of the pelvis substantially on their forward and inner sides.
A seat plate formed in accordance with the invention positions the pelvis in all directions by the seat bone protuberances resting against the mentioned ridges on the seat plate. The seat bone protuberances are the lower parts of the hip-bone on which the pelvis rests when a person sits on a flat, hard substructure. The centre-to-centre distance between the seat bone protuberances is practically the same for all people irrespective of bodily build. It is thus pos
REFERENCES:
patent: 1455234 (1923-05-01), Thompson
patent: 2769185 (1956-11-01), Biederman
patent: 3177036 (1965-04-01), Halter
patent: 3205010 (1965-09-01), Schick
patent: 3376070 (1968-04-01), Johnson
patent: 3463547 (1969-08-01), Brennan et al.
patent: 3495871 (1970-02-01), Resag et al.
patent: 3503649 (1970-03-01), Johnson
patent: 3749442 (1973-07-01), Berg et al.
patent: 3751111 (1973-08-01), Taylor et al.
Brown Peter R.
Saab-Scania Aktiebolag
Zugel Francis K.
LandOfFree
Seat plate does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Seat plate, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Seat plate will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2131702