Seat occupancy sensor unit at a lower B-surface side of a seat cushion

摘要

A B-surface seat occupancy sensor unit (10) comprises a support plate (12) having a top surface (20) and a bottom surface, a plurality of spacer elements (14), which define an upper surface (18) of the unit. The top surface of the support plate is arranged recessed the upper surface. A first foam pad (22) is disposed between the spacer elements on the support plate. A recess (24) formed in the top surface of the support plate, underneath the first foam pad, accommodates a second foam pad (23) carrying a pressure-responsive membrane switch (26). The recess has a depth exceeding the total height of the pressure-responsive membrane switch and the second foam pad. The pressure-sensitive membrane switch projects laterally beyond opposite edges of the second foam pad.

主权项

1. A B-surface seat occupancy sensor unit for detecting an occupancy state of a seat, comprising
a support plate having a top surface and a bottom surface, a plurality of bearing elements for fixation of said support plate on seat cushion suspension springs, said bearing elements defining an upper surface of said B-surface seat occupancy sensor unit, which said top surface of said support plate is arranged recessed from; a first foam pad disposed between said bearing elements on said support plate; a recess formed in said top surface of said support plate, underneath said first foam pad; a second foam pad arranged in said recess; a pressure-responsive membrane switch arranged in said recess on said second foam pad, said pressure-responsive membrane switch comprising a first carrier film and a second carrier film spaced from each other by a spacer film, said spacer film having therein an opening defining a cell, said pressure-responsive membrane switch comprising at least two electrodes arranged in facing relationship with each other in said cell on said first and said second carrier film, respectively, in such a way that they are brought closer together, possibly into contact with each other, when pressure is applied on said pressure-responsive membrane switch; wherein said recess has a depth exceeding the total height of said pressure-responsive membrane switch and said second foam pad; and wherein said pressure-sensitive membrane switch projects laterally beyond a first edge of said second foam pad and beyond a second edge of said second foam pad, opposite said first edge.