Pressure sensitive switch
Patent 4172216 Issued on October 23, 1979. Estimated Expiration Date: 
May 19, 1998. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
May 19, 1998. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References RE28754 2260715 2818477 3487451 3715541 3830991 3879586 Hermetically sealed keyboard type assembly with elastomeric electrical connecting link between switch and component modules Keyboard arrangement having after-control signal detecting sensor in electronic musical instrument Patent #: 3960044 InventorAssigneeApplicationNo. 05/907532 filed on 05/19/1978US Classes:200/85R, WEIGHT200/511, Compressible elastomer200/512, Membrane type200/86R, Treads338/114, Deformable340/666WeightExaminersPrimary: Tolin, Gerald P.Attorney, Agent or FirmInternational ClassesH01H 3/14 (20060101)H01H 3/02 (20060101) AbstractA resilient insulative layer of a plastic foam material is sandwiched between a dimpled carbon powder loaded plastic sheet and a resilient carbon powder loaded plastic foam pad. The dimples extend part way through holes provided therefor in the insulative layer. This sandwich assembly being placed under a bed mattress serves as a mattress-switch indicating electrically by contact between the sheet and the pad the presence of an occupant in the bed or his absence by lack of such contact. The characteristic time of the pad material for returning to its original shape is substantially longer than the corresponding return time of the insulative layer. Reliable operation is obtained for a wide range of occupant weights regardless of the weight(s) of the previous occupants.Field of SearchWeight | |
