Piezoresistive elevator button

摘要

A piezoresistive elevator button assembly comprises a polymer film piezoresistive element sandwiched between a button and a button pressure plate, and circuitry for sensing a change in the resistance of the piezoresistive element. The piezoresistive element is held in place by a high temperature potting compound to create a button less sensitive to fire or heat. A compensating spring is placed between the piezoresistive element and the buttom pressure plate to eliminate the effect on that element due to temperature cycling of the button assembly elements. A frustoconical housing of the button employing catch teeth allows for little movement; the use of the polymer film piezoresistive element allows a signal to be generated though buttom movement is nearly imperceptible.