Method of making a stem seat for a piston and cylinder type thermal device

摘要

A piston and cylinder type thermal device having a resilient stem seat provided with an opening in one end thereof and receiving an actuating stem in the opening that is adapted to reciprocate in the opening in response to the thermal expansion and contraction of a charge of material in the device and operatively acting on the stem seat adjacent the other end thereof. The opening includes one portion thereof adjacent the other end of the stem seat that is substantially smaller in diameter than the diameter of the portion of the stem that is to be received that one portion when the stem seat is in the unassembled condition thereof. The opening further includes another portion thereof adjacent the one end of the stem seat that is substantially smaller in diameter than the diameter of the portion of the stem that is to be received in said other portion when the stem seat is in the unassembled condition thereof. The opening further includes an intermediate portion of the opening that joins with the one portion and the other portion thereof and has a diameter that is substantially the same as the diameter of the portion of the stem that is to be received in the intermediate portion when the stem seat is in the unassembled condition thereof.