Abstract: A relay coil is fixed in a housing adjacent a pair of vertically spaced, stationary contacts, which are electrically insulated from one another, and which have associated terminals that project exteriorly of the housing. A pair of resilient switch arms project from a stationary metal plate in the housing transversely across one end of the armature coil in spaced, parallel relation to each other. At their ends remote from the metal plate the switch arms carry a pair of contacts which register with the stationary contacts in the housing. An armature member is secured to and extends along the inside surface of each switch arm in confronting relation to the adjacent end of the armature coil.

Abstract: The device includes a thermostat which is potted or secured by epoxy in a recess in the closed end of a generally cup-shaped, dielectric housing. A generally disc-shaped, aluminum alloy casting is secured coaxially against an opening formed in the bottom of the housing, and against a PTC resistor which is positioned in the opening between the casting and the thermostat, and in electrical contact with the latter. A bimetallic coil is mounted in the open end of the housing with its inner end staked to an integral post on the Al casting, and with its free end mounted to unwind or rotate angularly in the housing with changes in ambient temperature. The Al casting functions as a heat sink which can be trimmed, before being secured in the housing, to calibrate the bimetel coil.

Abstract: The switch includes a generally J-shaped, bimetallic switch arm having two, spaced, parallel legs, one of which is longer than the other. The shorter leg is welded at its outer end to a metal boss, which is formed on the face of a mounting bracket, and thus supports the longer leg above the face of the bracket so that a first contact on the outer end of the longer leg overlies, and is normally engaged with, a second contact, which is mounted on said bracket to be insulated therefrom. The high expansion side of the switch arm faces downwardly to confront the bracket, and since the shorter leg responds more rapidly to temperature changes than the longer leg, it tends to resist movement of the longer leg between open and closed positions and thereby prolongs the time the switch arm remains in either position.