A miniature device for sensing overheating of bearings has a small flat-bottomed circular cup (e.g. fifteen millimeters in diameter) and has an integrally connected co-axial heat-conducting rod extending downwardly from its lower surface for good heat-exchange insertion into a bore made for it in a bearing element. The rod is preferably threaded to improve both its anchorability and its heat-exchange value. A bimetallic snap-disc thermostat lies in and on the bottom of the cup. A small inverted cup of electrically insulating hard plastic has a beaded lip embraced by the crimped rim of the metallic cup to form a housing for a normally closed switch whose spring-arm contact elements are fixed to the inverted plastic cup. An insulating disc closes the bottom of the inverted cup, forms a shallow retaining chamber for the snap-disc, and is centrally axially bored to serve as a guide for an insulating pin by which the thermostat disc operates the switch. The switch assemblage is packed in insulating plastic material in a close-fitting plastic housing.
A thermostat device comprises a thermostat unit having a surface which faces in a first direction and which is preferably disposed in thermally-coupled heat-transfer relation to an object whose temperature is to be monitored so that the thermostat unit is promptly responsive to an object temperature, the unit also having other surfaces which face in an opposite direction. A metal mounting bracket plate has a base portion, has a stud secured to the base portion to extend in one direction from the base for securing the plate to the object to be monitored in thermally-coupled heat-transfer relation to the object, and has integral spring portions upstanding from respective opposite ends of the base portion of the plate. The spring portions have openings fitted over respective portions of the thermostat unit so that parts of the spring portions around the margins of the openings engage said other unit surfaces for detachably attaching the bracket plate to the unit and for resiliently biasing the first unit surface against the base portion of the bracket plate to be thermally-coupled in heat-transfer relation to the object to be monitored.
In a snap disc thermostat, a stationary contact support, a moveable contact support, an actuator translated by the disc and a case housing those elements, interior side walls of the case have guide channels outboard of the stationary and moveable contact supports. The actuator has a part substantially circular in section, extending within the guide channels, and a spherical part abutting the moveable contact support. The case has a closed top through which two contact terminals extend, and an open bottom through which the housed elements can be mounted. The open bottom is closed by an imperforate disc. The case has projections integral with the case, extending beyond the rest of the open bottom to center and retain the disc. A disc closure has recessed seats deeper than the projections, receiving the projections without bottoming, a flat surface within the compass of the seats, engaging the disc, and surfaces defining a plane outboard of the seats against which the disc closure abuts. An elongated mounting stud has a shaft, non circular in transverse cross section, with interrupted threads along it, and a non-circular shank projecting into an opening in the disc seating plate, and staked. The stationary contact arm projects from a wall of the case at an acute angle in a direction toward the disc. L shaped terminals can be mounted to provide three predetermined spacings between tabs perpendicular to the feet.
A thermostat device comprises a thermostat unit having a surface which faces in a first direction and which is preferably disposed in thermally-coupled heat-transfer relation to an object whose temperature is to be monitored so that the thermostat unit is promptly responsive to changes in object temperature, the thermostat unit also having other surfaces which face in an opposite direction. A metal bracket mounting means comprises a plate having an integral base portion extending in a plane to be secured to an object to be monitored, having an opening in the base portion of the plate, and having a pair of integral spring portions of the plate upstanding from said plane at respective opposite sides of the opening, the spring portions having distal ends thereof folded toward each other and back toward said plane to engage the second surface portions of the thermostat unit for detachably attaching the bracket means to the thermostat unit and for resiliently biasing the unit toward the object to be monitored so that said first surface of the unit extends through the base opening into thermally-coupled heat-transfer relation to the object.
A thermal switch apparatus having an adapter mount that snaps to a modular thermal switch by hand or with the use of a simple tool. The thermal switch apparatus of the invention is embodied as a thermal switch apparatus including an adapter having a mounting apparatus and a receptacle, the receptacle having a female portion structured internally with a retainer. A modular thermal sensing device includes a male portion sized to enter the female portion of the receptacle, the male portion having an external relief structured to interlock with the internal retainer of the female portion. The male portion of the modular thermal sensing device is installed into the female portion of the receptacle, the retainer of the receptacle being mated with the external relief of the modular thermal sensing device.
