Abstract: An electronic safety circuit for a portable gas heater includes a transformer and half wave rectifier connected in parallel with a fan motor for charging a capacitor, and a solid state switching circuit, which may be either a pair of cascaded transistors, an SCR, or a Darlington switch, for applying a reverse polarity voltage across the solenoid of a solenoid operated gas valve to immediately turn off the gas valve in the event of loss of power to the combustion fan motor. The electronic safety circuit may be conveniently mounted on a PC board and enclosed in the combustion fan motor.

Abstract: A shading band for use in creating a shading pole in a shaded pole motor has tapered edges along its length, instead of the square cross-sectional edges with 90.degree. inside angles of the prior art, in order to increase the thickness of epoxy deposited thereon which insulates the winding slot within which the shading band extends. The shading band may be formed with a cross-sectional shape of many different geometries, as long as its cross-sectional shape does not include inside angles less than 90.degree.. The edge height for each shading band should be controlled in order to maintain an effective angle of transition from the wire slot sidewall tot he shading band of greater than about 90.degree..

Abstract: A generally annular heat sink is adapted to be compressed and inserted within the cylindrical sleeve of a motor or the like, with the spring action of the heat sink being sufficient to hold it in place after it is released. Channels along the outer surface of the heat sink provide reservoirs for a potting compound to further fix the heat sink and improve the thermal conductivity between the heat sink and sleeve. A PC board is mounted to the heat sink only through the electrical leads of power transistors to provide a limited amount of flexure to accommodate insertion and removal of the heat sink. In a second embodiment, a generally rectangular heat sink is mounted in a conduit box by tabs which are deformed to fit within channels along opposite edges of the heat sink. An access hole in the side of the conduit box and aligned with the channel permits a pin to be inserted therethrough to push the tabs out of the channel and release the heat sink and PC board from the conduit box.

Abstract: A self-aligning bearing and end shield mount for an electric motor or the like. The bearing mount has a spacer with a hub through which the rotor shaft extends and fingers that seat within an annular locating groove of the rotor shaft for securing the spacer to the shaft. The spacer also has a thrust surface. A spring has a hub portion through which the rotor shaft extends and a ring surrounding the hub with resilient arms therebetween. The spring also has a bearing seat and a thrust plate seat. A self-aligning bearing is seated in a bearing socket in the end shield of the motor housing and in the bearing seat of the spring. A thrust plate is seated within the thrust plate seat of the spring with the thrust surface of the spacer running against a surface portion of the thrust plate.The oil cap mount inlcudes circumferentially spaced protrusions extending out of the surface of the end shield and formed integrally therewith to define an oil cap seat.

Abstract: A multi-piece rotor for a dynamoelectric machine includes a core which is bore mounted to a shaft, and one or more annular sleeves which are slip fit and glued onto the shaft, the annular sleeves being characterized by a plurality of longitudinally extending ridges formed along the inner surface thereof, with one or more grooves cut in the inner surface between adjacent ridges such that as the sleeve is assembled to the core, the ridges contact the core and, if tightly fit to the core, the grooves provide adequate space for the insertion of adhesive.

Abstract: A self-aligning bearing and end shield mount for an electric motor or the like. The bearing mount has a spacer with a hub through which the rotor shaft extends and fingers that seat within an annular locating groove of the rotor shaft for securing the spacer to the shaft. The spacer also has a thrust surface. A spring has a hub portion through which the rotor shaft extends and a ring surrounding the hub with resilient arms therebetween. The spring also has a bearing seat and a thrust plate seat. A self-aligning bearing is seated in a bearing socket in the end shield of the motor housing and in the bearing seat of the spring. A thrust plate is seated within the thrust plate seat of the spring with the thrust surface of the spacer running against a surface portion of the thrust plate.

Abstract: A generally rectangular heat sink is mounted in a conduit box by tabs which are deformed to fit within channels along opposite edges of the heat sink. An access hole in the side of the conduit box and aligned with the channel permits a pin to be inserted therethrough to push the tabs out of the channel and release the heat sink and PC board from the conduit box.

Abstract: An end shield for an electric motor or the like includes a generally disk shaped planar portion having a cylindrical bearing socket therein for mounting a cylindrical bearing. The socket has a cylindrical side wall and an end wall, and is formed from ears and tabs from the material of the disk such that the ears are bent out of the plane of the disk to extend at right angles to the planar portion. The ears define the cylindrical side wall of the socket. The tabs extend generally radially inwardly and define the end wall of the socket. A cylindrical bearing within the socket is retained radially and in axial alignment by the cylindrical side wall of the socket, and is restrained in an axial direction by the end wall of the socket. A spring may be mounted within the socket to resiliently preload the bearings of the motor in the axial direction.

Abstract: A housing for an electric motor includes a cylindrical sleeve and an end shield in the form of a circular disk that fits within the sleeve. The sleeve has tabs that extend inwardly and define stops to locate the end shield in one axial direction and position it perpendicular to the longitudinal axis of the sleeve. The end shield has circumferentially spaced recesses at the outer edge and in the outer surface thereof. The sleeve has protrusions that extend into the end shield recesses with the end shield positioned against the stops. The protrusions and recesses cooperate to locate the end shield in the other axial direction and secure it against rotational movement relative to the sleeve, whereby the end shield is firmly secured perpendicular to the longitudinal axis of the sleeve against both axial and rotational movement.