Abstract: A plastic coil bobbin has a recess with the precise dimensions of a thermal fuse. On one side, the recess is open so that, as the coil is wound on the bobbin, successive layers of coil wire form a wall-like surface closing that open side. As the fuse is press fit into the recess, it is also forced into intimate contact against the wall of wire. Thus, the only material between the fuse and wire is a thin plastic shell forming the fuse housing. Since the fuse rating takes this wall thickness into account, there is effectively no thermal insulation between the coils and the fuse. Accordingly, under overheating conditions, the fuse opens a circuit when there is overheating and before a fire can start.

Abstract: Apparatus for mounting a thermal overload protector to the compressor motor of a hermetically sealed compressor unit. The apparatus includes an arcuate bracket which follows the radial curvature of the stator laminations and which is mounted to the stator end face by bolts simultaneously used to secure the laminations in place. A hollow protector holder made of insulating material is received by a sliding snap-fit on an upstanding plateau in the bracket and is held against rotation therein, the inside of the holder being specifically contoured to receive and hold an overload protector of preselected shell geometry.

Abstract: A mounting bracket for a heat detector switch which not only provides a convenient means for mounting the switch on a bearing or motor but which also prevents the heat detector switch from being damaged while thereon. The bracket comprises a flat plate having a hollow tubular member mounted on the top surface of the plate member at one end thereof. A heat detector switch is mounted on the top surface of the plate adjacent the other end thereof and is electrically connected to an electrical wire which extends through the tubular member. A protective shield extends over the heat detector switch. The interior of the tubular member and the protective member are filled with a silicone rubber material. The heat detector switch is activated upon the motor or bearing reaching a predetermined temperature to activate a signal device electrically connected to the electrical wire in the tubular member.

Abstract: A combination starter-protector device for a winding circuit of a dynamoelectric machine. The device has a housing with at least one terminal therein adapted for connection with a power source, and means is provided in the housing for controlling starting of the dynamoelectric machine. Means is mounted to the housing for electrical contact and positioning engagement with the starting controlling means and adapted for connection in circuit relation with the winding circuit. Another circuit is provided between the engagement means and the at least one terminal for supplying power to the winding circuit when the engagement means is connected in circuit relation therewith, and the other circuit includes means in the housing and operable generally in response to a certain thermal condition occasioned upon winding circuit overload for interrupting the other circuit.Other combination starter-protector devices are also disclosed.

Abstract: A rotary transformer having a stator and a rotor is energized by a power supply at commercial power frequency; sensors are located on the rotary part of the machine and provide sensing output signals, at discrete threshold levels, to a threshold circuit which, in accordance with the sensed signals, provides loading on the transformer secondary in discrete steps; the loading on the secondary is reflected into the primary and sensed to provide, selectively, alarm or stop-motion signals if operating parameters, typically temperature, as sensed by the sensors, reach levels necessitating an alarm or even a stop-motion signal.

Abstract: A method of assembling a temperature responsive resistance member within a pair of separable housings. This method includes the steps of: mounting the temperature responsive resistance member in both supporting engagement and electrical contacting engagement between a pair of electrical terminals; and joining the separable housings against displacement so that the temperature responsive resistance member in both the supporting engagement and the electrical contacting engagement with the terminals is disposed within the housings in predetermined spaced relation therewith with portions of the terminals extending exteriorly of the housings.

Abstract: A molded thermstat strap is provided having a central thermostat receiving well. The strap is intended for insertion between the windings of a dynamoelectric machine, for example, an electric motor, during manufacture of the motor so that a thermostat element can be positioned between the windings after motor construction is completed. The strap includes a central well having wing members extending outwardly from opposite sides of the well. Means for removably locking a thermostat within the well is formed integrally with the strap. Means also is provided for holding the strap positionally secured in relation to the motor windings so that the strap does not move during motor constructional steps accomplished after placement of the strap between the motor windings.

Abstract: To provide for even running and uniform torque output of pulse-energized motors, elements having soft-iron characteristics are located outside of the air gap, but within the stray, or leakage field emanating from the poles of a permanent magnet rotor, the elements being shaped and located with respect to the windings to exert a braking torque on the rotor when the rotor is in a position with respect to the coils of the motor for efficient energization of the coils, the magnet elements interacting with the field from the rotor during the gaps of energization to release the stored energy therein. The magnet elements may be yoke elements located adjacent, or outside of the air gap, soft-iron sheet metal strips, adjustably positioned on the stator, or the like.

Abstract: A pump for circulating cooling and lubricating liquid is driven by a motor which comprises a central rotor; a tubular housing coaxially surrounding the rotor and normally filled by the cooling and lubricating liquid; and a stator coaxially surrounding this tubular housing. Heating elements are provided between the coil ends of the stator and the tubular housing for heating the liquid in this housing, during or after a shutdown of the motor, when the liquid is likely to have congealed or at least to have become viscous.

Abstract: Gyroscope motor of the type comprising a magnetized rotor constituted by a permanent magnet in the shape of a toroid, within which are disposed the stator windings, the commutation being ensured by means of a static detector operating by variation of the impedance of a winding placed in the magnetic circuit, wherein the saturation of said magnetic circuit is obtained directly by means of the field of the rotor.

Abstract: A coil bobbin for a sub-fractional horsepower motor is formed with a cavity in one flange opening outward from the flange rim, a partition dividing the cavity into two chambers. One chamber has a cross-sectional shape adapted to receive a thermal sensing device and the other has a cross-sectional shape adapted to receive an insulated terminal wire. The thermal device has a metal body as one terminal of the device and a projecting rectangular metal portion as the other terminal. One start wire of the coil is wound around or otherwise secured to the projecting terminal and the thermal device is inserted into one chamber from the open end. The partition is partially slotted and the stripped end of the lead wire is inserted in the other chamber from the other end, the stripped and bent-over end of the lead wire extending through the slot. As the thermal device is pushed into its chamber its metal body forces the stripped end against the partition and into electrical connection with the stripped end.