Abstract: A permanent magnet generator has a laminated rotor mounted to the driven shaft of a power alternator. The rotor is cylindrical and includes 10 circumferentially distributed elongated axial slots and 10 rotor teeth. Iron-boron-neodymium rare earth magnets are secured within each of the slots, radially and similarly polarized. The magnet and teeth define a consequent 20 pole rotor with a minimum number of magnets. The rare earth magnets are epoxy bonded within each of the corresponding slots. Each slot has a rectangular cross-section with slightly flared sides. The epoxy extends between the recess surfaces and the magnets. The flared sides improve the flux distribution. The outer radial ends of the magnets spaced inwardly of the rotor teeth prevent mechaical damage to the magnets. The outside maximum dimension of the PMG stator is slightly less than the inner diameter of the exciter stator for convenient removal through the bore of the exciter.

Abstract: A voltage regulator for a diesel engine driven alternator includes speed dip control permitting engine recovery, and a voltage signal circuit and a speed signal circuit producing a linear volts per hertz signal for controlling the RMS voltage of the alternator. A speed sensor is connected to the output of the permanent magnet generator. The signal is a filtered square wave with an accurate 50% mark-to-space ratio and converted to a pulse train coincident with the zero crossovers. A ramp circuit followed by a threshold detector and filter produces a linearly increasing voltage with decreasing speed. A level amplifier produces an output at a selected level. A rate amplifier responds to a derivative of the speed signal and clamps the level amplifier off at speed changes below a selected rate. A large and rapid speed change creates an output signal coupled to the reference side of an error amplifier to unload the alternator. The degree and rate of unloading is limited.

Abstract: A permanent magnet generator and rectifier is connected to the exciter of an alternator and a separate rectifier provides a D.C. voltage supply to a voltage regulator. A thyristor is connected in series with a second fuse across the exciter rectifier to short circuit the supply in series with a main external fuse. If the main fuse fails to open, the second fuse opens. The second fuse is potted in the regulators to prevent tampering. An overexcitation and a low voltage demand signal are sensed. The two signals are coupled to a NAND logic gate to produce an output shut-down signal. If either even is established and the first produces a signal, a shut-down signal is generated to a second comparator amplifier of latch circuit. A delay circuit connects the shut-down signal to a triggered oscillator for firing the thyristor.

Abstract: A universal motor connector unit is usable with different three phase and single phase motors for connecting the motors to different incoming voltages. The connector has a motor-mounted connector unit with 15 socket terminals and contacts in a fixed 3.times.5 matrix array. A complementing plug-in connector unit has pin contacts in a similar matrix and with U-shaped connections between the pin contacts. In a three phase connector, 12 pin contacts are in a 3.times.4 matrix. The plug-in unit in one orientation establishes a first winding connection for one voltage and when rotated 180.degree., a second voltage. The connector may also be used to change direction of rotation rather than voltage selection. For a single phase motor, the socket connector is the same as for the three phase motor. The plug-in unit is formed with separate plug-in elements; one is provided for voltage selection and a second for rotation selection.

Abstract: A fuse clip unit is constructed with an entrance unit having positive reject stops which prevent insertion of all except a selected fuse which provides branch circuit protection of 200,000 amps R.M.S. interrupting capacity. The selected fuse has a unique end nib which moves the stops to open the entrance unit and permit insertion of the fuse. The entrance unit may be integral with the fuse clip or formed as a separate cover. The fuse clip unit is secured within an insulating and mounting housing having clip chambers. A safety cover is secured to the housing overlying the chambers and includes a side insertion opening for each chamber which prevents access to the reject stops and thereby prevents manual moving of the stops to circumvent the reject stops.

Abstract: A centrifugal motor switch includes a base plate having a U-shaped fixed contact bracket and a leaf spring contact unit mounted to one side. The plate is mounted adjacent the field winding. The leaf spring is a flat rectangular spring plate including side deflection arms extending from a mounting strip and coupling arms connected to the deflection arms and to a central contact arm which extends outwardly. A wear pad is secured to the deflection arms and abutts the base plate to deflect the spring plate and locate the contacts. The contacts are secured to the fixed support and contact arm. A tab projects from the contact arm to the pad to minimize contact vibration. The bracket is formed of magnetically conductive metal and has side walls partially enclose the contact. A centrifugal operator on the shaft engages the pad and causes axial movement of the pad and spring plate with a rocking motion to rock the contacts.

Abstract: A bearing locking construction for dynamoelectric machines having a bearing locking assembly which can be located in place after an electric motor or other dynamoelectric machine is completely assembled. The construction includes a bearing housing which has at least a pair of abutments located on opposite sides of the motor shaft which house a fastening means for locating the bearing lock and securing the bearing in its seat and consists of fasteners which are assembled through the abutments from the outboard side of the motor and has a large T-shaped head rotated by rotation of the fastener to overlap the bearing on one side and an axially spaced seat on the opposite side.

Abstract: A centrifugal actuator for activating a stationary switch in a single phase induction motor which has a hub with a central opening inside a central body portion for assembly and securement on the shaft of a motor for rotation thereby. The hub has a flat outer member for contacting the switch to actuate starting windings of the motor when the motor is in a rest condition and is removed from the switch under centrifugal action by weights located inside the actuator to cut out the starting windings when the motor is in a run condition.

Abstract: The strain relief grommet has internally located intermittent clamping teeth and when the grommet is located around a cord set and then lodged in a notch in a frame of a motor, teeth pierce the outer jacket of the cord and engage the internal insulation wrappings around the lead wires. This prevents removal or loosening of the cord from its internal connection in the event the cord set is pulled from outside of the motor.

Abstract: A brushless exciter rotor mounting of a sleeveless design directed to a rotor core which is mounted on the shaft of an AC generator so that the rotor core can be rotated by the generator to provide direct current to the generator. The shaft has a stepped construction providing a larger diameter of the shaft at the inner end portion and a lesser diameter portion of the shaft extending outwardly therefrom. The rotor core has a slightly larger inner diameter than the lesser diameter portion of the shaft for a predetermined length to provide a radial clearance therebetween. At the inner end of the shaft the rotor core pilots to the larger diameter end portion of the shaft and at the outer end portion of the shaft a standoff casting pilots to the shaft. The shaft is keyed to the rotor core to prevent rotation of the shaft within the rotor core.

Abstract: A fuseholder with a reject spring which will only accept a ferrule type fuse with an annular groove in the ferrule at one end. The reject member is a reinforcing spring located externally of the fuse clip on the fuseholder and has locking or control members integrally connected to abutments extending through complimentary openings in the sides of the fuse clip. The arms of the spring are connected together in a manner to control lateral movement of the fuse clip within a predetermined distance and also controls lateral movement of the abutments to respectively accept only the groove of a ferrule type fuse when moved outwardly. The reinforcing spring with the reject abutments finds use on fuseholders having no or very low barriers.