Abstract: A method for making a core for one of a rotor and a stator for use in an electric motor, the core being formed from a plurality of laminations, includes forming a predetermined number of through-material slots in a first portion of a material stock, forming at least one angled interlocking projection in the material stock, the projection having a circumferential length and being formed so that at least a portion of the projection remains integral with the material stock, cutting the material stock to define a receiving opening corresponding to the interlocking projection, the receiving opening positioned relative to the projection at an angle &phgr; that is a whole number multiple of &bgr;, where &bgr; is an angle defined as a ratio of 360 degrees to the number of slots and cutting the material stock to form a first substantially circular lamination. Second and third laminations are formed in kind.

Abstract: A method and apparatus for detecting the presence of a ground leakage path in an electric motor system including an alternating current (ac) electric motor coupled for receiving electric power from a switching inverter of the type having, for each phase of the motor, a pair of serially connected electronic switching devices connected between relatively positive and negative direct current (dc) voltage buses with the switching devices being alternately gated into and out of conduction for providing switched electric power to the motor. The inverter includes a current detector for detecting current in the relatively negative voltage bus. The method comprises initially applying a gating pulse each time the motor is energized to the switching device of each phase connected to the negative voltage bus and identifying a ground leakage path when such gating pulse produces current at the current detector.

Abstract: A power control system in combination with a three-phase AC motor coupled to a water pump enables the operation of the motor at speeds up to 10,800 RPM so as to provide improved pumping capacity with a smaller motor and smaller pump. The control system supplies AC power to the motor with a frequency of the power being increased at a first high rate up to a frequency at which pump pressure is about equal to a value at which water is being pumped from the outlet pipe of the pump. Thereafter, AC power frequency is increased to the second, slower rate up to a maximum operating frequency of the motor. During the time that frequency of the AC power is being increased, motor current is continuously monitored and compared to a maximum allowable current. If monitored current exceeds allowable current, the frequency of operation is decreased until monitored current is less than the allowable current. Thereafter, frequency is again increased so long as monitored current is less than allowable current.

Abstract: A permanent magnet rotor includes a core and a plurality of magnetizable elements adhesively secured to the outer surface of the core. The core and adhered magnetizable elements are cold-pressed into a deep drawn cup-shaped outer metallic shell having a substantially closed end wall and an opposite open end defined by a peripheral edge which is rolled over the periphery of an end plate to encapsulate the core and magnetizable elements within the shell with an insulator disk disposed between each end of the core and the adjacent shell end wall and end plate. The permanent magnet rotor may be formed by a method and apparatus that cold press the core and magnetizable elements into the cup-shaped shell and form the peripheral edge of the shell over the end plate to effect encapsulation.

Abstract: A dynamoelectric machine having a stator housing or frame made by a lost foam process utilizing a unitary single-piece vaporizable pattern. The stator housing may be made from a molten metal such as cast iron or aluminum, and has an annular wall having integral outwardly extending longitudinal cooling fins, mounting foots pads and a conduit box support pad. The lost foam process enables the cooling fins to have a greater effective cooling fin height to housing diameter ratio and greater effective cooling fin height to housing annular wall thickness ratio than obtained with prior sand casting processes. The greater height fins provide increased strength and rigidity for the annular wall which can be made radially thinner than prior stator housing or frames of similar size. Substantial savings in material and labor are realized by the stator housing.

Abstract: A dynamoelectric machine constructed for speed and accuracy of manufacturing has a stator core constructed of 90.degree. symmetrical stator laminations and the windings have differing numbers of poles which overlap in slots of the stator core are wound of the core formed by the laminations in unique fashion. The rotor bars of the machine are skewed to optimize performance of the machine when in the form of a single phase induction motor. Magnet wire leads of the windings are connected directly to terminals on a plug and terminal assembly which is formed for positive location on an end frame of the machine without welding or other fastening to the end frame. The end frames of the machine and stator laminations forming the stator core are formed so as to increase the precision of the final position of the stator relative to the rotor assembly of the dynamoelectric machine. The end frames are constructed for grounding without the use of fasteners or wire.

Abstract: A motor having a power switching circuit adapted to be connected between a power source and its winding for selectively energizing the winding to generate a magnetic field which causes a rotating assembly to rotate. A position sensing circuit provides a position signal representative of the position of the rotating assembly and a commutating circuit controls the power switching circuit to commutate the power switching circuit at a commutating angle to achieve a desired rotating speed of the rotating assembly. The commutating circuit varies the commutating angle in response to the position signal to maintain the substantially constant rotating speed of the rotating assembly. As result, the efficiency of the motor is varied to maintain the substantially constant rotating speed.

Abstract: A rotor end cap for use with a rotor of a dynamoelectric machine to induce cooling air circulation, facilitate rotor balancing and enable rotor rotational position and speed sensing. The rotor end cap includes a base for attachment to a rotor of the dynamoelectric machine so that the base turns with the rotor. Further, the end cap includes a plurality of blades extending from the base in axial and radial directions with respect to the rotor for moving air to enhance cooling air circulation within the machine as the rotor turns. Still further, the end cap includes a balancing device extending from the base for altering a weight distribution around the base to balance the rotor. Yet still further, the end cap includes at least one shutter extending partially around the base for intermittently blocking passage of light as the rotor turns to enable rotational position and speed sensing of the rotor.

Abstract: A motor has a stationary assembly including three windings in magnetic coupling relation to a rotatable assembly, the position of which is sensed by a position sensor. A converter, adapted to be coupled to a power supply, energizes each of the windings with a voltage. The converter is responsive to the angular position and speed of the rotatable assembly for selectively energizing each of the windings according to a preselected sequence. The converter energizes each winding with the voltage throughout a commutation period when a back EMF induced in such winding has a polarity opposite to a polarity of the voltage energizing such winding, the commutation period for each winding overlapping the commutation period for another winding. Alternatively, the converter energizes each winding with the voltage throughout a commutation period of 180 electrical degrees, the commutation period for each winding overlapping the commutation period for another winding.

Abstract: A hollow actuating ring and apparatus for actuating and/or vectoring the flaps of an aircraft gas turbine engine nozzle by transferring actuation loads from a small number of actuators to a greater number of pivotal divergent flap members of the nozzle. The actuating ring has a generally hollow annular structure including axially spaced apart coaxial forward and aft walls, struts axially extending between and structurally joining together the forward and aft walls, and a ring stiffening for decreasing the effective ring bending and torsional length of at least one of the forward and aft walls between the struts. Stiffening structure is provided for spreading out loads transferred from the struts to one of the forward and aft walls using structural braces extending diagonally between the struts and one of the forward and aft walls.

Abstract: A variable stator vane assembly which substantially eliminates leakage paths by utilizing a cantilevered finger spring seal and an o-ring is described. In one form, the stator vane assembly includes a spacer configured to form, with an upper, or outer, surface of the vane trunnion bushing, an annulus. The ring shaped cantilevered finger spring seal is positioned in the annulus and forms a seal between the spacer and trunnion bushing. The stator vane assembly also includes, in one form, an o-ring located at an interface between the stator case and the stator vane metal jacket.

Abstract: An apparatus for injecting a plurality of coil groups into a stator core of a dynamoelectric machine is described. The injection apparatus includes, in one embodiment, a stripper assembly including a first stripper. The first stripper includes an injection disk which, in one embodiment, is formed from nylon. A first surface of the injection disk is configured to contact a segment of at least one of the coils to move the coil axially along the blades of the injection apparatus without contacting portions of the coil in gaps between the blades.

Abstract: Methods of manufacturing an apparatus adapted to be connected to a power source, the apparatus for driving a rotatable component. A motor has a stationary assembly and a rotatable assembly in magnetic coupling relation to the stationary assembly, the rotatable assembly in driving relation to the rotatable component, the stationary assembly including windings adapted to be energized by the power source to produce an electromagnetic field for rotating the rotatable assembly, the windings having a maximum desired operating temperature and a predetermined minimum desired temperature rise. A heater is in heat exchange relationship to an outer surface of the windings, the heater adapted to be connected to the power source at least when the motor windings are not energized to generate heat transferred to the windings to increase the temperature of the windings. An optional thermostat may be connected in series between the heater and the power source.

Abstract: An air fuel mixer is disclosed having a mixing duct, a shroud surrounding the upstream end of the mixing duct in which a fuel manifold is provided in flow communication with a fuel supply and control means, a set of inner and outer counter-rotating swirlers adjacent the upstream end of the mixing duct for imparting swirl to an air stream, a hub separating the inner and outer annular swirlers to allow independent rotation of the air stream, and a centerbody located axially along and substantially the full length of the mixing duct. In order to inject one type of fuel into the mixing duct, fuel is supplied to the outer annular swirlers which include hollow vanes with internal cavities, wherein the internal cavities of the outer swirler vanes are in fluid communication with the fuel manifold in the shroud. The outer swirler vanes further include a plurality of fuel passages therethrough in flow communication with the internal cavities.

Abstract: A permanent magnet rotor for an electronically commutated motor (ECM) has a core, a plurality of magnetizable elements spaced around the core, and a thin-walled retaining shell which has been stretched around the core and magnetizable elements to hold the elements in position. The rotor is made by an inventive method which involves axially aligning the core and surrounding magnetizable elements with the retaining shell, and cold-pressing the retaining shell over the core and elements to sandwich the elements between the shell and core. The core and magnetizable elements serve as a mandrel about which the shell is reformed in a cold working operation. Other aspects of the invention include the fixturing apparatus used to align the core and magnetizable elements with the retaining shell, and apparatus which is used to evenly space the magnetizable elements around the core and hold the elements in position during at least a portion of the cold-pressing operation.

Abstract: A simple cycle gas turbine engine which includes a variable flow booster, a small high pressure compressor, and a power turbine is described. The variable flow booster, which includes a low pressure compressor, has at least two flow paths. In one embodiment, variable bleed valves, or doors, are used to control air flow through respective booster flow paths. In one embodiment, a first flow path directs air flow around booster compressor to the core engine, and a second flow path directs air flow at least partially through the booster compressor.

Abstract: A gas turbine engine operable so that, in one embodiment, by adjusting the speed of an intercooler fan, the orientation of a variable inlet guide vane, and the orientation of a variable area turbine nozzle, the conditions at the inlet of the high pressure compressor are substantially the same for an ambient air temperature within the range of 59.degree. F. and 100.degree. F. The engine, in one embodiment, includes a low pressure compressor, a high pressure compressor, and an intercooler, including a fan, for cooling air output by the low pressure compressor and supplying the cooled air to the high pressure compressor.

Abstract: A seal assembly positioned between forward and aft rotor stages of a turbine separates a forward cavity and an aft cavity on each side thereof. The seal assembly includes a seal body connected to a platform portion of a stator nozzle located between the forward and aft rotor stages, wherein an inner seal cavity in flow communication with an insert in the stator nozzle is formed therebetween. A static seal member is arranged in sealing relationship with a rotary toothed member between the forward and aft cavities, with the static seal member being connected to the seal body. An intermediate member is positioned between the seal body and the static seal member to define a plenum therebetween in flow communication with the inner seal cavity, the intermediate member having a plurality of angled passages formed therein in which a first end thereof is in flow communication with the plenum and a second end thereof is in flow communication with the aft cavity.

Abstract: A rotor blade for a rotor of a gas turbine engine having an axis of rotation including a root portion, a platform portion connected to the root portion and having a damper pocket formed therein, an airfoil portion connected to the platform portion, a generally bar-shaped damping member loosely arranged in the damper pocket having at least one scrubbing surface, and at least one retainer pin for retaining the bar-shaped damping member in the damper pocket. The bar-shaped damping member is slidably displaceable and rotatable within the damper pocket during rotation of the rotor. The damper pocket in the platform portion has a rear surface with an upper portion and a lower portion at an angle to the upper portion, a pair of spaced side surfaces, and a pair of spaced lower surfaces extending from the rear surface lower portion which are substantially coplanar.

Abstract: A method and apparatus for preventing overspeed of an electrically powered .[.golf car.]. .Iadd.vehicle .Iaddend.having a shunt wound direct current electric motor with an armature winding and a field winding serially connected to respective switching devices and to a source of on-board direct current electric power. The .[.golf car.]. .Iadd.vehicle .Iaddend.includes a control adapted and connected to regulate the current in each of the armature and field windings for controlling speed in response to an operator's command. The .[.golf car.]. .Iadd.vehicle .Iaddend.incorporates overspeed detect sensing the magnitude of current in each of the armature winding and the field winding and detecting when the current in the armature winding reverses direction. The magnitude of the armature winding current upon such reversal is compared to a preselected value and an overspeed signal generated when the reverse current magnitude exceeds the preselected value.