Emerson Electric Company

Jerry D Lloyd

Alan D Crapo

Mohamed A Hilal

Yue Li

Renyan W Fei

Benjamin Bowsky

Bernard T Brown

Pradeep K Sood

M A Hilal

An improved rotor for an induction motor is disclosed. In one aspect of the disclosed invention, endshield laminations are placed on the top and bottom of a lamination stack of a rotor. The endshields have holes therein which mask the ends of the bar members within the lamination stack. The unmasked portions of the bar members are connected through the holes to connection members in such a fashion to make multiple compound short-circuit loops. Because the endshields, like the laminations generally, are not conductive, the connection members are only in contact with the bar members through the holes in the endshield, which prevents the multiple loops from shorting to one another. The bar members and connector members are preferably die-cast in and around the rotor laminations and the endshields.

Diecast rotor with compound short-circuit loops and method of manufacture

A rotor for a two-pole synchronous reluctance or a switched reluctance motor can be constructed from a stack of flat, planar laminations of grain-oriented materials. To enhance the necessary anisotropy of reluctance, slots are provided in the lamination along the magnetic flux lines in the preferred grain direction. The laminations may be provided with an essentially circular outer perimeter, and slots for a squirrel cage winding provided. A complete, efficient squirrel cage winding can thus be provided for a two-pole synchronous reluctance motor for starting purposes.

Line-start reluctance motor with grain-oriented rotor laminations

A reluctance machine system including a reluctance machine having a stator including at least one phase winding and a rotor defining rotor poles and inter-pole gaps, where permanent magnet inserts are positioned within the inter-pole gaps to interact with the currents in the phase windings to provide permanent magnet torque and to improve the machine's performance.

Reluctance machine with permanent magnet rotor excitations

An axial flux reluctance machine including a rotor formed from a wound tape of paramagnetic material, a first stator formed from a wound tape of paramagnetic material and a similarly constructed second stator, where the first and the second stators define stator poles and wherein the stator poles of the first stator are not completely aligned with the stator poles of the second stator. Also a reluctance machine system for energizing the axial flux reluctance machine and methods for forming the wound tape rotor and stators.

Axial flux reluctance machine with two stators driving a rotor

This invention provides a method and apparatus for balancing a system including a salient pole rotor machine and an off-balance load. The illustrative embodiment of this invention provides a method and apparatus for balancing the system by positioning a balancing compound between the poles of the rotor of the machine.

Method and apparatus for balancing a load with a salient pole rotor

A field installable device for a conventional heating and air conditioning system (HVAC) is provided which operates a blower fan in conjunction with a standard thermostat. Presently, HVAC systems operate in four modes: heating, cooling, off and fan 'on'. The device includes a multi-pole, multi-speed motor and a control operatively connected between the thermostat and the motor. With the fan switch in the 'on' position and heating or cooling called for, the control causes the blower to operate at a high speed, which may be different for heating or cooling. When the pre-selected temperature is reached the particular thermal operation (i.e., heating or cooling) is stopped. The control switches the motor to a speed substantially slower than the operating condition speed to provide continuing air circulation until the thermostat again calls for thermal operation. With the switch in 'auto' position, the blower operates similarly to present systems.

HVAC low power usage circulation blower

A motor (10) comprises a stator (14) having an associated stator winding (24) formed of a conventional material such as copper, or of a superconductive material. A rotor (12) for the motor is also formed of a superconductive material. The rotor is placed in a cryostat (16) and cooled from a first temperature which is above a critical level to a second temperature which is below the level. The stator is placed in a second and separate cryostat (18) and the stator winding is energized while the rotor temperature is being lowered to below the critical level. Once the superconductive material of the rotor has been cooled to a level below the critical level, the stator winding is de-energized. Currents are now induced in the superconductive material of the rotor to trap or maintain magnetic flux therein. Thereafter, the rotor acts as a permanent magnet so long as it is maintained below the critical temperature.

Flux trapped superconductor motor and method therefor

A brushless homopolar dynamoelectric machine motor (1) has a rotor (3) with a least one winding (5) having multiple turns. The rotor is inductively charged using a flux pump or a rectifier. Solenoid pairs (15a, 15b, 17a, 17b) comprise field windings for the motor and compensate for winding and field losses. The motor is an axisymmetric motor in which superconductive materials are used.

Superconducting brushless homopolar motor with multiple winding rotor

A superconductor motor (10) comprises a stator assembly (14) which includes a plurality of solenoids (40-44). A rotor assembly (12) includes a disk (20) of superconductive material in which are entrapped magnetic lines of flux which cause the rotor to function as a magnet. The lines of flux tend to creep throughout the disk over time thereby reducing the magnetic properties of the rotor assembly and decreasing motor performance. A plurality of coils (48a-48l) are carried by the disk. The stator solenoids are energized to produce rotation of the rotor, and the coils are energized in a predetermined manner to compensate for the flux creep in the disk and to restore the rotor assembly's magnetic properties thus to prevent deterioration in motor performance.

Flux trapped superconductor sychronous motor with creep compensation

A superconducting motor (1) comprises a stator (3) and a rotor (5), both of which employ superconductive windings. The rotor includes two sets of windings, a large rotor winding (13) and a small rotor winding (15). The windings are connected to form a current loop (16) which is exposed to a magnetic field. Switches (S1,S2) or diodes (D1,D2) are employed to trap a maximum number of magnetic flux lines in the loop when the magnetic field is impressed on the loop. Thereafter, the trapped flux is transferred from the small to the large winding to run the motor. When the switches are closed, the loop acts as a perfect conductor whereby no flux change occurs within the loop.

Superconducting motor with multiple winding rotor

A rotor assembly for a permanent magnet motor includes a set of laminations forming a rotor body, each lamination having a first magnet slot therein. A generally rectangular permanent magnet is disposed in the magnet slot, the magnet slot of each lamination being shaped so as to receive the rectangular permanent magnet through all the skewed laminations with a minimum air gap. A method of making an assembly such as a rotor includes the steps of providing an assembly body made of ferromagnetic material defining at least one magnet slot therein. The slot is at least partially filled with a mixture of magnetizable particles in a binder. The mixture is compressed and then cured, to bond the magnetizable particles together in the slot, and the bonded particles are then magnetized in the slot to form a magnet in situ in the slot without an air gap.

Laminated assemblies with in situ molded magnets

A rotor assembly for a permanent magnet motor includes a set of laminatings forming a rotor body, each lamination having a first magnet slot therein. A generally rectangular permanent magnet is disposed in the magnet slot, the magnet slot of each lamination being shaped so as to receive the rectangular permanent magnet through all the skewed laminations with a minimum air gap. A method of making an assembly such as a rotor includes the steps of providing an assembly body made of ferromagnetic material defining at least one magnet slot therein. The slot is at least partially filled with a mixture of magnetizable particles in a binder. The mixture is compressed and then cured to bond the magnetizable particles together in the slot and the bonded particles are then magnetized in the slot to form a magnet in situ in the slot without an air gap.

Growing community of inventors

Florissant, MO, United States of America

Jerry D Lloyd