Integral motor and control

A high-efficiency low-power integrated evaporator fan motor and control assembly particularly adapted for use in a refrigerated environment to circulate cooling air within the enviornment, the assembly comprising:

• an electronically commutated DC motor;
• A circuit board including a plurality of electronic components and interconnections thereof;
• said electronically commutated motor including a stator core, a permanent magnet rotor and at least one winding wound on a multifunction bobbin and magnetically coupled to said stator core;
• said bobbin being positioned on and connected with said circuit board;
• housing means positioning and supporting said motor and electronic components therewithin;
• and
• a Hall sensor connected to components on said circuit board and positioned in magnetic coupling relationship with said permanent magnet rotor to sense rotation thereof;
• said assembly including a DC power supply, and switching means to provide power from said DC power supply to said at least one or more winding in response to signals from said Hall sensor;
• and
• said control circuit including means to pulse the energizing power supplied to said windings through said switching means, thereby to decrease the energizing power and to increase the power efficiency of said assembly.

An electronically commutated integrated motor and control assembly particularly suitable for use in air moving applications comprising:

• a stator core with at least one winding disposed thereon;
• a permanent magnet rotor adapted to rotate about an axis of rotation in response to rotating magnetic fields in the stator core;
• means for developing a position control signal indicative of the rotational position of said rotor;
• said means for developing a position control signal including a sensor positioned adjacent the rotor for generating a control signal responsive to the rotational position of said rotor;
• means for energizing said at least one winding in a predetermined sequence in response to the position control signal;
• and
• a control circuit for connecting power, through switching means, to provide power pulses to periodically energize said at least one winding during those periods of generation of higher rotational torque, and for inhibiting the supply of power to the at least one winding during at least part of that portion of each revolution of the rotor that lower rotational torque is being generated thereby to provide increased operating efficiency.

A motor and control assembly comprising:

• a C-frame stator core with a plurality of winding turns disposed adjacent said stator core;
• a permanent magnet rotor including at least one pair of magnetic poles adapted to rotate in a bore in said stator core in response to rotating magnetic fields established within said stator core by sequential energization of said winding turns;
• a Hall sensor for developing a position control signal responsive to the rotational position of said rotor;
• means for generating a pulsed control signal, responsive to said position control signal, for energization of winding turns in a predetermined sequence to provide pulsed torque to said rotor;
• said means to generate said pulsed control signal including means to turn off the energization of selected winding turns during at least a portion of the period when the rotational torque produced by energization of said selected winding turns is decreasing from a maximum value.

A method of operating a motor with increased efficiency, the motor comprising an electronically commutated motor having a stator core with a plurality of winding turns disposed about said stator core, a permanent magnet rotor mounted for rotation about an axis of rotation within a bore formed in said stator core, and a control circuit for the energization of said windings, the method comprising:

• energizing a Hall sensor with pulses derived from said control circuit;
• sensing the output of the Hall sensor during the period of said pulses to provide a control signal indicative of the angular position of the permanent magnet rotor;
• and
• sequentially energizing winding turns in response to said control signal in a predetermined sequence to cause rotation of the rotor;
• whereby power consumption by said assembly is reduced during periods between said pulses of electric power to the Hall sensor.

A high-efficiency low-power electronically commutated integral motor and control comprising:

• a stator core with a plurality of windings disposed adjacent said stator core;
• a permanent magnet rotor adapted to rotate about an axis of rotation in response to a rotating magnetic field established within said stator core;
• means for developing a position control signal in response to the rotational position of said rotor;
• said means for developing a position control signal including a Hall sensor positioned adjacent said stator core, energized by a source of electrical power, and magnetically coupled to said permanent magnet rotor to generate a signal responsive to the position of said rotor;
• means for energizing the windings in a predetermined sequence in response to the position control signal;
• the source of electrical power being connectable to the Hall sensor through means which provide power pulses to periodically energize the Hall sensor;
• said power pulses being shorter in duration than the time between pulses;
• and
• protective means operable during fault conditions to protect said motor from overheating damage.

A brushless direct current fan motor and control circuit, comprising:

• a skeleton frame stator core including a bore, and a plurality of winding turns carried by the core;
• a permanent magnet rotor adapted to rotate about an axis of rotation within said bore in response to a rotating magnetic field established about said rotor;
• a sensor for generating a position control signal responsive to the position of said rotor;
• means for generating said rotating magnetic field in a predetermined sequence in response to said position control signal to cause rotation of said rotor;
• an integrated control circuit for pulsing power to said winding turns only during the higher efficiency portion of the periods available for pulsing power to said winding turns to obtain rotation of said rotor, and for inhibiting the application of power to at least some of the winding turns during at least part of the periods for pulsing power to said winding turns;
• said at least part of the periods comprising intervals of lower magnetic coupling efficiencies between the rotor and stator;
• an alternating current power source;
• a first rectifier circuit to provide direct current for the windings of said direct current motor;
• and
• a second rectifier circuit to provide direct current for said control circuit;
• and
• means to protect said motor under abnormal operating conditions.