Washing machines having motor braking circuits

Abstract

A washing machine is provided that includes a motor, an inductive winding device, a motor control unit, and a braking circuit. The motor control unit is in electrical communication with the motor and the inductive winding device. The braking circuit is in electrical communication with the inductive winding device and the motor control unit. The braking circuit dissipates a braking energy from the motor through the inductive winding device and the motor control unit controlling the braking energy so as to avoid activation of the inductive winding device.

1 . A washing machine comprising:
 a motor;   an inductive winding device;   a motor control unit in electrical communication with said motor and said inductive winding device; and   a braking circuit in electrical communication with said inductive winding device and said motor control unit, said braking circuit dissipating a braking energy from said motor through said inductive winding device, and said motor control unit controlling said braking energy so as to avoid activation of said inductive winding device.   
   
   
       2 . The washing machine as in  claim 1 , wherein said inductive winding device comprises a solenoid of a mode shifter and said braking circuit comprises a mode-shifting braking circuit. 
   
   
       3 . The washing machine as in  claim 1 , further comprising an agitator driven by said motor. 
   
   
       4 . The washing machine as in  claim 3 , wherein said agitator rotates about a vertical axis. 
   
   
       5 . The washing machine as in  claim 1 , wherein said motor comprises a three-phase alternating current induction motor. 
   
   
       6 . The washing machine as in  claim 5 , wherein said motor control unit is integral with said three-phase alternating current induction motor. 
   
   
       7 . The washing machine as in  claim 1 , wherein said braking circuit is resident on said motor control unit. 
   
   
       8 . A washing machine comprising:
 a motor;   a motor control unit in electrical communication with said motor;   a mode shifter controlled by said motor control unit between a first state and a second state;   a basket and an agitator configured to be driven by said motor via said mode shifter, said basket being driven by said motor when said mode shifter is in said first state, said agitator and said basket being driven by said motor when said mode shifter is in said second state; and   a mode-shifting braking circuit resident on said motor control unit, said mode-shifting braking circuit dissipating a braking energy from said motor through said mode shifter only to a level sufficient to maintain said mode shifter in said second state.   
   
   
       9 . The washing machine as in  claim 8 , wherein said basket and said agitator are configured to be driven by said motor about a vertical axis. 
   
   
       10 . The washing machine as in  claim 8 , further comprising a transmission for transmitting a rotary force from said motor to said mode shifter. 
   
   
       11 . The washing machine as in  claim 8 , wherein said mode shifter comprises a solenoid and said mode-shifting braking circuit dissipates said energy through said solenoid. 
   
   
       12 . The washing machine as in  claim 8 , wherein said agitator and said basket rotate about a vertical axis. 
   
   
       13 . The washing machine as in  claim 8 , wherein said motor comprises a three-phase alternating current induction motor. 
   
   
       14 . The washing machine as in  claim 13 , wherein said motor control unit is integral with said three-phase alternating current induction motor. 
   
   
       15 . A method of controlling a washing machine during a braking operation, comprising:
 dissipating a braking energy from a motor generated during the braking operation through an inductive winding device only to a level sufficient to maintain said inductive winding device in an un-activated state.   
   
   
       16 . The method as in  claim 15 , wherein said inductive winding device comprises a solenoid such that dissipating step comprises dissipating said braking energy through said solenoid to a level sufficient to maintain said solenoid in said un-activated state.