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US 4,378,520 AGranted
D-C Relay relief control for A-C electric motor
OwnerHorace B. Fordinventor
Life of this patent
Estimating the term…
Abstract
A D-C relay control is employed for a single phase induction motor for disconnecting the starting capacitors and/or starting windings from the main windings as the motor speed increases upon start up. D-C for the relay control is obtained from a rectifier coupled to the starting windings.
Claims10
An A-C motor, comprising:
- main electrical windings,
- starting electrical winding means coupled to said main electrical windings,
- starting capacitor means coupled to said starting electrical winding means,
- normally open contact means coupled to said starting capacitor means and to said main electrical windings,
- electrical coil means and normally closed relay contacts coupled to said main electrical windings,
- said electrical coil means closing said normally open contact means when energized,
- rectifier means coupled across at least a portion of said starting electrical winding means for converting A-C power to D-C power, and
- a relay coil coupled to the output of said rectifier means for opening said relay contacts when a predetermined level of D-C voltage is applied to said relay coil for de-energizing said electrical coil means whereby when line voltage is applied to said main electrical windings, said electrical coil means is energized allowing the motor to start and when said predetermined level of D-C voltage is applied to said relay coil, said relay coil opens said relay contacts resulting in said electrical coil means becoming de-energized disconnecting at least said starting capacitor means from said main electrical windings.
5 more elements
An A-C motor, comprising:
- main electrical windings,
- starting electrical winding means coupled to said main electrical windings,
- starting capacitor means coupled to said starting electrical winding means,
- normally open contact means for connecting and disconnecting said starting capacitor means and said starting electrical winding means to and from said main electrical windings,
- electrical coil means and normally closed relay contacts coupled to said main electrical windings,
- said electrical coil means closing said normally open contact means when energized,
- rectifier means coupled across at least a portion of said starting electrical winding means for converting A-C power to D-C power, and
- a relay coil coupled to the output of said rectifier means for opening said relay contacts when a predetermined level of D-C voltage is applied to said relay coil for de-energizing said electrical coil means whereby when line voltage is applied to said main electrical windings, said electrical coil means is energized allowing the motor to start and when said predetermined level of D-C voltage is applied to said relay coil, said relay coil opens said relay contacts resulting in said electrical coil means becoming de-energized, disconnecting said starting capacitor means and said starting electrical winding means from said main windings.
5 more elements
An A-C motor, comprising:
- main electrical windings,
- starting electrical winding means coupled to said main electrical windings,
- starting capacitor means coupled to said starting electrical winding means,
- normally closed relay contacts coupled to said starting capacitor means and to said main electrical windings,
- rectifier means coupled across said starting electrical winding means for converting A-C power to D-C power, and
- a relay coil coupled to the output of said rectifier means for opening said relay contacts when a predetermined level of D-C voltage is applied to said relay coil whereby when line voltage is applied to said main electrical windings, the motor will start and when said predetermined level of D-C voltage is applied to said relay coil, said relay coil opens said relay contacts disconnecting at least said starting capacitor means from said main electrical windings.
3 more elements
An A-C motor, comprising:
- main electrical windings,
- starting electrical winding means coupled to said main electrical windings,
- normally closed relay contacts for connecting and disconnecting said starting electrical winding means to and from said main electrical windings,
- rectifier means coupled across said starting electrical winding means for converting A-C power to D-C power, and
- a relay coil coupled to the output of said rectifier means for opening said relay contacts when a predetermined level of D-C voltage is applied to said relay coil whereby when line voltage is applied to said main electrical windings, the motor will start and when said predetermined level of D-C voltage is applied to said relay coil said relay coil opens said relay contacts disconnecting said starting electrical winding means from said main electrical windings.
2 more elements
Dependencies are inferred from the claim text.