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US5572097A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for starting polyphase dc motor

Assignee: STMicroelectronics lnc USA
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Filing: 1994-07-15
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Granted: 1996-11-05
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Expires: 2014-07-15
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Abstract

Abstract In a method for aligning a rotor of a polyphase dc motor in preparation for starting the motor. a first energization signal is applied to field coils of the motor in a first predetermined phase for a first predetermined time. Then, a second energization signal having a second predetermined phase displaced from the first phase by a predetermined amount is applied to the field coils for a second predetermined time period. In one embodiment, the second energization signal is applied to produce a maximum torque upon the rotor when the rotor is positioned at a location determined by the first energization signal. In the case of a three phase motor, the second energization signal is displaced by two commutations from the first energization signal. Circuitry for aligning a rotor of a polyphase dc motor in preparation for startup is also presented having circuitry for applying a first signal to selected field coils of the polyphase dc motor having a first commutative phase for a first predetermined time, and circuitry for applying a second signal to other selected field coils of the polyphase dc motor having a second commutative phase for a second predetermined time.

Inventors

  • 👤 Scott W. Cameron

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 06:44
CPC Classifications
H; H02; H02P; H02P6/00; H02P6/14; H02P6/16; H02P6/18; H02P6/182; H02P6/12

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 94 words
An apparatus for starting a polyphase dc motor having a rotor, a stator, and commutation circuitry wherein the commutation circuitry comprises: a start-up clock circuit having a clock output; a double align and go circuit connected to the clock output and having an align output and a go output; a logic circuit for receiving the align output and the go output, and having an increment output for generating an increment signal; and a sequencer circuit connected to said increment output for commutating a plurality of phases in said stator responsive to said increment signal.
Claim 2
Independent Claim 94 words
An apparatus for starting a polyphase dc motor having a rotor, a stator, and commutation circuitry wherein the commutation circuitry comprises: a start-up clock circuit having a clock output; a double align and go circuit connected to the clock output and having an align output and a go output; a logic circuit for receiving the align output and the go output, and having an increment output for generating an increment signal; and a sequencer circuit connected to said increment output for commutating a plurality of phases in said stator responsive to said increment signal.
Claim 3
Dependent Claim 34 words
The apparatus of claim 1 wherein said double align and go circuit comprises: a plurality of logic gates; and a plurality of flip-flops for generating a sequence of align signals and a go signal.
Claim 4
Dependent Claim 15 words
The apparatus of claim 2 wherein said plurality of flip-flops comprise three clocked R/S flip-flops.
Claim 5
Dependent Claim 23 words
The apparatus of claim 2 wherein said plurality of logic gates comprises a least one nor gate for receiving said start-up clock signal.
Claim 6
Dependent Claim 74 words
The apparatus of claim 1 wherein said logic circuit comprises: a first logic gate for receiving the go signal, and having a first output; a second logic gate for receiving the align signal and for receiving an inverted go signal, and having a second output; and a third logic gate for receiving the first output of said first logic gate and the second output of said second logic gate, for generating an increment signal.
Claim 7
Dependent Claim 14 words
The apparatus of claim 5 wherein said first logic gate is a nand gate.
Claim 8
Dependent Claim 14 words
The apparatus of claim 5 wherein said second logic gate is an nand gate.
Claim 9
Dependent Claim 14 words
The apparatus of claim 5 wherein said third logic gate is a nor gate.
Claim 10
Dependent Claim 103 words
A brushless, polyphase, direct-current motor having a rotor, stator coils, a power stage for driving stator coils, a signal interface, and a start-up circuit wherein said start-up circuit comprises: a start-up clock circuit having a clock output; a double align and go circuit connected to the clock output, having an align output, and having a go output; a logic circuit for receiving the align output and the go output, and having an increment output for generating an increment signal; and a sequencer circuit connected to said increment output for commutating a plurality of phases in said stator coils responsive to said increment signal.
Claim 11
Dependent Claim 103 words
A brushless, polyphase, direct-current motor having a rotor, stator coils, a power stage for driving stator coils, a signal interface, and a start-up circuit wherein said start-up circuit comprises: a start-up clock circuit having a clock output; a double align and go circuit connected to the clock output, having an align output, and having a go output; a logic circuit for receiving the align output and the go output, and having an increment output for generating an increment signal; and a sequencer circuit connected to said increment output for commutating a plurality of phases in said stator coils responsive to said increment signal.
Claim 12
Dependent Claim 35 words
The apparatus of claim 9 wherein said double align and go circuit further comprises: a plurality of logic gates; and a plurality of flip-flops for generating a sequence of align signals and a go signal.
Claim 13
Dependent Claim 15 words
The apparatus of claim 10 wherein said plurality of flip-flops comprise three clocked R/S flip-flops.
Claim 14
Dependent Claim 21 words
The apparatus of claim 10 wherein said plurality of logic gates comprise a nor gate for receiving said start-up clock signal.
Claim 15
Dependent Claim 77 words
The apparatus of claim 9 wherein said logic circuit comprises a first logic gate for receiving a delay counter signal and for receiving the go signal, and having an output; a second logic gate for receiving the align signal and for receiving an inverted go signal, and having an output; and a third logic gate for receiving the output of said first logic gate and the output of said second logic gate, for generating an increment signal.
Claim 16
Dependent Claim 14 words
The apparatus of claim 13 wherein said first logic gate is a nand gate.
Claim 17
Dependent Claim 14 words
The apparatus of claim 13 wherein said second logic gate is an nand gate.
Claim 18
Dependent Claim 14 words
The apparatus of claim 13 wherein said third logic gate is an nor gate.
Claim 19
Independent Claim 85 words
A method for starting the rotation of a polyphase dc motor in a disk drive comprising the steps of: generating a first align signal using a double align and go circuit to energize a first dual coil mode commutation phase; generating a second align signal using the double align and go circuit to energize a second dual coil mode commutation phase; and generating a go signal using the double align and go circuit to enable a start-up algorithm for the normal commutation sequence to proceed.
Claim 20
Independent Claim 85 words
A method for starting the rotation of a polyphase dc motor in a disk drive comprising the steps of: generating a first align signal using a double align and go circuit to energize a first dual coil mode commutation phase; generating a second align signal using the double align and go circuit to energize a second dual coil mode commutation phase; and generating a go signal using the double align and go circuit to enable a start-up algorithm for the normal commutation sequence to proceed.
Claim 21
Dependent Claim 25 words
The method of claim 17 wherein the step of generating a second align signal comprises energizing a predetermined phase whereby a maximum torque is created.
Claim 22
Dependent Claim 25 words
The method of claim 17 wherein the step of generating a second align signal comprises energizing a phase two commutation steps from said first phase.

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