§
Luxuse
Patent Intelligence
Sign In
Patent US4701687A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4701687A Expired / Lapsed US ⏱️ 0.0 years remaining

Controller for energization of a stepper motor

Assignee: Brother Industries Ltd
•
Filing: 1986-07-23
•
Granted: 1987-10-20
•
Expires: 2006-07-23
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The present invention provides an N phase/N+1 phase energization type stepper motor controller for alternately energizing an N number and an N+1 number of phases where N is an integer equal to or greater than one. The controller detects which phase(s) is(are) energized at a time when the stepper motor is paused, and sets a starting pulse width for N phase energization to be made shorter than that of N+1 phase energization, in response to the detected results. When the initial energization in starting is N+1 phase, a driving pulse having a width which is longer than that N phase for energization is outputted. The N+1 phase energization has stronger magnetism for rotating a rotor than N phase energization, thereby increasing the rotational speed for starting. When the initial energization is N phase, a driving pulse having a width which is shorter than that for N+1 phase energization is outputted. Thus the magnetism is made stronger so that the starting rotational speed is increased when performing either N+1 phase energization or N phase energization. The period for executing N phase energization is made shorter than that for N+1 phase energization, and the ratio of periods for N phase and N+1 phase energization is kept constant. By shortening the period for N phase energization and extending the period for N+1 phase energization, smooth and constant rotation is obtained.

Inventors

  • 👤 Satoshi Yoshimoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 14:46
CPC Classifications
H; H02; H02P; H02P8/00; H02P8/14; H02P8/18

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 138 words
An N phase/N+1 phase energization type controller for alternately energizing an N number of phases and an N+1 number of phases of a stepper motor having a rotor and a stator, N being an integer equal to or larger than 1, said controller comprising: output means for providing a determination pulse having a preset time period during which said rotor is in a pause position; memory means responsive to said output means for detecting and storing a signal indicative of the energization phase condition existing at the time of said determination pulse; control means responsive to said memory means for controlling a time period of a first pulse for N phase energization so as to be shorter than a time period of a second pulse for N+1 phase energization if said stepper motor starts on said first pulse.
Claim 2
Dependent Claim 138 words
An N phase/N+1 phase energization type controller for alternately energizing an N number of phases and an N+1 number of phases of a stepper motor having a rotor and a stator, N being an integer equal to or larger than 1, said controller comprising: output means for providing a determination pulse having a preset time period during which said rotor is in a pause position; memory means responsive to said output means for detecting and storing a signal indicative of the energization phase condition existing at the time of said determination pulse; control means responsive to said memory means for controlling a time period of a first pulse for N phase energization so as to be shorter than a time period of a second pulse for N+1 phase energization if said stepper motor starts on said first pulse.
Claim 3
Dependent Claim 19 words
A controller as claimed in claim 1 wherein said second pulse is generated after generation of said first pulse.
Claim 4
Dependent Claim 29 words
A controller as claimed in claim 2 wherein said control means controls the periods for N and N+1 phase energization to preset values after generation of said second pulse.
Claim 5
Dependent Claim 32 words
A controller as claimed in claim 1 wherein said control means controls the periods for N and N+1 phase energization to preset values if the stepper motor starts on said second pulse.
Claim 6
Dependent Claim 111 words
An N phase/N+1 phase energization type controller for alternately energizing an N number of phases and an N+1 number of phases of a stepper motor having a rotor and a stator, N being an integer equal to or greater than 1, said controller comprising: control means for controlling a time period of a first pulse for N phase energization to be shorter than a time period of a second pulse for N+1 phase energization, and for maintaining approximately constant a ratio of said time periods of said first and second pulses, said control means determining said periods of said first and second energization pulses in response to a step count number.
Claim 7
Dependent Claim 111 words
An N phase/N+1 phase energization type controller for alternately energizing an N number of phases and an N+1 number of phases of a stepper motor having a rotor and a stator, N being an integer equal to or greater than 1, said controller comprising: control means for controlling a time period of a first pulse for N phase energization to be shorter than a time period of a second pulse for N+1 phase energization, and for maintaining approximately constant a ratio of said time periods of said first and second pulses, said control means determining said periods of said first and second energization pulses in response to a step count number.
Claim 8
Dependent Claim 33 words
A controller as claimed in claim 5 wherein said control means controls said periods of said first and second energization pulses such that said periods become progressively shorter during acceleration of said rotor.
Claim 9
Dependent Claim 33 words
A controller as claimed in claim 5 wherein said control means controls said periods of said first and second energization pulses such that said periods become progressively longer during deceleration of said rotor.
Claim 10
Dependent Claim 20 words
A controller as claimed in claim 5 wherein said control means decelerates said rotor in response to a deceleration flag.
Claim 11
Dependent Claim 35 words
A controller for energization of a stepper motor as claimed in claim 5 wherein said control means maintains constant said periods of said first and second energizing pulses when driving said rotor with normal speed.
Claim 12
Dependent Claim 25 words
A controller as claimed in claim 5 wherein said stepper motor is a one-two phase energization type for alternately energizing one phase and two phases.

References Cited (Backward Citations)

GB8504061D0 Cited
US4471282A Cited
WO1985004061A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-10-19 1991-04-20 1991-10-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-10-19 1995-04-20 1995-10-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-10-19 1999-04-20 1999-10-20 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag