Stepping motor closed loop constant velocity control system
US4103216A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 28, 1976 |
| Grant date | Jul 25, 1978 |
| Priority date | — |
| Expiry date | May 28, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P23/22
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A closed loop control system for controlling the rotational velocity of a stepping motor during a period of continuous shaft rotation such that the velocity remains constant is disclosed. Step response signals are developed for each step increment of movement of the shaft of the stepping motor. The step response signals are used to control the counting of clock pulses by a counter, resulting in the production of measured inter-step time (T.sub.t) data. The T.sub.t data is gated to a controller functioning in accordance with the equation [2D.sub.t-1 + (T.sub.nom - T.sub.t)]/2, to produce step delay control (D.sub.t) data, where D.sub.t-1 data is the step delay control data for the previous step and T.sub.nom data is predetermined nominal inter-step time data. Each newly developed D.sub.t data is used to preset a counter that controls the production of the next motor stepping control pulse, and becomes D.sub.t-1 for the next calculation. Separate D.sub.t data is developed for both the clockwise and counter-clockwise directions of rotation of the stepping motor shaft.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.