Motor control circuit for autofocus unit

Details Motor control circuit for autofocus unit Motor control circuit for autofocus unit

1991-04-08

1993-10-12

Shoop, Jr., William M.

Electricity: motive power systems

Open-loop stepping motor control systems

318685, 318626, 318627, 318686, H02P 800

Patent

active

052529037

ABSTRACT:
A motor control circuit for an autofocus unit which microsteps a stepping motor to turn a rotor and drive a focus lens, which circuit has a memory which stores data on current values of a plurality of phases at rotation-stopping positions of the rotor, a drive circuit which energizes the phases based on the current data output by the memory, and an address generator which reads out the current data of the memory, the address generator generating an address which makes an inclination of a path of a rotational angle with respect to a time axis smoother at a switching point of direction of rotation of the rotor, whereby the wobbling of the focus lens becomes gentler and the vibration and audio noise can be reduced.

REFERENCES:
patent: 4087732 (1978-05-01), Pritchard
patent: 4429968 (1984-02-01), Taka et al.
patent: 4612588 (1986-09-01), Tsukahara
patent: 4634949 (1987-01-01), Golladay
patent: 4652806 (1987-03-01), Aiello
patent: 4842387 (1989-06-01), Murakami et al.
patent: 4920420 (1990-04-01), Sano et al.
Patent Abstracts of Japan, vol. 15, No. 139, Apr. 1991.
Patent Abstracts of Japan, vol. 6, No. 200, Oct. 9, 1982.

Affiliated with

Also associated with

Rating

Motor control circuit for autofocus unit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Motor control circuit for autofocus unit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Motor control circuit for autofocus unit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1907218