Speed control apparatus for A.C. elevator

Details Speed control apparatus for A.C. elevator Speed control apparatus for A.C. elevator

1987-04-01

1988-05-24

Shoop, Jr., William M.

Elevator, industrial lift truck, or stationary lift for vehicle

Stationary lift for roadway vehicle or required component...

Having specific drive means for support

318801, B66B 130, H02P 540

Patent

active

047459913

ABSTRACT:
A speed control apparatus for an A.C. elevator according to this invention comprises integration circuits which integrate outputs of current detectors for detecting primary currents of an induction motor and which are reset at fixed periods, and holding circuits which hold outputs of the integration circuits for a predetermined time. Thus, the influences of the ripples of the currents by pulse width modulation are eliminated, and the digital conversions of the three-phase currents can be performed by a single analog-to-digital converter.

REFERENCES:
patent: 4230979 (1980-10-01), Espelage et al.
patent: 4456868 (1984-06-01), Yamamura et al.
patent: 4459534 (1984-07-01), Nagase et al.
patent: 4503375 (1985-03-01), Okuyama
patent: 4625834 (1986-12-01), Tanahashi
patent: 4671389 (1987-06-01), Tanahashi
patent: 4677361 (1987-06-01), Yonemoto
patent: 4681191 (1987-07-01), Ikejima

Affiliated with

Also associated with

Rating

Speed control apparatus for A.C. elevator does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Speed control apparatus for A.C. elevator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Speed control apparatus for A.C. elevator will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1053734