Browse Prior Art Database

Sensing for Torque Motor Speed

IP.com Disclosure Number: IPCOM000095929D
Original Publication Date: 1964-Oct-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 26K

Publishing Venue

IBM

Related People

Rutter, DE: AUTHOR

Abstract

The speed changes of a torque motor in a reeling application can be indicated by sensing variations in the motor field current. In A, paper tape 1 is withdrawn from supply reel 2 and fed past scanner 3 by intermittently operated feed rolls 4. Unrolled tape is fed through guides 5 automatically onto take-up reel 6 rotated by torque motor 7. During the rewind process, motor speed is monitored by the circuit in B which produces an output voltage useful for control signals.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Sensing for Torque Motor Speed

The speed changes of a torque motor in a reeling application can be indicated by sensing variations in the motor field current. In A, paper tape 1 is withdrawn from supply reel 2 and fed past scanner 3 by intermittently operated feed rolls 4. Unrolled tape is fed through guides 5 automatically onto take-up reel 6 rotated by torque motor 7. During the rewind process, motor speed is monitored by the circuit in B which produces an output voltage useful for control signals.

In the circuit, resistor 8 is added in series with the motor field winding 9 and capacitor 10, all in parallel with armature winding 11. As motor speed changes due to tape threading or breakage, the voltage change across resistor 8 appears across coupling capacitor 12 and is rectified by half-wave rectifier network. This includes diode 13, resistor 14 and capacitors 15.

The rectified current produces a signal at voltage divider network of variable resistor -16 and fixed resistor 17. Variable resistor 16 can be set to provide an output signal of either polarity, when the motor is operating at full speed. Output 18 can be connected to a voltage discriminator to open guides 5, when the tape is threaded onto reel 6 or to actuate an alarm when the tape breaks.

1

Page 2 of 2

2

[This page contains 2 pictures or other non-text objects]