Patent · US Expired

Apparatus for distance control

US3970911A · kind A · utility

10Cited by
8References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 14, 1974
Grant dateJul 20, 1976
Priority date
Expiry dateJun 14, 1994

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23K7/102
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

The distance between a cutting torch and a work piece varies the oscillating frequency of the electrical control circuit. This frequency is converted by a discriminator into direct current signals, which are utilized to correct the deviations and hold the torch at a substantially constant distance from the work piece. As the torch moves away from the work piece, the bandwidth of the discriminator is widened, such as by damping or untuning a discriminator tuning circuit. A field-effect transistor is suitable for use as a damping resistor, and a capacitor-diode unit may be used to untune the tuning circuit. The control voltage is conveniently tapped from the output of an amplifier connected to the discriminator, and the control input may be provided to a variable resistor or capacitor. The control voltage for changing the frequency range is conveniently obtained from the analog signal component of the regulator output.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.