Patent GB-777998-A (GB)
Title: Improvements relating to control apparatus for operation of pattern reproducing machines
Inventor: STEPHAN HALLIS NOAH
IPC: B23B39/02
Filed: 1955-04-18
Abstract: 777,998. Electric copy-milling machines. NEW BRITAIN MACHINE CO. April 18, 1955, No. 11079/55. Class 40 (1). [Also in Groups XXII and XXXVII] A horizontal boring, drilling and milling machine having a spindle carrying a tool and feeler gauge adapted for vertical movement, and a table and saddle carrying a workpiece and pattern adapted for horizontal movement in two mutually perpendicular directions is associated with a multi-position switch whereby two of the motors producing the three directions of relative movement may be controlled by the feeler gauge and the third produces a to-andfro movement at a manually-controlled speed, or all three motors may be manually controlled. As shown, Fig. 1, the machine has a spindlehead C and back-rest E, vertically movable jointly by a motor 46, the spindle 12 being rotatable in opposite directions by a variablespeed motor in the machine bed. A reversible rapid traverse motor is carried on the head C. The spindle may also be driven by a hand wheel 25 and its position is indicated by a dial mechanism H. The speed of rotation of the spindle may be controlled through gearing or by adjustment of a potentiometer in the supply circuit, with associated " Jog " buttons. The feed is controlled in either direction by illuminated push-buttons, and is stopped by an individual " Stop " button, or by a " Stop-all " button, the buttons being mounted on a control pendant I, The spindle feed relative to its rotational speed is set by gear shift levers 36, 37. Vertical movement of the spindle head C and back-rest E is indicated on a dial J through which the head and rest can be moved manually. The saddle F is moved by a reversible, variable speed motor 58 and the table G by a similar motor 62, their movements being indicated by a dial K and dials M and N. Levers 64, 65 control the clamping of the head, back-rest and table. Manual control.-The motors 46, 58, 62 are each controlled in a similar manner by switches and potentiometers in the pendant I. The A.C. supply at 66, 67 (Fig. 9) is rectified and fed to a potentiometer 73, the magnitude of the D.C. output, which is taken to one of the motors, being determined by the position of the slider 76, and the polarity by a double-pole switch 82 operated by a cam 79 on the shaft of potentiometer 73. Automatic control for copying.-A detachable rail 104, fixed to the spindle head C and backrest E, carries a tool head U and tool 111 driven by a shaft 112 from the main spindle 12, and also a tracer head V. The signal from the tracer is fed to a detector unit 116 (Fig. 7) energized by oscillator 120, a derived voltage being amplified at 121 and fed through a multi-position switch Y for controlling motors 46, 58, 62, the changeover from manual to automatic control being effected by a triple plug T, T<SP>1</SP>, T<SP>11</SP> when inserted into jacks S, S<SP>1</SP>, S<SP>11</SP>. The position of switch Y determines whether a motor shall be controlled by the sine or cosine component of the signal from bridge 116, or by the manual setting of potentiometer 73, the connections being such that when the tracer touches a conducting strip 207 or 208 located on either side of the template 210, the direction of travel of the saddle F is reversed, or strips 207, 208 may be by-passed by operating a switch 216 and movement of saddle F controlled manually.