GB1372995A - Recording apparatus - Google Patents

Abstract

1372995 Recording-apparatus UNIVERSITY OF MELBOURNE 11 Oct 1971 [12 Oct 1970] 47287/71 Heading G1J Apparatus for recording electrically transmitted signals comprises (a) mechanism 24, 26 on a frame 13 for continuously advancing a strip 14 of material over a backing roller 18 where a stylus 43 applies heat and pressure thereto, the material producing directly readable markings the intensity of which increases with increased application of pressure by the stylus and the stylus being carried by a sleeve 41 slidably and pivotally movable on a transverse rod 39 adjacent the roller 18, (b) mechanism 45, 46 for systematically moving the sleeve 41 to carry the stylus across the width of the strip 14 and (c) a bearing plate 67 bearing on the sleeve 41 to apply presn sure between the stylus 43 and roller 18 and a relay disposed to draw the plate 67 in the direction to apply such pressure, the relay being energisable in direct proportion to the intensity of the signals to be recorded. The strip 14 is driven by a supply roll 15 to be taken up on a spindle 32, passing over the silver steel roller 18 and hinged plate 19 to be gripped by a metal roller 30 and a rubber roller 24 driven by an electric motor 26 thorugh a one-way clutch 25 which allows the roller 24 to be turned forwardly by a knurled knob 29. A belt 45 moves the sleeve 41 and stylus 43 towards a post 37 when the output shaft 50 of a magnetic clutch 49 is driven by an electric motor 46 coupled to a gear box 48 connected to the input shaft of the clutch 49. When the sleeve 41 depresses the pin 59 of a micro-switch 58 the clutch 49 is disengaged and a retracting band (56), Fig.3 (not shown) moves the belt 45 to return the sleeve 41 to its starting position. The switch 58 also releases the pressure of the plate 67 on the stylus 43. Upward displacement of the plate 67 is restricted by a bridge piece 71 held in slots 72 in side walls 61 by screws 73 and adjustable by a screw 74. The material of the strip 14 is made heat pressure-sensitive by sticking a layer of tough, black, heat-resistant paper to a paper base and superimposing a thin opaque film of cellulose and wax. The stylus 43 is made from electrical resistor wire suitably bent for contact with the paper and heated by passing an electric current therethrough under the control of a rheostat 84 having an adjusting screw 83. The film is eroded by melting and/or pressure which reduces its thickness and enhances the degree of blackness to be observed.