GB665219A - Improvements in or relating to means for indicating and recording the value of a physical variable - Google Patents

Abstract

665,219. indicating and recording apparatus. YOXALL, L. S. (Foxboro Co.). June 16, 1949, No. 16094/49: Class 106 (iv). Recording-apparatus wherein a pen on a pivoted arm makes a continuous record of a variable on a rotating circular chart is provided with an indicator readable at a distance comprising a scale plate mounted within the ambit of the circular chart and extending from edge to edge thereof and a pointer co -operating therewith and linked with the pen arm to move therewith, the pen arm being pivoted on the same side of the scale as the pointer and projecting to the remote side of the scale plate so that the record is visible when made and thereafter for the greater part of the travel of the chart. A pen arm 14 is angularly positioned to indicate and record temperature on a chart 12 rotating counterclockwise and a pointer 18 linked thereto also indicates the temperature against a scale 20 which may cover a different range from the chart and is preferably provided with large numbers. The scale plate 16 has slots 48, 50 and is held by screws 44, 46 so as to be vertically adjustable for calibration, 'while the pointer 18, counterweighted at 56, is rigid with a spindle 54 mounted freely in a bracket 52. The pointer 18 and pen arm 14 are linked by means of a lever 58 fixed to the spindle 54 and connected to a ball-tip link 60 which engages a hole 68 in a member 62 fitted on a rivet 64 on the pen arm 14 and prevented from turning relative thereto by its end bent through a hole 66. The upper end 70 of the pen arm 14 is forked and engages a stud 72 on an extension 36 of a bracket 32 which pivots in accordance with temperature, the extension 36 being forked at its lower end to engage a part 74 of the rivet 64 in the pen arm 14. Specifications 622,788, [Group XXV], and 622,868 are referred to.