GB536527A - Improvements in and relating to recording instruments - Google Patents

Abstract

536,527. Recording-apparatus. COOL, H. R. Sept. 7, 1939, No. 25291. Convention date, Sept. 9, 1938. [Classes 106 (iii) and 106 (iv)] An instrument for use on motor vehicles comprises a uniformly driven chart carrier, and two recording styluses one of which is actuated by pendulum means responsive to the oscillations of the vehicle when in motion and the other is actuated by means operated when the speed of the vehicle exceeds a predetermined value. As shown in Figs. 1 to 3 the instrument comprises a hinged casing 10, 11 with a record disc or chart 20 driven by a clock mechanism 23. The part of the chart upon which the record is to be made is supported by a spring controlled platen 25. The primary record, showing when the vehicle is in motion, is made by a stylus 30 mounted on a pendulum lever 32. The stylus is formed with a metal point to scratch a waxed surface on the chart. An auxiliary stylus 40 for the.excess speed record is mounted on an arm 41 on a pivoted U-shaped member 42. This member co-operates with a stylus operating lever 50 on a pivoted U-shaped member 51 by means of a yielding connection comprising a leaf spring 52. A coiled spring 65 normally holds the stylus free of the chart and a finger 60, 61, prevents excessive movement of the stylus. The lever 50 is operated by the armature 73 of an electromagnet connected in circuit with the ignition system and including contacts that are opened or closed when the speed reaches a predetermined amount. Thus the record may be made after the engine has been started and up to the predetermined speed or it may be made only after the speed has been exceeded.