GB720086A - Improvements in indicating and measuring instruments - Google Patents

Abstract

720,086. Indicating-apparatus ; barometric gauges. DEWRANCE & CO., Ltd. Nov. 29, 1951 [Dec. 1, 1950], No. 29461/50. Classes 106 (2) and 106 (4). An indicating-instrument comprises a movement mounted on a dial for transmitting movement from an actuator to an index and setting regulating means adapted by effecting movement of the dial relative to the actuator and to a casing or base upon which the dial is mounted to effect adjustment of the setting of the index relative to the dial. The invention is shown applied to a pressure gauge wherein bellows 27, Fig. 2, communicate with a source of pressure through a channel 31 in a supporting block 30, a pipe 32, and channel 12 in a base 9, which change of pressure causes axial movement of a rod 35 in hooked engagement with an arm 50, Fig. 6, of a rod 48 pivoted in bearings on a plate 39, Fig. 3, while a second arm 51 engages an arm 54 bearing a toothed sector 56 pivoted on a second plate 38 and engaging a spring-urged gear-wheel 58 on the spindle 47 of the index pointer 2. The plates 38, 39 bearing the movement parts 48, 56 are spaced apart and supported by a dial 4 formed by a thin metal disc clamped by screws in pillars 16 extending forwardly from the base 9. The pointer 2 is moved relative to the dial for zero adjustment by causing the movement to approach or recede from the bellows 27 which is achieved by flexing the dial 4 by means of a screw-threaded adjuster rod 21 either against a spring 5 or against the resilience of the dial itself if suitably mounted on inclined ends of the pillars 16. A removable plug 66 is provided in the outer casing to give access to the rod 21.