GB781084A - Improvements in and relating to recording devices - Google Patents

Abstract

781,084. Recording apparatus. ATTWOOD, B. G. W. Sept. 30, 1955 (Oct. 8, 1954; Feb. 22, 1955; May 25, 1955], Nos. 29059/54, 5264/55 and 15068/55. Class 106 (4). [Also in Group XXXVII] For recording the rotational position of a shaft in an electrical apparatus, e.g. of a television receiver tuning turret, an electric switch is provided adapted to be operated by the shaft together with means for moving a record member relative to a plurality of electrically actuated recording styli and control means adapted to cause the styli to produce distinctive indication on the record member in accordance with the position of the switch and in response to an electric current flowing in a conductor between an electric power source and the electric apparatus. The minute shaft 31 of a clock 12 drives by a gear 33 a gear 40 mounted between two friction discs 41, 42 and urged into driving engagement with the sprocket drum 23 of the tape 39. The take-up drum 47 is driven by a gear 52 also in mesh with the gear 33 but having balls 53 between friction discs 51, 48a to provide a lost motion as the amount of tape on the drum increases. As shown, four styli 22 of the electric type are provided and are operated in accordance with the setting of a rotary switch coupled to the shaft whose angular position is to be recorded. If recording is to be made of four or less angular positions then one particular stylus only is energized for each position. If more than four positions are to be recorded then the switch is designed to operate combinations of one or more styli for each position. Thus with the four styli shown, fifteen angular positions may be recorded. The styli are mounted on a block 60 which may be pivoted upwardly when required to change the tape. The styli may be brought into contact' with waxed paper by solenoids instead of being of the kind marking electrically sensitive paper when current passes. The friction discs 40, 42, 48a, 51 allow the position of the tape to be adjusted manually independently of the clock movement. The supply to the recording device is connected in series with the current to the apparatus being recorded so that no record is made when that apparatus is switched off.