GB979375A - Digital printer - Google Patents

Abstract

979,375. Recording-apparatus. BECKMAN INSTRUMENTS Inc. Sept. 20, 1963 [Nov. 30, 1962], No. 37019/63. Heading G1J. Apparatus for making a record of an electrical quantity in the form of a higher order digit or number and an adjacent lower order digit comprises a potentiometer 11 controlled by a servo system 10 that is mechanically connected to the moving arm 23 and to a hundreds and tens print drum 46 attached to a wheel 47 with a notch 50 for each position 49 adapted to co-operate with a pawl 54; a solenoid 55 responsive to a print command switch 56 for bringing the pawl 54 to a position in which it can engage a notch and a switch 94 for applying a signal to the servo system so as to move the drum 46 until the pawl 54 engages a notch 50 whilst simultaneously moving a units sector 72 in correspondence with this movement of the drum 46. With the switch 28 in the position shown the servo system positions the drum 46 in accordance with a variable applied to the terminals 14,15. When switch 56 is closed, switch 28 shorts half the control winding of the shaded pole type motor 10 which turns the drum 46 back till a number 49 reaches the printing position and the pawl 54 locks it there, stalling the motor 10. Closing switch 56 also operates clutch 63 to couple the drive to sector 72. After a sufficient delay controlled by circuit 102, a pawl 75 locks the sector 72 through teeth 74 on disc 73 and print hammers 86, 87 cause an impression to be made on record sheet 90. The constant speed drive to sheet 90 may be used to control the print command switch 56 if records are required at regular intervals of time. If a graphical record is also required the movement of the drum 46 may be transmitted to a pen 171,Fig.3, carried by a block 172. An alternative mechanical transmission between drum 46 and sector 72 is described, Fig. 2 (not shown).