Patent GB-351035-A (GB)
Title: Printing mechanism for use with meters and other measuring instruments
IPC: G01R11/58
Filed: 1930-03-12
Abstract: 351,035. Recording apparatus for meters &c. FERRANTI, Ltd. and HOLMES, W., Hollinwood, Lancashire. March 12, 1930, No. 8071. [Class 106 (i).] Counters with recording apparatus.-The movements of the spindle of a meter or other measuring instrument are registered on a counting device by means of impulses received from such movements and the counter is geared, through a spring storage device, to a set of type-wheels from which an impression can be taken on a record-strip periodically under the control of a time switch, the impulses received during the printing and resetting operation of the type-wheels being stored in the spring device. In the form shown in Figs. 1, 2 and 3, the impulses transmitted from the meter &c. are received by an electromagnet 1 the armature 2 of which is rocked to operate a pair of reversely acting pawls 4, 5 actuating a ratchet wheel 6 loosely mounted on a shaft 7. The ratchet wheel 6 is connected by a gear train to a counting device 8 and is also connected to a wheel 11 through a spring storage device disposed within a casing on the wheel 11. Integral with the wheel 11 is a ratchet wheel 13 and a pawl 19 which drives the units wheel of a set of type-wheels 15 .. 18 loosely mounted on the shaft 7 and interconnected by transfer pinions 20. A clockwork movement (not shown) periodically energizes a relay 9 to close the contacts 9b in the circuit of a motor 32 and at the same time energizes a brake-release electromagnet 51 to permit the motor to start. The motor, through a shaft 31 and gearing, drives a shaft 23 carrying a set of cams 25 . . 30. The cam 25 comprises a single notched disc which serves to maintain the contacts 9b closed during one revolution of the shaft 23. The cam 29, Fig. 6, controls a pawl 14 adapted to lock the ratchet wheel 13 during the printing operation the impulses during this period being stored in the spring device. The cam 28, Fig. 8, serves to control a set of prongs 37 and a fork 38 to hold the type-wheels in adjusted position. The cam 26, Fig. 3, co-operates with an ink-ribbon carrier frame 33 to set the ink ribbon in front of the type-wheels. On removal of the frame a pawl thereon actuates a ratchet wheel to advance the ink ribbon. Through the action of the cam 27, Fig. 3, a frame 35 carrying the impression hammers 36 is actuated to effect the record on a paper strip 55 which passes over a feed roll 41 to a receiving drum 43 connected to the feed roll by gearing and a friction clutch. The strip 55 is advanced by a ratchet-and-pawl device 42 operated by the cam 30. After the printing operation the prongs 37 and fork 38 are withdrawn and a mutilated pinion 24, on a shaft geared to the cam shaft 23, actuates a pinion 22 on the shaft 7 which is thereby rotated to zeroize the type-wheels a longitudinal slot in the shaft picking up pawls on the wheels in the known manner. During this operation a cam 50 is effective to disengage the transfer pinions 20. When the ratchet wheel B is again released the energy stored in the spring device is liberated to actuate the typewheels the movement being under the control of an air vane or fly 112. In order to vary the reading obtainable for each impulse transmitted the units type-wheel is so designed that one-tenth of a revolution corresponds to the number of desired units, the numerals being set out in accordance with the units figures of the partial products of the digits multiplied by the factor desired. Additional transfer pins or teeth are also provided on the wheel. The units wheel, where one-tenth of a revolution represents three units, is shown in Fig. 16, three sets of transfer pins 58 being provided.