Patent GB-1105570-A (GB)
Abstract: 1,105,570. Recording-apparatus. LEED & NORTHRUP CO. April 22, 1966 [May 21, 1965], No. 17826/66. Heading G1J. The print-selector mechanism (34) of the 12- point recorder disclosed in Specification 1,015,476 is replaced by a new print-selector mechanism (14) capable of selecting an angle of tilt of the print-wheel axis 11, Figs.3A, 3B, about the tilt axis 17 from three values e.g. 0, 10 and 20 degrees and the invention is characterized by the provision of a cam 167, Fig. 10, normally effective during rotation of the print-wheel 10 alternately to tilt the axis 11 between its 0 and 20 degree positions so that, with the periodic rocking of the print-wheel 10 about the printing axis 13, the two rows of symbols 1-12 and 13-24 are printed in sequence alternately on the chart 18. Synchronization. The gear ratios in trains driven by the elongated gear 45 are chosen so that (a) the print-wheel 10 performs 12 printing operations per revolution (b) the wiper arm 99 of a selector switch 97 is driven at the same speed as the print-wheel over twelve fixed contacts connected to twelve normally closed contacts of a relay 190, Fig. 26 (c) the cam 167 and cam plates 201, 202 each turn once for each 24 printing operations and (d) a notched cam 29 turns once for each 25 printing operations. Control switching. During one revolution of the print-wheel 10 a selector switch 200 is held open by cam plates 201, 202 so that a relay 190, Fig. 26, is unoperated and the wiper 97 causes the successive energization of input relays K1-K12 to switch corresponding measuring points T1-T12 into the measuring circuit 150, Fig. 10. For the next revolution the cams 201, 202 snap the switch 200 over and, provided a switch 24 has been preset closed, hold the relay 190 energized so that the wiper 97 causes the successive energization of input relays K13-K24 to switch corresponding measuring points T13-T24 into the measuring circuit 150. To convert the recorder to 12, 6, 4, 3 or 2 point operation, the switch 24 is opened to disable switch 200 and the connector 191A is plugged to the appropriate one of the groups of contacts 192A of the input relay card 193A. Alarm and control circuits as described in Specification 1, 049, 543 can be used with the recorder by connecting commutating relays KC1- KC12 and KC13-KC24, Fig.26, in parallel with input relays K1-K12 and K13-K24 respectively and associating the contact of each commutator relay with a high-low switch cam-operated from the slidewire shaft 90, Fig. 10. The print-selector mechanism, Fig. 13, includes the cam 29 with notch 30 and a cam follower 31 adjustable on a pivoted arm 27 which is biased clockwise by a spring 166 and has a pin 170 working in a slot 169 in an arm 168; while the arm 168 is linked (a) by a pin 179 and slot 180 coupling to another pivoted arm 181 carrying a follower 183 bearing on the cam 167 and (b) to the tilt shaft 26 by a coupling arm 171. The arm 171 is locked to the shaft 26 with the shaft 26 held in position for a 10 degree tilt and with the high of the cam 29 holding the arm 27 at its counterclockwise limit with the pin 170 at the large end of the slot 169. The print-selector mechanism can be preset to adapt the recorder for operation as follows:- (i) To print dots only without symbols the 10 degree tilt is held by locking the arm 27 at its counter-clockwise limit by locking a plate 177 against a bush 178 on the arm 27. (ii) To print dots with occasional symbols periodically, the plate 177 is locked in a position clear of the bush 178 leaving the arm 27 free to be swung to its clockwise limit once in each 25 printing operations when the follower 31 is lowered into the notch 30, the arm 171 changing the tilt from 10 degrees for dots only to 0 or 20 degrees according to whether the follower 183 is resting on the low or high lobe of the cam 167. (iii) To print a dot and symbol at every operation, the follower 31 is adjusted on the arm 27 so that the cam 29 cannot move it from its clockwise limit and the cam 167 alternates the tilt between 0 and 20 degrees every 24 operations. (iv) To convert to 12, 6, 4, 3, or 2 point, the arms 168 and 181 are unlinked by lifting the pin 179 out of the slot 180 and an appropriate printwheel is substituted. The recorder may then be set to print dots only or dots with symbols every time or occasionally by controlling the tilt suitably between the 10 and 0 degree positions. Shock absorbing means are included effective only in the 10 degree tilt position, Figs. 7A-9B (not shown) to reduce the impact of the printwheel when recording dots only and thus prevent perforation of the chart.