477,367. Typewriters &c. BALDWIN, R. E. June 27, 1936, No. 17908. [Class 100 (iv)] [Also in Group XIX] Exhaust of paper, indicating ; locking-devices. -Means for stopping a statistical or like printing-machine when a sheet has been filled with items comprises main and auxiliary sheet-sensing devices so arranged that stopping is initiated when they sense the absence and presence of the sheet respectively. The main device may co-operate with a marginal perforation in the sheet. As applied to keyboard machines, the stopping-means may be arranged to lock the keyboard. The mechanism shown in Fig. 1 is embodied in a record-controlled tabulating-machine having the sheet-feeding apparatus described in Specification 422,344. The mechanism comprises a yoke 4 pivoted at 2 and having main and auxiliary fingers 6, 7 for engaging a sheet as it passes from the platen P over a table 1. The yoke is held by means of a spring 9c in engagement with a pin 9d on a bell-crank 9a secured to a shaft 8. The shaft is connected by a link 11 and lever 13 to a link 15 having a fork 15a engaging a pin 16 on a rock-arm 17 which is provided with a roller engaging a cam 12. A latch 19 mounted on the pin 16 normally abuts on a shoulder 20 on the link 15 and is thereby prevented from co-operating with the stopping- lever 21 of the machine. During each cycle, the bell-crank 9a causes the yoke 4 to descend, and normally the finger 6 engages an unperforated part of the sheet, the yoke is arrested in such a position that a lug 4b thereon ‹is prevented from obstructing a lug 9e on the bell-crank, and the bell-crank and links 11, 15 make a full stroke. When, however, the end of the sheet reaches the printing line, the finger 6 passes through a marginal perforation in the sheet, the yoke is arrested by engagement of the finger 7 with the sheet, the lug 4b obstructs the lug 9e, the stroke of the bell-crank and links is so shortened that the latch 19 is permitted to engage a lug 21a on the stopping-lever 21, and on return of the cam 12, the latch raises the stopping-lever and the machine is stopped. When there is no sheet in the machine, the bell-crank 9a is not obstructed by the yoke 4, and the machine continues to operate. If it is required to print on both sides of a sheet, each margin is provided with a perforation. A button 23 for starting the sheet-feeding apparatus, and, subsequently, the adding and printing mechanism is connected to a pivoted plate 24 having a lug 26 co-operating with a lug 27 on a spring-urged link 28 which is suspended from a pivoted arm 30. A slot in the ,link 28 engages a pin 34 on a spring-urged pivoted arm 35 having a pin 37 for engaging the stoparm 60 of the sector 100, described in the above-mentioned Specification, for rotating the platen and feed-rollers to eject one sheet and feed-in another. The pin 34 normally abuts on a latch 40. The plate 24 co-operates with a spring-urged latch 41 which has a slot engaging a stud 44 and abuts at the top on a pin 42. The sector 100 is connected by a link 101, Fig. 8, to a bell-crank 102, 104 carrying a roller 105 which co-operates with a cam 106 on a shaft 63. A clutch for the shaft comprises a disc 64 provided with a pivoted arm 65 having a roller 66 for engaging a nose 61 on a driven worm-wheel. The arm 65 engages a bell-crank mounted on the disc and provided with a pin 70 engaging a hole in a rocking plate 67 also mounted on the disc. The rocking plate co-operates with fingers on a rocking yoke 75 connected by a link 80 to a link 49, Fig. 1, for starting the adding and printing mechanism. When the button 23 is depressed, the plate 24 displaces the link 28, the latch 41 rocks about the pin 42, and a lug 46 on the latch holds the plate, and consequently the button and link, in displaced position. Towards the end of the upward movement of the link 101, a projection thereon releases the latch 40, the arm 35 permits the stop-arm 60 to release the segment 100, and the platen is rotated to feed the sheet. Towards the end of the feed-movement, the segment rocks the latch 41 about the stud 44, a nose 41b on the latch engages a projection 48 on the link 49, the link is raised, and the adding and printing mechanism is started. If the button 23 is held in depressed position, repeat-operation of the mechanism is prevented by means of a latch 50 which retains the latch 41 until the button is released. The tabulator can be started, without feeding in a sheet, by means of a button 54 in connection with the link 49. Sheet-feed can be started, without starting the tabulator, by depressing a finger-lever 56 having a pin which engages the lug 27 on the link 28. A stop button 58 for the tabulator is connected by linkage 59 to the lever 21. To provide for automatic operation of the mechanism as an incident to total-taking, the link 28 may be connected to the total-shafts.