| 摘要 |
382,613. Typewriters &c. BURROUGHS ADDING MACHINE CO., 2nd Avenue, Detroit, Michigan, U.S.A.-(Assignees of Muller, R. L. ; 14041, Glenwood Avenue, Detroit, Michigan, U.S.A.) July 17, 1931, No. 20527. Convention date, July 23, 1930. [Class 100 (iv).] Sheet-feeding arrangements; paper-supports; paper-shelves.-Means for separating the platen and feed-rollers of a calculating or like machine to form a throat for the front insertion and removal of work-sheets comprises arrangements for retracting the platen to different positions, driving-mechanism normally restrained by a releasable latch which may be controlled by a slight movement of the carriage, and feed-roller releasing devices. In the Burroughs machine shown in Figs. 1 and 2, the platen P is mounted in a frame 21 which is secured to a shaft 22 on the carriage 30, arms 50, 51 on the shaft having pins 49 engaging cam-slots 48 in rocking arms 46, 47 on the carriage. A spring 52 connected to the arm 47 holds the platen in normal position. The platen can be retracted manually by means of a hand-lever 40 which is mounted on the carriage and engages the arm 46, a pin 63 on the arm co-operating with a latch 60 to hold the platen in fully retracted position. The latch is released by means of a fingerlever 65 mounted on the carriage and having a lug 67 for engaging a stud 68 on the latch. The platen is associated with an apron and fingers for guiding a record-sheet, with another apron, a shelf 28, and feed-rollers 32 for guiding work-sheets. The shelf is pivoted on the carriage and drops forwards when the platen is retracted. The feed-rollers are mounted on spring-urged rocking arms 33 on the platen frame, one of the arms having a pin 37 for engaging an abutment 38 on an arm 39 which is pivoted on the carriage and has a pin 71 engaging a cam-slot 70 in a lug 67. When the hand-lever is rocked, the platen is retracted and the feed-rollers are released to permit of front removal and insertion of the work-sheets, the latch 60 holding the platen and feed-rollers in displaced position. On operation of the finger-lever 65, the feedrollers are returned, the latch 60 is released, and the platen is returned to normal position. For automatically operating the platen-retracting mechanism, a rail 80 connecting the arms 46, 47 co-operates with a roller 81 on a pivoted arm 82, Fig. 6, carried by a slide 84, and normally prevented from turning by means of a latch 114. The slide is mounted on a bracket 85 and is coupled by a link 86 to a bell-crank 87 which is connected to an actuating-spring 90 and has a pin 94 for co-operating with a snailcam 93 on a one-revolution driving shaft 14. The bell crank is provided with a dashpot 92. Normally a latch 100 co-operates with a notch 103 to hold the slide 84 in depressed position, the latch having a pivoted one-way abutment 105 arranged in the path of studs 110 on the rail 80. When the carriage is about to be arrested by the tabulating-mechanism, the latch 100 is tripped, the bell-crank 87 raises the slide, the roller 81 lifts the rail 80, and the arms 46, 47 are rocked to retract the platen and effect release of the feed-rollers, thereby permitting insertion of a new worksheet. When the slide has almost completed its stroke, a pin 119 arrests the latch 114, and a spring 112 rocks downwards the arm 82 so that on operation of the thumb-lever 65 the platen is returned immediately to normal position and the feed-rollers are restored. When the starting-bar S is depressed, the slide is returned by means of the snail-cam, the pin 119 causing the arm to re-engage the latch 114. To render operation of the thumblever unnecessary, the studs 110 are replaced by studs 111 arranged at a higher level so that the latch 100 receives only a slight movement and returns immediately to engage a notch 104 in the slide, and the latch 114 is not released. The movements of the slide and rail are thereby reduced, and the platen is only partly retracted and is retained by the roller 81, the latch 60 being ineffective. Means for releasing the feed-rollers when the platen is only partly retracted comprises a slide 167, Fig. 1, resting on a bail 160 forming part of the tabulating-. mechanism. Before retraction of the platen, an adjustable stop 165 co-operates with a stud 163 to raise the bail, and an abutment 168 on the slide is thereby raised into the path of a pin on one of the arms 33. After insertion of a new work-sheet, the machine is started by means of the bar S, and the slide 167 descends to permit automatic return of the feed-rollers and platen, operation of the finger-lever 65 being obviated. A key 140, Fig. 1, for controlling the platen-retracting mechanism independently of the carriage is connected by linkage 142 .. 149 to a latch normally restraining a spring-urged pivoted arm 154. On depression of the key, the arm is released, and a finger 156 thereon engages the abutment 105, the latch 100 being thereby rocked to initiate actuation of the platen-retracting mechanism. The arm is re-engaged with its latch by means of a stud on the slide 84. For controlling the platen-retracting mechanism during movement of the carriage from left to right, the latch 100, Fig. 6, may be replaced by a latch co-operating with a bell crank carrying a pivoted one-way abutment arranged in the path of the studs 110, 111. When the platen is fully retracted, the shelf 28, Fig. 1, rocks a member 170 and thereby prevents operation of the starting-bar S. |
