Patent GB-900295-A (GB)
Title: Improvements relating to sheet handling machines
IPC: B41F21/05
Filed: 1958-01-06
Abstract: 900,295. Printing-machines; feeding sheets. RANGER, A. W. Dec. 11, 1958 [Jan. 6, 1958; Feb. 25, 1958; March 10, 1958], Nos. 410/58, 5993/58 and 7543/58. Classes 100 (1) and 100 (2). A sheet-handling machine, such as a printing- machine, having a lay board to which sheets are delivered individually and successively, comprises in combination a rotatably driven hollow cylinder formed with a longitudinallyextending opening, a rockable first shaft extending longitudinally of the cylinder internally thereof, a second shaft carried by the first shaft, grippers on said second shaft, abutment means adapted to coact with said grippers for transferring a sheet from the lay board to the cylinder and fixed relative to said first shaft to form together with said second shaft and said grippers a rockable unit, control member means disposed externally of the cylinder and coupled to the first rockable shaft, first and second fixed pins adapted to co-operate successively during rotation of the cylinder with said control member means to effect rocking movement of said rockable unit from a first position in which the abutment means are disposed within the cylinder to a second position, angularly spaced from the first position, in which the abutment means project through said longitudinally-extending opening in the cylinder and substantially coincide with the plane of a sheet on the lay board, means operable to effect opening of the grippers at said first position, and means operable to effect closure of the grippers at said second position, whereby at said second position of the rockable unit, the abutment means and the axis of the first shaft are disposed substantially in a radial plane relative to the axis of the cylinder thereby to preclude any substantial radial relative movement between a sheet registered and aligned on the lay board and the abutment means irrespective of the rotational speed of the cylinder. The grippers 9, Fig. 1, are carried on a shaft 7 rotatable on arms 5 fixed to a shaft 4 rotatable in the cylinder end plates, the arms 5 also carrying the gripper abutment bar 8. The grippers are urged to closed position by a helical spring and the shaft 4 is urged clockwise or counterclockwise by a spring 20. When the grippers are in sheet delivery position, a stationary cam 41 engages a roller 48 on a bell-crank lever 42 carrying an abutment 45 which acts on a curved lever 10 on the shaft 7 to open the grippers. At this time, a tumbler 22 slotted at each end and fixed to the shaft 4 is positioned with its inner slot inclined forwards, and as the cylinder rotates counter-clockwise the inner slot is engaged by a fixed pin 23 and the tumbler is moved counter-clockwise to swing the gripper mechanism 7, 8, 9 away from the cooperating cylinder nose. A slot in the lever 10 engages round a pin 13 on the cylinder wall to open and positively control the grippers. A fixed pin 24 then engages the outer slot in the tumbler 22 to rock the shaft 4 clockwise and maintain the gripper mechanism substantially stationary relative to a sheet on a lay board 39 while the grippers are closed under control of the pin 13 and lever 10 and grip the sheet. After the sheet is gripped, front lays carried on a shaft 40a are withdrawn. The spring 20 surrounds a pivoted rod 17 and acts as an overcentre spring to hold the tumbler against stops 25 or 26. The packing clamps 28 are carried on a shaft 29, Figs. 1 and 10, carrying a slotted lever 30 engaging a stud 32 on an arm 33 pivoted on a pin 34 on the cylinder wall. A tommy-bar placed in a hole 35 in the arm 33 is utilized to rock the shaft 29. To lock the clamps open, a recess 36 in the lever 30 engages a roller 37 on a member 38 secured to the shaft 4. By this mechanism, the sheet is correctly registered circumferentially, whatever the speed of the cylinder. In another form, Fig. 12, a tumbler 60 on the rocking shaft 61 carries a roller 63 engaging a fixed cam track 64, pins 65, 66 corresponding to the pins 23, 24. The grippers 71 carried on the shaft 70 are opened by a stationary cam engaging a roller 73 on an arm 72 on one of the grippers. The shafts 70, 61 are spring loaded. The grippers are positively controlled by a stud 76 on the cylinder end wall engaging a slotted lever 75 on one of the grippers. The tumbler 60 is prevented from vibrating during printing by a stop 91 on the cylinder. The last part of the clockwise movement of the shaft 61 is controlled by the cam 64. The packing clamps 81, Fig. 17, are carried on a shaft 82 carrying a bell-crank lever 83 having a recess 85 engaging a stud 86 on a member 87 on the shaft 61 to lock the clamps in open position. If the machine is started with the clamps open, a stationary abutment 88 acts on the lever 83 to close them. In another form, Fig. 18, the gripper unit shaft 61 is rocked by means of a secondary shaft 61a carrying a tumbler 60 through a link 93, levers 92 and pins 94, 95. Specification 507,522 is referred to.