GB878353A - Improvements in or relating to gripper mechanisms for presses - Google Patents

Abstract

878,353. Feeding and delivering sheets. CROSLAND Ltd., WILLIAM. Aug. 18, 1959 [Aug. 30, 1958], No. 27896/58. Class 100(1) Gripper mechanism for presses such as cutting, creasing and embossing presses comprises a bar capable of being attached to chains or belts in the press, the bar having a plurality of spikes thereon which are pressed into a sheet, e.g. of heavy board, thereby to grip the sheet and enable the latter to be passed through the press. Gripper mechanism. A series of bars 10 is mounted between chains 11 which carry the bars through the press. The trailing edge of each bar is rabbeted and recessed at 13 (Fig. 17, not shown) to form projecting portions 12. The portions 12 are provided with downwards projecting spikes 14 which may be curved or barbed. The bar 10 is positioned above the feed level of the sheets and the sheets are impaled upon the spikes by means of a bar 15 which presses the sheets upwards when they are positioned below the bars 10. The bar 15 is mounted on a U-shaped frame 16 and has a sliding connection with front lays 20 by means of bolts 19 passing through vertical slots in the bar. The front lays 20 arrest a sheet as it is fed into position for impaling on the spikes 14 and are mounted on brackets 22 for angular adjustment about a pivot point 21. Brackets 36 on each arm 20 are slotted to receive and guide the base of the frame 16. Vertical reciprocation of the bar 15 is effected by two cams 37 mounted on a driven shaft 38. An arm 40 at each side of the press is oscillated by the corresponding cam 37, the oscillation being transmitted by a rod 42 to a lever 44 secured to a shaft 49; the rod 42 is slidable in an eyelet 43 on the lever 44, the eyelet being normally held in engagement with a collar 42 on the rod by a spring 46. Also secured to the shaft 49 are two levers 50 which have a peg and slot connection with the frame 16 at 52. As the arms 40 oscillate so the bar 15 is reciprocated. Faulty feed detectors; sheet registering. The bar 15 is recessed at 15a to accommodate a portion of the front face 60 of each of two feelers 59 which are pivoted at 21 and are urged by a spring 61 into engagement with the recesses, the faces 60 in this position being slightly in front of the front lays 20. When a sheet is fed up to the front lays 20, as in Fig. 7, if it is correctly registered it presses back the feelers 59 until the faces 60 are level with the faces of the lays so that the bar 15 can be moved upwards. If the sheet is incorrectly registered and fails to bear on one or both of the feelers the bar 15 is prevented from rising by the engagement of at least one feeler in its recess 15a. Although the bar 15 does not rise the arms 40 are moved upwards by their cams and compress the springs 46 whereby a toggle arrangement 54, 55, 56 is caused to actuate a switch 53 which stops the machine. In a modification Fig. 16 the bars 10 are mounted so as to be capable of slight lateral and longitudinal movement in relation to the chains 11 and are registered before a sheet is affixed to the spikes 14 (the right-hand station Fig. 16) and before the sheet is operated on in the press. Vertically movable stops 76 (Fig. 17, not shown) of triangular cross-section are reciprocated by the movable platen of the press and engage in V-shaped recesses in the leading edges of the bars 10 as the latter are moved up to the stops. Delivery apparatus. After being impaled on the spikes 14 a sheet is carried through the press by the bar 10 and is stripped off the bar 10 by a stripper bar 68, Figs. 10, 11, which is shaped on one edge so as to correspond with the recessed edge of the bar 10. The bar 68 is carried by arms 67 secured to a shaft 66 which is oscillated by means of a cam 63 and lever 64. Guides 71 prevent undue flexing of the bar 10 at the stations where the sheet is affixed to it and stripped from it.