Patent GB-273892-A (GB)
Title: Improvement in machine for turning, folding inward and securing projecting margins of cover paper of covered box shells
IPC: B31B15/00
Filed: 1926-06-26
Abstract: 273,892. Bridgman, H. June 26, 1925. Machines for covering boxes. A machine for turning over, folding in and securing the projecting top margins of covered box shells comprises movable turning and pressing heads carrying inner and outer sets of bars, the inner set of bars turning the margins horizontally as the heads are moved convergently and then turning the margins down vertically inside the shell as the latter is raised between the heads, the outer set of bars being then moved convergently to press and secure the margins in position; the outer pressing-bars are preferably actuated by hydraulic means. When the covers have side margins projecting at the bottom, these may be turned in and secured against the bottom of the box during the above operation. As shown the four movable bar-carrying heads 40 are supported by slides movable in pins 31, 32 mounted on the frame 1 the slides carrying rollers 47 engaging cam channels in a wheel 49 rotatably mounted on a hollow spindle 50 and oscillated thereon by connections from a cam shaft 62. The inner turning-bars 71 are mounted on struts 70 and the outer pressing-bars 80 in brackets 81 carried by the heads and the inner ends of the bars are cut at an angle of 45‹ so that they fit closely together when in their inward positions; the lower corners of the bars 71 are also cut away slightly to provide a clearance which prevents the upstanding cover margins from being pinched between the bars as they converge. The bars are mounted in their supports so as to have free endwise movement so that they automatically adjust themselves as their ends contact and so that they can be easily and quickly changed for different sized box shells. Each bracket 81 is carried by a central plunger 82 and side plungers 83 slidable in a support 85 on the bead, a spring-urged plate 90 on the plunger 82 contacting with a diaphragm 87 clamped between the support and a casing 88 filled with liquid and connected by a pipe 92 to a distributing nozzle 181 of an hydraulic driver casing 164; the casing 164< >is full of liquid and is closed by a diaphragm 163 contacting with a piston 166 carried by a rod 167 actuated by a cam 171 on the shaft 62. The box shells are carried to the heads between guide rails 26 by a belt 16 and are stopped and positioned under the heads by lugs 126 on lifter bars 125 carried by plungers 130 slotted to engage a bar 134 vertically reciprocated from a cam on the shaft 62 and each box shell, before arriving under the heads, is arrested by a finger 190 carried by a rock shaft 192, the finger moving out of the box shell to allow it to be carried under the heads when the preceding box is released by the depression of the lifter bars and carried forward by the belt. When the shell is under the heads the latter are moved by the oscillation of the wheel 49 to carry the bars 71, 80 inwards, the rounded lower edges of the bars 71 turning the projecting top margins of the cover horizontally over the edges of the shell. The lifter bars 125 then move upwards and carry the sides and ends of the box shell into the space between the bars 71, 80, the cover margins being thus turned down inside the box shell by the bars 71. The piston 166 is then actuated by the cam 171 to move the diaphragm 163 and consequently the diaphragms 87 the latter forcing the plates 90 inwards and moving the bars 80 to clamp the sides and ends of the shell between the bars 71, 80 and press the margins securely against the inner surfaces thereof; if the cover has projecting side margins at the bottom these are simultaneously folded under the bottom of the shell and pressed thereagainst by rollers 105 carried by adjustable drums from the brackets 81. The bars 80 are then retracted and the bars 125 lowered, an ejector 110 slidably mounted in the shaft 50 being reciprocated to move the box from between the bars on to the belt 16 and, when free from the lugs 126, the box is carried forward by belts 18; rollers 220 may be arranged above the belts 18 to bear on the top edges of the covered shell and press it against the belts and supporting rails 19 to press and secure the bottom margins in position. The head-carrying arms 31, 32 are carried by rack bars 33 which are moved to adjust the arms to the height of the shell being operated upon by rotating a shaft 35 carrying pinions meshing with the racks. a shell being placed between a projection on the frame and a gauge carried by the arms to determine the extent of movement thereof. The lifting bars and associated parts are laterally adjustable to suit the width of the box being operated upon.