Patent GB-1068875-A (GB)
Title: Improvements in box-wrapping apparatus
Inventor: WILLIAMS ALBERT HENRY
IPC: B31B15/00
Filed: 1964-06-10
Abstract: 1,068,875. Making boxes. CALEDEX MACHINE CO. Ltd. June 4, 1965 [June 10, 1964], No. 23966/64. Heading B5D. [Also in Division F2] In a box-wrapping machine of the type in which a box blank and a wrapper on a reciprocating die (13), Fig. 1 (not shown), are forced into the latter by a two-part reciprocating plunger (12a, 12b), the upper member (12a) of the plunger being momentarily halted during its descent into the box when the lower member (12b) reaches the bottom of its travel while wTapping tools (16) (not further described) wipe the margin of the wrapper over the blank, an adjustable linkwork (29, 33) is provided in the drive to the plunger to permit variable selection of the length of stroke of the plunger without altering its lowest position relative to the other parts of the machine. The adjustable linkwork comprises a lever (29) fulcrummed at one end (30) and pivoted by engagement of a follower (31) between its ends with a rotating cam drum (27), the other end of the lever carrying an adjustably-positioned pivot (32), Fig. 2 (not shown), by which it is connected to a lever (33) in turn pivoted at (34) on a reciprocable bar (35) carrying the plunger (12a, 12b). The pivot (32) lies in an arcuate slot 48, Fig. 3, in the lever 29, along which it is slidable and in which it can be adjustably locked by a nut 51 and a washer (52), Fig. 4 (not shown). The pivot comprises an outer flanged sleeve locked in the slot 48, and journalling an inner bush (53), Fig. 5 (not shown). A headed screw (54) extends through the end of the lever (33) and through the rotatable bush (53), and is locked by a nut 55, Fig. 3, having a handle 55a. The washer (52) is in threaded engagement with a shaft (56), Fig. 2 (not shown), carried along the length of the lever (29) and geared through a shaft (63) &c. to a hand-operated ratio control (25) of an expanding-pulley gear (24) transmitting drive from an electric motor (23) to the machine. Having slacked-off the lock nut 51, Fig. 3, the ratio control (25) may be operated so as to adjust the ratio in the speed increasing direction while simultaneously reducing the stroke of the plunger (12a, 12b), and vice versa. The centre of curvature of the arcuate slot 48 when the plunger (12a, 12b) is in its lowest position is centred on the pivot point (37) of the lever (33), thus permitting adjustment of the pivot along the slot without altering the position of the plunger. To adjust the lowest position of the plunger (12a, 12b) relative to the reciprocating die (13), the lever (33) is made of adjustable effective length; the pivot screw (54) extends through a slot (66), Fig. 4 (not shown), lengthwise of the lever (33) and is in threaded engagement with a screw (67) lying therealong and turned by a knob (68). The two-part plunger (12a, 12b) is connected to two sets of plungers (35, 36), the latter carrying the upper member (12a) of the plunger. During descent of the plunger (12), an adjustable cross-piece (37) on the plungers (36) engages a detent (39). The descent of the upper plunger member (12a) is then prevented until the detent (39) is withdrawn by a cam (40) &c. on the cam drum (28). During this pause, the tools (16) wipe the wrapper over the box blank. Alternatively, the upper block (12a) may be temporarily drawn up out of the box after completing its stroke to allow the wiping action. When the plunger (12a, 12b) begins to rise, strippers (43) on a vertically reciprocable cross-head (44) also lowered by the cam (28) &c. engage the box, and the plunger is withdrawn from its inside.