Patent GB-1450173-A (GB)
Title: Machine for treating at least one edge of an envelope to assist subsequent openting thereof
IPC: B43M7/00
Filed: 1973-09-17
Abstract: 1450173 Envelope treating machine KENCO CORP 17 Sept 1973 [15 Sept 1972] 43557/73 Heading B3D [Also in Division F4] A machine for treating an edge of an envelope to assist subsequent opening thereof comprises a plurality of envelope receptacles 18, 19 supported in a circular array, means for rotating the circular array, means 14 for sequentially feeding envelopes to successive receptacles so they pass a first position, means 26 at a second position for treating at least one edge of the envelope as it passes the second position, and means at a third position for discharging the envelope from the receptacle as it passes the third position. The treating of the edges may be effected by cutting, using heat generating means which carbonize and weaken the edge or, as described, by abrading. Three edges of the envelope are abraded to weaken the edges and the envelope is then flexed to break the edges and vacuum means are effective to open the envelope. The machine is disposed within a housing 10 and the envelopes are supplied to the machine from a magazine 13 and feed conveyer 14 and, after opening are discharged on to a conveyer 15 extending between sorting desks 16. The machine has a rotatable wheel 17 which carries a plurality of pairs of fixed and movable paddles 18, 19, the movable paddles having followers 21 engageable by cam lobes on a stationary wheel 20 so that they move against the pressure of springs away from the paddles fixed to the wheel so as to receive and permit positioning of the envelope between the paddles. The envelopes from the feed conveyer 14 are picked up by vacuum means and fed along a track 16<SP>1</SP> to a first positioning floor 24 which has a number of rollers driven so as to urge the envelopes between a pair of paddles opened by a cam lobe, the envelope being positioned by a stop 25 with its radially inner edge projecting a short distance from the inner edge of the paddles. As the wheel rotates, the follower moves from the cam lobe so that the envelope is gripped by the paddles and carried past the first treating means 26 consisting of a convexly-curved grinding wheel which is mounted in an inclined position and grinds the inner edge of the envelope. Thereafter, a cam lobe causes release of the envelope as it passes over a second positioning floor 27 having a plurality of rollers driven to urge the envelope radially outwards into engagement with a stop 28 to position the envelope for grinding of its radially outer edge when gripped by the paddles and carried past a concavelycurved inclined grinding wheel 29. As the wheel 17 rotates further, another cam lobe causes separation of the paddles so that the envelope cam drop on to a flat plate 31 and position the bottom edge of the envelope, the envelope then being again gripped by the paddles and carried over a bottom grinding wheel 30. A rubber gear 32 has teeth spaced to engage the paddles and firmly hold them together during grinding of the bottom edge. After the bottom edge of the envelope is ground, the paddles release the envelope so that it slides over a carrier plate 34 and drops by gravity into a differential separator 35 wherein the envelope passes along a tortuous path so as to be flexed in opposite directions and shear the weakened edges. The opposite panels of the envelope are then acted upon by vacuum means which separate the panels so that the top panel then trails the bottom panel, the envelope and its contents being delivered to the conveyer 15. The grinding wheels are driven through flexible couplings, and each wheel is disposed in a housing connected by pipes to a vacuum chamber for removal of dust.