Patent GB-749151-A (GB)
Title: Envelope patch applier
IPC: B31B19/00
Filed: 1954-02-25
Abstract: 749,151. Machines for applying transparent patches to windowed envelopes. SMITHE MACHINE CO., Inc., F. L. Feb. 25, 1954 [Dec. 21, 1953], No. 5581/54. Class 73 In a machine for applying transparent patches to window openings of envelope blanks, rollers 5, 6, 7 Fig. 1 or endless feed belts 130, 131 Fig. 21 feed envelope blanks 3 at a uniform speed over a bed roller 11 and rollers 47, 48, 49 Fig. 1 draw patch web 40 from a reel 41 and feed it to a suction drum 50 at a speed less than that of the blanks 3, the drum 50 rotating at a surface speed equal to that of the blanks so that a slip drag is exerted on the web 40. A cutter comprising a knife 72 set into and rotatable with the drum 50 and a stationary knife 74 cuts a patch from the leading end of the web 40 during each rotation of the drum 50 which patch is then carried by the drum and transferred by suction control means to a rotary suction patch applying segment 12 which rotates at the speed of the blanks and applies the patch to a blank 3 while it passes over the bed roller 11. A gumming mechanism (not shown) gums the marginal area around the window opening of each blank 3 as it approaches the roller 11. To ensure that the stationary knife 74 Fig. 3 does not form an obstruction to the passage of the freshly cut web 40, a web pressing blade 120 is mounted on a spring-urged rocking arm 123 carrying. a follower roller 124 which engages a generally, circular cam 125 on the shaft 67 of the drum 50. A shallow, recess 127 in the cam 125 permits the blade 120 to press the web 40 against the upper face of the cutting blade 72 and as the latter recedes, the web 40 is kept clear of the stationary blade 74. The applying segment 12 has suction passages in its forward margin which communicate through a rubber tube 39 to the interior of the hollow shaft 16 of the segment 12, and valve means ensure that suction is applied when the segment 12 comes opposite the leading end of a patch on the drum 50 and maintained until the leading end is carried into engagement with a blank. The knives 72, 74 Fig. 5 are much longer than the drum 50 which can be adjusted axially of its shaft 67 relative to the knives in accordance with the position of the window opening in the blank and provision is also made for adjustment of the drum circumferentially of its shaft in order that one row or another of suction openings 87 provided all over the surface of the drum is timed to underlie the forward margin of a patch at the moment of severance regardless of its length. Stationary and rotary valve discs 91, 93 and a cam-operated clapper valve 89a Fig. 1 control two independent suction, sources and the drum 50 is divided into a patch conveying and transfering segment immediately following the knife 72 and slip drag segments: the arrangement is such that one source of suction controlled by the clapper valve 89a is constantly in communication with the conveying and transfer segment except during the period of transfer to the applying segment 12 Whilst the other source of suction controlled by the disc valves 91, 93 is in communication with the slip drag segments as they travel in the web contacting range of movement and is cut off at other times. In order to provide for the adjustment of the drum 50 along its shaft telescopic connections are provided between the drum 50 and the rotary valve disc 93. The segment 12 is similarly adjusted along its shaft 16. The belt feed arrangement for the blanks shown in Fig. 21 is designed for blanks which are unusually short and narrow, the blanks being fed between twin belts 130 and twin belts 131 engaging at opposite ends of the window opening. The belts 130, 131 are independently latterally adjustable. Specification 460,185 [Group XVII] is referred to.