Patent GB-685022-A (GB)
Title: Envelope patch applying mechanism
IPC: B31B19/00
Filed: 1951-04-02
Abstract: 685,022. Affixing envelope window patches by adhesive. SMITH]] MACHINE CO., Inc., F. L. April 2, 1951. [Aug. 30, 1950] No. 7582/51. Class 73. [Also in Group XVII] In window envelope making machinery including patch applying mechanism which feeds a patch web in from the side, over the envelope blank conveyer, above and across the path of blank travel for severance, and then carries the severed patch in a plane at right angles to the direction of patch web advance for application to the blank (see Group XVII) the patching mechanism, Figs. 1 and 2, comprises a supply reel 30 of patch material 33 which is drawn off the reel by feed rollers 34, 35. A gum container 36 supplies gum through a pick-up roller 37 to transfer discs 38, which apply the gum to the longitudinal margins of the strip 33. Slack take-up rollers 39 are carried at the free end of an arm 40 pivoted at 40a. The web 33 is drawn forward a patch length at a time by a gripper 41 which is carried bv an arm attached to a slide bar 43 which is reciprocated through a link 45 and oscillating arm 44. In the position shown the gripper 41 is near its right hand limit of movement, the movable jaw 46 having been moved to its open position and a clamping finger 47 moved down against a stationary platform 48 to clamp the web 33 for the cutting of a patch by the knife 49. The knife then descends to cut a patch length which is immediately seized by the suction roller 28 and carried forward in a plane at right angles to its previous advance for application to a blank 7, the knife returning to its raised position. When the patch has been moved out of the way the gripper 41 moves to the left to seize the leading end of the web and the clamping finger 47 is then released so that the web may be drawn forward a patch length as the gripper is moved to the right. The gum applied to the side margins of the patch may be sufficient, but in some cases the envelope blank may be provided with patch gum along the margins bordering the ends of the window openings. Figs. 6 and 7 when end to end show partly is section and partly in elevation the construction of the patch. feeding, cutting, and applying mechanism. A shaft 57, which is driven by chain 59 and sprocket 59a and extends through the hollow shaft 58, drives the feeding and gumming rollers of the web 33 through gears 60, 61, sprocket 63 on the shaft 62, and chain 64. A collar 177 is attached to the shaft 57. The chain 64 through a sprocket 65 drives the feed roller 35, and through gears 67, 68, 69a, drives the gum pickup roll 37 which delivers gum from the container 36 to the gumming discs 38 driven through gears 71, 72. A feed roller 34 is mounted on a shaft 75 carried by rocking arms 76 pivoted at 77 and is driven through gears 67, 78, the arms 76 being drawn down by tension springs 79. A rockable arm 80 on a shaft 81 supports the gum container 36 which is spring-loaded to bear against a stop screw 83, the rollers 37, 38, being carried by the container 36. The spring-loaded scraper 85 controls the thickness of the gum film carried by the rollers 38. After leaving the roller 35 the web 33 passes beneath web riding rollers 39 carried by a rocker arm 40 and thence along a stationary guide 91 to the platform 48, in the position shown the leading edge of the web being clamped to the platform by the clamp finger 47. The finger 47 is pivoted at 92 on a block 93 and is operated through arm 94 by a crank 115 on a rock shaft 116. The block 93, Figs. 22 and 23 is formed with a channel 95a in its rear face which fits upon a supporting bar 95, and it is secured by a set screw 98 and plate 96. A spring 100 normally holds the finger 47 against the web 33 on the platform 48. A plunger 103 carrying a knife 49 is slidably mounted in a, vertical channel in the block 93, a compression spring 107 between the plunger and the platform 48 urging the plunger upward. The knife edge is shaped to cut the web progressively from the centre outwards in both directions and the knife is operated through a crank arm 111 on the shaft 112' which cooperates with the top of the plunger 103. Shafts 112 and 116 are rockably supported in a block 120, Fig. 6, and are operated through levers and cams 163 and 165 respectively on the shaft 57. The block 120 is provided with a channel which carries the slidable bar 43 and the block also supports the bar 95. The gripper carrier 42 is provided with a channel which fits upon the rod 43 and its position is adjustable by means of a clamping screw 142, the lower end of the carrier being offset to provide the fixed jaw 144. A coil spring Figs. 19 and 20 (not shown) tends to maintain the movable jaw in its closed position, and a shaft 150, upon which is fixed a bar 152 engageable with a roller 153 carried by the tail portion 149 of the movable jaw, may be rocked to depress the bar 152 to hold the jaw 46 open, or raise the bar to close the jaw. A cam 164 on the shaft 57 operates the rock shaft 150. The reciprocating bar 43 is operated through a link 45 connected to an arm 44 through a pivot block 162a which may be clamped in position, according the the patch length desired, along a slot 162 in the arm 44. A cam 158 on the shaft 62 engages a follower 159 attached to the bar 44. Secured to the shaft 57, which passes through the hollow shaft 58, is an arm 179, Figs. 7 and 28, which has rockingly mounted upon it a bell crank lever 182 one arm of which is formed as a gear segment 183 while the other arm carries a cam follower 184. The gear segment meshes with a gear segment 185 which is fixed to the hollow shaft 58 and the follower 184 co-acts with the cam track 187 of a stationary cam 188. The main part of the track is concentric with the shafts 57, 58, but the portion 191 approaches the centre and causes the segment 185 to be rocked counter-clockwise. In this way the hollow shaft comes to a standstill for an instant, while the severed patch is picked up by the suction patch applier 28, and then picks up speed again. The bed segment 29, Fig. 26, is attached to the hollow shaft 58, and the patch applier 28 is attached to a shaft 196 driven from the shaft 58 through gears 192, 194. The patch carrying segment is fixed to one end of a lever 200 which is pivoted at 201 on a collar 197 attached to the shaft 196. A tension spring 204 forces the other end of the lever 200 against the collar 197 and a stop screw 206 provides an adjustment for the segment. The supply of suction to the segment 203 is controlled through a valve mechanism 214, Fig. 6, which is mounted on the shaft 196. A series of screws 219 support the stationary valve member 221 on the frame 53. The rotary valve member 222 on the shaft 196 controls the suction, which is timed to occur when the segment 203 is in position to pick up a patch, Fig. 26. A suction hose is connected to the nipple 227, and a flexible hose 235 is connected between the nipple 230 and a nipple communicating through the passage 237 with the bore 238 of the segment 203. When the pivot block 162a is adjusted to alter the patch size it is necessary to adjust the rate of feed of the web 33 and the sprockets 63, 65 are therefore made readily replaceable on the shaft 62, 66. Specification 550,690, [Group XVII], is referred to.