5860. Funk, N. E. March 7. Envelopes, making.- Relates to a machine for forming envelopes from a continuous strip of paper, and consists more particularly in forming an envelope with a window opening covered by transparent paper, the transparent paper extending right across the blank and having its ends sealed beneath the folded flaps. The web of paper, after being drawn from the roll, hangs in a loop and is carried over a segmental guide 28, Fig. 11, and between bars 31, which are carried in a pivoted frame adapted to be clamped in any desired position. The bars and the guide keep the paper taut and smooth out all wrinkles. The paper next passes between one or more platen printing-presses 222, then over an horizontal supporting-plate 34 while the ink is drying, and then to a feed-roller 36 and the first device for gumming the blank. The presses print on the web a band of colour in the position to be occupied by the transparent paper patch. The feed-rolls and the gummers are intermittently rotated by a rackbar 44, which is secured to the reciprocating frame of the printing-presses 222, through the medium of a ratchet mechanism. In order to hold the web taut as the presses rise, it is engaged by a roller 37 pivoted to an horizontal slide 38, which is moved inwards by a cam 40 also secured to the frame of the presses. The gumming-mechanism consists of two wheels or rolls which are mounted on a shaft 52, Fig. 19, and apply gum to the sealing-flap and to that part of the blank that is to be covered by the transparent patch. As it is desirable to use different qualities of gum for these purposes, the gum-transferring rolls rotate in different compartments of the gum-box 51. The gumming-rolls press the web against the feed-roll 36 and are driven by the roll. After being gummed, the web passes beneath a reciprocating die 62, which cuts out the window aperture from the blank. A strip 11 of transparent paper, drawn off from a roll mounted in standards 71 by mechanism similar to that already described, is pressed into contact with the web as it passes between the feed-rollers 80, 81. The web next passes beneath the mechanism shown in Figs. 30 and 34, which cuts superfluous paper from the web to form the blanks and applies gum to the part of the web connecting adjacent blanks. The mechanism consists of a vertically reciprocating head 92 which carries on its underside cutting-dies 92<a>, 92<b> for shaping the blanks, punches 95, 96 for punching the holes 10<a>, 10<h> respectively, and a gum-pad 97. This pad receives gum from a roller 109 mounted on an horizontally reciprocating slide 108, which in turn receives gum from rolls 102, 103, 104 dipping in a gum-trough 100. The part 10<c> of the blank is then folded over on to the body by means of a plate 119, Figs. 36 and 40, which reciprocates both vertically and horizontally, and by means of a plate 116 which is pivoted at one end 117 and is forced by a spring 118 to bear with its other end against the blank along the line in which the. fold is to take place. The plate 119 first lifts the part 10<c> of the blank into a vertical position, as shown in dotted lines in Fig. 40, and then, moving horizontally, folds it over the plate 116. The plate 119 then moves away, and a pressing-plate 125, Fig. 36, is swung around through a right-angle by a shaft 124 into position above the crease in the blank and is then moved downwards to press the crease. The plate 125 remains in position while the blank is drawn forward, thus firmly creasing it. The blank is next drawn forward by feed-rollers 140<a>, 141<a>, Fig. 45, to the mechanism for folding the gummed flaps. These rollers have part of their periphery cut away in order to avoid making contact with the gummed parts of the blank. Previous to being folded, the blank is severed from the web by a moving blade 150 and a fixed blade 151, which cuts the web along the gummed part between the adjacent blanks. The folding-mechanism, shown in side elevation in Fig. 45 and in end elevation in Fig. 47, is situated over an opening in the table 161 within which a trap 162 reciprocates, the upper surface of the trap being normally flush with the surface of the table. Arranged above the trap is a plunger which consists of horizontal plates 176 carried at the lower end of a rod 171. These plates are movable horizontally and are normally drawn together by springs, but are separated periodically by an oscillating cam 177 secured to a sleeve 178 surrounding the rod 171. The blank, after being cut off from the web by the blade 150, is clamped between the plates 176 and the trap 162 and is carried by them downwards through the opening in the table. The gummed flaps of the blank are bent upwards by stationary folders 183, 183<a> and are then folded over on to the body of the blank by semicylindrical rotating rollers 184, the plates 176 having been drawn out of the way of these folders by springs and the cam 177. The closing-flap of the envelope is then folded down on to the body part by a folder 190, Fig. 47, carried by the plunger. This folder 190, in addition to sharing the vertical motion of the plunger, is movable both horizontally and vertically with respect to the plunger. When the plunger has reached its lowest point and the side flaps of the envelope have been folded, the folder continues to move downwards and then moves inwards horizontally, thus folding the closing-flap of the envelope over the bevelled edge 162<a> of the trap 162, as shown in Figs. 80 and 81. After the folders 184, 190 have returned to the normal positions, the plunger and trap move downwards through a little distance and separate slightly. The envelope is then knocked off the trap by pins 200 which project upward from an horizontally reciprocating bar 201 and slide into slots in the trap. The envelope falls in between a roller 210 and feed-belts 212 and is fed by them into a trough 215. During the formation of the blank, two holes 10<g>, 10<h>, Fig. 34, were punched in it. When the envelope is sealed, the gum on the closing-flap seals through the hole 10<g> on to the enclosed letter, thus preventing it from moving relatively to the aperture. The aperture 10<h> is intended for the insertion of a knife or pointed instrument to facilitate opening. Similar apertures may he punched in the transparent paper, before it is stuck to the web, in positions that will coincide with the gummed flaps of the envelopes. These apertures return a quantity of gum and assist in securely attaching the end flaps to the body. All the various folding, gumming, and feeding devices are constructed as units that are readily detachable from the machine frame. The transparent paper may also be omitted, and the aperture left uncovered, or, further, the apparatus for cutting out the window aperture may be omitted, the envelope being formed with a closed address-bearing portion.