Patent GB-269639-A (GB)
Title: Improvements in or relating to machines for folding the edge of leather or like material
IPC: B42C7/00
Filed: 1926-01-16
Abstract: 269,639. British United Shoe Machinery Co., Ltd., (United Shoe Machinery Corporation). Jan. 16, 1926. Bookbinding-machines.-A machine for folding the margins of leather &c. coverings upon the cardboard or like, covers of books, pocket-cases, &c. is provided with separate mechanisms for folding rounded and square corners and has straight edge-folding mechanism for folding the portions ot the margins between the corners. The corner-folding mechanisms are adapted to be operated to fold the corners successively, and the mechanism for folding rounded corners is provided with a plaiting tool to facilitate the folding. Small book covers having rounded corners may be folded completely by the rounded corner folding-mechanism alone. The mechanism for folding the margins of the rounded corners has a triangular work table 15, Figs. 2 and 3, with an apex corresponding to the curvature of the corner, and two side walls 17 connected by a rounded corner piece and forming edge guides adjacent to the edges of the table 15. The table 15 is mounted on a spring-pressed plunger and normally held level with the upper edges of the walls 17. Two corner guides 43 at the ends of pivoted arms are adapted to bear upon the two side adjacent to the corner of the work in the operative position, the guides being lifted automatically to enable the work to be pushed beneath them. Mounted in a bracket 23 at the end of an arm 59 pivotally mounted above the table 15 is a forming plate 21, Fig. 2, of similar shape to the table, so that when the arm 59 is lowered the table is depressed and the margin bent up into the path of a reciprocating folder 19 of the shape shown in Fig. 6, the work being clamped between the members 15, 21. The folder 19 cooperates with a plaiting tool 25 which is slidably mounted above the plate 21 in a block 28 and is pressed forward by a spring 35. As the folder 19 advances, the corner clamps 43 are automatically lifted out of its path and the folder gathers the upstanding margin about the plaiting tool 25, after which an abutment on a reciprocating slide 135 carrying the folder engages the plaiting tool, whereupon the plaiting tool and folder move together and exert a pull on the margin which they drag between them. In this way the margin is folded over the edge of the plate 21, after which the table 15 is automatically lowered to release the pressure, the plate 21 is slidably withdrawn from the turned-over margin, and the table 15 is lifted again to press the margin against the underside of the folder 19. The operative face of the plaiting tool 25 is substantially of U-section to co-operate with the chamfered edge of the folder, a screwed rod 39 which adjusts the position of the plaiting tool being set to leave sufficient clearance for the margin to be dragged over. The recess 20, Fig. 6 at the junction of the angular faces of the folder facilitates the gathering of the margin over the nose of the plaiting tool. The four rounded corners having been folded, the cover is laid upon a work table 61 at the front of the machine and pushed beneath resilient fingers 69 upon the front edge of the straight edge-folder 65, the object of the fingers being to impart a preliminary bend to the straight margin. In operation the folder 65, Fig. 2 and 3, advances to fold the margin over the stiff backing, the work table rises to press the fold and then moves down, after which the folder is withdrawn. The other straight edges of the cover are subsequently acted upon similarly. The work table 61 is secured on a bracket 71, Fig. 2, which is adjustably mounted on a casting 75 supporting the table 15 of the rounded corner folding mechanism. Spring buffer members 87 within recesses at each end of the casting bear upon a transverse plate 89 engaging the end of a lever 93 which is operated by a cam 99 to produce simultaneous movement of the work tables 15, 61. The cam shaft 101 is preferably controlled by a treadle of the toe-and-heel type arranged so that on depressing the heel a vertical rod 105 is elevated and turns a lever 121 to lift the corner guides 43 for the work to be inserted, and on depressing the toe the folding &c. mechanisms are actuated by cams on the shaft 101. The slide 135 on which the corner folder 19 is mounted is connected to the folder 65 of the straight-edge feeding-mechanism by a pin 149, so that the two fclders move in unison and act simultaneously on two different covers. The underside of the slide 135 is slotted to engage the end of a camoperated rocking lever 141. The bracket 23 currying the forming plate 21 and plaiting tool 25 is adjustably mounted at the end of a rod 155 which is slidablv mounted on the arm 59 and at its rear end carries a roller 167 guided within an arcuate cam track 169 formed at the upper end of a cam-operated rocking lever 171. The rear end of the arm 59 is forked to form hubs which are pivoted between screws 183, 185, one hub having secured to it a lever 187 engaging a cam 189 to effect the raising and lowering of the arm 59, the movement of the lever 187 also producing a longitudinal movement of the rod 155 to withdraw the plate 21 from the turned-over margin. In folding the margins of book covers having square corners the straight-edge folder 65 is used in conjunction with mechanisms disposed at the side edges of the table 61. The cover 500, Fig. 5, and stiff backing 400 are placed on the work table 61 with a side margin 700 overhanging one edge of the table, and the two are pushed rearwardly so that the spring fingers 69 turn over the top margin, the folder 65 being then moved forward to draw the margin over, after which the table rises to press the margin against the folder. The end portion of the turned-over margin overlapping the edge of the table is then pressed by a fold presser consisting of a flat face on an extension 225 on the shaft of a pinion 233 which is rotated into operative position by a segmental rack 235, Fig. 3, on a rocking arm 237. The left-hand margin is next pressed in a similler manner by the mechanism at the left hand edge of the work table, after which the cover is turned through 180‹ to operate upon the opposite margin. The straight edges are folded by presenting them in succession to the straight edge folding- mechanism.