Patent GB-634050-A (GB)
Title: Improvements in or relating to method and apparatus for making paper containers
IPC: B31B17/00
Filed: 1948-03-19
Abstract: 634,050. Paper bags &c. LILY-TULIP CUP CORPORATION. March 19, 1948 No. 8219. Convention date, April 2, 1947. [Class 94(ii)] An apparatus for making two-piece receptacles, such as paper cups, comprises an intermittently moving turret table 42; female dies at stations I-VIII and coacting male dies which shape the circular side wall of the cup and attach a beaded bottom to each. Thermoplastic adhesive is used for the seams, and the material is preferably given an overall heat resistant coating. The blanks are successively punched from a vertically-disposed web. Heating means, as by steam, is used in the female dies in zones corresponding to the adhesive seams, the temperature being controlled, to prevent delamination of the joints. Driving means for the various shafts and cam gears are mounted on a main drive shaft 64. Station I. The blanks are punched from a web W, Fig. 7, by.a punch 98 on laterallysliding rods 113, having a rubber faced extension 115. The web is supplied from a roll through ratchet gear and a drum D provided with pins d which engage marginal holes in the web W. As the punch die 98 moves forward to pass the punched blank through an aperture 97, the web is clamped between a member 109 and the inner face of the die plate 80. The die 98 is stopped after passing through the web, but the parts 114, 115 carry the blank into a folding shell 140, the blank is curved around so that the end of the blank carrying the adhesive strip falls behind a tucker finger 147, Fig. 11 (not shown) as the pusher 114 is withdrawn rearwardly and a spider 150 pushes the blank downwardly along the tapering sides of the shell 140 into a die F. Each of the dies F is provided with a steam jacket 53 disposed near the adhesive seams of the cup to soften the adhesive so that under pressure, the body is formed. Inlet and outlet steam pipes 55, 57 are provided. Station II. Here the prefolded body blank is placed in axial register with a cooperating male die which presses into the body. A cooling medium is circulated through the male die. Station III. A separately-formed flanged cup bottom is punched from a strip S, Fig. 3 and the bottom is transferred by a holder 220 (Fig. 1) over the cup body at station III, the flange extending downwards. The lower marginal edge of the body is then folded over the flange, the bottom being held by suction. The folding die 246, Fig. 19 (not shown) is rotated by a pulley driven by a belt 272, Fig. 1 driven from a pulley 273 on a shaft 274 of an electric motor 275. Station IV. Here the bottom half of the cup is held firmly by a downwardly-moving male die, and a bottom-rolling mechanism moves upwards to iron the two parts of the cup into intimate contact. The ironing roller 280, Fig. 21 (not shown) is given an eccentric movement at the top of its upward movement, and caused to roll around the cup bottom. Station V. The cup is axially aligned with a shaped male die which moves downwards, an expandable plug is moved upwards into the cup bottom and then to press the parts together. The expanding plug 320, Fig. 24 (not shown) comprises a number of segments resiliently held together by a spring and moved outwards when engaged by an expander head. Cooling fluid is circulated through the male die. Station VI. This may repeat the function of station V or may be an ineffective or dwell station. Station VII. The cup, complete except for the rolling of the rim, is withdrawn here and moved horizontally to station VIIA. The ejecting mechanism, Fig. 26, comprises a stem 346 which is moved upwards by a lever 352, acting through a spring 358, the lever being actuated by a cam 357 on the shaft 64. When the stem moves upwards a plunger 365 is contacted by a screw 366 and a valve 364 opened to admit compressed air to a bore 360. The air passes through outlets 362 to eject the cup from the die F. The beader mandrel 370, Fig. 1 on a shaft 371 is rotated step-by-step through Geneva mechanism. Each of the three arms of the turret 370 carries a beading die. The cup is held in position on a head 397 (Fig. 27 not shown). The completed cup is then discharged, at Station VIIB, by compressed air, controlled by a valve head 437, Fig 3, being delivered into the cup. The cup passes on to wire rails 444 which guide it to stacking rails and the lip of the cup is then engaged by a stacking pusher to move the cup into stacking engagement with cups previously discharged. Station VIII. This is an idle station and the empty female die is moved on to Station I again.