Patent GB-636959-A (GB)
Title: Process for the formation of sealing devices and for the application thereof on articles
IPC: B21D51/34
Filed: 1947-07-24
Abstract: 636,959. Seals and sealing. STOFFEL, F. L. July 24, 1947, No. 19981. [Class 146 (ii)] For shaping and applying sealing devices on to articles, cups or recesses are moved stepwise through three working positions on a continuous path, at which positions, simultaneously, firstly a small plate or blank is placed in an empty cup, secondly, a blank in a cup is formed into a sealing device and thirdly a shaped sealing device in a cup is fixed on to an article placed thereover, the emptied cup then being carried back to the first working position. A rotatably mounted flat-topped horizontal table 3 has on its lower side six pins 5 arranged on a circle at equal distances from each other and similarly arranged, has six notches 10 and six cylindrical insets 6 with cups 7 of depth equal to the thickness of a blank 1 and a central hole 8 of diameter equal to that of the finished seal, the insets providing the three working positions A, B and C. The table 3 is rotated by means of a reciprocating slide 14, which may be operated from a foot-pedal, with a bearing eye 15 rotatably carrying a driver 16 under the action of a spring 17 and with an abutment surface 18 abutting one of the pins 5, forward movement of the slide 14 a distance carrying the pin over the corresponding arc of the circle. The rotation is then stopped by a spring pressed pawl 12 falling into the next notch 10, the driver 16 being pressed towards the slide 14, on its return movement, by the pin 5 behind abutting its inclined surface till it is passed the pin. Above the position A is a magazine 2 (Fig. 8) for the blanks 1 of star cross section, mounted in a clamping holder 24, pivoted at 25 on a fixed support 21 and under the action of a spring 27, the magazine being clamped by a handwheel 26 and easily exchangeable. An extension piece 22 of the magazine remains always in the holder 24 level with the table 3 but can be tilted with the holder in case of jamming of the lowermost blank. At the position B, a stamp or plunger above the table forces the blank from the cup 7 into the hole 8 raising the prongs to the position shown in Fig. 11. At the position C, an article G to be sealed is placed over the cup and a plunger 28 from underneath forces the prongs of the seal through the article G and a plunger from above bends the prongs inwardly by means of an annular shaped recess, the two plungers above positions B and C being coupled together and operated in a single lever. In a modification of the final sealing operation, Fig. 11, two part seals are used, the plunger 32 above the position C being provided with springs 34 in a recess to hold a sealing ring 33 which is introduced manually on a ladle 30, the prongs of the seal being bent inwardly by the plunger 32 and anchored in the sealing ring 33. A modification of the two part sealing device is described in which the sealing ring is introduced into the upper plunger automatically, a sealing ring being taken from the bottom of a magazine by a recessed slide to a position under the upper plunger, the sealing ring being removed from the recess by a spring gripping device housed in the plunger and reciprocated to grip the ring internally and raise it into the plunger. The article G to be sealed is placed over a support between the table and upper plunger which has a central bore through which the lower plunger 28 passes with the pronged seal. The sealing rings are secured in the magazine by means of a vertical rod with a nut at one end fitting into a recess under the slide where it is removed, the rod then being taken out and reinserted after a distancing sleeve has been introduced above the magazine, the tip of the rod then being clear of the slide.