Patent GB-690580-A (GB)
Title: Machine for making packings closed by a cover
IPC: B65B65/02
Filed: 1950-11-02
Abstract: 690,580. Making packing containers. EBAUCHES SOC. ANON. Nov. 2, 1950 [Nov. 4, 1949], No. 26814/50. Classes 83 (ii) and 83 (iv). [Also in Groups VIII, XVI, XVII, XXIV and XXVI] A machine for making metal packing containers closed by a cover comprises a central drive operatively connected by a fluid coupling with a rotary packaging table, with means for feeding material for the containers and for the covers and with a press comprising tools for securing the covers to the containers. Strip feed mechanism.-Strip aluminium for the container bodies 1 and paper or carton for the covers 2, Fig. 44, are fed from rolls 4 and 5, Fig. 1, which are rotated intermittently by a friction drive from motors 8, 9 respectively under the control of switches 10, 11 operated by arms 12 in contact with supply loops 6, 7 of the aluminium and paper. The unwound strips are drawn through punching devices a, b by roller feeds c, d, driven intermittently by a motor 121 under the control of a switch 15 operated by a loop of punched strip 14. The roller feed devices c and d each comprise a spring-pressed idle roll 67, Fig. 4, co-operating with a roll 59 driven by a pawl 62 and ratchet 60 from a lever 50 rocked from the motor 12<SP>1</SP>. After punching, the strips pass over the rolls 4 and 5 and are fed by reciprocating grippers e to a rotary table 18 beneath a press f, all of which are driven by a motor 19. Between the roller feeds c and the press f the strips pass along straight guides 71, 72, respectively, Fig. 17. Above the guides is a rod 73 mounted in guides 72a and reciprocated by an eccentric block 74. One end of the rod carries an adjustable feed finger 76 adapted to engage a punched hole 42, Fig. 12, and so feed the aluminium strip forward on a movement to the right. At the completion of the feed stroke another finger engages the strip recesses 43 to prevent a backward feed on the movement of the rod to the left, during which a finger 80 on the other end engages and feeds the paper strip, a fixed but adjustable finger 87 serving to prevent any back feed of the strip. Punching.-Each of the punching devices a and b comprises a block 34, Fig. 4, mounted on the machine frame and carrying a die 35 which co-operates with a punch 40 on a carrier 38 guided for reciprocatory movement by columns 37 passing through sleeves in the block 34 and joined at their ends by a cross-head 46 coupled by a screw 48 to a lever 50 pivoted at 49 and rocked through connecting-rods 52 and 69, respectively, from an eccentric 53 driven by the motor 121. A pin 54 is adjustable along a radial slot for varying the stroke of the punch. The punched aluminium and paper strips have the forms shown in Figs. 12 and 15, respectively. Rotary die and work carrier.-The revolving table comprises a plate 18, Fig. 21, with eight dies, mounted above but spaced from a gear 102. Four stop-pins 112 project downwardly from the plate and five stop-pins 113 project upwardly from the gear and are displaced at angles of 45 degrees from the pins 112. The table is driven from the motor 19 through a fluid coupling which allows it to be stopped at will. Projecting between the table 18 and gear 102 and mounted on an axially movable pin 269 is a bit 268, Fig. 24, of such a width that it lies in the path of the pins 112 or 113 and so stops the table. An eccentrically adjusted arm 273 at the lower end of the pin 269 allows the position of the bit to be set so that when the table is stopped, the dies are accurately positioned with respect to the tools in the press head. Movement of the bit between its upper and lower positions to allow a partial rotation of the table is effected by a lever 280 on a shaft 278 carrying a gear 277 meshing with a rack on the pin 269. In order to prevent the lever 280 being operated so as to permit constant rotation of the table, the shaft 278 actuates through a lostmotion pin-and-slot connection, a cam 282 which depresses a rod 285 which moves a spring- pressed lever out of a slot in a safety pin 294 which is then driven by an arm of a spring- operated lever 298 into a depression in the pin 269. The other arm of the lever 298 carries a pin engaging in a slot 304 in a rod 305 connected with the cross-head of the press so that when the press has performed a working stroke, the upper end of the slot 304 moves the lever 298 to withdraw and reset the safety pin, thus permitting a further movement of the table control lever 280. Fluid coupling.-The fluid coupling comprises a central gear 130, Fig. 18, keyed to a shaft 126 and housed within a casing 136 in which are mounted three planet gears 139, the whole casing being immersed in an oil bath 138. Extending upwardly from the casing 136 is a sleeve 132 carrying a sprocket 131 driven by chains from the motor 19. To the upper end of the shaft 126 is keyed a sleeve 123 formed at its upper end as a disc carrying the eccentric block 74 and formed at its lower end as a gear 127 meshing with a gear 128 which in turn meshes with the gear 102 of the table 18. If the table is locked, the pressure of oil developed between the gears 139 and 130 is released by means of passages 141 normally closed by spring- operated balls 142. If, however, the table is free, it is driven through the fluid coupling, one revolution of the gear 127 turning the table through the angle between adjacent dies of the table. Press actuating mechanism.-The press head 166 is operated by vertical columns 167, Fig. 33, connected by a cross-head 169 engaged by a crank-arm 170 driven by an eccentric on a shaft 172 on which is mounted a fly-wheel 24 driven by a belt from the motor 19. The shaft may be engaged with the fly-wheel by means of a clutch, Figs. 28-31, comprising a pin 177 housed in a groove in the shaft and tending to be rotated by a spring 181 so as to engage a notch 180 in a sleeve 179 keyed to the fly-wheel. Rotation of the pin is normally prevented by a cam disc 185 loosely mounted on the shaft and tending to be rotated by a spring 187 anchored to a cam disc 184 keyed to the shaft. Discs 184 and 185 may be prevented from rotating by a stop slide 192. When the table 18 has been rotated to bring a die into operative position the resulting movement of a rod 161 (see below) causes the stop 192 to be raised. Disc 185 then turns until an inner cut-out 188 reaches the position of the pin 177 which then rotates to couple the shaft and fly-wheel. When the cam 186 of the disc 185 reaches the again lowered stop 192, the relative rotation of shaft and disc effects a rotation of the pin 177 and the disengagement of the shaft which is brought to rest by the cam disc 184 abutting the stop 192. The movement of the rod 161 is effected as follows. The gear 127 of the fluid coupling also drives through gears 150 and 151, an outer sleeve to which is secured the lower end of a torsion spring 153, the upper end being secured to an inner sleeve 164 rotatable within the outer sleeve but normally held by a stop 163, Fig. 20, engaging a lever 148. When a die is in position, the other end 147 of the lever moves into a notch 145 in the sleeve 123, thus releasing the sleeve 164, a cam on which lifts a follower 156 to depress the rod 161. Dies.-Each die comprises a block 104 with depending stem 205 slidable in bores in the plate 18 and gear 102, respectively, and normally held in an upper position by a spring 207. Beneath the dies positioned at stations 1 and 7 are stops 210 preventing downward movement. Shearing; cupping; seaming.-The press head contains three tools coaxial with the dies at stations 1, 5 and 7 respectively. The end of the aluminium strip in guide 71 is fed over the die at station 1 and is there acted upon by the tool shown in Fig. 34, comprising a drawing punch 211 and holding ring 212, one edge of which co-operates with the end of the guide 71 to cut off the blank from the strip. The holding ring also acts as a stripper. Four guide pins depending from the tool engage the punchedout holes 42 and recesses 44 of the strip and thus serve to position the blank as well as the tool. The bottom of the punch may emboss the bottom of the container. The end of the paper strip in guide 72 is fed over the cupped container at station 5 and beneath the tool shown in Fig. 35, which co-operates with the end of the guide to shear off the cover. The tool also forms an upstanding cylindrical lip around and extending above the cover, the die yielding against the spring 207. At station 7 this lip is pressed down firmly on to the cover by the tool shown in Figs. 36 and 37 and comprising a sleeve 229 moving with the press head and having rollers 236 at its lower end and a block 237 slidable within the sleeve and normally urged downwards by a spring 241. A rod 239 passing through the block and secured to it by a pin 240, carries at its upper end a nut 244 bearing on the top of the sleeve and at its lower end is bored to receive a holding-down plate 251. Pivoted on the block are arms 246 urged outwardly by a resilient pad 247 and having at their lower ends jaws 248 with conical outer surfaces bearing on the rollers 236. As the tool descends, the jaws are prevented from moving down by an apertured plate 256 and are pressed inwardly by the rollers, this movement of the jaws bending the container lip inwardly, as shown in Fig. 36. As soon as the jaws are compressed to the size of the aperture 257, the spring 241 drives them forward to press the lips firmly down over the cover. Each of the tools has a spring such as the spring 233 which yields in the event of an overload due to an incorrect positioning of the dies. Beneath the table 18 is an air compressing cylinder 119, Fig. 33, whose piston 264 is operated from the shaft 172. On every stroke of the press, air is compressed and driven into a cap 120 above the table and escapes through a member 267 which directs it to the last station to eject the seamed container. Goods to be sealed in the containers are