Patent GB-476780-A (GB)
Title: Improvements in and relating to article wrapping machines
IPC: F02M55/00
Filed: 1937-01-12
Abstract: 476,780. Wrapping - machines. AMERICAN MACHINE & FOUNDRY CO. Jan. 12, 1937, No. 911. Convention date, Oct. 1, 1936. [Class 94 (i)] In a wrapping-machine in which wrapping material is drawn from a web to enfold the article, after which a wrapper length is severed from the web, the tightness of the wrapping is controlled by engagement of the web by a rotatable member adapted to be intermittently driven, the period of operation being capable of variation. A machine is diametrically shown in Fig. 3, in which an article A is fed on to an inclined pivoted lifting table 55, being partially wrapped in a web W during this movement, and further application of the wrapper takes place during the rise of the table to the position shown' in broken lines. The web is draped over the left-hand side of the article by a rod 56<1> and the article is advanced on to a table 57 by a pusher, the web being severed by a knife 58 and ledger plate 62. When the table is in the upper position a roller 54 mounted thereon presses the trailing end of the web against a feed roller 19, Figs. 1 and 3, adapted to be driven in either direction or to be left free to control the tightness of the wrapping. The roller 19 is supported in bearings 50 on an oscillating frame 51, and is swung into and out of contact with the roller 54 by a cam-operated lever 53. The pusher - carrying chain 10 engages a sprocket 11, Figs. 1 and 2, on which is mounted a gear 20. A train of gears 21, 27, pawl 24, ratchet 25, and gears 28, 29, rotates the sprocket 11 and transmits the drive through a chain 17 and sprocket 18 to the roller 19. The gear 28 also meshes with a gear 28a mounted on a stud 30 on a quadrant 31 pivoted on the shaft 26 so that the drive on the roller 19 can be reversed by disengaging the gears 28, 29 and engaging the gears 28a, 29. This is done by engaging a manipulating knob 37 on the quadrant in one of two positions defined by grooves 34, 35 on the cover plate 13a engaged by a projection 36. In order to vary the duration of the drive imparted, the pawl 24 carries a stud 40 engaged by a cam disc 42 adapted to be moved into various positions of adjustment by an arm 45 and a knob 47. An indicating scale 2 ... 6 is marked on the cover plate. In order to obtain the greatest degree of loose wrapping, the knob 47 is turned to position 6, and this moves the high portion 42a of the cam 42 into the lowermost position and allows the pawl 24 to engage the ratchet 25 at the earliest point in each rotation of the gear 21. The web is then fed to form a loop W<1>, Fig. 1, to allow a loose wrapping to take place, the excess wrapper being wiped underneath the article during passage on to the table 57. In order to obtain lesser degrees of looseness, the knob 47 is moved in an anticlockwise direction to cause the engagement of the pawl at a later stage. The same operations produce varying degrees of tightness when the gears 28a, 29 are engaged by operating the knob 37. A neutral position may be arranged in which the roller will not be driven, and a moderately wrapped packet will be produced. Specification 431,505 is referred to.