GB1058632A - Improvements in or relating to wrapping machines - Google Patents

Abstract

1,058,632. Wrapping-machines. TAPE ENGINEERING Ltd. July 29, 1963 [Aug. 1, 1962], No. 29521/62. Headings B8C and B8F A wrapping machine includes in combination guide means for feeding the article into a wrapping position, a retractable head controlling the feeding of the wrapping material, driving means for moving the head from an advanced to a withdrawn position, means whereby the web of wrapping material is caused to extend across the feed path when the head is in the withdrawn position so that the movement of the article into the wrapping position causes the web to be wrapped around a portion of its periphery, and means whereby when the article is in the wrapping position the retractable head is moved into its advanced position, so wrapping a further portion of the periphery of the article. In one embodiment, articles in the form of a roll are fed down an inclined ramp having fixed and movable parts B<SP>1</SP>, B respectively and are stopped by a retractable head C with its front wall adjacent the lower end of the ramp, a gauging device D then measuring the diameter of the roll to control the setting of various parts of the machine. The web of wrapping material is fed over the retractable head from a roll H<SP>5</SP> the free end being clamped by a device G beneath the lower end B of the ramp from which a vertical wall B<SP>2</SP> extends downwardly. The vertical wall and a stop member F are positioned by the control device D to be at varying distances from datum lines E, E<SP>1</SP>, Fig. 1, depending on the diameter of the roll to ensure that the top point of the roll is always at a fixed point on the datum line E1. As the head C is withdrawn the web H is stretched across the path of the roll A so that the roll falls against the web and carries it with it into the wrapping position, the movement of the head being so controlled that its front face at its withdrawn position is at a distance equal to the radius of the roll from the line E. Clamp G is automatically released and two folder fingers J engage with the free end of the web and wrap it around the upper portion of the roll. Meanwhile the head C moves to its advanced position wrapping the web of material over the remainder of the upper part of the roll till it overlaps the free edge. The fingers J are withdrawn and a cutting and sealing device housed in the head severs the web and applies adhesive tape along the edges. The sealing may also be effected by applying adhesive to the free edge or if the material is thermoplastic by applying heat to the overlapping edges. The sealing device comprises a reel K<SP>2</SP> of adhesive tape fed forward and clamped by a wedge cam K<SP>3</SP>. An actuating plate K<SP>5</SP> moves forward as soon as the head is in its advanced position and severs the tape against a reaction plate K<SP>8</SP>, the severed portion of the tape being held to the plate K<SP>5</SP> by suction. The plate K<SP>5</SP> moves forward until it engages the roll A and a guillotine K severs the web, after which a pneumatic cylinder K<SP>9</SP> is operated to swing the actuating plate K<SP>5</SP> about its pivot and thus press the adhesive tape firmly into engagement with the overlapping edges of the web. A clamp H<SP>6</SP> is provided to prevent the web from pulling back after it has been severed until the free end is again clamped by the device G, the front of the head having a re-entrant portion C<SP>6</SP> into which the ramp projects to enable the web to be picked up by the clamping device. The amount of web gripped in the clamping device may be controlled by feeding back some of the web after severance by means of a take-up roller over which it passes. Means may be provided to adjust the tension of the web and to keep the web in close contact with the front of the head, Fig. 4, not shown. Also in an alternative construction the head may be withdrawn vertically or in an arcuate path in lieu of horizontally, Fig. 6 (not shown). In another embodiment, Fig. 8 (not shown), the apparatus is arranged for packaging rectangularly shaped articles, the retractable head moving in a direction parallel to the ramp and normally occupying a withdrawn position. The article is fed on to a platform R across which the web is stretched, its free end being held by a clamp S and which is then lowered into a wrapping position. The clamp S then moves towards the article thus bringing the free end of web to lie on its upper face. The wrapping head now advances to the right as shown to fold the web over the upper face of the article and overlap the free end. The wrapping is then completed as in the first embodiment. In one modification (Fig. 9, not shown) the end of the web is folded on to the article's upper face by moving the package laterally beneath the supply ramp and in a further modification (Fig. 10, not shown) the ramp feeds the article straight to the wrapping position and then the ramp rises above and over the article taking the free end of the web with it.