Apparatus and method for applying a tubular member over an article

Abstract: An apparatus for applying a tubular member over an article includes means (3) for feeding a continuous web of a flattened tubular material, means (4) for cutting an individual tubular member (1) from the web, a first belt conveyor unit (5) for conveying the tubular member (1) fed from the cutting means (4), a second belt conveyor unit (10) for conveying the tubular member (1) in such a manner as to open up at least a leading end of the tubular member (1) as the tubular member (1) is continuously conveyed, a mandrel (20) for receiving the tubular member (1) from the opened up leading end of the tubular member (1), and a means (24) for slinding the tubular member (1) along a peripheral surface of the mandrel (20) so that the tubular member (1) is entirely opened up. A distance (L2) between a point (A) where the cutting means (4) cuts the tubular member (1) from the web of the tubular material and a point (B) where the first belt conveyor unit (5) starts to convey the tubular member (1) is greater than the length (L3) of the individual tubular member (1).

Description: FIELD OF THE INVENTION This invention relates to an apparatus and method for opening a flattened tubular member, for example, a cap seal and a label, and automatically and successively applying the tubular member over a predetermined portion of an article, for example, a bottle and the like. BACKGROUND OF THE INVENTION There has been disclosed the apparatus of this type, for example, in Japanese Patent Application Laid-open No. 63-29 (see also EP 0 269 753 A), which includes a feed roller for feeding a continuous web of a flattened tubular material towards a mandrel and applied over the same for opening the flattened tubular material, a cutting unit disposed between the feed roller and the mandrel for cutting an individual tubular member from the web, and a rotary member abutting against the tubular member on the mandrel for pulling down the tubular material towards a lower portion of the mandrel via its rotational movement. In accordance with the above arrangement, because of the need to stop the feeding operation of the tubular material during cutting operation, the feed roller can not successively feed the tubular material to the cutting unit. This generally limits the speed at which the tubular member can be applied over an article. The apparatus of this arrangement requires the steps of applying the tubular material over the mandrel from above, cutting the individual tubular member from the tubular material by the cutting unit, and pulling down the same by the rotary member. Accordingly, if the tubular material is successively fed, it is likely that the rotary member pulls the tubular material which is still in a continuous form. This may cause untimely feeding of the tubular member, and poor application of the same over the article. It is an object of the present invention to provide an apparatus and method for applying the tubular members over the article at high speed, while securing timely and rapid feeding operation, even if the tubular material is successively fed. SUMMARY OF THE INVENTION In accordance with the above object, the apparatus of the present invention includes means for feeding a continuous web of a flattened tubular material, means for cutting an individual tubular member from the web, a first belt conveyor unit below the cutting means for longitudinally conveying the tubular member fed downwards from the cutting means, a second belt conveyor unit for longitudinally conveying the tubular member in such a manner as to open up at least a leading end of the tubular member as the tubular member is continuously conveyed, a mandrel for receiving the tubular member from its opened up leading end, and a means for sliding the tubular member along a peripheral surface of the mandrel so that the tubular member is entirely opened up. A distance between a point where the cutting means cuts the continuous web of the tubular material into the tubular member and a point where the first belt conveyor unit starts to convey the tubular member is greater than the length of the tubular member. In accordance with this arrangement, since the distance between the point where the cutting means cuts the tubular member from the web and the point where the first belt conveyor unit starts to convey the tubular member is greater than the length of the individual tubular member, it is unlikely that the first belt conveyor unit unintentionally pulls down the tubular member which is not completely cut from the web. After the tubular members are cut from the web, they fall down onto the first belt conveyor unit, and conveyed to the second belt conveyor unit at predetermined pitch. Since the second belt conveyor unit also opens up the individual tubular members and applies the same over the mandrel at the same pitch as that of the first belt conveyor unit, the tubular members can timely be conveyed throughout the operation. The second belt conveyor unit may comprise a pair of suction belt members having a vacuum port and disposed lateral sides of the path of the tubular members so that the tubular members pass therebetween. In this arrangement, the apparatus further includes a vacuum chamber associated with the suction belt members so that the tubular members are sucked by the suction belt members. The suction belt members each has a width smaller than that of the flattened tubular member so that at least one of parallel fold lines thereof protrudes sidewards from the suction belt members. At least one twisting means is disposed at a lateral side of the suction belt members for twisting the at least one of the parallel fold lines of the tubular member. The twisting of the fold line of the tubular member causes a relative slippage between opposed flat side portions of the tubular member, and consequently causes these side portions to be separated from one another. This twisting operation facilitates the second belt conveyor unit to equally open up the tubular member, and smoothly apply the same over the mandrel. The present invention also provides a method of applying a tubular member over an article, as defined in appended claim 3. The above, and other objects, features and advantages of the present invention will become apparent from the detailed description thereof read in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic front elevation illustrating one embodiment of the present invention. FIG. 2 is a front elevation of an essential portion of FIG. 1. FIG. 3 is a side elevation of the essential portion of FIG. 2. FIG. 4A is a front elevation illustrating a portion that a twisting plate twists a tubular member. FIG. 4B is a cross sectional plan view of the portion of FIG. 4B. FIG. 5A is a cross sectional plan view illustrating the film in open state. FIG. 5B is a cross sectional plan view illustrating a comparative example. FIG. 6 is a cross sectional front elevation illustrating a tubular member positioning mechanism. FIG. 7 is an elevational view illustrating an essential portion of the positioning mechanism of FIG. 6. FIG. 8A is a bottom plan view with a partial cross section of the positioning mechanism. FIG. 8B is a fragmental perspective view of the portion of FIG. 8A. FIGS. 9A, 9B and 9C are front elevations with partial cross section illustrating consecutive steps of applying the tubular member over a bottle. FIG. 10 is a schematic top plan view illustrating various stations including the apparatus of the present invention, through which the tubular member is securely applied over the article. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a continuous web of a tubular material made of a thin and soft plastic film is flattened along its longitudinal axis, and rolled around supply roll 2. A pair of feed rollers 3 are driven to successively feed the web material from the supply roll 2 via a guide roller 17. A cutting unit 4 includes a stationary blade 4a and a rotary blade 4b, and is disposed below the feed rollers 3 to cut individual tubular members 1 from the web material. A sensor is disposed above the guide roller 17 in order to detect a predetermined marking point printed on the web material 1, and transmit a signal to a control unit (not shown), which controls the cutting unit 4 and the feed rollers 3 to operate in association with each other. A first belt conveyor unit 5 includes two pairs of endless belt members 6, which are respectively disposed lateral sides of the path of the tubular members 1 in order to hold each tubular member 1 from its both longitudinal sides. Each pair of the endless belt members 6 are wound around the opposite end portions of each of small guide pulleys 7a, 7b, 7c and 7d, and a large drive pulley 9, as illustrated in FIG. 3. The guide pulleys 7a, 7b, 7c and 7d guide the endless belt members 6, and the drive pully 9 disposed at the lowermost portion of the first belt conveyor unit 5 rotates the endless belt members 6 so that the endless belt members 6 of the opposite lateral sides of the path of the tubular members 1 are spaced apart from each other to define a clearance L1 at the opposit first guide pulleys 7a, brought into a close relationship to the opposite endless belt members 6 at the second guide pulleys 7b, and move straightforward to continuously press the tubular members 1 and convey the same downwards. A distance L2 between a first point A where the cutting unit 4 cuts the web and a second point where the rotation axes of the second guide rollers 7b are met is set to become greater than the length L3 of the individual tubular member 1. The first belt conveyor unit 5 starts to convey the individual tubular member 1 at the second point. The second pulleys 7b are movable in the upper and lower directions along the path of the tubular members 1 so that the distance L2 between the first point A and the second point B is easily adjustable. The drive pulleys 9 are controlled to rotate the belt members 6 at a predetermined speed in the directions of the arrows of FIG. 2. A second belt conveyor unit 10 includes a pair of suction belt members 11 with a plurality of vacuum ports 11a defined along en entire length thereof, a plurality of large guide rollers 12a and small guide rollers 12b, and a pair of vacuum chambers 13 which are respectively disposed inside of each suction belt member 11 to be associated with the vacuum ports 11a of the suction belt members 11. Each suction belt member 11 is wound around the respective drive pulley 9, and the pulleys 12a and 12b, in such a manner as to be rotated substantially at the same speed as that of the endless belt members 6. As being apparent from FIG. 3, the suction belt member 11 passes between the opposite belt members 6 when winding around the respective drive pulley 9 Referring to FIGS. 4A and 4B, a width W of each suction belt member 11 is smaller than a width W1 between the parallel fold lines 1a and 1b of the flattened tubular member 1 so that, when the tubular member 1 passes through the suction belt members 11, the parallel fold lines protrude sidewards of the vacuum chambers 13. The vacuum chambers 13 extend downwards in a close relationship to one another in its upstream side, but gradually move away from one another as they advance in its downstream side. A pair of upper twisting plates 14a and a pair of lower twisting plates 14b are disposed lateral sides of the vacuum chambers 13 11 in different heights. Each of the twisting plates 14a and 14b has a sloping edge 15, and is disposed so that, once the tubular member 1 reaches the sloping edge 15, the respective protruding portion of the tubular member 1 slides along the sloping edge 15 and consequently twisted in one direction, as best shown in FIG. 4A. Each sloping edge 15 faces opposite direction to those of the same and opposite lateral sides of the vacuum chambers 13. With this arrangement, the opposite protruding portions of the tubular member 1 are respectively twisted in the opposite directions to one another via the upper twisting plates 14a, and then oppositely twisted via the lower twisting plates 14b, as the suction belt members 11 convey the tubular member 1 downwards. A mandrel 20 has a pointed top end which faces between the lower ends of the suction belt members 11, and a cylindrical body with a diameter which becomes larger as it advances downwards. A plurality of small rollers 21 and 22 are disposed inside of the mandrel 20 and slightly protrude from respective openings (not shown) defined by a peripheral wall of the mandrel 20. A conveyor unit 24, having a pair of endless belt members 26 which are driven via a plurality of pulleys 25, are disposed at the lateral sides of the mandrel 20 in such a manner as to clamp and hold the mandrel 20 throughout the entire length thereof. Each endless belt member 26 defines a clearance to the mandrel 20 at its upper portion. The pulleys 25 disposed along a middle portion of each endless belt member 26 are disposed slightly inside of the rollers 21 of the mandrel 20, thereby loosely suspending the mandrel 20 in position via a hooking relationship between the pulleys 25 and the adjacent rollers 21. A conveyor unit 29 is disposed below the mandrel 20 to successively feed the bottle 30 at predetermined pitch to the apparatus 28 of the present invention. Referring to FIGS. 6 and 10, a tubular member positioning mechanism 32 includes a rotary table 33 which is supported by a rotation axis 32a, and a plurality of pressure units 36, and is disposed at the downstream side of the apparatus 28. The pressure units 36 each includes a cam follower 40 which follows a cam groove 39 of a cam plate 35 mounted on the rotation axis 32a, and a pressure body 41 which is movably mounted on a pair of guide bars 38 which are, in turn, vertically mounted on the rotation axis 32a. A plurality of support bars 44 extend downwards from the pressure body 41, and terminated by a circular plate 45 with an opening 45a at its center, through which a pressure bar 46 extends downwards. The pressure bar 46 is movably mounted on the pressure body 41, and urged downwards by a weight 48 mounted on its upper end. Referring to FIGS. 7, 8 and 8A, a plurality of pressure arms 50 are pivotably mounted on the lower surface of the circular plate 45 via bolts 51 in such a manner as to horizontally swing around its base portion. A horizontal protrusion 53 protrudes from a side of each pressure arm 50 at a right angle in the same direction as those of the other pressure arms 50. A rubber ring 54 is wound around the base portions and the horizontal protrusions 53 of the pressure arms 50 so as to bias the pressure arms 50 radially and inwardly of the opening 45a. Stoppers 55 are disposed with predetermined spacing on the circular plate 45 to limit the inward movement of the respective pressure arms 50. The diameter D of the opening 45a of the circular plate 45 is larger than the diameter of a target portion of the bottle 30, around which the tubular member 1 is applied. A heating unit 58 is disposed at the downstream side of the positioning mechanism 32 to heat the tubular member 1 applied over the bottle 30, as illustrated in FIG. 10. The operational steps of applying the tubular member 1 over the bottle 30 will be described hereinbelow. The continuous web of the tubular material is set to a roll feeder 60, and continuously drawn downwards from the roll by rotation of the feed rollers 33. The cutting unit 4 is operated in association with the feed rollers 33 and cut the individual tubular members 1 from the web. Since the leading ends of the tubular members 1 do not contact the endless belt members 6 during the cutting operation, the tubular member 1 is not unintentionally pulled downwards by the endless belt members 6, and therefore correctly cut from the web of the tubular material. The individual tubular members 1 drop from the cutting unit 4, clamped by the endless belt members 6 and fed to the second belt conveyor unit 10. During the conveyance by the first belt conveyor unit 5, the tubular member 1 can be conveyed straightforwards and securely fed to the suction belt members 11, since it is continuously clamped via its opposite longitudinal edges by the endless belt members 6. The tubular member 1 is conveyed by the second belt conveyor unit 10 at the same speed as that of the first belt conveyor unit 5, thereby attaining the smooth and timely conveyance of the tubular members 1 throughout the units 5 and 10. The suction belt members 11 suck the opposed flattened sides of the tubular members 1 by the operation of the vacuum chambers 13, and convey the tubular members 1 to the downstream side of the apparatus 28. Once the tubular member 1 with the opposite longitudinal edge portions protruding sidewards from the vacuum chambers 13, reaches the upper twisting plates 14a, the tubular member 1 is twisted via the sloping edges 15. The tubular member 1 is then oppositely twisted via the sloping edges 15 of the lower twisting plates 14b. With this arrangement, even if the opposed flattened side portions of the tubular member 1 are stuck to one another, the twisting motions enable those side portions to be forcibly slipped sidewards and separated from one another. Thus, sticking force between the opposed flattened side portions of the tubular member 1 can be weakened. The tubular member 1 is then conveyed towards the lower portion of the second belt conveyor unit 10, where the tubular member 1 is forcibly opened up from its leading end, as the opposed flattened side portions thereof are sucked and conveyed by the respective suction belt members 11. Since the sticking force between the opposed side portions has been weakened via the twisting operation performed by the twisting plates 14a and 14b, this opening up operation is easily done, even if the opposed flattened side portions again stick to one another. In case that the twisting plates 14a and 14b are omitted from this embodiment, a sticking portion remains near the opposite fold lines 1a and 1b of the tubular member 1 during the opening operation, as illustrated in FIG. 5B. This may cause poor application of the tubular member 1 over the mandrel 20. The tubular member 1 applied over the mandrel 20 is pulled downwards by rotation of the endless belt members 26 of the conveyor unit 24. The endless belt members 26 convey the tubular members 1 at a speed four times faster than that of the suction belt members 11 of the second belt conveyor unit 10 to promptly pull the tubular members 1 downwards. The tubular member 1 is gradually opened up from its leading end as it slides along the mandrel 20, and is entirely opened up from its leading end to rear end at the lowermost portion of the mandrel 20. During the pulleys 25 of the conveyor unit 24 are rotated, the corresponding pulleys 22 idle so that the mandrel 20 can continuously be suspended in position. The tubular member 1 then drops from the mandrel 20 onto the top of the oncoming bottle 30 which is conveyed under the apparatus 28 by the conveyor unit 29 operated in synchronism with the conveyor unit 24. The parallel fold lines 1a and 1b of the tubular member 1 still remain, after the tubular member 1 is applied over the bottle 30, and therefore causes the tubular member 1 to come back to a flattened state. Subsequently the tubular member 1 stays around an upper portion of the bottle 30. The bottles 30 with the tubular members 1 thereon are successively conveyed to the positioning mechanism 32 via the conveyor unit unit 29, and mounted on the oncoming pressure units 36 of the turntable 33. During the bottles 30 turn around the rotation axis 32a via the turntable 33, the pressure body 41 in each pressure unit 36 lowers along the guide bars 38 via cam operation of the cam groove 39 and the cam follower 40 so that a lower end 46a of the pressure bar 46 is introduced into a bottle top 30a of the bottle 30, and fix the bottle 30 in position. Along with the rotation of the rotation axis 32a, the pressure body 41 further lowers so that the bottle top 30a of the bottle 30 is introduced into the opening 45a of the circular plate 45. As lowering the pressure body 41, the pressure arms 50 abut against the bottle 30, and swing radially and outwardly, as they slide along a periphery of the bottle 30, forcing against tension force effected by the rubber ring 54. If a ring member 57 is employed in the pressure unit 36 to solely lower the tubular member 1, the tubular member 1 is likely to be slipped sidewards and insufficiently applied over the bottle 30, as illustrated in FIG. 9C. On the contrary, the pressure arms 50 of this embodiment swing radially and outwardly as sliding along the periphery of the bottle 30 so that the tubular member 1 is equally pressed, and lowered to predetermined portion of the bottle 30, as illustrated in FIGS. 9A and 9B. After positioning the tubular member 1 to the targeted portion of the bottle 30, the pressure body 41 is elevated so that the circular plate 45 is moved away from the bottle top 30a of the bottle 30. The bottle 30 is then removed from the turntable 33 and mounted on the conveyor unit 29 to be conveyed to a pre-heater 61, in which the tubular member 1 is shrunk via heat in such a manner as to be temporarily fixed in position. The bottle 30 is then conveyed to a heater 63, in which the tubular member 1 is completely shrunk, resulting in tight contact with the bottle 30. In this embodiment, the steps of receiving the cut tubular member 1 and opening the tubular member 1 are performed by the first and second belt conveyor units 5 and 10, and the suction belt members 11 of the second belt conveyor unit 10 are provided with the vacuum ports 11a which are associated with the vacuum chambers 13. Accordingly, it is possible to employ the suction belt member 11 of a thick and rigid type, and the endless belt members 6 of a thin and easily bendable material of a low cost. Instead of the endless belt members 26 of the conveyor unit 24, rollers may be employed to pull down the tubular member 1 along the mandrel 1. A specific arrangement of this is not limited to the above embodiment. In addition, the tubular member 1 may be varied in material and dimension. The article on which the tubular member 1 is applied is not limited to the bottle 30. Containers of other types or other articles become targets for the present invention. The cutting unit 4 may include a pair of blades which are horizontally moved towards one another and cut the tubular material in cooperation with one another.

Claims: An apparatus for applying a tubular member over an article comprising means (3) for feeding a continuous web of a flattened tubular material, means (4) for cutting an individual tubular member (1) from the web, a first belt conveyor unit (5) below the cutting means (4) for longitudinally conveying the tubular member (1) fed downwards from said cutting means (4), a second belt conveyor unit (10) for longitudinally conveying the tubular member (1) in such a manner as to open up at least a leading end of the tubular member (1) as the tubular member (1) is continuously conveyed, a mandrel (20) for receiving the tubular member (1) from the opened up leading end of the tubular member (1), and a means (24) for sliding the tubular member (1) along a peripheral surface of said mandrel (20) so that the tubular member (1) is entirely opened up, wherein a distance (L2) between a point (A) where said cutting means (4) cuts the tubular member (1) from the web of the tubular material and a point (B) where said first belt conveyor unit (5) starts to convey the tubular member (1) is greater than the length (L3) of the individual tubular member. The apparatus as set forth in claim 1, wherein said second belt conveyor unit (10) comprises a pair of suction belt members (11) with a vacuum port (11a) and disposed lateral sides of the path of the tubular member (1) so that the tubular member (1) passes therebetween, and a vacuum chamber (13) associated with said suction belt members (11) so that the tubular member (1) is sucked by said suction belt members (11), said suction belt members (11) each having a width (W) smaller than a width (W1) of the flattened tubular member so that at least one of parallel fold lines (1a, 1b) thereof protrudes sidewards from said suction belt members (11), and at least one twisting means (14a) disposed at a lateral side of said suction belt members (13) for twisting said at least one of the parallel fold lines (1a, 1b) of the tubular member (1), as the tubular member (1) is conveyed. A method of applying a tubular member over an article comprising feeding a continuous web of a flattened tubular material, cutting an individual tubular member (1) from the web by a cutting means (4), longitudinally conveying the tubular member (1) fed downwards from said cutting means (4) by a first belt conveyor unit (5) arranged below the cutting means (4), positioning said cutting means (4) and said first belt conveyor unit (5) so that a distance (L2) between a point (A) where the cutting means (4) cuts the tubular member (1) from the web and a point (B) where the first belt conveyor unit (5) starts to convey the tubular member (1) is greater than the length (L3) of the tubular member (1), opening at least a leading end of the tubular member (1) as longitudinally conveying the same by a second belt conveyor unit (10), sliding the tubular member (1) from the opened up leading end thereof over a peripheral surface of a mandrel (20), so that the tubular member (1) is entirely opened up, and applying the tubular member (1) over the article.

Inventors: NAGANO SATOSHI, NAGANO, SATOSHI
Applicants: FUJI SEAL INC, FUJI SEAL, INC.
Application year: 1996
Main classification: B65C3
IPC codes: B67B5, B65C3