Method and device for applying adhesive tape to cylindrical bodies

Abstract

The invention relates to a device for applying adhesive tape (40) to the cylindrical surface (21) of a cylindrical body (20), said device comprising: at least two axially parallel securing rolls (30a, 30b) designed to make contact with the cylindrical surface of the cylindrical body; an adhesive tape feed for feeding the adhesive tape (40) to the cylindrical body (20); and means for rotating the cylindrical body (20) about its cylindrical axis.

Claims

1. A method for applying adhesive tape to a cylindrical surface of a cylindrical body, comprising: (a) positioning the cylindrical body on at least one conveyor belt; (b) contacting the cylindrical surface of the cylindrical body with respective lateral surfaces of at least two axially parallel securing rolls; (c) moving the cylindrical body away from the at least one conveyor belt by displacing the at least two securing rolls relative to the at least one conveyer belt and/or displacing the at least one conveyer belt relative to the at least two securing rolls; (d) applying the adhesive tape to the cylindrical surface of the cylindrical body; and (e) winding the adhesive tape onto the cylindrical body by rotating the cylindrical body about a cylindrical axis of the cylindrical body.

2. The method according to claim 1, wherein at least one of the securing rolls serves as guide roll for the adhesive tape, wherein the adhesive tape is passed around the guide roll in a section corresponding to a central angle from about 1? to about 270?.

3. The method according to claim 2, wherein the guide roll catches the adhesive tape by suction.

4. The method according to claim 2, wherein the adhesive tape is passed around the guide roll in a section corresponding to a central angle from about 45? to about 210?.

5. The method according to claim 2, wherein the adhesive tape is passed around the guide roll in a section corresponding to a central angle from about 90? to about 180?.

6. The method according to claim 1, wherein, in step (c), the at least one conveyor belt is movable away from the cylindrical body.

7. The method according to claim 1, further comprising at least partially cutting-through the adhesive tape with a cutting blade, a water cutting device, or a laser cutting device.

8. The method according to claim 1, further comprisingbefore the contacting step and/or after the winding stepdisplacing the cylindrical body along roll axes of the securing rolls or along the cylindrical axis of the cylindrical body via the at least one conveyor belt.

9. The method according to claim 1, further comprising positioning the cylindrical body relative to an adhesive tape feed.

10. The method according to claim 9, wherein the cylindrical body is positioned relative to the adhesive tape feed by contact elements.

11. The method according to claim 1, wherein contact with the cylindrical surface of the cylindrical body is made by at least three axially parallel securing rolls, which are disposed around a cylindrical circumference of the cylindrical body in such a way that the at least three securing rolls pinch the cylindrical body therebetween.

Description

(1) FIGS. 1A to 1F are schematic sectional views of an embodiment of the invention, which illustrate the device and method for applying adhesive tape to a cylindrical surface of a cylindrical body.

(2) FIG. 2 is a schematic sectional view of a further embodiment of the invention, in which the cylindrical body lies on the guide roll under its own weight.

(3) FIG. 3 is a schematic sectional view of a further embodiment of the invention, in which the liner of the adhesive tape is detached from the adhesive tape and wound up, after the adhesive tape has been passed round the guide roller.

(4) FIG. 1A shows a schematic sectional view of a device 10 for applying adhesive tape 40 to a cylindrical surface 21 of a cylindrical body 20. The device 10 comprises securing rolls 30, one of which is embodied in the form of a guide roll 30c. The guide roll 30c has a vacuum zone 32, in which the adhesive tape 40 is held on guide roll 30c by means of a vacuum. The adhesive tape 40 is provided as adhesive tape web from a roll of adhesive tape 45. In the shown embodiment this is a double-sided adhesive tape, one adhesive surface of which is covered by a covering or a liner 41. In the process the adhesive tape 40 is unwound from the roll of adhesive tape 45 in such a way that the liner 41 is in a position between the adhesive tape 40 and the lateral surface of the guide roll 30c. A sectioning facility 50 is provided, to cut the adhesive tape into individual strips of adhesive tape.

(5) In FIG. 1A the cylindrical body 20 lies on conveyor belts 61 of a insertion mechanism 60. With the help of the conveyor belts 61 or of the insertion mechanism 60 the cylindrical body 20 can be displaced along its cylindrical axis, until it is in a sticking position within the shown device 10, i.e. a position, in which the adhesive tape 40 can be stuck onto the cylindrical surface 21 of the cylindrical body 20. Therefore in a first step of an embodiment of the method for applying the adhesive tape 40 to the cylindrical surface 21 of the cylindrical body 20 the cylindrical body 20 is first placed outside the drawing plane of FIG. 1A onto the conveyor belts 61 of the insertion mechanism 60 and transported into the drawing plane of FIG. 1A with the help of the conveyor belts 61. When the sticking position is reached, the forward movement of the conveyor belts 61 stops and the phase in which the cylindrical body 20 is secured by means of the securing rolls 30 begins. For this purpose the bottom two securing rolls 30a, 30b are moved orthogonally to the extent of their roll axes and symmetrically to each other towards the cylindrical axis of the cylindrical body 20.

(6) After a certain time the securing rolls 30a, 30b make contact with the cylindrical surface 21 of the cylindrical body 20 with their respective lateral surfaces and begin to raise this cylindrical body from the conveyor belts 61 of the insertion mechanism 60, as shown in FIG. 1B. The securing rolls 30a, 30b are moved towards the cylindrical axis of the cylindrical body 20 until the cylindrical body 20 is raised completely from the conveyor belts 61 of the insertion mechanism 60 and makes contact with the lateral surface of guide roll 30c. Means to record the pressure (not shown) ensure that the movement of the securing rolls 30a, 30b is interrupted, as soon as the desired pressure of one or more securing rolls 30a, 30b on the cylindrical surface 21 of the cylindrical body 20 has reached a desired value.

(7) In the next step, illustrated in FIG. 1C, the adhesive tape 40 is applied to the cylindrical surface 21 of the cylindrical body 20. For this, in the embodiment that is shown, one of the securing rolls 30a, 30b is set into anticlockwise rotation around its roll axis by means of a drive (not shown). The friction that exists between the lateral surface of the driven securing roll 30a/30b and the cylindrical surface 21 of the cylindrical body 20 leads to clockwise rotation of the cylindrical body 20 around its cylindrical axis. The rotation of the cylindrical body 20 is transferred in turn to the guide roll 30c, which rotates accordingly anticlockwise and unwinds the adhesive tape 40 from the roll of adhesive tape 45 and feeds it to the cylindrical surface 21 of the cylindrical body 20.

(8) As mentioned already, the side of the adhesive tape 40 facing away from the lateral surface of the guide roll 30c is exposed and sticky. Therefore as soon as the adhesive tape 40 is fed to the cylindrical surface 21 of the cylindrical body 20 owing to the rotation of the guide roll 30c, it begins to stick to the cylindrical surface 21 of the cylindrical body 20. Continued rotation of the cylindrical body 20 and of the guide roll 30c leads to the adhesive tape 40 being wound gradually onto the cylindrical surface 21 of the cylindrical body 20. The desired adhesion of the adhesive tape 40 to the cylindrical surface 21 of the cylindrical body 20 is provided by the pressure that the guide roll 30c exerts with its lateral surface on the cylindrical surface 21 of the cylindrical body 20.

(9) Before the cylindrical body 20 has performed a complete rotation about its cylindrical axis, the drive of the securing roll 30a/30b is interrupted and the adhesive tape 40, together with liner 41, is cut through by means of the sectioning facility 50, as illustrated in FIG. 1D. This process takes place, when the length of the adhesive tape 40 already wound on the cylindrical body 20 together with the length of the not yet wound adhesive tape 40 that is between the cylindrical body 20 and the sectioning facility 50 equals the cylindrical circumference of the cylindrical body 20. As a result of this the length of the cut-off strip of adhesive tape is equal to the cylindrical circumference of the cylindrical body 20 and can consequently cover this in exactly one layer.

(10) After the adhesive tape 40 has been cut to length by the sectioning facility 50, the drive of the securing roll 30a/30b is reactivated, so the cylindrical body 20 continues to rotate and the remaining section of the strip of adhesive tape is stuck onto the cylindrical surface 21 of the cylindrical body 20, as shown in FIG. 1E. When this process has been completed, the stuck-on strip of adhesive tape surrounds the cylindrical surface 21 of the cylindrical body 20 in one layerwithout any overlapping and ideally without any significant gap between the abutting edges of the strip of adhesive tape.

(11) Any adhesion of the subsequent adhesive tape 40 that is fed to the already covered cylindrical surface 21 of the cylindrical body 20 by means of the guide roll 30c is prevented by the adhesive strip on the cylindrical surface 21 of the cylindrical body 20 still carrying the already mentioned liner 41 on its outward-facing surface.

(12) After the entire cylindrical surface 21 of the cylindrical body 20 has been covered with adhesive tape, the drive of the securing roll 30a/30b is again interrupted and the cylindrical body 20 is again deposited on the conveyor belts 61 of the insertion mechanism 60, as shown in FIG. 1F. For this the securing rolls 30a, 30b again move, orthogonally to their roll axes and symmetrically to each other, diagonally downwards into their initial position. The cylindrical body 20, to which adhesive tape has been stuck, is finally moved out of the sticking position by means of the conveyor belts 61, which now serve as ejection mechanism. In the embodiment shown this is done by further transportation of the cylindrical body 21, to which adhesive tape has been stuck, into the drawing plane, where it is handed over to a packing and removal unit (not shown).

(13) FIG. 2 shows a further embodiment of the device 10, comprising a cylindrical body 20, securing rolls 30, one of which serves as guide roll 30c, adhesive tape 40 and a sectioning facility 50. The adhesive tape 40 is again provided as double-sided adhesive tape, one surface of whichthe downward-facing surface in the example shownis covered with a liner 41.

(14) In the embodiment shown the cylindrical body 20 lies on the guide roll 30c under its own weight. This has the advantage that the maximum pressure is provided on the contact area between the lateral surface of the guide roll 30c and the cylindrical surface 21 of the cylindrical body 20. In addition, in this embodiment, if the own weight of the cylindrical body 20 allows it, the provision of only two securing rolls 30, one of which forms the guide roll 30c, might suffice.

(15) In this embodiment the cylindrical body 20 is again fed to the sticking position by means of conveyor belts 61 of a insertion mechanism 60. Then the insertion mechanism 60 is moved downwards from the cylindrical body 20, so the cylindrical body 20 is deposited on the securing roll 30a and the guide roll 30c. A drive of the securing roll 30a around its roll axis sets the cylindrical body 20 into rotation about its cylindrical axis, which in turn sets the guide roll 30c into rotation and brings about the feeding of the adhesive tape 40 to the cylindrical surface 21 of the cylindrical body 20. As a result of further rotation the adhesive tape 40 is wound onto the cylindrical surface 21 of the cylindrical body 20 and is stuck onto the cylindrical surface 21 of the cylindrical body 20 as a result of the pressure that exists between the lateral surface of the guide roll 30c and the cylindrical surface 21 of the cylindrical body 20. Before the cylindrical body 20 has performed a complete rotation about its cylindrical axis, the drive of the securing roll 30a is interrupted and the sectioning facility 50 cuts through the adhesive tape 40 and the liner 41. The drive of the securing roll 30a is then restarted and the cylindrical body 20 is rotated further about its cylindrical axis, until the cylindrical surface 21, as described already, is covered completely by a single layer of the adhesive tape. Lastly the insertion mechanism 60 is again moved from below onto the cylindrical body 20, until the cylindrical body 20 lies on the conveyor belts 61 of the insertion mechanism 60 and is raised from the securing roll 30a and the guide roll 30c, and the cylindrical body 20, to which adhesive tape has been stuck, is conveyed out of the sticking position by means of the conveyor belts 61.

(16) The embodiment shown in FIG. 3 differs from the embodiment shown in FIG. 2 essentially in that the liner 41 on the double-sided adhesive tape is removed from the adhesive tape 40 during the winding of the adhesive tape 40 onto the cylindrical surface 21 of the cylindrical body 20 and is wound on a liner winder 42. Consequently in this embodiment the outer surface of the cylindrical body 20 to which adhesive tape has been stuck is sticky, so the securing rolls 30 and also the conveyor belts 61 of the insertion mechanism 60 are designed to be adhesive-repellent (e.g. siliconised).

(17) The feed of the cylindrical body 20 into the sticking position is carried out in the manner described by means of the conveyor belts 61 of the insertion mechanism 60. In this embodiment, as soon as the sticking position has been reached, the cylindrical body 20 is raised from the conveyor belts 61 of the insertion mechanism 60 by the left lower securing roll 30a being moved up against the cylindrical body 20. In this embodiment the adhesive tape 40 can also be fed by driving of the liner winder 42, while the winding of the adhesive tape onto the cylindrical surface 21 of the cylindrical body 20 takes place in turn as a result of the driving of one of the securing rolls 30a, 30b. A sectioning facility 50 is again used to cut the adhesive tape 40 to length, though in this embodiment only the adhesive tape 40, not the liner 41, is cut through.

(18) The cylindrical body 20 to which adhesive tape has been stuck is removed lastly in the manner already described, whereby in this embodiment the cylindrical body 20 to which adhesive tape has been stuck leaves the device with a sticky surface, allowing immediate further processing of the same.

(19) The device and the method have been described with examples of embodiments that serve to clarify the invention, though they should not restrict the scope of protection defined by the claims. If applicable, any of the individual features presented in the individual exemplary embodiments can be combined with each other and/or replaced, without leaving the scope of the invention.

LIST OF REFERENCE SIGNS

(20) 10 device for applying adhesive tape 20 cylindrical body 21 cylindrical surface 30 securing rolls 30a, 30b movable/driven securing rolls 30c guide roll 32 vacuum zone 40 adhesive tape 41 liner 42 liner winder 45 roll of adhesive tape 50 sectioning facility 60 insertion mechanism 61 conveyor belts