Drum Winder and Method for Drum Winding a Web

The present invention relates to a drum winder including winding drums that support a roll that is being formed, i.e., onto which a web is being wound, and which is provided with a cutter device for cutting the web after the roll has reached a desired size and before the web begins to wind onto a new empty roll spool. The cutter device comprises a cutter blade, an actuator, and power transmission means operationally connected to the cutter blade of the cutter device so that the movement of the actuator is transferable by means of the power transmission means to the cutter blade. In this manner, the cutter blade moves along a curved path of movement so that the position of the cutter blade in the lower position is substantially more distant from the winding drum than it is in the upper position.

The present invention also relates to a method for winding a web onto a roll in a drum winder in which the web is supported on winding drums and a gap formed between the winding drums and the roll is pressurized.

In drum winding, it is desirable to lower the linear nip loads produced by the weight of the growing roll, because otherwise the linear loads that act in the nips will become excessively high, causing defects in the roll.

With respect to the prior art, reference is made to the publications DE 1,047,001, DE 1,111,496, DE 3,618,955, and U.S. Pat. No. 3,497,151. In the devices described in these prior art references, it is known to pass a pressure into the gap formed by the roll that is being formed and by the winding drums, whereby a relief effect is applied to the roll that is formed. As a result of this effect, the linear loads in the nips cannot become excessively high. In order that the pressure should be retained in the gap formed by the roll and by the winding drums, it is known from the prior art to seal the gap from above and from below, respectively, by means of various sealing constructions. From the publication DE 1,047,001, it is known to move the upper roll-end sealing unit in an axial direction of the roll.

In addition, from U.S. Pat. No. 3,346,209, it is known to regulate the pressure present in the gap formed by the roll and the winding drums by moving the lower drum in a substantially vertical direction, i.e., up and down.

Even though by means of the prior art devices described above, considerable improvement in the winding of a web onto a roll is achieved, they involve certain drawbacks. For example, sealing of the gap formed by the roll that is formed and the winding drums is generally problematic. The pressure always leaks to some extent, which results in problems of dust formation. Owing to the leakage of the pressure, a very large quantity of air is needed to maintain the pressure, which air spreads into the working environment, for which reason the dust is readily separated from the web that is wound and spreads into the working environment.

Moreover, the prior art devices restrict or at least hamper some operations that are necessary in the roll formation. One of these operations is the roll change wherein when the roll that is being wound becomes complete, a new roll spool must be fed into the gap between the winding drums, the web that is wound must be cut off, and the end of the cut-off web must be attached to the new roll spool. Thus, during roll change operations, various actuators are needed, such as web holders, cutting means, devices for the feed of a new roll spool, etc.

In the assignee's Finnish Patent Application No. 902890 of earlier date (corresponding to the assignee's U.S. patent application Serial No. 07/713,137, the specification of which is incorporated by reference herein), a cutter device is described for a web winder. The cutter device comprises a frame construction and a cutter blade for cutting the web in the roll formed on support of the winding drums before a new winding is started onto an empty roll spool. The cutter device comprises an actuator and power transmission members operatively connected to the cutter blade of the cutter device so that the movement of the actuator is transferable by means of the power transfer members to the cutter blade. In this arrangement, the cutter blade is movable along a curved path of movement so that the position of the cutter blade in its lower position is substantially more distant from the carrier drum than in its upper position. If necessary, such a cutter device may be connected with a blower device for holding the cut-off web end, a web holder, and/or a threading member for the web being wound onto the new, empty roll spool. The cutter blade of the cutter device moves along a curved path of movement into the gap between the winding drums, for example, from below the gap.

By means of a cutter device described in FI Pat. Appl. 902890, an advantage is obtained in that it is not necessary to make any installation pit for the frame construction of the cutter device, e.g., in the floor of the production plant. The cutter device can be attached to the frame of any drum winder whatsoever. In addition, it is easy to attach other accessories to the cutter device that are necessary for carrying out the roll change operation. Such accessories include, for example, the above blower for holding the cut-off web end, the web holder, and the threading device, etc.

Accordingly, it is an object of the present invention to provide an improvement over the prior art methods of drum winding and drum winders.

It is another object of the present invention to provide a drum winder, and method for drum winding a web, that have the same advantages as so-called pressure winders but in which some drawbacks present in the prior art devices are avoided.

The objects of the invention stated above, and others, are achieved by providing a drum winder with seal units arranged on the blade beam of the cutter blade so as to seal the winding drums from below, i.e., the open space or gap between the winding drums and the roll being formed. The upper regions of the gap between the winding drums are sealed by means of an upper end-seal unit in itself known. By sealing the from above by means of the end seal units and roll being formed and from below by means of the seal units, the gap between the winding drums can be pressurized.

By means of the drum winder in accordance with the invention, the same advantages are obtained as by means of so-called pressure winders known from the prior art. However, in the drum winder in accordance with the invention, the actuators necessary for the roll change are already present, for which reason the invention does not produce any problems in the operation of the roll change devices. Also, the sealing problems symptomatic of the gap formed by the roll that is formed and by the winding drums is, in the drum winder in accordance with the invention, solved so that drawbacks present in the prior art devices are avoided.

In the method in accordance with the invention, a web is wound onto a roll supported on winding drums and a gap is formed between the roll and the winding drums. A cutter blade is arranged on a blade beam and then moved between a first position in which the cutter blade is distant from one of the winding drum and a second position in which the cutter blade operates against that winding drum. Sealing means are arranged on the blade beam for sealing a region of the gap between the winding drums and opposite the roll when the cutter blade is in the second position. In addition, end regions of the gap can be sealed such that the gap is completely sealed, and then can be pressurized. The sealing means may be positioned against a second one of the winding drums opposite the winding drum against which the cutter blade operates when the cutter blade is in the second position, and to provide a complete seal of the gap, an end seal is arranged between the blade beam and the cutter blade. The gap can be pressurized by directing air through the blade beam into the gap.

The invention will be described in detail with reference to some preferred embodiments of the invention illustrated in the figures in the drawing. The invention is, however, not confined to these embodiments alone.

The following drawings are illustrative of embodiments of the invention and are not meant to limit the scope of the invention as encompassed by the claims.

FIG. 1 is a side view of a prior art drum winder having a web cutter.

FIG. 2 is a side view of a first preferred embodiment of the drum winder in accordance with the present invention in the sealing/cutting position, and which is used in the method in accordance with the invention.

FIG. 3 is a side view of the drum winder as shown in FIG. 2 in the threading/cleaning/start-run position.

FIG. 4 is a side view of a second preferred embodiment of the drum winder in accordance with the invention in the sealing/cutting position, and which is used in the method in accordance with the invention.

FIG. 5 is a side view of the drum winder as shown in FIG. 4 in the threading/cleaning/start-run position.

FIG. 6 is a side view of a third preferred embodiment of the drum winder in accordance with the invention in the sealing/cutting position, and which is used in the method in accordance with the invention.

FIG. 7 shows the embodiment as shown in FIG. 6 in the threading/cleaning/start-run position.

FIG. 8 shows a fourth preferred embodiment of the drum winder in accordance with the invention in the sealing position, and which is used in the method in accordance with the invention.

FIG. 9 shows the embodiment as shown in FIG. 8 in the threading/cleaning/start-run position.

Referring to the drawings, wherein the same reference numerals refer to the same elements, FIG. 1 shows a prior art cutter device 10 arranged for use in a drum winder. The cutter device 10 comprises a frame 11, a synchronizing pipe 12, a first set of pivotally fitted arms 13, a second set of pivotally fitted arms 14, a cutter blade 16, a frame or blade beam 15 for supporting the cutter blade 16 and an actuator 17 coupled at one end to the frame 11 and at an opposite end to the pipe 12. The frame 11 includes a frame pipe 11a arranged at one end thereof. The frame pipe 11a passes in the transverse direction through the drum winder to the other side. In FIG. 1, the cutter device 10 is applied to a drum winder that comprises an ordinary winding drum 18 and a winding drum 19 formed by a roll 19a and a second roll, which is not shown, and a belt 19b. The web roll 20 is formed as a web is wound thereon after passing over winding drum 18. The cutter blade 16 of the cutter device 10 is passed into the gap between the winding drums 18 and 19 from below the gap, or through any existing opening into the gap between the winding drum 18, roll 19a and roll 20. The cutter device 10 is attached to the frame construction of the drum winder by suitable means (not shown).

The cutter device 10 as shown in FIG. 1 operates as follows. The movement of the actuator 17, such as a hydraulic cylinder, acts upon the first set of arms 13, which are linked with the second set of arms 14 via a pivot point. The pivoting movement of the arms 13 is synchronized by means of the synchronizing pipe 12. The frame 15 of the cutter blade 16 is linked with the second set of arms 14. The movement of the actuator 17 is transferred by means of the arms 13 and 14 to the frame 15. As such, upon movement of the actuator, the frame 15 of the cutter blade 16, and the blade 16 attached thereto, causes a curved rotating movement of the blade 16 in relation to the face of the winding drum 18. This curved movement of rotation is selected so that the center of rotation of the circular movement of the cutter blade 16 is separate from the center of rotation of the winding drum 18. The center of rotation of the blade 16 can be freely selected as long as the center of rotation of the blade 16 does not coincide with the center of rotation of the winding drum 18. In FIG. 1, the dashed lines indicate the lower position of the cutter blade 16 and cutter device 10, and the corresponding solid lines indicates the upper position of the blade 16 and cutter device 10. As shown clearly in FIG. 1, in the lower position the cutter blade 16 is at a certain distance from the face of the winding drum 18, and in the upper position the cutter blade 16 is very close to the face of the winding drum 18.

The cutting proper of the web takes place because the blade 16 is sufficiently sharp to pierce the web that is placed tight on the roll 20. Alternatively, cutting of the web placed on the roll 20 may also take place so that the roll 20 is pushed by means of an ejector device in itself known, in which case the tight web forms a sufficient angle in relation to the cutter blade 16 causing the web to be cut off.

FIGS. 2 and 3 show the application of the present invention to the prior art device illustrated in FIG. 1. As shown in FIGS. 2 and 3, a sealing doctor blade 21 is arranged on the blade beam 15 of the cutter blade 16. An end seal 22 is arranged on the blade beam 15 between the doctor blade 21 and the cutter blade 16. An upper end seal 23 is arranged between the winding drums or rolls 18,19 and the roll being formed (not shown) which is supported by the winding drums or rolls 18,19. FIG. 2 shows the position of the blade beam of the cutter device 10 in its upper position in which the cutter blade 16 is in a position to cut the web against the face of the winding drum 18. The doctor blade 21 seals the space between the cutter device and the roll 19 as it abuts against the surface of the roll 19. FIG. 3 shows the position of the blade beam 15 of the cutter device 10 in its lower position when the cutter blade 16 is spaced from the winding drum 18.

In the gap between the ,winding drums 18 and 19, it is possible to supply air through the blade beam 15 in order to produce pressure in the gap. The blade beam 15 may, of course, be a sealing beam only in which case pressurized air is supplied into the gap between the winding drums 18 and 19 in some other way in order to produce pressure.

The embodiment shown in FIGS. 4 and 5 is in most respects similar to that shown in FIGS. 2 and 3 and can also be applied to the cutter device 10 shown in FIG. 1. However, in the embodiment of FIGS. 4 and 5, instead of the sealing doctor blade, a seal plate 121 is used to seal the space between the blade beam 15 of the cutter device 10 and the face of the winding drum 19. The seal plate 121 is preferably a curved seal plate having a curvature corresponding to the curvature of the winding drum 19. An end seal 122 of the beam is arranged on the seal plate to seal any gap or space between the seal plate 121 and the cutter blade 16. In this embodiment, the supply of air into the gap between the winding drums 18 and 19 can be carried out through the blade beam 15, or the blade beam 15 may operate as a seal unit itself, in which case the air is supplied in some other way in itself known in order to produce pressure in the gap between the winding drums 18 and 19.

In the embodiment shown in FIGS. 6 and 7, the sealing of the gap between the winding drums 18 and 19 from below, i.e., opposite to the roll being formed, is produced by means of an end seal 222 having one seal part situated on the blade beam 15 and another similar seal part situated on a stationary box 221 positioned adjacent to the winding drum 19. An intermediate seal 223 is arranged between the blade beam 15 and the stationary box 221, underneath the end seal 222, and is coupled to either the stationary box 221 or the blade beam 15. If necessary, the stationary box 221 can be lowered, e.g., to clean or move the winding drum 19. Also in this embodiment, air can be supplied into the gap between the winding drums 18 and 19 as described in the preceding embodiments.

In the embodiment shown in FIGS. 8 and 9, the cutter blade 16 has been removed from the beam 15, and a seal roll 321 is arranged on the beam 15. An end seal 322 is arranged on the seal roll 321 to seal the gap between the winding drums from below. Air can be supplied into the gap between the winding drums 18 and 19 as described in the preceding embodiments, e.g., air can be supplied through the blade beam 15 or the seal roll 321 into the gap to pressurize the same. The web is cut when necessary by cutting means not shown in the illustrated embodiment.

Although, the invention is described with reference to FIGS. 2-9 in relation to the prior art cutter device shown in FIG. 1, the invention can also be applied equally as well in other cutter devices, such as those pressure winders having a pressurized gap between the winding drums and the roll being formed as a web is wound thereon.

The examples provided above are not meant to be exclusive. Many other variations of the present invention would be obvious to those skilled in the art, and are contemplated to be within the scope of the appended claims.