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Title:
METHOD AND APPARATUS FOR WINDING WEBBED MATERIAL WITH MANDREL POSITION CONTROL
Document Type and Number:
WIPO Patent Application WO/2013/088276
Kind Code:
A1
Abstract:
A method and apparatus for winding a moving web upon a mandrel is disclosed. A moving web with a leading edge is conveyed towards a mandrel. The mandrel is adapted to allow the moving web to adhere to the mandrel at a specific circumferential location on the mandrel. To enable control of the location of the mandrel, the mandrel further includes a reference input to identify the specific circumferential location. A position sensor is used to determine the position of the reference input. The position of the specific circumferential location of the mandrel is controlled with a position drive control that controls the rotational speed of the mandrel. The position drive control sets the rotational speed of the mandrel to allow transfer of the leading edge of the moving web near the specific circumferential location.

Inventors:
BIXLER GREGORY MICHAEL (US)
HEINZ DANIEL MARK (US)
KARANDIKAR VIVEK MORESHWAR (US)
HADA FRANK STEPHEN (US)
BAGGOT JAMES LEO (US)
Application Number:
PCT/IB2012/056170
Publication Date:
June 20, 2013
Filing Date:
November 05, 2012
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
KIMBERLY CLARK CO (US)
International Classes:
B65H18/08; B65H43/00; B65H77/00
Foreign References:
US20110095116A12011-04-28
US20070017188A12007-01-25
US5441212A1995-08-15
US6595459B22003-07-22
US5211391A1993-05-18
US0028353A1860-05-22
JPS61114950A1986-06-02
US4133495A1979-01-09
US5337968A1994-08-16
US5797559A1998-08-25
US20030160127A12003-08-28
US7909282B22011-03-22
US8042761B22011-10-25
Other References:
See also references of EP 2791038A4
Attorney, Agent or Firm:
SULLIVAN, Michael, J. et al. (Neenah, WI, US)
Download PDF:
Claims:
What is claimed is:

1. A method of winding a moving web upon a mandrel comprising: conveying a moving web having a leading edge; providing a mandrel, the mandrel being adapted to adhere the moving web at a specific circumferential location on the mandrel, the mandrel further including a reference input to identify the specific circumferential location; engaging the mandrel with a position drive control to control the rotational speed of the mandrel; determining the position of the reference input with a position sensor; setting the rotational speed of the mandrel to allow transfer of the leading edge of the moving web near the specific circumferential location; transferring the moving web to the mandrel near the specific circumferential location; and winding the moving web.

2. The method of claim 1 wherein the mandrel is a coreless mandrel.

3. The method of claim 2 wherein the specific circumferential location on the mandrel is a line of vacuum openings.

4. The method of claim 2 wherein the specific circumferential location on the mandrel is a line of engagement fingers.

5. The method of any of the preceding claims further comprising loading a core onto the mandrel, and wherein the specific circumferential location on the mandrel is a strip of adhesive.

6. The method of any of the preceding claims wherein transfer of the moving web to the mandrel near the specific circumferential location occurs within plus or minus 15 degrees of rotation of the specific circumferential location.

7. The method of any of the preceding claims wherein transfer of the moving web to the mandrel near the specific circumferential location occurs within plus or minus 10 degrees of rotation of the specific circumferential location.

8. The method of claim 1 further comprising a registration system including an imaging system, wherein the imaging system senses a position of the leading edge of the moving web, compares the position of the leading edge of the moving web to the specific circumferential location, and then alters the position of the leading edge of the moving web or the specific circumferential location to correct for a position mismatch.

9. An apparatus for the method of winding a moving web upon a mandrel of any of the preceding claims comprising; a conveying surface for conveying a moving web; a mandrel, the mandrel being adapted to receive the moving web at a specific circumferential location on the mandrel, the mandrel further including a reference input to identify the specific circumferential location; a position sensor to determine the position of the reference input; and a position drive control to control the rotational speed of the mandrel.

Description:
METHOD AND APPARATUS FOR WINDING WEBBED MATERIAL

WITH MANDREL POSITION CONTROL

BACKGROUND

Winders are machines that roll lengths of paper, commonly known as paper webs, into logs. Winders are capable of rolling lengths of web into logs at high speeds through an automated process. Turret winders are well known to those skilled in the art. Conventional turret winders contain a rotating turret assembly which supports a plurality of mandrels for rotation about a turret axis. The mandrels travel in a circular path at a fixed distance from the turret axis. The mandrels engage hollow cores upon which a paper web can be wound. Typically, the paper web is unwound from a parent roll in a continuous fashion, and the turret winder rewinds the paper web onto the cores supported on the mandrels to provide individual, relatively small diameter logs. The rolled product log is then cut to designated lengths into the final product. Final products typically created by these machines and processes are toilet tissue rolls, paper toweling rolls, paper rolls, and the like.

The winding technique used in turret winders is known as center winding. A center winding apparatus, for instance, is disclosed in U.S. Patent Reissue No. 28,353 to Nystrand, which is incorporated in its entirety herein by reference. In center winding, a mandrel is rotated in order to wind a web into a roll/log, either with or without a core. Typically, the core is mounted on a mandrel that rotates at high speeds at the beginning of a winding cycle and then slows down as the size of the rolled product being wound increases, in order to maintain a constant surface speed, approximately matching web speed. Center winders work well when the web that is being wound has a printed, textured, or slippery surface. Also, typically, center winders are preferable for efficiently producing soft-wound, higher bulk rolled products.

A problem found in center winders is that they are typically not able to precisely position the mandrel for transfer. Thus, when using a core on the mandrel, glue must be applied to the entire circumference of the mandrel. This is typically done by applying glue in rings to the surface of the core. It can be seen that the spaces between the glue rings do not pick up the sheet which can lead to a missed transfer. Also, it can be seen that the glue that is not directly at the transfer point is not used and is wasted. A similar issue is present when using vacuum to transfer a sheet to a mandrel. If vacuum holes are spread out on the surface of the mandrel the overall vacuum level is lower than if the holes are placed in a line. It can be seen that a single line of glue is better able to hold a sheet and maximizing the effectiveness of the glue used. When a coreless mandrel is used with holes spread out on the surface of the mandrel, failure to securely attach to the mandrel may cause waste in the system or even potential machine shut-down. Thus, there is a need to provide an apparatus and method that controls the rotational mandrel position to allow for more precise control and efficient operation of the winder. SUMMARY

A method and apparatus for winding a moving web upon a mandrel with mandrel position control is disclosed. An attachment means is placed longitudinally along the length of the mandrel at a specific circumferential location on the mandrel, wherein the registration of the mandrel with the drive control facilitates the subsequent placement of moving web at the specific circumferential location upon the outer periphery of the mandrel. This process enables adhesion of the moving web to the mandrel at a predetermined and specific location. The system is designed to reduce cost, increase production output, and avoid excess waste of adhesive. Specifically, a moving web with a leading edge is conveyed towards a mandrel. The mandrel is adapted to allow the moving web to adhere to the mandrel at a specific circumferential location on the mandrel. The specific circumferential location is an axial or longitudinal area along the length of the mandrel. To enable control of the location of the mandrel, the mandrel further includes a reference input to identify the specific circumferential location. A position sensor is used to determine the position of the reference input. The position of the specific circumferential location of the mandrel is controlled with a position drive control that controls the rotational speed of the mandrel by torque applied at one or each end of the mandrel. The position drive control sets the rotational speed of the mandrel to allow transfer of the leading edge of the moving web near the specific circumferential location.

The transfer typically occurs so that the moving web attaches to the mandrel within plus or minus 15 degrees of rotation of the specific circumferential location. More desirably, transfer typically occurs so that the moving web attaches to the mandrel within plus or minus 10 degrees of rotation of the leading edge of the sheet for a good coreless transfer on a coreless execution or cored transfer when using cores.

A method and apparatus for winding a moving web upon a mandrel with mandrel position control may be utilized to produce a coreless product. A "coreless" product is one which does not have a separate, relatively rigid, independent, non-tissue core component, such as a cylindrical cardboard core typically used for commercially available tissue products. In this type of product, the process includes controlling the rotational speed of the mandrel to allow transfer of the leading edge of the moving web near a strip of vacuum openings or engagement fingers for the specific circumferential location.

A method and apparatus for winding a moving web upon a mandrel with mandrel position control may be utilized to produce a traditional rolled product with a core. In this type of product, the process includes loading a core onto the mandrel, and controlling the rotational speed of the mandrel to allow transfer of the leading edge of the moving web near a strip of adhesive for the specific circumferential location. The adhesive for this method is arranged on the surface of the core in a substantially linear fashion parallel to the axis of the mandrel. The glue line can be continuous or discontinuous if less adhesion is needed.

BRIEF DESCRIPTION A full and enabling disclosure thereof, directed to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, which makes reference to the appended figures in which:

Figure 1 illustrates a schematic view of a rewinder using the mandrel position control of this invention; and Figure 2 illustrates a schematic view of a mandrel for use in the embodiment depicted in Figure 1.

DETAILED DESCRIPTION Reference now will be made in detail to various embodiments of the invention, one or more examples of which are set forth below. Each example is provided by way of explanation, not limitation. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made in the present disclosure without departing from the scope or spirit of the claims. For instance, features illustrated or described as part of one embodiment, may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the claims cover such modifications and variations.

As described above, as moving webs of material are manufactured into a rolled product on various types of winders, the moving web needs to be placed onto the mandrel. Generally, a method and apparatus for winding a moving web upon a mandrel is disclosed. A moving web with a leading edge is conveyed towards a mandrel. The mandrel is adapted to allow the moving web to adhere to the mandrel at a specific circumferential location on the mandrel. The specific circumferential location is an axial or longitudinal area along the length of the mandrel. This axial or longitudinal area along the length of the core could be a plurality of engagement fingers, a plurality of openings which can be used for vacuum, or a line of adhesive on a core to enable the moving web to adhere to the mandrel for winding.

To enable control of the location of the mandrel, the mandrel further includes a reference input to identify the specific circumferential location. The reference input may be a flag or a marking that corresponds to the specific circumferential location on the mandrel. A position sensor is used to determine the position of the reference input. It is also possible that the specific circumferential position can be detected using an imaging system as the position sensor that can analyze a video signal of the mandrel rotation as well as the position of the leading edge of the moving web. The position of the specific circumferential location of the mandrel is controlled with a position drive control to control the rotational speed of the mandrel using torque applied at one or each end of the mandrel. In one application, a belt and pulley system may be used to apply torque to the mandrel. Desirably, the mandrel is attached to a pulley and engaged by a flat metered winding belt. The flat metered winding belt is driven by a metered winding drive pulley. Other position drive controls may be used including, but not limited to, timing belts, gearing or pulleys, rotational surface friction, magnetic flux, and other means known by persons of skill in the art. The position drive control sets the rotational speed of the mandrel to allow transfer of the leading edge of the moving web near the specific circumferential location.

A rolled product is then created by winding the moving web on the mandrel into a finished rolled product. The mandrel is rotated at changing rotational velocity so that the web speed and the winding profile may be controlled as the rolled product builds. In most cases, the axial position of the mandrel may change gradually by mechanical means such as conveyor or timing belt drive speed changes, cam track, or a rocker arm as the log diameter increases to minimize web interference with machine components during winding. Then, when the desired length of webbed material has been wound upon the cored mandrel into a finished log, the web is severed and transferred to another incoming cored mandrel by standard bed roll means and the process begins once again on the next successive mandrel.

The roll is spirally wound from the hole in the center of the roll to the outside, but effectively the roll can be thought to consist of a large number of windings, which are the individual layers or sheets between the axis and the outer surface as measured along a radial direction. A single winding represents the sheet being wound once around the roll. Typically, bath tissue rolls made from through-air dried tissue have from about 150 to about 250 windings per roll. The actual number of windings will depend upon the sheet count, the final desired diameter of the roll and the thickness of the tissue sheets, but these are typical values for commonly made products available for consumers. Similarly, single- ply paper towels made from through-air dried tissue have from about 50 to about 150 windings per roll.

The disclosed method of mandrel position control is based on finding a specific circumferential location or position on the mandrel. A means for identifying this specific circumferential location or position on the mandrel is incorporated on the mandrel.

Specifically, a mandrel rotational position sensor that is mounted on the machine frame detects the reference input on the mandrel to indicate to the control of the machine where the specific circumferential location is currently situated.

In typical applications, the exact position of the mandrel is lost during removal of the wound roll and needs to be found by the sensor to re-establish the circumferential position. The mandrel is turned slowly until the mandrel rotational position sensor detects the reference input on the mandrel and stops. At this point the mandrel is in a known rotational position. The machine controls are then programmed with a specific winding cam that caused the flat drive belt to be moved in order to place the specific circumferential position in the proper rotational position to be in time with the leading edge of the sheet for proper transfer.

Transfer typically occurs so that the moving web attaches to the mandrel within plus or minus 15 degrees of rotation of the specific circumferential location. More desirably, transfer typically occurs so that the moving web attaches to the mandrel within plus or minus 10 degrees of rotation of the leading edge of the sheet for a good coreless transfer on a coreless execution or cored transfer when using cores.

Typical center winder operations do not detect the mandrel position and do not place the mandrel rotational position in the proper time with the leading edge of the sheet. The conventional operation requires rings of adhesive around a typical core for transfer of the sheet to the mandrel. The disclosed method and apparatus also differs from a standard registration system that senses an eye mark or registration mark. These systems typically sense a position of the sheet and then advance or retard the sheet or the mandrel position to correct for position mismatches by comparing the two relative to each other. The mandrel position would have to be known or always in contact with a drive means so that its position is always known. This is not the case in the method and apparatus described herein since the mandrel is not in contact with the drive belt for a significant portion of the turret movement. This registration feature could be added as an additional feature for the mandrel position control above using an imaging system to compare mandrel position and the sheet leading edge for fine tuning. Figure 1 illustrates a center rewinder 100 with a turret assembly 1 10 that may be employed in the method of winding a web disclosed herein. Turret assemblies are well known to those skilled in the art to be useful for winding paper onto a mandrel. In general, turret assemblies often include at least one mandrel that is rotatably affixed to an indexing mechanism. The indexing mechanism, or turret, can rotate a mandrel into a number of positions or "stations" at which various steps of the winding process can occur. For instance, at one position, the moving web can be attached to the mandrel. At another position, the moving web can be wound around the mandrel. And, at yet another position, the wound rolled product can be removed from the mandrel. Any turret assembly known to those skilled in the art is suitable for use in the present invention. Examples of various turret assemblies that can be used in the present invention include, but are not limited to, the turret assemblies described in U.S. Patent No. 4,133,495 to Dowd; U.S. Patent No. 5,337,968 to De Bin et al; and U.S. Patent No. 5,797,559 to Coffey, which are incorporated in their entirety herein by reference. Other winding systems that may be used in accordance with the present disclosure include the winders disclosed in U.S. Patent Application Publication No. US2003/0160127 to Wojcik et al, U.S. Patent No. 7,909,282 to Wojcik et al., and U.S. Patent No. 8,042,761 to Wojcik et al., which are all incorporated herein by reference.

In this embodiment, a bedroll 102 defines a conveying surface 104 of the center winder 100. In an exemplary embodiment, the bedroll 102 rotating in the direction of the arrow represented by arrow 103 may also be a vacuum transfer roll utilized to hold the moving web 136 on the conveying surface of the rotating roll 102. The moving web is moving in the direction of the arrow represented by number 101. A web cut-off assembly 190 is mounted in proximity to the bedroll 102 to cause a break in the moving web 136 when a web break is desired.

The turret assembly 110 is rotatably mounted below the bedroll 102 and rotating in the direction of the arrow represented by number 107. The turret assembly 110 further includes a plurality of rotating mandrels such as winding position mandrel 112 where paper is wound upon a core. Typically, the centerline of the turret is directly in line with the centerline of the bedroll.

The winding position defined as the "core load position," which is the position occupied by mandrel 113. In this position, on at least one end of the mandrel, a mandrel pulley 146 is attached to at least one end of the mandrel 113. The mandrel pulley 146 interacts with the position drive control 140 to control the rotational speed of the mandrel by torque applied at one or each end of the mandrel.

In embodiments where a core is desired to be included with the final rolled product, the winding process can be initiated by the "core load position," by first placing a core onto the mandrel according to any method known in the art. Once the core is placed onto mandrel 113, the turret assembly 110 can then be indexed into an "adhesive application position," which is the position occupied by mandrel 114. In particular, an adhesive can be applied to the specific circumferential position by any method known in the art to the core. Generally, the adhesive used can comprise any of a variety of materials, such as glue, known to adhere paper to a surface. Although not necessarily required, such an adhesive facilitates attachment of the paper web onto a core. While rings of adhesive are usually places on the core in this position, it is also possible to apply a line of adhesive at the reference position. It is typical to have a small drive (not shown) to slowly rotate the cored mandrel to apply glue. The same drive can be used to index the core to the correct position to apply a line of adhesive.

In coreless executions of the rolled product, no core or adhesive is placed onto the mandrel. Alternative attachment means such as vacuum suction or temporary mechanical attachments described in more detail below are used to adhere the moving web to the specific circumferential location. Once adhesive or other attachment means is applied to the mandrel, the mandrel can be indexed by turret 110 into the "pre-spin position," which is the position occupied by mandrel 116. At this position, the specific circumferential location of the mandrel is controlled to allow transfer of the leading edge of the moving web near the specific circumferential location. To enable control of the location of the mandrel, the mandrel further includes a reference input 138 as illustrated in Figure 2 to identify the specific circumferential location. The reference input 138 may be a flag or a marking that corresponds to the specific circumferential location on the mandrel. A position sensor 156 is used to determine the position of the reference input 138.

The position of the specific circumferential location of the mandrel is controlled with a position drive control 140 to control the rotational speed of the mandrel using torque applied at one or each end of the mandrel. In one application, a belt and pulley system may be used to apply torque to the mandrel. Desirably, the mandrel is attached to a pulley 146 that engages by a flat metered winding belt 142. The flat metered winding belt 142 is driven by a metered winding drive pulley 144. The position drive control 140 sets the rotational speed of the mandrel to allow transfer of the leading edge of the moving web near the specific circumferential location. The position drive control 140 is only in contact with the mandrel at the "pre-spin position," the "winding position" and until just before the "tail-seal position," and not in contact with the mandrel throughout the turret assembly. This requires the mandrel position control system 100 to interact with the mandrel and find the position of the reference input to match the leading edge of the sheet each time. It is important to note that only one flat metered winding belt 146 is shown in

Figure 1 to illustrate the principle of this invention. There are actually two metered winding belts on a machine to allow winding on the previous mandrel in position 112 while the next mandrel is in the "pre-spin position" getting up to the operating speed in preparation for transfer. At the "pre-spin position," the mandrel may then be rotated to ensure that the mandrel achieves a certain rotational speed before the paper web is wound thereon. The mandrel 26, for instance, can be accelerated to a speed wherein the surface speed of the mandrel substantially matches the surface speed of the web 136. For instance, the mandrel may be rotated at a speed that is equal to, slightly greater than or slightly less than the speed of the moving web. As used herein, for instance, indicating that the mandrel is accelerated to a rotational speed that is "substantially" equal to a speed at which the tissue sheet is moving refers to the fact that the mandrel speed is within about 10 percent of the speed of the tissue sheet. In other embodiments, however, the mandrel speed may be within about 5 percent, such as within about 2 percent of the speed of the tissue sheet. In still another embodiment, the mandrel may be accelerated so as to be at the same speed or slightly greater than the speed of the tissue web. Additionally, the mandrel is indexed at the moment of transfer so that the specific circumferential position may meet the leading edge of the moving web.

Once the mandrel is set into the proper location at the "pre-spin position" so that the specific circumferential position may meet the leading edge of the moving web, the mandrel can then be indexed by the turret assembly 110 into the "winding position," which is the position occupied by mandrel 112. A transfer device 127 may be used to move the moving web 136 from the bedroll 102 to the turret assembly 110 near the specific circumferential position of the mandrel 112. The transfer device 127 can be mounted onto a bearing and driven by any suitable driving device 129, such as an actuating cylinder as is illustrated in Figure 1 or a cam mechanism. The rotational speed of the mandrel imparted at the "pre-spin position," is generally greater than the feed speed of the paper web such that, as the rotating mandrel is indexed into the "winding position," the paper web can wind around the mandrel. Moreover, mandrel 112, for example, can be further rotated in a clockwise direction, while in the "winding position", such that moving web 136 can be wound thereon. In some embodiments, the rotational speed of mandrel 112 can be controlled such that the surface speed of the winding log maintains a substantially constant rate from the time that it first contacts the leading edge of paper web 136 until the end of the winding period. After winding of the web is complete, the web cut-off assembly 190 acts to break the moving web to create a new rolled product.

After the moving web 136 is wound onto the mandrel, it can then be further indexed by turret 110 into a "tail seal position", which is the position occupied by mandrel 118. At the "tail seal position", the unattached portions of web 136 can be sealed to the roll of paper via a sealing device (not shown). In some embodiments, for example, the sealing device can be configured to apply glue or some other adhesive to the paper web such that the tail can be sealed thereto. An external roll (not shown) can also be used for rotating mandrel 118 at the "tail seal position," of this embodiment. As such, mandrel 118 can rotate at a slower speed, which can aid in the sealing process. In many applications, the tail seal is done on a separate tail sealing machine that is outside the rewinder. Once sealed, the finished rolled product can then be removed. In some embodiments, mandrel containing a finished roll of paper can be indexed by turret 110 into a "removal position," which is the position occupied by mandrel 120. A finished roll product can be axially removed from mandrel 120 by any method known in the art.

As described throughout the application, the mandrel is adapted to provide an attachment means to allow the moving web to adhere to the specific circumferential location 150 on the mandrel. As illustrated in Figure 2, this specific circumferential location 150 is an axial or longitudinal area along the length of the mandrel. This axial or longitudinal area along the length of the mandrel 134 could be a plurality of engagement fingers, a plurality of openings, or a line of adhesive to enable the moving web to adhere to the mandrel for winding. Corresponding with the specific circumferential location 150 is reference input 138 that interacts with the position sensor to enable the mandrel control system 100 to correctly position the mandrel.

For one embodiment of coreless tissue products, in order to assist in placing the tissue web on the mandrel 134 the specific circumferential location 150 may include a plurality of openings and may be in communication with a vacuum source. In this manner, the mandrel forms a suction against the tissue web in order to at least initiate winding. In the case of a vacuum mandrel, the leading edge or slighted after the leading edge of the tissue web is lightly wetted prior to contact with the mandrel. Lightly wetting the tissue web allows for hydrogen bonds to form between the layers of the tissue web that are directly adjacent to the mandrel. The light hydrogen bonding allows for a passageway to be formed into the roll or log of material without compromising the tissue web. The layers of the tissue web are lightly bonded such that the layers can be separated during later use.

For another embodiment of coreless tissue products, in order to assist in placing the tissue web on the mandrel 134 the specific circumferential location 150 may include a plurality of retractable pins or engagement fingers. The retractable engagement fingers extend from the surface of the mandrel and perforate the tissue web for winding, such that the pins perforate two or more windings of the resulting roll of tissue, thereby forming a soft core. The engagement fingers need to be removed from the rolled product once finished to allow removal of the log. The engagement fingers are sharp, pointed, generally elongated tapered structures that are capable of piercing at least two windings of a tissue web. In general, the base of the engagement finger needs to be sufficiently large to provide the necessary strength needed to withstand the demands of high speed commercial manufacturing, where the mandrels rotate at speeds of from about 3000 to about 6000 revolutions per minute depending on sheet speed and mandrel diameter. The tips of the engagement fingers, which must also have sufficient strength and durability, are as sharp as reasonably possible in order to easily punch through sheets of tissue during the winding operation. In cross-section, the engagement fingers can be any shape, such as round, elliptical, square, triangular, etc. The length of the engagement fingers, as measured from the surface of the mandrel to the tip of the engagement finger, can be from about 0.1 to about 0.4 inch. The base of the engagement fingers can be from about 0.1 to about 0.3 inch in width. Testing has shown that the tip of the engagement finger needs to be sharp to penetrate the sheet. Suitable shapes for the engagement finger would be a pyramid or a cone ending at a tip. In all cases the engagement finger tapers in all directions to a point. A frustum of a pyramid or cone, where the tip has a significant width, would not be suitable for use as an engagement finger because such structures would not penetrate more than one sheet, if at all. By way of example, a typical engagement finger suitable for purposes herein will have a point comparable to that of the transfer engagement fingers currently used in the bedroll of rewinder lines, such as those manufactured by the Paper Converting Machine Company, Green Bay, WI. Another more common example is that the sharpness of the engagement finger would be similar to a common safety thumb tack. A suitable material for making the engagement fingers includes spring steel hardened to about 40 on the Rockwell "C" scale. This level of hardening provides good durability and wear resistance.

In the embodiment with a product including a core, in order to assist in placing the tissue web on the mandrel 134 the specific circumferential location 150 may include a line of adhesive. The speed of the overall process may be increased by applying glue axially along the length of the core. For example, prior art methods which applied glue to the entire exterior surface of the core, all the way around the circumference, tended to be wasteful and caused maintenance clean up problems due to excessive amounts of glue being thrown by centrifugal force upon the machinery during core rotation. The adhesive may be applied in a solid line or a series of solid lines, or may be applied in an interrupted line. Only the amount of adhesive actually needed to adhere paper to the core is provided.

In another embodiment, a mandrel is permanently attached to a drive mechanism and the position of the circumferential location 150 is known at all times. It is then possible to synchronize the leading edge of the sheet with the circumferential location at all times without the need to find the reference mark on the mandrel. Other modifications and variations to the appended claims may be practiced by those of ordinary skill in the art, without departing from the spirit and scope as set forth in the appended claims. It is understood that features of the various examples may be interchanged in whole or part. The preceding description, given by way of example in order to enable one of ordinary skill in the art to practice the claimed invention, is not to be construed as limiting the scope of the invention, which is defined by the claims and all equivalents thereto.