Log saw apparatus and method

Information

  • Patent Grant
  • 6718853
  • Patent Number
    6,718,853
  • Date Filed
    Wednesday, April 24, 2002
    22 years ago
  • Date Issued
    Tuesday, April 13, 2004
    20 years ago
Abstract
Some preferred embodiments of the present invention includes an apparatus and method employed for cutting a rotating log of rolled product into rolls, the apparatus and method utilized for preventing collapse of a longitudinally extending aperture in the log during the cutting process. The present invention includes a mandrel received within the aperture of the log to at least partially support the log and to preferably maintain the integrity of the aperture while the log is being cut by a saw blade. Preferably, the mandrel has at least one recess within which a saw blade can be received during cutting operations upon the log.
Description




FIELD OF THE INVENTION




The present invention relates to saw assemblies for wound products, and more particularly to saw assemblies having mandrels for at least partially supporting the wound products while they are being cut by a log saw.




BACKGROUND OF THE INVENTION




Rolled products, such as bathroom tissue, paper toweling, wax paper, foil, plastic sheeting, fabric, or other material found in sheet form are typically produced in two ways. The rolled products are produced either with a core at the center of the roll or without a core at the center of the roll. Due to cost and manufacturing limitations associated with the use of a core, it has become advantageous to produce coreless rolled products. However, to allow a coreless product to be used with existing dispensers designed for cored rolled products, it is typically necessary to include a longitudinally extending aperture through the coreless rolled product.




Coreless rolled products are typically produced on winding mandrels to create the central aperture that extends along the longitudinal axis of the rolled product. The winding mandrel forms a relatively long log of rolled product that is later cut into usable lengths or rolls by a saw blade. A disadvantage of coreless rolled products is that the center aperture has the tendency to collapse when the log is being cut into rolls by the saw blade. Even in rolled products having a core, the amount of force exerted upon the rolled product during some cutting operations can cause the core to deform or collapse if not at least partially supported by a mandrel. For example, some rolled products can be easily deformable or can require larger cutting forces capable of bending, deforming, crushing, or otherwise damaging the rolled product if not supported by a mandrel. Additional design limitations arise due to the conventional practice of cutting logs with a saw that must pass through a length equal to the diameter of the log in order to completely cut the log. A blade that must pass this deeply into the log can often generate significant friction, heat, and undesirable forces during cutting operations, and can result in poor cuts and poor product quality.




Different methods have been developed to alleviate this problem in rolled products with or without cores. For example, tightening the wind of the coreless rolled product can increase the stiffness and rigidity of the rolled product, thereby reducing the amount of aperture collapse. Although this solution can reduce collapse, it can also increase the friction between the saw blade and the log, thereby increasing the difficulty of cutting the log into rolls and calling for larger cutting forces.




In combination with or as an alternative to tightening the wind of a rolled product, some saw assemblies include a mandrel that is received within the aperture of the log to maintain the shape of the aperture during the cutting process and to reduce the amount of aperture collapse. Some saw assemblies, such as the one disclosed in U.S. Pat. No. 5,271,137, include a mandrel positioned entirely on one side of the saw blade during cutting operations upon the log. The mandrel includes an end that is positioned adjacent to the saw blade to support the aperture when the saw blade moves through the log to cut a roll from the log. Other saw assemblies, such as the one disclosed in U.S. Pat. No. 5,453,070, include a first mandrel positioned on one side of the saw blade and a second mandrel positioned on the opposite side of the saw blade. Each mandrel includes an end positioned adjacent to the saw blade to support the aperture when the saw blade moves through the log between the ends of the mandrels. Although it is the intention of these saw assemblies to support the aperture close to the saw blade during the cut, these saw assemblies still allow a substantial amount of aperture collapse that can result in a poor quality cut. In addition, the use of two mandrels (and associated elements and equipment) adds significant cost to log cutting machinery.




In light of the above design requirements and limitations, a need exists for a saw assembly that includes a mandrel which provides superior support of the center aperture of a log during the cutting process, reduces the collapse of the aperture during the cutting process, and allows for the rotation of the logs during the cutting process so the saw blade cuts a roll from the log after passing through less than the diameter of the rotating log, thereby lowering the force and friction applied to the log by the saw blade. Each of the preferred embodiments of the present invention achieves one or more of these results.




SUMMARY OF THE INVENTION




In some preferred embodiments of the present invention, an apparatus and method are employed for cutting a rotating log into rolls utilized for preventing or reducing the collapse of a longitudinally extending aperture in the log during the cutting process. Some embodiments of the present invention preferably include a mandrel received within the aperture of the log to at least partially support the log and maintain the integrity of the aperture while the log is being cut by a saw blade. The mandrel can include a longitudinal axis, a first portion, and a second portion along the longitudinal axis. The first portion preferably includes a radially outermost surface defining a first radial distance from the longitudinal axis, and the second portion preferably includes a radially outermost surface defining a second radial distance from the longitudinal axis which can be the same or different from the first radial distance.




Preferably, the saw blade is movable toward the longitudinal axis to a cutting position between the first portion and the second portion. At the cutting position, the mandrel preferably has a third distance between the saw blade and the longitudinal axis, the third distance being shorter than at least one of the first and second radial distances to thereby locate the saw beneath the surfaces of the first and second portions. By positioning the saw blade beneath the surfaces of the first and second portions and by rotating the log, the saw blade is capable of cutting a roll from the log after moving partially through the log. Preferably, the outer surfaces of at least one of the first and second portions maintain the shape of the aperture adjacent to the saw blade during the cutting process. More preferably, the outer surfaces of both the first and second portions maintain the shape of the aperture adjacent to the saw blade during the cutting process.




In some preferred embodiments of the invention, the mandrel is rotatable with the log and includes a third portion connecting the first and second portions. Preferably, the third portion includes an radially outermost surface defining the third radial distance from the longitudinal axis. The saw blade is or can preferably be aligned with the third portion and is movable to the cutting position such that the saw blade is positioned beneath the surfaces of the first and second portions and avoids contact with the third portion as the mandrel rotates with the log. The third portion is preferably a recess that extends around a circumference of the mandrel. In some embodiments, the recess non-abruptly transitions into the first and second portions, such as by having sidewalls that join with the surfaces of the first and second portions at a non-orthogonal angle, by a radiused transitional surface between the sidewalls and the surfaces of the first and second portions, and the like. The transition can preferably reform any partial collapse of the aperture as the log and roll move axially to reposition the log for the next cut or to remove the roll or log from the mandrel. Although a mandrel having a recess extending about the circumference of the mandrel can be rotatable with the log as just described, the mandrel can instead be secured against rotation in cases of logs that can be rotated with respect to the mandrel during cutting operations.




In other preferred embodiments of the invention, the mandrel is secured against rotation, includes a third portion connecting the first and second portions and defining a recess that opens toward the saw blade and that only extends partially around a circumference of the mandrel. The recess can be deeper or shallower than the radius of either or both the first and second portions (i.e., deeper or shallower than the length of the first and/or second radial distances). The saw blade is or can preferably be aligned with the third portion and movable to the cutting position so the saw blade is positioned beneath the surfaces of the first and second portions and does not contact the third portion of the non-rotating mandrel. As with mandrels having a recess extending fully around the mandrel as described above, the third portion preferably non-abruptly transitions into the first and second portions. In addition, the recess preferably non-abruptly transitions into an outermost surface of the third portion joining the first and second portions. The transition can preferably reform any partial collapse of the aperture as the log and roll rotate around the third portion of the mandrel.




More preferably, the third portion is secured against rotation in this embodiment while the first portion is rotatable with the log relative to the third portion. For example, the third portion can be located on a shaft while the first portion can be a sleeve rotatably coupled to the shaft. More preferably, the second portion can also be rotatable and can be an additional sleeve rotatably coupled to the shaft on a side of the third portion opposite the first sleeve.




In other preferred embodiments of the invention, the mandrel includes two or more recesses each having a depth at a corresponding radial distance from the longitudinal axis. Preferably, the mandrel is axially movable to align the blade with the different recesses. Alternatively or in addition, the blade (or saw) can be movable to align the different recesses with the blade. The saw blade is preferably moveable toward the longitudinal axis to a cutting position within any of the recesses. Each cutting position defines a radial position which is preferably shorter than at least one of the first and second radial distances. Preferably, by positioning the saw blade beneath the surfaces of the first and/or second portions in one of the aligned positions and by rotating the log, the saw blade is capable of cutting a roll from the log after moving partially through the log. Also preferably, by axially moving the mandrel to align the saw blade in another position, further cuts can be made in the log in a similar manner.




Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims, and drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is an elevational side view of the saw assembly according to a preferred embodiment of the present invention;





FIG. 2

is an enlarged side view of a mandrel according to a preferred embodiment of the present invention;





FIG. 3

is an enlarged side view of a mandrel according to another preferred embodiment of the present invention;





FIG. 4

is an elevational end view of the saw assembly shown in

FIG. 1

;





FIGS. 5-11

are elevational side views of the saw assembly shown in

FIG. 1

, illustrating the progression of a saw blade and a mandrel of the saw assembly shown in FIG.


1


.











Before one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The use of “consisting of” and variations thereof herein is meant to encompass only the items listed thereafter. The use of letters to identify elements of a method or process is simply for identification and is not meant to indicate that the elements should be performed in a particular order.




DETAILED DESCRIPTION





FIG. 1

illustrates a saw assembly


10


embodying features of the present invention for cutting a log


12


of rolled product into rolls


14


(e.g., rolls sized for consumer use). The log


12


includes a centrally located, longitudinally extending aperture


16


. The saw assembly


10


can include any assembly or mechanism for transporting logs of wound material to the log saw


38


. Such assemblies or mechanisms can include one or more conveyors, carriages, ramps, and the like. In the illustrated preferred embodiment for example, the saw assembly


10


includes a log bucket


18


that feeds the log


12


onto a log indexing conveyor


20


leading to the log saw


38


. The log indexing conveyor can take any form desired, such as one or more belt, chain, tabletop or other types of conveyors. In the illustrated preferred embodiment of

FIG. 1

, the log indexing conveyor


20


includes a log trough


22


that supports the log


12


, although any other shape and arrangement of the conveyor


20


can instead be employed as desired. The conveyor


20


preferably includes a pusher


24


that moves to push the log


12


toward the log saw


38


. The pusher


24


can operate alone to push the log


12


toward the log saw


38


or can work in conjunction with one or more belts, chains, or other conveying elements of the conveyor


20


to perform this function. The pusher


24


(if used) can have a plate, plug, bar, or other element movable to contact and push the log


12


as just described, and can be movable in any conventional manner such as by attachment to a carriage on a rail or track, to a rack and pinion assembly, to a hydraulic or pneumatic cylinder, and the like.




The saw assembly


10


also preferably includes a rotating clamp assembly


28


that receives the log


12


from the pusher


24


(or other log conveyor) and clamps and rotates the log


12


about a longitudinal axis


30


of the log


12


. The illustrated clamp assembly


28


includes two rotating clamps


32


positioned in an end-to-end relationship and defining a gap


34


between the clamps


32


. Alternatively, the log can be rotated by a single clamp


32


located on one side of the log saw blade


40


. In those embodiments having two clamps


32


, the clamps


32


are preferably rotated in tandem by a motor


36


and selectively adjusted to vary the clamping pressure against the log


12


. An example of one such rotating clamp assembly


28


is shown and described in U.S. Pat. No. 5,755,146 which is commonly owned by the assignee of this application. Alternatively, each clamp can be driven be a respective motor as desired, and can provide limited or no clamp pressure adjustability. Although the use of a rotating clamp assembly


28


is preferred, other embodiment employ a clamp assembly that does not rotate, or can instead employ no clamp assembly at all (in which case the rolled product upon the mandrel can be rotated by rotation of the mandrel, by one or more rollers in contact with the rolled product, or in any other manner desired).




The saw assembly


10


includes a saw


38


including a saw blade


40


that defines a plane


42


preferably aligned with the gap


34


between the clamps


32


and that is preferably coupled to an orbital head


44


for rotation about a saw blade axis


46


. Preferably, the orbital head


44


is coupled to a saw base


48


for rotation about a head axis


50


. The saw blade


40


and orbital head


44


are preferably independently driven for rotation by motors (not shown) located within the saw base


48


or otherwise drivably connected to the orbital head. Preferably, the saw blade axis


46


is moved by the orbital head


44


such that the saw blade


40


moves along an arcuate path. By rotating the orbital head


44


, the saw blade


40


translates from a position radially outside of the clamps


32


to a position within the gap


34


between the clamps


32


. In addition, the arcuate motion of the saw blade


40


allows the saw blade


40


to cut multiple logs


12


positioned side by side in different lanes as shown by way of example in FIG.


4


. Although any number of lanes can be utilized with the present invention to increase productivity, the preferred embodiment illustrated in FIGS.


1


and


5


-


11


will be described as a single lane device. Also, in other embodiments of the present invention, different types of saws and cutting devices can be employed as alternatives to the orbital saw of the illustrated preferred embodiment. Such alternative saws and cutting devices include without limitation band saws, wire saws, non-orbital rotating blades, reciprocating blades, and the like, all of which are understood to fall within the terms “saw” and “blade” as referred to herein and in the appended claims.




The saw assembly


10


also includes a mandrel


52


preferably having a first end cantilever mounted to a mandrel support bracket


54


. The mandrel support bracket


54


is preferably coupled to a mandrel conveyor


56


to move the mandrel


52


in a longitudinal direction. Alternatively, the mandrel


52


could be moved longitudinally by any other device known to those skilled in the art for providing linear or substantially linear motion, such as a hydraulic or pneumatic cylinder, a worm or screw drive, a motor driving the mandrel


52


via any conventional power transmission elements or devices, a rack and pinion assembly, a carriage mounted upon a rail or track and to which the mandrel


52


is connected, or other such device. Preferably, the conveyor


56


moves the mandrel


52


toward and away from the clamp assembly


28


. More preferably, the mandrel


52


moves between a position where a recess


58


in the mandrel


52


is located within the clamp assembly


28


and another position where the entire mandrel


52


is outside of the rotating clamp assembly


28


and partially or fully beyond a fixed stripping element


60


.




The stripping element


60


can be a plate, bar, rod, or other element or structure adjacent to the mandrel


52


to strip product (e.g., rolls cut from the log


12


) from the mandrel


52


as the mandrel


52


is moved with respect thereto. In the illustrated preferred embodiment for example, the stripping element is a plate


60


. In other embodiments, the stripping plate or other stripping element


60


can be movable to perform the mandrel stripping process, such as by being connected to any of the elements and structures described above with reference to longitudinal movement of the mandrel


52


.




As mentioned above, the mandrel


52


preferably has a recess


58


. This recess


58


is preferably located at a position between the ends of the mandrel


52


. As used herein and in the appended claims, the term “recess” is not limited to any particular configuration of notch, cutout, void or cavity within the mandrel


52


. Specifically, the recess


58


can be produced in any manner (e.g., machining, casting, forming, molding, and the like) and can take any form that allows the saw blade


40


to move past the outermost surfaces of the portions of the mandrel


52


flanking the recess


58


such that the saw blade


40


can move within the recess


58


to a position that is radially closer to a longitudinal axis


62


of the mandrel


52


than the outermost surfaces of the portions of the mandrel


52


flanking the recess


58


. It should also be noted that the saw blade


40


in this position is also referred to throughout the specification and claims herein as being “beneath” one or more surfaces of the mandrel


52


, although the term “beneath” only refers to the relationship of the saw blade


40


to the mandrel surface(s) and does not indicate or imply an orientation of the mandrel


52


, saw


38


, or other part of the saw assembly


10


with respect to the surrounding environment.




Although some preferred embodiments (such as the illustrated preferred embodiment) employ a mandrel


52


having a round cross-sectional shape, the mandrel


52


can instead be any shape and configuration permitting the mandrel


52


to be positionable within the aperture


16


of the log


12


or roll


14


to assist in maintaining the integrity of the aperture


16


. For example, the cross-section of the mandrel


52


could be triangular-shaped, rectangular shaped, star-shaped, or could have any other shape which provides a contact surface that would at least partially support the log


12


or roll


14


when the mandrel


52


is positioned inside of the aperture


16


. Further, as used throughout the specification and the claims, a “radius” or a “radial distance” is used to identify the distance from the longitudinal axis


62


of the mandrel


52


to any other point at the same or substantially the same longitudinal position along the mandrel


52


, whether or not the cross-sectional shape of the mandrel


52


is round. For example, if the mandrel


52


includes a triangular cross-sectional shape, then the distance between the longitudinal axis


62


and a point defined by one of the apexes of the triangle can be referred to as a radius or a radial distance. Similarly, the distance between the longitudinal axis


62


and a point of the triangle between two apexes of the triangle is also referred to as a radius or radial distance.




Although in the illustrated preferred embodiment the outer periphery of the mandrel


52


preferably has a constant or substantially constant cross-sectional shape between the ends of the mandrel


52


, it should be noted that a non-constant cross-sectional shape is also within the scope of the present invention. For example, the mandrel


52


can taper in one or more directions at any point along the length of the mandrel


52


, can taper intermittently, can have a stepped outer surface along any portion of the mandrel


52


, can have an outer periphery that expands and contracts along the length of the mandrel


52


, or can have any other non-constant longitudinal shape desired.




In some embodiments of the present invention, the saw assembly


10


also includes one or more conveyors positioned or positionable to carry product (e.g., cut product rolls, uncut portions of the log


12


, and the like) away from the saw


38


. Such a conveyor or conveyors can by of any type, including those described above with reference to the log indexing conveyor


20


. Also, in some embodiments one or more of such conveyors can be moved to and from a position to receive product from the mandrel


52


. By way of example only, the illustrated preferred embodiment shown in

FIG. 1

has a movable conveyor


64


and a product discharge conveyor


66


positioned side by side with each other. The movable conveyor


64


preferably includes a rotatable belt


68


which is coupled to actuators


70


that move the belt


68


toward and away from the mandrel


52


. Any other conventional system or device can instead be employed to move the rotatable belt


68


toward and away from the mandrel


52


. The product discharge conveyor


66


preferably includes a rotating belt


72


positioned to receive product from the movable conveyor


64


and to convey the product out of the saw assembly


10


.





FIG. 2

illustrates the mandrel


52


according to one preferred embodiment of the invention. The mandrel


52


includes a central shaft


74


that is preferably mounted at one end to the mandrel support bracket


54


and that is secured against rotation. The central shaft


74


can be solid or hollow, and preferably includes a pointed tip


76


at the distal end and a non-rotating portion


78


between the ends of the mandrel


52


including the recess


58


. The pointed tip


76


can assist in proper mating of the mandrel


52


with a log


12


as mentioned above, although other tip shapes can also be employed to perform this function, such as bull-nosed or rounded tip shapes. In still other embodiments, the end of the mandrel has no tapered or rounded tip.




In order to enable product on the mandrel


52


to rotate with respect to the mandrel


52


during cutting operations upon the log


12


, bearings


80


are preferably coupled to the central shaft


74


on one side of the non-rotating portion


78


to rotatably support a main sleeve


82


over the central shaft


74


. Preferably, other bearings


84


are also coupled to the central shaft


74


on the other side of the non-rotating portion


78


opposite the main sleeve


82


to rotatably support an additional sleeve


86


over the shaft


74


between the bearings


84


. The bearings


80


,


84


can be of any conventional form, such as thrust bearings, ball bearings, roller bearings, journal bearings, and the like. Although bearings


80


,


84


and sleeves


82


,


86


are preferably employed on both sides of the recess


58


, in some embodiments a bearing


80


,


84


and/or sleeve is located only on one side of the recess


58


. In other embodiments (such as those in which the log


12


and mandrel


52


have a clearance fit), no bearings are employed upon the mandrel


52


. Instead, the log


12


contacts and is rotatable about the stationary shaft


74


or is received upon sleeves


82


,


86


which have a sufficiently clear fit to rotate upon the stationary shaft


74


.




With reference again to the embodiment of the mandrel


52


illustrated in

FIG. 2

, the radii of the radially outermost surfaces of the sleeves


82


,


86


and the radius of the radially outermost portion of the non-rotating portion


78


are preferably substantially equal, although differences in the radii are possible in some embodiments. With reference to

FIG. 1

, the saw assembly


10


preferably includes a motor


88


that rotates the main sleeve


82


about the central shaft


74


to rotate with the log


12


during the cutting process. As shown in

FIG. 2

, the recess


58


extends only partially around the mandrel


52


, leaving a side of the non-rotating portion


78


unrecessed. Preferably, the recess


58


of the non-rotating portion


78


circumferentially transitions in a non-abrupt manner into the unrecessed part of the non-rotating portion


78


. Also, the recess


58


preferably non-abruptly transitions into the sections of the non-rotating portion


78


flanking the recess


58


along the longitudinal axis


62


. The non-abrupt transitions of the non-rotating portion can be defined in a number of different manners, such as surfaces of the recess that are at an acute angle with respect to the recess


58


as shown in

FIG. 2

, can be defined by curved or bowed walls of the recess


58


, and the like.




The present invention is not limited to the preferred mandrel


52


described above and illustrated in FIG.


2


. For example, and as described in greater detail above, the mandrel


52


could be entirely secured from rotation so that the recess


58


would always face the saw blade


40


and the log


12


and cut rolls


14


would slidably contact the mandrel during rotation and translation of the log


12


and rolls


14


relative to the mandrel


52


. In other embodiments, the entire mandrel rotates such as the embodiment illustrated in FIG.


3


. With reference to

FIG. 3

, the mandrel


152


includes a shaft


174


that is mounted at one end to the mandrel support bracket


54


. The mandrel


152


includes a pointed tip


176


at the distal end of the mandrel


152


to aid in positioning the mandrel


152


within the aperture


16


of the log


12


, although other mandrel end shapes can be employed as described in greater detail above. The mandrel


152


includes a recess


158


that extends entirely around the mandrel


152


. Preferably, the recess


158


non-abruptly transitions into the first and second portions P


1


, P


2


of the mandrel


152


flanking the recess


158


, which defines a third portion P


3


. Also shown in

FIG. 3

, the first portion P


1


includes a radially outermost surface defining a first radial distance d


1


from the longitudinal axis


62


, the second portion P


2


includes a radially outermost surface defining a second radial distance d


2


from the longitudinal axis


62


, the saw blade


40


(illustrated in the cutting position) defines a third radial distance d


3


between the saw blade


40


and the longitudinal axis


62


, and the third portion P


3


includes a radially innermost surface defining a fourth radial distance d


4


from the longitudinal axis


62


.




The operation of a preferred embodiment of the saw assembly according to the present invention is described with reference to

FIGS. 5-11

. As shown in

FIG. 5

, the log


12


is shown in the log bucket


18


ready to be loaded into the log indexing conveyor


20


.




With reference to

FIG. 6

, the log bucket


18


drops the log


12


into the log indexing conveyor


20


, and the pusher


24


moves the log


12


toward the clamp assembly


28


. Preferably, the mandrel


52


moves simultaneously toward the clamp assembly


28


. The orbital head


44


maintains the saw blade


40


away from the rotating clamp assembly


28


.




As shown in

FIG. 7

, the mandrel


52


enters the rotating clamp assembly


28


and aligns the recess


58


with the plane


42


of the saw blade


40


and the gap


34


between the rotating clamps


32


. Preferably, the pusher


24


moves the log


12


into the rotating clamp assembly


28


, positioning the mandrel


52


within the aperture


16


of the log


12


. The motor


36


rotates the clamps


32


and the motor


88


rotates the main sleeve


82


to rotate the main sleeve


82


with the log


12


. The orbit head


44


moves the saw blade


40


down through the gap


34


between the clamps


32


and into the recess


58


of the mandrel


52


to cut a roll


14


from the rotating log


12


.




With additional reference to

FIG. 2

, the saw blade


40


preferably remains in the recess


58


as the log


12


is rotated to ensure that the roll


14


is completely cut from the log


12


. The portions of the mandrel


52


flanking the recess


58


maintain the integrity of the aperture


16


during the cutting operation. The small amount of paper that might deflect into the recess


58


due to the pressure generated by the saw blade


40


can be reformed to its original position as the log


12


and roll


14


rotate around to the bottom of the non-rotating portion


78


of the mandrel


52


where the recess


58


is not present. By virtue of the configuration of the recess


58


, the flanking portions of the mandrel


52


reduces the deflection of the aperture


16


by supporting the aperture


16


on both sides of the saw blade


40


and then by reforming the aperture


16


as the log


12


and roll


14


rotate around the non-rotating portion


78


of the mandrel


52


. The use of a non-abrupt transition between the recess


58


and the portion of the mandrel


52


on the opposite side of the mandrel


52


is effective at gently reforming the deflected paper outwardly to the shape of the aperture


16


as the log


12


and roll


14


rotate around the non-rotating portion


78


. As an alternative, other types of transitions between the recess


58


and the unrecessed opposite side of the non-rotating portion can be employed to achieve the same results. Also, the transition (preferably non-abrupt) between the recess


58


and the portion of the mandrel


52


flanking the recess


58


can gently reform the deflected paper outwardly to the shape of the aperture


16


when the log


12


and the roll


14


are advanced by the pusher


24


farther up the mandrel


52


.




In other embodiments of the present invention such as that shown in

FIG. 3

, the mandrel


152


(and more specifically, the portions of the mandrel


152


adjacent to the recess


158


) does not reform the aperture


16


during rotation of the mandrel


152


. Instead, the mandrel


152


reforms the aperture


16


when the pusher


24


moves the log


12


and roll


14


farther onto the mandrel


152


. Specifically, the non-abrupt transition


160


between the radially innermost surface of the third portion P


3


and the outer surface of the first portion P


1


reforms the deflected paper outwardly to the shape of the aperture


16


when the log


12


and the roll


14


are advanced by the pusher


24


farther up the mandrel


152


.




After the roll


14


is cut, the orbital head


44


preferably moves the saw blade


40


away from the rotating clamp assembly


28


so that the pusher


24


can move the log


12


and roll


14


toward the mandrel


52


a distance equal to the length of the next roll


14


to be cut, which typically remains consistent for the entire log


12


. Eventually, the cut roll


14


is pushed out of the rotating clamp assembly


28


and slides farther onto the mandrel


52


. In the illustrated preferred embodiment, the mandrel


52


is secured against axial movement to maintain the recess


58


in alignment with the plane


42


of the saw blade


40


.




Referring to

FIG. 8

, the saw assembly


10


has cut most of the log


12


into consumer-sized products Each cut roll


14


is pushed by the pusher


24


to slide farther up the mandrel


52


, forming a row


90


of cut rolls


14


. After the last roll


14


is cut from the log


12


as shown in

FIG. 9

, the orbital head


44


preferably moves the saw blade


40


away from the rotating clamp assembly


28


. Preferably, the pusher


24


moves the uncut remainder of the log


12


through the rotating clamp assembly


28


and onto the mandrel


52


.




In

FIG. 10

, the actuators


70


of the movable conveyor


64


raise the belt


68


toward the mandrel


52


to a position adjacent to the cut rolls


14


on the mandrel


52


. Preferably, the mandrel conveyor


56


moves the mandrel


52


away from the rotating clamp assembly


28


to cause the first cut roll


14


to contact the stripper plate


60


. The stripper plate


60


pushes the rolls


14


off of the mandrel


52


and onto the belt


68


as the mandrel conveyor


56


continues to move the mandrel


52


away from the rotating clamp assembly


28


. As shown in

FIG. 11

, the mandrel


52


moves to completely remove the rolls


14


from the mandrel


52


and the pusher


24


returns to the starting position away from the rotating clamp assembly


28


. The cycle is completed when the actuators


70


lower the belt


68


supporting the cut rolls


14


to align the belt


68


with the belt


72


of the product discharge conveyor


66


such that rotation of the belts


68


,


72


moves the cut rolls


14


to downstream operations (such as to a packaging machine or equipment).




In another method of using the log saw assembly


10


according to the present invention, a mandrel (such as a winding mandrel (not shown)) similar to the mandrel


52


described above is left within the log


12


and is loaded into the log indexing conveyor


20


. In this case, the log


12


and the winding mandrel could be gripped on the end opposite to the rotating clamp assembly


28


such that a recess


58


of the winding mandrel can be aligned with the plane


42


of the saw blade


40


. Preferably, the pusher


24


would then index the log


12


into the rotating clamp assembly


28


while the winding mandrel remains stationary to thereby index the cut rolls


14


off of the winding mandrel and onto a conveyor similar to the movable conveyor


64


or the product discharge conveyor


66


.




In an additional embodiment of the invention, the mandrel


52


includes multiple recesses


58


and is movable to selectively align each of the multiple recesses


58


with the plane


42


of the saw blade


40


. The mandrel


52


could be used in a similar manner to that described above, except that the mandrel


52


would begin positioned within the log


12


and would preferably index with the log


12


to align sequential recesses


58


with the saw blade


40


to cut the next roll


14


from the log


12


. Alternatively, the mandrel


52


could be used with a saw


38


that includes multiple saw blades


40


and additional clamp assemblies


28


. The saw blades


40


are preferably coupled together and are offset from each other along the saw blade axis


46


, and the additional clamp assemblies


28


(rotatable or non-rotatable) are preferably positioned in an end-to-end relationship with the other clamp assemblies


28


. Each saw blade


40


will move between a gap


34


between adjacent clamps


32


and into a respective recess


58


. In this manner, the pusher


24


could index the log


12


at larger increments because each pass of the saw blades


40


will make more cuts through the log


12


.




Accordingly, a mandrel


52


having one or more recesses


58


according to the present invention can be stationary to receive moving rolled product pushed thereon, can be movable to be inserted within rolled product that is simultaneously moved with respect to the mandrel


52


, or can be movable to be inserted within stationary or substantially stationary rolled product. In the case where both the mandrel


52


and the rolled product are movable, the mandrel and rolled product can be moved in stages, simultaneously, or in any other manner desired. In any case, rolled product is preferably cut as described above as it is placed upon the mandrel


52


as it is removed from the mandrel


52


, or between these operations.




The embodiments described above and illustrated in the drawings are presented by way of example only and are not intended as a limitation upon the concepts and principles of the present invention. As such, it will be appreciated by one having ordinary skill in the art, that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention as set forth in the appended claims.



Claims
  • 1. A saw assembly for cutting a rotating log into rolls, the saw assembly comprising:a mandrel positionable to at least partially support the rotating log, the mandrel including a longitudinal axis, a first portion including a radially outermost surface defining a first radial distance from the longitudinal axis, and a second portion including a radially outermost surface defining a second radial distance from the longitudinal axis; and a saw blade movable toward the longitudinal axis to a cutting position between the first portion and the second portion, the cutting position defining a third radial distance between the saw blade and the longitudinal axis, the third radial distance being shorter than each of the first and second radial distances, wherein the mandrel includes a third portion connecting the first and second portions, the third portion including a radially innermost surface defining a fourth radial distance from the longitudinal axis, the fourth radial distance being shorter than each of the first, second, and third radial distances, and wherein the mandrel includes a sloped wall between the radially innermost surface of the third portion and the radially outermost surface of the first portion.
  • 2. The saw assembly of claim 1, wherein the first and second radial distances are substantially the same.
  • 3. The saw assembly of claim 1, further comprising:a log saw clamp adapted to rotate the log, the log saw clamp at least partially surrounding at least one of the first portion and the second portion.
  • 4. The saw assembly of claim 1, wherein the mandrel is rotatable.
  • 5. The saw assembly of claim 1, wherein the radially innermost surface of the third portion is connected to the radially outermost surface of the first portion by the sloped wall defining an acute included angle with respect to the longitudinal axis.
  • 6. The saw assembly of claim 1, wherein the mandrel is non-rotatable.
  • 7. The saw assembly of claim 1, wherein the third portion is non-rotatable.
  • 8. The saw assembly of claim 7, wherein the second portion is rotatable.
  • 9. A method for cutting a rotating log into rolls, the method comprising:providing a mandrel including a longitudinal axis, a first portion including a radially outermost surface defining a first radial distance from the longitudinal axis, and a second portion including a radially outermost surface defining a second radial distance from the longitudinal axis; at least partially supporting the log with the mandrel received within an aperture of the log; rotating the log; moving the saw blade toward the longitudinal axis to a cutting position between the first portion and the second portion, the cutting position defining a third radial distance between the saw blade and the longitudinal axis, the third radial distance being shorter than each of the first and second radial distances, wherein the mandrel has a third portion connecting the first and second portions, the third portion including a radially innermost surface defining a fourth radial distance from the longitudinal axis, the fourth radial distance being shorter than the each of the first, second, and third radial distances, and wherein the mandrel includes a sloped wall between the radially innermost surface of the third portion and the radially outermost surface of the first portion; cutting at least one roll from the log as the saw blade moves to the cutting position, the at least one roll including an aperture; moving the at least one roll along the mandrel in the longitudinal direction; and reforming the aperture of the roll with the sloped wall as the roll is moved in the longitudinal direction.
  • 10. The method of claim 9, further comprising clamping the log within a log saw clamp, wherein rotating the log includes rotating the log saw clamp and the log.
  • 11. The method of claim 9, further comprising rotating the mandrel.
  • 12. The method of claim 9, further comprising securing the mandrel against rotation.
  • 13. The method of claim 9, further comprising securing the third portion of the mandrel against rotation, and rotating the first portion of the mandrel with the log.
  • 14. The method of claim 13, further comprising rotating the second portion of the mandrel with the log.
  • 15. A saw assembly for cutting a rotating log into rolls, the log and the rolls each having a centrally located, longitudinally extending aperture, the saw assembly comprising:a movable saw blade; a mandrel adapted to be received within the aperture of the log, the mandrel including a non-rotating portion having a recess opening in one direction and an unrecessed part opposite to the recess, the saw blade movable from a first position in which the saw blade is located outside of the recess in the mandrel to a second position in which the saw blade is located within the recess, wherein the non-rotating portion includes a non-abrupt circumferential transition between the recess and the unrecessed part of the non-rotating portion, and wherein the mandrel includes a sloped wall between the recess and an outer surface of the mandrel flanking the recess.
  • 16. The saw assembly of claim 15, further comprising a log saw clamp adapted to rotate the log, the log saw clamp at least partially surrounding a portion of the mandrel.
  • 17. The saw assembly of claim 15, wherein the mandrel is non-rotatable.
  • 18. The saw assembly of claim 17, wherein the recess extends partially around the mandrel, the recess opening toward the saw blade.
  • 19. The saw assembly of claim 15, wherein the mandrel includes at least one rotatable portion adjacent to the non-rotating portion.
  • 20. The saw assembly of claim 19, wherein the non-rotatable portion is located on a shaft and the rotatable portion includes a sleeve rotatably coupled to the shaft.
  • 21. The saw assembly of claim 19, wherein the mandrel includes an additional rotatable portion on a side of the non-rotatable portion opposite to the rotatable portion.
  • 22. A method for cutting a rotating log into rolls, the method comprising:receiving a mandrel within a centrally located, longitudinally extending aperture in the log; rotating the log; moving a saw into and within a recess of a non-rotating part of the mandrel; cutting at least one roll from the log as the saw blade moves to the cutting position, the at least one roll including an aperture; rotating the at least one roll about the mandrel; reforming the aperture of the roll with a non-abrupt circumferential transition between the recess and an unrecessed part of the non-rotating portion as the roll rotates about the mandrel; moving the at least one roll along the mandrel in the longitudinal direction; and reforming the aperture of the roll with a sloped wall between the recess and an outer surface of the mandrel flanking the recess as the roll is moved in the longitudinal direction.
  • 23. The method of claim 22, further comprising clamping the log within a log saw clamp, wherein rotating the log includes rotating the log saw clamp and the log.
  • 24. The method of claim 22, further comprising securing the mandrel against rotation.
  • 25. The method of claim 22, further comprising rotating a rotatable portion of the mandrel with the log, the rotatable portion being adjacent to the non-rotatable portion.
  • 26. The method of claim 25, further comprising rotating an additional rotatable portion of the mandrel with the log, the additional rotatable portion being on a side of the non-rotatable portion opposite to the rotatable portion.
  • 27. A log saw mandrel for use with a log saw having a log saw blade, the log saw mandrel comprising:an elongated body having a first end, a second end opposite the first end, and an outer surface extending between the first and second ends; a recess defined in the elongated body between the first and second ends of the elongated body, the recess extending partially through the elongated body and shaped to receive at least part of the blade of the log saw beneath the outer surface of the elongated body; and a sloped wall between the recess and an outer surface of the elongated body flanking the recess.
  • 28. A method of cutting a log of wound product, comprising:receiving at least part of the log upon a mandrel; cutting at least one roll from the log with a log saw blade at a location along the mandrel, the at least one roll including an aperture; and receiving at least part of the log saw blade within a recess in the mandrel; moving the at least one roll along the mandrel in a longitudinal direction; and reforming the aperture of the roll with a sloped wall between the recess and an outer surface of the mandrel flanking the recess as the roll is moved in the longitudinal direction.
US Referenced Citations (9)
Number Name Date Kind
460317 Whitney Sep 1891 A
811593 Stout Feb 1906 A
1042998 Blackmore Oct 1912 A
1242448 Judelshon Oct 1917 A
1984730 Darling Dec 1934 A
4487378 Kobayashi Dec 1984 A
5271137 Schutz Dec 1993 A
5453070 Moody Sep 1995 A
5755146 Lumberg May 1998 A