Patent Publication Number: US-11020870-B2

Title: Apparatus for slabbing rolls of tissue

Description:
CROSS-REFERENCE 
     The present patent application is based upon and claims the benefit of provisional patent no. 62/753,248, filed Oct. 31, 2018. 
    
    
     BACKGROUND OF THE INVENTION 
     When manufacturing paper products, large rolls of tissue paper are provided for processing into various products such as bath tissue, paper towels, air dried, and crepe air dried materials such as napkins. The rolls of tissue are provided on cores and may weigh up to 8,000 pounds. The tissue is rolled on the core and may be 90 inches in diameter. Paper manufacturers receive these rolls and unwind them to process the tissue paper into the various products being manufactured. Problems are sometimes encountered with the rolls of tissue in that the tissue may be too thin or too thick and cannot be processed on the converting operations downline. The paper mill does not want to waste the tissue or fiber on the problematic roll and wishes to reclaim that tissue and fiber for remanufacturing and rewinding into usable material. If the roll is a fresh roll it is called a parent roll. If the roll is left-over scrap it may be commonly referred to as a broke roll. A broke roll may be also designated because there is an imperfection in the material grade of the tissue or an issue with the actual manufacturing process that requires the product to be designated as non-usable. It is desirable to reclaim fiber from the broke material. Reclaiming the fiber allows it to be converted back into a fresh roll of usable material. 
     Efforts to reclaim material from a broke roll for reprocessing have included operator intervention wherein the operators use sharp knives to specifically slice the damaged material off of the core. This process creates safety hazards for the users. 
     Another commonly used method to remove broke material makes use of a machine called a guillotine which will chop rolls with brute force. The guillotine chops the roll in half, destroying the paper tissue and the core. The core material gets intermixed with the paper tissue and will have to be separated manually before the paper tissue can be recycled for reprocessing. Further, the use of a guillotine is undesirable because it destroys the core. Cores are generally very expensive in the manufacturing process and most manufacturers wish to preserve the cores for reuse. The guillotine unacceptably destroys the core, makes the broke tissue removed from the core impure, and involves added labor. This process creates safety hazards for the users. 
     There is a need for effectively cleaning damaged tissue off of broke rolls without damaging the core. 
     There is a further need for effectively cleaning damaged tissue off of cores without additional operator labor. 
     There is an additional need for cleaning fiber of damaged tissue off of broke rolls without threatening operator safety. 
     Finally, there is a need to remove the tissue from rolls of various sizes and to be able to measure the amount of material being cut off and to control the amount of material being cut off based on the weight of the product, diameter of the roll, material type and other parameters. 
     SUMMARY OF THE INVENTION 
     The slabbing apparatus of the present invention is an automated machine capable of profiling a roll of tissue material by determining the diameter, circumference, and weight of the roll. The apparatus calculates the amount of material to be removed based on operator input and determined parameters of weight, diameter, and density. The apparatus includes a hoist and at least one weight measurement sensor  70  which determines the weight of the roll and helps position the roll so that the cut and removed material will fall to a desired location. The present invention will be able to slab narrow slit rolls, long width rolls, and various width rolls in between. It is able to measure the amount of material being cut off and to control the amount of material being cut off based on the weight of the product, diameter, material type, and information received from load cells located on the hoist. The invention further includes a torque sensor  60  on the cutting blade to determine variations in the condition of the tissue being cut and removed and automatically stopping the cutting action if the torque falls outside of an acceptable parameter. The apparatus of this invention will use chucks that are conical shaped in order to accommodate variations in core size when engaging and lifting the core. The invention can also be used with a core cleaner or core joiner for removing all material left on cores and repairing clean cores for further use. 
     The present invention can be used with various options such as core clamps, expanding chucks, take away conveyers, accumulation tables, and pulp making machines. 
     This invention will reclaim fiber from a broke roll or a damaged parent roll. This reclaimed fiber can be used and converted back into a fresh roll of usable material. Paper mills manufacture these rolls in batches. When one parent roll ends up unusable because the tissue may be too thin or too thick making it unable to be processed on the downstream converting operations, the entire batch of rolls may need to be reprocessed. The present invention is designed to assist with this reprocessing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the apparatus of the present invention. 
         FIG. 2  is a side elevation view of the apparatus of  FIG. 1 . 
         FIG. 3  is a segmented view taken along lines  3 - 3  of  FIG. 2 . 
         FIG. 4  is a segmented view taken along lines  4 - 4  of  FIG. 1 . 
         FIG. 5  is an alternative embodiment of the apparatus shown in  FIG. 4 , with the hold down apparatus removed. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention includes a frame  10  that is commonly positioned proximate a conveyer. The frame  10  supports a carriage  12  that carries a hoist  14 . The carriage  12  is movable on the frame  10 , allowing it to position itself with regard to a roll of tissue. The hoist  14  will engage the roll with conically shaped chucks  16  and lift the roll off of the surface of the conveyer. The carriage  12  will then move along the frame  10  to a position proximate a location where pulp is designated for removal. Sometimes a pulp catcher is used; other times removed pulp may drop onto a conveyer for transport to a pulping machine. 
     The frame includes rails  20  posited across the topside of the frame. The carriage  12  rides on the rails  20  and is driven on the rails by drive wheels  22 . The drive wheels are powered by a carriage drive motor  27  engaged with a drive shaft  26  supported by bearings  28 . 
     The hoist  14  is supported on the carriage  12  and moves vertically with regard to the carriage  12  on hoist rails  30 . Hoist drive motor  32  is engaged with the hoist drive shaft  34 . The hoist drive motor  32  will power the hoist  14  vertically, allowing the hoist  14  to lower and engage with rolls and raise to remove the rolls from contact with the conveyer. The hoist  14  further includes drive motors  36  for rotating the chucks  16  engaged with the roll so that the roll is indexed and positioned with respect to a cutting blade  38 . The cutting blade  38  is engaged with the hoist  14  by a support frame  40 . The cutting blade  38  is attached on the end of an arm  42  carried by the support frame  40 . The arm  42  carries a drive motor  44  for powering the cutting blade  38  to cut the tissue from the roll. The drive motor  44  includes a sensor for measuring the amount of torque needed to power the cutting blade  38 . If the torque falls outside of preset parameters, the cutting blade  38  is turned off to prevent damage to the cutting blade and roll of material. The cutting arm  42  has a drive motor  46  which enables the cutting blades  38  to be positioned and adjusted to varying diameters of rolls of tissue. The support frame  40 , cutting arm  42 , and cutting blade  38  are movable horizontally along the hoist  14 , preferably by means of a timing belt (not shown). This allows for the cutting blade  38  to be moved along the entire width of the roll being processed. 
     The present invention further includes a hold down apparatus  18 . The hold down apparatus  18  includes a roller  48  which engages with the surface of the roll of material and measures the amount of material being removed from the roll. The roller  48  is carried by an arm  50  which in turn is carried by support arm  52 . Support arm  52  is engaged with support arm drive roller  54  which rotates the hold down apparatus  18 , placing the hold down roller  48  into engagement with the surface of the roll of tissue. Piston  56  is engaged between support arm  52  and arm  50  and helps ensure that the roller  48  stays engaged with the surface of the roll of tissue. 
     The entire apparatus is controlled by a PLC with minimal operator input. 
     In operation, the apparatus of the present invention will position itself proximate a roll to be processed. The roll will be measured with sensors to create a roll profile. The roll profile will indicate the roll size, length, diameter, and weight. A sensor  80  is used to measure the diameter. The PLC will use these measurements to determine the amount of material to be cut off and control the amount of material being cut off based upon the weight of the product, diameter, material type, and further information. 
     Many of the rolls being processed are non-standard shapes: for instance, pear shaped, egg shaped, etc. The roll profile information will determine how the roll is cut. The roll being cut is based upon operator input. The operator will input pounds per cut. A jumbo roll or parent roll can weigh up to 8,000 pounds. A typical batch of pulp is limited to around 3,000 pounds for transportation to a pulping machine. Knowing the diameter and circumference of the roll, and the general density of the material, the machine calculates the depth of material to be cut off with a single cutting action and sending of the cut off material to the pulp machine. As the diameter of the roll being processed gets smaller, the roll will rotate and drop the cut off material to a specific location. Knowing the blade location and based on the cutting tolerance, the entire unit can be moved to efficiently drop the removed material into small spaces. Finally, the drives of this apparatus include torque control, which will be able to monitor the actual slabbing of the roll. If for some reason the torque on the cutting tool dramatically increases, the cutting can be stopped, and the operator can inspect the roll to determine the cause for the increase in torque. This helps to prevent damage to the equipment. 
     The above detailed description of the present invention is given for explanatory purposes. It will be apparent to those skilled in the art that numerous changes and modifications can be made without departing from the scope of the invention. Accordingly, the whole of the foregoing description is to be construed in an illustrative and not a limitative sense, the scope of the invention being defined solely by the appended claims.