Patent Publication Number: US-8534173-B2

Title: Paper pushing device

Description:
FIELD 
     The present teachings relate to the field of paperboard processing, and more particularly to a device, system, and method for pushing paperboard, or other sheet-like stock out of a press, die, punch, stripping station, blanking station, or other paperboard manipulating apparatus. 
     BACKGROUND 
     Packaging, stationary, and other paper-based products are generally manufactured using sheets of paperboard or other raw paper stock that is drawn across a press, die, punch, stripping station, blanking station, or other paperboard manipulating equipment. Cartons, containers, playing cards, signs, placards, corrugated boxes, and other paperboard products are generally formed by contacting the stock with a punch or die. The methods can comprise contacting the stock with a cutting or creasing blade to generate blanks out of the sheet. 
     A first process of stripping out holes or sections from a larger piece of stock is generally referred to as stripping. Stripping leaves a shaped hole and a desired perimeter or outline in the otherwise intact stock paperboard. Subsequently, a second process of cutting or punching a desired shape or section of the stock entirely out of the stock, dropping, and collecting the removed portion, is generally referred to as blanking. In both stripping and blanking operations, the paperboard, cardboard, plastic, fibrous, or other material, is conveyed over a working area. The working area can generally include a flat cutting surface or a hollow female blanking area over which a blank piece of stock can be contacted with a blade, punch, or other working tool. The paperboard or stock is conveyed through such work stations on support frames, for example, on wooden, metal, paddled, or other support frames, which can be sized to conform to the size of the blank stock. The sheets can be conveyed across the stripping or blanking stations using conveyor belts, belt drives, linear motors, or other sources of mechanical driving force. 
     Known stripping and blanking configurations suffer from a number of drawbacks. During a stripping operation, a paperboard stock is cut and/or creased into a desired form. The cut stock can be perforated such that the desired product remains attached to the surrounding paperboard skeleton. During a stripping operation, the paperboard stock can become stuck or lodged in the die as the die is retracted from the work station. Also, during a stripping operation, the surrounding paperboard skeleton can become stuck in the stripper. 
     Similarly, during blanking operations, a blanking press can cause pressure on a paperboard stock such that a desired product can be removed from the surrounding paperboard skeleton. When the blanking press is retracted from the work station, a vacuum can be created between the blanking press and the product blank, thereby causing the paperboard skeleton product to become stuck in the blanking unit. Resulting jams and hang-ups in the material supply path and incomplete or faulty stripping and/or blanking operations can require valuable operator time and effort to fix. These errors can also cause lost costs due to manufacturing downtime, and can result in a loss of potentially recoverable material. A need exists to eliminate these and other drawbacks in the art. 
     SUMMARY 
     In some embodiments, the present teachings relate to a paper pushing device that comprises a shaft configured to be received in an opening of a retaining board. The shaft can comprise a central axis, a distal end, and a support end opposite the distal end. 
     According to various embodiments, in addition to the shaft, the paper pushing device can comprise a base, a shoulder extending upward from the base, and a paddle connected to the shoulder. In some embodiments, the base, shoulder, and paddle can be considered part of an arm and the device can comprise the arm connected to the shaft. 
     The base can have opposing first and second ends. The first end can intersect with the support end of the shaft at an intersection. The base can comprise a first thickness. The base can extend in a first direction perpendicular to the shaft and away from the central axis of the shaft. The paddle can extend in a second direction opposite the first direction and extend past the central axis of the shaft. 
     According to various embodiments, the paddle can comprise a lower first section and an elevated second section. The elevated second section can extend upwardly from the lower first section at an angle of from about 110° to about 160°. The paddle can comprise a second thickness that is greater than the first thickness of the base. 
     According to various embodiments, the shaft can comprise a diameter that is at least half the width of the base. The shaft can comprise one or more splines protruding from an outer surface of the shaft to secure the shaft in the retaining board. The shaft can comprise one or more annular sections in addition to or instead of the one or more splines. In some embodiments, the shaft can comprise a plurality of annular sections, wherein the annular sections are spaced apart from one another. Each annular section can extend radially outwardly from the shaft and can comprise an outer diameter that is greater than the minimum diameter of the shaft. 
     In some embodiments, the present teachings relate to a system comprising a paper pushing device as described herein and a retaining board that can comprise an operational surface. The retaining board can comprise an opening disposed in the operational surface, for example, a hole, a recess, a well, a through hole, or the like. The shaft of the paper pushing device can be disposed in the opening, for example, to anchor the device in the retaining board. The retaining board can comprise a thickness, and in some embodiments the opening can comprise at least one through hole that extends all the way through the thickness of the retaining board. In some embodiments, the opening can comprise a hole that does not extend all the way through the retaining board such that the opening comprises a bottom. The opening can have a diameter that matches the outer diameter of the shaft, or that is just slightly larger than the outer diameter of the shaft such that the shaft snugly fits within the opening. If the shaft is provided with annular sections the opening can have a diameter that is the same as or only slightly larger than the outer diameter of the annular sections. 
     According to various embodiments, the retaining board can comprise one or more die rule slots disposed in the operational surface. The die rule slots can be configured to receive a die rule. The retaining board can comprise one or more die lock retaining slots disposed in the operational surface. The die lock retaining slots can intersect with one or more die rule slots. The die lock retaining slots can be configured to receive a die lock. One or more die locks disposed in one or more respective die lock retaining slots can be used to lock one or more die rules in the one or more die rule retaining slots. For example, die rules, die locks, retaining boards, adjustment systems, and methods that can be used according to various embodiments include those shown and described in U.S. Pat. Nos. 6,779,426; 5,730,039; RE 35,522; 5,582,102; 5,333,519; 5,211,084; 5,197,367; 5,140,872; 5,029,505; and 4,850,950; each of which is incorporated herein in its entirety by reference. 
     In some embodiments, the present teachings relate to a method of processing a workpiece. The method can comprise manipulating a workpiece in at least one station. The at least one station can comprise a die cutting station, a rotary die cutting station, a burst cutting station, a stripping station, a blanking station, an embossing station, a printing station, or the like. The station can be used to form a manipulated workpiece, for example, a manipulated paperboard blank. The method can comprise expelling the workpiece from the at least one station by using a paper pushing device according to the present teachings. The paper pushing device can comprise a shaft configured to be received in the opening of a retaining board and the paper pushing device can comprise an arm connected to the shaft. The paper pushing device can comprise an arm extending from the shaft. The arm can comprise a planar base connected to the shaft and extending in a first direction, a shoulder extending upwardly from the planar base, and a paddle connected to the shoulder and extending in a second direction that is opposite the first direction. The workpiece can comprise any type of material that can be manipulated by a stripping station, a blanking station, an embossing station, a printing station or the like, for example, the workpiece can comprise a paperboard stock. 
     These and other embodiments of the present teachings will be more fully understood with reference to the drawings appended hereto and the detailed description set forth below. The specific embodiments described herein are exemplary only and are not to be construed as limiting. Various modifications, substitutions, deletions, and other changes can be made, as would be understood by those skilled in the art, without departing from the present teachings. 
    
    
     
       DRAWINGS 
       The present teachings will be described with reference to the accompanying drawings, in which like elements are referenced with like numbers. 
         FIG. 1  is a side perspective view of a paper pushing device according to various embodiments of the present teachings. 
         FIG. 2  is a side view of the paper pushing device shown in  FIG. 1 . 
         FIG. 3  is a bottom view of the paper pushing device shown in  FIG. 1 . 
         FIG. 4  is front view of the paper pushing device shown in  FIG. 1 . 
         FIG. 5  is an end view of the paper pushing device shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     According to various embodiments of the present teachings, a paper pushing device is provided that can be configured to contact paperboard or other stock, for example, that comprises fibrous material, paper, plastic, film, a web, or cardboard. In some embodiments, the stock can comprise any product capable of being manipulated by a die cutting press. The paper pushing device can comprise a shaft that can be configured to be received and anchored in an opening in a retaining board, for example, as described in U.S. patent application Ser. No. 12/426,699, which is incorporated herein in its entirety by reference. The shaft can have a central axis. The paper pushing device can comprise an arm connected to the shaft. The arm can comprise a base, a shoulder extending upward from the base, and a paddle connected to the shoulder. The base can comprise opposing first and second ends. The first end of the base can connect and intersect with the support end of the shaft at an intersection. The base can be planar and comprise a first thickness. The base can extend in a first direction perpendicular to the shaft and away from the central axis of the shaft. The shoulder can extend upwardly from the second end of the base and connect to the paddle. The paddle can extend in a second direction opposite the first direction and past the central axis of the shaft. The paddle can comprise a lower first section and an elevated second section, the elevated second section can extend upwardly from the lower first section and can be angled with respect to the lower first section at an angle of from about 110° to about 160° relative to the lower first section, for example, at an angle of from about 120° to about 150°, or from about 125° to about 145°, or from about 130° to about 140°. The paddle can comprise an upper contact surface and a lower undersurface. The upper contact surface of the paddle can contact a workpiece. The paddle can have a width that widens as it approaches a distal edge. 
     According to various embodiments, the paper pushing device can be used in combination with a retaining board to form a system or station. The station can comprise, for example, a die cutting station, a rotary die cutting station, a burst cutting station, a blanking station, a stripping station, an embossing station, a printing station, a creasing station, a bending station, a shaving station, a trimming station, and/or any other station used in the tool and die industry. In a preferred embodiment, the station is a die cutting station. 
     According to various embodiments, a workpiece, such as a piece of paperboard stock, can be manipulated by a work station. The workpiece can comprise one or more sheets of paper, paperboard material, web, film, net, fibrous material, or the like, that can be manipulated by the work station. As the workpiece is manipulated by the work station, the paper pushing device of the present teachings can be used to prevent problems such as catching, snagging, and lodging of the stock, blank, skeleton, and/or waste. Although referred to as a paper pushing device, it is to be understood that the device, system, and method of the present teachings can apply to the manipulation of other materials than paper. 
     According to various embodiments, the paper pushing device of the present teachings can comprise a resilient and/or elastic material such that when a pressure is applied to the paper pushing device, the device can be configured to be elastically deformed. When the pressure is removed, the device can elastically rebound to its original position. An example of materials that can be used to form the paper pushing device can include, but are not limited to, polymeric materials, polyethylene (PE), polyurethane (PU), polypropylene (PP), cyclic polyolefin materials, polyoxymethylene (POM), polytetrafluoroethylene (PTFE), other plastic materials, aluminum, stainless steel, titanium, combinations thereof, and/or any other suitable material that provides elasticity. The paper pushing device can comprise acetal resin, for example, DELRIN® acetal resin, available E.I. du Pont de Nemours and Company, Wilmington, Del. 
     In some embodiments, the paper pushing device can be configured such that when a force is applied to the contact surface, the paddle can compress due to the force. The paddle can be configured, however, to elastically rebound in response to retraction of the applied force. The elasticity of the paper pushing device can allow for the paddle to return, rebound, and/or recoil to an original position, repeatedly. In some embodiments, the contact surface of the paddle can contact a workpiece, causing the paddle to become compressed. The paddle can be configured to elastically rebound so as to apply sufficient pressure to a resulting manipulated workpiece to push the workpiece out of the station and/or clear it from die rules, creasing rules, perforating rules, or other manipulating devices in the station. The paper pushing device can be configured to push a workpiece and thereby separate the workpiece, from surrounding scrap. For example, the paper pushing device can be configured to push a work product out of a manipulating station and away from scrap material, for example, out of a die cutting station. 
     According to various embodiments, the shaft can comprise a first diameter. The base can have a width that is greater than the first diameter of the shaft. The retaining board can comprise an operational surface. The operational surface can comprise an opening for receiving the paper pushing device. The opening in the retaining board can be wide enough to allow the shaft to be inserted therein but to be snugly fit therein. The opening of the retaining board can be narrow enough so as to prevent the arm from being inserted into the opening. In some embodiments, the retaining board can comprise a plurality of openings, each for receiving a respective paper pushing device. Each opening can extend all the way through the retaining board, but in some embodiments, the opening does not extend all the way through the board and instead has a bottom surface. In some embodiments, the end of the shaft can be configured to contact the bottom surface of the opening. 
     According to various embodiments, the operational surface of the retaining board can comprise one or more openings for receiving any number of tool and/or die components. Each opening can comprise, for example, a slot, a gap; a groove, a recess, a hole, a through-hole, or another type of opening. The openings can be configured so as to receive, hold, anchor, and/or lock in place any number of tool and die components. For example, the retaining board can comprise openings to receive, hold, anchor, and/or lock in place dies, compressible cushioning devices, paper pushing devices, paper lifting devices and/or any other tool and die components. The retaining board can comprise any known board material, for example, metal, wood, plastic, composite, a combination thereof, or the like. 
     According to various embodiments, the paper pushing device of the present teachings can be configured to push paper away from a die rule that is disposed in a retaining board or other substrate. In some embodiments, the paper pushing device of the present teachings can be configured to push a workpiece out of a vacuum hold. The paper pushing device can be configured to press against a workpiece such that the workpiece is prevented from getting stuck to components mounted in or on a retaining board. In some embodiments, the paper pushing device can be used in a stripping station or a blanking station. The paper pushing device can be configured to be disposed in an interference area of a male stripper device to prevent scrap material from lifting up after stripping has occurred. 
     With reference to the drawings, a paper pushing device  10 , according to various embodiments of the present teachings, can comprise a shaft  20 . Shaft  20  can have a first diameter. The diameter of shaft  20  can be from about 0.01 inch to about 2.00 inches, for example, from 0.10 inch to 1.00 inch, or from about 0.20 inch to 0.50 inch, or about 0.224 inch. As will be appreciated, the diameter of shaft  20  of the paper pusher  10  is not limited to a specific range of values, and cross-sectional shapes other than circular shapes can be used. Shaft  20  can comprise a distal end  22  and a support end  24  opposite the distal end. In some embodiments, shaft  20  can be of the same diameter from distal end  22  to support end  24 . Shaft  20  can comprise a central axis that runs parallel to the length of shaft  20 . 
     According to various embodiments and as illustrated in  FIGS. 1-5 , paper pushing device  10  can comprise an arm  26  that intersects with support end  24  of shaft  20 . Arm  26  can extend at an angle relative to support end  24  of shaft  20 . Arm  26  can extend at an angle that is in a range of from 88° to 98°, from 89° to 96°, from 90° to 95°, or at about 90°. Arm  26  can have any suitable dimensions. For example, arm  26  can have a length of about 0.5 to about 3.0 inches, from about 1.0 to about 2.0 inches, or of about 1.5 inches, about 1.6 inches, about 1.7 inches, or about 1.8 inches. In some embodiments, the length of arm  26  is about 1.697 inches. According to various embodiments, the exact angle at which arm  26  extends from shaft  20 , is not necessarily limited to a specific range of values. 
     In some embodiments, arm  26  can comprise a base  28 , a shoulder  30 , and a paddle  32 . A first end of base  28  can connect to support end  24  of shaft  20 , and a second end of base  28  can connect to shoulder  30 . The thickness, length, and width of base  28  are not limited to the specific dimensions described herein. 
     As will be appreciated, arm  26  does not need to comprise each of these parts. In some embodiments, one or more of the above mentioned parts for arm  26  can be removed, replaced or combined. 
     According to various embodiments, paddle  32  can comprise a lower first section  34  and an elevated second section  36 . The elevated second section  36  can extend upwardly from lower first section  34 . Elevated second section  36  can be angled with respect to lower first section  34  at an angle of from about 110° to about 160°, for example, from about 115° to 150°, from 120° to 130°, or at about 120°. Elevated second section  36  of paddle  32  can have a divergent intermediate section  36   a  and an end section  36   b  that extends from divergent intermediate section  36   a . As shown more clearly in  FIG. 2 , and section  36   b  can comprise a rounded distal edge. The rounded edge of end section  36   b  can have any suitable radius of curvature. According to some embodiments the radius of curvature of the rounded edge can be from about 0.01 inch to about 0.06 inch, or from about 0.02 inch to about 0.05 inch, or about 0.032 inch. 
     As shown in  FIG. 2 , the thickness of base  28  can remain the same. The thickness of base  28  can be from about 0.05 inch to about 1.5 inches, from 0.1 inch to 1.0 inch, or from about 0.2 inch to about 0.8 inch. The thickness of base  28  can be about, for example, 0.110 inch. Base  28 , however, is not limited to this design. Base  28  can instead be designed according to various embodiments to have a first thickness that is narrower at the first end, and a second thickness that is wider at the second end, or vice versa. The thickness of paddle  32  can be less than the thickness of base  28 . The thickness of paddle  32  can be from about 0.05 inch to about 0.10 inch, from about 0.06 inch to about 0.9 inch, or from about 0.07 inch to about 0.08 inch. Paddle  32  can instead be designed according to various embodiments to have a first thickness that is narrower at a first end, and a second thickness that is thicker at a second end. 
     According to various embodiments and as illustrated in  FIG. 2 , arm  26  can extend away from shaft  20  at an angle with respect to support end  24  of shaft  20 . As shown in  FIG. 2 , arm  26  can extend from support end  24  of shaft  20  at an angle of approximately 90°. As will be appreciated, the angle at which arm  26  extends from support end  24  is not limited to a specific angle and can be within any of a number of ranges of angles, for example, the angle can be within the range of from 90° to 100°. As shown in  FIG. 2 , shoulder  30  can intersect with base  28  of arm  26  at an angle of about 30° to about 80°, or from 40° to 60°, or from 45° to 50°. Paddle  32  can extend from shoulder  30  at an angle of about 30° to about 80°, from about 40° to about 70°, from about 50° to about 60°, or of about 55°. As will be appreciated, the angle with which paddle  32  extends from shoulder  30  and shoulder  30  extends from base  28  is not limited to a specific angle and can be within any appropriate range of angles. 
     According to various embodiments and as illustrated in  FIG. 2 , paddle  32  can comprise a contact surface  35 . Contact surface  35  can be configured to contact a workpiece. In some embodiments, contact surface  35  can be generally planar. Contact surface  35  is not limited to a planar design, and can be of any shape desired. 
       FIG. 3  shows a bottom view of the paper pushing device  10 , in which an undersurface  40  of paddle  32  can be seen. As shown in  FIG. 3 , lower first section  34  of paddle  32  can be generally rectangular shaped. It will be appreciated, however, that the shape of paddle  32  is not limited to this design. In some embodiments, paddle  32  can be rectangular, trapezoidal, oval, elliptical, triangular, or of any other shape. Elevated second section  36  of paddle  32  can have a width that is greater than the width of lower first section  34  of paddle  32 . Lower first section  34  of paddle  32  can comprise a width of from about 0.2 inch to about 0.6 inch, for example, from 0.25 inch to 0.5 inch, about 0.3 inch, about 0.4 inch, or about 0.5 inch. The width of lower first section  34  of paddle  32  can remain the same. Upper second section  36  can have a width that is narrower at least at a portion of intermediate divergent section  36   a , and wider at end section  36   b . Upper second section  36  of paddle  32  can comprise a width of from about 0.4 inch to about 0.8 inch, for example, from 0.4 inch to 0.6 inch, about 0.4 inch, about 0.5 inch, or about 0.6 inch. As is shown, the width of base  28  can be the same as lower first section  34 . 
     According to various embodiments, and as shown in  FIGS. 4 and 5 , paper pushing device  10  can comprise one or more splines  40   a  and  40   b , protruding from an outer surface of shaft  20 . Splines  40   a  and  40   b  can extend substantially along the length of shaft  20  between support end  24  and distal end  22  of shaft  20 . Splines  40   a  and  40   b  can be arranged at opposite sides of shaft  20 . Splines  40   a  and  40   b  can further secure shaft  20  in a retaining board. Splines  40   a  and  40   b  can protrude about 0.01 to about 0.05 inch from the outer surface of shaft  20 . In some embodiments, splines  40   a  and  40   b  protrude about 0.016 inch above the outer surface of shaft  20 . 
     Although not shown in the FIGS., paper pushing device  10  can comprise one or more annular protrusions extending away from shaft  20 , for example, as described in U.S. patent application Ser. No. 12/426,699, which incorporated herein in its entirety by reference. Each annular protrusion can comprise a diameter that is greater than the diameter of shaft  20 . Each annular protrusion can extend perpendicularly relative to the longitudinal axis of shaft  20 . In some embodiments, shaft  20  does not comprise any annular protrusions. 
     According to various embodiments, the paper pushing device of the present teachings can be implemented in a system. The system can comprise a substrate, for example, a retaining board, and one or more paper pushing devices mounted in the substrate. The substrate can comprise an operational surface that can be configured to receive, hold, anchor, secure, and/or lock in place any number of components for use in die cutting, rotary cutting, burst cutting, stripping, blanking, cutting, embossing, printing, or other workpiece manipulation activities. An example of a retaining board that can be used is as described in U.S. patent application Ser. No. 12/426,699, which is incorporated herein in its entirety by reference. 
     According to various embodiments, the paper pushing device of the present teachings can be used in a stock manipulation method. The method can comprise processing a workpiece, for example, in at least one manipulation station. The at least one station can comprise at least one of a stripping station, a blanking station, an embossing station, a printing station, a combination thereof, or any other tool and die station. The method can comprise manipulating a stock to form a manipulated workpiece. 
     According to various embodiments, the method can comprise expelling a workpiece from the at least one station with a paper pushing device. The paper pushing device can comprise any of the features listed previously, for example, a shaft configured to be received in an opening of a retaining board, an arm extending away from the shaft and comprising a base, a paddle, and a shoulder disposed between the base and the paddle. The expelling can comprise bending the paddle with an applied force and subsequently pushing the workpiece with the paddle. 
     Other embodiments will be apparent to those skilled in the art from consideration of the present specification and practice of various embodiments disclosed herein. It is intended that the present specification and examples be considered as exemplary only.