Abstract:
The present disclosure generally relates to a method for dispensing material from a roll. The method monitors the weight of a first material roll using a load cell attached to a frame holding the first material roll. The method dispenses material from the first material roll. The method determines, based on at least the weight of the first material roll, when to remove a second material roll from a refrigerator or freezer to reduce the amount of time between the thawing of the second roll and replacing the first roll with the second roll. Also disclosed is an apparatus for dispensing the material from the roll.

Description:
INTRODUCTION 
       [0001]    The present disclosure generally relates to a method and apparatus for dispensing fiber prepreg material from rolls compatible with high-volume manufacturing conditions, where the prepreg rolls require a refrigeration-thawing cycle. 
       BACKGROUND 
       [0002]    Fiber composite materials, also known as prepregs, are composite materials having a reinforcement fiber that is pre-impregnated with a thermoplastic or thermoset resin matrix. The resin holds the fibers together and enables formation of unidirectional fibers or fabric. The amount of resin within the matrix is generally the amount desired in the final composite material so that no additional resin need be applied during manufacturing, hence the name “prepreg.” The resin matrix in a prepreg is usually partially cured for ease of handling. Sheets of prepreg are provided with silicone-coated paper on each side and sold in a roll format. The prepreg material is applied to an article then heated, for example in an autoclave, to fully cure and polymerize the resin in the desired shape composite article. The prepreg rolls are stored in a freezer, generally at 0° F. for up to six-months, to prevent premature polymerization or curing during storage. 
         [0003]    Manufacturing composite materials requires thawing the prepreg after removal from the freezer for a set period of time. Thawing of such a material can take several hours, sometimes upwards of 16 hours. The amount of time a prepreg material spends at room temperature is critical to its shelf-life. When a prepreg roll is removed from the freezer, the amount of time it is out of the freezer must be carefully noted. This is generally referred to as the roll&#39;s “out-time.” If the entire roll is not consumed during one out-time, the remainder be returned to the freezer to preserve the material&#39;s shelf life. 
         [0004]    As manufacturing volume increases, the present inventors have found several problems with conventional prepreg roll systems resulting in either downtime of the manufacturing line or unacceptable waste due to out of time material. When working through a roll of prepreg, it is critical to know exactly how much material is left on the roll to determine whether removing the next roll from the freezer will be necessary to complete a job. Operators will begin to thaw the next roll if they estimate they will need additional material to complete a project. In practice, this requires keeping track of exactly how much material has been removed from a roll and the rate at which it is being removed. 
         [0005]    If the operator underestimates the amount of material left on the roll, and begins unnecessarily thawing a new roll, that material could exceeding its out-time and is therefore wasted. If the operator overestimates the amount of material left on the roll, the entire process might shut down while awaiting the next roll begins to thaw. This can also result in problems with uncured material present on a partially built workpiece. If the uncured prepreg goes out-time, then the partially built uncured part could be sacrificed. 
         [0006]    In order to avoid out-time prepreg, operators base their estimate the amount of remaining material by keeping track of the length of plies cut from a roll of material. These estimates often contain rounding error, gauge error, and typographical errors in maintaining the amount of material cut. The result is that preparation, including thawing, of the new roll begins too early or too late and the corresponding wasted material or process downtime as discussed above. Although these methods have worked for lower volume manufacturing operations, as throughput has increased the need systems that better monitor and control the process are needed. 
       SUMMARY 
       [0007]    The present invention generally relates to a novel method for dispensing material from a roll. The method monitors the weight of a first material roll using a load cell attached to a frame holding the first material roll. The method dispenses material from the first material roll. The method determines, based on at least the weight of the first material roll, when to remove a second material roll from a refrigerator or freezer to reduce the amount of time between the thawing of the second material roll and replacing the first material roll with the second material roll. 
         [0008]    The present invention also relates to a method that determines an amount of a first material roll by measuring a weight of the first material roll. The method determines whether the weight is below a threshold. The threshold is associated with an amount of time at which all of the first material roll is unrolled. The method transmits an alert to prepare a second material roll before the first material roll is empty. 
         [0009]    The present invention also relates to an apparatus including a frame. The apparatus includes a first material roll disposed on the frame. The apparatus includes a load cell configured to monitor the weight of a first material roll. The apparatus includes a system configured to determine, based on at least the weight of the first material roll, when to remove a second material roll from a refrigerator or freezer to reduce the amount of time between the thawing of the second material roll and replacing the first material roll with the second material roll. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  illustrates an exemplary embodiment of a just-in-time (JIT) rolled material system. 
           [0011]      FIG. 2  illustrates an exemplary embodiment of an exploded view of the JIT rolled material system. 
           [0012]      FIG. 3  illustrates an exemplary embodiment of a JIT rolled material system when an alert is generated. 
           [0013]      FIG. 4  illustrates an exemplary embodiment of a wireless transmission from the JIT rolled material system. 
           [0014]      FIG. 5  illustrates an exemplary embodiment of the JIT rolled material system and a new roll staging area. 
           [0015]      FIG. 6  illustrates an exemplary embodiment of the JIT rolled material system process of efficiently switching material rolls. 
           [0016]      FIG. 7  illustrates an exemplary embodiment of a JIT rolled material system. 
           [0017]      FIG. 8  presents an example system diagram of various hardware components and other features, for use in accordance with an example implementation of a communication apparatus. 
           [0018]      FIG. 9  conceptually illustrates a process for the JIT rolled material system. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. 
         [0020]    The present invention relates to a system and method for dispensing material from a roll. In an embodiment, the first material roll is of fiber composite materials, also known as prepregs, which are composite materials having a reinforcement fiber that is pre-impregnated with a thermoplastic or thermoset resin matrix. The resin holds the fibers together and enables formation of unidirectional fibers or fabric. Prepregs that may be used in the present invention include Plainweave, 5Harness, Lighting Strike, Fiberglass, and Core Splice. However, one of ordinary skill in the art will appreciate that rolled material according to the invention is not limited to those listed above. 
         [0021]      FIG. 1  illustrates an exemplary embodiment of a just-in-time (JIT) rolled material system  100 . As shown, the JIT rolled material system includes a roll of lifetime limited material  105 , a spindle  110 , a load cell  115 , a frame  120 , communication apparatus  130 , unrolled material  130  and cutting table  135 . As shown, the frame  120  of the JIT rolled material system  100  supports the spindle  110 . The roll  105  is supported by the spindle  110 . As the material  130  is unrolled from the roll material  105  onto the cutting table  135 . The cutting table  135  may be an automated cutting table configured to cut a predefined amount of material off of the roll  105 . The roll  105  of material may be a roll of a prepreg material such as the prepregs discussed above. 
         [0022]    The load cell  115  is arranged with the spindle  110 . The communication apparatus  125  is arranged with the frame  120  and communicatively coupled to the load cell  115 . 
         [0023]    The load cell  115  is configured to measure the weight of the spindle  110  and the material roll  105  and convert the measurement to an electronic signal. The electronic signal may then be received at the communication apparatus  125 . The communication apparatus  125  may comprise a computer system having a processor configured to process the information received from the load cell  115 . For instance, the communication apparatus  125  may receive an electronic signal comprising information about the measured weight of the spindle  110  and the roll  105 . The processor may compare the weight information to a threshold weight. If the measured weight is the threshold weight or below, the communication apparatus may transmit an alert. As will be described in greater detail below, such an alert may include transmitting a wireless notification, displaying a notification, and/or generating an audible alarm. The notification may be used to notify an operator that it is time to prepare a new roll of material because the material roll  105  is likely to run out of material at approximately the same time as it would take to prepare a new roll of prepreg material. 
         [0024]    For instance, a roll of “lightning strike” material, manufactured by Cytec Industries, Inc., is known to require 16 hours of thaw time. Accordingly, the communication apparatus  125  may be configured to generate the alert when the communication apparatus  125  determines that the roll  105  may run out of material in about 16 hours. In such instances, the communication apparatus  125  may receive input from an operator of the JIT rolled material system  100  of a known weight at which the roll will be emptied in 16 hours. Such input may be received by an input device such as a keyboard at the communication apparatus  125  or via a wireless signal received from another device. The known weight corresponds to an amount of material. Similarly, the communication apparatus  125  may receive an input of a length to set as the threshold. The communication apparatus  125  may maintain a storage of the weight per linear foot of different types of prepreg materials and the communication apparatus  125  may convert the input length to a weight based on the weight per linear foot of the material type. The communication apparatus  125  may then generate an alert when the weight measured by the load cell  115  reaches the converted weight. 
         [0025]    The JIT material system  100  improves production efficiency with lifetime limited materials like prepregs by providing precise weight measurements that correlate with the amount of material left on the roll. The ability to precisely identify the amount of material remaining on a roll provides the operator(s) of the JIT material system  100  the ability to ensure that a replacement roll of material is ready for use at approximately the same time as the roll  105  runs out of material. Thus, the lifetime limited material does not suffer from the complications that come from beginning preparation of the new roll too soon or too late. 
         [0026]      FIG. 2  illustrates an exemplary embodiment of an exploded view of the JIT rolled material system  200 . The JIT rolled material system  200  includes a lifetime limited material roll  205 , a spindle  210 , a load cell  215 , a frame  220 , and a communication apparatus  225 . The components  205 - 225  of the JIT rolled material system correspond to the components  105 - 125  of the JIT rolled material system  100  of  FIG. 1  and the description of the components will not be repeated for simplicity. 
         [0027]      FIG. 3  illustrates an exemplary embodiment of a JIT rolled material system  300  when an alert is generated. The JIT rolled material system  300  includes a lifetime limited material roll  305 , a spindle  310 , a load cell  315 , a frame  320 , a communication apparatus  325 , and an alert  340 . The components  305 - 325  of the JIT rolled material system correspond to the components  105 - 125  of the JIT rolled material system  100  of  FIG. 1  and the description of the components will not be repeated for simplicity. 
         [0028]    As shown, the amount of lifetime limited material left on the roll  305  is below the predetermined threshold amount discussed above with respect to  FIG. 1 . As a result, the communication apparatus  325  has generated an alert  340 . As discussed above, the alert  340  may be audio and/or visual notification from the communication apparatus  325 . Alternatively or conjunctively, the alert  340  may be a wireless transmission such as an email that is transmitted to an operator&#39;s email account. One of ordinary skill in the art will appreciate that the type of alert that is generated is not limited to those discussed above. Any suitable alert that notifies an operator that the amount of material on the roll is below the threshold would be sufficient without departing from the scope of the invention. 
         [0029]      FIG. 4  illustrates an exemplary embodiment of a wireless transmission from the JIT rolled material system  400 . The JIT rolled material system  400  includes a lifetime limited material roll  405 , a spindle  410 , a load cell  415 , a frame  420 , a communication apparatus  425 , electronic transmission  445 , and a computer  455 . The components  405 - 425  of the JIT rolled material system correspond to the components  105 - 125  of the JIT rolled material system  100  of  FIG. 1  and the description of the components will not be repeated for simplicity. 
         [0030]    As shown, similar to  FIG. 3 , the amount of lifetime limited material left on the roll  405  has fallen below a threshold amount. As a result an alert in the form of an electronic transmission  445  has been transmitted. Such transmissions may be transmitted over a wired or wireless network. The electronic transmission  445  may be transmitted to a wireless network, which then forwards the transmission to an email server. The email server may then provide the email message to the appropriate email account or group associated with the operator(s) of the JIT rolled material system  400 . Accordingly, an email alert may be available to the computer  455  for display. 
         [0031]    Additionally, the communication apparatus  425  may be configured to generate alerts at multiple threshold weights. For instance, the communication apparatus  425  may generate an alert at a threshold warning the operator that he has approximately 2 more hours until the preparation of a new roll should begin. With multiple thresholds, different email alerts may be generated indicating the type of threshold that may have been reached. 
         [0032]      FIG. 5  illustrates an exemplary embodiment of the JIT rolled material system  500  and new roll staging area  560 . The JIT rolled material system  500  includes a first material roll  505 , a spindle  510 , a load cell  515 , a frame  520 , a communication apparatus  525 , and alert  540 . The new roll staging area  560  includes a second material roll  565 . The components  505 - 525  of the JIT rolled material system correspond to the components  105 - 125  of the JIT rolled material system  100  of  FIG. 1  and the description of the components will not be repeated for simplicity. 
         [0033]    As shown, an alert  540  has been generated from the communication apparatus  525  because the weight of the material on the first roll  505  reached a threshold weight. The alert  540  indicates to the operator(s) of the JIT rolled material system that it is time to prepare the second roll  565  to replace the first roll  505  so as to maximize manufacturing time and cost efficiency. As a result, the second roll  565  has been removed from a freezer to begin the thawing process. The JIT rolled material system is designed such that the problems of thawing the roll too early or too late are eliminated. 
         [0034]      FIG. 6  illustrates an exemplary embodiment of the JIT rolled material system process of efficiently switching material rolls. As shown,  FIG. 6  illustrates four stages  601 - 604  of the process  600  for switching a material roll. The JIT rolled material system  600  includes a first material roll  605 , a spindle  610 , a load cell  615 , a frame  620 , a communication apparatus  625 , electronic transmission  645 , and a computer  655 . The components  605 - 625  of the JIT rolled material system correspond to the components  105 - 125  of the JIT rolled material system  100  of  FIG. 1 . The components  645  and  655  of the JIT rolled material system correspond to the components  445  and  455  of the JIT rolled material system  400  of  FIG. 4 . The description of these components will not be repeated for simplicity.  FIG. 6  also includes a cooling system  670 , a second material roll  665  of lifetime limited material, and a timer  675 . 
         [0035]    As shown, in the first stage  601 , an electronic transmission  645  is generated to alert the operator of the JIT rolled material system that the weight of the material on the first material roll  605  has reached the threshold. The transmitted alert may be viewed at the computer  655 . Accordingly, in the second stage  602 , the second material roll  665  of lifetime limited material is removed from the cooling system. Such a cooling system may be a freezer or a refrigerator that maintains a temperature below the temperature at which the lifetime limited material begins to cure. For instance, the cooling system  670  may maintain a temperature of below 10° C. 
         [0036]    In the third stage  603 , the new roll  665  may be moved to a staging area where it can thaw for the requisite amount of time for the type and amount of material on the second material roll  665 . The timer  675  may indicate the amount of time until the new roll  665  is thawed. However, the timer  675  could be comprised in any suitable device such as an operator&#39;s computer system running a software program that tracks the thaw time or out-time of the second material roll  665 . 
         [0037]    In the fourth stage the new roll  665  has completed thawing, and the first material roll  605  has been removed from the spindle  610 . In the fourth stage, the second material roll  665  completed thawing at around the same time as the JIT rolled material system is prepared to accept the second material roll  665 . Such preparation may include removing any waste from the first material roll  605  and recalibrating the load cell  615  and/or communication apparatus  625  for the second material roll  665 . For instance, the communication system  665  may receive input of the type of material on the second material roll  665  and determine new alert thresholds based on the known weight per linear foot of the second material roll  665 . Once the second material roll  665  is placed about the spindle  610 , the operators of the JIT rolled material system  600  may begin manufacturing again. Thus, the process of  FIG. 6  minimizes manufacturing downtime. The process also minimizes cost because the material is thawed at an optimal time minimizing the likelihood the second material roll  665  out-times, rendering it unusable. 
         [0038]      FIG. 7  illustrates an exemplary embodiment of a JIT rolled material system  700 . The JIT rolled material system  700  includes a lifetime limited material roll  705 , a spindle  710 , a load cell  715 , a frame  720 , and a communication apparatus  725 . The components  705 - 725  of the JIT rolled material system correspond to the components  105 - 125  of the JIT rolled material system  100  of  FIG. 1  and the description of the components will not be repeated for simplicity. 
         [0039]    The JIT rolled material system  700  is similar to the JIT rolled material systems of  FIGS. 1-6 . However, as illustrated in  FIG. 7 , the load cell  715  is disposed below the frame  720 . As a result, the weight of the frame  720 , along with the weight of the spindle  710  would be taken into consideration when determining the amount of material on the roll  705 . For instance, the weight of the frame  720  and the spindle  710  may be known. Accordingly, the communication apparatus  725  may be configured to subtract the weight of the frame  720  and the spindle  710  measured by the load cell when determining whether the amount of material on the roll  705  reaches the threshold value. 
         [0040]      FIG. 8  presents an example system diagram of various hardware components and other features, for use in accordance with an example implementation of a communication apparatus such as the communication apparatus described with respect to  FIG. 1  and similarly in  FIGS. 2-7 . 
         [0041]    Aspects of the communication apparatus may be implemented using hardware, software, or a combination thereof, and may be implemented in one or more computer systems or other processing systems. In one implementation, aspects of the communication apparatus are directed toward one or more computer systems capable of carrying out the functionality described herein. An example of such a computer system  800  is shown in  FIG. 8 . 
         [0042]    Computer system  800  includes one or more processors, such as processor  804 . The processor  804  is connected to a communication infrastructure  806  (e.g., a communications bus, cross-over bar, or network). Various software implementations are described in terms of this example computer system. The computer system  800  may be communicatively coupled to a load cell such as the load cell  115  in order to receive feedback associated with the weight of the roll. The processor  804  may process the weight and compare the measured weight to a threshold stored in memory. After reading this description, it will become apparent to a person skilled in the relevant art(s) how to implement aspects of the communication apparatus using other computer systems and/or architectures. 
         [0043]    Computer system  800  can include a display interface  802  that forwards graphics, text, and other data from the communication infrastructure  806  (or from a frame buffer not shown) for display on a display unit  830 . Computer system  800  also includes a main memory  808 , preferably RAM, and may also include a secondary memory  810 . The secondary memory  810  may include, for example, a hard disk drive  812  and/or a removable storage drive  814 , representing a floppy disk drive, a magnetic tape drive, an optical disk drive, etc. The hard disk drive  812  or the removable storage drive  814  may maintain the weight per linear foot of the different types of material. The removable storage drive  814  reads from and/or writes to a removable storage unit  818  in a well-known manner. Removable storage unit  818 , represents a floppy disk, magnetic tape, optical disk, etc., which is read by and written to removable storage drive  814 . As will be appreciated, the removable storage unit  818  includes a computer usable storage medium having stored therein computer software and/or data. Alternatively, the computer system  800  may not maintain any type of long term storage. As such, the computer system may be in communication with another computer system configured to provide the material weight information to the communication apparatus over a network connection. 
         [0044]    In alternative implementations, secondary memory  810  may include other similar devices for allowing computer programs or other instructions to be loaded into computer system  800 . Such devices may include, for example, a removable storage unit  822  and an interface  820 . Examples of such may include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an EPROM, or programmable read only memory (PROM)) and associated socket, and other removable storage units  822  and interfaces  820 , which allow software and data to be transferred from the removable storage unit  822  to computer system  800 . 
         [0045]    Computer system  800  may also include a communications interface  824 . Communications interface  824  allows software and data to be transferred between computer system  800  and external devices. Examples of communications interface  824  may include a modem, a network interface (such as an Ethernet card), a communications port, a Personal Computer Memory Card International Association (PCMCIA) slot and card, etc. Software and data transferred via communications interface  824  are in the form of signals  828 , which may be electronic, electromagnetic, optical or other signals capable of being received by communications interface  824 . These signals  828  are provided to communications interface  824  via a communications path (e.g., channel)  826 . This path  826  carries signals  828  and may be implemented using wire or cable, fiber optics, a telephone line, a cellular link, a radio frequency (RF) link and/or other communications channels. In this document, the terms “computer program medium” and “computer usable medium” are used to refer generally to media such as a removable storage drive  814 , a hard disk installed in hard disk drive  812 , and signals  828 . These computer program products provide software to the computer system  800 . Aspects of the invention are directed to such computer program products. 
         [0046]    Computer programs (also referred to as computer control logic) are stored in main memory  808  and/or secondary memory  810 . Computer programs may also be received via communications interface  824 . Such computer programs, when executed, enable the computer system  800  to perform the features in accordance with aspects of the present invention, as discussed herein. In particular, the computer programs, when executed, enable the processor  810  to perform various features. Accordingly, such computer programs represent controllers of the computer system  800 . 
         [0047]    In an implementation where aspects of the invention are implemented using software, the software may be stored in a computer program product and loaded into computer system  800  using removable storage drive  814 , hard drive  812 , or communications interface  820 . The control logic (software), when executed by the processor  804 , causes the processor  804  to perform various functions as described herein. In another implementation, aspects of the invention are implemented primarily in hardware using, for example, hardware components, such as application specific integrated circuits (ASICs). Implementation of the hardware state machine so as to perform the functions described herein will be apparent to persons skilled in the relevant art(s). 
         [0048]    In yet another implementation, aspects of the invention are implemented using a combination of both hardware and software. 
         [0049]      FIG. 9  conceptually illustrates a process  900  for the JIT rolled material system. The process  900  may be performed by the computer system  800  and the load cell  115 . The process  800  may start when a roll of material is loaded onto the JIT rolled material system. 
         [0050]    As shown, the process  900  determines (at  905 ) an amount of a first material roll by measuring the weight of the first material roll. The process  900  determines (at  910 ) whether weight is below a threshold associated with an amount of time at which all of the first material roll is unrolled. The process  900  transmits (at  915 ) an alert to prepare a second material roll before the first material roll is empty. 
         [0051]    This written description uses examples to disclose the invention, including the preferred embodiments, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims. Aspects from the various embodiments described, as well as other known equivalents for each such aspect, can be mixed and matched by one of ordinary skill in the art to construct additional embodiments and techniques in accordance with principles of this application.