Abstract:
An apparatus to feed elongated metallic workpieces to a manufacturing process including a storage hopper configured to hold a plurality of workpieces that are randomly oriented and a movement device having a workpiece support that is automatically engageable with a workpiece.

Description:
[0001]    This application is directed to a method and apparatus for transporting metal objects. This application claims priority in Provisional Patent Application Ser. No. 60/985,434 that was filed on Nov. 5, 2007 which is incorporated by reference herein. 
     
    
       [0002]    The present invention relates to transporting metal objects and more particularly to a method and apparatus for transporting steel billets from a randomly oriented condition in a staging area to a conveying system for further processing of the billets. 
       INCORPORATION BY REFERENCE 
       [0003]    Metal billets and other elongated metal objects can be used for a wide range of manufacturing processes. This requires that these billets be moved or transported through the manufacturing processes from when they are formed to when they are processed to produce other products. As can be appreciated, movement of these billets, or elongated objects, from a storage area to a processing phase of a facility can be accomplished by many means. As with other manufacturing processes, robots can be used for the transportation of objects. U.S. Pat. No. 3,587,872 discloses a mechanical arm and control means therefor that can be used to pick and place objects wherein this patent is incorporated by reference herein as background material showing same. U.S. Pat. No. 4,283,165 discloses a motorized manipulator having a robotic arm configuration which is incorporated by reference herein as background material showing the same. U.S. Pat. No. 4,698,775 discloses a self-contained mobile reprogrammable automation device which is also incorporated by reference herein as background material relating to devices used to move objects. U.S. Pat. No. 4,501,522 discloses a manipulator that can be used to transport objects wherein this patent is also incorporated by reference herein as background material. U.S. Patent Publication No. 2006/0157476 discloses an apparatus and method for induction heating a piece of electrically conductive material which is incorporated by reference herein for showing the same. U.S. Pat. No. 4,806,066 which discloses a robotic arm that includes opposed grippers which is incorporated by reference herein as background material showing the same. U.S. Pat. No. 6,626,630 discloses a Cartesian robot which is a linear style actuator which is also incorporated by reference herein as background material showing the same. 
       BACKGROUND OF THE INVENTION 
       [0004]    Billets and other elongated objects have been used in manufacturing for many years wherein these objects must be moved or transported from one process to the next, stored, removed from storage and even manipulated or orientated for certain operations between the creation of the billet and the final processing of the billet. In the past, many methods have been used to transport or move these objects which include manual movement, vibratory feeders, conveyors, bins and pushers. These devices can be utilized to move or transport the billets from a first position to a second position. 
         [0005]    As can be appreciated, the location and orientation of the billet must be known before the billet can be moved from the first position to a second or known position. Further, interengagement with a desired number of billets at the first position, when the billet is in a randomly oriented condition, requires either manual manipulation by an operator or the use of sensors or other vision-type features on the movement device to properly orient the device. In this respect, and with respect to traditional jaws or grippers utilized in pick and place style manipulators, the device must know the orientation of the billet to properly align the jaws of the movement device with respect to the billet such that the jaws can grasp the billet. Once the billet is grasped, it can be manipulated as is needed for the particular operation. Not only does the movement device need to sense the position of the billet, it also must be able to articulate the jaws to properly orient the jaws relative to the billet to grasp the billet. As can be appreciated, this articulation can require multi-axis equipment so that the jaws can be oriented relative to the billet. The need for both vision and multi-axis articulation can greatly increase the costs of the device and can also greatly reduce the reliability and longevity of the device. This is especially true in the harsh environment typically associated with billet processing 
       STATEMENT OF INVENTION 
       [0006]    In accordance with the present invention, a system to feed an elongated metallic workpiece to a manufacturing process is provided wherein this system includes an automatically orienting gripping mechanism to interengage with a randomly oriented elongated object, such as a metallic billet, and a movement device that transports the object to a subsequent processing point such as to a conveying system that can be used to feed subsequent operations. 
         [0007]    In this respect, in one embodiment, provided is a system to feed elongated metallic workpieces to a manufacturing process wherein the elongated workpieces have a workpiece body extending along a workpiece axis between a first workpiece end and a second workpiece end. The system includes a storage hopper configured to hold a plurality of the workpieces that are randomly oriented and a movement device. The movement device includes a frame and a workpiece support joined to the frame wherein the workpiece support is moveable between a load position proximate the hopper and an unload position away from the load position. This workpiece support further includes an engaging surface and a flexible extension joining the engaging surface to the frame thereby allowing the engaging surface to move relative to the frame and a means for selectively producing an attractive force between the engaging surface and a workpiece to direct the engaging surface to a desired number of the workpieces regardless of the position of the workpieces when the engaging surface is in the load position. The attractive force means can selectively secure the desired number of workpieces relative to the engaging surface in the load position and release it in the unload position. 
         [0008]    According to another aspect of the present invention, the system can further include a self-alignment apparatus to generally align the workpiece axis of the desired workpiece relative to the conveyor axis near the unload position. 
         [0009]    According to a further aspect of the present invention, the system can include a conveyor at the unload position wherein the conveyor has a first conveyor end and a second conveyor end with a drive line moving along a driveline axis from the first conveyor end to the second conveyor end such that the second conveyor end directs the workpieces into a process and the unload position is over the conveyor. 
         [0010]    According to another aspect of the present invention, the system can be configured to secure a single workpiece and in another embodiment two workpieces. 
         [0011]    According to a further aspect of the present invention, the movement device can be a robotic arm. 
         [0012]    According to yet a further aspect of the present invention, the movement device can be a linear actuator. 
         [0013]    According to a further aspect of the present invention, the manufacturing process is an induction heating process. 
         [0014]    According to another aspect of the present invention, the self-alignment feature is a pair of angled baffles positioned on either side of the drive line at the unload position. 
         [0015]    According to yet a further aspect of the present invention, the pair of angled baffles is adjustable transverse to the conveyor axis to accommodate different size workpieces. 
         [0016]    According to a further aspect of the present invention, the attractive force includes magnetic. 
         [0017]    According to another aspect of the present invention, the attractive force includes a vacuum. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The foregoing, and more, will in part be obvious and in part be pointed out more fully hereinafter in conjunction with a written description of preferred embodiments of the present invention illustrated in the accompanying drawings in which: 
           [0019]      FIG. 1A  is a elevated layout view of a manufacturing operation including an embodiment of a system for transporting elongated objects according to the present invention wherein the system is shown in a load position; 
           [0020]      FIG. 1B  is the elevated layout view of  FIG. 1A  wherein the system is shown in an unload position; 
           [0021]      FIG. 2  is a perspective view of the movement device as is shown in  FIG. 1 ; 
           [0022]      FIG. 3  is an enlarged perspective view of a workpiece support including multiple engaging components; 
           [0023]      FIG. 3A  is a sectional view taken along lines  3 A- 3 A in  FIG. 3 ; 
           [0024]      FIG. 4  is an enlarged perspective view of a workpiece support including a single engaging component; 
           [0025]      FIG. 4A  is a sectional view taken along lines  4 A- 4 A in  FIG. 4 ; 
           [0026]      FIG. 5  is a perspective view of another embodiment of the present which includes an orientation device at least partially spaced from the unload position shown in  FIG. 1B ; 
           [0027]      FIG. 6  is an enlarged perspective view of a workpiece support according to another aspect of the present invention which includes powered rotation; 
           [0028]      FIG. 7  is a partially sectioned elevational view showing a workpiece support in relation to a conveying system above the unload position; 
           [0029]      FIG. 8  is a partially sectioned elevational view showing the workpiece support in relation to a conveying system in the unload position; 
           [0030]      FIG. 9  is a sectional view taken generally along lines  9 - 9 ; and 
           [0031]      FIG. 10  is partially sectioned elevational view showing the workpiece support in relation to a conveying system in the unload position showing a workpiece having a different cross sectional configuration. 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0032]    Referring now in greater detail to the drawings wherein the showings are for the purpose of illustrating preferred embodiments of the invention only and not for the purpose of limiting the invention,  FIGS. 1A and 1B  show a manufacturing operation or system  10  that includes a storage hopper  20  and a manufacturing process  30  with a conveying system  40  capable of feeding a workpiece W into manufacturing process  30 . As can be appreciated, the manufacturing process can be a wide range of manufacturing processes including, but not limited to, a heating process to heat workpiece W. This heating process can be an induction heater and workpiece W can be a metal billet. However, the invention of this application should not be limited to the induction heating of metal billets. 
         [0033]    Manufacturing operation  10  further includes a movement device  50  configured to feed workpiece W to conveying system  40 . In this respect, movement device  50  is configured to move a workpiece between a load position  60  ( FIG. 1A ) and an unload position  62  ( FIG. 1B ). The movement device can be any one of a number of motion devices including, but not limited to, pick and place devices, robotic arms, linear drives, and/or rotational drives configured to move a workpiece support  70  to position  60  such that the workpiece support can engage one or more workpieces W in hopper  20 , to remove the workpiece from hopper  20  and to move the workpiece towards position  62  wherein the workpiece can be deposited on conveying system  40 . As a result, the workpieces in hopper  20  can be controllably moved from the hopper to the conveyor such that workpiece W can be conveyed into a manufacturing operation. 
         [0034]    As is discussed above, manufacturing operation  30  can be any one of a number of operations or multiple operations including an induction heating operation used to heat a metal billet for further processing in the manufacturing facility. Since the invention of this application has been found to work particularly well in connection with metal billets and induction heating, it is being described herein in connection with this application. However, as can be appreciated, the invention of this application is broader in its application. 
         [0035]    Hopper  20  can be any storage device used in manufacturing or other applications including a reusable containers and/or a disposable container  72 . Further, storage hopper  20  can be a fixed hopper positioned on a surface such as the floor or a moving hopper wherein the storage hopper is, for example, rolled into position on a separate conveyor system, not shown. As can be appreciated, either style storage hopper can include the use of a disposable cardboard container mounted to a packing skid  74  such that a forklift can position a full hopper and remove an empty hopper as is needed. Whether a movable or a stationary hopper is utilized, the hopper can include a tilting feature  76  to at least partially tilt the hopper for aiding in the positioning of the workpieces in the hopper when, for example, only a few workpieces are remaining in the hopper. 
         [0036]    As can be appreciated, the size and configuration of the storage hopper can vary greatly depending on the size of the workpiece and the production rate of the facility. As will be discussed in greater detail below, these differing sizes and configurations can impact the configuration of the workpiece support. 
         [0037]    With reference to  FIGS. 1-6 , movement device  50  is configured to move the workpiece support between load position  60  and unload position  62  such that the workpieces can be controllably transported from a storage condition to a processing condition regardless of the orientation of the workpiece in the hopper. Holder  70  accomplishes this by being configured to controllably secure and release one or more workpieces and; further, to engage a desired number of the workpieces for each cycle of the system from the load to the unload position automatically. Yet even further, this automatic engagement of the desired number of workpieces is achieved without manual manipulation, vision, sensors or powered actuation relative to the movement device. This allows movement device  50  to be a simple and reliable device and further simplifies the corresponding control or operating system such that costs are reduced and, repeatability and reliability are increased. 
         [0038]    In one embodiment, movement device  50  is a multi-axis robot having a support pedestal  100  with rotating base  102  secured to pedestal  100 . Device  50  further includes a first arm  104  joined to base  102  by a first pivot connector  106 . Device  50  can further include a second arm  110  pivotally joined to arm  104  at a second pivot joint  112 . By including second arm  110 , the range and mobility of device  50  can be increased. Further, second arm  110  helps allow workpiece holder  70  to enter into hopper  20 . 
         [0039]    Workpiece holder  70  is joined to arm  110  and can also be joined by a pivoting or articulating joint such as a workpiece joint  120 . By including joint  120 , the range of motion of holder  70  is further increased. 
         [0040]    The movement device is controlled by an operating system  130  that controls the desired movement of the movement device. In addition, operating system  130  can also be configured to operate one or more other devices in system  10 . Operating system  130  can be any operating system known in the art including, but not limited to, a computer operating system. 
         [0041]    In one embodiment, holder  70  includes a workpiece arm  150  joined at a first end  152  to joint  120  such that arm  150  extends to a distal end  154 . Arm  150  can be a rigid member as is shown in at least one embodiment of this application. However, is will be discussed in greater detail below, arm  150  also can be a flexible member. 
         [0042]    With special reference to  FIGS. 3 and 3A , shown is a workpiece support configuration  70 B wherein the workpiece support includes a quick change hanger arrangement  160  that can be used to quickly reconfigure system  10  according to the parameters of the manufacturing operation. In this respect, hanger  160  can be used in combination with quick change lock blocks  168  to change the number of engagement members, the spacing between the members, the length of the members etc. which can be modified based on the hopper configuration and/or the workpiece configuration which will also be discussed in greater detail below. Hanger  160  and lock blocks  168  can use any quick change technology known in the art without detracting from the invention of this application. 
         [0043]    Workpiece holder  70 B is configured to engage two workpieces. Hanger  160  is joined to arm  150  by a flexible member  162  which can be used to increase the range of motion of the workpiece holder. Flexible members  164  and  166  extend between blocks  168  and the respective engagement members  174  and  176  wherein the length of members  164  and  166  can also be used to control the range of motion of holder  70 B. Engagement members  174  and  176  further include attraction and support devices  180  and  182  wherein members are spaced such that holder  70 B is configured to engage a single workpiece. As is discussed throughout this application, engagement devices  180  and  182  can include a wide range of technologies used to locate and support (attract) randomly oriented workpieces. This includes permanent magnets, electro-magnets and other magnetic technologies, a vacuum, or any other method of attracting another object. 
         [0044]    Engagement devices  180 ,  182  in this embodiment are electro-magnets positioned at or near engagement surfaces  184  and  186 , respectively, wherein these magnets are joined to operating system  130  by leads  170  and  172  which control when the electro-magnets are on and/or off. Since members  174  and  176  magnetically engage metal workpiece W, the members selectively secure themselves to the workpieces automatically based on attractive forces alone along with the movement device moving the holder within range of the workpieces. 
         [0045]    In order to ensure that each engagement member  174  and  176  picks only a single workpiece, spacing D 1  between flexible members  164  and  166  and length D 2  of flexible members  164  and  166  can be configured such that each engagement device is not capable of engaging the same elongated object. As can be appreciated, spacing D 1  and length D 2  is based on the configuration and size of the workpiece. 
         [0046]    In yet another embodiment of the invention of this application, components  180  and  182  can be permanent magnets wherein these magnets are joined to a linear actuator such that they move relative to surfaces  184  and  186 , respectively. As these permanent magnets move away from engagement surfaces, the magnets loose their effect and the members are then in the “off” condition. Conversely, when the permanent magnets are in a position proximate to the corresponding engagement surface, the member is in the “on” condition. As with the other embodiments in this application, the permanent magnets can also be controlled by operating system  130 . 
         [0047]    In any embodiment in this application, some or all of the remaining components can be made from non-magnetizable materials to help prevent unwanted magnetization of these other components thereby preventing unwanted attractive forces. 
         [0048]    By utilizing magnets in combination with flexible members  162 ,  164  and  166 , engagement devices  174  and  176  can automatically locate a respective billet without the need for sensors and/or vision components in movement device  50 . As can be appreciated, the size of storage hopper  20  will, at least in part, dictate the amount of motion that is necessary to allow engagement devices  174  and  176  to find a workpiece within the hopper. Further, tilting device  76  can be used in connection with hopper  20  to minimize the range of motion necessary to direct the engagement members to the workpieces within the hopper. For example, larger hoppers could necessitate the need for longer flexible devices. As a result of this system, the engagement devices can be simply lowered into the hopper and then automatically engage a workpiece from a randomly oriented pile of workpieces. 
         [0049]    In yet another embodiment of the invention of this application, movement device  50  can include a simple sensor in communication with operating system  130  to let the operating system know that a workpiece has been engaged and secured. 
         [0050]    With reference to  FIGS. 4 and 4A , workpiece support  70 C is shown. This embodiment includes hanger  160  and lock blocks  168  to allow for quick changeovers. Again, workpiece W is shown which is an elongated member having a circular cross-sectional configuration. In this embodiment, engagement member  200  includes a shaped engaging surface  202  configured to matingly engage with the outer cylindrical surface of workpiece W. As with the embodiments discussed above, workpiece support  70 C includes flexible member  162  and can further include a flexible member  163  configured to allow engagement member  200  to adequately move within the storage hopper to engage a workpiece. This particular configuration is designed to engage a single workpiece. However, more than one engagement member  200  could be mounted to hanger  160  without detracting from the invention of this application. Further, engagement member  200  can includes a centrally located magnet  208  proximate to surface  202  to magnetically engage the workpiece when in load position  60 . As with the other embodiment in this application, magnet  208  can be an electro-magnet connected to operating system  130  by way of electrical connection  210  or an actuated permanent magnet, vacuum or any other attractive force technology. 
         [0051]    With reference to  FIGS. 7-10 , even a randomly oriented workpiece retrieved from hopper  20  can be oriented properly on conveyor system  40 . In one embodiment, conveyor system  40  can include angled baffles  250  and  252  that are spaced from one another on either side of conveyor belt  254 . This conveyor system can be any known conveyor system and, therefore, it will not be discussed in greater detail in this application. Angled baffles  250  and  252  can be joined to conveyor  40  by way of adjustable brackets  260  wherein brackets  260  can include elongated slot  262  which can be used in connection with a fastener  264  to modify spacing S between the baffles based on the size of workpiece W. As workpiece W is lowered toward belt  254 , baffles  250  and  252 , in combination with flexible members  162 ,  164  and  166 , align workpiece W such that it is generally parallel to edges  270  and  272  of belt  254  when it reaches the belt. In yet another embodiment, baffles  250  and  252  can be powered baffles connected to a linear actuation device (not shown) to allow quick adjustments to be made to spacing S. This powered system can also be connected to operating system  130 . 
         [0052]    With reference to  FIG. 6 , workpiece holder  70 D is shown. This embodiment does not include a hanger assembly. Conversely holder  70 D includes a single engagement member  200  connected to a flexible member  222  which is joined directly to workpiece joint  120 . This embodiments can function similar to those discussed above; however, it further a rotational device  230  that can further help orient the workpiece holder and/or the workpiece during any point of the process. Further, rotational device  230  can be either a powered rotational device and/or a freely rotating device which can be used to help orientation. Yet even further, rotational device  230  can include a locked and an unlocked condition. Again, these features will be discussed in greater detail below. 
         [0053]    With respect to loading the workpiece, when the workpiece support is in load position  60 , rotational device  230  can be in an unlocked condition to allow the full and free movement of the engagement device relative to the movement device to help the alignment between the engagement member and the workpiece. Then, the rotational device can be mechanically moved to a set position to properly orient the workpiece relative to the conveyor belt before it reaches the conveyor. This arrangement is best suited for the workpiece support that includes a shaped engagement surface as is shown in  FIG. 6 . 
         [0054]    With reference to  FIG. 5 , the alignment or baffle structure can be spaced from the unload position. In this respect, shown is an alignment shoot  300  that can be positioned between load position  60  and unload position  62  and can include multiple alignment surfaces such as surfaces  302 ,  304 ,  306  and  308 . As workpiece W is moved through alignment device  300  by the motion produced by movement device  50 , one or more of the surfaces of workpiece W engage one or more surfaces  302 ,  304 ,  306  and  308  which then begin to orient the workpiece relative to these known surfaces. This can be done in combination with selectively rotatable rotation device  230  or the other flexible members discussed above to align the workpiece. 
         [0055]    In one embodiment, as workpiece W enters engagement device  300 , rotational device  230  can be unlocked to allow the free rotation of the workpiece relative to the alignment device. Then, once the workpiece is aligned, rotational device  230  can be locked. In addition, the flexibility of the flexible members could also be locked in yet another embodiment. As a result of this alignment feature, the orientation of the workpiece relative to the movement device would be known after the workpiece passes through the orientation device such that it can be positioned on the conveyor system without further orientation. 
         [0056]    In yet even a further embodiment, rotational device  230  can provide, at least in part, the free rotational movement necessary to help align the workpiece with the conveying system as the workpiece engages baffles  250  and  252 . 
         [0057]    As is shown in  FIG. 9 , the invention of this application can be used with other workpiece configurations without significant modification. In this embodiment, angle baffles  250  and  252  are adjusted based on the size and shape of workpiece W 2  wherein the square cross-sectional configuration of workpiece W 2  can be properly oriented to the conveyor. 
         [0058]    In yet another embodiment of the invention of this application, the strength of the magnet used in connection with any one of the work holders can be configured to only support a single billet which can also be used to ensure that only the desired number of workpieces is engaged by the workpiece holder in the load position. 
         [0059]    While considerable emphasis has been placed on the preferred embodiments of the invention illustrated and described herein, it will be appreciated that other embodiments and/or equivalents thereof can be made and that many changes can be made in the preferred embodiments without departing from the principles of the invention. Accordingly, it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.