Abstract:
An apparatus that provides a continuous flow of parts to a manufacturing robot during a manufacturing process has a plurality of adjustable parts caddies on rotating carousel where the parts used in manufacturing process are placed in each adjustable caddy on an operator side of the apparatus and then taken out of the caddy on a production side as the carousel turns. A lift mechanism on the production side works in conjunction with the adjustable caddies and a manufacturing robot to position parts in each caddy in a predefined position for pick up by the manufacturing robot.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority under 35 U.S.C. §119 of U.S. Provisional Application Ser. No. 61/763,004 filed on Feb. 11, 2013 the content of which is relied upon and incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The disclosure relates generally to a system and apparatus for facilitating an automated manufacturing process, more particularly it relates to a system and apparatus for providing a steady and uninterrupted stream of prepositioned articles in a manufacture process for robot pickup. 
     BACKGROUND 
     Human operators have been tending, loading and unloading manufacturing machines for many years. While human operators allow for flexibility in the manufacturing process, they also introduce errors due to the repetitive nature of automated mass assembly lines, they add to cost, and require frequent downtime. Modern day manufacturing practices dictate continual process improvement including: increased part quality, increased throughput, increased reliability, decreased part cost, reduced scrap, and continuous operation sometimes 24/7. One method for meeting these goals is the use robotics. Industrial robots are good at repetitive motions and are very good at material handling such as pick and place applications. Robots minimize the variables an operator introduces when handling parts such as, improper part placement into the manufacturing machine, dropped or damaged parts or even the inconsistency in loading or unloading a waiting manufacturing machine in a timely manner. Many times the use of robotics enables a human operator to control operation of multiple manufacturing machines as opposed to being tied to tending just one machine. 
     One critical aspect for the successful implementation of robotic manufacturing and material handling applications is that parts must be presented to the manufacturing robot in a consistent, reliable and repeatable method. The second aspect is that the human operator understands supports and is able to provide a continuous uninterrupted supply of parts to the manufacturing robot during the production process. Accordingly, there is a need in the industry for a method and apparatus for providing an intuitive consistent parts supply for robot assisted manufacturing. 
     SUMMARY 
     Thus, robotic tending machines that provide an uninterrupted flow of parts to a robotic manufacturing machine during the manufacturing process are important parts of the robotic manufacturing process. By providing a steady flow of parts to the robotic manufacturing system they ensure an uninterrupted operation of the system that maximizes its value. 
     In one variation the present invention provides a system that can provide an uninterrupted flow of parts to a robotic manufacturing machine. It includes a carousel with eight adjustable part caddies placed on arms on the periphery of the carousel. Each parts caddie holds a stack of pans needed in a robotic manufacturing process, such as gears or similar parts. The carousel rotates successively into a dispensing position each caddy full of parts needed in the specific manufacturing process. At the parts dispensing position, a mechanical lift arm raises the stack of parts which sit on a movable lift plate to a position where a robotic manufacturing arm takes each part in the raised stack and uses it in the manufacturing process that the robotic manufacturing system has been programmed to do. As the robotic arm takes a part from the stack the mechanical lift arm in response to a signal sent to the systems control computer by an appropriately placed sensor then incrementally moves the stack of parts up so that the next part in the stack is in the predetermined position to be grasped by the robotic arm. When the caddy is emptied of all parts, the system lowers the empty lift plate and then positions itself below the carousel. The carousel then rotates the next full parts caddy into the dispensing position and the process starts over. On the side of the carousel opposite the dispensing position, clam shell type doors can be rotated open and shut by operator at the tending station who refills the empty caddies with parts to assure the uninterrupted flow of manufacturing process. The rotating doors are designed to limit the amount of space needed for the system. 
     In another variation of the invention the parts supply caddy includes: a) a base plate with at least three posts movably mounted at a first end of the posts to a top surface of the base plate; b) a lever plate with at least three slot shaped apertures which allow the lever plate to be placed over the movably mounted posts and allow the posts to protrude up through the lever plate which lever plate rests on top of the base plate and wherein when the lever plate is moved with respect to the base plate it changes the position of the movably mounted posts to thereby provide a variable holding space between the posts to hold a stack of items of varying size depending on the space between the posts as determined by movement of the lever plate; c) the at least three movably mounted posts are movably mounted by offset extended base portions from a pivot point such that they are movable in an arch about the pivot point, which pivot points are located on a circumference of a circle about a center of the base plate; d) the lever plate is detachably and rotatably attached at the center of the base plate and the slot shaped apertures in the lever plate through which the posts project are formed in the shape of an arch such that when the lever plate is rotated about its center on the base plates the posts move in unison either in towards or out away from the center of the lever plate to thereby describe a variable space that can hold a stack of items of varying size depending the extent the lever plate is rotated; e) a lift plate with three slotted apertures through which the three pivotally mounted posts can project, the lift plate being position able over the lever plate and the slots of the lift plate configured to accommodate movement of the posts by the lever plate such that a stack of items can be placed on the lift plate within the space between the posts and wherein the lift plate extends beyond an edge of the base plate and the lever plate to thereby allow an elevating mechanism to lift the lift plate off of the lever plate and thereby lift a stack of items on the lift plate for prepositioning items at the top of the stack of items for access by a manufacturing robot; and f) a scale positioned at a periphery of the lift plate such that a flange projecting from the lever plate, when the lift plate is positioned on the lever plate aligns with the scale and when calibrated can accurately define the space provided between the posts when the lever plate is moved to adjust a position of the posts. 
     In another aspect of the invention it provides a parts supply apparatus for providing a continuous supply of parts for a manufacturing process that includes: a) a carousel rotatable about a center; b) a plurality of adjustable parts caddies positioned on the carousel, the parts caddies being adjustable to hold stacks of parts of varying size and each caddy having a lift plate to allow the moving up of a stack of parts placed on the caddies; c) a power source to rotate the carousel about its center; d) a production side stop position wherein each parts caddy can be successively positioned by rotation of the carousel to position each of the parts caddies with parts for access by a manufacturing robot; e) an operator side stop position wherein each of the parts caddies can be successively positioned by rotation of the carousel to position each of the parts caddies for placing a stack of parts in the caddy; and f) a lift arm at the production side stop position for engaging the lift plate of each of the parts caddies as they are successively positioned at the production side stop position for lifting the lift plate with a stack of items to a predetermined placement position at which a manufacturing robot can grasp an item at the top of a stack of items on the lift plate. 
     In yet another variation of the invention it provides a method for providing a continuous flow of work pieces for a manufacturing robot during a manufacturing operation which method includes the steps of: a) providing a carousel rotatable about a center, b) providing a plurality of adjustable parts caddies; c) positioning said plurality of adjustable parts caddies on said carousel, said plurality of parts caddies being adjustable to hold stacks of work pieces of varying size and each caddy having a lift plate to allow the lifting up of a stack of work pieces placed on said plurality of caddies; d) providing a power source to rotate said carousel about its center; e) rotating in incremental steps said carousel so that each of said plurality of caddies can be successively positioned at a production side stop position where worked pieces positioned in each said caddies can be accessed by a manufacturing robot; f) successively positioning each of said caddies after it has been emptied of work pieces at an operations position wherein each of said caddies can be successively filled with a new set of work pieces; and g) providing a lift arm at said production side stop position for engaging said lift plate on each of said plurality of parts caddies positioned at said production side stop position for progressively lifting said lilt plate with a stack of work pieces to a predetermined placement position at which a manufacturing robot can grasp a work piece at the top of a stack of work pieces on said lilt plate. 
     Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from the description or recognized by practicing the embodiments as described in the written description and claims hereof, as well as the appended drawings. 
     It is to be understood that both the foregoing general description and the following detailed description are merely exemplary, and are intended to provide an overview or framework to understand the nature and character of the claims. 
     The accompanying drawings are included to provide a further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiment(s), and together with the description serve to explain principles and operation of the various embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the base plate with moveable posts: 
         FIG. 2  is a perspective view of lever plate placed over the base plate with the post projecting through the lever plates; 
         FIG. 3  is a perspective view of the base plate and lever plate with the lift plate sitting on top of the lever plate; 
         FIG. 4  is perspective view of a carousal with adjustable parts caddies around its periphery; 
         FIG. 5  is a perspective view of the system from the operator side: 
         FIG. 6  is a perspective view of the system from the production side; 
         FIG. 7  is a top plane view of the system including the elevation mechanism for lifting the lift plate on each caddy; 
         FIG. 8  is a side view of the lift arm and lift fork; and 
         FIG. 9  is a perspective view of the system from the production side adjacent to the robotic arm. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  provides a perspective view of the primary structure of the caddy. Base plate  101  has three adjustable posts  103   a ,  103   b  and  103   c . Each post at its base is attached to one end of a moveable arm  105   a ,  105   b  and  105   c . The opposite end of each movable arm  105   a ,  105   b  and  105   c  are rotate-ably attached to base plate  101  at pivot points  107   a ,  107   b  and  107   c  respectively. The base plate  101  also has at its center retention post  109 . 
     Referring to  FIG. 2 , placed over posts  103   a ,  103   b  and  103   c  is an adjustable lever plate  211  above base plate  101 . Adjusting lever plate  211  has adjusting knob  215  which allows for the rotational motion of the plate around a center retention post  109  to which the center of adjusting lever plate is rotate-ably attached. Each of the posts  103   a ,  103   b  and  103   c  project up through curved adjusting slots  217   a ,  217   b  and  217   c  on adjusting lever plate  211 . Adjusting slots  217   a ,  217   b  and  217   c  have a curvature so that when knob  215  is either moved clockwise or counterclockwise around center retention post  109 , the three posts  103   a ,  103   b  and  103   c  move in unison either inward or outward. This movement allows for precisely positioning each one of the posts at the same distance from the center point, namely center retention post  109 . 
       FIG. 3  provides a perspective view of a fully assembled adjustable parts caddy  301 . Lift plate  309  is positioned over the three posts  103   a ,  103   b  and  103   c  of base plate  101  with adjusting lever plate  211  positioned between them. Each post  103   a ,  103   b  and  103   c  projects up through lift plate slide slots  323   a ,  323   b  and  323   c  respectively in lift plate  309 . Lift plate  309  is not physically attached to the base plate  101 . Lift plate  309  rests on and the adjusting lever plate  211  and is not attached to it. Additionally, lift plate  309  has post position or parts size measuring scale  311  along its outside periphery. When adjusting lever plate  211  is moved by moving adjusting knob in either clockwise or counterclockwise direction, posts  103   a ,  103   b  and  103   c  move back and forth in unison in slots  323   a ,  323   b  and  323   c . This is caused by their moving along the curved slots of adjusting lever plate  211 . An indexing slot  221  in knob  215  indicates on scale  311  the outside radius of parts that can be placed in the caddy. Lift plate  309  also has retention notch  313 . Given the configuration of the slots  323   a, b  &amp;  c  in plate  309  the orientation of scale  311  remains in the same and correct orientation even as adjustable lever plate  211  is rotated to change the position of posts  103   a, b  &amp;  c.    
     Referring to  FIG. 4 , in the embodiment of the invention shown therein adjustable parts caddy carousel  421  has eight adjustable caddies  301  located around its periphery on arms  425 . Each arm has a notch holding pin  427  that holds the top plate of each adjustable caddy in place by fitting into retention notch  313  of each of the caddies. Carousel  421  is connected at its center by four bolts  429  to a motive and control apparatus  431  located thereunder. Naturally depending on the circumference of carousel  421  and the size of parts caddies  301  the number of parts caddies that can be positioned on a carousel made according to the present invention can vary. Thus, given these variables the carousel and parts caddies can vary in size and the number of parts caddies on the carousel can vary from less than eight to twelve or more. As can be seen in  FIG. 4  parts caddy  409  is filled with a stack of gears. 
       FIG. 5  provides a perspective view of the overall parts supply system from the operator tending side  501 . Outer rotary door  503   a  and inner rotary door  503   b  are in a partially open position. Both doors attach at pivot point  509  and have bearings or some other means at their base to allow them to freely slide in a clockwise or counter clockwise direction to provide access to the caddies or enclose the tending side as needed. Thus doors  503   a  and  503   b  can be opened or closed by simply sliding the interior door  503   b  under the outer door  503   a  or vice versa, sliding outer door  503   a  over interior door  503   b . This provides ready access for an operator without the need for excessive floor space that would be necessitated by a standard hinged door. Thus, the operator can access and easily fill the cadies  301  on carousel  421  as each empty caddy rotates around to the operator side after robot arm  505  has emptied each full caddy at the dispensing or production stop position. Robotic arm  505  picks up each part from the pre-positioned caddies. Additionally, the system control station  507  is positioned adjacent to the system and provides computer and electronic control of the operation of the system. It contains a standard programmable computer which can be programmed to operate the system in the desired manner. Fork lift fork sheaths  515  allow for the insertion of the forks of a fork lift into the base of the system so the system can be easily moved around and positioned in the manufacturing facility. 
       FIG. 6  is a perspective view of the manufacturing production side  601  of the current system. Dispensing position  603  is visible adjacent to lift arm  607 . Additionally, lift fork  605  which curves around the posts of the caddy located at the dispensing position is at its fully top extended position without a lift plate on it for illustrative purposes. Laser sensor  609  is positioned to determine if a part is located at the appropriate position for robotic arm  505  to take the next part. The information provided by laser sensor  609  tells the control system  507  to advance lift fork  605  by means of lift arm  607  up to the next position to properly position parts that would be on a lift plate. Once the last part in the stack of parts placed on the caddy has been removed lift fork  605  will have reached its highest position and the sensor signals that there are no longer any parts left with this caddy. Accordingly, it signals lift arm  607  to drop lift fork  605  down to a position below carousel  421  to thereby allow carousel  421  to advance the next full caddy to dispensing or production stop position  603 . The process is then repeated where the lift plate  309  of the caddy  301  full of parts that is now positioned at dispensing position  603  is emptied of pans in the same fashion. As can be seen in  FIG. 6  lift fork  605  is in the shape of fork or horseshoe in the embodiment depicted. 
       FIG. 7  provides a top view of the system where the tender/operator side  501  appears and the production/manufacturing side  601  is positioned opposite it. Doors  503   a  and  503   b  are in the closed position. Lift fork  605 , which attaches by connector  703  to lift arm  607  can be seen. Additionally, sprocket  707  and drive chain  705  of lift arm  607  can be seen. 
     Referring to  FIG. 8 , a side view of lift arm  607  is presented with lift fork  605 , chain  705  and the lower sprocket  807  of the lift arm. Lift arm drive motor  801  is operatively connected to sprocket  807  which in turn drives chain  705  to control movement of lift fork  605 . Motor  801  is controlled by computerized control system  507 . 
       FIG. 9  is a perspective view of the system from the production side adjacent to robotic arm  505  and shows the system in operation. Lift fork  605  holds lift plate  309  of parts caddy  301   a , which has four work pieces  905  left on it. After manufacturing robot arm  505  removes all of the work pieces  905  from lift plate  309   a  lift arm  607  will lower lift fork  605  to a point below parts caddy  301   a  and the bottom of carousel  421 . Once lift fork  605  is at its fully retracted position  611  carousel  421  will then advanced in a clockwise direction to the left in  FIG. 9  to bring the next full parts caddy  301   e  to the production stop position  603  where lift arm  607  will lift the lift plate  309  of caddy  301   e  with work pieces  905  on it in to the predetermined position where robot arm  505  will pick each work piece in sequence and use the work piece in the particular manufacturing process it is engaged in. Empty parts caddy  301   b  is visible in  FIG. 9  it having been emptied of work pieces. Also, parts caddies  301   c  and  301   d  are visible on the operator side of the system where they have been refilled with more work pieces. Laser sensor  609  positioned on top of lift arm  607  and as noted is operatively connected to the computer control system and is used to determine if the work pieces are in the predetermined position for pick up by robot arm  505  and when the caddy has been completely emptied so the next full caddy can be moved into the production stop position to continue the manufacturing process. 
     Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that any particular order be inferred. 
     It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the invention. Since modifications combinations, sub-combinations and variations of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and their equivalents.