Method for optimization of an order of component mounting, apparatus using the same, and mounter

Abstract

The following processing is performed when a line gang pickup head can simultaneously pick up a maximum of n (here, 4) components. First, groupings of components of the same type, out of all of the components to be optimized, are set as component tapes and the component tapes are arranged descending order of the number of components to produce a component histogram ( 406 a ). Next, a partial histogram ( 400 ), which is part of the component histogram ( 406 a ), is taken from the component histogram ( 406 a ), and is arranged at two-dimensional coordinates where a horizontal axis (the Z-axis) represents an arrangement of component cassettes and a vertical axis represents a number of pickup operations by the line gang pickup head. After this, the component tapes are lined up, by arranging the partial histograms ( 401 a and 401 b ), so as to produce a diagram ( 406 b ) whose width (number of components) in the horizontal axis is n (=4).

1 . An optimizing method that optimizes, using a computer, a component mounting order for a mounter equipped with a mounting head that picks up components from an arrangement of component cassettes that hold the components and mounts the components on a substrate, the optimizing method comprising: 
 a task group generating step for generating task groups that are arrangements of tasks, a task being a set of components that are mounted in one iteration of a repeated series of operations in which the mounting head picks up, transports, and mounts components; and    a task interchanging step for changing an order of tasks within each task group so as to minimize a time required to mount all components each task group, and setting a mounting order of components corresponding to a resulting order of tasks as an optimal component mounting order.    
   
   
       2 . The optimizing method according to  claim 1 , wherein the task interchanging step rearranges an order of tasks in each task group so as to minimize paths taken by the mounting head, each path being from a position where the mounting head completes a mounting of all components in one task to a position where the mounting head picks up components for a next task to be mounted.  
   
   
       3 . The optimizing method according to  claim 2 , 
 wherein a position of the mounting head immediately after completing a mounting of all components in one task is set as a final mounting point and a position at which the mounting head picks up components belonging to a next task to be mounted is set as a pickup point,    and the task interchanging step includes:    a shortest looped partial path specifying step    for selecting an arbitrary first task in a task group, specifying the final mounting point for the first task,    for selecting, out of all remaining tasks in the task group, a second task whose pickup point is closest to the final mounting point of the first task,    for repeating a process specifying the final mounting point of a selected task and then selecting a next task until the first task is selected again, and    for setting all tasks that have been selected as a shortest looped partial path;    a repeating step for having the shortest looped partial path specifying step repeated until every task in the task group has been selected; and    an arranging step for arranging the shortest looped partial paths that are produced as a result of the repeating step having the shortest looped partial path specifying step repeated.    
   
   
       4 . The optimizing method according to  claim 3 , 
 wherein in the task interchanging step, a first task for each shortest looped partial path and an order of the shortest looped partial paths are determined so as to minimize distances moved by the mounting head from a completion of a mounting of all components in a shortest looped partial path to a start of a next shortest looped partial path, and tasks are reordered in accordance with the determined order of shortest looped partial paths.    
   
   
       5 . An optimizing apparatus that optimizes, using a computer, a component mounting order for a mounter equipped with a mounting head that picks up components from an arrangement of component cassettes that hold the components and mounts the components on a substrate, the optimizing apparatus comprising: 
 task group generating means for generating task groups that are arrangements of tasks, a task being a set of components that are mounted in one iteration of a repeated series of operations in which the mounting head picks up, transports, and mounts components; and    task interchanging means for changing an order of tasks within each task group so as to minimize a time required to mount all components composing each task group, and setting a mounting order of components corresponding to a resulting order of tasks as an optimal component mounting order.    
   
   
       6 . A mounter that is equipped with (1) an arrangement of component cassettes which hold component tapes, a component tape being a group of components of a same type, and (2) a mounting head that picks up components from the arrangement of component cassettes and mounts the components on a substrate, 
 wherein after the mounting head has mounted every component in a task, a task being a set of components that are mounted in one iteration of a repeated series of operations in which the mounting head picks up, transports, and mounts components, the mounting head then mounts a task, out of remaining tasks, whose components are picked up at a position which requires a least amount movement by the mounting head.    
   
   
       7 . A computer program which, when executed by a computer, has the computer optimize a component mounting order for a mounter equipped with a mounting head that picks up components from an arrangement of component cassettes that hold the components and mounts the components on a substrate, 
 the computer program causing the computer to function as:    task group generating means for generating task groups that are arrangements of tasks, a task being a set of components that are mounted in one iteration of a repeated series of operations in which the mounting head picks up, transports, and mounts components; and    task interchanging means for changing an order of tasks within each task group so as to minimize a time required to mount all components each task group, and setting a mounting order of components corresponding to a resulting order of tasks as an optimal component mounting order.    
   
   
       8 . A computer-readable storage medium on which a computer program according to  claim 7  is recorded.  
   
   
       9 . An optimizing method that optimizes, using a computer, a component mounting order for a mounter equipped with a mounting head that picks up a maximum of n components, n being no less than 2, from an arrangement of component cassettes that hold the components and mounts the components on a substrate, the optimizing method comprising: 
 a task group generating step for generating task groups that are arrangements of tasks, a task being a set of components that are mounted in one iteration of a repeated series of operations in which the mounting head picks up, transports, and mounts components; and    a component interchanging step for changing, within each task group, a mounting order of components so as to minimize a time required to mount all components composing the task group, without changing a combination of component types in each task.    
   
   
       10 . An optimizing method according to  claim 9 , 
 wherein the task interchanging step includes:    a selecting step for selecting two components of a same type at random;    a judging step for judging whether a total mounting time of a task group containing the two selected components decreases when a mounting order of the two selected components is interchanged; and    an interchanging step for interchanging the two selected components in the mounting order when the judging step judges that the total mounting time decreases.    
   
   
       11 . An optimizing method according to  claim 9 , 
 wherein the task interchanging step includes:    a judging step for judging whether a total mounting time of a task group decreases when two sets of components that are consecutively mounted on a substrate are interchanged between two tasks in the task group that are composed of a same combination of component types; and    an interchanging step for interchanging the two sets of components when the judging step judges that the total mounting time decreases.    
   
   
       12 . An optimizing method according to  claim 9 , 
 wherein the task interchanging step includes:    a detecting step for detecting, for a case where for each task, straight lines are drawn between mounting points on the substrate of adjacent components that are picked up and belong to a task, whether there is an intersection between straight lines that belong to two different tasks that are composed of combinations of the same component types; and    an interchanging step for interchanging, when the detecting step has detected an intersection, components of the same component type between the two tasks to eliminate the detected intersection.    
   
   
       13 . An optimizing apparatus that optimizes, using a computer, a component mounting order for a mounter equipped with a mounting head that picks up a maximum of n components, n being no less than 2, from an arrangement of component cassettes that hold the components and mounts the components on a substrate, the optimizing apparatus comprising: 
 task group generating means for generating task groups that are arrangements of tasks, a task being a set of components that are mounted in one iteration of a repeated series of operations in which the mounting head picks up, transports, and mounts components; and    task interchanging means for changing, within each task group, a mounting order of components so as to minimize a time required to mount all components composing the task group, without changing a combination of component types in each task.    
   
   
       14 . A mounter that is equipped with (1) an arrangement of component cassettes which hold component tapes, a component tape being a group of components of a same type, and (2) a mounting head that picks up components from the arrangement of component cassettes and mounts the components on a substrate, 
 wherein a task is a set of components that are mounted in one iteration of a repeated series of operations in which the mounting head picks up, transports, and mounts components, and    the mounter mounts components belonging to two tasks that    (i) are composed of a same combination of component types and    (ii) have a risk of there being an intersection between straight lines which are drawn between mounting points on the substrate for adjacent components that are picked up    using mounting paths chosen so that there is no intersection between the straight lines.    
   
   
       15 . A computer program which, when executed by a computer, has the computer optimize a component mounting order for a mounter equipped with a mounting head that picks up a maximum of n components, n being no less than 2, from an arrangement of component cassettes that hold the components and mounts the components on a substrate, 
 the computer program causing the computer to function as:    task group generating means for generating task groups that are arrangements of tasks, a task being a set of components that are mounted in one iteration of a repeated series of operations in which the mounting head picks up, transports, and mounts components; and    task interchanging means for changing, within each task group, a mounting order of components so as to minimize a time required to mount all components composing the task group, without changing a combination of component types in each task.    
   
   
       16 . A computer-readable storage medium on which a computer program according to  claim 15  is recorded.  
   
   
       17 . An optimizing method of optimizing, using a computer, a component mounting order in which a production line composed of at least two mounters mounts a plurality of components on a substrate, each mounter being equipped with a mounting head operable to pick up at least two components from an arrangement of component cassettes that store components, operable to transport the components by moving using an X-Y robot, and operable to mount the components on a substrate, said optimizing method comprising: 
 assigning the components to each mounter in units of task groups, a task group being an arrangement of tasks wherein a task is a set of components mounted in one iteration of a repeated series of operations in which the mounting head picks up, transports, and mounts the components.