JP2009200427A - Method for optimizing mounting operation in mounting line - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To correct operation environment of mounting machines to improve mounting accuracy of components when there is difference in tact time among a plurality of mounting machines constituting a mounting line. <P>SOLUTION: In the method for optimizing mounting operations in the mounting line, tact simulation is performed by giving priority to simultaneous attraction of a plurality of components and high-speed transfer of a mounting head, the slowest mounting machine is specified from the tact time calculated for each mounting machine by the tact simulation, and for at least a mounting machine in the previous step of the slowest mounting machine, individual attraction of the plurality of components or low-speed transfer of the mounting head is selected according to the difference in the tact time with the slowest mounting machine. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for optimizing a mounting operation in a mounting line, and in particular, in a plurality of mounting machines constituting the mounting line, not only a production tact time which is a production efficiency but also a suction operation of components included in the mounting operation as much as possible The present invention relates to a method for optimizing a mounting operation in a mounting line suitable for optimization after changing mounting operation and improving mounting accuracy.

  A mounting substrate that is completed through a mounting operation in which a target electronic component is picked up by a mounting head and then mounted on the substrate is usually produced in a mounting line that connects a plurality of mounting machines.

  During the production, a target production tact time is set as a required time for producing one board in the entire mounting line, and each mounting machine constituting the mounting line is satisfied so that the target tact time is satisfied. The combination is determined, and the mounted components are allocated to the determined mounting machines (see, for example, Patent Document 1).

  For example, in Patent Document 2, the mounting order is optimized for each mounting machine, and a tact simulation is performed based on the results. In this case, the variation in tact time between mounting machines is within an allowable range. Optimized to be

  By the way, when optimizing the mounting operation in the conventional mounting line, the target production tact time is set, and parts are distributed (production data allocation) on the condition that this line is satisfied. Some deviation occurs in the number of components to be mounted between mounting machines, and in this case, a mounting machine that waits without a substrate flowing on the line is generated.

  For example, if the balance of the number of components to be mounted on two mounting machines is 6: 4, the mounting machine on which 6 components are normally mounted has a longer tact time, so the board does not flow, Since the mounting machine having the component No. 4 has a short tact time, a waiting time is wasted.

JP 2004-146541 A JP-A-6-21690

  However, in the past, since there is a difference in the tact time between the mounting machines due to the uneven number of parts to be mounted for each mounting machine in the mounting line, especially when there is a congestion in the board flow on the line. I did not consider it.

  The present invention was made to solve the above-described conventional problems, and when there is a difference in tact time between a plurality of mounting machines constituting a mounting line, by correcting the operating environment of the mounting machine, It is an object of the present invention to provide a method for optimizing a mounting operation in a mounting line that can improve the mounting accuracy of components.

  In the present invention, a production tact time for producing a mounting board by sequentially mounting components distributed to a plurality of mounting machines constituting a mounting line on a board using a mounting head by each mounting machine is determined in advance. Tact simulation is performed so that it falls within the set target tact time, and in the mounting operation optimization method in the mounting line that determines the optimal mounting operation for each mounting machine, the tact simulation is simultaneously picked up and mounted on multiple components. Prioritize high-speed movement of the head, identify the slowest mounting machine that is the bottleneck from the tact time required for each mounting machine by the tact simulation, and at least one other than the slowest mounting machine For the mounting machine, according to the difference in tact time with the latest mounting machine, individual suction of multiple parts and mounting head Fast select at least one of movement, by changing the mounting operation, by improving the mounting accuracy is obtained by solving the above problems.

  In the present invention, when changing the mounting operation, low speed movement of the mounting head may be preferentially selected for a large component.

  According to the present invention, for a mounting machine other than the mounting machine having the maximum tact time, the operation environment is modified such that the component suction operation is individually picked up or the mounting operation is delayed according to the difference in tact time. As a result, the component mounting accuracy on the board can be improved accordingly.

  FIG. 1 is an image diagram showing an outline of a mounting line applied to an embodiment according to the present invention.

  This mounting line has a configuration in which three mounting machines indicated by mounting machines A to C managed by one host computer are connected in a row, and the components distributed to each mounting machine A to C are arranged. These are mounted sequentially on a substrate flowing in the same direction, and a mounting substrate is produced.

  A basic flow of mounting operation optimization in the present embodiment is shown in the flowchart of FIG. First, in step 1, the production data (including components to be mounted on the board and mounting coordinates) is allocated to each mounting machine, and in step 2, the feeder placement and distribution of the mounting parts distributed as production data for each mounting machine. The mounting order is determined by optimization.

  In the next step 3, line simulation (tact simulation) is executed based on the determined feeder arrangement and mounting order, and line tact time (tact time for each mounting machine) is measured (calculated). Whether or not the line tact time variation is within the allowable range is compared. If not, the processes in steps 1 to 3 are repeated until the line tact time variation is within the allowable range (step 4). The optimization process performed according to this flowchart is basically the same as in the case of Patent Document 2.

  Referring to FIG. 2 in detail, in the optimization of a single mounting machine, in order to improve the tact time of the single mounting machine, that is, in order to be able to mount the components allocated to each mounting machine in the shortest time, In 2, the order of suction and mounting operation is determined giving priority to simultaneous suction as much as possible.

  On the other hand, when viewed as optimization of the entire mounting line, there is no help for a specific mounting machine having a short tact time. For this reason, when allocating production data to each mounting machine in step 1, it is best that the tact time required for mounting the target component is uniform for each mounting machine. It is not necessarily uniform depending on external factors such as equipment status (difference in equipment).

  In that case, based on the result of the line simulation executed in step 3, the process returns to step 1 to reallocate the production data to each mounting machine, and the feeder allocation and mounting order of each mounting machine in step 2 for the reallocation result. Optimization is performed (step 4).

  That is, first, the reallocation of production data to each mounting machine is performed based on the result of the line simulation in Step 3, and then optimization is performed on each mounting machine.

  Here, regarding the mounting order in the mounting machine, when the simultaneous suction is possible by the plurality of nozzles of the mounting head, the simultaneous suction is prioritized. However, since it is more accurate to perform the sequential suction for individually picking up the components, the mounting accuracy is good. For example, the suction is prioritized when the suction is possible.

  In addition, the axis speed, which is the moving speed of the mounting head, is also the highest speed. For example, in the case of large parts with large inertial force, priority is given to mounting accuracy by reducing the speed, rather than shortening the tact time. It is possible that there is a good case.

  For this purpose, by referring to the tact time of the latest slowest mounting machine among the tact times required at the time of optimization of each mounting machine, and evaluating whether there is a margin in the tact time of each other mounting machine For a mounting machine with a margin, it is judged whether the simultaneous suction is broken from the optimized result to individual suction, or because it is a part with a large inertia force, the shaft speed is changed and slowed down. Tact time is calculated in consideration of

  This is because in the calculation of the production of multiple boards by line simulation, evaluation including the board transfer time is performed, and if the tact time of each mounting machine varies within the allowable range, the slowest mounting machine The production tact becomes a bottleneck, and a substrate in the middle of production may be in a standby state in the transfer buffer of the mounting machine in the previous process.

  Therefore, this line simulation result is referred to when optimizing each mounting operation of the mounting machine. For the mounting machine in the previous process of the slowest mounting machine, it is not necessary to process it quickly because the back is slow. Alternatively, the substrate transfer waiting time can be shortened by changing the axis speed.

  Next, the operation of this embodiment will be described.

  According to the flowchart of FIG. 2 described above, production data is allocated to each mounting machine (step 1), and feeder arrangement and mounting order in the mounting machine are determined by optimization based on the allocated production data (step 2). Then, line simulation is executed according to the optimized mounting order (step 3). By repeating this operation so that the variation of the tact time between the mounting machines is within the allowable range (step 4), the line tact time (here, the total tact time of the entire line) changes as shown in FIG. Finally, it converges to a substantially constant tact time.

  Next, optimization executed according to the present embodiment on the production data allocated to each mounting machine will be described according to the flowchart shown in FIG.

  First, the feeder arrangement in the mounting machine and the order of loading are determined, but the feeder arrangement is determined in the same manner as in steps 1 to 3 (step 11), and the order of loading from the same suction pattern is determined internally for the determined feeder arrangement. The tact time is calculated for the determined mounting order (step 13). When the mounting order of all assigned production data is determined (step 14), the accumulated line tact time is compared with the optimum tact time which is the target value (step 15).

  Here, the accumulated line tact time corresponds to the tact time of the latest mounting machine, and the optimum tact time corresponds to the tact time of the target mounting machine. This time is calculated using simultaneous adsorption and maximum shaft speed.

  As a result of comparison, when the optimum tact time is earlier (step 16) and the difference between the optimum tact time and the line tact time is within the allowable range, the difference is calculated from the mounting order data created for each mounting machine. Based on the appropriate mounting order data (step 17), the location to be changed is selected based on the component size, the number of simultaneous suctions, and the mounting tact, and the pattern that breaks the simultaneous suction and the pattern that changes the shaft speed are created. At the same time, the tact time is calculated for each pattern (step 18), and a data table as shown in FIG. 5 is created in advance.

  This data table is for the case where the components picked up from the two picking positions indicated by F-56 and F-58 for the target mounting machine are sequentially mounted on the 16 mounting coordinates (X, Y). This is an example of the result of calculating the tact time, which is the required time for the optimal tact time (standard pattern) when performing simultaneous adsorption as much as possible, and the simultaneous adsorption collapse tact time (when performing simultaneous adsorption) Pattern) and an axis speed change tact time (axis speed change pattern) when the XY movement of the mounting head is all performed at a low speed.

  Subsequently, the tact time calculated for each pattern is compared with the individual tact of each of the latest mounting machine that is the bottleneck determined from the result of the line simulation and the mounting machine that is the target of the preceding process. To select an appropriate pattern. That is, if the result of fitting the calculated tact time is good (if the tact time is fitted, it is within the line tact time) (step 19), it is output as the optimization result of the mounting machine (step 20). ).

  Here, regarding the selection of the appropriate pattern, the No. shown in the chart of FIG. 1 and No. The second pattern will be described as a specific example.

  Pattern No. 1 is the same example as in FIG. 2 is an example of the result of calculating the tact time in the same manner for each pattern when mounted on 16 mounting coordinates from F-60 and F-62 that can be simultaneously sucked.

  Now, as shown in FIG. 6, the optimum tact, simultaneous tact tact, and shaft speed change tact are represented by A, B, and C, respectively. It looks like the table.

  On the other hand, in this example, if the line tact time is 34.83 seconds and the optimum tact time is 32.81 seconds, the difference is 2.02 seconds.

  The difference within 2.02 seconds is the pattern No. 1 and No. 2 is B-A, and the pattern No. is closer. No. 2, so that the mounting operation is Replacement is performed to change to the simultaneous adsorption break-up pattern of 2.

  According to the embodiment described in detail above, the tact time of the latest mounting machine determined by calculating the tact time by tact simulation is compared with the tact time of the mounting machine of the previous process, and according to the difference The accuracy of the pre-mounting machine can be improved within a range that does not affect the target line tact time.

  As the mounting machine to which the present invention is applied, the mounting machine in the previous process is optimal from the viewpoint of preventing the occurrence of traffic jams, but it can be applied to any mounting machine other than the latest mounting machine from the viewpoint of improving mounting accuracy. Needless to say.

Explanatory drawing which shows the outline | summary of the mounting line applied to one Embodiment which concerns on this invention A flowchart showing the basic principle of tact simulation applied to the optimization of component mounting in this embodiment Diagram showing repetitive transition of line tact time calculated by tact simulation Flow chart showing the operation of this embodiment Chart showing example data used to change the component mounting operation on the board Example of data used to change the component mounting operation on the board and explanatory diagram showing how to change

Explanation of symbols

  AC ... Mounting machine

Claims (2)

The production tact time for producing the mounting board by sequentially mounting the components allocated to the plurality of mounting machines that make up the mounting line on the board by using the mounting head by each mounting machine is the target tact set in advance. In the mounting operation optimization method in the mounting line that performs the tact simulation to fit within the time and determines the optimal mounting operation for each mounting machine,
The tact simulation is performed with priority given to simultaneous suction of multiple parts and high-speed movement of the mounting head.
Identify the latest mounting machine that is the bottleneck from the tact time required for each mounting machine by the tact simulation,
For at least one mounting machine other than the slowest mounting machine, at least one of individual suction of a plurality of components and low-speed movement of the mounting head is selected according to the difference in tact time with the slowest mounting machine The mounting operation is optimized in the mounting line, wherein the mounting operation is changed to improve mounting accuracy.   2. The method of optimizing a mounting operation in a mounting line according to claim 1, wherein when changing the mounting operation, a large component is selected with priority given to low-speed movement of the mounting head.

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