JP2009110435A - Conveyance bottleneck analysis device for production line - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conveyance bottleneck analysis device for production line, which checks, with respect to a production line in which a workpiece is carried between a plurality of manufacturing devices through a plurality of carrying device, the state of a relay table that is a delivery point between the carrying devices, and detects a bottleneck of a carrying system from state information of the relay table adjacent to the carrying devices. <P>SOLUTION: Workpiece carrying-in waiting time data A for a workpiece to reach a relay table 4a between carrying devices after reserving it, relay table reservation waiting time data B for the workpiece to reserve a next relay table 4b after it is carried therein, workpiece carrying-out waiting time data C for the workpiece to be carried out from the current relay table 4a after reserving the next relay table 4b, and next workpiece reservation waiting time data D for a next workpiece to reserver the relay table 4a after the current workpiece is carried out are collected, the state of the relay tables is determined from the collected time data, and a conveyance bottleneck is detected from the state of the relay table adjacent to the carrying devices. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention includes a plurality of production apparatuses, and an apparatus for analyzing a conveyance bottleneck of a production line causing a production delay in a production line that conveys a workpiece between a plurality of conveyance apparatuses via a relay stand About.

  In the production activities of factories that produce products such as liquid crystals and semiconductors, in general, a workpiece in the middle of production is transferred from a production process to the next production process by transferring it between multiple transfer devices via a relay stand. Is producing. In this case, even if the work in the other production process is completed in a short time, the product is not produced unless the work in the specific production process proceeds. The productivity of the production line is determined by the processing capability of the production process or the capability of the transfer device that transfers the production process to the transfer process via the relay board. In this specification, the case where the productivity of the production line is reduced due to the processing capacity of the production process is called a process bottleneck, and the conveyance capacity of the conveyance device that conveys from the production process to the conveyance process via the relay stand The case where the productivity of the production line is reduced due to this is called a conveyance bottleneck.

  In order to improve the productivity of a production line in a production line equipped with multiple production devices and transporting workpieces between multiple transfer devices via a relay stand, the bottleneck is produced. Measures that can improve performance are required.

  A technique for identifying a bottleneck in a production line having a plurality of production apparatuses has been proposed. For example, Patent Literature 1 below discloses a technology that supports a process of identifying a production facility that is a bottleneck in a production line in which a plurality of production facilities are arranged in series. In the technique described in Patent Document 1, the operating time and the non-operating time are detected for each facility constituting the production line. Furthermore, based on the operation status of the upstream production facility and the downstream production facility, the detected non-operation time is calculated as the time when the workpiece has not been carried in from the upstream side, Classify the time when the workpiece is not in operation because it cannot be detected. According to this technology, based on the operation rate of each production facility and the positional relationship of each production facility in the production line, a work non-operation time is created in the upstream production facility, and no work in the downstream production facility. The process that creates the operating time can be identified as the bottleneck process.

Patent Document 2 below discloses a technique for searching for a production process that is a bottleneck in a production line in a production line having a plurality of production processes. In the technique described in Patent Document 2, the standby time of the transfer device for each process is accumulated from the operation state and position information of the work transfer device, and the production process that becomes a bottleneck in the production line from the accumulated wait time Can be searched.
JP 2004-246404 A (Toyota Motor Corporation) “Production Line Analysis Device” JP 2007-52623 A (Toyota Motor Corporation) “Method and apparatus for searching for bottleneck production process in production line”

  According to the technology described in Patent Document 1, as described above, a plurality of production facilities are connected in series from the availability of individual production facilities constituting the production line and the positional relationship of the production facilities in the production line. It is possible to analyze the operating status of the production lines that are arranged. By performing such an analysis, it is possible to identify a production process that is a bottleneck. However, in the technique described in Patent Document 1, for example, a production process in which a plurality of production facilities of the same type are arranged in parallel and a longer processing time than other production processes is required. In a production line that installs multiple production facilities in parallel and advances production activities in parallel to improve the production line, identify the production process that is the process bottleneck from the operating state of each production facility I can't do it.

  Further, according to the technique described in Patent Document 2, as described above, the process bottleneck can be specified by analyzing the operation status of the work transfer device. However, the technique described in Patent Document 2 detects a bottleneck process in a flow shop type production line. For example, the production apparatus is distributed like a job shop type production line in a liquid crystal factory or the like. In addition, a conveyance bottleneck or a process bottleneck that is a bottleneck of a conveyance system in a production line that is conveyed via a plurality of conveyance devices cannot be detected.

  In addition, the transport capacity of the transport system depends not only on the transport capacity (operation status) of the transport device, but also on the capacity of the relay stand (the number of platforms on which the work can be placed on the relay stand connecting the transport devices). . Therefore, in order to detect the bottleneck of the transfer system, it is necessary to verify the transfer capability of the relay stand. For this reason, the technology described in Patent Document 2 cannot detect a transport bottleneck.

  Therefore, the present invention can analyze the time of a workpiece passing through a relay table, which is a transfer point between a plurality of transfer devices, and thereby, transfer that is a bottleneck even in a job shop type production line It is an object of the present invention to provide a transport bottleneck analysis device for a production line that can specify a device.

  In order to solve the above-described problems, the present invention is a bottleneck analysis apparatus that analyzes a bottleneck of a transport apparatus of a production line that includes a plurality of production apparatuses and transports workpieces between a plurality of transport apparatuses. The workpiece loading waiting time data until the workpiece arrives at the upstream relay table after the workpiece has reserved the upstream relay table installed in the transfer unit between the transfer devices, and the workpiece is on the upstream side Waiting table reservation waiting time data from when it is loaded into the relay station until the next downstream relay station is reserved, and work unloading from when the work reserves the downstream relay station to when the upstream relay board is unloaded Data collection means for collecting waiting time data and next work reservation waiting time data from when the work is unloaded from the upstream relay board until the next work reserves the upstream relay board; Time data storage means for storing time summary data obtained by aggregating the time data collected by the data collection means, and relay stand status determination means for judging the state of each relay stand from the time summary data stored in the time data storage means And a relay stand state data storage means for storing a result determined for each relay stand by the relay stand state determining means.

In the transport bottleneck analysis apparatus for production lines according to the present invention, the following specific modes can be exemplified.
(A) A mode in which the relay stand state determination means detects a transport bottleneck from the state of all the relay stands stored in the relay stand state data storage means,
(B) The time data storage means classifies and stores the collected time data for each relay stand into four types, and stores the time data cumulatively while updating the time data,
(C) A mode in which the attendant console state determination means determines the state of the attendant by calculating the stored time data as percentage time data and comparing it with a percentage threshold value,
(D) an aspect comprising display output means for displaying and outputting time data collected by the data collection means;
(E) an aspect comprising means for detecting the operation rate of the transport device from the time data collected by the data collecting means;
(F) A mode provided with a display output means for displaying and outputting the state of the relay stand determined by the relay stand state determining means,
(G) A mode in which at least two of the modes (a) to (f) are combined.

  According to the conveyance bottleneck analysis device for a production line according to the present invention, even if it is a job shop type production line by analyzing the time of a workpiece passing through a relay stand that is a transfer point between a plurality of conveyance devices. It is possible to identify a transport device that is a bottleneck. It can also be introduced into a simulation model. In this case, since the conveyance bottleneck can be automatically detected, it is possible to shorten the simulation examination time.

  In addition, as in the aspect (a), the occurrence of a conveyance bottleneck can be specified in the entire production line by monitoring the state of all stored relay stands.

Moreover, by classifying and storing the collected time data for each relay stand into four types of relay stand states as in the above-described aspect (b), for example, the following (A) to (C) It becomes possible to recognize. That is,
(A) When the work carry-in waiting time data is long: The work on the upstream side is busy.
(B) When the relay table reservation waiting time data is long: Since the next relay table is not free, the capacity of the downstream relay table is insufficient. Alternatively, the work on the downstream side of the relay table is busy.
(C) When the workpiece unloading waiting time data is long: The downstream workpiece transfer is busy.
(D) When the next work reservation waiting time data is long: There is a margin in the work transfer capacity.

  Further, as in the above-described aspect (c), by calculating the stored time data as percentage time data, the state of the relay board can be determined from this ratio.

  In addition, as in the above-mentioned aspect (d), by displaying the collected time data, the operator can grasp the situation of each relay stand and use it as a judgment material when estimating the position of the transport bottleneck. it can.

  Moreover, it can be set as the material at the time of detecting the bottleneck of a conveying apparatus by detecting the operation rate of a conveying apparatus from the collected time data like the aspect of said (e). This is because a transport device having a higher operating rate than other transport devices tends to have a higher possibility of a transport bottleneck.

  Moreover, the operator can specify the position of the transport bottleneck in the production line by displaying the state of the relay stand as in the mode (f).

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, the following embodiment is an example which actualized this invention, Comprising: The thing of the character which limits the technical scope of this invention is not.

  FIG. 1 shows a system configuration of a transport system including a transport bottleneck analyzer according to an embodiment of the present invention.

  This transport system includes a transport bottleneck analyzer 1a, a network 1b, a plurality of relay stands 1c (4a, 4b,...), And a display function 1d (5a, 5b,. …). The transport bottleneck analyzer 1a, the plurality of relay stations 1c, and the display function 1d are each connected to a network 1b.

  The transport bottleneck analyzer 1a includes a time data collection unit 3a that collects time breakdown information of the plurality of relay tables 1c, and a relay table time information database that stores time data collected by the time data collection unit 3a. 2a. The transport bottleneck analysis apparatus 1a stores relay table state determination unit 3b that determines the state of the relay table based on data in the relay table time information database 2a, and data of the relay table state determination unit 3b. And an attendant table database 2b. Here, the relay stand state determination unit 3b determines the transport bottleneck of the production line from the state data of all the relay stands stored in the relay stand state database 2b. Further, the transport bottleneck analysis apparatus 1a may include a relay table time breakdown display unit 3c that gives an instruction to display time data used for determination by the relay table state determination unit 3b on a layout.

  That is, the transport bottleneck analysis device 1 a includes a processing device 3 and a storage device 2. The processing device 3 includes the time data collection unit 3a that functions as a data collection unit and the relay table state determination unit 3b that functions as a relay table state determination unit. The processing device 3 may be configured to include the relay table time breakdown display unit 3c. In this case, the relay table time breakdown display unit 3c and the display function 1d function as display output means. The storage device 2 includes the relay table time information database 2a that functions as a time data storage unit, and the relay table state database 2b that functions as a relay table state data storage unit.

  The time data collection unit 3a is a workpiece loading waiting time data from when the workpiece has reserved an upstream relay station installed in a workpiece transfer unit between transfer devices until the workpiece arrives at the upstream relay table, Waiting table reservation waiting time data from the time when the work is carried into the upstream side relay stand until the next downstream side relay stand is reserved, and the current time after the work reserves the next downstream side relay stand. Work unloading waiting time data until unloading of the upstream relay stand and next work reservation waiting time data from when the work is unloaded from the upstream relay stand until the next work reserves the upstream relay stand Collect as 4 types of time data.

  Here, the relay table time information database 2a stores the time data collected by the time data collection unit 3a for each relay table while cumulatively updating (accumulating) the data.

  The relay table state determination unit 3b calculates percentage data from the time data in the relay table time information database 2a, determines the state of the relay table, and stores the result in the relay table state database 2b. This flow will be described later using the flowchart of FIG.

  Here, when the relay stand state determination unit 3b detects a transport bottleneck, the problem location of the transport device and all the relay stands connected to the transport device is detected from the data result of the relay stand state database 2b. To do. This detection rule will be described later with reference to FIG.

  FIG. 2 is a schematic diagram showing a layout of the transport system shown in FIG. As shown in FIG. 2, for example, in a production line including a plurality of production apparatuses such as liquid crystals and semiconductors, a plurality of transfer apparatuses 6 a, 6 b, 6 c,. Products are produced by transporting workpieces via

  FIG. 3 is a diagram for explaining the breakdown of the time during which the workpieces 1, 2,... Pass through the relay board 4a. The code A (A1, A2,...), The code B (B1, B2,...), The code C (C1, C2,...), And the code D (D1, D2,...) Shown in FIG. The four types of time data collected by the part 3a are shown. That is, the reference symbol A (A1, A2,...) Indicates that the workpieces 1, 2,... Reserve the upstream relay table 4a between the transfer devices 6a, 6b and then the workpieces 1, 2,. The workpiece carry-in waiting time data 7a until it arrives at is shown. Symbol B (B1, B2,...) Indicates relay table reservation waiting time data 7b from when the workpieces 1, 2,... Are loaded into the upstream relay table 4a until the next downstream relay table 4b is reserved. ing. Symbol C (C1, C2,...) Indicates workpiece unloading waiting time data 7c from when the workpieces 1, 2,... Reserve the next downstream relay stand 4b to when the current upstream relay stand 4a is unloaded. ing. In addition, reference sign D (D1, D2,...) Indicates a period from when the workpieces 1, 2,... Are unloaded from the upstream relay table 4a to when the next workpieces 2, 3,. The next work reservation waiting time data 7d is shown. The sum of the waiting times of the symbols B and C is the time during which the work is present on the upstream relay stand 4a, the waiting time of the symbol A indicates the time that is being transported by the transfer device 6a, and the waiting time of the symbol D is the repeater stand The time when the transport device 6a on the upstream side of 4a is not operating is shown. The time data A, B, C, and D are generated for each work, and the relay table time information database 2a is updated each time.

  FIG. 4 is a diagram illustrating an example of a processing flow for determining the state of the relay board. In the flowchart shown in FIG. 4, step S01 shows the movement of the time data collection unit 3a. In this step S01, the state of the relay stand is divided into a work loading waiting time Ai (i is an integer of 1 or more), a data relay stand reservation waiting time Bi, a data work unloading waiting time Ci, and a data next work reservation waiting time data Di. taking measurement. When the relay table is a relay table on which a plurality of works can be placed, time data is measured for each relay point of the relay table. The operating rate of the transfer device may be detected from the time data collected by the time data collection unit 3a.

  In step S02, when the number of relay points at which the time data can only be measured for the next work reservation waiting time data D is greater than a preset threshold value Se when the relay table is a relay table on which a plurality of works can be placed. Moves to step S03, and if it is less than or equal to the preset threshold value Se, moves to step S04. In step S03, the state of the target relay stand is determined as the first relay stand state Fd and stored in the relay stand state database 2b.

In step S04, the time data Ai, Bi, Ci, Di (i = 1 to n: n) collected in step S01 are used within the period necessary for the analysis using the integration formulas of the following formulas (1) to (4). The number of works collecting data) is stored in the relay table time information database 2a while cumulatively updating the data A, B, C, D. Note that the definition of the period required for analysis differs depending on the analysis purpose, and the start and end of data collection may be arbitrarily set.
A ← A + Ai (1)
B ← B + Bi (2)
C ← C + Ci Expression (3)
D ← D + Di (4)
In step S05, the period required for the analysis is determined. If the period is insufficient, the process proceeds to step S01, and the steps for the analysis period are repeated from step S01. When the repetition for the analysis period is completed in step S05, the process proceeds to step S06.

  In step S06, the total time of the workpiece loading waiting time data A, relay table reservation waiting time data B, workpiece unloading waiting time data C, and next workpiece reservation waiting time data D stored in the relay table time information database 2a. The percentages Pa, Pb, Pc, and Pd of the time data A, B, C, and D are calculated from the data as a percentage, and the process proceeds to step S07. In addition, when the target relay stand is a relay stand that can place a plurality of workpieces, here, the work loading waiting time data A, the relay stand reservation waiting time data B, the work unloading waiting time stored for each relay point. The weight C of the data C and the next work reservation waiting time data D is calculated, and the ratio Pa, Pb, Pc, Pd of the time data A, B, C, D is similarly calculated as a single relay stand as a percentage, and the process proceeds to step S07. .

  In step S07, the percentage Pd of the next work reservation waiting time data in the percentage value calculated earlier is compared with the threshold value Sd set in advance for each relay console. If the ratio Pd is larger than the preset threshold value Sd, the process proceeds to step S08, and if not, the process proceeds to step S09. In step S08, the state of the target relay stand is determined as the first relay stand state Fd, and is stored in the relay stand state database 2b.

  In step S09, the ratio Pb of the relay console reservation waiting time data is compared with the threshold value Sb set for each relay console in advance. If the ratio Pb is larger than the preset threshold value Sb, the process proceeds to step S10, and if not larger, the process proceeds to step S11. In step S10, the state of the target relay stand is determined as the second relay stand state Fb, and is stored in the relay stand state database 2b.

  In step S11, the ratio Pc of the workpiece carry-out waiting time data is compared with the threshold value Sc set in advance for each relay board. If the ratio Pc is greater than the preset threshold value Sc, the process proceeds to step S12, and if not greater, the process proceeds to step S13. In step S12, the state of the target relay stand is determined as the third relay stand state Fc, and is stored in the relay stand state database 2b.

  In step S13, the ratio Pa of the workpiece carry-in waiting time data is compared with the threshold value Sa set for each relay board in advance. If the ratio Pa is greater than the preset threshold value Sa, the process proceeds to step S14, and if not greater, the process proceeds to step S15. In step S14, the state of the target relay stand is determined as the fourth relay stand state Fa, and is stored in the relay stand state database 2b. On the other hand, in step S15, the state of the target relay stand is determined to be the fifth relay stand state Fe and stored in the relay stand state database 2b. The above processing is performed for all the relay boards in the production line.

  FIG. 5 is a graph showing an example of the breakdown of the operation ratio of the relay console 4a. The ratio of the time data stored in the relay console time information database 2a is represented by a graph.

  As a characteristic of this graph, when the ratio Pa of the work carry-in waiting time data in the graph occupies a high ratio in the whole, it is considered that the transport device 6a on the upstream side of the relay stand 4a is rate-limiting. Similarly, if the proportion Pb of relay table reservation waiting time data occupies a high ratio in the whole, the next relay table 4b is not free. That is, the transport device 6c downstream from the relay stand 4b is rate-limiting. Or it is thought that the downstream relay stand including the relay stand 4b is insufficient. If the ratio Pc of the workpiece unloading waiting time data is high in the whole, it is considered that the transport device 6b on the downstream side of the relay stand 4a is rate-limiting. Further, if the ratio Pd of the next work reservation waiting time data occupies a low ratio, there are many works passing through the relay stand 4a, and it is considered that the operating rate of the transfer device upstream of the relay stand 4a is high and busy. .

  FIG. 6 is a diagram illustrating an example of a processing flow for detecting the rate-limiting state of the transport device 6b and the shortage state of the relay stand from the states of the front and rear relay stands 4a and 4b.

  In the flowchart shown in FIG. 6, in step S21, the states of the relay stands 4a and 4b before and after the transport device 6b are read from the relay stand state database 2b, and the process proceeds to step S22. The following steps S22 to S32 are an operation flow in which the relay stand state determination unit 3b detects a transport bottleneck.

  That is, in step S22, the use states of the upstream relay stand 4a immediately before the transport device 6b read out in step S21 and the downstream relay stand 4b immediately after the transport device 6b are compared. At this time, if the downstream relay stand 4b after the transfer device 6b is in the fourth relay stand state Fa and the previous upstream relay stand 4a is in the third repeater stand state Fc, step S23 is performed. If this condition is not satisfied, the process proceeds to step S24. In step S23, it is determined that the transport device 6b is rate limiting. Here, the transport apparatus determined to be transport-limited is a transport bottleneck in the production line.

  In step S24, from the information read in step S21, the state of the downstream relay stand 4b after the transport device 6b is the second relay stand state Fb, and the state of the previous upstream relay stand 4a is the second relay stand. When it is in the state Fb, the process proceeds to step S25, and when this condition is not satisfied, the process proceeds to step S26. In step S25, it is determined that the downstream transfer device including the transfer device 6b is rate limiting, or the downstream relay stand that does not include the downstream relay stand 4b is insufficient.

  In step S26, from the information read in step S21, the state of the downstream relay stand 4b after the transport device 6b is the fifth relay stand state Fe, and the state of the previous upstream relay stand 4a is the second relay stand. When it is in the state Fb, the process proceeds to step S27, and when this condition is not satisfied, the process proceeds to step S28. In step S27, it is determined that the downstream relay stand 4b after the transfer device 6b is insufficient.

  In step S28, from the information read in step S21, the state of the downstream relay stand 4b after the transport device 6b is the first relay stand state Fd, and the state of the previous upstream relay stand 4a is the fifth relay stand. When it is in the state Fe, the process proceeds to step S29, and when this condition is not satisfied, the process proceeds to step S30. In step S29, it is determined that the upstream relay stand 4a in front of the transport device 6b is insufficient.

  In step S30, from the information read in step S21, the state of the downstream relay stand 4b after the transport device 6b is the first relay stand state Fd, and the state of the previous upstream relay stand 4a is the first relay stand. When it is in the state Fd, the process proceeds to step S31, and when this condition is not satisfied, the process proceeds to step S32. In step S31, it is determined that the transport device 6b is not rate-limiting. On the other hand, in step S32, the transfer device 6b and the front and rear relay stands 4a and 4b are terminated without determining whether the rate is limited or insufficient. The above processing is performed for all the conveyance devices existing in the production line, and the conveyance bottleneck of the production line is detected.

  FIG. 7 shows the determination results stored in the relay table status database 2b on the layout.

  Since the front upstream relay stand 4a is in the third relay stand state Fc and the subsequent downstream relay stand 4b is in the fourth relay stand state Fa, the user can visually confirm that the transport device 6b is rate-limiting. Can be identified. “Fc” on the upper left side of the transfer device 6b and “Fa” on the upper left side of the transfer device 6c in FIG. 7 indicate the state of the relay stand used by the work heading from the transfer device 6a to the transfer device 6b and the transfer device 6b. The state of the relay stand used by the work heading to the transfer device 6c is shown. On the other hand, “Fc” on the lower left side of the transfer device 6c and “Fa” on the lower left side of the transfer device 6b indicate the case where the workpiece is directed from the transfer device 6c to the transfer device 6b and from the transfer device 6b to the transfer device 6a. The state of the relay stand used by the work heading from the transport device 6c to the transport device 6b and the state of the relay stand used by the work heading from the transport device 6b to the transport device 6a are shown.

  Further, the ratio of the time data stored in the attendant console time information database 2a can be displayed on the layout for all attendant consoles in the form of an operation ratio breakdown graph as shown in FIG. In this case, the user can read the tendency of the production line by comparing the ratio of the state of the front and rear relay stand. For example, in the case of the transport device 6b, when the rate Pa of the work loading waiting time data of the previous upstream relay stand 4a is smaller than the rate Pa of the work loading waiting time data of the subsequent downstream relay stand 4b, the further the downstream the closer to the downstream It can be inferred that it tends to be rate limiting.

  FIG. 8 shows one embodiment of the present invention. In the example shown in FIG. 8, the transfer device 6b connected to the relay stands 4a and 4b is connected to two facilities 8a and 8b. In such a layout, the time data B for the relay table is the relay table or facility reservation from when the work is carried into the upstream relay table 4a until the next downstream relay table 4b or the facilities 8a and 8b are reserved. The waiting time data is defined as the waiting time data, and the time data C is the work unloading waiting time data from the time when the work reserves the next downstream relay stand 4b or the equipment 8a, 8b until the current upstream relay stand 4a is unloaded. And can be determined by the state determination flowchart of the relay stand in FIG.

  FIG. 9 shows another embodiment of the present invention. In FIG. 9, one of a plurality of transfer devices 6a, 6b, 6c, and 6d is connected to one relay table 4b along the circumferential direction, and the other of the plurality of transfer devices is the other relay table. In this example, the other of the transfer device 6a is connected to the relay stand 4a, the other of the transfer device 6b is connected to the relay stand 4c, the other of the transfer device 6c is connected to the repeater stand 4d, and the other of the transfer device 6d is connected to the repeater stand 4e. is doing. As for the flow of the line, the relay bases 4a and 4c are located upstream of the relay base 4b, and the relay bases 4d and 4e are located downstream of the relay base 4b.

  When the work is carried from the upstream relay stand 4a, 4c to the downstream relay stand 4b, the time data is collected by the upstream relay stand 4a, 4c and collected by the time data collecting unit 3a, You may memorize | store in the said attendance stand time information database 2a. In this case, in the state determination flowchart of the relay stand in FIG. 4, time data A4a from when the work reserves the upstream relay stand 4a until the work arrives at the upstream repeater 4a, and the work is the upstream repeater stand. The sum of the time data A4c from when the work 4c is reserved until the work arrives at the upstream side relay stand 4c can be used as the work carry-in waiting time data A to determine the state of the relay stand.

  Further, when the work is carried out to the downstream relay stand 4d, 4e with respect to the upstream relay stand 4b, the time data C is converted into time data C4d and time data C4e for the downstream relay stand 4d, 4e, respectively. It may be separately collected by the time data collection unit 3a and stored in the relay table time information database 2a. In this case, in the relay state determination flowchart of FIG. 4, the time data C4d from when the work reserves the downstream relay stand 4d to the unloading of the upstream relay stand 4b and the work reserves the downstream relay stand 4e. The state of the relay stand can be determined using the sum of the time data C4e from the time until the upstream relay stand 4b is taken out as the work carry waiting time data C.

  The collection of the time data A and the time data C described above may be divided and collected by the number of connected transfer apparatuses. The time data subdivided and collected is the work loading waiting time data A subdivided and stored in the relay table time information database 2a when detecting the transport bottleneck in the flowchart for detecting the transport bottleneck in FIG. By using the workpiece unloading waiting time data C subdivided and stored in the relay table time information database 2a, the ratio between the upstream transfer devices 6a and 6b connected to the relay table 4b may be referred to. Thus, the ratio between the downstream side transfer devices 6c and 6d connected to the relay stand 4b may be referred to.

  FIG. 10 shows still another embodiment of the present invention. In the example shown in FIG. 10, transfer devices 6a and 6b are respectively connected to both sides of one relay stand 4c. One transfer device 6a includes a plurality of relay stands 4a and 4c, and the other transfer device 6b includes It is connected to a plurality of relay stands 4d and 4e. As for the flow of the line, the relay boards 4a and 4b are located upstream of the relay board 4c, and the relay boards 4d and 4e are located downstream of the relay board 4c. When there is a predetermined transfer device for the relay stand as shown in FIG. 10, the state of the relay stand can be determined according to the relay stand state determination flowchart shown in FIG.

  FIG. 11 shows still another embodiment of the present invention. FIG. 11 shows a transport system layout when the relay table has a relay table on which a plurality of workpieces can be placed. Thus, the relay stand that can be used in the present invention may be capable of placing a plurality of workpieces.

  The relay stand 4b having the layout shown in FIG. 11 can place a plurality of works, and the works can be placed at the relay points 9a and 9b. Also for the relay stand 4b, the state of the relay stand can be determined according to the relay stand state determination flowchart shown in FIG. In the state determination flowchart of the relay stand shown in FIG. 4, when the relay stand can place a plurality of works, the state is determined as one relay stand by taking a weighted average for each relay point. This method is not limited only to the weighted average, and the time data may be corrected using a threshold set in advance for each relay console. For relay points of the same relay console, other than the target relay point may be reserved. A method may be used in which the period of the state is considered as outside the time data.

  Furthermore, in the state determination flowchart of the relay stand shown in FIG. 4, when the relay stand can place a plurality of works, if there is a relay point whose time data is only the next work reservation waiting time data D, relay is performed. Although the state of the stand is determined to be the first attendant stand state Fd, the state of the attendant stand is also determined when any time data of a plurality of repeater points is the next work reservation waiting time data D in the entire analysis period. May be determined as the first relay stand state Fd.

  The transport bottleneck analysis apparatus according to the present invention can be introduced into a simulation model. FIG. 12 is a schematic block diagram showing an example of a simulation system in which the conveyance bottleneck analysis apparatus according to the present invention is introduced.

  A simulation system 100 illustrated in FIG. 12 includes a simulation execution unit 110 and a transport bottleneck analysis device 120. The simulation execution unit 110 executes a production simulation of a production line that performs work transfer between a plurality of transfer apparatuses via a relay stand, and has a display function for displaying the state of the relay stand on the layout. . The conveyance bottleneck analysis apparatus 120 is connected to the simulation execution unit 110 and includes an evaluation data calculation unit 121, a conveyance information collection unit 122, and a display unit 123.

  The evaluation data calculation unit 121 has a configuration corresponding to the time data collection unit 3a and the relay table state determination unit 3b of the conveyance bottleneck analysis apparatus 1a illustrated in FIG. 1, and the conveyance information collection unit 122 is illustrated in FIG. The configuration corresponds to the relay table time information database 2a and the relay table status database 2b of the transport bottleneck analyzer 1a. The display unit 123 has a configuration corresponding to the relay table time breakdown display unit 3c of the transport bottleneck analysis apparatus 1a shown in FIG.

  According to the transport bottleneck analysis device 120, the transport bottleneck can be automatically detected by executing the processes shown in FIGS. 4 and 6 in the production simulation executed by the simulation execution unit 110. Therefore, it is possible to shorten the time for examining the conveyance bottleneck in the simulation.

The system block diagram of the conveyance system provided with the conveyance bottleneck analysis apparatus which concerns on embodiment of this invention. Schematic which shows the layout of the conveyance system shown in FIG. Explanatory drawing of the breakdown of the time when the work passes through the relay board. The flowchart which shows an example of the state determination processing flow of a relay stand. The graph which shows an example of the operation ratio breakdown of a relay stand. The flowchart which shows an example of the detection process flow of a conveyance bottleneck. Layout showing the status of the attendant console. The transfer system layout when the transfer device carries workpieces into the equipment. Transport system layout when multiple transport devices are connected to one relay stand. A transport system layout when a transport device connected to multiple relay stands is connected to one relay stand. Conveyance system layout including a relay stand that can place multiple workpieces. 1 is a schematic block diagram illustrating an example of a simulation system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a ... Conveyance bottleneck analysis apparatus, 1b ... Network, 1c ... Relay stand, 1d ... Relay stand status display function, 2a ... Relay stand time information database, 2b ... Relay stand status Database, 3a... Time data collection unit, 3b... Relay table status determination unit, 3c .. relay table time breakdown display unit, 4a, 4b, 4c, 4d, 4e .. relay table, 5a, 5b ... Relay stand status display function, 6a, 6b, 6c, 6d ... Conveying device, 7a, 7b, 7c, 7d ... Time data, 8a, 8b ... Equipment, 9a, 9b ... Relay point

Claims (7)

A bottleneck analyzer that analyzes a bottleneck of a transport device of a production line that includes a plurality of production devices and transports a workpiece via a plurality of transport devices,
Workpiece loading waiting time data from when the workpiece reserves the upstream relay stand installed in the transfer unit between the transfer devices to when the workpiece arrives at the upstream relay stand, and the workpiece on the upstream relay stand Waiting table reservation waiting time data from when it is loaded until the next downstream relay stand is reserved, and workpiece unloading waiting time data from when the work reserves the downstream relay stand to when the upstream relay stand is carried out Data collection means for collecting next work reservation waiting time data until the next work reserves the upstream relay board after the work is unloaded from the upstream relay board;
Time data storage means for storing time total data obtained by totaling the time data collected by the data collection means;
Relay station state determination means for determining the state of each relay board from the time summary data stored in the time data storage means,
A transport bottleneck analysis device for a production line, comprising: relay table state data storage means for storing a result determined for each relay table by the relay table state determination means.   2. The transport bottleneck of a production line according to claim 1, wherein the relay stand state determination unit detects a transport bottleneck from the states of all the relay stands stored in the relay stand state data storage unit. Analysis device.   The time data storage means classifies and stores the collected time data for each relay stand into four types, and performs storage while updating the time data cumulatively. Production bottleneck analyzer for production line.   4. The relay stand state determination means determines the state of a relay stand by calculating the stored time data as percentage time data and comparing it with a percentage threshold value. Conveyor bottleneck analysis device for production lines described in 1.   5. The production line transport bottleneck analysis apparatus according to claim 1, further comprising display output means for displaying and outputting time data collected by the data collection means.   6. The transport bottleneck analysis apparatus for a production line according to claim 1, further comprising means for detecting an operation rate of the transport apparatus from the time data collected by the data collection means.   7. The transport bottleneck analysis device for a production line according to claim 1, further comprising display output means for displaying and outputting the state of the relay board determined by the relay board state determining means.

Images