The embodiments discussed herein are directed to technology for managing parts.
In the distribution industry or the like, systems using an RFID tag have been developed recently. For example, Japanese Laid-open Patent Publication No. 2005-231882 discloses a developed system that performs an inventory management at a warehouse by attaching an RFID tag to a management box accommodating managed products such as commercial products.
In managing a parts inventory, development of an inventory management system using an RFID tag at a parts warehouse has been underway. However, to accurately manage a parts inventory, it is necessary to manage a parts inventory in a production line as well as at a warehouse. However, in a production line and the like of an information processing device, it is not possible to manage a parts inventory by attaching an RFID tag to each part, from the viewpoint of cost of RFID tags and cost of attaching these tags to parts.
As a result, it is difficult to identify a parts inventory in each production line or at each process of each production line. Consequently, a large amount of time is necessary to check a parts inventory at a time of inventory taking.
According to an aspect of the invention, in a parts management method performed by a parts management device for managing parts used to produce an assembly product, the method includes firstly reading parts identification information and number of parts corresponding to an assembly product of which production is started as used-parts identification information and a used number from a storage device that stores parts constitution information that includes assembly-product identification information identifying an assembly product, parts identification information identifying parts used to produce the assembly product, and number of the parts, by relating these pieces of information to each other, and secondly reading parts container information of a parts container that accommodates parts used for an assembly product of which production is started from a storage device that stores parts container information, for each parts container, including parts identification information of parts accommodated in each parts container and number of the parts by relating these pieces of information to parts-container identification information identifying a parts container, and writing into a storage device, parts container information that includes an updated number of parts obtained by subtracting the number of used parts from number of parts identified by the used-parts identification information read in the firstly reading.
The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.
Exemplary embodiments of a parts management program, a parts management method, and a parts management device according to the present invention will be explained below in detail with reference to the accompanying drawings. In an embodiment of the present invention, a line (production line) includes plural processes, and parts are supplied to each process by plural types of parts supply boxes.
First, an outline of a parts management system according to a first embodiment of the present invention is explained.
As types of supply boxes, there are a supply box to convey only one type of parts, and a supply box to convey plural types of parts necessary to assemble a product. Upon finding an empty supply box in a line, the operator collects the empty box, and carries the box to the parts warehouse.
In the parts management system according to the present embodiment, a UHF-band RFID tag is attached to the supply box. An RFID tag reader is positioned at an exit of the parts warehouse and at an exit of the line, respectively, thereby tracking a movement of the supply box. The parts management system according to the present embodiment stores information of a relationship between the supply box and parts conveyed by the supply box. The parts management system recognizes a movement of parts from the parts warehouse to the line, by tracking a movement of the supply box.
The parts management system according to the present embodiment stores the number of parts accommodated in the supply box taken to the line, and stores information of a relationship between an assembly product, used parts, and the number of the used parts. The number of parts accommodated in the supply box is subtracted corresponding to the number of parts used, by regarding that the parts in the supply box are used when production of the assembly product is started. With this arrangement, the number of off-the-shelf parts in the line is managed at each position.
When the RFID tag reader positioned at the exit of the line reads the RFID tag, the parts management system according to the present embodiment regards that the supply box attached with the read RFID is an empty box. When a number stored as the number of parts accommodated in the supply box is not zero, the parts management system determines that the number of used parts is contradictory, and outputs an alarm. When a time interval from when the number of parts accommodated in the supply box becomes zero until when the supply box is collected as an empty box is longer than a predetermined time, the parts management system determines that the empty box is stagnant in the line, and outputs an alarm.
The parts management system according to the present invention determines whether a time interval of supply boxes is appropriate, based on a time interval of collecting the same type of supply box as an empty box and a time interval from when a supply box is moved to a line until when the number of parts accommodated in this supply box becomes zero. In this case, the same type of supply box means a supply box used to supply the same type of parts (the number of parts types can be singular or plural) to the same process of the same line.
The parts management system according to the present embodiment notifies to a shelf management system that manages shelf information, a state that parts accommodated in the supply box have changed from “off-the-shelf parts” to “product in process” by regarding that the parts in the supply box have been used when production of an assembly product is started. With this arrangement, the parts management system supports asset management by the shelf management system.
As described above, the parts management system according to the present embodiment manages a movement of parts using the UHF-band RFID tag attached to the supply box, and also manages the number of parts for each supply box. As a result, a parts inventory in the line can be accurately managed. When the number of parts in the line is accurately managed, a state of using the parts and a state of supplying the parts can be monitored, and management of shelf information can be supported.
A system configuration of the parts management system according to the present embodiment is explained next.
The maintenance unit 110 is a processor that performs registration, change, and deletion of supply-box master information stored in the supply-box master DB 120, and parts configuration information stored in the parts-configuration-information storage unit 175. The supply-box master information indicates information managed for each type of supply box. The parts configuration information indicates parts used for an assembly product and the number of these parts. The maintenance unit 110 generates initial information of supply-box master information and parts configuration information, respectively using information generated by an initial-data generating unit 11 from a production-BOM master DB 12 of a production management system 10. The maintenance unit 110 registers generated initial information into the supply-box master DB 120 and the parts-configuration-information storage unit 175.
The production-BOM master DB 12 is a database that stores a BOM (bill of material) as parts information for each assembly product.
The maintenance unit 110 writes identification information of a supply box into a UHF-band RFID tag attached to the supply box. The identification information of a supply box includes chart numbers of a line, a process, an address, and a part identifying a type of the supply box, and a serial number of each type of the supply box.
The supply-box master DB 120 is a database that stores supply-box master information.
The registering unit 130 is a processor that generates supply box data to manage each supply box using the supply-box master information stored in the supply-box master DB 120, and registers the generated data into the supply box DB 140.
The supply box DB 140 is a database that stores supply box data.
The tracking unit 150 is a processor that receives information of RFID tags read by the RFID tag readers positioned at the exit of the warehouse and at the exit of the line, respectively and tracks a movement of a supply box. The tracking unit 150 generates a tracking log of the supply box.
The state reflecting unit 160 is a processor that reflects a movement of a supply box into the supply box DB 140 using a tracking log generated by the tracking unit 150. Specifically, the state reflecting unit 160 updates the “state” of supply box data and the “supply date and time”.
The subtracting unit 170 is a processor that receives a production start notification of an assembly product from a progress updating unit 21 of a production management system 20, reads information concerning an assembly product of which production is started from a production order DB 22 updated by the progress updating unit 21, and subtracts the number of used parts from supply box data of a supply box accommodating parts to be used for the assembly product of which production is started.
A supply box Q-Aα-1 and a supply box Q-Aα-2 accommodate four parts Q, respectively. A supply box P-Aβ-1 and a supply box P-Aβ-2 accommodate four parts P, respectively. The “Q-Aα-1” and the like are pieces of information used to identify a supply box, and include information of a part, a line, a process, and a serial number. For example, the “Q-Aα-1” indicates that the part Q is an accommodated part, Aα is an arranged line and an arranged process, and the serial number is 1.
Similarly, a supply box P-Bα-1 and a supply box P-Bα-2 accommodate one part P and four parts P, respectively. A supply box R-Bβ-1 and a supply box R-Bβ-2 accommodate four parts R, respectively. A supply box Q-Bα-1 and a supply box Q-Bα-2 accommodate four parts Q, respectively. A supply box P-Bβ-1 and a supply box P-Bβ-2 accommodate four parts P, respectively.
Upon receiving a notification of a start of production in this state, the subtracting unit 170 specifies items that are used to start the production, that is, a line, a process, and an assembly chart number, with reference to the production order DB 22. The subtracting unit 170 specifies used parts and numbers of the used parts, using the parts configuration information stored in the parts-configuration-information storage unit 175 from the assembly chart number and the process that are specified. The subtracting unit 170 reads from the supply box DB 140 the supply box data of a supply box which first entered the line among supply boxes specified by the line, the process, and the part. The subtracting unit 170 subtracts the number of used parts from the “remaining number”, and writes an updated number after the subtraction into the supply box DB 140 as updated supply box data.
When production using the assembly chart number a is started in the process α of the line A, for example, the subtracting unit 170 specifies the line A, the process α, and the assembly chart number a, with reference to the production order DB 22. The subtracting unit 170 specifies the used part Q and a number “2”, using the parts configuration information stored in the parts-configuration-information storage unit 175 from the assembly chart number a and the process α. The subtracting unit 170 reads from the supply box DB 140 the supply box data of the supply box Q-Aα-1 which first entered the line among supply boxes specified by the line A, the process α, and the part Q. The subtracting unit 170 subtracts the number “2” of used parts from the “remaining number”, and writes an updated number after the subtraction into the supply box DB 140 as updated supply box data.
In this way, the subtracting unit 170 specifies a line, a process, and an assembly chart number which are used to start production, with reference to the production order DB 22. The subtracting unit 170 specifies used parts and numbers of the used parts, using the parts configuration information stored in the parts-configuration-information storage unit 175 from the assembly chart number and the process that are specified. The subtracting unit 170 updates the “remaining number” of the supply box data of the supply box which first entered the line among supply boxes specified by the line, the process, and the part. Accordingly, a parts inventory in the line can be accurately managed.
The subtracting unit 170 updates the last subtraction date and time of the supply box data, with date and time when the “remaining number” of the supply box data is updated. When the subtracting unit 170 updates the last subtraction date and time of the supply box data, the operation monitoring unit 190 can monitor a stagnation of the supply box in the line as described later.
The parts-configuration-information storage unit 175 stores parts configuration information.
The extracting unit 180 is a processor that extracts updated supply box data when the supply box DB 140 is updated, and writes the extracted data as a log into the supply-box-log storage unit 185. That is, when the supply box is moved or when parts in the supply box are used, the extracting unit 180 extracts corresponding supply box data, and writes the data as a log into the supply-box-log storage unit 185.
The supply-box-log storage unit 185 stores a log that the extracting unit 180 extracted from the supply box DB 140, when the supply box DB 140 is updated.
The operation monitoring unit 190 is a processor that monitors a parts supply pace and a state of using parts, by a log written into the supply-box-log storage unit 185, and outputs a parts-supply-pace excessiveness/shortage alarm and an empty-box collection/stagnation/contradiction alarm when necessary.
Thereafter, the operation monitoring unit 190 compares a parts supply interval with “total-number subtraction interval x bin number”. When it is “parts supply interval<total-number subtraction interval×bin number”, the operation monitoring unit 190 determines that a parts supply pace is in excess as compared with a parts using pace, and outputs an excessiveness alarm. When it is “parts supply interval>total-number subtraction interval×bin number +predetermined standard”, the operation monitoring unit 190 determines that a part supply pace is in shortage as compared with a parts using pace, and outputs a shortage alarm.
The operation monitoring unit 190 checks whether a remaining number of the supply box data is zero, when an empty box is collected (exited). When the remaining number is not zero, the operation monitoring unit 190 determines that the empty box is collected although unused parts are remaining in the box, and outputs a contradiction alarm.
When a remaining number of the supply box data is zero and also when a type of movement of tracking log is “entering”, the operation monitoring unit 190 monitors a lapse time from a last subtraction date and time until the current time. When a predetermined time or more has passed, the operation monitoring unit 190 determines that an empty box is not collected although all parts have been used, and outputs a stagnation alarm.
As described above, the operation monitoring unit 190 monitors a parts supply pace and a state of using parts, by a log written into the supply-box-log storage unit 185. The operation monitoring unit 190 outputs a parts-supply-pace excessiveness/shortage alarm and an empty-box collection/stagnation/contradiction alarm when necessary. With this arrangement, a line manager can properly recognize a line state.
The operation monitoring unit 190 monitors a parts inventory for each line, each process, and each supply box using a shelf stock DB 32 managed by a log written in the supply-box-log storage unit 185 and a warehouse management system 30.
The warehouse management system 30 manages a parts inventory in the warehouse and the line. The shelf stock DB 32 is a database that stores information of a parts inventory in the warehouse and the line.
The editing unit 195 edits a log written in the supply-box-log storage unit 185, generates information concerning a movement of parts, and outputs the information to the warehouse management system 30. That is, when a supply box enters a line, the editing unit 195 notifies the warehouse management system 30 that parts accommodated in the supply box are taken from the warehouse and put to the line. When a subtraction of parts is performed, the editing unit 195 notifies the warehouse management system 30 a state that the parts as off-the-shelf parts have changed to a product in process. When the warehouse management system 30 receives the notification concerning the movement of the parts, a movement processing unit 31 reflects the movement to the shelf stock DB 32.
As explained above, the editing unit 195 generates information concerning a movement of parts, and notifies the information to the warehouse management system 30. Accordingly, the warehouse management system 30 can accurately manage a parts inventory including a parts inventory in the line.
A process procedure performed by the parts management system 100 according to the present embodiment is explained next.
As illustrated in
The tracking unit 150 detects entering of the supply box to the line, based on the information that the RFID tag reader positioned at the exit of the warehouse reads from the RFID tag (Step S103). The tracking unit 150 generates a tracking log, and the state reflecting unit 160 updates the supply box DB 140 based on the tracking log (Step S104).
The extracting unit 180 generates an update log of the supply box DB 140, and writes the update log into the supply-box-log storage unit 185. The operation monitoring unit 190 updates a monitoring output based on the update log. The editing unit 195 notifies a movement of the parts to the warehouse management system 30 (Step S105).
Thereafter, when the operation monitoring unit 190 receives a notification of the start of production from the production management system 20 (YES at Step S106), the subtracting unit 170 subtracts the number of parts used for the production and updates the supply box DB 140 (Step S107), and the extracting unit 180 generates an update log of the supply box DB 140 and writes the updated log into the supply-box-log storage unit 185.
The operation monitoring unit 190 updates a monitoring output by the update log, and determines whether the number of parts in the supply box becomes zero. When the number of parts becomes zero, the operation monitoring unit 190 calculates an average value of total-number subtraction intervals, and checks a parts supply pace (Step S108). The editing unit 195 notifies the warehouse management system 30 that the parts are not in the state of off-the-shelf parts (Step S109).
The operation monitoring unit 190 determines whether a supply box is stagnant, based on whether the supply box having no parts is in the state of being in the line during a predetermined time or more. When it is determined that the supply box is stagnant (YES at Step S110), the operation monitoring unit 190 outputs a stagnation alarm (Step S111).
When the tracking unit 150 detects exit of the supply box from the line based on information that the RFID tag reader positioned at the exit of the line read from the RFID tag (Step S112), the tracking unit 150 generates a tracking log. The state reflecting unit 160 updates the supply box DB 140 based on the tracking log (Step S113).
The extracting unit 180 generates an update log of the supply box DB 140, and writes the updated log into the supply-box-log storage unit 185. The operation monitoring unit 190 checks a stagnation of the supply box, and checks a contradiction of the number of parts (Step S114).
As described above, when a movement of the supply box is tracked using an RFID tag and also when the number of parts in the supply box is managed based on a production start notification, a state of using parts in the line can be accurately managed.
A process procedure of the subtraction process depicted in
The subtracting unit specifies a supply box from which the number of parts to be used is subtracted, based on the line, the process, and the parts (Step S203) subtracts the number of parts to be used from the supply box data corresponding to the supply box DB 140, and updates the supply box DB 140 by the current date and time as a last subtraction date and time (Step S204).
As described above, the subtracting unit 170 specifies a supply box from which the number of parts to be used is subtracted based on the production order and the parts configuration information, and updates the corresponding supply box data. With this arrangement, off-the-shelf parts can be accurately managed for each supply box.
As described above, in the present embodiment, the subtracting unit 170 specifies parts used for an assembly product of which production is started, the number of used parts, and a supply box, based on the parts configuration information of the parts-configuration-information storage unit 175 and the production order in the production order DB 22. The subtracting unit 170 subtracts the number of used parts from the number of parts in the supply box data, and updates the supply box DB 140. Therefore, a parts inventory can be accurately managed by the supply box DB 140.
In the present embodiment, the tracking unit 150 detects a supply box entering or exiting the line based on the information of the UHF-band RFID tag. The state reflecting unit 160 reflects a movement of the supply box to the supply box DB 140. Therefore, the tracking unit 150 can accurately manage whether the parts are in the parts warehouse or in the line, by the supply box DB 140.
In the present embodiment, the extracting unit 180 writes the update log of the supply box DB 140 into the supply-box-log storage unit 185. The operation monitoring unit 190 performs monitoring of excessiveness and shortage of the parts supply pace, a stagnation of the supply box in the line, and the number of parts, based on the update log of the supply-box-log storage unit 185. Therefore, the operation monitoring unit 190 can accurately manage the state of using parts in the line.
In the present embodiment, when the parts change from warehouse inventory to a line inventory, and also when the line inventory changes to a product in process, the editing unit 195 notifies the change to the warehouse management system 30 based on the update log of the supply-box-log storage unit 185. Therefore, the warehouse management system 30 can accurately manage the parts inventory including parts inventory in the line.
In the present embodiment, it is explained that the parts management system 100, the production management system 10, the production management system 20, and the warehouse management system 30 are configured as separate systems. However, the present invention is not limited thereto, and can be similarly applied to a case that all or parts of these systems are configured as one system.
In the present embodiment, while the parts management system has been explained, a parts management program having a similar function can be obtained by achieving the configuration held by the parts management system by software. A computer that executes the parts management program is explained below.
The RAM 210 is a memory that stores a program and an intermediate result of execution of the program. The CPU 220 reads a program from the RAM 210 and executes the program. The HDD 230 is a disk device that stores a program and data. The LAN interface 240 connects the computer 200 to other computer via a LAN. The input/output interface 250 connects an input device such as a mouse and a keyboard and a display device. The DVD drive 260 reads and writes a DVD.
A parts management program 211 executed by the computer 200 is stored into the DVD. The DVD drive 260 reads the program from the DVD, and installs the program into the computer 200. Alternatively, the parts management program 211 is stored into a databases of other computer connected via the LAN interface 240, and the program is read from these databases and is installed into the computer 200. The installed parts management program 211 is stored into the HDD 230, and is read by the RAM 210. The CPU 220 executes the read program.
In the above embodiment, it is explained that a supply box is used to convey parts. However, parts can be conveyed in various modes other than using the supply box depicted in
According to one embodiment, parts identification information and the number of parts corresponding to an assembly product of which production is started are read as used-parts identification information and a used number from a storage device that stores parts constitution information that includes assembly-product identification information identifying an assembly product, parts identification information identifying parts used to produce the assembly product, and the number of the parts, by relating these pieces of information to each other. Parts container information of a parts container that accommodates parts used for an assembly product of which production is started is read from a storage device that stores parts container information, for each parts container, including parts identification information of parts accommodated in each parts container and the number of the parts by relating these pieces of information to parts-container identification information identifying a parts container. The parts container information that includes an updated number of parts obtained by subtracting the number of used parts from the number of parts identified by the used-parts identification information is written into the storage device. Therefore, a state of using parts in each parts container can be managed.
According to one embodiment, when a parts container is collected from a production line, parts-container identification information is read from an RFID tag attached to a parts container. It is determined whether the number of parts is zero in the parts container information identified by the read parts-container identification information. When it is determined that the number of parts is not zero, an alarm is output. Therefore, a manager of the production line can check whether parts are properly used.
According to one embodiment, the number of parts after subtracting a used number of parts is set as a new number of parts, and updated parts container information using the current time as a new last subtraction time is written into a storage device. The current time is compared with a stagnation limit time which is obtained by adding a predetermined stagnation limit time to a last subtraction time of the parts container information identified by parts-container identification information read from an RFID tag. When the current time is equal to or larger the stagnation limit time, an alarm is output. Therefore, a manager of a production line can recognize a stagnation state of an empty box.
According to one embodiment, it is determined whether an updated number of parts is zero. When the number of parts is zero, a time measurement is started, and it is determined whether the started measurement time has passed a predetermined time. When the started measurement time has passed the predetermined time, an alarm is output. Therefore, a manager of a production line can recognize a stagnation time of an empty box.
According to one embodiment, when a parts container is taken to a production line by accommodating parts into the parts container by the number of dispatch instruction, parts-container identification information is read from an RFID tag attached to the parts container. A time interval from when the parts-container identification information is read until when the number of parts in the parts container information identified by the parts-container identification information becomes zero is measured as a total-number subtraction interval. A time interval of reading parts-container identification information from the RFID tag at an exit time of the container of the same type of parts is measured as a parts-supply time interval. Whether a parts supply interval is appropriate is determined based on the measured total-number subtraction interval and the parts-supply time interval. When it is determined that the parts-supply time interval is not appropriate, an alarm is output. Therefore, a manager of a production line can recognize whether a parts supply pace is appropriate.
According to one embodiment, parts inventory information in a production line is output based on parts container information of which number of parts is updated. Therefore, a parts inventory in the production line can be easily recognized.
According to one embodiment, parts identification information and the number of parts accommodated in a parts container from which parts-container identification information is read at the time of taking the parts container to a production line are notified as dispatch information to a warehouse management system that manages information of a warehouse that stores the parts. Therefore, the warehouse management system can recognize a movement of parts from the warehouse to the production line.
According to one embodiment, an updated number of parts and parts identification information are notified as product-in-process information to a warehouse management system that manages information of a warehouse that stores the parts. Therefore, the warehouse management system can recognize a state that parts have changed to a product in process.
According to one embodiment, a parts container is configured as a supply box. Therefore, a state of using parts in each supply box can be managed.
According to one embodiment, parts identification information and the number of parts corresponding to an assembly product of which production is started are read as used-parts identification information and a used number from a storage device that stores parts constitution information that includes assembly-product identification information identifying an assembly product, parts identification information identifying parts used to produce the assembly product, and the number of the parts, by relating these pieces of information to each other. Parts container information of a parts container that accommodates parts used for an assembly product of which production is started is read from a storage device that stores parts container information, for each parts container, including parts identification information of parts accommodated in each parts container and the number of the parts by relating these pieces of information to parts-container identification information identifying a parts container. The parts container information that includes an updated number of parts obtained by subtracting the number of used parts from the number of parts identified by the used-parts identification information is written into the storage device. Therefore, a state of using parts in each parts container can be managed.
According to one embodiment, assembly-product identification information identifying an assembly product, parts identification information identifying parts used to produce the assembly product, and the number of the parts are stored, by relating these pieces of information as parts constitution information. Parts identification information of parts accommodated in a parts container and the number of the parts are related to parts-container identification information identifying a parts container, and are stored as parts container information, for each parts container. Parts identification information and the number of parts corresponding to an assembly product of which production is started are read as used-parts identification information and a used number. Parts container information of a parts container that accommodates parts used for an assembly product of which production is started is read. The parts container information is updated by a new number of parts obtained by subtracting the number of used parts from the number of parts identified by the used-parts identification information. Therefore, a state of using parts in each parts container can be managed.
According to one embodiment, because a state of using parts in each parts container is managed, a parts inventory in a production line can be accurately managed.
According to one embodiment, because a manager of a production line can check whether parts are being appropriately used, illegitimate use of parts can be prevented.
According to one embodiment, because a manager of a production line can recognize a stagnation state of an empty box, the production line can be improved.
According to one embodiment, because a manager of a production line can recognize whether a parts supply pace is appropriate, the production line can be improved.
According to one embodiment, because a parts inventory in a production line can be easily recognized, checking of a parts inventory at a time of inventory taking can be performed in a short time.
According to one embodiment, because a warehouse management system can recognize a movement of parts from a warehouse to a production line, an inventory at a parts warehouse can be accurately managed.
Further, according to one embodiment, because the warehouse management system can recognize a state that parts are changed to a product in process, a parts inventory can be accurately managed.
All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present inventions have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.
Number | Date | Country | Kind |
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2006-265888 | Sep 2006 | JP | national |
This application is a continuation of PCT international application Ser. No. PCT/JP2007/59988 filed on May 15, 2007 which designates the United States, incorporated herein by reference, and which claims the benefit of priority from Japanese Patent Application No. 2006-265888, filed on Sep. 28, 2006, the entire contents of which are incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/JP2007/059988 | May 2007 | US |
Child | 12408688 | US |