JPH11291144A - Inspection lot control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection lot control system for improving the inspection accuracy, in a machining production line consisting of plural machining processes. SOLUTION: A machining production line consisting of plural machining processes 1-4 is provided with watching means 9-12 for watching the work state of a facility in respective machining processes, setting means 5-8 for setting the process condition of the facility in respective processes, process information acquisition means 13-16 for acquiring the process information in response to the process condition of the facility in respective machining processes, detection means 21-24 for detecting the work on the machining production line, memory means 29, 31 for memorizing the production state of the detected work and a sorting means 25 for sorting the inspection lot of the work produced in the machining production line by the production state of the detected work. Thereby, the work is sorted by the sorting means 25 according to the memory content of the memory means 29, 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection lot management system for improving inspection accuracy in sampling inspection of a produced work in a processing production line including a plurality of processing steps.

[0002]

2. Description of the Related Art Conventionally, as a method of inspecting a work as a result of the processing in a machining production line which usually includes a plurality of machining steps, a 100% inspection, a sampling inspection and the like are known. As for the use of inspection methods,
For example, when starting up a production line such as when a new product is produced or when a production location is changed, a 100% inspection is performed to inspect all the produced workpieces. When the production line is gradually stabilized by production, generally, a sample is extracted from the produced work according to a predetermined rule, and the process shifts to a sampling inspection for inspecting only the sample and judging the quality of the entire work. . Normally, at a production site, management is performed on a lot basis consisting of an arbitrary number of workpieces out of all the produced workpieces. In a sampling inspection, several workpieces are inspected from a lot to be inspected (inspection lot). Sampling inspection is performed by extracting as a sample.

[0003]

However, in the above-mentioned sampling inspection, the production line is usually
Since there are many factors that affect the quality of workpieces, such as equipment trouble, maintenance, and switching of process conditions during product switching, even in the same inspection lot when performing sampling inspection, the above factors are different from each other. Work produced in (production line environment) is mixed. For this reason, there is a problem that the accuracy of the sampling inspection is reduced. The present invention has been made in order to solve the conventional problems as described above, and it is an object of the present invention to provide an inspection lot management system that improves inspection accuracy in a processing production line including a plurality of processing steps. Aim.

[0004]

According to a first aspect of the present invention, there is provided an inspection lot management system comprising a plurality of processing steps.
Monitoring means for monitoring the operation status of the equipment in each processing step, setting means for setting the process conditions of the equipment in each processing step, and process information acquisition for obtaining process information corresponding to the process conditions of the equipment in each processing step Means, detection means for detecting a work on the processing production line, means for storing the detected production state of the work, and sorting of the inspection lot of the work produced on the processing production line according to the detected production state of the work. It is characterized by having sorting means. According to a second aspect of the present invention, in the inspection lot management system according to the first aspect, the sorting means sets a sorting rule at the time of sorting to IF-THEN.
The inspection lots are stored in a format and the sorting rules are applied to sort the inspection lots. The invention of claim 3 is
2. The inspection lot management system according to claim 1, wherein the sorting rule includes an event of occurrence of equipment maintenance in each of the processing steps. According to a fourth aspect of the present invention, in the inspection lot management system of the first aspect, the sorting rule includes an event of occurrence of an equipment error. According to a fifth aspect of the present invention, in the inspection lot management system of the first aspect, the sorting rule includes a type change event. According to a sixth aspect of the present invention, in the inspection lot management system of the first aspect, the sorting rule includes an event of a change in a process condition. According to a seventh aspect of the present invention, in the inspection lot management system according to the first aspect, the inspection lot sorting rule is applied to the equipment in each of the processing steps before transferring the work, and the work being processed is automatically performed. It is characterized by being removed.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on illustrated embodiments. FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. In FIG. 1, the flow of a workpiece processed and produced at each of the processing stations 1 to 4 includes a processing station 1 to a processing station 2,
The order is from the processing station 2 to the processing station 3, and finally the work is sorted for each inspection lot via the inspection lot sorting station 25.
The processing stations 1 to 4 set predetermined processing conditions based on the processing instruction data stored in the processing instruction data storage devices 5 to 8 provided in each processing station,
Processing is performed according to the processing conditions. In addition, equipment operation status monitoring devices 9-1 provided in the respective processing stations 1-4.
2 monitors the operation status of each processing station 1-4. The process information acquisition devices 13 to 16 acquire process information corresponding to the processing conditions (process conditions) of the equipment in each of the processing stations 1 to 4. Information input device 17-
Reference numeral 20 is provided for inputting maintenance information and type switching information performed in each of the processing stations 1 to 4. The work detecting devices 21 to 24 detect the input and discharge of the work in each of the processing stations 1 to 4. The processing instruction data storage devices 5 to 8, the equipment operation status monitoring devices 9 to 12, and the process information acquisition devices 13 to
16, the information input devices 17 to 20, the work detection devices 21 to 24, and the inspection lot sorting station 25 for sorting the work processed in the processing station 4 for inspection are controlled through a communication line 26. Device 27
Connected to.

The control device 27 detects a flow of a work on a production line (hereinafter, referred to as tracking), a work tracking unit 28, and each station 1 of each work.
, A work input / discharge time storage unit 29 for storing the input and output times to and from an inspection lot, an inspection lot sorting rule 30 for sorting into inspection lots, an event such as an error occurrence / return at the processing stations 1 to 4, and the event of the event. An event storage unit 31 for storing occurrence times as events, an inference engine unit 32 for determining an inspection lot, the work tracking unit 28, a work input / discharge time storage unit 29, an inspection lot sorting rule 30, an event storage unit 31, an inference engine The control unit 33 controls the unit 32. The information input device 34 and the information output device 35 are connected to the control device 27, and display and edit the inspection lot sorting rule 30 by the information input device 34 and the information output device 35.

Here, the operation in the configuration of FIG. 1 will be described. When a workpiece is loaded into the processing station 1, the workpiece tracking unit 28 is notified of the loading of the workpiece by the workpiece detection device 21. When the work input is notified, the work tracking unit 28
A virtual work model is generated, and tracking of the work is started. Along with the start of the work tracking, a memory area for the work is secured in the work input / discharge time storage unit 29, and the work input time of the work to the processing station 1 is stored. The work is transferred to the processing station 2 when the processing in the processing station 1 is completed. However, when the work is discharged from the processing station 1, the discharge of the work is detected by the work detection device 21 in the work tracking unit. 28 is notified. In response to the notification, the discharge time of the work from the processing station 1 is stored in the work input / discharge time storage unit 29. Similarly, the processing is performed while the work is transferred from the processing station 2 to the processing station 4, and finally the inspection lot sorting station 2
At the time when the work is loaded into the work 5, the loading and discharging times of the work at each station are stored in the work loading / discharging time storage unit 29. If an event related to maintenance, an error, a type change, a change in a process condition, or the like occurs in each of the processing stations during the operation of the production line, the station No. that occurred, the content of the event, and the occurrence time are indicated by an event. It is stored in the storage unit 31. The events are reported to the equipment operation status monitoring devices 9 to 12, process information acquisition devices 13 to 16, and information input devices 17 to 20.
And so on. When the work is put into the inspection lot sorting station 25, the inference engine unit 32 determines which inspection lot the work belongs to.

FIG. 2 shows an embodiment of an inspection lot sorting rule for sorting works at an inspection lot sorting station, which is stored in an IF-THEN format. The inference engine 32 uses the inspection lot sorting rule 30 as shown in FIG. 2 to store the event data stored in the event storage 31 and the work input / discharge time storage 29 for each work. The input and discharge time data at each station are associated with each other, and the above-described classification and integration of the fact data are performed for each work, and it is determined which inspection lot the work belongs to.

The above determination method will be described in more detail with reference to FIGS. FIG. 3 is a diagram in which the input time and the discharge time of each of the four (W1 to W4) works at each station and the time at which an event occurs at each station are represented in a time series. In FIG. 3, for example, a work W2 is put into the station 1 at a time tl, discharged from the station 1 at a time t2,
At time t3, the station 2 is loaded, and at time t4, station 2 is discharged. Further, for example, in the station 1, an error of the error code 100 occurs at time t5, and returns at time t6. On the other hand, in the station 4, the maintenance of the maintenance code 101 occurs at time t7 and ends at time t8.
Although the above data is represented in a diagram format in FIG. 3, data actually stored in the work input / output storage unit 29 and the event storage unit 31 is stored as numerical data. .

FIGS. 4 and 5 show how the rule of FIG. 2 is applied to the case of FIG. FIG. 4 and FIG.
FIG. 4 is a diagram in which, as in FIG. 3, the loading / unloading time at each station of each work and the event occurrence time are represented in time series. In FIG. 4, when an error occurs in the station 1, each work is input / output at each station.
The discharge time and the event occurrence time are expressed in chronological order. In FIG. 5, when an error occurs in the station 1 and the maintenance occurs in the station 4, the input / discharge time of each work in each station, And, the event occurrence time is expressed in a time series. In FIG. 4, as shown in FIG.
The figure shows a case where an error of 0 occurs at time t5 and returns at time t6. In this case, the rule relating to the error code 100 in the station 1 is searched by the inference engine unit 32 from the inspection lot sorting rules 30 in FIG. Then, as a result of the execution of the applicable rule in the inspection lot sorting rule 30, the work processed in the station 1 is one inspection lot (inspection lot 2) from time t5 to t6 + sl.
The workpieces processed at the station 1 before and after that are treated as an inspection lot 1 and an inspection lot 3, respectively. The time s1 is a time for stabilizing the processing of the work after the occurrence of the event and the return, and for example, an inspection result at the time of 100% inspection or a statistical time at the time of production of the same kind of work in the past. It is set according to various inspection results.

FIG. 5 shows a case where the maintenance of the maintenance code 101 occurs at time t7 and ends at time t8 in the station 4 separately from the error in the station 1 as shown in FIG. . In that case, from the inspection lot sorting rule 30 of FIG.
The rules related to the maintenance code 101 in the station 4 are searched by the inference engine unit 32.
Then, as a result of the execution of the applicable rule in the inspection lot sorting rule 30, the work processed in the station 4 from time t7 to t8 s4 is treated as one inspection lot. The time of s4 is also a time for stabilizing the processing of the work after the occurrence of the event and the return, similarly to the time of s1 described above. It is set based on statistical inspection results and the like during the production of the same kind of work. However, in the case of FIG. 5, since the inspection lot generated due to the error of the station 1 and the inspection lot generated due to the maintenance of the station 4 partially overlap, the overlapped lot is treated as another inspection lot. Therefore, in the case of FIG. 5, five inspection lots from the inspection lot 1 to the inspection lot 5 shown in FIG. 5 are generated.

As described above, if each group is classified as one inspection lot like the five inspection lots shown in FIG. 5 and the sampled one of the inspection lots is set as the inspection target, the same applies. The work produced in the production state (processing state, process state) is gathered in the same group, and the inspection is performed by sampling from each group, so that the inspection accuracy is improved. An instruction to remove a work from a station on the production line is described in the THEN section of the IF-THEN rule, and the inference engine unit 32 is activated when the work is transferred between stations. Thus, the work to be transferred can be automatically removed from the production line. In that case, since unnecessary work can be removed from the inspection lot in advance, the efficiency of the inspection can be increased, and finally the efficiency of the production can be increased.

[0013]

As described above, according to the first aspect of the present invention,
In a production line, when inspecting a produced work by sampling, it is possible to construct a system for improving the inspection accuracy. According to the second aspect of the present invention,
The rules for sorting into inspection lots can be confirmed with a text image, and can be easily edited. According to the third aspect of the present invention, it is possible to sort the inspection lots depending on whether or not the maintenance of the equipment is affected in each processing step. According to the fourth aspect of the present invention, it is possible to sort the inspection lots depending on whether or not an error of the equipment occurs in each processing step. According to the fifth aspect of the present invention, it is determined whether or not each processing step is affected by the type change.
Inspection lots can be sorted. According to the sixth aspect of the present invention, it is possible to sort inspection lots depending on whether or not each processing step is affected by a change in process conditions. According to the present invention, since unnecessary work can be removed from the inspection lot in advance, production efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 shows an embodiment of an inspection lot sorting rule for sorting works at an inspection lot sorting station, which is stored in an IF-THEN format.

FIG. 3 shows input and output times at each station of processed workpieces of four (W1 to W4) workpieces, and
FIG. 6 is a diagram expressing the occurrence time of an event in each station in a time series.

FIG. 4 is a diagram showing, in an chronological order, a loading / unloading time and an event occurrence time of each work in each station when an error occurs in the station 1;

FIG. 5 is a diagram showing, in chronological order, the input / output time of each work and the event occurrence time at each station when an error occurs in the station 1 and maintenance occurs in the station 4.

[Explanation of symbols]

1-4 processing station, 5-8 processing instruction data storage device, 9-12 equipment operation status monitoring device, 13-16 process information acquisition device, 17-2
0: Information input device, 21 to 24: Work detection device, 25: Inspection lot sorting station, 26:
..Line, 27 ... control device, 28 ... work tracking unit, 29 ... work input / discharge time storage unit
Reference numeral 30: inspection lot sorting rule, 31: event storage unit, 32: inference engine unit, 33: control unit, 34: information input device, 35: information output device, W1 W4: Work, t1 to t8: Time,
s1, s4 ... time

Claims (7)

[Claims] In a machining production line composed of a plurality of machining steps, monitoring means for monitoring the operation status of equipment in each of the machining steps, setting means for setting process conditions of the equipment in each of the machining steps, Process information acquisition means for acquiring process information corresponding to the process conditions of the equipment in the machining process, detection means for detecting a work on the processing production line, storage means for storing a production state of the work detected by the detection means, An inspection lot management system, comprising: sorting means for sorting inspection lots of the work produced on the processing production line according to the production state of the work detected by the detection means. 2. The inspection according to claim 1, wherein the sorting means stores the sorting rules for the sorting in an IF-THEN format, and sorts the inspection lots by applying the sorting rules. Lot management system. 3. The inspection lot management system according to claim 1, wherein the sorting rule includes an event of occurrence of equipment maintenance in each of the processing steps. 4. The inspection lot management system according to claim 1, wherein the sorting rule includes an event of occurrence of an equipment error. 5. The inspection lot management system according to claim 1, wherein the sorting rule includes a type change event. 6. The inspection lot management system according to claim 1, wherein the sorting rule includes an event of a change in a process condition. 7. The apparatus according to claim 1, wherein the inspection lot sorting rule is applied to the equipment in each of the processing steps before transferring the work, and the work being processed is automatically removed. Inspection lot management system.