Method of and device for collecting knowledge of molding technique

A method of and a device for collecting knowledge of an injection molding technique capable of collecting knowledge of an injection molding technique from a number of expert engineers without a knowledge engineer and also collecting machine operation data obtained in performing an injection molding operation in accordance with the knowledge of the injection molding technique. A plurality of injection molding machines are connected to a server computer through a network such as LAN. A predetermined rule for collecting an expert engineer's knowledge of the injection molding technique is stored to be executable in the server computer. Each of the injection molding machines is provided with an input device for allowing an operator to input data utilizing the predetermined rule. When a problem such as a molding defect occurs in an injection molding machine, an expert engineer takes countermeasure such as modification of set values of molding conditions against the molding defect. The items of the modified conditions, the set values of the molding conditions before and after the modification by the expert engineer and machine operation data before and after the modification of the molding conditions are sent to the server computer to be stored. Thus, the knowledge of the appropriate countermeasure which the expert engineers have and the actual machine operation data before and after taking the countermeasure are stored in the server computer, so that qualitative and quantitative data are utilized for finding an appropriate countermeasure against the molding defect.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 4 shows a basic arrangement of a device for collecting knowledge of the molding technique according to an embodiment of the present invention. Injection molding machines 2 - 1 to 2 -N on which knowledge of the injection molding is collected are connected to a computer 1 as an information processing device having a server function through a communication line 4 of a network such as LAN (local area network). The server computer 1 is provided with a rule for collecting knowledge of the molding technique which expert engineers have, as a hearing algorithm prepared by a knowledge engineer. Respective injection molding machines 2 - 1 to 2 -N have input/output devices 3 - 1 to 3 -N to function as clients of the server computer 1 . The server computer 1 executes the hearing algorithm, and expert engineers E- 1 to E-N input data and knowledge through the input/output devices 3 - 1 to 3 -N according to the hearing algorithm, to collect the knowledge in the server computer 1 . Thus, the input/output devices 3 - 1 to 3 -N constitute means for executing man-machine interface according to the hearing algorithm. The server computer 1 stores the collected knowledge and data in a storage device 5 . The server computer 1 is connected with storage devices 6 , 7 and 8 for storing molding defects data, resin data, molds data, etc. The knowledge which a plurality of expert engineers E- 1 to E-N have can be simultaneously collected effectively based on the hearing algorithm since the plurality of injection molding machines are connected to the server computer 1 through the LAN 4 . FIG. 5 shows an example of the hearing algorithm for collecting knowledge from expert engineers. When a problem against which a countermeasure has to be taken such as a molding defect occur, the hearing algorithm is executed. First, the molding conditions presently set to an injection molding machine and data of a machine operation under the present molding conditions when the molding defect occurred are sent to the server computer 1 (Step A 1 ) and stored with associated file names in a data table T 4 , as shown in FIG. 11 . The molding conditions comprise a name of molds, a name of resin in use, an injection condition, a metering condition, a clamping condition, etc. and these data are stored as molding conditions before countermeasure with an associated file name BCO. The machine operation data including time of obtaining the data, the number of shots, a cycle time period, an injection time period, a metering time period, mold opening and closing time periods, an ejection time period, a peak pressure, a cushion amount, the minimum cushion amount, temperature data No. 1-No. 6, . . . are stored in a machine operation data table T 3 in the injection molding machine, as shown in FIG. 10 . The machine operation data are sent to the server computer 1 through the network 4 and stored in the collected data table T 4 as machine operation data before countermeasure with an associated file name BMO, as shown in FIG. 11 . Then, it is determined whether finding of a countermeasure for the molding defect is carried out for the first time, or finding of the countermeasure is carried out for the second or more times as a continued processing to find an appropriate countermeasure on a mold, resin, peripheral equipments, etc. other than the molding conditions after failing in eliminating the molding defect by adjusting the molding conditions (Step A 2 ). In this embodiment, a countermeasure factor of “molding conditions” is always selected for the first determination of a countermeasure and therefore for the first time of determination, the countermeasure factor of “molding conditions” is automatically selected in Step A 2 . A table T 1 listing items of categorized molding detects against one of which a countermeasure has to be taken is stored in advance, as shown in FIG. 8 . The stored table T 1 is displayed to prompt an operator, i.e. an expert engineer to select one of the items in the table (Step A 3 ). It is determined whether or not one of the items is selected by the operator (Step A 4 ) and if one of the items is selected, the selected item is sent to the server computer 1 to be stored in the collection data table T 4 (Step A 5 ). In this example, “short shot” is selected as an item of molding defect against which a countermeasure has to be taken. Then, a table T 2 storing items of countermeasure conditions (“molding conditions” in this example) to be modified for the selected item of the molding defect (“short shot” in this example) is displayed to prompt the operator to select one of the molding conditions (Step A 6 ). An example of the table T 2 is shown in FIG. 9 where items of the molding conditions for the selected molding defect of “short shot” are displayed. In this example, “1. injecting condition”, “2. metering condition”, “3. clamping condition”, “4. ejecting condition”, “5. temperature condition”, . . . are displayed as the conditions to be modified. When one of the conditions is selected by the operator, i.e., expert engineer (Step A 7 ), the present set values of the selected condition are displayed on the display device (Step A 8 ). The expert engineer modifies the set value of the selected condition and inputs an input completion command. The set value modified by the expert engineer is stored (Step A 9 ) and when the manual input operation is completed (Step A 10 ), the item of the modified molding condition and the modified value thereof are sent to the server computer 1 (Step A 11 ). The server computer 1 stores the received data in the collected data table T 4 as the modified condition data with a file name BCO. The set values of the whole molding conditions including the modified set value of the selected molding condition may be stored as the modified molding condition data, or only the item of the modified molding condition and the modified value thereof may be stored. A message to prompt the operator (expert engineer) to perform a test shot is displayed (Step A 12 ) and when the test shot is completed the controller of the injection molding machine sends the machine operation data in the machine operation data table T 3 stored in performing the test shot to the server computer 1 , and the server computer 1 stores the received data as machine operation data after modification with an associated fine name AMO in the collected data table T 4 (Step A 14 ). Then, the expert engineer observes and evaluates the molded product to determine whether the molded product is 1) deteriorated, 2) unchanged, 3) improved, 4) non-defective, or 5) to be subjected to modification of another molding factor (Step A 15 ). The expert engineer selects one of the above items. If one of the items 1)-3) is selected, the procedure proceeds from Step A 15 to Step A 6 where another molding condition is selected to be modified by the expert engineer. Then, the processing of the subsequent Steps A 7 -A 14 are executed to obtain the modified molding condition data (ACO) of the set value of the newly selected molding condition, the machine operation data after modification of the molding condition (AMO) and the obtained data are stored in the collected data table T 4 . In the same manner, if one of the items 1)-3) is selected, the processing of Step A 6 -A 14 is repeatedly executed so that the molding condition data after countermeasure and the machine condition data after countermeasure are stored with associated file names in the collected data table T 4 . On the other hand, if the expert engineer determines that the molding defect can not be eliminated by only modification of the molding conditions and selects the item 5 ) of modification of another molding factor, a signal indicating continued processing of finding countermeasure is sent to the server computer 1 to store data indicating “continued processing” at an item “continued/completed” (Steps A 17 , A 18 ). If the expert engineer determines that the molded product is non-defective and selects the item 4 ), a completion signal is sent to the server computer 1 to store data indicating “procedure completed” at the item “continued/completed” (Step A 19 ). In the case of performing the continued processing, the procedure proceeds from Step A 2 to Step A 20 to perform the continued processing as shown in FIG. 6 . In the continued processing, items of 1) countermeasure on mold, 2) countermeasure on resin, 3) countermeasure on peripheral equipments are displayed on the display device to prompt the expert engineer to select one of the items (Step B 1 ). After one of the items is selected (Step B 2 ) and a countermeasure of the selected item is carried out (Step B 3 ), the selected item and contents of the countermeasure are sent to the server computer 1 and stored in the collected data table T 4 . FIG. 7 shows an example of the countermeasure on the mold. Items of 1) countermeasure on gates, 2) performing maintenance of gas vent, 3) changing of design of gas vent, 4) changing of design of cavity, 5) other countermeasures are displayed to prompt the expert engineer to select one of the items (Step C 1 ). After one of the items is selected (Step C 2 ) and a countermeasure of the selected item is carried out, the selected item and contents of the countermeasure are sent to the server computer 1 and stored in the collected data table T 4 (Step C 3 ). As described, a manual operation by an operator of an expert engineer on the basis of the expert engineer's knowledge for taking countermeasure against a problem such as a molding defect is automatically collected and stored in the server computer at the occurrence of the problem, so that the knowledge which the expert engineers have is effectively collected. Further, the set values of the molding conditions and the actual machine operation data before and after the modification for the countermeasure on each molding defect are stored, and thus appropriate countermeasures against respective problems can be taken referring to the stored qualitative and quantitative data. Thus, an expert system of high efficiency is built up.