JPH02128822A - Method and apparatus for setting optimum monitor tolerant value of injection molding machine - Google Patents

Abstract

PURPOSE:To easily set an optimum monitor tolerant value within a short time by correcting an execution monitoring tolerant value on the basis of the correlational graph of the measured value of a nondefective molded product and each nondefective product monitoring data value. CONSTITUTION:When the molding of a product is completed, various monitoring data values in an injection process are inputted to the monitoring data memory 66 of a control unit 42 from an input circuit 46 through a data bus 76 by a controller. At the same time, the wt., dimension and other items of a molded product are automatically measured to be inputted to a molded product measuring memory 68 from the input circuit 46 through the data bus 76. Next, the quality of the product is judged and the measured data of the nondefective molded product is inputted to a function operator 72 along with monitoring data to calculate a correlation Y=f(X) and this correlation is displayed on the picture of a CRT 56 as a correlational graph. On the basis of this correlational graph, a tolerant value is corrected while the picture of the CRT is looked by a keyboard.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method and apparatus for setting optimum monitoring tolerance values for an injection molding machine, and particularly relates to a statistical method and apparatus for setting monitoring data values during injection molding and measured values of a molded product. By grasping the correlation,
An optimal monitor for injection molding machines that allows you to easily set monitor tolerance values for molding non-defective products by correcting and setting the tolerance values of each monitoring data value to the appropriate tolerance values relative to the tolerance values of measured values for non-defective molded products. TECHNICAL FIELD The present invention relates to a tolerance value setting method and device.

[Conventional technology] As automatic control of injection molding machines is progressing through computerization, etc., depending on the set molding conditions, a large number of defective products may be produced, so the quality of these products must also be automatically managed. In particular, in order to maintain product quality in each process of injection molding, factors that are directly related (molding conditions, etc.) and the operating status of the injection molding machine (molding process) must be maintained. ) It is necessary to control the various factors above.

In injection molding, the injection process, which directly determines the quality of the molded product, is divided into three processes: filling, pressure holding, and cooling/solidification.In addition to these three steps, plasticization of the material in the heating cylinder There are processes such as conversion and measurement.

Program control of the injection process controls the state of the molten material to shape the quality of the molded product during each process such as plasticizing and kneading the molding material, filling the molten material into the mold, and subsequent cooling and solidification. It is controlled so that it is optimal for

In other words, the program control currently in practical use includes injection speed control, injection pressure (holding pressure) control, cavity internal pressure control, automatic switching control from injection speed control to injection pressure, and cushion amount control. control, plasticization/metering process control, mold clamping process control, etc.

Such various controls are optimally controlled to a predetermined value by constantly comparing a permissible value preset in the control device with an execution monitoring value.

However, suitable tolerances cannot always be obtained for molded products depending on the setting conditions in the molding process, and the molding setting tolerances must be corrected. Therefore, the actual values such as filling time, metering time, cushion position, injection start position, screw rotation speed, and barrel temperature in the injection molding process are monitored in the control device, and the measured values of the molded product ( In relation to f! amount and fl! value, tolerance values for various moldings to obtain good products were empirically determined and manually set on a display device.

[Problem to be solved by the invention] However, when a product defect occurs, the operator manually corrects and sets the tolerance values for various moldings while observing the measured values of the molded product, which takes time. During this period, the machine is stopped, which reduces the operating rate and impairs productivity.In addition, the molding conditions are determined empirically and there are individual differences, resulting in a lack of versatility.

Therefore, the purpose of the present invention is to find a statistical correlation between the measured values of non-defective molded products and various non-defective product monitoring data values,
Based on the graph of this correlation, it is possible to modify the execution monitoring tolerance value during injection molding, and furthermore, by determining the calculation formula from the correlation and manually or automatically setting the tolerance value of the monitoring data value, it is possible to produce good products. An object of the present invention is to provide a method and apparatus for setting optimal conditions for an injection molding machine, which can easily modify execution monitoring tolerance values for molding within a short time.

[Means for Solving the Problems] In order to achieve the above-mentioned object, in the present invention, a permissible value is determined from monitoring data values sampled by a control device during the molding process of an injection molding machine and measured values of a molded product. In the method for setting the optimal monitoring tolerance for an injection molding machine that performs injection molding, the statistical correlation between the measured values of the molded product and the various monitoring data values described above is determined. The present invention is characterized in that an arithmetic expression is obtained from , this arithmetic expression is stored in a storage medium, and is displayed as a graph on a display device, and based on this correlation graph, an execution monitoring tolerance value during injection molding is corrected and a non-defective product is determined.

Further, the optimum monitor tolerance value setting method according to the present invention determines the tolerance value from the monitoring data values sampled by the control device during the molding process of the injection molding machine and the measured values of the molded product, and performs the monitoring corresponding to this. In the method of correcting the tolerance value and setting the optimal monitor tolerance value for an injection molding machine that performs injection molding, an arithmetic expression is determined from the statistical correlation between the measured values of the molded product and the various monitoring data values, and the method is used to determine the quality of the non-defective molded product. The calculation formula and the tolerance value are stored in a storage medium, the correlation is displayed on a display device along with the tolerance value, and the monitoring data for the non-defective measurement tolerance of the molded product is calculated based on the calculation formula. It is characterized by automatically setting tolerance values, monitoring execution monitoring tolerance values during injection molding, correcting them, and determining non-defective products.

Furthermore, the optimum monitor tolerance value setting device according to the present invention determines a correlation between the measured values of a molded product molded by an injection molding machine and monitoring data values sampled during injection molding, and performs execution based on this correlation. In the optimal monitor tolerance setting device for an injection molding machine, which corrects the monitoring tolerance and sets the optimal monitor tolerance to control injection, a device is installed at each predetermined position of the injection molding machine to detect the injection status during the injection molding process. A detection section provided, an automatic measuring device that measures the injection molded product, a drive control section that controls each drive section of the injection molding machine, and the tolerance values for execution monitoring sampled from the detection section are input. and a control device that outputs command signals processed based on tolerance values to each of the drive control units, and the control device outputs measurement values of non-defective molded products measured by the automatic measurement device and monitoring data values corresponding thereto. a non-defective product data storage unit that stores the non-defective molded product measurement value and the non-defective product monitoring data value, a function calculation unit that calculates an arithmetic expression from the statistical correlation between the non-defective molded product measurement value and the non-defective product monitoring data value, and a display device that displays the correlation on a screen as a graph; and a calculation unit that compares and calculates the permissible values and monitoring permissible values of the measured values of the molded product measured based on the calculation formula and the sampled execution monitoring permissible values, and based on the graph displayed on the display device. The present invention is characterized in that an optimum monitoring tolerance value is set by modifying the execution monitoring tolerance value monitored.

Further, the optimum monitor tolerance value setting device according to the present invention determines a correlation between the measured value of a molded product molded by an injection molding machine and the monitoring data value sampled during injection molding, and performs execution based on this correlation. In the optimum monitoring tolerance setting device for an injection molding machine that corrects the monitoring tolerance and sets the optimal monitor tolerance to control injection, the device adjusts the monitoring tolerance to each predetermined part of the injection molding machine to detect the injection status during the injection molding process. A detection section provided, an automatic measuring device that measures the injection molded product, a drive control section that controls each drive section of the injection molding machine, and the tolerance values for execution monitoring sampled from the detection section are input. a control device that outputs a command signal processed based on a tolerance value to each of the drive control units; a non-defective product data storage unit that stores monitoring data values sampled from the non-defective molded product, a function calculation unit that calculates an arithmetic expression from the statistical correlation between the non-defective molded product measurement value and the non-defective monitoring data value, A display device that displays the graph above and a calculation that converts the acceptable value of the measured value of the non-defective molded product into an acceptable value of the monitoring data value based on the above calculation formula, and compares the sampled execution monitoring acceptable value with this acceptable value. It consists of a calculation unit that automatically sets the monitoring tolerance value converted by this calculation unit, and a tolerance value setting unit that automatically sets the monitoring tolerance value converted by this calculation unit, and corrects the monitored execution tolerance value based on the graph and tolerance value displayed on the display device. The method is characterized in that the optimum monitor tolerance value is set by

[Function] According to the optimal condition setting and device for the injection molding machine according to the present invention, during injection molding, statistical correlations between the measured values of a non-defective molded product and various non-defective product monitoring data values are determined,
This is displayed in a graph on a display device, and based on this correlation graph, the execution monitoring tolerance sampled during injection molding can be easily corrected.

Furthermore, an arithmetic expression is determined from the above correlation, and based on this arithmetic expression, the allowable value of the monitoring data value is set manually or automatically with respect to the statistically determined allowable value of the non-defective molded product, and this is displayed on the display device along with the graph. The execution monitoring tolerance value during injection molding can be corrected based on the correlation graph and the tolerance value, and the i-suitable monitoring tolerance value can be easily set within a short time.

[Example] Next, an example of an optimum monitoring tolerance setting method and apparatus for an injection molding machine according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of the method and apparatus for setting optimum monitor tolerance values for an injection molding machine according to the present invention, and reference numeral 10 indicates an injection molding machine, and this injection molding machine has a barrel 12 and , a screw 14 inserted into the barrel 12 so as to be rotatable and movable in the axial direction, and the screw 1
It basically consists of a pair of injection cylinders 18 that drive the screw 14 forward and backward in the axial direction via a bearing unit 16, and a hydraulic motor 20 that rotationally drives the screw 14. The molten resin is melted by the heat of the heater provided in the mold 12 and the shear heat generated by the rotation of the screw 14, and the molten resin reaches a predetermined amount and is filled into the mold 22 by the injection cylinder 18 via the screw 14. The molded product molded by pressurized filling of the molten resin is automatically taken out of the machine by releasing the mold 22 by the mold clamping device 24.

The hydraulic motor 20, injection cylinder 18, and mold clamping device 24, which are drive units, control the rotational speed of the screw 14 by controlling servo valves 26, 28, and 30, respectively, as drive control units.
The moving speed of the injection cylinder 18, the opening/closing position, opening/closing speed, etc. of the mold clamping device 24 are controlled.

Further, detection units for detecting the injection state are provided at predetermined positions of the injection molding machine.

That is, the hydraulic motor 20 is provided with a sensor 32 (for example, a rotary encoder, a tachogenerator, a potentiometer, etc.) that detects rotation, and the bearing unit 16 is provided with a position sensor 34.3 that detects its movement position.
6 (for example, a limit switch, a proximity switch, a magnetic scale, etc.), and the injection cylinder 18 is also provided with a pressure sensor 38 for detecting injection pressure. Further, a temperature sensor 40 is provided on the injection side wall of the barrel to detect the temperature of the molten resin within the barrel.

On the other hand, 42 indicates a control device, 44 is a central processing unit (hereinafter referred to as CPU) of the control device 42, and 46 is an input circuit connected to each of the above-mentioned sensors, in which execution data values monitored during the injection molding process are stored. is input.

48 is an output circuit, and servo valves 26, 28, and 30, respectively.
It is connected to an alarm output device 50 and a timer 52, and a signal processed within the control device is output.

56 is an input device (hereinafter referred to as a keyboard) 56 for manually inputting setting values, etc., and 60 is a CRT control circuit that controls a display device (hereinafter referred to as CRT) 58.

Further, 62 indicates a storage unit (storage device) which is a storage medium, and this storage device is a non-defective product data storage unit (non-defective product) that stores measurement values and monitoring data values of each molded product during molding of non-defective products, and their tolerance values. data memory) 64, a monitoring data memory 66 that stores various execution monitoring data values in the injection process inputted from the input circuit 46 and their calculated tolerance values, and an automatic weighing device and dimensions for weighing the weight etc. of the product. The total W of the molded product measured by an automatic measuring device 54 consisting of an automatic measuring device etc.
J lia is inputted from the input circuit 46, and the molded product measurement memory 68 calculates and stores the tolerance value from this, and statistically determines the tolerance value of the molded product measurement value and monitoring data value when molding a non-defective product, and calculates the tolerance value. Along with setting,
A tolerance value setting unit (tolerance value setter) 70 is provided which automatically sets a corrected tolerance value by comparing it with an execution monitoring tolerance value in a calculation unit to be described later.

Furthermore, a function calculation unit (function calculation unit) 7 calculates an operational formula from the statistical correlation between the measured values and monitoring data values of the non-defective molded products stored in the non-defective product data memory 64.
2 and the correlation graph obtained by this function calculator as C
The CRT control circuit 60 displayed on the R7 screen and this CR
7 A keyboard 56 for comparing the monitoring tolerance value and the execution monitoring tolerance value based on the correlation graph displayed on the screen and manually inputting and correcting the values on the screen, and an execution monitoring tolerance value stored in the monitoring data memory 66. and the tolerance value stored in the tolerance value setter 70 based on the correlation graph to obtain a corrected tolerance value, and a calculation unit 70 that determines whether each execution monitoring data value is within the tolerance value or not. configured.

In this case, execution monitoring data during injection molding is always monitored by the calculation unit 70, and if the execution monitoring data is outside the allowable value, an alarm is output from the alarm output circuit 5o via the output circuit 48.

The address data bus 76 is used in all the controllers mentioned above.
It is connected to the CPU via the CPU, and data is processed here.

Next, the correlation graph displayed on the CR7 screen will be explained below with reference to FIGS. 2 and 3.

That is, in the graph shown in Fig. 2, the vertical axis Y shows the measured values of the molded product (weight, dimensions, etc.), and the horizontal axis shows the monitoring data values (filling time, lightening time, unloading time, etc.).
Cycle time, cushion time, FPC switching position, injection start position, screw rotation speed, barrel temperature, etc.), statistical correlation graph for molding good products Y = f
(X) is displayed.

However, based on this graph, each monitoring data value in the injection process can be compared with the measured value of the injection molded product, and corrections can be made on the screen so that the value is a non-defective value.

Also, by using the arithmetic formula to obtain the graph shown in Figure 2, CR
Molded product measurement tolerance ΔY based on the graph displayed on T
The permissible range ΔX is automatically set, and the execution monitoring permissible value is compared with this permissible value and corrected manually or automatically, thereby setting the optimal monitor permissible value (FIG. 3).

Next, the operation of the embodiment of the present invention will be explained based on the flowchart shown in FIG.

That is, when the product molding is completed in step 1, the control device inputs various monitoring data values in the injection process from the input circuit 46 to the monitoring data memory 66 of the control device 42 via the data bus 76 in step 2. At the same time, in step 3, the weight, dimensions, etc. of the molded product are automatically measured and input from the input circuit 46 to the molded product measurement memory 68 via the data bus 76. Next, in step 4, the quality of the product is determined, and the measurement data of the non-defective molded product is transferred to step 5 together with the monitoring data of step 2, and the function calculator 72 calculates the correlation Y=f (X
) is determined and displayed as a correlation graph on the screen of the CRT 56 in step 6.

Next, in step 7, it is selected whether to set the allowable value automatically or manually, and in the case of manual setting, in step 8, the allowable value is corrected using the keyboard 56 based on the correlation graph while looking at the CRT screen.

If automatic is selected, the calculation unit calculates the allowable value of the product data measurement value measured in step 9, and automatically sets this in the molded product measurement memory 68. This product data tolerance value is calculated as a monitoring tolerance value based on the correlation graph in step 10, and this is automatically set in the tolerance value setter 70 in step 10.

As a result, the calculation unit 74 constantly monitors whether the execution data monitored during product molding in step 11 is within the range of the tolerance value modified in step 8 or the tolerance value modified in step 11 (step 11). 12)
, if it is outside the range, an abnormality is displayed from the alarm output circuit via the output circuit 48. Furthermore, if this data is within the allowable value, good product molding can be achieved in step 13.

In this way, it is possible to easily set the optimum conditions in the injection molding process for molding a good product.

[Effects of the Invention] As is clear from the above-mentioned embodiments, according to the method for setting the optimum monitor tolerance value for an injection molding machine of the present invention, there is a statistical correlation between the measured value of a non-defective molded product and the value of various non-defective product monitoring data. Determine the relationship, store this correlation in a storage medium, and display it as a graph on a display device,
By correcting the execution monitoring tolerance sampled during injection molding based on this correlation graph, the optimal monitoring tolerance value in the injection process can be easily set within a short time.

Furthermore, an arithmetic expression is determined from the correlation, and based on this arithmetic expression, a monitoring tolerance value is automatically set for the statistically determined acceptable value of a non-defective molded product, and this arithmetic expression and tolerance value are stored in a storage medium. Based on this correlation graph and tolerance values, the execution monitoring data values monitored during injection molding are displayed on the display device. Optimal monitor tolerance values can be set within a short time by simple operation.

In addition, according to the optimal monitor permissible Vi setting device for an injection molding machine, there are detection units installed at predetermined positions of the injection molding machine to detect the injection state in the injection molding process, and a detection unit that measures the injection molded product. Automatic needle 41! An IJ device, a drive control unit that controls each drive unit of the injection molding machine, and inputs the permissible values for execution monitoring sampled from the detection unit and sends command signals processed based on the permissible values to each of the drive control units. and a control device that outputs the non-defective molded product needle Wli measured by the automatic measuring device and the monitoring data value corresponding thereto, and a non-defective product data storage unit that stores the non-defective molded product needle Wli measured by the automatic measuring device and the monitoring data value corresponding thereto, and a function calculation unit that calculates an arithmetic expression from the statistical correlation of non-defective product monitoring data values, a display device that displays the correlation on a screen as a graph, and an allowable value of the measured value of the molded product measured based on the arithmetic expression. and an arithmetic unit that compares and calculates the monitoring tolerance value and the sampled execution monitoring tolerance value, and includes a non-defective molded product needle 8! ! A calculation formula can be obtained from the statistical correlation between the I value and the non-defective monitoring data value, and based on this calculation formula, the correlation graph can be easily manually corrected and set the monitor tolerance value monitored on the CRT screen. can do.

Furthermore, the control device includes a non-defective molded product measurement value measured by the automatic measuring device and a non-defective molded product measurement value and a corresponding monitoring data value sampled from each detection section; a function calculation section that calculates a calculation formula from statistical correlations of monitoring data values; a display device that displays the correlation and tolerance values on a screen as a graph; and a display device that calculates a calculation formula based on the calculation formula; A calculation unit that converts the value into a monitoring data tolerance value and compares the sampled execution monitoring tolerance value with this tolerance value, and a tolerance setting unit that automatically sets the monitoring tolerance value converted by this calculation unit. By configuring
゜The tolerance value of the measured value of the recorded molded product is converted into the tolerance value of the monitoring data value, and the sampled execution monitoring tolerance value is compared with this tolerance value, and the monitoring tolerance value converted by this calculation part is automatically calculated. By automatically correcting, setting, and monitoring the monitoring tolerance even if the molding conditions change over time, stable quality of the molded product can be obtained.

Although the preferred embodiments of the present invention have been described above, the method and apparatus for setting optimal conditions of the present invention are not limited to the above-described embodiments, and can also be applied to production machines other than injection molding round guttering. Of course, various design changes can be made without departing from the spirit of the invention.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, FIGS. 2 and 3 are correlation diagrams between molded product measurement values and monitoring data values showing one embodiment of the present invention, and FIG. is a flowchart. 10...Injection molding machine 14...Screw 18...Injection cylinder 22...Mold 26.28.30...Servo valve 32...Sensor 38...Pressure sensor 42...・Control device 44...CPU (central processing unit) 46...Input circuit 48...Output circuit 50・
...Alarm output circuit 52...Timer 54...Automatic measuring device 56...Keyboard (input device) 58...Display device (CRT) 60...CRT control circuit 62...Storage device 64... ... Good product data memory 12 ... Barrel 16 ... Bearing unit 20 ... Hydraulic motor 24 ... Mold clamping device 34, 36 ... Position sensor 40 ... Temperature sensor 66 ... Monitoring data memory 68... Molded product measurement memory 70... Tolerance value setter 72... Function calculator 74
. . . Arithmetic unit 76 . . . Address data bus FIG. FIG Drawing engraving (no change in content) Procedural amendment (method) % formula % 1. Indication of incident 1988 Patent Application No. 281362 2. Title of invention and the relationship with the device correction case Patent applicant address: 4-2-11, 4-chome, East Germany, name: (345) Toshiba Machine Co., Ltd. Akira Iwahashi

Claims (4)

[Claims] (1) Determine the tolerance value from the monitoring data values sampled by the control device during the molding process of the injection molding machine and the measured values of the molded product, correct the corresponding execution monitoring tolerance value, and perform injection molding. In a method for setting optimal monitor tolerance values for an injection molding machine, an arithmetic expression is determined from the statistical correlation between the measured values of the molded product and the various monitoring data values, and this arithmetic expression is stored in a storage medium and displayed on a display device. A method for setting an optimal monitoring tolerance value for an injection molding machine, which comprises displaying a graph, correcting the execution monitoring tolerance value during injection molding based on the correlation graph, and determining a non-defective product. (2) Injection molding in which tolerance values are determined from the monitoring data values sampled by the control device during the molding process of the injection molding machine and the measured values of the molded product, the corresponding monitoring tolerance values are corrected, and injection molding is performed. In the method for setting optimal monitor tolerance values for a molding machine, an arithmetic formula is determined from the statistical correlation between the measured values of the molded product and the various monitoring data values, and a tolerance value for a non-defective molded product is determined, and this arithmetic formula and the tolerance value are determined. The value is stored in a storage medium, the correlation is displayed as a graph on a display device together with the tolerance value, and the tolerance value of the monitoring data value is automatically set with respect to the acceptable measurement tolerance value of the molded product based on the calculation formula, and the injection molding is performed. 2. A method for setting an optimum monitoring tolerance value for an injection molding machine according to claim 1, wherein a non-defective product is determined by monitoring and correcting an execution monitoring tolerance value. (3) Determine the correlation between the measured values of the molded product molded by the injection molding machine and the monitoring data values sampled during injection molding, correct the execution monitoring tolerance based on this correlation, and determine the optimal monitoring tolerance. In an optimum monitor tolerance setting device for an injection molding machine that performs injection control by setting the An automatic measuring device that measures the product, a drive control unit that controls each drive unit of the injection molding machine, and an execution monitoring tolerance value sampled from the detection unit is input, and a command signal processed based on the tolerance value is input. a control device that outputs output to each of the drive control units; the control device includes a non-defective molded product measurement value measured by the automatic measuring device and a non-defective molded product measurement value and a monitoring data value corresponding to the non-defective product data storage unit; a function calculation section that calculates a calculation formula from a statistical correlation between the molded product measurement value and the non-defective product monitoring data value; a display device that displays the correlation on a screen as a graph; and a molded product that is measured based on the calculation formula. It is composed of a calculation unit that compares and calculates the measured value tolerance and monitoring tolerance value with the sampled execution monitoring tolerance value, and corrects the monitored execution monitoring tolerance value based on the graph displayed on the display device. An optimal monitor tolerance value setting device for an injection molding machine, characterized in that the optimal monitor tolerance value is set by (4) Determine the correlation between the measured values of the molded product molded by the injection molding machine and the monitoring data values sampled during injection molding, correct the execution monitoring tolerance based on this correlation, and determine the optimal monitoring tolerance. In an optimum monitor tolerance setting device for an injection molding machine that performs injection control by setting the An automatic measuring device that measures the product, a drive control unit that controls each drive unit of the injection molding machine, and an execution monitoring tolerance value sampled from the detection unit is input, and a command signal processed based on the tolerance value is input. and a control device that outputs to each of the drive control sections, the control device storing non-defective molded product measurement values measured by the automatic measurement device and monitoring data values sampled from each detection section corresponding to the non-defective product data. a storage unit, a function calculation unit that calculates an arithmetic expression from the statistical correlation between the measured values of the non-defective molded product and the non-defective monitoring data values, a display device that displays the correlation and the allowable value in a graph on a screen, and the calculation unit. an arithmetic unit that converts the acceptable value of the measured value of the non-defective molded product into an acceptable value of the monitoring data value based on a formula, and compares and calculates the sampled execution monitoring acceptable value with this acceptable value; and a tolerance value setting unit that automatically sets a monitoring tolerance value, and a tolerance value setting unit that automatically sets a monitoring tolerance value by correcting the monitored execution tolerance value based on the graph and tolerance value displayed on the display device. The optimum monitor tolerance value setting device for an injection molding machine according to claim 3.