JP2009160595A - Sensing apparatus, method for judging softening of forming mold, and method for judging filling condition of raw materials into forming mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for improving the non-defective product ratio of a formed product. <P>SOLUTION: A first judging means 90 inputs the total of strains and/or the difference of the strains, calculated with a first calculating means 72 at the same timing in the respective forming cycles and judges whether this value is in the softened judging range or not. In the case of judging that this value is in the softened judging range, a softened judging signal is inputted into a forming cycle controlling means 106. A second judging means 94 inputs the total of the strains calculated with a second calculating means 78 during forming cycle, and the total of the strains inputted after judging that this value is in a filling processing judging means, is judged whether this value is in the filling completion judging range or not. A third judging means 100 inputs the difference of the strains calculated with a third calculating means 84 and the total of the strains calculated with a third calculating means 84 during forming cycle, and the total of the strains inputted after judging that this value is in the filling processing judging range is judged whether this total is in the filling processing completion judging range or not. In the case of judging that this value is in the filling completion judging range, a filling completion judging signal is inputted in the forming cycle controlling means 106. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technique for softening a mold for molding a material and determining a filling state of the material into the mold.

Patent Document 1 discloses a technique for measuring pressure or frictional stress applied to the surface of a tool or a mold during plastic processing such as rolling, forging, extrusion, and drawing. The frictional stress here means a frictional force per unit area obtained by dividing the frictional force applied to the surface of the tool or mold by the surface area.
In the technique of Patent Document 1, a surface to be measured such as a tool or a mold is formed in a thin shape, a pair of beams extending from the back surface of the surface to be measured is provided, and the tips of the pair of beams are connected with a thin plate, A pair of strain sensors for measuring strain generated in the thin plate is provided. The pair of strain sensors are respectively provided at portions connected to the pair of beams on the thin plate. A strain sensor is provided, and the strain generated in the thin plate is measured by each strain sensor. According to the technique of Patent Document 1, the pressure and frictional stress applied to the surface to be measured can be calculated from the strain measured by the pair of strain sensors. For example, the pressure applied to the surface to be measured can be calculated by calculating the sum of the strains measured by the pair of strain sensors. Alternatively, the frictional stress applied to the surface to be measured can be calculated by calculating the difference between the strains measured by the pair of strain sensors. According to the technique of Patent Document 1, it is possible to simultaneously measure the pressure and frictional stress applied to the surface to be measured.

JP 2004-77140 A

The technique of Patent Document 1 can be used favorably as a means for measuring pressure and frictional force applied to the surface of a molding die of a molding apparatus.
The present invention provides a technique for determining the softening of a mold or the filling state of a material into the mold and improving the yield rate in a molding apparatus using the technique of Patent Document 1.

The present invention can be embodied in a sensing device. This apparatus includes a first thin-walled portion provided on a part of a molding surface of a mold for molding the material in contact with the material, and a first beam extending in parallel with each other from an anti-molding surface of the first thin-walled portion. A first connection part extending between the pair of parts, a first beam part pair, a first strain sensor for measuring strain generated in the first connection part on one side of the first beam part pair, and a first connection part A second strain sensor for measuring the strain generated in the first beam portion pair on the other side, a first strain sum calculating means for calculating a sum of strains measured by the first strain sensor and the second strain sensor, A first strain difference calculating means for calculating a difference between strains measured by the strain sensor and the second strain sensor; a strain sum calculated by the first strain sum calculating means; and / or a strain calculated by the first strain difference calculating means. The mold softening judgment range related to the difference between the molds is memorized, and each molding cycle is performed for each molding cycle or cycles. The strain sum calculated by the first strain sum calculating means and / or the strain difference calculated by the first strain difference calculating means are input at the same timing, and the inputted strain sum and / or strain difference is stored. First determining means for determining whether or not the softening determination range is within the range.
The first thin portion is preferably formed at a location that is easily affected by softening on the molding surface, but the installation location is not particularly limited. For example, you may provide a 1st thin part in a part with a long time which contacts a high temperature raw material at the time of the shaping | molding process on a shaping | molding surface.

In the sensing device having the above-described structure, the first thin portion is distorted according to the force and heat applied to the molding surface by the material filled in the mold, and is connected to the first thin portion via the first beam portion pair. Distortion also occurs in the first connecting portion. The strain generated in the first connecting portion is measured by the first strain sensor and the second strain sensor. A 1st strain sensor measures the distortion which arose in the 1st connection part in the part by the side connected to one side of the 1st beam part pair of a 1st connection part. A 2nd strain sensor measures the distortion which arose in the 1st connection part in the part by the side connected to the other of the 1st beam part pair of a 1st connection part.
The strain measured by the first strain sensor and the second strain sensor is input to the first strain sum calculation means and the first strain difference calculation means, and the sum of the strains measured by both sensors and the difference between the strains are calculated. . The calculated strain sum corresponds to the pressure applied to the first thin portion, and the calculated strain difference corresponds to the frictional stress applied to the first thin portion.

  A molding cycle in which a material is molded into a molded product by a molding die is repeatedly performed, and a large number of molded products are molded. In the present specification, a series of processing processes from when a material is placed in a mold and molding is started until the next material is placed in the mold is referred to as a molding cycle. That is, one molded product is molded by one molding cycle, and a plurality of molded products are molded by repeatedly executing a plurality of molding cycles.

As the above molding cycle is repeated, the mold may soften. Softening refers to a phenomenon in which the material forming the mold is annealed by the pressure and heat applied to the mold in a plurality of molding cycles, and the hardness of the mold decreases. When softening occurs in the mold, residual strain occurs in the mold. When softening occurs in the mold, the residual strain generated in the mold increases as the molding cycle is repeated.
When a molding cycle is performed using a mold that has been softened and has been permanently deformed (abrasion / deformation), there arises a problem that the defective product rate of the molded product is significantly increased.

When residual strain occurs in the mold, the amount of strain measured by the first strain sensor and the second strain sensor increases. Further, even when no force is applied to the mold, the strain is measured by the first strain sensor and the second strain sensor. Therefore, it is possible to determine whether or not softening has occurred in the mold by monitoring the sum of strains or the difference in strains measured by the first strain sensor and the second strain sensor.
In the sensing device according to the present invention, the first determination means determines whether or not the mold is softened. The first determination means inputs the sum of strains calculated by the first strain sum calculation means and / or the strain difference calculated by the first strain difference calculation means for each molding cycle or a plurality of molding cycles. The input strain sum and / or strain difference is calculated at the same timing in each molding cycle. The timing for calculating the sum of strains and / or the difference in strains may be, for example, at the start of the molding cycle or at the middle of the molding cycle. That is, it may be a period during which the material is not subjected to molding or a period during which the material is subjected to molding. Further, when the temperature change is large as in hot forging, in order to subtract the temperature drift amount of the strain sensor, the temperature of the sensing device may be measured so that the net strain can be measured.

  The first determination means stores a softening determination range of the mold relating to the above-described sum of strains and / or strain differences. Then, by determining whether the sum of input strains and / or the difference in strain is within the softening determination range, it is possible to accurately determine whether softening occurs in the mold. The softening determination range is obtained in advance by, for example, experiments or numerical calculations, and varies depending on the material and structure of the mold. The softening determination range can be determined only by the upper limit value, for example. In this case, it can be determined that softening has occurred in the mold when the sum of strains and / or the strain difference exceeds the upper limit.

The first determination means stores only the mold softening determination range related to the sum of strains, inputs only the calculated sum of strains, and performs softening determination of the mold based only on the sum of strains. it can. Alternatively, the first determination means stores only the mold softening determination range relating to the strain difference, inputs only the calculated strain difference, and performs the mold softening determination based only on the strain difference. You can also Further, the first determination means stores a mold softening determination range for each of the strain sum and the strain difference, inputs both the calculated strain sum and the strain difference, and inputs the strain sum. It is also possible to make a softening judgment based on the difference between the softening judgment based on the difference and the difference in strain. Whether to determine softening using the sum of strains or the difference between strains can be selected as appropriate according to the portion where the first thin portion is provided on the molding surface. For example, if the first thin portion is provided at a location where the material flows in parallel, shear deformation occurs in the first thin portion. That is, residual strain is generated in the mold due to shear deformation of the mold. In such a case, it is preferable that the first determining means determine softening using a difference in strain.
According to the sensing device of the present invention, it is possible to detect that the mold has been softened, and it is possible to prevent the molding cycle from being repeated using the mold that has been deformed by the softening. Thereby, the non-defective product rate of the molded product can be improved.

As described above, the softening determination range for determining the softening of the mold can be obtained in advance by, for example, experiments or numerical calculations. However, at the time of actual molding, the pressure and temperature conditions applied to the mold may be different from the planned values, and in this case, the softening determination range may need to be corrected. For this reason, in the sensing device described above, the first determination means may correct the stored softening determination range using the sum of input strains and / or the difference in strains. As a result, the softening determination range can be corrected in consideration of the pressure and temperature conditions during actual molding.
Further, as described above, when softening occurs in the mold, the hardness of the mold significantly decreases. For this reason, before and after the occurrence of softening, the sum of strains input to the first determination means and the difference between the strains change rapidly. Therefore, it is possible to determine that softening has occurred in the mold by monitoring the increment between the sum or strain difference input earlier and the sum or strain difference input immediately thereafter. Become. Therefore, in the sensing device according to the present invention, the first determination unit may update the stored softening determination range each time a strain sum and / or a strain difference is input. That is, the softening determination range used in the next molding cycle can be set based on the sum of strains and / or the strain difference input in the current molding cycle. Thereby, the softening determination of the mold can be performed based on the sum of the strains between the molding cycles and / or the increment of the strain difference.

In the above sensing device, it is preferable that a thin second thin portion is provided in a portion of the molding surface of the molding die where the material flows substantially vertically during molding. In this case, the second beam portion pair extending in parallel with each other from the anti-molding surface of the second thin portion, the second connection portion extending between the second beam portion pair, and the distortion generated in the second connection portion. A third strain sensor for measuring one side of the second beam portion pair, a fourth strain sensor for measuring strain generated in the second connecting portion on the other side of the second beam portion pair, a third strain sensor, and a fourth strain; A second strain sum calculating means for calculating the sum of strains measured by the sensor, and a filling progress judgment range and a filling completion judgment range due to material flow of the material relating to the sum of strains calculated by the second strain sum computing means; And after inputting the sum of strains calculated by the second strain sum calculation means during the molding cycle by the mold over time, and determining that the input sum of strains is within the stored filling progress determination range, A second determination means for determining whether or not the sum of the input strains is within a filling completion determination range; Preferred.
Here, the above-described filling progress determination range indicates a range when the second connecting portion bends away from the second thin portion, and the above-described filling completion determination range indicates that the second connecting portion has the second thin portion. It is preferable to show the range when it bends to the side which approaches.

In the molding surface, the part where the material flows perpendicularly to the molding surface at the time of molding is, for example, a part located at the end of the molding surface and a part where the material is finally filled. The second thin-walled portion provided in such a portion starts to deform before the material actually contacts by the heat and pressure applied to the other portion of the molding surface. It should be noted that the deformation direction of the second thin portion at this time is opposite to the deformation direction after the material contacts the second thin portion.
When the second thin portion is deformed as described above, the second connecting portion connected to the second thin portion via the second beam portion pair is also deformed. Specifically, until the material comes into contact with the second thin portion, as the material approaches the second thin portion, the second thin portion and the second connecting portion are deformed to be separated from each other. This is because the second connecting portion bends in a convex shape in the direction opposite to the direction in which the second thin portion is provided, and the second thin portion in the direction opposite to the direction in which the second connecting portion is provided. In other words, it can bend into a convex shape. After the material contacts the second thin portion, the second thin portion and the second connecting portion are deformed to approach each other according to the pressure applied to the second thin portion by the material. From this, it is possible to detect that the material has approached the second thin portion by detecting that the second connecting portion is deformed to the side away from the second thin portion. After that, the second connecting portion is deformed to the side approaching the second thin portion. In other words, the second connecting portion is bent in a convex shape in the direction in which the second thin portion is provided, and the second thin portion is bent in a convex shape in the direction in which the second connecting portion is provided. You can also. By detecting that the second connecting portion has undergone such deformation, it is possible to detect that the material has approached the second thin portion.

In the above sensing device, the strain generated in the second thin portion during the molding cycle is measured by the third strain sensor and the fourth strain sensor, and the sum of the strains measured by both sensors is input to the second determination means. The The second determination means includes a filling progress determination range indicating a range when the second connecting portion bends away from the second thin portion with respect to the sum of input strains, and the second connecting portion is set to the second thin portion. The filling completion determination range indicating the range when bending toward the approaching side is stored. Then, after determining that the sum of the input strains is within the stored filling progress determination range, the second determination means determines whether or not the input sum of strains is within the filling completion determination range. That is, it is determined that the material has contacted the second thin portion after detecting that the material has approached the second thin portion. Therefore, even when the filling completion determination range is set to a range corresponding to a slight pressure as compared with the method of simply detecting the pressure applied to the second thin portion by the material, it is caused by noise from the outside. An erroneous determination can be prevented. If the filling completion judgment range can be set to a range corresponding to a slight pressure, the completion of filling of the material can be detected at an appropriate timing, and an excessive molding load is prevented from being applied unnecessarily to the mold. be able to.
By using this sensing device, it is possible to satisfactorily prevent the molded product from being thin. Furthermore, the molding load by the molding die can be kept to the minimum necessary load. It is possible to reduce the burden on the mold and improve the yield rate of molded products.

  In the above-described sensing device, it is preferable that a thin third thin portion is provided in a portion of the molding surface of the molding die where the material flows substantially in parallel. In this case, the third beam portion pair extending in parallel with each other from the anti-molding surface of the third thin portion, the third connection portion extending between the third beam portion pair, and the distortion generated in the third connection portion. A fifth strain sensor for measuring one side of the third beam portion pair, a sixth strain sensor for measuring strain generated in the third connecting portion on the other side of the third beam portion pair, a fifth strain sensor, and a sixth A third strain sum calculating means for calculating a sum of strains measured by the strain sensor; a third strain difference calculating means for calculating a difference between strains measured by the fifth strain sensor and the sixth strain sensor; The filling completion determination range by the material flow of the material related to the sum of the strains calculated by the sum calculation means and the filling progress determination range by the material flow of the materials related to the strain difference calculated by the third strain difference calculation means are stored. The strain sum calculated by the third strain sum calculation means and the third strain difference calculation means calculated during the molding cycle by The difference between the input strains is input over time, and after determining that the input strain difference is within the memorized filling progress judgment range, is the sum of the input strains within the memorized filling completion judgment range? It is preferable to further include third determination means for determining whether or not.

In the molding surface, the part where the material flows parallel to the molding surface during molding is, for example, a part located in the middle of the molding surface, which is a part where the material flows during molding of the material. The third thin part provided in such a part is deformed by receiving frictional force from the material while the material is flowing, and deformed by receiving pressure from the material after the flow of the material is stopped after molding is completed. To do.
As the third thin portion is deformed as described above, the third connecting portion connected to the third thin portion via the third beam portion pair is also deformed. The strain generated in the third connecting portion is measured by the fifth strain sensor and the sixth strain sensor. While the material is flowing, the third connecting portion mainly receives frictional force from the material, so that a significant difference occurs in the strain measured by the fifth strain sensor and the sixth strain sensor. After the flow of the material stops after the molding is completed, the third connecting portion receives pressure mainly from the material, so that the sum of strains measured by the fifth strain sensor and the sixth strain sensor is significantly increased. Therefore, by monitoring the difference in strain measured by the fifth strain sensor and the sixth strain sensor, it can be detected that the material flows through the third thin portion. Then, by monitoring the sum of strains measured by the fifth strain sensor and the sixth strain sensor, it is possible to detect that the flow has stopped and the molding has been completed.

  In the above sensing device, the difference between the sum of the strains measured by the fifth strain sensor and the sixth strain sensor and the strain measured by the fifth strain sensor and the sixth strain sensor during the molding cycle is determined by the third determination. Input to the means. The third determination means stores a filling progress determination range related to the difference in input strain and a filling completion determination range related to the sum of input strains. Then, after determining that the difference between the input strains is in the stored filling progress determination range, the third determination means determines whether or not the sum of the input strains is in the stored filling completion determination range. judge. That is, after detecting that the material is flowing in the third thin portion, it is determined that the flow of the material is stopped and the molding is completed. Therefore, even when the filling completion determination range is set to a range corresponding to a slight pressure, compared to a method of simply detecting the pressure applied by the material to the third thin portion, erroneous determination caused by external noise Can be prevented. If the filling completion judgment range can be set to a range corresponding to a slight pressure, the completion of filling of the material can be detected at an appropriate timing, and an excessive molding load is prevented from being applied unnecessarily to the mold. be able to. It is possible to prevent an excessive load from being applied to the mold.

In the above sensing device, each thin portion may be individually provided on the molding surface, and one thin portion serves as one of the first thin portion, the second thin portion, and the third thin portion. May be. For example, the first thin portion, the first beam portion pair, the first connecting portion, the first strain sensor, the second strain sensor, the second thin portion, the second beam portion pair, and the second connecting portion. In addition, the third strain sensor and the fourth strain sensor may be used together. The first distortion sum calculation means may also serve as the second distortion sum calculation means. In this case, the first determination means inputs the sum of the strains calculated by the first strain sum calculation means and / or the strain difference calculated by the first strain difference calculation means, and executes the softening determination of the mold. The second determination means inputs the sum of the strains calculated by the second strain sum calculation means that is also used as the first strain sum calculation means, and executes the material filling state determination.
According to said sensing apparatus, it can prevent favorably that a missing part arises in a molded article. Furthermore, the molding load by the molding die can be kept to the minimum necessary load. It is possible to reduce the burden on the mold and improve the yield rate of molded products.

According to the present invention, the following sensing device can also be realized. This sensing device is a part of a molding surface of a molding die for forming a material in contact with the material, and a thin second thin portion provided in a portion where the material flows substantially vertically during molding, and a second thin wall A second beam portion pair extending in parallel with each other from the anti-molding surface of the portion, a second connecting portion extending between the second beam portion pair, and a strain generated in the second connecting portion. A third strain sensor to be measured on one side, a fourth strain sensor to measure the strain generated in the second connecting portion on the other side of the second beam pair, and a strain measured by the third strain sensor and the fourth strain sensor. 2nd strain sum calculation means for calculating the sum of the values, and a filling progress judgment range and a filling completion judgment range by the material flow of the material related to the sum of the strains calculated by the second strain sum calculation means are stored, and molding by the mold The sum of strains calculated by the second strain sum calculation means during the cycle is input over time, and the input sum of strains is recorded. Since it is determined that the filling progresses determination range being the sum of the input distortion and a second determination means for determining whether or not there in complete determination range filling. Here, the above-described filling progress determination range indicates a range when the second connecting portion bends away from the second thin portion, and the filling progress determination range indicates that the second connecting portion approaches the second thin portion. The range when it bends to the side to do is shown.
According to this sensing device, it is possible to satisfactorily prevent the occurrence of lacking in the molded product. Furthermore, the molding load by the molding die can be kept to the minimum necessary load. It is possible to reduce the burden on the mold and improve the yield rate of molded products.

According to the present invention, still another sensing device can be realized. This sensing device is a part of a molding surface of a molding die that molds a material in contact with the material, and a thin third thin portion provided in a portion where the material flows substantially in parallel during molding, The third beam portion pair extending in parallel with each other from the opposite side of the thin-walled portion, the third connection portion extending between the third beam portion pair, and the distortion generated in the third connection portion A fifth strain sensor that is measured on one side, a sixth strain sensor that measures the strain generated in the third connecting portion on the other side of the third beam pair, and a fifth strain sensor and a sixth strain sensor. The third strain sum calculating means for calculating the sum of the strains, the third strain difference calculating means for calculating the difference between the strains measured by the fifth strain sensor and the sixth strain sensor, and the third strain sum calculating means. Material related to the difference in strain calculated by the third strain difference calculating means and the filling completion judgment range due to material flow of the material related to the sum of strains The filling progress judgment range due to material flow is stored, and the sum of strains calculated by the third strain sum calculation means and the strain difference calculated by the third strain difference calculation means during the molding cycle by the mold are input over time. And determining whether the sum of the input strains is within the stored filling completion determination range after determining that the difference between the input strains is within the stored filling progress determination range. It has.
According to this sensing device, it is possible to satisfactorily prevent the occurrence of lacking in the molded product. Furthermore, the molding load by the molding die can be kept to the minimum necessary load. It is possible to reduce the burden on the mold and improve the yield rate of molded products.

According to the present invention, a novel and useful method for determining softening of a mold can be provided. In this method, a first thin-walled portion provided on a part of a molding surface of a mold for molding the material in contact with the material, and a first beam extending in parallel with each other from an anti-molding surface of the first thin-walled portion A first connection part extending between the pair of parts, a first beam part pair, a first strain sensor for measuring strain generated in the first connection part on one side of the first beam part pair, and a first connection part The softening of the mold is determined using a sensing device including a second strain sensor that measures the strain generated in the second beam portion on the other side of the first beam portion pair. This method includes a first strain sum calculation step of calculating a sum of strains measured by the first strain sensor and the second strain sensor at the same timing in each molding cycle for every one or a plurality of molding cycles by the mold. And a first strain difference calculation step of calculating a difference between strains measured by the first strain sensor and the second strain sensor at the same timing in each molding cycle for every one or a plurality of molding cycles by the mold. A first determination step for determining whether the sum of the strains calculated in the first strain sum calculation step and / or the difference in strains calculated in the first strain difference calculation step are within a preset softening determination range. Is provided.
According to this method, it is possible to detect the occurrence of softening in the mold, and it is possible to prevent the molding cycle from being repeated using the mold that is deformed by the softening. Thereby, the non-defective product rate of the molded product can be improved.

According to the present invention, a second thin-walled portion that is part of a molding surface of a molding die that molds the material in contact with the material and that is provided in a portion where the material flows substantially vertically during molding, The second beam portion pair extending in parallel with each other from the opposite side of the thin-walled portion, the second connecting portion extending between the second beam portion pair, and the distortion generated in the second connecting portion The material of the raw material to the mold using a sensing device comprising a third strain sensor for measuring one side of the second strain sensor and a fourth strain sensor for measuring the strain generated in the second connecting portion on the other side of the second beam portion pair A method for determining a filling state by flow can be realized. This method is calculated in the second strain calculation step and the second strain calculation step in which the sum of strains measured by the third strain sensor and the fourth strain sensor is calculated over time during the molding cycle by the mold. After determining that the sum of the strains is within the filling progress determination range due to the material flow of the material set in advance, the second determination is made as to whether or not the sum is within the filling completion determination range due to the material flow of the material set in advance. A determination step is provided. Here, the filling progress determination range indicates a range when the second connecting portion bends away from the second thin portion, and the filling completion determination range indicates a side where the second connecting portion approaches the second thin portion. The range when it bends is shown.
According to this method, it is possible to satisfactorily prevent the occurrence of lacking in the molded product. Furthermore, the molding load by the molding die can be kept to the minimum necessary load. It is possible to reduce the burden on the mold and improve the yield rate of molded products.

According to the present invention, a third thin-walled portion that is a part of a molding surface of a mold that molds the material in contact with the material and that is provided in a portion where the material flows substantially parallel during molding, and the third thin-walled portion A third beam portion pair extending in parallel with each other from the anti-molding surface of the portion, a third connecting portion extending between the third beam portion pair, and a distortion generated in the third connecting portion. Using a sensing device that includes a fifth strain sensor that measures on one side and a sixth strain sensor that measures the strain generated in the third connecting portion on the other side of the third beam pair, the material filling state in the mold Other methods of determining can also be implemented. This method includes a third strain sum calculating step of calculating a sum of strains measured by the fifth strain sensor and the sixth strain sensor over time during a molding cycle by the mold, and a molding cycle by the mold. The third strain difference calculation step for calculating the strain difference measured by the fifth strain sensor and the sixth strain sensor over time, and the strain difference calculated in the third strain difference calculation step is a preset material. After determining that it is in the filling progress determination range due to material flow, it is determined whether or not the sum of strains calculated in the third strain sum calculation step is within a predetermined range for filling completion due to material flow of the material. A third determination step is provided.
According to this method, it is possible to satisfactorily prevent the occurrence of lacking in the molded product. Furthermore, the molding load by the molding die can be kept to the minimum necessary load. It is possible to reduce the burden on the mold and improve the yield rate of molded products.

  According to the present invention, it is possible to accurately determine the softening of the mold or the filling state of the raw material into the mold, and efficiently prevent the occurrence of defects in the molded product. Thereby, the non-defective product rate of the molded product can be improved.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a molding apparatus 2 according to an embodiment of the present invention. The molding apparatus 2 includes an upper mold 10 and a lower mold 12. The lower mold 12 includes recesses 12 a, 12 b, and 12 c and is fixed to the lower support base 14. The shaft 4 and the shaft 16 are fixed to the respective ends of the lower support base 14. The upper mold 10 includes a recess 10 a and is fixed to the upper support base 8. A cylinder 6 and a cylinder 18 are provided at each end of the upper support base 8. The cylinders 6 and 18 can slide along the shafts 4 and 16, respectively, and can move the upper mold 10 in the vertical direction. The molding apparatus 2 disposes a material (not shown) between the upper mold 10 and the lower mold 12, moves the upper mold 10 downward, and moves the material between the upper and lower molds 10, 12. A molded product is formed by filling 10a, 12a, 12b, and 12c.

The molding device 2 further includes a control device 20. The control device 20 includes a monitor 22 and input means 24. The control device 20 controls the molding process of the molding device 2. The monitor 22 displays the progress of the molding process, the presence / absence of an abnormality such as the occurrence of softening, and the filling state of the material. The input unit 24 includes an input unit such as a keyboard and buttons. The processing system of the molding process of the control device 20 will be described in detail later.
The lower mold 12 also includes measuring devices 26, 43, and 57. The measuring device 26 is provided on the side opposite to the molding surface 12d of the molding surface 12d of the lower mold 12. The measuring device 43 is provided on the side opposite to the molding surface of the bottom surface 12e of the recess 12c. The measuring device 57 is provided on the side opposite to the molding surface of the side surface 12f of the recess 12c. The measuring devices 26, 43, and 57 can be provided at predetermined positions of the lower mold 12 by a technique such as press fitting or shrink fitting. The measuring devices 26, 43, and 57 may be integrally formed with the lower mold 12.
In this embodiment, the presence or absence of softening of the lower mold 12 is determined by the strain measured by the measuring device 26. Further, the filling state of the material into the lower mold 12 is determined by the strain measured by the measuring device 43 and the strain measured by the measuring device 57. The measured strain outputs data by wire or wirelessly through the opening 111 for measuring device data output.

FIG. 2 is a partial cross-sectional view of the molding apparatus 2 on the molding surface 12d. The measuring device 26 is a device that measures the force applied to the molding surface 12d of the lower mold 12. A first thin portion 29 is formed on a part of the molding surface 12d. That is, in the lower mold 12, the first thin portion 29 is formed thinner than the surrounding portion. A cavity 32 is formed on the back surface 28 side (reverse molding surface side) of the first thin portion 29, and a measuring device 26 is provided therein.
The measuring device 26 includes a first beam pair 34, 42, a first connecting plate 38, a first strain sensor 36, and a second strain sensor 40. The first beam portion pair 34, 42 extends in parallel from the back surface 28 side of the first thin portion 29. The first beam portion 34 and the first beam portion 42 have the same plate shape. The first beam portion pairs 34 and 42 are individually manufactured and then fixed to the first thin portion 29. Note that the first beam portion pair 34, 42 can also be formed integrally with the first thin portion 29.
The first connecting plate 38 extends between the first beam portion pair 34 and 42 and is connected to the distal end portion of the first beam portion pair 34 and 42. The first connecting plate 38 has a plate shape.

  A first strain sensor 36 and a second strain sensor 40 are provided on the lower surface (the lower surface in FIG. 2) of the first connecting plate 38. The first strain sensor 36 is provided at a connection portion where the first beam portion 34 is connected to the first connecting plate 38. The second strain sensor 40 is provided at a connection portion where the first beam portion 42 is connected to the first connecting plate 38. The first strain sensor 36 and the second strain sensor 40 are arranged in the direction in which the first beam portion pair 34 and 42 are opposed to each other, and measure the strain generated in the first connecting plate 38 in the above direction.

FIG. 3 is a partial cross-sectional view of the molding device 2 in the recess 12c. The measuring device 43 is a device that measures the force applied to the bottom surface 12 e of the recess 12 c of the lower mold 12. A second thin portion 44 is formed on a part of the bottom surface 12e. That is, in the lower mold 12, the second thin portion 44 is formed thinner than the surrounding portion. A cavity 46 is formed on the back surface 45 side (reverse molding surface side) of the second thin portion 44, and a measuring device 43 is provided therein.
The measuring device 43 includes a second pair of beam portions 48 and 56, a second connecting plate 52, a third strain sensor 50, and a fourth strain sensor 54. The second beam portion pairs 48 and 56 extend in parallel with each other from the back surface 45 side of the second thin portion 44. The second beam portion 48 and the second beam portion 56 have the same plate shape. The second beam portion pairs 48 and 56 are individually manufactured and then fixed to the second thin portion 44. Note that the second beam portion pair 48, 56 can also be formed integrally with the second thin portion 44.
The second connecting plate 52 extends between the second beam portion pair 48 and 56 and is connected to the distal end portion of the second beam portion pair 48 and 56. The second connecting plate 52 has a plate shape.

  A third strain sensor 50 and a fourth strain sensor 54 are provided on the lower surface (the lower surface in FIG. 3) of the second connecting plate 52. The third strain sensor 50 is provided at a connection portion where the second beam portion 48 is connected to the second connecting plate 52. The fourth strain sensor 54 is provided at a connection portion where the second beam portion 56 is connected to the second connecting plate 52. The third strain sensor 50 and the fourth strain sensor 54 are arranged in a direction in which the second beam pair 48 and 56 are opposed to each other, and measure the strain generated in the second connecting plate 52 in the above direction.

The measuring device 57 is a device that measures the force applied to the side surface 12 f of the recess 12 c of the lower mold 12. A third thin portion 58 is formed on a part of the side surface 12f. That is, in the lower mold 12, the third thin portion 58 is formed thinner than the surrounding portion. A cavity 60 is formed on the back surface 59 side (reverse molding surface side) of the third thin portion 58, and a measuring device 57 is provided therein.
The measuring device 57 includes a third beam portion pair 62, 70, a third connecting plate 66, a fifth strain sensor 64, and a sixth strain sensor 68. The third beam portion pairs 62 and 70 extend in parallel from the back surface 59 side of the third thin portion 58. The third beam portion 62 and the third beam portion 70 have the same plate shape. The third beam portion pairs 62 and 70 are individually manufactured and then fixed to the third thin portion 58. Note that the third beam portion pairs 62 and 70 may be formed integrally with the third thin portion 58.
The third connecting plate 66 extends between the third beam portion pair 62 and 70 and is connected to the distal end portion of the third beam portion pair 62 and 70. The third connecting plate 66 has a plate shape.

  A fifth strain sensor 64 and a sixth strain sensor 68 are provided on the lower surface of the third connecting plate 66 (the right surface in FIG. 2). The fifth strain sensor 64 is provided at a connection portion where the third beam portion 62 is connected to the third connecting plate 66. The sixth strain sensor 68 is provided at a connection portion where the third beam portion 70 is connected to the third coupling plate 66. The fifth strain sensor 64 and the sixth strain sensor 68 are arranged in a direction in which the third beam pair 62 and 70 are opposed to each other, and measure the amount of strain generated in the third connecting plate 66 in the above direction.

  In the molding apparatus 2 described above, the first beam portion pair 34, 42, the second beam portion pair 48, 56, the third beam portion pair 62, 70, the first connecting plate 38, the second connecting plate 52, The third connecting plate 66 can be formed of the same material as the lower mold 12 or can be formed of a different material. In this embodiment, the first beam portion pair 34, 42, the second beam portion pair 48, 56, the third beam portion pair 62, 70, the first connecting plate 38, the second connecting plate 52, The three connecting plates 66 are made of the same material as the lower mold 12. If each beam portion pair and each connecting plate are formed of the same material as the lower mold 12, the force and heat applied to the first thin portion 29, the second thin portion 44, and the third thin portion 58 are used. The impact can be measured more accurately.

  FIG. 4 is a block diagram illustrating a configuration of an electrical processing system of the molding apparatus 2. As shown in FIG. 4, the molding apparatus 2 includes a first calculation unit 72 connected to the first strain sensor 36 and the second strain sensor 40, and a first strain sensor 50 connected to the third strain sensor 50 and the fourth strain sensor 54. 2 calculation means 78, third calculation means 84 connected to the fifth strain sensor 64 and sixth strain sensor 68, first determination means 90 connected to the first calculation means 72, and second calculation means 78 Molding cycle control connected to the second determination means 94 connected, the third determination means 100 connected to the third calculation means 84, the first determination means 90, the second determination means 94, and the third determination means 100. Means 106, input means 24, and monitor 22 are provided.

Molding processing by the molds 10 and 12 is controlled by the molding cycle control means 106. The molding processing by the molds 10 and 12 is performed on the lower mold 12 by pressing the upper mold 10 by processing the material in the spaces 10a, 12a, 12b and 12c between the molds 10 and 12. It includes a process of pressurizing the placed material, a process of solidifying the material in a pressurized state, a step of taking out the molded product after solidification from the molds 10 and 12, and the like. In the present embodiment, the above-described series of molding processing is referred to as a molding cycle. In the molding apparatus 2, a molded product is molded by repeating the molding cycle described above.
The monitor 22 displays the progress status of the molding cycle executed under the control of the molding cycle control means 106. Instructions from the operator, such as start and stop of the molding cycle, are input by the input means 24, and the molding process control device 106 executes the molding cycle according to the input instructions.

  The calculation processes of the first calculation means 72, the second calculation means 78, and the third calculation means 84 are substantially the same. Therefore, hereinafter, the calculation process of the first calculation means 72 will be described in detail, and an effort will be made to avoid overlapping description of the second calculation means 78 and the third calculation means 84.

  The first calculation means 72 includes first distortion sum calculation means 74 and first distortion difference calculation means 76. The first strain sum calculation means 74 calculates the sum of strains measured by the first strain sensor 36 and the second strain sensor 40. On the other hand, the first strain difference calculation means 76 calculates the difference in strain measured by each of the first strain sensor 36 and the second strain sensor 40. As will be described below, the sum of strains changes according to the force and heat applied perpendicularly to the molding surface 12 d in the first thin portion 29. Further, the difference in strain changes according to the force and heat applied in parallel to the molding surface 12 d in the first thin portion 29.

  When pressure is applied to the first thin portion 29 from the vertical direction, the first thin portion 29 bends downward. At this time, the first beam portion pairs 34 and 42 tend to tilt in opposite directions so that the tip portions thereof are separated from each other. As a result, the first connecting plate 38 is deformed in a mirror-symmetrical manner (even function) with reference to an intermediate position between the first beam portion pair 34 and 42. Further, when a negative pressure is applied to the first thin portion 29 or when heat is applied from the vertical direction, the first thin portion 29 bends upward. At this time, the first beam portion pairs 34 and 42 tend to tilt in opposite directions so that their tip portions approach each other. Even in this case, the first connecting plate 38 is deformed mirror-symmetrically (evenly functioning) with respect to the intermediate position of the first beam pair 34, 42 as a reference. As described above, the first connecting plate 38 is mirror-symmetrically (evenly functioning) deformed with respect to the force and heat applied to the first thin portion 29. Accordingly, each of the first beam portion pairs 34 and 42 outputs substantially the same amount of strain with respect to the pressure applied to the first thin portion 29.

On the other hand, when a force or heat from a parallel direction is applied to the first thin portion 29, the first thin portion 29 bends downward on the upper side in the direction in which the force or heat is applied, and first on the lower side. The thin portion 29 bends upward. At this time, the first beam portion pair 34, 42 tends to tilt in the same direction. As a result, the first connecting plate 38 is deformed point-symmetrically (odd function) with the intermediate position of the first beam portion pair 34, 42 as a reference. Therefore, for the force and heat applied in parallel to the first thin portion 29, the first strain sensor 36 and the second strain sensor 40 output strain amounts having the same magnitude and opposite signs (positive / negative). To do.
From the above, the sum (or average value) of the strains measured by the first strain sensor 36 and the second strain sensor 40 cancels out the strain caused by the force applied in the direction parallel to the first thin portion 29. Thus, the distortion caused by the force applied in the vertical direction to the first thin portion 29 is correctly shown. In addition, the difference in strain measured by the first strain sensor 36 and the second strain sensor 40 cancels out the strain caused by the force applied in the direction perpendicular to the first thin portion, and the first thin portion 29 On the other hand, the distortion due to the force applied in the parallel direction is correctly shown.

  The second calculation means 78 includes a second distortion sum calculation means 80 and a second distortion difference calculation means 82. The second strain sum calculation means 80 calculates the sum of the strain amounts measured by the third strain sensor 50 and the fourth strain sensor 54. On the other hand, the second strain difference calculation means 76 calculates the difference between the strain amounts measured by the third strain sensor 50 and the fourth strain sensor 54. The sum of the strains measured by the third strain sensor 50 and the fourth strain sensor 54 changes according to the force and heat applied perpendicularly to the second thin portion 44. The difference in strain measured by the third strain sensor 50 and the fourth strain sensor 54 changes according to the force and heat applied in parallel to the second thin portion 44. The calculation process executed by the second calculation unit 78 is substantially the same as that of the first calculation unit 72.

  The third calculation means 84 includes third distortion sum calculation means 86 and third distortion difference calculation means 88. The third strain sum calculation means 86 calculates the sum of the strains measured by the fifth strain sensor 64 and the sixth strain sensor 68, respectively. On the other hand, the third strain difference calculation means 76 calculates the difference in strain measured by each of the fifth strain sensor 64 and the sixth strain sensor 68. The sum of strains measured by the fifth strain sensor 64 and the sixth strain sensor 68 changes according to the force and heat applied perpendicularly to the third thin portion 58. Further, the difference in strain measured by the fifth strain sensor 64 and the sixth strain sensor 68 changes according to the force and heat applied in parallel to the third thin portion 58. The calculation process executed by the third calculation unit 84 is substantially the same as that of the first calculation unit 72.

The first determination unit 90 includes a softening determination range storage unit 92 that stores a softening determination range related to the sum of strains calculated by the first strain sum calculation unit 74. The first determination means 90 has, in each molding cycle, the sum of strains calculated by the first calculation means 72 at the same timing in each molding cycle in the softening determination range stored in the softening determination range storage means 92. It is determined whether or not there is. FIG. 5 is a diagram showing the change over time of the sum of strains calculated by the first strain sum calculation means 74. In this embodiment, softening is determined using the sum of strains measured by the first strain sensor 36 and the second strain sensor 40 at the end of each molding cycle. In general, since no problems such as softening have occurred in the lower mold 12 before starting use, no residual strain has also occurred (that is, in the first strain sensor 36 and the second strain sensor 40, The amount of distortion “0” is measured). However, when the molding cycle is repeated, residual strain is generated in the lower mold 12 due to a thermal history applied to the lower mold 12. For example, at the time t1 when the first molding cycle ends, it is calculated from the sum of the calculated strains that a residual strain of Δd _t1 has occurred. The amount of residual strain increases as Δd _t2 ,..., Δd _{ti with} each molding cycle.

In the present embodiment, the presence / absence of softening of the lower mold 12 is determined using the softening ratio of the lower mold 12 calculated from the above-described sum of strains. FIG. 6 is a diagram showing the relationship between the softening determination range and the sum of strains. The softening ratio of the lower mold 12 is, for example, a value obtained by subtracting the sum of strains detected at the end of each molding cycle from the sum of strains detected at the start of use of the lower mold 12. It can be calculated by dividing by the sum of the distortions detected at the start of use.
The softening determination range storage means 92 stores a threshold value (reference value) of the softening ratio at which it is determined that softening has occurred, and the first determination means 90 includes the sum of the strain input for each molding cycle and the threshold value. And compare. For example, in the case of FIG. 6, the threshold value (reference value) is 40%, and it is determined that the threshold is within the softening determination range when the softening ratio of the sum of input strains is 40% or more. When it is determined that the sum of the input strains is within the softening determination range, a softening determination signal is input to the molding cycle control means 106.

When the softening determination signal is input to the molding cycle control means 106, a message indicating that the lower mold 12 has been softened is displayed on the monitor 22. Or when the control apparatus 20 is provided with alerting | reporting means, such as an alarm, you may alert | report the softening generation | occurrence | production of a shaping | molding die by an alerting | reporting means. When the softening determination signal is input to the molding cycle control unit 106, the molding cycle control unit 106 may stop the molding cycle.
The operator of the molding apparatus 2 can perform maintenance such as replacing the lower mold 12 at a timing when the occurrence of softening of the lower mold 12 is notified. For this reason, a molding cycle is not executed using the lower mold 12 that has been deformed due to softening. It is possible to prevent problems caused by the deformation of the lower mold 12 from occurring in the molded product. The yield rate of molded products can be improved.

The second determination unit 94 includes a filling progress determination range storage unit 96 and a filling completion determination range storage unit 98. The filling progress determination range storage unit 96 stores a filling progress determination range related to the sum of the strains calculated by the second strain sum calculation unit 80, and the filling completion determination range storage unit 98 includes the second strain sum calculation unit 80. The filling completion determination range relating to the calculated sum of strains is stored. The filling progress determination range is a range determined by the reference value of the extension strain generated in the second connecting plate 54 and the second beam pair 48 and 56. The filling completion determination range is a range determined by a reference value of compressive strain generated in the second connecting plate 54 and the second beam pair 48 and 56. The second determination means 90 inputs the sum of the strains calculated by the second strain sum calculation means 80 during the molding cycle by the molds 10 and 12, and determines whether or not the sum of the strains is within the filling progress determination range. To do. Then, after determining that the sum of the input strains is within the filling progress determination range, it is determined whether or not the input sum of strains is within the filling completion determination range. When it is determined that the sum of strains is within the filling completion determination range, a filling completion determination signal is input to the molding cycle control means 106.
When the filling completion determination signal is input to the molding cycle control means 106, the molding cycle control means 106 ends the pressurizing process and proceeds to a material solidification process. When it is determined that the filling is completed, the material flows to the bottom surface 12d of the lower mold 12. In addition to preventing the molded product from being thin, it is possible to keep the load applied to the lower mold 12 to a minimum.

The third determination unit 100 includes a filling progress determination range storage unit 102 and a filling completion determination range storage unit 104. The filling progress determination range storage unit 102 stores a filling progress determination range related to the strain difference calculated by the third strain difference calculation unit 88. The filling completion determination range storage unit 104 stores the filling progress determination range storage unit 104 by the third strain sum calculation unit 86. The filling completion determination range relating to the calculated sum of strains is stored. The filling progress determination range is a range determined by the reference value of the shear strain generated in the third connecting plate 66 and the third beam pair 62 and 70. The filling completion determination range is a range determined by the reference value of the compressive strain generated in the third connecting plate 66 and the third beam pair 62 and 70. The third determination means 100 inputs the sum of the strain and the strain difference calculated by the third calculation means 84 during the molding cycle by the molds 10 and 12, and determines whether or not the strain difference is within the filling progress determination range. judge. Then, it is determined whether or not the sum of strains input after determining that the input strain difference is within the filling progress determination range is within the filling completion determination range. When it is determined that the sum of strains is within the filling completion determination range, a filling completion determination signal is input to the molding cycle control means 106.
When the filling completion determination signal is input, the molding cycle control means 106 ends the pressurizing process and proceeds to a material solidification process. When it is determined that the filling is completed, the material flows to the bottom surface 12d of the lower mold 12. In addition to preventing the molded product from being thin, it is possible to keep the load applied to the lower mold 12 to a minimum.

  In the present embodiment, the measuring device 26 is provided on the bottom surface 12d of the lower mold 12 and the measuring device 57 is provided on the side surface 12f. However, by providing only one of the measuring devices, the lower mold 12 can also be provided. It is possible to satisfactorily determine the filling state of the material.

Next, processing for determining the material filling state using the measuring device 26 will be described. FIG. 7 is a diagram showing the change over time of the filling state of the material 110 into the lower mold 12, and FIG. 8 is a graph showing the change over time of the sum of the strain calculated by the second strain sum calculation means 80 and the filling state of the material. It is a figure showing a mode. When the molding cycle is started, the strain is measured by the second strain sensor 50 and the third strain sensor 54, respectively. The strains respectively measured by the second strain sensor 50 and the third strain sensor 54 are input to the second calculation means 78, and the second strain sum calculation means 80 calculates the sum of those strains. The calculated sum of distortions is sequentially input to the second determination means 94.
As shown in FIG. 7A, at the start of the molding cycle, the lower mold 12 is not yet filled with the material 110. At this time, the strains measured by the second strain sensor 50 and the third strain sensor 54 are both “0”, and the sum of strains calculated by the second strain sum calculation means 80 is also “0” (FIG. 8). (See time point (a)). Further, as shown in FIG. 7B, even when the material 110 is arranged in the lower mold 12 and the material 110 starts to flow into the recess 12 c of the lower mold 12, heat and force from the material 110 are also generated. Does not affect the second thin portion 44. As shown in FIG. 8, at the time of (b), there is no change in the sum of the strain measured by the second strain sensor 50 and the third strain sensor 54 and the strain calculated by the second strain sum calculation means 80. .

When the molding cycle proceeds and the material 110 flows into the recess 12c and approaches the second thin portion 44 (that is, the bottom surface 12d of the lower mold 12) as shown in FIG. 7C, the second thin portion 44 is obtained. The heat from the material 110 is applied from the direction indicated by the arrow. When the high-temperature heat is transmitted, the second thin portion 44 expands, bends upward, and deforms evenly. Along with this, the second beam pair 48, 56 is deformed in a direction in which the respective distal end portions are separated from each other, and the second connecting plate 52 is bent toward the side away from the second thin portion 44, and evenly. Deform. That is, the measuring device 43 is deformed in a direction in which the second beam pair 48 and 56 is pulled by the bending of the second thin portion 44 and the second connecting plate 52. The second strain sensor 50 and the third strain sensor 54 are displaced in the same direction together with the bending of the second connecting plate 52, and the tensile strain generated thereby is measured. The strain measured by the second strain sensor 50 and the strain measured by the third strain sensor 54 are both positive sign strain amounts. The second strain sum calculation means 80 can calculate the sum of these strains and obtain the sum of the extension strains generated in the second connecting plate 52. As shown in the vicinity of the time point (c) in FIG. 8, the sum of the stretching strain increases as the material 110 approaches the second thin portion 44.
The second determination means 94 compares the above-described sum of strains with the reference value α of the filling progress determination range stored in the filling progress determination range storage means 96, and the sum of the input strains is greater than or equal to the reference value α. (That is, whether or not the sum of the input strains is within the filling progress determination range).

  As shown in FIG. 7D, when the molding cycle further proceeds and the flowing material 110 comes into contact with the surface of the second thin portion 44 (that is, the bottom surface 12e of the lower mold 12), the material 110 adds the material. Due to the applied pressure, the second thin portion 44 that has been bent upward is pushed back downward. The second thin portion 44 is rapidly deformed in a direction opposite to that immediately after the material comes into contact with the second thin portion. Accordingly, the second beam pair 48 and 56 is deformed in a direction in which the respective distal end portions approach each other, and the second connecting plate 52 is deformed so as to bend toward the side approaching the second thin portion 44. That is, the measuring device 43 is deformed in a direction in which the second beam pair 48 and 56 is compressed by the bending of the second thin portion 44 and the second connecting plate 52. The second strain sensor 50 and the third strain sensor 54 measure the strain caused by the change in the bending of the second connecting plate 52 described above.

Until the material 110 comes into contact with the second thin portion 44, both the second strain sensor 50 and the third strain sensor 54, which have both measured the positive strain, measure the negative strain. That is, the second distortion sum calculation means 80 calculates the sum of compression distortions having a magnitude in the negative sign direction. As shown in the vicinity of the time point (d) in FIG. 8, the compressive strain rapidly increases in the direction of the negative sign after the material 110 contacts the second thin portion 44.
In the second determination means 94, the above-described sum of strains is compared with the reference value β of the filling completion determination range stored in the filling completion determination range storage means 98, and the input strain sum is equal to or greater than the reference value β. (That is, whether or not the sum of the input strains is within the filling completion determination range).
When it is determined that the sum of the input strains is equal to or greater than the reference value β (that is, the sum of the input strains is within the filling completion determination range), a filling completion determination signal is input to the molding cycle processing means 106 and filling is performed. Completion is displayed on the monitor 22. The molding cycle control means 106 ends the pressurizing process and proceeds to the next molding process step.

  Next, processing for determining a material filling state using the measuring device 57 will be described. FIG. 9 is a diagram showing the change over time of the filling state of the material 110 into the lower mold 12, and FIG. 10 is a graph showing the sum of strain and the difference between the strains calculated by the third calculation means 84 and the filling state of the material over time. It is a figure showing the mode of change. When the molding cycle is started, the fifth strain sensor 64 and the sixth strain sensor 68 respectively measure strain. The strain measured by the fifth strain sensor 64 and the sixth strain sensor 68 is input to the third calculation means 84. In the third calculation means 84, the third distortion sum calculation means 86 calculates the sum of those distortions, and the third distortion difference calculation means 88 calculates the difference between these distortions. The calculated distortion sum and distortion difference are sequentially input to the third determination means 100.

As shown in FIG. 9A, at the start of the molding cycle, the lower mold 12 is not yet filled with the material 110. At this time, the strains measured by the fifth strain sensor 64 and the sixth strain sensor 68 are both “0”, and the sum and strain difference of the strains calculated by the third calculation unit 84 are also “0” ( (See (a) of FIG. 10).
Next, as shown in FIG. 9 (b), at the initial stage where the material 110 is arranged on the lower mold 12 and the material 110 starts to flow into the recess 12 c of the lower mold 12, The heat from the material 110 is applied from the direction indicated by the arrow. When the high-temperature heat is transmitted, the upper portion of the third thin portion 58 expands. The upper part and the lower part of the third thin part 58 bend in opposite directions, and the third thin part 58 deforms oddly. Accordingly, the third beam portion pair 62, 70 is inclined in the same direction, and the upper and lower portions of the third connecting plate 66 are in the same direction as the upper and lower portions of the third thin portion 58. Bends and deforms oddly. The fifth strain sensor 64 and the sixth strain sensor 68 are displaced in opposite directions together with the bending generated in the lower portion and the upper portion of the third connecting plate 66. The fifth strain sensor 64 measures a negative sign distortion, and the sixth strain sensor 68 measures a positive sign distortion. As shown in FIG. 10 (b), the third strain difference calculation means 88 can calculate the difference between these strains to obtain the shear strain generated in the third connecting plate 66. At this stage, the third strain sum calculation means 86 calculates a sum of strains that approximates to zero.

  When the molding cycle proceeds and the material 110 further flows into the recess 12c and contacts the upper portion of the third thin portion 58, as shown in FIG. 9C, the upper portion of the third thin portion 58 has the material Heat from 110 and frictional force from the direction indicated by the arrow are applied. By applying high-temperature heat and a force in a direction parallel to the third thin portion 58 to the upper portion of the third thin portion 58, the upper portion and the lower portion of the third thin portion 58 are opposite to each other. It bends and deforms oddly. Accordingly, the third beam pair 62, 70 is inclined in the same direction, and the upper portion and the lower portion of the third connecting plate 66 are also the same as the upper portion and the lower portion of the third thin portion 58. Bends in the direction and deforms oddly. The fifth strain sensor 64 and the sixth strain sensor 68 are displaced in opposite directions together with the bending generated in the lower portion and the upper portion of the third connecting plate 66. The fifth strain sensor 64 measures the positive sign distortion, and the sixth strain sensor 68 measures the negative sign distortion. As shown in FIG. 10 (c), the third strain difference calculation means 88 can calculate the difference between these strains and obtain the shear strain generated in the third connecting plate 66. At the time point (c), a shear strain larger than the shear strain generated in the third connecting plate 66 by the heat at the previous time point (b) is calculated. Even at this stage, the third strain sum calculation means 86 calculates the sum of strains that approximates zero.

  As shown in FIG. 10, the third determination unit 100 first inputs the difference between the strain and the reference value α of the filling progress determination range stored in the filling progress determination range storage unit 102. It is determined whether or not the difference between the strains exceeds the reference value α (that is, whether or not the input strain difference is within the filling progress determination range). If it is determined that the input strain difference is greater than or equal to the reference value α, it is then determined whether or not the input strain difference is now greater than or equal to the reference value α ′. As shown in FIG. 10, a reference value α and a reference value α ′ are set in accordance with the calculated sign of the shear strain, and after the shear strain caused by heat exceeds the reference value α, the heat and friction force It can be determined that the shear strain caused by the value exceeds the reference value α ′. Alternatively, one reference value may be set for the absolute value of the strain difference input to the third determination unit 100 to determine whether or not the input strain difference is within the filling progress determination range. Good.

As shown in FIG. 9D, when the molding cycle further proceeds and the flowing material 110 comes into contact with the bottom surface 12e of the lower mold 12, the frictional force applied to the third thin portion 58 is reduced. . At the same time, the third thin-walled portion 58 is deformed so as to be bent toward the third connecting plate 66 by the pressure applied perpendicularly from the material 110. That is, the third thin portion 58 is deformed in a direction to be compressed toward the third connecting plate 66 side immediately after the material comes into contact with the bottom surface 12e. Along with this, the third beam pair 62, 70 is deformed in a direction in which the respective distal end portions approach each other, and the third connecting plate 66 is deformed so as to be bent toward the third thin portion 58 side. That is, the measuring device 457 is deformed in a direction in which the third beam pair 62 and 70 are compressed by the bending of the third thin portion 58 and the third connecting plate 66. The fifth strain sensor 64 and the sixth strain sensor 68 measure the compressive strain caused by the change in the bending of the third connecting plate 66 described above. That is, the fifth strain sensor 64 and the sixth strain sensor 68 both measure the negative sign strain.
The third distortion sum calculation means 86 calculates the sum of compression distortions having a magnitude in the negative sign direction. At this time, the third strain difference calculation means 88 calculates a strain difference that approximates to zero. As shown in the vicinity of the time point (d) in FIG. 10, the compressive strain rapidly increases in the direction of the negative sign after the material 110 contacts the bottom surface 12e.

As shown in FIG. 10, the third determination unit 100 compares the sum of the strains described above with the reference value β of the filling completion determination range stored in the filling completion determination range storage unit 104 and inputs the input distortion. It is determined whether or not the sum of the values is equal to or greater than the reference value β (that is, whether or not the sum of the input strains is within the filling completion determination range).
When it is determined that the sum of the input strains is equal to or greater than the reference value β (that is, the sum of the input strains is in the filling completion determination range), a filling completion determination signal is input to the molding cycle control means 106 and filling is performed. Completion is displayed on the monitor 22. The molding cycle control means 106 ends the pressurizing process and proceeds to the next molding process step.

As described above, when the measuring device 43 is used, the sum of strains input to the second determination means 94 during a predetermined period after the molding cycle is started is “0”. However, due to the sensitivity of the second strain sensor 50 and the third strain sensor 54, vibration applied to the molding apparatus 2, etc., noise as shown in FIG. 8 is generated in the sum of strains input to the second determination means 94. Sometimes.
Even when the measuring device 57 is used, the sum of strains and the strain difference input to the third determination means 100 during a predetermined period after the start of the molding cycle are “0”. However, depending on the sensitivity of the fifth strain sensor 64 and the sixth strain sensor 68, the vibration applied to the molding apparatus 2, etc., the sum of strains input to the third determination means 100 and the difference in strains are as shown in FIG. Noise may occur.

  Temporarily, the filling state of the lower mold 12 of the material 110 is determined only by whether or not the sum of strains input to the second determination unit 94 (or the third determination unit 100) exceeds a predetermined reference value β. In such a case, when the sum of distortions caused by noise becomes larger than the reference value β, it may be erroneously determined that the filling is completed. According to the method of the present embodiment, after it is determined that the sum of strains that are continuously input (in the case of the third determination unit 100, the difference in strain) is within the filling progress determination range, Further, it is determined whether or not the sum of strains input continuously is within the filling completion determination range. Misjudgments caused by noise as described above can be prevented well.

  In the above embodiment, the filling progress determination range is determined by the predetermined reference values α and α ′, and the filling completion determination range is determined by the predetermined reference value β. However, the present invention is not limited to this. For example, the filling progress determination range and the filling completion determination are performed based on the reference value regarding the change rate and change direction with time of the sum of strains and / or the difference of strains input to the second determination unit 94 (or the third determination unit 100). A range may be determined.

In the above embodiment, the case where the measuring devices 26, 43, and 57 are provided in the concave portion 12c of the lower mold 12 has been described, but the present invention is not limited to this. For example, you may provide a measuring device in the other place of the lower mold 12. Alternatively, a measuring device may be provided on the upper mold 10 side.
In the above embodiment, hot forging in which a material is heated to form is described, but the present invention is not limited to this. For example, even in the case of cold forging, the frictional heat and plastic deformation heat of the material can be measured with a strain sensor to determine the filling state of the material.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

The figure showing the structure of the shaping | molding apparatus which concerns on one Example of this invention. Partial sectional view of the surface 12d of the molding apparatus of FIG. 1 is a partial cross-sectional view of the recess 12c of the molding apparatus of FIG. Block diagram showing electrical processing system of molding apparatus The figure showing the time-dependent change of the sum of the distortion calculated by the first distortion sum calculation means Diagram showing the relationship between the softening judgment range and the sum of strains Diagram showing the change over time of the filling condition of the material into the mold The figure showing the mode of a time-dependent change of the sum of the distortion which the 2nd distortion sum calculation means calculated, and the filling condition of a raw material Diagram showing the change over time of the filling condition of the material into the mold The figure showing the mode of a time-dependent change of the sum of distortion calculated by the 3rd calculation means, the difference of distortion, and the filling condition of a raw material.

Explanation of symbols

2: Molding device 4, 16: Shaft 6, 18: Cylinder 8, 14: Support base 10, 12: Mold 12a, 12b, 12c: Recess 12d: Molding surface 12e: Bottom surface 12f: Side surface 20: Control device 22: Monitor 24: input means 26, 43, 57: measuring devices 28, 45, 59: back surface 29: first thin portions 32, 46, 60: cavity 34, 42: first beam portion pair 36: first strain sensor 38: first 1 connection plate 40: second strain sensor 44: second thin portion 48, 56: second beam portion pair 50: third strain sensor 52: second connection plate 54: fourth strain sensor 58: third thin portion 62, 70: third beam portion pair 64: fifth strain sensor 66: third connecting plate 68: sixth strain sensor 72: first calculation means 74: first strain sum calculation means 76: first strain difference calculation means 78: first 2 calculation means 80: second distortion sum calculation means 82: second distortion difference calculation means 84: second Calculation means 86: third strain sum calculation means 88: third strain difference calculation means 90: first determination means 92: softening determination range storage means 94: second determination means 96, 102: filling progress determination range storage means 98, 104 : Filling completion determination range storage means 100: third determination means 106: molding cycle control means 111: aperture

Claims (8)

A thin first thin portion provided on a part of a molding surface of a mold for forming the material in contact with the material;
A first beam portion pair extending parallel to each other from the anti-molding surface of the first thin portion;
A first connecting portion extending between the first beam portion pair;
A first strain sensor that measures strain generated in the first connecting portion on one side of the first beam portion pair;
A second strain sensor for measuring strain generated in the first connecting portion on the other side of the first beam portion pair;
First strain sum calculation means for calculating a sum of strains measured by the first strain sensor and the second strain sensor;
First strain difference calculating means for calculating a difference in strain measured by the first strain sensor and the second strain sensor;
The softening determination range of the mold related to the sum of strains calculated by the first strain sum calculation means and / or the difference of strains calculated by the first strain difference calculation means is stored, For each molding cycle, the sum of strains calculated by the first strain sum calculation means and / or the difference of strains calculated by the first strain difference calculation means at the same timing in each molding cycle was input and input. First determination means for determining whether or not a sum of strains and / or a difference in strain is within a stored softening determination range;
A sensing device comprising: A thin second thin portion provided in a portion of the molding surface where the material flows substantially vertically during molding;
A second beam portion pair extending in parallel with each other from the anti-molding surface of the second thin portion;
A second connecting portion extending between the second beam portion pair;
A third strain sensor that measures strain generated in the second connecting portion on one side of the second beam portion pair;
A fourth strain sensor that measures strain generated in the second coupling portion on the other side of the second beam portion pair;
Second strain sum calculating means for calculating a sum of strains measured by the third strain sensor and the fourth strain sensor;
A filling progress judgment range and a filling completion judgment range due to material flow of the material related to the sum of strains calculated by the second strain sum calculation means are stored, and the second strain sum calculation means is stored during a molding cycle by the mold. After inputting the calculated sum of strains over time and determining that the input sum of strains is within the stored filling progress determination range, whether or not the input sum of strains is within the filling completion determination range. A second determination means for determining;
The filling progress determination range indicates a range when the second connecting portion bends away from the second thin portion,
The filling completion determination range indicates a range when the second connecting portion bends to the side approaching the second thin portion.
The sensing device according to claim 1. A thin third thin portion provided in a portion of the molding surface where the material flows substantially in parallel during molding;
A third beam portion pair extending in parallel with each other from the anti-molding surface of the third thin portion;
A third connecting portion extending between the third beam portion pair;
A fifth strain sensor for measuring strain generated in the third connecting portion on one side of the third beam portion pair;
A sixth strain sensor for measuring strain generated in the third connecting portion on the other side of the third beam portion pair;
Third strain sum calculating means for calculating a sum of strains measured by the fifth strain sensor and the sixth strain sensor;
Third strain difference calculating means for calculating a difference in strain measured by the fifth strain sensor and the sixth strain sensor;
The filling completion determination range by the material flow of the material related to the sum of strains calculated by the third strain sum calculation means and the filling progress determination range by the material flow of the materials related to the strain difference calculated by the third strain difference calculation means are stored. The difference between the strains calculated by the third strain sum calculation means and the strain difference calculated by the third strain difference calculation means over time during the molding cycle of the mold. Third determination means for determining whether or not the sum of the input strains is in the stored filling completion determination range after determining that it is in the stored filling progress determination range;
The sensing device according to claim 1, further comprising: A part of a molding surface of a molding die that contacts the material to form the material, and a thin second thin portion provided in a portion where the material flows substantially vertically at the time of molding;
A second beam portion pair extending in parallel with each other from the anti-molding surface of the second thin portion;
A second connecting portion extending between the second beam portion pair;
A third strain sensor that measures strain generated in the second connecting portion on one side of the second beam portion pair;
A fourth strain sensor that measures strain generated in the second coupling portion on the other side of the second beam portion pair;
Second strain sum calculating means for calculating a sum of strains measured by the third strain sensor and the fourth strain sensor;
A filling progress judgment range and a filling completion judgment range due to material flow of the material related to the sum of strains calculated by the second strain sum calculation means are stored, and the second strain sum calculation means is stored during a molding cycle by the mold. After inputting the calculated sum of strains over time and determining that the input sum of strains is within the stored filling progress determination range, whether or not the input sum of strains is within the filling completion determination range. A second determination means for determining,
The filling progress determination range indicates a range when the second connecting portion bends away from the second thin portion,
The filling completion determination range indicates a range when the second connecting portion bends to the side approaching the second thin portion.
Sensing device characterized by that. A part of the molding surface of the molding die for molding the material in contact with the material, the third thin portion of the thin wall provided in the portion where the material flows substantially parallel during molding,
A third beam portion pair extending in parallel with each other from the anti-molding surface of the third thin portion;
A third connecting portion extending between the third beam portion pair;
A fifth strain sensor for measuring strain generated in the third connecting portion on one side of the third beam portion pair;
A sixth strain sensor for measuring strain generated in the third connecting portion on the other side of the third beam portion pair;
Third strain sum calculating means for calculating a sum of strains measured by the fifth strain sensor and the sixth strain sensor;
Third strain difference calculating means for calculating a difference in strain measured by the fifth strain sensor and the sixth strain sensor;
The filling completion determination range by the material flow of the material related to the sum of strains calculated by the third strain sum calculation means and the filling progress determination range by the material flow of the materials related to the strain difference calculated by the third strain difference calculation means are stored. The difference between the strains calculated by the third strain sum calculation means and the strain difference calculated by the third strain difference calculation means over time during the molding cycle of the mold. Third determination means for determining whether or not the sum of the input strains is in the stored filling completion determination range after determining that it is in the stored filling progress determination range;
A sensing device comprising: A first thin-walled portion provided on a part of a molding surface of a molding die that contacts the material and molding the material; and a first beam portion pair extending in parallel to each other from the anti-molding surface of the first thin-walled portion. A first connecting portion extending between the first beam portion pair, a first strain sensor for measuring strain generated in the first connecting portion on one side of the first beam portion pair, and the first connecting portion. A method of determining softening of the mold using a sensing device including a second strain sensor that measures strain generated in a portion on the other side of the first beam portion pair,
A first strain sum calculation step of calculating a sum of strains measured by the first strain sensor and the second strain sensor at the same timing in each molding cycle for every one or a plurality of molding cycles by the molding die; ,
A first strain difference calculation step of calculating a difference in strain measured by the first strain sensor and the second strain sensor at the same timing in each molding cycle for each one or a plurality of molding cycles by the mold; ,
Whether the sum of strains calculated in the first strain sum calculation step and / or the difference in strains calculated in the first strain difference calculation step is within a preset softening determination range of the mold. A first determination step for determining;
A method for determining softening of a mold comprising: A part of the molding surface of the molding die for molding the material in contact with the material, the second thin-walled portion provided in the portion where the material flows substantially vertically during molding, and the reaction between the second thin-walled portion A second pair of beam portions extending in parallel with each other from the molding surface, a second connecting portion extending between the second pair of beam portions, and a strain generated in the second connecting portion. Of the material to the mold using a sensing device comprising a third strain sensor for measuring on the side and a fourth strain sensor for measuring the strain generated in the second connecting portion on the other side of the second beam portion pair. A method for determining the filling status due to material flow,
A second strain sum calculation step of calculating, over time, a sum of strains measured by the third strain sensor and the fourth strain sensor during a molding cycle by the mold;
After determining that the sum of the strains calculated in the second strain calculation step is within a filling progress determination range due to the material flow of a preset material, the filling completion determination range due to the material flow of the material is set in advance. A second determination step of determining whether or not there is,
The filling progress determination range indicates a range when the second connecting portion bends away from the second thin portion,
The filling completion determination range indicates a range when the second connecting portion bends to the side approaching the second thin portion.
The filling condition determination method characterized by the above-mentioned. A part of a molding surface of a molding die that contacts the material to form the material, and a thin third thin part provided in a part where the material flows substantially in parallel during molding, and a reaction between the third thin part and the third thin part A third beam portion pair extending in parallel with each other from the molding surface; a third connecting portion extending between the third beam portion pair; and a strain generated in the third connecting portion. The material for the mold using a sensing device including a fifth strain sensor for measuring on one side and a sixth strain sensor for measuring the strain generated in the third connecting portion on the other side of the third beam pair. A method for determining the filling status due to the material flow of
A third strain sum calculation step of calculating, over time, a sum of strains measured by the fifth strain sensor and the sixth strain sensor during a molding cycle by the mold;
A third strain difference calculating step of calculating, over time, a difference between strains measured by the fifth strain sensor and the sixth strain sensor during a molding cycle by the mold;
After determining that the difference in strain calculated in the third strain difference calculation step is within a filling progress determination range due to material flow of a preset material, the sum of strains calculated in the third strain sum calculation step A third determination step for determining whether or not is in a filling completion determination range due to material flow of a preset material;
A filling state determination method comprising:

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