Mold apparatus

Abstract

To provide a technique capable of easily measuring the transmittance of a resin at the time of molding and the change with time of the resin temperature at that time.SOLUTION: The mold device 1 includes a mold 2 having a molding-space s1 into which resins are injected and supplied, a light projecting unit 4 provided on a first inner surface 21 of the molding-space s1 and configured to project infrared light into the molding-space s1, a light receiving unit 6 provided on a second inner surface 22 facing the first inner surface 21 in the molding-space s1, and a measuring unit 8 configured to measure the light received by the light receiving unit 6.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a mold apparatus. [Background technology]

[0002] Patent Document 1 discloses a temperature sensor pin provided in a mold. The temperature sensor pin is inserted into a through-hole in the mold and is used to measure the temperature of an object to be measured inside the mold. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-113738 Summary of the Invention [Problem to be solved by the invention]

[0004] The sensor pin receives infrared light emitted from the object to be measured. The received infrared light is converted by the measuring unit into information indicating the temperature of the object to be measured. In other words, the sensor pin constitutes a part of the radiation thermometer. A radiation thermometer is used to measure the change in temperature of a target object over time, which is used to evaluate the quality of the target object.

[0005] A resin composition is used as the object to be measured using a radiation thermometer. Resin compositions vary in apparent color and light transmittance depending on the type of resin and the type and amount of additives, such as reinforcing agents and antioxidants. When measuring the temperature change over time of a resin using a radiation thermometer, due to the difference in transmittance between the two types of resin compositions, the surface temperature of the first resin composition is primarily measured, while the internal temperature of the second resin composition is measured in addition to the surface temperature compared to the first resin composition. Measuring the temperature change over time of a resin composition as the object to be measured in a mold using a radiation thermometer does not reveal which part of the object to be measured is at that temperature. It is expected that the change in temperature of a resin composition over time can be accurately estimated by taking the transmittance of the resin composition into consideration. To this end, it is necessary to understand the relationship between the transmittance of the resin composition during molding, the measurement data of the resin composition using a radiation thermometer, and the change in the surface temperature and internal temperature of the resin composition over time. Therefore, a method is desired for easily measuring the transmittance of the resin during molding and the change in the resin temperature over time. [Means for solving the problem]

[0006] The mold device of this embodiment comprises a mold having a molding space into which resin is injected, a first light-emitting unit provided on a first inner surface of the molding space and emitting infrared light into the molding space, a first light-receiving unit provided on a second inner surface opposite the first inner surface in the molding space, and a measuring unit that measures the light received by the first light-receiving unit. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to easily measure the transmittance of a resin during molding and the change in the resin temperature over time at that time. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing an example of a mold device according to a first embodiment. [Figure 2] FIG. 2 is a diagram showing the shape of the emission space. [Figure 3] FIG. 3 is a cross-sectional view taken along line II-II in FIG. [Figure 4A] FIG. 4A is a diagram for explaining the range in which the light-receiving surface is located relative to the light-projecting surface. [Figure 4B] FIG. 4B is a diagram showing an example of the positional relationship between the light projection surface and the light receiving surface on the XY plane. [Figure 5] FIG. 5 is a graph showing an example of the results of determining transmittance by spectrally separating transmitted light. [Figure 6]FIG. 6 is a graph showing the change in resin temperature over time as measured based on the emitted light. [Figure 7] FIG. 7 is a cross-sectional view of a mold of a mold device according to the second embodiment. [Figure 8A] FIG. 8A is a cross-sectional view of a mold of a mold device according to a third embodiment. [Figure 8B] FIG. 8B is a cross-sectional view of a mold of a mold device according to a modified example of the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] First, the contents of the embodiment will be listed and explained. [Outline of the embodiment] In the course of their research into the molding of optically transparent resins, the present inventors discovered a correlation between the transparency of the resin as a state and the change in resin temperature over time, leading to the invention of the mold apparatus disclosed herein as a way to easily measure this correlation.

[0010] (1) An embodiment of a mold device includes a mold having a molding space into which resin is injected, a first light-emitting unit provided on a first inner surface of the molding space and emitting infrared light into the molding space, a first light-receiving unit provided on a second inner surface in the molding space opposite the first inner surface, and a measuring unit that measures the light received by the first light-receiving unit. According to the above configuration, during injection molding, light emitted from the first light-emitting unit passes through the resin in the molding space and reaches the first light-receiving unit. Therefore, the first light-receiving unit can receive transmitted light that has passed through the resin. The transmitted light can be used to determine the transmittance of the resin portion through which the light has passed. Furthermore, if the first light-emitting unit stops emitting infrared light, the first light-receiving unit can receive radiant light emitted from the resin. The radiant light can be used to determine the temperature of the resin portion. Therefore, the measuring unit can obtain both the transmittance and the temperature from approximately the same portion of the resin. As a result, it is possible to obtain the change in resin temperature over time when molding a resin with a specific transmittance, and it is possible to easily measure the transmittance of the resin during molding and the change in the temperature of the resin over time at that time.

[0011] (2) In the mold device of (1) above, the first light-projecting unit has a light-projecting surface exposed to the first inner surface, and the first light-receiving unit has a light-receiving surface exposed to the second inner surface, and in a cross section including a center line perpendicular to the center point of the light-projecting surface of the first inner surface, when at least a portion of the light-receiving surface is located between a pair of intersection points where a pair of equal sides of an isosceles triangle having the center point as its vertex and the center line as its center intersect with the second inner surface, the apex angle of the isosceles triangle may be 45 degrees or less. If the apex angle is greater than 45 degrees, the light receiving surface may have difficulty receiving transmitted light if the light projecting surface and the light receiving surface are offset by the maximum distance. If the apex angle is 45 degrees or less, the light receiving surface can properly receive transmitted light even if the light projecting surface and the light receiving surface are offset by the maximum distance.

[0012] (3) In the mold device of (2) above, the apex angle of the isosceles triangle may be 30 degrees or less.

[0013] (4) In the mold device of (2) or (3) above, the apex angle of the isosceles triangle may be 15 degrees or less.

[0014] (5) Furthermore, in any one of the mold devices (1) to (4) above, when the first light-projecting unit has a light-projecting surface exposed to the first inner surface and the first light-receiving unit has a light-receiving surface exposed to the second inner surface, the light-projecting surface and the light-receiving surface may have an overlapping region that overlaps with each other when the first inner surface is viewed in a plane. In this case, the light-emitting surface and the light-receiving surface are substantially opposite to each other, and the transmitted light can be appropriately received by the light-receiving surface.

[0015] (6) In addition, in any one of the mold apparatuses (1) to (5) above, the measurement unit The device may have a spectrometer that separates the light received by the first light receiving unit, a radiation thermometer that measures the temperature based on the light received by the first light receiving unit, and a switching unit that guides the light received by the first light receiving unit to either the spectrometer or the radiation thermometer. In this case, the transmitted light and the emitted light can be received and measured by one light receiving unit.

[0016] (7) Furthermore, in any one of the mold devices (1) to (6) above, when the mold has a first through hole communicating the first inner surface with the outside of the mold and a second through hole communicating the second inner surface with the outside of the mold, and the first light-projecting unit has a first optical fiber inserted into the first through hole and guiding infrared light emitted from a light source outside the mold to the first inner surface, the light-receiving unit may have a light-receiving surface exposed to the second inner surface and a second optical fiber inserted into the second through hole and guiding light received at the light-receiving surface to the measurement unit. In this case, infrared light from a light source outside the mold is guided to the molding space via a first optical fiber, and light emitted from the resin is guided to the outside of the mold via a second optical fiber.

[0017] (8) Furthermore, any one of the mold devices (1) to (7) above may further include a second light-emitting unit provided on a third inner surface of the molding space to project infrared light into the molding space, and a second light-receiving unit provided on a fourth inner surface facing the third inner surface in the injection space. In this case, it is possible to measure the transmittance and temperature of a resin portion in the molding space that is different from the resin portion whose transmittance and temperature are measured by the first light receiving unit, thereby making it possible to measure the temperature changes over time of multiple resin portions that are in different states in a single molding run.

[0018] (9) In the mold device of (8) above, the distance between the first inner surface and the second inner surface may be different from the distance between the third inner surface and the fourth inner surface. In this case, the transmittance of the resin portion to be measured by the first light receiving unit is different from the transmittance of the resin portion to be measured by the second light receiving unit, and therefore, the temperature change over time of multiple resin portions having different transmittances can be measured in a single molding operation.

[0019] [Details of the embodiment] Preferred embodiments will now be described with reference to the drawings.

[0020] [About the mold equipment] FIG. 1 is a cross-sectional view showing an example of a mold device according to a first embodiment. The mold device 1 includes a mold 2, a plurality of light projecting units 4, a plurality of light receiving units 6, and a plurality of measuring units 8.

[0021] The mold 2 has an injection space S. The injection space S is a space into which resin is injected and supplied. The injection space S has a molding space s1. The molding space s1 is a space in which a molded product is formed. The molded product is formed by the resin injected and supplied into the injection space S. The molded product is a strip-shaped, elongated member. The molded product has a shape whose thickness gradually decreases from one end to the other end. Therefore, the molding space s1 is an elongated space. The molding space s1 is also a space whose thickness gradually decreases along the longitudinal direction. The mold device 1 has a function of measuring the transmittance of the resin filled in the molding space s1 and the change in the temperature of the resin over time.

[0022] In the following description, the three mutually orthogonal directions in each drawing are defined as the X direction, Y direction, and Z direction. The first side of the X direction is defined as the X1 direction, and the second side of the X direction is defined as the X2 direction. The first side of the Y direction is defined as the Y1 direction, and the second side of the Y direction is defined as the Y2 direction. The first side of the Z direction is defined as the Z1 direction, and the second side of the Z direction is defined as the Z2 direction. In this embodiment, the longitudinal direction of the molding space s1 is along the X direction. In addition, the direction from the thick end to the thin end of the molding space s1 is the X1 direction. The width direction of the molding space s1 is along the Y direction.

[0023] The mold 2 has a first mold portion 2a and a second mold portion 2b. An injection space S is provided between the first mold portion 2a and the second mold portion 2b. Fig. 2 is a diagram showing the shape of the injection space S. As shown in Fig. 2, the injection space S has a molding space s1, as well as a sprue s2, a runner s3, a gate portion s4, and a recess portion s5. The nozzle for injecting the resin is connected to the tip of the sprue s2. The resin to be injected into the injection space S is filled from the sprue s2 and supplied to each part. Examples of resins that can be injected into the injection space S include polyamide, polyphenylene sulfide, and polybutylene terephthalate. The resin that has passed through the sprue s2 passes through the runner s3 and reaches the gate s4. The resin passes through the gate portion s4 and is supplied to the molding space s1. The relief portion s5 is provided adjacent to the end of the molding space s1 in the X1 direction. The resin that reaches the end of the molding space s1 in the X1 direction flows into the relief portion s5. By the resin flowing into the relief portion s5, the flow of resin near the end of the molding space s1 in the X1 direction is regulated.

[0024] 1 shows a cross section of the molding space s1 along the XZ plane, and therefore shows a longitudinal cross section of the molding space s1. 1 and 2, the molding space s1 is a long and narrow space extending along the X direction. The molding space s1 is strip-shaped with a thickness in the Z direction. The thickness of the molding space s1 in the Z direction gradually decreases from the gate portion s4 side toward the X1 direction. The molding space s1 has a first space s11, a second space s12, and a third space s13. The first space s11, the second space s12, and the third space s13 are aligned in order along the X1 direction, that is, the resin flow direction.

[0025] The first space s11 is located at the end of the molding space s1 on the X2 direction side. The thickness of the first space s11 in the Z direction is the largest compared to the thicknesses of the other spaces s12 and s13 in the Z direction. The width of the first space s11 in the Y direction is the largest compared to the widths of the other spaces s12 and s13 in the Y direction. When viewed from above in the Z direction, the end of the first space s11 on the X1 direction side has a tapered shape that smoothly connects to the second space s12. The second space s12 is adjacent to the first space s11 in the X1 direction. The thickness of the second space s12 in the Z direction is thinner than the thickness of the first space s11 in the Z direction and thicker than the thickness of the third space s13 in the Z direction. The second space s12 has a rectangular shape in the XY plane. The third space s13 is provided between the second space s12 and the recess s5. The thickness of the third space s13 in the Z direction is thinner than the thickness of the second space s12 in the Z direction. The width of the third space s13 in the Y direction is the same as the width of the second space s12 in the Y direction. Like the second space s12, the third space s13 also has a rectangular shape in the XY plane.

[0026] As shown in FIG. 1, the inner surfaces of the first space s11 include a first inner surface 21 and a second inner surface 22. The first inner surface 21 is a plane parallel to the XY plane. The first inner surface 21 is provided on a surface of the first mold portion 2a facing the Z2 direction. The second inner surface 22 is a plane facing and parallel to the first inner surface 21 in the Z direction. The second inner surface 22 is a plane parallel to the XY plane. The second inner surface 22 is provided on a surface of the second mold portion 2b facing the Z1 direction.

[0027] The inner surfaces of the second space s12 include a third inner surface 23 and a fourth inner surface 24. The third inner surface 23 is a flat surface parallel to the XY plane. The third inner surface 23 is provided on the surface of the first mold portion 2a facing the Z2 direction. The fourth inner surface 24 is a surface that faces the third inner surface 23 in the Z direction and is parallel to it. The fourth inner surface 24 is a surface that is parallel to the XY plane. The fourth inner surface 24 is provided on the surface of the second mold portion 2b facing the Z1 direction. As described above, the thickness of the second space s12 in the Z direction is thinner than the thickness of the first space s11 in the Z direction. Therefore, the distance in the Z direction between the third inner surface 23 and the fourth inner surface 24 is smaller than the distance in the Z direction between the first inner surface 21 and the second inner surface 22.

[0028] The inner surfaces of the third space s13 include a fifth inner surface 25 and a sixth inner surface 26. The fifth inner surface 25 is a plane parallel to the XY plane. The fifth inner surface 25 is provided on the surface of the first mold portion 2a facing the Z2 direction. The sixth inner surface 26 is a plane facing and parallel to the fifth inner surface 25 in the Z direction. The sixth inner surface 26 is a plane parallel to the XY plane. The sixth inner surface 26 is provided on the surface of the second mold portion 2b facing the Z1 direction. As described above, the thickness of the third space s13 in the Z direction is thinner than the thickness of the second space s12 in the Z direction. Therefore, the distance in the Z direction between the fifth inner surface 25 and the sixth inner surface 26 is smaller than the distance in the Z direction between the third inner surface 23 and the fourth inner surface 24.

[0029] As shown in Figures 1 and 2, the mold 2 has a first through hole 31, a second through hole 32, a third through hole 33, a fourth through hole 34, a fifth through hole 35, a sixth through hole 36, a seventh through hole 37, an eighth through hole 38, and a ninth through hole 39. The through holes 31, 32, 34, 35, 37, and 38 are provided in the first mold part 2a, and the through holes 33, 36, and 39 are provided in the second mold part 2b.

[0030] The through holes 31, 32, and 33 are cylindrical holes that communicate between the first space s11 and the outside of the mold 2. The through holes 34, 35, and 36 are cylindrical holes that communicate between the second space s12 and the outside of the mold 2. The through holes 37, 38, and 39 are cylindrical holes that communicate between the third space s13 and the outside of the mold 2.

[0031] 1, the plurality of light projecting units 4 are provided in through holes 31, 34, and 37. The plurality of light receiving units 6 are provided in through holes 33, 36, and 39. The plurality of temperature sensors 10 are provided in the through holes 32, 35, and 38.

[0032] Fig. 3 is a cross-sectional view taken along the line II-II in Fig. 1. Fig. 3 shows a cross section including the through holes 31, 32, 33 and the first space s11. The first through hole 31 and the second through hole 32 penetrate the first mold part 2a along the Z direction. The first through hole 31 and the second through hole 32 are aligned in the Y direction. The first through hole 31 and the second through hole 32 are at the same position in the X direction. An opening 31a of the first through hole 31 on the Z2 direction side opens to the first inner surface 21. An opening 32a of the second through hole 32 on the Z2 direction side also opens to the first inner surface 21. The opening 31a is provided in the center in the Y direction of the first inner surface 21. The opening 32a is provided on the first inner surface 21 on the Y1 direction side of the opening 31a.

[0033] The third through hole 33 penetrates the second mold part 2b along the Z direction. An opening 33a of the third through hole 33 on the Z1 direction side opens to the second inner surface 22. The first through hole 31 and the third through hole 33 have the same central axis along the Z direction. Therefore, the position of the opening 31a and the position of the opening 33a on the XY plane coincide with each other.

[0034] The temperature sensor 10 provided in the second through hole 32 is, for example, a rod-shaped sheathed thermocouple. The temperature sensor 10 is inserted into the second through hole 32. The tip of the temperature sensor 10 is in contact with the lid 43. The lid 43 is a disk-shaped member provided in the second through hole 32. The lid 43 is formed from the same material as the mold 2 or a material with higher thermal conductivity than aluminum alloy, etc. The lid 43 covers the opening 32a of the through hole 32. The lid 43 is heated by the resin in the mold 2 and the molding space s1. The temperature sensor 10 measures the temperature of the heated lid 43. The temperature sensor 10 is connected to a measuring device or the like installed outside the mold 2. The temperature sensor 10 emits a signal, such as a voltage or resistance value, indicating the temperature of the lid 43. The signal indicating the temperature is converted into a temperature by the measuring device. The temperature of the lid 43 indicates the temperature near the molding space s1 of the mold 2. Therefore, the temperature sensor 10 can measure the temperature in the vicinity of the molding space s1 of the mold 2.

[0035] As shown in FIG. 3, the light projecting unit 4 (first light projecting unit) provided in the first through-hole 31 has a first optical fiber 51 and a window cover 41. The window cover 41 is a disk-shaped member provided inside the first through-hole 31. The window cover 41 is made of a material that is transmissive to infrared light. An example of a material that is transmissive to infrared light is sapphire glass. The window cover 41 closes the opening 31a of the through-hole 31. The first optical fiber 51 is inserted into the first through hole 31. A first end 51a of the first optical fiber 51 is connected to the window cover 41. The first end 51a is one of both end portions of the first optical fiber 51 that is located inside the first through hole 31. The second end 51b of the first optical fiber 51 is connected to the infrared light source 70. The second end 51b is the end opposite to the first end 51a.

[0036] The first optical fiber 51 guides the infrared light emitted from the infrared light source 70 to the window cover 41. The infrared light guided to the window cover 41 is projected toward the molding space s1 from the light-projecting surface 41a of the window cover 41. The light-projecting surface 41a is the surface exposed to the molding space s1 and extends along the first inner surface 21.

[0037] As shown in FIG. 3, the light receiving section 6 (first light receiving section) provided in the third through hole 33 has a second optical fiber 52 and a window cover . The window cover 42 is a disk-shaped member provided inside the third through-hole 33. The window cover 42 is made of a material that is transmissive to infrared light. An example of a material that is transmissive to infrared light is sapphire glass. The window cover 42 closes the opening 33a of the through-hole 33. The second optical fiber 52 is inserted into the third through hole 33. A first end 52a of the second optical fiber 52 is connected to the window cover 42. The first end 52a is one of both ends of the second optical fiber 52 that is located inside the third through hole 33. A second end 52b of the second optical fiber 52 is connected to the measurement unit 8. The second end 52b is the end opposite to the first end 52a. The measurement unit 8 is located outside the mold 2. The light receiving section 6 receives light through a light receiving surface 42a of the window cover 42. The light receiving surface 42a is a surface exposed to the molding space s1 and extends along the second inner surface 22.

[0038] The infrared light projected from the light projecting unit 4 and the infrared light radiated by the resin supplied into the molding space s1 are received by the light receiving surface 42a. In this embodiment, the position of the light-projecting surface 41a on the XY plane coincides with the position of the light-receiving surface 42a. Therefore, the infrared light from the light-projecting surface 41a is projected toward the light-receiving surface 42a. Therefore, the light-receiving surface 42a can efficiently receive the infrared light from the light-projecting surface 41a.

[0039] The relative positions of the light-emitting surface 41a and the light-receiving surface 42a may be slightly misaligned. FIG. 4A is a diagram for explaining the range in which the light receiving surface 42a is located relative to the light projecting surface 41a. 4A, center line C is a straight line that is perpendicular to center point 41a1 on the XY plane of light projection surface 41a. The pair of straight lines L extending from the center point 41a1 are the equilateral sides of an isosceles triangle centered on the center line C in a cross section including the center line C. The pair of straight lines L extending from the center point 41a1 are the generatrix of a cone centered on the center line C. The pair of intersection points P are points where the pair of straight lines L and the second inner surface 22 intersect. At least a portion of the light receiving surface 42a is located within a range E between the pair of intersection points P. At least a portion of the light receiving surface 42a overlaps the base of the cone. In this case, the apex angle θ of the isosceles triangle may be 45 degrees or less. If the apex angle θ is greater than 45 degrees, when the light-projecting surface 41a and the light-receiving surface 42a are offset by the maximum distance, the light-receiving surface 42a may have difficulty receiving transmitted light. If the apex angle θ is 45 degrees or less, the light-receiving surface 42a can properly receive transmitted light even when the light-projecting surface 41a and the light-receiving surface 42a are offset by the maximum distance.

[0040] The apex angle θ may be 30 degrees or less, in which case the light-receiving surface 42a can more appropriately receive the transmitted light even if the light-projecting surface 41a and the light-receiving surface 42a are offset by the maximum distance. The apex angle θ is more preferably 15 degrees or less.

[0041] FIG. 4B is a diagram showing an example of the positional relationship between light projection surface 41a and light reception surface 42a on the XY plane. In this embodiment, the position of the light projection surface 41a on the XY plane coincides with the position of the light receiving surface 42a. The center line C of the first through hole 31 coincides with the center line C of the third through hole 33. On the other hand, in the modified example of Fig. 4B, the position of light-projecting surface 41a is shifted from the position of light-receiving surface 42a. Central axis C of first through hole 31 is shifted from central axis C of third through hole 33. In the modified example of Fig. 4B, light-projecting surface 41a and light-receiving surface 42a have an overlapping region T where they overlap each other. In this way, even if the position of the light-projecting surface 41a and the position of the light-receiving surface 42a are misaligned, as long as the light-projecting surface 41a and the light-receiving surface 42a have an overlapping area T, the light-projecting surface 41a and the light-receiving surface 42a will be approximately facing each other, and the light-receiving surface 42a will be able to properly receive transmitted light.

[0042] Returning to FIG. 3, the light received by the light receiving surface 42 a is guided to the measuring unit 8 by the second optical fiber 52 . The measurement unit 8 includes a connector 8a, a spectroscope 8b, and a radiation thermometer 8c. The connector 8 a is provided at the second end 52 b of the second optical fiber 52 . The connector 8a connects the second optical fiber 52 to either the spectrometer 8b or the radiation thermometer 8c. When the connector 8a connects the second optical fiber 52 and the spectroscope 8b, the light received by the light receiving unit 6 is provided to the spectroscope 8b. When the connector 8a connects the second optical fiber 52 and the radiation thermometer 8c, the light received by the light receiving unit 6 is provided to the radiation thermometer 8c.

[0043] The light-projecting units 4 (second light-projecting units) provided in the through holes 34 and 37 also have the same configuration as the light-projecting unit 4 in the through hole 31. The temperature sensors 10 provided in the through holes 35 and 38 also have the same configuration as the temperature sensor 10 in the through hole 32. The light-receiving units 6 (second light-receiving units) provided in the through holes 36 and 39 also have the same configuration as the light-receiving unit 6 in the through hole 33.

[0044] In this embodiment, a plurality of light sources 70 are connected to a plurality of light projecting units 4, but instead of this, a single light source 70 may be connected to a plurality of light projecting units 4. Furthermore, in this embodiment, a plurality of measuring units 8 are connected to a plurality of light receiving units 6, but instead of this, a single measuring unit 8 may be used for a plurality of light receiving units 6.

[0045] [Measuring method using mold device 1] The mold device 1 can measure the transmittance of the resin filled in the molding space s1 and the change in the temperature of the resin over time during the process of injection molding a molded product. First, the first mold part 2a and the second mold part 2b are closed, and a clamping force is applied between the first mold part 2a and the second mold part 2b. Next, the multiple light projecting units 4 start projecting infrared light into the molding space s1. Furthermore, the connector 8a of each of the multiple measuring units 8 is connected to the spectroscope 8b. Furthermore, the temperature sensor 10 starts measuring the temperature.

[0046] Next, the resin is supplied to the sprue s2. Furthermore, the resin is supplied to the molding space s1. When the resin is supplied into the molding space s1, the infrared light from the light-projecting unit 4 passes through the resin in the molding space s1 and reaches the light-receiving unit 6. For example, when resin is supplied into the first space s11 in Fig. 3, the resin exists between the light-projecting surface 41a and the light-receiving surface 42a. Therefore, infrared light from the light-projecting surface 41a passes through the resin in the molding space s1 and reaches the light-receiving surface 42a. Therefore, the light-receiving unit 6 can receive transmitted light that has passed through the resin. The transmitted light received by the light receiving unit 6 is given to the spectroscope 8 b of the measurement unit 8 . The spectrometer 8b separates the transmitted light, measures the intensity of the separated transmitted light, and calculates the transmittance of the resin for each wavelength. In this way, the transmitted light is used to calculate the transmittance of the resin portion through which the light has passed.

[0047] Similar to the light receiving portion 6 of the third through hole 33, the light receiving portion 6 of the sixth through hole 36 receives transmitted light that has passed through the resin supplied into the second space s12. Therefore, the transmittance of the resin in the second space s12 can also be determined by the light receiving portion 6 of the sixth through hole 36. Furthermore, the light receiving portion 6 of the ninth through hole 39 receives transmitted light that has passed through the resin supplied into the third space s13. Therefore, the transmittance of the resin in the third space s13 can also be determined by the light receiving portion 6 of the ninth through hole 39.

[0048] FIG. 5 is a graph showing an example of the results of determining transmittance by spectrally separating transmitted light. 5, the horizontal axis represents wave number (or wavelength), and the vertical axis represents transmittance. In Fig. 5, graph g1 shows the transmittance of transmitted light in the first space s11, graph g2 shows the transmittance of transmitted light in the second space s12, and graph g3 shows the transmittance of transmitted light in the third space s13.

[0049] Graphs g1, g2, and g3 in Figure 5 show that the transmittance drops to almost 0 in a specific wavenumber band. The bands where the transmittance is almost 0 are absorption bands determined by the resin material. Therefore, the wavenumber for evaluation when determining the transmittance is determined in advance from among wavenumbers outside the absorption band, and the transmittance of transmitted light in each of the spaces s11, s12, and s13 is determined using the transmittance at the wavenumber for evaluation.

[0050] Once the transmittance of the transmitted light in each of the spaces s11, s12, and s13 has been determined, the projection of the infrared light by the light projecting unit 4 is stopped. Furthermore, the connector 8a of each of the plurality of measuring units 8 is connected to a radiation thermometer 8c. At this time, the light receiving section 6 receives the radiant light (infrared light) emitted from the resin. The radiation received by the light receiving unit 6 is given to the radiation thermometer 8c of the measuring unit 8. The radiation thermometer 8c determines the temperature of the resin based on the radiated light. In this way, the radiated light is used to determine the temperature of the resin portion through which the light has passed. The temperature of the resin in the first space s11 is determined based on the radiated light from the resin in the first space s11.

[0051] Similar to the light receiving portion 6 of the third through hole 33, the light receiving portion 6 of the sixth through hole 36 receives the light radiated from the resin in the second space s12. Therefore, the temperature of the resin in the second space s12 can be determined based on the light radiated from the resin in the second space s12. Furthermore, the light receiving portion 6 of the ninth through hole 39 receives the light radiated from the resin in the third space s13. Therefore, the temperature of the resin in the third space s13 can be determined based on the light radiated from the resin in the third space s13.

[0052] FIG. 6 is a graph showing the change in temperature of the resin over time as measured based on synchrotron radiation. In Fig. 6, the horizontal axis represents time, and the vertical axis represents temperature. In FIG. 6, graph g11 is shown by a solid line. Graph g11 shows the change in temperature of the resin in the first space s11 over time. In FIG. 6, graph g12 is shown by a dashed line. Graph g12 shows the change in temperature of the resin in the second space s12 over time. In FIG. 6, graph g13 is shown by a dashed line. In FIG. 6, graph g13 shows the change in temperature of the resin in the third space s13 over time. In FIG. 6, graph g15 is shown by a dashed line. The temperature peaks of the graphs g11, g12, and g13 are shifted depending on the order in which the resin reaches each of the spaces s11, s12, and s13. In FIG. 6, graph g15 represents the temperature of the temperature sensor 10, that is, the temperature of the mold 2. By measuring the radiation from the light receiving portion 6 of the third through hole 33, the light receiving portion 6 of the sixth through hole, and the light receiving portion 6 of the ninth through hole 39 using a radiation thermometer 8c, data is obtained that represents the change in the temperature of the resin over time in each of the spaces s11, s12, and s13.

[0053] According to the above configuration, during injection molding, light projected from the multiple light projecting units 4 passes through the resin in the molding space s1 and reaches the multiple light receiving units 6. Therefore, the multiple light receiving units 6 can receive transmitted light that has passed through the resin. The transmitted light is used to determine the transmittance of the resin portion through which the light has passed. Furthermore, if the projection of infrared light from the plurality of light projecting units 4 is stopped, the plurality of light receiving units 6 can receive radiant light emitted from the resin. The radiant light is used to determine the temperature of the resin portion. Therefore, each of the multiple measuring units 8 can obtain measured values ​​of both transmittance and temperature from approximately the same portion of the resin. As a result, it is possible to obtain the change in resin temperature over time when molding a resin with a specific transmittance, and it is possible to easily measure the transmittance of the resin and the change in temperature over time of the resin with that transmittance.

[0054] Furthermore, in this embodiment, the thicknesses in the Z direction of the spaces s11, s12, and s13 of the molding space s1 of the mold 2 are different from one another. Therefore, data showing the relationship between the transmittance of the resin during molding, the thickness of the resin, and changes in the resin temperature over time can be obtained. Therefore, by accumulating more of this data, it becomes possible to estimate how the resin temperature changes over time in the thickness direction (depth direction) of the resin from the relationship between the transmittance of the resin during molding and the thickness of the resin.

[0055] Furthermore, the measuring unit 8 of this embodiment includes a spectrometer 8b that disperses the light received by the light receiving unit 6 and measures the intensity of the dispersed transmitted light, a radiation thermometer 8c that measures the temperature based on the light received by the light receiving unit 6, and a connector 8a as a switching unit that guides the light received by the light receiving unit 6 to either the spectrometer 8b or the radiation thermometer 8c. In this case, the single light receiving section 6 can receive and measure the transmitted light and the emitted light. Instead of the connector 8a, an optical path switch may be provided at the second end 52b. In this case, the connection destination of the second optical fiber 52 can be switched by the optical path switch.

[0056] Furthermore, in this embodiment, one light receiving unit 6 is provided for one space, but instead of this, two light receiving units 6 may be provided for one space. In this alternative configuration, the spectrometer 8b can be connected to one of the two light receiving units 6, and the radiation thermometer 8c can be connected to the other. This eliminates the need to switch between the spectrometer 8b and the radiation thermometer 8c.

[0057] Furthermore, in this embodiment, the molding space s1 has three spaces s11, s12, and s13 of different thicknesses, and a light-projecting unit 4 and a light-receiving unit 6 are provided in each of the three spaces s11, s12, and s13, so that the temperature changes over time of multiple resin parts having different states can be measured in a single molding.

[0058] More specifically, the Z-direction distance between the first inner surface 21 and the second inner surface 22 of the first space s11, the Z-direction distance between the third inner surface 23 and the fourth inner surface 24 of the second space s12, and the Z-direction distance between the fifth inner surface 25 and the sixth inner surface 26 of the third space s13 are different from each other. In this case, the transmittance of each light receiving portion 6 is different from one another. Therefore, by using the mold device 1 of this embodiment, the change over time in temperature of multiple resin portions having different transmittances can be measured in a single molding operation.

[0059] In this embodiment, the temperature changes over time of three resin parts corresponding to the three spaces s11, s12, and s13 are measured in one molding run. Furthermore, if more similar spaces are provided, the temperature changes over time of more resin parts can be measured in one molding run.

[0060] [Regarding other embodiments] FIG. 7 is a cross-sectional view of the mold 2 of the mold apparatus 1 according to the second embodiment. This embodiment differs from the first embodiment in that the first through hole 31 and the third through hole 33 are formed along the Y direction, and the light-emitting section 4 and the light-receiving section 6 are provided in the second mold section 2b along the Y direction.

[0061] The first through hole 31 and the third through hole 33 are connected to the center of the molding space s1 in the Z direction. The first through-hole 31 and the third through-hole 33 have the same central axis along the Y direction. Therefore, the position of the light projection surface 41a on the XZ plane coincides with the position of the light receiving surface 42a. In this configuration, the transmittance and the change in temperature of the resin having that transmittance over time can also be easily measured.

[0062] FIG. 8A is a cross-sectional view of the mold 2 of the mold apparatus 1 according to the third embodiment. This embodiment differs from the second embodiment in that a parting line D along which the first mold portion 2a and the second mold portion 2b are joined together is positioned at the center of the molding space s1 in the Z direction. In this embodiment, the first through-hole 31 and the third through-hole 33 are provided along the parting line D. In this configuration, the transmittance and the change in temperature of the resin having that transmittance over time can also be easily measured.

[0063] FIG. 8B is a cross-sectional view of the mold 2 of the mold apparatus 1 according to a modified example of the third embodiment. This modified example differs from the third embodiment in that the first through-hole 31 is provided in the first mold portion 2a, and the third through-hole 33 is provided in the second mold portion 2b.

[0064] In this modified example, the position of the light projection surface 41a and the position of the light receiving surface 42a are shifted in the XZ plane. However, as shown in this modified example, if at least a portion of the light receiving surface 42a is located in the range E shown in FIG. 4A and the apex angle θ in FIG. 4A is 45 degrees or less, the light receiving surface 42a can properly receive transmitted light.

[0065] 〔others〕 The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is not limited to the above-described embodiments, but includes all modifications within the scope of equivalents to the configurations described in the claims. [Explanation of symbols]

[0066] 1. Mold equipment 2. Mold 4 Light-emitting unit (first light-emitting unit) 6 Light receiving section (1st light receiving section) 8. Measurement section 8a Connector (switching part) 8b spectrometer 8c radiation thermometer 21 First inner surface 22 Second inner surface 23 Third Inner Surface 24 Fourth Inner Surface 25 5th Inner Surface 26 Sixth Inner Surface 31 First through hole 32 Second through hole 33 Third through hole 34 4th through hole 41a Light projection surface 42a Photosensitive surface 51 First Optical Fiber 52 Second optical fiber

Claims

1. a mold having a molding space into which resin is injected; a first light projecting unit that is provided on a first inner surface of the molding space and projects infrared light toward the molding space; a first light receiving portion provided on a second inner surface facing the first inner surface in the molding space; a measuring unit that measures the light received by the first light receiving unit, Mold equipment.

2. the first light-projecting unit has a light-projecting surface exposed to the first inner surface, the first light receiving portion has a light receiving surface exposed to the second inner surface, in a cross section of the first inner surface including a center line perpendicular to the center point of the light-projecting surface, at least a part of the light-receiving surface is located between a pair of intersection points where a pair of equal sides of an isosceles triangle having the center point as an apex and the center line as a center intersect with the second inner surface, The apex angle of the isosceles triangle is 45 degrees or less. The mold apparatus according to claim 1 .

3. The apex angle of the isosceles triangle is 30 degrees or less. The mold apparatus according to claim 2 .

4. The apex angle of the isosceles triangle is 15 degrees or less. The mold apparatus according to claim 3 .

5. the first light-projecting unit has a light-projecting surface exposed to the first inner surface, the first light receiving portion has a light receiving surface exposed to the second inner surface, The light-projecting surface and the light-receiving surface have an overlapping region in which they overlap each other when the first inner surface is viewed from above. The mold apparatus according to claim 1 .

6. The measurement unit a spectroscope that separates the light received by the first light receiving unit; a radiation thermometer that measures a temperature based on the light received by the first light receiving unit; a switching unit that guides the light received by the first light receiving unit to either the spectroscope or the radiation thermometer. The mold apparatus according to claim 1 .

7. The mold is a first through hole communicating the first inner surface with the outside of the mold; a second through hole communicating the second inner surface with the outside of the mold; the first light projecting unit has a first optical fiber that is inserted into the first through hole and guides infrared light emitted from a light source outside the mold to the first inner surface, The first light receiving unit a light receiving surface exposed to the second inner surface; a second optical fiber that is inserted into the second through hole and that guides the light received on the light receiving surface to the measurement unit; The mold apparatus according to claim 1 .

8. a second light projecting unit provided on a third inner surface of the molding space and projecting infrared light toward the molding space; a second light receiving portion provided on a fourth inner surface facing the third inner surface in the molding space. The mold apparatus according to claim 1 .

9. The distance between the first inner surface and the second inner surface is different from the distance between the third inner surface and the fourth inner surface. The mold apparatus according to claim 8.

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