Molding device and molding method

Abstract

To provide a molding device of a vibrator.SOLUTION: A molding device includes a flat upper surface, and a molding tool having a hole formed on a part of the upper surface. The molding device includes a ring member arranged on the upper surface, and surrounds the perimeter of the hole. The molding device includes heating means arranged over the hole. The molding device includes a thermometer arranged over the ring member, and capable of measuring a temperature of the ring member in the noncontact way.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present specification relates to an apparatus and method for forming a vibrator. [Background technology]

[0002] Patent Document 1 discloses a Bird-bath Resonator Gyroscope (BRG) that uses fused silica as an oscillator as a gyroscope that can achieve high accuracy. Specifically, a quartz plate is placed on a mold such as graphite, and while reducing the pressure on the bottom surface of the quartz plate, the top surface of the quartz plate is heated with a burner to melt and deform the plate, creating a hemispherical oscillator. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2018 / 079129 Summary of the Invention [Problem to be solved by the invention]

[0004] This process control requires that temperature information of the quartz plate be obtained without contact, but this is difficult to do because the quartz plate deforms quickly and is thin (e.g., 100 μm). [Means for solving the problem]

[0005] One embodiment of the molding apparatus disclosed herein includes a mold having a flat upper surface and a hole formed in a portion of the upper surface. The molding apparatus includes a ring member disposed on the upper surface and surrounding the outer periphery of the hole. The molding apparatus includes a heating means disposed above the hole. The molding apparatus includes a thermometer disposed above the ring member and capable of measuring the temperature of the ring member without contact.

[0006] The ring member does not deform during molding. In addition, the ring member can be made thicker than the material to be processed. Therefore, the temperature of the ring member can be measured without contact using a thermometer. Since the temperature information corresponding to the material to be processed can be accurately detected, process control becomes possible.

[0007] The ring member may be disposed on the upper surface via a plate-shaped workpiece disposed on the upper surface.

[0008] The ring member may have a first portion extending outward from the outer periphery of the ring member. The lower surface of the first portion may be located lower than the lower surface of the ring member and parallel to the lower surface of the ring member. The lower surface of the ring member may be configured to be able to contact the surface of the workpiece. The lower surface of the first portion may be configured to be able to contact the upper surface. Details of the effects will be described in the examples.

[0009] The first portion may include a fixing portion capable of fixing the first portion to the upper surface. Details of the effects will be described in the examples.

[0010] The ring member may be disposed so as to contact the upper surface. Details of the effects will be described in the examples.

[0011] The surface of the ring member may be parallel to the upper surface and located above the upper surface. Details of the effects will be described in the examples.

[0012] The back surface of the ring member may have a surface roughness smaller than that of the front surface of the ring member. Details of the effect will be described in the examples.

[0013] The melting point of the ring member may be 1000° C. or higher.

[0014] The width of the ring member may be equal to or greater than the measurement spot diameter of the thermometer.

[0015] One embodiment of a molding method disclosed in this specification includes a placement step of placing a plate-shaped workpiece material on the upper surface of a mold having an upper surface in which a hole is formed, so as to cover the hole. The molding method includes a heating step of heating the upper surface of the workpiece material with a heating means to melt and deform it while reducing the pressure inside the hole. The molding method includes a measurement step of measuring a predetermined temperature corresponding to the temperature of the workpiece material using a non-contact thermometer. The molding method includes a step of controlling the heating means based on the predetermined temperature. Details of the effects will be described in the examples.

[0016] The molding method may further include a step of arranging a ring member surrounding the outer periphery of the hole on the surface of the workpiece arranged on the upper surface by the arranging step. The measuring step may measure the temperature of the surface of the ring member. Details of the effects will be described in the examples.

[0017] A ring member surrounding the outer periphery of the hole may be disposed on the upper surface. In the disposing step, the workpiece may be disposed on the ring member. In the measuring step, the temperature of the surface of the ring member may be measured by measuring the wavelength transmitted through the workpiece. Details of the effects will be described in the examples.

[0018] A roughened surface region having a large surface roughness may be formed on a part of the surface of the workpiece. In the measuring step, the temperature of the roughened surface region may be measured. Details of the effect will be described in the examples.

[0019] In the measuring step, the temperature of the upper surface may be measured by measuring a wavelength transmitted through the material to be processed. [Brief description of the drawings]

[0020] [Figure 1] FIG. 2 is a top view of the molding apparatus 1 of the first embodiment. [Diagram 2] FIG. 1 is a cross-sectional view of a molding apparatus 1 of a first embodiment. [Diagram 3] FIG. 3 is a cross-sectional view after melt deformation. [Figure 4] FIG. 11 is a top view of a molding apparatus 201 according to a second embodiment. [Diagram 5]FIG. 11 is a cross-sectional view of a molding apparatus 201 according to a second embodiment. [Figure 6] FIG. 11 is a cross-sectional view of a molding apparatus 301 according to a third embodiment. [Figure 7] FIG. 11 is a cross-sectional view of a molding apparatus 401 according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLES

[0021] Figures 1 and 2 show a molding apparatus 1 of Example 1. Figure 1 is a top view. Figure 2 is a cross-sectional view taken along line II-II in Figure 1. The molding apparatus 1 includes a plate 10, a molding die 20, a quartz plate 30, a ring 40, a burner 50, and a thermometer 60. Note that the plate 10, the burner 50, and the thermometer 60 are omitted from Figure 1.

[0022] The plate 10 is a stainless steel base for placing the molding die 20. The plate 10 has an opening 10a. The opening 10a can be evacuated by a vacuum pump (not shown).

[0023] The molding die 20 is a die for molding a hemispherical transducer using fused silica. The transducer is a component of a Bird-bath Resonator Gyroscope (BRG). The molding die 20 is made of graphite. In this embodiment, the molding die 20 is a disk shape having a central axis CA. The molding die 20 has an upper surface 20s, a hole 20h, a support 20p, and an exhaust port 20e. The upper surface 20s is a flat surface perpendicular to the central axis CA. A hole 20h is formed in a part of the upper surface 20s. The hole 20h is a deformation space for the quartz plate 30 to melt and deform. In this embodiment, the hole 20h is formed in a cylindrical shape centered on the central axis CA. A support 20p extending vertically upward from the bottom surface 20b is arranged in the center of the hole 20h. The support 20p is a cylinder with the central axis CA as its central axis. The bottom surface 20b is formed with a plurality of exhaust ports 20e penetrating through to the rear surface 20r. The exhaust ports 20e are connected to the opening 10a.

[0024] A quartz plate 30 is disposed on the upper surface 20s so as to cover the hole 20h. The quartz plate 30 is a material to be processed for forming the vibrator. The thickness of the quartz plate 30 is, for example, 100 μm. In this embodiment, the quartz plate 30 is square, but may be rectangular or circular.

[0025] A ring 40 is disposed on the surface of the quartz plate 30 so as to surround the outer periphery of the hole 20h. In other words, the ring 40 is disposed on the upper surface 20s via the quartz plate 30. The ring 40 is circular, and its center coincides with the central axis CA. The inner diameter D1 of the ring 40 is larger than the diameter D2 of the hole 20h. The width W1 of the ring 40 is equal to or larger than the measurement spot diameter of the thermometer 60. The thickness T1 of the ring 40 is equal to or larger than the thickness T2 of the quartz plate 30.

[0026] The rear surface 40r of the ring 40 has a smaller surface roughness than the front surface 40s. By increasing the smoothness of the rear surface 40r, the thermal resistance of the contact interface with the quartz plate 30 can be reduced. Since the heat transfer from the quartz plate 30 to the ring 40 can be increased, the temperature of the ring 40 can be made closer to the temperature of the quartz plate 30. Furthermore, by worsening the surface roughness of the front surface 40s, the emissivity of far-infrared rays can be increased. The measurement accuracy of the thermometer 60 can be improved.

[0027] It is preferable that the width W1 and thickness T1 of the ring 40 are as small as possible within a range that can be measured by the thermometer 60. This makes it possible to suppress heat discharge and heat storage by the ring 40, thereby improving the accuracy of temperature measurement.

[0028] The burner 50 is a means for heating the quartz plate 30 by a flame. The burner 50 is movable up and down along the central axis CA. The thermometer 60 is a non-contact thermometer that uses far-infrared rays. The measurement spot of the thermometer 60 is located on the surface of the ring 40.

[0029] (Ring 40 Materials) The ring 40 is made of a material with a melting point of 1000°C or higher. The reason is explained below. The quartz plate 30 arranged in the hole 20h has a thermal conduction path only in the surface direction of the quartz plate. Therefore, in the heating process described below, it is heated to 1600°C or higher by the burner 50. On the other hand, the quartz plate 30 arranged on the upper surface 20s has a thermal conduction path to the molding die 20. Therefore, since heat is discharged during the heating process, the maximum temperature can be suppressed to a temperature lower than 1000°C (for example, about 700°C). Since the ring 40 is located on the surface of the quartz plate 30 arranged on the upper surface 20s, the maximum temperature of the ring 40 is also suppressed to a temperature lower than 1000°C. Therefore, by making the melting point of the ring 40 1000°C or higher, it is possible to prevent the ring 40 from melting.

[0030] The material of the ring 40 is preferably a material that is resistant to oxidation (e.g., gold). This can prevent cracks caused by oxidation due to flames. The material of the ring 40 is also preferably a material with high density. This can increase the mass of the ring 40, preventing the ring 40 from moving due to the flame pressure of the burner 50. The material of the ring 40 is also preferably resistant to thermal shock caused by burner heating and can be processed into a ring shape.

[0031] Specific examples of materials for the ring 40 include high melting point metals (e.g., gold, platinum, zirconia, etc.), various alloys, oxides, etc. Below is a list of materials that can be used for the ring 40. These materials may be used alone, may be mixed together, or may be used as a compound.

[0032] Examples of materials for ring 40: gold, platinum, zirconia, silver, aluminum nitride, silicon nitride, boron nitride, silicon carbide, alumina, germanium, cobalt, samarium, silicon, scandium, stainless steel, quartz glass, tungsten, tantalum, titanium, iron, copper, niobium, nickel, neodymium, manganese, and molybdenum.

[0033] The thermal conductivity of the ring 40 is preferably higher than that of the mold 20. This allows the ring 40 to be heated more uniformly than the mold 20. The ring 40 is in contact with the quartz plate 30 on the outer periphery of the hole 20h. Therefore, the ring 40 can function as a heat transfer material for uniformizing the temperature of the quartz plate 30 on the outer periphery of the hole 20h. It is possible to suppress variation in the processed shape of the vibrator.

[0034] (manufacturing process) The manufacturing process of the vibrator will be described with reference to Figures 2 and 3. In step S1, the mold 20 is placed on the plate 10. In step S2, the quartz plate 30 is placed on the upper surface 20s. In step S3, the opening 10a is evacuated to a desired vacuum level. The hole 20h is also evacuated via the exhaust port 20e. The quartz plate 30 is adsorbed and fixed to the upper surface 20s. In step S4, the ring 40 is placed on the surface of the quartz plate 30. This results in the state shown in Figure 2.

[0035] In step S5, a heating step is performed. Specifically, the burner 50 is ignited and lowered at a desired speed. In step S6, a measurement step is performed. The temperature of the ring 40 is measured using the thermometer 60.

[0036] In step S7, processing parameters are controlled based on the measured temperature value of the ring 40. Specifically, various processing parameters such as the gas flow rate of the burner 50, the distance between the burner 50 and the quartz plate 30, the reduced pressure, and the heating time are feedback-controlled based on the measured temperature value. This allows the quartz plate 30 to be melted and deformed into a desired shape, as shown in FIG.

[0037] In step S8, the burner 50 is raised and extinguished in response to detection of the processing end point based on the temperature measurement value. After the quartz plate 30 is cooled to the desired temperature, the hole 20h is opened to the atmosphere. The melt-processed quartz plate 30 is removed from the mold 20. In step S9, the unformed portion is removed by a CMP method or the like to complete the vibrator.

[0038] (effect) The problem will now be explained. In conventional techniques that do not use the ring 40, it is difficult to obtain temperature information of the quartz plate in a non-contact manner. This is due to the fact that the quartz plate deforms at high speed and is thin (e.g., 100 μm). Therefore, in the past, process control was performed by controlling processing parameters (e.g., burner gas flow rate, distance between the burner and the quartz plate, heating time, etc.) without using temperature information. The low accuracy of process control resulted in large variations in the processed shape of the vibrator, leading to a decrease in yield.

[0039] In the technology of this embodiment, the ring 40 is placed on the quartz plate 30. The ring 40 does not deform during molding. The thickness T1 of the ring 40 can be made thicker than the thickness T2 of the quartz plate 30. Therefore, the temperature of the ring 40 can be measured by the thermometer 60 in a non-contact manner. Since the temperature of the ring 40 follows the temperature change of the quartz plate 30 with high accuracy, it is possible to obtain temperature information corresponding to the temperature of the quartz plate 30 by measuring the temperature of the ring 40. Since the process can be controlled based on the temperature information of the quartz plate 30, it is possible to improve the accuracy of the process control. Since the variation in the processed shape of the vibrator can be suppressed, the yield is improved and the manufacturing cost can be reduced. Furthermore, by using the temperature information, it is possible to improve the accuracy of the thermal design of the molding die 20.

[0040] Since the ring 40 has a high thermal conductivity, the temperature in the circumferential direction can be made uniform. Therefore, by measuring the temperature at one point on the ring 40 with the thermometer 60, the average temperature of the entire ring 40 can be obtained. Since accurate temperature information can be obtained, it is possible to improve the accuracy of process management. Note that the temperatures of multiple points on the ring 40 may be measured. EXAMPLES

[0041] 4 and 5 show a top view and a cross-sectional view of a molding apparatus 201 of Example 2. Example 2 differs from Example 1 in that a ring 240 is provided with a flange 240f. The same reference numerals are used to designate parts common to the molding apparatus 1 of Example 1, and description thereof will be omitted.

[0042] The ring 240 includes a flange 240f extending outward from the outer periphery of the ring 240. A lower surface 240fr of the flange 240f is located lower than a lower surface 240r of the ring 240. The lower surface 240fr of the flange 240f is parallel to the lower surface 240r of the ring 240. The lower surface 240r of the ring 240 is configured to be able to come into contact with the surface of the quartz plate 30. The lower surface 240fr of the flange 240f is configured to be able to come into contact with the upper surface 20s of the molding die 20.

[0043] The screws 241 are passed through screw holes formed in the flange 240f and screwed into the upper surface 20s. The screws 241 allow the flange 240f to be fixed to the upper surface 20s.

[0044] (effect) The ring 240 can be fixed to the upper surface 20s by the screw 241. It is possible to prevent the ring 240 from moving due to the flame pressure. In addition, since the pressing pressure of the ring 240 can be increased, it is possible to improve the airtightness between the quartz plate 30 and the upper surface 20s. Since the pressure fluctuation can be suppressed when the hole 20h is decompressed, it is possible to suppress the variation in the processed shape of the vibrator.

[0045] (Modification of the second embodiment) The flange 240f does not have to include the screw 241. This also makes it possible for the flange 240f to restrict movement of the quartz plate 30 in the planar direction. EXAMPLES

[0046] 6 shows a cross-sectional view of a molding apparatus 301 of Example 3. Example 3 differs from Example 1 in that a ring 40 is disposed between the upper surface 20s and the quartz plate 30. The same reference numerals are used to designate parts common to the molding apparatus 1 of Example 1, and description thereof will be omitted.

[0047] The ring 40 is disposed so as to be in contact with the upper surface 20s of the molding die 20. The surface 40s of the ring 40 is parallel to the upper surface 20s and is located above the upper surface 20s. The quartz plate 30 is disposed on the surface 40s of the ring 40.

[0048] The thermometer 60 measures the wavelength transmitted through the quartz plate 30. Specifically, quartz glass is transparent at wavelengths of approximately 3 μm or less. Therefore, for example, near-infrared rays (wavelengths of approximately 0.78 μm to 1.5 μm) are measured. This makes it possible to measure the temperature of the ring 40.

[0049] (effect) The problem will be explained. In order to increase the sensitivity of the gyro sensor, the inclination angle θ (see FIG. 3) of the rim of the vibrator needs to be close to 90°. However, since the rim portion is difficult to deform, the inclination angle θ becomes smaller than 90°. This is because the heat of the quartz plate 30 heated by the burner 50 is discharged to the mold 20 through the contact surface between the quartz plate 30 and the upper surface 20s of the mold 20. As a result, the quartz plate 30 has a temperature gradient in which the temperature decreases toward the outer periphery of the hole 20h, so the rim portion is difficult to deform. In this embodiment, the ring 40 allows the quartz plate 30 to be structured so that it floats upward from the upper surface 20s. Since the contact area between the quartz plate 30 and the upper surface 20s can be reduced, the amount of heat discharged from the quartz plate 30 to the mold 20 can be reduced. Since the temperature drop at the outer periphery of the hole 20h can be suppressed, it is possible to make the inclination angle θ of the rim close to 90°.

[0050] (Modification of the third embodiment) The ring 40 may not be provided, and the quartz plate 30 may be in contact with the upper surface 20s. The thermometer 60 may measure a wavelength (e.g., near-infrared rays) that passes through the quartz plate 30. This makes it possible to obtain temperature information corresponding to the temperature of the quartz plate 30 by measuring the temperature of the upper surface 20s located below the quartz plate 30. EXAMPLES

[0051] 7 shows a cross-sectional view of a molding apparatus 401 of Example 4. Example 4 differs from Example 1 in that it does not include a ring 40. The same reference numerals are used to designate parts common to the molding apparatus 1 of Example 1, and description thereof will be omitted.

[0052] The quartz plate 30 has a processing region R1 that is processed into an oscillator, and a peripheral region R2 that is not processed into an oscillator. The surface of the processing region R1 is a smooth surface on the order of nanometers. A rough surface region is formed on at least a part of the surface of the peripheral region R2. The rough surface region is a region whose surface roughness is larger than that of the processing region R1. The measurement spot of the thermometer 60 is located in the rough surface region.

[0053] (effect) The quartz plate 30, which has a flatness on the nanometer order, reflects far-infrared rays, so the temperature of the quartz plate 30 itself cannot be measured by the thermometer 60. In this embodiment, a rough surface area is formed in the peripheral area R2, and the temperature of the rough surface area is measured by the thermometer 60. Since the rough surface area does not reflect far-infrared rays, it is possible to measure the temperature using the thermometer 60. It becomes possible to perform non-contact temperature measurement of the quartz plate 30 without using the ring 40. Furthermore, since the peripheral area R2 is an area that will be removed after processing (see step S9), there is no problem even if a rough surface area is formed.

[0054] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples exemplified above.

[0055] (Modification) The material of the vibrator is not limited to the quartz plate 30. Any dielectric material that melts and deforms may be used. The material of the mold 20 is not limited to graphite.

[0056] The diameter D2 and depth of the holes 20h may vary, and the height and diameter of the posts 20p may vary.

[0057] In addition, the technical elements described in this specification or drawings exert technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technologies exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of those objectives is itself technically useful.

[0058] The burner 50 is an example of a heating means. The quartz plate 30 is an example of a material to be processed. The flange 240f is an example of a first portion. The screw 241 is an example of a fixing portion. [Explanation of symbols]

[0059] 1, 201, 301, 401: molding device 20: molding die 20e: exhaust port 20h: hole 20p: support 20s: upper surface 30: quartz plate 40: ring 50: burner 60: thermometer

Claims

1. a mold having a flat upper surface and a hole formed in a portion of the upper surface; A ring member disposed on the upper surface and surrounding an outer periphery of the hole; A heating means disposed above the hole; a thermometer disposed above the ring member and capable of measuring a temperature of the ring member in a non-contact manner; A molding apparatus comprising:

2. The molding apparatus according to claim 1 , wherein the ring member is disposed on the upper surface via a plate-shaped workpiece that is disposed on the upper surface.

3. the ring member includes a first portion extending outwardly from an outer periphery of the ring member; a lower surface of the first portion is located lower than a lower surface of the ring member and is parallel to the lower surface of the ring member; The lower surface of the ring member is configured to be able to contact the surface of the workpiece, The molding apparatus according to claim 2 , wherein a lower surface of the first portion is configured to be able to contact the upper surface.

4. The first portion includes a fixing portion capable of fixing the first portion to the upper surface. The molding apparatus according to claim 3.

5. The molding apparatus of claim 1 , wherein the ring member is positioned to contact the upper surface.

6. The molding apparatus according to claim 5 , wherein a surface of the ring member is parallel to the upper surface and is located above the upper surface.

7. The molding apparatus according to any one of claims 1 to 6, wherein the rear surface of the ring member has a surface roughness smaller than that of the front surface of the ring member.

8. The molding apparatus according to any one of claims 1 to 7, wherein the ring member has a melting point of 1000°C or higher.

9. The molding apparatus according to any one of claims 1 to 8, wherein the width of the ring member is equal to or larger than a measurement spot diameter of the thermometer.

10. a placement step of placing a plate-shaped workpiece on an upper surface of a mold having an upper surface in which a hole is formed, so as to cover the hole; a step of placing a ring member surrounding an outer periphery of the hole on a surface of the workpiece placed on the upper surface by the placing step; a heating step of heating an upper surface of the workpiece with a heating means to melt and deform the upper surface while reducing the pressure inside the hole; a measuring step of measuring a predetermined temperature corresponding to the temperature of the workpiece using a non-contact thermometer; controlling the heating means based on the predetermined temperature; Equipped with In the measuring step, a temperature of a surface of the ring member is measured. Molding method.

11. a placement step of placing a plate-shaped workpiece on an upper surface of a mold having an upper surface in which a hole is formed, so as to cover the hole; a heating step of heating an upper surface of the workpiece with a heating means to melt and deform the upper surface while reducing the pressure inside the hole; a measuring step of measuring a predetermined temperature corresponding to the temperature of the workpiece using a non-contact thermometer; controlling the heating means based on the predetermined temperature; Equipped with A ring member is disposed on the upper surface so as to surround an outer periphery of the hole, In the placing step, the workpiece is placed on the ring member; In the measuring step, a wavelength transmitted through the workpiece is measured to measure a temperature of the surface of the ring member. Molding method.

12. a placement step of placing a plate-shaped workpiece on an upper surface of a mold having an upper surface in which a hole is formed, so as to cover the hole; a heating step of heating an upper surface of the workpiece with a heating means to melt and deform the upper surface while reducing the pressure inside the hole; a measuring step of measuring a predetermined temperature corresponding to the temperature of the workpiece using a non-contact thermometer; controlling the heating means based on the predetermined temperature; Equipped with A rough surface region having a large surface roughness is formed on a part of the surface of the workpiece, In the measuring step, the temperature of the rough surface region is measured. Molding method.

13. a placement step of placing a plate-shaped workpiece on an upper surface of a mold having an upper surface in which a hole is formed, so as to cover the hole; a heating step of heating an upper surface of the workpiece with a heating means to melt and deform the upper surface while reducing the pressure inside the hole; a measuring step of measuring a predetermined temperature corresponding to the temperature of the workpiece using a non-contact thermometer; controlling the heating means based on the predetermined temperature; Equipped with In the measuring step, a wavelength transmitted through the workpiece is measured to measure a temperature of the upper surface. Molding method.

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