Manufacturing method of base body of coil component

Abstract

To appropriately process the surface of a compact even when an electronic component is miniaturized.SOLUTION: A method of manufacturing a substrate of a coil component includes the steps of: forming a molded body 10 obtained by performing pressure-molding on a mixture containing inorganic powder and a resin; and placing a part to be worked (the inner surface of a groove part 16) which is a part of the molded body 10 on a processing part 32 of a processing device 30 so as to be brought into contact therewith and processing the part to be worked which is a part of the molded body 10 by repeatedly moving the molded body 10 obliquely downward and obliquely upward in the vertical direction different form the conveying direction while moving the molded body 10 to the conveying direction in which the processing part 32 extends; and performing heat treatment on the molded body 10.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a base body of a coil component. [Background technology]

[0002] Substrates used for coil parts and the like are obtained by forming a molded body by pressure molding a mixture containing inorganic powder and resin, and then heat treating the molded body. Methods have been proposed for removing burrs that are generated when forming the molded body (e.g., Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2015-194353 [Patent Document 2] JP 2017-108029 A Summary of the Invention [Problem to be solved by the invention]

[0004] It is common to process the surface of a molded body by barrel polishing after forming the molded body. However, as electronic components become smaller, the media used in barrel polishing become smaller, so the weight of the media becomes lighter and the kinetic energy becomes smaller, making it difficult to properly process the surface of the molded body. In addition, the methods described in Patent Documents 1 and 2 mainly process the surface of the molded body by frictional energy, which requires a long processing time, and there is room for improvement.

[0005] The present invention has been made in consideration of the above problems, and has an object to make it possible to appropriately process the surface of a molded body even when electronic components are miniaturized. [Means for solving the problem]

[0006] The present invention relates to a process for forming a molded body by pressure molding a mixture containing an inorganic powder and a resin, and a processing unit of a processing device. The rail section A part to be processed, which is a part of the molded body, is placed on the molded body so that the part to be processed is in contact with the molded body. The rail portion The method for manufacturing the base of a coil component includes a step of processing the processed portion, which is a part of the molded body, by moving the molded body in a conveying direction in which a coil spring extends while repeatedly moving the molded body diagonally downward and upward in a direction different from the conveying direction; and a step of heat-treating the molded body.

[0007] In the above configuration, The rail portion extends in the conveying direction while repeating valleys and peaks. R It can be configured as follows.

[0008] In the above configuration, the rail portion may extend in the conveying direction while bending in the left-right direction when viewed from above.

[0009] In the above configuration, the processed portion which is a part of the molded body may be a concave portion when the molded body is viewed in cross section on a plane perpendicular to the conveying direction.

[0010] In the above configuration, The rail portion The width of the upper portion in a direction perpendicular to the transport direction may be smaller than the width between the inner surfaces of the recessed portion when viewed in cross section along a plane perpendicular to the transport direction.

[0011] In the above configuration, the molded body can be configured to include a shaft portion around which the coil conductor is wound, and a flange portion provided at the end of the shaft portion and having the concave portion through which the coil conductor is pulled out.

[0012] In the above configuration, the processed portion which is a part of the molded body may be a ridge portion of the molded body.

[0013] In the above configuration, The rail portion The width of the upper portion in a direction perpendicular to the transport direction may vary in the transport direction.

[0014] In the above configuration, the processing device is The rail portion and in a direction perpendicular to the conveying direction The rail portion and face each other across a gap, The rail portion and a holding portion for holding the The rail portion The molded body may be moved in the transport direction by vibrating the molded body.

[0015] In the above configuration, the processing device is The rail portion and a conveying unit, the conveying unit is vibrated to move the molded body in the conveying direction, The rail portion The machined portion, which is a part of the molded body, can be machined by vibrating the machined portion. Effect of the Invention

[0016] According to the present invention, the surface of the molded body can be appropriately processed. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a flowchart showing an example of a method for manufacturing a substrate according to the first embodiment. [Diagram 2] FIG. 2(a) is a plan view showing an example of a molded body, and FIG. 2(b) is a side view seen from a direction A in FIG. 2(a). [Diagram 3] Figure 3(a) is a top view showing the processing of the molded body in the first embodiment, Figure 3(b) is a side view seen from direction A in Figure 3(a), and Figure 3(c) is a side view seen from direction B in Figure 3(b). [Figure 4] 4(a) and 4(b) are side views illustrating the processing by the processing unit. [Diagram 5] FIG. 5(a) is a top view of a processing apparatus of a first modified example according to the first embodiment, FIG. 5(b) is a side view seen from direction A in FIG. 5(a), and FIG. 5(c) is a side view seen from direction B in FIG. 5(b). [Figure 6]FIG. 6(a) is a top view of a processing apparatus of a second modified example according to the first embodiment, FIG. 6(b) is a side view seen from direction A in FIG. 6(a), and FIG. 6(c) is a side view seen from direction B in FIG. 5(b). [Figure 7] FIG. 7(a) is a top view of a processing apparatus of a third modified example according to the first embodiment, FIG. 7(b) is a side view seen from direction A in FIG. 7(a), and FIG. 7(c) is a side view seen from direction B in FIG. 7(b). [Figure 8] FIG. 8(a) is a top view of a processing apparatus of a fourth modified example according to the first embodiment, and FIG. 8(b) is a side view seen from a direction A in FIG. 8(a). [Figure 9] 9(a) and 9(b) are top views showing other examples of bending of the processing unit of the processing device of the fourth modified example according to the first embodiment. [Figure 10] Figure 10(a) is a top view showing the processing of a molded body in the second embodiment, Figure 10(b) is a side view seen from direction A in Figure 10(a), and Figure 10(c) is a side view seen from direction B in Figure 10(b). [Figure 11] FIG. 11(a) is a top view of a processing apparatus of a first modified example according to the second embodiment, and FIG. 11(b) is a side view seen from a direction A in FIG. 11(a). [Figure 12] 12(a) and 12(b) are views of the molded body according to the third embodiment before surface processing, and FIGS. 12(c) and 12(d) are views of the molded body after surface processing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings as appropriate. However, the present invention is not limited to the illustrated embodiment. In addition, components common to multiple drawings are given the same reference numerals throughout the multiple drawings. Please note that the drawings are not necessarily drawn to scale for the sake of convenience.

[0019] [First embodiment] Fig. 1 is a flow chart showing an example of a method for manufacturing a substrate according to the first embodiment. As shown in Fig. 1, first, a mixture containing an inorganic powder and a resin is pressure-molded to form a molded body (step S10). For example, a magnetic paste, which is a mixture of a magnetic powder and a resin, is filled into a cavity of a mold and press-molded to form a molded body. As the magnetic powder, a ferrite powder or a metal magnetic powder is used. Note that a non-magnetic powder such as a dielectric powder or a glass powder may be used instead of the magnetic powder.

[0020] FIG. 2(a) is a plan view showing an example of the molded body 10, FIG. 2(b) is a side view seen from the A direction of FIG. 2(a), and FIG. 2(c) is a side view seen from the B direction of FIG. 2(a). As shown in FIG. 2(a) to FIG. 2(c), the molded body 10 is, for example, a drum core including a shaft portion 12 and flange portions 14a and 14b provided at both ends of the shaft portion 12. On the surface of the flange portion 14a opposite to the surface to which the shaft portion 12 is connected, two groove portions 16 are provided from which the coil conductor wound around the shaft portion 12 is drawn out. The width W of the groove portion 16 is, for example, 0.5 mm or less. The groove portion 16 is composed of at least three flat surfaces, and the angle between the adjacent surfaces is 90° or more. The groove portion 16 may have a shape in which the front side is wider than the back side.

[0021] In the molded body 10, burrs 18 may occur on the inner surface 17 of the groove portion 16. The burrs 18 are formed when part of the inorganic powder gets into gaps in the die during pressure molding to form the molded body 10. The size of the burrs 18 varies depending on the size of the inorganic powder, the size of the die clearance, and / or the pressure during pressure molding. When the size of the die clearance is larger than the size of the inorganic powder, large burrs 18 are likely to be formed.

[0022] Returning to FIG. 1, in order to remove the burrs 18, the inside of the groove portion 16 provided in the molded body 10 is processed (step S12). FIG. 3(a) is a top view showing the molded body 10 in the first embodiment during processing, FIG. 3(b) is a side view seen from the A direction of FIG. 3(a), and FIG. 3(c) is a side view seen from the B direction of FIG. 3(b). In FIG. 3(a) to FIG. 3(c), the processing device 30 is hatched for clarity (the same applies to the following similar figures). In FIG. 3(a) and FIG. 3(b), the intermediate state of the molded body 10 during movement is illustrated by dotted lines. As shown in FIG. 3(a) to FIG. 3(c), the processing device 30 used for processing the molded body 10 includes a processing unit 32 and a holding unit 34 that holds the processing unit 32. The surface of the molded body 10 is processed by moving on the processing unit 32 in the direction in which the processing unit 32 extends (the conveying direction). The processed portion 32 is, for example, a rail portion extending in the conveying direction while repeating valleys and peaks. The direction in which the molded body 10 is conveyed is defined as the X-axis direction, the vertical direction as the Z-axis direction, and the direction perpendicular to the X-axis direction and the Z-axis direction as the Y-axis direction.

[0023] The processing part 32 is formed of a material harder than the compact 10. The processing part 32 is formed of, for example, stainless steel, high speed steel, or cemented carbide. The surface of the processing part 32 may be coated with a grindstone or abrasive powder. The holding part 34 is formed of a material capable of holding the processing part 32, for example, metal. In the processing device 30, a gap 36 may be formed between the processing part 32 and the holding part 34 in the Y-axis direction perpendicular to the conveying direction.

[0024] Two processing parts 32 are provided side by side in parallel in the Y-axis direction. The number of processing parts 32 may be increased or decreased depending on the number of processed parts 19 (the number of grooves 16 in the first embodiment). By having two or more processing parts 32, the molded body 10 can be easily transported, and the molded body 10 whose posture changes due to processing can be stably held. The minimum length of the processing part 32 protruding from the holding part 34 in the Z-axis direction is greater than the depth of the groove 16 provided in the flange part 14a, and the width of the upper part of the processing part 32 in the Y-axis direction is smaller than the width of the groove 16 in the Y-axis direction. Therefore, the processing part 32 can be inserted into the groove 16. In order to remove burrs 18 generated on the inner surface 17 of the groove 16, the upper part of the processing part 32 is inserted into the groove 16 and placed so that the groove 16 is in contact with the processing part 32. Then, while moving the molded body 10 in the transport direction (+X direction) in which the processed portion 32 extends, the molded body 10 is repeatedly moved diagonally vertically downward and vertically upward along the valleys and peaks of the processed portion 32, thereby processing only the grooves 16 and removing burrs 18 generated on the inner surface 17 of the grooves 16. The molded body 10 moves in the transport direction (+X direction) as the processed portion 32 vibrates.

[0025] The groove 16 is placed on the processing section 32, and the molded body 10 is moved in the conveying direction (+X direction) while being repeatedly moved in a vertically downward and vertically upward directions different from the conveying direction (+X direction), so that the posture of the molded body 10 is such that the lower surface of the flange 14a is repeatedly tilted downward and upward in the conveying direction (+X direction) with respect to the horizontal plane. That is, the lower surface of the flange 14a of the molded body 10 is repeatedly tilted at an elevation angle (positive angle) and a depression angle (negative angle) with respect to the horizontal plane in the conveying direction. The contact between the processing section 32 and the groove 16 is repeatedly made into a line contact or a point contact. In the line contact and point contact, the processing energy, which is a combination of the first energy generated by the movement of the molded body 10 in the conveying direction (+X direction) and the second energy generated by the movement of the molded body 10 in the vertically downward and vertically upward directions, is concentrated at the contact portion. That is, both the first energy and the second energy are combined as processing energy and are concentrated as an impact on a part of the fine part of the groove part 16, which is the part to be processed 19, thereby allowing efficient processing of the part of the fine part. Therefore, even if the molded body 10 is small and lightweight, the inside of the groove part 16 can be properly processed and the burrs 18 can be removed. When the lower surface of the flange part 14a of the molded body 10 is repeatedly at an elevation angle (positive angle) and a depression angle (negative angle) with respect to the horizontal plane in the conveying direction, the position of the contact part is repeatedly at the front part of the groove part 16, which is the part to be processed, in the conveying direction and at the rear part of the conveying direction. In this way, the position to be processed always moves, and as a result, appropriate processing is performed over the entire groove part 16, which is the part to be processed. This will be described in detail with reference to Figures 4(a) and 4(b).

[0026] 4(a) and 4(b) are side views for explaining the processing by the processing unit 32. As shown in FIG. 4(a) and FIG. 4(b), since the molded body 10 changes its orientation to a vertically downward diagonal direction and a vertically upward diagonal direction, which are different from the conveying direction, the processed parts 19a and 19b are processed while changing the contact angle with the processing unit 32, not at a constant angle. The contact angle can change continuously from a positive angle to a negative angle, and from a negative angle to a positive angle, based on the conveying direction. As shown in FIG. 4(a), the processed part 19a on the front side of the conveying direction of the molded body 10 has a larger contact angle with the processing unit 32 located forward in the conveying direction than the valley when the molded body 10 passes through the valley, and at this time, the processing energy is concentrated and processed. As shown in FIG. 4(b), the contact angle between the processed portion 19b on the rear side of the conveying direction of the molded body 10 and the processing portion 32 located rearward of the valley in the conveying direction becomes larger when the molded body 10 passes through the valley, and at this time, the processing energy is concentrated and processed. In this way, the processed portions 19a and 19b are processed in the up, down, left and right directions while making various contact angles with the processing portion 32, not a constant angle. By repeatedly changing the orientation of the molded body 10, more reliable processing can be performed. In addition, according to this method, two parts of the processed portions 19a and 19b of the molded body 10 can be processed in one process in one processing portion 32. The two processed portions 19a and 19b are the part located on the front side and the part located on the rear side in the conveying direction of the molded body 10 as shown in FIG. 4(a) and FIG. 4(b), so that when the processed portions 19a and 19b are the groove portion 16, both ends of the groove portion 16 are processed. Moreover, by carrying out the processing through such a movement, the processed portions 19a, 19b can be made rounded.

[0027] In step S12, barrel polishing or the like for processing the entire surface of the molded body 10 may be performed before or after processing the molded body 10 using the processing device 30. Moreover, barrel polishing may be performed after step S14 described later, instead of being performed in step S12.

[0028] 1, after the processing of the molded body 10 is completed, the molded body 10 is subjected to a heat treatment (for example, at about 200° C.) (step S14), whereby a base body made of the molded body 10 is formed.

[0029] When manufacturing a coil component using the base formed according to the first embodiment, a conductor with an insulating coating is wound around shaft portion 12 to form a winding portion of a coil conductor, the conductor is led out from both ends of the winding portion into groove portion 16, and the conductor is connected to the metal film provided in groove portion 16 to form external electrodes. In this way, a wire-wound coil component is obtained.

[0030] As described above, according to the method for manufacturing a base body according to the first embodiment, as shown in FIG. 1, a molded body 10 is formed by pressure molding a mixture containing an inorganic powder and a resin (step S10). The groove portion 16, which is the processed portion 19 formed in the molded body 10, is placed on the processing portion 32 so that it is in contact with the processing portion 32, and the molded body 10 is moved in the conveying direction (+X direction) in which the processing portion 32 extends, while repeatedly moving the molded body 10 in a vertically diagonally downward direction and a vertically diagonally upward direction different from the conveying direction (+X direction), thereby processing the groove portion 16 (the processed portion 19) (step S12). Thereafter, the molded body 10 is heat-treated (step S14). According to this method, the contact between the processing portion 32 and the groove portion 16 is repeatedly made into a line contact or a point contact, and a processing energy, which is a combination of a first energy generated by the movement of the molded body 10 in the conveying direction (+X direction) and a second energy generated by the movement of the molded body 10 in a vertically diagonally downward direction and a vertically diagonally upward direction, is concentrated at the contact site of the line contact or point contact. That is, the first energy and the second energy are combined as processing energy and are concentrated as an impact on a small portion of the groove portion 16, which is the processed portion 19. Therefore, even if the molded body 10 is small and lightweight, the inside of the groove portion 16 can be properly processed. Therefore, the burrs 18 generated on the inner surface 17 of the groove portion 16 can be removed.

[0031] In the first embodiment, the processed portion 32 is a rail portion extending in the conveying direction (+X direction) while repeating valleys and peaks. By using such a processed portion 32, it is possible to easily realize the repeated movement of the molded body 10 in a vertically downward and vertically upward diagonal directions different from the conveying direction (+X direction) while moving the molded body 10 in the conveying direction (+X direction) in which the processed portion 32 extends.

[0032] In the first embodiment, the processed portion 19 of the molded body 10 processed by the processing unit 32 is the groove portion 16, which is a concave portion when the molded body 10 is viewed in cross section in a plane (YZ plane) perpendicular to the conveying direction (+X direction). As the size of the groove portion 16 becomes smaller with the miniaturization of electronic components, small media that can enter the groove portion 16 are used in surface processing using barrel polishing. For this reason, the weight of the media becomes lighter and the kinetic energy generated becomes smaller, so that the groove portion 16 cannot be properly processed and the burrs 18 cannot be removed. However, by placing the groove portion 16 on the processing unit 32 so that the groove portion 16 is in contact with the molded body 10 and moving the molded body 10 in the conveying direction (+X direction) in which the processing unit 32 extends while repeatedly moving the molded body 10 in a vertically diagonally downward direction and a vertically diagonally upward direction different from the conveying direction (+X direction), as described above, the inside of the groove portion 16 can be properly processed and the burrs 18 generated on the inner surface 17 of the groove portion 16 can be removed.

[0033] In the first embodiment, the width of the upper part of the processing part 32 in a direction (Y axis direction) perpendicular to the conveying direction (+X direction) is smaller than the width between the inner surfaces of the groove part 16 when viewed in cross section on a plane (YZ plane) perpendicular to the conveying direction (+X direction). This allows the upper part of the processing part 32 to be inserted into the groove part 16, and the inside of the groove part 16 can be processed.

[0034] In the first embodiment, the coil conductor wound around the shaft portion 12 is drawn out to the groove portion 16 provided in the flange portion 14a. Since the dimensions of such groove portion 16 are small, even if barrel polishing is performed, the weight of the media becomes light and the kinetic energy generated becomes small, so that the groove portion 16 may not be properly processed. However, by placing the groove portion 16 on the processing portion 32 so that the groove portion 16 is in contact with the processing portion 32, and moving the compact 10 in the conveying direction (+X direction) in which the processing portion 32 extends, while repeatedly moving the compact 10 in a vertically diagonally downward direction and a vertically diagonally upward direction different from the conveying direction (+X direction), the inside of the groove portion 16 can be properly processed as described above.

[0035] In the first embodiment, the processing unit 32 and the holding unit 34 face each other with a gap 36 therebetween. The processing unit 32 is vibrated to move the molded body 10 in the conveying direction (+X direction). The gap 36 is formed between the processing unit 32 and the holding unit 34, so that the vibrations for moving the molded body 10 in the conveying direction (+X direction) can be easily controlled independently for each of the two processing units 32. The gap 36 is also formed between the processing unit 32 and the holding unit 34, so that the processing waste processed by the processing unit 32 can be discharged into the gap 36, and the processing waste can be prevented from adhering to the molded body 10. In order to make it easier for the processing waste to be discharged into the gap 36, air may be sucked from the -Z side of the gap 36.

[0036] The processing device for processing the groove portion 16 which is a part of the molded body 10 is not limited to the processing device 30 shown in Figures 3(a) to 3(c), and may be another device. Modified examples of the processing device are shown below.

[0037] FIG. 5(a) is a top view of a processing device 30a of a first modified example according to the first embodiment, FIG. 5(b) is a side view seen from the A direction of FIG. 5(a), and FIG. 5(c) is a side view seen from the B direction of FIG. 5(b). As shown in FIG. 5(a) to FIG. 5(c), in the processing device 30a, no gap is formed between the processing unit 32 and the holding unit 34. The processing unit 32 may be fixed to the upper surface of the holding unit 34, or a part of the processing unit 32 may be embedded in the holding unit 34, or the embedded part may penetrate the holding unit 34. The other configurations are the same as those of the processing device 30, so the description will be omitted.

[0038] As in the processing device 30a, the processing unit 32 and the holding unit 34 are integrated without any gap therebetween, so that the holding strength of the processing unit 32 by the holding unit 34 is increased.

[0039] FIG. 6(a) is a top view of the processing device 30b of the second modified example according to the first embodiment, FIG. 6(b) is a side view seen from the A direction of FIG. 6(a), and FIG. 6(c) is a side view seen from the B direction of FIG. 6(b). As shown in FIG. 6(a) to FIG. 6(c), in the processing device 30b, the processing unit 32 and the conveying unit 38 are fixed to the upper surface of the holding unit 34. The conveying unit 38 extends in the X-axis direction while repeating valleys and peaks, similar to the processing unit 32. The conveying unit 38 vibrates to move the molded body 10 in the conveying direction (+X direction) on the processing unit 32. In other words, the molded body 10 moves in the conveying direction (+X direction) on the processing unit 32 due to the vibration of the conveying unit 38. The processing unit 32 vibrates to process the molded body 10. The processing unit 32 may have a larger surface roughness than the conveying unit 38. A gap may be formed between the processing unit 32 and the conveying unit 38. The other configuration is the same as that of the processing device 30, so the description will be omitted.

[0040] Like the processing device 30b, a conveying unit 38 may be provided in addition to the processing unit 32. The conveying unit 38 may be vibrated to move the molded body 10 in the conveying direction (+X direction), and the processing unit 32 may be vibrated to process the inside of the groove portion 16 that is a part of the molded body 10. This makes it possible to vibrate the conveying unit 38 with a vibration suitable for conveying the molded body 10 and vibrate the processing unit 32 with a vibration suitable for processing the molded body 10, thereby achieving both efficient conveyance and processing.

[0041] FIG. 7(a) is a top view of the processing device 30c of the third modified example according to the first embodiment, FIG. 7(b) is a side view seen from the A direction of FIG. 7(a), and FIG. 7(c) is a side view seen from the B direction of FIG. 7(b). FIG. 7(a) to FIG. 7(c) show the molded body 10 moving on the processing unit 32. In the processing device 30b of the second modified example according to the first embodiment described above, the processing unit 32 and the conveying unit 38 both extend in the X-axis direction while repeating valleys and peaks. In contrast, in the processing device 30c of the third modified example according to the first embodiment, as shown in FIG. 7(a) to FIG. 7(c), the conveying unit 38 extends in the X-axis direction while repeating valleys and peaks, but the processing unit 32a extends in the X-axis direction at a constant height. In addition, a gap 36 is formed between the processing unit 32a and the conveying unit 38.

[0042] As in the processing device 30c, the processing unit 32a may extend in the X-axis direction at a constant height, and the transport unit 38 may extend in the X-axis direction while repeating valleys and peaks. In this case, by setting the distance between the upper surface of the processing unit 32a and the upper surface of the transport unit 38 to an appropriate size, the molded body 10 can be moved in the transport direction (+X direction) while being moved vertically diagonally upward and vertically diagonally downward by the valleys and peaks of the transport unit 38.

[0043] FIG. 8(a) is a top view of a processing device 30d of a fourth modified example according to the first embodiment, and FIG. 8(b) is a side view seen from the A direction of FIG. 8(a). In FIG. 8(a) and FIG. 8(b), a molded body 10 moving on a processing unit 32 is illustrated. As shown in FIG. 8(a) and FIG. 8(b), in the processing device 30d, the processing unit 32 is fixed to the upper surface of the holding unit 34 and extends in the conveying direction (+X direction) while bending in the left-right direction (Y-axis direction) in a top view. The maximum amplitude value of the portion of the processing unit 32 bending in the Y-axis direction, that is, the distance in the Y-axis direction between the portion of the processing unit 32 that is bent in the +Y direction to the portion of the processing unit 32 that is bent in the -Y direction to the maximum, is set to be smaller than the width of the groove portion 16, which is the opening width of the processed portion 19. The other configurations are the same as those of the processing device 30, so a description thereof will be omitted.

[0044] As in the processing device 30d, the processing section 32 is bent in the left-right direction (Y-axis direction) in top view, so that the molded body 10 moving on the processing section 32 moves in the conveying direction (+X direction) while repeatedly turning to the right (-Y direction) or left (+Y direction) with respect to the processing section 32. Since gravity acts vertically downward on the molded body 10, the force of gravity is also applied when moving left and right, and the molded body 10 moves in the conveying direction (+X direction) while repeatedly moving horizontally to the right (-Y direction) perpendicular to a vertical direction different from the conveying direction (+X direction) and horizontally to the left (+Y direction) perpendicular to the vertical direction. The posture of the molded body 10 repeatedly tilts leftward and rightward with respect to the conveying direction (+X direction). That is, the surface including the processed portion 19 of the molded body 10 is at an elevation angle (positive angle) and a depression angle (negative angle) with respect to the horizontal plane in the conveying direction, and the molded body 10 is repeatedly turned to the right and left with respect to the conveying direction. As a result, as in the first embodiment, the processing energy, which is a combination of the first energy generated by the movement of the molded body 10 in the conveying direction (+X direction), the second energy generated by the movement of the molded body 10 diagonally downward and upward, and the third energy generated by the movement of the molded body 10 to the left and right with respect to the conveying direction (+X direction), is locally concentrated in a fine part of the processed portion 19. That is, the first energy, the second energy, and the third energy are combined as processing energy and are concentrated as an impact on a part of the fine part of the processed portion 19. Therefore, even if the molded body 10 is small and lightweight, the processed portion 19 can be appropriately processed and burrs can be removed. When the surface of the molded body 10 including the processed portion 19 is at an elevation angle (positive angle) and a depression angle (negative angle) with respect to the horizontal plane in the conveying direction, and the molded body 10 is repeatedly turned to the right and left in the conveying direction, the position of the contact portion is repeatedly at the front part of the surface of the processed portion 19 in the conveying direction and the rear part of the surface of the processed portion 19 in the conveying direction, and at the same time, is repeatedly at the left part of the surface of the processed portion 19 in the conveying direction and the right part of the surface of the processed portion 19 in the conveying direction. In this way, the processed position is constantly moving, and as a result, appropriate processing is performed over the entire surface of the processed portion 19. Therefore, the entire inside of the groove portion 16, which is the processed portion 19, can be processed evenly.Therefore, the burrs 18 generated on the inner surface 17 of the groove portion 16 can be effectively removed.

[0045] 9(a) and 9(b) are top views showing other examples of bending of the processed portion 32. In the bending of FIG. 9(a) and FIG. 9(b), similarly to the bending of FIG. 8(a), the maximum amplitude value of the portion of the processed portion 32 bent in the Y-axis direction, i.e., the distance in the Y-axis direction between the portion of the processed portion 32 that is bent in the +Y direction to the portion of the processed portion 32 that is bent in the -Y direction to the maximum, is set smaller than the width of the groove portion 16, which is the opening width of the processed portion 19, but in FIG. 9(a) and FIG. 9(b), the maximum amplitude width is illustrated large for clarity of the drawing. In FIG. 8(a), the processed portion 32 is bent in a triangular wave shape as viewed from above, but as shown in FIG. 9(a), the processed portion 32 may be bent in a sine wave shape as viewed from above. That is, bending of the processed portion 32 in the left-right direction (Y-axis direction) includes bending in a triangular wave shape and bending in a sine wave shape.

[0046] In addition, in FIG. 8(a), the interval between the two processed parts 32 is constant in the conveying direction (+X direction), but as shown in FIG. 9(b), the interval between the two processed parts 32 may change in the conveying direction (+X direction). In the case of FIG. 9(b), the processed parts 32 may be sinusoidally bent in a top view. In this way, the width of the processed parts 32 in the Y-axis direction changes in the conveying direction (+X direction), so that the clearance, which is the difference between the width of the processed parts 32 in the Y-axis direction and the opening width of the groove parts 16, which are the processed parts 19, changes depending on the position in the conveying direction. For this reason, the molded body 10 tends to repeatedly move to the left (+Y direction) or to the right (-Y direction) with respect to the processed parts 32. For this reason, the processed position always moves, and the entire inner surface 17 of the groove parts 16, which are the processed parts 19, can be evenly processed, and the burrs 18 generated on the inner surface 17 of the groove parts 16 can be well removed.

[0047] In the above first embodiment, the molded body 10 is a drum core, but it may be a T core or other type of core.

[0048] [Second embodiment] In the first embodiment, the case where the groove 16 provided in the flange 14a is machined is shown as an example. In other words, the case where the groove 16 is the processed part 19 is shown as an example. In the present second embodiment, an example where the shaft 12 is machined is shown. That is, in the present second embodiment, an example where the shaft 12 is the processed part 19 is shown as an example. Burrs may also be generated on the side surface of the shaft 12 due to pressure molding when forming the molded body 10. In the present second embodiment, the distance between the flange 14a and the flange 14b (in other words, the axial length of the shaft 12) is 0.5 mm or less.

[0049] The flowchart of the method for manufacturing a substrate according to the second embodiment is the same as that of the first embodiment shown in FIG. 1, and is therefore omitted from the drawings. FIG. 10(a) is a top view showing the processing of the molded body 10 in the second embodiment, FIG. 10(b) is a side view seen from the direction A in FIG. 10(a), and FIG. 10(c) is a side view seen from the direction B in FIG. 10(b). In FIG. 10(a) and FIG. 10(b), the intermediate state of the molded body 10 during its movement is shown by dotted lines. As shown in FIG. 10(a) to FIG. 10(c), the processing device 30e has one processing unit 32 fixed to the upper surface of the holding unit 34.

[0050] The length of the processed portion 32 protruding from the holding portion 34 in the Z-axis direction is longer than the length between the side surfaces of the flanges 14a and 14b and the side surfaces of the shaft portion 12, and the width of the processed portion 32 in the Y-axis direction is smaller than the distance between the flanges 14a and 14b. Therefore, the processed portion 32 can be inserted into the gap between the flanges 14a and 14b. In order to remove burrs generated on the side surfaces of the shaft portion 12, the upper part of the processed portion 32 is inserted into the gap between the flanges 14a and 14b, and the shaft portion 12 is placed so that it is in contact with the processed portion 32. Then, while moving the molded body 10 in the conveying direction (+X direction) in which the processed portion 32 extends, the molded body 10 is repeatedly moved vertically diagonally downward and vertically diagonally upward along the valleys and peaks of the processed portion 32, thereby processing the shaft portion 12. While moving the molded body 10 in the conveying direction (+X direction), the molded body 10 is repeatedly moved in a vertically downward and vertically upward directions different from the conveying direction (+X direction), so that the surface of the processed part of the shaft part 12 of the molded body 10 is repeatedly tilted downward and upward in the conveying direction with respect to the horizontal plane. That is, the surface of the processed part of the shaft part 12 of the molded body 10 is repeatedly tilted at an elevation angle (positive angle) and a depression angle (negative angle) with respect to the horizontal plane in the conveying direction. As a result, as in the first embodiment, the processing energy, which is a combination of the first energy generated by the movement of the molded body 10 in the conveying direction (+X direction) and the second energy generated by the movement of the molded body 10 in the vertically downward and vertically upward directions, is locally concentrated on a fine part of the shaft part 12. That is, both the first energy and the second energy are combined as processing energy and concentrated as an impact on a fine part of the shaft part 12, which is the processed part 19. Therefore, even if the molded body 10 is small and lightweight, the shaft portion 12 can be appropriately machined and burrs can be removed. When the surface of the processed portion of the shaft portion 12 of the molded body 10 is repeatedly tilted up (positive angle) and down (negative angle) with respect to the horizontal plane in the conveying direction, the position of the contact portion is repeatedly moved to the front part of the surface of the processed portion of the shaft portion 12 in the conveying direction and to the rear part of the surface in the conveying direction. In this way, the position to be machined is constantly moving, and as a result, the entire surface of the processed portion of the shaft portion 12 is appropriately machined.

[0051] In the method for manufacturing a base according to the second embodiment, a molded body 10 is formed by pressurizing a mixture containing an inorganic powder and a resin. The shaft portion 12, which is the processed portion 19 of the molded body 10, is placed on the processing portion 32 so that the shaft portion 12 is in contact with the processing portion 32. The molded body 10 is moved in the conveying direction (+X direction) in which the processing portion 32 extends, while the molded body 10 is repeatedly moved in a vertically diagonally downward direction and a vertically diagonally upward direction different from the conveying direction, to process the shaft portion 12 (the processed portion 19). Thereafter, the molded body 10 is heat-treated. According to this method, as in the first embodiment, the contact between the processing portion 32 and the shaft portion 12 is repeatedly made into a line contact or a point contact, and a processing energy, which is a combination of a first energy generated by the movement of the molded body 10 in the conveying direction (+X direction) and a second energy generated by the movement of the molded body 10 in the vertically diagonally downward direction and the vertically diagonally upward direction, is concentrated at the contact site of the line contact or the point contact. That is, the first energy and the second energy are combined as processing energy and are concentrated as an impact on a small portion of the shaft portion 12, which is the processed portion 19. Therefore, even if the molded body 10 is small and lightweight, the shaft portion 12 can be properly processed. Therefore, burrs generated on the side surface of the shaft portion 12 can be removed.

[0052] In addition, in the second embodiment, the processed portion 19 of the molded body 10 processed by the processing unit 32 is the flanges 14a and 14b, which are concave portions, and the shaft portion 12 sandwiched therebetween when the molded body 10 is viewed in cross section on a plane (YZ plane) perpendicular to the conveying direction (+X direction). As electronic components become smaller, the gap between the flanges 14a and 14b becomes narrower, so that small media that can fit between the flanges 14a and 14b is used in surface processing using barrel polishing. For this reason, the weight of the media becomes lighter and the kinetic energy generated becomes smaller, so that the shaft portion 12 cannot be processed appropriately and burrs cannot be removed, and in particular, when the gap between the flanges 14a and 14b (in other words, the axial length of the shaft portion 12) is 0.5 mm or less, appropriate processing cannot be performed. However, by placing the shaft portion 12 on the processing portion 32 so that it is in contact with it, and moving the molded body 10 in the conveying direction (+X direction) in which the processing portion 32 extends, while repeatedly moving the molded body 10 diagonally downward and upward vertically in a direction different from the conveying direction (+X direction), as described above, the shaft portion 12 can be properly processed and burrs can be removed.

[0053] FIG. 11(a) is a top view of a processing device 30f of a first modified example according to the second embodiment, and FIG. 11(b) is a side view seen from the A direction of FIG. 11(a). As shown in FIG. 11(a) and FIG. 11(b), in the processing device 30f, the width of the processing part 32 in the Y-axis direction changes in the conveying direction (+X direction). The maximum value of the width of the processing part 32 in the Y-axis direction is set smaller than the interval between the flange parts 14a and 14b, which is the opening width of the processed part 19. In this way, the width of the processing part 32 in the Y-axis direction changes in the conveying direction (+X direction), so that the clearance, which is the difference between the width of the processing part 32 in the Y-axis direction and the interval between the flange parts 14a and 14b, which is the opening width of the processed part 19, changes depending on the position in the conveying direction. For this reason, the molded body 10 tends to repeatedly move to the left (+Y direction) or right (-Y direction) with respect to the processing part 32. In this way, since the processing position is always moving, for the same reason as in the first embodiment, the entire shaft portion 12 can be processed evenly, and burrs generated on the side surface of the shaft portion 12 can be effectively removed. Note that, even in the first embodiment, the width of the processing portion 32 in the Y-axis direction may change in the transport direction (+X direction).

[0054] In the second embodiment, since the molded body 10 moves in the transport direction (+X direction) on one processing section 32, there is a risk that the molded body 10 will lose balance and fall off the processing section 32. Therefore, guide sections may be provided on both sides of the molded body 10 in the Y axis direction and extending in the X axis direction along which the processing section 32 extends. This makes it possible to prevent the molded body 10 from falling off the processing section 32. In the first embodiment, guide sections may be provided on both sides of the molded body 10 in the Y axis direction. In any of the embodiments, the guide sections may be provided on only one side.

[0055] [Third embodiment] In the first and second embodiments, the case of removing burrs generated on the molded body 10 is shown as an example, but in the third embodiment, an example of forming a rounded edge formed by the side and lower surface of the flange portion 14a of the molded body 10 is shown. That is, in the third embodiment, the edge of the molded body 10 is the processed part. The flowchart of the method for manufacturing a base body according to the third embodiment is the same as that of the first embodiment shown in FIG. 1, and therefore is not shown. In the third embodiment, in step S12 of FIG. 1, the surface of the molded body 10 is processed to make the edge of the molded body 10 into a rounded shape. The edge is the boundary between the faces of the molded body 10.

[0056] The molded body 10 is placed on the processing unit 32 of the processing device 30 so that the ridgeline portion to be processed is in contact with the molded body 10, and while moving the molded body 10 in the conveying direction (+X direction) in which the processing unit 32 extends, the molded body 10 is repeatedly moved vertically downward and vertically upward in a direction different from the conveying direction (+X direction). By repeatedly moving the molded body 10 in the conveying direction (+X direction) and vertically downward and vertically upward in a direction different from the conveying direction (+X direction), the attitude of the molded body 10 is such that the surface including the ridgeline portion of the processed part is repeatedly tilted downward and upward in the conveying direction with respect to the horizontal plane. That is, the surface including the ridgeline portion of the processed part of the molded body 10 is repeatedly tilted downward and upward in the conveying direction with respect to the horizontal plane in the conveying direction at an elevation angle (positive angle) and a depression angle (negative angle). As a result, the ridgeline portion of the molded body 10 and the processing portion 32 do not form a constant angle, but the contact angle changes repeatedly, so that the ridgeline portion of the molded body 10 can be processed into a rounded shape (R shape). The ridgeline portion to be processed can be placed on the processing portion 32 in any direction, but is preferably placed so as to be perpendicular to the conveying direction (+X direction), that is, facing the Y direction. By placing the molded body 10 in such a direction, when the face including the ridgeline portion of the processed part is repeatedly tilted downward and upward in the conveying direction with respect to the horizontal plane, the amount of movement when the face including the ridgeline portion of the processed part is at an elevation angle (positive angle) with respect to the horizontal plane in the conveying direction and at a depression angle (negative angle) becomes large, and efficient processing can be performed. In this third embodiment, since the ridgeline portion of the molded body 10 is the processed part, the width in the Y direction of the processing portion 32 of the processing device 30 is larger than the width in the Y direction when the molded body 10 is placed on the processing portion 32. Since the molded body 10 is not shaped to hold the processed portion 32, guide portions may be provided on both sides of the molded body 10 in the Y-axis direction and extending in the X-axis direction along which the processed portion 32 extends. This makes it possible to prevent the molded body 10 from falling off the processed portion 32. In any of the embodiments, the guide portions may be provided on only one side.

[0057] 12(a) and 12(b) are views of the molded body 10 before surface processing, and 12(c) and 12(d) are views of the molded body 10 after surface processing. 12(a) and 12(c) are plan views of the molded body 10, 12(b) is a cross-sectional view taken along line AA in 12(a), and 12(d) is a cross-sectional view taken along line AA in 12(c). As shown in 12(a) to 12(d), the molded body 10 is placed on the processing section 32 so that the ridge line portion 20, which is the processed portion 19 of the molded body 10, is in contact with the processing section 32, and while moving the molded body 10 in the conveying direction (+X direction) in which the processing section 32 extends, the molded body 10 is repeatedly moved vertically downward and vertically upward in a direction different from the conveying direction (+X direction). As in the first and second embodiments, a processing energy, which is a combination of a first energy generated by the movement of the molded body 10 in the conveying direction (+X direction) and a second energy generated by the movement in the vertically diagonally downward and vertically diagonally upward directions, is locally concentrated on a fine portion of a ridgeline portion 20, which is the processed portion 19 of the molded body 10. That is, both the first energy and the second energy are combined as processing energy and are concentrated as an impact on a fine portion of a ridgeline portion 20, which is the processed portion 19 of the molded body 10. Therefore, even if the molded body 10 is small and lightweight, the ridgeline portion 20, which is the processed portion 19 of the molded body 10, can be appropriately processed and processed into a rounded shape. When the surface including the ridgeline portion 20, which is the processed portion 19 of the molded body 10, is repeatedly at an elevation angle (positive angle) and a depression angle (negative angle) with respect to the horizontal plane in the conveying direction, the position of the contact portion is repeatedly at the front part in the conveying direction of the surface including the ridgeline portion 20, which is the processed portion 19 of the molded body 10, and at the rear part in the conveying direction. This allows appropriate processing to be performed over the entire surface including the ridgeline portion 20, which is the processed portion 19 of the molded body 10. In particular, when the surface including the ridgeline portion 20 of the processed portion 19 is at an elevation angle (positive angle) with respect to the horizontal plane in the conveying direction, the amount of movement when it is at a depression angle (negative angle) becomes large, and efficient processing can be performed, so that the ridgeline portion 20 of the molded body 10 can be efficiently processed into a rounded shape (R shape).

[0058] In the third embodiment, as in the first and second embodiments, the processed portion 32 may extend in the conveying direction (+X direction) while bending in the left-right direction (Y-axis direction) in a top view. The maximum amplitude value of the portion of the processed portion 32 bent in the Y-axis direction, i.e., the distance in the Y-axis direction between the portion of the processed portion 32 that is bent in the +Y direction to the portion of the processed portion 32 that is bent in the -Y direction to the maximum, is set to be smaller than the width of the groove portion 16, which is the opening width of the processed portion 19. For this reason, the molded body 10 tends to repeatedly move to the left (+Y direction) or to the right (-Y direction) with respect to the processed portion 32. In this way, by constantly moving the processed position, the entire processed portion 19 of the molded body 10 can be evenly processed for the same reason as in the first and second embodiments, and the ridge portion 20, which is the processed portion 19 of the molded body 10, can be processed into a rounded shape (R shape).

[0059] In the above third embodiment, burrs 18 generated on the molded body 10 may be removed by the processing portion 32, and then the ridge portion 20 of the molded body 10 may be processed by the processing portion 32 to give it a rounded shape.

[0060] Although the embodiment of the present invention has been described in detail above, the present invention is not limited to such specific embodiment, and various modifications and variations are possible within the scope of the gist of the present invention described in the claims. [Explanation of symbols]

[0061] 10 Molded body 12 Shaft 14a, 14b Tsuba 16 Groove 17. Inside 18 Bali 19 Processed part 20 Ridge 30, 30a, 30b, 30c, 30d, 30e, 30f processing equipment 32 Processing Department 34 Holding part 36 void 38 Conveyor

Claims

1. A step of forming a molded body by pressure molding a mixture containing an inorganic powder and a resin; a step of placing a processed portion, which is a part of the molded body, on a rail portion, which is a processing portion of a processing device, so that the processed portion is in contact with the rail portion, and while moving the molded body in a conveying direction in which the rail portion extends, repeatedly moving the molded body in a vertically downward diagonal direction and a vertically upward diagonal direction different from the conveying direction, thereby processing the processed portion, which is a part of the molded body; and heat treating the molded body.

2. A method for manufacturing a base body of a coil component as described in claim 1, wherein the rail portion extends in the conveying direction while repeating valley portions and peak portions.

3. The method for manufacturing a base body of a coil component according to claim 2 , wherein the rail portion extends in the transport direction while bending in a left-right direction in a top view.

4. The method for manufacturing a base body of a coil component according to claim 1 , wherein the processed portion, which is a part of the molded body, is a concave portion when the molded body is viewed in cross section on a plane perpendicular to the transport direction.

5. A method for manufacturing a base body of a coil component as described in Claim 4, wherein the width of the upper part of the rail portion in a direction perpendicular to the conveying direction is smaller than the width between the inner surfaces of the concave portion when viewed in cross section on a plane perpendicular to the conveying direction.

6. 6. The method for manufacturing a base body of a coil component according to claim 4 or 5, wherein the molded body comprises a shaft portion around which a coil conductor is wound, and a flange portion provided at an end of the shaft portion and having the concave portion through which the coil conductor is pulled out.

7. The method for manufacturing a base body of a coil component according to claim 1 , wherein the processed portion which is a part of the molded body is a ridge portion of the molded body.

8. A method for manufacturing a base body of a coil component described in any one of claims 1 to 7, wherein the width of the upper part of the rail portion in a direction perpendicular to the conveying direction changes in the conveying direction.

9. the processing device includes the rail portion and a holding portion that faces the rail portion across a gap in a direction perpendicular to the transport direction and holds the rail portion, The method for manufacturing a base body of a coil component according to claim 1 , wherein the rail portion is vibrated to move the compact in the transport direction.

10. The processing device includes the rail unit and a conveying unit, The method for manufacturing a base body of a coil component according to any one of claims 1 to 8, further comprising vibrating the conveying section to move the molded body in the conveying direction and vibrating the rail section to process the processed portion, which is a part of the molded body.

Images