How to fix the nest

Abstract

To provide a nest fixing method that enables a nest to be stably fixed to a mold, and a nest manufacturing method.SOLUTION: A nest is formed with a fixing hole by a lamination shaping method including a sintering step. A nest fixing method for fixing the nest to a mold includes: a member-to-be-engaged member fixing step of fixing a member-to-be-engaged with an engagement hole by inserting the member-to-be-engaged into the fixing hole so as to expose the engagement hole; and a nest fixing step of fixing the nest to the mold by inserting an engagement member, which can be engaged with the engagement hole, into the engagement hole via the mold and fixing the engagement member.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a method for fixing a nest and a method for manufacturing a nest. [Background technology]

[0002] Conventionally, as described in Patent Document 1, for example, there is known a technique for manufacturing die-casting parts using an additive manufacturing method. The additive manufacturing method includes a material extrusion method and an inkjet method. For example, in the material extrusion method, a thermoplastic resin is melted by heat, and the molten resin is ejected from a nozzle to form layers, which are then repeatedly stacked one by one to form a shape. After that, the excess binder of the molded object is degreased, and the molded object is placed in a furnace and sintered. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-93264 A Summary of the Invention [Problem to be solved by the invention]

[0004] The additive manufacturing method involving sintering is applied to various technical fields, and is used, for example, in the manufacture of inserts for molds. The inserts have fixing holes into which bolts are inserted to fix the inserts to the mold. However, when an insert having fixing holes is manufactured using the additive manufacturing method involving sintering, the inserts shrink due to the sintering, and as a result, the shape of the fixing holes is deformed. This causes a problem that, depending on the degree of shrinkage of the fixing holes, it is not possible to accurately insert the bolts into the fixing holes. Therefore, a technology capable of stably fixing the inserts to the mold is desired. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms. According to one aspect of the present disclosure, there is provided a method for fixing a nest to a die, the method for fixing a nest to a die, the nest being formed with a fixing hole by an additive manufacturing method including a sintering step, the method comprising: an engaged member fixing step of inserting and fixing an engaged member having an engagement hole into the fixing hole so that the engagement hole is exposed, and an engaged member fixing step of inserting and fixing an engaging member engageable with the engagement hole into the engagement hole via the die, thereby fixing the nest to the die, a screw groove is formed on the inner periphery of the engagement hole, a screw thread that screws into the screw groove is formed on the outer periphery of the engaging member, and the engaged member has a cylindrical shaft portion and a flange portion provided at a tip of the shaft portion so as to protrude outward. the fixing hole has a first hole portion formed so that the flange portion can be inserted therethrough, and a second hole portion formed so that the flange portion can rotate around the shaft portion with the flange portion inserted therein, the first hole portion and the second hole portion being arranged in succession in an order along an insertion direction of the engaging member into the engaged member, and the engaged member fixing process includes a reaching process of inserting the engaged member into the first hole portion from the flange portion side and causing the flange portion to reach the second hole portion, and an engaging process of engaging the engaged member with the fixing hole in the axial direction of the shaft portion by rotating the flange portion around the shaft portion within the second hole portion after the reaching process.

[0006] (1) According to one aspect of the present disclosure, there is provided a method for fixing a nest to a die, the method including: an engaged member fixing step of inserting and fixing an engaged member having an engagement hole into the fixing hole so that the engagement hole is exposed; and a nest fixing step of inserting and fixing an engaging member engageable with the engagement hole from the die side into the engagement hole to fix the nest to the die. According to this embodiment, in the engaged member fixing step, the engaged member is inserted into the fixing hole of the nest formed through the sintering step. Then, in the nest fixing step, the engaging member is inserted into the engaging hole formed in the engaged member, thereby fixing the nest to the mold. Therefore, the engaging hole into which the engaging member is inserted is not affected by the sintering step when forming the nest, and its shape is not deformed due to shrinkage. In other words, since the engaged member is assembled after sintering, the engaging hole of the engaged member is maintained without distortion. Therefore, the engaging member can be reliably inserted into the engaging hole of the engaged member, and the nest can be stably fixed to the mold. (2) In the above embodiment, a screw groove may be formed on the inner periphery of the engagement hole, and a screw thread may be formed on the outer periphery of the engagement member to screw into the screw groove. According to this embodiment, the insert can be fixed to the die by screwing the engaged member, on which the screw groove is formed, to the engagement member, on which the screw thread is formed. Therefore, the insert can be easily fixed to the die with simple components. (3) In the above embodiment, the engaged member may be configured to have a cylindrical shaft portion and a flange portion protruding outward from the tip of the shaft portion, the fixing hole may have a first hole portion formed to allow the flange portion to be inserted therethrough, and a second hole portion formed to allow the flange portion to rotate around the shaft portion with the flange portion inserted, the first hole portion and the second hole portion being arranged in succession in an order along an insertion direction of the engaging member into the engaged member, and the engaged member fixing process may include a reaching process of inserting the engaged member into the first hole portion from the flange portion side and causing the flange portion to reach the second hole portion, and an engaging process of engaging the engaged member with the fixing hole in the axial direction of the shaft portion by rotating the flange portion around the shaft portion within the second hole portion after the reaching process. According to this embodiment, the flange portion of the engaged member engages with the second hole portion in the axial direction, so that the engaged member can be prevented from coming out of the fixing hole in the axial direction. The fixing hole has a first hole portion formed so that the flange portion can be inserted therethrough, and a second hole portion formed so that the flange portion can be inserted therein and can rotate about the shaft portion. Therefore, in the engaging step after the reaching step, the engaged member can be easily engaged with the fixing hole in the axial direction by a simple action of rotating the flange portion around the shaft portion within the second hole portion. (4) In the above embodiment, the nest is formed having a plurality of fixing holes, and the nest fixing process includes a step of inserting a first engaging member, which is the engaging member, into the engaged member fixed to a first fixing hole of the plurality of fixing holes via the mold to fix the engaged member, and a step of inserting a second engaging member into a second fixing hole of the plurality of fixing holes via the mold without passing through the engaged member, and the second fixing hole may be located closer to the center of sintering shrinkage when the nest is sintered than the first fixing hole. According to this embodiment, the second engaging member can be directly inserted through a die into the second fixing hole located near the center of sintering shrinkage when the insert is sintered, without going through an engaged member. The portion located near the center of sintering shrinkage is not easily affected by heat-induced shrinkage when the insert is sintered. Therefore, the fixing hole located near the center of sintering shrinkage is less likely to deform in its inner diameter due to sintering, and can be directly fixed by the second engaging member. Since the second fixing hole located near the center of sintering shrinkage does not go through an engaged member, the number of parts can be reduced, and costs can be reduced. In addition, the first fixing hole is located away from the center of sintering shrinkage and is easily affected by heat-induced shrinkage during the sintering process, so the first engaging member can be inserted through a die into the engaged member fixed to the first fixing hole and fixed thereto, thereby allowing the insert to be stably fixed to the die. (5) According to a second aspect of the present disclosure, there is provided a method for manufacturing a nest, the nest being fixed to a mold, the nest being fixed to the mold by engagement between an engaged member having an engagement hole and fixed to the nest and an engaging member inserted into the engagement hole from the mold side, the method including a molding step of additively manufacturing a shaped body having a fixing hole into which the engaged member is inserted and having an external shape of the nest, and a sintering step of sintering the shaped body additively manufactured in the molding step. According to this embodiment, the insert can be manufactured inexpensively through the molding process and the sintering process. The insert can then be easily fixed to the die by engaging the engaged member having an engagement hole and fixed to the insert with the engaging member inserted into the engagement hole from the die side. [Brief description of the drawings]

[0007] [Figure 1] 1 is a cross-sectional view showing a schematic state in which an insert is fixed to a casting mold by a method for fixing an insert according to a first embodiment of the present disclosure. FIG. [Diagram 2] FIG. [Diagram 3] 10 is a flowchart showing the steps of a method for manufacturing a nest. [Figure 4]13 is a flowchart showing the steps of a method for fixing the nest. [Diagram 5] 10 is a flowchart showing a detailed procedure of a nut fixing step. [Figure 6] FIG. 11 is a cross-sectional view that illustrates a schematic state in which an insert is fixed to a casting mold by a method for fixing an insert according to a second embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] A. First embodiment: A1.Mold configuration: A first embodiment of the present disclosure will be described below with reference to Fig. 1 to Fig. 5. Fig. 1 is a cross-sectional view that shows a schematic state in which an insert 2a is fixed to a casting mold 1a by a method for fixing an insert 2a according to the first embodiment of the present disclosure. As shown in Fig. 1, the metal insert 2a has a plurality of fixing holes 10 (two in this embodiment) and an insert nut 20 to be inserted into the fixing hole 10.

[0009] FIG. 2 is a plan view showing the insert nut 20, and is a view of the insert nut 20 seen from the shaft portion 21 side described later. The insert nut 20 corresponds to the "engaged member". Hereinafter, the insert nut 20 is also simply referred to as the "nut 20". As shown in FIGS. 1 and 2, the insert nut 20 has a shaft portion 21 and a flange portion 22 integrally provided at the tip of the shaft portion 21 and protruding outward, and the cross section passing through the central axis C1 of the nut 20 is T-shaped. The shaft portion 21 is cylindrical. An engagement hole 23 is formed at the center of the shaft portion 21, extending in the axial direction and penetrating the shaft portion 21. A screw groove 24 (see FIG. 2) is formed on the inner circumference of the engagement hole 23. The flange portion 22 is thin plate-shaped, and the outer shape in a plan view is a substantially elliptical shape with a central portion corresponding to the shaft portion 21 penetrating. The nut 20 is manufactured by cutting or the like from a metal material such as stainless steel, and is manufactured by a method other than an additive manufacturing method including a sintering process. In other words, the shape precision of the nut 20 is high.

[0010] The fixing hole 10 is a hole formed in the end face 3 of the insert 2a (see FIG. 1). The insert nut 20 can be inserted into the fixing hole 10 from the flange portion 22 side. The fixing hole 10 is configured to have a first hole portion 11 and a second hole portion 12, in this order from the end face 3 side of the insert 2a into which the nut 20 is inserted. The first hole portion 11 and the second hole portion 12 are coaxially arranged in succession in the order along the insertion direction of the nut 20.

[0011] The first hole portion 11 is a portion that houses the shaft portion 21 of the nut 20, and has a shape corresponding to the outer shape of the shaft portion 21. The cross-sectional shape perpendicular to the axis of the first hole portion 11 is substantially the same as the outer shape of the flange portion 22 of the nut 20 (see FIG. 2). The first hole portion 11 is formed so that the flange portion 22 can be inserted therethrough. Note that the nut 20 shown by the solid line in FIG. 2 is in a state when passing through the first hole portion 11.

[0012] The second hole portion 12 is a portion that houses the flange portion 22 of the nut 20. The cross-sectional shape of the second hole portion 12 on a plane perpendicular to the central axis C1 is a circle with a diameter that is approximately the same length as the major axis of the flange portion 22 (see FIG. 2). The second hole portion 12 is formed so that the flange portion 22 is inserted therein and can rotate around the shaft portion 21. The second hole portion 12 has a portion that does not overlap with the opening of the first hole portion 11 when projected in a direction perpendicular to the opening.

[0013] The fixing hole 10 can be inserted into the first hole 11 from the flange portion 22 side of the insert nut 20, and the nut 20 is formed to be rotatable around the shaft portion 21 after the flange portion 22 is inserted into the second hole portion 12. The axial height of the second hole portion 12 is designed with a dimensional tolerance that allows the flange portion 22 to rotate. In FIG. 2, the nut 20 after rotation is shown by a two-dot chain line. Note that after the nut 20 rotates a predetermined angle in the direction of the arrow A, for example, rotation beyond the predetermined angle is restricted, and the nut 20 is fixed in the fixing hole 10. As a rotation prevention structure that restricts the rotation of the nut 20 beyond the predetermined angle, for example, a protrusion (not shown) may be provided at a predetermined position in the second hole portion 12, and the side of the flange portion 22 of the nut 20 after rotation may abut against the protrusion.

[0014] Referring again to FIG. 1, in the mold 1a, an insertion hole 6 into which a bolt 30 is inserted is formed penetrating the outer wall 5 in the outer wall 5 corresponding to the cavity 4 to which the insert 2a is fixed. The positions of the fixing holes 10 formed in the insert 2a and the positions of the insertion holes 6 for the bolts 30 formed in the mold 1a correspond to each other, and when the insert 2a is placed in the cavity 4, the corresponding fixing holes 10 and the insertion holes 6 communicate with each other via the end face 3 of the mold 1a. The insert 2a is firmly fixed in the cavity 4 of the mold 1a by fastening the nut 20 fixed to the insert 2a and the bolt 30 inserted from the outside of the outer wall 5 of the mold 1a through the insertion hole 6 to the engagement hole 23. The bolt 30 corresponds to an "engagement member" that has a screw thread 32 formed on its outer periphery and can engage with the engagement hole 23.

[0015] A2. Manufacturing method of the nest: Next, a method for manufacturing the insert 2a will be described. FIG. 3 is a flow chart showing the steps of the method for manufacturing the insert 2a. In this embodiment, the insert 2a is manufactured by a material extrusion method. As shown in FIG. 3, in the method for manufacturing the insert 2a, first, a molding process is performed in step 10 (hereinafter, step is abbreviated as "S"), and then a sintering process is performed in S20. In the molding process (S10), a molded body having fixing holes 10 and forming the outer shape of the insert 2a is layer-modeled. In the sintering process (S20), the molded body layer-modeled in the molding process (S20) is placed in a furnace and sintered.

[0016] A3.How to fix the nest: Next, a method for fixing the insert 2a manufactured by the above-mentioned method for manufacturing an insert to the die 1a will be described. In the method for fixing the insert 2a in the first embodiment, a nut 20 is inserted into a fixing hole 10 formed in the insert 2a to fix it in the fixing hole 10, and a bolt 30 is fastened to the nut 20 to fix the insert 2a to the die 1a.

[0017] Fig. 4 is a flow chart showing the procedure of the method for fixing the insert 2a in the first embodiment. As shown in Fig. 4, in the method for fixing the insert 2a, first, a nut fixing step is performed in S30, and then, an insert fixing step is performed in S40. In the nut fixing step (S30), the nut 20 is inserted into the fixing hole 10 so that the engagement hole 23 is exposed, and fixed to the insert 2a. In the insert fixing step (S40), the insert 2a is fixed to the die 1a by the bolt 30. The nut fixing step (S30) corresponds to the "engaged member fixing step".

[0018] FIG. 5 is a flow chart showing the detailed procedure of the nut fixing step (S30). As shown in FIG. 5, in the nut fixing step (S30), first, a reaching step is performed in step S31, and then an engaging step is performed in step S32. In the reaching step (S31), the nut 20 is inserted into the first hole portion 11 from the flange portion 22 side, and the flange portion 22 is caused to reach the second hole portion 12. In the engaging step (S32), the nut 20 is rotated around the shaft portion 21, so that the flange portion 22 is engaged with the second hole portion 12 in the axial direction. When the nut 20 is rotated, as shown by the two-dot chain line in FIG. 2, the end portion 25 in the longitudinal direction of the flange portion 22 abuts against the surface 13 (see FIG. 1) on the end surface 3 side of the second hole portion 12 in the axial direction. Therefore, the nut 20 is prevented from falling off in the axial direction.

[0019] The sintering step (S20) causes the molded object to shrink. Here, the fixing hole 10 is also affected by heat and shrinks. However, the fixing hole 10 does not shrink to an extent that the nut 20 cannot be inserted. If the fixing hole 10 is, for example, a hole into which the bolt 30 is directly screwed, rather than a hole for inserting the nut 20, it will have a smaller diameter than a hole for inserting the nut 20 and will have a fine shape such as a screw groove, so it will be more significantly affected by heat and the degree of deformation of the hole may become so large that the bolt 30 cannot be inserted. In other words, if the fixing hole 10 is a hole into which the bolt 30 is directly screwed, a certain degree of high shape accuracy is required.

[0020] In this respect, as in the present embodiment, the fixing hole 10 into which the nut 20 is inserted does not have a fine shape such as a screw groove, and does not require such high shape precision compared to the above-mentioned hole for inserting a bolt. In other words, the nut 20 does not shrink to an extent that makes it impossible to insert the nut 20, and the nut 20 can be inserted into the fixing hole 10 in the subsequent nut fixing step (S30).

[0021] (1) According to the method for fixing the insert 2a of the first embodiment, in the nut fixing step (S30), the nut 20 is inserted into the fixing hole 10 of the insert 2a formed through the sintering step (S20). Then, in the insert fixing step (S40), the bolt 30 is inserted into the engagement hole 23 formed in the nut 20, thereby fixing the insert 2a to the die 1a. That is, the engagement hole 23 into which the bolt 30 is inserted is not affected by the sintering step (S20) during the formation of the insert 2a, and therefore the shape is not deformed due to shrinkage. In other words, since the nut 20 is assembled after the sintering step (S20), the inner diameter of the nut 20 is maintained without distortion. Therefore, the bolt 30 can be reliably inserted into the engagement hole 23 of the nut 20, and the insert 2a can be stably fixed to the die 1a.

[0022] (2) Furthermore, since the insert 2a manufactured by a relatively inexpensive additive manufacturing method including the sintering step (S20) is used, costs can be reduced. For example, even if an insert having a fastening hole into which a bolt is directly inserted without using a nut 20 is manufactured by an additive manufacturing method that enables inexpensive manufacturing, the fastening hole may deform due to shrinkage, and re-machining may be required to achieve the accuracy of the fastening hole after the sintering process, which ultimately increases costs. In this regard, in the first embodiment, there is no need to re-machine the fastening hole 10 after the sintering step (S20), so costs can be stably reduced. This is particularly useful when manufacturing cast parts in small quantities.

[0023] (3) According to the method for fixing the insert 2a in the first embodiment, the nut 20 is used as the engaged member, and the bolt 30 is used as the engaging member. Therefore, the insert 2a can be easily fixed to the die 1a with simple components.

[0024] (4) According to the method for fixing the insert 2a of the first embodiment, in the nut fixing step (S30), the reaching step (S31) is performed, and then the engaging step (S32) is performed. By the engaging step (S32), the longitudinal end 25 of the flange portion 22 axially engages with the surface 13 on the side of the end face 3 of the second hole portion 12, so that the nut 20 can be prevented from falling off in the axial direction.

[0025] B. Second embodiment: Next, a method for fixing a core 2b according to a second embodiment of the present disclosure will be described with reference to Fig. 6. Note that the same reference numerals are used for configurations that are substantially the same as those in the first embodiment, and descriptions thereof will be omitted. Fig. 6 is a cross-sectional view that shows a schematic state in which a core 2b is fixed to a casting mold 1b by the method for fixing a core 2b according to the second embodiment of the present disclosure.

[0026] 6, the insert 2b of the second embodiment has, in addition to two first fixing holes 41, 42 into which nuts 20 are inserted, a second fixing hole 43 into which a bolt 31 is directly screwed without using a nut 20. The configuration of the first fixing holes 41, 42 is similar to the configuration of the fixing hole 10 of the first embodiment. A thread groove 44 is formed on the inner periphery of the second fixing hole 43.

[0027] The center of sintering shrinkage when the insert 2b is sintered in the sintering step (S20) is illustrated as shrinkage center C2 in FIG. 6. This shrinkage center C2 varies depending on the shape of the insert 2b and the installation environment in the furnace, and is determined in advance by simulation analysis, experiments, etc. Note that, when heat is uniformly applied to the insert in the installed state in the furnace, the shrinkage center C2 may substantially coincide with the centroid of the outer planar shape of the insert projected onto the installation surface in the furnace. The first fixing holes 41 and 42 are located at a position away from the shrinkage center C2. The second fixing hole 43 is located closer to the shrinkage center C2 than the first fixing holes 41 and 42.

[0028] In the method for fixing the insert 2b in the second embodiment, in the insert fixing step (S40), in addition to the step of fixing the insert 2b to the mold 1b by fastening the bolt 30 inserted from the insertion hole 6 of the mold 1b through the mold 1b to the engagement hole 23 and the nut 20 fixed to the first fixing hole 41, 42, as in the first embodiment, the method further includes the step of inserting and fixing the bolt 30 that screws directly into the second fixing hole 43 without using the nut 20, through the insertion hole 6 of the mold 1b through the mold 1b. In the second embodiment, the bolt 30 inserted into the first fixing hole 41, 42 corresponds to the "first engagement member", and the bolt 31 inserted into the second fixing hole 43 corresponds to the "second engagement member".

[0029] For example, when the insert 2b is large, such as having a size of 100 mm or more, the second fixing hole 43 close to the shrinkage center C2 of the insert 2b and the two fixing holes (first fixing holes 41, 42) far from the shrinkage center C2 will have different degrees of deformation after the sintering step (S20). This is because the shrinkage rate of the distant part is higher than that of the part near the shrinkage center C2.

[0030] Therefore, since the second fixing hole 43 formed in the vicinity of the contraction center C2 of the insert 2b has a small shrinkage rate due to sintering and the degree of deformation can be easily kept within the allowable range, it is possible to apply a fixing means by fastening the thread groove 24 formed in the second fixing hole 43 to the bolt 31 without using a nut 20. On the other hand, for a remote portion where the shrinkage rate is high and it is difficult to apply a fixing means without using a nut 20, it is preferable to apply a fixing means using the nut 20 and the bolt 30.

[0031] The method for fixing the insert 2b in the second embodiment provides the same effects as those in the first embodiment. Furthermore, since the nuts 20 are not used in the second fixing holes 43 in the vicinity of the contraction center C2 of the insert 2b, which is less affected by the contraction, as described above, the number of parts can be reduced, and the cost can be further reduced.

[0032] C. Other embodiments: (C1) In each of the above embodiments, the nut 20 having the flange portion 22 and the shaft portion 21 is used as the engaged member, but it may not have the flange portion 22 and is not limited to the nut 20 of the above shape. In addition, the shape of the fixing holes 10, 41, 42 can be changed as appropriate as long as the nut 20 can be fixed in the fixing hole corresponding to the shape of the inserted nut 20. For example, the second hole portion 12 has a perfect circle shape, but it does not have to be a perfect circle. It is sufficient that the flange portion 22 of the nut 20 can rotate a predetermined angle in the second hole portion 12 and does not fall out of the second hole portion 12.

[0033] (C2) Furthermore, as another configuration example of the fixing holes 10, 41, 42 and the nut 20, instead of the configuration in which the two holes 11, 12 are provided and the nut 20 is rotated in the second hole 12 as in each of the above embodiments, the following configuration may be used. For example, a slit-shaped groove extending in the axial direction may be formed on the inner circumference of the fixing holes 10, 41, 42, and the flange portion 22 of the nut 20 may be inserted into the groove, so that the nut 20 is locked at the end of the groove into which the nut 20 is inserted. Here, the groove may be formed so that the depth becomes shallower toward the end of the nut 20 insertion, and the nut 20 is gradually crimped in the groove at a stage where the nut 20 is inserted to a certain extent and fixed. According to this configuration, it is possible to perform a rotation prevention function and suppress the axial slippage. In addition, it is difficult to form a groove portion that is formed inside the fixing hole and has a changing depth as described above by cutting, but it can be easily manufactured by additive manufacturing.

[0034] (C3) In addition, in each of the above embodiments, nuts 20 are used as the engaged members and bolts 30 are used as the engaging members to fix the inserts 2a, 2b to the dies 1a, 1b, but the fastening between the nuts 20 and the bolts 30 is not essential. It is only necessary that the inserts 2a, 2b can be fixed to the dies 1a, 1b by engaging the engaging members with the engaged members inserted into the fixing holes 10, 41, 42 via the dies 1a, 1b.

[0035] (C4) In the above embodiments, the number and positions of the fixing holes 10, 41, 42, 43 are not limited to those described above.

[0036] The present disclosure is not limited to the above-mentioned embodiments, and can be realized in various configurations without departing from the spirit of the present disclosure. For example, the technical features in each embodiment corresponding to the technical features in each form described in the Summary of the Invention column can be appropriately replaced or combined in order to solve some or all of the above-mentioned problems or to achieve some or all of the above-mentioned effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted. [Explanation of symbols]

[0037] Reference Signs List 1a, 1b...casting mold, 2a, 2b...insert, 3...end face, 4...cavity, 5...outer wall, 6...insertion hole, 10...fixing hole, 11...first hole, 12...second hole, 13...surface, 20...insert nut (engaged member), 21...shaft, 22...flange, 23...engagement hole, 24...thread groove, 25...end, 30...bolt (first engaging member), 31...bolt (second engaging member), 32...thread, 41, 42...first fixing hole, 43...second fixing hole, 44...thread groove, C1...central axis, C2...center of sintering shrinkage

Claims

[Claim 1] A method for fixing a insert to a die, comprising the steps of: The insert is formed with a fixing hole by an additive manufacturing method including a sintering process, a fixing step of fixing an engaged member having an engagement hole by inserting the engaged member into the fixing hole so that the engagement hole is exposed; a nest fixing step of fixing the nest to the die by inserting and fixing an engagement member that is engageable with the engagement hole into the engagement hole via the die; Equipped with A screw groove is formed on the inner periphery of the engagement hole, A screw thread is formed on the outer periphery of the engaging member to screw into the screw groove, The engaged member is configured to have a cylindrical shaft portion and a flange portion provided at a tip end of the shaft portion so as to protrude outward, the fixing hole has a first hole portion formed so that the flange portion can be inserted therethrough, and a second hole portion formed so that the flange portion can rotate around the shaft portion with the flange portion inserted therein, the first hole portion and the second hole portion being disposed consecutively in an order along an insertion direction of the engaging member into the engaged member, The engaged member fixing step includes: a reaching step of inserting the engaged member into the first hole from the flange portion side and causing the flange portion to reach the second hole; and an engagement step of rotating the flange portion around the shaft portion in the second hole portion after the reaching step, thereby engaging the engaged member with the fixing hole in the axial direction of the shaft portion. How to fix the nesting.

Images