Stamped products, stamping equipment, stamping methods

Abstract

The stamped part (1) includes a main body (2), a recess (3), a pin (4), and a groove (5). The main body (2) is plate-shaped. The recess (3) is provided on a first surface (21) of the main body (2) facing the thickness direction. The pin (4) is provided on a second surface (22) of the main body (2) opposite to the first surface (21) at a position corresponding to the recess (3), and its shape in the thickness direction view of the main body (2) is shaped to be smaller than the recess (3) and protrude in the thickness direction of the main body (2). The groove (5) is recessed from the second surface (22) of the main body (2) toward the first surface (21), and is configured to surround at least a portion of the pin (4).

Description

[0001] Cross-reference of related applications

[0002] This application is based on Japanese Patent Application No. 2020-197452, filed on November 27, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to a stamped product, a stamping apparatus for manufacturing the stamped product, and a stamping method. Background Technology

[0004] Previously, it was known that a pin was formed on a plate-shaped component by stamping, and the pin of the component was inserted into a hole in another component, so that the two components were joined together by riveting or rolling riveting.

[0005] Patent Document 1 describes a structure in which the intermediate terminal and the connection terminal of a commutator are joined by riveting. Specifically, after a pin formed on the intermediate terminal (the protrusion in Patent Document 1) is inserted into a hole provided in the connection terminal (the fitting hole in Patent Document 1), a load is applied to the tip of the pin, causing the tip of the pin to deform, thereby joining the intermediate terminal and the connection terminal by riveting. Furthermore, after the intermediate terminal and the connection terminal are joined by riveting, they are molded together with the commutator components using resin.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2004-350374

[0009] In this case, when two parts are joined by riveting, increasing the height of the pin can improve the strength of the riveting joint. Therefore, when the pin for riveting is formed by stamping, it is desirable to increase the height of the pin.

[0010] Generally, in the case of forming a pin by stamping, a die and a punch with holes for forming the pin are prepared, and the workpiece is positioned between the die and the punch. Then, by moving the punch toward the hole side of the die, a portion of the material of the workpiece is pressed into the hole of the die, thereby forming a pin in the workpiece.

[0011] At this point, as a method to increase the height of the pin formed by stamping, one method is to shape the inner side of the hole in the die such that the inner diameter of the deep side is larger than the inner diameter of the inlet side. As a result, during stamping, the frictional resistance between the material of the workpiece pressed into the inner side of the die hole and the inner wall of the die hole is reduced, allowing the pin to be formed at a higher height.

[0012] However, in this method, if the material flow of the workpiece pressed into the inside of the die hole is uneven during stamping, the pin may bend deep inside the hole, making it impossible to maintain the straightness of the pin.

[0013] On the other hand, if in order to maintain the straightness of the pin, the inner diameter of the hole provided in the die is the same from the entrance side to the depth, then during the stamping process, the frictional resistance between the material of the workpiece pressed into the inner side of the die hole and the inner wall of the die hole increases, making it difficult to form the pin higher. Summary of the Invention

[0014] The purpose of this invention is to provide a stamped product, a stamping apparatus, and a stamping method that can ensure the straightness of the pin protruding from the main body and achieve a high degree of pin forming.

[0015] One aspect of the present invention relates to a stamped article. The stamped article includes a main body, a recess, a pin, and a groove. The main body is plate-shaped. The recess is provided on a first surface of the main body facing the thickness direction. The pin is provided on a second surface of the main body opposite to the first surface at a position corresponding to the recess, and its shape in the thickness direction view of the main body is formed to be smaller than the recess and protrude in the thickness direction of the main body. The groove is recessed from the second surface of the main body toward the first surface and is configured to surround at least a portion of the area around the pin.

[0016] Therefore, in manufacturing a stamped part with this shape, a first mold is prepared on the first surface side of the main body and a second mold is prepared on the second surface side of the main body. The first mold has a punch that forms a recess on the first surface of the main body and a ejector that presses the first surface on the outside of the punch. The second mold has a protrusion that forms a hole and a groove on the second surface of the main body. Then, during stamping, the main body, which is the workpiece, is placed between the first mold and the second mold. By punching the first surface of the main body to form a recess on the first surface side, the material of the main body is pressed out from the hole of the second mold to form a pin on the second surface side. At this time, since the material of the main body is blocked from flowing towards the surface of the second surface by the pressing force of the punch due to the protrusion of the second mold, the pushing force of the material of the main body pressed out towards the hole of the second mold is increased. Therefore, when a stamped part with this shape is manufactured by stamping, the straightness of the pin can be ensured, and the pin can be formed higher.

[0017] Furthermore, in this specification, stamping includes cold forging.

[0018] Another view relates to a stamping apparatus for manufacturing stamped articles. The stamping apparatus includes: a first die disposed on a first surface side of a plate-shaped main body portion of the stamped article facing the thickness direction; and a second die disposed on a second surface side of the main body portion opposite to the first surface.

[0019] The first mold has: a punch that forms a recess on a first surface of the main body; and a demolding device that presses against the first surface on the outside of the punch.

[0020] The second mold has: a base having a surface that contacts a second surface of the main body; a hole having a position corresponding to a punch and having a shape smaller than the punch in a thickness direction view of the main body, the hole having a pin protruding from the second surface; and a protrusion having a protrusion protruding from the base toward the first mold side and being configured to surround at least a portion of the periphery of the hole, the protrusion having a groove formed on the second surface.

[0021] Therefore, when manufacturing stamped parts using a stamping apparatus, a main body portion serving as the workpiece is positioned between a first die and a second die. A recess is formed on the first surface side by striking the main body portion with a punch, and material from the main body portion is pressed out through a hole in the second die to form a pin on the second surface side. At this time, because the protrusion of the second die prevents the material from flowing towards the surface of the second surface due to the pressing force of the punch, the pushing force of the material from the main body portion towards the hole in the second die increases. Therefore, this stamping apparatus can ensure the straightness of the pin formed on the stamped part and can form the pin at a higher elevation.

[0022] Another perspective concerns a stamping method for manufacturing stamped parts. This stamping method includes the following steps: First, a stamping apparatus is prepared, comprising a first die and a second die. The first die has a punch and a ejector. The punch forms a recess on a first surface of the main body of the stamped part facing the thickness direction. The ejector presses against the first surface outside the punch. The second die has a base, a hole, and a protrusion. The base has a surface that contacts a second surface of the main body located opposite the first surface. The hole is positioned corresponding to the punch and its shape in the thickness direction view of the main body is smaller than the punch. The hole forms a pin protruding from the second surface. The protrusion protrudes from the base toward the first die and is configured to surround at least a portion of the hole. The protrusion forms a groove on the second surface. Next, the main body of the stamped part, serving as the workpiece, is positioned between the first die and the second die. Then, the ejector is moved toward the second die, and at least a portion of the groove is formed on the second surface by the protrusion. Subsequently, the ejector is moved further toward the second mold side to form a groove on the second surface via a protrusion, and the punch is moved toward the second mold side to form a recess on the first surface and a pin through a hole. Next, the first mold is moved away from the second mold, and the stamped part is removed from between the first and second molds.

[0023] According to this stamping method, after the demolding device is moved toward the second die side and at least a portion of the groove is formed on the second surface by the protrusion, the punch is moved toward the second die side to form a recess on the first surface and a pin is formed through the hole. Therefore, when the punch moves toward the second die side, the material of the main body is prevented from flowing toward the surface of the second surface by the pressing force of the punch due to the protrusion that formed the groove in the previous step, thus increasing the pushing force of the material of the main body toward the hole of the second die. Therefore, according to this stamping method, the straightness of the pin formed on the stamped product can be ensured, and the pin can be formed at a higher elevation.

[0024] Furthermore, the parenthesized reference symbols marked on each structural element indicate an example of the correspondence between that structural element and the specific structural elements described in the embodiments described later. Attached Figure Description

[0025] Figure 1 This is a cross-sectional view of the stamped product according to the first embodiment.

[0026] Figure 2 yes Figure 1 View in direction II.

[0027] Figure 3 yes Figure 1 View in direction III.

[0028] Figure 4 yes Figure 1 An enlarged view of part IV.

[0029] Figure 5 This is a flowchart illustrating the manufacturing method of the stamped workpiece according to the first embodiment.

[0030] Figure 6 This is an explanatory diagram of the manufacturing process of the stamped product according to the first embodiment.

[0031] Figure 7 This is an explanatory diagram of the manufacturing process of the stamped product according to the first embodiment.

[0032] Figure 8 This is an explanatory diagram of the manufacturing process of the stamped product according to the first embodiment.

[0033] Figure 9 This is an explanatory diagram of the manufacturing process of the stamped product according to the first embodiment.

[0034] Figure 10A It is a graph showing the relationship between the position of the protrusion of the second die and the pin height of the stamped product in the stamping process according to the first embodiment.

[0035] Figure 10B This is an explanatory diagram used to illustrate the conditions for analysis.

[0036] Figure 11 This is a diagram of the punch in the stamping apparatus of the first modified example, viewed from the direction of punch movement.

[0037] Figure 12 This is a diagram of the punch in the stamping apparatus of the second modified example, viewed from the direction of punch movement.

[0038] Figure 13 This is a diagram of the punch in the stamping apparatus of the third modified example, viewed from the direction of punch movement.

[0039] Figure 14 This is a cross-sectional view of the stamped product according to the second embodiment.

[0040] Figure 15 yes Figure 14 The XV direction view.

[0041] Figure 16 yes Figure 14 The XVI direction view.

[0042] Figure 17 yes Figure 14 An enlarged view of the XVII section.

[0043] Figure 18 This is an explanatory diagram of the manufacturing process of the stamped product according to the second embodiment.

[0044] Figure 19 This is an explanatory diagram of the manufacturing process of the stamped product according to the second embodiment.

[0045] Figure 20 This is an explanatory diagram of the manufacturing process of the stamped product according to the second embodiment.

[0046] Figure 21 This is an explanatory diagram of the manufacturing process of the stamped product according to the second embodiment.

[0047] Figure 22 This is a cross-sectional view of the stamped product according to the third embodiment.

[0048] Figure 23 yes Figure 22 A view in the XXIII direction.

[0049] Figure 24 yes Figure 22 A view in the XXIV direction.

[0050] Figure 25 This is a cross-sectional view of the stamped product of the first comparative example.

[0051] Figure 26 yes Figure 25 The view in the XXVI direction.

[0052] Figure 27 yes Figure 25 A view in the direction of XXVII.

[0053] Figure 28 This is an explanatory diagram of the manufacturing process of the stamped product of the first comparative example.

[0054] Figure 29 This is an explanatory diagram of the manufacturing process of the stamped product of the first comparative example.

[0055] Figure 30 This is an explanatory diagram of the manufacturing process of the stamped product of the first comparative example.

[0056] Figure 31 This is an explanatory diagram of the manufacturing process of the stamped product of the first comparative example.

[0057] Figure 32 This is a cross-sectional view of the stamped product of the second comparative example.

[0058] Figure 33 yes Figure 32 View in the XXXIII direction.

[0059] Figure 34 yes Figure 32 A view in the XXXIV direction.

[0060] Figure 35 This is an explanatory diagram of the manufacturing process of the stamped product of the second comparative example.

[0061] Figure 36 This is an explanatory diagram of the manufacturing process of the stamped product of the second comparative example.

[0062] Figure 37 This is an explanatory diagram of the manufacturing process of the stamped product of the second comparative example.

[0063] Figure 38 This is an explanatory diagram of the manufacturing process of the stamped product of the second comparative example. Detailed Implementation

[0064] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, for parts that are the same or equivalent to each other in the following embodiments, the same reference numerals will be used and their descriptions will be omitted.

[0065] (First Implementation)

[0066] The stamped product, stamping apparatus, and stamping method of the first embodiment will be described with reference to the accompanying drawings. Furthermore, the shapes of the stamped product and stamping apparatus described in the first embodiment are merely examples and are not limited to that shape. This also applies to the second and third embodiments described later.

[0067] <Structure of stamped products>

[0068] First, the structure of the stamped product 1 according to the first embodiment will be described. This stamped product 1 is manufactured by extrusion using a stamping apparatus. This stamped product 1 can also be referred to as a plastic-finished product or a cold-forged product.

[0069] like Figures 1-3 As shown, the stamped product 1 of the first embodiment includes a main body 2, a recess 3, a pin 4 and a groove 5, and is integrally formed by metal.

[0070] The main body 2 is a plate-shaped component. The surface of the main body 2 facing its thickness direction is referred to as the first surface 21, and the surface of the main body 2 facing the thickness direction is referred to as the second surface 22. That is, the side opposite to the first surface 21 of the main body 2 is the second surface 22. A recess 3 is provided on the first surface 21 side of the main body 2, and a pin 4 and a groove 5 are provided on the second surface 22 side of the main body 2.

[0071] The recess 3 is a portion that is recessed from the first surface 21 of the main body 2 toward the second surface 22. The recess 3 is formed, for example, in a cylindrical shape. In the state viewed from the thickness direction of the main body 2 (hereinafter referred to as "thickness direction view of the main body 2"), the shape and size of the recess 3 are formed to be larger than the shape and size of the pin 4.

[0072] Pin 4 protrudes from the second surface 22 of the main body 2 in the thickness direction of the main body 2. Pin 4 is positioned corresponding to the recess 3. Specifically, the axis CL1 of pin 4 may be almost at the same position as the center of the recess 3, or it may be slightly offset from the center of the recess 3. Pin 4 is, for example, shaped as a cylinder, with the outer periphery 41 of its top portion being chamfered. In the thickness direction view of the main body 2, the shape of pin 4 is shaped to be smaller than the shape of the recess 3. The axis CL1 of pin 4 is shaped perpendicular to the second surface 22.

[0073] The groove 5 is a groove that is recessed from the second surface 22 of the main body 2 toward the first surface 21 and surrounds at least a portion of the periphery of the pin 4. In the first embodiment, the groove 5 surrounds the entire circumference of the pin 4. Furthermore, the position where the groove 5 is provided is set in a range that is outside the inscribed circle of the shape of the recess 3 in the thickness direction view relative to the main body 2 and inside the position that is a distance equal to the radius of the circumscribed circle of the shape of the recess 3 plus 1.5 times the thickness T of the main body 2. The reason for this will be described below. In addition, in the first embodiment, since the recess 3 is formed into a cylindrical shape, the inscribed circle and the circumscribed circle of the recess 3 are the same.

[0074] like Figure 1 and Figure 4 As shown in the cross-sectional view parallel to the thickness direction of the main body 2, the groove 5 has tapered inner wall surfaces 51 and 52 whose width gradually decreases from the second surface 22 toward the first surface 21. The tapered angle θ1 is in the range of 40° to 80°, more preferably in the range of 55° to 65°. Furthermore, the depth H1 of the groove 5 is in the range of 2% to 20% relative to the thickness T of the main body 2, more preferably in the range of 8% to 15%.

[0075] Furthermore, in a cross-sectional view parallel to the thickness direction of the main body 2, the distance D1 between the recess 3 and the groove 5 is greater than the distance D2 between the recess 3 and the second surface 22. Therefore, by preventing the wall thickness of the main body 2 from being minimized between the recess 3 and the groove 5, the strength of the stamped product 1 can be guaranteed.

[0076] <Structure of stamping equipment>

[0077] Next, refer to Figure 9 The stamping apparatus used to manufacture the stamped workpiece 1 of the first embodiment will be described.

[0078] like Figure 9 As shown, the stamping processing apparatus 8 includes a first mold 80 disposed on the first surface 21 side of the main body portion 2 of the stamped workpiece 1 and a second mold 90 disposed on the second surface 22 side of the main body portion 2.

[0079] The first mold 80 has a punch 81 and a demolding device 82.

[0080] The punch 81 is a movable die that forms the recess 3 on the first surface 21 of the main body 2. In the first embodiment, the punch 81 is cylindrical. In the thickness direction view of the main body 2 (i.e., the state viewed from the direction of movement of the first die 80), the shape and size of the punch 81 are formed to be larger than the shape and size of the hole 92 of the second die 90. The ejector 82 is a movable die that surrounds the punch 81 on the outside and is capable of pressing the first surface 21 of the main body 2. The punch 81 and the ejector 82 can be moved independently by a drive device (not shown).

[0081] The second mold 90 has a base 91, a hole 92, and a protrusion 93. The second mold 90 is called a punch.

[0082] The base 91 is a portion having a surface 911 that contacts the second surface 22 of the stamped workpiece 1. This surface 911 is a planar surface in the base 91 facing the side of the first mold 80.

[0083] Hole 92 is a through hole for forming the pin 4 of the stamped part 1, and is provided at a position corresponding to the punch 81. Hole 92 is formed, for example, into a cylindrical shape, and a chamfered tapered portion 921 for forming the tip of the pin 4 is provided midway along the inner wall of this cylindrical shape. The tapered portion 921 has a larger diameter at the punch 81 side, and the diameter gradually decreases towards the depth. Furthermore, the inner diameter of hole 92 is the same from the entrance side (i.e., the punch 81 side) to the larger diameter side of tapered portion 921. In the thickness direction view of the main body 2, the outer shape of hole 92 is formed to be smaller than the outer shape of punch 81. The axis CL2 of hole 92 is formed perpendicularly to the surface 911 of base 91 facing the first die 80 side. In addition, the axis CL2 of hole 92 is formed parallel to the moving direction of the first die 80 (i.e., the thickness direction of the main body 2).

[0084] The protrusion 93 is the portion of the groove 5 forming the stamped workpiece 1, and protrudes from the base 91 toward the first die 80 side, surrounding at least a portion of the periphery of the hole 92. In the first embodiment, the protrusion 93 surrounds the entire circumference of the hole 92. The position where the protrusion 93 is provided is set in a range that is outside the inscribed circle of the shape of the punch 81 in the thickness direction view relative to the main body 2, and inside the position that is a distance equal to the radius of the circumscribed circle of the shape of the punch 81 plus 1.5 times the thickness T of the main body 2. The reason for this will be described below. Furthermore, in the first embodiment, since the punch 81 is formed into a cylindrical shape, the inscribed circle and the circumscribed circle of the punch 81 are the same.

[0085] In a cross-sectional view parallel to the thickness direction of the main body 2, the protrusion 93 has tapered outer wall surfaces 94 and 95 whose width gradually decreases from the base 91 toward the first mold 80. Its cone angle θ2 is in the range of 40° to 80°, more preferably in the range of 55° to 65°. Furthermore, the height H2 of the protrusion 93 is in the range of 2% to 20% of the thickness T of the main body 2, more preferably in the range of 8% to 15%. The thickness T of the main body 2 is consistent with the distance between the demolding device 82 and the second mold 90 when the demolding device 82 is closest to the second mold 90. Furthermore, as... Figure 8 and Figure 10B As shown, when the punch 81 and the ejector 82 are closest to the second mold 90, the distance between the punch 81 and the protrusion 93 is greater than the distance between the punch 81 and the base 91.

[0086] <Stamping Processing Methods>

[0087] Next, refer to Figure 5 Flowcharts and Figures 6-9 The explanatory diagram illustrates the method of manufacturing a stamped product 1 using the stamping apparatus 8 of the first embodiment.

[0088] First of all, Figure 5 In step S10, a stamping processing device 8 equipped with the first mold 80 and the second mold 90 described above is prepared.

[0089] First, in step S20, the part to be processed 20 is arranged between the first mold 80 and the second mold 90. Figure 6 This indicates the state. For example... Figure 6 As shown, the workpiece 20 disposed between the first mold 80 and the second mold 90 corresponds to the main body 2 of the stamped workpiece 1. The thickness of the workpiece 20 is the same as the thickness T of the main body 2 of the stamped workpiece 1.

[0090] Next, in Figure 5 In step S30, the demolding device 82 of the first mold 80 is moved toward the second mold 90 side, and the protrusion 93 is pressed into the workpiece 20. Figure 7 This indicates the state. For example... Figure 7 As shown, the workpiece 20 is pressed towards the second mold 90 by the pressing force of the demolding device 82, and the protrusion 93 of the second mold 90 is pressed into the workpiece 20. As a result, a groove 5 is formed on the second surface 22 of the main body 2 of the stamped workpiece 1. Furthermore, in Figure 7 Although the text shows that the groove 5 is entirely formed on the second surface 22 of the main body 2, this is only one example. In step S30, at least a portion of the groove 5 may be formed on the second surface 22 of the main body 2.

[0091] Next, in Figure 5 In step S40, the punch 81 is driven into the workpiece 20 to form the pin 4 on the opposite side. Figure 8 This indicates the state. For example... Figure 8 As indicated by arrow F1, when the punch 81 moves towards the second die 90 and strikes the main body 2 of the workpiece 20, thereby forming the recess 3 on the first surface 21 of the stamped workpiece 1, the material of the workpiece 20 flows and forms the pin 4 on the second surface 22. At this time, as indicated by arrow F2, the protrusion 93 of the second die 90 prevents the material of the workpiece 20 from flowing towards the surface of the second surface 22 due to the pressing force of the punch 81. Therefore, as indicated by arrow F3, the pushing force of the material of the workpiece 20 pressed into the hole 92 of the second die 90 increases. Therefore, even when the frictional resistance between the material of the workpiece 20 pressed into the inner side of the hole 92 and the inner wall of the hole 92 is large, the pin 4 can be formed higher. Furthermore, since the hole 92 has the same inner diameter from the inlet side (i.e., the punch 81 side) across the large diameter side of the tapered portion 921, the straightness of the pin 4 can be ensured. Furthermore, in step S30 above, if a portion of the groove 5 is formed on the second surface 22 of the main body 2, in step S40, while the punch 81 is being driven in, the demolding device 82 is moved further toward the second mold 90 side and the groove 5 is formed on the second surface 22 of the main body 2 by the protrusion 93.

[0092] Subsequently, Figure 5 In step S50, the demolding device 82 and the punch 81 are moved away from the second mold 90, and the stamped workpiece 1 is taken out from between the first mold 80 and the second mold 90. Figure 9 This indicates the current state. Subsequently, finishing processes are performed to complete stamped part 1.

[0093] The pin 4 of the stamped part 1 is used when it is riveted to other parts (not shown). In the process of riveting the stamped part 1 to other parts, after inserting the pin 4 into a hole in the other part, a load is applied to the tip of the pin 4, causing the tip to deform. Thus, the stamped part 1 is riveted to the other parts. At this time, because the pin 4 of the stamped part 1 is formed relatively high, the strength of the riveting connection is high.

[0094] <First Comparative Example>

[0095] Here, in order to compare with the first embodiment described above, the stamped workpiece 101, the stamping apparatus 801, and the stamping method of the first comparative example will be described.

[0096] like Figures 25-27 As shown, the stamped product 101 of the first comparative example has a main body 2, a recess 3, and a pin 4. However, the stamped product 101 of the first comparative example does not have a groove 5.

[0097] Figure 31 This refers to the stamping apparatus 801 that manufactures the stamped workpiece 101 of the first comparative example.

[0098] like Figure 31 As shown, the stamping apparatus 801 of the first comparative example also includes: a first die 80 having a punch 81 and a ejector 82; and a second die 90 having a base 91 and a hole 92. However, the second die 90 of the stamping apparatus 801 of the first comparative example does not have a protrusion 93.

[0099] Reference Figures 28-31 The stamping process performed by the stamping apparatus 801 of the first comparative example will be described.

[0100] First, such as Figure 28 As shown, a stamping processing apparatus 801 is prepared having a first mold 80 and a second mold 90, and a workpiece 20 is disposed between the first mold 80 and the second mold 90.

[0101] Next, as Figure 29 As shown, the first mold 80 is moved toward the second mold 90.

[0102] Next, as Figure 30As indicated by arrow F4, the punch 81 is driven into the workpiece 20 to form a recess 3 on the first surface 21, and a pin 4 is formed on the opposite side. At this time, in the stamping apparatus 801 of the first comparative example, as indicated by arrow F5, by the pressing force of the punch 81, most of the material of the main body 2 of the workpiece 20 flows towards the surface of the second surface 22. Therefore, as indicated by arrow F6, the pushing force of the material of the workpiece 20 pressed into the hole 92 of the second die 90 is reduced. Furthermore, in the first comparative example, since the hole 92 also has the same inner diameter across the large diameter side of the tapered portion 921 from the entrance side, the frictional resistance between the material of the workpiece 20 pressed into the inner side of the hole 92 and the inner wall of the hole 92 is large. Therefore, in the first comparative example, the material of the workpiece 20 cannot fully enter the hole 92 of the second die 90, and the pin 4 is formed too low.

[0103] Subsequently, as Figure 31 As shown, the stamped product 101 of the first comparative example is taken out from between the first mold 80 and the second mold 90.

[0104] Furthermore, when the stamped part 101 of the first comparative example is riveted together with other parts, there is a concern that the strength of the riveting joint may be weakened because the pin 4 is formed lower in the stamped part 101 of the first comparative example compared with the structure of the first embodiment.

[0105] <Relationship between the position of the protrusion in the mold and the height of the pin>

[0106] Next, regarding the stamping apparatus 8 and the stamped product 1, refer to... Figure 10A The curve and Figure 10B The explanatory diagram illustrates the results of analyzing the relationship between the position of the protrusion 93 of the second mold 90 and the height of the pin 4. Furthermore, Figure 10B This is an explanatory diagram used to represent the conditions for parsing.

[0107] Figure 10A The horizontal axis of the graph represents the distance D3 between the center CL1 of pin 4 (i.e., the center CL2 of the hole 92 of the second mold 90) and the center of the protrusion 93 of the second mold 90. Additionally, the vertical axis on the left side of the graph represents the surface pressure, and the vertical axis on the right side represents the height H3 of pin 4.

[0108] In this analysis, the plate thickness T of the main body 2 of the stamped workpiece 1 (i.e., the plate thickness of the workpiece 20) is set to 4.2 mm, the radius D4 of the punch 81 is set to 2.75 mm (i.e., the diameter of the punch 81 is set to 5.5 mm), the radius D5 of the pin 4 is set to 1.5 mm (i.e., the diameter of the pin 4 is set to 3 mm), and the height H2 of the protrusion 93 is set to 0.5 mm.

[0109] Figure 10A In the graph, the solid line A represents the height H3 of pin 4, the dashed line B represents the surface pressure acting on the inlet 922 of hole 92 (i.e., the root of pin 4) during stamping, and the single-dot dashed line C represents the surface pressure acting on protrusion 93 during stamping.

[0110] also, Figure 10A The point Y at the right end of the solid line A and the point Z at the right end of the dashed line B shown in the right frame X of the graph represent the structure in which the protrusion 93 of the second mold 90 is absent, similar to the first comparative example (i.e., the stamped product 101 does not have the groove 5).

[0111] As shown by solid line A, the height H3 of pin 4 elongates when the second mold 90 has protrusion 93, and the distance D3 between the axis CL1 of pin 4 and the center of protrusion 93 of the second mold 90 increases more sharply as it gets closer to 6mm.

[0112] As shown by dashed line B, the surface pressure acting on the inlet 922 of the hole 92 during the stamping process is almost constant.

[0113] As shown by the single-dot dashed line C, the surface pressure acting on the protrusion 93 during stamping increases as the distance D3 between the axis CL1 of pin 4 and the center of the protrusion 93 of the second mold 90 approaches 5mm.

[0114] Furthermore, when the distance D3 between the center of the shaft CL1 of pin 4 and the center of the protrusion 93 of the second mold 90 is less than 3mm, all values ​​decrease compared to 3.5mm.

[0115] like Figure 10A As shown by solid line A, at point P on the horizontal axis, the height H3 of pin 4 is more than 15% higher than the height H3 of pin 4 shown at point Y on the right end of solid line A (shown in right frame X). If the height H3 of pin 4 in stamped part 1 is more than 15% higher than the structure of the first comparative example, sufficient riveting strength is obtained when stamped part 1 is riveted to other parts. Therefore, it is preferable that the distance D3 between the axis CL1 of pin 4 and the center of the protrusion 93 of the second die 90 is set close to the axis CL1 of pin 4 compared to point P on the horizontal axis. Point P on the horizontal axis is located at a distance equal to the radius of the circumscribed circle of punch 81 plus 1.5 times the thickness T of the main body 2. Specifically, in the example shown in this analysis, at point P, the distance D3 between the axis CL1 of pin 4 and the center of the protrusion 93 of the second die 90 is 8.75 mm.

[0116] On the other hand, at point Q shown on the horizontal axis, the height H3 of pin 4 is approximately 25% higher than the height H3 of pin 4 shown at point Y, the right end of the solid line A shown in the right frame X. However, there is a tendency for pin 4 to decrease if the protrusion 93 is closer to the axis CL1 of pin 4. Therefore, it is preferable that the distance D3 between the axis CL1 of pin 4 and the center of the protrusion 93 of the second mold 90 is set at a position far from the axis CL1 of pin 4 compared to point Q shown on the horizontal axis. This point Q on the horizontal axis is a position that coincides with the radius of the inscribed circle of punch 81. Specifically, in the example shown in this analysis, at point Q, the distance D3 between the axis CL1 of pin 4 and the center of the protrusion 93 of the second mold 90 is 2.75 mm.

[0117] As described above, in the stamping apparatus 8, the position where the protrusion 93 is provided is set to be outside the inscribed circle of the shape of the punch 81 in the thickness direction view relative to the main body 2, and inside the position at a distance that is 1.5 times the radius of the circumscribed circle of the shape of the punch 81 plus the thickness T of the main body 2.

[0118] That is, in the stamped product 1, the position where the groove 5 is provided is set in a range that is outside the inscribed circle of the shape of the recess 3 in the thickness direction view relative to the main body 2 and inside the position that is 1.5 times the radius of the circumscribed circle of the shape of the recess 3 plus the thickness T of the main body 2.

[0119] Here, the inscribed and circumscribed circles of the shapes of the recess 3 and the punch 81 will be explained.

[0120] As described above, the shapes of the various parts of the stamped workpiece 1 and the stamping apparatus 8 in the first embodiment are only examples and are not limited to this structure. That is, the shape of the recess 3 of the stamped workpiece 1 and the shape of the punch 81 of the stamping apparatus 8 are not limited to cylindrical shapes, and various shapes can be considered.

[0121] Figures 11-13 This illustrates a variation of the shape of the punch 81 included in the stamping apparatus 8 described in the first embodiment. Figures 11-13 The figure shows the shape of the punch 81 in the stamping apparatus 8 as viewed from the direction of movement of the punch 81. Furthermore, the direction of movement of the punch 81 is the same as the thickness direction of the main body 2.

[0122] like Figure 11 As shown, in the first modified example, the punch 81 is formed into a quadrilateral. (As...) Figure 12 As shown, in the second variation, the punch 81 is formed into an elliptical shape. (As illustrated...) Figure 13 As shown, in the third variation, the punch 81 is roughly in the shape of a plus sign, formed by four circular arcs recessed towards the center and four straight lines connecting the ends of the four circular arcs to each other.

[0123] exist Figures 11-13 In the diagram, the inscribed circle of the shape of the punch 81 as viewed from the direction of movement is represented by a single-dotted line C1, and the circumscribed circle of the shape of the punch 81 is represented by a single-dotted line C2. Thus, the shape of the punch 81 is not limited to a circle, and even in the case of various shapes, the position of the protrusion 93 of the stamping device 8 can be set based on the inscribed circle and the circumscribed circle of that shape.

[0124] Furthermore, since the shape of the recess 3 of the stamped workpiece 1 corresponds to the shape of the punch 81 of the stamping device 8, the same consideration can be made. That is, the shape of the recess 3 of the stamped workpiece 1 is not limited to a circle, and even in the case of various shapes, the position for setting the groove 5 of the stamped workpiece 1 can be set based on the inscribed circle and the circumscribed circle of the shape.

[0125] <Effects of the First Embodiment>

[0126] The stamped product 1, stamping apparatus 8, and stamping method described above in the first embodiment have the following effects.

[0127] (1) The stamped workpiece 1 of the first embodiment has a groove 5 on the second surface 22 side of the main body 2, which is configured to surround at least a portion of the area around the pin 4.

[0128] When manufacturing a stamped part 1 of this shape by stamping, a first mold 80 and a second mold 90 are prepared. The first mold 80 has a punch 81 and a ejector 82, and the second mold 90 has a hole 92 and a protrusion 93. Then, a main body 2 serving as the workpiece 20 is provided between the first mold 80 and the second mold 90. By striking the first surface 21 of the main body 2 with the punch 81, material is pressed out from the hole 92, forming a pin 4 on the second surface 22 side. At this time, since the material of the main body 2 is blocked from flowing towards the surface of the second surface 22 by the pressing force of the punch 81 by the protrusion 93 of the second mold 90, the pushing force of the material of the main body 2 pressed out towards the hole 92 of the second mold 90 increases. Therefore, when the stamped part 1 of this shape is manufactured by stamping, the straightness of the pin 4 can be ensured, and the pin 4 can be formed to a higher position.

[0129] (2) In the stamped product 1 of the first embodiment, the position of the groove 5 is located outside the inscribed circle of the shape of the recess 3 in the thickness direction view relative to the main body 2 and inside the position of the groove 5. The distance is the radius of the circumscribed circle of the shape of the recess 3 plus 1.5 times the thickness T of the main body 2.

[0130] Therefore, compared to the structure of the stamped product 101 of the first comparative example, which lacks the groove 5, the stamped product 1 of the first embodiment can ensure the straightness of the pin 4 and can form the pin 4 at a higher height. Specifically, according to the inventor's analysis and experiments, the height H3 of the pin 4 of the stamped product 1 of the first embodiment can be formed to be more than 15% higher than that of the stamped product 101 of the first comparative example.

[0131] (3) The depth H1 of the groove 5 of the stamped work 1 of the first embodiment is in the range of 2% to 20% relative to the plate thickness T of the main body 2, and more preferably in the range of 8% to 15%.

[0132] Therefore, when manufacturing the stamped product 1, the protrusion 93 of the second mold 90 effectively blocks the material of the main body 2 from flowing toward the surface of the second surface 22 due to the pressing pressure of the punch 81, thereby increasing the pushing force of the material of the main body 2 being pressed out toward the hole 92 of the second mold 90.

[0133] (4) The groove 5 of the stamped product 1 of the first embodiment has conical inner wall surfaces 51 and 52, the width of which gradually decreases from the second surface 22 toward the first surface 21 in a cross-sectional view parallel to the thickness direction of the main body 2.

[0134] Therefore, when manufacturing the stamped product 1, by providing the main body 2 between the first mold 80 and the second mold 90 and pressing the demolding device 82 against the first surface 21 side of the main body 2, the protrusion 93 of the second mold 90 can be easily and reliably pressed into the second surface 22 of the main body 2.

[0135] (5) In a cross-sectional view of the stamped product 1 of the first embodiment, parallel to the thickness direction of the main body 2, the distance D1 between the recess 3 and the groove 5 is greater than the distance D2 between the recess 3 and the second surface 22.

[0136] Therefore, since the wall thickness of the main body 2 can be prevented from being at its minimum between the recess 3 and the groove 5, the strength of the stamped product 1 can be guaranteed.

[0137] (6) The first mold 80 of the stamping apparatus 8 of the first embodiment includes: a punch 81, which forms a recess 3 on the first surface 21 of the main body 2; and a demolding device 82, which presses the first surface 21 on the outside of the punch 81. The second mold 90 includes: a hole 92, which is provided at a position corresponding to the punch 81 and forms a pin 4 on the second surface 22 side; and a protrusion 93, which protrudes from the base 91 toward the first mold 80 side and is configured to surround at least a portion of the hole 92, and forms a groove 5 on the second surface 22 side.

[0138] Therefore, when the stamped part 1 is manufactured by the stamping apparatus 8, the protrusion 93 of the second die 90 prevents the material of the main body 2 of the workpiece 20 from flowing towards the surface of the second surface 22 due to the pressing pressure of the punch 81. As a result, the pushing force of the material of the main body 2 towards the hole 92 of the second die 90 increases. Therefore, the stamping apparatus 8 can ensure the straightness of the pin 4 formed in the stamped part 1 and can form the pin 4 at a higher elevation.

[0139] (7) In the stamping apparatus 8 of the first embodiment, the position of the protrusion 93 of the second mold 90 is located outside the inscribed circle of the shape of the punch 81 in the thickness direction view relative to the main body 2 and inside the position of the protrusion 93 of the second mold 90 is located at a distance of 1.5 times the radius of the circumscribed circle of the shape of the punch 81 plus the thickness T of the main body 2.

[0140] Because, compared to the stamping apparatus 801 of the first comparative example, which lacks the protrusion 93, the stamping apparatus 8 of the first embodiment can ensure the straightness of the pin 4 of the stamped product 1 and can form the pin 4 to a higher height. Specifically, according to the inventor's analysis and experiments, compared to the stamping apparatus 801 of the first comparative example, the stamping apparatus 8 of the first embodiment can form the height H3 of the pin 4 to be more than 15% higher.

[0141] (8) In the stamping apparatus 8 of the first embodiment, the height H2 of the protrusion 93 of the second die 90 is in the range of 2% to 20% relative to the plate thickness T of the main body 2, and more preferably in the range of 8% to 15%.

[0142] Therefore, during the stamping process, the protrusion 93 of the second die 90 effectively prevents the material of the main body 2 from flowing towards the surface of the second surface 22 due to the pressing pressure of the punch 81, thereby increasing the pushing force of the material of the main body 2 towards the hole 92 of the second die 90.

[0143] (9) In the stamping apparatus 8 of the first embodiment, the protrusion 93 of the second mold 90 has a tapered outer wall surface 94, 95 whose width gradually decreases from the base 91 toward the first mold 80 in a cross-sectional view parallel to the thickness direction of the main body 2.

[0144] Therefore, when performing stamping, a main body 2 is provided between the first mold 80 and the second mold 90. By pressing the demolding device against the first surface 21 side of the main body 2, the protrusion 93 of the second mold 90 can be easily and reliably pressed into the second surface 22 of the main body 2.

[0145] (10) In the stamping process of the first embodiment, when the punch 81 is closest to the base 91 during stamping, the distance between the punch 81 and the protrusion 93 is greater than the distance between the punch 81 and the base 91.

[0146] Therefore, in the stamped product 1 manufactured by the stamping processing device 8, the strength of the stamped product 1 can be guaranteed because the wall thickness of the main body 2 is prevented from being at its minimum between the recess 3 and the groove 5.

[0147] (11) In the stamping method of the first embodiment, the main body 2 of the stamped workpiece 1, which serves as the workpiece 20, is disposed between the first mold 80 and the second mold 90 provided in the stamping apparatus 8. Then, the ejector 82 is moved toward the second mold 90 side, and at least a portion of the groove 5 is formed on the second surface 22 by the protrusion 93. Subsequently, the ejector 82 is moved further toward the second mold 90 side, and the groove 5 is formed on the second surface 22 by the protrusion 93. The punch 81 is moved toward the second mold 90 side, and a recess 3 is formed on the first surface 21, and a pin 4 is formed through the hole 92. Next, the first mold 80 is moved away from the second mold 90, and the stamped workpiece 1 is taken out from between the first mold 80 and the second mold 90.

[0148] According to this stamping method, when the punch 81 is inserted into the material of the main body 2, the protrusion 93, which has formed the groove 5 in the previous process, blocks the material of the main body 2 from flowing towards the surface of the second surface 22 by the pressing force of the punch 81. Therefore, the pushing force of the material of the main body 2 towards the hole 92 of the second die 90 is increased. Therefore, according to this stamping method, the straightness of the pin 4 formed in the stamped product 1 can be ensured, and the pin 4 can be formed at a higher height.

[0149] (Second Implementation)

[0150] The stamped product 1, stamping apparatus 8, and stamping method according to the second embodiment will be described. The stamped product 1 of the second embodiment adds a pedestal portion to the structure of the stamped product 1 of the first embodiment, while the other structures are the same as those of the first embodiment. Furthermore, the stamping apparatus 8 of the second embodiment adds a pedestal forming portion to the structure of the stamping apparatus 8 of the first embodiment, while the other structures are the same as those of the first embodiment.

[0151] <Structure of stamped products>

[0152] like Figures 14-16 As shown, the stamped product 1 has a main body 2, a recess 3, a pin 4, a base 6, and a groove 5, and is integrally formed by metal.

[0153] The main body 2 is a plate-shaped component. The surface of the main body 2 facing the thickness direction is called the first surface 21, and the other surface of the main body 2 facing the thickness direction is called the second surface 22. A recess 3 is provided on the first surface 21 side of the main body 2, and a pin 4, a base 6, and a groove 5 are provided on the second surface side of the main body 2.

[0154] The recess 3 is a portion that is recessed from the first surface 21 of the main body 2 toward the second surface 22. The recess 3 is formed, for example, in a cylindrical shape. In the thickness direction view of the main body 2, the shape and size of the recess 3 are formed to be the same as or larger than the shape and size of the pedestal 6.

[0155] Pin 4 protrudes from the second surface 22 of the main body 2 in the thickness direction of the main body 2. Pin 4 is positioned corresponding to the recess 3. Specifically, the axis CL1 of pin 4 may be almost at the same position as the center of the recess 3, or it may be slightly offset from the center of the recess 3. Pin 4 is, for example, shaped as a cylinder, with the outer periphery 41 of its top portion being chamfered. In the thickness direction view of the main body 2, the shape of pin 4 is smaller than the shape of the recess 3.

[0156] A pedestal portion 6 is disposed around the pin 4 and protrudes from the second surface 22 toward the thickness direction of the main body portion 2. The height at which the pedestal portion 6 protrudes from the second surface 22 is very small compared to the height at which the pin 4 protrudes from the second surface 22. In the thickness direction view of the main body portion 2, the shape and size of the pedestal portion 6 are formed to be the same as or smaller than the shape and size of the recess 3. The surface 61 of the pedestal portion 6 facing the thickness direction of the main body portion 2 is formed as a plane perpendicular to the axis CL1 of the pin 4. The surface 61 of the pedestal portion 6 facing the thickness direction of the main body portion 2 is the surface that abuts against other components (not shown) when the stamped product 1 of the second embodiment is riveted together.

[0157] The groove 5 is a recessed portion extending from the second surface 22 of the main body 2 towards the first surface 21, surrounding at least a portion of the periphery of the pin 4 and the base portion 6. In the second embodiment, the groove 5 is located on the outer side relative to the base portion 6 and the recess 3, surrounding the entire circumference of the pin 4 and the base portion 6. Furthermore, in the second embodiment, the position where the groove 5 is located is set to be on the outer side of the inscribed circle of the shape of the recess 3 in the thickness direction view relative to the main body 2, and on the inner side of a position that is a distance equal to the radius of the circumscribed circle of the shape of the recess 3 plus 1.5 times the thickness T of the main body 2. Thus, compared to the second comparative example described later, the pin 4 can be formed to be sufficiently high.

[0158] like Figure 14 and Figure 17As shown in the cross-sectional view parallel to the thickness direction of the main body 2, the groove 5 has tapered inner wall surfaces 51 and 52 whose width gradually decreases from the second surface 22 toward the first surface 21. The tapered angle θ1 is in the range of 40° to 80°, more preferably in the range of 55° to 65°. Furthermore, the depth H1 of the groove 5 is in the range of 2% to 20% relative to the thickness T of the main body 2, more preferably in the range of 8% to 15%.

[0159] Furthermore, in a cross-sectional view parallel to the thickness direction of the main body 2, the distance D1 between the recess 3 and the groove 5 is greater than the distance D2 between the recess 3 and the second surface 22. Therefore, by preventing the wall thickness of the main body 2 from being minimized between the recess 3 and the groove 5, the strength of the stamped product 1 can be guaranteed.

[0160] <Structure of stamping equipment>

[0161] Next, refer to Figure 21 The stamping apparatus 8 used to manufacture the stamped workpiece 1 of the second embodiment will be described.

[0162] like Figure 21 As shown, the stamping processing apparatus 8 includes a first mold 80 disposed on the first surface 21 side of the main body portion 2 of the stamped workpiece 1 and a second mold 90 disposed on the second surface 22 side of the main body portion 2.

[0163] The first mold 80 has a punch 81 and a demolding device 82.

[0164] The punch 81 is a movable mold that forms the recess 3 on the first surface 21 of the main body 2. In the second embodiment, the punch 81 is also cylindrical. In the thickness direction view of the main body 2 (i.e., the state viewed from the direction of movement of the first mold 80), the shape and size of the punch 81 are formed to be the same as, or larger than, the shape and size of the pedestal forming portion 96 of the second mold 90. The ejector 82 is a movable mold that surrounds the punch 81 on the outside and is capable of pressing the first surface 21 of the main body 2. The punch 81 and the ejector 82 can be moved independently by a drive device (not shown).

[0165] The second mold 90 has a base 91, a hole 92, a base forming part 96, and a protrusion 93. The second mold 90 is called a punch.

[0166] The base 91 is a portion having a surface 911 that contacts the second surface 22 of the stamped workpiece 1. This surface 911 is the surface of the base 91 facing the side of the first mold 80.

[0167] Hole 92 is a through hole for forming the pin 4 of the stamped part 1, and is provided at a position corresponding to the punch 81. Hole 92 is formed, for example, into a cylindrical shape, and a chamfered tapered portion 921 for forming the tip of the pin 4 is provided midway along the inner wall of this cylindrical shape. The tapered portion 921 has a larger diameter on the punch 81 side, and the diameter gradually decreases towards the depth. Furthermore, the inner diameter of hole 92 is the same from the entrance side (i.e., the punch 81 side) to the larger diameter side of tapered portion 921. In the thickness direction view of the main body 2, the outer shape of hole 92 is formed to be smaller than the outer shape of punch 81. The axis CL2 of hole 92 is formed perpendicularly to the surface of the forming part 96 facing the first die 80. In addition, the axis CL2 of hole 92 is formed parallel to the moving direction of the first die 80 (i.e., the thickness direction of the main body 2).

[0168] The pedestal forming portion 96 is a recessed shape of the pedestal portion 6 for forming the stamped workpiece 1, and is provided around the hole portion 92. The depth of the pedestal forming portion 96 is very small compared to the depth of the hole portion 92 from the inlet to the taper portion 921. In the thickness direction view of the main body portion 2, the shape and size of the pedestal forming portion 96 are formed to be the same as or smaller than the shape and size of the punch 81. The surface of the pedestal forming portion 96 facing the first die 80 is formed as a plane perpendicular to the axis CL2 of the hole portion 92.

[0169] The protrusion 93 is the portion of the groove 5 forming the stamped part 1, and protrudes from the base 91 toward the first die 80 side, surrounding at least a portion of the hole 92 and the pedestal forming part 96. In the second embodiment, the protrusion 93 surrounds the entire circumference of the hole 92 and the pedestal forming part 96. In the second embodiment, the position where the protrusion 93 is provided is also set to be outside the inscribed circle of the shape of the punch 81 in the thickness direction view relative to the main body 2, and inside the position at a distance that is 1.5 times the radius of the circumscribed circle of the shape of the punch 81 plus the thickness T of the main body 2. As a result, compared with the second comparative example described later, the pin 4 can be formed to be sufficiently high. Furthermore, since the punch 81 is also formed into a cylindrical shape in the second embodiment, the inscribed circle and the circumscribed circle of the punch 81 are the same.

[0170] The protrusion 93 has tapered outer wall surfaces 94 and 95, whose width gradually decreases from the base 91 toward the first mold 80 in a cross-sectional view parallel to the thickness direction of the main body 2. Its cone angle θ2 is in the range of 40° to 80°, more preferably in the range of 55° to 65°. Furthermore, the height H2 of the protrusion 93 is in the range of 2% to 20% relative to the thickness T of the main body 2, more preferably in the range of 8% to 15%. The thickness T of the main body 2 is consistent with the distance between the demolding device 82 and the second mold 90 when the demolding device 82 is closest to the second mold 90. Furthermore, as... Figure 20As shown, when the punch 81 and the ejector 82 are closest to the second mold 90, the distance between the punch 81 and the protrusion 93 is greater than the distance between the punch 81 and the base 91.

[0171] <Stamping Processing Methods>

[0172] Next, refer to Figures 18-21 The explanatory diagram illustrates the method of manufacturing stamped workpiece 1 using the stamping apparatus 8 of the second embodiment.

[0173] First, such as Figure 18 As shown, a stamping apparatus 8 is prepared, comprising the first mold 80 and the second mold 90 described above, and a workpiece 20 is disposed between the first mold 80 and the second mold 90. The workpiece 20 disposed between the first mold 80 and the second mold 90 corresponds to the main body 2 of the stamped workpiece 1. The thickness of the workpiece 20 is the same as the thickness T of the main body 2 of the stamped workpiece 1.

[0174] Next, as Figure 19 As shown, the ejector 82 of the first mold 80 moves toward the second mold 90, pressing the protrusion 93 into the workpiece 20. Through the pressing force of the ejector 82, the workpiece 20 is pressed toward the second mold 90, and the protrusion 93 of the second mold 90 is pressed into the workpiece 20. Thus, a groove 5 is formed on the second surface 22 of the main body 2 of the stamped workpiece 1.

[0175] Next, as Figure 20 As shown, the punch 81 is driven into the workpiece 20 to form a base portion 6 and a pin 4 on the opposite side. Figure 20 As indicated by arrow F7, when the punch 81 moves towards the second die 90 and strikes the main body 2 of the workpiece 20, thereby forming the recess 3 on the first surface 21 of the stamped workpiece 1, the workpiece 20 flows, forming the base portion 6 and the pin 4 on the second surface 22. At this time, as indicated by arrow F8, the protrusion 93 of the second die 90 prevents the material of the workpiece 20 from flowing towards the surface of the second surface 22 due to the pressing pressure of the punch 81. Therefore, as indicated by arrow F9, the pushing force of the material of the workpiece 20 pressed into the hole 92 of the second die 90 increases. Therefore, even when the frictional resistance between the material of the workpiece 20 pressed into the inner side of the hole 92 and the inner wall of the hole 92 is large, the pin 4 can be formed higher. Furthermore, since the hole 92 has the same inner diameter from the inlet side (i.e., the punch 81 side) across the large diameter side of the tapered portion 921, the straightness of the pin 4 can be ensured.

[0176] Subsequently, as Figure 21As shown, the ejector 82 and punch 81 are moved away from the second mold 90, and the stamped part 1 is taken out from between the first mold 80 and the second mold 90. Subsequently, finishing processes are performed to complete the stamped part 1.

[0177] The pin 4 of the stamped part 1 is used when it is riveted to other parts (not shown). In the process of riveting the stamped part 1 to other parts, the pin 4 of the stamped part 1 is inserted into a hole in the other part, causing the base portion 6 of the stamped part 1 to abut against the other part. Then, a load is applied to the tip of the pin 4, causing the tip of the pin 4 to deform. Thus, the stamped part 1 is riveted to other parts. At this time, because the pin 4 of the stamped part 1 is formed relatively high, the strength of the riveting connection is high.

[0178] <Second Comparative Example>

[0179] Here, in order to compare with the second embodiment described above, the stamped product 102, the stamping apparatus 802, and the stamping method of the second comparative example will be described.

[0180] like Figures 32-34 As shown, the stamped product 102 of the second comparative example includes a main body portion 2, a recess portion 3, a pin 4, and a base portion 6. However, the stamped product 102 of the second comparative example does not include a groove portion 5.

[0181] Figure 38 The stamping apparatus 802 represents the stamping process apparatus 102 used to manufacture the stamped product 102 of the second comparative example.

[0182] like Figure 38 As shown, the stamping apparatus 802 of the second comparative example also includes: a first mold 80 having a punch 81 and a ejector 82; and a second mold 90 having a base 91, a hole 92, and a base forming portion 96. However, the second mold 90 of the stamping apparatus 802 of the second comparative example does not have a protrusion 93.

[0183] Reference Figures 35-38 The stamping process performed by the stamping apparatus 802 of the second comparative example will be described.

[0184] First, such as Figure 35 As shown, a stamping processing apparatus 802 is prepared having a first mold 80 and a second mold 90, and a workpiece 20 is disposed between the first mold 80 and the second mold 90.

[0185] Next, as Figure 36 As shown, the first mold 80 is moved toward the second mold 90.

[0186] Next, as Figure 37As indicated by arrow F10, the punch 81 is driven into the workpiece 20 to form a recess 3 on the first surface 21, and a base portion 6 and a pin 4 are formed on the opposite side. At this time, in the stamping apparatus 802 of the second comparative example, as indicated by arrow F11, by the pressing force of the punch 81, most of the material of the main body portion 2 of the workpiece 20 flows towards the surface of the second surface 22. Therefore, as indicated by arrow F12, the pushing force of the material of the workpiece 20 pressed into the hole 92 of the second die 90 is reduced. Furthermore, in the second comparative example, since the hole 92 also has the same inner diameter across the large diameter side of the tapered portion 921 from the entrance side, the frictional resistance between the material of the workpiece 20 pressed into the inner side of the hole 92 and the inner wall of the hole 92 is large. Therefore, in the second comparative example, the material of the workpiece 20 cannot fully enter the hole 92 of the second die 90, and the pin 4 is formed too low.

[0187] Subsequently, as Figure 38 As shown, the stamped product 102 of the second comparative example is taken out from between the first mold 80 and the second mold 90.

[0188] Furthermore, when the stamped part 102 of the second comparative example is riveted together with other parts, there is a concern that the strength of the riveting joint is weakened because the pin 4 is formed lower in the stamped part 102 of the second comparative example compared with the structure of the second embodiment.

[0189] <Effects of the Second Embodiment>

[0190] The stamped product 1, stamping apparatus 8, and stamping method of the first embodiment described above, through the same structure as the first embodiment, achieve the same effects as the first embodiment. The stamped product 1 and stamping apparatus 8 of the second embodiment also achieve the following effects.

[0191] (1) The stamped product 1 according to the second embodiment includes a pedestal portion 6, which is disposed around the pin 4 on the second surface 22 side of the main body portion 2. The pedestal portion 6 has a surface 61 perpendicular to the axis CL1 of the pin 4. Furthermore, the shape and size of the recess 3 in the thickness direction view of the main body portion 2 are the same as or larger than the shape and size of the pedestal portion 6. The groove portion 5 is configured to surround at least a portion of the pin 4 and the pedestal portion 6.

[0192] Therefore, when the stamped workpiece 1 has a base portion 6 around the pin 4, the shape and size of the recess 3 formed by the punch 81 are set to be the same as or larger than the shape and size of the base portion 6. Thus, when manufacturing the stamped workpiece 1, the rate of reduction of the volume of material pressed into the hole 92 of the forming pin 4 relative to the volume of material pressed into the punch 81 increases. However, even in this case, since the protrusion 93 of the second die 90 also prevents the material of the main body 2 from flowing towards the surface of the second surface 22 due to the pressing force of the punch 81, the pushing force of the material of the main body 2 pressed into the hole 92 of the second die 90 increases. Therefore, the stamping apparatus 8 can ensure the straightness of the pin 4 formed in the stamped workpiece 1 and can form the pin 4 at a higher elevation.

[0193] (2) The second die 90 of the stamping apparatus 8 of the second embodiment has a pedestal forming portion 96 around the hole 92. The pedestal forming portion 96 is formed on the second surface 22 side of the main body 2. The pedestal portion 6 has a surface 61 perpendicular to the axis CL1 of the pin 4. Furthermore, the shape and size of the punch 81 in the thickness direction view of the main body 2 are the same as or larger than the shape and size of the pedestal forming portion 96. The protrusion 93 is provided to surround at least a portion of the hole 92 and the pedestal forming portion 96.

[0194] Therefore, when the second die 90 has a pedestal forming portion 96 around the hole 92, the punch 81 appears larger than the hole 92 in the thickness direction view of the main body 2. Consequently, when manufacturing the stamped product 1, the rate of reduction of the volume of material pressed into the hole 92 of the forming pin 4 relative to the volume of material pressed out by the punch 81 increases. However, even in this case, since the protrusion 93 of the second die 90 also prevents the material of the main body 2 from flowing towards the surface of the second surface 22 due to the pressing force of the punch 81, the pushing force of the material of the main body 2 pressed into the hole 92 of the second die 90 increases. Therefore, the stamping apparatus 8 can ensure the straightness of the pin 4 formed in the stamped product 1 and can form the pin 4 at a higher elevation.

[0195] (Third Implementation)

[0196] The stamped product 1 according to the third embodiment will be described. The third embodiment is a variation of the second embodiment.

[0197] like Figures 22-24 As shown, in the third embodiment, the stamped product 1 has a pin 4 near the outer edge 23 of the main body 2. Figures 22-24The example illustrates a structure in which a pin 4 is provided at the outer edge 23 near the right side of the main body 2. In this case, the groove 5 is configured to be slightly spaced from the outer edge 23 of the main body 2 and surround the pin 4. Specifically, in the thickness direction view of the main body 2, the groove 5 is shaped like a C and is configured to surround the pin 4 except for the side of the pin 4 near the outer edge.

[0198] Furthermore, in the third embodiment, the position where the groove 5 is provided is set to be located outside the inscribed circle of the shape of the recess 3 in the thickness direction view relative to the main body 2, and inside the position at a distance that is 1.5 times the radius of the circumscribed circle of the shape of the recess 3 plus the thickness T of the main body 2. In addition, the depth H1 of the groove 5 is in the range of 2% to 20% relative to the thickness T of the main body 2, and more preferably in the range of 8% to 15%.

[0199] Furthermore, in the third embodiment, the pedestal portion 6 is shaped as an ellipse in the thickness direction view of the main body portion 2.

[0200] The stamped product 1 of the third embodiment described above has the same structure as the first and second embodiments, and achieves the same effect as the first and second embodiments.

[0201] Furthermore, although the illustration is omitted, as a variation of the first embodiment, when the pin 4 is disposed near the outer edge 23 of the main body 2, as described in the third embodiment above, the groove 5 can be configured to be slightly spaced from the outer edge 23 of the main body 2 and surround the area around the pin 4.

[0202] (Other implementation methods)

[0203] (1) In the first to third embodiments described above, although the shape of the main body 2 in the thickness direction view of the stamped work 1 is quadrilateral, it is not limited to this. The shape of the main body 2 may be a circle, an ellipse or a polygon or various other shapes.

[0204] (2) In the first and second embodiments described above, although the recess 3, pin 4 and base 6 in the thickness direction view of the main body 2 of the stamped work 1 are circular, they are not limited to this. The shape of the recess 3, pin 4 and base 6 can be various shapes such as ellipse or polygon.

[0205] (3) In the first and second embodiments described above, although the groove 5 in the thickness direction view of the main body 2 of the stamped work 1 is circular, it is not limited to this. The shape of the groove 5 can be various shapes such as ellipse, C-shape or polygon.

[0206] (4) In the first to third embodiments described above, although the shape of the groove 5 in the cross-sectional view of the stamped work 1 parallel to the thickness direction of the main body 2 is trapezoidal, it is not limited to this. The shape of the groove 5 can be various shapes such as V-shape, U-shape, rectangle, etc.

[0207] (5) The shape of the punch 81 of the first mold 80, the shape of the hole 92 of the second mold 90, the shape of the base forming part 96, and the shape of the protrusion 93 can also be various shapes that match the shapes of the recess 3, pin 4, base part 6, and groove part 5 of the stamped workpiece 1.

[0208] (6) The pin 4 of the stamped part 1 is not limited to the purpose of riveting and fixing the stamped part 1 to other parts, but can also be a structure for other purposes.

[0209] (7) In addition to stamping the recess 3, pin 4, base 6 and groove 5 in the main body 2, the stamped part 1 can also be processed other than stamping.

[0210] This invention is not limited to the embodiments described above and can be appropriately modified. Furthermore, the various embodiments described above are not unrelated to each other, and can be appropriately combined except in cases where combination is clearly impossible. Additionally, in the various embodiments described above, the elements constituting the embodiment are not necessarily essential, except where they are specifically stated to be necessary or are clearly considered necessary in principle. Furthermore, in the various embodiments described above, when referring to the number, value, quantity, range, etc., of the constituent elements of the embodiment, the number is not limited to that specific number, except where it is specifically stated to be necessary or is clearly limited to that specific number in principle. Furthermore, in the various embodiments described above, when referring to the shape, positional relationship, etc., of the constituent elements, the shape, positional relationship, etc., is not limited to that shape, positional relationship, etc., except where it is specifically stated to be necessary or is limited to that specific shape, positional relationship in principle.

Claims

1. A press worked product, characterized by, have: plate-like main body; A recess is provided on a first surface of the main body portion facing the thickness direction; A pin is provided on the second surface of the main body, which is opposite to the first surface, at a position corresponding to the recess, and the shape of the pin in the thickness direction view of the main body is formed to be smaller than the recess and protrudes in the thickness direction of the main body; as well as The groove is recessed from the second surface of the main body toward the first surface, is formed in a C-shape in the thickness direction view of the main body, and surrounds a portion of the area around the pin.

2. The stamped product according to claim 1, characterized in that, The location of the groove is within a range that is outside the inscribed circle of the shape of the recess in the view relative to the thickness of the main body, and inside the range that is within a distance equal to the radius of the circumscribed circle of the shape of the recess plus 1.5 times the thickness of the main body.

3. The stamped product according to claim 1 or 2, characterized in that, The depth of the groove is in the range of 2% to 20% relative to the thickness of the main body.

4. The stamped product according to claim 1 or 2, characterized in that, The groove has a tapered inner wall surface whose width gradually decreases from the second surface toward the first surface in a cross-sectional view parallel to the thickness direction of the main body.

5. The stamped product according to claim 1 or 2, characterized in that, It also includes a pedestal portion disposed around the pin on the second surface side of the main body portion, and having a surface perpendicular to the axis of the pin. The shape and size of the recess in the thickness direction view of the main body are the same as or larger than the shape and size of the pedestal portion. The groove is configured to surround at least a portion of the pin and the base portion.

6. The stamped product according to claim 1 or 2, characterized in that, In a cross-sectional view parallel to the thickness direction of the main body, the distance between the recess and the groove is greater than the distance between the recess and the second surface.

7. A press working apparatus that manufactures a press working product, characterized by comprising: have: A first mold is disposed on a first surface side of the plate-shaped main body portion of the stamped work, facing the plate thickness direction. as well as The second mold is disposed on the second surface side of the main body, which is located on the opposite side to the first surface. The first mold has: A punch that forms a recess on the first surface of the body portion; and A demolding device that presses against the first surface on the outside of the punch. The second mold has: A base having a surface that contacts the second surface of the main body; A hole is provided at a position corresponding to the punch and its shape in the thickness direction view of the main body is smaller than that of the punch. The hole is formed into a pin protruding from the second surface. as well as A protrusion that protrudes from the base toward the first mold side and surrounds a portion of the hole, forming a C-shaped groove in the thickness direction view of the main body on the second surface.

8. The stamping apparatus according to claim 7, characterized in that, In the second mold, the location of the protrusion is located outside the inscribed circle of the punch shape in the view relative to the thickness of the main body portion, and inside the location of the protrusion at a distance equal to the radius of the circumscribed circle of the punch shape plus 1.5 times the thickness of the main body portion.

9. The stamping apparatus according to claim 7 or 8, characterized in that, The height of the protrusion is in the range of 2% to 20% relative to the thickness of the main body.

10. The stamping apparatus according to claim 7 or 8, characterized in that, The protrusion has a tapered outer wall surface, the width of which gradually decreases from the base toward the first mold side in a cross-sectional view parallel to the thickness direction of the main body.

11. The stamping apparatus according to claim 7 or 8, characterized in that, The second mold also has a pedestal forming portion around the hole, which forms the pedestal portion on the second surface side of the main body, and the pedestal portion has a surface perpendicular to the axis of the pin. The shape and size of the punch in the thickness direction view of the main body are the same as or larger than the shape and size of the pedestal forming part. The protrusion is configured to surround at least a portion of the hole and the pedestal forming portion.

12. The stamping apparatus according to claim 7 or 8, characterized in that, When the punch is closest to the base during stamping, the distance between the punch and the protrusion is greater than the distance between the punch and the base.

13. A stamping process for manufacturing stamped products, characterized in that, It includes the following processes: Prepare a stamping apparatus, which includes a first die and a second die. The first die has a punch and a ejector. The punch forms a recess on a first surface of the main body of the stamped workpiece facing the thickness direction. The ejector presses the first surface on the outside of the punch. The second die has a base, a hole, and a protrusion. The base has a surface that contacts a second surface of the main body located on the opposite side of the first surface. The hole is located at a position corresponding to the punch and is shaped to be smaller than the punch in the thickness direction view of the main body. The hole forms a pin protruding from the second surface. The protrusion protrudes from the base toward the first die side and surrounds a portion of the hole. The protrusion forms a C-shaped groove in the thickness direction view of the main body on the second surface. The main body portion of the stamped workpiece, which is the part to be processed, is disposed between the first mold and the second mold; The demolding device is moved toward the second mold side, and at least a portion of the groove is formed on the second surface by the protrusion; The demolding device is further moved toward the second mold side to form the groove on the second surface through the protrusion, and the punch is moved toward the second mold side to form the recess on the first surface and to form the pin through the hole; and Move the first mold away from the second mold, and remove the stamped product from between the first mold and the second mold.

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