Model handrail and method for making model handrail

Abstract

To provide a plate-like handrail satisfying a viewpoint of reality in a railway model vehicle, especially in an N gauge (1 / 150 scale), and a method for making the plate-like handrail.MEANS FOR SOLVING THE PROBLEM: A model handrail 104 has a plate-shaped handrail main body 104a and a connection portion 104b. The handrail main body 104a and the connection portion 104b are integrally formed from metal. The connection portion 104b extends from a back surface 104ad of the handrail main body 104a. The handrail main body 104a is formed so that its width when viewed from the front is larger than its width when viewed in a plan view, and a front surface viewed from the front is formed flat. The back surface 104ad of the handrail main body 104a and a side surface of the connection portion 104b are formed convexly. A space exists between the back surface 104ad and the model body when the model handrail 104 is connected to the model body.SELECTED DRAWING: Figure 11

Description

Technical Field

[0001] The present invention relates to a handrail for a model and a method for manufacturing the handrail for a model.

Background Art

[0002] As a way of enjoying railway model vehicles, especially N gauge (1 / 150 scale), the style of users purchasing and collecting finished products is the mainstream. On the other hand, in order to realize a mode closer to real railway vehicles (hereinafter also referred to as "real vehicles"), some highly specialized users enjoy modification and handicraft work, such as purchasing an assembly kit and assembling it, modifying a purchased finished product, or creating parts by themselves using resin or metal materials.

[0003] There are also many manufacturers (so-called "third parties") that provide kits, parts, and materials to meet the needs of such highly specialized users. Enjoying such modification and handicraft work has long been a part of the formation of the railway model culture.

[0004] By the way, in real railway vehicles, conventionally, a number of handrails, footrests, and other hooks (hereinafter collectively referred to as "handrails") for workers are attached to the outside of the vehicle body, especially the front, connection part, roof, etc. For example, handrails 302 to 320 are attached to the front of the real vehicle 300 in FIG. 1.

[0005] Conventionally, handrails are often manufactured by bending a round bar-shaped metal material into a required shape, such as handrails 302 to 320, and are often welded to the vehicle body. On the other hand, in recent years, from the perspective of emphasizing design, there have been an increasing number of cases where plate-shaped handrails are adopted on the front surface of actual vehicles. The plate-shaped handrails have a structure in which a connecting member is connected to the back surface of the plate-shaped handrail main body, and the main body of the handrail is fixed to the front surface of the vehicle through the connecting member (hereinafter referred to as the "plate-shaped handrail structure"). For example, on the front surface of the actual vehicle 300A in FIG. 2, in the plate-shaped handrail structure, plate-shaped handrails 302A, 304A, and 306A are attached. The plate-shaped main body of the plate-shaped handrail 302A etc. is not directly connected to the front surface of the vehicle, but is connected through a connecting member fixed to the back surface of the main body. Therefore, a state exists in which there is a space between the plate-shaped main body and the front surface of the vehicle (hereinafter also referred to as the "floating state").

[0006] In order to realize a model representation of round bar-shaped handrails, a user has adopted a manufacturing method in which, for example, holes are drilled in a resin or metal model vehicle, and a handrail created by bending a metal wire with a diameter of about 0.2 to 0.3 millimeters is inserted into the hole from the surface side of the model vehicle and fixed with an adhesive or solder on the back surface side. Also, third-party parts of handrails with the required shape reproduced by etching are commercially available, and users also purchase the commercially available parts and attach them for model vehicles.

[0007] The present invention realizes a plate-shaped handrail as described above in a model. As a premise, with reference to FIGS. 3 and 4, how the handrails of an actual vehicle are visually recognized will be described.

[0008] FIG. 3 and FIG. 4 are diagrams for explaining the plate-shaped handrail 302A and the like of the actual vehicle 300A in FIG. 2. FIG. 4(a) shows the plate-shaped handrails 302A, 304A, and 306A connected to the front portion 300Aa. FIG. 4(b) shows the round bar-shaped handrail 308A connected to the front portion 300Aa. FIG. 4(c) shows the plate-shaped tread plate 312A connected to the front portion 300Aa. In FIGS. 3 and 4, light hits the front portion 300Aa from above and in front as indicated by the arrow X1.

[0009] As shown in FIGS. 3 and 4(a), a shadow 320A is generated by the plate-shaped handrails 302A, 304A, and 306A. As shown in FIG. 4(a), the shadow 320A is composed of a shadow 320Aa and a shadow 320Ab. The shadow 320Aa is the shadow of the main body portions 302Aa, 304Aa, and 306Aa of the plate-shaped handrails 302A, 304A, and 306A. The shadow 320Ab is the shadow of the connecting members 302Ab, 304Ab, and 306Ab. The shadow 320Aa is not continuous with the main body portion 302Aa, etc., but the shadow 320Ab is continuous with the connecting member 302Ab, etc. This is because the main body portion 302Aa, etc. floats from the front portion 300Aa, but the connecting member 302Ab, etc. is not in a floating state from the front portion 300Aa. Therefore, even from the state of the shadow, it can be recognized whether the object that is the source of the shadow is in a floating state from the front portion 300Aa.

[0010] As shown in FIGS. 3 and 4(b), a shadow 322A is generated by the round bar-shaped handrail 308A. The shadow 322A is composed of a shadow 322Aa and a shadow 322Ab. The shadow 322Aa is the shadow of the main body portion 308Aa which is a portion of the handrail 308A parallel to the front portion 300Aa. The shadow 322Ab is the shadow of the connecting portion 308Ab which is perpendicular to the front portion 300Aa and connected to the front portion 300Aa. The shadow 322Aa is not continuous with the main body portion 308Aa, but the shadow 322Ab is continuous with the connecting portion 308Ab. This is because the main body portion 308Aa is in a floating state from the front portion 300Aa, but the connecting portion 308Ab is not in a floating state from the front portion 300Aa.

[0011] As shown in FIGS. 3 and 4(c), a shadow 326A is generated by the tread plate 312A. The shadow 326A is continuous with the tread plate 312A. This is because the tread plate 312A is not in a floating state from the front surface portion 300Aa.

[0012] As described above, whether each part such as the plate-shaped handrail 302A is in a floating state from the front surface portion 300Aa can be recognized not only directly from each part such as the plate-shaped handrail 302A, but also from the state of the shadow.

[0013] Next, referring to FIG. 5, the shadows generated on the handrails of the actual vehicle itself will be described. FIG. 5(a) shows the plate-shaped handrail 304A, and FIG. 5(b) shows the main body portion 308Aa of the round bar-shaped handrail 308A.

[0014] As shown in FIG. 5(a), when light hits the plate-shaped handrail 304A from the direction of arrow X1, it evenly hits the main body portion 304Aa, and no shadow is generated in the main body portion 304Aa. This is because the surface of the main body portion 304Aa is flat.

[0015] On the other hand, as shown in FIG. 5(b), when light hits the round bar-shaped handrail 308A from the direction of arrow X1, the upper side portion 308Aaa is hit by the light, but the lower side portion 308Aab is not hit, and it is relatively dark and visually recognized as a shadow 308Abs. This is because the surface of the main body portion 308Aa is not flat but a curved surface.

[0016] From the above, whether each part such as the plate-shaped handrail 302A is flat can also be recognized by the relative light and dark in the part of the handrails themselves, that is, the state of the shadow.

[0017] Next, the model representation of the plate-shaped handrail will be described. In the model representation, the perspective of looking like the real thing (hereinafter referred to as the "reality perspective") is highly emphasized. For this purpose, it is important that the main body of the plate-shaped handrail is recognized as being plate-shaped. Also, it is important that it is visually recognized that the main body of the plate-shaped handrail is connected to the front part of the model vehicle via a connecting member, that is, it is visually recognized as being in a floating state. The expression of the floating state can also be said to be the three-dimensionalization of handrails.

[0018] The conditions for satisfying the reality perspective (hereinafter also referred to as the "conditions for three-dimensionalization of handrails") are, first, that the front of the main body of the plate-shaped handrail is flat, second, that the width (height) of the front of the main body is larger than the width of the upper surface of the main body, and third, that there is a space between the main body and the front part of the model vehicle in order to be visually recognized as being in a floating state.

[0019] And in a railway model vehicle, especially in the N gauge (1 / 150 scale), it is necessary to satisfy the above-mentioned conditions for three-dimensionalization of handrails in a very small size. Since the track width of the N gauge is 9 millimeters (mm), the dimensions of the model vehicle are also appropriate. The size of the front part of the model vehicle in a front view is approximately 15 millimeters in both length and width. For the plate-shaped handrail for models, in order to realize the above first perspective, second perspective, and third perspective, for example, as shown in FIG. 6, the width (height) h1 of the front 420aa of the main body 420a of the handrail 420 is about 0.2 to 0.6 millimeters (mm), the width w1 of the upper surface, lower surface, and side surface, and the width w2 of the connecting part 420b are ideally about 0.15 millimeters to 0.4 millimeters.

[0020] In the case of a round bar-shaped handrail, a fabrication method was adopted in which the user drilled a hole in a resin or metal model vehicle, for example, and inserted a handrail created by bending a metal wire with a diameter of about 0.2 to 0.3 millimeters into the hole from the surface and fixed it with an adhesive or solder on the back side. Also, parts of handrails with the required shape reproduced by etching are commercially available, and users have also purchased the commercially available parts and installed them for model cars.

[0021] However, in the case of a plate-shaped handrail, the situation is different from that of a round bar-shaped handrail. Hereinafter, on the premise of explaining a metal plate-shaped handrail, the case of manufacturing a model vehicle and a plate-shaped handrail integrally by resin molding will be described, and then the metal plate-shaped handrail will be described. Actually, there is an example in which the model vehicle and the handrail are integrally molded, and it is obvious at a glance that there is no gap between the front part and the handrail (see, for example, Fig. 12(b) of Patent Document 1). Similarly, Fig. 7 is a view showing the front part of a resin model vehicle 200, and the model vehicle 200 and the handrail 202 are integrally molded. It is clearly visible that there is no gap between the front part 200a and the main body part of the handrail 202.

[0022] Fig. 8 is a view for explaining the shadow when plate-shaped handrails 204, 206, and 208 made of resin are formed in the model vehicle 200A. When light hits from above and in front, a shadow 220 continuous with the plate-shaped handrails 204, 206, and 208 is formed in the front part 200Aa. Therefore, it is difficult to realize an ideal representation of the plate-shaped handrail that satisfies the above first to third conditions by integrally molding the resin model vehicle 200A and the plate-shaped handrail 204, etc.

[0023] Of course, it is theoretically possible to resin-mold a plate-shaped handrail as a separate member from the model vehicle body and then connect it to the model vehicle body. However, as described above, since the ideal plate-shaped handrail for models is very small and thin, resin molding itself is actually difficult. Also, even if resin molding is possible, there are strength problems, so it is not practical.

[0024] Therefore, in order to satisfy the above first to third conditions, instead of integrally resin-molding the plate-shaped handrail with the model vehicle, it is necessary to create it as a separate metal member and connect it to the model vehicle. The metal is, for example, brass (an alloy composed of copper, zinc, and nickel), copper, bronze, or stainless steel. As shown in FIG. 6, since the plate-shaped handrail 420 is composed of a handrail main body 420a and a connecting portion 420b, it cannot be simply created by bending a plate-shaped material. Therefore, it is necessary to manufacture it from a metal plate.

[0025] The plate-shaped handrail 420 can theoretically also be manufactured by machining such as cutting or punching with a press using a metal plate as the material. However, as described above, since the parts are very small and thin, the metal plate may deform and deviate from the desired shape or be damaged during machining. Also, the strength of the product may deteriorate due to the forces acting during machining. As described above with reference to FIG. 6, the width (height) h1 of the front surface 420aa of the main body portion 420a of the handrail 420 is about 0.2 to 0.6 millimeters (mm), the widths w1 of the upper surface, lower surface, and side surfaces, and the width w2 of the connecting portion 420b are ideally about 0.15 to 0.4 millimeters. It is difficult to manufacture small and thin objects by machining.

[0026] Also, the plate-shaped handrail 420 can theoretically also be manufactured by casting such as lost-wax processing. For relatively large products, for example, in the HO gauge (1 / 80 scale), cast products are actually sold. However, cast products have warping and deformation peculiar to the manufacturing method of casting, and it is difficult to avoid this, and there is at least a problem with the stability of the quality as a product. If metal parts of the N gauge are manufactured by casting, it is obvious that the defect rate will be higher than in the case of the HO gauge because the dimensions of the parts are small. In order to reduce the defect rate, it is necessary to make the parts larger than the original reduction rate of the N gauge, but then there is an essential problem that the realism perspective is impaired.

[0027] Also, the plate-shaped handrail 420 can theoretically be manufactured by wire electrical discharge machining. However, in order to form a complex shape by wire electrical discharge machining, it requires a relatively long time for the machining operation. In addition, in the case of a fine part such as the plate-shaped handrail 420, it is difficult to hold the member during machining, so at least mass production is difficult.

[0028] Therefore, it is realistic to manufacture a product similar to the plate-shaped handrail 420 by etching a metal plate. In order to manufacture fine parts for model vehicles, from the perspective of cost, it is common to perform double-sided etching in wet etching. That is, the parts are cut out from the metal plate by double-sided etching.

[0029] FIG. 9 is a diagram for explaining an actually sold product. The handrail 440 is sold in a state where the main body portion 440a and the connecting member 440b are manufactured separately, and the user inserts and fixes the protruding portion 440ba of the connecting member 440b into the through hole 440ab of the main body portion 440a. From the structure in which the through hole 440ab is formed in the main body portion 440a by etching, the front surface 440aa and the back surface 440ad of the main body portion 440a coincide with the front surface (upper surface) and the back surface (bottom surface) of the metal plate. Also, in the case of this structure, in order to ensure mechanical strength, it is necessary to ensure an appropriate width above and below the through hole 440ab. For this reason, since it is necessary to make the widths of the front surface 440aa and the back surface 440ad larger than the width of the metal plate, it is necessary to coincide with the front surface and the back surface of the metal plate.

[0030] When the etching of the metal plate is completed, the front and back surfaces of the metal plate become flat because the original front and back states are maintained. Therefore, making the front and back surfaces of the product coincide with the front and back surfaces of the metal plate is also suitable for flattening the front surface 440aa and the back surface 440ad of the main body portion 440a. The widths w1 of the upper surface, the lower surface, and the side surfaces of the main body portion 440a are the thickness of the metal plate. The height h4 of the connecting member 440b is also the thickness of the plate material. Here, from the viewpoint of ensuring the strength when the connecting member 440b is inserted and fixed into the through-hole 440ab, the height h2 needs to be higher than the height h1 (see FIG. 6) which is the height based on the original scale of the N gauge. For example, when the thickness of the metal plate is 0.25 millimeters, the height h4 of the connecting member 440b is 0.25 millimeters, and the height h3 of the through-hole 440ab needs to be the same or slightly larger. From the viewpoint of strength, it is necessary to ensure about 0.2 millimeters for the upper and lower portions of the through-hole 440ab respectively, so the height h2 of the main surface 440aa of the handrail 440 needs to be at least 0.65 millimeters (mm). Therefore, the handrail 440 deviates from the height based on the original scale of the N gauge, and the sense of reality is impaired.

[0031] Then, by etching the metal plate, it is conceivable to integrally form the main body portion and the connecting member. However, due to the phenomenon (undercut) where corrosion also progresses under the etching mask, there is a problem that highly precise microfabrication is difficult.

Prior Art Documents

Patent Documents

[0032]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0033] As described above, in a railway model vehicle, particularly in an N gauge (1 / 150 scale) model which has a relatively large reduction ratio, it has been difficult to realize a plate-shaped handrail that satisfies the perspective of reality.

[0034] The present invention attempts to solve such problems, and an object thereof is to provide a plate-shaped handrail that satisfies the perspective of reality and a method for manufacturing the plate-shaped handrail in a railway model vehicle, particularly in an N gauge (1 / 150 scale).

Means for Solving the Problem

[0035] The first invention is a handrail for a model, the handrail for the model having a plate-shaped handrail body and a connecting portion for connecting the handrail body and the model body, the handrail body and the connecting portion being integrally formed of metal, the connecting portion extending from the back surface of the handrail body, the handrail body being formed such that the width in a front view is larger than the width in a plan view, and the front surface visible in the front view being formed flat, the back surface of the handrail body and the side surface of the connecting portion being formed convexly, and at the boundary portion where the handrail body and the connecting portion are integrated, the convex shape of the back surface of the handrail body and the convex shape of the side surface of the connecting portion are integrally formed, and the handrail for the model is configured such that a space exists between the back surface and the model body when the handrail for the model is connected to the model body.

[0036] According to the configuration of the first invention, since the front surface of the handrail main body is formed flat, it is visually recognized as flat. Also, since the width of the handrail main body in the front view is formed larger than the width in the plan view, it is visually recognized as plate-shaped. Furthermore, since there is a space between the back surface of the handrail main body and the model main body, the handrail main body appears to float from the model main body. Thus, in a railway model vehicle, particularly in the N gauge (1 / 150 scale), a plate-shaped handrail that satisfies the perspective of reality can be provided. Furthermore, the back surface of the handrail main body and the side surface of the connecting portion are formed in a convex shape, and moreover, since the convex shape of the back surface of the handrail main body and the convex shape of the side surface of the connecting portion are integrally formed at their boundary portion, mechanical strength is ensured.

[0037] The second invention is a method for manufacturing a model handrail having a plate-shaped handrail main body and a connecting portion for connecting the handrail main body and the model main body, which includes an etching step of forming an intermediate shape of the model handrail from a metal plate by etching, and a wire cutting step of removing a part of the intermediate shape by wire cutting to form a final shape of the model handrail. In the etching step, the intermediate shape is formed integrally in a manner in which the connecting portion extends from the back surface of the handrail main body. In the etching step, the upper surface and the bottom surface of the intermediate shape coincide with the upper surface and the bottom surface of the metal plate, and the surfaces other than the upper surface and the bottom surface of the intermediate shape coincide with the portions where etching progresses on the metal plate. In the etching step, the surfaces other than the upper surface and the bottom surface of the intermediate shape are formed in a convex shape. The width of the handrail main body in the plan view of the intermediate shape is formed larger than the width (height) of the handrail main body in the front view. In the wire cutting step, the portion formed in a convex shape on the front surface of the handrail main body is removed, and in the final shape, the width (height) of the handrail main body in the front view is formed larger than the width of the handrail main body in the plan view. This is a method for manufacturing a model handrail.

[0038] According to the configuration of the second invention, an intermediate shape is formed by etching. Since the upper and lower surfaces of the intermediate shape coincide with the upper and lower surfaces of the metal plate, they are flat. On the other hand, the surfaces of the intermediate shape other than the upper and lower surfaces coincide with the portions where etching progresses on the metal plate. Therefore, the surfaces of the intermediate shape other than the upper and lower surfaces are formed in a convex shape in a direction perpendicular to the direction connecting the upper and lower surfaces, rather than in a flat state, due to the undercut caused by etching. Here, in order to avoid a large deviation of the final shape from the scale of N gauge, it is important to integrally form the handrail body and the connecting portion by etching. From the perspective of reality, it is important that the front of the handrail body is flat, but in the etching process, the perspective that the front of the handrail body is flat is not realized. The perspective that the front of the handrail body is flat is achieved in the wire cutting process. That is, in the wire cutting process, the convex portion formed on the front of the handrail body is removed, so that the front of the final shape becomes flat. And the wire electrical discharge machining in the wire cutting process is a non-contact machining method using discharge, and the physical force applied to the metal plate as the material is minimized, so that the width of the handrail body in plan view can be processed to a dimension smaller than the width (height) in front view, that is, the thickness of the metal plate, without imposing an excessive burden on the metal plate. Furthermore, in the etching process, an intermediate shape integrated in a manner in which the connecting portion extends from the back surface of the handrail body is formed, and this manner is maintained even in the final shape. Therefore, when the model handrail is connected to the model body, the handrail body is connected to the model body via the connecting portion, and the body of the model handrail appears to float from the model body.

[0039] A third invention is a method for manufacturing a model handrail, which is configured in the second invention, and in the wire cutting process, the handrail body of the intermediate shape is cut on a surface biased toward the front side of the intermediate shape and parallel to the front in the final shape.

[0040] According to the configuration of the third invention, while removing the convex portion on the front surface of the handrail main body in the intermediate shape, the mechanical strength corresponding to the thickness (width) of the handrail main body can be ensured accordingly.

[0041] The fourth invention is a method for manufacturing a model handrail, in the configuration of the second invention or the third invention, wherein the difference in the width in plan view of the handrail main body in the intermediate shape and the width in plan view of the handrail main body in the final shape is equal to or greater than the width in plan view of the convex portion generated on the front surface of the handrail main body in the intermediate shape.

[0042] According to the configuration of the fourth invention, in the wire cutting process, a handrail main body having a flat front surface can be formed while avoiding technical difficulties.

[0043] The fifth invention is a method for manufacturing a model handrail, in the configuration of the second invention, wherein in the etching process, an intermediate product including a plurality of the intermediate shapes is formed, and in the wire cutting process, a final product including a plurality of the final shapes is formed.

[0044] According to the configuration of the fifth invention, it is efficient because a plurality of intermediate shapes and final shapes are manufactured together.

Advantages of the Invention

[0045] According to the present invention, in a railway model vehicle, particularly in the N gauge (1 / 150 scale), it is possible to provide a plate-shaped handrail that satisfies the perspective of reality, and a method for manufacturing the plate-shaped handrail.

Brief Description of the Drawings

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Mode for Carrying Out the Invention

[0047] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail. In the following description, the same reference numerals are given to the same configurations, and the description thereof will be omitted or simplified. Note that the description of configurations that can be appropriately implemented by those skilled in the art will be omitted, and only the basic configuration of the present invention will be described.

[0048] <Configuration of the plate-shaped handrail> FIG. 10 is a view showing a model vehicle 100 of a train. The model vehicle 100 is an example of a model body. Plate-shaped handrails 102, 104, and 106 are connected to the front portion 100a of the model vehicle 100. The handrails 102, 104, and 106 are an example of model handrails and also an example of plate-shaped handrails. Light is hitting the front portion 100a in the direction indicated by the arrow X1, that is, from above and in front, and a shadow 120 is generated.

[0049] FIG. 11 is a schematic enlarged view showing the handrail 104. FIG. 11(a) shows the state before paint is applied to the handrail 104. The handrail 104 is sold in a state before paint is applied, and a desired paint is applied by the user.

[0050] The handrail 104 has a plate-shaped handrail main body portion 104a and a connecting portion 104b for connecting the handrail main body portion 104a and the model vehicle 100. The handrail main body portion 104a and the connecting portion 104b are integrally formed of metal. The handrail main body portion 104a is an example of a handrail main body.

[0051] The connecting portion 104b extends from the back surface 104ad of the handrail main body portion 104a in a direction perpendicular to the longitudinal direction of the handrail main body portion 104a. Therefore, when the handrail 104 is connected to the model vehicle 100, a space 100s (see FIG. 10) exists between the back surface 104ad and the front surface 100a of the model vehicle 100.

[0052] The handrail main body 104a is formed such that the width (height) H1 in the front view as viewed from the direction indicated by the arrow X2 is larger than the width W2 in the plan view as viewed from the direction indicated by the arrow Z1, and the front surface 104aa visible in the front view is formed flat. The width (height) H1 in the front view is 0.2 millimeters (mm) to 0.6 millimeters (mm), preferably 0.2 millimeters (mm) to 0.3 millimeters (mm). The width W2 in the plan view is 0.15 millimeters (mm) to 0.6 millimeters (mm), preferably in the range of 0.15 millimeters (mm) to 0.3 millimeters (mm), but is smaller than the width (height) H1 in the front view as described above. Therefore, although the handrail main body 104a is a fine part, it is visually recognized as a plate-like object. In the present embodiment, the width (height H1) is 0.25 millimeters (mm), and the width W2 is defined as less than 0.25 millimeters (mm). For example, the width W2 is defined in the range of 0.15 or more and less than 0.20 millimeters (mm).

[0053] In the handrail 104, the upper surface 104ab, the lower surface 104ac of the handrail main body 104a, the upper surface 104ba, and the lower surface 104bc of the connecting portion 104b are formed flat. On the other hand, the back surface 104ad of the handrail main body 104a has a convex portion 104as and is formed in a convex shape. Further, the side surface 104bb visible in the side view as viewed from the arrow X3 direction of the connecting portion 104b is formed in a convex shape. The mechanical strength of the handrail 104 is strengthened by the side surface 104bb of the connecting portion 104b and the back surface 104ad of the handrail main body 104a being formed in a convex shape. Furthermore, as shown in Fig. 11(b), at the boundary portion 104s where the side surface 104bb of the connecting portion 104b and the back surface 104ad of the handrail main body 104a are integrated, the convex shapes of both are integrated, and the mechanical strength of the handrail 104 is further strengthened.

[0054] FIG. 12 is a view showing a state in which paint Pa is applied to the handrail main body portion 104a of the handrail 104. Since the front surface 104aa and the upper surface 104ab of the handrail main body portion 104a are flat, they are flat even when the paint Pa is applied. Therefore, the light from the direction of arrow X1 hits the front surface 104aa evenly. For this reason, there is no portion that becomes relatively dark, that is, a shaded portion, on the front surface 104aa.

[0055] On the other hand, the back surface 104ad is formed in a convex shape. Since this convex shape is a fine convex shape, the back surface 104ad is visually recognized as a curved surface by the human eye. When the paint Pa is applied, the convex shape is relaxed and is more clearly visually recognized as a curved surface. However, when the handrail 104 is connected to the vehicle model 100, the back surface 104ad is in a position where it is difficult to be visually recognized from the outside, so it does not impair the realism.

[0056] Note that since the side surface of the connecting portion 104b is also convex, it is visually recognized as a curved surface by the human eye. When the paint Pa is applied, the convex shape is relaxed and is more clearly visually recognized as a curved surface.

[0057] From the above, the handrail main body portion 104a of the handrail body 104 is visually recognized as a plate-like object and is visually recognized in a state floating from the front surface 100a of the model vehicle 100. Note that, from the viewpoint of faithfully scaling the plate-like handrail mounted on the actual vehicle, unlike this embodiment, it is desirable that the back surface 104ad of the handrail main body portion 104a is also flat. However, in a vehicle model of a fine model such as N gauge, since the back surface 104ad of the handrail 104a is in a position where it is difficult to be visually recognized from the outside, it is sufficient that the front surface of the handrail main body portion 104a is flat and is visually recognized as a plate shape.

[0058] <Conceptual Explanation of Manufacturing Method of Plate-like Handrail> First, with reference to FIG. 13, the manufacturing method of the handrail 104 will be conceptually described. FIG. 13 shows only a part of the front surface of the main body portion 104a of the handrail 104.

[0059] As shown in Fig. 13(a), first, in the etching process, a metal plate is etched to form an intermediate shape 104X1 of the handrail body. The intermediate shape 104X1 has a width (height) H1 in a front view as viewed from the direction indicated by arrow X2, and has a width W1 as the width in a plan view as viewed from the direction indicated by arrow Z1. The width (height) H1 is smaller than the width W1. The width (height) H1 is, for example, 0.25 millimeters (mm). The width W1 is, for example, in the range of 0.26 to 0.30 millimeters (mm).

[0060] The etching process is carried out by wet etching from both sides in a state where a mask (required pattern of photoresist) is formed on the upper surface and the lower surface of the metal plate, that is, the surfaces corresponding to the upper surface 104X1b and the lower surface 104X1e of the intermediate shape 104X1. Therefore, although the erosion by wet etching basically proceeds in the directions indicated by arrows Z1 and Z2, since the progress direction of the erosion is isotropic, the erosion proceeds not only in the directions of arrows Z1 and Z2 but also in the directions perpendicular to the directions of arrows Z1 and Z2. As a result, the front surface 104X1a and the back surface 104X1d are not flat and are formed convex outward as shown in Fig. 13(a).

[0061] Next, in the wire cutting process, the final shape 104X2 of the handrail body is formed. In this specification, the term "wire cutting" is used synonymously with wire electrical discharge machining. Wire cutting is a machining method that uses a wire-shaped elongated electrode (for example, a wire with a diameter of about 0.2 mm). Discharge is caused with a linearly stretched wire electrode close to the workpiece, melting the workpiece to machine it. Move the intermediate shape 104X1 toward Wire1, which is the energized wire, cut the intermediate shape 104X1 along line L1 at the A-A line, and form the final shape 104X2 shown in Fig. 13(b). The cutting plane is a plane parallel to the front surface 104X2a of the final shape 104X2 and is offset toward the front surface 104X1a rather than the back surface 104X1d of the intermediate shape 104X1. And line L1 deviates from the most protruding part 104X1ap of the front surface 104X1a by at least the width Wx1 of the convex portion or more. The width Wx1 is, for example, 0.10 millimeter (mm) to 0.20 millimeter (mm). In the present embodiment, line L1 deviates from the most protruding part 104X1ap of the front surface 104X1a at a distance greater than the width Wx1 of the convex portion.

[0062] The convex portion of the front surface 104X1a of the intermediate shape 104X1 formed in the etching process is cut and removed in the wire cutting process. That is, in the wire cutting process, the portion including the convex portion with the width Wx1 shown in Fig. 13(a) is cut. As a result, the width W1 of the upper surface 104X1b of the intermediate shape 104X1 becomes smaller and becomes the width W2 of the upper surface 104X2b of the final shape 104X2. And the front surface 104X2a of the final shape 104X2 is formed in a flat state. On the other hand, the shapes other than the upper surface 104X1b, the bottom surface, and the front surface 104X1a are maintained the same as those of the intermediate shape 104X1.

[0063] The width (height) H1 in the front view of the final shape 104X2 is the same as that of the intermediate shape 104X1. In contrast, the width W2 in the plan view of the final shape 104X2 is smaller than the width W1 of the intermediate shape 104X1. And the width (height) H1 is larger than the width W2. The width W2 is, for example, in the range of 0.15 to 0.24 millimeters (mm).

[0064] As described above, while the front surface 104X2a of the final shape 104X2 is flat, the front surface 104X1a of the intermediate shape 104X1 is formed convex outward. The reason why the front surface 104X1a is formed convex is due to the undercut caused by wet etching. In the wire cutting process, as a result of cutting the portion including the convex portion with the width Wx1 shown in Fig. 13(a), the final shape 104X2 becomes the width W2. The width W2 is smaller than the width W1. The width W2 is smaller than the width W1 by an amount greater than or equal to the undercut width Wx1. And the width W1 is larger than the height H1, but the width W2 is smaller than the height H1.

[0065] The mask (required pattern of photoresist) formed in the etching process is designed so that there is no manufacturing technical problem in manufacturing the final shape 104X2 in the subsequent wire cutting process. That is, the mask is formed in the shape in the plan view of the intermediate shape 104X1, not the shape in the plan view of the final shape 104X2. And the shape in the plan view of the intermediate shape 104X1 is formed larger than the shape in the plan view of the final shape 104X2 in consideration of the fact that the convex formation due to undercut and the cutting of the portion including the convex in the wire cutting process can be carried out without manufacturing technical problems.

[0066] As shown in Fig. 13(c), paint Pa is applied to the final shape 104X2 to obtain the post-application shape 104X3. The front surface 104X3a and the upper surface 104X3b of the post-application shape 104X3 are flat. In contrast, the paint is applied to the convex shape of the back surface 104X2d of the final shape 104X2 on the back surface 104X3d, and the convexity is relaxed to form a curved surface. Even after the paint is applied, the width (height) H2 is larger than the width W3.

[0067] <Specific description of the manufacturing method> Next, with reference to FIG. 14 and the like, the manufacturing method of the handrail 104 will be specifically described. The handrail 104 is manufactured by an etching process and a wire cutting process.

[0068] In the etching process, an intermediate shape 104X1 of the handrail 104 (see FIGS. 15(b) and 16) is formed by wet etching on both sides.

[0069] In the wire cutting process, a part of the intermediate shape 104X1 is removed by wire electrical discharge machining to form the final shape 104X2 of the handrail 104 (see FIG. 20).

[0070] That is, in the intermediate shape 104X1, an extra part to be removed by wire electrical discharge machining is formed with respect to the final shape 104X2.

[0071] A plurality of handrails 104 are manufactured and sold in a state where the final shape 104X2 is included in the final product piece (for example, the final product piece 602BE in FIG. 20). The handrail in a state connected to the final product piece is called the final shape 104X2. Then, for the user, the individual final shapes 104X2 are cut from the final product piece to become the handrails 104, and are appropriately painted and connected to the vehicle model.

[0072] First, the etching process will be described. The etching is wet etching and is double-sided etching. By double-sided etching, the metal plate 600 is corroded and dissolved with an etching solution from both sides of the metal plate 600 to perform through-hole machining on the metal plate 600. The thickness of the metal plate 600 is, for example, 0.2 millimeters (mm) to 0.3 millimeters (mm). In the present embodiment, the metal plate 600 has a thickness of 0.25 millimeters (mm) and is a silver-white plate.

[0073] As preparation for etching, a master plate (not shown) corresponding to the shape of the intermediate product 602 (Fig. 15(a)) is prepared. Subsequently, as shown in Fig. 14(a), a photoresist film RS is formed on both surfaces of the metal plate 600. Subsequently, the photoresist RS is exposed through the master plate, the photosensitive portion is made insoluble in the developer, and the unexposed portion is removed by the developer to obtain a required pattern of the photoresist RS.

[0074] Then, as shown in Fig. 14(b), the metal plate 600 other than the portion corresponding to the intermediate product 602 is exposed. Subsequently, the exposed portion of the metal plate that is not covered by the photoresist RS is dissolved and removed by the etching solution, and a desired intermediate product 602 is obtained as shown in Fig. 15(a). The intermediate product 602 includes at least one intermediate product piece 602A or the like. In the present embodiment, the intermediate product 602 includes two intermediate product pieces 602A and 602B. The intermediate product pieces 602A and 602B each include a plurality of intermediate shapes 104X1 of the plate-shaped handrail. Positioning holes 602P are formed in the intermediate product pieces 602A and 602B. In Fig. 15, one positioning hole 602P is shown for each of the intermediate product pieces 602A and 602B, but actually a plurality of positioning holes 602P are formed in each of the intermediate product pieces 602A and 602B. The positioning holes 602P are used for positioning in the wire cutting process, as will be described later.

[0075] In the etching process, the upper surface and the lower surface of the intermediate shape 104X1 coincide with the upper surface and the lower surface of the metal plate 600, and the surfaces other than the upper surface and the lower surface of the intermediate shape 104X1 coincide with the portions of the metal plate 600 where etching erosion progresses. For this reason, the upper surface and the lower surface of the intermediate shape 104X1 are flat, but the other surfaces are formed in a convex shape in a mode where the substantially center in the thickness direction protrudes as a result of undercuts occurring from both the front and back surfaces.

[0076] FIG. 15(b) and FIG. 16 are diagrams showing the intermediate product piece 602B. FIG. 17(a) is a schematic perspective view of the intermediate shape 104X1 included in the intermediate product piece 602B of FIG. 16 viewed from the direction of arrow Y1, and FIG. 17(b) is a schematic perspective view of the intermediate shape 104X1 included in the intermediate product piece 602B of FIG. 17 viewed from the direction of arrow Y2.

[0077] In the etching process, as shown in FIG. 17, an intermediate shape 104X1 is formed integrally in such a manner that the connecting portion 104X1b extends from the back surface 104X1ad of the handrail main body portion 104X1a.

[0078] In the intermediate shape 104X1 shown in FIG. 17, the height H1 of the front surface 104X1aa of the handrail main body portion 104X1a is the thickness of the metal plate 600. As shown in FIGS. 17(a) and (b), the front surface 104X1aa is not flat but is formed convex outward. This is, as described above, the result of the dissolution of the metal plate 600 progressing from both the front and back surfaces by double-sided etching, and undercuts occurring from both the front and back surfaces.

[0079] The width W1 (see FIG. 18(b)) of the handrail main body portion 104X1a in the plan view of the intermediate shape 104X1 is formed larger than the width (height) in the front view of the handrail main body 104X1a, that is, the height H1 of the front surface 104X1aa (see FIG. 18(c)).

[0080] Next, a separation process is performed. In the separation process, the intermediate product 602 including a plurality of intermediate product pieces 602A, etc. is cut to separate into individual intermediate product pieces 602A, etc. For example, the intermediate product 602 in FIG. 15(a) is cut along the line 602S to separate the intermediate product pieces 602A and 602B.

[0081] Next, the wire cutting process will be described. Hereinafter, the intermediate product piece 602B will be described, but the same processing is performed on the intermediate product piece 602A.

[0082] When the separation of the intermediate product pieces 602A and 602B is completed, the intermediate product piece 602B is cut by wire electrical discharge machining along the line L1 shown in FIGS. 18(a) to (c). As a result, the convex portion formed on the front surface 104X1aa of the handrail main body 104X1a part is removed. The width in the plan view of the intermediate shape 104X1 at the time when the etching is completed is the width W1 (see FIG. 18(b)), but the width W1 becomes smaller due to the cutting by wire electrical discharge machining.

[0083] As shown in FIGS. 18(a), (b) and (c), the line L1 is offset toward the front surface 104X1aa side rather than the back surface 104X1ad in the plan view. Then, the intermediate shape 104X1 included in the intermediate product piece 602B is cut along the line L1 in a plane parallel to the front surface 104X2aa (see FIG. 20(c)) in the final shape 104X2. And the line L1 deviates from the most protruding portion 104X1ap of the front surface 104X1a by at least the width Wx1 of the convex portion (see FIG. 13(a)). However, if the separation distance between the most protruding portion 104X1ap and the line L1 is too large, there is a problem that the wire cut has to be performed multiple times. For this reason, it is desirable that the separation distance is as close as possible to the width Wx1 of the convex portion and larger than the width Wx1. In the present embodiment, the separation distance between the most protruding portion 104X1ap and the line L1 is set so that the number of wire cuts is sufficient with one time.

[0084] The cutting of the intermediate product piece 602B is performed by wire electrical discharge machining. As shown in FIG. 19, the intermediate product piece 602B is moved toward the Wire1 which is a wire for wire electrical discharge machining, and is cut according to the line L1 of FIG. 18 by appropriately controlling the direction. As shown in FIG. 19, the wire electrical discharge machining is performed by overlapping a plurality of intermediate product pieces 602B. At this time, the positioning of the plurality of intermediate product pieces 602B is performed using the above-described positioning holes 602P. By passing an appropriate metal bar through the positioning holes 602P, the plurality of intermediate product pieces 602B can be positioned.

[0085] FIG. 20(a) is a view showing the final product piece 602BE after the wire cutting process is completed. The final product piece 602BE is cut along line L1. As is clear from a comparison between FIG. 18(b) and FIG. 20(b), by being cut along line L1, the width W1 in plan view of the intermediate shape 104X1 becomes smaller and becomes the width W2 of the final shape 104X2. As shown in FIGS. 18(b) and (c), the width W1 in plan view of the intermediate shape 104X1 is larger than the width (height) H1. On the other hand, as shown in FIGS. 20(b) and (c), the width W2 in plan view of the final shape 104X2 is smaller than the width (height) H1. Since the width (height) H1 is the thickness of the metal plate 600 (see FIG. 14), the width W2 in plan view of the final shape 104X2 is smaller than the thickness of the metal plate 600. Thereby, while setting the width (height) H1 in front view as the thickness of the metal plate 600, a plate-like shape can be realized.

[0086] Since wire electrical discharge machining is a non-contact machining method, residual stress does not occur. Also, since wire electrical discharge machining is performed in a liquid, thermal deformation is also minute. For this reason, in an extremely small plate-shaped handrail, deformation is a major problem both during and after machining, but such deformation can be avoided.

[0087] It is sold in the state of the final product piece 602BE, and the user cuts the final shape 104X2 of the plate-shaped handrail along line L2 in FIG. 20(a) and uses it as the plate-shaped handrail 104.

[0088] The advantages of the above manufacturing method are, firstly, that at the size of N gauge, it is possible to reproduce the shape with the actual reduced size. Secondly, compared with the case of only etching, the plate-like shape of the plate handrail can be expressed in a visible manner, and it is possible to distinguish it from the round bar handrail. Thirdly, for users, the same usage method as conventional handrail parts is possible, the difficulty level and the number of working hours do not increase, and no additional post-processing is required. Fourthly, different from the case of secondary processing of the plate handrail by users, uniform and homogeneous products can be mass-produced, and a uniform appearance as a model can be expected. Fifthly, it is a combination of a chemical treatment of wet etching and a non-contact treatment of wire electrical discharge machining, which is a dissolution treatment in liquid. Since the physical force applied to the metal plate as the material is minimized, problems such as deformation during processing and deformation due to residual stress after processing can be solved or reduced.

[0089] <Reference Example for Comparison with the Present Embodiment> FIG. 21 shows the case where paint is applied in the state of the intermediate shape 104X1 in FIG. 18 for comparison with the present embodiment. In the intermediate shape 104X1 in FIG. 21(a), since the front surface 104X1aa is also formed in a convex shape, it is visually recognized as a curved surface at the reduced scale of N gauge. As shown in FIG. 21(b), when the paint Pa is applied, the front surface 104X1aa is clearly visually recognized as a curved surface. As a result, as shown in FIG. 21(c), when light hits from above and in the front direction as indicated by the arrow X1, the lower half of the front surface 104X1aa becomes relatively dark and forms a shadow. On the other hand, as shown in FIG. 13(c) of the present embodiment, in the applied shape 104X3, the front surface 104X3a is flat, and no shadow is generated on the front surface 104X3a even when light hits from the direction of the arrow X1, so it can be recognized that it is plate-shaped.

[0090] Incidentally, it is theoretically possible to polish the convex shape of the front surface 104X1aa of the intermediate shape 104X1 to eliminate the convex shape. However, polishing is a process in a state of contact with the component, and since a physical force is applied to the fine component, there is a high possibility that the component will be damaged or deformed. Further, it is difficult to polish the convex front surface evenly, and it is difficult to finish the front surface 104X1aa flat.

[0091] Note that the present invention is not limited to this embodiment, and modifications, improvements, etc. within the scope that can achieve the object of the present invention are included in the present invention. For example, the configurations of the above-described first embodiment and second embodiment may be combined as appropriate.

Explanation of Signs

[0092] 100 Vehicle model 102, 104, 106 Plate-shaped handrail 104a Handrail main body part 104aa Front surface of the handrail main body 104ab Upper surface of the handrail main body 104ad Rear surface of the handrail main body 104b Connecting member 104ba Upper surface of the connecting member 104bb Side surface of the connecting member 104X1 Intermediate shape 104X2 Final shape 120 Shadow 300, 300A Actual vehicle 302, 304, 306, 308, 310, 312, 314, 316, 318, 320 Handrail 302A, 304A, 306A Plate-shaped handrail 420 Ideal plate-shaped handrail for model 420aa Front surface of the plate-shaped handrail 600 Metal plate RS Resist 602 Intermediate product 602A, 602B Intermediate product pieces 602BE Final product piece Wire 1 Wire for wire cutting Pa Paint

Claims

1. A handrail for a model, The handrail for a model has a plate-shaped handrail body and a connecting portion for connecting the handrail body and the model body, The handrail body and the connecting portion are integrally formed of metal, The connecting portion extends from the back surface of the handrail body, The handrail body is formed such that the width in the front view is larger than the width in the plan view, and the front surface visible in the front view is formed flat, The back surface of the handrail body and the side surface of the connecting portion are formed in a convex shape, At the boundary portion where the handrail body and the connecting portion are integrated, the convex shape of the back surface of the handrail body and the convex shape of the side surface of the connecting portion are integrally formed, When the handrail for a model is connected to the model body, a space is configured to exist between the back surface and the model body, Handrail for a model.

2. A manufacturing method of a handrail for a model having a plate-shaped handrail body and a connecting portion for connecting the handrail body and the model body, An etching step of forming an intermediate shape of the handrail for a model from a metal plate by etching, A wire cutting step of removing a part of the intermediate shape by wire cutting to form a final shape of the handrail for a model, having, In the etching step, the intermediate shape integrated in a manner in which the connecting portion extends from the back surface of the handrail body is formed, In the etching step, the upper surface and the bottom surface of the intermediate shape coincide with the upper surface and the bottom surface of the metal plate, and the surfaces other than the upper surface and the bottom surface of the intermediate shape coincide with the portions where etching progresses on the metal plate, In the etching step, the surfaces other than the upper surface and the bottom surface of the intermediate shape are formed in a convex shape, The width of the handrail main body in plan view in the intermediate shape is formed to be larger than the width (height) of the handrail main body in front view. In the wire cutting process, the convex portion formed on the front surface of the handrail main body is removed. In the final shape, the width (height) of the handrail main body in front view is formed to be larger than the width of the handrail main body in plan view. A method for manufacturing a model handrail.

3. In the wire cutting process, the handrail main body in the intermediate shape is cut on a surface biased toward the front side of the intermediate shape and parallel to the front surface in the final shape. The method for manufacturing a model handrail according to claim 2.

4. The difference in the width of the handrail main body in plan view in the intermediate shape and the width of the handrail main body in plan view in the final shape is not less than the width of the convex portion formed on the front surface of the handrail main body in the intermediate shape. The method for manufacturing a model handrail according to claim 2 or 3.

5. In the etching process, an intermediate product including a plurality of the intermediate shapes is formed. In the wire cutting process, a final product including a plurality of the final shapes is formed. The method for manufacturing a model handrail according to claim 2.

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