Processing device

Abstract

Provided are a cushion device capable of applying an appropriate pressing force to a workpiece while suppressing the size, and a processing device using the cushion device. 【Solution means】The cushion device CA includes a cushion member 1 that presses the workpiece W with a pressing force F2 in a direction opposite to the reaction force F3 while elastically absorbing the reaction force F3 from the workpiece W generated as the workpiece W is formed. The cushion member 1 is made of a carbon-based composite material. The processing device PA includes an outer shape 3 including an inner surface 31 that defines an internal space R including a forming chamber RA for the workpiece W, and a cushion device CA disposed in the internal space R. The cushion member 1 includes a first end surface 1a capable of pressing the workpiece W in a hot environment of the forming chamber RA and a second end surface 1b capable of contacting the inner surface 31 in the hot environment, and has a larger coefficient of thermal expansion than the outer shape 31.

Description

Technical Field

[0001] The present invention relates to a cushion device used when forming a workpiece, and a processing device using the cushion device.

Background Art

[0002] For example, when press-forming a workpiece cold or hot, a cushion device that elastically absorbs the reaction force from the workpiece may be used. As such a cushion device, spring cushions such as coil springs and leaf springs, gas cushions using pneumatic pressure (for example, Patent Document 1), or hydraulic cushions using hydraulic pressure (for example, Patent Document 2) are known.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] When forming a workpiece, if a relatively small pressing load suffices, a processing device can be configured with a conventional cushion device. However, in processing devices that require a pressing load in the range of several tens to several hundreds of tonf in the cold state and several to several hundreds of tonf in the hot state, the scale of the cushion device tends to become large, and device design can become difficult when there are restrictions on the installation space. Also, it has been difficult in some cases to apply an appropriate pressing force for forming to the workpiece while absorbing the reaction force. Furthermore, gas cushions and hydraulic cushions that can generate a large load cannot be used in a hot environment. For this reason, it is necessary to arrange these cushion devices in a cold environment and cause the cushion force to act on the workpiece via pins or the like, so the equipment inevitably becomes complicated.

[0005] An object of the present invention is to provide a cushion device capable of applying an appropriate pressing force to a workpiece while suppressing the size, and a processing device using the cushion device.

Means for Solving the Problems

[0006] A cushion device according to an aspect of the present invention 、 includes a cushion member that elastically absorbs the reaction force from the workpiece generated as the workpiece is formed, and presses the workpiece in a direction opposite to the direction in which the reaction force acts. The cushion member rod-shaped or cylindrical is made of a carbon-based composite material and presses the workpiece by thermal expansion force. The carbon-based composite material having elasticity to achieve elastic deformation and restoration to the original shape within a compression range of 25% or less of the total length is preferably a carbon fiber reinforced carbon composite material composed of, and presses the workpiece by the thermal expansion force and compression restoring force of the carbon fiber reinforced carbon composite It is desirable that

[0007] The inventor has found that the carbon-based composite material is a member rich in elasticity and can itself serve as a cushioning device. According to the above cushioning device, while absorbing the reaction force generated by the workpiece during forming, a required pressing force or compressive force can be applied to the workpiece. That is, an appropriate pressing force can be applied to the workpiece according to the magnitude of the reaction force. Further, since the carbon-based composite material itself becomes a cushioning member, it is easy to achieve a small size of the cushioning device. These functions become prominent when the carbon-based composite material is a carbon fiber reinforced carbon composite material.

[0008] The processing apparatus according to another aspect of the present invention includes an outer shape including an inner surface defining an internal space including a forming chamber in which a workpiece is formed, and the above-described cushioning device disposed in the internal space. The cushioning member includes a first end face capable of pressing the workpiece in a hot environment where the forming chamber is hot, and a second end face located on the side opposite to the first end face and capable of abutting on the inner surface of the outer shape in the hot environment. The coefficient of thermal expansion of the outer shape is set such that the first end face presses the workpiece and the second end face abuts on the inner surface of the outer shape.

[0009] According to this aspect, an appropriate pressing force can be applied to the workpiece in hot processing of the workpiece. The coefficient of thermal expansion of the cushioning member is selected such that in the hot state, the first end face presses the workpiece and the second end face abuts on the inner surface of the outer shape. In the hot state, the cushioning member thermally expands with the movement of the second end face restricted by the outer shape. Based on this thermal expansion, a pressing force can be applied to the workpiece from the first end face to compress and form the workpiece.

[0010] Here, the workpiece before forming generally has variations in dimensions in the compression direction. When the workpiece is larger than the reference dimension and is pressed by a member that only thermally expands, an excessive pressing force acts on the workpiece. In this case, it may cause damage to the outer shape or the workpiece. However, the cushion member can press the workpiece while elastically absorbing the reaction force from the workpiece. Therefore, when the workpiece is larger than the reference dimension and thus the reaction force becomes large, the cushion member suppresses the pressing force by the amount of the large reaction force and presses the workpiece. Accordingly, the cushion member can apply an appropriate pressing force to the workpiece during hot working. On the other hand, when the workpiece is smaller than the reference dimension, the reaction force received by the cushion member from the workpiece becomes small. In this case, the cushion member generates a large pressing force by the amount of the small reaction force due to thermal expansion, and thus can also apply an appropriate pressing force to the workpiece.

[0011] In the above processing apparatus, it is desirable that the cushion member has a larger coefficient of thermal expansion than at least the portion constituting the inner surface of the outer shape. According to this aspect, a pressing force can be applied to the workpiece from the first end face with a stronger force during hot working.

[0012] In the above processing apparatus, an inner mold disposed at least between the first end face and the workpiece and between the second end face and the inner surface may be further provided, and the inner mold may be set with a coefficient of thermal expansion so as to press the workpiece in the hot environment. In this case, it is desirable that the inner mold has a larger coefficient of thermal expansion than at least the portion constituting the inner surface of the outer shape.

[0013] According to this aspect, a structure is adopted in which an inner mold supported by a cushion member presses a workpiece. The inner mold has a coefficient of thermal expansion for pressing the workpiece in a hot environment. Preferably, the inner mold has a coefficient of thermal expansion larger than that of the inner surface portion of the outer mold. For this reason, the inner mold thermally expands in the hot state and applies a pressing force to the workpiece. As a result, the pressing force based on the thermal expansion of the two members, i.e., the cushion member and the inner mold, can be applied to the workpiece in the hot state. Therefore, it becomes easier to generate a required pressing force. Also, a hot press mechanism can be omitted.

[0014] In the above processing apparatus, the cushion member may include a first cushion member capable of pressing a first side surface of the workpiece and a second cushion member capable of pressing a second side surface intersecting the first side surface of the workpiece.

[0015] According to this aspect, the pressing force can be applied to the workpiece from two different directions by the two cushion members. That is, an appropriate pressing force corresponding to the reaction force can be applied to the first side surface and the second side surface of the workpiece that intersect each other.

[0016] In the above processing apparatus, the cushion member may further include a third cushion member capable of pressing a third side surface intersecting both the first side surface and the second side surface of the workpiece.

[0017] According to this aspect, an appropriate pressing force corresponding to the reaction force can be applied to the first side surface, the second side surface, and the third side surface of the workpiece that intersect each other.

[0018] A processing apparatus according to still another aspect of the present invention includes a working unit that performs pressing on a workpiece, and the above-described cushion device that is arranged to directly or indirectly press a portion of the workpiece other than the pressing region of the workpiece.

[0019] According to this aspect, the working unit can perform press working on the workpiece in a state where the workpiece is properly pressed by the cushion member with a pressing force corresponding to the reaction force of the workpiece. Therefore, the intended press working can be performed on the workpiece.

[0020] In the above processing apparatus, the working unit may be a punching die that performs punching on the workpiece, and the cushion device may be arranged to press a plate that contacts the workpiece around the area of the punching.

[0021] According to this aspect, the cushion device presses a plate that holds the workpiece during punching. When the working unit moves away from the workpiece after performing a punching operation on the workpiece, the cushion member that has elastically deformed by receiving the reaction force from the plate restores. Since this restoring force becomes the stripping force for peeling the punching tool from the workpiece, it can contribute to the realization of smooth punching.

[0022] In the above processing apparatus, the working unit may be a forging die that forges the workpiece, and the cushion device may be arranged to press a plate that contacts the workpiece around the area of the forging.

[0023] According to this aspect, the cushion device presses a plate that holds the workpiece during forging. Therefore, the workpiece can be pressed with an appropriate holding load during forging, and accurate forging can be realized.

[0024] In the above processing apparatus, the workpiece includes a first surface on which the press working is performed and a second surface opposite to the first surface, and the cushion device may be arranged to press the second surface.

[0025] According to this aspect, the cushion device can be utilized as a die cushion that absorbs the reaction force based on the warp of the workpiece during forging. Further, during press working, the cushion member can be elastically deformed in compression by the reaction force from the workpiece, and after the press working, the cushion member can be restored to its original shape. This restoring force can be utilized as a knockout force for pushing out the workpiece after press working from the mold.

Advantages of the Invention

[0026] According to the present invention, it is possible to provide a cushion device capable of applying an appropriate pressing force to a workpiece while suppressing the size, and a processing device using the cushion device.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

Figure 3

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Figure 8

Figure 9

Best Mode for Carrying Out the Invention

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The cushion device using the carbon-based composite material according to the present invention is applicable to various processing devices and other mechanical devices, and is not particularly limited in terms of use. Instead of cushion mechanisms such as springs, leaf springs, gas cushions using pneumatic pressure, and hydraulic cushions using hydraulic pressure that are currently applied to mechanical devices, the cushion device of the present invention can be applied. In particular, in mechanical devices that handle output loads in the range of 1 to several tens of tonf, the device configuration tends to become larger according to the conventional cushion mechanism, but the application of the cushion device of the present invention enables simplification and compactification of the device configuration. In addition, since the cushion performance of the conventional cushion mechanism changes, a design that avoids being exposed to a hot environment has been required, but the cushion device of the present invention can also be used in a hot environment.

[0029] The processing device according to the present invention is various mechanical devices to which the above cushion device can be applied. For example, as the processing device, hot forming dies for diffusion bonding, forging, or sintering a workpiece, cold forming dies such as for fine blanking or movable strips, press devices for performing hot pressing, punching, or blanking on a workpiece, a hydrostatic pressure generating device, a reaction force generating device, and the like can be exemplified.

[0030] [Cushion Device] FIG. 1 is a cross-sectional view showing a cushion device CA according to an embodiment of the present invention. The cushion device CA is a device used for processing a workpiece W, and includes a cushion member 1, a guide member 2, a sealing material 21, and a push block 22. The cushion member 1 has a rod-like shape such as a cylindrical shape or a prismatic shape. The cushion member 1 may have a cross-sectional shape with a different shape that enhances the effects of buckling prevention and surface pressure dispersion, or may be a cylindrical shape. When the cushion device CA moves relatively in the pressing direction PF, the cushion member 1 generates an applied pressing force F1 for pressing the workpiece W, and elastically absorbs the reaction force F3 from the workpiece W.

[0031] The guide member 2 is a cylindrical member that houses the cushion member 1 and prevents buckling of the cushion member 1. The sealing material 21 is fixedly attached so as to close one end opening of the guide member 2. One end of the cushion member 1 abuts against the sealing material 21. The push block 22 is disposed at the other end opening of the guide member 2 and is movable in the pressing direction PF. When the cushion device CA moves relatively in the pressing direction PF, the push block 22 abuts against the workpiece W and presses the workpiece W. The workpiece pressing force F2 generated by the push block 22 is the pressing force obtained by subtracting the reaction force F3 from the applied pressing force F1. The push block 22 has a flange-shaped base portion 22A, and the base portion 22A is adjacent to the other end of the cushion member 1. At the other end opening of the guide member 2, a push end plate 23 is disposed that allows the main body portion of the push block 22 to pass through while stopping the base portion 22A. The push end plate 23 is fixed to the opening edge of the guide member 2 by a push end pin 24.

[0032] From the viewpoint of the cushion function, it can be said that the cushion member 1 elastically absorbs the reaction force F3 from the workpiece W generated as the workpiece W is formed, and presses the workpiece W in the pressing direction PF opposite to the direction in which the reaction force F3 acts with the required workpiece pressing force F2. The cushion member 1 is made of a carbon-based composite material. Examples of the carbon-based composite material include carbon fiber reinforced carbon composite material and carbon fiber reinforced resin (CFRP). The carbon fiber reinforced carbon composite material is also referred to as a C / C composite material (Carbon Fiber Reinforced Carbon Composite). The C / C composite material may be impregnated with silicon carbide SiC. For CFRP, it is preferable to use those for high heat resistance applications. The carbon fibers include pitch-based and PAN-based.

[0033] The C / C composite material is a composite material obtained by molding carbon fibers and a binder resin at a high temperature and further performing a heat treatment for graphitization. The binder resin is, for example, a phenol resin or an epoxy resin. The cushion member 1 made of the C / C composite material is composed of a laminate of a plurality of fiber-containing layers 11, 12, 13,... having different fiber directions. For example, the first fiber-containing layer 11 has a fiber direction of 0°, the second fiber-containing layer 12 has a fiber direction of 45°, and the third fiber-containing layer 13 has a fiber direction of 90°. The fiber directions in which the long carbon fibers extend are different. Part or all of the fiber-containing layers 11, 12, 13,... may be fiber layers in which randomly arranged short carbon fibers are impregnated with resin, or may be fiber layers in which a woven fabric or a non-woven fabric of long carbon fibers is impregnated with resin. Also, the fiber-containing layers 11, 12, 13,... may contain air bubbles. The lamination direction of the fiber-containing layers 11, 12, 13,... is the pressing direction PF or the direction in which the cushion member 1 receives the reaction force F3.

[0034] The C / C composite material has anisotropy in mechanical properties. That is, it has high elasticity in the lamination direction of the fiber-containing layers 11, 12, 13,... and has high rigidity in the direction orthogonal to the lamination direction. According to the experiments of the present inventor, when a test of compressing the C / C composite material in the lamination direction was carried out, elasticity capable of achieving elastic deformation and restoration to the original shape was confirmed in a compression range of about 25% or less of the total length. The contribution of the air bubbles contained in the fiber layer is considered to achieve such high elasticity. For example, when compressing a rod-shaped member with a diameter of 15 mm and a length of 20 mm made of high-speed tool steel SKH51 with a Young's modulus of about 220 GPa, at the time of elastic deformation of 1% of the length, a surface pressure of about 224 kgf / mm 2 is generated. The compressive strength of the tool steel is about 220 kgf / mm 2Therefore, when considering repeated use, it is preferable to utilize an elastic range of about 0.5% with respect to the member length. However, with an elastic range of about 0.5%, since the area capable of absorbing the load is small, when using the tool steel as a cushion member, it can only be used under limited conditions. On the other hand, when a cylindrical body with a diameter of 15 mm and a length of 20 mm was fabricated using a C / C composite material and compressed in the stacking direction, it was confirmed that even when about 3% of the 20-mm length was repeatedly compressed, elastic return and load output (surface pressure generation) could be obtained. At about 3% compression, a surface pressure of about 4.8 kgf / mm 2 is generated, and it was confirmed that it has a high-load cushioning performance.

[0035] FIG. 2 is a cross-sectional view showing another example of the cushion device CA according to the present invention. The difference from the example of FIG. 1 is that the cushion member 1 is configured by laminating a plurality of cushion pieces 10 in the pressing direction PF. Each of the cushion pieces 10 is composed of a laminate of the above-described fiber-containing layers 11, 12, 13, ···. Adjacent cushion pieces 10 may be adhered with a thermosetting resin, or may simply be laminated within the guide member 2. A long C / C composite material in the pressing direction PF is relatively difficult to manufacture, and problems may occur in terms of quality and cost. In contrast, a short C / C composite material is relatively easy to manufacture and has the advantage of being excellent in terms of quality and cost. By forming the cushion member 1 into a laminated type of divided pieces (cushion pieces 10), the above advantages can be enjoyed.

[0036] [Description of Embodiment of Processing Apparatus] Hereinafter, with reference to FIGS. 3 to 8, various processing apparatuses to which the above-described cushion device CA is applied will be described.

[0037] <First Embodiment> FIG. 3 is a cross-sectional view showing a processing apparatus PA according to the first embodiment of the present invention. In FIG. 3, for convenience of explanation, the XY direction is indicated. The processing apparatus PA is an apparatus including a compression die for hot forming a workpiece W, and includes a cushion device CA including the above-described cushion member 1 and guide member 2, an outer die 3, a first inner die 41 and a second inner die 42, and a heating device (not shown). In a hot environment created by the heating device, the processing apparatus PA compresses and diffusion-bonds a workpiece W made of a laminate in which a plurality of plate materials WP are arranged in the X direction in the X direction. Note that the processing apparatus PA may use a forged product or sintering powder as the workpiece W.

[0038] The outer die 3 is made of, for example, cemented carbide, hot die steel, ceramics, or a carbon-based material, and has a shape of a rectangular frame that is long in the X direction. The outer die 3 has an inner surface 31 that defines an internal space R in which the workpiece W is formed. The internal space R is a rectangular parallelepiped space that is long in the X direction in plan view, with the +X side being the accommodation space of the cushion device CA and the -X side being the forming chamber RA of the workpiece W.

[0039] The cushion member 1 of the cushion device CA has a rod shape and is disposed in the internal space R in a state where it is surrounded by the guide member 2. The cushion member 1 is oriented such that the lamination direction of its fiber-containing layer is in the X direction. The coefficient of thermal expansion of the cushion member 1 is larger than that of the outer die 3. Note that it is sufficient if the coefficient of thermal expansion of the cushion member 1 is larger than at least the portion constituting the inner surface 31 of the outer die 3. The coefficient of thermal expansion of the C / C composite material in the lamination direction is about 8×10 -6 ~10×10 -6 / °C. Therefore, if a material that hardly thermally expands is selected as the constituent material of the outer die 3, the above requirements can be satisfied.

[0040] The first inner mold 41 and the second inner mold 42 are made of, for example, cemented carbide, hot die steel, ceramics, or carbon-based materials, and have a rectangular parallelepiped shape. The coefficient of thermal expansion of these inner molds 41 and 42 is also larger than that of the outer mold 3. Note that it is sufficient that the coefficient of thermal expansion of the inner molds 41 and 42 is larger than that of at least the portion constituting the inner surface 31 of the outer mold 3. The first inner mold 41, the second inner mold 42, and the inner surface 31 of the outer mold 3 define a forming chamber RA for the workpiece W. The first inner mold 41 forms the +X side surface of the forming chamber RA and is adjacent to the first end surface 1a on the -X side of the cushion member 1. The second end surface 1b on the +X side of the cushion member 1 is adjacent to the +X inner surface 31A of the inner surface 31. The second inner mold 42 forms the -X side surface of the forming chamber RA and is adjacent to the -X inner surface 31B. Here, "adjacent" includes not only the mode in which the first end surface 1a and the second end surface 1b always abut against each other with a press fit allowance, but also the mode in which there is a gap between them during cold working and they abut against each other during hot working.

[0041] The processing device PA does not include a mechanical mechanism for compressing the workpiece W, such as a hot press. Based on the difference in the coefficient of thermal expansion between the inner molds 41 and 42, the cushion member 1, and the outer mold 3, the workpiece W is brought into a press-fitted state between the inner molds 41 and 42 and diffusion bonded. When the forming chamber RA containing the workpiece W and its surroundings are brought into a hot environment by a heating device (not shown), the inner molds 41 and 42 thermally expand more than the outer mold, and the cushion member 1 and the workpiece W also thermally expand. Therefore, the workpiece W is brought into a press-fitted state and compressed. At this time, the second end surface 1b of the cushion member 1 abuts against the +X inner surface 31A of the outer mold 3 to be in a stop state, and the first end surface 1a is in a state of pressing the workpiece W via the first inner mold 41.

[0042] The cushion member 1 elastically absorbs the reaction force F3 from the workpiece W while applying a compressive force (pressing force F2 in FIG. 1) to the workpiece W. By this function, the cushion member 1 applies an appropriate compressive force to the workpiece W according to the magnitude of the reaction force F3. Therefore, the workpiece W made of a laminate of sheet materials WP can be properly diffusion bonded without causing problems such as poor forming due to insufficient compressive force or damage due to excessive compressive force.

[0043] The cushion member 1 is preferably incorporated between the first inner mold 41 and the +X inner surface 31A in a state of being pre-compressed in the X direction in the cold state. Thereby, in addition to the pressing force due to the thermal expansion of the inner molds 41 and 42 in the hot state, the pressing force due to the compression restoring force of the cushion member 1 can also act on the workpiece W. When a relatively large pressing force in the X direction can be generated based on the thermal expansion and compression restoring force of the cushion member 1, either one or both of the first inner mold 41 and the second inner mold 42 may be omitted. For example, it may be a mode in which the workpiece W is directly pressed by the first end face 1a of the cushion member 1.

[0044] Figs. 4(A) to (D) are cross-sectional views showing an example of the processing process of the workpiece W using the processing apparatus PA of the first embodiment. Fig. 4(A) shows the set state of the workpiece W in the cold state before diffusion bonding to the processing apparatus PA. Here, an example is shown in which the cushion member 1 is composed of two cushion pieces 10. As in the above-described desirable example, the cushion member 1 is incorporated between the first inner mold 41 and the +X inner surface 31A in a state of being elastically deformed by compression in the X direction. Therefore, the cushion member 1 generates a pressing force F11 that presses the +X inner surface 31A and a pressing force F12 that presses the first inner mold 41 based on compression elasticity in the cold state. The -X surface of the first inner mold 41 is in contact with the +X end face of the workpiece W. The +X surface of the second inner mold 42 is in contact with the workpiece W, and the -X surface is in contact with the -X inner surface 31B. When the compression allowance can be ensured by the thermal expansion of the inner molds 41 and 42, the inner molds 41 and 42 may be fitted with a gap.

[0045] Fig. 4(B) shows a state in which the processing apparatus PA is being heated, and Fig. 4(C) shows a state in which the processing apparatus PA has reached the hot forming temperature and the compression forces F21 and F22 are acting on the workpiece W. As described above, the outer mold 3 hardly expands thermally, but as indicated by the arrows in the figure, the inner molds 41 and 42, the cushion member 1, and the workpiece W expand thermally. Therefore, the workpiece W is compressed in the X direction. Since the +Y side surface and the -Y side surface of the workpiece W are in contact with the inner surface 31 of the outer mold 3, the arrangement state of the plate material WP does not get disturbed.

[0046] At this time, the cushion member 1 presses the workpiece W based on the thermal expansion force and the compression restoring force, and elastically absorbs the reaction force from the workpiece W. Generally, the workpiece W made of a laminate of plate materials WP has variations in dimensions in the compression direction (X direction). In the case of a workpiece W larger than the reference dimension, during hot working, the amount of compression of the workpiece W due to the thermal expansion of the inner molds 41 and 42 and the cushion member 1 becomes larger than the reference. That is, the compression allowance of the workpiece W becomes larger. If there is no cushioning effect, an excessive compression force may act on the workpiece W, causing damage to the workpiece W or the outer mold 3. However, in this embodiment, the reaction force corresponding to the excessive compression force on the workpiece W is absorbed by the cushion member 1. That is, when a reaction force exceeding the reference occurs from the workpiece W, the cushion member 1 is elastically compressed more than the reference by the amount of the excessive reaction force. Therefore, the compression forces F21 and F22 acting on the workpiece W can be set as reference values, and appropriate diffusion bonding can be achieved.

[0047] Conversely, in the case of a workpiece W smaller than the reference dimension, during hot working, the amount of compression of the workpiece W due to the thermal expansion of the inner molds 41 and 42 and the cushion member 1 becomes smaller than the reference. In this case, a situation may occur where the compression forces F21 and F22 are insufficient and the workpiece W cannot be sufficiently compressed. However, even in such a case, in this embodiment, the reaction force absorbed by the cushion member 1 only becomes smaller than the reference. That is, since the cushion member 1 applies a pressing force corresponding to the reaction force to the first inner mold 41, the compression forces F21 and F22 of the reference value can be applied to the workpiece W. Therefore, appropriate diffusion bonding can be achieved. As described above, the cushion member 1 made of a C / C composite material exhibits a compression force adjustment function of generating an appropriate compression force according to the dimensional variation of the workpiece W.

[0048] When hot forming in Fig. 4(C) is performed, the workpiece W will eventually soften, and the adjacent plate materials WP will be crimped together. Fig. 4(D) shows the state where the processing device PA has been cooled after hot forming. Due to the heat shrinkage based on the crimping and cooling, the dimension of the workpiece W in the X direction will decrease by Δd after the processing. Therefore, the cushion member 1 returns to the non-compressed state or the initial slightly press-fitted state. Also, the inner molds 41 and 42 and the workpiece W will be in a state of loosely contacting each other or a state where a gap is generated between them. Accordingly, the workpiece W can be easily taken out from the processing device PA.

[0049] In the above-described first embodiment, the case where the thermal expansion coefficients of the cushion member 1 and the inner molds 41 and 42 are larger than the thermal expansion coefficient of the outer mold 3 has been described. The relationship of the thermal expansion coefficients of the cushion member 1, the inner molds 41 and 42, and the outer mold 3 is not limited to the mode of the first embodiment. Even if the thermal expansion coefficients of the cushion member 1 and the inner molds 41 and 42 are set smaller than the thermal expansion coefficient of the outer mold 3, the workpiece W can be diffusion bonded. Two examples or less of diffusion bonding in such a setting are shown below.

[0050] First, the case of diffusion bonding the workpiece W with a relatively weak load will be described. In this case, the cushion member 1 is press-fitted slightly in advance. Since the restraining force of the outer mold 3 on the inner molds 41 and 42 during thermal expansion is weak, if the material types of the inner molds 41 and 42 and the outer mold 3 are appropriately selected, it is easy to make the thermal expansion amount of the inner molds 41 and 42 (the expansion amount in the stacking direction of the workpiece W) the same as the thermal expansion amount of the outer mold 3. Therefore, the load acting on the workpiece W during hot working becomes the same as the load acting on the workpiece W during cold working. That is, the load acting on the workpiece W during hot working becomes the load generated by the above-mentioned slight press-fitting, and diffusion bonding with a relatively weak load becomes possible. As an example of the workpiece W, oxygen-free copper that can be diffusion bonded with a relatively weak load can be mentioned. In this case, as the outer mold 3 used, hot die steel (thermal expansion coefficient 13×10 -6 / °C), and as the inner molds 41 and 42, cemented carbide (thermal expansion coefficient 5×10 -6 / °C) can be mentioned as an example. When oxygen-free copper is diffusion bonded at about 400°C, a C / C composite material is suitable as the cushion member 1.

[0051] Next, the case of diffusion bonding with the cushion member 1 pre-pressed will be described. The degree of pre-pressing is set as large as possible in consideration of the safety factor based on the compressive yield strength of the cushion member 1. In this case, by appropriately selecting the material types of the outer die 3 and the inner dies 41 and 42 so that the thermal expansion amount of the outer die 3 becomes larger than the thermal expansion amounts of the inner dies 41 and 42, the restraint force of the outer die 3 on the inner dies 41 and 42 can be weakened. As a result, the loads on the inner dies 41 and 42 and the cushion member 1 with respect to the workpiece W are released in the +X and -X directions opposite to the lamination direction. Therefore, even when the cushion member 1 is pre-pressed, an appropriate load can be applied to the workpiece W, and breakage of the workpiece W due to excessive compressive force can be prevented. As an example of the workpiece W, oxygen-free copper is also mentioned in this case. As the outer die 3 used, hot die steel is an example, and as the inner dies 41 and 42, cemented carbide is an example. When diffusion bonding oxygen-free copper at about 400°C, a C / C composite material is suitable as the cushion member 1.

[0052] Also, even when the thermal expansion coefficients of the inner dies 41 and 42 are equal to the thermal expansion coefficient of the outer die 3, that is, when they are of the same material type, diffusion bonding of the workpiece W is possible. In this case, by appropriately setting the dimensions of the inner dies 41 and 42 and the outer die 3 in the lamination direction X of the workpiece W, the expansion amounts of the inner dies 41 and 42 and the outer die 3 can be appropriately adjusted. Therefore, a desired load can be applied to the workpiece W.

[0053] FIG. 5 is a cross-sectional view showing a processing apparatus PAA according to a modified example of the first embodiment. This modified example is different from the first embodiment in that an overpressure prevention block 7 extending along the lamination direction of the workpiece W is disposed between the first inner mold 41 and the second inner mold 42. A gap G for determining the compression allowance of the workpiece W is formed between the +X end face of the overpressure prevention block 7 facing the first inner mold 41 and the -X end face of the first inner mold 41 facing the +X end face of the overpressure prevention block 7. When the cushion member 1 and the inner molds 41 and 42 thermally expand and compress the workpiece W by the amount of the gap G, the -X end face of the first inner mold 41 abuts against the +X end face of the overpressure prevention block. For this reason, the workpiece W is prevented from being compressed beyond the compression allowance. As a result, breakage due to excessive compressive force is prevented. Note that the gap G is shown exaggeratedly in the figure.

[0054] Also, although not shown, a surface pressure dispersion plate may be disposed along the inner surface 31 between the first end face 1a of the cushion member 1 and the inner surface 31 of the outer mold 3. When the cushion member 1 thermally expands and presses the inner surface 31, the surface pressure of the first end face 1a against the inner surface 31 increases. However, if the surface pressure dispersion plate is disposed, the surface pressure against the inner surface 31 can be reduced. By appropriately selecting the coefficient of thermal expansion of this surface pressure dispersion plate, it also acts as an inner mold that applies a load to the workpiece W in the -X direction.

[0055] Furthermore, although not shown, a plurality of cushion members 1 may be arranged in the Y direction, which is a direction orthogonal to the lamination direction of the workpiece W, to simultaneously diffusion bond a plurality of workpieces W. Also, a plurality of the inner molds 41 and 42 and the workpieces W may be arranged in the X direction, which is the lamination direction of the workpiece W, and pressed from the side of the inner mold 41 with one cushion member 1, or pressed with two cushion members disposed on both sides of the inner molds 41 and 42 for diffusion bonding. Further, a cushion member 1 may be disposed between the adjacent inner molds 41 and 42 of the arrangement for diffusion bonding.

[0056] <Second Embodiment> In the first embodiment, an example in which the cushion member 1 is arranged only on the side surface of the workpiece W in the X direction was shown. In the second embodiment, an example in which cushion members are arranged on the three side surfaces of the workpiece W in the XYZ directions is shown. Note that, as an aspect, cushion members may be arranged on any two of the three side surfaces.

[0057] FIG. 6(A) is a partially cut-away side view of the processing apparatus PA1 according to the second embodiment as viewed from the Z direction, and FIG. 6(B) is a side view of the processing apparatus PA in the X direction. The processing apparatus PA1 includes three cushion members: a first cushion member 1A, a second cushion member 1B, and a third cushion member 1C; an outer shape 30 corresponding to the outer shape 3 of the first embodiment; a first X plate 431 and a second X plate 432; a first Y plate 441 and a second Y plate 442; a first Z plate 451 and a second Z plate 452; and an outer guide 5.

[0058] The cushion members 1A, 1B, and 1C are rod-shaped members similar to the cushion member 1 described in the first embodiment, and have a function of elastically absorbing the reaction force from the workpiece W while applying a compressive force to the workpiece W. The first cushion member 1A extends in the X direction and can press the X side surface (first side surface) of the workpiece W. The second cushion member 1B extends in the Y direction and can press the Y side surface (second side surface) of the workpiece W. The third cushion member 1C extends in the Z direction and can press the Z side surface (third side surface) of the workpiece W. The outer shape 30 has the shape of a rectangular frame body and has a +X inner surface 31A, a -X inner surface 31B, a +Y inner surface 31C, and a -Y inner surface 31D that define an internal space R. The outer guide 5 is a rectangular frame body that surrounds the outer shape 30 in the YZ direction and has an inner surface 51 including a -Z inner surface 51A and a +Z inner surface 51B.

[0059] The six plates 431, 432, 441, 442, 451, 452 surrounding the workpiece W are members corresponding to the inner molds 41, 42 of the first embodiment, and are made of members that do not weld to the workpiece W during hot working. The six plates 431, 432, 441, 442, 451, 452 are arranged so as to surround the six side surfaces of the workpiece W, and define the forming chamber RA of the workpiece W. The first X plate 431 is adjacent to the +X side surface of the workpiece W, and the second X plate 432 is adjacent to the -X side surface. The -X end portion of the first cushion member 1A abuts against the +X side surface of the first X plate 431. The -X side surface of the second X plate 432 abuts against the -X inner surface 31B of the outer mold 30 and also serves as a load receiver.

[0060] The first Y plate 441 is adjacent to the +Y side surface of the workpiece W, and the second Y plate 442 is adjacent to the -Y side surface. The -Y end portion of the second cushion member 1B abuts against the +Y side surface of the first Y plate 441. The -Y side surface of the second Y plate 442 abuts against the -Y inner surface 31D of the outer mold 30. The first Z plate 451 is adjacent to the +Z side surface of the workpiece W, and the second Z plate 452 is adjacent to the -Z side surface. The -Z end portion of the third cushion member 1C abuts against the +Z side surface of the first Z plate 451. The -Z side surface of the second Z plate 452 abuts against the -Z inner surface 51A of the outer guide 5.

[0061] A first load receiving plate 46 for receiving the abutting load of the first cushion member 1A is disposed between the +X end portion of the first cushion member 1A and the +X inner surface 31A of the outer mold 30. Similarly, a second load receiving plate 47 is disposed between the +Y end portion of the second cushion member 1B and the +Y inner surface 31C of the outer mold 30, and a third load receiving plate 48 is disposed between the +Z end portion of the third cushion member 1C and the +Z inner surface 51B of the outer guide 5.

[0062] The desirable relationships of the coefficients of thermal expansion among the members constituting the processing device PA1 are as follows. Let the coefficients of thermal expansion of the outer shape 30 and the outer guide 5 be α1 and α2, respectively. Also, let the coefficients of thermal expansion of the first cushion member 1A, the second cushion member 1B, and the third cushion member 1C be β1, β2, and β3, respectively. Let the coefficient of thermal expansion of the six plates 431, 432, 441, 442, 451, 452 surrounding the workpiece W be γ, and let the coefficient of thermal expansion of the three load-receiving plates 46, 47, 48 be δ. In this case, α1 < β1, α1 < β2, α2 < β3 α1 < γ, α1 < δ, α2 < γ, α2 < δ it is desirable to satisfy the relationships of.

[0063] If the above relationships of the coefficients of thermal expansion are satisfied, based on the thermal expansion differences between the outer shape 30 and the outer guide 5 and the cushion members 1A, 1B, 1C, plates 431, 432, 441, 442, 451, 452, and load-receiving plates 46, 47, 48 disposed inside them, the workpiece W can be compression-molded hot without using a hot press or the like. If the cushion members 1A, 1B, 1C are incorporated in a pre-compressed state, the workpiece W can be compressed by superimposing their compression restoring forces on the thermal expansion forces. If the compression force is insufficient, a hot press may be additionally used to assist in the compression of the workpiece W. For example, a structure can be adopted in which the outer guide 5, the third cushion member 1C, and the third load-receiving plate 48 are removed, and the first Z-plate 451 is directly pressed by a hot press.

[0064] According to the second embodiment, while the cushion members 1A, 1B, 1C apply pressing forces in the -X direction, -Y direction, and -Z direction to the workpiece W, respectively, they elastically absorb the reaction forces in the +X direction, +Y direction, and +Z direction from the workpiece W. That is, appropriate pressing forces corresponding to the reaction forces can be applied to each side surface of the workpiece W in the XYZ directions. Therefore, the six side surfaces of the workpiece W can be accurately formed, and damage to the workpiece W and the mold can be prevented.

[0065] <The Third Embodiment> In the third embodiment, as well as the fourth and fifth embodiments described below, a processing apparatus including a working unit that performs pressing on a workpiece is exemplified. The cushion apparatus CA is arranged to directly or indirectly press a portion of the workpiece other than the pressing region. In each embodiment, the cushion apparatus CA is arranged such that the working unit can perform pressing on the workpiece while the workpiece is properly pressed by the cushion member 1 with a pressing force corresponding to the reaction force from the workpiece. By arranging the cushion apparatus CA, it becomes possible to perform the intended pressing on the workpiece.

[0066] FIG. 7 is a side sectional view of a punching apparatus PA2, which is a third embodiment of the processing apparatus according to the present invention. The up / down / left / right direction indications attached to FIG. 7 are for convenience of explanation and do not limit the usage direction of the punching apparatus PA2. In the punching apparatus PA2, the working unit that performs pressing is a punch 6 that can move up and down, and the workpiece is a punched plate WA. The punching apparatus PA2 is an apparatus capable of performing fine blanking processing utilizing the hydrostatic pressure effect. When the punch 6 descends toward the punched plate WA whose upper and lower surfaces are constrained, the tip 6T of the punch 6 penetrates the punched plate WA from the vertical direction, and a punched piece WAT is punched out. After punching, the punch 6 moves up.

[0067] The punching apparatus PA2 includes a first cushion apparatus CA1 and a second cushion apparatus CA2 as a pressing mechanism for holding the punched plate WA during punching. Further, the punching apparatus PA2 includes, as a punching mechanism by the punch 6, a yokan plate 61, an upper bed 62, an upper backing plate 63, a punch plate 64, a stripper plate 65 (a plate that contacts the workpiece), a die plate 66, a lower backing plate 67, and a lower bed 68.

[0068] The first cushion device CA1 and the second cushion device CA2 have the same configuration as the cushion device CA shown in FIG. 1, and are arranged in a pair on the left and right sides with the punch 6 sandwiched therebetween. The cushion devices CA1 and CA2 include a cushion member 1 and a push block 22 disposed on the lower end side of the cushion member 1. The yokan plate 61 is a pedestal that positions and holds the upper end portions of the pair of cushion devices CA1 and CA2. The upper bed 62 is given a driving force that moves up and down during the punching operation. The upper backing plate 63 is a plate against which the upper end of the punch 6 abuts. The punch plate 64 has a mounting hole for the punch 6 and holds the punch 6. The yokan plate 61, the upper backing plate 63, and the punch plate 64 that holds the punch 6 are supported by the upper bed 62, and when the upper bed 62 moves up and down, these members also move up and down integrally.

[0069] The stripper plate 65 is disposed so as to abut on the upper surface of the plate WA to be punched. The stripper plate 65 has a through hole through which the punch 6 passes and an annular protrusion that bites into the upper surface of the plate WA. The die plate 66 is disposed so as to abut on the lower surface of the plate WA and presses the plate WA from the lower surface side in the reverse direction. The lower backing plate 67 is disposed on the lower surface of the die plate 66. The lower bed 68 is a fixed pedestal that supports the lower backing plate 67 and the die plate 66. A punching hole 6H is drilled so as to penetrate the die plate 66, the lower backing plate 67, and the lower bed 68 in the vertical direction. The punched piece WAT is recovered through the punching hole 6H.

[0070] The punched plate WA is sandwiched between a stripper plate 65 and a die plate 66 and is punched by a punch while the upper and lower surfaces are restrained. Thereby, the punched piece WAT can be sheared from the punched plate WA. When the upper bed 62 descends, the push blocks 22 of the cushion devices CA1 and CA2 abut against the stripper plate 65, thereby pressing the plate WA. That is, the stripper plate 65 is in contact with the plate WA around the punching area. The cushion devices CA1 and CA2 generate a pressing force F2 for pressing the stripper plate 65.

[0071] The push block 22 abuts against the stripper plate 65 before the tip 6T of the punch 6 contacts the plate WA, and applies the pressing force F2 during the punching operation and the drawing operation of the punch 6. That is, when the push block 22 abuts against the stripper plate 65, the cushion member 1 is elastically deformed in compression, generating the pressing force F2. The length between LV1 and LV2 noted in FIG. 6 corresponds to the maximum compression allowance of the cushion member 1. The cushion member 1 applies the pressing force F2 to the stripper plate 65 via the push block 22, and elastically absorbs the reaction force from the stripper plate 65. That is, the cushion member 1 can apply an appropriate pressing force F2 to the stripper plate 65 according to the reaction force.

[0072] The pressing force F2 of the cushion member 1 is also used as the stripping force for peeling the punched piece WAT from the punch 6 after the punching operation. After the punching operation, the punch 6 also rises as the upper bed 62 rises. At this time, an event may occur in which the punched piece WAT bites into the tip 6T and cannot be peeled off. However, in the present embodiment, even when the punch 6 rises, the push block 22 continues to hold down the stripper plate 65 for a period corresponding to the length of the above-mentioned compression allowance. That is, the cushion member 1 that has undergone compression elastic deformation under the reaction force from the stripper plate 65 is restored as the upper bed 62 rises, and the stripper plate 65 is held down by the pressing force F2 based on this restoring force. This pressing force F2 becomes the stripping force for peeling the punched piece WAT from the workpiece plate WA to be punched. Therefore, the stripability of the punched piece WAT from the punch 6 is improved.

[0073] <Fourth Embodiment> FIG. 8 is a side sectional view of a forging forming apparatus PA3, which is a fourth embodiment of the processing apparatus according to the present invention. The working part that performs press working in the forging forming apparatus PA3 is a forging punch 6A that can move up and down, and the workpiece is a forging WB to be forged. The lower surface (second surface) of the forging WB is supported by a push-back pin 60. When the forging punch 6A is lowered toward the forging WB, the tip 6AT of the forging punch 6A hits the upper surface (first surface) of the forging WB from the vertical direction, and the forging WB is forged into the required shape. After the forging forming, the forging punch 6A is raised.

[0074] The forging forming apparatus PA3 includes a first cushion device CA1, a second cushion device CA2, a yokan plate 61, an upper bed 62, an upper backing plate 63, a punch plate 64, a die plate 66, and a lower backing plate 67, which are the same as those of the punching apparatus PA2 of the third embodiment. The punch plate 64 holds the forging punch 6A described above. A third cushion device CA3 is provided on a lower bed 68A that supports the die plate 66 and the lower backing plate 67. The third cushion device CA3 includes a guide hole 68H that extends in the vertical direction and is formed in the lower bed 68A, and a cushion member 1 accommodated in the guide hole 68H. The cushion member 1 supports the push-back pin 60 from below and functions as a die cushion.

[0075] A holding plate 69 having a through hole of the forging punch 6A is disposed between the punch plate 64 and the die plate 66. The holding plate 69 is a plate that holds the forged workpiece WB during forging forming, and abuts against the upper surface of the forged workpiece WB around the forging forming region. The holding plate 69 is applied with a pressing force F2 when the push blocks 22 of the pair of left and right cushion devices CA1 and CA2 abut against it as the upper bed 62 descends. On the other hand, a push-back force F4 generated by the third cushion device CA3 is applied to the lower surface of the forged workpiece WB via the push-back pin 60.

[0076] The push blocks 22 of the cushion devices CA1 and CA2 abut against the holding plate 69 before the tip 6AT of the forging punch 6A abuts against the forged workpiece WB, and apply the pressing force F2 during the shaping of the forged workpiece WB by the forging punch 6A and during the pulling-out operation after shaping. That is, when the push block 22 abuts against the holding plate 69, the cushion member 1 is elastically deformed in compression, generating the pressing force F2. The cushion member 1 elastically absorbs the reaction force from the holding plate 69 while applying the pressing force F2 to the holding plate 69. That is, the cushion member 1 can apply an appropriate pressing force F2 to the holding plate 69 according to the reaction force. Therefore, accurate forging forming can be realized.

[0077] When the forging WB is pressed downward by the forging punch 6A, a part of the forging WB enters the escape hole of the die plate 66. As a result, the push-back pin 60 in contact with the lower surface of the forging WB is pushed downward, and the cushion member 1 of the third cushion device CA3 is also compressed. The cushion member 1 generates a push-back force F4 that elastically absorbs the reaction force from the push-back pin 60 and pushes the push-back pin 60 upward. Further, even after the forging punch 6A separates from the forging WB and rises, based on the restoring force of the cushion member 1 that has been elastically compressed and deformed under the reaction force, the push-back force F4 continuously acts on the push-back pin 60. This restoring force can be utilized as a knockout force for pushing out the forging WB after forging from the die plate 66. Therefore, the removability of the forging WB after forging can be improved.

[0078] <Fifth Embodiment> FIG. 9 is a side sectional view of a forging forming apparatus PA4, which is a fifth embodiment of a processing apparatus according to the present invention. The working part that performs press working in the forging forming apparatus PA4 is a forging punch 6B that can move up and down, and the workpiece is a forging WC to be forged. When the forging punch 6B is lowered toward the forging WC, the tip 6BT of the forging punch 6B hits the upper surface of the forging WC from the vertical direction, and the forging WC is forged into a required shape. After forging, the forging punch 6B is raised.

[0079] The forging forming apparatus PA4 includes an upper bed 62, an upper backing plate 63, a punch plate 64, a die plate 66, a lower backing plate 67, and a lower bed 68. As a cushion mechanism, the forging forming apparatus PA4 includes a cushion device CA (simplified in FIG. 9) similar to that in FIG. 1. As the upper bed 62 descends, the forging punch 6B forges the forging WC placed on the die plate 66. FIG. 9 shows an example in which the vicinity of the right end of the forging WC is being pressed by the tip 6BT of the forging punch 6B.

[0080] The cushion device CA directly presses the upper left surface of the forging WC with a pressing force F2. While applying the pressing force F2 to the forging WC, the cushion device CA elastically absorbs the reaction force from the forging WC. That is, the forging WC is pressed with an appropriate pressing force F2 corresponding to the reaction force. Therefore, it is possible to suppress the occurrence of processing defects caused by an excessive or insufficient pressing load on the forging WC.

Explanation of Signs

[0081] 1 Cushion member 1a, 1b First end face, second end face 2 Guide member 3, 30 Outer shape 41 First inner shape 42 Second inner shape 5 Outer guide 6 Punch (working part) 6A Forging punch (working part / forging die) 65 Stripper plate (plate contacting the workpiece) 69 Pressing plate (plate contacting the workpiece) CA Cushion device CA1, CA2, CA3 First, second, third cushion devices PA Processing device PA1 Punching processing device (processing device) PA2, PA3, PA4 Forging and forming processing devices (processing devices) R Internal space RA Forming chamber W Workpiece WA Punched plate (workpiece) WB, WC Forgings (workpieces)

Claims

1. an outer mold including an inner surface defining an interior space including a molding chamber in which a workpiece is molded; A cushion device disposed in the internal space, The cushion device is a cushion member that elastically absorbs a reaction force from the workpiece generated in association with the forming of the workpiece and presses the workpiece in a direction opposite to the direction in which the reaction force acts; The cushion member is A rod-shaped or tubular carbon matrix composite material is used to press the workpiece by thermal expansion force, a first end surface capable of pressing a workpiece in a hot environment in the forming chamber; a second end surface located opposite the first end surface and capable of contacting an inner surface of the outer mold in the hot environment; a thermal expansion coefficient of the outer mold is set so that the first end surface presses against a workpiece and the second end surface abuts against the inner surface of the outer mold.

2. In the processing apparatus according to claim 1, The cushion member has a thermal expansion coefficient greater than that of at least a portion constituting the inner surface of the outer mold.

3. In the processing apparatus according to claim 1 or 2, Further, an inner mold is disposed between the first end surface and the workpiece and / or between the second end surface and the inner surface, A processing device, wherein the inner mold has a thermal expansion coefficient set so as to press the workpiece in the hot environment.

4. In the processing apparatus according to claim 3, A processing apparatus, wherein the inner mold has a thermal expansion coefficient greater than that of at least a portion constituting the inner surface of the outer mold.

5. In the processing apparatus according to claim 1 or 2, The processing device, wherein the cushion member includes a first cushion member capable of pressing a first side surface of the workpiece, and a second cushion member capable of pressing a second side surface of the workpiece that intersects with the first side surface.

6. In the processing apparatus according to claim 5, The processing apparatus, wherein the cushion member further includes a third cushion member capable of pressing a third side surface of the workpiece that intersects with both the first side surface and the second side surface.

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