Machining apparatus

Abstract

To provide a cushion device capable of applying proper pressing force to a workpiece while suppressing the size, and a processing device using the cushion device.SOLUTION: A cushion device CA includes a cushion member 1 which presses a workpiece W with a pressing force F3 in a direction opposite to a reactive force F3 while elastically absorbing the reactive force F2 from the workpiece W generated with the forming of the workpiece W. The cushion member 1 is made of a carbon-based composite material. A processing device PA includes an outer mold 3 including an inner surface 31 defining an internal space R including a molding chamber RA of a workpiece W, and a cushion device CA arranged in the internal space R. The cushion member 1 includes a first end surface 1a capable of pressing the workpiece W in the hot condition of the forming chamber RA and a second end surface 1b capable of abutting on the inner surface 31 in the hot condition, and has a thermal expansion coefficient larger than that of the outer die 31.SELECTED DRAWING: Figure 3

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 technology]

[0002] For example, when cold or hot press-forming a workpiece, a cushion device that elastically absorbs the reaction force from the workpiece is sometimes used. Known cushion devices include spring cushions such as coil springs and leaf springs, gas cushions that use air pressure (e.g., Patent Document 1), and hydraulic cushions that use hydraulic pressure (e.g., Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 7-241625 [Patent Document 2] Japanese Patent Application Publication No. 64-57927 Summary of the Invention [Problem to be solved by the invention]

[0004] When a relatively small press load is required to form the workpiece, conventional cushion devices can be used to construct the processing equipment. However, for processing equipment requiring press loads of tens to hundreds of tonf in cold processing and several tons to hundreds of tonf in hot processing, the cushion device tends to be large, which can make device design difficult when installation space is limited. It can also be difficult to apply the appropriate pressing force to the workpiece while absorbing the reaction force. Furthermore, gas cushions and hydraulic cushions, which can generate large loads, cannot be used in hot processing. Therefore, these cushion devices must be placed in a cold environment and their cushion force must be applied to the workpiece via pins or other devices, which inevitably complicates the equipment.

[0005] An object of the present invention is to provide a cushion device that can apply an appropriate pressing force to a workpiece while keeping its size small, and a processing device that uses the cushion device. [Means for solving the problem]

[0006] A cushion device according to one aspect of the present invention includes a cushion member that elastically absorbs a reaction force from a workpiece that occurs during forming of the workpiece, regardless of whether the workpiece is in a cold environment or a hot environment, and presses the workpiece in a direction opposite to the direction in which the reaction force acts, the cushion member being made of a carbon-based composite material. The carbon-based composite material is preferably a carbon fiber-reinforced carbon composite material.

[0007] The inventors have discovered that carbon-based composite materials are highly elastic and can function as a cushioning device by themselves. The cushioning device described above can apply a required pressing or compressive force to a workpiece while absorbing the reaction force generated by the workpiece during molding. In other words, an appropriate pressing force can be applied to the workpiece depending on the magnitude of the reaction force. Furthermore, because the carbon-based composite material itself serves as a cushioning member, it is easy to achieve a small cushioning device. These functions are particularly pronounced when the carbon-based composite material is a carbon fiber-reinforced carbon composite.

[0008] A processing apparatus according to another aspect of the present invention comprises an outer mold including an inner surface that defines an internal space including a molding chamber in which the workpiece is molded, and the above-mentioned cushion device that is arranged in the internal space, wherein the cushion member includes a first end face that can press the workpiece in a hot environment in which the molding chamber is hot, and a second end face that is located opposite the first end face and can abut against the inner surface of the outer mold in the hot environment, and the thermal expansion coefficient of the outer mold is set so that the first end face presses the workpiece and the second end face abuts against the inner surface of the outer mold.

[0009] According to this aspect, an appropriate pressing force can be applied to the workpiece during hot working of the workpiece. The thermal expansion coefficient of the cushion member is selected so that the first end face presses the workpiece during hot working and the second end face abuts against the inner surface of the outer mold. During hot working, the cushion member thermally expands while the movement of the second end face is restricted by the outer mold. Based on this thermal expansion, a pressing force can be applied to the workpiece from the first end face, and the workpiece can be compression molded.

[0010] Here, workpieces before forming generally have dimensional variations in the compression direction. If the workpiece is larger than the standard dimensions, pressing it with a thermally expandable member would result in excessive pressing force acting on the workpiece. This could potentially cause damage to the outer mold or the workpiece. However, the cushion member can elastically absorb the reaction force from the workpiece while pressing it. Therefore, if the workpiece is larger than the standard dimensions and therefore the reaction force is large, the cushion member reduces the pressing force by the amount of the larger reaction force and presses the workpiece. Therefore, the cushion member can apply an appropriate pressing force to the workpiece during hot forming. On the other hand, if the workpiece is smaller than the standard dimensions, the reaction force received by the cushion member from the workpiece is smaller. In this case, the cushion member generates a pressing force greater by the amount of the smaller reaction force due to thermal expansion, thereby applying an appropriate pressing force to the workpiece.

[0011] In the processing apparatus, it is desirable that the cushion member has a thermal expansion coefficient greater than that of at least the portion of the outer mold that constitutes the inner surface. According to this aspect, a stronger pressing force can be applied to the workpiece from the first end face in a hot state.

[0012] The processing apparatus may further include an inner mold disposed between the first end surface and the workpiece or between the second end surface and the inner surface, the inner mold having a thermal expansion coefficient set to press the workpiece in the hot environment. In this case, it is desirable that the inner mold have a thermal expansion coefficient greater than that of at least a portion of the outer mold constituting the inner surface.

[0013] According to this embodiment, the inner mold supported by the cushion member presses the workpiece. The inner mold has a thermal expansion coefficient that presses the workpiece in a hot environment. Preferably, the inner mold has a thermal expansion coefficient greater than that of the inner surface of the outer mold. Therefore, the inner mold thermally expands in the hot environment and applies a pressing force to the workpiece. As a result, a pressing force based on the thermal expansion of the two members, the cushion member and the inner mold, can be applied to the workpiece in the hot environment. Therefore, it is easier to generate the required pressing force. Furthermore, a hot press mechanism can be omitted.

[0014] In the above processing device, 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 of the workpiece that intersects with the first side surface.

[0015] According to this aspect, the two cushion members can apply a pressing force to the workpiece from two different directions, i.e., an appropriate pressing force according to the reaction force can be applied to the first and second intersecting side surfaces of the workpiece.

[0016] In the above processing device, the cushion member may further include 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.

[0017] According to this embodiment, an appropriate pressing force according 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 with one another.

[0018] A processing device according to yet another aspect of the present invention comprises a working unit that applies press processing to a workpiece, and the above-described cushion device that is positioned to directly or indirectly press a portion of the workpiece other than the area that is being press processed.

[0019] According to this aspect, the working unit can press the workpiece while the cushion member is pressing the workpiece with an appropriate pressing force corresponding to the reaction force of the workpiece, thereby enabling the desired press working to be performed on the workpiece.

[0020] In the above-mentioned processing device, the working unit may be a punching die that performs punching on the workpiece, and the cushioning device may be arranged to press a plate that abuts against the workpiece around the punching area.

[0021] According to this aspect, the cushion device presses the plate that holds down the workpiece during punching. When the working unit performs a punching operation on the workpiece and then moves away from the workpiece, the cushion member elastically deforms due to the reaction force from the plate and returns to its original shape. This restoring force acts as a stripping force that peels the punching tool off the workpiece, contributing to the realization of smooth punching.

[0022] In the above-mentioned processing device, the working part may be a forging die for forging the workpiece, and the cushion device may be arranged to press a plate that abuts against the workpiece around the forging area.

[0023] According to this aspect, the cushion device presses the plate that presses the workpiece during forging, thereby allowing the workpiece to be pressed with an appropriate pressing load during forging, thereby achieving highly accurate forging.

[0024] In the above processing device, the workpiece may include a first surface on which the press processing is performed and a second surface opposite 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 used as a die cushion that absorbs the reaction force due to the warpage of the workpiece during forging. Furthermore, the cushion member can be compressively elastically deformed by the reaction force from the workpiece during press forming, and can be restored to its original shape after press forming. This restoring force can be used as a knockout force that pushes the workpiece out of the die after press forming. [Effects of the Invention]

[0026] According to the present invention, it is possible to provide a cushion device that can apply an appropriate pressing force to a workpiece while suppressing its size, and a processing device that uses the cushion device. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. 1 is a cross-sectional view showing an example of a cushion device according to the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing another example of the cushion device according to the present invention. [Figure 3] FIG. 3 is a cross-sectional view showing a first embodiment of a processing device according to the present invention. [Figure 4] 4(A) to 4(D) are cross-sectional views showing the machining process of a workpiece using the machining device of the first embodiment. [Figure 5] FIG. 5 is a cross-sectional view showing a modification of the processing device of the first embodiment. [Figure 6]FIG. 6(A) is a partially cutaway side view of a processing device according to a second embodiment as seen from the Z direction, and FIG. 6(B) is a side view of the processing device as seen from the X direction. [Figure 7] FIG. 7 is a side cross-sectional view of a punching device, which is a third embodiment of the processing device according to the present invention. [Figure 8] FIG. 8 is a side cross-sectional view of a forging apparatus, which is a fourth embodiment of the processing apparatus according to the present invention. [Figure 9] FIG. 9 is a side cross-sectional view of a forging apparatus, which is a fifth embodiment of the processing apparatus according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] An embodiment of the present invention will be described in detail below with reference to the drawings. A cushioning device using a carbon-based composite material according to the present invention can be applied to various processing equipment and other machinery and devices, and its use is not particularly limited. The cushioning device of the present invention can be used in place of cushioning mechanisms currently used in machinery and devices, such as springs, leaf springs, gas cushions using air pressure, and hydraulic cushions using hydraulic pressure. In particular, for machinery and devices that handle output loads of one to several tens of tonf, conventional cushioning mechanisms tend to result in large device configurations, but application of the cushioning device of the present invention makes it possible to simplify and compact the device configuration. Furthermore, conventional cushioning mechanisms require designs that avoid exposure to hot environments due to changes in cushioning performance, but the cushioning device of the present invention can also be used in hot environments.

[0029] The processing apparatus according to the present invention is a variety of mechanical devices to which the cushion device can be applied, including, for example, hot forming dies for diffusion bonding, forging, or sintering workpieces, cold forming dies for fine blanking or movable strips, presses for hot pressing, blanking, or punching workpieces, hydrostatic pressure generators, and reaction force generators.

[0030] [Cushioning device] FIG. 1 is a cross-sectional view showing a cushion device CA according to one embodiment of the present invention. The cushion device CA is used to process a workpiece W and includes a cushion member 1, a guide member 2, a sealing member 21, and a push block 22. The cushion member 1 has a rod-like shape, such as a cylindrical or prismatic shape. The cushion member 1 may have an irregular cross-sectional shape or may be cylindrical, which enhances the effects of preventing buckling and dispersing surface pressure. When the cushion device CA moves relative to the workpiece W in the pressing direction PF, the cushion member 1 generates an applied pressing force F1 that presses the workpiece W, while elastically absorbing a reaction force F3 from the workpiece W.

[0031] The guide member 2 is a cylindrical member that houses the cushion member 1 and prevents the cushion member 1 from buckling. A sealing material 21 is fixedly attached to one end opening of the guide member 2 so as to block it. One end of the cushion member 1 abuts against the sealing material 21. A 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 22A, which is adjacent to the other end of the cushion member 1. A push end plate 23 is disposed at the other end opening of the guide member 2, which passes through the main body of the push block 22 and abuts against the base 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 cushioning function, the cushion member 1 elastically absorbs the reaction force F3 from the workpiece W generated during the forming of the workpiece W, while pressing the workpiece W with the required workpiece pressing force F2 in the pressing direction PF opposite to the direction in which the reaction force F3 acts. The cushion member 1 is made of a carbon-based composite material. Examples of carbon-based composite materials include carbon fiber reinforced carbon composite materials and carbon fiber reinforced plastics (CFRP). Carbon fiber reinforced carbon composite materials are also called C / C composite materials (Carbon Fiber Reinforced Carbon Composites). C / C composite materials may be impregnated with silicon carbide (SiC). It is preferable to use CFRP for high heat resistance applications. Carbon fibers include pitch-based and PAN-based carbon fibers.

[0033] A C / C composite material is a composite material obtained by molding carbon fibers and a binder resin at high temperatures and then heat-treating them for graphitization. Examples of binder resins include phenolic resin and epoxy resin. The cushion member 1 made of a C / C composite material is composed of a laminate of multiple fiber-containing layers 11, 12, 13, etc., each with a different fiber direction. 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-containing layers 11, 12, 13, etc. may all or some of them be fiber layers formed by impregnating randomly oriented short carbon fibers with resin, or may be fiber layers formed by impregnating a woven or nonwoven fabric of long carbon fibers with resin. The fiber-containing layers 11, 12, 13, etc. may contain air bubbles. The stacking 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] C / C composite materials have anisotropic mechanical properties. That is, they have high elasticity in the lamination direction of the fiber-containing layers 11, 12, 13, etc., and high rigidity in the direction perpendicular to the lamination direction. According to experiments conducted by the inventors, when a C / C composite material was compressed in the lamination direction, it was confirmed that it had the elasticity to achieve elastic deformation and restoration to its original shape within a compression range of approximately 25% or less of its total length. The contribution of the bubbles contained in the fiber layers to achieving such high elasticity is believed to be the contribution of the bubbles contained in the fiber layers. For example, when 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 approximately 220 GPa is compressed, it has a stiffness of approximately 224 kgf / mm at the point of elastic deformation of 1% of its length. 2 The tool steel has a compressive strength of approximately 220 kgf / mm 2 Therefore, when considering repeated use, it is preferable to utilize an elastic range of about 0.5% of the component length. However, with an elastic range of about 0.5%, the area that can absorb load is small, so when using this tool steel as a cushion component, it can only be used under limited conditions. On the other hand, when a cylindrical body of 15 mm diameter and 20 mm length was manufactured using C / C composite material and compressed in the lamination direction, it was confirmed that elastic recovery and load output (generated surface pressure) were obtained even when repeatedly compressed by about 3% of the 20 mm length. At a compression of about 3%, the force was about 4.8 kgf / mm 2 This means that a surface pressure of 1000 psi is generated, and it has been confirmed that the product has high load cushioning performance.

[0035] FIG. 2 is a cross-sectional view showing another example of a cushion device CA according to the present invention. The difference from the example in FIG. 1 is that the cushion member 1 is configured by stacking multiple cushion pieces 10 in the pressing direction PF. Each cushion piece 10 is made of a laminate of the above-described fiber-containing layers 11, 12, 13, etc. Adjacent cushion pieces 10 may be bonded together with a thermosetting resin, or may simply be stacked within the guide member 2. A long C / C composite material in the pressing direction PF is relatively difficult to manufacture, and problems may arise in terms of quality and cost. In contrast, a short C / C composite material is relatively easy to manufacture and has the advantages of being excellent in terms of quality and cost. The above advantages can be achieved by making the cushion member 1 a laminate of divided pieces (cushion pieces 10).

[0036] [Description of the embodiment of the processing device] Hereinafter, various processing devices to which the cushion device CA is applied will be described with reference to FIGS.

[0037] First Embodiment FIG. 3 is a cross-sectional view showing a processing apparatus PA according to a first embodiment of the present invention. For ease of explanation, FIG. 3 is indicated by X and Y directions. The processing apparatus PA is an apparatus including a compression mold for hot forming a workpiece W, and is equipped with a cushion device CA including the cushion member 1 and guide member 2 described above, an outer mold 3, a first inner mold 41 and a second inner mold 42, and a heating device (not shown). In the hot environment created by the heating device, the processing apparatus PA compresses and diffusion-bonds the workpiece W, which is a stack of multiple plate materials WP arranged in the X direction, in the X direction. The processing apparatus PA may also be one that uses 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 the 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 a plan view, with the +X side being an accommodation space for the cushion device CA and the -X side being a forming chamber RA for the workpiece W.

[0039] The cushion member 1 of the cushion device CA has a rod-like shape and is arranged in the internal space R surrounded by the guide member 2. The cushion member 1 is oriented so that the lamination direction of its fiber-containing layers is the X direction. The thermal expansion coefficient of the cushion member 1 is larger than that of the outer mold 3. It is sufficient that the thermal expansion coefficient of the cushion member 1 is larger than that of at least the portion constituting the inner surface 31 of the outer mold 3. The thermal expansion coefficient of the C / C composite material in the lamination direction is 8×10 -6 ~10×10 -6 / °C, the above requirement can be met by selecting a material that hardly undergoes thermal expansion as the constituent material of the outer mold 3.

[0040] The first inner die 41 and the second inner die 42 are made of, for example, cemented carbide, hot die steel, ceramics, or carbon-based materials and have a rectangular parallelepiped shape. The thermal expansion coefficients of these inner dies 41 and 42 are also greater than that of the outer die 3. It is sufficient that the thermal expansion coefficients of the inner dies 41 and 42 are greater than that of at least the portion of the outer die 3 that constitutes the inner surface 31. The first inner die 41, the second inner die 42, and the inner surface 31 of the outer die 3 define a molding chamber RA for the workpiece W. The first inner die 41 forms the +X side of the molding chamber RA and is adjacent to the first end face 1a on the -X side of the cushion member 1. The second end face 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 die 42 forms the -X side of the molding chamber RA and is adjacent to the -X inner surface 31B. Here, "adjacent" not only refers to a state in which the first end face 1a and the second end face 1b are always in contact with each other with a press-fit margin, but also to a state in which there is a gap between them when cold but they are in contact when hot.

[0041] The processing device PA does not have a mechanical mechanism for compressing the workpiece W, such as a hot press, but instead, the workpiece W is press-fit between the inner dies 41, 42 and cushion member 1, and diffusion-bonded based on the difference in thermal expansion coefficients between the outer die 3 and the inner dies 41, 42 and cushion member 1. When a heating device (not shown) creates a hot environment in the molding chamber RA containing the workpiece W and its surroundings, the inner dies 41, 42 thermally expand more than the outer die, and the cushion member 1 and workpiece W also thermally expand, so the workpiece W is press-fit 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 die 3 and is in a stopped state, and the first end surface 1a presses the workpiece W via the first inner die 41.

[0042] The cushion member 1 applies a compressive force (pressing force F2 in FIG. 1) to the workpiece W, while elastically absorbing a reaction force F3 from the workpiece W. With 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, which is a stack of plate materials WP, can be appropriately diffusion bonded without causing defects such as poor molding due to insufficient compressive force or breakage due to excessive compressive force.

[0043] It is desirable to incorporate the cushion member 1 between the first inner die 41 and the +X inner surface 31A in a state in which it is pre-compressed in the X direction while cold. This allows a pressing force due to the compression and recovery force of the cushion member 1 to act on the workpiece W during heating, in addition to the pressing force due to the thermal expansion of the inner dies 41 and 42. If a relatively large pressing force can be generated in the X direction based on the thermal expansion or compression and recovery force of the cushion member 1, either or both of the first inner die 41 and the second inner die 42 may be omitted. For example, a configuration may be adopted in which the first end surface 1a of the cushion member 1 directly presses the workpiece W.

[0044] 4A to 4D are cross-sectional views showing an example of a processing process for a workpiece W using the processing apparatus PA of the first embodiment. FIG. 4A shows a state in which the workpiece W is set in the processing apparatus PA in a cold state before diffusion bonding. Here, an example is shown in which the cushion member 1 is composed of two cushion pieces 10. As in the preferred example described above, the cushion member 1 is inserted between the first inner die 41 and the +X inner surface 31A in a state in which it is compressively elastically deformed 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 die 41 based on its compressive elasticity in a cold state. The -X surface of the first inner die 41 abuts against the +X end surface of the workpiece W. The +X surface of the second inner die 42 abuts against the workpiece W, and the -X surface abuts against the -X inner surface 31B. If the compression allowance can be secured by thermal expansion of the inner molds 41 and 42, the inner molds 41 and 42 may be clearance-fitted.

[0045] 4(B) shows the state in which the processing device PA is being heated, and FIG. 4(C) shows the state in which the processing device PA has reached the hot forming temperature and compressive forces F21 and F22 are acting on the workpiece W. As mentioned above, the outer mold 3 hardly undergoes thermal expansion, but the inner molds 41 and 42, cushion member 1, and workpiece W do thermally expand, as shown by the arrows in the figure. As a result, the workpiece W is compressed in the X direction. The +Y and -Y sides of the workpiece W abut against the inner surface 31 of the outer mold 3, so no disturbance occurs in the arrangement of the sheet material WP.

[0046] At this time, the cushion member 1 presses the workpiece W based on thermal expansion and compression recovery forces while elastically absorbing the reaction force from the workpiece W. Generally, the workpiece W, which is a laminate of plate materials WP, has dimensional variations in the compression direction (X direction). When the workpiece W is larger than the standard dimension, the amount of compression of the workpiece W due to thermal expansion of the inner molds 41 and 42 and the cushion member 1 during heating is greater than the standard. In other words, the compression margin of the workpiece W is large. Without the cushioning effect, excessive compression force acts on the workpiece W, which may damage the workpiece W or the outer mold 3. However, in this embodiment, the cushion member 1 absorbs the reaction force corresponding to the excessive compression force on the workpiece W. In other words, when a reaction force exceeding the standard is generated from the workpiece W, the cushion member 1 is elastically compressed by an amount equal to the excess reaction force. Therefore, the compression forces F21 and F22 acting on the workpiece W can be set to standard values, enabling proper diffusion bonding to be achieved.

[0047] Conversely, if the workpiece W is smaller than the standard dimensions, the amount of compression of the workpiece W due to thermal expansion of the inner dies 41, 42 and the cushion member 1 during heating may be less than the standard. In this case, the compressive forces F21 and F22 may be insufficient, resulting in insufficient compression of the workpiece W. However, even in such a case, in this embodiment, the reaction force absorbed by the cushion member 1 is simply less than the standard. In other words, the cushion member 1 applies a pressing force corresponding to the reaction force to the first inner die 41, thereby applying the standard values ​​of compressive forces F21 and F22 to the workpiece W. Therefore, proper diffusion bonding can be achieved. As described above, the cushion member 1 made of a C / C composite material exhibits a compressive force adjustment function that generates an appropriate compressive force in accordance with the dimensional variations of the workpiece W.

[0048] As the hot forming process shown in Figure 4(C) is performed, the workpiece W eventually softens, causing adjacent sheets WP to be pressed together. Figure 4(D) shows the state after the processing device PA has cooled after hot forming. Due to thermal contraction resulting from the pressing and cooling, the dimension of the processed workpiece W in the X direction is reduced by Δd after processing. As a result, the cushion member 1 returns to an uncompressed state or its initial lightly pressed-in state. Furthermore, the inner molds 41 and 42 and the workpiece W are in loose contact or a gap is formed between them. Therefore, the workpiece W can be easily removed from the processing device PA.

[0049] In the first embodiment described above, the thermal expansion coefficients of the cushion member 1 and the inner molds 41, 42 are larger than that of the outer mold 3. The relationship between the thermal expansion coefficients of the cushion member 1, the inner molds 41, 42, and the outer mold 3 is not limited to that of the first embodiment. Even if the thermal expansion coefficients of the cushion member 1 and the inner molds 41, 42 are set smaller than that of the outer mold 3, the workpiece W can be diffusion bonded. Two examples of diffusion bonding in such settings are shown below.

[0050] First, a case where the workpiece W is diffusion bonded with a relatively light load will be described. In this case, the cushion member 1 is lightly pressed in beforehand. Because the restraining force of the outer mold 3 on the inner molds 41, 42 during thermal expansion is weak, it is easy to make the thermal expansion amounts of the inner molds 41, 42 (the amount of expansion in the stacking direction of the workpiece W) and the outer mold 3 the same by appropriately selecting the materials of the inner molds 41, 42 and the outer mold 3. Therefore, the load acting on the workpiece W when hot is the same as the load acting on the workpiece W when cold. In other words, the load acting on the workpiece W when hot is the load generated by the light pressing, making diffusion bonding possible with a relatively light load. An example of the workpiece W is oxygen-free copper, which can be diffusion bonded with a relatively light load. In this case, the outer mold 3 used is hot die steel (thermal expansion coefficient 13×10 -6 / ℃), and the inner molds 41 and 42 are made of cemented carbide (thermal expansion coefficient 5×10 -6 When oxygen-free copper is diffusion bonded at about 400° C., a C / C composite material is suitable for the cushion member 1.

[0051] Next, we will explain the case where the cushion member 1 is diffusion-bonded after being forcefully pressed in. The degree of forceful pressing is set as large as possible, taking into account a safety factor based on the compressive yield strength of the cushion member 1. In this case, the restraining force of the outer die 3 on the inner dies 41 and 42 can be weakened by appropriately selecting the materials of the outer die 3 and the inner dies 41 and 42 so that the thermal expansion of the outer die 3 is greater than that of the inner dies 41 and 42. This allows the load of the inner dies 41 and 42 and the cushion member 1 on the workpiece W to be released in the +X and -X directions, opposite the stacking direction. Therefore, even when the cushion member 1 is forcefully pressed in, an appropriate load can be applied to the workpiece W, and damage to the workpiece W due to excessive compressive force can be prevented. An example of the workpiece W is oxygen-free copper. For example, the outer die 3 is made of hot die steel, and the inner dies 41 and 42 are made of cemented carbide. When oxygen-free copper is diffusion bonded at about 400° C., a C / C composite material is suitable for the cushion member 1 .

[0052] Furthermore, when the thermal expansion coefficients of the inner dies 41, 42 and the outer die 3 are equal, that is, when they are made of the same material, diffusion bonding of the workpiece W is possible. In this case, by appropriately setting the dimensions of the inner dies 41, 42 and the outer die 3 in the stacking direction X of the workpiece W, the amount of expansion of each of the inner dies 41, 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 differs from the first embodiment in that an overpressure prevention block 7 extending along the stacking direction of the workpiece W is disposed between the first inner die 41 and the second inner die 42. A gap G, which determines the compression margin of the workpiece W, is formed between the +X end face of the overpressure prevention block 7 facing the first inner die 41 and the -X end face of the first inner die 41 facing the +X end face of the overpressure prevention block 7. When the cushion member 1 and the inner dies 41 and 42 thermally expand and compress the workpiece W by the amount of gap G, the -X end face of the first inner die 41 abuts against the +X end face of the overpressure prevention block. This prevents the workpiece W from being compressed beyond the compression margin. As a result, damage due to excessive compression force is prevented. Note that the gap G is exaggerated in the illustration.

[0054] Furthermore, although not shown in the figures, a surface pressure distribution plate may be disposed between the first end face 1a of the cushion member 1 and the inner surface 31 of the outer mold 3, along the inner surface 31. When the cushion member 1 thermally expands and presses the inner surface 31, the surface pressure exerted by the first end face 1a on the inner surface 31 increases. However, by disposing a surface pressure distribution plate, the surface pressure exerted on the inner surface 31 can be reduced. If the thermal expansion coefficient of this surface pressure distribution plate is appropriately selected, it can also function 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 perpendicular to the stacking direction of the workpieces W, and a plurality of workpieces W may be diffusion bonded simultaneously. Alternatively, a plurality of inner dies 41, 42 and workpieces W may be arranged in the X direction, which is the stacking direction of the workpieces W, and diffusion bonding may be performed by pressing from the inner die 41 with one cushion member 1 or by pressing with two cushion members arranged on both sides of the inner dies 41, 42. Furthermore, diffusion bonding may be performed by placing a cushion member 1 between the inner dies 41 and 42 of adjacent arrays.

[0056] Second Embodiment In the first embodiment, an example is shown in which cushion members 1 are arranged only on the side surfaces in the X direction of the workpiece W. In the second embodiment, an example is shown in which cushion members are arranged on each of the three side surfaces in the X, Y, and Z directions of the workpiece W. Note that it is also possible to arrange cushion members on any two of the three side surfaces.

[0057] 6(A) is a partially cutaway side view of a processing apparatus PA1 according to the second embodiment as seen from the Z direction, and FIG. 6(B) is a side view of the processing apparatus PA as seen from 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 mold 30 corresponding to the outer mold 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 the function of applying a compressive force to the workpiece W while elastically absorbing a reaction force from 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 mold 30 has a rectangular frame shape and has +X inner surfaces 31A, -X inner surfaces 31B, +Y inner surfaces 31C, and -Y inner surfaces 31D that define an internal space R. The outer guide 5 is a rectangular frame that surrounds the outer mold 30 in the YZ directions and has an inner surface 51 that includes a -Z inner surface 51A and a +Z inner surface 51B.

[0059] The six plates 431, 432, 441, 442, 451, and 452 surrounding the workpiece W correspond to the inner molds 41 and 42 of the first embodiment and are made of materials that do not adhere to the workpiece W under hot welding. The six plates 431, 432, 441, 442, 451, and 452 are arranged to surround six sides of the workpiece W and define a forming chamber RA for the workpiece W. A first X plate 431 is adjacent to the +X side of the workpiece W, and a second X plate 432 is adjacent to the -X side. The +X side of the first X plate 431 is in contact with the -X end of the first cushion member 1A. The -X side of the second X plate 432 is in contact with the -X inner surface 31B of the outer mold 30 and also serves as a load support.

[0060] The first Y plate 441 is adjacent to the +Y side of the workpiece W, and the second Y plate 442 is adjacent to the -Y side. The -Y end of the second cushion member 1B abuts against the +Y side of the first Y plate 441. The -Y side 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 of the workpiece W, and the second Z plate 452 is adjacent to the -Z side. The -Z end of the third cushion member 1C abuts against the +Z side of the first Z plate 451. The -Z side 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 that receives the impact load of first cushion member 1A is disposed between the +X end of first cushion member 1A and +X inner surface 31A of outer mold 30. Similarly, a second load-receiving plate 47 is disposed between the +Y end of second cushion member 1B and +Y inner surface 31C of outer mold 30, and a third load-receiving plate 48 is disposed between the +Z end of third cushion member 1C and +Z inner surface 51B of outer guide 5.

[0062] The desirable relationship between the thermal expansion coefficients of the components that make up the processing device PA1 is as follows. The thermal expansion coefficients of the outer mold 30 and outer guide 5 are α1 and α2, respectively. The thermal expansion coefficients of the first cushion member 1A, second cushion member 1B, and third cushion member 1C are β1, β2, and β3, respectively. The thermal expansion coefficient of the six plates 431, 432, 441, 442, 451, and 452 that surround the workpiece W is γ, and the thermal expansion coefficient of the three load-receiving plates 46, 47, and 48 is δ. In this case, α1<β1, α1<β2, α2<β3 α1<γ, α1<δ, α2<γ, α2<δ It is desirable to satisfy the following relationship.

[0063] As long as the above-mentioned thermal expansion coefficient relationships are satisfied, the workpiece W can be hot-compressed without using a hot press or the like based on the thermal expansion difference between the outer mold 30 and the outer guide 5 and the cushion members 1A, 1B, and 1C, plates 431, 432, 441, 442, 451, and 452, and load-receiving plates 46, 47, and 48 arranged inside them. If the cushion members 1A, 1B, and 1C are assembled in a pre-compressed state, their compressive restoring force can be superimposed on the thermal expansion force to compress the workpiece W. If the compression force is insufficient, a hot press may be additionally used to assist in the compression of the workpiece W. For example, the outer guide 5, the third cushion member 1C, and the third load-receiving plate 48 can be removed, and the first Z-plate 451 can be directly pressed with the hot press.

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

[0065] Third Embodiment The third embodiment and the fourth and fifth embodiments described below exemplify processing equipment equipped with a working unit that performs press processing on a workpiece. The cushion device CA is arranged to directly or indirectly press portions of the workpiece other than the area to be press-processed. In each embodiment, the cushion device CA is arranged so that the working unit can press the workpiece while the cushion member 1 properly presses the workpiece with a pressing force corresponding to the reaction force from the workpiece. The arrangement of the cushion device CA makes it possible to perform the desired press processing on the workpiece.

[0066] FIG. 7 is a side cross-sectional view of a punching apparatus PA2, a third embodiment of the processing apparatus according to the present invention. The up, down, left, and right directions shown in FIG. 7 are for convenience of explanation and do not limit the direction of use of the punching apparatus PA2. The working unit that performs press processing in the punching apparatus PA2 is a punch 6 that can move up and down, and the workpiece is a punched plate WA. The punching apparatus PA2 is a device that can perform fine blanking processing using the hydrostatic pressure effect. When the punch 6 is lowered toward the punched plate WA, whose upper and lower surfaces are constrained, the tip 6T of the punch 6 penetrates the punched plate WA vertically, punching out a punched piece WAT. After punching, the punch 6 is raised and lowered.

[0067] The punching device PA2 is equipped with a first cushion device CA1 and a second cushion device CA2 as a pressing mechanism for pressing the punched plate WA during punching. The punching device PA2 also is equipped with a punch 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 as a punching mechanism using the punch 6.

[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 between them. The cushion devices CA1 and CA2 include a cushion member 1 and a push block 22 arranged on the lower end side of the cushion member 1. The can plate 61 is a base 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 an attachment hole for the punch 6 and holds the punch 6. The can 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 components also move up and down integrally.

[0069] The stripper plate 65 is arranged to abut against the upper surface of the punched plate WA. The stripper plate 65 has a through hole that allows the punch 6 to pass through and an annular protrusion that bites into the upper surface of the plate WA. The die plate 66 is arranged to abut against the lower surface of the plate WA and presses down on the plate WA from below. The lower backing plate 67 is arranged on the lower surface of the die plate 66. The lower bed 68 is a stationary base that supports the lower backing plate 67 and the die plate 66. A punching hole 6H is drilled so as to vertically penetrate the die plate 66, the lower backing plate 67, and the lower bed 68. The punched piece WAT is collected through the punching hole 6H.

[0070] The punched plate WA is sandwiched between the stripper plate 65 and the die plate 66, and is punched by the punch while its upper and lower surfaces are constrained. This allows a punched piece WAT to be sheared off from the punched plate WA. The push blocks 22 of the cushion devices CA1 and CA2 abut against the stripper plate 65 when the upper bed 62 descends, thereby pressing down on the plate WA. In other words, the stripper plate 65 abuts against the plate WA around the periphery of the punching area. The cushion devices CA1 and CA2 generate a pressing force F2 that presses the stripper plate 65.

[0071] The push block 22 abuts against the stripper plate 65 before the tip 6T of the punch 6 abuts against the plate WA, and applies a pressing force F2 throughout the punching and withdrawing operations of the punch 6. That is, when the push block 22 abuts against the stripper plate 65, the cushion member 1 is compressed and elastically deformed, generating the pressing force F2. The length between LV1 and LV2 shown 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, while elastically absorbing 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 in accordance with the reaction force.

[0072] The pressing force F2 of the cushion member 1 is also used as a stripping force to peel 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, it is possible that the punched piece WAT may get stuck to the tip 6T and not be peeled off. However, in this embodiment, even when the punch 6 rises, the push block 22 continues to press the stripper plate 65 for a period corresponding to the length of the compression allowance. In other words, the cushion member 1, which is compressed and elastically deformed by the reaction force from the stripper plate 65, returns to its original shape as the upper bed 62 rises, and the pressing force F2 based on this restoring force presses the stripper plate 65. This pressing force F2 serves as a stripping force to peel the punched piece WAT from the punched plate WA. Therefore, the punched piece WAT can be easily stripped from the punch 6.

[0073] <Fourth embodiment> FIG. 8 is a side cross-sectional view of a forging 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 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 presses against the upper surface (first surface) of the forging WB from the vertical direction, forging the forging WB into a desired shape. After forging, the forging punch 6A is raised.

[0074] The forging device PA3 includes a first cushion device CA1, a second cushion device CA2, a can 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, similar to the punching device PA2 of the third embodiment. The punch plate 64 holds the forging punch 6A. 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 is opened in the lower bed 68A and extends in the vertical direction, and a cushion member 1 that is accommodated in the guide hole 68H. The cushion member 1 supports the pushback pin 60 from below and functions as a die cushion.

[0075] A presser plate 69 having a through-hole for the forging punch 6A is disposed between the punch plate 64 and the die plate 66. The presser plate 69 presses down on the forging WB during forging and contacts the upper surface of the forging WB around the forging area. As the upper bed 62 descends, the push blocks 22 of the pair of left and right cushion devices CA1 and CA2 press against the presser plate 69, applying a pressing force F2. Meanwhile, a pushback force F4 generated by the third cushion device CA3 is applied to the underside of the forging WB via the pushback pin 60.

[0076] The push block 22 of the cushion devices CA1 and CA2 abuts against the presser plate 69 before the tip 6AT of the forging punch 6A contacts the forging WB, and applies a pressing force F2 during the forging of the forging WB by the forging punch 6A and during the withdrawal operation after shaping. That is, when the push block 22 abuts against the presser plate 69, the cushion member 1 undergoes compressive elastic deformation, generating the pressing force F2. While applying the pressing force F2 to the presser plate 69, the cushion member 1 elastically absorbs the reaction force from the presser plate 69. That is, the cushion member 1 can apply an appropriate pressing force F2 to the presser plate 69 in accordance with the reaction force. This allows for highly accurate forging.

[0077] When the forging WB is pressed downward by the forging punch 6A, a portion of the forging WB enters the relief hole in the die plate 66. This forces the pushback pin 60, which is in contact with the underside of the forging WB, downward, compressing the cushion member 1 of the third cushion device CA3. The cushion member 1 elastically absorbs the reaction force from the pushback pin 60 and generates a pushback force F4 that pushes the pushback pin 60 upward. Furthermore, even after the forging punch 6A separates from the forging WB and rises, the pushback force F4 continues to act on the pushback pin 60 due to the restoring force of the cushion member 1, which is elastically compressed and deformed by the reaction force. This restoring force can be used as a knockout force that pushes the forging WB out of the die plate 66 after forging. This improves the ease of removal of the forging WB after forging.

[0078] Fifth Embodiment 9 is a side cross-sectional view of a forging apparatus PA4, which is a fifth embodiment of the processing apparatus according to the present invention. The working part that performs press working in the forging 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 presses vertically against the upper surface of the forging WC, forging the forging WC into the required shape. After forging, the forging punch 6B is raised.

[0079] The forging device 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 cushioning mechanism, the forging device PA4 includes a cushioning device CA similar to that shown in FIG. 1 (illustration is simplified in FIG. 9). As the upper bed 62 descends, the forging punch 6B forges and shapes the forging WC placed on the die plate 66. FIG. 9 shows an example in which the tip 6BT of the forging punch 6B presses down near the right end of the forging WC.

[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. In other words, the cushion device CA presses the forging WC with an appropriate pressing force F2 according to the reaction force. This prevents processing defects caused by excessive or insufficient pressing load on the forging WC. [Explanation of symbols]

[0081] 1 Cushion member 1a, 1b 1st end face, 2nd end face 2 Guide member 3, 30 external mold 41 First inner mold 42 Second inner mold 5 Outer guide 6 Punch (working part) 6A Forging punch (working part / forging die) 65 Stripper plate (plate that contacts the workpiece) 69 Presser plate (plate that contacts the workpiece) CA cushion device CA1, CA2, CA3 1st, 2nd, 3rd cushion devices PA processing equipment PA1 punching processing device (processing device) PA2, PA3, PA4 Forging forming processing equipment (processing equipment) R Interior space RA molding room W Work material WA punched plate (workpiece) WB, WC Forgings (work material)

Claims

1. a cushion member that elastically absorbs a reaction force from the workpiece that occurs as the workpiece is formed, and presses the workpiece in a direction opposite to the direction in which the reaction force acts; The cushion device, wherein the cushion member is made of a carbon matrix composite material.

2. The cushion device according to claim 1, The cushion device, wherein the carbon matrix composite is a carbon fiber reinforced carbon composite.

3. an outer mold including an inner surface defining an interior space including a molding chamber in which the workpiece is molded; and the cushion device according to claim 1, which is disposed in the internal space. The cushion member is a first end surface capable of pressing the 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 the workpiece and the second end surface abuts against the inner surface of the outer mold.

4. The processing device according to claim 3, The cushion member has a thermal expansion coefficient greater than that of at least a portion of the outer mold that constitutes the inner surface of the outer mold.

5. 5. The processing apparatus according to claim 3 or 4, 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, The inner mold has a thermal expansion coefficient set so as to press the workpiece in the hot environment.

6. The processing apparatus according to claim 5, The inner mold has a thermal expansion coefficient greater than that of at least a portion of the outer mold that constitutes the inner surface.

7. 5. The processing apparatus according to claim 3 or 4, 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.

8. The processing device according to claim 7, The processing device, 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.

9. a working section that applies press processing to the workpiece; A processing apparatus comprising: the cushion device according to claim 1, which is arranged to directly or indirectly press a portion of the workpiece other than the area to be press-processed.

10. 10. The processing apparatus according to claim 9, the working unit is a punching die that performs punching on a workpiece, The cushion device is arranged to press a plate that contacts the workpiece around the punching area.

11. The processing apparatus according to claim 10, the working unit is a forging die for forging a workpiece, The cushion device is arranged to press a plate that contacts the workpiece around the forging area.

12. The processing apparatus according to claim 11, the workpiece includes a first surface to be subjected to the press working and a second surface opposite to the first surface, The cushion device is arranged to press against the second surface.

Images