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(11) | EP 2 306 025 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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DIE FOR FORGING ROTOR MATERIAL AND METHOD FOR FORGING ROTOR MATERIAL GESENK ZUM SCHMIEDEN VON ROTORMATERIAL UND VERFAHREN ZUM SCHMIEDEN VON ROTORMATERIAL EMPREINTE ET PROCÉDÉ DE FORGEAGE D UN MATÉRIAU POUR ROTOR |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
TECHNICAL FIELD
[0001] The present invention relates to a rotor material forging die assembly for producing a rotor material having vane grooves at its outer peripheral portion, and a method for forging the rotor material. In particular, the invention relates to a die assembly according claim 1 and a method according to claim 10.
BACKGROUND ART
[0002] A die assembly and a method of the initially-mentioned type are known from, e.g. US 6,094,815 A; JP10296382 A discloses a further die assembly.
[0003] A rotor for a compressor or a rotor for a rotary type vacuum pump for use in a brake controller is generally provided with a plurality of vane grooves parallel to an axial center formed in an outer peripheral portion at equal intervals in the circumferential direction. Further, most of rotors for an air-conditioning rotary compressor and for a rotary vacuum pump for used in a brake controller, which are to be mounted on a vehicle, are aluminum alloy products for the purpose of attaining the weight saving, and generally produced by forge processing.
[0004] For example, according to the rotor production method disclosed by the following Patent Document 1, using a lower die having a forming hole in which vane portions for forming vane grooves are formed, a cylindrical columnar forging raw material set on the forming hole is downwardly pressed with an upper die to thereby fill the forging raw material in the forming hole. With this, a cylindrical columnar rotor material in which each vane groove extends from the lower end face near to the upper end face is formed can be obtained. The upper end portion (excess thickness portion) of the rotor material is removed by cutting along a plane perpendicular to the axial line to open one end side (upper end side) of each vane groove, resulting in vane grooves with both ends thereof opened. Thus, a rotor material is formed.
[0005] Further, according to the rotor production method disclosed by the following Patent Document 2, using an upper die provided with groove forming punches for forming vane grooves at the forming surface of the upper die, the upper die with the groove forming punches are driven into a forging raw material set in the forming hole of the lower die, to thereby form vane grooves extending from the upper end face near to the lower end face. Subsequently thereafter, a groove forming punch is driven therein to punch out and remove the excess thickness portion closing the lower end side of the vane groove to open both ends of the vane groove.
PRIOR ART DOCUMENT
PATENT DOCUMENT
[0006]
Patent Document 1: Japanese Unexamined Laid-open Patent Publication No. Hll-230068 (JP H11-230068, A)
Patent Document 2: Japanese Unexamined Laid-open Patent Publication No. 2000-220588 (JP 2000-220588, A)
SUMMARY OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0007] In the conventional rotor producing method disclosed by the aforementioned Patent Document 1, the excess thickness portions of the rotor material obtained by forge processing are removed. It is, however, difficult to perform the removal operation of the excess thickness portions, which may cause deterioration of the production efficiency.
[0008] Further, in the conventional rotor production method disclosed by the aforementioned Patent Document 2, the excess thickness portion blocking the lower end portion of the vane groove is punched out and removed with a groove forming punch. It is, however, difficult to accurately control the breaking position, and therefore has a high probability of causing unexpected breaks or lacks. Accordingly, there is a problem that the excess thickness portion cannot be removed accurately.
[0009] The preferred embodiments of the present invention have been developed in view of the above-mentioned and/or other problems in the related art. The preferred embodiments of the present invention can significantly improve upon existing methods and/or apparatuses.
[0010] The present invention was made in view of the aforementioned problems, and aims to provide a die assembly for forging a rotor material and a method for forging a rotor material capable of accurately removing an excess thickness portion while securing high production efficiency.
[0011] Other objects and advantages of the present invention will be apparent from the following preferred embodiments.
MEANS FOR SOLVING THE PROBLEMS
[0012] In order to attain the aforementioned objects, the present invention is provided with the following structures.
Item 1: A die assembly defined in claim 1.
Item 2: The die assembly for forming the rotor material as recited in the aforementioned Item 1, wherein when a distance between the upper end face of the vane portion and the lower end face of the vane portion corresponding hole at the time of die matching is defined as a vane groove side end face distance, the vane groove side end face distance is set to 0 to 2 mm.
Item 3: The die assembly for forming the rotor material as recited in the aforementioned Item 1 or 2, wherein when a distance between an outer periphery of the vane portion and an inner periphery of the vane portion corresponding hole is defined as a vane groove side clearance, the vane groove side clearance is set to 0.01 to 0.1 mm.
Item 4: The die assembly for forming the rotor material as recited in the aforementioned Item 3, wherein, among the vane groove side clearance, at least one of an inner peripheral side end portion clearance and an outer peripheral side end portion clearance is set to be larger than an intermediate portion clearance.
Item 5: The die assembly for forming the rotor material as recited in any one of the aforementioned Items 1 to 4, wherein an upper end face of the center pin is arranged so as to coincide with or distance from a lower end face of the center pin corresponding hole at the time of die matching.
Item 6: The die assembly for forming the rotor material as recited in the aforementioned Item 5, wherein when a distance between the upper end face of the center pin and the lower end face of the center pin corresponding hole at the time of die matching is defined as a center hole side end face distance, the center hole side end face distance is set to 0 to 2 mm.
Item 7: The die assembly for forming the rotor material as recited in the aforementioned Item 5 or 6, wherein when a distance between an outer periphery of the center pin and an inner periphery of the center pin corresponding hole is defined as a center hole side clearance, the center hole side clearance is set to 0.01 to 0.1 mm.
Item 8: The die assembly for forming the rotor material as recited in any one of the aforementioned Items 1 to 7, further comprising a sub-load applying means provided above the back-pressure pin so as to apply a first sub-load to the back-pressure pin, and a sub-load applying means provided above the back-pressure plate so as to apply a second sub-load to the back-pressure plate.
Item 9: The die assembly for forming the rotor material as recited in the aforementioned Item 8, wherein the sub-load applying means is a gas cushion.
Item 10: A method of forging a generally cylindrical columnar rotor material having a center hole and a vane groove extended parallel to an axial line and formed in an outer peripheral portion, comprising the features of claim 10.
Item 11: The method of forging the rotor material as recited in the aforementioned Item 10, wherein an upper end face of the center pin is arranged so as to coincide with or distance from a lower end face of the center pin corresponding hole at the time of die matching.
Item 12: The method of forging the rotor material as recited in the aforementioned Item 10 or 11, wherein the first sub-load and the second sub-load are set to 29 to 89 MPa, respectively.
Item 13: The method of forging the rotor material as recited in any one of the aforementioned Items 10 to 12, wherein the first sub-load is decreased as a cross-sectional area of the center pin increases.
Item 14: The method of forging the rotor material as recited in any one of the aforementioned Items 10 to 13, wherein the rotor material is made of aluminum or an aluminum alloy.
EFFECTS OF THE INVENTION
[0013] According to the die assembly for forging a rotor material of the item 1, since a rotor material in which one end face of the vane groove is positioned inner than the end face of the rotor portion can be obtained, the radius difference between the inner periphery of the vane groove and the outer periphery of the excess thickness portion can be reduced. For this reason, the vane groove side excess thickness portion can be removed easily and appropriately, and therefore the productivity can be improved.
[0014] According to the die assembly for forging a rotor material of the item 2 and 3, the aforementioned effects can be obtained assuredly.
[0015] According to the die assembly for forging a rotor material of the item 4, it is possible to prevent improper dropping of the excess thickness portion.
[0016] According to the die assembly for forging a rotor material of the item 5, since a rotor material processed article in which one end face of the center hole is positioned inner than the end face of the rotor portion can be obtained, the radius difference between the inner periphery of the center hole and the outer periphery of the excess thickness portion can be reduced. For this reason, the center hole side excess thickness portion can be removed easily and appropriately, and therefore the productivity can be improved.
[0017] According to the die assembly for forging a rotor material of the item 6 and 7, the aforementioned effects can be obtained more assuredly.
[0018] According to the die assembly for forging a rotor material of the item 8 and 9, the flexural deformation and/or torsional deformation of the center pin and the vane portion can be restrained.
[0019] According to the method of forging a rotor material of the item 10, in the same manner as mentioned above, the same functions and effects can be obtained.
[0020] According to the method of forging a rotor material of the item 11 and 12, the aforementioned effects can be obtained more assuredly.
[0021] According to the method of forging a rotor material of the item 10, the first sub-load and the second sub-load can be set independently in accordance with the shape and dimension of the center pin and the vane portion, which can more assuredly maintain the balance between the metal flow toward the outer periphery and a force for causing an inward deformation of the vane portion at the time of forming the center hole.
[0022] According to the method of forging a rotor material of the item 13, the aforementioned effects can be obtained more assuredly.
[0023] According to the method of forging a rotor material of the item 14, an aluminum or aluminum alloy rotor material excellent in dimensional accuracy can be forged with a high material yield.
BRIEF DESCRIPTION OF DRAWINGS
[0024]
[Fig.1] Fig. 1 is an exploded perspective view showing a rotor material forging die assembly according to an embodiment of the present invention.
[Fig. 2A] Fig. 2A is a schematic cross-sectional view showing the forge processing at the stage of preparing the forge processing using the forging die assembly according to the embodiment.
[Fig. 2B] Fig. 2B is a schematic cross-sectional view showing the forge processing at the stage of descending the upper die using the forging die assembly according to the embodiment.
[Fig. 2C] Fig. 2C is a schematic cross-sectional view showing the forge processing at the processing completion stage using the forging die assembly according to the embodiment.
[Fig. 2D] Fig. 2D is a schematic cross-sectional view showing the forge processing at the stage of taking out the processed member using the forging die assembly according to the embodiment.
[Fig. 3] Fig. 3 a perspective view showing a rotor material obtained by the forge processing according to the embodiment.
[Fig. 4] Fig. 4 is a perspective view showing a rotor to be produced by the production method of the embodiment.
[Fig. 5] Fig. 5 is a plan view showing the offset amount of the vane groove of the rotor material.
[Fig. 6] Fig. 6 is a perspective view showing the assembled state of the upper die of the forging die assembly of the embodiment.
[Fig. 7A] Fig. 7A is a partially cut-out perspective view showing the load applying state to the lower die of the forging die assembly.
[Fig. 7B] Fig. 7B is an explanatory view for explaining the metal flow in the forming die assembly during the forge processing.
[Fig. 8A] Fig. 8A is a plan view of the rotor material according to the embodiment.
[Fig. 8B] Fig. 8B is an enlarged plan view showing the vane groove portion of the rotor material according to the embodiment.
[Fig. 9] Fig. 9 is a flowchart showing the step sequence of the production method in the embodiment.
[Fig. 10] Fig. 10 is across-sectional viewshowing a rotormaterial cut along the center hole according to the embodiment.
[Fig. 11] Fig. 11 is a cross-sectional view showing a rotor material cut along the vane groove according to the embodiment.
[Fig. 12] Fig. 12 is an enlarged cross-sectional view showing the portion surrounded by the alternate long and two short dashes line shown in Fig. 10.
[Fig. 13A] Fig. 13A is an enlarged cross-sectional view showing the portion surrounded by the alternate long and two short dashes line shown in Fig. 11.
[Fig. 13B] Fig. 13B is an enlarged cross-sectional view showing the vicinity of the vane groove portion of the rotor material from which the excess thickness portion was removed according to the embodiment.
[Fig. 14] Fig. 14 is a schematic cross-sectional view of a punching device used at the excess thickness portion removing step in the production method according to the embodiment.
EMBODIMENTS FOR CARRYING OUT THE INVENTION
<ROTOR>
[0025] Initially, the structure of a rotor R according to an embodiment of the present invention will be explained. As shown in Fig. 4, the rotor R is a generally cylindrical columnar member in which a center hole 3 as a shaft hole for inserting a shaft therein is formed at the center thereof and five vane grooves 4 with a groove bottom enlarged into a round in cross-section are formed in the outer peripheral surface. These vane grooves 4 are arranged in parallel with the axial line of the cylindrical columnar member and communicated with both end surfaces thereof, and also formed so as to inwardly cut into the columnar member eccentrically with respect to the center hole 3. Furthermore, as shown in Fig. 5, the offset amount U of the vane groove 4 is represented by the distance between the center line L1 extending in the groove width direction and the linear line L2 extending in parallel with the center line L1 and passing through the axial line of the rotor R.
[0026] As the material of the rotor R, aluminum or aluminum alloy is generally used. As one example, aluminum alloy consisting of Si: 14 to 16 mass%, Cu: 4 to 5 mass%, Mg: 0.45 to 0.65 mass%, Fe: 0.5 mass% or less, Mn: 0.1 mass% or less, Ti: 0.2 mass% or less, and the balance being Al and inevitable impurities can be exemplified.
<PRODUCTION STEPS>
[0027] As shown in Fig. 9, the production steps of the rotor typically include a cutting step, a mass selection step, a forging step, a punching step, a heat treatment step, and an inspection step. After these steps, a rotor product is shipped.
[0028] The cutting step and the mass selection step are steps for obtaining a forging raw material. In the cutting step, a continuously cast member is cut into a given length. After obtaining continuously cast members each having a predetermined length, the cast members are selected in accordance with the mass (weight) to obtain a desired forging raw material.
[0029] In the subsequent forging step, the forging rawmaterial is subjected to forge processing to obtain a rotor material. Thereafter, in the punching step, the excess thickness portions are removed form the rotor material to obtain a rotor R.
[0030] Thereafter, in the heat treatment step, the rotor R is subj ected to a heat treatment and a quenching treatment to improve the hardness and the abrasion resistance to thereby obtain a rotor product. Then, in the inspection step, the rotor product is subjected to a final inspection and then shipped when no defect is found.
[0031] Hereinafter, the rotor production method according to the embodiment will be explained in detail.
<FORGING STEP>
[0032] Fig. 1 and Figs. 2A to 2D show a forging die assembly as a forging device for use in forge processing, and Fig. 3 shows a rotor material 1 to be forged by the forging die assembly.
[0033] As shown in these figures, the forging die assembly includes a lower die 10 as a die and an upper die 30 as a punch for giving forming loads. As the material for these dies, well-known die steel is used.
[0034] The lower die 10 is divided into a lower die body 11 having a forming hole 12, a base 15 to be disposed at the lower side of the lower die body 11, and a bush 19 to be disposed at the upper side of the lower die body 11.
[0035] Within the forming hole 12 of the lower die body 11, a total of five vane portions 13 for forming vane grooves 4 are protruded. The vane portion 13 is a thin plate-shaped member having one end circular in cross-section and has a cross-sectional shape corresponding to that of the vane groove 4. The base 15 is formed into a plate-shape and has a center pin 16 for forming a center hole 3 of the rotor fixed at the center of the base and through-holes 18 for knockout pins 17 surrounding the center pin 16. The bush 19 is an annular plate member provided with a loading hole 20 penetrated in the up-and-down direction and having the same diameter as that of the forming hole 12 of the lower die body 11.
[0036] By assembling the base 15, the lower die body 11, and the bush 19, the center pin 16 is inserted into the forming hole 12 of the lower die body 11, forming the inner portion of the forming hole 12 into an inversion cross-sectional shape of the rotor R. Further, in this state, the loading hole 20 of the bush 19 communicates with the forming hole 12. Further, in the forging preparation step shown in Fig. 2A, the knockout pins 17 are inserted into the through-holes 18 of the base 15, and the tip end faces thereof are being held at the same height as the upper surface of the base 15.
[0037] The upper die 30 is divided into an upper die body 31 for applying a main load F to the forging rawmaterial W, a cylindrical pin 40 for applying sub-loads F1 and F2, and a flat plate 41.
[0038] In this embodiment, the cylindrical pin 40 constitutes a back-pressure pin, and the flat plate 41 constitutes a back-pressure plate.
[0039] In the upper die body 31, the lower-half punch portion 32 is formed into a generally cylindrical columnar member having an outer diameter corresponding to the through-hole 20 of the bush 19, and the larger-diameter upper half portion 33 is provided with a concave portion 34 at the upper surface thereof. Formed in this concave portion 34 is a single circular hole 35 having a cross-sect ion corresponding to the cross-section of the cylindrical pin 40 and configured to insert the cylindrical pin 40 in an advanceable and retractablemanner and five flat holes 36 each having a cross-section corresponding to the cross-section of the flat plate 41 and configured to insert the flat plate 41 in an advanceable and retractable manner. The circular hole 35 and the flat holes 36 are penetrated up to the tip end face of the punch portion 32, respectively, and the flat holes 36 are opened to the outer peripheral surface of the punch portion 32. The position of the circular hole 35 and the positions of the flat holes 35 correspond to the position of the center pin 16 and the positions of the vane portions 13 of the lower die body 11, respectively.
[0040] In this embodiment, the circular hole 36 constitutes a center pin corresponding hole, and each flat hole 35 constitutes a vane portion corresponding hole.
[0041] The cylindrical pin 40 is a cylindrical pin having a diameter larger than that of the center pin 16 in the lower die body 11, and is integrally provided with, at its upper end, a retaining portion 42 having a diameter larger than that of the circular hole 35. The flat plate 41 is a thin-plate member having a round portion at its tip end in the same manner as in the vane portion 13 of the lower die body 11, but the flat plate 41 is one size larger than the vane portion 13 and integrally provided with, at its upper end, a retaining portion 43 enlarged in cross-sectional area than the flat hole 36.
[0042] As shown in Figs. 2A and 6, in a state in which the cylindrical pin 40 is fitted into the circular hole 35 from the concave portion 34 of the upper die body 31, and the flat plates 41 are fitted into the respective flat holes 36, the upper die body 31, the cylindrical pin 40, and the flat plates 41 form a single cylindrical columnar member having a continuous tip end face and a continuous peripheral surface.
[0043] Above each of the cylindrical pin 40 and flat plates 41, a gas cushion 45 for applying a load thereto is arranged. In the gas cushion 45, a piston rod 47 is inserted into the cylinder 46 in an advanceable and retractable manner. When a force in the retracting direction is applied to the piston rod 47, the sealed compressed gas causes a force in the advancing direction equal to the force in the retracting direction. As the retraction distance increases, the force in the advancing direction increases. In each gas cushion 45, the cylinder 46 is fixed to the mounting board 48. The upper die body 31 and the mounting board 48 are assembled in a state in which the tip end of the piston rod 47 is in contact with the corresponding retaining portion 42 and 43 of the cylinder pin 40 and the flat plate 41 and an initial load by the advancing force of each piston rod 47 is applied to the corresponding cylindrical pin 40 and the flat plate 41. When the cylindrical pin 40 and the flat plates 41 are moved upward to cause retraction movements of the piston rods thereof, a load corresponding to the retracted distance is applied to each of the cylindrical pin 40 and the flat plates 41. Therefore, the mounting board 48 is configured to move up and down together with the upper die 30, but the sub-loads F1 and F2 applied to the cylindrical pin 40 and the flat plate 41, respectively, are controlled by the gas cushions 45 independent from the main load F.
[0044] The value of the first sub-load F1 and that of the second sub-load F2 can be adjusted by setting the operating load of the gas cushion 45. Furthermore, the cylindrical pin 40 and the flat plates 41 are each provided with the gas cushion 45, and therefore can be controlled in load independently. In other words, the main load F applied to the upper die body 32, the first sub-load F1 applied to the cylindrical pin 40 and the five second sub-loads F2 applied to the five flat plates 41 can be set independently.
[0045] The lower die body 10 and the upper die body 30 are arranged such that the cylindrical pin 40 and the flat plates 41 are arranged at the respective positions corresponding to the center pin 16 and the vane portions 13. Therefore, as shown in Fig. 7, the first sub-load F1 is applied to directly above the center pin 16, and the second sub-load F2 is applied to directly above the vane portion 13. The main load F is applied to the portions other than the center pin 16 and the vane portions 13. Furthermore, in this invention, each of the first sub-load F1 and the second sub-load F2 is set to a value smaller than the main load F.
[0046] Next, a method of forging a forging raw material W for producing a rotor material 1 shown in Fig. 4 will be explained with reference to Figs. 2A-2D, Fig. 7, and Fig. 8.
[0047] As shown in Fig. 2A, lubricant agent is applied to required portions of the lower die 10 and the upper die 30, and a cylindrical forging material 49 is loaded in the loading hole 20 of the bush 19. The forging raw material W is a material produced by a method, such as, e.g., a method in which a continuous cast material is cut into a predetermined length, and heated to a predetermined temperature as needed. As the aforementioned lubricant agent, aqueous graphite lubricant agent and oil-graphite lubricant agent can be exemplified. In order to prevent occurring of galling between the forging raw material W and the dies 10 and 30, it is preferable to use both the aqueous graphite lubricant agent and the oil-graphite lubricant agent. The application quantity thereof is about 2 to 10 g, respectively. Further, in cases where the forging raw material W is made of aluminum alloy, the pre-heating temperature is preferably set to 400 to 450 °C.
[0048] From this state, as shown in Fig. 2B, when the upper die 30 is moved downward with a main load F to forge the forging raw material W loaded in the lower die 10, the cylindrical pin 40 to which a first sub-load F1 smaller than the main load F is applied and the flat plates 41 to which a second sub-load F2 is applied are pushed up during the process during which the forging raw material W is being filled in the forming hole 12 to cause material inflow into the circular hole 35 and the flat holes 36. As the cylindrical pin 40 and flat plates 41 move upward in accordance with the downward movement of the upper die 30 and therefore the retreat distance of the piston rod 47 increases, the first sub-load F1 applied to the cylindrical pin 40 and the second sub-load F2 applied to the flat plate 41 increase. Thus, the main load F is applied to the portions of the forging raw material W not corresponding to the cylindrical pin 40 and the flat plates 41, while the first sub-load F1 and the second sub-load F2 independent from the main load F are applied to the portions of the forging raw material W corresponding to the cylindrical pin 40 and the flat plates 41.
[0049] As shown in Fig. 2B, applying the first sub-load F1 and the second sub-load F2, which are smaller than the main load F, to the cylindrical pin 40 and the flat plates 41 causes upward movements of the cylindrical pin 40 and the flat plates 41, resulting in material inflow into the circular hole 35 and the flat holes 36. The material inflow into the circular hole 35 and flat holes 36 reduces the forces applied to the center pin 16 and the vane portions 13. As a result, as shown in Fig. 7B, the metal flow α1 between the wall surface of the forming hole 12 and the vane portion 13 and the force α2 which causes an inward deformation of the vane portion 13 by the metal flow α1 are reduced, and further the metal flow α3 directed to the outer periphery at the time of forming the center hole 3 acts on in the direction opposite to the force α2 which causes an inward deformation of the vane portion 13. Therefore, these forces α2 and α3 are balanced, which restrains the flexural deformation and torsional deformation of the center pin 16 and the vane portions 13.
[0050] The optimum value of the first sub-load F1 and that of the second sub-load F2 are appropriately set depending on the volume of the center pin 16 and that of the vane portion 13. As these volumes increase, the escape amount of material increases. Therefore, provided that the volume of the vane portion 13 is constant, the balance can be maintained by increasing the inflow amount into the circular hole 35 by decreasing the first sub-load F1 as the volume of the center pin 16 increases.
[0051] Through the aforementioned steps, as shown in Fig. 2C, when the upper die 30 goes down to the bottom dead point, the material is formed into the shape of the rotor material 1.
[0052] In this embodiment, in a state in which the upper die 30 has reached the bottom dead point (in the die mated state), it is configured such that the level of the tip end face (upper end face) of the center pin 16 coincides with or distances from the level of the opening face (lower end face) of the circular hole 35.
[0053] Specifically, when the distance between the tip end face of the center pin 16 and the opening face of the circular hole 35 is defined as a center hole side end face difference D3, the center hole side end face difference D3 is set to 0 to 2 mm (See Fig. 12).
[0054] Furthermore, in the die mated state, it is configured such that the level of the tip end face (upper end face) of the vane portion 13 coincides with or distances from the level of the opening face (lower end position) of the flat hole 36.
[0055] Specifically, when the distance between the tip end face of the vane portion 13 and the opening face of the flat hole 36 is defined as a vane groove side end face difference D4, the vane groove side end face difference D4 is set to 0 to 2 mm (See Fig. 13A).
[0056] Furthermore, in this embodiment, when the distance between the outer periphery of the center pin 16 and the inner periphery of the circular hole 35 is defined as a center hole side clearance D5, the center hole side clearance D5 is set to 0.01 to 0.1 mm, more preferably 0.05 to 0.1 mm (see Fig. 12).
[0057] Furthermore, when the distance between the outer periphery of the vane portion 13 and the inner periphery of the flat hole 36 is defined as a vane side clearance D6, the vane side clearance D6 is set to 0.01 to 0.1 mm, more preferably 0.05 to 0.1 mm (see Fig. 13A).
[0058] Needless to say, in the case of adjusting the clearance D5 and D6, the adjustment is normally made by changing the inner diameter of the circular hole 35 and that of the flat hole 36.
[0059] After completion of driving the upper die 30, as shown in Fig. 2D, the upper die 30 is raised and the knockout pins 17 are raised to push up the forged rotor material 1. When the cylindrical pin 40 and the flat plates 41 are detached from the rotor member 1 and the forces from below are removed, the piston rods 47 of the gas cushions 45 return to the respective original positions.
[0060] In the aforementioned steps, the flexural deformation and torsional deformation of the center pin 16 and vane portions 13 of the lower die 10 are reduced, and therefore the rotor material 1 shown in Fig. 3 becomes high in dimensional accuracy of the center hole 3 and that of the vane groove 4 and the die life will be extended due to the reduced deformation. Furthermore, it is not required to enlarge the outer diameter of the rotor material to prevent deformation of the vane portion 13, and therefore no portion is required to be removed by post-processing, which incurs no waste.
[0061] Furthermore, since the first sub-load F1 and the second sub-road F2 are set to be smaller than the main load F, the materials pushed back by the cylindrical pin 40 and the vane portions 13 easily flow. This enables the upper die 30 to move downward to the height where the cylindrical pin 40 and the vane portions 13 break into the circular hole 35 and the flat holes 36, respectively. Thus, by the movements of the materials of the center hole 3 and the vane grooves 4, in the rotor material 1 to be produced, excess thickness portions 5 and 6 corresponding to the portions of the center hole 3 and the vane grooves 4 are formed on the upper end face (one end face 2a) of the rotor portion 2.
[0062] Furthermore, the first sub-load F1 and the second sub-load F2 are applied separately. Therefore, the excess thickness portion 5 above the center hole 3 and the excess thickness portion 6 above the vane groove 4 are formed separately. The respective planner shapes of the excess thickness portions become corresponding cross-sectional shapes of the cylindrical pin 40 and the flat plates 41.
[0063] In this embodiment, the back-pressures by the first and second sub-loads F1 and F2 are applied at the time of the forge processing, which can assuredly prevent such drawbacks that the excess thickness portions 5 and 6 are unintentionally ripped apart or torn off from the rotor portion 2. Thus, the excess thickness portions 5 and 6 structured as mentioned below can be integrally formed with the rotor material 1.
[0064] In this embodiment, the rotor material 1 is constituted by the rotor portion 2 and the excess thickness portions 5 and 6, and the rotor portion 2 does not include the excess thickness portions 5 and 6.
[0065] The formed excess thickness portions 5 and 6 are, as shown in Figs. 10 and 11, provided so that they protrude from one end face 2a of the rotor portion 2 toward the one end side.
[0066] Furthermore, as mentioned above, in the diemated state, each tip end face of the center pin 16 and the vane portions 13 coincides with or distances from each opening face of the circular hole 35 and the flat hole 36. Therefore, the one end faces 3a and 4a of the center hole 3 and the vane groove 4 of the rotor material 1 have not reached the inside of the excess thickness portion 5 and 6, and each one end face 3a and 4a is located inner than the one end face 2a of the rotor portion 2.
[0067] Needless to say, at the other end face (lower end face 2b) of the rotor portion 2 of the rotor material 1, the center hole 3 and the vane grooves 4 are opened.
[0068] As mentioned above, the center hole side end face difference D3 and the vane groove side end face difference D4 are set to 0 to 2 mm, respectively, and therefore each end face difference (breaking length D3, D4) between one end face 2a of the rotor portion 2 of the rotor material 1 and one end face 3a and 4a of the center hole 3 and the vane groove 4 is also set to the same value.
[0069] Furthermore, the center hole side clearance D5 and the vane groove side clearance D6 are set to 0.01 to 0.1 mm, preferably 0. 05 to 0.1 mm, respectively, and therefore the radius difference D5 andD6 between the outer periphery of the excess thickness portion 5 and 6 of the rotor material 1 and the inner periphery of the center hole 3 and the vane groove 4 is also set to the same value.
[0070] On the other hand, as shown in Fig. 8B, in this embodiment, among the radius differences between the excess thickness portion 6 and the vane groove 4, the radius difference D61 at the rotor portion outer peripheral side end portion and the radius difference D62 at the rotor portion inner peripheral side end portion are formed to be thicker than the radius difference D60 at the intermediate main portion.
[0071] Furthermore, in this embodiment, the curvature radius r3 between the inner periphery of the center hole 3 of the rotor material 1 and one end face 2a of the center hole 3 is set to 0.2 to 1 mm. Further, it is preferable that the curvature radius r4 between the inner periphery of the vane groove 4 and one end face 4a thereof is also set to 0.2 to 1 mm. By setting them within the aforementioned ranges, as shown in Fig. 13B, at the time of removing the excess thickness portion 5 and 6 by punching, it is possible to adjust the average value of the height B1 of the inner burr remained at the inner side of the center hole 3 and the vane groove 4 from the inner periphery of the center hole 3 and the vane groove 4 to a preferred value. Concretely, the height B1 of the inner burr can be set to 1 mm or less. In cases where the height B1 of the inner burr exceeds 1 mm, the breaking position becomes unstable, resulting in difficult accuracy control of the inner side dimension of the center hole 3 and that of the vane groove 4.
[0072] Furthermore, in this embodiment, it is preferable that the curvature radius r3a (r4a) between the excess thickness portion 5 (6) of the rotor material 1 and one end fade 2a of the rotor material 1 is set to be equal to or less than the inner periphery side curvature radius r3 (r4) of the excess thickness portion 5 (6). Concretely, it is preferable to satisfy the relation of "r3a ≦ r3" and "r4a ≦ r4." By setting them within the aforementioned ranges, at the time of removing the excess thickness portions 5 and 6 by punching, it is possible to adjust the average value of the protruded burr height B2 remained at one end face 2a to a preferred value. Concretely, the protruded burr height B2 can be set to 1 mm or less. Further, Lhe breaking position can also be stabilized, resulting in smaller variation of the protruded burr height B2, which makes it easy to control the cut portion control at the post-processing and therefore makes it easy to control the dimensional accuracy of the center hole 3 and the vane groove 4. In cases where the height B2 of the inner burr exceeds 1 mm, the breaking position becomes unstable, resulting in difficult accuracy control of the inner side dimension of the center hole 3 and that of the vane groove 4.
[0073] The die used in the present invention is a die for forming a rotor material having the aforementioned shape in which the curvature radius r3a is formed at the circular hole 35 of the upper die, an inversion shape of the curvature radius r4a is formed at the flat hole 36, an inversion shape of the curvature radius r3 is formed at the center pin 16 of the lower die, and an inversion shape of the curvature radius r4 is formed at the vane portion 13 .
[0074] In the forge processing of this embodiment, the main load F, the first sub-load F1, and the second sub-load F2 are appropriately set depending on the shape, the dimension of each portion, the material composition, processing temperature, etc., of the rotor material 1. For example, as the set values in producing an aluminum or aluminum alloy rotor R having a diameter of 40 to 70 mm and a height of 30 to 60 mm, a main load F: 270 to 325 MPa, a first sub-load F1 and second sub-load F2: 29 to 89 MPa can be exemplified.
[0075] Further, if the first sub-load F1 and the second sub-load F2 are set too small, there is a possibility that the excess thickness portion 5 and 6 will be torn off. To the contrary, if they are set too large, the effects of reducing the force to be applied to the center pin 16 and the force to be applied to the vane portion 13 reduce. As mentioned above, in the case of forging the aluminum alloy rotor R, it is preferably set the first sub-load F1 and the second sub-load F2 so as to fall within the range of 29 to 89 MPa, more preferably 39 to 49 MPa, respectively. In the case of using a spring-type sub-load applying means such as a gas cushion 45, the first sub-load F1 and the second sub-load F2 increase as the upper die 30 goes downward. The load within the aforementioned preferable range is an initial load.
[0076] A sub-load applying means for applying the first sub-load F1 and the second sub-load F2 is not specifically limited, but it is preferable to useameans which can apply a load in accordance with the raising and lowering operation of the upper die 30. From this aspect, a spring-type means such as a gas cushion is preferably used. As other sub-load applying means, a mechanical type spring, a hydraulic mechanism, and a shock absorber can be exemplified.
<PUNCHING STEP>
[0077] Fig. 14 is a cross-sectional view schematically showing a punching device (die set) as an excess thickness portion removing device used in the punching step (excess thickness portion removing step) . As shown in this figure, this punching device is equipped with a lower die 8 and an upper die 9, and configured to punch out the excess thickness portions 5 and 6 from the rotor material 1 by punching processing.
[0078] The lower die 8 is equipped with a lower plate 81 and a lower die body 85 disposed on the upper surface of the lower plate 81.
[0079] The lower plate 81 has, at its center portion, an excess thickness portion discharging hole 82 penetrated in the up-and-down direction. Further, at both side portions of the lower plate 81, guide bars 83 are formed so as to extend in the vertical direction.
[0080] The lower die body 85 is fixed to the upper surface of the lower plate 81 so as to close the excess thickness discharging hole 82.
[0081] The lower die body 85 is provided with a work mounting portion 86 corresponding to the excess thickness discharging hole 82 of the lower plate 81. The work mounting portion 86 is configured such that the rotor material 1 can be mounted with its one end face 2a facing downward. In detail, in this work mounting portion 86, a center hole side punch-out hole 87 is formed corresponding to the center hole side excess thickness portion 5 and a vane groove side punch-out hole 88 is formed corresponding to the vane groove side excess thickness portion 6. This center hole side punch-out hole 87 is formed to have an inner peripheral shape corresponding to the outer peripheral shape of the center hole side excess thickness portion 5, so that the center hole side excess thickness portion 5 can be fitted therein in a closely fitted manner. Further, the vane groove side punch-out holes 88 are formed to have an inner peripheral shape corresponding to the outer peripheral shape of the vane groove side excess thickness portion 6, so that the vane groove excess thickness portion 6 can be fitted therein in a closely fitted manner. Further, each punch-out hole 87 and 88 is penetrated in the up-and-down direction, and the lower end side thereof is communicated with the excess thickness discharging hole 82.
[0082] It is configured such that the rotor material 1 can be set on the work mounting portion 86 in a positioned state by fitting the excess thickness portions 5 and 6 of the rotor material 1 in the punch-out holes 87 and 88 in a closely fitted manner, respectively, and disposing one end face 2a of the rotor portion 2 on the work mounting portion 86.
[0083] The upper die 9 is equipped with an upper plate 91 and an upper die body 95 disposed on the lower surface of the upper plate 91.
[0084] The upper plate 91 is configured to move upward and downward in the vertical direction by being driven upward and downward by a lifting and lowering driving means such as a hydraulic cylinder (not illustrated).
[0085] Further, at both side ends of the upper plate 91, guide holes 93 are formed corresponding to the guide bars 83 of the lower plate 81. As will be described later, when the upper plate 91 is moved downward, the guide bars 83 are inserted in the guide holes 93 to guide the descending movement of the upper plate 91.
[0086] The upper die body 95 is fixed to the lower surface of the upper plate 91 so as to face the lower die body 85.
[0087] A center hole side blanking punch 97 and vane groove side blanking punches 98 are attached to the upper die body 95 in a downwardly protruded manner, corresponding to the center hole side punch-out hole 87 and the vane groove side punch-out holes 88, respectively, i.e., corresponding to the center hole 3 and vane grooves 4 of the rotor material 1 set to the lower die 85.
[0089] Next, a method of removing the excess thickness portions 5 and 6 of the rotor material 1 using the punching device structured mentioned above will be explained.
[0090] Initially, the rotor material 1 is mounted on the work mounting portion 86 of the lower die 8 of the punching device with the one end face 2a facing downward in a state in which each excess thickness portion 5 and 6 is fitted in the corresponding punch-out hole 87 and 88. In this mounted state, the center hole side blanking punch 97 and vane groove side blanking punch 98 of the upper die body 85 are arranged so as to face the other end side openings of the center hole 3 and vane grooves 4 of the rotor material 1.
[0091] In a state in which the rotor material 1 is set, when the upper die 85 is moved downward, the punches 97 and 98 of the upper die body 85 are inserted into the center hole 3 and vane grooves 4 from the upper end face (the other end face 2b) side of the rotor material 1 and each punch 97 and 98 hits against the excess thickness portion 5 and 6 in a pressed state. Thus, the excess thickness portions 5 and 6 are punched out. With this, the excess thickness portions 5 and 6 arc removed from the rotor portion 2, and the removed excess thickness portions 5 and 6 are discharged below via the excess thickness portion discharging hole 82. Thus, as shown in Fig. 14, one end side of the center hole 3 and that of the vane groove 4 of the rotor material 1 are opened, so that a rotor R in which both ends of the center hole 3 and the vane groove 4 are opened can be obtained.
[0092] In this embodiment, since the radius difference D5 between the excess thickness portion 5 and the center hole 3 and the radius difference D6 between the excess thickness portion 6 and the vane groove 4 are set to be small, respectively, the excess thickness portions 5 and 6 can be removed accurately at predetermined positions with a high degree of accuracy.
[0093] Especially, in this embodiment, since the excess thickness portion (5) (6) is formed to have a short breaking length (D3) (D4), the breaking area at the time of removing the excess thickness portion can be reduced, enabling easy removal of the excess thickness portion with a low load, which in turn can improve the production efficiency.
[0094] Furthermore, since the excess thickness portions 5 and 6 can be punched out by the punches 97 and 98 with a low load, it is possible to effectively prevent generation of harmful cracks and/or breakages in the rotor R. Thus, a high quality rotor product can be produced.
[0095] In addition, the processing can be performed with a low load, and therefore the abrasion of the punches 97 and 98 themselves can also be reduced, which can improve the durability of the punches 97 and 98. This in turn can further improve the durability of the punching device.
[0096] Furthermore, since the breakage area at the time of removing the excess thickness portion is small, the fracture remain (fracture surface) also becomes small. Thus, the adverse effects by the fracture remain can be avoided. Therefore, for example, it is not required to perform finish processing for finishing the fracture remain at the post-step, resulting in reduced steps, which can further improve the productivity and reduce the production cost.
[0097] Further, in this embodiment, one ends 3a and 4a of the center hole 3 and the vane grooves 4 are positioned inner than one end face 2a of the rotor portion 2, and therefore the fraction remains after the removals of the excess thickness portions are positioned at the inner peripheries of the center hole 3 and vane groove 4. Also in this regard, adverse effects by the fracture remains can be prevented, making the post-finishing processing for the fracture remains unnecessary, which can further improve the productivity.
[0098] Furthermore, in this embodiment, among the radius differences between the excess thickness portion 6 and the vane groove 4, the radius difference D61 at the rotor portion outer peripheral side end portion and the radius difference D62 at the rotor portion inner peripheral side end portion are formed to be thicker than the radius difference D60 at the intermediate main portion. Therefore, after the forge processing but before the punching processing, improper dropping of the excess thickness portion 6 can be prevented. For example, such a problem that the excess thickness portion 6 remains in the forge processing die can be prevented assuredly, which can maintain the high productivity.
[0099] In addition, in this embodiment, since both end portions of the excess thickness portion 6 are formed to have large radius differences D61 and D62, improper breakage of these portions can be prevented assuredly, which can more assuredly prevent improper dropping of the excess thickness portion 6. In other words, both end portions of the excess thickness portion 6 often become breakage starting points at the time of dropping. Therefore, by forming both end portions to be thick, it becomes hard to cause the breakage, which prevents improper dropping more assuredly.
[0100] Furthermore, in this embodiment, the radius difference (clearanceD6) of the outer periphery of the excess thickness portion 6 at the side of the vane groove 4 is partially increased. The present invention, however, is not limited to the above, and allows partially increasing the radius difference D5 of the outer periphery of the excess thickness portion 5 at the side of the center hole 3.
[0101] In this embodiment, if the radius difference D5 and D6 of the outer periphery of the excess thickness portion and/or the breaking length D3 and D4 is too large, the excess thickness portion 5 and 6 cannot be removed with a high degree of accuracy at the punching processing, which may cause adverse effects by the fracture remains. To the contrary, if the radius difference D5 and D6 is too small, the excess thickness portion 5 and 6 may improperly drop before the punching processing.
[0102] Furthermore, in cases where the breaking length D3 (or D4) is minus, i.e., one end face 3a (or 4a) of the center hole 3 (or the vane groove 4) is positioned outer than one end face 2a of the rotor portion 2 and inside the excess thickness portion 5 (or 6), even if the thickness portion 5 (or 6) is removed by punching processing, a part of the peripheral wall of the excess thickness portion 5 (or 6) remains and the remainedportion (fracture remain) will be positioned so as to protrude outward of the rotor R. For this reason, it is required to remove the protruded fracture remain at the post-processing, increasing the number of steps, which may cause deterioration of the productivity, and therefore it is not preferable.
[0103] In this embodiment, the punching processing is performed as cold working since it is not especially required to heat the rotor material 1. In the present invention, however, the punching processing can be performed as hot processing by heating the rotor material 1 immediately before performing the punching processing.
<MODIFIED EMBODIMENT>
[0104] In the aforementioned embodiment, the excess thickness portions 5 and 6 are punched out by the punches 97 and 98 inserted from the other end side of the center hole 3 and vane grooves 4. In the present invention, however, the removal processing of the excess thickness portions is not limited to the blanking processing by a punch.
[0105] That is, it can be configured such that an impact member such as a hammer is hit against the excess thickness portion from the outside of the rotor material 1, for example, in a direction perpendicular to the axis direction to remove the excess thickness portion by the impacts, or the basal end (base end portion) of the excess thickness portions 5 and 6 is cut (sheared) along the plane perpendicular to the axial direction using an impact member such as a cutting tool.
EXAMPLES
[EXAMPLE 1]
[0106] A rotor material 1 shown in Fig. 3 was forged using a forging dies 10 and 30 shown in Figs. 1 and 2. The rotor material 1 was a material for producing an aluminum alloy rotor R shown in Fig. 4.
[0107] The rotor R had an outer diameter: 52 mm, a height: 50 mm, a diameter of the center hole 3: 10 mm, the number of vane grooves 4: 5, a groove width: 3 mm, a groove depth: 15 mm, an offset dimension U: 10 mm. The material alloy was A390 aluminum alloy.
[0108] As shown in the following Table 1, in the forging die, the clearance D5 between the center pin 16 of the lower die 10 and the circular hole 35 of the upper die 35 was set to 0.1 mm, and the clearance D6 between the vane portion 13 of the lower die 10 and the flat hole 36 of the upper die 30 was also set to 0.1 mm in the same manner as mentioned above.
[0109] Furthermore, the distance (breaking length D3) between the center pin 16 of the lower die 10 and the opening face of the circular hole 35 of the upper die 30 was set to 1.5 mm, and the distance (breaking length D4) between the vane portion 13 of the lower die 10 and the opening face of the flat hole 36 of the upper die 30 was also set to 1.5 mm in the same manner as mentioned above.
[0110] Then, a forging raw material W heated to 400 °C was mounted in the lower die 10 and formed into a rotor material 1 by applying the following forming loads . During this forging, the first sub-load F1 and the second sub-load F2 increased. Each of the final loads was 1.5 times of each initial load.
Main load F=325 MPa
[0111]
Initial load of the first sub-load F1: 32.9 MPa (4.0 kg/mm2)
Initial load of the second sub-load F2: 44.1 MPa (4.5 kg/mm2)
[0112] The excess thickness portions 5 and 6 were removed from the obtained rotor material 1 using the punching device shown in Fig. 14 to thereby obtain a rotor R.
[0113] The material yielding percentage of the rotor R with respect to the forging raw material W (weight of the rotor R / weight of the forging material W x 100) was 82.9 %.
| D3, D4 | D5, D6 | Fracture during forging | Fracture position | Fracture area | |
| Example 1 | 1.5 mm | 0.1 mm | Nil | Inner periphery | Small |
| Example 2 | 0 | 0.1 mm | Nil | Inner periphery | Small |
| Comparative Example 1 | -2 mm | 0.1 mm | Yes | Outer periphery | Small |
| Comparative Example 2 | -2 mm | 2 mm | Nil | Outer periphery | Large |
[EXAMPLE 2]
[0114] As shown in Fig. 1, a rotor R was produced in the same manner as in the aforementioned Example 1 except that the breaking lengths D3 and D4 of the excess thickness portions 5 and 6 were set to "0 (zero)," respectively.
[COMPARATIVE EXAMPLE 1]
[0115] As shown in Table 1, a rotor R was produced in the same manner as in the aforementioned Example except that the breaking lengths D3 and D4 of the excess thickness portions 5 and 6 were set to "-2 mm," respectively.
[COMPARATIVE EXAMPLE 2]
[0116] As shown in Table 1, a rotor R was produced in the same manner as in the aforementioned Example except that the breaking lengths D3 and D4 of the excess thickness portions 5 and 6 were set to "-2 mm," respectively, and that the clearances D5 and D6 of the outer periphery of the excess thickness portions 5 and 6 were set to "2 mm," respectively.
[EVALUATION]
[0117] As shown in Table 1, in the production methods of Examples 1 and 2, no breakage and/or dropping of the excess thickness portions 5 and 6 was occurred during the forge processing, and therefore the processing could be completed without any delay.
[0118] Furthermore, in the production methods of Examples 1 and 2, the fracture surface after the punching processing (after removal of the excess thickness portions) was small, and the fracture remain (fracture cross-section) was formed in the center hole 3 and the vane groove 4, respectively. Therefore, it is considered that there is no problem even if no finishing processing of the fracture remain is performed.
[0119] On the other hand, in the production method of Comparative Example 1, the excess thickness portions 5 and 6 were broken improperly during the forge processing. Thus, the processing could not be performed smoothly.
[0120] Furthermore, in the production method of Comparative Example 2, the fracture cross-section after the punching processing was large, and the fracture remain (fracture cross-section) was positioned so as to protrude outward. Therefore, in the case of the practical usage, it is considered to remove the fracture remains by finish processing.
[TEST EXAMPLES 1-7]
[0121] Rotors R were produced in the same conditions as in the aforementioned Example 1 except that the curvature radiuses r3 and r3a of the center hole 3 were adjusted to the values as shown in Table 2. Then, the inner burrs, and protruded burrs (see Fig. 13B) were evaluated. The results are also shown in Table 2.
| r3 [mm] | r3a [mm] | Average height of protruded burrs [mm] | Variation of protruded burrs | Average height of inner burrs [mm] | |
| Test Example 1 | 1 | 0.1 | 0.1 | Small | 0.5 |
| Test Example 2 | 1 | 0.5 | 0.5 | Small | 0.5 |
| Test Example 3 | 1 | 1 | 1 | Small | 0.5 |
| Test Example 4 | 0.5 | 0.1 | 0.1 | Small | 0.3 |
| Test Example 5 | 0.2 | 0.1 | 0.1 | Small | 0.1 |
| Test Example 6 | 0.2 | 0.5 | 0.5 | Medium | 0.1 |
| Test Example 7 | 2 | 1 | 1 | Small | Fracture position was unstable |
[0122] As will be apparent from the above Table, in the products in which the curvature radiuses r3 and r3a were adjusted to a specific value, the status of inner burrs and protruded burrs was stable.
[0123] As to the products having vane groove 4 side curvature radiuses r4 andr4a, the same tests as mentioned above were per formed, resulting in the same evaluation.
[0124] This application claims priorities to Japanese Patent Application No. 2008-164327 filed on June 24, 2008, and Japanese Patent Application No. 2009-44372 filed on February 26, 2009, the entire disclosure of each of which is incorporated herein by reference in its entirety.
[0125] It should be understood that the terms and expressions used herein are used for explanation and have no intention to be used to construe in a limited manner, do not eliminate any equivalents of features shown and mentioned herein, and allow various modifications falling within the claimed scope of the present invention.
[0126] While the present invention may be embodied in many different forms, a number of illustrative embodiments are described herein with the understanding that the present disclosure is to be considered as providing examples of the principles of the invention and such examples are not intended to limit the invention to preferred embodiments described herein and/or illustrated herein.
[0127] The limitations in the claims are to be interpreted broadly based on the language employed in the claims and not limited to examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive.
INDUSTRIAL APPLICABILITY
[0128] The method for forging a rotor material according to the present invention can be applied in producing a rotor, for example for a compressor.
BRIEF DESCRIPTION OF THE REFERENCE NUMERALS
[0129]
- 1:
- rotor material
- 3:
- center hole (shaft hole)
- 4:
- vane groove
- 10:
- lower die
- 12:
- forming hole
- 13:
- vane portion
- 16:
- center pin
- 30:
- upper die
- 35:
- circular hole (center pin corresponding hole)
- 36:
- flat hole (vane portion corresponding hole)
- 40:
- cylindrical pin (back-pressure pin)
- 41:
- flat plate (back-pressure plate)
- D3:
- center hole side end face difference
- D4:
- vane groove side end face difference
- D5:
- center hole side clearance
- D6:
- vane groove side clearance
- R:
- rotor
- W:
- forging raw material
wherein the lower die (10) has a vane groove forming vane portion (13) protruded in a forming hole (12), and a center hole forming center pin (16) to be arranged in a center of the forming hole (12),
characterized in that
the upper die (30) has an upper die body (31) for applying a main load (F) to portions on an upper end of a forging raw material (W) not corresponding to the center pin (16) and the vane portion (13) of the lower die (10), a back-pressure pin (40) fitted in a center pin corresponding hole (35) formed in the upper die body (31) in an advanceable and retractable manner, the back-pressure pin (40) being configured to apply a first sub-load (F1) to a portion on an upper end of a forging raw material (W) corresponding to the center pin (16), and a back-pressure plate (41) fitted in a vane portion corresponding hole (36) formed in the upper die body (31) in an advanceable and retractable manner, the back-pressure plate (41) being configured to apply a second sub-load (F2) to a portion on an upper end of a forging raw material (W) corresponding to the vane portion (13), wherein the main load (F), the first sub-load (F1) and the second sub-load (F2) can be set independently; and
wherein an upper end face of the vane portion (13) is arranged so as to coincide with or distance from a lower end face of the vane portion corresponding hole (36) at the time of die matching.
preparing a lower die (10) having a vane groove forming vane portion (13) protruded in a forming hole (12), and a center hole forming center pin (16) to be arranged in a center of the forming hole (12); and
preparing an upper die (30)
characterized by
preparing such an upper die (30) which includes an upper die body (31) for applying a main load (F) to portions on an upper end of a forging raw material (W) not corresponding to the center pin (16) and the vane portion (13) of the lower die (10), a back-pressure pin (40) fitted in a center pin corresponding hole (35) formed in the upper die body (31) in an advanceable and retractable manner, the back-pressure pin (40) being configured to apply a first sub-load (F1) to a portion on an upper end of a forging raw material (W) corresponding to the center pin (16), and a back-pressure plate (41) fitted in a vane portion corresponding hole (36) formed in the upper die body (31) in an advanceable and retractable manner, the back-pressure plate (41) being configured to apply a second sub-load (F2) to a portion on an upper end of a forging raw material (W) corresponding to the vane portion (13),
wherein the main load (F), the first sub-load (F1) and the second sub-load (F2) are set independently, and
wherein an upper end face of the vane portion (13) is arranged so as to coincide with or distance from a lower end face of the vane portion corresponding hole (36) at the time of die matching.
wobei das untere Formwerkzeug (10) einen flügelnutformenden Flügelabschnitt (13), welcher in ein Formgebungsloch (12) hinein vorsteht, und einen mittellochformenden Mittelstift (16), welcher in einem Zentrum des Formgebungslochs (12) anzuordnen ist, aufweist,
gekennzeichnet dadurch, dass
das obere Formwerkzeug (30) aufweist einen Oberer-Formwerkzeug-Körper (31) zum Aufbringen einer Hauptlast (F) auf Abschnitte an einem oberen Ende eines Schmiederohmaterials (W), welche nicht mit dem Mittelstift (16) und dem Flügelabschnitt (13) des unteren Formwerkzeugs (10) korrespondieren, einen Gegendruckstift (40), welcher in ein mit dem Mittelstift korrespondierendes Loch (35), das in dem Oberer-Formwerkzeug-Körper (31) ausgebildet ist, vorschiebbar und zurückschiebbar eingebracht ist, wobei der Gegendruckstift (40) dazu eingerichtet ist, eine erste Sublast (F1) auf einen Abschnitt an einem oberen Ende eines Schmiederohmaterials (W), welcher mit dem Mittelstift (16) korrespondiert, aufzubringen, und eine Gegendruckplatte (41), welche in ein mit dem Flügelabschnitt korrespondierendes Loch (36), welches in dem Oberer-Formwerkzeug-Körper (31) ausgebildet ist, vorschiebbar und zurückschiebbar eingebracht ist, wobei die Gegendruckplatte (41), dazu eingerichtet ist, eine zweite Sublast (F2) auf einen Abschnitt an einem oberen Ende eines Schmiederohmaterials (W), welcher mit dem Flügelabschnitt (13) korrespondiert, aufzubringen, wobei die Hauptlast (F), die erste Sublast (F1) und die zweite Sublast (F2) unabhängig voneinander einstellbar sind; und
wobei eine obere Stirnfläche des Flügelabschnitts (13) angeordnet ist, so dass sie zur Zeit der Formwerkzeugpaarung zusammentrifft mit oder im Abstand ist von einer unteren Stirnfläche des mit dem Flügelabschnitt korrespondierenden Lochs (36) .
Vorbereiten eines unteren Formwerkzeugs (10), welches einen flügelnutformenden Flügelabschnitt (13), welcher in ein Formgebungsloch (12) hinein vorsteht, und einen mittellochformenden Mittelstift (16), welcher in einem Zentrum des Formgebungslochs (12) anzuordnen ist, aufweist; und
Vorbereiten eines oberen Formwerkzeugs (30)
gekennzeichnet durch
Vorbereiten solch eines oberen Formwerkzeugs (30), welches aufweist einen Oberer-Formwerkzeug-Körper (31) zum Aufbringen einer Hauptlast (F) auf Abschnitte an einem oberen Ende eines Schmiederohmaterials (W), welche nicht mit dem Mittelstift (16) und dem Flügelabschnitt (13) des unteren Formwerkzeugs (10) korrespondieren, einen Gegendruckstift (40), welcher in ein mit dem Mittelstift korrespondierendes Loch (35), das in dem Oberer-Formwerkzeug-Körper (31) ausgebildet ist, vorschiebbar und zurückschiebbar eingebracht ist, wobei der Gegendruckstift (40) dazu eingerichtet ist, eine erste Sublast (F1) auf einen Abschnitt an einem oberen Ende eines Schmiederohmaterials (W), welcher mit dem Mittelstift (16) korrespondiert, aufzubringen, und eine Gegendruckplatte (41), welche in ein mit dem Flügelabschnitt korrespondierendes Loch (36), welches in dem Oberer-Formwerkzeug-Körper (31) ausgebildet ist, vorschiebbar und zurückschiebbar eingebracht ist, wobei die Gegendruckplatte (41), dazu eingerichtet ist, eine zweite Sublast (F2) auf einen Abschnitt an einem oberen Ende eines Schmiederohmaterials (W), welcher mit dem Flügelabschnitt (13) korrespondiert, aufzubringen,
wobei die Hauptlast (F), die erste Sublast (F1) und die zweite Sublast (F2) unabhängig voneinander eingestellt werden, und
wobei eine obere Stirnfläche des Flügelabschnitts (13) angeordnet wird, so dass sie zur Zeit der Formwerkzeugpaarung zusammentrifft mit oder im Abstand ist von einer unteren Stirnfläche des mit dem Flügelabschnitt korrespondierenden Lochs (36) .
dans lequel la matrice inférieure (10) présente une partie ailette de formage de rainure (13) qui fait saillie dans un trou de formage (12), et une broche centrale de formage de trou central (16) destinée à être agencée au centre du trou de formage (12) ;
caractérisé en ce que :
la matrice supérieure (30) présente un corps de matrice supérieure (31) destiné à appliquer une charge principale (F) à des parties situées sur une extrémité supérieure d'une matière première de pièce de forge (W) qui ne correspond ni à la broche centrale (16) ni à la partie ailette (13) de la matrice inférieure (10), une broche de contre-pression (40) adaptée dans un trou correspondant de la broche centrale (35), formé dans le corps de matrice supérieure (31) d'une façon à pouvoir s'avancer et se rétracter, la broche de contre-pression (40) étant configurée de façon à appliquer une première charge secondaire (F1) sur une partie située sur une extrémité supérieure d'une matière première de pièce de forge (W) qui correspond à la broche centrale (16), et une plaque de contre-pression (41) adaptée dans un trou correspondant de la partie ailette (36), formé dans le corps de matrice supérieure (31) d'une façon à pouvoir s'avancer et se rétracter, la plaque de contre-pression (41) étant configurée de façon à appliquer une seconde charge secondaire (F2) sur une partie située sur une extrémité supérieure d'une matière première de pièce de forge (W) correspondant de la partie ailette (13), dans lequel la charge principale (F), la première charge secondaire (F1) et la seconde charge secondaire (F2) peuvent être déterminées de manière indépendante ; et
dans lequel une face d'extrémité supérieure de la partie ailette (13) est agencée de façon à coïncider avec une face d'extrémité inférieure du trou correspondant de la partie ailette (36), ou à se situer à une distance de celle-ci, au moment du montage de la matrice.
préparer une matrice inférieure (10) qui présente une partie ailette de formage de rainure (13) qui fait saillie dans un trou de formage (12), et une broche centrale de formage de trou central (16) destinée à être agencée au centre du trou de formage (12) ; et
préparer une matrice supérieure (30) ;
caractérisé par une étape consistant à :
préparer une telle matrice supérieure (30) qui comprend un corps de matrice supérieure (31) destiné à appliquer une charge principale (F) à des parties sur une extrémité supérieure d'une matière première de pièce de forge (W) qui ne correspond ni à la broche centrale (16) ni à la partie ailette (13) de la matrice inférieure (10), une broche de contre-pression (40) adaptée dans un trou correspondant de la broche centrale (35), formé dans le corps de matrice supérieure (31) d'une façon à pouvoir s'avancer et se rétracter, la broche de contre-pression (40) étant configurée de façon à appliquer une première charge secondaire (F1) sur une partie située sur une extrémité supérieure d'une matière première de pièce de forge (W) qui correspond à la broche centrale (16), et une plaque de contre-pression (41) adaptée dans un trou correspondant de la partie ailette (36), formé dans le corps de matrice supérieure (31) d'une façon à pouvoir s'avancer et se rétracter, la plaque de contre-pression (41) étant configurée de façon à appliquer une seconde charge secondaire (F2) sur une partie située sur une extrémité supérieure d'une matière première de pièce de forge (W) correspondant de la partie ailette (13) ;
dans lequel la charge principale (F), la première charge secondaire (F1) et la seconde charge secondaire (F2) peuvent être déterminées de manière indépendante ; et
dans lequel une face d'extrémité supérieure de la partie ailette (13) est agencée de façon à coïncider avec une face d'extrémité inférieure du trou correspondant de la partie ailette (36), ou à se situer à une distance de celle-ci, au moment du montage de la matrice.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.
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