Forging device

Abstract

The invention provides a forging device capable of simplifying or reducing the size of the structure. A sliding member that protrudes and retreats in a direction orthogonal to the vertical movement direction of the punch in a region in which the punch moves up and down is provided inside the lower mold, and a cam surface that makes contact with the sliding member and moves to a position where the sliding member retreats from the region and a position where the sliding member protrudes toward the region is provided on the outer peripheral surface of the punch. A connecting member acting together with the sliding member is provided inside the lower mold together with the sliding member, and the stripper is configured so as to be attached to the connecting member and to be moved by the connecting member to a position engaged with the workpiece and a retracted position separated from the workpiece.

Description

Technical Field

[0001] The present invention relates to an apparatus for forging a workpiece using an upper mold and a lower mold, and more particularly to a forging apparatus having a stripper for detaching the workpiece from the upper mold. Background Technology

[0002] Forging is a process in which a load is applied to a workpiece to give it a specified shape, thus the workpiece is attached to an upper or lower die. Therefore, a stripper or ejector is needed in the forging apparatus to remove the workpiece from the die. Patent Document 1 describes a forging die having a mechanism for such stripping and a mechanism for ejection.

[0003] Patent Document 1 describes a forging die that forms a workpiece into a predetermined shape using a die in the lower die and a punch in the upper die, and is used to pierce the center portion. A stripper is mounted on the upper die, movable up and down, to press the flange of the workpiece against the lower die side. Specifically, the stripper is mounted on the lower end of a rod, which is held by the upper die to allow it to move up and down. A spring is further provided to press the stripper downwards from the upper die. On the other hand, an ejector pin, movable up and down by a predetermined drive mechanism, is positioned below the die in the lower die. In the forging die described in Patent Document 1, after the upper die descends to its bottom dead center and performs the predetermined processing on the workpiece, the stripper maintains the workpiece pressed against the lower die side by spring force during the upward movement of the upper die. That is, the workpiece is stripped from the upper die by the stripper descending relative to the upper die. Then, the ejector pin rises by a predetermined drive mechanism, ejecting the workpiece from the lower die.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2006-326665 Summary of the Invention

[0005] The device described in Patent Document 1 is configured as a forging die that straightens the flange of the workpiece during forging. Therefore, a straightening retainer that presses the ejector towards the flange is positioned on the back (upper) side of the ejector. With this straightening retainer, the ejector firmly presses the flange to perform the straightening during the upward movement of the upper die. Thus, in the structure described in Patent Document 1, the ejector must be located on the upper die. In contrast, since ejecting the workpiece occurs after the upper die has risen to its top dead center and stopped moving, the ejector pin or its driving mechanism must be provided separately from the upper die or the ejector. That is, in conventional devices such as the forging die described in Patent Document 1, the ejector or ejector used to remove the workpiece from the forging die, along with its driving mechanism, are provided separately. Therefore, the overall structure of the device becomes complex and potentially large-scale, and there is still room for improvement from this perspective. Furthermore, it is possible to configure a structure that links the mechanism for the stripper with the mechanism for the ejector, but even with such a structure, there is still room for developing new structures in order to simplify the overall structure of the device or to miniaturize it.

[0006] This invention was made in view of the above-mentioned technical problems, and its purpose is to provide a forging device that can achieve a simplified or miniaturized structure.

[0007] To achieve the above objectives, the forging apparatus of the present invention comprises: an upper die and a lower die, which apply pressure to a workpiece to produce plastic deformation, thereby forming it into a predetermined shape; a stripper that engages with the workpiece which is attached to the upper die and rises, and pulls the workpiece down relative to it, thereby detaching the workpiece from the upper die; and an ejector that lifts the workpiece from below, thereby detaching the workpiece from the lower die. The forging apparatus is characterized in that a sliding member, which protrudes and retracts in a direction orthogonal to the vertical movement direction of the ejector, is disposed inside the lower die in the region where the ejector moves vertically; and a cam surface is provided on the outer peripheral surface of the ejector to cause the sliding member to contact and move to a position retracting from the region and a position protruding into the region; a connecting member that operates together with the sliding member is disposed inside the lower die together with the sliding member; and the stripper is configured to be mounted on the connecting member and moved by the connecting member to a position engaging with the workpiece and a retracted position separated from the workpiece.

[0008] In this invention, a plurality of the peelers may be arranged at equal intervals on the outer periphery of the workpiece on a circumference centered on the workpiece.

[0009] In this invention, the cam surface may be as follows: the cam surface has a lowermost end, and the portion upward from the lowermost end becomes an inclined surface that recedes from the outer peripheral surface of the ejector toward the center side, and the lowermost end is formed on the outer peripheral surface of the ejector in such a way that it is located at a position higher than the sliding member when the workpiece is engaged with the stripper by the ejector.

[0010] In this invention, the following configuration is provided: the connecting member is composed of a rotating shaft member that is held inside the lower shape in the vertical direction and rotates about a central axis in the vertical direction; the sliding member is configured to be installed at the lower end of the rotating shaft member, and by rotating together with the rotating shaft member, a portion of the front end protrudes into the area and retracts; the peeler is configured to be installed at the upper end of the rotating shaft member, and by rotating together with the rotating shaft member, a portion of the front end protrudes into the position where it engages with the workpiece and retracts.

[0011] Invention Effects

[0012] In this invention, if the upper mold descends to the bottom dead center and the forging of the workpiece is completed, the ejector also descends to the bottom dead center, and the cam surface provided on its outer peripheral surface descends to the position of the sliding member, thus the sliding member moves towards the center side of the ejector. Subsequently, the stripper, connected to the sliding member via a connecting member, moves to a position where it engages with the workpiece. Therefore, if the workpiece attached to the upper mold is pulled to the position of the stripper, the stripper engages with the workpiece and prevents it from rising. That is, the stripper pulls the workpiece relative to the upper mold, and the workpiece is separated from the upper mold. Then, the ejector rises, causing the sliding member and the stripper to retract to their original positions. Thus, the ejector moves the stripper back and forth relative to the workpiece by rising and falling, thus combining the function of ejecting the workpiece and driving the stripper to separate the workpiece from the upper mold. Therefore, according to this invention, the required components can be reduced, simplifying or miniaturizing the overall structure.

[0013] In a structure in which the peelers are arranged at equal intervals on the outer periphery of the workpiece in its circumferential direction, the pull-down force can be applied evenly to the workpiece, thus allowing the workpiece to be smoothly pulled out from the top without tilting. Attached Figure Description

[0014] Figure 1 This is a schematic cross-sectional view of an embodiment of the present invention.

[0015] Figure 2 It is a schematic three-dimensional view representing a set of peelers and sliding components.

[0016] Figure 3 This is a partial sectional view showing the sliding component, the cam surface, and the mechanism that presses the sliding component.

[0017] Figure 4A It is a diagram used to illustrate the function of the forging device, and it is a top view and a sectional view showing the state during the forming process.

[0018] Figure 4B It is a diagram used to illustrate the function of the forging device, and it is a top view and a sectional view showing the state of descending to the bottom dead center.

[0019] Figure 4C It is a diagram used to illustrate the function of the forging device, and it is a top view and a sectional view showing the state of the workpiece being pulled down from the upper mold by the stripper.

[0020] Figure 4D It is a diagram used to illustrate the function of the forging device, and it is a top view and a sectional view showing the state of the workpiece being ejected by the ejector. Detailed Implementation

[0021] Next, embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, the embodiments described below are merely examples of how the present invention is implemented and do not limit the scope of the invention.

[0022] Figure 1 The image shows an example of a forging apparatus 1 according to the present invention as a schematic cross-sectional view. The example shown here is an apparatus mainly configured to apply pressure to a cup-shaped hollow portion 3 provided on a workpiece 2 to produce plastic deformation, thereby shaping its inner and outer peripheral surfaces into a predetermined shape. It is mainly composed of a lower mold 4, an upper mold 5, and an ejector (sometimes simply referred to as an ejector) 6.

[0023] The lower type 4 has a base portion 7 that can be movably accommodated for the ejector 6. A through portion 8 with a circular cross-section along the vertical direction is provided in the base portion 7, and the ejector 6 is accommodated inside it. The inner peripheral surface of the upper end of the through portion 8 becomes a machined surface 9 that slides in contact with the outer peripheral surface of the hollow portion 3 in the workpiece 2 and bears the load that presses the inner peripheral surface of the hollow portion 3 outward in the radial direction.

[0024] A plate member 10 with a through hole forming the same as the through portion 8 is fixed on the upper surface of the base portion 7, and a mold 11 is mounted on it. The mold 11 is used to process the outer peripheral surface of the hollow portion 3 in the workpiece 2 and has an inner peripheral shape corresponding to the product shape of the hollow portion 3.

[0025] The upper type 5 includes a plurality of segmented types 12 that are inserted into the hollow portion 3 of the workpiece 2 and open outward in the radial direction, and a sliding type 13 that is inserted into the interior of the segmented types 12 and presses the segmented types 12 from the inside to the outside. The sliding type 13 has a conical outer peripheral surface, so that its conical portion contacts the inner peripheral surface of the segmented type 12, and in this state, it descends relative to the segmented type 12, thereby expanding the segmented type 12. Furthermore, the lower end of the sliding type 13 is configured to abut against the center of the inner peripheral surface of the hollow portion 3 in the workpiece 2 to form the inner peripheral surface of the hollow portion 3.

[0026] The ejector 6 is a cylindrical component that fits into the shaft portion 14 of the workpiece 2, and is held in place by being inserted into the through portion 8 provided in the base portion 7, allowing it to move up and down. Furthermore, the upper end of the ejector 6 is shaped to abut against the outer peripheral surface of the hollow portion 3 in the workpiece 2. The upper end of a rod 15 inserted from below abuts against the lower end surface of the ejector 6. The ejector 6 moves up and down by moving this rod 15 up and down via a drive unit (not shown).

[0027] In addition, Figure 1 In the text, the symbol "16" refers to the so-called pointed end face of the shaft portion 14 in the workpiece 2, which is a front end with a triangular cross-section, formed to create a central hole in the center of the end face of the shaft portion 14. This pointed end face 16 is held by a retaining plate 17 mounted on the lower end of the base portion 7. The aforementioned rod 15 passes through this retaining plate 17.

[0028] The base portion 7 constituting the lower type 4 is provided with a mechanism for separating the workpiece 2 from the upper type 5. When the upper type 5 rises, the workpiece 2 rises while attached to the upper type 5; therefore, a peeler 18 is provided to engage with the workpiece 2 and stop its rise. The peeler 18 is a plate-shaped component that moves between a position protruding from the inner circumference of the through portion 8 and a retracted position separated from the workpiece 2 within the through portion 8. A recess 19 is formed at the upper end of the base portion 7 and around the circumference of the through portion 8, causing the base portion 7 to be recessed. The peeler 18 is disposed inside this recess 19. Furthermore, the recess 19 is closed by the plate component 10.

[0029] Furthermore, multiple peelers 18 are provided at equal intervals along the circumference of the workpiece 2 or the through portion 8. Figure 1 In the example shown, the peeler 18 is generally rectangular or fan-shaped when viewed from above, and rotates around one end. A portion of the front end side (peripheral side of the fan shape) protrudes from the inner periphery of the through portion 8 and is held back by retraction.

[0030] The mechanism that rotates the peeler 18 is configured to make the ejector 6 function as a cam. Sliding members 20 are provided corresponding to each of the peelers 18. A receiving portion 21 with the same shape as the aforementioned recess 19 is formed in the middle portion of the lower type 4 in the vertical direction. This receiving portion 21 is configured, for example, to divide the base portion 7 vertically, and can be formed by cutting a portion of the divided portion. The receiving portion 21 is disposed on the lower side of each recess 19, so each sliding member 20 is disposed at a position consistent with the peeler 18 in the vertical direction.

[0031] As an example, the sliding member 20 is a plate-shaped component with approximately the same shape as the peeler 18. Each peeler 18 and the sliding member 20 located below it are connected as a whole by a connecting pin (or rod) 22, which is a connecting member or rotating shaft member that is configured to run vertically through the interior of the lower type 4 and rotate around a central axis, and thus rotate. Figure 2 The diagram schematically shows a set of peelers 18 and sliding parts 20 connected by connecting pins 22.

[0032] The sliding member 20 is configured to function as a cam follower. The lower surface of the portion ejected towards the inner periphery of the through-hole 8 is obliquely chamfered or machined into a curved surface, thereby ejecting it from below and generating a horizontal force to retract it from the through-hole 8. A cam surface is provided on the outer periphery of the sliding member 20 to cause it to retract in a radial direction centered on the workpiece 2 (orthogonal to the direction of vertical movement of the ejector 6). Figure 1 In the example shown, the groove 23 and the outer peripheral surface of the sliding member 20 become cam surfaces. That is, a groove 23 is formed along the vertical direction on the outer peripheral surface of the ejector 6 at a position corresponding to the sliding member 20. This groove 23 extends a predetermined length from the upper end of the ejector 6, and its lowermost end 23a is set at a position opposite to the sliding member 20 when the ejector 6 is lowered to the bottom dead center, or slightly lower than that position. Furthermore, regarding the depth of the groove 23, the stripper 18, connected to the connecting pin 22, rotates through the sliding member 20, and a portion of its front end is ejected into the interior of the through-hole 8, the ejection amount being set to engage with the workpiece 2 inside the through-hole 8. Moreover, as... Figure 3 As shown, the lower end of the groove 23 is formed as an inclined surface 23b that smoothly slopes or bends from the bottom of the groove 23 to the outer peripheral surface of the sliding member 20. This is because it is necessary to allow the sliding member 20 to move backward smoothly.

[0033] A clamping member is provided to move the sliding member 20 toward the ejector 6. For example... Figures 1 to 3As shown, the clamping component consists of an ejector plug 24 and a spring (elastic member) 25. Specifically, a mounting hole 26 extending from the outer peripheral surface of the lower part 4 is formed at a position corresponding to the front end of the sliding member 20. The ejector plug 24, which contacts the sliding member 20, and the spring 25, which presses the ejector plug 24 against the sliding member 20, are disposed inside the mounting hole 26. Furthermore, the sliding member 20, the connecting pin 22, the ejector plug 24, the spring 25, and the mounting hole 26 are all provided corresponding to each peeler 18, therefore, the same number of peelers 18 are provided.

[0034] Next, refer to Figure 4A , Figure 4B , Figure 4C , Figure 4D The function of the forging apparatus 1 described above will be explained. Furthermore, in Figures 4A to 4D The diagram shows a top view of six equally spaced strippers 18, viewed from above, and a diagram indicating the positions of the upper type 5, the ejector 6, and the strippers 18. Figure 1 Same sectional view.

[0035] Figure 4A This indicates the state after molding begins. In this state, the ejector 6 is lifted, and the workpiece 2 is placed on it. The upper mold 5 is inserted into the hollow portion 3 of the workpiece 2. As described above, the upper mold 5 consists of a segmented mold 12 and a sliding mold 13 inserted inside it. The segmented mold 12 is expanded by the sliding mold 13, thereby pressing the hollow portion 3 outward in the radial direction. Subsequently, the hollow portion 3 is pressed against the mold 11. In this state, by pressing the workpiece 2 down, the hollow portion 3 is processed into a predetermined shape by the lower mold 4 and the upper mold 5.

[0036] During this process, since the ejector 6 is lifted by the rod 15, the groove 23 formed on its outer peripheral surface is positioned higher than the sliding member 20. Therefore, the outer peripheral surface of the ejector 6, with an outer diameter approximately the same as the through portion 8, faces the sliding member 20, causing the sliding member 20 to retract from the through portion 8 by the ejector 6. The peeler 18, connected to the sliding member 20 via the connecting pin 22, faces the same direction as the sliding member 20; therefore, as the sliding member 20 retracts from the through portion 8, the peeler 18 also retracts in the same manner. Figure 4A As indicated by the arrow, it rotates and retracts from the through section 8 (i.e., the area where workpiece 2 moves up and down). Therefore, workpiece 2 is smoothly pressed and processed.

[0037] exist Figure 4B The image shows the upper part 5 or the ejector 6 descending to the bottom dead center. The upper end of the workpiece 2 is located lower than the position where the peeler 18 is located. Furthermore, the outer diameter of the segment 12 is smaller than the inner diameter of the through portion 8, so at the location where the peeler 18 is located, there is space for the peeler 18 to be ejected towards the through portion 8.

[0038] On the other hand, the groove 23 formed on the outer peripheral surface of the ejector 6 descends to a position opposite to the sliding member 20. Therefore, the sliding member 20 is pressed by the spring 25, and a portion of it enters the inner side of the through portion 8, i.e., the interior of the groove 23, and rotates. Figure 4B As indicated by the arrow, the peeler 18, which is connected to the sliding member 20 via the connecting pin 22, also rotates, so that a portion of the peeler 18 protrudes into the interior of the upper through-part 8 of the workpiece 2. This position of the peeler 18 is the position where it engages with the workpiece 2.

[0039] After workpiece 2 is machined, upper mold 5 rises from bottom dead center. In this case, since both segmented mold 12 and sliding mold 13 rise, workpiece 2, while attached to upper mold 5, is pulled up together with upper mold 5. This process is shown below. Figure 4C In the state where the upper mold 5 begins to rise, the ejector 6 stops at the bottom dead center, thus the sliding member 20 and the peeler 18 remain in a state where a portion of them is pushed out towards the inside of the through portion 8. Therefore, the upper end of the workpiece 2, which is attached to the upper mold 5 and rising, is caught by the peeler 18, thereby preventing it from rising further. As a result, as the upper mold 5 rises further, the workpiece 2 separates from the upper mold 5 and is placed on the ejector 6. In this case, since the multiple peelers 18 are arranged at equal intervals in the circumferential direction of the workpiece 2, multiple portions of the workpiece 2 at its upper end are pulled down relative to the upper mold 5. Therefore, the workpiece 2 does not tilt and can be smoothly pulled out from the upper mold 5.

[0040] Simultaneously or subsequently, as workpiece 2 separates from upper mold 5, ejector 6 is lifted by rod 15 and begins to rise. This state is shown in... Figure 4D If the ejector 6 rises from the bottom dead center, the lowermost end 23a of the groove 23 moves to a position higher than where the sliding member 20 is located. Therefore, the sliding member 20 is gradually retracted by the inclined surface 23b formed at the lower end of the groove 23, and is eventually held in a position retracted from the outer peripheral surface of the ejector 6. Figure 4D As indicated by the arrow, the stripper 18 rotates in the same manner as the sliding member 20, thus operating in a position where it retracts radially outward from the through-part 8, i.e., from the area where the workpiece 2 moves vertically. In this state, the ejector 6 rises further, thus ejecting the workpiece 2 from the through-part 8 (lower form 4) and separating it from the lower form 4, thereby ending its processing without interfering with the stripper 18.

[0041] As described above, in the forging apparatus 1 of the present invention, the ejector 6 not only ejects the finished workpiece 2 from the lower mold 4, but also moves the stripper 18 to a position engaging with the workpiece 2 and a position not interfering with the workpiece 2 by moving up and down. That is, since the ejector 6 also functions as the driver of the stripper 18, there is no need to set a new dedicated drive mechanism on the stripper 18, which simplifies or miniaturizes the overall structure of the apparatus.

[0042] Furthermore, the present invention is not limited to the above-described embodiments. The peeler or sliding member may also be configured to move linearly back and forth in the radial direction of the workpiece or through-hole, instead of rotating around a predetermined axis in the vertical direction of the lower part and moving back and forth toward the workpiece or through-hole. Therefore, the shape of the peeler or sliding member can be a suitable shape other than rectangular or fan-shaped. Furthermore, the cam groove in the so-called cam mechanism used to move the peeler back and forth via the ejector may not be a groove that is long in the axial direction of the ejector, but may be a groove formed along the circumferential direction of the outer peripheral surface of the ejector.

[0043] Symbol Explanation

[0044] 1-Forging device, 2-Workpiece, 3-Hollow part, 4-Lower mold, 5-Upper mold, 6-Ejector, 7-Base part, 8-Through part, 9-Machined surface, 10-Plate component, 11-Die, 12-Divided type, 13-Sliding type, 14-Shaft part, 15-Rod, 16-Pointed type, 17-Holding plate, 18-Peeler, 19-Recess, 20-Sliding component, 21-Receiving part, 22-Connecting pin, 23-Groove, 23a-Lower end, 23b-Inclined surface, 24-Ejector plug, 25-Spring, 26-Mounting hole.

Claims

1. A forging apparatus, comprising: The upper and lower molds apply pressure to the workpiece to produce plastic deformation, thereby shaping it into a specified shape; A peeler engages with the workpiece, which is attached to the upper mold and rises, and pulls the workpiece down, thereby detaching the workpiece from the upper mold; and An ejector that lifts the workpiece from below, thereby disengaging the workpiece from the lower mold. The forging device is characterized in that... A sliding component, protruding and retracting in a direction orthogonal to the vertical movement direction of the ejector, is disposed inside the lower mold in the region where the ejector moves vertically. Furthermore, a cam surface is provided on the outer peripheral surface of the ejector to allow the sliding component to contact and move to a position retracting from the region and a position protruding into the region. The connecting component, which operates together with the sliding component, is disposed inside the lower part of the structure together with the sliding component. The stripper is configured to be mounted on the connecting member and to move via the connecting member to a position engaging with the workpiece and a retracted position separated from the workpiece.

2. The forging apparatus according to claim 1, characterized in that, The plurality of said peelers are arranged at equal intervals on the outer periphery of the workpiece on a circumference centered on the workpiece.

3. The forging apparatus according to claim 1 or 2, characterized in that, The cam surface has a lowermost end, and the portion extending upwards from the lowermost end becomes an inclined surface that recedes from the outer peripheral surface of the ejector toward the center side. The lowest end is formed on the outer peripheral surface of the ejector in such a way that it is located higher than the sliding member at the position where the workpiece is engaged with the stripper by the ejector.

4. The forging apparatus according to claim 1 or 2, characterized in that, The connecting component is composed of a rotating shaft component that is held inside the lower shape in the vertical direction and rotates about a central axis in the vertical direction. The sliding member is configured to be mounted on the lower end of the rotating shaft member, and by rotating together with the rotating shaft member, a portion of the front end protrudes into the region and then retracts. The peeler is configured to be mounted on the upper end of the rotating shaft component, and by rotating together with the rotating shaft component, a portion of the front end protrudes towards the position where it engages with the workpiece and then retracts.

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