JP3863959B2 - Press forming method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a press molding method and apparatus, and more particularly to a technique for improving molding accuracy such as roundness.
[0002]
[Background]
Relatively thick metal cylindrical parts such as steering lock mechanism lock holders are used in various other machines as well as automobile parts. As a method of manufacturing such cylindrical parts, a rectangular metal plate is pressed. It is considered to bend and round by the above. FIG. 14 is a diagram illustrating a manufacturing process when manufacturing the lock holder 10 as a cylindrical part. The lock holder 10 has a cylindrical shape, and a pair of slots 12 that are long in the axial direction are formed at two substantially symmetrical positions across the center line. The inner diameter of the lock holder 10 is about 19 mm, the outer diameter is about 27 mm, the wall thickness is about 4 mm, the axial length is about 38 mm, the axial length of the slot 12 is about 24 mm, and the circumferential width dimension is It is about 9 mm.
[0003]
In FIG. 14, the cutting step (a) is a step of preparing a rectangular metal plate material 14, and may be punched out from a strip or the like, for example, by shearing with a press. The thickness t of the metal plate 14 is substantially equal to the thickness of the lock holder 10, and the width dimension W in the rounding direction is substantially equal to the developed dimension at the thickness center of the lock holder 10. In the W-bending step (b), a pair of arc portions 18 having a semicircular arc shape having the same curvature as the target lock holder 10 are formed by bending the metal plate 14 using the press die 16 shown in FIG. It is formed into a substantially W-shaped corrugated sheet component 20 having it. In the step (c), a slot 12 is formed in each of the pair of arc portions 18 of the corrugated sheet component 20 using a press die 22 shown in FIG. In the primary O bending process of (d), the corrugated sheet component 20 is bent using a press die 24 shown in FIG. 17, thereby forming a pre-rounded product 28 rounded into a substantially cylindrical shape. In the preliminary rounded product 28, the end edge 26 in the rounding direction is opened by a predetermined dimension, and the slot 12 is formed at two positions spaced from the end edge 26 in the circumferential direction by approximately 90 °.
[0004]
In the final secondary O bending step (e), the preliminarily rounded product 28 is formed into the intended lock holder 10 using a press die 30 shown in FIG. The press die 30 includes a pair of upper and lower upper dies 32 and 34 and a metal core 36. The upper die 32 and the lower die 34 are formed in a semicircular arc shape having a curvature substantially equal to the outer diameter of the lock holder 10. While the surface is formed, the cored bar 36 has a cylindrical shape having an outer diameter substantially equal to the inner diameter of the lock holder 10 and is movable in the vertical direction in a substantially horizontal posture. The pre-rounded product 28 is attached (hanged) to the cored bar 36 with the opening of the edge 26 facing upward, for example, and the upper die 32 is lowered in this state, whereby the molding surface of the lower die 34 is formed. While being pushed in, it is clamped between the upper die 32 and the lower die 34 and rounded.
[0005]
[Problems to be solved by the invention]
By the way, in the secondary O bending step (e), the edges 26 are abutted with each other, but since there are a pair of slots 12 on both the left and right sides, the upper and lower molds 32 and 34 are viewed from above and below. When pinched, there is a risk of buckling at the portion where the slot 12 is formed (the connecting portions on both sides in the axial direction). When such buckling occurs, a sufficient butt load cannot be obtained, so that the dimensional accuracy and roundness of the inner and outer diameters decrease.
[0006]
Further, in the secondary O bending step (e), when the upper mold 32 and the lower mold 34 are clamped from above and below, the lock holder 10 is hardly subjected to molding pressure from the left and right directions. Can not be formed easily, and the dimensional accuracy and roundness of inner and outer diameters are reduced.
[0007]
Further, a portion 38 opposite to the butted portion of the edge 26 across the axis is formed into a convex shape in the (b) W bending process, and the lower die 34 is formed in the secondary O bending process (e). Since it is bent in the opposite direction when it is pushed into the surface, as shown in FIG. 19, a protrusion is formed that protrudes outward (downward) in the completed state. Further, when the pre-rounded product 28 is pushed into the molding surface of the lower die 34, the burr 12a as shown in FIG. It may become.
[0008]
The present invention has been made in the background as described above. The purpose of the present invention is to provide a secondary O bending process for obtaining a cylindrical part from a pre-rounded product in which a metal plate is previously rounded into a substantially cylindrical shape. In this case, buckling occurs in the slot part (joint part on both sides in the axial direction) formed in the pre-rounded product, or a convex protrusion is generated in the part opposite to the butted part of the edge of the pre-rounded product. Thus, it is intended to prevent the dimensional accuracy and roundness of the inner and outer diameters from being lowered, and the occurrence of burrs in the slot, resulting in a functional problem due to a narrow groove width.
[0009]
[Means for Solving the Problems]
  In order to achieve the above object, the first invention is as follows. (A) A metal plate is rounded into a substantially cylindrical shape in advance.In addition, the edge in the rounding direction is open, and long slots in the axial direction are provided at two positions spaced apart in the circumferential direction by 90 ° from the edge.For pre-rounded products,Press workThe edges in the rounding directionA press molding method for obtaining a target cylindrical part, wherein (b) a mounting step of mounting the pre-rounded product on a cylindrical cored bar having an outer diameter substantially equal to the inner diameter of the cylindrical part; and (c) the cylinder Curvature approximately equal to the outer diameter of the partOf partial cylindrical shape each having 1/3 circumference3 including a movable die having a molding surface and integrally disposed on the press slide.SuddenlyEach of the press dies arranged separately is brought close to the core metal, and the preliminary round product in a posture in which the edge in the rounding direction is located on the movable mold side is placed between the core metal and the press die. And a pressing step for press working.
[0011]
  First2The invention includes (a) rounding a metal plate into a substantially cylindrical shape in advance.In addition, the edge in the rounding direction is open, and long slots in the axial direction are provided at two positions spaced apart in the circumferential direction by 90 ° from the edge.For pre-rounded products,Press workThe edges in the rounding directionA press molding apparatus for obtaining a target cylindrical part, wherein (b) a cylindrical shape having an outer diameter substantially equal to the inner diameter of the cylindrical part is disposed substantially horizontally,In a posture where the edge in the rounding direction is upwardA core metal to which the pre-rounded product is mounted, and (c) a curvature substantially equal to the outer diameter of the cylindrical part.Of partial cylindrical shape each having 1/3 circumferenceIt has a molding surface and 3Suddenly3 divided and arranged so as to be able to approach and separate from the core metalHornA press die, and (d) interlocking means for mechanically interlocking the press die so as to approach the cored bar and pressing the pre-rounded product between the cored bar and the press die. And (e) the press die is integrally disposed on a press slide located above the core metal and is reciprocated in a straight line direction perpendicular to the axis of the core metal and at the lower end. The movable mold in which the molding surface is formed, and arranged so as to be movable in two symmetrical directions across the straight line and across the straight line in a plane perpendicular to the axis of the core. It has a pair of gathering dies each having the molding surface formed inside the straight line.
[0012]
  First3Invention2In the press molding apparatus of the invention,(a) The cored bar is disposed so as to be movable in the straight line direction, and when the movable die is moved to a processing position for pressing the preliminary rounded product, the movable die is engaged with the preliminary rounded product. While being moved toward the machining position together with the movable mold, (b)The interlocking means includes an urging means that always holds the pair of close-up dies at a standby position that is separated from the straight line;AdditionWhen moved to the work position,The pre-rounded product moved toward the processing position together with the cored bar by the movable dieThe pair of collapsible moldsMolding surface andIt is characterized by comprising a cam mechanism that causes the pair of close-up types to approach the straight line against the urging force of the urging means by being engaged.
[0016]
【The invention's effect】
  According to the press molding method of the first invention, in the pressing step, the curvature is substantially equal to the outer diameter of the cylindrical part.Of partial cylindrical shape each having 1/3 circumference3 with a molding surface around the mandrelSuddenlyIn order to press the pre-rounded product between the core bar and the press die, the upper die and the lower die are moved up and down as before. Compared to the case of pressing in the direction, the pre-rounded product is pressed with a uniform pressing force around the axis, and the dimensional accuracy and roundness of the inner and outer diameters are improved.That is, the grooveBuckling is less likely to occur at the part where the hole is formed (the connecting part on both sides in the axial direction), and a sufficient butt load can be obtained when matching the edge of the pre-rounded product, and the axis of the pre-rounded product is sandwiched As a result, convex protrusions are less likely to occur on the opposite side of the end edge but the dimensional accuracy and roundness of the inner and outer diameters are improved. Further, since the pre-rounded product is not forcibly pushed into the lower mold as in the case of pressing in the vertical direction, there is no inconvenience that burrs are hardly generated in the groove hole, and the groove width becomes narrow and causes a functional problem.
[0017]
  Of the second inventionThe press molding apparatus substantially includes the firstWith lightThe same effect can be obtained, but this press forming apparatus is 3HornSince the press dies are mechanically interlocked, complicated control is not necessary as compared with the case where they are driven independently.HornThe press die can be brought close to the cored bar.
[0018]
  Also, The press mold is a movable mold and a pair ofHaveConfigured, andBy interlocking meansSince it is interlocked, the apparatus can be configured easily and inexpensively while ensuring the strength required for press working.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
  Here, the present inventionThe circleIt is suitable for press processing of cylindrical parts with end edges facing each other and having slots, such as a lock holder of a steering lock mechanism.TheFor example, it is suitable for pressing a cylindrical part having a relatively thick wall of about 3 mm or more and a diameter of about 20 to 65 mm.
[0022]
  First3In the invention, the interlocking means is provided with the cam mechanism, but the interlocking means can be configured using a link mechanism instead of the cam mechanism.
[0023]
  First2In carrying out the invention, the cored bar can be fixedly disposed at a predetermined fixed processing position, but it can be moved in a direction perpendicular to the axis to absorb a dimensional error. For example, it is disposed so as to be movable in the same linear direction as that of the movable type, and is always held at a standby position separated from the processing position by the urging means, and is moved to the processing position by the moving type during press processing. It is desirable to do so. In addition, a kicker pin that can be reciprocated in a direction parallel to the axis of the core bar is provided at the standby position so that the pressed cylindrical part mounted on the core bar is automatically paid out by the kicker pin. It is also possible to do.
[0024]
  FirstMysteriousIn carrying out,ThreeThe press dies do not necessarily need to be mechanically interlocked, and may be driven by separate driving means such as a hydraulic cylinder.
[0026]
  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following embodiments, a description will be given of a press forming apparatus 40 that can suitably perform the (e) secondary O bending step in FIG. 14 when the lock holder 10 is manufactured. 1 is a plan view excluding an upper die (movable die 60) and the like of the press forming apparatus 40, FIG. 2 is a front view, FIG. 3 is a right side view, FIG. 4 is a sectional view taken along line IV-IV in FIG. 1 is a cross-sectional view taken along the line V-V in FIG. 1, and FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. As shown in FIG. 3, the press forming apparatus 40 is integrally fixed substantially horizontally on a bed 41 of a press machine. On the lower mold base 42, a V-shaped pedestal 44 having a V-shaped groove on the upper surface is disposed. On the V-shaped pedestal 44, a pair of close-up molds 46 and 48 are disposed. As shown in an enlarged view in FIG. 9, the V-shaped groove has side walls 44a and 44b on both sides that are cored.64The dies 46 and 48 are inclined obliquely upward and downward with the inclined surfaces 46a and 48a being in sliding contact with the side walls 44a and 44b. Translated. Formed at the upper corners of the inner sides of the collecting dies 46, 48 are partially cylindrical molding surfaces 46b, 48b each having a curvature substantially equal to the outer diameter of the lock holder 10 and having a circumference of about 1/3. By making the inner side (slanting downward) approach along the side walls 44a and 44b to a processing position where the two are in close contact with each other, the centers of curvature of the molding surfaces 46b and 48b are substantially coincided with each other, and the cylinder has a circumference of about 2/3. A surface is formed.
[0027]
A spring 50 is provided between the gathering dies 46 and 48 and at each bottom, and the gathering dies 46 and 48 are urged in a direction away from each other along the V-shaped groove of the V-shaped pedestal 44. Yes. A pair of upper stoppers 52 are provided on the upper surface of the V-shaped pedestal 44, and define an upward moving end of the dies 46 and 48 by the urging force of the spring 50, that is, a standby position. Further, as shown in FIG. 1 or FIG. 2, a front guide plate 54 and a rear guide plate 56 are installed in front of the V-shaped pedestal 44 (right side in the figure) and rearward (left side in the figure), respectively. The molds 46 and 48 are prevented from shifting in the front-rear direction. FIG. 9 shows a state in which the front guide plate 54 is removed.
[0028]
  Above the lower mold base 42, an upper mold base 58 is disposed so as to be movable in the vertical direction via a pair of guide members 63. The upper mold base 58 is integrally fixed to a press slide 59 of a press machine, and is reciprocated in the vertical direction by driving means 61 (see FIG. 3) including an electric motor and a crank mechanism or a hydraulic cylinder. A movable die 60 is disposed on the lower surface. The movable mold 60 is provided directly above the pair of the collapsing molds 46 and 48 and is reciprocated in the vertical direction which is a straight line direction together with the upper mold base 58, while the lower end of the movable mold 60 is attached to the lock holder 10. A partially cylindrical molding surface 60a having a curvature substantially equal to the outer diameter of the cylindrical member and having a circumference of about 1/3 is formed. By being lowered to the processing position of the lower end, a pair of offsets are formed as shown in FIG. The centers of curvature of the molding surfaces 46b and 48b of the molds 46 and 48 and the molding surface 60a are substantially matched to form a substantially perfect cylindrical surface. These movable mold 60 and the pair of gathering molds 46 and 48 are 3SuddenlyIt corresponds to a press die arranged in a divided manner. The front guide plate 54 has a U-shaped cutout 54a as shown in FIG.
[0029]
On the other hand, as shown in FIG. 9, in a state where the movable die 60 is raised to the original position of the rising end, it is directly below the moving die 60, that is, on a straight line on which the movable die 60 is moved, and is processed at the lower end. A cored bar 64 is disposed at an intermediate position between the position and a position perpendicular to the straight line, specifically, a position perpendicular to the plane of FIG. 9 (the front-rear direction of the apparatus). The cored bar 64 has a cylindrical shape with an outer diameter substantially equal to the inner diameter of the lock holder 10, and a tapered surface is formed to be tapered at the tip, so that the pre-rounded product 28 can be easily mounted. It is like that.
[0030]
2 and 4, the cored bar 64 is connected to a cored bar slide base 66, and the cored bar slide base 66 is fitted into a guide 70 having a U-shaped groove so that the U-shaped. It is arranged so as to be slidable in the vertical direction along the groove. In the guide 70, a spring 68 is disposed as a biasing means at the bottom of the cored bar slide base 66, and the cored bar slide base 66 is always biased upward by the spring 68 to move the cored bar 64 of FIG. While being held at a standby position indicated by a two-dot chain line (solid line in FIG. 9), during the press molding in which the movable die 60 is lowered, it is allowed to descend to the machining position shown in FIGS. A lid member 72 is disposed on the upper surface of the guide 70 to prevent the core bar slide base 66 from protruding upward. FIG. 1 shows a state where the lid member 72 is removed.
[0031]
When the movable die 60 is lowered from the original position shown in FIG. 9, the molding surface 60 a is first brought into contact with the pre-rounded product 28 attached to the core metal 64, and thereafter the core metal 64 is moved to the movable die 60. At the same time, it is lowered against the biasing force of the spring 68. When the lower end of the pre-rounded product 28 is brought into contact with the molding surfaces 46b and 48b of the pair of gathering dies 46 and 48 as shown in FIG. 10, the gathering dies 46 and 48 thereafter become V-shaped grooves. Are lowered against the urging force of the spring 50 along the side walls 44a and 44b, and are brought close to the machining position shown in FIG. The V-shaped pedestal 44 and the inclined surfaces 46a and 48a of the collapsing dies 46 and 48 in which the V-shaped grooves are formed correspond to cam mechanisms, and the spring 50 corresponds to urging means. The interlocking means is constituted by the cam mechanism and the biasing means.
[0032]
As shown in FIG. 4, a presser pin 62 is disposed on the upper mold base 58 above the metal core slide base 66. When the movable die 60 comes into contact with the preliminary rounded product 28, the presser pin 62 is adjusted so as to have a slight gap in the vertical direction (gap smaller than the thickness of the preliminary rounded product 28) with the mandrel slide base 66. Therefore, even when the blanking is performed without attaching the pre-rounded product 28, the presser pin 62 is fixed to the cored bar slide base 66 and the cored bar slide base 66 before the movable die 60 comes into contact with the cored bar 64. In order to push down the cored bar 64, the movable die 60 does not directly hit the cored bar 64. Further, when the shading of the cored bar slide base 66 is more than a slight gap between the presser pin 62 and the cored bar slide base 66, it is difficult to cause the twisting.
[0033]
As shown in FIGS. 1 and 2, the payout mechanism for taking out the lock holder 10 press-formed from the pre-rounded product 28 from the press-forming device 40 is an air cylinder 78 disposed in the front-rear direction at a rear position of the guide 70. And a pair of kicker pins 74 connected to the output rod of the air cylinder 78 via a connecting block 76. The connecting block 76 is slidable on the slide base 80 in the front-rear direction, and the kicker pins 74 are arranged on the left and right sides of the core metal 64 in a state where the core metal 64 is held at the standby position. They are arranged so as to be close and parallel to each other.
[0034]
The kicker pin 74 passes through the guide 70, the core metal slide base 66, and the rear guide plate 56. Specifically, as shown in FIGS. 4 to 6, the guide 70 is provided with a through hole that is slightly larger than the cross section of the kicker pin 74, and the mandrel slide base 66 is allowed to move in the vertical direction. Therefore, an oval through hole having a length substantially equal to the moving distance of the cored bar slide base 66 is provided, and the rear guide plate 56 is provided with a through hole having substantially the same size as the guide 70. The pins 74 can be moved in the front-rear direction through the through holes. 7 and 8 is connected to the air cylinder 78, and a trapezoidal dog 84 provided on the upper mold base 58 and a piece roller 86 are engaged with each other. As a result, the air circuit is temporarily switched only when the upper mold base 58 is moved from the descending end to the ascending end, and the output rod and the kicker pin 74 are temporarily projected forward.
[0035]
Next, the operation of the press molding apparatus 40 will be described in order. First, as shown in FIG. 9, in the state where the movable die 60 is held in the original position, the tip side of the core metal 64, that is, the front side of the device, by the work automatic supply device (not shown) or the operator's manual work. Then, the pre-rounded product 28 is mounted on the cored bar 64. For example, as shown in FIG. 9, the pre-rounded product 28 is hooked on the cored bar 64 in such a posture that the opening of the end edge 26 faces upward. This corresponds to the mounting step described in claim 1. In this state, when the movable die 60 is lowered together with the upper die base 58, the movable die 60 is brought into contact with the pre-rounded product 28 attached to the cored bar 64. Next, as the movable die 60 is lowered, the core metal 64 holding the pre-rounded product 28 and the core metal slide base 66 to which the core metal 64 is fixed are moved downward against the biasing force of the spring 68. Pushed down. Next, when the movable die 60 is further lowered, the pre-rounded product 28 pushes down the gathering dies 46 and 48 downward, along the V-shaped groove of the V-shaped base 44 against the biasing force of the spring 50. The gathering dies 46 and 48 are slid down and brought close to each other, and the pre-rounded product 28 is pressed from three sides by the movable die 60 and the gathering dies 46 and 48 to form the lock holder 10. Thus, the step of pressing the pre-rounded product 28 with the cored bar 64 by the movable die 60 and the pair of closing dies 46 and 48 corresponds to the pressing step according to claim 1.
[0036]
After forming the lock holder 10, the upper mold base 58 is raised by the reverse operation, and the mechanical valve 82 is temporarily switched by the dog 84 near the raised end, whereby the kicker pin 74 is advanced by the air cylinder 78. The lock holder 10 is paid out from the cored bar 64 by the kicker pin 74. Subsequently, when the mechanical valve 82 is returned to the normal position by the biasing force of the spring, the kicker pin 74 is moved backward by the reverse operation to the forward movement, and is returned to the normal position.
[0037]
As described above, according to the press molding apparatus 40 of the present embodiment, the movable die 60 and the close-up dies 46 and 48 disposed around the cored bar 64 are brought close to the cored bar 64, respectively. Since the preliminarily rounded product 28 is pressed between the movable die 60 and the gathering dies 46 and 48, the preliminarily rounded product 28 is used as compared with the conventional case where the upper die and the lower die are clamped in the vertical direction. Is pressed with a uniform pressing force around the axis, and buckling is less likely to occur at the portion where the slot 12 is formed (the connecting portions on both sides in the axial direction), and the edge 26 of the pre-rounded product 28. A sufficient butting load can be obtained when butting is not performed, and convex protrusions are less likely to occur at a portion 38 opposite to the butting portion of the edge 26 across the axis of the pre-rounded product 28, and the inner and outer diameter dimensions are reduced. Accuracy and roundness can be improved. Moreover, since the pre-rounded product 28 is not forcedly pushed into the lower mold as in the case of clamping in the vertical direction, there is a problem that burrs are not easily generated in the slot 12, and the groove width becomes narrow and this causes a functional problem. Absent. For example, the roundness is about φ1 to about φ0.1 to 0.05, the burr height is about 0.7 mm to about 0.2 mm, and the inner diameter tolerance range is about 0.2.
[0038]
On the other hand, in the press molding apparatus 40 of the present embodiment, the movable die 60 and the pair of gathering dies 46, 48 constitute a press die, and the gathering dies 46, 48 function as a cam mechanism. Since it is interlocked with the movable die 60 by the action of the spring 50, complicated control is unnecessary as compared with the case where they are driven independently, and the movable die 60 and the gathering dies 46, 48 are always at an appropriate constant timing. Is brought close to the cored bar 64. In addition, the apparatus can be configured easily and inexpensively while ensuring the strength necessary for press working.
[0039]
In the above embodiment, the pair of dies 46 and 48 are interlocked with the movable die 60 via the cored bar 64 and the pre-rounded product 28. However, as shown in FIGS. The mold 90 and the pair of gathering molds 92 and 94 can be directly engaged and interlocked. That is, the movable mold 90 is formed with a pair of inclined surfaces 90a, 90b that expands downward as opposed to the vertical direction, while the close-up molds 92, 94 are inclined inward as they move upward. The inclined surfaces 92a and 94a are formed symmetrically with respect to the vertical direction, and a pair of the closing dies 92 and 94 are brought together with the lowering of the movable die 90 by the engagement between the inclined surfaces 90a and 92a and 90b and 94a. Is approaching inward. 90c, 92b and 94b are molding surfaces corresponding to the molding surfaces 60a, 46b and 48b. The close-up dies 92 and 94 are accommodated in an accommodation hole 96a of a pedestal 96 fixed on the lower die base 42, and can be moved closer to and away from each other by a predetermined dimension. By this, it is held at the standby position which is the moving end on both sides. The inclined surfaces 90a, 90b and 92a, 94a correspond to cam mechanisms, and the spring 98 corresponds to urging means. These cam mechanisms and urging means constitute interlocking means.
[0040]
As mentioned above, although the Example of this invention was described in detail based on drawing, this invention can be applied also in another aspect.
[0042]
  For exampleThe moving direction of the gathering dies 46, 48, 92, 94 can be changed as appropriate. For example, in the case of the gathering dies 92, 94, they can be configured to rise as they approach the inside. .
[0043]
Further, the processing step of FIG. 14 is merely an example, and may be changed as appropriate, for example, the step of punching (c) may be performed before the step of bending W of (b).
[0044]
In the above-described embodiment, the trapezoidal dog 84 provided on the upper mold base 58 is engaged with the scraping roller 86, so that the mechanical valve 82 is temporarily switched to drive the air cylinder 78. However, an electric signal is taken out by a rotary cam switch provided on a crankshaft of a crank mechanism constituting the driving means 61, and an electromagnetic valve is temporarily switched to drive the air cylinder 78. You can also.
[0045]
The present invention can be modified in various other ways without departing from the gist thereof.
[Brief description of the drawings]
FIG. 1 is a plan view excluding an upper die and the like of a press molding apparatus to which the present invention is applied.
FIG. 2 is a front view of the press molding apparatus of FIG.
FIG. 3 is a right side view of the press molding apparatus of FIG. 1;
4 is a sectional view taken along the line IV-IV of the press molding apparatus of FIG.
5 is a VV cross-sectional view of the press molding apparatus of FIG. 1;
6 is a VI-VI cross-sectional view of the press molding apparatus of FIG. 1. FIG.
7 is a diagram for explaining the operation of a mechanical valve of the press molding apparatus of FIG. 1; FIG.
8 is a diagram illustrating an air circuit including a mechanical valve of the press molding apparatus of FIG. 1. FIG.
FIG. 9 is a view for explaining three press dies of the press molding apparatus of FIG. 1;
FIG. 10 is a view showing a state in which the movable die is lowered in FIG. 9 and is engaged with a pair of close-up dies through a core metal and a pre-rounded product.
FIG. 11 is a diagram for explaining a main part of another embodiment of the present invention, which corresponds to FIG. 9;
FIG. 12 is a view showing a state in which the movable die is lowered in FIG. 11 and engaged with a pair of close-up dies via a cored bar and a pre-rounded product.
FIG. 13 is a view showing a state in which a press working is performed on a pre-rounded product together with a closing die that is lowered to a processing position at a descending end and is moved closer together.
FIG. 14 is a diagram illustrating a manufacturing process for manufacturing a lock holder as a cylindrical part.
FIG. 15 is a diagram illustrating the W bending process of FIG. 14 (b).
FIG. 16 is a diagram for explaining the hole punching process of FIG.
FIG. 17 is a diagram for explaining a primary O bending process of FIG.
FIG. 18 is a diagram for explaining the secondary O bending step of FIG. 14 (e).
19 is a view for explaining a burr generated in a slot when a lock holder is manufactured by the secondary O bending process of FIG. 18 and a convex protrusion generated at a portion on the opposite side of the butted portion of the edge. .
[Explanation of symbols]
10: Lock holder (cylindrical part)
12: Slot
14: Metal plate
26: Edge
28: Preliminary rounded product
40: Press molding device
44: V-shaped base (cam mechanism, interlocking means)
46, 48, 92, 94: Alignment type (press type)
50, 98: Spring (biasing means, interlocking means)
59: Press slide
60, 90: moving type (press type)
64: Core
90a, 90b, 92a, 94a: inclined surface (cam mechanism)

Claims (3)

A metal plate is rounded into a substantially cylindrical shape in advance , and the edge in the rounding direction is open, and long slots in the axial direction are provided at two positions spaced from the edge in the 90 ° circumferential direction. the preliminary rounding products, a press molding method to obtain a cylindrical component of interest by abutting together the edges of the round grain direction by performing press working,
A mounting step of mounting the pre-rounded product on a cylindrical cored bar having an outer diameter substantially equal to the inner diameter of the cylindrical part;
3 having a partially cylindrical molding surface having a curvature substantially equal to the outer diameter of the cylindrical part and having a circumference of 1/3, respectively, and including a movable die integrally disposed on the press slide. The pre-rounded product in a posture in which the press dies divided into two are respectively brought close to the core bar and the edge in the rounding direction is located on the movable mold side is the core metal and the press die. And a pressing step of press-working between them. A metal plate is rounded into a substantially cylindrical shape in advance , and the edge in the rounding direction is open, and long slots in the axial direction are provided at two positions spaced from the edge in the 90 ° circumferential direction. the preliminary rounding products, a press forming apparatus for obtaining a cylindrical component of interest by abutting together the edges of the round grain direction by performing press working,
A cored bar having a cylindrical shape with an outer diameter substantially equal to the inner diameter of the cylindrical part, arranged substantially horizontally, and mounted with the preliminary rounded product in an orientation in which an edge in the rounding direction is upward ;
Has a shaped surface of the partially cylindrical shape with respective 1/3 circumference at substantially equal curvature to the outer diameter of the cylindrical part, accessible and away from the core metal is divided into three around the core metal and three press die disposed,
Interlocking means for mechanically interlocking the press die to approach the cored bar, and pressing the pre-rounded product between the cored bar and the press die, and
The press die is integrally disposed on a press slide located above the core metal, and is reciprocated in a straight line direction perpendicular to the axis of the core metal, and the molding surface is formed at the lower end. The movable type is arranged so as to be movable in two symmetrical directions across the straight line and in a plane perpendicular to the axis of the cored bar, and on the inner side near the straight line. Each of the press forming apparatuses includes a pair of gathering dies each having the forming surface formed thereon. The cored bar is disposed so as to be movable in the straight line direction, and the movable die is engaged with the preliminary rounded product when the movable die is moved to a processing position for pressing the preliminary rounded product. While being moved toward the processing position together with the movable mold,
The interlocking means includes a biasing means always the pair of Asked type held in a standby position away from the straight line, when the mobile is moved to the front Symbol machining position, the core by the mobile The preliminary rounded product moved together with the gold toward the machining position is engaged with the molding surfaces of the pair of gathering molds, so that the pair of gathering molds are respectively resisted against the biasing force of the biasing means. The press forming apparatus according to claim 2 , comprising a cam mechanism that approaches the straight line.

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