JPH08132158A - Method and device for production of hollow cylindrical part - Google Patents

Abstract

PURPOSE: To provide the method and device to form a hollow cylindrical part in high precision. CONSTITUTION: A sink 11 is formed to the corner of inner surface by applying reverse ironing to a cylindrical part 5 of a cap shaped stock 4, as this is made to starting point of breaking, a bottom part 6 is sheared/separated from the cylindrical part 5 and a hollow cylindrical part 10 is obtained. That is, compression force in the axial direction is applied to a cylindrical part 5 of a cap shaped stock 4 and the outward bulging part in radial direction, which is formed in the neighborhood of bottom part, is sheared/cut by a die 23 and outer punch 22 and a hollow cylindrical part 10 is produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a hollow cylindrical part with high precision and without machining, and an apparatus used therefor.

[0002]

2. Description of the Related Art Conventionally, the following methods are known as methods for manufacturing hollow cylindrical parts without machining. A method of punching out the bottom of a component 50 obtained by press-molding a plate material into a cup shape (FIG. 18). A method of shearing the bottom part of the part 60 obtained by press-molding a plate material into a cup shape from the cylindrical part (FIG. 19).

[0003]

However, in the above method of punching out the bottom of the cup, the fracture surface 51 shown in FIG. 18 remains convex toward the inner side in the radial direction, and the inner diameter accuracy of the hollow cylindrical part is improved. Needs to cut the convex portion. In addition, the outer surface 52 of the cup R portion is in a lacking state. Moreover, in the method of shear-cutting the cup bottom portion in the diametrical direction, sagging 61 and burrs 62 are generated on the cut surface. Further, shearing force is applied to the cylindrical portion in the radial direction, and the cylindrical portion is crushed into an elliptical shape, which deteriorates the diameter accuracy. An object of the present invention is to provide a method and an apparatus for manufacturing a hollow cylindrical part with high accuracy and without machining (cutting).

[0004]

The present invention which achieves the above object is as follows. (1) A cup-shaped material having a bottom portion and a cylindrical portion is formed from a flat plate-shaped metal material, and the cylindrical portion of the cup-shaped material is squeezed toward the bottom portion to squeeze meat into the cylindrical portion rather than the outer surface of the bottom portion. Escape in the opposite direction to form a sink mark on the inner surface corner of the cup-shaped material, and form a protrusion protruding from the bottom outer surface in the opposite direction to the cylindrical portion, at the same time as or after the ironing, A method of manufacturing a hollow cylindrical component, comprising a step of applying a shearing force between the bottom portion of the cup-shaped material and the cylindrical portion, and cutting and separating the bottom portion from the cylindrical portion at the sink mark portion. (2) The die is provided with a guide portion extending from the ironing portion to the outer punch side, and when the protrusion is formed in the ironing, the guide portion guides the protrusion so that the meat flows in the axial direction ( 1) The method for producing a hollow cylindrical component as described above. (3) A stepped surface is provided on the outer punch that is pressed against the bottom of the cup-shaped material, and a guide portion that extends from the ironing portion to the outer punch is formed on the die. In the step (1), the tip corner portion of the protrusion is regulated by the guide portion of the die, the step surface of the outer punch, and the outer peripheral surface of the tip portion from the step surface of the outer punch to be a substantially right angle portion (1 ) The method for producing a hollow cylindrical component as described above. (4) Cutting of the bottom part from the cylindrical part is formed by forming a protrusion protruding in the direction in which the bottom part of the cup-shaped material is pushed into at least one of the inner punch and the outer punch that are pressed against the bottom part of the cup-shaped material. The method for producing a hollow cylindrical component according to (1), wherein the condition for shearing force generation is controlled by the protrusion in the separation step. (5) A cup-shaped material having a bottom portion and a cylindrical portion is formed from a flat metal material, and the cup-shaped material is attached to the cylindrical portion of the cup-shaped material with the entire bottom surface of the cup-shaped material being in contact with the outer punch. A compressive force is applied in the direction of the bottom portion of the cylindrical portion to buckle and bend a portion of the cylindrical portion in the vicinity of the bottom portion outward in the radial direction to form a radially outward bulged portion, and then the cylindrical portion of the cup-shaped material. 2. A method for manufacturing a hollow cylindrical component, comprising the step of shearing the radially outwardly bulged portion with a die and the outer punch. (6) An apparatus used for manufacturing a hollow cylindrical component from a cup-shaped material having a bottom portion and a cylindrical portion, the hollow cylindrical component having a tip end surface pressed against an inner surface of the bottom portion of the cup-shaped material. An inner punch having an outer diameter approximately equal to the inner diameter of the cup-shaped material, a tip surface that is pressed against the outer surface of the bottom of the cup-shaped material, and a step surface in the middle of the axial direction,
An outer punch having an outer diameter at the tip of the step surface substantially equal to the inner diameter of the hollow cylindrical component and an outer diameter at the rear of the step surface substantially equal to the outer diameter of the hollow cylindrical component; and an outer punch of the hollow cylindrical component. An apparatus for manufacturing a hollow cylindrical part, comprising: a die having an ironing portion having an inner diameter substantially equal to the diameter. (7) The die extends axially from the ironing portion to the outer punch side and has an inner diameter larger than the inner diameter of the ironing portion to prevent the meat squeezed by the ironing portion from flowing outward in the radial direction. It has a guide part (6)
An apparatus for manufacturing the hollow cylindrical part described. (8) The apparatus for manufacturing a hollow cylindrical component according to (6), wherein the stepped surface of the outer punch and the outer peripheral surface of the tip portion from the stepped surface are orthogonal to each other. (9) The hollow cylinder according to (6), wherein at least one of the inner punch and the outer punch has a projection protruding in a direction in which the bottom portion of the cup-shaped material is pushed into a position corresponding to an inner diameter of the hollow cylindrical component. Parts manufacturing equipment. (10) An apparatus used for producing a hollow cylindrical component from a cup-shaped material having a bottom portion and a cylindrical portion,
An inner punch having an end surface pressed against the inner surface of the bottom of the cup-shaped material and having an outer diameter substantially equal to the inner diameter of the hollow cylindrical component, and a tip surface pressed against the entire bottom surface of the cup-shaped material. An outer punch having an outer diameter substantially equal to the outer diameter of the hollow cylindrical part, and an ironing portion having an inner diameter substantially equal to the outer diameter of the outer punch, and the outer punch side of the iron punch is radially outside the cup-shaped material. An apparatus for manufacturing a hollow cylindrical part, comprising: a die that escapes radially outward so as to allow a buckling deformation in one direction.

[0005]

In the method (1) and the apparatus (6), the meat squeezed and squeezed from the cylindrical portion of the cup-shaped material to the bottom is released in the direction opposite to the cylindrical portion. At the inner corner, there is a sink mark with the tip facing diagonally outward, and this sink mark is the starting point (notch) of fracture during shear separation.
As a result, the bottom portion can be easily punched out, and the fracture surface can be a surface that does not project to the inner peripheral surface of the cylindrical portion. The diameter accuracy of the hollow cylindrical part is obtained by ironing, and the fractured surface punched out at the bottom does not project to the inner diameter side, so it can be used as it is without cutting. In the method (2) and the apparatus (7), the die is provided with a guide portion extending from the ironing portion to the outer punch side so that the meat of the cup-shaped material does not flow radially outward during ironing. Since it is regulated to, the protruding portion smoothly forms one end portion of the hollow cylindrical component. Then, by squeezing the protruding portion with the ironing portion of the die, the inner and outer diameters of the protruding portion are accurately produced by the die and the outer punch. In the method of (3) and the apparatus of (8), since the step and the outer punch side surface of the tip portion are orthogonal to the step surface, and the die inner surface and the outer punch side surface are parallel, the projecting portion has the step and step surfaces. When the space between the outer punch side surface of the tip and the inner surface of the die is filled up, the corners of the hollow cylindrical part on the protruding side, inside and outside the tip, are angled at right angles, and become corners without sagging or burr. . In the method of (4) and the device of (9), since the projection is formed on the peripheral edge of at least one of the inner punch and the outer punch, the shearing force from the punch is concentrated and is applied to the seat portion of the cup-shaped material to impart the shearing force. You can control the conditions. The method of the above (5) and the above (1
In the device of 0), a compressive force is applied to the cylindrical portion to cause the portion near the seat portion of the cylindrical portion to buckle and bend so as to bulge outward in the radial direction,
This portion is cut off by shearing between the die and the outer punch to separate the cylindrical portion and the bottom portion, and the bottom portion serves as a lid for the cylindrical portion. Since the lid and the cylindrical part are processed by the ironing part of the same die, they have the same diameter and high accuracy. Further, due to the compressive force in the axial direction, the corners of the cylindrical portion become right angles.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. 1 is applicable to all the embodiments of the present invention, FIGS. 2 to 4 show a method and apparatus according to the first embodiment of the present invention, and FIGS. 5 to 7 show a second embodiment of the present invention. FIG. 5, FIG. 6, FIG. 8 (FIGS. 5 and 6 are second and third examples).
(Common to the embodiments) shows a method and an apparatus according to the third embodiment of the present invention, and FIGS. 9 to 12 show a method and an apparatus according to the fourth embodiment of the present invention, and FIGS. 14 shows the method and apparatus according to the fifth embodiment of the present invention, and FIG.
17 to 17 show a method and apparatus according to the sixth embodiment of the present invention. Components common to all the embodiments are given the same reference numerals in all the embodiments.

First, the parts common to all the embodiments of the present invention will be described with reference to FIG. The method of the present invention is illustrated in FIG.
As shown in FIG. Step 1: Material punching (a in FIG. 1) Step 2: Drawing (b in FIG. 1) Step 3: Ironing (c in FIG. 1) Step 4: Ironing 2 + trim (d in FIG. 1) Step 5: Coining (FIG. 1) E) Step 6: Reverse ironing (f in FIG. 1) Step 7: Punch bottom trim (g in FIG. 1) Step 8: Ironing 3 (h in FIG. 1)

In step 1, the metal flat plate 1 is punched into a circular shape. In step 2, the flat plate 1 is drawn (with almost no change in plate thickness) to form a shallow cup-shaped material 2. In step 3, the cup-shaped material 2 is ironed (with a change in the plate thickness of the cylindrical portion) to form a deep cup-shaped material 3. In step 4, ironing is further performed and trimming is performed to obtain a deeper cup-shaped material 4. The cup-shaped material 4 has a cylindrical portion 5 and a bottom portion 6. In step 5, a coining process (engraving process) is performed on the outer surface of the bottom portion 6 to form a recessed portion 8 so that the bottom portion 6 is located in the middle of the cylindrical portion 5. The ironing in steps 3 and 4 is the ironing in the direction from the bottom portion 6 toward the cylindrical portion 5. Then, in the step 6, reverse ironing (ironing in the opposite direction to the ironing in the previous steps, ie, ironing in the direction from the cylindrical portion 5 to the bottom portion 6) is applied, and the squeezed meat is added to the cylindrical portion 5 rather than the outer surface of the bottom portion 6. By escaping to the opposite side, a notch-shaped sink mark 11 is formed in the inner surface corner of the cup-shaped material, and a protruding portion 10 protruding from the outer surface of the bottom portion to the side opposite to the cylindrical portion 5 is formed. The cup-shaped material thus obtained is indicated by reference numeral 9. Then, in step 7, step 6
In the same process as or after the ironing process, the cup-shaped material 9
A shearing force is applied between the bottom portion 6 and the cylindrical portion 5 to cut and separate the bottom portion 6 from the cylindrical portion 5 at the position of the notch-shaped sinker 11. The hollow cylindrical part thus obtained is designated by the reference numeral 10,
The fracture surface is indicated by reference numeral 11, and the corners of the end portion where the bottom portion 6 was located are indicated by reference numerals 12 and 13. The corners 12 and 13 are desired to be right angle pin angles. In step 8, ironing may be further performed to obtain the final hollow cylindrical part 10.

The above steps may take the following combinations and orders, and any of the following cases is included in the present invention. Reverse ironing f and cup bottom trim punching g are performed in the same step. Material punching a, trim d, and diaphragm b are performed in the same process. The ironing 2 + trim d and diaphragm b are performed in the same process. Omit the ironing 2. The coining d is performed and the reverse ironing f is omitted. Omit the ironing 3h.

Next, each embodiment of the present invention will be described. The first embodiment of the present invention comprises at least one of the steps a, b, c or d, and steps f and g. And especially f,
The step g is important. In the first embodiment, as shown in FIGS. 2 to 4, the cylindrical portion 5 of the cup-shaped material 4 is squeezed in the direction of the bottom portion 6, and the squeezed meat is released to the side opposite to the cylindrical portion 5 with respect to the outer surface of the bottom portion. A meat sink 11 is formed on an inner surface corner of the cup-shaped material 5, and a protruding portion 10 protruding from the outer surface of the bottom portion in a direction opposite to the cylindrical portion 5 is formed. Then, at the same time as or after the ironing, a shearing force is axially applied between the bottom portion 6 of the cup-shaped material 9 and the cylindrical portion 5, and the bottom portion 6 is cut (sheared) from the cylindrical portion 5 at the portion of the meat sink 11. Cutting), separate. Since the hollow cylindrical part 10 is formed by ironing, the accuracy of the inner and outer diameters is very high, and the tolerance is 20 microns or less.

2 to 4 also show an apparatus for carrying out the method of the first embodiment. The hollow cylindrical component manufacturing apparatus of the first embodiment includes an inner punch 21, an outer punch 22, and a die 23. The inner punch 21 has a tip surface 21 a that is pressed against the inner surface of the bottom portion 6 of the cup-shaped material 4, and an outer peripheral surface 21 b that has a diameter substantially equal to the inner diameter of the hollow cylindrical component 10. The inner punch 21 is inserted into the cup-shaped material 4 during reverse ironing f and during bottom punching g. The outer punch 22 has a tip surface 22a that is pressed against the outer surface of the bottom portion 6 of the cup-shaped material 4, a step surface 22c that is provided midway in the axial direction, and a hollow cylindrical component 10 that is located at the tip end of the step surface 22c and has a diameter. 22d of the outer peripheral surface of the tip portion which is made substantially equal to the inner diameter of
And the rear part from the step surface 22c (the part far from the front end surface 22a)
The rear outer peripheral surface 22b has a diameter substantially equal to the outer diameter of the hollow cylindrical component 10. The die 23 has an ironing portion 23 having an inner diameter substantially equal to the outer diameter of the hollow cylindrical part 10.
a. 24 is an ejector.

The inner punch 21 and the outer punch 22 are
It is movable in the axial direction independently of each other, and is movable in the axial direction relative to the die 23. in this case,
The die 23 may be moved as shown in FIG. 3, or the inner punch 21 and the outer punch 2 may be moved as shown in FIG.
2, the cup-shaped material 4 may be moved. In the case of FIG. 3, the inner punch 21 and the outer punch 22 hold the bottom portion 6 of the cup-shaped material 4 stationary, and while moving the die 23 upward, the squeezing portion 23a of the die 23 causes the cylindrical portion of the cup-shaped material 4 to move. Squeeze 5 toward bottom 6 (reverse ironing). At this time, the portion near the bottom of the cylindrical portion 5 bulges outward in the radial direction to form the bulged portion 14, but when the bulged portion 14 is squeezed, the meat flows in the opposite direction to the cylindrical portion 5 and the bottom surface of the cup-shaped material is squeezed. A protruding portion 10 is formed so as to protrude in the opposite direction to the cylindrical portion 5. In order to allow the meat to flow, the outer punch 22 has a diameter of the tip portion from the step surface 22c that is substantially equal to the inner diameter of the cylindrical portion.

During reverse ironing, the meat of the bulging portion 14 escapes toward the space around the tip of the outer punch, so that the inner corner of the cup-shaped material 4 (the corner between the inner surface of the bottom portion 6 and the inner surface of the cylindrical portion 5) is broken. A sink mark 11 is formed, the tip becomes a sharp notch, and the axial component force due to ironing exceeds the shearing force of the bottom portion 6 to cause a crack. In addition, even if the workability is such that cracks do not occur, the notch due to the sink mark serves as the starting point of fracture during shearing in the next step, which controls the site where the fracture surface is generated and can also reduce the shear fracture force. Meat sink 11
Is always directed obliquely outward (inward in the plate thickness of the bottom 6 and outward in the radial direction), so the fracture surface 1 after fracture
1 (see FIG. 1) does not project radially inward from the inner peripheral surface of the hollow cylindrical component 10. Therefore, the hollow cylindrical component 10 can be used as it is as a hollow cylindrical component which slides the inner peripheral fitting component without cutting. Then, a crack 15 (see FIG. 3) on the fracture surface 11
Although a jagged surface remains at the part of the above, this can be an oil holding surface convenient for holding lubricating oil and the like.

In the second embodiment of the present invention, as shown in FIG. 5, a guide portion 23b extending from the ironing portion 23a to the outer punch 22 side is formed in the die 23, and when the protrusion 10 is formed during ironing. The guide portion 23b is a method of guiding the protrusion 10 so that the meat flows in the axial direction. Regarding the apparatus, the guide portion 23b has an inner diameter larger than the inner diameter of the ironing portion 23a and larger than the outer diameter of the pre-process material by about 0.01 to 0.02 mm, and extends in the axial direction. The flow of meat is regulated and controlled so that the bulging portion 14 at the time of reverse ironing does not face outward in the radial direction but faces in the direction away from the cylindrical portion 5 from the bottom surface of the cup-shaped material in the axial direction. Fig. 7 shows the relationship between the die introduction angle θ and the ironing rate.
In order to generate the sink mark 11 and the crack due to the shearing force, for example, when the die introduction angle θ is 15 °, the ironing rate of 25% or more should be given to the cylindrical portion 5 of the material. To The second embodiment corresponds to the case where there is no punch protrusion.

The third embodiment of the present invention is shown in FIGS. 5, 6 and 8.
As shown in FIG. 3, in the step of forming the protrusion 10 and the subsequent steps (the step of shearing separation g and the step of further pressing the end of the hollow cylindrical part with the outer punch 22 in the axial direction after the separation at that time), Insert the tip corners 12 and 13 into the die 23
And a stepped surface 22c of the outer punch 22 and an outer peripheral surface 22d of the outer punch tip end portion are regulated to form a substantially right-angled portion. For this reason, as shown in FIGS. 5 and 6, the stepped surface 22c of the outer punch 22 and the outer peripheral surface 22d at the tip of the stepped surface 22c are orthogonal to each other. The protrusions 10 are filled with the meat, and the right angled corners of the corners 12 and 13 appear. Therefore, the shape of the tip portion is a right angle pin angle shape with no sink mark or flash and with high accuracy.

In the fourth embodiment of the present invention, as shown in FIGS. 9 to 12, at least one of the outer punch 22 and the inner punch 21 (in FIGS. 9 to 12, the outer punch 22 is used).
The projections 25 projecting toward the bottom 6 of the cup-shaped material 4 are formed on the peripheral edge of the bottom 6
Shearing and separating step from the cylindrical portion 5 of the (step g in FIG. 1)
In this method, the portion to which the shearing force is applied is localized and the shearing force is concentrated to control the fractured portion and to make it possible to fracture with a smaller shearing force. Protrusion 2
The surface of 5 constitutes a part of the front end surface of the punch. As a device, the outer punch 22 and the inner punch 21 are provided with a projection 25 formed on at least one of the peripheral edge portions thereof so as to project in the direction in which the bottom portion 6 of the cup-shaped material 4 is inserted. The shape of the protrusion 25 is 25A with a sharp tip as shown in FIG. 10, 25B with a trapezoid with a flat end as shown in FIG. 11, or 25 with a rounded tip as shown in FIG.
It may be either C or. Projection 25A with a sharp tip
The angle α of is preferably small in order to concentrate the load, but if it is made too small, the mold may be damaged.
It is preferable that the angle is about 5 °. Flat protrusion 25B, round protrusion 25
C is excellent in that mold wear is unlikely to occur and mold breakage is unlikely to occur, and in the case of R, 0.3 to 0.5 mm is preferable.

When the bottom portion 6 is pressed with a punch having the protrusions 25, the protrusions 25 are slightly pushed into the bottom portion 6, so that the meat sink 1
The crack 15 generated from No. 1 propagates toward the tip of the bite portion formed by the protrusion 25. Thereby, the fracture surface 11 (see FIG. 1) can be further controlled. Further, the breaking load due to the projection 25 is lower than that in the case without the projection as in the characteristic with the projection in FIG. 7. Therefore, it is possible to perform molding and breaking with a press machine having a low load capacity.
Further, by reducing the ironing rate, it is possible to reduce the material plate thickness, reduce the volume of the material bottom portion 6 that becomes scrap, and improve the yield. This reduces costs. Further, since the length of the meat sink 11 may be reduced, the accuracy of the inner diameter of the product can be further improved.

In the fifth embodiment of the present invention, as shown in FIGS. 13 and 14, a land portion 26 (a part of the projection) is further provided continuously to the projection 25 of the fourth embodiment, and the projection is stepped. The protrusion 27 is provided to control the meat flow of the bottom portion 6. Reverse ironing (step f in FIG. 1) is performed while sandwiching the bottom portion 6 of the cup-shaped material 4 with the inner punch 21 and the outer punch 22 at a pressure equal to or higher than the yield point of the material. In this case, the protrusions 25 of the stepped protrusions 27 of the inner punch 21 match the meat flow in the sinking direction, and the lands 26 exert a local pressure on the material. Angle j of protrusion 25
Is preferably 30 ° to 45 ° (angle 30 in the fourth embodiment).
Same as the reason for ° ~ 45 °). Further, the width k of the land portion 26 can adjust the magnitude of the local pressure. By providing the land portion 26, it is possible to cause a considerable amount of meat to flow from the bottom portion 6 as well, to promote the generation of the meat sink 11 and also to send the meat to the protruding portion 10 to increase the volume of the protruding portion 10. Can be increased. Also, the angle j of the protrusion 25 and the width k of the land portion 26
Can be controlled more easily to control the occurrence of the sink mark 10 and the crack 15.

In the sixth embodiment of the present invention, as shown in FIGS. 15 to 17, the cylindrical portion 5 of the cup-shaped material 4 is held with the entire bottom surface of the cup-shaped material 4 being in contact with the end surface 22a of the outer punch 22. An axial compressive force is applied to the bottom portion 6 in the direction of the bottom portion, and the portion 14 near the bottom portion of the cylindrical portion 5 is buckled and bent outward in the radial direction to form a radially outward bulging portion 14 ′, and then the cup-shaped material. This is a method in which the radially outwardly bulged portion 14 ′ of the cylindrical portion 5 of No. 4 is shear cut by the die 23 and the outer punch 22. The axial compressive force may be ironing by the die 23 or the ejector pin 24. The inner surface of the radially outward bulging portion 14 ′ is positioned outside the outer punch outer peripheral surface 22 b, and the bottom portion 6 is cut by cutting in this state.
And the cylindrical portion 5 are separated. After the separation, the outer diameter surface of the bottom portion 6 and the outer peripheral surface of the cylindrical portion 5 have the same diameter due to the cutting in the same shearing step, and the separated bottom portion 6 can be used as a lid of the cylindrical portion 5.

In the apparatus for carrying out the method of the sixth embodiment, the inner punch 21 has an outer peripheral surface 21b having a diameter substantially equal to the inner diameter of the hollow cylindrical part 10. Outer punch 22
Is an outer corner surface 2 having a diameter substantially equal to the outer diameter of the hollow cylindrical component 10.
With 2b. Further, the die 23 has an ironing portion 23a having an inner diameter substantially equal to the outer diameter of the outer punch 22, and the cup-shaped material 4 is located closer to the outer punch 22 than the ironing portion 23a.
It has an escape portion 23c composed of a surface which is escaped radially outward so as to allow the buckling deformation of the cylindrical portion 5 outward in the radial direction. As shown in FIG. 16, when the cylindrical portion 5 of the cup-shaped material 4 is squeezed by the squeezing portion of the die 23, the cylindrical portion 5 is molded with high precision, and the bottom portion of the cylindrical portion 5 is radially outward. To form a radially outwardly bulged portion 14 'which is buckled and bent. Further, when the die 23 is relatively moved to the outer punch 22 side, the die 23 and the outer punch 22 shear-cut the radially outward bulging portion 14 ′, as shown in FIG.
A hollow cylindrical component 10 having a highly accurate shape and size can be formed, and a lid 6 ′ having the same outer diameter as that of the hollow cylindrical component 10 can be formed.

[0021]

According to the method of the first aspect of the present invention, the cylindrical portion of the cup-shaped material is reversely ironed to form a sink mark extending obliquely outward at the inner corner of the cup-shaped material, and the bottom portion is used as the starting point of the fracture. Since it was separated from the cylindrical part, the accuracy of the hollow cylindrical part can be increased by ironing, the fracture surface can be prevented from protruding to the inner peripheral surface due to the oblique outer meat sink, and the fracture property can be stabilized. Due to the total effect of the above, it is possible to provide a highly accurate hollow cylindrical component without requiring cutting. According to the method of claim 2, since the die is provided with the guide portion, the meat of the ironing can be released substantially in the axial direction, and the protruding portion protruding in the axial direction from the bottom surface of the cup-shaped material can be formed. The protrusion can form one end of the hollow cylindrical part and the sink mark can be formed approximately axially (but obliquely outward). According to the method of claim 3, since the stepped surface of the outer punch and the outer peripheral surface of the tip end thereof are orthogonal to each other, the corner portion at one end of the hollow cylindrical component can be formed into a right angle pin angle. According to the method of claim 4, since at least one of the inner punch and the outer punch is formed with the projection protruding toward the bottom of the cup-shaped material, the condition of shearing separation from the cylindrical portion of the bottom of the cup-shaped material can be controlled. . According to the method of claim 5, a radial outward bulging portion is formed by applying an axial compressive force to the cylindrical portion of the cup-shaped material, and then the radially outward bulging portion is sheared and separated by the die and the outer punch. As a result, a highly accurate hollow cylindrical part can be formed by ironing, the bottom part and the cylindrical part can be separated, and the bottom part can be used as it is as a lid having the same outer diameter as that of the hollow cylindrical part. According to the apparatus of claim 6, the method of claim 1 is implemented to obtain the effects of the method of claim 1. According to the apparatus of claim 7, the method of claim 2 is implemented to obtain the effect of the method of claim 2. According to the apparatus of claim 8, the method of claim 3 is implemented to obtain the effect of the method of claim 3.
According to the apparatus of claim 9, the method of claim 4 is implemented to obtain the effect of the method of claim 4. According to the apparatus of claim 10, the method of claim 5 is implemented to obtain the effects of the method of claim 5.

[Brief description of drawings]

FIG. 1 is a process drawing of a method for manufacturing a hollow cylindrical component applicable to all the examples of the present invention.

FIG. 2 is a cross-sectional view showing a method for manufacturing a hollow cylindrical part and an apparatus for carrying out the method according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view showing the initial and final stages of the reverse ironing process of the method for manufacturing a hollow cylindrical component according to the first embodiment of the present invention.

FIG. 4 is a sectional view showing the initial and final stages of the reverse ironing process of another example of the method for manufacturing a hollow cylindrical component according to the first embodiment of the present invention.

FIG. 5 is a partial cross-sectional view of a method and apparatus for manufacturing a hollow cylindrical part according to second and third embodiments of the present invention.

FIG. 6 is a partial cross-sectional view of a method and apparatus for manufacturing a hollow cylindrical part according to second and third embodiments of the present invention.

FIG. 7 is a graph showing the relationship between the ironing rate and the die introduction angle.

FIG. 8 is a partial cross-sectional view of a hollow cylindrical component manufactured by the method for manufacturing a hollow cylindrical component according to the third embodiment of the present invention.

FIG. 9 is a partial cross-sectional view of a method and apparatus for manufacturing a hollow cylindrical component according to a fourth embodiment of the present invention.

FIG. 10 is a cross-sectional view showing an example of a protrusion of a hollow cylindrical component manufacturing apparatus according to a fourth embodiment of the present invention.

FIG. 11 is a cross-sectional view showing another example of the protrusion of the hollow cylindrical component manufacturing apparatus according to the fourth embodiment of the present invention.

FIG. 12 is a cross-sectional view showing still another example of the protrusion of the hollow cylindrical component manufacturing apparatus according to the fourth embodiment of the present invention.

FIG. 13 is a partial cross-sectional view in the case where the protrusion is a stepped protrusion in the method and apparatus for manufacturing a hollow cylindrical component of the fourth embodiment of the present invention.

FIG. 14 is a cross-sectional view showing a stepped protrusion of FIG.

FIG. 15 is a cross-sectional view of a method and apparatus for manufacturing a hollow cylindrical part according to a fifth embodiment of the present invention.

16 is a partial cross-sectional view showing a state in which a radially outward bulging portion is formed on the cup-shaped material by the method and apparatus of FIG.

FIG. 17 is a partial cross-sectional view showing a state in which the radially outward bulging portion is sheared and cut by the method and device of FIG. 15.

FIG. 18 is a cross-sectional view showing an example of a conventional method for manufacturing a hollow cylindrical component.

FIG. 19 is a cross-sectional view showing another example of a conventional method for manufacturing a hollow cylindrical component.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flat plate 4 Cup-shaped material 5 Cylindrical part 6 Bottom part 10 Hollow cylindrical part 11 Meat sink 14, 14 'Radially outward swelling part 21 Inner punch 22 Outer punch 23 Die 23a Ironing part

Claims (10)

[Claims] 1. A cup-shaped material having a bottom portion and a cylindrical portion is formed from a flat plate-shaped metal material, and the cylindrical portion of the cup-shaped material is squeezed toward the bottom portion to squeeze meat from the outer surface of the bottom portion into the cylinder. To escape in the opposite direction to the part, to form a sink mark on the inner surface corner of the cup-shaped material, and to form a protruding part that protrudes in the opposite direction to the cylindrical part from the bottom outer surface, at the same time as or after the ironing. A method for manufacturing a hollow cylindrical component, comprising: applying a shearing force between the bottom portion of the cup-shaped material and the cylindrical portion to cut and separate the bottom portion from the cylindrical portion at the sink mark portion. 2. A guide part extending from the ironing part to the outer punch side is formed in the die, and when the protruding part is formed in the ironing, the guide part guides the protruding part to allow meat to flow in the axial direction. The method for manufacturing a hollow cylindrical component according to claim 1. 3. A step of forming a step portion on an outer punch that is pressed against the bottom portion of the cup-shaped material, forming a guide portion extending from the ironing portion to the outer punch side on the die, and forming the protrusion. In the subsequent steps, the tip corner portion of the protrusion is regulated by the guide portion of the die, the step surface of the outer punch, and the outer peripheral surface of the tip portion from the step surface of the outer punch to be a substantially right angle portion. The method for manufacturing a hollow cylindrical component according to claim 1. 4. A projection projecting in a direction in which the bottom portion of the cup-shaped material is pushed in is formed on at least one of an inner punch and an outer punch that are pressed against the bottom portion of the cup-shaped material, and the projection is formed from the cylindrical portion of the bottom portion. 2. The method for manufacturing a hollow cylindrical component according to claim 1, wherein a shearing force generating condition is controlled by the protrusion in the cutting and separating steps. 5. A cup-shaped material having a bottom portion and a cylindrical portion is formed from a flat metal material, and the cup is attached to the cylindrical portion of the cup-shaped material with the entire bottom surface of the cup-shaped material being in contact with the outer punch. A compressive force is applied in the direction of the bottom of the cylindrical material to buckle and bend a portion of the cylindrical portion in the vicinity of the bottom outward in the radial direction to form a radially outwardly bulged portion, and Shearing the radially outwardly bulged portion of the cylindrical portion with a die and the outer punch,
A method for manufacturing a hollow cylindrical component comprising steps. 6. An apparatus used for manufacturing a hollow cylindrical component from a cup-shaped material having a bottom and a cylindrical portion, the hollow having a tip end surface pressed against the inner surface of the bottom of the cup-shaped material. An inner punch having an outer diameter substantially equal to the inner diameter of the cylindrical part, a tip surface pressed against the outer surface of the bottom portion of the cup-shaped material, and a step surface in the middle of the axial direction. An outer punch having an outer diameter substantially equal to the inner diameter of the hollow cylindrical component and an outer diameter of the rear portion of the step surface substantially equal to the outer diameter of the hollow cylindrical component, and an inner diameter substantially equal to the outer diameter of the hollow cylindrical component. An apparatus for manufacturing a hollow cylindrical part, comprising: a die having an ironing part. 7. The die extends axially from the ironing portion to the outer punch side and has an inner diameter larger than an inner diameter of the ironing portion so that meat meat squeezed by the ironing portion flows radially outward. The apparatus for manufacturing a hollow cylindrical component according to claim 6, further comprising a guide portion that suppresses the hollow cylindrical component. 8. The apparatus for manufacturing a hollow cylindrical component according to claim 6, wherein the step surface of the outer punch and the outer peripheral surface of the tip portion from the step surface are orthogonal to each other. 9. The method according to claim 6, wherein at least one of the inner punch and the outer punch has a protrusion projecting in a direction in which the bottom portion of the cup-shaped material is pushed in at a position corresponding to an inner diameter of the hollow cylindrical component. Manufacturing equipment for hollow cylindrical parts. 10. An apparatus used to manufacture a hollow cylindrical component from a cup-shaped material having a bottom and a cylindrical portion, the hollow having a tip surface pressed against the inner surface of the bottom of the cup-shaped material. An inner punch having an outer diameter substantially equal to the inner diameter of the cylindrical part, an outer punch having an outer diameter substantially equal to the outer diameter of the hollow cylindrical part, the outer punch having an end face pressed against the entire bottom surface of the cup-shaped material. A die having an ironing portion having an inner diameter substantially equal to the outer diameter of the die, and the outer punch side of the ironing portion is escaping radially outward so as to allow buckling deformation of the cup-shaped material radially outward. An apparatus for manufacturing a hollow cylindrical part, comprising: