JPH06210389A - Manufacture of bottomed cylindrical part - Google Patents

Abstract

PURPOSE:To efficiently manufacture a bottomed cylindrical part at low cost ensuring a sufficiently large outside flat part of bottom in a manufacturing method by which the part is manufactured by press work using a plate like material. CONSTITUTION:An intermediate product 22 whose length is longer than the length of a work 10 of finished formed product and a corner part 46 of a cylindrical part 42 and bottom part 44 whose radius is larger than the radius of the work 10 is pre-liminarily drawn from the plate like material to be bottomed cylindrical shape. After trimming an outward flange 48 of the intermediate product 22 by a die 56 and punch 60 whose inside and outside diameters are equal to the diameters of the work 10, the cylindrical part 42 is pressurized in the axial direction to flow pads to the corner part 46 side by forging and the intermediate product 22 is formed in the wanted shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a bottomed cylindrical part, and more particularly to a method of manufacturing a plate-shaped material by pressing.

[0002]

2. Description of the Related Art When manufacturing a bottomed cylindrical part having a circular hole at the bottom, for example, a pipe material having an inner diameter substantially equal to the hole diameter of the circular hole is prepared and the inner portion of the cylindrical part is formed by boring a lathe. There is a method of cutting the peripheral surface to a predetermined size. FIG. 9 is a cross-sectional view showing an example thereof, in which the lattice striped portion of the pipe material in the figure is removed by cutting, and the tubular portion 102 and the bottom portion 104 of the bottomed tubular component 100 are formed to have predetermined dimensions.

[0003]

However, in the method of manufacturing a pipe material by cutting as described above, the manufacturing cost is increased in combination with the time required for processing and the high cost of the pipe material itself. This is a big problem especially when mass production is performed.

On the other hand, it is conceivable that the plate material is subjected to a drawing process by a press, and in that case, as in the bottomed tubular part 110 shown in FIG. Since the radius of the corner portion 116 with the bottom portion 114 is inevitably large, the flat portion 118 outside the bottom portion 114 is narrowed over the entire circumference from the outer diameter of the tubular portion 112 by the above radius. For this reason, when a large flat surface portion is required, the flat surface portion 12 is used in addition to increasing the outer diameter of the tubular portion 122 as in the bottomed tubular component 120 shown in FIG.
4 could not be secured sufficiently large. Also,
Although it is possible to manufacture a bottomed tubular part by forging, in that case, it is difficult to mold it into a thin wall, a desired shape cannot be manufactured, and the part weight becomes heavy.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a bottomed cylindrical part which can be manufactured inexpensively and efficiently while securing a sufficiently large flat portion outside the bottom portion. It is to provide a manufacturing method of.

[0006]

In order to achieve the above object, the gist of the present invention is a method for producing a bottomed tubular component from a plate-shaped material, which comprises: An intermediate bottomed tubular shape that has been drawn and has a tubular portion longer than the bottomed tubular component and a corner portion between the tubular portion and the bottom having a radius larger than that of the bottomed tubular component. A drawing step for manufacturing a product, and (b) fitting the intermediate product from the bottom side into a die having a molding surface having a shape corresponding to the shape of the outer peripheral surface of the bottomed tubular component excluding the opening-side end surface, A punch having a molding surface having a shape corresponding to the shapes of the inner peripheral surface and the end surface on the opening side of the bottomed tubular component is fitted into the intermediate product and the die, and the intermediate product is forged, and the intermediate product tube By pressing the shaped part in the axial direction to allow the excess thickness to flow to the corner side. Ri is to have a shape out shaping into an intended shape.

Further, preferably, in the drawing step, an intermediate product having an outward flange at an opening end of the tubular portion is manufactured, and in the shaping step, the outward flange is trimmed by the punch and a die. After that, the forging process is performed.

[0008]

In the method for manufacturing a bottomed cylindrical part, the plate material is first drawn in the drawing step so that the length of the cylindrical part is longer than that of the bottomed cylindrical part. Further, a bottomed tubular intermediate product is manufactured in which the radius of the corner portion between the tubular portion and the bottom is larger than the bottomed tubular component. After that, in the shape forming step, the intermediate product is fitted from the bottom side into a die having a molding surface having a shape corresponding to the shape of the outer peripheral surface of the target bottomed cylindrical part excluding the end surface on the opening side, and A punch having a molding surface having a shape corresponding to the shape of the inner peripheral surface and the end surface on the opening side of the bottom tubular part is fitted into the intermediate product and the die, and the intermediate product is subjected to forging processing to form a tubular product of the intermediate product. The part is pressed in the axial direction and the excess thickness is caused to flow toward the corner part side, whereby the target part is molded.

[0009] Here, when the intermediate product is compressed and molded on the molding surfaces of the die and the punch in the shaping step, the surplus of the tubular portion of the intermediate product is applied to the corner portion on the bottom side. From this, it is possible to obtain a bottomed cylindrical part having a desired shape by molding the die in the same shape as the corners on the molding surface and filling the surplus thickness in the reduced thickness portion at the time of drawing. As a result, for example, if the radius of the corner on the die side is substantially zero, the corner of the bottomed tubular component is also molded to have a radius of substantially zero, and the outer diameter of the flat surface outside the bottom is reduced to the cylinder. The outer diameter of the shaped portion can be made substantially the same. Therefore, according to the manufacturing method of the present invention, it is possible to sufficiently secure the flat portion outside the bottom portion without increasing the diameter of the tubular portion, and the bottomed tubular portion having such a small radius of the corner portion. The parts can be manufactured inexpensively and efficiently.

In the case where an intermediate product having an outward flange at the opening end of the tubular portion is manufactured in the drawing step, and the forging process is performed after trimming the outward flange with a punch and a die in the shaping step. Has
The trimming allows the excess thickness of the tubular portion to be substantially even in the circumferential direction, so compared to the case where the open end shape of the tubular portion varies after drawing like an intermediate product without an outward flange. The flow of the extra thickness during the forging process is well performed over the entire circumference of the intermediate product, and the accuracy of shape formation is improved.

[0011]

An embodiment to which the method of the present invention is applied will be described in detail below with reference to the drawings. 2 is a perspective view of the final workpiece 8 to be manufactured, which is obtained from the bottomed tubular part 10 shown in FIG. The bottomed tubular component 10 includes a tubular portion 12 having a cylindrical shape and a bottom portion 14 provided at one end of the tubular portion 12, and the tubular portion 12 and the bottom portion 14 are substantially uniform. Has a wall thickness. Cylindrical part 12 and bottom part 1
The radius of the corner portion 18 connected to 4 is substantially zero, and both the inside and the outside are substantially right angles in the sectional shape including the axis. The work 8 has a circular hole 16 penetrating in the axial direction in the central portion of the bottom portion 14 of the bottomed tubular component 10.

The bottomed tubular part 10 is manufactured by pressing a blank 20 as a plate-shaped material shown in FIG. The blank 20 has a disk shape and a plate thickness of about 1.4 to 3.2 mm, and is obtained by punching a punching press or the like from a band-shaped metal plate to an outer diameter of a predetermined size.

5 and 6 are cross-sectional views showing a drawing process for manufacturing the intermediate product 22 by subjecting the blank 20 to a predetermined drawing process. In this drawing process,
First, when the blank 20 is supplied to the pressing device 24 of FIG. 5 and positioned on the die 26 by a holding member (not shown) and the punch 28 is lowered, the blank 20 is placed between the die 26 and the punch 28. It is sandwiched and pressed with a predetermined pressing pressure, and the center part thereof is formed by drawing so as to form a partial spherical surface protruding toward one surface side from the surrounding part. The blank 20 subjected to the primary drawing process as shown in FIG. 5 is then sent to the press device 30 shown in FIG.
Secondary drawing is performed.

In the press device 30, as shown in FIG. 6 (a), the blank 20 is pressed by the punch 34 which is lowered while the peripheral edge portion is pressed by the wrinkle pressing plate 32 with an appropriate wrinkle pressing force. By pressing the central portion toward the die 36, drawing is performed so as to have a bottomed cylindrical shape having an outer diameter substantially equal to that of the bottomed cylindrical component 10 of FIG. Here, the radius of the tip-side corner portion 38 of the punch 34 and the radius of the opening-side corner portion 40 of the die 36 are respectively preset to the optimum values in the above-mentioned drawing work, and the blank 20 is free from material breakage and wrinkles. It is squeezed well into the die 36 without any occurrence. The same figure (b)
Indicates that the drawing has been completed completely. By this secondary drawing, the predetermined shape in the drawing process, that is, the length of the cylindrical portion 42 in the axial direction of the bottomed cylindrical part 1 is obtained.
0 is longer than the tubular portion 12, and the tubular portion 42 and the bottom portion 4 are
The outer radius of the corner 46 with 4 is the bottomed tubular part 10
The intermediate product 22 is obtained by molding into a bottomed cylindrical shape having a radius larger than the radius of the corner portion 18 (= approximately zero). Further, as is clear from FIG. 6, at the opening end of the tubular portion 42,
The portion of the blank 20 that was held by the wrinkle holding plate 32 remains as the outward flange 48.
In the present embodiment, the intermediate product 22 is formed by drawing in two steps, but the intermediate product 22 is formed by drawing in one step or three or more steps in consideration of the material of the blank 20 and the shape of the work 8. You can also do it.

FIG. 1 is a cross-sectional view showing a step of forming the bottomed tubular part 10 by further pressing the intermediate product 22 to form it, and a pressing device 50 for performing the step. The pressing device 50 includes a die 56 having a molding surface 54 having a shape corresponding to the shape of the outer peripheral surface of the bottomed tubular component 10 excluding the opening-side end surface 52 of FIG. 3, the inner peripheral surface of the bottomed tubular component 10, and the die 56. A molding surface 58 having a shape corresponding to the shape of the end surface 52.
And a punch 60 having a stepped shape. Cylindrical inner peripheral surface 62 of molding surface 54 of die 56
The corner portion 66 between the bottom surface 64 and the bottom surface 64 is formed in a so-called pin angle shape having a radius of substantially zero, like the corner portion 18 of the target bottomed tubular component 10, and the tip of the small diameter portion 60 a of the punch 60. The corner portion 68 on the side is also formed in a pin angle shape with a radius of substantially zero. Large diameter part 60 of punch 60
The outer diameter of b is substantially equal to the inner diameter of the inner peripheral surface 62 of the die 56, and the outer peripheral end 70 of the step between the small diameter portion 60a and the large diameter portion 60b and the opening end 72 of the inner peripheral surface 62 are , Each function as a cutting edge.

In the shape forming step, as shown in FIG. 1A, when the punch 60 is lowered to the die 56 side with the intermediate product 22 fitted in the die 56 from the bottom portion 44 side,
The intermediate product 22 is pushed down to the die 56 side in a state where the outer peripheral end 70 of the punch 60 is in contact with the outward flange 48 of the tubular portion 42, and the outer peripheral end 70 and the open end 72 of the die 56 are moved as they descend. Thereby, the outward flange 48 is sheared, and the intermediate product 22 is trimmed as shown in FIG. By this trimming, the extra thickness A on the open end side of the tubular portion 42 is substantially evened in the circumferential direction. Then, the punch 60 is pushed further in and the bottom portion 44
When a predetermined press pressure is applied to the intermediate product 22 that is in contact with the bottom surface 64 of the die 56, the bottomed tubular component 10 having the desired shape is obtained as shown in FIG.

Specifically, the cylindrical portion 42 is formed by the punch 60.
Is pressed in the axial direction, the excess thickness A on the opening end side is caused to flow toward the corner portion 46 side, and a considerable amount of the excess thickness A is formed in the corner portion 46 and the die 56 having a relatively large initial radius. By filling the gap between the surface 54 and the corner 66 of the pin angle, the corner 46 of the intermediate product 22 is molded in accordance with the shape of the corner 66, and the target shape, that is, the bottomed tubular part. 10 corners 18
Similarly, the radius is almost zero. Although slightly, the forming surface 58 of the punch 60, more specifically, the small diameter portion 6
The extra thickness B is also made to flow outward from the inner portion of the corner portion 46 pressed by the corner portion 68 of 0a. Further, the wall thickness of the cylindrical portion 42 of the intermediate product 22 is thinned by the drawing process, but this can be restored to the desired wall thickness by the above-mentioned excess thickness A. The length dimension of the tubular portion 42 of the intermediate product 22, that is, the depth dimension of the die 36 is set in accordance with the required amount of excess thickness. As a result, the bottomed tubular component 10 shown in FIG. 3 is manufactured.

Then, the bottomed tubular component 10 is transferred to the punching device 80 shown in FIG. 7 and punched.
In the punching device 80, the circular hole 16 is punched in the bottom portion 14 by the downward punch 84 in a state where the bottomed tubular component 10 is fitted into the die 82 from the bottom portion 14 side. The work 8 shown in FIG. 2 having a final shape is manufactured by the steps up to the punching process.

Here, in this embodiment, by setting the radius of the corner portion 66 on the die 56 side to be substantially zero, the corner portion 18 of the bottomed tubular component 10 can be molded in a state where the radius is substantially zero. The outer diameter of the flat surface portion 86 outside the bottom portion 14 shown in FIG. 7 can be ensured to be substantially the same as the outer diameter of the tubular portion 12. Therefore, according to the method for manufacturing the bottomed tubular component 10 of the present embodiment, the flat portion outside the bottom is sufficiently secured as in the case where the bottomed tubular component 10 is manufactured only by drawing. Therefore, it is not necessary to increase the diameter of the tubular portion, and the bottomed tubular component 10 having a small radius of the corner portion 18 and the work 8 can be manufactured inexpensively and efficiently.

In the drawing step, the intermediate product 22 having the outward flange 48 at the open end of the tubular portion 42 is manufactured, and in the shaping step, the outer peripheral end 7 of the punch 60 is formed.
0 and the opening end 72 of the die 56 trims the outward flange 48, and then the forging process is performed. By trimming the outward flange 48, the excess thickness A of the tubular portion 42 is substantially uniform in the circumferential direction. Therefore, as compared with the case where the open end shape of the tubular portion varies after the drawing process like the intermediate product having no outward flange, the flow of the excess thickness A during the forging process is the intermediate product 22. Is performed satisfactorily over the entire circumference of, and the accuracy of shape formation is improved.

Although one embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be implemented in other modes.

For example, the pressing device 50 of FIG. 1 in the above-described embodiment is provided with a stepped punch 60, and the intermediate product 2
The second tubular portion 42 and the bottom portion 44 were forged at the same time, but the first punch 9 is driven at a different timing, for example, like the press device 90 shown in FIG.
By providing the second punch 94 and the second punch 94, the inner first punch 92 presses the bottom portion 44 of the intermediate product 22 against the bottom surface 98 of the die 96 first, and then the outer second punch 94 causes the cylindrical portion. Forging may be performed by pressing 42.

Further, in the above-described embodiment, the punching process by the punching device 80 of FIG. 7 is performed by the pressing device 50 of FIG.
Although it was carried out separately from the shape forming step by, the punch 60 similar to the punch 84 of FIG. 7 is incorporated in the punch 60 of the press device 50 so that the punching process is performed simultaneously with the forging process. It is also possible.

Further, in the above-described embodiment, the outward flange 48 of the intermediate product 22 is trimmed in the shaping process by the pressing device 50 of FIG. 1, but the trimming is a process different from the forging process. You can do it in.

Further, the work 8 in the above-mentioned embodiment is
It was composed of a cylindrical portion 12 having a cylindrical shape and a bottom portion 14 provided at one end of the cylindrical portion 12, and a circular hole 16 was provided at the center of the bottom portion 14. Also when manufacturing other bottomed cylindrical parts whose surface shape is other than circular or does not have a circular hole in the bottom,
The method of the present invention can be applied.

Further, in the above-described embodiment, the intermediate product 22 having the outward flange 48 at the opening end of the tubular portion 42 is manufactured in the drawing step, and after the outward flange 48 is trimmed in the shaping step. Although the forging process was performed, the blank 20 may be drawn until the flange disappears by the drawing process, and the blank 20 may be forged as it is without trimming, and the outward flange is not necessarily provided.

Although not illustrated one by one, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating a shape forming step in manufacturing the bottomed tubular part of FIG. 3 according to the method of the present invention.
It is a figure which shows the flow of a process in order of (b) and (c).

FIG. 2 is a perspective view showing an example of a workpiece manufactured from the bottomed tubular component of FIG.

FIG. 3 is a perspective view showing a bottomed cylindrical part manufactured according to the method of the present invention.

FIG. 4 is a perspective view showing a plate-shaped material for manufacturing the bottomed tubular component of FIG.

5 is a cross-sectional view illustrating a primary drawing process in a drawing process when the bottomed tubular part of FIG. 3 is manufactured by using the plate-shaped material of FIG. 4 according to the method of the present invention.

FIG. 6 is a cross-sectional view illustrating secondary drawing processing performed after the primary drawing processing of FIG. 5, and is a diagram showing a flow of steps in the order of (a) and (b).

7 is a cross-sectional view illustrating a punching step in manufacturing the workpiece of FIG. 2 from the bottomed tubular component of FIG.

FIG. 8 is a cross-sectional view showing another aspect of the shaping process in the method of the present invention.

FIG. 9 is a cross-sectional view illustrating an example of a conventional manufacturing method for manufacturing a bottomed cylindrical part having a circular hole at the bottom by cutting.

FIG. 10 is a cross-sectional view illustrating an example of a conventional bottomed tubular component manufactured by drawing.

FIG. 11 is a cross-sectional view illustrating another example of a bottomed tubular component manufactured by drawing.

[Explanation of symbols]

 10: Cylindrical part with bottom 12,42: Cylindrical part 14,44: Bottom part 18,46: Corner part 20: Blank (plate material) 22: Intermediate product 48: Outward flange 52: Opening end face 54: Molding Surface 56, 96: Die 58: Molding surface 60, 92, 94: Punch

Claims (2)

[Claims] 1. A method for manufacturing a bottomed tubular part from a plate-shaped material, wherein the plate-shaped material is subjected to a drawing process, and the length of the tubular part is longer than that of the bottomed tubular part. A drawing step for manufacturing a bottomed tubular intermediate product in which the radius of the corner portion of the tubular portion and the bottom portion is larger than the bottomed tubular component, and the outer peripheral surface of the bottomed tubular component excluding the opening side end face. A punch having a molding surface having a shape corresponding to the shapes of the inner peripheral surface of the bottomed tubular component and the end surface on the opening side while the intermediate product is fitted from the bottom side into a die having a molding surface having a shape corresponding to the shape. Is inserted into the intermediate product and the die, the intermediate product is subjected to forging, and the tubular portion of the intermediate product is axially pressed to allow the excess thickness to flow toward the corner portion side, thereby achieving a desired shape. Of a bottomed cylindrical part characterized by having a shape forming step Law. 2. In the drawing step, an intermediate product having an outward flange at an opening end of the tubular portion is manufactured, and in the shaping step, the outward flange is trimmed by the punch and a die, and then the forging is performed. The method for manufacturing a bottomed cylindrical part according to claim 1, wherein the bottomed cylindrical part is processed.