US2812059A

US2812059A - Die shaping device

Info

Publication number: US2812059A
Application number: US354769A
Authority: US
Inventors: Biginelli Oreste
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-11-10
Filing date: 1953-05-13
Publication date: 1957-11-05
Anticipated expiration: 1974-11-05

Description

Nov. 5, 1957 o. BlGlNELLl DIE SHAPING DEVICE 4 Sheets-Sheet 1 Filed May 13. 1953 M Em a Fug-4 JM E/v we 0.95s?! Elam/nu Nov. 5, .1957 o. B lGlNELLl 2,812,059

- I DIE SHAPING DEVICE Filed May 13, 1953 4 Sheets-Sheet 2 Nov. 5, 1957 I Y o. BlGlNELLl 2,812,059

(DIE SHAPING DEVICE Filed May 15. 1953 4 Sheets-Sheet 3 Fig-6 ,ZM/nvrm? 025.572- B/auva u 4 Sheefs-Sheet 4 O. BIGINELLI DIE SHAPING DEVICE Nov. 5, 1957 Filed May l3, 195s Unitid States Patent DIE SHAPING DEVICE Oreste Biginelli, Clermont-Ferrand,,France Application May 13', 1953, SerialNo. 354,769 Claims priority, application France November. 10, 19.52

1 Claim. (Cl. 207-6) It is known that parts with an internal and external conical shape can be produced by extruding from a cylindrical length taken from a bar or billet. This cylindrical length is placed in a container or blind die of conical shape corresponding to the external shape of thepart to bemade, and distorted by means of a tool known as a punch provided with an internal cone-shaped form. However, this process possesses the following disadvantages; it only enables conical parts to be made with a relatively thick wall, or parts with too sharp a taper. It has been observed that if an endeavor is made to produce parts with; a relatively thinner wall, the force applied to; the punch very rapidly increases and the tool is. unable. to stand up to it. Should an endeavor be made to obtain a conical shape with a relatively wider angle, cracks. are liable to. appear at the end of the open part of the part. In short, experience has shown that such shapes cannot be obtained by this process when the thickness of the wall falls, below a certain value for a certain opening of the cone. To obtain this, it becomes necessary to. utilize forging processes which are more complex and require atf leasttwo successive operations, and frequently more.

The purpose of the present invention is to obviate this disadvantage.

It relates to a process for manufacturing hollow coneshaped parts comprising distortion by extrudinga primary element, such as a length of bar or billet of cylindrical or other shape in a die by means ofa punch, this process being characterized in that the manufacture comprises. an extrusion phase for the material both in the direction in which the punch moves, as well as the directionopposite to this movement, which enablesthe strain on the punch to be limited and parts to be produced which are thin and sharply tapered.

According to one characteristic of the invention, the manufacturing process comprises two successive stages, carried out on the same machine: a first stage in which the primary element is distorted according to a thick walled rough part by extrusion in the opposite direction of the movement of the punch, and a second stage, in which the walls of this rough part are thinned by extruding the metal both in the direction in which the punch moves, as well as the opposite direction to its movement.

According to another characteristic of the invention, the extrusion stage in both directions is followed by a stage when the finished part is ejected.

The invention also applies to a machine for operating the aforementioned processes or similar processes, characterized by a conical die open at both ends, and two punches opposed coaxially to this die and capable of 'penetrating into this die and withdrawing by movements independent of each other, which enables a rough part to be shaped by the penetration of a first punch into the wide opening of the conical die, the second punch closing the other opening of this die, then achieving an extrusion in both directions, by continuing the movement of the first punch and withdrawing the second punch.

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According to one characteristic of the invention, the first punch has a conical end which corresponds. to the internal shape of the part to be made.

According to another characteristic of the invention, the conical die, on the opposite side to its wide opening, is provided with a cylindrical part in which the second punch slides which has a corresponding cylindrical shape.

The invention also relates to the characteristics hereinafter described and to their various possible combinations.

A machine for operating the process of the invention and articles produced are shown by way of example in. the attached drawing, in which:

Figures 1, 2 and 3 are axial section views of three shapes of conical parts which can be obtained.

Figure 4 is an axial section view of the machine before the punches move.

Figure 5 is an axial section view of this machine after the first working stage.

Figure 6 is an axial section view of this machine after the second working stage.

Figure 7 is an axial section view of the machine in the ejection position.

Figure 1 shows a part with a conical internal and external shape. Figure 2, a part with conical internal and external shape lengthened by a cylindrically shaped part externally on the closed side, and a cylindrically shaped. part internally and externally on the open side. Figure 3 shows a similar part in which the internal shape is notexactly conical but has a slight curve produced by rotation.

Figure 4 shows the machine in position at the beginning of the operation. 1 is a container or die fixed to the frame 2 in a hydraulic press by a threaded ring 3. The die 1 is bored throughout its entire length. From bottom to top, this reaming is first of all cylindrical 4 at a diameter corresponding ot the largest external diameter of the. part to be made. At the top, the. reaming is conical 5 and is shaped like the external part of the part to be made. At upper part the reaming is cylindrical 6. and corresponds to the smaller external diameter of this part.

7 is a punch integral with the lower movable member of the press. A slide 8 is fixed to this member by a threaded nut 9 screwed into this slide 8 and pressing on the baseplate 10 as a punch shoulder 7. This punch 7 consists of a cylindrical brace 11 terminating at its upper end in a cone-shaped part 12. The cylindrical part 11 has a larger diameter than the internal shape of the part to be made and the conical shape is identical to the in ternal conical shape of this part.

13' isa punch integral with the upper press movement. Itis fixed to the slide 14 of this movement by a threaded. nut 15 screwed-into this slide 14 and pressing on the base.- plate 16 as a shoulder for this upper punch. 13. The punch 13 is cylindrical and its diameter is such that it can slide with a minimum play in the upper cylindrical reaming 6 of the die 1.

The primary part is a length of round billet 17 or any other shape taken from a billet, rolled bar or press-drawn piece, according to the metal employed. Its diameter is intermediate between the large and small reaming of the container. This round piece is previously heated if hot extrusion is to take place, and suitably lubricated. For hot work, the die 1 is also heated, preferably by an electric heating system which surrounds it and is shown diagrammatically at 18.

The manufacturing process is as follows:

At the beginning, the members of the machine are in the position of Figure 4. The punch 7 is at its bottom position leaving a suitable clearance under the die 1. The upper punch 13 is also at its bottom position so that its end is partially engaged in the conical reaming 5 of bottom, which is not shown.

The round piece 17 is placed in the clearance left between die 1 and punch 7 properly centered on the axis of these members. The movement of the lower press is operated upwards. The punch 7 pushes the round piece 17 upwards, inserting it in the reaming of the die and toreing it into the conical reaming of the latter. As the punch travels upward the product fills the conical reaming, assumes its shape and stops at the lower end of the upper punch 13. The extrusion of the metal then takes place, the material descends in an opposite direction to the movement of the punch 7, which, at the end of this first stage of the operation, is in the position of Figure 5. The prodnot obtained 19 has a shape corresponding to that which can be obtained by inverse extrusion in a blind die. The wall limited by the internal and external shapes is relatively thick. At this first stage the punch 13 remains motionless and held downwards by the efiort made by the upper press member. This effort must therefore be regulated.

In the second stage of the operation the upper punch 13 is moved to its top position as shown in Figure 6. In this position the upper punch is exactly engaged by its end in the entrance to the top reaming of the die. The punch 7 is again operated upwards finally to assume its top position shown in Figure 6. During this second movement the lower punch 7 efiects a double extrusion of the material; one part of the material of the wall moves upwards in direct extrusion in the direction in which the punch 7 moves, while another part moves downwards in inverse extrusion in a direction contrary to the movement of this punch 7. Finally, the material occupies the free space between the punch and the die, the product 20 internally assuming the exact shape of the punch 7.

Figure 7 shows the stage for extracting the product. The lower punch 7 has been operated downwards to its initial position. The upper punch 13 has then also been operated downwards to its initial position, causing the product 20 to be removed from the container.

The process and machine described above enable the following technical advantages to be obtained:

(1) The first stage produces by inverse extrusion a rough part which. is thinned during the second stage by a double direct and inverse extrusion. Thus, a thin part whose conicity is accentuated can be produced on the same machine and in one operation in two stages.

(2) Extrustion in both directions enables the strain on the punch to be limited, as the material flows in front of the punch at the same time as on the sides of the latter.

(3) The machine enables work to be done at lower temperatures than those usually employed.

What I claim is:

In a machine for manufacturing hollow conical pieces having conical side walls, an open end and a closed end, the combination comprising a die open at two ends and having a conical bore between two cylindrical bores, one of said cylindrical bores having a small diameter and the other cylindrical bore a larger diameter, said conical and cylindrical bores being smooth and continuous and being connected with one another, said conical bore being of a length substantially the length of the conical walls of the article to be formed, a piston maintained in the cylindrical bore of small diameter with its end projecting into said conical bore, a conical cylindrical punch coaxial with said piston, the conical portion of said punch being of a length substantially that of said conical bore, said punch being capable of penetrating a solid billet the size of the cylindrical bore of larger diameter to force the billet into the restricting area of the conical bore of said die While simultaneously piercing the billet accompanied by backward extrusion, until the entering end of said billet engages said piston and the bottom of the piece is formed, means for thereafter displacing said piston while continuing the movement of said conical cylindrical punch whereby the continued movement of the conical punch into the conical bore reduces the width of the space intervening to squeeze the walls of the then pierced billet and thereby create an extrusion of said walls in two directions, one in a direction inversely to the direction of the moving punch and the other in the direction of the moving punch, said last directional movement being accommodated by the displacement of said punch.

References Cited in the file of this patent UNITED STATES PATENTS 54,121 Crooke Apr. 24, 1866 536,278 Friedrich et a1 Mar. 26, 1895 1,151,222 Scrimgeour Aug. 24, 1915 1,321,096 Geer Nov. 11, 1919 1,347,415 Sherman et al. July 20, 1920 1,380,250 Reymond May 31, 1921 1,480,843 Singer Jan. 1, 1924 1,642,696 Rateike Sept. 20, 1927 2,299,105 Muir Oct. 20, 1942 2,368,603 Welsford et al Jan. 30, 1945 2,586,336 Huck Feb. 19, 1952 2,593,730 Cornell Apr. 22, 1952 2,642,647 Culhane June 23, 1953 FOREIGN PATENTS 19,549 Austria Mar. 27, 1905 327,315 Germany Oct. 9, 1920 491,260 France May 28, 1919 534,336 France Mar. 23, 1922 587,618 Germany llov. 6, 193.3 594,670 France Sept. 17, 1925 670,575 Germany Ian. 20, 1939 717,849 Germany Feb. 24, 1942 749,768 Germany Dec. 4, 1944 1,010,338 France June 10, 1952 OTHER REFERENCES Iron Age Magazine, Oct. 19, 1950, Cold extrusion of shells, pp. 69-75.