US2840884A - Apparatus for shaping tubular parts - Google Patents

Description

APPARATUS FOR SHAPING TUBULAR PARTS Filed Nov. 15, 1951' 4 Sheets-Sheet 3 47 2 5 l 4o as July 1, 1958 Filed NOV. 15, 1951 O. BIGINELLI APPARATUS FORSHAPING TUBULAR PARTS 4 Sheets-Sheet 4 i Y! U2) htor rgabe fiigine/h' [:3 W, AL

fli'tornay United States Patent I APPARATUS FOR SHAPING TUBULAR PARTS Oreste Biginelli, Clermont-Ferrand, France Application November 15, 1951, Serial No. 256,582

Claims priority, application France April 17, 1951 2 Claims. (Cl. 29.1.3)

Processes are already known which enable a hollow cylindrical object in the shape of a case to be obtained, starting from a cylindrical metal part.

These known processes consist of compressing this cylindrical metal part between a male part formed by a cylindrical punch having the internal diameter of the case and a female part formed of a die, also cylindrical, whose internal diameter is equal to the external diameter of the case to be produced.

The compressed metal is forced in the opposite direction to the movement of the punch in the annular space comprised between the punch and the die to form the cylindrical wall of this case.

This known process only enables cases to be obtained with the same thickness over the entire length of the cylindrical wall.

The cylindrical metal part can also be compressed against a fixed punch by means of a rammer sliding in the die and forming the bottom of this die.

This known process also only enables cases to be obtained whose cylindrical wall is the same thickness throughout.

In these two known processes, the longer the case, the more difficult it is to maintain correct centering of the punch.

Other known compression processes comprise tw Stages.

A first stage in which a thick walled rough part is shaped between a punch and a first die, and a second stage where the. cylindrical walls of this rough part are elongated in-an open die with a recess between two bores of different diameters. In this known process which enables long and correctly centered cases to be obtained, particles of metal which must e removed after each operation generally remain in'the shoulder of the die connecting the two difierent'bores, so that the case shall not be scratched which is formed in the next operation; owing to this, the output of the. machine is greatly diminished.

Furthermore, this process requires the first'cylindrical parts to be always of the same volume.

Any difference in volume of this first part is actually revealed by a difference in the thickness of the end of the rough part and a difference in the position of'the punch with regard -,to the .die .at the beginning of the secondstage of the work.

These differences are shown by irregularities in the thickness of the cylindrical wall .of the case in the vicinity of the bottom of this case.

The purpose of this invention is to obviate these disadvantages.

It relates to a process for shaping tubular parts with a bottom like cases or sockets, starting from a solid part like a billet or drawn bar, comprising a stage for shaping a hollow roughpart and a stage for elongating this rough part, a process characterized in that this rought part is formed, in the first stage, by drawing the metal of the billet through they annular space made be.-

2,840,884 Patented July 1, 1958 tween the female part and the fixed axial part; the second stage being achieved by drawing the cylindrical walls of this rough part through the same female part by moving the axial part with regard to this female part pressing on the bottom of the rough part.

According to one feature of the invention, the drawing stage of the rough part is achieved by pressing the axial part on the bottom of this rough part, the relating movement of this axial part with regard to the female part, and in this female part the edges of the rough part being pinched between this female part and the axial part.

The invention also relates to a machine for operating the aforementioned processes characterized in that it comprises, on a common frame, two opposed coaxial press cylinders in which two press pistons move, the upper piston being integral with the axial part. The lower piston being integral with the rammer and a coaxial annular female part coaxial to the axial part and the rammer being fixed to the frame of the press.

According to one feature of the invention, the annular female part is fixed to the upper cylinder, which enables this female part to be more easily centered with regard to the axial part, i. e., the regularity of the annular space arranged between the annular female part and the axial part.

According to one embodiment of the invention, the annular female part is formed by an open draw-plate supplied internally on the rammer side with a cylindrical bore of a certain length and forming a cylinder for this rammer, a contracted annular part, with regard to the cylindrical bore continuing this bore on the axial part side.

According to one feature of the invention, the upper Cylinder has an upper end engaged in this cylinder in a sliding manner, this end being integral, through the intermediary of an inlet nozzle of motor fluid, with a cap screwed externally on the cylinder, which enables the stop to be regulated which is formed by this movable end.

According to one feature of the invention, the axial part is formed by a cylindrical rod needle fixed to the upper piston, the end part of this needle being slightly cone-shaped, and having, at the end, in a hollow, the relief to be made on the bottom of the case.

According to another feature of the invention, the rammer is formed by a cylindrical rod terminating at its upper end in a larger diameter flange and capable of sliding like a piston in the cylindrical bore of the draw-plate.

This invention also relates to methods of lubrication adapted to the drawing operations described above and enabling this process to be carried out.

The invention also relates to a process for shaping tubular parts in accordance with those described and characterized in that one part by weight of crystalline graphite'and two parts by weight of oil are used for lubrieating purposes.

According to one feature of the invention, linseed oil is used for work on hot metal operated at more than 500 centigrade.

According to another feature of the invention, a mineral quenching oil is used for work on hot metal operated at less than 500 centigrade.

A machine in accordance with the invention is shown by way of example in the accompanying drawing, in which:

Figure 1 is an axial section view of the machine in its starting position: I

Figure 2 is an axial section view of this machine the first workingstage: J

.Figure 3 is an axial section View of this machine after the second working stage.

after Figure 4 is an axial section view of the machine when the finished case reaches the ejection stage.

Figure is a section view, on a larger scale, of the female part.

Figure 6 is a diagrammatic view of the machine assembly.

Figures 7 and 8 are section and plane views of the extracting device.

The machine illustrated in-Figures l to 4 comprises the following essential parts:

(a) An upper press cylinder fixed in the frame 1 of a press.

This upper cylinder 2 is fitted with a collar 3 which presses on a bearer 4 in the shape of a ring inserted in the frame 1.

A flange 5 with a tapped collar 6 and shoulder 7 presses by this shoulder against the collar 3 of the upper cylinder 2. The flange 5 is fitted with holes through which gudgeons 8 pass which are screwed into the frame 1. Nuts 9 screwed on to these gudgeons 8 press on the flange 5, which, through the intermediary of the shoulder 7, tightens the collar 3 of the cylinder in the bearer 4 and ensures that the cylinder 2 is securely fixed in the frame 1.

The upper cylinder 2 is arranged vertically and its axis XX is the axis of the machine or the working axis.

At its upper part, the cylinder 2 is formed by a movable end 10 engaged in a sliding manner in the bore of this cylinder 2. This end 10 comprises, on the internal side, a peripheric seating in which watertight packing 11 is placed in U-shaped section. This end 10 is pierced by an axial hole 12 and is integral, through the intermediary of a fluid inlet nozzle 13, with a cap 14 screwed on the external thread of the cylinder 2.

By screwing down or unscrewing this cap 14 the position of the end is regulated in the cylinder 2.

At its lower part, the cylinder 2 comprises an internal shoulder 15 forming an end in which the rod of the piston which will be described further on, can slide freely.

This shoulder is pierced by a radial channel 30 prolonged by a fluid inlet nozzle 31.

The tightness between this rod and this end is ensured by a washer 16 of U-shaped section placed in a shoulder seating 15 on the external side.

(b) A draw-plate holder case 17 of a general tubular shape comprising an upper part in the form of a sleeve 18 engaged on the lower part of the cylinder 2, and screwed by external threading in a tapping in the collar 6 of the flange 5.

The bearing 18 in the form of a sleeve comprises internal shoulders 19-21. The shoulder 19 presses on a washer 20 maintaining the washer 16 in its seating.

The shoulder 21 presses on an annular part 22 with a seating on the internal side for a U-shaped washer 23 applied against the piston rod. The annular part 22 presses against the washer 20 through the intermediary of a ring 24 pierced by two radially opposed holes 2526. This ring 24 makes an annular cooling chamber 27 round the piston rod.

The sleeve 18 is pierced with two diametral channels 2829 facing the opposite holes 2526 of the ring 24.

The case 17 has a ring 32 at its lower part with a square section fitted with an externally threaded hearing 33.

Internally, the ring 32 has two bores of different diameters 34-35 exactly centered on the axis XX and a flat shoulder 36 connecting these two bores and exactly perpendicular to this axis XX.

The case 17 is supplied with longitudinal ports between the upper sleeve 18 and the lower ring 32, these ports enabling the work to be inspected from the exterior, which is being executed by the machine, and limit the heat transmission by conductivity between the draw-plate and the press cylinder.

(c) A draw-plate or die 37 (Figure fixed on the lower ring 32 of the draw-plate holder case.

This draw-plate 37 of general tubular shape has two smooth bearings 3839 of difierent diameters at its upper part, and a flat shoulder 40 (Fig. 2) corresponding to the bores 34-35 and the shoulder 36 of the ring 32.

This draw-plate thus engages by its bearings and shoulders in the corresponding part of the ring 32. It is fixed on this ring 32 by a washer engaged around this drawplate 37, screwed on the externally threaded bearing 33 of this ring, and pressing by the internal shoulder on a corresponding external shoulder 43 of the draw-plate 37.

Internally, the draw-plate 37 has a working surface comprising from bottom to top: a widely open conical surface 44, a cylindrical bore 45 of a certain length and diameter D, a cylindrical bore 46 of shorter length and diameter D slightly less than the diameter D, a large radius clearance 47.

The bearing 40 of the draw-plate must be absolutely perpendicular to the axis of this draw-plate, so that the bores 45 and 46 are accurately centered on the Working axis XX.

Around the draw-plate 37 is a heat generator formed, for example, by an electric resistance 48 of annular shape.

(d) A drawing needle 49 whose lower end is slightly cone-shaped and presents the shape to be given to the interior of the case.

In the case of the example illustrated, this needle has rounded edges 500 and an axial depression 51 at its lower part.

The needle 49 is screwed by its upper part to the rod in a press piston 50 sliding in the upper press cylinder 2.

The rod of the needle 49 is of cylindrical shape and slides tightly in the watertight packing 16-23 of the cylinder 2 and the case 17. The diameter D of this rod is slightly less than the diameter D of the bore 46 of the draw-plate.

The press piston 500 has annular seatings 51-52 on both its surfaces in which U-shaped watertight packing 5354 is placed.

(2) A rammer 55 centered on the working axis XX, and integral with a press piston 56 similar to the upper piston 500. This lower piston 56 moves in a lower press cylinder 57 similar to the upper press cylinder 2, this lower cylinder being fixed to the common frame 1 of the press (Fig. 6).

The rammer 55 has a cylindrical rod 55 terminating at its upper part in a flange 58 of D diameter slightly greater than the D diameter and slightly less than the D diameter of the bore 45 of the draw-plate, so as to be able to slide with slight friction in this bore 45. (Fig. 5).

The machine described above operates in the following manner:

(I) Placing in the working p0siti0n(Fig. 1).The needle 49 is in its high position, the piston 500 pushing against the movable end of the cylinder 2, adjusted in a suitafie position by screwing down or unscrewing the cap In this position, the point of the needle is engaged in the bore 45 of the draw-plate.

The rammer 55 is in its low position. The starting part is placed on this rammer 55, this part being a cylindrical piece of bar or billet 60, whose diameter is approximately that of the case to be produced.

The billet 60 is previously heated and coated with graphited oil.

(2) Drawing the case-(Fig. 2).The driving fluid is injected into the lower part of the lower cylinder 57, the lower piston 56 rises at the same time as the rammer 55 holding the billett 60.

' This billet is pushed into the draw-plate 37 by the ralmmer 55 which engages in this draw-plate behind this bi let.

The billet 60 is crushed on the point of the needle whose shape it adopts in relief.

The movement of the rammer 55 continues upwards, the flange 58 of this rammer forms a piston in the bore 45 of the draw-plate which forms the cylinder, and the metal of the billet 60 is drawn upwards by the annular space 61 existing between the needle 49 and the bore 46 of the draw-plate.

At the end of the upward stroke of the rammer 55, the rough form 62 of a case is obtained, covering the point of the needle 49 and taking on the shape of the latter.

(3) Drawing the rough form of the case-{Figure 3).-By introducing the driving fluid into the upper part of the lower cylinder 57 and opening the exhaust of the lower part of this cylinder, the piston is moved downwards 56 and the rammer 55 also, which then disengages the rough form 62 of the case.

The driving fluid is then injected through the nozzle 13 into the upper part of the upper cylinder 2, which causes the piston 500 and the needle 49 to move downwards. This needle 49 lowers as far as the position shown in Figure 3, its rod sliding in the bore 46 of the draw-plate 37.

In this movement, the cylindrical part of the rough part 62 of the case is drawn between the cone-shaped point of the needle 49, which acts as a chuck, and the bore 46 of small diameter, which acts as a drawing collar-plate.

At the end of the down stroke of the needle 49, the case 63 has an external cylindrical form of D diameter and an internal form corresponding to the shape of the point of the needle 49.

This case covers the point of this needle 49 which projects downwards through the draw-plate 38 (Fig. 3).

(4) Extraction of the case-(Fig. 4).-A U -shaped extractor 64 (Figs. 7 and 8) and whose internal diameter is slightly greater than the D diameter of the rod of the needle 49 is engaged on this rod between the draw-plate 37 and the case 63.

The driving fluid is then admitted to the lower part of the cylinder 2 to move the piston 500 and the needle 49 upwards. The edge of the case 63 pushes against the extractor 64 and the case is held thus while the needle continues its upward movement.

The machine thus returns to its starting position and is ready for a new operation.

The driving fluid admitted or discharged by the nozzles 13-31 of the cylinder 2 can be a liquid such as oil or a gas such as compressed air.

The inlet and exhaust control is efiected by means of distributors of known types.

Theinlet and discharge control of the driving fluid in each cylinder can be ettected so as to obtain: a rapid stroke when the effort made is weak; a slower stroke when the working elfort is made.

Thus, the rammer 55-58 will bring the billet 60 rapidly against the point of the needle 49 then move slowly and according to a reduced stroke to draw the metal of the billet 60.

The disengaging stroke of the rammer 55-58 outside the draw-plate will take place in a rapid manner.

The up-stroke of the needle through the draw-plate 37 and during which the extraction of the finished case takes place, does not require force and occurs rapidly.

Finally, the down-stroke of the needle through the die for producing drawing of the rough part, requires much less work than the drawing of the rough part by the rammer. The upper cylinder 2 can have a much smaller section than that of the lower cylinder 57 and the down stroke of the needle 49 can be made much more rapidly than the up-stroke of the rammer 55.

In the annular space 27 surrounding the rod of the needle 49 cooling water is circulated arriving by one of the channels 2829 and leaving by the other. The rod of this needle is thus cooled, which reduces the heat transmitted by conductivity from the point of this needle 49 to the piston 500, the cylinder 2 and the watertight packing.

In the machine described above, the needle 49 is advantageously made of one piece, which enables very accurate centering of this needle 49 in the draw-plate.

The cases obtained also have cylindrical walls of very even thickness.

The process claimed can also be used for certain metals, such as aluminum, without external heating of the draw-plate 37. The water circulation in the annular space 27 can nevertheless be maintained to prevent the heat given ofi by the metal worked being transmitted to the watertight packing.

In this case, spray lubrication is provided for over the draw-plate 37.

The process applies to all metals or alloys capable of being manipulated hot or cold, such as brass, copper, aluminium bronze, mild or semi-hard steel, aluminium, light alloys, magnesium alloys, etc.

According to the present'invention, a mixture is used in connection with the above-mentioned processes and for hot work on brass, steel and in a general manner on all metals worked at more than 500 centigrade, this Well-stirred mixture being composed of:

Parts by weight Linseed oil 2 Crystalline graphite 1 For hot working on aluminium, light alloys and in a general manner on all metals working at less than 500 centigrade, a well-stirred mixture is used consisting of:

Parts by weight Mineral quenching oil 2 Crystalline graphite l The mineral quenching oil should preferably contain 10 to 20% of colza oil.

Shaping work can be facilitated by an addition of 10% by weight of linseed oil to mineral oil mixed with crystalline graphite.

In the case of the cold working of a metal such as aluminium, the starting billet is coated with a viscous mineral oil such as that normally used for greasing the gears of the back axle of automobiles.

An oil should be selected which adheres well to the metal so as to stand up to the washing produced by the running of the cooling water required, as described in this principal patent.

The various means of lubrication described above enable the shaping operations to be carried out which are described in the principal patent, without the risk of tearing or folding the metal.

With regard to known processes, this process claims the following technical advantages:

(1) The two stages of shaping the rough part from the billet and drawing this rough part are carried out in the same female part 37. Owing to this fact, the machine is simpler than known machines.

(2) The female part has no internal shoulder capable of retaining scraps of metal and requiring to be cleaned after each operation.

(3) The billet 60 used as a starting part appreciably has the diameter of the finished case and can be cut from a bar of relatively small section. In this manner, losses of metal by sawing or cutting the bar into lengths are reduced.

(4) The process claimed enables cases to be obtained of cylindrical external shape, but with a tapered internal form.

Furthermore, the end of this case can have any relief required, either outside or inside. It only requires a corresponding hollow to be made on the surface of the end of the needle 49 or the surface of the end of the rammer 5558.

(5) The first stage takes place by crushing the billet on 7 the end of the needle 49, i. e., by compressing and fewing the metal of the billet 60 by the rammer 55 -58.

The second stage is obtained by drawing the rough part whose end is pushed by the needle 49 and whose edges are pinched in the drawing port formed between the female part 37 and the tapered surface of this needle.

In both stages the metal is manipulated parallel to the direction of the movement of the movable part and in the same direction as that of this movement, which produces perfectly strong cylindrical walls.

(6) The process claimed combining an operating of shaping and an operation of drawing enables a tubular part to be obtained in a single press operation whose walls are thinner than those of the part which could be obtained by a single drawing operation.

What I claim is:

1. In a machine for the shaping of tubular elements having a bottom, such as cases, from a solid starting billet, a frame, an upper cylinder mounted on said frame, a lower cylinder opposite and coaxial with said upper cylinder, mounted on said frame, an upper piston sliding in said upper cylinder, an axial member integral with said upper press piston and consisting of a needle having a cylindrical stem and an end portion which is slightly conical, a female member of annular shape secured on said frame in the axis of the upper and lower cylinders, said female member having a cylindrical bore and a constricted annular part of smaller diameter than that of the cylindrical bore on the side of the axial member and of greater diameter than the diameter of the axial member to permit the latter to slide past said constricted part, a lower press piston sliding in the lower cylinder, and a ram secured on said lower press piston and coaxial with said female member and with said axial member.

2. In a machine for the shaping of tubular elements having a bottom, such as cases, from a solid starting billet, a frame, an upper cylinder mounted on said frame, a lower cylinder opposite to and coaxial with said upper 8 cylinder, mounted on said frame, an upper press piston sliding in said upper cylinder, an axial member integral with said upper press piston and consisting of a needle with a cylindrical stem, the end portion of which is slightly conical, a female member of annular shape secured on said frame in the axis of said upper and lower cylinders, and said female member having a cylindrical bore and a constricted annular part of smaller diameter than that of said cylindrical bore on the side of the axial member and of greater diameter than the diameter of the axial member to permit the latter to slide past said constricted part, a lower press piston sliding in said lower cylinder, and a ram secured on said lower press piston and coaxial with said female member and with said axial member, said ram consisting of a cylindrical stem terminating at its upper portion in a flange capable of sliding like a piston in the cylindrical bore of said female member.

References Cited in the file of this patent UNITED STATES PATENTS 560,480 Deming May 19, 1896 851,262 Tatum Apr. 23, 1907 1,151,222 Scrimgeour Aug. 24, 1915 1,474,066 Brown Nov. 13, 1923 1,684,102 Leustig Sept. 11, 1928 2,063,562 Sparks Dec. 8, 1936 2,183,637 Biginelli Dec. 19, 1939 2,237,993 Korbuly Apr. 8, 1941 2,339,959 Stadlin Jan. 25, 1944 2,407,855 Stephens Sept. 17, 1946 2,596,552 Heimann May 13, 1952 V FOREIGN PATENTS 212,258 Germany Dec. 24, 1907 443,060 Germany Dec. 17, 1922 524,146 Great Britain of 1940 851,629 France of 1940

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