US1839421A - Extrusion press - Google Patents

Description

F. SINGER EX'I'RUS I 0N PRES S Jan. 5, 1932.

Filed Sept. 29, 1930 3 Sheets-Sheet INVENTOR -llEi.

wnuesss a w @w F. SINGER EXTRUSION PRESS Jan. 5, 1932.

Filed Sept. 29, 1930 3 Sheets-Sheet 2 INV ENTOR Qwmrh 3 Sheets-Sheet 3 3 3. 7 A 10 2 j d h/iii, d r A z z??? w w m 4 /MN /fl///$ 1 9 Filed Sept. 29, 1930 ufl jaln- 1932.

. J7 a 9 2/ /Mw//// 6 i WITNESSES Patented Jan. 5, 1932 PATENT OFFICE FRITZ SINGER, OF NUREMBERG, GERMANY nxrnusion PRESS Application filed September 29, 1930, Serial No. 485,278, and in Germany April 2, 1928.

My invention pertains to extrusion presses, and especially to extrusion presses of the character in which the force for the extruding operation is applied by a crank, eccentric or similar mechanical means.

Extrusion presses, because of the high pressure forces dealt with, are naturally heavy, and it is very desirable that this weight be minimized as far as is possible. The weight of such presses, and especially those in which the power is appliedby a crank, increases with the length of the stroke, and therefore, in order to minimize weight, it is desirable that the stroke be kept as short as possible consistently with meeting other conditions satisfactorily. In crank-actuated presses this can only be done by utilizing the greatest part possible of the stroke for the actual extruding operation. However, in crank-actuated presses as heretofore constructed, it has been found difiicult thus to use a large part of the stroke for the actual extruding.

For instance there must be space enough between the tools, prior to the extruding operation, to permit the billet to be inserted in its container. This, of. itself, requires that the crank stroke be about twice that which would be necessary forthe vactual extruding. Moreover, when tubes are to be extruded,the

piercing stroke of the mandrel must be added, sojthat the required stroke of the crank becomes, about three times that necessary for the extruding operation itself. q

It is possible to reduce the lengthof the crank stroke by making the billet container, or the extruding punch with its mandrel, removable, laterally slidable or the like, soas to obviatethe excess of crank stroke required for permitting insertion of the billet into the container. However, complications and some disadvantages attend such constructions, and, in any event, when tubes are to beproduced, they still leave the crank stroke about twice what isnecessary for the extruding operation. For the above reasons the crank stroke, in such presses heretofore produced, has been relatively-long, as compared with the actual extruding movement,

and the weight of the press has correspondingly increased.

The total crank stroke can be used for actual extrudin where the billet temperatures and moulding degrees are comparativelv low. However, in the employment of crank-actuated extrusion presses the billet temperatures and moulding degrees are usually high. With these high billet temperatures and moulding degrees it has been found that a certain minimum speed is desirable in initiating the flow of the metal, in order to prevent the part first extruded,'such as the leading end of a thin-walled tube, from sticking fast in the aperture of the die. As the first part of a crank stroke is quite slow, it is hardly satisfactory to employ the total crank stroke for actual extruding where the billet stroke of the mechanical means can be employed for the actual extruding operation. It is another object of the invention to combine in .an extrusion press the advantages of mechanical and hydraulic actuating means.

r In carrying my invention into efiect, I actuate, after insertion of the billet into the container, one of the extruding tools by hydraulic means to bring it into operative association with the other extruding tool, which latter (being, in the particular embodiment of my invention to be described below, the extruding punch) is then mechanically actuated to extrude the billet. In this way I am enabled to utilize the whole mechanical stroke, or as much thereof as I ma desire. Furthermore, the hydraulic means urnishes a simple way of obtainin one part of the press movement, and, in addition, it makes it possible to obtain the advantages of hydraulic safety devices.

By. way of exainple,I have described an extrusion press constructed in. accordance tends downward prior to the insertion of a billet into the con-' tainer;

Fig. 2 is a similar view, showing the parts, however, in the position in which the billet container has been raised with respect to the punch, pushing the latter upward and causing the billet to be pierced by the mandrel;

Fig. 3 is a similar view, with the hydraulic systemomitted, showing the parts after the punch has been forced downward to extrude the billet; and

Fig. 4 is a view similar to Fig. 3 but showing the parts as having returned to their original position, ready for the severence of the billet residue from the extruded article.

In the particular form of extrusion press embodying my invention chosen for illustration, the extrusion tools move vertically and it is the punch which is mechanically actuated. Such press comprises a frame 1 which carries, at the lower part thereof, a fixed tab1e'2. Upon such table is secured a vertically disposed hydraulic cylinder 3 in which operates a piston 4. The latter is formed with a stem 5 which is suitably guided in the cylinder and is formed with a central bore 6 to accommodate the extruded article, in this case a tube. A pipe 7 provides for ingress of fluid under pressure to the interior of the cylinder, 50 that, when such fluid is admitted to the cylinder, the piston will be caused to rise in the latter until stopped by the engagement of a shoulder 8 with which it is provided with an abutment'ring 9 secured to the top of the cylinder. Upon the top of the piston is secured the billet container 10, which carries, in the lower end thereof, the female die 11, the aperture of which makes alignment with the bore 6 of the piston.

Slidably mounted, in suitable ways. in the upper part of the press frame 1 is a punch carrier 12 which'is made in the form of a hollow cylinder, having the lower end thereof closed by a wall 13. The punch carrier has extending downwardly therefrom, in alignment with the billet container 10, a punch 14, such punch being secured to the under side of the wall 13. The punch and the wall 13 are. bored for the passage therethrough of the mandrel 15 which is secured to, and exfrom, a mandrel carrier 16 which takes the formof a piston slidably mounted in the punch carrier. The relative movement between the punch carrier and mandrel carrier is limited, at the'bottom, by

the wall 13 and, at the top, by a ring 17 secured to the upper end of the punch carrier. The mandrel carrier is connected by means of a ball and socket joint 18 with one end of a connecting rod 19, the other end of which shaft 20 isnow set in In the position of the parts shown in Fig. 1 r

a heated billet a is inserted in the container 10 and fluid under pressure is then admitted to the interior of the cylinder 3. The result is that the piston 4 moves upwardly in the cylinder, carrying the billet into engagement with the lower end of the punch 14. The punch carrier will thereafter move upward with the billet, such upward movement being resisted only by the weight of the punch and its carrier. The mandrel carrier 16, however, is held stationary by the connecting rod 19, the crank shaft 20 not beingjn motion at the time, with the result that the billet, as it continues to move upward, is pierced by the mandrel 15. This piercing of the billet is completed by the time that the upward movement of the piston 4 is stopped byreason of the engagement of its shoulder 8 with the ring 9 (Fig. 2).

By the time the upward movement of the billet container 10 has been thus completed, the punch carrier will have been raised until its wall 13 is within a short distance of the bottom of the mandrel carrier 16. The crank motion. This may be done by hand, or, in any one of a number of ways well understood in the art, it may be efl'ected automatically upon the billet carrier reaching the upward limit of its movement. When the crank shaft starts torotate. it will cause a downward movement of the mandrel carrier 16. The first part of this movement is ineffective, the mandrel carrier traversing the small space (Fig. 2) left between itself and the wall 13 of the punch carrier. When the mandrel carrier engages the wall- 13, however, the punch carrier is caused to participate in its downward movement, whereby the punch is forced downward in the billet container so as to extrude the billet around the mandrel to produce the tube b, the extrusion being complete by the time that the crank 21. has reached its bottom dead center (Fig. 3). Thereafter the crank 21 completes its rotation and at the same time the pressure fluid is permitted to escape from the cylinder 3, so that the piston 4 descends of its ownv weight. This brings the parts to the position shown in Fig. 4. The billet residue is then sheared off from the tube by means of a suitable tool such as that indicated at 23, and such residuewis removed from the container. Another billet and the process repeated.

can then be inserted part of such stroke, such first'part being oc-.

cupied by the taking up of the space (Fig. 2) between the mandrel carrier and the Wall 13 of the punch carrier. Thus the extruding movement of the punch carrier will be started at a-material speed, and it is to be notedthat this starting speed can be determined, in accordance with requirements, by varying the distance left between the mandrel carrier and the punch carrier when the billet container has reached its uppermost position.

The pressdescribed is arranged vertically and the weight of the punch carrier and as sociated parts, and also of the piston 4 and associatedparts, is suflicient to move and urge them downward as required. The press might be arranged horizontally, in which case suitable instrumentalities, mechanical, hydraulic or the like, could be employed for urging these members in the required directions.

The hydraulic system selected for illustration comprises a pump 24 connected by a tube 25 and through a suitable check valve 26 with a valve 27, the latter being also connected with the inlet tube 7, above referred to, and a waste pipe 28. Valve plunger 29 is adapted tobe operated by a hand lever 30 so as to move between a position in which the inlet tube7 is in communication with the waste pipe 28 (Fig. 1) and a position inwhich said inlet tube is in communication with the supply tube 25 (Fig. 2). Between the pipe 24 and the check valve 26 a tube 31 branches from the tube25 and communicates through a check valve 32, and through a safety valve 33, with the interior of the low pressure cylinder 34 of a multiplier 35. The low pressure piston 36 of the multiplier is rigidly connected with the high pressure piston 37 working in the high pressure cylinder v38,

Y which latter,'through a tube 39 communicates with the inlet tube 7.

I In starting the press, the hand lever 30 is moved from the position shown in Fig. l to the position shown in Fig. 2 thereby admitting fluid to the cylinder 3, with the results described above. When the piston 4 has reached. its upperposition it will ,be supported therein, to withstand the extrusion pressure, by the fluid pressure applied through the tube 39 from the multiplier 35. Moreover, should a pressure accidentally be developed,by the presence of a cool billet, or for some other reason,beyond that which the press is designed to withstand, the safety valve 33. being designed to that end would open and allow the piston 4 to descen For lifting the piston 4, and also for piercing the billet, comparatively slight hydraulic pressure forces are sufiicient, so that an expensive hydraulic plant is not needed, whilst at the same time, the parts can be made to move at relatively high speed. Moreover, there is a substantial advantage in employing hydraulic means for moving one of the extruding'tools in that it can also be used for maintaining such tool in position to withstand the extruding pressure, and at the same time provides a simple and eflicient safety device.

otherwise applied, as, for instance, in the tube leading from the pump.

In the particular form' of the press described above, the billet container and female die are actuated by hydraulic means while the punch is actuated by mechanical means. However, I contemplate that in other constructions of press the punch might be moved by hydraulic means and the container and female die moved by mechanical means to perform the extruding operation. Such and other embodiments of my invention, as well as changes which. may bemade in the particular embodiment which has been described and shown, are within the scope of my invention as defined in the appended claims.

I claim:

1. In an extrusion press, two members mounted for reciprocating movement in line with each other, a male die associated with In some circumstances, the multiplier may be omitted and a safety valve one of said members, a billetand die-carrier associated with the other member, hydraulic driving means for operating one of said members to bring it into the extruding position, and mechanical driving means for operating the other member to extrude the billet.

2.. In an extrusion press, two members mounted for reciprocating movement in line with each other, a male die associated with one of said members, a billetand die-carrier associated with the other member, hydraulic driving means for operating one of said members to bring it into the extruding position, and crank-actuated driving means for opcrating the other member to extrude the billet.

3. In an extrusion press, two members mounted for reciprocating movement in line with each other, a male die associated with one of said members, a billetand die-carrier associated withthe other member, hydraulic driving means for operating one of said members to bring it into the extruding position, mechanical driving means for operating the other member to extrude the billet, and a safety valve connected with 'the hydraulic cylinder.

. 4. In an extrusion press for producing tubes, two members mounted for reciprocating movement in line Y with- 9&1 1- other, a

punch and a mandrel associatedwith oneof said members, a billetand die-carrier associated with the other member, hydraulic driving means for operating one of said members to bring it into the extrudin position, whereby the billet is simultaneous y pierced, and mechanical driving means for operating the other member to extrude the billet.

5. In an extrusion press for producing tubes, two members mounted forreciprocating movement in line with each other, a punch and a mandrel associated with one of said members, a billetand die-carrier assoeiated with the other member, hydraulic driv in means for operating one of said members to ring it into the extruding position, whereby the billet is simultaneously pierced, mechanical driving means for operating the other member to extrude the billet and a safety valve connected with the hydraulic cylinder.

6. In an extrusionpress, a reciprocating member, crank-actuated means for operating said member and for effecting the operation of extruding the billet, a male die arranged on said member, a piston, a billetand die-carrier mounted thereon, and a hydraulic cylinder adapted to operate said'piston in line with said member and adapted to bring said billet and die-carrier into the extruding position. i

7. In an extrusion press, a reciprocating member, crank-actuated means for operating said member and for effecting the operation of extruding the billet, a male die arranged on said member, a piston, a billetand die-carrier mounted thereon, a hydraulic cylinder adapted to operate said piston in line with said member and adapted to bring said billetand die-carrier into the extruding position, and a safety valve connected with the "hydraulic cylinder.

8. In an extrusion press for producing tubes, a reciprocating member, crank-actuated means for operating said member and for effecting the operation of extruding the billet, a punch and a mandrel associated with said member, a piston, a billetand die-carrier mounted thereon,'. and a hydraulic cylinder adapted to operate said piston in line with said member and adapted to bring said billetand die-carrier into the extruding position, whereby the billet is simultaneously pierced.

9. In an extrusion press for producing tubes, a reciprocating member, crank-actuated means, for operating said member and for effecting the operation of extruding the billet, a punch and a mandrel associated with said member, a piston, a billetand diecarrier mounted thereon, a hydraulic cylinder adapted to operate said piston in line with said member and adapted to bring said billetand die-carrier into the extruding position, whereby the billet is simultaneously pierced, and a safety valve connected with the hydraulic cylinder.

10. An extrusion ress for producing tubes, comprising a ho low punch, a member for supporting the same, a second member slidably associated with said first-named member, a piercing mandrel passing through said punch and supported by said second named member, means for limiting the sliding movement of said members with respect to each other, a billetand diecarrier mov able in line with said punch and mandrel, hydraulic means for moving'said carrier towards said punch and mandrel, means tending to move said first-named member with respect to said second-named member and towards said carrier, and crank-actuated means for moving said second-named member towards said carrier.

11. An extrusion press .for producing tubes, comprising a hollow punch, a member for supporting the same, a second member slidably associated with said first-named member, a piercing mandrel passing through said punch and supported by said secondnamed member, means for limiting the sliding movement of said members with respect to each other, a billetand die-carrier movable in line with said punch and mandrel, hydraulic means for moving said carrier towards said punch and mandrel, means tendingto move said first-named member with respect to said second-named member and towards said carrier, crank-actuated means for moving said second-named member towards said carrier, and means for limiting the movement of said carrier to accord with the scope of relative movement between said firstand second-named members.

i 12. In an extrusion press, two members mounted for reciprocating movement in line with each other, a male die associated with one of said members, a billetand die-carrier associated with the other member, means for moving one of said members towards the other to bring the moving member into position for the extruding operation, and driving means for operating the other member to extrude the billet.

In testimony whereof, I hereunto sign my name:

FRITZ SINGER.

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