US3827273A

US3827273A - Shearing device for unextruded butts in an indirect metal extrusion machine

Info

Publication number: US3827273A
Application number: US00302506A
Authority: US
Inventors: R Tamura; S Kishino; T Abe
Original assignee: Japan Steel Works Ltd
Current assignee: Japan Steel Works Ltd
Priority date: 1971-11-25
Filing date: 1972-10-31
Publication date: 1974-08-06
Anticipated expiration: 1991-08-06
Also published as: JPS5139187B2; JPS4857870A

Abstract

In an indirect metal extrusion machine butts of a billet left on the end surface of a die are sheared off the die by a cutter arranged on a frame over the die when the die is retracted after the extrusion of the billet is completed.

Description

United States Patent [191 Kishinn et a1.

[ SHEARING DEVICE FOR UNEXTRUDED BUTTS IN AN INDHRECT METAL EXTRUSKON MACHINE [75] Inventors: Shunji Kishino; Takahiro Abe, both of Muroran; Reishi Tamara, Noboribetsu, all of Japan [73] Assignee: Japan Steel Works Ltd., Tokyo,

Japan 22 Filed: 0ct.31, 1972 211 App]. No.: 302,506

[30] Foreign Application Priority Data Nov. 25, 1971 Japan 1. 46-94134 [52] US. Cl. 72/255, 72/462 [51] Int. Cl. B2lc 23/00 [58] Field of Search 72/255, 254, 467, 462

[in 3,827,273 [451 Aug. 6, 1974 [56] References Cited UNITED STATES PATENTS 2,456,856 12/1948 Bath 72/462 3,220,237 1 H1965 Govan 72/255 3,357,226 12/1967 Snell 72/253 3,407,642 10/ 1 968 3,522,721 8/1970 Whiting .11. 72/255 Primary Examiner-Charles W. Lanham Assistant Examiner--Robert M. Rogers Attorney, Agent, or Firm-Wenderoth, Lind & Ponack [5 7] ABSTRACT In an indirect metal extrusion machine butts of a billet left on the end surface of a die are sheared off the die by a cutter arranged on a frame over the die when the die is retracted after the extrusion of the billet is completed.

1 Claim, 5 Drawing Figures PATENTEU RUB 51974 SHEU 1 (IF 2 I PRIOR ART FIG. 2

PRIOR ART SHEARING DEVICE FOR UNEXTRUDED BUTTS IN AN INDIRECT METAL EXTRUSION MACHINE BACKGROUND OF THE INVENTION This invention relates to an indirect metal extrusion machine, and more particularly to a shearing device which can cut off unextruded butts with safety and reliability at the completion of extrusion when a metal is extruded by indirect extrusion.

Hitherto when a metal is extruded by indirect extrusion, a die for extrusion is fitted on the end of a long hollow stem and the unextruded butt which is stuck to the die must be removed at the completion of extrusion.

FIG. 1 shows a die mounting device in which a die 1 is simply inserted in the axial direction as an example of conventional method of removing butts.

In this case the extruded product is cut off with a shearing tool 4 between the die 1 and the stem 2 after the die 1 is slightly moved away from stem 2 to permit the shearing operation.

By this method, however, in order to remove the unextruded butt stuck to the die 1, the die 1 must be taken out of the extruding machine and the butt must be separator with a specially provided butt separater, and thereafter the die must be remounted on the stem manually or mechanically for the next succeeding extrusion.

To mount the die in this way at every operation, much labor is needed in the case of manual operation, causing a poor productivity, and for mechanical operation a die setting device must be provided to operate a long arm having a die grip device from outside the machine. In addition a butt separater is needed and these requirement cause disadvantages in cost and maintenance of the apparatus.

In FIG. 2 showing another example of removing method, because the die remains fixed to the stem, shearing is executed inside the machine without exchange of dies every time.

In this case the butt shear 6 is mounted on an upper tie-rod 7 of the machine and the shearing tool 4a cuts off the butt with a high efficiency. But the reaction force from the shearing tool 4a acts at the end of the long hollow stem and the center of the tie-rod, causing a big bending moment which is unfavorable from the standpoint of strength of the machine.

One of the reasons why the indirect extruding machine has not been used in general, although the indirect extruding method has more advantages in principle than the direct method commonly used, is the process of cutting the butt when the die is at the extruding position or supported on the stem in the center space of the machine.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the disadvantages of conventional types of indirect extrusion machines and to provide a butt shearing device which will make it possible to cut off the butt stuck on the die fixed at the end of a long stem reliably and with a reasonably simple device. The shearing device of the present invention is preferably composed of a butt cutting means slidably mounted on a platen of an indirect metal cutting machine and a die supporting means which cooperates with the cutting means.

BRIEF DESCRIPTION OF THE DRAWINGS This and other objects of the present invention will become more apparent to those skilled in the art when considered in reference to the following detailed description in the light of the accompanying drawings, wherein:

FIG. 1 is a sectional view of an example of a conventional butt removing method;

FIG. 2 is a sectional view of another example of a conventional butt removing method;

FIG. 3 is a view in section of an embodiment of the device according to the present invention at the completion of extrusion;

FIG. 4 shows an enlarged side view of the device shown in FIG. 3; and

FIG. 5 shows a view in vertical section of the device shown in FIGS. 3 and 4 in the position for shearing a butt.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 3 which shows an embodiment of the device according to the present invention, partly in section, at the time of completion of extrusion, the die 11 is fixed to the stem 12 and the extruded product 13 is extruded through the hollow of the stem 12.

The reference numeral 14 represents a shearing tool for the unextruded butt stuck to the die 11 and is fixed to a butt shearing head 16.

The shearing head is mounted so as to be freely movable up and down on a frame 17 fixed to the platen 24.

The reference numeral 18 represents a stem holder, holding the stem 12 on the end surface thereof and the stem 12 is fixed to the stem holder by a stem clamp 19.

As shown in FIG. 4, a pair of die holders 20 is mounted on the frame 17 and an upper horizontally movable pressure bearing plate 21 with a lower tapered edge is set beneath the die holder 20 and another pressure bearing plate 22 with an upper tapered edge complementary to the tapered edge on upper plate 21 and engaged therewith is fixed on the frame 17.

The movable bearing plate 21 can slide by means of adjust bolts 23 on the frame 17 in order to adjusting the height of the die holder 20.

As shown in FIG. 3, cutting line A of the shearing tool 14 must be in such a position as to traverse the stem 12.

The movement of the stem 12 in the axial direction thereof is executed by opening and closing of a gate (not shown) mounted on the platen 24 generally called a gate lock mechanism.

In this embodiment, the frame 17 for the butt shearing head has a unitary body construction, in which the die holding device is set, but the die holding device can be mounted on the platen 24 as separate pieces.

It is most desirable that the position of butt shearing head 16 coincide with the position for the case of direct extrusion.

Following is an explanation of the butt shearing operation with the device according to the invention.

The die 11 and the stem 12 are moved to the position of cutting line A for the shearing tool 14 of the butt shearing head 16 on the frame 17 mounted on the platen 24 shown in FIG. 5 from the position at the completion of extrusion shown in FIG. 3. At this position the die 11 is held and fixed around its outside by the die holder 20.

The shearing head 16 slides downward on the slide 17 and cuts off the butt with the shearing tool 14 at the position of cutting line A. During this operation, the reaction force on the shearing tool 14 is transmitted to the frame 17 by means of the

pressure bearing plates

21 and 22.

As above described, exchange of dies for every extrusion is not needed and the die setting device can be eliminated. Moreover structurally undesirable large bending moments do not occur on the long stem and the tie-rod.

As the position of butt shearing coincides with the position in case of direct extrusion and one butt shearing device can be used for both direct and indirect extrusion, the structure of the extruding machine can be simplified, giving another advantage.

While the invention has been shown and described with reference to a preferred embodiment thereof it will be apparent that other changes and modifications can be made in the present invention and therefore it is understood that all changes, equivalents, and modifications within the spirit and scope of the present invention are here meant to be included in the appended claims.

What is claimed is:

1. In an indirect metal extrusion machine having a platen and a die holding stern mounted in a stem holder and held therein by a stem clamp and movable through the platen in the direction of the length of the stem so that the die is projected from the platen, an improved butt shear means comprising a frame mounted directly on the platen above the stem, a butt shear slidably mounted on said frame for slidable movement across the end of the die when the stem is withdrawn into the platen, said frame extending down and around the stem, and an upper and lower die holder mounted in the portion of said frame which extends down around the stem and engaging the die for holding the die when the stem is withdrawn into the platen.

Claims

1. In an indirect metal extrusion machine having a platen and a die holding stem mounted in a stem holder and held therein by a stem clamp and movable through the platen in the direction of the length of the stem so that the die is projected from the platen, an improved butt shear means comprising a frame mounted directly on the platen above the stem, a butt shear slidably mounted on said frame for slidable movement across the end of the die when the stem is withdrawn into the platen, said frame extending down and around the stem, and an upper and lower die holder mounted in the portion of said frame which extends down around the stem and engaging the die for holding the die when the stem is withdrawn into the platen.