Title:
METHOD AND APPARATUS FOR PRESSING AND INDENTING A WORKPIECE
United States Patent 3768296
Abstract:
The disclosure of this invention relates to a method and/or apparatus for performing in a prescribed operational sequence a pressing and a nosing operation on a workpiece, such as, a metallic slab. The pressing operation is accomplished by a movable platen and punch carried thereby; whereas, the nosing operation is accomplished by a nosing tool secured to the platen and movable therewith. A piston cylinder assembly moves the nosing tool in guides relative to the platen, in which behind the tool there is adapted to be selectively inserted one or more filler pieces of varying thickness, the purpose of which is to be able to vary the penetration of the nosing tool in a manner that the working force of the nosing tool is transferred from the tool to the platen.
Application Number:
05/288639
Publication Date:
10/30/1973
Assignee:
Wean United, Inc. (Pittsburgh, PA)
Other Classes:
72/413, 72/473, 72/477, 100/295
International Classes:
B30B15/08; B30B15/00; (IPC1-7): B21D37/00
Field of Search:
72/377,477,478,413,473 100
Primary Examiner:
Herbst, Richard J.
Assistant Examiner:
Rogers, Robert M.
Claims:
1. In combination with a press for compacting metal workpieces and the like having at least one movable platen for displacing a punch associated therewith,
2. In combination with a press in accordance with claim 1:
3. In combination with a press according to claim 2:
4. In combination with a press in accordance with claim 3:
5. In combination with press in accordance with claim 4 wherein said two plates have different effective thicknesses so that the steps of penetration of the tool can be varied.
6. In combination with a press in accordance with claim 1:
7. In a method of performing the pressing and nosing operation on a workpiece by a combined press and nosing mechanism wherein said nosing mechanism is carried by, but movable relative to said press, the steps comprising:
8. In a method according to claim 7 wherein in said operative position of said nosing mechanism only a partial nosing is performed, the additional step of
Description:
In the formation of slabs out of the automotive scrap by a pressing or compacting operation preparatory to the hot rolling of the slabs by a rolling mill, it is desirable for at least certain sizes of the slabs to chamfer or taper the leading end so that the leading end of a slab will have a better opportunity to be unhesitatingly fed into the rolls of the mill.
It has been suggested when the nosing or tapering of the front end is to be accomplished before the slabs are heated for hot rolling, that the nosing be accomplished by a separate operation distinct from the pressing operation. This, of course, appreciably adds to the expense not only of the equipment, but also of labor and plant space.
It is, therefore, an object of the present invention to provide a method and/or apparatus for performing an indenting of a pressed workpiece as an adjunct to the pressing operation.
More particularly, it is the object of the present invention to provide a method and/or apparatus for performing a pressing operation to reduce the thickness of the workpiece to a predetermined dimension, associating an indetenting mechanism with the platen of the press in a manner that an indenting tool can be brought into operation after the pressing operation is completed to perform an indentation on the pressed workpiece.
A further object of the present invention is to provide in combination with a press having a movable platen to which a punch is secured for reducing the thickness of a workpiece to a predetermined dimension a nosing mechanism secured to said platen, said nosing mechanism including a tool having a workpiece penetrating surface at its one end which is arranged to serve as an extension of the working surface of said punch, means for moving said tool from a position where its working surface is behind the working surface of said punch to a position where at least a portion of the working surface of said tool extends beyond said punch, said tool having a load transmitting surface at its end opposite its working surface, and one or more filler members arranged to be selectively moved into and out of a load transmitting relationship between themselves and said tool and said platen.
These objects, as well as other novel features and advantages of the present invention, will be better appreciated when the following description is read along with the accompanying drawings of which:
FIG. 1 is an elevational schematic view of a press and a workpiece indenting mechanism of the present invention,
FIG. 2 is an enlarged view of a second position of the indenting mechanism shown in FIG. 1,
FIG. 3 is an enlarged view of the details of the construction of the indenting mechanism shown in FIGS. 1 and 2,
FIG. 4 is an end view of the indenting mechanism shown in FIG. 3, and
FIG. 5 is an enlarged view of the working surface of the indenting tool shown in the earlier figures.
In referring first to FIG. 1, there is shown in outline form an upright hydraulic press of a very well-known construction and in view of which only the major components need be specifically identified. Accordingly, the press includes two pairs of spaced upright tension members 10, two of which are only illustrated in FIG. 1, the members being tied together at their top and bottom by entablatures 11 and 12 secured to the members by nuts 13. Intermediate the entablatures 11 and 12 there is arranged a platen 15 which carries a punch 16, the platen and punch being moved towards and away from a stationary opposite punch 17 by an hydraulic piston cylinder assembly, not shown. FIG. 1 illustrates the platen 15 and punch 16 in their lowermost working positions and to the right, a portion of a pressed or compacted workpiece 20 which corresponds, it will be noted, in thickness to the illustrated opening between the elements 16 and 17.
Turning now to the construction of the indenting mechanism of the present invention, reference will be made to FIGS. 3, 4 and 5. This mechanism in the illustrated form comprises a nosing tool 21 made in the form of a rectangular plate having a lower inclined working surface 22 mounted relative to the working surface of the punch 16 so that in its working position the working surface 22 extends below the working surface of the punch 16. The tool is restrained and guided vertically by end guides 23 secured to the adjacent vertical surfaces of the punch 16. In addition, the tool is held against the punch 16 by space bolts 24, the tool having slots 25 permitting relative movement between the punch and tool, but restrained from moving away from the punch by a cross bar 28 arranged inside the nuts 29 of the bolt 24. The tool is moved vertically by a centrally arranged piston cylinder assembly 31 also carried by the punch 16; the stroke of the cylinder being sufficient to, on the one hand, raise the lowest portion of the surface 22 behind the working surface of the punch 16 and, on the other hand, to lower the surface 22 below the working surface of the punch sufficient to allow the tool to take at least two different depths of penetration.
A second part of the nosing tool consists of a mechanism for transferring the working load of the tool to the platen 15 and for varying the degree of penetration of the tool. This is accomplished by providing two independently slidable filler bars 33 and 34 which take the form of uniform thickness plates, but each of which has a different thickness. In the illustrated form the plate 33 has a thickness of 21/2 inches; whereas, the plate 34 has a thickness of 21/4 inches which allows the tool to have a first step penetration of 43/4 inches and a second step of 21/2 inches.
The plates themselves have flat contacting surfaces 36 that engage each other and, in addition, similar surfaces 37 and 38, respectively: the surface 37 contacting the top of the tool 21 and the surface 38 contacting the lower flat surface of the platen 15.
The filler bars 33 and 34, as shown in FIG. 4, are dovetailed at 41 and 42 in which the dovetail 41 allows the bar 33 to be supported by the platen 15 and the dovetail 42 allows the bar 34 to be supported by the bar 33. The dovetails, as shown in FIG. 3, extend almost the entire distance of the bars, but terminate before reaching the area above the tool 21. The ends of the bars are further guided and restrained by L-shaped guide members 43, only one of which is shown at the right-hand of FIG. 4. To the outer end of the bar 33 a piston cylinder assembly 45 is connected and in a similar manner a piston cylinder assembly 46 is connected to the bar 34 for the purpose of moving the inner ends of the filler bars into and out of an overlapping position with respect to the top of the tool 21.
In briefly describing now the method of employing the present invention, it will be appreciated that while a two-step nosing operation has been illustrated, the invention is not so limited and in a given pressing operation a single step may be sufficient.
A performed cold slab is brought to the press and arranged between the member 16 and 17, these elements, of course, being retracted from what is shown in FIG. 1. It will be appreciated that the workpiece is progressively compacted by it being sequentially fed to the press so that the punch 16 only compacts a small portion of the overall length of the slab at a time.
During the first pressing operation the cylinder 31 will have been operated to retract the tool behind the working surface of the punch 16. This, of course, will mean that the cylinders 45 and 46 have retracted the filler bars 33 and 34 to allow the tool 21 to be raised to its fullest extent. Once the slab has been compacted by operation of the press it will be indexed to bring its leading end under the surface 22 of the tool 21. At this point the cylinder 31 will be operated to allow the tool to lower itself towards the slab. After this occurs, the cylinders 45 and 46 will be operated to bring the filler bars 33 and 34 into a position illustrated in FIG. 1. The press then will be operated to cause the platen 45 to lower, bringing the working surface 22 of the tool 21 into engagement with the workpiece to deform the workpiece 20, as illustrated in FIG. 1.
In order to perform the second step of the nosing operation, the platen 15 is raised to its upper position and the cylinder 46 is operated to remove the filler bar 34 from above the tool 21. In the meanwhile the slab 20 will have been indented an amount to bring the next adjacent portion of the slab underneath the surface 22 of the tool 21. This leaves only the filler bar 33 above the tool. The press again is operated to cause the platen 15 to lower itself, again bringing the surface 22 of the tool 21 into engagement with the inner portion of overhung portion of the slab 20 to complete the nosing and to accomplish a condition illustrated, in phantom, in FIG. 2 relative to the slab.
It will be appreciated that instead of accomplishing a nosing operation, as explained, above the tool 21 could be employed to perform other indentations of the slab at periodic points along its length.
FIG. 5 illustrates an enlarged portion of the working surface 22 of the tool 21 in which to reduce the eccentric loading condition, it is formed in a number of equal steps 48.
In accordance with the provisions of the patent statutes, I have explained the principle and operation of my invention and have illustrated and described what I consider to represent the best embodiment thereof.