US 4,590,780 AGranted

Process and apparatus for producing at least two forgings on a hot-forming press

AssigneeHatebur Umformmaschinen AG

InventorErnst Bachmann

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Abstract

Starting from a pre-heated bar, there is sheared-off first a portion (41) which, in a first forming stage of the machine, is formed into a tier shaped pressed article. In the second forming stage, the pressed article is further formed so that it has an inner ring (J), an outer ring (A) arranged co-axially to this and a radial annular web (S) connecting the two rings (J,A). The sheared-off outer ring (44) is therefore ejected in the next to last stage, while in the last working stage the inner ring (45) separated from the outer ring is subjected to further working. This last working stage involves stamping out a waste piece (35) and shearing-off an annular web (38). It is also possible to carry out a forming operation in this last working stage to upset the remaining inner ring (22a). By means of this process which provides for the elimination of the finished outer ring (44) in the last working stage, the radial annular web (38) can be supported over its full cross-sectional surface during the shearing-off operation.

Claims2

Dependent claims

A process for producing at least two forgings in a multistage work cycle on a hot-forming press by means of cooperating punch and die members including the steps of producing a pressed article which has at least two coaxial parts connected to one another by a radially extending annular web, said parts being an inner part and an outer part, of which at least the outer part, having the greater outside diameter, is annular, and the inner part is cup-shaped with a closed end, severing the parts from one another in the region of the annular web by shearing, whereby said severing comprises

serving first the outer part in a first severing-processing state at a predetermined first annular separating interface which cuts through the radial annular web and leaves a remaining radially extending annular web connected to the inner part and then ejecting the outer part as a finished part;
whereafter
transporting the inner part having a closed end, including said remaining radial annular web section still attached to it into a second severing-processing stage, in which at said second severing-processing stages comprises:
punching out the centrally located closed end of the inner part to form a hollow annular inner part and ejecting the closed end as a waste piece, severing the remaining radial annular web section from the inner part at a predetermined second annular separating interface which cuts through the web section, by contacting the entire face which defines the remaining radially extending annular web section with a corresponding annular supporting surface provided at the front of a die member as the remaining radial annular web is severed therefrom to form a cut-off web, and
moving said punch along a direction of travel to eject the cut-off web section separately from the hollow annular inner part and further eject the annular inner part along said direction of travel of the punch member.

2 more elements

In a hot forming press having cooperating punch and die members, and apparatus for producing at least two forgings in a multi-stage work cycle from a pressed article which has at least two co-axial parts connected to one another by a radially extending annular web (38), said parts being an inner part (22a) and an outer part (16), the apparatus comprising in each stage, a punch mounted for reciprocation with respect to a stationary die located co-axially opposite said punch, the punch having, in a first severing processing stage (15), an inner stamping punch (20) mounted coaxially and movably with respect to said punch, a stripper sleeve (24) mounted to slide on a peripheral surface of the stamping punch (20), and a spring biased inner retaining pin (17) mounted within the inner stamping punch (20) and movably mounted relative thereto, wherein motion of the retaining pin (17), the stamping punch (20) and the stripper sleeve (24) are coordinated with one another so that in the first severing processing stage only, the annular outer part (16) is severed and then ejected as a finished part, further comprising in a second severing processing stage (26) at the stationary die (32), an annular supporting surface (31) for supporting a section of said radially extending annular web (38) attached to the inner part (22a) and a movable bracing device (29), having a ring surface (28) corresponding to the outer diameter of said inner part (22a), said annular supporting surface (31) being located on said stationary die (32) and said movable bracing device (29) being positioned within said stationary die (32), the punch of said second severing processing stage (26) being provided within an inner punch stamper (33) and in its operating front face with a retaining spring biased pin (27) for pushing said inner part (22a) into said stationary die (32) and against said ring surface (28) as well as a waste piece (35) of the article into the die for ejection after it has been severed from said innner part (22a) by said inner punch stamper (33), said inner punch stamper (33) cooperating with said movable bracing device (29) to effect said severing, and being further provided with a stamping punch sleeve (37) mounted to slide on a peripheral surface of said punch stamper (33), having an outer diameter also corresponding to the outer diameter of said inner part (22a) and cooperable with said annular support surface (31), whereby the motions of said bracing device (29) and said punch sleeve (37) are coordinated with one another so that the section of said web (38) is severed by said punch sleeve (37) and said annular supporting surface (31) and the motions of said punch stamper (33) and said punch sleeve (37) are coordinated to one another so that said inner part (22a) is stripped off by said sleeve from said punch, and being finally provided with a stripper (39) for stripping off said web from said punch sleeve (37) and said first and second stages being located adjacent each other with means for moving said inner part (22a) and its web (38) from said first stage to said second stage.

Dependencies are inferred from the claim text.