US3187549A

US3187549A - Segmented die assembly

Info

Publication number: US3187549A
Application number: US142579A
Authority: US
Inventors: Charles W Guy
Original assignee: North American Aviation Corp
Current assignee: North American Aviation Corp
Priority date: 1961-10-03
Filing date: 1961-10-03
Publication date: 1965-06-08
Anticipated expiration: 1982-06-08
Also published as: GB941230A

Description

June 8, 1965 c. w. GUY 3,187,549

SEGMENTED DIE ASSEMBLY Filed Oct. 3. 1961 INVENTOR. CHARLES W. GUY

"Hi-lr ri QQQMQ ATTORNEY United States Patent 3,187,549 SEGMENTED DIE ASSEMBLY Charles W. Guy, Northridge, Calila, assignor to North American Aviation, Inc. Filed Oct. 3, 1961, Ser. No. 142,579 4 Claims. (Cl. 72-478) This invention relates to a segmented die assembly and more particularly relates to a forming die which may be selectively constructed and arranged to comprise various die cavity configurations by utilizing a plurality of integrated die segments. 7

Present-day forming dies generally constitute unitary structures which only afford one or a very limited number of forming operations. Such prior art die structures generally involve relatively high production, maintenance and replacement costs. Furthermore, such die structures are particularly inadequate when used in conjunction with explosive forming methods. Such an undesirable condition primarily exists due to the fact that the die edges thereof provide a relatively short life expectancy due to the extremely high damaging explosive forces which are inherently imparted thereon during such an operation.

The present invention has overcome many of the above described prior art inadequacies by providing a segmented die assembly which may be expeditiously assembled to provide a die cavity of predetermined configuration. The die assembly of this invention essentially comprises a first layer of first die segments which are arranged to have their respective adjacent edges in substantial abutting relation to each other and a second layer of second die segments arranged on said first layer with said second segments overlying the adjacent abutting edges formed by said first segments. Said die segments are so constructed and arranged to provide an internal die cavity of predetermined configuration. Means are provided to removably secure the first and second layers in relatively fixed rela tion to each other. Therefore, it can be readily seen that the configuration of the internal die cavity of the single die assembly may be selectively and expeditiously changed to meet a wide range of specific design requirements.

An object of this invention is to provide a segmented die assembly which is low in cost and durable in'construction.

A further object of this invention is to provide a segmented die assembly which may be expeditiously assembled and disassembled to provide internal die cavities comprising a Wide range of desired configurations.

A still further object of this invention is to provide a segmented die assembly whereby manufacture, maintenance and replacement costs are substantially reduced.

These and other objects of this invention will become apparent from the following description taken in connection with the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of a segmented die assembly, illustrating the novel concepts of this invention;

FIG. 2 is a plan view taken in the direction of lines 2-2 in FIG. 1;

FIG. 3 discloses a preferred die segment configuration;

FIG. 4 is a partial sectional view more particularly disclosing the novel die segment interlocking features of this invention; and

FIG. 5 is a partial cross-sectional view disclosing an alternative internal die cavity construction and arrangement.

FIG. 1 is a cross-sectional view of a segmented die assembly illustrating the novel concepts of this invention. A base or foundation 19 comprising a cement constituent or the like is adapted to support the segmented die assembly 11 which is arranged on longitudinal axis The die assembly 11 comprises a plurality of die segments 12 which are arrangedwith their respective juxtaposed edges 3,187,549 Patented June 8, 1965 ice.

in substantial abutting relationship (FIG. 2), to thus form one or more layers. It should be understood that although FIG. 1 discloses seven such layers, that any desired number thereof may be utilized depending on the particular design requirements. The die segments may comprise, for example, a high strength steel constituent which is capable of withstanding the extreme explosive forming forces which may be subsequently imparted thereon.

FIG. 3 discloses a preferred die segment 12 configuration. As shown, the segment 12 comprises a substantial truncated cone configuration having curved base and apex portions and side portions defined by the included angle a. As illustrated, the angle or constitutes 45. However, it should be understood that such an angle may be more or less than said '45 depending on the particular number of segments it is desired to employ for each layer. It should be also understood that other die segment designs may be employed, as will be hereinafter more 'fully discussed.

As shown in FIG. 1, a plurality of holes 13 are preferably formed through the die segments 12 to facilitate the reception and retention of fastening means preferably in the form of bolts 14 therein. Such fastening means function to maintain the respective overlying die segment layers in fixed relationship relative to each other.

It should be further noted, with respect to the illustrated die segment of FIG. 3, that a curved surface 15 may be constructed and arranged to face the longitudinal axis X--X (FIG. 1) to thus comprise any desired internal die cavity configuration when assembled together with the other die segments of the die assembly. For example, as shown in FIG. 2, the internally arranged curved surfaces 15 forming the die cavity and the externally arranged curved surfaces 16 are constructed and arranged to form radii R and R respectively. However, it should be understood that the particular shape of the internal die cavity formed by means of surfaces 15 may com-prise any desired configuration depending on the particular formed workpiece design desired. For example, elliptical, rectangular, spherical, etc. shapes may be readily obtained pursuant to the novel segmented die concepts of this invention.

FIG. 4 more particularly discloses the novel die segment interlocking features'of this invention. As shown, the juxtaposed edges 17 of the individual die segments in any one layer are covered by the die segments comprising the adjacent layers. Thus, when the securing bolts 14 are secured to the stacked die segment layers, an extremely sturdy and integrated die assembly is afforded primarily due to the above described interlocking features of this invention. It is further obvious from the above description that by utilizing die segments having a predetermined thickness and surface 15 configuration, the desired total height and internal die configuration of the material 22 such as a metallic weldment or standard plaster in order to provide the desired internal die surface configuration 23.

Referring once again to FIG. 1, the die assembly 11 of this invention may be utilized in a conventional manner by initially placing a workpiece, shown by phantom lines 7 W, in proper position onto the top surface portions of the die assembly 11.; A standard explosive charge 18 of ap propriate size is then constructed and arranged thereabove as shown. The internal die cavity formed by the internal a surface portions 15 of the individual die segments 2 is shown in 1 as comprising a cylindrical shape. Thus, when the explosive charge 18 is subsequently ignited, the workpiece W will be forced and formed against said forming diecavity. v

From the above description it can be seen that mainte nance procedures are materially enhanced and-the costs thereof substantially reduced. For example, it can be readily seen that damage might occur to the edge portions 19 of the uppermost die segments 12- pursuant to repeated use of the die assembly. Such damage oft-times functions tov destroy the close workpiece tolerance desired. However, the novel aspects of this invention provide that the die segments comprising the top layer may be either turned over, replaced with new die segments or substituted for other die segments of the assembly. It should be further noted that such damaged segments may be readily dis- --assembled and machined 'to, comprise a larger radii at the internal surface portions 15. thereof.

Although this. invention has been described and illustrated in detail, it isto be understood that the same is by way of illustration and example only and is not to be,

, :3. tudinal axis and comprising at least two layers of die segments, said assembly comprising a first layer of first die segments arranged to have their respective adjacent I edges insubstantial abutting relation to each other, a

taken byway of limitation, the spirit and scope of this 7 25. A sebrnentcd, female die assembly formed on a longi-v second layer of second die segments arranged on said first layer with said second segments overlapping the adjacent abutting edges formed by said first segments, said first and second segments having die cavity forming surfaces arrange-d to'fiace said axis to form a die cavity of predetermined configuration, and means securing said first and second layers in relatively fixed relation to each other. 3. The invention or" claim 2 wherein said die cavity forming surfaces of said first and second layers are substantially flush relative to each other.

4. The invention of claim 2' wherein said die cavity forming surfaces of said first segments are offset from said second segments, relative to said axis, and a filling selectively formed thereon to provide a desired-die cavity a surface configuration.

References Cited bythe Examiner UNITED STATES PATENTS 658,187 9/00. Mehr 113-48 1,621,281 3/27 Sheffield M 76-107 2,679,172 5/42 Clevenger et al. 113-49 2,744,426 5/56 Lyon 76-107 7 FOREIGN PATENTS 559,142 2/44 Great Britain.

893,880 7/49 Germany.

CHARLES w; LANHAM, Primary Examiner. WILLIAM J. STEPHENSON, NEDWIN BERGER,

V Examiners.

Claims

1. A SEGMENTED FEMALE DIE ASSEMBLY COMPRISING A FIRST LAYER OF FIRST DIE SEGMENTS ARRANGED TO HAVE THEIR RESPECTIVE ADJACENT EDGES IN SUBSTANTIAL ABUTTING REALTION TO EACH OTHER, A SECOND LAYER OF SECOND DIE SEGMENTS ARRANGED ON SAID FIRST LAYER WITH SAID SECOND SEGMENT OVERLAPPING THE ADJACENT ABUTTING EDGES FORMED BY SAID FIRST SEGMENTS AND MEANS SECURING SAID FIRST AND SECOND LAYERS IN RELATIVELY FIXED RELATION TO EACH OTHER.