Method and apparatus using a split case die to press a part and the part produced therefrom

Abstract

A split case die is used to press powder, wherein the die parts are moveable in a direction non-parallel to the direction of the pressing axis. The part produced by such a split case die has an external surface with parting line marks oriented in a direction non-perpendicular to the pressing axis.

1 . A cutting insert comprised of a sintered green part having a top surface and a bottom surface with side walls therebetween and, wherein at least two opposing side walls are symmetric about a longitudinal axis and, wherein the at least two opposing side walls each have restrictions extending therein, wherein the part further includes parting line marks extending from the top surface to the bottom surface, wherein the parting line marks are from die segments during a powder pressing operation used to fabricate the insert. 
     
     
         2 . The cutting insert according to  claim 1 , wherein the restrictions formed in the at least two opposing side walls are comprised of segments with two angled portions, wherein a first angled portion forms a positive angle Y with the longitudinal axis and a second angled portion forms a negative angle Z, which together define a restriction within each of the at least two side walls. 
     
     
         3 . The cutting insert according to  claim 2 , wherein a spacer portion exists between the two angled portions. 
     
     
         4 . The cutting insert according to  claim 3 , wherein the spacer portion is straight. 
     
     
         5 . The cutting insert according to  claim 4 , wherein the spacer portion is parallel to the longitudinal axis. 
     
     
         6 . The cutting insert according to  claim 1 , wherein restrictions formed in the at least two opposing side walls have a concave surface. 
     
     
         7 . The cutting insert according to  claim 6 , wherein the concave surfaces are curved. 
     
     
         8 . The cutting insert according to  claim 7 , wherein the concave surfaces have at least one point between the ends of each concave surface that is tangent to the longitudinal axis. 
     
     
         9 . The cutting insert according to  claim 1 , wherein the restrictions formed in the at least two opposing side walls make up part of a bellows shape, wherein the restriction is located at an inner section along the bellows. 
     
     
         10 . The cutting insert according to  claim 9 , wherein the bellows is comprised of adjacent convex and concave sections. 
     
     
         11 . The cutting insert according to  claim 1 , wherein the restrictions formed in the at least two opposing side walls are comprised of threads on the walls extending around the perimeter of the insert exterior in the form of a spiral flute. 
     
     
         12 . A method for making a part from powder using a uni-axial press, wherein the method comprises the steps of:
 a) with a die having at least two separable die parts that, in the assembled state, define a die cavity with a die chamber therein and a pressing bore along a pressing axis extending from opposing sides of the chamber through the die outer surface, positioning the die parts together in the assembled state;   b) filling the die and the pressing bores with powder;   c) using at least one top ram and at least one bottom ram movable relative to one another along the pressing axis proximate to the chamber; compressing the powder to within the region of the chamber; and   d) with each separable die part having a chamber part which together defines the die chamber, spacing apart the top and bottom rams from each other and separating the die parts in a direction non-parallel to the pressing axis to release the part.   
     
     
         13 . The method of making a part according to  claim 12 , wherein after the powder is compressed and before the part is released, compression on the part is relieved to provide partial volume relief to the part. 
     
     
         14 . The method of making a part according to  claim 13 , wherein the partial volume relief to the part is provided by spacing apart by a small amount the top and bottom rams to decompress the part prior to release of the part. 
     
     
         15 . The method according to  claim 12 , wherein the die moves in a direction that is radial to the pressing axis. 
     
     
         16 . The method according to  claim 12 , wherein the die moves in a direction that is offset from the pressing axis. 
     
     
         17 . The method according to  claim 12 , wherein the die moves in a direction that is linear. 
     
     
         18 . The method according to  claim 11 , wherein the die moves in a direction that is non-linear. 
     
     
         19 . The method according to  claim 12 , wherein the assembled die captures the part so that it is immovable within the die cavity. 
     
     
         20 . The method according to  claim 19 , further including the step of urging the die parts apart after the part has been formed to release the part. 
     
     
         21 . The method according to  claim 12 , further comprising the step, prior to the step of filling the die chamber, of placing within the uni-axial press any particular base plate with a particular die set to permit the fabrication of different parts using the same uni-axial press. 
     
     
         22 . The method according to  claim 12 , further comprising the step of inserting a removable core rod within the chamber to define a core bore through the chamber in a direction non-parallel to the pressing axis. 
     
     
         23 . An article formed using a uni-axial press motion having a die with a cavity extending therethrough along a pressing axis, wherein the cavity is made up of a chamber and a pressing bore on each side of the chamber with a top ram and a bottom ram independently movable along the pressing axis within the cavity, wherein the article is formed by the steps of:
 a) with a die having at least two separable die parts that, in the assembled state, define a die chamber therein and a pressing bore along a pressing axis extending from opposing sides of the chamber through the die outer surface, positioning the die parts together in the assembled state;   b) filling the die and the pressing bores with powder;   c) using at least one top ram and at least one bottom ram movable relative to one another along the pressing axis proximate to the chamber; compressing the powder to within the region of the chamber; and   d) with each separable die part having a chamber part which together defines the die chamber, spacing apart the top and bottom rams from each other and separating the die parts in a direction non-parallel to the pressing axis to release the part.   
     
     
         24 . The article according to  claim 23 , wherein after the powder is compressed and before the part is released, compression on the part is relieved to provide partial volume relief to the part. 
     
     
         25 . The article according to  claim 23 , wherein the assembled die captures the part so that it is immovable within the die. 
     
     
         26 . The method according to  claim 23 , further comprising the step of inserting a removable core rod within the chamber to define a core bore through the chamber at the compression region in a direction perpendicular to the pressing axis. 
     
     
         27 . An article comprised of compacted powder, wherein the article has a body with a primary axis extending therethrough, wherein the body is formed through a pressing operation and, wherein the external surface of the body has parting line marks representing mating lines of split case die parts assembled to form a die chamber for forming the part in a direction non-perpendicular to the pressing axis. 
     
     
         28 . The article according to  claim 27 , wherein the article is a cutting insert that has been sintered from the part.