Method for manufacturing metal parts with split ends joined

Abstract

A method for manufacturing metal parts with split ends joined. An end of a metal plate or solid metal rod is split. The length of the incision is adjusted and a smooth split face is formed. A metal plate is secured by pinching both sides with a clamping device, or a solid metal rod is pinched on opposite portions on the periphery with a clamping device. The plate/rod is split longitudinally by slitting or cleaving the plate/rod by pressing a slitting or cleaving punch against the face of one end of the plate/rod. The splitting is advanced by repeating the operation of pressing the punch against the cleft of the splitting. In each splitting operation, the position of the clamping device is moved in advance of the next pressing by a stroke corresponding to the distance from one end of the plate/rod, to the distal end of a split-desired portion.

What is claimed is: 
     
         1 . A method for manufacturing metal parts with split ends joined, the method comprising:
 securing a metal plate having any of a rectangular, polygonal, or elliptical shape by pinching both sides thereof with a clamping device, or securing a solid metal rod having a cross-section of any of a circular, elliptical, rectangular, or polygonal shape by pinching at least two opposite-facing portions on the periphery thereof with a clamping device;   advancing splitting by pressing a slitting punch or a cleaving punch against a cleft of a split for repeatedly two or more times until a split length reaches a specified extent;
 inserting another metal plate between the split ends of the metal plate or the metal rod split; and 
 joining both the metals mutually and permanently by a method including any of pressing perpendicular to a splitting direction of the metal plate or the solid metal rod, welding, fusing, bolting, riveting, or gluing, 
   wherein, in advance of each time of each subsequent splitting operation of the two or more times,   a position of at least one side of the clamping device that pinches both sides of the metal plate in a prior operation of securing or that pinches at least two opposite-facing portions on a periphery of the solid metal rod in the prior operation of securing, is moved along the metal plate or the solid metal rod in advance by a stroke corresponding to a distance from a position of the cleft of the split toward a distal end of a split desired position, followed by securing of the metal plate by pinching both sides thereof with the clamping device, or by securing of the solid metal rod by pinching at least two opposite-facing portions on the periphery thereof with the clamping device,   wherein, in each interval between splitting operations of the two or more times, pressing of the splitting punch or the cleaving punch is suspended, and   wherein, on both sides in the case of the splitting punch or on one side in the case of the cleaving punch, a cutting edge is given a tapering shape having at least two taper portions of different angles or curvatures so that the taper portion of the side closer to a tip end of the cutting edge has a smaller inclination angle when measured counterclockwise from a horizontal axis extending perpendicular relative to a longitudinal axis passing through the cutting edge of the splitting punch or the cleaving punch, or a smaller curvature than that of the taper on the side apart from the tip end of the cutting edge.   
     
     
         2 . A method for manufacturing metal parts with split ends joined, the method comprising:
 determining a desired length of cutting plane in the thickness direction of a metal plate having any of a rectangular, polygonal, or elliptical shape, or in the diameter direction of a solid metal rod having a cross-section of any of a circular, elliptical, rectangular, or polygonal shape;   applying a slitting punch or a cleaving punch on the cross-section of the split-desired end of the metal plate, or the metal rod, on a boundary created by the cutting plane;   securing the metal plate by pinching both sides of a split-desired portion thereof with a clamping device, or securing the metal rod by pinching at least two opposite-facing portions on the periphery of a split-desired portion thereof with a clamping device;   advancing splitting by pressing a slitting punch or a cleaving punch against a cleft of a split for repeatedly two or more times until a split length reaches a specified extent;
 inserting another metal plate between the split ends of the metal plate or the metal rod split; and 
 joining both the metals mutually and permanently by a method including any of pressing perpendicular to a splitting direction of the metal plate or the solid metal rod, welding, fusing, bolting, riveting, or gluing, 
   wherein, in advance of each time of each subsequent splitting operation of the two or more times,   a position of at least one side of the clamping device that pinches both sides of the metal plate in a prior operation of securing or that pinches at least two opposite-facing portions on a periphery of the solid metal rod in the prior operation of securing, is moved along the metal plate or the solid metal rod in advance by a stroke corresponding to a distance from a position of the cleft of the split toward a distal end of a split desired position, followed by securing of the metal plate by pinching both sides thereof with the clamping device, or by securing of the solid metal rod by pinching at least two opposite-facing portions on the periphery thereof with the clamping device; and
 thereby the metal plate, or the metal rod, is partially split in a longitudinal direction along the cutting plane, 
   wherein, in each interval between splitting operations of the two or more times, pressing of the splitting punch or the cleaving punch is suspended,
 wherein, on both sides in the case of the splitting punch or on one side in the case of the cleaving punch, a cutting edge is given a tapering shape having at least two taper portions of different angles or curvatures so that the taper portion of the side closer to a tip end of the cutting edge has a smaller inclination angle when measured counterclockwise from a horizontal axis extending perpendicular relative to a longitudinal axis passing through the cutting edge of the splitting punch or the cleaving punch, or a smaller curvature than that of the taper on the side apart from the tip end of the cutting edge. 
   
     
     
         3 . The method for manufacturing metal parts with split ends joined according to  claim 1 , wherein the press-splitting is performed by pressing the slitting punch or the cleaving punch against the face of one end of the metal plate, or the solid metal rod, and against the cleft of the split repeating operations of securing the metal plate, or the solid metal rod, using the clamping device after moving either the clamping device on at least one side of the clamping devices or the metal plate, or the metal rod, by a specified stroke in one direction. 
     
     
         4 . The method for manufacturing metal parts with split ends joined according to  claim 1 , wherein, in the process of splitting the metal plate, or the solid metal rod, longitudinally with respect to the metal plate, or the solid metal rod, by slitting or cleaving and in the process of advancing the splitting by the slitting or cleaving further, the press-splitting by the slitting punch or the cleaving punch is performed with a progressive transfer method comprised of separate processing stages, and
 wherein, in each time of the press-splitting operation, the position of at least one side of the clamping device that pinches both sides of the metal plate or that pinches at least two opposite-facing portions on the periphery of the solid metal rod is moved in advance by a stroke corresponding to the distance from one end of the metal plate, or the solid metal rod, to the distal end of a split-desired portion.   
     
     
         5 . The method for manufacturing metal parts with split ends joined according to  claim 1 , wherein a groove cut or a nick line is made in advance on at least one of places in the peripheral portion of the end part of the metal plate, or the solid metal rod, and
 wherein the places are a place where the slitting punch or the cleaving punch is applied to and a place periphery of the metal plate that corresponds to the split-desired portion of the metal plate, or the solid metal rod.   
     
     
         6 . The method for manufacturing metal parts with split ends joined according to  claim 1 , wherein the joining of the split ends of the metal plate, or the split ends of the metal rod, and another metal plate is a joining between dissimilar metals. 
     
     
         7 . The method for manufacturing metal parts with split ends joined according to  claim 2 , wherein the press-splitting is performed by pressing the slitting punch or the cleaving punch against the face of one end of the metal plate, or the solid metal rod, and against the cleft of the split repeating operations of securing the metal plate, or the solid metal rod, using the clamping device after moving either the clamping device on at least one side of the clamping devices or the metal plate, or the solid metal rod, by a specified stroke in one direction. 
     
     
         8 . The method for manufacturing metal parts with split ends joined according to  claim 2 , wherein, in the process of splitting the metal plate, or the solid metal rod, longitudinally with respect to the metal plate, or the solid metal rod, by slitting or cleaving and in the process of advancing the splitting by the slitting or cleaving further, the press-splitting by the slitting punch or the cleaving punch is performed with a progressive transfer method comprised of separate processing stages, and
 wherein, in each time of the press-splitting operation, the position of at least one side of the clamping device that pinches both sides of the metal plate or that pinches at least two opposite-facing portions on the periphery of the solid metal rod is moved in advance by a stroke corresponding to the distance from one end of the metal plate, or the solid metal rod, to the distal end of a split-desired portion.   
     
     
         9 . The method for manufacturing metal parts with split ends joined according to  claim 2 , wherein a groove cut or a nick line is made in advance on at least one of places in the peripheral portion of the end part of the metal plate, or the solid metal rod, and
 wherein the places are a place where the slitting punch or the cleaving punch is applied to and a place periphery of the metal plate that corresponds to the split-desired portion of the metal plate, or the solid metal rod.   
     
     
         10 . The method for manufacturing metal parts with split ends joined according to  claim 2 , wherein the joining of the split ends of the metal plate, or the split ends of the metal rod, and another metal plate is a joining between dissimilar metals.