Abstract: An extrusion assembly, which fits into a hydraulic press, includes an upper die plate and a lower die plate mounted to one another by die guide posts. A lead bar is coupled to the upper die plate at one end and to a mandrel at its other end and includes helical grooves on its surface that mate with helical protrusions on lead nuts. A die shell and insert are mounted concentrically with mandrel and receive a gear blank. As hydraulic press pushes lead bar axially toward gear blank, lead nuts impart a rotational motion to lead bar, which causes mandrel to move with a helical motion as it is pressed into and pulled out of gear blank.

Abstract: A gear rolling machine includes a pair of gear rolling dies for finish forming teeth on external gear blanks. A force sensor is mounted to the machine to monitor the amount of force applied to the gear blank by the rolling dies as one rolling die is infed toward the other during the rolling process. The sensor is electronically connected to a controller that stops the infeed when a predetermined force level is attained during the rolling process.

Abstract: An extrusion assembly, which fits into a hydraulic press, includes an upper die plate and a lower die plate mounted to one another by die guide posts. A lead bar is coupled to upper die plate at one end and a hydraulic chuck at its other end and includes helical grooves on its surface that mate with helical protrusions on lead nuts. Hydraulic chuck selectively retains a mandrel assembly. A die shell and insert are mounted concentrically with mandrel assembly and receive a gear blank. A bottom rest assembly is located below die shell and is positioned to receive mandrel assembly. An ejection assembly is positioned between bottom rest assembly and a hydraulic cylinder and includes ejector pins. As hydraulic press pushes lead bar axially through gear blank, lead nuts impart a rotational motion to lead bar, which causes mandrel to move with a helical motion as it is pressed into and through gear blank. Chuck then releases mandrel assembly onto bottom rest assembly and lead bar is retracted.

Abstract: A extrusion die assembly for cold extruding internally and/or externally toothed gears and the like, particularly internally toothed ring gears, with the mandrel for forming the internal teeth in the workpiece including axially successive sets of die teeth, with each set including a full complement of annularly arranged and equally spaced die teeth, and the die teeth from the leading set to the trailing set increasing progressively in diameter.In one embodiment, the die teeth from one set to the next on the mandrel extrude the gear teeth in equal radial depth, and in a second embodiment, the die teeth of each succeeding mandrel set extrude the gear teeth by displacing an equal volume of material from one set to the next.

Abstract: A forging die and a forging die manufacturing method for extruding helical gears wherein the lead end face of each die tooth is made up of harmonious S-shaped curves with each curve having maximized-radii contours. The shape of the S-shaped curves is formed by dividing the cylindrical surface at the lead end face and the full depth perimeter into an equal number of equally spaced points, connecting these points up into pairs so as to establish the shortest distance between the pairs of points and using these pairs as the end points for the S-shaped curves.