Forged roller
A machine, method and tooling to precision cold-form roller blanks for anti-friction bearings. The machine is a multistage progressive former using floating die cavities to enable simultaneous shaping of the ends of the roller with high accuracy and without flash. The tools and staged forming create an improved roller with an advantageous grain pattern and devoid of structural defects previously attributable to the presence of sheared end face material in the radiused corners of the blank and flash at its mid-section.
1. A set of tooling for a cold-forming machine comprising a die case arranged to be fixed on a die breast of the machine, the case being arranged to present a die cavity on a working axis in opposed relation to a tool on a slide reciprocal towards and away from the die breast, and a floating die ring arranged to be supported on the case for limited movement relative to the die case and die cavity along the direction of slide movement independent of direct correspondence with movement of the tool while radially confining a mid-section of a blank such that friction between the mid-section of the blank is eliminated as a retarding force.
2. A set of tooling according to claim 1 , wherein the case has a cylindrical portion with an axis aligned with the direction of slide movement when it is mounted in the cold-forming machine, said floating die ring having a part telescoped on said cylindrical portion to support said ring for movement in the direction of slide movement.
3. A set of tooling according to claim 1 , including a second die case for mounting on the die breast, and a second floating die ring arranged to be supported on the second die case for limited movement relative to the second die case along the direction of slide movement, the second floating die ring being arranged to receive a blank formed at the first die case and first floating die ring.
4. A set of tooling according to claim 1 , for forming roller blanks for use in an anti-friction bearings, comprising a pair of circular tool and die cavities each having a major diameter and designed to simultaneously cold-form the ends of a blank of circular cross-section, the die ring having a circular through bore, the circular tool and die cavities having respective configurations to form the ends of a sheared blank with radiused corners that have radii that are small in comparison to the diameter of the blank, the through bore being at least as large as a major diameter of the tool and die cavities.
5. A set of tools for forming roller blanks for use in an anti-friction bearings, comprising a pair of circular tool and die cavities each having a major diameter and designed to simultaneously cold-form the ends of a blank of circular cross-section, and a separate die ring having a circular through bore for constraining a mid-section of the blank, the die ring being arranged to move towards the die cavity independently of direct correspondence with movement of the tool cavity such that friction between the mid-section is effectively eliminated as a retarding force, the tool and die cavities having respective configurations to form the ends of a sheared blank with radiused corners that have radii that are small in comparison to the diameter of the blank, the through bore being at least as large as a major diameter of the tool and die cavities.
6. A set of tooling for a cold-forming machine comprising a die case arranged to be fixed on a die breast of the machine, the case being arranged to present a die cavity on a working axis in opposed relation to a tool on a slide reciprocal towards and away from the die breast, and a floating die ring arranged to be supported on the case for limited movement relative to the die case and die cavity along the direction of slide movement while radially confining a mid-section of a blank, the die cavity being paired with a tool cavity for simultaneously forming the ends of a blank with radiused corners, the floating die ring being arranged for shaping the blank by circumferentially constraining its mid-section while being driven towards the die cavity by friction between the floating die ring and the blank independently of direct correspondence with movement of the tool cavity such that friction between the mid-section of the blank is effectively eliminated as a retarding force which would otherwise operate to diminish the filling of the radiused corners of the die cavity with the blank material.
7. A set of tooling for cold-forming metal roller blanks comprising a pair of tool and die cavities for simultaneously forming the ends of a blank with radiused corners and a floating die ring for shaping the blank by circumferentially constraining its mid-section while being driven towards the die cavity by friction between the floating die ring and the blank independently of direct correspondence with movement of the tool cavity such that friction between the mid-section of the blank is effectively eliminated as a retarding force which would otherwise operate to diminish the filling of the radiused corners of the die cavity with the blank material.
8. A set of tooling as set forth in claim 7 , wherein the die cavity is in a case and said floating die ring is arranged to be supported by said case for movement towards said die cavity.
9. A set of tooling as set forth in claim 8 , wherein said case has a cylindrical portion with its axis aligned with the direction of slide movement and said floating die ring has a skirt telescoped over the cylindrical portion of said case.
10. A set of tooling as set forth in claim 9 , wherein said die cavity is an insert carried in said case.
11. A set of tooling as set forth in claim 7 , including a second pair of tool and die cavities and a floating die ring for said second die cavity, said second pair of tool and die cavities being arranged to shape the ends of a blank received from said first tool and die cavities and the first floating die ring.
12. A set of tooling as set forth in claim 11 , wherein said first floating die ring is sized to form the mid-section of the blank to produce a slip fit in the second floating die ring.
13. A set of tooling as set forth in claim 11 , including a third pair of tool and die cavities configured to finish shape a blank received from the second pair of tool and die cavities.
14. A set of tooling as set forth in claim 13 , including a guide, separate from said slide, to closely align said third pair of cavities.
15. A set of tooling as set forth in claim 13 , wherein said pairs of tool and die cavities have associated passages for circulating coolant to maintain said tool cavities at a predetermined temperature range.