Cold forming tool, machine and method

A cold forming tool having a substantially planar part engaging surface and a plurality of regularly-spaced teeth with tips wherein the plurality of regularly-spaced teeth project away from an outer surface, the cold forming tool comprising:

• at least one penetration zone comprising some of the plurality of regularly-spaced teeth;
• a calibration zone arranged adjacent the at least one penetration zone;
• the calibration zone comprising some of the plurality of regularly-spaced teeth;
• the plurality of regularly-spaced teeth having a tooth height that increases substantially from the at least one penetration zone to the calibration zone;
• a distance between the outer surface and a reference plane decreasing from the at least one penetration zone to the calibration zone;
• and
• a rate of increase in the tooth height between the at least one penetration zone and the calibration zone being greater than a rate of decrease in the distance between the outer surface and the reference plane between the at least one penetration zone and the calibration zone, whereby a distance between the tips and the reference plane increases substantially from a beginning of the at least one penetration zone to a beginning of the calibration zone,
• wherein the cold forming tool is adapted to form a part by rotating the part and ensuring that the part has substantially no axial displacement.

A cold forming machine comprising:

• a first cold forming tool comprising a first part engaging surface and a plurality of regularly-spaced teeth with tips wherein the plurality of regularly-spaced teeth project away from a first surface;
• the first cold forming tool comprising at least one penetration zone comprising some of the plurality of regularly-spaced teeth, a calibration zone arranged adjacent the at least one penetration zone, the calibration zone comprising some of the plurality of regularly-spaced teeth, the plurality of regularly-spaced teeth having a tooth height that increases substantially from the at least one penetration zone to the calibration zone, a distance between the first surface and a first reference location decreasing from the at least one penetration zone to the calibration zone, and a rate of increase in the tooth height between the at least one penetration zone and the calibration zone being greater than a rate of decrease in the distance between the first surface and the first reference location between the at least one penetration zone and the calibration zone, whereby a distance between the tips and the first reference location increases substantially from a beginning of the at least one penetration zone to a beginning of the calibration zone;
• a second cold forming tool having a second part engaging surface and a plurality of regularly-spaced teeth with tips wherein the plurality of regularly-spaced teeth project away from a second surface;
• the second cold forming tool comprising at least one penetration zone comprising some of the plurality of regularly-spaced teeth, a calibration zone arranged adjacent the at least one penetration zone, the calibration zone comprising some of the plurality of regularly-spaced teeth, the plurality of regularly-spaced teeth having a tooth height that increases substantially from the at least one penetration zone to the calibration zone, a distance between the second surface and a second reference location decreasing from the at least one penetration zone to the calibration zone, and a rate of increase in the tooth height between the at least one penetration zone and the calibration zone being greater than a rate of decrease in the distance between the second surface and the second reference location between the at least one penetration zone and the calibration zone, whereby a distance between the tips and the second reference location increases substantially from a beginning of the at least one penetration zone to a beginning of the calibration zone;
• and
• an arrangement for moving the first and second cold forming tools,
• wherein the cold forming machine is adapted to form a part by rotating the part and ensuring that the part has substantially no axial displacement.

A cold forming tool having a plurality of teeth with tips wherein the plurality of teeth project away from an outer surface, the cold forming tool comprising:

• a penetration zone comprising some of the plurality of teeth;
• a calibration zone arranged adjacent the penetration zone and comprising some of the plurality of teeth;
• each adjacent tooth of the penetrating zone increasing in height from a beginning of the penetration zone to a beginning of the calibration zone;
• a distance between the outer surface and a reference point decreasing from a beginning of the penetration zone to at least a beginning of the calibration zone;
• and
• a rate of increase in the tooth height between the penetration zone and the calibration zone being greater than a rate of decrease in the distance between the outer surface and the reference point between the penetration zone and the calibration zone, whereby a distance between the tips and the reference point substantially increases from a beginning of the at least one penetration zone to a beginning of the calibration zone,
• wherein the cold forming tool is adapted to form a part by rotating the part and ensuring that the part has substantially no axial displacement.