Tools and methods for finishing a previously created thread without cutting

A method of creating a screw thread in a work piece, in particular an internal thread comprising the steps of:

• a) creating an initial thread by one of cutting means or non-cutting means, wherein the non-cutting means include any one or more of tapping, milling, turning, grinding, winding, or rolling;
• and
• b) finishing the initial thread without cutting by using a tool that has a plurality of forming wedges that, in cross-section, exhibit two flanks, such that at least one of the forming wedges is centered in the previously created initial thread by at least one of the exhibited two flanks, the at least one of the exhibited two flanks including an expansion for positioning the at least one forming wedge in the previously created thread;
• c) wherein the plurality of forming wedges exhibits substantially the same expansion with substantially the same cross-sectional shape in a forming region that extends from the forming wedge tip of each forming wedge to the expansion, such that the cross-sectional shape is convexly curved in a first section, concavely curved in a second section, and convexly curved again in a third section.

A tool for finishing a previously created thread, such as an internal thread, without cutting, comprising:

• a) at least one thread-forming portion that rotates about a tool axis, the thread-forming portion having multiple forming wedges;
• b) wherein the forming wedges in cross-section comprise two flanks that diverge from one another beginning at a forming wedge tip, the forming wedge tip being shaped as any of an acute angle, a rounded region, or a flattened region;
• c) wherein at least one of the two flanks include at least one expansion for positioning the forming wedge in the previously created thread;
• d) wherein the plurality of forming wedges exhibits substantially the same cross-sectional shape in a forming region that extends from the forming-wedge tip of each forming wedge to the expansion, such that the forming region has an at least approximately polygonal shape in cross-section, including any of a triangle, quadrangle, or trapezoid shape, the corners of the polygonal shape being any one or more of pointed or rounded.

A tool for finishing a previously created thread, such as an internal thread, without cutting, comprising:

• a) at least one thread-forming portion that rotates about a tool axis, the thread-forming portion having multiple forming wedges;
• b) wherein the forming wedges in cross-section comprise two flanks that diverge from one another beginning at a forming wedge tip, the forming wedge tip being shaped as any of an acute angle, a rounded region, or a flattened region;
• c) wherein at least one of the two flanks include at least one expansion for positioning the forming wedge in the previously created thread;
• d) wherein the plurality of forming wedges exhibits substantially the same cross-sectional shape in a forming region that extends from the forming-wedge tip of each forming wedge to the expansion, such that the cross-sectional shape of the forming region is one of an isosceles triangle, a triangle with a 60° internal angle, or an equilateral triangle, the triangle having a rounded or flattened tip.

A method of creating a screw thread in a work piece, in particular an internal thread comprising the steps of:

• a) creating an initial thread by one of cutting means or non-cutting means, wherein the non-cutting means include any one or more of tapping, milling, turning, grinding, winding, or rolling;
• and
• b) finishing the initial thread without cutting by using a tool that has a plurality of forming wedges that, in cross-section, exhibit two flanks, such that at least one of the forming wedges is centered in the previously created initial thread by at least one of the exhibited two flanks, the at least one of the exhibited two flanks including an expansion for positioning the at least one forming wedge in the previously created thread;
• c) wherein the plurality of forming wedges exhibit substantially the same expansion with substantially the same cross-sectional shape in a forming region that extends from the forming wedge tip of each forming wedge to the expansion, such that the forming region has an at least approximately polygonal shape in cross-section, including any of a triangle, quadrangle, or trapezoid shape, the corners of the polygonal shape being any one or more of pointed or rounded.

A method of creating a screw thread in a work piece, in particular an internal thread comprising the steps of:

• a) creating an initial thread by one of cutting means or non-cutting means, wherein the non-cutting means include any one or more of tapping, milling, turning, grinding, winding, or rolling;
• and
• b) finishing the initial thread without cutting by using a tool that has a plurality of forming wedges that, in cross-section, exhibit two flanks, such that at least one of the forming wedges is centered in the previously created initial thread by at least one of the exhibited two flanks, the at least one of the exhibited two flanks including an expansion for positioning the at least one forming wedge in the previously created thread;
• c) wherein the plurality of forming wedges exhibits substantially the same expansion with substantially the same cross-sectional shape in a forming region that extends from the forming wedge tip of each forming wedge to the expansion, such that the cross-sectional shape of the forming region is one of an isosceles triangle, a triangle with a 60° internal angle, or an equilateral triangle, the triangle having a rounded or flattened tip.