Method and apparatus for forming threads with variable pitch
OwnerWilliam P. Greeninventor
Life of this patent
Estimating the term…
Abstract
Apparatus and methods for forming a thread of varying pitch by utilizing a threading assembly which includes a plurality of threading elements having thread cutting or forming portions on the different elements for engaging the work piece at different locations, with the assembly and work piece being driven both rotatively and at the same time axially relative to one another to form the thread. The rate of axial advancement per revolution between the work piece and each of the threading elements is varied, and the elements of the assembly are also shifted axially relative to one another during the rotary and axial movement, to give the thread its varying pitch.
Claims61
Apparatus for forming a thread of varying pitch on a work piece, comprising:
- an assembly including a plurality of threading elements having thread forming portions on said elements for engaging the work piece at different locations;
- and
- means for moving said work piece and said assembly of threading elements relative to one another, both rotatively about an axis and at the same time axially, to form the thread;
- said means being constructed to vary the rate of relative axial advancement between said work piece and each of said elements per degree of relative rotary movement therebetween, and to shift said elements axially relative to one another, during the rotary and axial movement, to give the thread said varying pitch.
Apparatus for forming a thread of varying pitch on a work piece, comprising:
- an assembly including a plurality of threading elements having thread forming portions on said elements for engaging the work piece at different locations;
- and
- means for moving said work piece and said assembly of threading elements relative to one another, both rotatively about an axis and at the same time axially, to form the thread;
- said means being constructed to shift said elements axially relative to one another during said rotary and axial movement.
The method of forming a thread of varying pitch on a work piece, comprising:
- moving said work piece and an assembly of threading elements having thread forming portions relative to one another both rotatively about an axis and at the same time axially, to form the thread;
- and
- varying the rate of relative axial advancement between said work piece and each of said elements per degree of relative rotary movement therebetween, and shifting said elements axially relative to one another during the rotary and axial movement, to give the thread said varying pitch.
A threading tool for forming a thread of varying pitch on a work piece, comprising:
- an assembly including a plurality of threading elements having thread forming portions on said elements for engaging the work piece at different locations;
- said assembly being adapted to form said thread by relative movement of said work piece and said assembly of threading elements both rotatively about an axis and at the same time axially;
- said elements being movable axially relative to one another during the rotary and axial movement, to give the thread said varying pitch.
Dependencies are inferred from the claim text.