Cams for pipe grooving device
A device for forming circumferential grooves in pipe elements uses multiple geared cam bodies mounted on a carriage which rotates about a fixed pinion. The gears engage with the pinion which causes the geared cam bodies to rotate relative to the carriage. Traction surfaces and cam surfaces on the cam bodies traverse the outer surface of the pipe element and impress a circumferential groove therein. Each cam surface has a region of increasing radius and may have a region of constant radius. Second cam surfaces, positioned in spaced relation axially to the first cam surfaces, may also extend around the cam bodies. The second cam surfaces have a constant radius and limit flare of the pipe element.
1. A plurality of cams for cold working a pipe element, said cams being rotated circumferentially about said pipe element, each said cam comprising:
a cam body having an axis of rotation;
a first cam surface extending around said cam body, said first cam surface comprising a first region of increasing radius and a first discontinuity of said first cam surface;
a second cam surface extending around said cam body and positioned in spaced relation along said axis of rotation to said first cam surface; wherein
moving around an outer circumference of said cam body, said second cam surface has a consistent spacing from said first cam surface along said axis of rotation.
2. The cam according to claim 1 , wherein said second cam surface comprises a second region of increasing radius and a second discontinuity of said second cam surface, said second discontinuity being aligned with said first discontinuity.
3. The cam according to claim 2 , wherein said second cam surface has a region of constant radius positioned adjacent to said second discontinuity.
4. The cam according to claim 2 , wherein said second discontinuity is circumferentially aligned with said second region of increasing radius.
5. The cam according to claim 1 , wherein said first cam surface has a region of constant radius positioned adjacent to said first discontinuity.
6. The cam according to claim 1 , wherein said second cam surface has a constant radius.
7. The cam according to claim 1 , further comprising a traction surface extending around said cam body, said traction surface having a gap therein, said gap being aligned axially with said first discontinuity.
8. The cam according to claim 7 , wherein said traction surface comprising a plurality of projections extending outwardly therefrom.
9. The cam according to claim 7 , wherein said first cam surface is positioned between said traction surface and said second cam surface.
10. The cam according to claim 9 , further comprising a gear mounted on said cam body, said gear being arranged coaxially with said axis of rotation.
11. The cam according to claim 10 , wherein said first and second cam surfaces are positioned between said traction surface and said gear.
12. The cam according to claim 1 , further comprising a gear mounted on said cam body, said gear being arranged coaxially with said axis of rotation.
13. The cam according to claim 1 , wherein said first discontinuity is circumferentially aligned with said first region of increasing radius.
14. The cam according to claim 1 , wherein said first cam surface extends around said outer circumference at a first position along said axis of rotation.
15. The cam according to claim 14 , wherein said second cam surface extends around said circumference at a second position along said axis of rotation, wherein said second position is spaced from said first position.
16. A plurality of cams for cold working a pipe element, said cams being rotated circumferentially about said pipe element, each said cam comprising:
a cam body having an axis of rotation;
a first cam surface extending around said cam body, said first cam surface comprising a first region of increasing radius and a first discontinuity of said first cam surface, said first discontinuity being circumferentially aligned with said first region of increasing radius;
a second cam surface extending around said cam body and positioned in spaced relation along said axis of rotation to said first cam surface.
17. The cam according to claim 16 , wherein said second cam surface comprises a second region of increasing radius and a second discontinuity of said second cam surface, said second discontinuity being aligned with said first discontinuity.
18. The cam according to claim 16 , wherein said first cam surface has a region of constant radius positioned adjacent to said first discontinuity.
19. The cam according to claim 16 , wherein said second cam surface has a constant radius.
20. The cam according to claim 16 , further comprising a traction surface extending around said cam body, said traction surface having a gap therein, said gap being aligned axially with said first discontinuity.