Pipe cutter

• US 8,266,991 B2
• Filed: 03/14/2008
• Issued: 09/18/2012
• Est. Priority Date: 03/15/2007
• Status: Active Grant

• Current Assignee: Milwaukee Electric Tool Corporation (Techtronic Industries Company Limited)
• Original Assignee: Milwaukee Electric Tool Corporation (Techtronic Industries Company Limited)
• Inventors: Thorson, Troy C., Alberti, Daniel J., Bednar, Thomas R., Scott, John S., Anderson, Scott
• Primary Examiner(s): Peterson, Kenneth E.
• Application Number:
  US12/530,690
• Publication Number:
  US 20100088898A1
• Time in Patent Office: 1,649 Days
• Field of Search: 30 95- 99, 301/01, 82/59, 82/62, 82/64, 82/76, 82/77, 821/00, 82/991, 82/992
• US Class Current: 82/76
• CPC Class Codes: B23D 21/04 Tube-severing machines with rotating tool-carrier
• CPC Class Codes: B23D 21/08 with cutting wheels
• CPC Class Codes: B26D 3/169 Hand held tube cutters
• CPC Class Codes: Y10T 82/16541 Resilient means for tool actuation
• CPC Class Codes: Y10T 82/16918 Spring urged

Abstract

A pipe cutter for cutting a pipe includes a cutting head assembly having a first carriage and a second carriage spaced apart to define a cutting area. The first carriage supports a cutting mechanism, and the second carriage is configured to support a pipe within the cutting area. The carriages have a locked state and an unlocked state such that when the carriages are in the unlocked state, the carriages are movable relative to each other and biased into the cutting area. The pipe cutter also includes a drive assembly configured to rotate the cutting head assembly and a locking mechanism configured for changing the carriages from the unlocked state to the locked state and for holding the carriages in the locked state. The locking mechanism includes an actuation member rotatably coupled to the first carriage.

Claims

1. A pipe cutter for cutting a pipe, the pipe cutter comprising:

a cutting head assembly including a first carriage and a second carriage spaced apart to define a cutting area, the first carriage having a first portion supporting a cutting mechanism and the second carriage configured to support a pipe within the cutting area, wherein the carriages have a locked state and an unlocked state, and

further wherein when the carriages are in the unlocked state, the carriages are movable relative to each other and biased into the cutting area;

a drive assembly configured to rotate the cutting head assembly; and

a locking mechanism configured for changing the carriages from the unlocked state to the locked state and for holding a second portion of the first carriage in a locked state relative to the second carriage, the locking mechanism comprising,

an actuation member rotatably coupled to the second portion of the first carriage, wherein rotation of the cutting head assembly causes rotation of the actuation member relative to the first carriage, and

a locking member configured for engagement with the first carriage and the second carriage upon rotation of the actuation member, wherein engagement of the locking member with the first carriage and the second carriage holds the carriages in the locked state,

wherein the first carriage includes a biasing member between the first portion and the second portion, wherein upon rotation of the cutting head assembly the actuation member rotates relative to the first carriage and deflects the biasing member such that a biasing force acts on the cutting mechanism to cut the pipe.

2. The pipe cutter of claim 1 wherein the cutting mechanism includes a blade.

3. The pipe cutter of claim 1 wherein the second carriage includes a pair of rollers.

4. The pipe cutter of claim 1 wherein the actuation member comprises a cam, the cam including a cam shaft, a lever extending from the cam shaft, and a post positioned at a free end of the lever.

5. The pipe cutter of claim 4, and further comprising a cam actuator fixed relative to the cutting head assembly, wherein the cam actuator engages the post to rotate the cam member as the cutting head assembly rotates.

6. The pipe cutter of claim 1 wherein the locking mechanism further comprises a support member coupled to the second carriage and the locking member engages the support member upon rotation of the actuation member to hold the carriages in the locked state.

7. The pipe cutter of claim 6 wherein the locking member comprises,

a lift member selectively engageable with the actuation member for movement relative to the support member as the actuation member rotates;

and

a locking plate for engaging the support member and the first carriage, wherein the lift member moves the locking plate into engagement with the support member and the first carriage.

8. The pipe cutter of claim 7 wherein the support member includes a plurality of notches, each notch corresponding to a position of the carriages in the locked state.

9. The pipe cutter of claim 8 wherein when the carriages are in the locked state, the locking plate engages one of the plurality of notches to hold the carriages in the corresponding position of the locked state.

10. The pipe cutter of claim 8 wherein each of the positions of the carriages corresponds to a pipe diameter.

11. The pipe cutter of claim 1, wherein in the unlocked state the carriages are configured to receive the pipe within the cutting area.

12. The pipe cutter of claim 1, wherein in the locked state the carriages hold the pipe within the cutting area.

13. The pipe cutter of claim 1, and further comprising a battery-powered drive assembly.

14. The pipe cutter of claim 1, and further comprising a housing containing the cutting head assembly, the housing including a window located in a wall of the housing for viewing the cutting area through the housing.

15. The pipe cutter of claim 1, and further comprising a water-tight seal located between a forward portion of the pipe cutter including the cutting head assembly and a handle portion of the pipe cutter.

16. The pipe cutter of claim 1 wherein the biasing member is a biasing arm having the first portion and the second portion.

17. The pipe cutter of claim 11 wherein the cutting head assembly further comprises:

a spring biasing the second carriage into the cutting area; and

an over-center position for the pipe, the over-center position defined by the cutting mechanism and a support surface of the second carriage,

wherein in the locked state the carriages hold the pipe in the over-center position.

18. The pipe cutter of claim 1 wherein the cutting head assembly rotates in a first direction to change the carriages to the locked state and the cutting head assembly rotates in a second direction to release the carriages to the unlocked state.

19. The pipe cutter of claim 18, and further comprising a release mechanism for releasing the carriages to the unlocked state, the release mechanism including a lever pivotally coupled to a housing of the pipe cutter proximate the cutting head assembly, wherein during rotating of the cutting head assembly in the second direction the actuation member contacts the lever to release the locking member from engagement with the first carriage and the second carriage.

20. The pipe cutter of claim 19 wherein the release mechanism includes a stop boss extending from an outer surface of the cutting head assembly, wherein during rotation of the cutting head assembly in the second direction the stop boss contacts the lever to stop rotation of the cutting head assembly.

21. A pipe cutter for cutting a pipe, the pipe cutter comprising:

a cutting head assembly including,

a first carriage including a biasing arm having a first portion with a cutting mechanism, and having a second portion,

a second carriage spaced apart from the first carriage to define a cutting area, the second carriage including a support surface for supporting a pipe within the cutting area,

an over-center position for the pipe, the over-center position defined by the cutting mechanism and the support surface,

wherein the carriages have an unlocked state for inserting the pipe into the cutting area and a locked state for cutting the pipe,

wherein when the first carriage is in the unlocked state the first carriage is movable relative to the second carriage and is biased into the cutting area, and

a spring biasing the second carriage into the cutting area such that when the second carriage is in the unlocked state, the second carriage is movable relative to the first carriage;

a drive assembly configured to rotate the cutting head assembly; and

a locking mechanism configured for moving the carriages from the unlocked state to the locked state and for holding the carriages in the locked state when the pipe is positioned in the over-center position, the locking mechanism comprising,

an actuation member rotatably coupled to the second portion of the first carriage, wherein rotation of the cutting head assembly causes rotation of the actuation member relative to the first carriage, and

a locking member configured for engagement with the second portion of the first carriage and the second carriage upon rotation of the actuation member, wherein engagement of the locking member locks the second portion of the first carriage and the second carriage together and deflects the biasing arm such that a biasing force acts on the cutting mechanism to cut the pipe.

22. The pipe cutter of claim 21 wherein the cutting mechanism includes a blade.

23. The pipe cutter of claim 21 wherein the support surface of the second carriage includes a pair of rollers.

24. The pipe cutter of claim 21, and further comprising a battery-powered drive assembly.

25. The pipe cutter of claim 21, and further comprising a housing containing the cutting head assembly, the housing including a window located in a wall of the housing for viewing the cutting area through the housing.

26. The pipe cutter of claim 21, and further comprising a water-tight seal located between a forward portion of the pipe cutter including the cutting head assembly and a handle portion of the pipe cutter.

27. The pipe cutter of claim 21, and further comprising:

a handle portion including a first hand grip and a second hand grip; and

a switch assembly positioned on the handle portion between the first hand grip and the second hand grip.

28. The pipe cutter of claim 21 wherein each of the carriages includes a forward angled surface proximate an opening to cutting area, the forward angled surfaces being symmetrical and configured to guide a pipe into the cutting area.

29. The pipe cutter of claim 28 wherein the biasing arm includes a projection opposite the support surface and forward of the over-center position.

30. The pipe cutter of claim 29, wherein each of the carriages includes a rear angled surface rearward of the over-center position, the rear angled surfaces being symmetrical and converging at the rear portion of the cutting area.

31. The pipe cutter of claim 21, wherein the actuation member comprises a cam member, the cam member including a cam shaft, a lever extending from the cam shaft, and a post positioned at a free end of the lever.

32. The pipe cutter of claim 31, and further comprising a cam actuator fixed relative to the cutting head assembly, wherein the cam actuator engages the cam post to rotate the cam member as the cutting head assembly rotates.

33. The pipe cutter of claim 21, wherein the locking mechanism further comprises a support member coupled to the second carriage.

34. The pipe cutter of claim 33, wherein the locking member comprises:

a lift member selectively engageable with the actuation member for movement relative to the support member as the actuation member rotates; and

a locking plate for engaging the support member and the first carriage, wherein the lift member moves the locking plate into engagement with the support member and the first carriage.

35. The pipe cutter of claim 33 wherein the support member includes a plurality of notches, the locking plate engaging one of the plurality of notches when the locking mechanism is in the locked state, each notch corresponding to a position of the carriages in the locked state.

36. The pipe cutter of claim 35 wherein each of the positions of the carriages corresponds to a pipe diameter.