Plunge cutting device and method for pipes

• US 5,314,270 A
• Filed: 04/29/1993
• Issued: 05/24/1994
• Est. Priority Date: 03/20/1992
• Status: Expired due to Term

• Current Assignee: Tri Tool Inc.
• Original Assignee: Darrell G. Stack, Wayne N. Lavancy
• Inventors: Lavancy, Wayne N., Stack, Darrell G.
• Primary Examiner(s): Bishop, Steven C.
• Application Number:
  US08/052,521
• Time in Patent Office: 390 Days
• Field of Search: 82/113, 408/82, 408/113, 408/114, 408/196, 408/197, 408/200, 408/201, 408/203.5, 408/204, 408/206, 408/207, 408/225, 408/1 R, 408/1 BD, 408/713
• US Class Current: 408/1.00R
• CPC Class Codes: B23B 2270/22 Externally located features, machining or gripping of external surfaces machining or gripping of both internal and external surfaces B23B2270/205
• CPC Class Codes: B23B 5/168 with guiding devices
• CPC Class Codes: Y10S 408/713 Tool having detachable cutting edge
• CPC Class Codes: Y10T 408/03 Processes
• CPC Class Codes: Y10T 408/88 including central-lead
• CPC Class Codes: Y10T 408/8923 Removable central lead
• CPC Class Codes: Y10T 408/895 Having axial, core-receiving central portion
• CPC Class Codes: Y10T 82/22 Portable lathe for pipe turning

Abstract

A plunge cutting device for plastic pipe, pipe couplings, plastic flanges and other planar members includes a cylindrical body including slots formed therein, a pilot for guiding the cylindrical body, and cutters adjustably mounted in the slots. A canted relief is formed in the cylindrical body adjoining the leading wall of each slot to facilitate ejection of cut shavings. The pilot may comprise a main pilot and an auxiliary pilot detachably connected to the main pilot. The auxiliary pilot can be replaced with one of a different diameter in accordance with the dimensions of a pipe being processed with the device.

Claims

1. A plunge cutting device comprising:

a cylindrical body having an end wall, a cylindrical wall having a first end with an end face and a second end, the cylindrical wall being jointed to the end wall at the second end and having an inner cylindrical surface and an outer cylindrical surface, at least one slot being formed in the end face and extending axially from the first end of the cylindrical wall;

at least one cutter disposed in one of the slots; and

a pilot for guiding the cylindrical body relative to a tubular member, the pilot comprising a main pilot coaxially secured to the cylindrical body and having a cylindrical outer surface surrounded by and spaced from the inner cylindrical surface of the cylindrical body, and a one-piece auxiliary pilot detachably mounted on the main pilot and having a cylindrical outer surface coaxial with the inner cylindrical surface of the cylindrical body.

2. The plunge cutting device according to claim 1 wherein the main pilot comprises a first cylindrical portion coaxial with the inner cylindrical surface of the cylindrical body and a second portion secured to the first cylindrical portion and having a smaller cross section than the first cylindrical portion, and the auxiliary pilot is secured to the second portion of the main pilot.

3. The plunge cutting device according to claim 2 wherein the auxiliary pilot has an outer diameter at least equal to the first cylindrical portion of the main pilot.

4. The plunge cutting device according to claim 2 wherein the auxiliary pilot has a cavity shaped to fit over the second portion of the main pilot, and the auxiliary pilot can be secured to the second portion of the main pilot with the cavity fitting over the second portion or facing away from the second portion.

5. The plunge cutting device according to claim 1 wherein the pilot includes a plurality of one-piece auxiliary pilots of different outer diameters, each of which can be detachably mounted on the main pilot.

6. The plunge cutting device according to claim 1 wherein the cutter is square.

7. The plunge cutting device according to claim 1 wherein the cutter is rectangular and has lengthwise sides and widthwise sides shorter than the lengthwise sides.

8. The plunge cutting device according to claim 1 wherein each of the slots has a leading wall and at least one relief in the end face of the cylindrical wall outside of the slot, each relief adjoining the leading wall of a slot.

9. The plunge cutting device according to claim 8 wherein each relief is sloped with respect to the end face from the inner surface toward the outer surface of the cylindrical body.

10. The plunge cutting device according to claim 1 wherein the cutter protrudes from the end face of the cylindrical wall from the inner surface to the outer surface of the cylindrical wall.

11. The plunge cutting device according to claim 1 wherein the auxiliary pilot is mounted on and detached from the main pilot by movement of the auxiliary pilot in the axial direction of the main pilot.

12. The plunge cutting device according to claim 2 wherein the second cylindrical portion of the main pilot has an outer end surface abutting against the auxiliary pilot.

13. The plunge cutting device according to claim 1 wherein the auxiliary pilot has an end surface further from the cylindrical body than the main pilot.

14. The plunge cutting device according to claim 1 wherein the auxiliary pilot extends completely around the main pilot.

15. A plunge cutting device comprising:

a cylindrical body having an end wall, a cylindrical wall having a first end with an end face and a second end, the cylindrical wall being jointed to the end wall at the second end and having an inner cylindrical surface and an outer cylindrical surface, at least one slot formed in the end face and extending axially from the first end of the cylindrical wall, each slot having a leading wall and a trailing wall, and at least one relief in the end face outside of each slot, each relief adjoining the leading wall of a slot;

at least one cutter disposed in each slot; and

a pilot for guiding the cylindrical body relative to a tubular member, the pilot being coaxially connected to the cylindrical body and spaced from the inner cylindrical surface of the cylindrical body.

16. A method for cutting a tubular member from an elbow joint using a plunge cutting device including a cylindrical body having an axis and a cylindrical wall, a plurality of cutters mounted in slots in the cylindrical wall, and a pilot coaxially mounted on the cylindrical body, the pilot including a main pilot having a cylindrical portion and an auxiliary pilot coaxially mounted on the main pilot and having a cylindrical outer surface, the method comprising:

inserting the auxiliary pilot into an end of the elbow joint with the cylindrical outer surface of the auxiliary pilot supported by an inner surface of the elbow joint;

rotating the cylindrical body about the axis while urging the cutters against the tubular member to cut into the tubular member to a first depth;

removing the auxiliary pilot from the end of the elbow joint upon reaching the first depth and detaching the auxiliary pilot from the main pilot;

inserting the main pilot into the end of the elbow joint with the cylindrical portion of the main pilot supported by the inner surface of the elbow joint; and

rotating the cylindrical body about the axis while urging the cutters against the tubular member to cut into the tubular member to a second depth greater than the first depth.