Internal milling cutter

Patent metadata

Field	Value
Publication number	US-11311950-B2
Application number	US-201716469190-A
Country	US
Kind code	B2
Filing date	Sep 22, 2017
Priority date	Dec 14, 2016
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

Abstract

An internal milling cutter includes a carrier disk having a centre axis defining an axis of rotation of the milling cutter, a plurality of separated tool holder segments removably mounted at the inner circumference of the carrier disk, and at least one clamp for each tool holder segment mounted either on the carrier disk or on the tool holder segment. Each of the tool holder segments at its inner circumference includes at least one cutting insert seat with a mounting element for a cutting insert or at least one cutting edge. The clamp is located and arranged such that it generates a force in the axial direction pressing the axial contact surface of the tool holder segment onto the axial abutment surface of the carrier disk, and the clamp is mounted movably in a radial direction of the carrier disk between a locking position and a releasing position.

First claim

The invention claimed is:

1. An internal milling cutter comprising:
a ring shaped carrier disk having an outer circumference, an inner circumference, a center axis defining an axis of rotation of the milling cutter, and a plurality of separated tool holder segments removably mounted at the inner circumference of the carrier disk; and
at least one clamp for each of the plurality of tool holder segments mounted either on the carrier disk or on the tool holder segment, wherein the plurality of tool holder segments together form a ring, and wherein each of the plurality of tool holder segments at its inner circumference includes at least one cutting insert seat with a mounting element for a cutting insert or at least one cutting edge, the carrier disk including an axial abutment surface for each of the plurality of tool holder segments, the axial abutment surface supporting each of the plurality of tool holder segments in an axial direction of the carrier disk, each of the plurality of tool holder segments including an axial contact surface in engagement with the axial abutment surface of the carrier disk, and wherein the clamp is located and arranged such that it generates a force in the axial direction pressing the axial contact surface of the tool holder segment onto the axial abutment surface of the carrier disk, and wherein the clamp is mounted movably in a radial direction of the carrier disk between a locking position and a releasing position, wherein in the locking position the clamp is in engagement with the carrier disk and the tool holder segment preventing an axial separation of the carrier disk and the tool holder segment, and wherein in the releasing position the clamp allows a separation of the carrier disk and the tool holder segment in the axial direction of the carrier disk,
wherein each of the plurality of tool holder segments and the carrier disk include complementary protrusions and recesses and in engagement with each other in order to provide a transfer of a torque from the carrier disk onto the plurality of tool holder segments, and
wherein each recess and each protrusion has two side surfaces extending radially such that the two side surfaces taper towards the center axis of the carrier disk enabling a radial expansion of each of the plurality of tool holder segments.

2. The milling cutter according to claim 1 , wherein the clamp is spring biased towards the releasing position.

3. The milling cutter according to claim 1 , wherein the clamp is slidably mounted.

4. The milling cutter according to claim 1 , wherein the clamp is slidably mounted in a guiding groove extending in a radial direction of the carrier disk, wherein the groove is open towards the outer circumference of the carrier disk.

5. The milling cutter according to claim 1 , wherein the clamp is mounted by a screw and wherein the screw is in engagement with a nut being slidably mounted in a guiding groove extending in a radial direction on the carrier disk or on each of the plurality of tool holder segments.

6. The milling cutter according to claim 1 , wherein the clamp and either the carrier disk or each of the plurality of tool holder segments includes markings denoting the locking position and the releasing position of the clamp.

7. The milling cutter according to a claim 1 , wherein the clamp is formed by a shim and wherein in a surface of the carrier disk or in a surface of each of the plurality of tool holder segments, a pocket is formed, wherein the shim in the locking position engages with the pocket.

8. The milling cutter according to claim 1 , wherein one of the two side surfaces lies in a plane tilted with respect to the center axis to facilitate insertion of the complementary projection into the recess.

9. The milling cutter according to claim 1 , wherein the clamps are located at same circumferential positions as the complementary protrusions and recesses.

10. The milling cutter according to claim 1 , wherein the carrier disk includes a radial abutment surface pointing radially inwardly for each of the plurality of tool holder segments and wherein each of the plurality of tool holder segments includes a radial contact surface pointing radially outwardly, and wherein the carrier disk and the plurality of tool holder segments are arranged such that there is a gap between the radial abutment surface of the carrier disk and the radial contact surface of each of the plurality of tool holder segments at room temperature allowing for a thermal expansion of the plurality of tool holder segments in a radial direction.

11. The milling cutter according to claim 1 , wherein each of the plurality of tool holder segments has a latch being spring biased in a direction perpendicular to the center axis, wherein the latch is in engagement with a recess at the carrier disk.

12. The milling cutter according to claim 11 , wherein the carrier disk includes a guiding pin oriented in an axial direction, wherein the recess is located in the guiding pin, and wherein the guiding pin of the carrier disk has an extension in the axial direction of the carrier disk such that when mounting each of the plurality of tool holder segments on the carrier disk each of the plurality of tool holder segments and the guiding pin come into engagement with each other before the axial abutment surface and the axial contact surface come into engagement with each other.

13. A mounting device comprising:
an internal milling cutter according to claim 1 ;
a basic body with a mounting surface arranged to accommodate the plurality of tool holder segments;
a handle attached to the basic body; and
at least one locking element for each of the plurality tool holder segments protruding from the mounting surface, wherein each of the plurality of tool holder segments has a hole to accommodate and mount the locking element.

Assignees

• Sandvik Intellectual Property

Inventors

• Knecht Stefan
• Lohr Rudolf

Classifications

• B23C5/08

  Disc-type cutters · CPC title

• B23C5/2234 Primary

  for plate-like cutting inserts fitted on a ring or ring segment · CPC title

• B23C2210/503

  mounted internally on the cutter · CPC title

• B23C2220/68

  Whirling · CPC title

• B23C2210/66

  Markings, i.e. symbols or indicating marks · CPC title