Cutting tool assembly

Patent metadata

Field	Value
Publication number	US-12403535-B2
Application number	US-202017779415-A
Country	US
Kind code	B2
Filing date	Sep 3, 2020
Priority date	Nov 22, 2019
Publication date	Sep 2, 2025
Grant date	Sep 2, 2025

Abstract

A cutting tool assembly includes a first tool part and a second tool part. The first tool part has a forward end portion including a cutting edge and a rearward end portion having a conical section and an engagement section. The second tool part includes a conical recess and a clamping device rearwards the conical recess. The clamping device is provided in a transversal cavity of the second tool part and has a first clamp block, a second clamp block and a differential screw engaging the first and second clamp blocks. The first and second clamp blocks engage the engagement section of the first tool part to pull the first tool part into the conical recess when the first and second clamp blocks are moved towards each other by the differential screw protruding rearwards from the first and second clamp blocks.

First claim

The invention claimed is:

1. A cutting tool assembly comprising:
a first tool part having at least one cutting edge; and
a second tool part arranged for releasably holding the first tool part, the first tool part extending along a longitudinal axis, wherein the first tool part includes a forward end portion including the at least one cutting edge and a rearward end portion including a conical section tapering away from the forward end portion, and an engagement section located rearwards the conical section, the second tool part including a conical recess arranged for receiving the conical section of the first tool part, and a clamping device located rearwards the conical recess, the clamping device being provided in a transversal cavity of the second tool part and having a first clamp block, a second clamp block and a differential screw extending along a transversal axis and engaging the first and second clamp blocks, wherein the differential screw is configured to move the first and second clamp blocks in parallel with the transversal axis away from and towards each other, wherein the first and second clamp blocks include a respective engagement surface arranged to engage the engagement section of the first tool part when the conical section is placed in the conical recess in order to pull the first tool part into a holding position in the conical recess when the first and second clamp blocks are moved towards each other, and wherein each of the first and second clamp blocks includes a respective threaded channel extending in parallel with the transversal axis and receiving the differential screw protruding rearwards from the first and second clamp blocks beyond the threaded channels, wherein each of the threaded channels has an elongated opening, which extends in parallel with the transversal axis through a rearward end of the first and second clamp blocks, respectively, and wherein the differential screw protrudes rearwards through the openings.

2. The cutting tool assembly according to claim 1 , wherein, as seen in a plane perpendicular to the transversal axis, each of the threaded channels has a central angle β having a first ray that intersects a first edge of the elongated opening and a second ray that intersects a second edge of the elongated opening, and wherein 180°<β<360°.

3. The cutting tool assembly according to claim 1 , wherein the clamping device includes an elastic retaining ring extending around the second tool part and the first and second clamp blocks, and wherein the retaining ring retains the first and second clamp blocks in the transversal cavity of the second tool part.

4. The cutting tool assembly according to claim 1 , wherein the differential screw includes a first threaded part cooperating with the threaded channel of the first clamp block and a second threaded part cooperating with the threaded channel of the second clamp block, and wherein at least one of the first threaded part and the second threaded part protrudes rearwards from the respective first and second clamp block beyond the respective threaded channel.

5. The cutting tool assembly according to claim 1 , wherein the cutting tool assembly includes a coolant system for the supply of coolant to the cutting edge, wherein the coolant system includes a first central channel through the first tool part and a second central channel through the second tool part, and wherein the clamping device and/or the transversal cavity is configured to permit coolant to flow through the second central channel into the first central channel.

6. The cutting tool assembly according to claim 5 , wherein the differential screw includes a restricted mid portion between the first threaded part and the second threaded part, and wherein the coolant is permitted to flow through the second central channel into the first central channel thereby bypassing the restricted mid portion of the differential screw.

7. The cutting tool assembly according to claim 1 , wherein the engagement section includes a first transversal groove and a second transversal groove, which are separated from and located diametrically opposite to each other and include a respective inclined forward surface turned towards the conical section.

8. The cutting tool assembly according to claim 7 , wherein the first and second clamp blocks include a respective engagement surface engaging a respective one of the inclined forward surfaces in order to pull the first tool part into the holding position in the conical recess when the first and second clamp blocks are moved towards each other.

9. The cutting tool assembly according to claim 7 , wherein each of the first and second transversal grooves has a bottom surface, which is perpendicular to the longitudinal axis when seen in a direction from the first transversal groove to the second transversal groove.

10. The cutting tool assembly according to claim 9 , wherein the bottom surface is convexly curved.

11. The cutting tool assembly according to claim 10 , wherein the bottom surface has a radius of curvature being longer than a smallest radial distance from the bottom line to the longitudinal axis.

12. The cutting tool assembly according to claim 1 , wherein the engagement section includes two inclined rearward surfaces turned away from the conical section and configured to be engaged by a respective forward surface of the first and second clamp blocks in order to push the first tool part out of the holding position in the conical recess when the first and second clamp blocks are moved away from each other.

13. The cutting tool assembly according to claim 1 , wherein the conical section of the rearward end portion of the first tool part has a cone angle α, and wherein 0.5°≤α≤10°.

14. The cutting tool assembly according to claim 1 , wherein the rearward end portion of the first tool part includes at least one axial groove extending along the conical section, wherein the conical recess of the second tool part includes at least one axial groove, and wherein a pin is provided in the at least one axial groove of the second tool part and arranged to co-operate with the at least one axial groove of the first tool part to permit torque transmission between the second tool part and the first tool part when the first tool part is mounted in the second tool part.

15. The cutting tool assembly according to claim 1 , wherein the forward end portion of the first tool part is integrally formed with the rearward end portion of the first tool part.

16. The cutting tool assembly according to claim 1 , wherein the first tool part includes a reamer.

17. The cutting tool assembly according to claim 1 , wherein the second tool part includes at least one cutting edge.

18. The cutting tool assembly according to claim 1 , wherein the cutting tool assembly is a rotating cutting tool assembly.

Assignees

• Seco Tools Ab

Inventors

• Rimet Lilian

Classifications

• B23D77/006

  with means for lubricating or cooling · CPC title

• B23B31/008

  with arrangements for transmitting torque · CPC title

• B23B2231/24

  Cooling or lubrication means · CPC title

• B23B29/046

  with an intermediary toolholder · CPC title

• B23B2260/056

  Differential screw threads · CPC title