# US 2023/0264388 A1 · Washers for Rotatable Cutting Tools > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0264388 A1 - Document ID: US20230264388A1 - Status: Published application - Kind: A1 - Application number: 17/676,570 - Filed: 2022-02-21 - Published: 2023-08-24 - Earliest claimed: 2022-02-21 - Assignees: Kennametal Inc. - Applicants: Kennametal Inc. - Inventors: James R. Geyer; Arkadiusz Dlugosz; Thomas J. Long, II - Web page: https://patentgrep.com/patent/US20230264388A1 ## CPC - B28D 1/186: {Tools therefor, e.g. having exchangeable cutter bits (B28D1/181 takes precedence; bits for picks or pick-holders for mining or quarrying E21C35/18)} - B28D 1/188: {with exchangeable cutter bits or cutter segments} - E21C 35/18: Mining picks; Holders therefor (planing knives E21C27/44) - B28D: WORKING STONE OR STONE-LIKE MATERIALS - E21C: MINING OR QUARRYING ## Abstract The present invention provides rotatable cutting tools having washers with changing thicknesses. One side of the washer has a tapered surface that increases the thickness of the washer from the inner radius towards the outer radius, resulting in a thicker portion at the outer edge of the washer. The rotatable cutting tool may also have a bit with a tapered surface. The tapered surface of the bit may be structured and arranged to engage with the tapered surface of the washer. The rotatable cutting tool may also include a holder such that the assembled rotatable cutting tool includes the washer between the bit and the holder with the bit inserted into the holder and washer. ## Claims ### Claim 1 A rotatable cutting tool comprising a rotatable bit and a washer, wherein: the rotatable bit comprises: a bit head including a collar centered on a central longitudinal axis; and a generally cylindrical shank extending rearwardly along the longitudinal axis from a rear of the collar; and the washer comprises: an annular flange centered around the longitudinal axis comprising an annular flange outer diameter, an annular flange inner diameter, a washer front face, and a washer rear face opposite the washer front face; and a central hole extending through the annular flange centered around the longitudinal axis comprising a central hole outer diameter, wherein the washer rear face comprises a washer rear surface substantially perpendicular to the longitudinal axis, and the washer front face comprises a tapered front surface arranged at a slant angle As measured from a direction perpendicular to the longitudinal axis such that the annular flange comprises an inner washer thickness TI, an outer washer thickness TO radially outward from the inner washer thickness TI, and the outer washer thickness TO is greater than the inner washer thickness TI. ### Claim 2 (depends on 1) The rotatable cutting tool of claim 1, wherein the washer rear face surface of the washer is within ± 3° from being 90° to the longitudinal axis. ### Claim 3 (depends on 1) The rotatable cutting tool of claim 1, wherein the slant angle As is at least 1°. ### Claim 4 (depends on 1) The rotatable cutting tool of claim 1, wherein the slant angle As is from 2° to 30° and is greater than any deviation of the washer rear face surface from being 90° to the longitudinal axis. ### Claim 5 (depends on 1) The rotatable cutting tool of claim 1, wherein the outer washer thickness TO is at least 5% greater than the inner washer thickness TI. ### Claim 6 (depends on 1) The rotatable cutting tool of claim 1, wherein the washer front face comprises a planar surface between the annular flange outer diameter and the slanted surface, and the planar surface is perpendicular to the longitudinal axis. ### Claim 7 (depends on 1) The rotatable cutting tool of claim 1, wherein the rear of the collar comprises a collar conical surface tapered at a collar angle AC radially inward and rearwardly from an outer diameter of the collar. ### Claim 8 (depends on 7) The rotatable cutting tool of claim 7, wherein the slant angle As is greater than or equal to the collar angle AC. ### Claim 9 (depends on 7) The rotatable cutting tool of claim 7, wherein the collar angle AC is from 2° to 30°. ### Claim 10 A cutting tool washer for use with a cutting tool bit, the washer comprising: an annular flange centered around the longitudinal axis comprising an annular flange outer diameter, an annular flange inner diameter, a washer front face, and a washer rear face opposite the washer front face; and a central hole extending through the annular flange centered around the longitudinal axis comprising a central hole outer diameter, wherein the washer rear face comprises a washer rear surface substantially perpendicular to the longitudinal axis, and the washer front face comprises a tapered front surface arranged at a slant angle As measured from a direction perpendicular to the longitudinal axis such that the annular flange comprises an inner washer thickness TI, an outer washer thickness TO radially outward from the inner washer thickness TI, and the outer washer thickness TO is greater than the inner washer thickness TI. ### Claim 11 (depends on 10) The rotatable cutting tool of claim 10, wherein the washer rear face surface of the washer is within ± 3° from being 90° perpendicular to the longitudinal axis. ### Claim 12 (depends on 10) The cutting tool washer of claim 10, wherein the slant angle As is at least 1°. ### Claim 13 (depends on 10) The cutting tool washer of claim 10, wherein the slant angle As is from 2° to 30° and is greater than any deviation of the washer rear face surface from being 90° perpendicular to the longitudinal axis. ### Claim 14 (depends on 10) The cutting tool washer of claim 10, wherein the outer washer thickness TO is at least 5% greater than the inner washer thickness TI. ### Claim 15 (depends on 10) The cutting tool washer of claim 10, wherein the outer washer thickness TO is from 40% to 60% greater than the inner washer thickness TI. ### Claim 16 (depends on 10) The cutting tool washer of claim 10, wherein the washer front face comprises a planar surface between the annular flange outer diameter and the slanted surface, and the planar surface is perpendicular to the longitudinal axis. ### Claim 17 (depends on 16) The cutting tool washer of claim 16, wherein the washer front face comprises a tapered front transition edge between the planar surface and the slanted surface comprising a front transition edge diameter at least 5% less than the annular flange outer diameter. ### Claim 18 (depends on 17) The cutting tool washer of claim 17, wherein the front transition edge diameter is at least 20% greater than the annular flange inner diameter. ### Claim 19 A rotatable bit comprising: a bit head including a collar centered on a central longitudinal axis; and a generally cylindrical shank extending rearwardly along the longitudinal axis from a rear of the collar wherein the rear of the collar comprises a collar conical surface tapered at a collar angle AC radially inward and rearwardly from an outer diameter of the collar. ### Claim 20 (depends on 19) The bit of claim 19, wherein the collar angle AC is from 2° to 30°.