# US 2014/0190285 A1 · Oscillatingly Driven Power Tools With Toothed Belt Drive > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0190285 A1 - Document ID: US20140190285A1 - Status: Published application - Kind: A1 - Application number: 14/149,446 - Filed: 2014-01-07 - Published: 2014-07-10 - Earliest claimed: 2013-01-07 - Assignees: C. & E. Fein GmbH - Inventors: Joachim Clabunde - Web page: https://patentgrep.com/patent/US20140190285A1 ## CPC - F16H 19/08: for interconverting rotary motion and oscillating motion - B24B 23/03: the tool being driven in a combined movement - B24B 23/04: with oscillating grinding tools; Accessories therefor - B24B 41/007: {Weight compensation; Temperature compensation; Vibration damping} - B24B 47/12: by mechanical gearing or electric power (B24B47/16 takes precedence) - B25F 5/00: Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for - Y10T 74/18152: Belt or chain carried member - F16H: GEARING - B24B: MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING (grinding of gear teeth B23F, of screw-threads B23G1/36; by electro-erosion B23H; abrasive or related blasting B24C; tools for grinding, buffing or sharpening B24D; polishing compositions C09G1/00; abrasives C09K3/14; electrolytic etching or polishing C25F3/00; grinding arrangements for use on assembled railway tracks E01B31/17); DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS - B25F: COMBINATION OR MULTI-PURPOSE TOOLS NOT OTHERWISE PROVIDED FOR; DETAILS OR COMPONENTS OF PORTABLE POWER-DRIVEN TOOLS NOT PARTICULARLY RELATED TO THE OPERATIONS PERFORMED AND NOT OTHERWISE PROVIDED FOR {(machines or arrangements of machines for performing specified combinations of different metal-working operations not covered by a single other subclass B23P23/00 and subgroups)} - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract The invention discloses an oscillatingly driven power tool, having a motor shaft that can be driven rotationally by a motor and that is coupled via a toothed-belt drive and an eccentric coupling drive to a tool spindle, for the purpose of driving the latter. ## Claims ### Claim 1 An oscillatingly driven power tool, comprising: a motor having a motor shaft driven rotatingly by said motor; a tool spindle; a transmission being configured as a toothed-belt drive; an eccentric coupling drive comprising an eccentric pin and an eccentric lever for driving said tool spindle, said toothed-belt comprising a toothed-belt being driven by said motor spindle and driving said eccentric pin; and an eccentric lever mounted pivotably at a first end thereof, being driven by said eccentric pin at a second end thereof, said eccentric lever driving said tool spindle about a longitudinal axis thereof oscillatingly in a first alternating direction opposite to a second alternation direction in which said eccentric lever is driven. ### Claim 2 (depends on 1) The power tool of claim 1, wherein said toothed-belt drive is lubricated. ### Claim 3 (depends on 1) The power tool of claim 1, wherein said toothed-belt drive has a reduction ratio in the range from 1:2 to 1:5. ### Claim 4 (depends on 1) The power tool of claim 1, wherein said toothed-belt drive has a reduction ratio in the range from 1:2.5 to 1:3.2. ### Claim 5 An oscillatingly driven power tool, comprising: a motor having a motor shaft rotatingly driven by said motor; a tool spindle; an eccentric coupling drive comprising an eccentric pin supported on an eccentric shaft and an eccentric lever for driving said tool spindle oscillatingly about a longitudinal axis thereof; a transmission being configured as a toothed-belt drive comprising a toothed-belt engaging a first belt wheel being driven by said motor shaft and a second belt wheel driving said eccentric shaft; wherein said eccentric pin, together with an eccentric bearing held thereon, are supported on said eccentric shaft; and wherein said second belt wheel comprises a mass compensation for compensating any imbalance caused by said eccentric pin and said eccentric bearing. ### Claim 6 (depends on 5) The power tool of claim 5, wherein said second belt wheel, for effecting said mass compensation, comprises a cutout on a side on which said eccentric pin is disposed. ### Claim 7 (depends on 5) The power tool of claim 5, wherein said toothed-belt drive is lubricated. ### Claim 8 (depends on 5) The power tool of claim 5, wherein said toothed-belt drive has a reduction ratio in the range from 1:2 to 1:5. ### Claim 9 (depends on 5) The power tool of claim 5, wherein said toothed-belt drive has a reduction ratio in the range from 1:2.5 to 1:3.2. ### Claim 10 (depends on 5) The power tool of claim 5, wherein said eccentric lever further comprises a first end engaging said eccentric bearing and a second end being pivotable about an eccentric lever shaft. ### Claim 11 (depends on 10) The power tool of claim 10, further comprising an oscillating lever having a first end and a second end, said first end of said oscillating lever engaging said eccentric lever shaft rotatably, said second end of said oscillating lever being fixed to said tool spindle for driving said tool spindle oscillatingly. ### Claim 12 (depends on 11) The power tool of claim 11, further comprising a bearing axis about which said oscillating lever is supported pivotably. ### Claim 13 (depends on 12) The power tool of claim 12, wherein said bearing axis is arranged between said tool spindle and said eccentric lever axis. ### Claim 14 (depends on 10) The power tool of claim 10, wherein said eccentric coupling drive further comprises a counterweight being driven by said eccentric lever. ### Claim 15 (depends on 14) The power tool of claim 14, wherein said counterweight is arranged at said first end of said eccentric lever. ### Claim 16 (depends on 14) The power tool of claim 14, further comprising a transmission housing, wherein said transmission and said eccentric coupling drive extend, and a machine housing enclosing said transmission housing, wherein said counterweight is arranged outside of said transmission housing but inside of said machine housing. ### Claim 17 An oscillatingly driven power tool, comprising: a motor having a motor shaft driven rotatingly by said motor; a tool spindle; a transmission being configured as a toothed-belt drive; and an eccentric coupling drive being driven by said motor shaft and driving said tool spindle oscillatingly about a longitudinal axis thereof. ### Claim 18 (depends on 17) The power tool of claim 17, wherein said toothed-belt drive comprises a toothed-belt engaging a first belt wheel being driven by said motor shaft, and further engaging a second belt wheel driving said eccentric coupling drive. ### Claim 19 (depends on 18) The power tool of claim 18, wherein said eccentric coupling drive comprises an eccentric pin being driven by said second belt wheel, and an eccentric bearing arranged on said eccentric pin, said eccentric bearing being engaged by an eccentric lever oscillatingly driving said tool spindle. ### Claim 20 (depends on 19) The power tool of claim 19, further comprising an eccentric shaft whereon said eccentric pin, together with said eccentric bearing held thereon, and said second belt wheel are arranged, said second belt wheel further comprising a mass compensation compensating any imbalance caused by said eccentric pin and said eccentric bearing.