Machine tool having a balancing device

Patent metadata

Field	Value
Publication number	US-2022126417-A1
Application number	US-202017428141-A
Country	US
Kind code	A1
Filing date	Jan 31, 2020
Priority date	Feb 7, 2019
Publication date	Apr 28, 2022
Grant date	—

Abstract

A machine tool having a drivetrain, which includes a tool shaft rotatably mounted on a drive support by means of a bearing assembly and a tool holder arranged on the tool shaft, wherein the tool shaft is rotationally drivable by a drive motor of the machine tool around a rotational axis, and wherein a balancing device is arranged on the tool shaft, which includes a guide body having at least one orbital path extending around the rotational axis and at least one balancing body movably mounted in the orbital path.

First claim

1 . A machine tool, having a drivetrain, which includes a tool shaft rotatably mounted on a drive support by means of a bearing assembly and a tool holder, arranged on the tool shaft, for a disk-like working tool, wherein the tool shaft is rotationally drivable by a drive motor of the machine tool around a rotational axis, and wherein a balancing device is arranged on the tool shaft, which includes a guide body having at least one orbital path extending around the rotational axis and at least one balancing body movably mounted in the orbital path, and wherein the at least one orbital path arranged on the guide body comprises a first orbital path having a first radial distance to the rotational axis and at least one second orbital path, which is at a longitudinal distance with respect to the rotational axis in relation to the first orbital path, and which has a greater second radial distance to the rotational axis than the first radial distance and is separated from the first orbital path, so that the balancing bodies arranged in the respective orbital path are held so they are non-adjustable between the orbital paths and/or in a cage like manner in their respective orbital path.

2 . The machine tool as claimed in claim 1 , wherein the guide body includes a main body, on which the first and at least one second orbital path are integrally formed.

3 . The machine tool as claimed in claim 2 , wherein the first and the at least one second orbital path are produced by cutting machining of the main body, wherein the main body remains on a workpiece holder after completion of the production of the first orbital path until the beginning of the production of the at least second orbital path.

4 . The machine tool as claimed in claim 1 , wherein a main body of the guide body integrally including the orbital paths, and the tool shaft are integral.

5 . The machine tool as claimed in claim 4 , wherein the main body remains on a workpiece holder to produce the tool shaft and the first orbital path and/or the at least second orbital path.

6 . The machine tool as claimed in claim 1 , wherein the guide body includes a cover, using which the first orbital path and/or the second orbital path are closed.

7 . The machine tool as claimed in claim 6 , wherein the cover closes at least one orbital path of the guide body parallel to the rotational axis and/or on the radial inside with respect to the rotational axis.

8 . The machine tool as claimed in claim 1 , wherein at least one orbital path of the guide body is completely closed in relation to the other orbital path or the other orbital paths of the guide body.

9 . The machine tool as claimed in claim 1 , wherein different damping fluids are arranged in at least two orbital paths of the guide body, and/or wherein, of at least two orbital paths of the guide body, only one orbital path has a damping fluid.

10 . The machine tool as claimed in claim 1 , wherein surfaces, which mount the respective at least one balancing body, of the first orbital path and the at least one second orbital path have different sliding properties and/or different geometries.

11 . The machine tool as claimed in claim 1 , wherein the first and the at least one second orbital path comprise or form at least two orbital paths, in which balancing bodies are arranged having different geometry and/or different weight and/or different sliding properties and/or in different numbers and/or made of different materials.

12 . The machine tool as claimed in claim 1 , wherein the orbital path having the greatest radial distance to the rotational axis is closer to the tool holder and/or to the working tool than the at least one orbital path having a lesser radial distance is to the rotational axis.

13 . The machine tool as claimed in claim 1 , wherein a longitudinal distance with respect to the rotational axis between the orbital paths of the balancing device is at most three times as large as a longitudinal extension or height of an orbital path with respect to the rotational axis.

14 . The machine tool as claimed in claim 1 , wherein a longitudinal distance with respect to the rotational axis between the orbital paths of the balancing device is at minimum one-half, the longitudinal extension of the height of an orbital path with respect to the rotational axis.

15 . The machine tool as claimed in claim 1 , wherein an inner radius of the at least one second orbital path is greater than an outer radius of the first orbital path or approximately corresponds to the outer radius of the first orbital path.

16 . The machine tool as claimed in claim 1 , wherein the guide body includes an outer circumferential wall, which extends around the rotational axis, and which has a greater diameter in a region closer to the tool holder than in a region which has a greater distance to the tool holder, and/or wherein the guide body has the form of a bell or a truncated cone.

17 . The machine tool as claimed in claim 1 , wherein the guide body is a part of a fan wheel and/or wherein fan blades are arranged, on the guide body.

18 . The machine tool as claimed in claim 1 , wherein the tool holder has an eccentricity with respect to the rotational axis and/or is arranged on an eccentric bearing having an eccentricity with respect to the rotational axis, so that the tool holder is eccentrically mounted in relation to the rotational axis.

19 . The machine tool as claimed in claim 1 , wherein a bearing, using which the tool holder is rotatably mounted relative to the rotational axis, is arranged in an interior of the guide body.

20 . The machine tool as claimed in claim 1 , wherein the guide body is arranged adjacent to the bearing assembly rotatably mounting the tool shaft on the drive support.

21 . The machine tool as claimed in claim 1 , wherein the guide body is held on the tool shaft between two rotational bearings, using which the tool shaft is rotatably mounted on the drive support.

22 . The machine tool as claimed in claim 1 , wherein no bearing of the bearing assembly mounting the tool shaft on the drive support is arranged between the orbital paths of the balancing device with respect to the longitudinal extension of the rotational axis.

23 . The machine tool as claimed in claim 1 , wherein the guide body includes a bearing receptacle for a bearing of the bearing assembly and/or wherein a bearing of the bearing assembly which is arranged on the tool shaft is arranged in an interior of the guide body and/or wherein the guide body has the shape of a bell, in the interior of which the bearing is arranged.

24 . The machine tool as claimed in claim 1 , wherein the orbital paths are circular paths, which extend at a radial distance around a center axis, wherein the center axis and the rotational axis of the tool shaft are coaxial.

25 . The machine tool as claimed in claim 24 , wherein the radial distance of the first orbital path and/or the at least one second orbital path varies by at most 0.05%, of its length and/or has an eccentricity of the first orbital path and/or the at least one second orbital path with respect to the rotational axis of the motor shaft of at most 0.05%.

26 . The machine tool as claimed in claim 1 , wherein a balancing mass eccentric in relation to the rotational axis is arranged fixedly on the guide body.

27 . The machine tool as claimed in claim 26 , wherein the balancing m

Assignees

• Festool Gmbh

Inventors

• Ruhland Harald

Classifications

• B24B41/042

  Balancing mechanisms · CPC title

• B24B47/12

  by mechanical gearing or electric power (B24B47/16 takes precedence) · CPC title

• B24B23/04

  with oscillating grinding tools; Accessories therefor · CPC title

• F16F15/36

  operating automatically {, i.e. where, for a given amount of imbalance, there is movement of masses until balance is achieved (damping vibrations of washing machines by displacing, supplying or ejecting a material, e.g. liquid, into or from counterbalancing pockets D06F37/245)} · CPC title

• B24B23/02 Primary

  with rotating grinding tools; Accessories therefor · CPC title