Oscillating mechanism for a power tool

Patent metadata

Field	Value
Publication number	US-10883579-B2
Application number	US-201415103989-A
Country	US
Kind code	B2
Filing date	Dec 4, 2014
Priority date	Dec 20, 2013
Publication date	Jan 5, 2021
Grant date	Jan 5, 2021

Abstract

An oscillating power tool includes a drive motor (M) producing rotary motion and an oscillating mechanism ( 30 ) for converting the motor rotary motion to an oscillatory side-to-side movement. The oscillating mechanism ( 30 ) includes a link ( 32 ) driven by an eccentric shaft ( 16 ) of the motor (M), a drive arm ( 40 ) that drives the hub ( 45 ) of the working tool (B) in oscillating motion, and a bearing arrangement ( 37 ) between the drive arm ( 40 ) and the link ( 32 ) that isolates relative rotation and translation between the components while still imparting an oscillatory motion to the drive arm ( 40 ).

First claim

What is claimed is:

1. A power tool comprising:
a drive motor having an eccentric drive shaft with an axis of rotation;
a tool holder adapted to support a working tool for oscillating rotational motion; and
an oscillating mechanism disposed between said eccentric drive shaft and said tool holder, said oscillating mechanism including:
an elongated link mounted at one end thereof on said eccentric drive shaft for eccentric movement upon rotation of said drive shaft about said axis of rotation and including on an opposite end thereof a roller bearing having a loose fit with a small amount of play between an inner race and rollers of the bearing, and/or between the rollers and an outer race of the bearing in a radial direction relative to said axis of rotation of said drive shaft; and

an elongated drive arm having;
a first end coupled to said roller bearing of said link in a manner to isolate relative rotation and translation between said link and said drive arm while still imparting an oscillatory motion in one direction to said drive arm; and
a second end engaged to said tool holder to transfer the oscillatory motion to oscillating rotational motion of said tool holder.

2. The power tool of claim 1 , wherein:
said link includes an upper link mounted on said eccentric drive shaft and a lower link offset from said upper link, said lower link defining a cylindrical opening; and
said second end of said drive arm is a spherical end slidably disposed within said cylindrical opening to permit relative rotation and axial translation between said drive arm and said lower link.

3. The power tool of claim 2 , wherein said lower link includes a cylindrical bushing defining said cylindrical opening.

4. The power tool of claim 2 , wherein said lower link includes said roller bearing disposed in said cylindrical opening.

5. The power tool of claim 2 , wherein said upper link includes a bearing between said upper link and said eccentric drive shaft.

6. The power tool of claim 2 , further comprising a counterweight mounted on said eccentric shaft opposite said lower link.

7. The power tool of claim 1 , wherein:
said tool holder includes a central hub supporting the working tool; and
said first end of said drive arm includes a threaded shaft extending through said central hub and a threaded nut for engaging the threaded shaft to fix said drive arm to said central hub.

8. The power tool of claim 1 , wherein:
said drive motor defines a longitudinal axis;
said eccentric drive shaft includes an eccentric portion offset from said longitudinal axis; and
said link is mounted on said eccentric portion.

9. The power tool of claim 8 , wherein:
said eccentric drive shaft includes an end portion aligned with said longitudinal axis, with said eccentric portion between said motor and said end portion; and
the power tool includes a housing defining a bearing support for supporting said end portion of said eccentric drive shaft.

10. A power tool comprising:
a drive motor having an eccentric drive shaft;
a tool holder adapted to support a working tool for oscillating rotational motion; and
an oscillating mechanism disposed between said eccentric drive shaft and said tool holder, said oscillating mechanism including:
a link mounted on said eccentric drive shaft for eccentric movement upon rotation of said drive shaft; and
an elongated drive arm having;
a first end coupled to said link in a manner to isolate relative rotation and translation between said link and said drive arm while still imparting an oscillatory motion in one direction to said drive arm; and
a second end engaged to said tool holder to transfer the oscillatory motion to oscillating rotational motion of said tool holder, wherein

the drive shaft defines an axis along the length of said drive shaft;
the drive motor defines a longitudinal axis parallel to said axis of the drive shaft;
said tool holder is supported along said longitudinal axis; and
said elongated drive arm is arranged at an angle between said link and said tool holder, said angle being non-parallel and non-perpendicular to said longitudinal axis.

11. A power tool comprising:
a drive motor having an eccentric drive shaft;
a tool holder adapted to support a working tool for oscillating rotational motion; and
an oscillating mechanism disposed between said eccentric drive shaft and said tool holder, said oscillating mechanism including:
a link mounted on said eccentric drive shaft for eccentric movement upon rotation of said drive shaft; and
an elongated drive arm having;
a first end coupled to said link in a manner to isolate relative rotation and translation between said link and said drive arm while still imparting an oscillatory motion in one direction to said drive arm; and
a second end engaged to said tool holder to transfer the oscillatory motion to oscillating rotational motion of said tool holder, wherein

said eccentric drive shaft includes two eccentric portions;
said link is mounted to one of said two eccentric portions; and
a second link is mounted to the other of said two eccentric portions, said second link coupled to a second drive arm for another working tool.

12. An oscillating mechanism for a power tool, the oscillating mechanism engaged between an eccentric drive shaft of the power tool and a tool holder adapted to support a working tool for oscillating rotational motion, the drive shaft having an axis of rotation, the oscillating mechanism comprising:
an elongated link mounted at one end thereof on said eccentric drive shaft for eccentric movement upon rotation of said drive shaft about said axis of rotation and including on an opposite end thereof a roller bearing having a loose fit with a small amount of play between an inner race and rollers of the bearing, and/or between the rollers and an outer race of the bearing in a radial direction relative to said axis of rotation of said drive shaft; and
an elongated drive arm having;
a first end coupled to said roller bearing of said link in a manner to isolate relative rotation and translation between said link and said drive arm while still imparting an oscillatory motion in one direction to said drive arm; and
a second end engageable to the tool holder to transfer the oscillatory motion to oscillating rotational motion of said tool holder.

13. The oscillating mechanism of claim 12 , wherein:
said link includes an upper link mountable on the eccentric drive shaft and a lower link offset from said upper link, said lower link defining a cylindrical opening; and
said second end of said drive arm is a spherical end slidably disposed within said cylindrical opening to permit relative rotation and axial translation between said drive arm and said lower link.

14. The oscillating mechanism of claim 13 , wherein said lower link includes a cylindrical bushing defining said cylindrical opening.

15. The oscillating mechanism of claim 13 , wherein said lower link includes a roller bearing having a loose fit with a small amount of play between the inner race and the rollers of the bearing, and/or between the rollers and the outer race of the bearing.

16. The oscillating mechanism of claim 13 , wherein said upper link includes a bearing mountable on the eccentric drive shaft.

17. The oscillating mechanism of claim 13 , further comprising a counterweight mountable on said eccentric shaft opposite said lower link.

Assignees

• Bosch Gmbh Robert
• Bosch Tool Corp

Inventors

• Rubens Jeremy
• Moreno Terrazas Jaime

Classifications

• B27B19/008

  having a plurality of saw blades or saw blades having plural cutting zones · CPC title

• B26B7/00

  Hand knives with reciprocating motor-driven blades · CPC title

• B24B27/08

  being portable · CPC title

• A61B17/142

  with reciprocating saw blades, e.g. with cutting edges at the distal end of the saw blades · CPC title

• B24B47/12

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