Adjustable guard construction for cut-off machine

• US 4,060,940 A
• Filed: 01/13/1976
• Issued: 12/06/1977
• Est. Priority Date: 01/13/1976
• Status: Expired due to Term

• Current Assignee: Black Pearl Manufacturing Incorporated
• Original Assignee: Black Pearl Manufacturing Incorporated
• Inventors: DeWitt, deceased, Erik John
• Primary Examiner(s): Jones, Jr., James L.
• Application Number:
  US05/648,759
• Time in Patent Office: 693 Days
• Field of Search: 51/170 PT, 51/170 T, 51/268, 51/271, 51/272, 51/273, 30/388, 30/390, 30/500
• US Class Current: 451/358
• CPC Class Codes: B24B 55/05 specially designed for portable grinding machines
• CPC Class Codes: B25F 5/026 in the form of an auxiliary handle B25F5/024 takes precedence

Abstract

A portable, electric cut-off machine including an electric motor powered abrasive disc. Front and rear handles are provided for convenient two-hand operation of the tool and are electrically isolated for operator protection. A protective guard encompasses substantially 210° of the abrasive disc and is adjustably mounted in novel fashion on the housing and one of the handles. A supporting shoe is adjustably attached to the guard. The tool is constructed so that parts may be reversed for either right-handed or left-handed operators.

Claims

1. A circular cut-off machine comprising a housing having an electric motor therein, transmission means interconnecting said electric motor and an output spindle, an abrasive disc fixed to said output spindle, handle means for said tool including a first handle positioned rearwardly of said housing and a second handle connected to said housing so as to be positioned at the forward end portion thereof and adjacent said abrasive disc, a protective guard for said abrasive disc including a guard encompassing a portion of said disc, said guard being supported upon said housing adjacent said output spindle and adjustable about the axis of said spindle, and means associated with said second handle and releasably secured to said guard at a position radially spaced from said spindle axis for rigidly securing said guard in its adjusted position to said housing through said second handle.

2. A circular cut-off machine comprising a housing having an electric motor therein, transmission means interconnecting said electric motor and an output spindle, an abrasive disc fixed to said output spindle, handle means for said tool including a first handle positioned rearwardly of said housing and a second handle positioned forwardly of said housing adjacent said abrasive disc, a protective guard for said abrasive disc including a guard encompassing a portion of said disc, said guard being supported upon said housing adjacent said output spindle and adjustable about the axis of said spindle, a bracket fixed to said second handle, means releasably securing said bracket to said housing and to said guard at a position radially spaced from said spindle axis, whereby to rigidly secure said guard in its adjusted position.

3. A circular cut-off machine comprising a housing having an electric motor therein, transmission means interconnecting said electric motor and an output spindle, an abrasive disc fixed to said output spindle, handle means for said tool including a first handle positioned rearwardly of said housing and a second metal handle positioned forwardly of said housing adjacent said abrasive disc, a protective guard for said abrasive disc including a guard encompassing a portion of said disc, said guard being supported upon said housing adjacent said output spindle and adjustable about the axis of said spindle, a metal bracket fixed to said second handle, means releasably securing said bracket to said housing and to said guard at a position radially spaced from said spindle axis, said releasable securing means including electrical insulating means isolating said second handle and bracket from said housing and said guard, whereby to rigidly secure said guard in its adjusted position.

4. A circular cut-off machine comprising a housing having an electric motor therein, transmission means interconnecting said electric motor and an output spindle, an abrasive disc fixed to said output spindle, a handle connected to said housing so as to be positioned adjacent said abrasive disc, a protective guard for said abrasive disc including a guard encompassing a portion of said disc, said guard being supported upon said housing adjacent said output spindle and adjustable about the axis of said spindle, and means including electrical insulation means associated with said handle and releasably secured to said guard at a position radially spaced from said spindle axis for electrically isolating said handle from said guard and for rigidly securing said guard in its adjusted position.

5. A circular cut-off machine comprising a housing having an electric motor therein, transmission means interconnecting said electric motor and an output spindle, an abrasive disc fixed to said output spindle, a handle connected to said housing and positioned adjacent said abrasive disc, a protective guard for said abrasive disc including a guard encompassing a portion of said disc, said guard being supported upon and frictionally attached to said housing adjacent said output spindle, said guard being manually movable to overcome said frictional attachment to thereby adjust said guard about the axis of said spindle, and means associated with said handle and releasably secured to said guard at a position radially spaced from said spindle axis for rigidly securing said guard in its adjusted position.

6. A circular cut-off machine comprising a housing having an electric motor therein, transmission means interconnecting said electric motor and an output spindle, an abrasive disc fixed to said output spindle, handle means for said tool including a first handle connected to said housing so as to be positioned rearwardly thereof and a second handle connected to said housing adjacent said abrasive disc, a protective guard for said abrasive disc including a guard encompassing a portion of said disc, said guard being supported upon said housing adjacent said output spindle and adjustable about the axis of said spindle, and means associated with said second handle and releasably secured to said guard at a position radially spaced from said spindle axis for rigidly securing said guard in its adjusted position, said second handle, said abrasive disc, and said guard being readily repositionable relative to said housing.

7. A circular cut-off machine comprising a housing including a motor housing and gear case, an electric motor in said motor housing and having an output shaft, a gear train in said gear case and driven by said output shaft, a spindle driven by said gear train and having an abrasive disc fixed thereto, a cylindrical hub on said gear case surrounding said spindle, a guard encompassing the upper portion of said disc and frictionally clamped to said hub for adjustment about the axis of said spindle, a first handle fixed to said motor housing, a second handle supported upon said gear case, means releasably connecting said second handle to said guard at a point spaced from said hub for rigidly securing said guard in its adjusted position, said guard being adjustable about said hub by releasing only said releasable connecting means and manually overcoming said frictional clamping force.

8. A circular cut-off machine comprising a housing including a motor housing and gear case, an electric motor in said motor housing and having an output shaft, a gear train in said gear case and driven by said output shaft, a spindle driven by said gear train and having an abrasive disc fixed thereto, a guard encompassing the upper portion of said disc and supported on said housing for adjustment about the axis of said spindle, a first handle fixed to said motor housing, a second handle constructed of metal supported through a bracket upon said gear case, means releasably connecting said bracket to said guard at a point spaced from said spindle, whereby to rigidly secure said guard in its adjusted position;

said second handle being electrically insulated from said housing and said guard.

9. A circular cut-off machine comprising a housing including a motor housing and gear case, an electric motor in said motor housing and having an output shaft, a gear train in said gear case and driven by said output shaft, a spindle driven by said gear train and having an abrasive disc fixed thereto, a guard encompassing the upper portion of said disc and supported on said housing for adjustment about the axis of said spindle, a first handle fixed to said motor housing, a second handle constructed of metal supported through a metal bracket upon said gear case, means releasably connecting said bracket to said guard at a point spaced from said spindle, whereby to rigidly secure said guard in its adjusted position;

electrical insulators permanently fixed to said bracket and electrically insulating said bracket and said second handle from said gear case and said guard.