Electrical contact arrangement for disengageable parts of an electric tool

Claim 1

An electric tool for use in a drilling or chiselling operation including a tool housing, a handle detachably connected to said tool housing, said tool housing comprising a first housing part having a tool holder at one end arranged to receive the tool and extending in the axial direction of said tool holder, and a second housing part connected to said first housing part at its end opposite said holder and extending transversely of and laterally outwardly from said first housing part, said handle extending transversely of the axial direction of said tool holder and connected to the opposite end of said first housing part from said tool holdeR and to said second housing part, electrical means for operating the electric tool comprising first electrical parts located in said second housing part and second electrical parts located in said handle and said first electrical parts and second electrical parts being connectible for operating the electric tool, wherein the improvement comprises that said first electrical parts and second electrical parts each comprises contact elements arranged to interfit with one another with said contacts comprising knife blade-shaped contacts secured to one of said first and second electrical parts and stirrup-shaped contacts secured to the other one of said first and second electrical parts, said knifeblade shaped contacts and said stirrup-shaped contacts are displaceably interengageable to provide electrical contact between said first electrical parts and said second electrical parts, displaceable means for mechanically interconnecting said tool housing and said handle so that said handle can be removed with said second electrical parts and said contacts secured thereto as a unit from said tool housing, at least one first guide element provided on said second housing part laterally adjacent said contacts therein and at least one second guide element provided on said handle laterally adjacent said contacts therein and said first and second guide elements being arranged to interengage when said tool housing and handle are assembled together for guiding said knife-blade shaped and stirrup-shaped contacts into interengagement and said contacts being arranged to disengage from one another automatically when said handle is removed from said tool housing, said second housing part including a removable cover, said first electrical parts within said second housing part comprising a stator including a casing with said stator and casing removably mounted as a unit in said second housing part, said contacts secured within said second housing part being connected to said casing of said stator, said stator said casing and said contacts connected thereto being removable from said second housing part as a unit in a direction transversely of the plugging direction of said handle into said second housing part, and said knifeblade shaped contacts arranged with the knife edges thereof located in planes extending substantially parallel to the direction of the removal of said stator said casing and said contacts from said second housing part and parallel to the plugging direction of said handle in said second housing part so that upon removal of said stator casing said contacts on said stator casing are automatically disconnected from said contacts secured within said handle.