Patent ID: 9041322
Filing Date: 2015-05-26
Classification: B25F

Abstract:
1. An electric power tool, comprising a battery pack, and a tool body configured so that the battery pack is detachably attached to the tool body, wherein the tool body is configured to be joined to: any one of a plurality of types of battery packs having different rated output voltages; or a battery pack having a rated output voltage higher than a rated output voltage compliant to the tool body, of said plurality of types of battery packs, wherein a battery pack attached to the tool body is configured to supply electric power to the tool body side, wherein in each of said plurality of types of battery packs, one or more battery cells are connected in series or parallel and the number of battery cells connected in series is different from each other, thereby the packs having different rated output voltages, wherein said tool body comprises a housing having an attached part to which said battery pack is detachably attached, wherein said tool body is provided, in the housing, with: a motor as a drive source; a drive part configured to be driven with the motor; a switch as an operation input part connected to said battery pack through battery terminals; and a control circuit configured to perform a drive control of said motor in response to an operation of the switch, wherein said attached part of the tool body is configured to be joined to: a battery pack having a rated output voltage compliant to a characteristic of the motor in the tool body, of said plurality of types of battery packs; and also another battery pack having a first rated output voltage higher than the rated output voltage compliant to the characteristic of the motor in the tool body, of said plurality of types of battery packs, the battery pack joined to the attached part being configured to supply electric power to the tool body side through said battery terminals, wherein said attached part of the tool body is further configured to prohibit a battery pack, having a second rated output voltage higher than the rated output voltage compliant to the characteristic of the motor in the tool body by at least a predetermined voltage difference, from being joined to the attached part, the second rated output voltage being higher than the first rated output voltage.