A multi-voltage battery pack for use with tools of different operating voltages including a housing, a first string of battery cells arranged in electrical series and disposed inside the housing, the first string having a first positive voltage terminal and a first negative voltage terminal, a second string of battery cells arranged in electrical series and disposed inside the housing, the second string having a second positive voltage terminal and a second negative voltage terminal, and a power tool interface shaped and configured to interchangeably (1) mechanically and electrically couple with a first battery pack interface of a first power tool that is configured to operate at a first operating voltage, and (2) mechanically and electrically couple with a second battery pack interface of a second power tool that is configured to operate at a second operating voltage.

A multi-voltage battery pack for use with tools of different operating voltages including a housing, a first string of battery cells arranged in electrical series and disposed inside the housing, the first string having a first positive voltage terminal and a first negative voltage terminal, a second string of battery cells arranged in electrical series and disposed inside the housing, the second string having a second positive voltage terminal and a second negative voltage terminal, and a power tool interface shaped and configured to interchangeably (1) mechanically and electrically couple with a first battery pack interface of a first power tool that is configured to operate at a first operating voltage, and (2) mechanically and electrically couple with a second battery pack interface of a second power tool that is configured to operate at a second operating voltage.

A method and device for electrodynamic braking of a universal motor. The method comprises the steps of continuously ascertaining a rotational speed of the universal motor, temporarily, periodically short-circuiting an armature of the universal motor with a semiconductor switch, and regulating firing angles of the semiconductor switch with a regulating device. The regulating device regulates firing angles of the semiconductor switch such that the rotational speed of the universal motor is adapted with minimal deviation to a rotational speed of a target rotational speed profile.

A method and device for electrodynamic braking of a universal motor. The method comprises the steps of continuously ascertaining a rotational speed of the universal motor, temporarily, periodically short-circuiting an armature of the universal motor with a semiconductor switch, and regulating firing angles of the semiconductor switch with a regulating device. The regulating device regulates firing angles of the semiconductor switch such that the rotational speed of the universal motor is adapted with minimal deviation to a rotational speed of a target rotational speed profile.

A first battery pack that is switchable between a first configuration having a first rated output voltage that corresponds to a first power tool rated operating voltage such that the first battery pack enables operation of the first power tool, and a second configuration having a second rated output voltage that corresponds to a second power tool rated operating voltage such that the first battery pack enables operation of the second power tool.

A first battery pack that is switchable between a first configuration having a first rated output voltage that corresponds to a first power tool rated operating voltage such that the first battery pack enables operation of the first power tool, and a second configuration having a second rated output voltage that corresponds to a second power tool rated operating voltage such that the first battery pack enables operation of the second power tool.

The present disclosure is directed to a convertible battery pack having an improved switching circuit. The switching circuit includes a converter element having a plurality of contacts positioned in the converter element such that as the converter element slides within the battery pack the contacts move from a first position to engage a first set of contact pads to a second position to engage a second set of contact pads. The converter element includes a pair of springs for each of the plurality of contacts that force the contacts into engagement with the contact pads but also allow the contacts to adjust for imperfections in the contact pad surface or the manufacturing tolerances of the contact pads or a support board that holds the contact pads.

The present disclosure is directed to a convertible battery pack having an improved switching circuit. The switching circuit includes a converter element having a plurality of contacts positioned in the converter element such that as the converter element slides within the battery pack the contacts move from a first position to engage a first set of contact pads to a second position to engage a second set of contact pads. The converter element includes a pair of springs for each of the plurality of contacts that force the contacts into engagement with the contact pads but also allow the contacts to adjust for imperfections in the contact pad surface or the manufacturing tolerances of the contact pads or a support board that holds the contact pads.

A power tool system including a multi-voltage battery pack for use with a first power tool, wherein the first power tool comprises a first battery pack interface and is configured to operate at a first operating voltage and a second power tool configured for use with the multi-voltage battery pack such that the system includes both the multi-voltage battery pack and the second power tool, wherein the second power tool comprises a second battery pack interface and is configured to operate at a second operating voltage, wherein the second operating voltage is higher than the first operating voltage.

A power tool system including a multi-voltage battery pack for use with a first power tool, wherein the first power tool comprises a first battery pack interface and is configured to operate at a first operating voltage and a second power tool configured for use with the multi-voltage battery pack such that the system includes both the multi-voltage battery pack and the second power tool, wherein the second power tool comprises a second battery pack interface and is configured to operate at a second operating voltage, wherein the second operating voltage is higher than the first operating voltage.