Restart protection device

A battery-operated electric power tool, comprising:

• a battery pack;
• a battery pack interface configured to receive the battery pack;
• and
• a restart protection device, wherein the restart protection device comprises:
• a control capacitor having a cathode and an anode, wherein the cathode is connected to a ground connection of the battery-operated electric power tool, and wherein the anode is connected, via the battery pack interface, to a connection line of the battery pack of the battery-operated electric power tool;
• a controllable discharge circuit for discharging the control capacitor, wherein a control input of the controllable discharge circuit is directly connected to a signal line of the battery pack via the battery-pack interface to detect presence or absence of the battery pack, wherein the control input is a gate terminal of a MOSFET and the signal line is a temperature control line or a data interface;
• a measuring element for detecting a charge state of the control capacitor;
• and
• a controller connected to the measuring element, wherein the controller is configured to block a starting of the electric power tool when an operating switch of the electric power tool is actuated, and at the same time, the charge state of the control capacitor detected by the measuring element is below a defined threshold value.

A restart protection method for a battery-operated electric power tool, the method comprising:

• inserting a battery pack into the battery-operated electric power tool;
• charging a control capacitor based at least in part on the inserting;
• detecting a charge state of the control capacitor;
• blocking a starting of the battery-operated electric power tool when an operating switch of the battery-operated electric power tool is actuated, wherein the blocking is based at least in part on detecting the charge state of the control capacitor is below a defined threshold value;
• monitoring, using a controllable discharge circuit, a signal line of the battery pack, wherein a control input of the controllable discharge circuit is directly connected to the signal line via a battery-pack interface to detect presence or absence of the battery pack, wherein the control input is a gate terminal of a MOSFET and the signal line is a temperature control line or a data interface;
• detecting a removal of the battery pack from the battery-operated electric power tool based at least in part on the monitoring;
• and
• discharging, using the controllable discharge circuit, the control capacitor, wherein the discharging is based on detecting the removal of the battery pack from the battery-operated electric power tool.