Abstract: A battery charger system includes multiple power channels to accommodate multiple battery chargers through a power input port. Each power channel includes a power outlet electrically coupled to the power input port through a relay. Each power channel further includes a current sensor. A controller is configured to estimate current in each of the power channels using the sensor signals, and configured to control the relays. The battery charger system is configured to provide power to the outlets by closing the corresponding relays, until the total current estimate is more than a maximum current limit, at which point the controller is configured to open the most recently closed relay. The controller is further configured to sequentially close remaining relays after the total current drops sufficiently, while maintaining the total current below the maximum current limit.

Abstract: A multi-socket power extension source includes a power inlet port, and power outlets coupled to the power inlet port through switches. The multi-socket power extension source includes a controller configured to control the switches. The controller is configured to repetitively determine if an estimate of a total current through the power inlet port exceeds a prescribed current limit. When the estimated total current exceeds the prescribed current limit, the controller is configured to identify the outlet having the largest current increase and turn off the switch coupled to that outlet. The controller is further configured to reconnect the surge outlet, when an updated estimated total current is less than the prescribed current limit by at least the current of the surge outlet, or after a prescribed reconnect time period. The multi-socket power extension source may be coupled to a secondary multi-socket power extension source in an expansion configuration.

Abstract: A battery charger system includes multiple power channels to accommodate multiple battery chargers through a power input port. Each power channel includes a power outlet electrically coupled to the power input port through a relay. Each power channel further includes a current sensor. A controller is configured to estimate current in each of the power channels using the sensor signals, and configured to control the relays. The battery charger system is configured to provide power to the outlets by closing the corresponding relays, until the total current estimate is more than a maximum current limit, at which point the controller is configured to open the most recently closed relay. The controller is further configured to sequentially close remaining relays after the total current drops sufficiently, while maintaining the total current below the maximum current limit.

Abstract: A method of refurbishing a handheld landscape power tool includes separating an original motor of the power tool from a tool head of the power tool. The tool head includes a tool shaft extending proximate to the original motor. A replacement power head and a shaft coupler are provided. The replacement power head includes a motor and a power shaft mechanically coupled to the motor. The shaft coupler includes a power shaft connecter coupled to a shaft-specific connecter. The replacement power head is coupled to the shaft coupler by connecting the power shaft connecter to the power shaft of the replacement power head. The tool head is coupled to the shaft coupler by connecting the shaft-specific connecter to the tool shaft of the tool head.

Abstract: An electric vehicle charging master controller includes an instruction processing unit, a user interface module, and a charging interface module. Electric vehicle (EV) charging equipment is external to the controller. The instruction processing unit is configured to execute instructions for charging electric vehicles (EVs). The charging interface module is configured to receive information from the instruction processing unit and transmit information to the EV charging equipment. The instruction processing unit is configured to transmit information to the charging interface module, which is designed to cause the EV charging equipment to direct charging current to the plurality of EVs, one at a time. The instruction processing unit is also configured to transmit information to the charging interface module designed to cause the EV charging equipment to stop the charging current to each EV when a charging cessation criterion has been met.

Abstract: A method of refurbishing a handheld landscape power tool includes separating an original motor of the power tool from a tool head of the power tool. The tool head includes a tool shaft extending proximate to the original motor. A replacement power head and a shaft coupler are provided. The replacement power head includes a motor and a power shaft mechanically coupled to the motor. The shaft coupler includes a power shaft connecter coupled to a shaft-specific connecter. The replacement power head is coupled to the shaft coupler by connecting the power shaft connecter to the power shaft of the replacement power head. The tool head is coupled to the shaft coupler by connecting the shaft-specific connecter to the tool shaft of the tool head.

Abstract: A power tool ensemble includes at least a power head, a first shaft coupler, and a second shaft coupler, for use with tool heads of landscaping tools. The power head includes a motor and a power shaft mechanically coupled to the motor. Each shaft coupler includes a power shaft connecter for connecting to the power shaft, and a shaft-specific connecter for connecting to tool shafts of the tool heads. In each shaft coupler, the power shaft connecter is mechanically coupled to the shaft-specific connecter. The shaft-specific connecter in the first shaft coupler has a different tool shaft configuration from the shaft-specific connecter in the second shaft coupler.

Abstract: A battery charger system includes multiple power channels to accommodate multiple battery chargers through a power input port. Each power channel includes a power outlet electrically coupled to the power input port through a relay. Each power channel further includes a current sensor. A controller is configured to estimate current in each of the power channels using the sensor signals, and configured to control the relays. The battery charger system is configured to provide power to the outlets by closing the corresponding relays, until the total current estimate is more than a maximum current limit, at which point the controller is configured to open the most recently closed relay. The controller is further configured to sequentially close remaining relays after the total current drops sufficiently, while maintaining the total current below the maximum current limit.

Abstract: A power tool ensemble includes at least a power head, a first shaft coupler, and a second shaft coupler, for use with tool heads of landscaping tools. The power head includes a motor and a power shaft mechanically coupled to the motor. Each shaft coupler includes a power shaft connecter for connecting to the power shaft, and a shaft-specific connecter for connecting to tool shafts of the tool heads. In each shaft coupler, the power shaft connecter is mechanically coupled to the shaft-specific connecter. The shaft-specific connecter in the first shaft coupler has a different tool shaft configuration from the shaft-specific connecter in the second shaft coupler.

Abstract: A method of refurbishing a handheld landscape power tool includes separating an original motor of the power tool from a tool head of the power tool. The tool head includes a tool shaft extending proximate to the original motor. A replacement power head and a shaft coupler are provided. The replacement power head includes a motor and a power shaft mechanically coupled to the motor. The shaft coupler includes a power shaft connecter coupled to a shaft-specific connecter. The replacement power head is coupled to the shaft coupler by connecting the power shaft connecter to the power shaft of the replacement power head. The tool head is coupled to the shaft coupler by connecting the shaft-specific connecter to the tool shaft of the tool head.