Shopping cart system

A method for handling shopping carts, comprising:

• supplying a charging current to each terminal device of a plurality of shopping carts each including a terminal device by a power supply device;
• receiving, at an input connector, from the power supply device or a previous stage shopping cart, a charging current of a battery of the terminal device and a DC voltage of a DC power supply included in the power supply device and different from a power supply that supplies the charging current;
• outputting, by a first output connector, to an input connector of another shopping cart connected to a subsequent stage of the shopping cart, the DC voltage via the first resistor and a part of the charging current received by the input connector;
• outputting, by a second output connector, to the input connector of the shopping cart, the charging current and a DC voltage via a second resistor connected in series to an output line of the DC power supply;
• measuring a current flowing through the second resistor;
• and
• stopping, by an energization controller, an output of the charging current when the current measured falls below a predetermined value.

A system for managing shopping carts, comprising:

• a plurality of shopping carts each including a terminal device;
• and
• a power supply device configured to supply a charging current to each of the terminal devices, wherein
• each of the plurality of shopping carts includes
• an input connector configured to receive, from the power supply device or a previous stage shopping cart, a charging current of a battery of the terminal device and a DC voltage of a DC power supply included in the power supply device and different from a power supply that supplies the charging current,
• a first resistor connected in series to an input line of the DC voltage, and
• a first output connector configured to output, to an input connector of another shopping cart connected to a subsequent stage of the shopping cart, the DC voltage via the first resistor and a part of the charging current received by the input connector, and
• the power supply device includes
• a second output connector configured to output, to the input connector of the shopping cart, the charging current and a DC voltage via a second resistor connected in series to an output line of the DC power supply,
• a current measurement component configured to measure a current flowing through the second resistor, and
• an energization controller configured to stop an output of the charging current when the current measured by the current measurement component falls below a predetermined value.