System and method for data retrieval in AC power tools via an AC line cord

A system for communicating information between a power tool and an independent subsystem using an alternating current (AC) power cord of the tool as a signal conducting medium, the system comprising:

• an independent interface subsystem adapted to be coupled to a plug of said AC power cord;
• a controller housed within said tool operable to recognize an input signal transmitted over said AC power cord from said independent interface subsystem and to enter a communications mode in response to said input signal;
• a memory component housed within said tool and in communication with said controller, for storing operational information relating to said power tool;
• and
• said controller operating to obtain stored operational information from said memory upon detection of said input signal, and to transmit signals over said AC power cord to said independent interface subsystem that correspond to said stored operational information.

A method for communicating operational information for an alternating current (AC) powered device, from the device to an independent subsystem via an AC power cord of the device, the method comprising:

• storing operational information concerning the device in a memory component housed within the device;
• using said AC power cord of the device to transmit an electrical input signal to a controller housed within the device that stored operational information in said memory is to be transmitted from said device;
• and
• using the controller to access the memory and to transmit the stored operational information, as representative electrical signals, back over the AC power cord.

An interface system for communicating with an AC powered device, wherein the device has a memory for storing information relating to the device, and an AC power cord for receiving an AC power signal to power the device, the interface system comprising:

• a receptacle for electrically coupling with a plug of said AC power cord;
• a circuit for generating an electrical input signal transmitted over said AC power cord to said device, said electrical input signal being different from said AC power signal operable to place said device in a communications mode so that information stored in said memory of said device can be transmitted from said device over said AC power cord;
• and
• said circuit further operating to decode signals representative of operational information pertaining to said device, received over said AC power cord from said device.

A method of obtaining stored information relating to operational performance of an AC powered power tool, comprising:

• storing operational performance information relating to operation of said AC powered power tool in a memory housed within a housing of said power tool;
• using a controller housed within said housing of said power tool to monitor for a communications signal received over an AC power cord of said power tool, where said communications signal is different from an AC power signal used to power said power tool during normal operation of said power tool;
• when said signal is detected by said controller, causing said controller to obtain said stored information from said memory;
• using said controller to generate electrical signal pulses representative of said stored information by modulating a switch of said power tool that is used to turn on and off a motor of said power tool;
• and
• transmitting said electrical signal pulses over said AC power cord to an external device.