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

• US 20060195202A1
• Filed: 02/08/2006
• Published: 08/31/2006
• Est. Priority Date: 07/18/2002
• Status: Active Grant

• Current Assignee: Brian R. Crowell, Daniele C. Brotto
• Original Assignee: Brian R. Crowell, Daniele C. Brotto
• Inventors: Brotto, Daniele C., Crowell, Brian R.
• Granted Patent: US 7,346,406 B2
• Time in Patent Office: Days
• US Class Current: 700/83
• CPC Class Codes: B23D 59/008 comprising computers
• CPC Class Codes: B25B 23/14 Arrangement of torque limiters or torque indicators in wrenches or screwdrivers couplings for transmitting rotation or clutches F16D; devices for measuring torque per se G01L
• CPC Class Codes: B25F 5/00 Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for
• CPC Class Codes: H04B 2203/542 using zero crossing information
• CPC Class Codes: H04B 2203/5445 Local network
• CPC Class Codes: H04B 2203/547 via DC power distribution
• CPC Class Codes: H04B 2203/5475 adapted for drill or well combined with data transmission
• CPC Class Codes: H04B 2203/5483 using coupling circuits
• CPC Class Codes: H04B 3/54 Systems for transmission via power distribution lines

Abstract

An apparatus and method for obtaining data stored in an electronic module within a power tool over a power line cord of the tool, and without any disassembly of the tool being required. An interface subsystem applies a high frequency, low power AC input signal to the power cord of the tool. A controller within the tool recognizes this signal as an indication that the tool is to be placed in a communications mode. The controller modulates a power switching device used for turning on and off the motor of the tool in such a fashion that current pulses are transmitted over the power line cord back to the interface subsystem. The current pulses correspond to tool usage/performance/identification information stored in the electronic module of the tool. This information is interpreted by a current reader circuit of the interface subsystem as binary information which is then transmitted to an external computing device for analysis and/or recording.

Claims

1. A power tool comprising:

a power cord;

a controller housed within said power tool operable to recognize an input signal received over said power cord, and to enter a communications mode in response to receiving 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 receipt of said input signal, and to transmit signals over said power cord representative of said stored operational information.

2. The power tool of claim 1, wherein said input signal comprises an AC input signal, said controller entering a communications mode upon receipt of said AC input signal.

3. The power tool of claim 2, wherein said controller generates current pulses that are transmitted over said power cord, in response to receiving said AC input signal, and wherein said current pulses represent said stored operational information.

4. The power tool of claim 1, wherein said signals transmitted over said power cord are synchronized with said input signal.

5. The power tool of claim 1, wherein said signals transmitted over said power cord comprise periodic pulses.

6. A system for communicating information between a power tool and an independent subsystem using a power cord of the tool as a signal conducting medium, the system comprising:

an independent interface subsystem adapted to be coupled to said power cord;

a controller housed within said tool operable to recognize an input signal 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 power cord to said independent interface subsystem that correspond to said stored operational information.

7. The system of claim 6, wherein said independent interface subsystem sends said input signal to said power tool over said power cord.

8. The system of claim 7, wherein said signals transmitted over said power cord to said independent interface subsystem are synchronized with said input signal.

9. The system of claim 6, wherein said signals sent over said power cord to said independent interface subsystem comprise periodic pulses.

10. The system of claim 9, wherein said periodic pulses comprise current pulses.

11. The system of claim 7, wherein said input signal comprises an AC input signal having a frequency above about 60 Hz.

12. The system of claim 11, wherein said AC signal comprises a frequency of about 300 Hz.

13. A system for communicating stored performance related information for an electrically powered device, in which the electrically powered device has a motor that is activated by an electronic switching element housed with said device, the system comprising:

a controller housed within said device;

a memory housed within said device and in communication with said controller, the memory operating to store operational information for said device;

an interface subsystem adapted to be coupled to a power cord of said device and to cause stored operational information in said memory to be transmitted, as electrical signals formed by actuating said switching element, that correspond to said stored operational information, over said power cord back to said interface subsystem.

14. The system of claim 13, wherein said interface subsystem further operates to decode said electrical signals received via said power cord.

15. The system of claim 13, wherein said interface subsystem further operates to send an input signal over said power cord to inform said controller that said stored operational information is to be transmitted back to said interface subsystem.

16. The system of claim 15, wherein said input signal comprises an AC signal having a frequency greater than about 60 Hz.

17. The system of claim 16, wherein said AC input signal has a frequency of about 300 Hz.

18. The system of claim 13, wherein said electrical signals represent electrical pulses.

19. The system of claim 18, wherein said electrical pulses comprise current pulses.

20. The system of claim 16, wherein said electrical signals are capacitively coupled onto said AC signal being supplied over said power cord to said device.

21. The system of claim 13, wherein said device comprises a power tool.

22. The system of claim 13, wherein said device comprises a hand held power tool.

23. A method for communicating operational information for an electrically powered device, from the device to an independent subsystem via a power cord of the device, the method comprising:

storing operational information concerning the device in a memory component housed within the device;

using a 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 power cord.

24. The method of claim 23, further comprising coupling an independent interface device to said power cord to generate said electrical input signal over said power cord.

25. The method of claim 23, further comprising synchronizing the transmission of said representative electrical signals with a frequency of said electrical input signal.

26. The method of claim 23, further comprising using said independent interface device to decode said representative electrical signals.

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

a receptacle for electrically coupling with said power cord;

a circuit for generating an electrical input signal transmitted over said power cord to said device, said signal being 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 power cord; and

said circuit further operating to decode signals representative of operational information pertaining to said device, received over said power cord from said device.

28. The interface system of claim 27, wherein said electrical input signal comprises an AC signal having a frequency greater than about 60 hertz.

29. The interface system of claim 28, wherein said circuit comprises a circuit operable to decode current pulses coupled onto said AC signal, transmitted from said device to said circuit.

30. 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 signal received over an AC power cord 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 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 signal pulses over said power cord to an external device.