System and method for remote sensing and receiving

• US 5,728,933 A
• Filed: 09/20/1995
• Issued: 03/17/1998
• Est. Priority Date: 12/20/1989
• Status: Expired due to Term

• Current Assignee: Sentech Incorporated (General Dynamics Corporation)
• Original Assignee: Sentech Incorporated (General Dynamics Corporation)
• Inventors: Campbell, Alan J., Schultz, Thomas J.
• Primary Examiner(s): Chilcot, Richard
• Assistant Examiner(s): Oen, William L.
• Application Number:
  US08/530,938
• Time in Patent Office: 909 Days
• Field of Search: 73/146.5, 73/146.8, 73/118.1, 73/178 R, 340/440, 340/445, 364/550, 364/558, 364/565
• US Class Current: 73/146.5
• CPC Class Codes: A62C 37/50 Testing or indicating devices for determining the state of readiness of the equipment
• CPC Class Codes: B60C 23/009 having wheels on a trailer
• CPC Class Codes: B60C 23/0408 transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
• CPC Class Codes: B60C 23/0423 Photo-electric, infrared or visible light means
• CPC Class Codes: B60C 23/0479 Communicating with external units being not part of the vehicle, e.g. tools for diagnostic, mobile phones, electronic keys or service stations
• CPC Class Codes: B60C 23/0496 Valve stem attachments positioned outside of the tyre chamber
• CPC Class Codes: G01L 19/086 for remote indication

Abstract

A sensing and displaying system is provided including a sensor unit having a transducer disposed in intimate contact with a vessel. The transducer senses a characteristic within the vessel like pressure and outputs electrical signal representative thereof. The sensor unit further includes a response signal generator which transmit a signal representative of the characteristic. A receiver unit receives the transmitted signal and converts it to visual indicia of the characteristic, for example, a number on a liquid crystal display. The system is capable of two-way communication between the sensor unit and the receiver unit. Both the sensor unit and receiver unit store transmitted data in internal memory.

Claims

1. A sensor and display system comprising:

a sensor unit having a first input coupled to a vessel and having a second input receptive to a command signal, for remotely receiving the command signal and, in response to receiving the command signal, sensing a parameter of the vessel and generating a response signal indicative of the parameter; and

a handheld display unit having an input in remote communication with the sensor unit and being operable for remotely transmitting the command signal to the sensor unit and for remotely receiving the response signal from the sensor unit, to display information relating to the parameter.

2. The system of claim 1, wherein the vessel is a tire and the parameter is air pressure.

3. The system of claim 2 for operation with a tire having a valve, wherein the sensor unit includes a cap disposed to attach to the valve of the tire for sensing pressure therein.

4. A system for sensing a parameter of a vessel in a first location and displaying information relating to the parameter in a second location, the system comprising:

at least one sensor unit including;

a transducer having an input coupled to the vessel for sensing a parameter of the vessel and having an output indicating the parameter;

a signal converter having an input coupled to the transducer output, for conditioning the transducer output for transmission;

a transmitter circuit having an input coupled to the signal converter for producing an output indicative of the parameter;

a power circuit having an input receptive to a command signal and having an output coupled to the transducer and the signal converter and the transmitter circuit, for remotely receiving the command signal and, in response to receiving the command signal, providing power to the transducer and the signal converter and the transmitter circuit; and

a handheld display unit including;

a processor circuit having an input in remote communication with the sensor unit and being operable for remotely transmitting the command signal to the sensor unit, remotely receiving the transmitter circuit output, and conditioning the transmitter circuit output for display; and

a display having an input coupled to the processor circuit, for receiving the conditioned transmitter circuit output and displaying information relating to the parameter.

5. The system of claim 4, wherein the signal converter comprises a voltage-to-frequency converter and the transmitter circuit output has a frequency indicative of the parameter.

6. The system of claim 4, wherein the transmitter circuit comprises an LED driver circuit and at least one LED operated by the LED driver circuit.

7. The system of claim 4, wherein the transmitter circuit output is an infrared signal indicative of the parameter.

8. The system of claim 4, wherein the processor circuit comprises:

a switch manually actuated between an open state and a closed state;

an amplifier circuit in remote communication with the sensor unit, for remotely receiving the transmitter circuit output and for conditioning the transmitter circuit output for display;

a processor coupled to the switch for generating a command reference signal in response to the switch being in the closed state and coupled to the amplifier circuit for further conditioning the transmitter circuit output for display; and

a command generator circuit coupled to the processor and in remote communication with the sensor unit, for receiving the command reference signal, generating the command signal from the command reference signal, and remotely transmitting the command signal.

9. The apparatus of claim 8, wherein the display unit further comprises a battery circuit coupled to the switch for providing power to the display unit in response to the switch being in the closed state.

10. A sensor and display system for executing one of a plurality of functions indicated by one of a plurality of control signals including a first read signal, a second read signal, and a write signal, the system comprising:

a sensor unit having a first input receptive to a control signal and receptive to first data in response to the write signal, a second input coupled to a vessel, and a memory device coupled to the first input, for remotely receiving the control signal, remotely receiving the first data in response to the write signal, storing the first data in response to the write signal, and generating a response signal indicative of a parameter of a vessel in response to the first read signal and indicative of second data in response to the second read signal; and

a display unit having an input in remote communication with the sensor unit and a display coupled to the input and being operable for remotely transmitting the control signal to the sensor unit, to remotely receive the response signal from the sensor unit and display information conveyed by the response signal.

11. The apparatus of claim 10, wherein the display unit further comprises a storage device coupled to the input for storing the information conveyed by the response signal.

12. The system of claim 10, wherein the sensor unit comprises:

a detector circuit in remote communication with the display unit for remotely receiving the control signal from the display unit and, in response to the write signal, remotely receiving the first data from the display unit;

a parameter measurement circuit coupled to the vessel and the detector circuit, for sensing the parameter in response to the detector circuit receiving the first read signal;

a processor circuit coupled to the parameter measurement circuit and coupled to the detector circuit and having;

the memory device coupled to the detector circuit, the processor circuit reading the second data from the memory device in response to the second read signal and storing the first data in the memory device in response to the write signal; and

an output indicating the parameter in response to the first read signal and indicating the second data in response to the second read signal; and

an output circuit coupled to the processor circuit and in remote communication with the display unit, for generating the response signal from the processor circuit output and for remotely transmitting the response signal to the handheld display unit.

13. The sensor unit of claim 12 further comprising:

an activation circuit coupled to the detector circuit, the parameter measurement circuit, the processor circuit and the output circuit, for providing power to the detector circuit and, in response to the detector circuit receiving the control signal, providing power to the parameter measurement circuit, the processor circuit and the output circuit to perform functions indicated by the control signal.

14. The system of claim 10, wherein the display unit comprises:

a receiver circuit in remote communication with the sensor unit, for remotely receiving the response signal and conditioning the response signal for display;

a computer circuit coupled to the receiver circuit and having the display, for displaying the information conveyed by the response signal and for generating the control signal; and

a transmitter circuit coupled to the computer circuit and in remote communication with the sensor unit, for transmitting the control signal.

15. The system of claim 14, wherein the display unit further comprises a power circuit coupled to the receiver circuit, the computer circuit and the transmitter circuit and including a switch manually actuated between an open state and a closed state, for providing power to the receiver circuit, the computer circuit and the transmitter circuit in response to the switch being in the closed state.

16. The system of claim 10, wherein the parameter is pressure and wherein the display unit further comprises a barometric pressure sensor coupled to the display, for displaying a pressure value derived from a barometric pressure and the response signal in response to the first read signal.

17. The system of claim 10, wherein the vessel is a fire extinguisher and the parameter is pressure.

18. A handheld display unit for operation with a remote sensor unit, the display unit comprising:

a processor circuit having an input in remote communication with the sensor unit and being operable for remotely activating the sensor unit, to remotely receive a response signal from the sensor unit and condition the response signal for display; and

a display having an input coupled to the processor circuit, for receiving the conditioned response signal and displaying information conveyed by the response signal.

19. The display unit of claim 18, wherein the processor circuit comprises:

a switch manually actuated between an open state and a closed state;

an amplifier circuit in remote communication with the sensor unit, for remotely receiving the response signal and conditioning the response signal for display;

a processor coupled to the switch for generating a command reference signal in response to the switch being in the closed state and coupled to the amplifier circuit for further conditioning the response signal for display;

a command generator coupled to the processor circuit and in remote communication with the sensor unit, for generating a command signal from the command reference signal and remotely transmitting the command signal to activate the sensor unit.

20. The display unit of claim 19 further comprising a battery circuit coupled to the switch for providing power to the display unit in response to the switch being in the closed state.

21. A user controlled, handheld display unit for operation with a sensor unit comprising:

a transmitter circuit in remote communication with the sensor unit for remotely transmitting a control signal to the sensor unit, the control signal indicating a request for the sensor unit;

a receiver circuit in remote communication with the sensor unit, for remotely receiving a response signal from the sensor unit and conditioning the response signal for display; and

a computer circuit having a data entering device coupled to the transmitter circuit and having a display coupled to the receiver circuit, for generating the control signal in response to an indication from the user and for displaying information conveyed by the response signal.

22. The apparatus of claim 21, wherein the display unit further comprises a power circuit coupled to the receiver circuit, the computer circuit, and the transmitter circuit and including a switch manually actuated by the user between an open state and a closed state, for providing power to the receiver circuit, the computer circuit, and the transmitter circuit in response to the switch being in the closed state.

23. A sensor unit in remote communication with a handheld display unit, the sensor unit comprising:

a transducer having an input coupled to a vessel for sensing a parameter of the vessel and having an output indicating the parameter;

a signal converter having an input coupled to the transducer output, for conditioning the transducer output for transmission;

a transmitter circuit having an input coupled to the signal converter for producing the output indicative of the parameter; and

a power circuit having an input receptive to a command signal from the display unit, a battery coupled to the input, and an output coupled to the transducer and the signal converter and the transmitter circuit, for remotely receiving the command signal and, in response to remotely receiving the command signal, the battery providing power to the transducer, the signal converter and the transmitter circuit.

24. The sensor unit of claim 23, wherein the signal converter comprises a voltage-to-frequency converter and the transmitter circuit output has a frequency indicative of the parameter.

25. A sensor unit for operation with a remote display unit, wherein the sensor unit receives one of a plurality of control signals from the display unit, the plurality of control signals including a write signal, a first read signal and a second read signal, the sensor unit comprising:

a detector circuit in remote communication with the display unit for remotely receiving a control signal from the display unit and, in response to receiving the write signal, remotely receiving first data from the display unit;

a parameter measurement circuit coupled to a vessel and the detector circuit, for sensing a parameter of the vessel in response to the detector circuit receiving the first read signal;

a processor circuit coupled to the parameter measurement circuit and coupled to the detector circuit and having;

a memory device coupled to the detector circuit, the processor circuit reading second data from the memory device in response to the second read signal and storing the first data in the memory device in response to the write signal;

an output indicating the second data in response to the second read signal and indicating the parameter in response to the first read signal;

an output circuit coupled to the processor circuit and in remote communication with the display unit, for generating a response signal from the processor circuit output and for remotely transmitting the response signal to the display unit.

26. The sensor unit of claim 25 further comprising:

an activation circuit coupled to the detector circuit, the parameter measurement circuit, the processor circuit and the output circuit, for providing power to the detector circuit and, in response to the detector circuit receiving the control signal, providing power to the parameter measurement circuit, the processor circuit and the output circuit to perform functions indicated by the control signal.

27. A method of receiving and displaying information in a user controlled, handheld display unit, wherein the information is conveyed in a signal transmitted from a sensor unit physically separate from the display unit, the method comprising the steps of:

receiving an indication from the user to activate the sensor unit;

in response to receiving the indication from the user, remotely activating the sensor unit;

remotely receiving the signal from the .activated sensor unit;

conditioning the signal for display; and

displaying information conveyed in the signal.

28. A method of performing functions indicated by one of a plurality of control signals, including a first read signal, a second read signal and a write signal, in a system comprising a sensor unit and a display unit, wherein a control signal is remotely transmitted from the display unit to the sensor unit, the method comprising the steps of:

remotely receiving the control signal from the display unit;

remotely receiving first data from the display unit in response to the write signal;

storing the first data in response to the write signal;

sensing a parameter of a vessel in response to the first read signal;

in response to sensing the parameter, remotely transmitting a first response signal indicative of the parameter to the display unit;

reading second data in response to the second read signal; and

in response to reading the second data, remotely transmitting a second response signal indicative of the second data to the display unit.

29. A method for communicating between a sensor and a receiver in a remote detect and display system using a carrier wave, the sensor being spatially separate from the receiver, said method comprising the steps of:

sending an activation signal having at least one pulse of the carrier wave from the receiver to the sensor;

sending first pulses of the carrier wave to the sensor for initiating transmission of first data by the sensor;

receiving a first signal from the sensor indicative of the first data;

sending the carrier wave to the sensor for enabling the sensor to read second data;

sending the activation signal from the receiver to the sensor;

sending second pulses of the carrier wave to the sensor for initiating transmission of the second data; and

receiving a second signal from the sensor indicative of the second data.

30. A method for communicating between a sensor and a receiver in a remote detect and display system using a carrier wave and an activation signal having at least one pulse of the carrier wave, the sensor being spatially separate from the receiver, said method comprising the steps of:

enabling the sensor for reception of first data by sending combinations of the activation signal and the carrier wave;

sending the first data to the sensor by transmitting the activation signal followed by a first data signal indicative of the first data;

receiving a second data signal indicative of the first data signal from the sensor;

determining whether the second data signal is indicative of the first data; and

in response to the second data signal not being indicative of the first data, sending the first data to the sensor unit.