Remote monitoring system for instrumentation

• US 5,539,396 A
• Filed: 09/24/1993
• Issued: 07/23/1996
• Est. Priority Date: 09/28/1992
• Status: Expired due to Fees

• Current Assignee: Horiba Limited
• Original Assignee: Horiba Limited
• Inventors: Kojima, Junji, Mori, Takeshi, Ohkawa, Hiromi
• Primary Examiner(s): Swarthout, Brent A.
• Assistant Examiner(s): MANNAVA, ASHOK K
• Application Number:
  US08/126,356
• Time in Patent Office: 1,033 Days
• Field of Search: 340/870.13, 340/825.06, 340/870.16, 340/870.17, 340/870.01-870.03, 340/500, 340/511, 455/68-70, 455/103, 455/38.3, 370/95.1, 370/95.3
• US Class Current: 340/870.01
• CPC Class Codes: G08C 19/28 using pulse code

Abstract

A remote monitoring system for instrumentation that is capable of measuring certain characteristics of a process such as a pH value includes an instrument for providing a measurement output signal which can be stored. A comparison circuit can compare the output signal with a predetermined value. A transmitter can transmit when the output signal exceeds the predetermined value, and a receiver can receive the output signal and convert it into a measured result. The instrumentation can be pulled from the receiver and the output signals can be encoded to identify a particular instrument with distinct transmission time periods available in a plurality of transmitting channels.

Claims

1. A remote monitoring system for instrumentation measuring certain characteristics of a process comprising:

an instrument for providing a measurement of a process and providing output signals of measurement values;

means for storing a datum value representative of the measurement value of the last transmitted output signal V_n-1 ;

comparing means for comparing a current output signal V_n with the stored datum value V_n-1 of a previous output signal and providing a comparison value signal;

a transmitter connected to the instrument for wirelessly transmitting an output signal;

means for causing the transmitter to transmit a current output signal when the comparison value signal is equal to or greater than a predetermined stored value X in accordance with the following equation;

space="preserve" listing-type="equation">|V.sub.n -V.sub.n-1 |≧

X; and

a receiver means for receiving the transmitted current output signal to provide a measured result of the process.

2. The invention of claim 1, further including means for periodically transmitting, at set time periods, a current output signal equal to or greater than a predetermined value.

3. The invention of claim 1, further including means for converting the measurement output signals at the transmitter into digital values.

4. The invention of claim 1, further including means for providing, at the transmitter, a plurality of different transmission channels.

5. The invention of claim 4, further including means for providing set transmission periods that are distinct from each other for each transmission channel.

6. The invention of claim 1, further including receiving means connected to the transmitter for wirelessly receiving input signals to cause a specific transmission by the transmitter of a current output signal.

7. The invention of claim 1, further including means connected to the transmitter for encoding an instrument identification code with the transmission of the output signal.

8. The invention of claim 1 wherein the instrumentation includes a pH-measuring electrode for providing an output signal representative of a pH value.

9. In a remote monitoring system for a pH meter apparatus comprising a plurality of sensors for providing measurements of pH and providing output signals, a communication system comprising:

means for storing a datum value representative of the measurement value of the last transmitted output signal V_n-1 ;

comparing means for comparing a current output signal V_n with the stored datum value V_n-1 of a previous output signal and providing a comparison value signal;

a transmitter connected to the sensor for wirelessly transmitting an output signal;

means for causing the transmitter to transmit a current output signal when the comparison value signal is equal to or greater than a predetermined value X in accordance with the following equation;

space="preserve" listing-type="equation">|V.sub.n -V.sub.n-1 |≧

X; and

a receiver means for receiving the transmitted current output signals from each transmitter; and

means for processing the output signals from the receiver means to provide a pH value for each sensor.

10. The invention of claim 9, further including means for periodically transmitting, at set time periods, a current output signal equal to or greater than a predetermined value from each sensor.

11. The invention of claim 9, further including means for converting the measurement output signals at each transmitter into digital values.

12. The invention of claim 9, further including means for providing, at each transmitter, a plurality of different transmission channels.

13. The invention of claim 12, further including means for providing set transmission periods that are distinct from each other for each transmission channel.

14. The invention of claim 9, further including receiving means, connected to each transmitter, for wirelessly receiving input signals to cause a specific transmission by the transmitter of a current output signal.

15. The invention of claim 9, further including means, connected to each transmitter, for encoding an instrument identification code with the transmission of the output signal.