Liquid level sensor frequency output system

• US 8,650,949 B1
• Filed: 03/10/2011
• Issued: 02/18/2014
• Est. Priority Date: 03/11/2010
• Status: Active Grant

• Current Assignee: S.J. Electro Systems, Inc.
• Original Assignee: S.J. Electro Systems, Inc.
• Inventors: Ostlie, Mark R., Calkins, Lou R.
• Primary Examiner(s): Williams, Hezron E
• Assistant Examiner(s): NGUYEN, HOANG T
• Application Number:
  US13/044,836
• Time in Patent Office: 1,076 Days
• Field of Search: 73/17.3, 732/90.V, 73/18.2, 73/18.3, 732/90.R, 733/05, 733/13, 733/14, 733/17, 340/612, 340614-625
• US Class Current: 73/290.R
• CPC Class Codes: G01L 19/0645 using isolation membranes, specially adapted for protection
• CPC Class Codes: G01L 19/149 of immersion sensor, e.g. where the sensor is immersed in the measuring medium or for in vivo measurements, e.g. by using catheter tips

Abstract

A liquid level sensor frequency output system for efficiently communicating a liquid level with reduced power and increased accuracy. The liquid level sensor frequency output system generally includes a sensor that determines a liquid level, a transmitter in communication with the sensor that converts the level data to a signal having a frequency representing the liquid level, and a receiver that receives the signal, wherein the receiver calculates the liquid level based on the frequency of the signal. The calculated liquid level by the receiver can be transmitted to an output device such as a display, switch, warning system or pump.

Claims

1. A liquid level sensor frequency output system, comprising:

a sensor that determines a liquid level within a tank and transforms said liquid level into a level output;

a transmitter in communication with said sensor, wherein said transmitter converts said level output to a signal having a frequency representing said liquid level and transmits said signal, wherein said frequency is calculated based on said liquid level; and

a receiver that receives said signal, wherein said receiver calculates said liquid level based on said frequency of said signal;

wherein said transmitter communicates to said receiver an identity for said transmitter.

2. The liquid level sensor frequency output system of claim 1, wherein said level output is comprised of a direct current signal.

3. The liquid level sensor frequency output system of claim 1, wherein said signal is communicated via a communication cable between said transmitter and said receiver.

4. The liquid level sensor frequency output system of claim 1, wherein said signal is communicated wirelessly between said transmitter and said receiver.

5. The liquid level sensor frequency output system of claim 1, wherein said frequency is substantially linear with respect to said liquid level.

6. The liquid level sensor frequency output system of claim 1, wherein said frequency is non-linear with respect to said liquid level.

7. The liquid level sensor frequency output system of claim 1, wherein a frequency range of said frequency represents said identity for said transmitter, wherein said identity is comprised of a level range for said transmitter.

8. The liquid level sensor frequency output system of claim 1, including an initiation signal communicated by said transmitter to said receiver indicating said identity for said transmitter, wherein said identity is comprised of a level range for said transmitter.

9. The liquid level sensor frequency output system of claim 1, wherein said frequency is calculated based on said level output having a first slope and a second slope, wherein said first slope represents a first level for said level output and wherein said second slope represents a second level for said level output, wherein said first slope is different from said second slope.

10. The liquid level sensor frequency output system of claim 9, wherein said first slope is greater than said second slope.

11. The liquid level sensor frequency output system of claim 1,

including an output device in communication with said receiver.

12. A liquid level sensor frequency output system, comprising:

a sensor that determines a liquid level within a tank and transforms said liquid level into a level output, wherein said level output is comprised of a direct current signal;

a transmitter in communication with said sensor, wherein said transmitter converts said level output to a signal having a frequency representing said liquid level and transmits said signal, wherein said frequency is calculated based on said liquid level;

wherein said frequency is substantially linear with respect to said liquid level;

wherein a frequency range of said frequency represents an identity for said transmitter,

wherein said identity is comprised of a level range for said transmitter;

a receiver that receives said signal, wherein said receiver calculates said liquid level based on said frequency of said signal; and

an output device in communication with said receiver.

13. A liquid level sensor frequency output system, comprising:

a sensor that determines a liquid level within a tank and transforms said liquid level into a level output;

a transmitter in communication with said sensor, wherein said transmitter converts said level output to a signal having a frequency representing said liquid level and transmits said signal, wherein said frequency is calculated based on said liquid level; and

a receiver that receives said signal, wherein said receiver calculates said liquid level based on said frequency of said signal;

wherein said frequency is calculated based on said level output having a first slope and a second slope, wherein said first slope represents a first level for said level output and wherein said second slope represents a second level for said level output, wherein said first slope is different from said second slope.

14. The liquid level sensor frequency output system of claim 13, wherein said first slope is greater than said second slope.

15. The liquid level sensor frequency output system of claim 13, wherein said level output is comprised of a direct current signal.

16. The liquid level sensor frequency output system of claim 13, wherein said signal is communicated wirelessly between said transmitter and said receiver.

17. The liquid level sensor frequency output system of claim 13, wherein said frequency is substantially linear with respect to said liquid level.

18. The liquid level sensor frequency output system of claim 13, wherein said frequency is non-linear with respect to said liquid level.

19. The liquid level sensor frequency output system of claim 13, wherein a frequency range of said frequency represents said identity for said transmitter, wherein said identity is comprised of a level range for said transmitter.

20. The liquid level sensor frequency output system of claim 13, including an initiation signal communicated by said transmitter to said receiver indicating an identity for said transmitter, wherein said identity is comprised of a level range for said transmitter.