LCC-based fluid-level detection sensor

• US 6,949,758 B2
• Filed: 10/07/2002
• Issued: 09/27/2005
• Est. Priority Date: 10/19/2001
• Status: Expired due to Fees

• Current Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Shi, Zhong-You, Marlow, C. Allen
• Primary Examiner(s): Porta, David
• Assistant Examiner(s): MONBLEAU, DAVIENNE N
• Application Number:
  US10/265,954
• Publication Number:
  US 20030075698A1
• Time in Patent Office: 1,086 Days
• Field of Search: 340/450, 340/618, 340/619, 340555-557, 340/904, 356/436, 732/93
• US Class Current: 250/577
• CPC Class Codes: F02B 75/22 with cylinders in V, fan, or star arrangement
• CPC Class Codes: F02B 77/085 with sensors measuring combustion processes, e.g. knocking, pressure, ionization, combustion flame
• CPC Class Codes: F02B 77/089 relating to engine temperature concerning coolant temperature F01P11/16
• CPC Class Codes: F02D 2400/18 Packaging of the electronic circuit in a casing
• CPC Class Codes: F02D 41/28 Interface circuits
• CPC Class Codes: F05C 2225/08 Thermoplastics
• CPC Class Codes: G01F 23/2925 using electrical detecting means
• CPC Class Codes: G01L 11/02 by optical means
• CPC Class Codes: G01L 23/16 by photoelectric means
• CPC Class Codes: G01N 21/431 Dip refractometers, e.g. using optical fibres
• CPC Class Codes: G02B 2006/12104 Mirror; Reflectors or the like
• CPC Class Codes: G02B 2006/12109 Filter
• CPC Class Codes: G02B 6/12004 Combinations of two or more optical elements
• CPC Class Codes: G02B 6/12007 forming wavelength selective elements, e.g. multiplexer, demultiplexer
• CPC Class Codes: G02B 6/122 Basic optical elements, e.g. light-guiding paths
• CPC Class Codes: G02B 6/4298 coupling with non-coherent light sources and/or radiation detectors, e.g. lamps, incandescent bulbs, scintillation chambers
• CPC Class Codes: G02B 6/43 Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections
• CPC Class Codes: G08C 2201/31 Voice input
• CPC Class Codes: G08C 2201/41 Remote control of gateways
• CPC Class Codes: G08C 23/02 using infrasonic, sonic or ultrasonic waves
• CPC Class Codes: Y10S 250/904 : with single light guide element to guide light in a continuous path

Abstract

A non-mechanical fluid level sensor based on light communication channel (LCC) technology. In a preferred embodiment, one end of the LCC is connected to a signal source while another end is connected to a sensor. The LCC is dipped in a fluid container and a signal propagates and undergoes internal reflection through the LCC towards one of its ends which is connected to the sensor. The fluid level is detected preferably by measuring the intensity of the signal reflected with the LCC that reaches a sensor. Different fluid levels preferably correspond to linearly varying detected signal intensities. A main LCC bus may communicate remotely with the sensor without wiring or other electrical connectors.

Claims

1. A fluid level detection system comprising:

a signal source,

an LCC structure that extends into a fluid container with a first end of the LCC structure being connected to the signal source,

wherein the LCC structure is polyethylene terephthalate, polypropylene, polyethylene or polycarbonate, and the LCC structure is formed as a thin sheet, and

at least one sensor that receives a signal from the signal source and is connected to a second end of the LCC structure, wherein a signal from the signal source propagates through the LCC structure.

2. The fluid level detection system of claim 1, wherein the signal source is an infrared light source, visible light source, ultraviolet light source, an LED, or an RF source.

3. The fluid level detection system of claim 1, wherein the indices of refraction of an LCC material and a fluid inside a fluid container give rise to a negligible signal intensity that reaches the at least one sensor when the fluid container is full.

4. The fluid level detection system of claim 1, wherein the at least one sensor transmits a signal relating to a fluid level through an LCC bus.

5. The fluid level detection system of claim 1, wherein the at least one sensor transmits a signal to an electronic system or a display panel of a vehicle.

6. The fluid level detection system of claim 1, wherein a surface of the LCC structure is coated with a reflective or a protective coating.

7. A fluid level detection system comprising:

a signal source,

an LCC structure that extends into a fluid container with a first end of the LCC structure being connected to the signal source, and through which a signal from the signal source propagate,

wherein the LCC structure is polyethylene terephthalate, polypropylene, polyethylene or polycarbonate, and the LCC structure is formed as a thin sheet,

at least one sensor that is connected to a second end of the LCC structure and that receives a signal from the signal source, and

an LCC bus to which the at least one sensor is connected, and

wherein the at least one sensor transmits a signal via the LCC bus to an electronic system or a display panel of a vehicle.

8. The fluid level detection system of claim 7, wherein the signal source is an infrared light source, visible light source, ultraviolet light source, an LED, or an RF source.

9. The fluid level detection system of claim 7, wherein the indices of refraction of an LCC material and a fluid inside a fluid container give rise to a negligible signal intensity that reaches the at least one sensor when the fluid container is full.

10. The fluid level detection system of claim 7, wherein a surface of the LCC structure is coated with a reflective or a protective coating.

11. A fluid level detection system comprising:

a signal source,

an LCC structure that extends into a fluid container, with a first end of the LCC structure being connected to the signal source, and through which a signal from the signal source propagates,

wherein the LCC structure is polyethylene terephthalate, polypropylene, polyethylene or polycarbonate, and the LCC structure is formed as a thin sheet,

at least one sensor connected to a second end of the LCC, wherein the at least one sensor receives a signal that propagates through the LCC, and

an LCC bus connected to the at least one sensor to which the at least one sensor transmits a signal relating to a fluid level,

wherein the at least one sensor transmits a signal via an LCC bus to an to an electronic system, and the electronic system processes the signal relating to the fluid level or transmits the signal relating to the fluid level to another electronic system or a display panel of a vehicle.

12. The fluid level detection system of claim 11, wherein the signal source is an infrared light source, visible light source, ultraviolet light source, an LED, or an RF source.

13. The fluid level detection system of claim 11, wherein the indices of refraction of an LCC material and a fluid inside a fluid container give rise to a negligible signal intensity that reaches the at least one sensor when the fluid container is full.