# US 7,911,595 B2 · Liquid fuel property detection system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,911,595 B2 - Document ID: US7911595B2 - Status: Granted - Kind: B2 - Application number: 12/626,723 - Filed: 2009-11-27 - Published: 2010-06-24 - Granted: 2011-03-22 - Earliest claimed: 2008-12-18 - Assignees: Denso Corporation; Nippon Soken, Inc. - Inventors: Tetsuro Serai; Kazuki Matsuo; Hiroshi Nakamura - Web page: https://patentgrep.com/patent/US7911595B2 ## CPC - G01N 21/359: using near infrared light - G01J 3/10: Arrangements of light sources specially adapted for spectrometry or colorimetry - G01J 3/42: Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry (beam switching arrangements G01J3/08) - G01N 21/314: {with comparison of measurements at specific and non-specific wavelengths (dual wavelength spectrometry G01J3/427)} - G01N 21/3577: for analysing liquids, e.g. polluted water - G01N 33/2835: {Specific substances contained in the oils or fuels} - G01J 2003/104: {Monochromatic plural sources} - G01J 2003/1208: {Prism and grating} - G01N 21/85: Investigating moving fluids or granular solids - G01N 2021/0314: {Double pass, autocollimated path} - G01N 2021/5961: {using arrays of sources and detectors} - G01N 2021/5969: {Scanning of a tube, a cuvette, a volume of sample} - G01N 2201/0627: Use of several LED's for spectral resolution - G01N 2201/1293: resolving multicomponent spectra - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) ## Abstract A liquid fuel property detection apparatus includes a fuel passage, a light emitting device for emitting a light including a plurality of predetermined wavelengths toward the fuel in the passage, a light receiving device for receiving the light passing through the fuel, and a calculation unit for calculating the concentration of at least one of aroma, paraffin and olefin, which are hydrocarbon component components contained in the fuel. The calculation unit calculates the concentration of a specific component, which is one of aroma, paraffin and olefin, based on the reference transmittance of light in the specific component and the actual transmittance calculated from the amount of light emitted by the light emitting device and the amount of light received by the light receiving device with respect to each wavelength of the light. ## Claims ### Claim 1 A liquid fuel property detection apparatus comprising: a passage, in which liquid fuel flows; a light emitting device for emitting a light transversely toward the fuel in the passage, the light including a plurality of predetermined wavelengths; a light receiving device for receiving the light including the plurality of predetermined wavelengths, the light being transmitted through the fuel; and a calculation unit for calculating concentration of at least one specific component of aroma component, paraffin component and olefin component, which are hydrocarbon series constituent substances contained in the fuel, wherein the calculation unit is configured to calculate the concentration of a specific component of at least one of the aroma component, the paraffin component and the olefin component based on a characteristic of reference transmittance of the light in the specific component relative to wavelength of the light and actual transmittance of the light, which is calculated from an amount of the light including the plurality of predetermined wavelengths emitted from the light emitting device and an amount of the light received by the light receiving device. ### Claim 2 (depends on 1) The liquid fuel property detection apparatus according to claim 1, wherein: the light emitting device includes a plurality of light emitting elements, which are less in number than a plurality of light receiving elements of the light receiving device, and a light combining device for combining light beams of the plurality of light emitting elements to produce a composite light; and a light separating device is provided for separating the composite light transmitted through the fuel into a plurality of light beams to be directed to the plurality of receiving elements. ### Claim 3 (depends on 1) The liquid fuel property sensor according to claim 1, wherein: the light emitting device includes a plurality of light emitting elements, which are driven to emit a plurality of light beams of the predetermined wavelengths, respectively, at different time points; and the light receiving device includes a single light receiving element, which receives the plurality of light beams individually. ### Claim 4 (depends on 1) The liquid fuel property detection apparatus according to claim 1, wherein: the light emitting device and the light receiving device are positioned at a same side relative to the passage; and a reflecting device is positioned at a side opposite the light emitting device relative to the passage so that the light emitted from the light emitting device is transmitted through the fuel in the passage, reflected by the light reflecting device, transmitted through the fuel in the passage again and received by the light receiving device. ### Claim 5 (depends on 1) The liquid fuel property detection apparatus according to claim 1, wherein: the calculation unit is configured to calculate the concentration of the specific component by substituting the calculated actual transmittance for a prediction relation determined by multivariate analysis technique based on the characteristic of transmittance of the light in the specific component relative to wavelength of the light. ### Claim 6 (depends on 1) The liquid fuel property detection apparatus according to claim 1, wherein: the plurality of predetermined wavelengths includes a wavelength, at which the reference transmittance varies most depending on a difference in the concentration of the specific component. ### Claim 7 (depends on 6) The liquid fuel property detection apparatus according to claim 6, wherein: the plurality of predetermined wavelengths further include a wavelength, at which the reference transmittance varies least depending on the difference in the concentration of the specific component. ### Claim 8 (depends on 1) The liquid fuel property detection apparatus according to claim 1, wherein: the plurality of predetermined wavelengths includes a wavelength, at which the reference transmittance takes a local peak value with respect to each concentration of the specific component.