Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
186 words
An apparatus for detecting dielectric constant of a fuel, said apparatus comprising: means for applying a high frequency voltage signal; means for subjecting the high frequency voltage signal from said applying means to resonance corresponding to the dielectric constant of the fuel; a resistor having one end connected in series to said subjecting means and the other end to which the high frequency voltage signal is applied from said applying means; bias control means connected to the other terminal of said subjecting means for applying a bias DC voltage to said subjecting means; detecting means connected between said one and the other ends of said resistor for detecting a phase shift between said high frequency voltage signal of said applying means and a voltage signal provided in a connecting line between said subjecting means and said resistor; control means for controlling the high frequency voltage signal from said applying means to adjust the phase shift detected by said detecting means to a first predetermined value, at least one of said applying means and control means producing a signal representative of the dielectric constant of the fuel.
Claim 2
Independent Claim
186 words
An apparatus for detecting dielectric constant of a fuel, said apparatus comprising: means for applying a high frequency voltage signal; means for subjecting the high frequency voltage signal from said applying means to resonance corresponding to the dielectric constant of the fuel; a resistor having one end connected in series to said subjecting means and the other end to which the high frequency voltage signal is applied from said applying means; bias control means connected to the other terminal of said subjecting means for applying a bias DC voltage to said subjecting means; detecting means connected between said one and the other ends of said resistor for detecting a phase shift between said high frequency voltage signal of said applying means and a voltage signal provided in a connecting line between said subjecting means and said resistor; control means for controlling the high frequency voltage signal from said applying means to adjust the phase shift detected by said detecting means to a first predetermined value, at least one of said applying means and control means producing a signal representative of the dielectric constant of the fuel.
Claim 3
Dependent Claim
69 words
An apparatus according to claim 1, wherein said detecting means includes waveform shaping means to convert said voltage signal in a sinusoidal waveform provided in the connecting line between said subjecting means and said resistor to a corresponding square waveform signal, and said detecting means compares the square waveform signal from said waveform shaping means with the high frequency voltage signal of said applying means in a square waveform.
Claim 4
Dependent Claim
59 words
An apparatus according to claim 2, wherein said bias control means includes converting means for converting said square waveform signal from said waveform shaping means to a direct current voltage signal representative of a duty thereof, said bias control means adjusting said bias DC voltage to cause the voltage signal representative of the duty to become second predetermined value.
Claim 5
Dependent Claim
18 words
An apparatus according to claim 1, wherein said first predetermined value of the phase shift is 0 degree.
Claim 6
Dependent Claim
15 words
An apparatus according to claim 3, wherein said second predetermined value represent a duty 50%.
Claim 7
Dependent Claim
57 words
An apparatus according to claim 1, wherein said applying means including a section for applying a high frequency voltage signal to said resistor and a section for applying a reference high frequency voltage signal to said detecting means to be compared with said voltage signal provided in the connecting line between said subjecting means and said resistor.
Claim 8
Dependent Claim
122 words
An apparatus according to claim 6, further comprising reference phase comparing means for detecting a reference phase shift between the output of said high frequency signal applying section with the output of said reference high frequency signal applying section, wherein said control means controls the high frequency voltage signal from said applying means to adjust the phase shift detected by said detecting means to the reference phase shift detected by said reference phase comparing means as the first predetermined value, at least one of the output frequency of said high frequency applying section, the output frequency of said reference high frequency applying section and the control output of said control means producing a signal representative of the dielectric constant of said fuel.
Claim 9
Dependent Claim
17 words
An apparatus according to claim 1, wherein said fuel includes at least one of gasoline and alcohol.