JP2016176913A5 - - Google Patents

Description

Next, the operation of dielectric constant detection will be described. In this embodiment, the dielectric constant of the toner alone contained in the developer is detected. FIG. 22 is a timing chart for explaining the operation of dielectric constant detection according to the present invention. In this embodiment, the first oscillator circuit is composed of a coil L1 and the capacitor C11 in FIG. 16 (the first coil 1 and the first capacitor 71), the coil L 2及 beauty capacitor C12 in FIG. 16 (the second coil 2 And the second capacitor 72) constitute a second oscillation circuit.

In the above example, the reference capacitor is formed by using the plus electrode 74 and the virtual electrode. However, the reference capacitor may be formed by using a pair of electrodes. For this, a pair of electrodes 72a and 72b as shown in FIG.
By the way, in a coil, an electrostatic capacitance component exists between adjacent lines. Therefore, if this capacitance component is used, it is possible to function as a dielectric constant sensor without providing the electrodes as described above. That is, a dielectric constant sensor can be constructed with the configuration shown in FIGS.
In such an example, the first coil 1 corresponds to the coil L1 and the capacitor C11 of FIG. 16, and the first coil 1 alone constitutes an oscillation circuit, and the second coil 2 corresponds to the coil L2 and the capacitor C12 of FIG. Correspondingly, an oscillation circuit is constituted by the second coil 2 alone. Then, the oscillation frequency measured in the first oscillation circuit for detection having the first coil 1 (derived from the capacitance between the lines of the first coil 1) and the second reference for the second coil 2 are provided. A difference from the measured oscillation frequency (derived from the capacitance between the lines of the second coil 2) in the oscillation circuit is calculated, and the calculated difference is converted into a dielectric constant to obtain a change amount of the dielectric constant.

Claims (6)

In a dielectric constant sensor that detects the dielectric constant of an object to be detected,
A first oscillation circuit that oscillates including a first capacitor disposed in a region where the detected object exists;
A second oscillation circuit that oscillates including a second capacitor disposed in a region where the object to be detected does not exist;
Measuring means for measuring an oscillation frequency in each of the first oscillation circuit and the second oscillation circuit;
Calculating means for calculating a difference between oscillation frequencies measured by the measuring means;
A dielectric constant sensor comprising: conversion means for converting a difference calculated by the calculation means into a dielectric constant. The first capacitor has a pair of electrodes provided in a region where the object to be detected exists, and the second capacitor has a pair of electrodes provided in a region where the object to be detected does not exist. The dielectric constant sensor according to claim 1 . Wherein the first capacitor has a dielectric constant sensor according to claim 1, characterized in that it has a single electrode provided in a region where the object to be detected is present. In a dielectric constant detection method for detecting a dielectric constant of an object to be detected,
A first capacitor is disposed in a region where the detected object is present, and a second capacitor is disposed in a region where the detected object is not present,
Measure the oscillation frequency of the oscillation circuit that oscillates including the first capacitor and the oscillation frequency of the oscillation circuit that oscillates including the second capacitor,
Calculate the difference between the measured oscillation frequencies,
A dielectric constant detection method, wherein the calculated difference is converted into a dielectric constant. A magnetic permeability / dielectric constant sensor for selectively detecting the magnetic permeability or dielectric constant of an object to be detected,
A first oscillation circuit that oscillates including a coil and a capacitor;
A second oscillation circuit that oscillates including a coil and a capacitor different from the coil and the capacitor of the first oscillation circuit;
Measuring means for measuring an oscillation frequency in each of the first oscillation circuit and the second oscillation circuit;
Calculating means for calculating a difference between oscillation frequencies measured by the measuring means;
A magnetic permeability / dielectric constant sensor comprising: conversion means for converting the difference calculated by the calculation means into magnetic permeability or dielectric constant. A magnetic permeability / dielectric constant detection method for selectively detecting the magnetic permeability or dielectric constant of an object to be detected,
An oscillation frequency of a first oscillation circuit that oscillates including a coil and a capacitor and an oscillation frequency of a second oscillation circuit that oscillates including a coil and a capacitor different from the coil and capacitor of the first oscillation circuit are measured. ,
Calculate the difference between the measured oscillation frequencies,
A magnetic permeability / dielectric constant detection method, wherein the calculated difference is converted into a magnetic permeability or a dielectric constant.