JPH044230Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a potential sensor used for detecting the strength of an electrostatic field, measuring the amount of charge, and the like.

[Prior art]

Potential sensors generally have a case with a detection hole for introducing the lines of electric force radiated from the object to be measured, and a chopper that periodically cuts the lines of electric force entering the case and converts them into alternating lines of electric force. an electrode that receives the alternating electric lines of force and outputs an alternating current signal;
It consists of an amplifier circuit that amplifies the alternating current signal detected by this electrode, and a drive circuit that drives the chopper section.

In FIGS. 1a and 1b showing a conventional potential sensor, a driving voltage ceramic 6 is installed in the chopper part.
A tuning fork 2 is used, which has a tuning fork 2 glued thereto, and the electric lines of force 7 are cut at the tip of the tuning fork 2. The electrode 3 is fixed to the substrate 8 and placed behind the tip of the tuning fork.
Further, the amplifying circuit 10 for the AC signal detected by the electrode 3 and the driving circuit 11 for the tuning fork 2 are also connected to the substrate 8.
is placed above. These chopper parts, electrodes, amplifier circuits, and drive circuits are housed in a case 1 having a detection hole and a base 4 to which a substrate 8 is attached. A potential sensor with such a conventional configuration is
Since the chopper section, the amplifier circuit, and the drive circuit are arranged on the substrate 8 in a plane with respect to the surface facing the object to be measured, the cross-sectional area facing the object to be measured becomes large. Therefore, when a conventional potential sensor is built into a device, a large space is required for installation, which has the disadvantage of interfering with the mounting of other components.

[Purpose of invention]

An object of the present invention is to provide a potential sensor that eliminates the above-mentioned drawbacks.

[Structure of the idea]

The potential sensor of the present invention includes a case having a detection hole that introduces the electric lines of force from the object to be measured, and a chopper that periodically cuts the electric lines of force introduced from the detection hole and converts them into alternating lines of electric force. and a first electrode mounted in the case that receives the alternating electric lines of force and outputs an alternating current signal, and is arranged in the case so that the chopper part cuts the electric lines of force from the detection hole.
A second board is mounted with an amplifier circuit for amplifying the alternating current signal and a drive circuit for driving the chopper section, and is disposed in the case so that the board surface is perpendicular to the board surface of the first board. It consists of a substrate.

〔Example〕

Next, the present invention will be explained in detail with reference to the drawings.

In FIGS. 2a and 2b showing an embodiment of the present invention, on a first substrate 8 is a tuning fork 2 to which an electrode 3 and a driving voltage ceramic 6, which is a chopper part, are bonded.
Further, on the second substrate 9, an amplifying circuit 10 for an AC output signal and a driving circuit 11 for the chopper portion are provided. Further, the substrate 8 and the substrate 9 are arranged in the case 1 so as to be perpendicular to each other, and intersect at one side of each. Further, a ground terminal 5, a power terminal 12, and an output terminal 13 pass through the base 4 and are connected to an internal circuit.

In this embodiment, the only surface facing the object to be measured is the substrate surface of the substrate 8 on which the tuning fork and electrodes are arranged, and the substrate surface of the substrate 9 on which the amplifier circuit and drive circuit are mounted, which requires a large substrate area, is Since it is perpendicular to the surface facing the object to be measured, the cross-sectional area can be reduced, and it does not take up as much space as conventional methods.
Additionally, the amplifier circuit and drive circuit can be built into the same case, and no cables are required to connect the electrodes to the circuit, so it is not affected by external noise. Therefore, the operation of the chopper section is stabilized, and the accuracy of the output voltage of the potential sensor is improved.

[Effect of idea]

As described above, the present invention has the advantage that it does not take up much space when mounting the device.

[Brief explanation of the drawing]

1A and 1B are a plan sectional view and a front sectional view, respectively, showing a conventional potential sensor, and FIGS. 2A and 2B are a plan sectional view and a front sectional view, respectively, showing an embodiment of the present invention. In the figure, 1...case, 2...tuning fork, 3...
...Electrode, 4...Base, 5...Earth terminal, 6...
... Piezoelectric ceramics, 7... Electric lines of force, 8, 9...
... board, 10 ... amplifier circuit, 11 ... drive circuit,
12...Power terminal, 13...Output terminal.

Claims (1)

[Claims for Utility Model Registration] A case having a detection hole that introduces the lines of electric force from the object to be measured into the inside, and a case that vibrates at a constant period and periodically cuts the lines of electric force introduced from the detection hole. equipped with a chopper part that converts into alternating electric lines of force and an electrode that receives the alternating electric lines of force and outputs an alternating current signal, so that the chopper part cuts the electric lines of force from the detection hole;
A first substrate having a first width is disposed in the case horizontally with the vibration direction of the tipper part, and an amplifier circuit that amplifies the alternating current signal and a drive circuit that drives the tipper part are mounted. , a second substrate having a second width larger than the first width, the substrate surface of which is orthogonal to the substrate surface of the first substrate, and which is arranged in the case so as to intersect with the substrate surface of the first substrate; A potential sensor comprising: a substrate;