JPH01137419U

JPH01137419U -

Info

Publication number: JPH01137419U
Application number: JP3479788U
Authority: JP
Priority date: 1988-03-16
Filing date: 1988-03-16
Publication date: 1989-09-20
Anticipated expiration: 2003-03-16
Also published as: JPH0547382Y2

Description

[Brief explanation of drawings]

第１図ａ〜ｄは、それぞれ本考案による渦信号
変換回路を示す図、第２図ａ〜ｄは、それぞれ第
１図におけるシールド導線のシールド処理例を示
す図、第３図は、本考案が適用される渦流量計の
一例を説明するための図である。１…流管、２…渦発生体、２１…圧力検知室、
２２，２３…圧力導入口、６…円筒体、７…円柱
体、Ａｓ，Ｂｓ…シールド、Ａｃ，Ｂｃ…導線、
Ｗ…絶縁材、Ａｐ，Ｂｐ，Ｍｐ…金属管。 1A to 1D are diagrams showing a vortex signal conversion circuit according to the present invention, FIGS. 2A to 2D are diagrams each showing an example of shielding treatment of the shield conductor in FIG. FIG. 2 is a diagram for explaining an example of a vortex flowmeter to which this is applied. 1... Flow tube, 2... Vortex generator, 21... Pressure detection chamber,
22, 23...Pressure introduction port, 6...Cylindrical body, 7...Cylindrical body, As, Bs...Shield, Ac, Bc...Conducting wire,
W...Insulating material, Ap, Bp, Mp...Metal tube.

Claims

[Claims for Utility Model Registration] 1. A detection means for detecting a vortex generated by a vortex generating body in accordance with the flow as a fluctuating pressure due to the vortex, the detection means having a main part fixed to the vortex generating body. A differential capacitance system is used, which consists of a fixed electrode fixed to a part, etc., and a movable electrode that forms a variable capacitance between the fixed electrode and the fixed electrode in response to the fluctuating pressure. Or, it consists of a common electrode with one of the movable electrodes grounded, and first and second electrodes sandwiching the common electrode, and the capacitance between the conductor and the shield connected to the first and second electrodes. a common DC power supply for charging the capacitance to be measured via the shielded conductor; a switch means for charging and switching the charged charge to a discharge circuit; It consists of a switching means that switches at an extremely fast cycle, and a differential amplifier circuit that converts the discharge current into a voltage proportional to the capacitance and finds the difference between each voltage, and connects the shield in parallel with the shield conductor. eddy signal conversion characterized in that the voltage corresponding to the capacitance between the shield and the conductor in the shield conductor is canceled by grounding, and the vortex signal is detected as a voltage value corresponding to the true differential capacitance to be tested. vessel. 2 The shield of the shielded conductor wire is a metal conduit of equal diameter, the conductor is closely fixed concentrically with an insulating material within the metal conduit, and the two metal conduits connected to the first and second electrodes are made parallel. 2. A vortex signal converter according to claim 1, characterized in that they are closely spaced. 3. The shield in the shielded conductor wire is a single metal conduit with the same diameter, and two conductive wires that are grounded to the first and second electrodes are inserted into the metal conduit in parallel and axially symmetrically. 2. The vortex signal converter according to claim 1, wherein the vortex signal converter is fixed with an insulating material. 4. The vortex signal converter according to claim 1, wherein the two shielded conductive wires are twisted together to form an integral structure.