CN205826068U

CN205826068U - The capacitive liquid level sensor that can automatically calibrate

Info

Publication number: CN205826068U
Application number: CN201620632984.XU
Authority: CN
Inventors: 顾新; 顾一新
Original assignee: DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL Ltd
Current assignee: Guangdong Zhengyang Sensor Technology Co ltd
Priority date: 2016-06-24
Filing date: 2016-06-24
Publication date: 2016-12-21
Anticipated expiration: 2026-06-24

Abstract

This utility model discloses a kind of capacitive liquid level sensor that can automatically calibrate, and includes trocar sheath, shaft member and two electrode slices；This shaft member is arranged in trocar sheath, and this two electrode slice is symmetricly set in the outer surface of shaft member axially extending along shaft member, is formed with gap and constitutes two electric capacity between two electrode slices and the inwall of trocar sheath.Thereby, by two electrode slice symmetry volumes overlay on the outer surface of shaft member, utilizing and be formed with gap between two electrode slices and the inwall of trocar sheath and constitute two electric capacity, when the difference maximum of two capacitances when, now liquid level is just at 1/2 liquid level of whole sensor；When the difference of two capacitances is minimum, simultaneously the when of two capacitances also minimum, now liquid level is just at the minimum liquid level of whole sensor；The capacitance of full position can be calculated according to this capacitance at two, can realize automatically calibrating；This utility model simple in construction, convenient for production, low cost, and the degree of accuracy calibrated is high, is worth of widely use.

Description

The capacitive liquid level sensor that can automatically calibrate

Technical field

This utility model relates to liquid level sensor art, refers in particular to a kind of capacitance liquid level that can automatically calibrate sensing Device.

Background technology

Traditional capacitance level transducer structure is: a metal tube and a metal bar are vertically arranged, coaxial sleeve Dress, as two pole plates of capacitor, their two ends respectively with base, upper cover is fixing is connected, metal tube and metal bar it Between formed a constant volume space, fluid to be measured can enter this space, is filled with two media in space, and bottom is fluid to be measured, Top is air, when liquid level generation eustasy, owing to the dielectric coefficient of fluid to be measured, air is different, and the capacity of capacitor Change the most therewith, therefore, liquid level can be characterized by capacitance.

But, now with capacitance level transducer can not automatically calibrate, measure media variations time need school again Standard, otherwise accuracy in measurement can decline；Although some capacitance level transducers use the automatic calibration program of five-part form, but this Calibration program electrode segment is more, produces complexity, and cost is high.Therefore, it is necessary to current capacitance level transducer is carried out Improve.

Utility model content

In view of this, this utility model is for the disappearance of prior art existence, and its main purpose is to provide one can be automatic The capacitive liquid level sensor of calibration, it can effectively solve existing capacitance level transducer and can not automatically calibrate or automatic school Quasi-project makes to produce the problem that complicated cost is high.

For achieving the above object, this utility model uses such as purgation technical scheme:

A kind of capacitive liquid level sensor that can automatically calibrate, includes trocar sheath, shaft member and two electrode slices；This shaft member sets Being placed in trocar sheath, this two electrode slices symmetry volume overlays on the outer surface of shaft member axially extending along shaft member, and two electrode slices are with outer It is formed with gap between the inwall of sleeve pipe and constitutes two electric capacity.

As a kind of preferred version, described shaft member is coaxially disposed with trocar sheath.

As a kind of preferred version, the open at both ends up and down of described trocar sheath.

As a kind of preferred version, described shaft member is hollow structure, its upper and lower both ends open, and the lower end of shaft member is provided with close Capping.

As a kind of preferred version, in the deployed state, its one end width is big, and other end width is little for described electrode slice, its It is coated on the outer surface of shaft member.

As a kind of preferred version, described two electrode slices are respectively provided with contact, and the contact of two electrode slices is respectively positioned on shaft member The outer surface of end.

As a kind of preferred version, described electrode slice is Copper Foil or aluminium foil.

This utility model compared with prior art has clear advantage and beneficial effect, specifically, by above-mentioned technology Scheme understands:

By two electrode slice symmetry volumes being overlayed on the outer surface of shaft member, utilize shape between two electrode slices and the inwall of trocar sheath Becoming to have gap to constitute two electric capacity, when the difference maximum of two capacitances when, now liquid level is just at the 1/2 of whole sensor At liquid level；When the difference of two capacitances is minimum, simultaneously the when of two capacitances also minimum, now liquid level is just at whole sensor Minimum liquid level at；The capacitance of full position can be calculated according to this capacitance at two, can realize automatically calibrating；This practicality is new Type simple in construction, convenient for production, low cost, and the degree of accuracy calibrated is high, is worth of widely use.

For more clearly illustrating architectural feature of the present utility model and effect, it is right to come with specific embodiment below in conjunction with the accompanying drawings This utility model is described in detail.

Accompanying drawing explanation

Fig. 1 is the schematic cross-section of the preferred embodiment of this utility model；

Fig. 2 is the expansion schematic diagram of the preferred embodiment of this utility model；

Fig. 3 be this utility model preferred embodiment in the schematic perspective view that is arranged in shaft member of electrode；

Fig. 4 be this utility model preferred embodiment in electrode be arranged in shaft member another schematic perspective view；

Fig. 5 be this utility model preferred embodiment in the schematic diagram of difference and liquid level change of capacitance of C1 Yu C2.

Accompanying drawing identifier declaration:

10, trocar sheath 101, gap

20, shaft member 30, electrode slice

31, contact 40, sealing lid.

Detailed description of the invention

Refer to shown in Fig. 1 to Fig. 4, that show the concrete structure of the preferred embodiment of this utility model, include Trocar sheath 10, shaft member 20 and two electrode slices 30.

This shaft member 20 is arranged in trocar sheath 10, and the symmetrical volume of this two electrode slice 30 overlays on the outer surface of shaft member 20 and along shaft member 20 axially extending, be formed with gap 101 between two electrode slices 30 and the inwall of trocar sheath 10 and constitute two electric capacity.

In the present embodiment, described shaft member 20 is coaxially disposed with trocar sheath 10, and the two ends up and down of described trocar sheath 10 are the most spacious Opening, described shaft member 20 is hollow structure, its upper and lower both ends open, and the lower end of shaft member 20 is provided with sealing lid 40.

Under described electrode slice 30 deployed condition, its one end width is big, and other end width is little, and its concrete shape can be triangular in shape Or trapezoidal, not to be limited, and it is coated on the outer surface of shaft member 20, and, described two electrode slices 30 are respectively provided with contact 31, and two The contact 31 of electrode slice 30 is respectively positioned on the outer surface of the upper end of shaft member 20.And, described electrode slice 30 is Copper Foil or aluminium foil, certainly It can be also other conductive material, not to be limited.

During use, two electrode slices 30 form two electric capacity with trocar sheath 10, are respectively as follows: C1 and C2, along with the rising of liquid level, The difference of the capacitance of C1 Yu C2 is as it is shown in figure 5, when the difference maximum of C1 Yu C2 when, now liquid level is just in whole biography At 1/2 liquid level of sensor；When the difference of C1 Yu C2 is minimum, simultaneously the when of the value of C1 and C2 also minimum, now liquid level just exists At the minimum liquid level of whole sensor；Calculate the capacitance of full position according to this capacitance at two, capacitance liquid level can be realized Automatic calibration of sensor；Computing formula is as follows:

The capacitance C at 1/2 liquid level is calculated the difference maximum of C1 Yu C2 when_In=C1+C2。

When the difference of C1 Yu C2 is minimum, the when of the value of C1 and C2 also minimum, calculate the capacitance in room: C simultaneously_Empty=C1_Min +C2 _Min。

The capacitance C of full position_Full=(C_In-C_Empty)*2+C_Empty 。

Design focal point of the present utility model is: by two electrode slice symmetry volumes overlay on the outer surface of shaft member, utilize two It is formed with gap between electrode slice and the inwall of trocar sheath and constitutes two electric capacity, when the difference maximum of two capacitances when, this Time liquid level just at 1/2 liquid level of whole sensor；When the difference of two capacitances is minimum, when two capacitances are also minimum simultaneously Waiting, now liquid level is just at the minimum liquid level of whole sensor；The electric capacity of full position can be calculated according to this capacitance at two Value, can realize automatically calibrating；This utility model simple in construction, convenient for production, low cost, and the degree of accuracy calibrated is high, value Must promote the use of.

The above, be only preferred embodiment of the present utility model, not make technical scope of the present utility model Any restriction, thus every according to technical spirit of the present utility model, above example is made any trickle amendment, equivalent become Change and modify, all still falling within the range of technical solutions of the utility model.

Claims

1. the capacitive liquid level sensor that can automatically calibrate, it is characterised in that: include trocar sheath, shaft member and two electrodes Sheet；This shaft member is arranged in trocar sheath, and this two electrode slices symmetry volume overlays on outer surface axially extending along shaft member of shaft member, and two It is formed with gap between electrode slice and the inwall of trocar sheath and constitutes two electric capacity.

The capacitive liquid level sensor that can automatically calibrate the most according to claim 1, it is characterised in that: described shaft member and overcoat Pipe is coaxially disposed.

The capacitive liquid level sensor that can automatically calibrate the most according to claim 1, it is characterised in that: described trocar sheath upper Lower open at both ends.

The capacitive liquid level sensor that can automatically calibrate the most according to claim 1, it is characterised in that: described shaft member is hollow Structure, its upper and lower both ends open, the lower end of shaft member is provided with sealing lid.

The capacitive liquid level sensor that can automatically calibrate the most according to claim 1, it is characterised in that: described electrode slice is in exhibition Under open state, its one end width is big, and other end width is little, and it is coated on the outer surface of shaft member.

The capacitive liquid level sensor that can automatically calibrate the most according to claim 1, it is characterised in that: described two electrode slices are equal Having contact, the contact of two electrode slices is respectively positioned on the outer surface of the upper end of shaft member.

The capacitive liquid level sensor that can automatically calibrate the most according to claim 1, it is characterised in that: described electrode slice is copper Paper tinsel or aluminium foil.