Nano flow capacitive liquid level sensor and manufacturing method thereof

A liquid level sensor, capacitive technology, applied in the field of liquid level sensors

Active Publication Date: 2017-12-29
XI AN JIAOTONG UNIV
View PDF5 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to design a nano-liter capacitive liquid level sensor and its prep

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Nano flow capacitive liquid level sensor and manufacturing method thereof
  • Nano flow capacitive liquid level sensor and manufacturing method thereof
  • Nano flow capacitive liquid level sensor and manufacturing method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] Such as figure 1 Shown: a continuous nanoliter capacitive liquid level sensor based on MEMS technology, suitable for the bioreactor structure in the field of microfluidics, the liquid level sensor is installed on the outer surface of the bioreactor 1, and the bioreactor 1 is opened There are a container outlet 12 and a container inlet 9, the liquid in the bioreactor 1 enters the liquid level sensor through the container outlet 12, and then returns to the bioreactor 1 from the container inlet 9.

[0035] Such as figure 2 As shown, the capacitive liquid level sensor includes: PDMS layer 2 , Si structure layer 3 and glass layer 4 . Among them, the function of PDMS layer 2 is to encapsulate the sensor on the outer surface of the bioreactor. Of course, other materials can be used in addition to PDMS, as long as the sensor can be encapsulated on the outer surface of the bioreactor. In order to communicate with the interior of the bioreactor, the PDMS layer is provided with...

Embodiment 2

[0043] Such as Figure 8 As shown, the difference between this embodiment and one of the specific embodiments is that: the horizontal gaps 19 are equidistantly arranged between the serpentine inner surface gaps, and the oxidation insulation treatment is done; the other is the same as the one of the specific embodiments. This embodiment can accurately monitor individual sensitive liquid level points on the basis of continuous liquid level measurement. When the liquid level reaches the transverse gap, the capacitance change of the system is obviously higher than usual, which is very beneficial for occasions that are sensitive to liquid level and volume transmission.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Sensitivityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a capacitive liquid level sensor and a manufacturing method thereof. The liquid level sensor comprises a surface PDMS layer, a Si structure layer and a bottom glass layer, wherein the Si structure layer and electrodes are obtained through a process combining DRIE dry etching and wet etching; a closed liquid cavity is formed through ion bonding and the PDMS layer, and the change of electrolyte between capacitance polar plates is caused by the change of the liquid level, so that the electric charge between the capacitance polar plates is changed; the change of the liquid level between the polar plates can be detected through a peripheral circuit. Due to the fact that the distances are equal everywhere, the volume of the liquid between the polar plates can be calculated accurately and directly; the second embodiment of invention can achieve accurate monitoring of the characteristic liquid level, and overall continuous observation can be achieved. The liquid sensor has the advantages of being sensitive in reaction, low in manufacturing cost, high in precision and the like.

Description

【Technical field】 [0001] The invention relates to the technical field of liquid level sensors, in particular to a high-precision continuous capacitive liquid level sensor based on MEMS technology. 【Background technique】 [0002] In the industrial field, in order to realize automatic production and measurement, precise measurement of liquid level is required. [0003] Liquid level measurement includes liquid level annunciator and continuous liquid level measurement. The former mainly monitors and warns several fixed liquid level positions, while the latter requires continuous liquid level measurement in the full range, and is widely used in petrochemical, biopharmaceutical micro-flow control and other fields. [0004] At present, there are more than 20 methods used in continuous liquid level measurement, such as float method, laser interferometry, magnetostrictive method, etc. In practical applications, it is necessary to select a suitable measurement method according to cer...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01F23/26
CPCG01F23/263
Inventor 韦学勇张宏才王威威蒋庄德
Owner XI AN JIAOTONG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap