CN203164151U

CN203164151U - Methane sensor

Info

Publication number: CN203164151U
Application number: CN 201320210120
Authority: CN
Inventors: 宋亚东
Original assignee: SHANDONG SANDA BOAN MEASUREMENT CONTROL TECHNOLOGY Co Ltd
Current assignee: SHANDONG SANDA BOAN MEASUREMENT CONTROL TECHNOLOGY Co Ltd
Priority date: 2013-04-24
Filing date: 2013-04-24
Publication date: 2013-08-28
Anticipated expiration: 2023-04-24

Abstract

The utility model relates to a low-concentration methane sensor capable of continuously measuring the concentration of 0.00 percent to 4.00 percent of methane gas. The methane sensor provided by the utility model comprises a single chip microcomputer circuit mainboard, a power supply converting module, a Wheatstone bridge and an audible and visual alarm, wherein the single chip microcomputer circuit mainboard is a 3.3V low-voltage power supply single chip microcomputer, an automatic resetting EEPROM (electrically erasable programmable read-only memory), a sampling circuit and a display circuit are arranged on the single chip microcomputer circuit mainboard, the Wheatstone bridge consists of a carrier catalysis element, a resistor and a digital adjustable potentiometer, and the carrier catalysis element consists of a black element and a white element in mutual series connection. The methane sensor belongs to the low-concentration methane sensor capable of continuously measuring the concentration of 0.00 percent to 4.00 percent of methane gas accurately and reliably.

Description

Methane transducer

Technical field

The utility model relates to a kind of sensor, especially relates to a kind of low-concentration methane sensor of concentration of methane gas that can continuous coverage 0.00%～4.00%.

Background technology

Along with continuous expansion and the extension of mine underground mining scope, subsurface environment also becomes and becomes increasingly complex, and to subsurface environment, especially the requirement of air is more and more higher.Ventilation is carried out in the down-hole, and is pure and fresh to guarantee underground air, satisfies staff's eupnea and the gathering of minimizing harmful gas and also becomes more and more important.At present, the traditional methane transducer that is used for explosive gas atmosphere under the coal mine is subjected to factor affecting such as transmission medium, environment electromagnetics interference easily, thereby makes methane concentration Monitoring Data bad student error.

Summary of the invention

The utility model is in order to solve the problem that prior art exists, and a kind of low-concentration methane sensor of concentration of methane gas that can continuous coverage 0.00%～4.00% is provided.

Methane transducer of the present utility model is characterized in that: comprise single chip circuit mainboard, power transfer module, Wheatstone bridge, audible-visual annunciator; Described single chip circuit mainboard is 3.3V low voltage power supply single-chip microcomputer, and described single chip circuit mainboard is provided with the EEPROM that automatically resets, sample circuit and display circuit, and described Wheatstone bridge is made up of carrier catalyst element and resistance and digital adjustable potentiometer.Described carrier catalyst element is made up of black element and the white element of mutual series connection.Described sample circuit is 10 bits serial A/D converter TLV1549, and described single chip circuit mainboard is 3.3V low voltage power supply single chip computer AT 89LV52.

Methane transducer of the present utility model, adopt 3.3V low voltage power supply single chip computer AT 89LV52, it has function and consumes plurality of advantages such as low and possibility height, sensor detects principle and adopts thermocatalysis principle, the specific implementation process is by forming Wheatstone bridge by carrier catalyst element and resistance and digital adjustable potentiometer, when the methane in the environment enters air chamber with diffusion way, react with carrier catalyst element, the electric signal that Wheatstone bridge output is corresponding with methane concentration, this electric signal is after A/D converter transforms, deliver to single-chip microcomputer and carry out the data processing, finish demonstration, the alarm lamp function.The low-concentration methane sensor of the concentration of methane gas that methane transducer of the present utility model can be accurately and reliably, can continuous coverage 0.00%～4.00%.

This shows that the utility model relatively has outstanding substantive distinguishing features with prior art and improves significantly.

Description of drawings

Fig. 1 is the structural representation of methane transducer of the present utility model.

Fig. 2 is the synoptic diagram of Wheatstone bridge shown in Figure 1.

Embodiment

By accompanying drawing 1 and Fig. 2 as can be known: methane transducer of the present utility model comprises single chip circuit mainboard, power transfer module, Wheatstone bridge, audible-visual annunciator; Described single chip circuit mainboard is 3.3V low voltage power supply single-chip microcomputer, and described single chip circuit mainboard is provided with the EEPROM that automatically resets, sample circuit and display circuit, and described Wheatstone bridge is made up of carrier catalyst element and resistance and digital adjustable potentiometer.Described carrier catalyst element is made up of black element and the white element of mutual series connection.Described sample circuit is 10 bits serial A/D converter TLV1549, and described single chip circuit mainboard is 3.3V low voltage power supply single chip computer AT 89LV52.

Methane transducer of the present utility model, adopt 3.3V low voltage power supply single chip computer AT 89LV52, it has function and consumes plurality of advantages such as low and possibility height, sensor detects principle and adopts thermocatalysis principle, the specific implementation process is by forming Wheatstone bridge by carrier catalyst element and resistance and digital adjustable potentiometer, when the methane in the environment enters air chamber with diffusion way, react with carrier catalyst element, the electric signal that Wheatstone bridge output is corresponding with methane concentration, this electric signal is after A/D converter transforms, deliver to single-chip microcomputer and carry out the data processing, finish demonstration, the alarm lamp function.

Sample circuit adopts 10 bits serial A/D converter TLV1549, realizes with the voltage that Wheatstone bridge changes, being converted into the digital signal of variation when methane concentration changes, and exports to CPU.

Display circuit adopts 4 LED numerals to show, shows measurement value sensor.The information of checking the digital regulation resistance of sensor by the infrared remote control receiving circuit on the mainboard or the button on the mainboard.

Sound and light alarm and control signal output circuit, when the methane concentration that measures reaches alarm set point, hummer and luminotron produce sound and light alarm, when the methane concentration that measures arrives the outage point, also export outage control signal (5mA current signal) simultaneously except sound and light alarm.

Power transfer module adopts the design of high efficiency switching power circuit, have wide input voltage range (9～24VDC), characteristics such as output voltage precision height.Module adopts ceramic dosing technology, has characteristics such as high temperature resistant, moistureproof, waterproof.

Carrier catalyst element is made up of black-and-white component, and the black-and-white component series connection is as an arm of Wheatstone bridge, and resistance constitutes another arm of Wheatstone bridge.The Wheatstone bridge two ends add stable voltage U (3V), when the air that contains methane under the effect of high temperature and platinum black catalyst, flameless burning takes place, on white element, then do not make methyl hydride combustion, thereby the temperature that makes black element is than white element height.Platinum filament in the black element be heating element be again the thermal sensing element of temperature sensor.According to the characteristic of the positive temperature coefficient (PTC) of platinum filament, resistance was big when temperature was high, and the voltage drop on the black element increases, and the Wheatstone bridge out of trim changes output voltage.

Claims

1. a methane transducer is characterized in that: comprise single chip circuit mainboard, power transfer module, Wheatstone bridge, audible-visual annunciator; Described single chip circuit mainboard is 3.3V low voltage power supply single-chip microcomputer, and described single chip circuit mainboard is provided with the EEPROM that automatically resets, sample circuit and display circuit, and described Wheatstone bridge is made up of carrier catalyst element and resistance and digital adjustable potentiometer.

2. methane transducer according to claim 1 is characterized in that: described carrier catalyst element is made up of black element and the white element of mutual series connection.

3. according to claim 1 or 2 described methane transducers, it is characterized in that: described sample circuit is 10 bits serial A/D converter TLV1549, and described single chip circuit mainboard is 3.3V low voltage power supply single chip computer AT 89LV52.