CN206638366U - A kind of high-precision quartz crystal temperature effect meter - Google Patents

Abstract

The utility model provides a kind of high-precision quartz crystal temperature effect meter, including：Sensor, cable and main frame, the output end of the sensor and the input of the main frame pass through cable connection, wherein described sensor is quartz crystal sensor, for sensing temperature, the frequency signal of the sensor is used for recording frequency number and then data acquisition by the cable transmission to the main frame, the main frame.High-precision quartz crystal temperature effect meter of the present utility model, using equally accurate frequency collection mode, realize gamut resolving power up to 0.000001 DEG C；Using isolation power supply mode, general safety performance of the present utility model is improved so that frequency signal transmission over long distances is possibly realized；Using single band shielded cable, protection signal is not by external interference.

Description

A kind of high-precision quartz crystal temperature effect meter

Technical field

The utility model belongs to long range, high-resolution hydrocode field, more particularly to a kind of high-precision quartz crystal temperature Degree meter.

Background technology

It can all be related to the real-time monitored to temperature physical quantity in industries such as earthquake, water conservancy, environmental protection；Particularly Seismic Travelling Industry, the seizure for information of earthquake, verified by many scholars, (tens to hundreds of meters of distances under earth's surface) temperature in the earth's crust Anomalous variation, for Earthquake Prediction Research explore work provide very valuable data.

The relatively long distance temperature observation of special industry, if having two technical bottlenecks using traditional observation procedure：First, It is required that high accuracy, as seismic industry requires its resolving power of temperature observation up to 0.0001 DEG C；Secondly require that the relatively long distance of signal is defeated Send；And realize that the premise that these specialties measure is measuring system, particularly the stabilization of temperature sensor, the long-time of safety connect Continuous work.The RTD formula temperature survey electric bridge in laboratory, its resolving power and stability are attained by requirements, but it is to observation ring Border, measurement cable distance have strict demand；Bridge-type temperature measurement circuit is directly applied to field observation and occurs that signal attenuation is asked Topic；And measurement and signal acquisition circuit are all arranged at sensor internal, it is difficult to avoid because circuit self-heating causes to count again The problem of according to interference, and how to ensure the continuous and steady operation problem of complicated circuit in sensor.

The mid-1970s, U.S. HP have succeeded in developing quartz crystal thermometer, and resolution ratio reaches 0.0001 DEG C of even more high, but its Only 3.7 meters of probe cable, is suitable only for laboratory work, it is impossible to be used in long range field observation.Because quartz crystal temperature passes Sensor output quantity is frequency quantity, and by being suitably modified, its resolving power can reach 0.0001 DEG C even more by modern frequency splitting technology Height, and signal output, in the case where power is certain, the signal attenuation of long range does not influence measurement accuracy, will not cause thermometric portion Spontaneous heating of part etc..But for such temperature observation, if using traditional powering mode, i.e., the operation that can reduce sensor is pacified Quan Xing, particularly easily destroyed by thunderbolt；Other temperature measurement circuit is generated heat with the increase of signal transmission distance, and the system brought is missed Difference.

It is, therefore, desirable to provide a kind of long range, high security, high-precision quartz crystal thermometer.

Utility model content

The purpose of this utility model, mainly solves safety of traditional power supply mode for underground long range temperature sensor Property, accuracy it is more difficult and meanwhile ensure problem, for some industries deep-well high-resolution hydrocode provide one it is safe and reliable Design.

High-precision quartz crystal temperature effect meter of the present utility model, including：Sensor, cable and main frame, the sensor Output end and the main frame input by cable connection, wherein the sensor be Quartz Temperature Sensor, use In sensing temperature, by the cable transmission to the main frame, the main frame is used to record frequency the frequency signal of the sensor Rate signal and then data acquisition.The main frame includes power supply isolation module, for being powered to the sensor using isolation Mode.

Preferably, the isolation power supply mode is that sensor power supply ground wire is separated by with other ground wires in the main frame From.

Preferably, the cable is single with shielded cable, including cable core and shielding line.

Preferably, the cable core is used for the power supply of sensor, is also used for the transmission of frequency signal, and the shielding line is used to protect The frequency signal of sensor output is protected not by external interference.

Preferably, the stimulus part of the main frame is according to electromagnetic induction principle, by transformer by the sensor Frequency signal carries out isolation transmission.

Preferably, the main frame includes signal acquisition module, and the signal acquisition module uses equally accurate frequency collection side Formula.

The utility model has following advantages：

1st, high-precision quartz crystal temperature effect meter of the present utility model uses equally accurate frequency collection mode, and gamut can be achieved Resolving power is up to 0.000001 DEG C；

2nd, the utility model makes sensor power supply ground wire be isolated with other ground wires in main frame using power supply mode is isolated, The effect of sensor lightning-protection is realized, improves the general safety performance of the utility model high-precision quartz crystal temperature effect meter；Simultaneously According to electromagnetic induction principle, frequency information is conveyed directly to host machine part by transformer coil and carries out shaping by the utility model With amplification so that the integrality of frequency signal is unrelated with voltage attenuation, and this is for over long distances, particularly deep-well temperature observation comes Say that there is practical value；

3rd, sensor described in the utility model only needs two transmission lines to complete power supply and signal transmission, the utility model The cable is using single band shielded cable so that screen layer is not only when ground wire but also protection signal is not by external interference.When being grown During distance signal transmission, cable core can be replaced directly with steel wire, both met the requirement of power supply and signal transmission, can have been improved electricity again The intensity of cable.

Brief description of the drawings

Fig. 1 is the structural representation of the utility model quartz crystal thermometer；

Fig. 2 is the structural representation of cable of the present utility model；

The structural representation of Fig. 3 main frames of the present utility model；

Fig. 4 is the sensor isolation electrical schematic of main frame of the present utility model；

Fig. 5 is the sensor signal return of main frame of the present utility model, the schematic diagram of shaping and amplification.

Fig. 6 is the schematic diagram that signal acquisition module of the present utility model carries out signal acquisition by equally accurate frequency measuring method.

Embodiment

Below by embodiment, the utility model is described in further detail, and its purpose, which is only that, more fully understands that this practicality is new The research contents of type and unrestricted the scope of protection of the utility model.

As shown in figure 1, high-precision quartz crystal temperature effect meter of the present utility model is mainly by sensor 1, cable 2 and main frame 3 Three parts form.

The quartz-crystal resonator of sensor 1 is made of the planoconvex spotlight quartz crystal block of LC cut types, its diameter approximate number Millimeter, convex radius is about more than 100 millimeters.Quartz-crystal resonator is packaged in the shell for filling helium, in sensing electricity The characteristic varied with temperature in road using its piezo-electric effect and eigentone forms temperature-sensitive oscillator.High-precision quartz is brilliant Thermometer body can obtain the relation (quartz between quartz-crystal resonance frequency and quartz crystal temperature by modern frequency splitting technology The frequency signal of crystal temperature effect sensor output need to only reach 0.1Hz, you can realize temperature resolving power up to 0.0001 DEG C, i.e. frequency It it is 1KHz/ DEG C with vs. temperature).

Cable 2 uses single shielded cable, including cable core 21 and shielding line 23.The output of sensor 1 is frequency signal, even if Signal produces a certain degree of decay during being transmitted by cable 2, does not also interfere with the integrality of host signal collection. When carrying out long distance signal transmission (such as：Measurement distance>600m), the cable core of cable 2 can be replaced directly with steel wire, and this is not only full Foot power supply and the transmission demand of signal, while the intensity of cable can be improved again.As shown in Fig. 2 cable 2 is from inside to outside by for cable core 21, insulating barrier 22, shielding line (mesh shields layer) 23 and plastic envelope 24 are formed.The shielding line 23 of cable 2 makees ground wire, cable core 21 (center copper cash or steel wires) had both made sensor supply lines, made the transmission line of sensor signal again.

As shown in figure 3, main frame 3 includes power supply 31, power supply isolation module 32, Signal-regulated kinase 33, signal acquisition module 34th, data memory module 35, communication module 36 and data disaply moudle 37.Wherein, power module 31 is used to enter other modules Row power supply.

By isolating power supply module 32, power supply ground wire of the main frame 3 to sensor 1 using isolation power supply mode, i.e. sensor 1 Isolate (with reference to figure 4) with the other circuit part ground wires of instrument.Power supply (VCC and VEE) is by isolating power supply DC/DC modules 32 (T1) 9V voltages, are exported, and ground wire (pin 4) is isolated, and directly powers (PROB+ and PROB-) to sensor by socket J11, And power supply state is shown using photoisolator (U4) connection LED, make in the ground wire and circuit board of sensor power supply otherly Line isolation avoids the effect of thunderbolt to reach.Seismic industry carries out the interior constant depth that drills using high-precision quartz crystal temperature effect meter The Continuous Observation of water temperature (ground temperature) etc., the cable length used are usually 200-1000m, but the well head set of observation site internal drilling Pipe resistance to earth much smaller than the grounding resistance for providing ground wire in sight chamber for main frame, so underground equipment typically compared with uphole equipment more Easily damaged by thunder and lightning, but after use isolation power supply, lightning protection effect is obvious, also rare to have well even if uphole equipment is by broken by lightning The phenomenon that lower sensor is struck by lightning.

As shown in figure 5, the primary coil string for passing through isolating transformer of powering (T2) for the 9V isolation voltages that sensor provides The feeder ear of sensor 1 is linked to, the 9V direct currents of isolation supply sensor 1 by transformer (T2).In current supply circuit, due to Quartz-crystal resonator in sensor 1 is excited by electric current, produces a certain degree of concussion, will after sensor circuit is nursed one's health AC signal is superimposed upon in the direct current of power supply.According to electromagnetic induction principle, the AC signal being superimposed upon in direct current can become Depressor (T2) end is transferred to secondary coil from primary coil, so as to realize sensor 1 to the effect of the signal-isolated transmission of main frame 3 Fruit.The sensor signal sensed in transformer secondary coil is delivered in the shaping and amplifying circuit of main frame 3 again, signal passes through After shaping, the operational amplifier INA128 of amplifying circuit input is input to, signal is amplified, the output letter after amplification Number be 5V square-wave signal, you can be input to signal acquisition module 34.Wherein, the shaping in Fig. 5 and amplifying circuit are i.e. corresponding Signal-regulated kinase 33 in Fig. 3.Other modules such as data memory module 35, the communication module that other the application is not discussed in detail 36 and the grade of data disaply moudle 37 be conventional modules.

Signal acquisition module 34 realizes its function using equally accurate Technology of Frequency Measurement by Using.Frequency collection is record unit time internal moment The rising edge of shape ripple or the number of trailing edge, therefore the smallest record unit of universal frequency collection method is 1Hz.This practicality is new The signal acquisition module 34 of main frame 3 described in type uses equally accurate frequency measuring method, frequency that can really in record unit time Rate, mainly it is realized by the following method：

As shown in fig. 6, standard-frequency signal fo is used as using the accurate high-frequency signal of frequency (clock signal).First, in advance It is Ts to put gate time so that the gate time of measurement is the integral multiple of tested time.Then, according to the frequency of measured signal (by measured frequency) fx synchronizes to preset gate time, obtains sync gate time Ts '.Then, it is same within gate time When standard signal pulse fo and measured signal pulse fx are counted.In Fig. 6, Nx is the number of measured signal, and Tx is quilt The cycle of signal is surveyed, according to Ts '=Nx*Tx, the number of measured signal can be obtained.No is clock signal number, and To believes for clock Number cycle, according to Ts '=No*To, clock signal number can be obtained.Measured signal pulse fx is entered by standard signal pulse fo Row refinement, can obtain higher frequency resolution.That is, common frequency collection method only records fo calibration pulse Number, but last pulse signal can not be recorded intactly at the end of gate time, so as to produce rounding error； And equally accurate frequency collection is recorded, so as to obtain better than 1Hz's by the fx of higher frequency to last endless whole pulse Frequency accuracy, the precision depend on fx frequency accuracy.In the utility model, gathered by equally accurate, 0.01Hz can be obtained The frequency resolution of even more high, and then pass through the corresponding relation of temperature and frequency so that temperature resolving power is up to 0.000001 ℃。

Obviously, those of ordinary skill in the art is it should be appreciated that the embodiment of the above is intended merely to explanation originally Utility model, and being not used as to restriction of the present utility model, if in spirit of the present utility model, to Change, the modification of the upper embodiment will all fall in Claims scope of the present utility model.

Claims (6)

1. A kind of 1. high-precision quartz crystal temperature effect meter, it is characterised in that including：Sensor, cable and main frame, the sensor Output end and the main frame input by the cable connection, wherein：

   The sensor is Quartz Temperature Sensor, for sensing temperature, the frequency signal transmission of the sensor to institute State main frame；

   The cable is used for the frequency signal transmission to the main frame；

   The main frame is used for according to the frequency signal data acquisition,

   The main frame include power supply isolation module, for the sensor using isolation power supply by the way of.
2. 2. high-precision quartz crystal temperature effect meter according to claim 1, it is characterised in that the isolation power supply mode is institute Sensor power supply ground wire is stated to be isolated with other ground wires in the main frame.
3. 3. high-precision quartz crystal temperature effect meter according to claim 1, it is characterised in that the cable shields for single band Cable, including cable core and shielding line.
4. 4. high-precision quartz crystal temperature effect meter according to claim 3, it is characterised in that the cable core is used for sensor Power supply, the transmission of frequency signal is also used for, the frequency signal that the shielding line is used to protect sensor to export is not by external interference.
5. 5. high-precision quartz crystal temperature effect meter according to claim 1, it is characterised in that the power supply isolation mode of the main frame Block includes transformer, and the sensor frequency signal is carried out into isolation transmission by transformer according to electromagnetic induction principle.
6. 6. high-precision quartz crystal temperature effect meter according to claim 1, it is characterised in that the main frame includes signal acquisition Module, the signal acquisition module use equally accurate frequency collection mode.