CN203882485U - Experimental device for designing resistance thermometer by employing non-balanced bridge - Google Patents
Experimental device for designing resistance thermometer by employing non-balanced bridge Download PDFInfo
- Publication number
- CN203882485U CN203882485U CN201420309352.0U CN201420309352U CN203882485U CN 203882485 U CN203882485 U CN 203882485U CN 201420309352 U CN201420309352 U CN 201420309352U CN 203882485 U CN203882485 U CN 203882485U
- Authority
- CN
- China
- Prior art keywords
- bridge
- temperature
- resistance
- adjustable
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Abstract
The utility model discloses an experimental device for designing a resistance thermometer by employing a non-balanced bridge. A bridge is formed by a bridge-arm-adjustable resistor R1, a bridge-arm-adjustable resistor R2, a bridge-arm-adjustable resistor R3 and a thermal-sensitive resistor Rt. An adjustable voltage source is used for supplying power to the bridge. The thermal-sensitive resistor is placed in a glass water tank. A semiconductor refrigerating device, a heating device and a temperature sensor are disposed in the water tank. An output voltage of the bridge is amplified through an operational amplifier and is displayed by a digital voltmeter. The experimental device is operated by following steps: adjusting the bridge-arm-adjustable resistors into appropriate values, setting a temperature of a heat-transferring liquid as t through a temperature controller, reading an output voltage U0(t) of the bridge, carrying out the measurement process at an interval of a certain temperature and drawing a U0(t)-t curve to obtain the temperature t through the U0(t). According to the utility model, the bridge-arm-adjustable resistors are used as bridge arms of the non-balanced bridge so that sensitivity of the thermometer can be increased. A measurement range of the designed thermometer can be expanded to below a room temperature. An output voltage of the bridge is convenient to adjust. A value displayed by the designed thermometer is easy to be just a centigrade temperature value of a to-be-tested subject.
Description
Technical field
The utility model relates to a kind of physics facility, specifically relates to a kind of experimental provision that utilizes nonequilibrium bridge design resistance thermometer.
Background technology
The measurement of temperature be controlled at we daily life and production, scientific research in be widely used, for example, fire alarm annunciator, constant temperature oven, refrigerator etc.In these application apparatus, be usually that electric signal is gone to control topworks's work by " processing " later.But in " processing " before, first the temperature signal being provided by controlled system must be converted to corresponding electric signal, temperature sensor is exactly the device of carrying out this task.Semiconductor thermistor is the sensitive element of a kind of resistance with temperature change generation marked change, in operating temperature range, what resistance increased with temperature rising is called positive temperature coefficient (PTC) (Positive Temperature Coefficient is called for short PTC) thermistor, otherwise is called negative temperature coefficient (Negative Temperature Coefficient is called for short NTC) thermistor.Thermistor have volume little, react the advantage such as fast, easy to use, by thermistor, the variation that temperature and variation thereof can be converted to electrical quantities or electrical quantities is measured.So it is widely used in the temperature survey and control work of the every field such as work, agriculture, doctor, traffic, military affairs, scientific research.
Direct current bridge is a kind of electricity measuring Instrument of precision, can be divided into balanced bridge and nonequilibrium bridge two classes.Balanced bridge is by regulating bridge balance, testing resistance and measuring resistance being compared to the size that obtains testing resistance, if Huygens's electric bridge, Kelvin bridge etc. are all balanced type direct current electric bridges.Due to needs adjustment, therefore balanced bridge can only be used for measuring the physical quantity with metastable state.Along with the development of measuring technique, the application of electric bridge is no longer confined to the scope of balanced bridge, and nonequilibrium bridge is used widely in the measurement of non electrical quantity.In Practical Project and scientific experiment, continually varying often to be measured, as long as can connect the variation of same resistance value to be measured, just can adopt nonequilibrium bridge to measure.By various resistance type sensor access bridge circuits, the output voltage on bridge road just can reflect the subtle change of arm resistance, therefore, just can detect variation to be measured, as temperature, pressure, humidity etc. by the output voltage of measuring nonequilibrium bridge.
Utilizing the experiment of nonequilibrium bridge design resistance thermometer is a common experimental project in Physical Experiment, and it is a more typical nonequilibrium bridge application example, is the blank of all kinds of digital thermometers on market, has certain practical value.
Utilize at present the experimental provision of nonequilibrium bridge design resistance thermometer mainly to have the following disadvantages:
One, the general single-deck rheostat that adopts fixing stepping amount, certain gear of brachium pontis of nonequilibrium bridge, resistance adjustable extent is smaller, in a lot of situations, can not adapt with thermistor, makes the thermometer remolding sensitivity of design lower, affects experiment effect.
Its two, heating source temperature controller is generally power supply heating, fan cooled, using air as heat transfer substance, to be heated inhomogeneous, measurement range can only be generally room temperature or higher than room temperature, cannot study the situation lower than room temperature, the thermometer measure scope of design is restricted.
Its three, bridge output voltage size is difficult for regulating, being difficult to make numerical value that the thermometer of design shows is just in time the celsius temperature scale of object under test.
Utility model content
In order to overcome the above-mentioned deficiency of prior art, the utility model proposes a kind of experimental provision that utilizes nonequilibrium bridge design resistance thermometer, this device adopts the brachium pontis of adjustable arm resistance as nonequilibrium bridge, resistance adjustable extent is large, can match with all kinds of thermistors, thus the sensitivity that improves design temperature meter.Using liquid as heat transfer substance, be heated evenly, and the thermometer measure scope of design can extend to below room temperature.Bridge output voltage size adjustment is convenient, and easily making the numerical value that the thermometer of design shows is just in time the celsius temperature scale of object under test.
The utility model solves the technical scheme that its technical matters adopts: by adjustable arm resistance R
1, R
2, R
3and semiconductor thermistor or metal thermo-sensitive resistance R
tas four brachium pontis of electric bridge, form an electric bridge respectively, provide power supply by variable voltage source to electric bridge, the size of voltage source output voltage can regulate by knob, and can on voltage source voltage display screen, show.Semiconductor thermistor or metal thermo-sensitive resistance are placed in the glass flume of one end sealing, and bath of glass cell wall adopts double-decker, and centre is evacuated, to play good heat insulation effect.In heat transfer liquids implantation glass tank, highly suitable, in glass flume, in heat transfer liquids, top part arranges semiconductor refrigerating plant, be used for Cooling Heat Transfer liquid, part arranges a heating arrangement on the lower, be used for heating heat transfer liquids, center section arranges a temperature sensor, be used for measuring the temperature of heat transfer liquids, semiconductor cooling device, heating arrangement and temperature sensor are connected with temperature controller by interface respectively, can set the temperature of heat transfer liquids by the button on temperature controller.By the temperature of pressing key assignments heat transfer liquids on temperature controller, utilize the actual temperature of temperature sensor measurement heat transfer liquids, temperature controller inside is controlled by microprocessor, if design temperature is lower than actual temperature, start semiconductor cooling device, Cooling Heat Transfer liquid, until temperature is reduced to setting value; If design temperature, higher than actual temperature, starts heating arrangement, heating heat transfer liquids, until temperature is increased to setting value.The output terminal concatenation operation amplifier one of electric bridge, as a reverse voltage amplifier, voltage amplification factor can be by changing adjustable feedback resistance R
fand adjustable input resistance R
isize regulate, the output voltage of electric bridge is amplified, then exports through the operational amplifier two as output buffer, on the voltage display screen of digital voltmeter, show.When experimental implementation, the first resistance in temperature-measuring range according to semiconductor thermistor or metal thermo-sensitive resistance, by adjustable arm resistance R
1, R
2and R
3size adjustment suitable, then by the temperature t of pressing key assignments heat transfer liquids on temperature controller, it is the temperature of semiconductor thermistor or metal thermo-sensitive resistance, it is suitable that the voltage amplification factor of operational amplifier one is regulated, and finally reads the output voltage U of electric bridge by the voltage display screen of digital voltmeter
o(t), measure once every uniform temperature, be recorded in table, and draw U
o(t)～t curve, so just can pass through U
o(t) measure temperature t.By suitably choosing arm resistance, adjustable feedback resistance R
fand adjustable input resistance R
ivalue, can make the magnitude of voltage that the voltage display screen of digital voltmeter shows is just in time the celsius temperature scale of object under test.
The beneficial effects of the utility model are, the resistance thermometer measurement range of this experimental provision design can extend to below room temperature, adopt the brachium pontis of adjustable arm resistance as nonequilibrium bridge, can match with all kinds of thermistors, thereby can improve the sensitivity of design temperature meter, bridge output voltage size adjustment is convenient, and easily making the numerical value that the thermometer of design shows is just in time the celsius temperature scale of object under test.
Brief description of the drawings
Below in conjunction with drawings and Examples, the utility model is further illustrated.
Accompanying drawing is structural representation of the present utility model.
1. adjustable arm resistance R in figure
1, 2. adjustable arm resistance R
2, 3. adjustable arm resistance R
3, 4. semiconductor thermistor or metal thermo-sensitive resistance R
t, 5. variable voltage source, 6. voltage source voltage display screen, 7. adjustable voltage source output terminal interface, 8. variable voltage source power switch, 9. variable voltage source voltage swing adjusting knob, 10. heating arrangement, 11. temperature sensors, 12. semiconductor cooling devices, interface between 13. heating arrangements and temperature controller, interface between 14. temperature sensors and temperature controller, interface between 15. semiconductor cooling devices and temperature controller, 16. temperature displays, 17. temperature controllers, 18. digital selection keys, 19. raise button, 20. lower button, 21. pilot lamp, 22. reset keys, 23. Temperature Setting buttons, 24. adjustable feedback resistance R
f, 25. adjustable input resistance R
i, 26. operational amplifier one, 27. operational amplifier two, 28. digital voltmeter input end interface, 29. digital voltmeters, 30. digital voltmeter voltage display screens, 31. digital voltmeter power switches, 32. digital voltmeter range gear adjusting knobs, 33,34. common ground ends, 35. glass flumes.
Embodiment
In accompanying drawing, by adjustable arm resistance R
11, adjustable arm resistance R
22, adjustable arm resistance R
33 and semiconductor thermistor or metal thermo-sensitive resistance R
t4 respectively as four brachium pontis of electric bridge, form an electric bridge, provide power supply by adjustable voltage source output terminal interface 7 to electric bridge by variable voltage source 5, the size of voltage source output voltage can regulate by variable voltage source voltage swing adjusting knob 9, and can on voltage source voltage display screen 6, show.Semiconductor thermistor or metal thermo-sensitive resistance R
t4 are placed in the glass flume 35 of one end sealing, and bath of glass cell wall adopts double-decker, and centre is evacuated, to play good heat insulation effect.In heat transfer liquids implantation glass tank 35, highly suitable, in the interior heat transfer liquids of glass flume 35, top part arranges semiconductor refrigerating plant 12, be used for Cooling Heat Transfer liquid, part arranges a heating arrangement 10 on the lower, be used for heating heat transfer liquids, center section arranges a temperature sensor 11, be used for measuring the temperature of heat transfer liquids, semiconductor cooling device 12, heating arrangement 10 and temperature sensor 11 are respectively by the interface 15 between semiconductor cooling device and temperature controller, interface 14 between interface 13 and temperature sensor and temperature controller between heating arrangement and temperature controller is connected with temperature controller 17.By the Temperature Setting button 23 on temperature controller 17, digital selection key 18, raises button 19, lowers button 20, can set the temperature of heat transfer liquids, and can on temperature display 16, show.Pilot lamp 21 is used to refer to heat transfer liquids temperature and whether reaches design temperature, and heat transfer liquids temperature is not equal to design temperature, and pilot lamp 21 is shown as red light, and heat transfer liquids temperature reaches design temperature, and pilot lamp 21 is shown as green light.The output terminal concatenation operation amplifier 1 of electric bridge, as a reverse voltage amplifier, voltage amplification factor can be by changing adjustable feedback resistance R
f24 and adjustable input resistance R
i25 size regulates, and the output voltage of electric bridge is amplified, then through operational amplifier 2 27 outputs as output buffer, on the digital voltmeter voltage display screen 30 of digital voltmeter 29, show.The range of digital voltmeter 29 can regulate by digital voltmeter range gear adjusting knob 32.
Specific experiment operation steps is:
(1) according to accompanying drawing connection line, according to semiconductor thermistor or metal thermo-sensitive resistance R
t4 resistances in temperature-measuring range, by adjustable arm resistance R
11, adjustable arm resistance R
22 and adjustable arm resistance R
33 size adjustment is suitable.
(2), by the Temperature Setting button 23 on temperature controller 17, digital selection key 18, raises button 19, lowers button 20, sets the temperature t of heat transfer liquids, i.e. semiconductor thermistor or metal thermo-sensitive resistance R
t4 temperature, until pilot lamp 21 becomes green light from red light, heat transfer liquids temperature reaches setting value.
(3) by changing adjustable feedback resistance R
f24 and adjustable input resistance R
iit is suitable that the voltage amplification factor of large young pathbreaker's operational amplifier 1 of 25 regulates, and it is suitable by digital voltmeter range gear adjusting knob 32, the range of digital voltmeter 29 to be regulated.Read the output voltage U of electric bridge by digital voltmeter voltage display screen 30
o(t), measure once every uniform temperature, by data recording in table in.
(4) draw U
o(t)～t curve, so just can pass through U
o(t) temperature t of measurement object under test.
(5) by suitably choosing adjustable arm resistance R
11, adjustable arm resistance R
22, adjustable arm resistance R
33, adjustable feedback resistance R
f24 and adjustable input resistance R
i25 value, can make the magnitude of voltage that digital voltmeter voltage display screen 30 shows is just in time the celsius temperature scale of object under test.
Above structure of the present utility model is set forth, but the not conditional intention of the embodiment that the utility model is introduced, and not deviating from the scope of the utility model purport, the utility model can have multiple variation and amendment.
Claims (2)
1. utilize an experimental provision for nonequilibrium bridge design resistance thermometer, specifically by adjustable arm resistance R
1, R
2, R
3and semiconductor thermistor or metal thermo-sensitive resistance R
trespectively as four brachium pontis of electric bridge, form an electric bridge, provide power supply by variable voltage source to electric bridge, the size of voltage source output voltage can regulate by knob, and can on voltage source voltage display screen, show, semiconductor thermistor or metal thermo-sensitive resistance are placed in the glass flume of one end sealing, it is characterized in that: bath of glass cell wall adopts double-decker, centre is evacuated, to play good heat insulation effect, in glass flume, in heat transfer liquids, top part arranges semiconductor refrigerating plant, be used for Cooling Heat Transfer liquid, part arranges a heating arrangement on the lower, be used for heating heat transfer liquids, center section arranges a temperature sensor, be used for measuring the temperature of heat transfer liquids, semiconductor cooling device, heating arrangement and temperature sensor are connected with temperature controller by interface respectively, can set the temperature of heat transfer liquids by the button on temperature controller.
2. the experimental provision that utilizes nonequilibrium bridge design resistance thermometer according to claim 1, is characterized in that: the output terminal concatenation operation amplifier one of electric bridge, as a reverse voltage amplifier, voltage amplification factor can be by changing adjustable feedback resistance R
fand adjustable input resistance R
isize regulate, the output voltage of electric bridge is amplified, then exports through the operational amplifier two as output buffer, on the voltage display screen of digital voltmeter, show, by suitably choosing arm resistance, adjustable feedback resistance R
fand adjustable input resistance R
ivalue, can make the magnitude of voltage that the voltage display screen of digital voltmeter shows is just in time the celsius temperature scale of object under test.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420309352.0U CN203882485U (en) | 2014-06-04 | 2014-06-04 | Experimental device for designing resistance thermometer by employing non-balanced bridge |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420309352.0U CN203882485U (en) | 2014-06-04 | 2014-06-04 | Experimental device for designing resistance thermometer by employing non-balanced bridge |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203882485U true CN203882485U (en) | 2014-10-15 |
Family
ID=51682961
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420309352.0U Expired - Fee Related CN203882485U (en) | 2014-06-04 | 2014-06-04 | Experimental device for designing resistance thermometer by employing non-balanced bridge |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203882485U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109991265A (en) * | 2017-12-30 | 2019-07-09 | 光力科技股份有限公司 | A kind of self-regulation thermal conductivity gas sensor and gas-detecting device |
-
2014
- 2014-06-04 CN CN201420309352.0U patent/CN203882485U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109991265A (en) * | 2017-12-30 | 2019-07-09 | 光力科技股份有限公司 | A kind of self-regulation thermal conductivity gas sensor and gas-detecting device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102495650A (en) | Multi-stage refined precise temperature control device and control method | |
| CN107941363B (en) | Temperature pick-up device and method based on program-controlled double constant-current supplies | |
| CN109752113B (en) | Sheet temperature sensor, position determining method and circuit design method in application of sheet temperature sensor | |
| CN106644172A (en) | Thermocouple cold-end thermostat device for portable field calibration and control method thereof | |
| CN109443601A (en) | High-precision multipoint temperature measuring system and temperature correction method based on thermal resistance | |
| CN207263437U (en) | A kind of multi-fuel automobile cold start charge heating performance detection experimental system | |
| CN104677522A (en) | Scene automatic calibration system and method for integrative temperature transmitter | |
| CN110987239A (en) | Temperature measurement detection device for terminal base of electric energy meter | |
| CN201590181U (en) | Self-adapting controllable constant-temperature heat source | |
| CN104064076A (en) | Experimental facility using unbalanced bridge to design electrical resistance thermometer | |
| CN205809732U (en) | A kind of attemperating unit of protein analyzer | |
| CN203882485U (en) | Experimental device for designing resistance thermometer by employing non-balanced bridge | |
| CN104296885A (en) | Temperature tester | |
| CN104122469B (en) | Method for increasing measured seebeck coefficient accuracy of thermoelectric material | |
| CN104107032A (en) | Electronic thermometer and temperature calibration method thereof | |
| CN208537050U (en) | A kind of multichannel three-wire system platinum resistance thermometer sensor, temperature measuring equipment | |
| CN103592056A (en) | Temperature calibration instrument based on temperature differences | |
| CN201845483U (en) | Multi-functional temperature control experiment instrument | |
| Nikolic et al. | A thermal sensor for water using self-heated NTC thick-film segmented thermistors | |
| CN205176246U (en) | Conductivity meter self -calibration system | |
| CN202018348U (en) | Temperature sensor comprehensive verification bench | |
| CN204556709U (en) | A kind of proving installation of nitrogen oxide sensor chip pumps electric current | |
| CN207163947U (en) | Flow thermal conductivity coefficient measuring instrument | |
| CN208140203U (en) | A kind of gas mass flow measuring device based on improvement temperature-compensation method | |
| CN206649794U (en) | Thermistor temp characteristic curve demonstrator |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20141015 Termination date: 20150604 |
|
| EXPY | Termination of patent right or utility model |