CN201094101Y

CN201094101Y - Digital electronic thermometer

Info

Publication number: CN201094101Y
Application number: CNU2007202011792U
Authority: CN
Inventors: 沈力; 杨楠; 姜波; 刘进; 彭俊宏
Original assignee: GUIZHOU INSTITUTE OF ELECTRONIC INDUSTRY; GUIZHOU PROVINCE INSTITUTE OF MEASUREMENT
Current assignee: GUIZHOU INSTITUTE OF ELECTRONIC INDUSTRY; GUIZHOU PROVINCE INSTITUTE OF MEASUREMENT
Priority date: 2007-10-19
Filing date: 2007-10-19
Publication date: 2008-07-30
Anticipated expiration: 2017-10-19

Abstract

The utility model discloses a digital electronic thermometer which comprises a metal sleeve of which one end is coniform, a platinum resistance arranged inside at the coniform end of the metal sleeve, a testing box body connected to the other end of the metal sleeve, a control unit arranged inside the testing box body and a liquid crystal display arranged on the surface of the testing box body, wherein, the platinum resistance and the liquid crystal display are connected with the control unit through a connecting wire. Compared with a glass tube, the rigidity of the metal sleeve of the utility model is greatly improved, so that the safe reliability of the utility model when in use is higher; the operating staff can directly read temperature data from the liquid crystal display, the reading is accurate, intuitionistic and convenient. The utility model can ensure the device to meet the low power consumption requirement for using batteries to supply power; the metal sleeve and a stick type glass liquid thermometer have the same size, and the volume of the testing box is smaller, thereby being applicable to various occasions using the glass liquid thermometer in the industry. The digital electronic thermometer has simple structure, easy installation and usage.

Description

A kind of digital and electronic thermometer

Technical field

The utility model relates to a kind of measurement mechanism of temperature, particularly a kind of digital and electronic thermometer.

Background technology

Temperature is a basic physical amount, it is the most general in the industrial processes, most important technological parameter, indexs such as the quality of industrial products, output and energy consumption are all directly relevant with temperature parameter, thereby temperature survey is one of technology that applying frequency is the highest in the modern measuring technology.Present widely used glass liquid thermometer, frangible in use, safe reliability is relatively poor, and its inner liquid of broken back overflows easy contaminated environment, in addition, because glass liquid thermometer uses scale to represent, make operating personnel read the very inconvenience of temperature data of measurement, thereby make error bigger; In order to overcome these shortcomings, people develop many electrical type thermometers, but they exist power consumption big, and the volume heaviness is difficult for installing, and manipulates defectives such as comparatively loaded down with trivial details.

Summary of the invention

The technical problems to be solved in the utility model is: the digital and electronic thermometer that the safe reliability when a kind of the use is provided is higher, accuracy of reading convenient, power consumption is lower, volume is less, install easily and use, and to overcome the deficiencies in the prior art.

The utility model is to constitute like this: it comprises that an end is conical metal sleeve 1, taper shape one end inside at metal sleeve 1 is provided with platinum resistance Rpt, the other end at metal sleeve 1 is connected with a test box body 2, be provided with control module plate 3 in test box body 2 inside, be provided with LCDs 4 on the surface of test box body 2, platinum resistance Rpt, LCDs 4 are connected with control module plate 3 by connecting line 5.

In the above-mentioned digital and electronic thermometer, on the surface of test box body 2, also be provided with the operation push-button SW1 that is connected with control module plate 3 by connecting line 5.

In the aforesaid digital and electronic thermometer, on the outer tube wall of metal sleeve 1, be socketed with a locating ring 6.

In the aforesaid digital and electronic thermometer, described control module plate 3 is made of warm slowdown monitoring circuit 7, single-chip microcomputer U1, LCD MODULE LCD, battery BAT and power circuit 8; The output of temperature slowdown monitoring circuit 7 is connected with the A/D input port of single-chip microcomputer U1, and the output of single-chip microcomputer U1 is connected with LCD MODULE LCD, and battery BAT is connected with the power input of warm slowdown monitoring circuit 7, single-chip microcomputer U1, LCD MODULE LCD respectively through behind the power circuit 8.

Owing to adopt technique scheme, compared with prior art, the utility model is to be made of metal tube that platinum resistance is housed and the test box body that control module plate and LCDs are housed.The conical end that the metal tube of platinum resistance is equipped with in inside can directly insert in the medium of desiring detected temperatures, significantly improves because the hardness of metal tube is compared glass tube, makes that the safe reliability when the utility model uses is higher; Operating personnel's direct reading temperature data just on LCDs, accuracy of reading, intuitive and convenient; All devices of the present utility model are all selected the device of low-power consumption type for use, and circuit form also uses low power dissipation design, guarantee that device can satisfy to make battery-powered low power consumption requirement; In addition, metal tube diameter of the present utility model adopts and the identical size of present widely used bar type glass liquid thermometer with length, the miniature patch mode is all selected in the encapsulation of all devices of control module plate for use, make that the volume of testing cassete is less, thereby make it can be applicable to the occasion of various industrial use glass liquid thermometers; Besides, the utility model is simple in structure, only needs an operation push-button just can control, makes its installation and use easily.

Description of drawings

Fig. 1 is a structural representation of the present utility model;

Fig. 2 is the structural representation that the utility model has handle;

Fig. 3 is the circuit block diagram of the utility model control module plate;

Fig. 4 is the circuit theory diagrams of the utility model control module plate;

Being labeled as of accompanying drawing: the 1-metal sleeve, 2-tests box body, 3-control module plate, 4-LCDs, 5-connecting line, the 6-locating ring, 7-temperature slowdown monitoring circuit, 8-power circuit, 9-handle, Rpt-platinum resistance, the SW1-operation push-button, U1-single-chip microcomputer, BAT-battery, LCD-LCD MODULE.

Embodiment

Embodiment of the present utility model, it comprises existing commercially available one, and an end is arranged is conical metal sleeve 1, at the inner platinum resistance Rpt that installs of taper shape one end of metal sleeve 1, the other end at metal sleeve 1 connects a test box body 2, at control module plate 3 of test box body 2 inner installations, the control module plate is to be integrated on the circuit board, a LCDs 4 is installed on the surface of test box body 2, platinum resistance Rpt, LCDs 4 are connected with control module plate 3 by connecting line 5; An operation push-button SW1 who is connected with control module plate 3 by connecting line 5 is installed in control for convenience on the surface of test box body 2; Limit metal sleeve 1 for convenience and insert by the degree of depth of thermometric medium locating ring 6 of socket on the outer tube wall of metal sleeve 1.In order to make things convenient for metal tube 1 to insert measured medium, can connect a handle 9 with metal tube 1 is vertical, and will test box body 2 and be contained in handle 9 interior (as shown in Figure 2).Control module plate 3 of the present utility model can adopt the finished product of selling on the market to install, but preferably adopt structure as shown in Figure 3 to make assembling, during making, control module plate 3 can be made of warm slowdown monitoring circuit 7, single-chip microcomputer U1 (model is MSP430F2013PW), LCD MODULE LCD, battery BAT (battery of the present utility model can be selected common 1.5V dry cell for use) and power circuit 8; The output of warm slowdown monitoring circuit 7 is connected with the A/D input port of single-chip microcomputer U1, the output of single-chip microcomputer U1 is connected with LCD MODULE LCD, battery BAT is connected with the power input of warm slowdown monitoring circuit 7, single-chip microcomputer U1, LCD MODULE LCD respectively through behind the power circuit 8.Its power circuit 8 is made of on-off circuit, battery booster circuit, low pressure reduction mu balanced circuit, negative supply change-over circuit; On-off circuit is by triode Q1, Q2 and resistance R 1, R2, R3, R6 and operation push-button SW1 constitute, the positive pole of battery BAT is connected with the emitter of triode Q1, the minus earth of battery BAT, resistance R 1 connects between the emitter and base stage of triode Q1, the base stage of triode Q1 is connected with the collector of triode Q2 through resistance R 2, the base stage of triode Q2 is connected with the input port P1.2 of single-chip microcomputer U1 through resistance R 3, resistance R 6 is connected between the base stage and emitter of triode Q2, operation push-button SW1 is connected between the collector and emitter of triode Q2, the grounded emitter of triode Q2; The battery booster circuit is made of chip U9 (model is RT9261B), diode D1, inductance L 1, capacitor C 1, the LX end of chip U9 is connected with the Vout end of chip U9 through diode D1, inductance L 1 is serially connected between the LX end of the collector of triode Q1 and chip U9, the GND end ground connection of chip U9, the Vout end of chip U9 is connected capacitor C 1 minus earth with capacitor C 1 positive pole; Low pressure reduction mu balanced circuit is made of chip U10 (model is TPS71525), capacitor C 2, C3, the Vout end of chip U9 is connected with the input IN end of chip U10, input IN end ground connection after capacitor C 2 of chip U10, output Vout end ground connection after capacitor C 3 of chip U10, the GND end ground connection of chip U10; The negative supply change-over circuit is made of chip U8 (model is ICL7660), capacitor C 4, C5, C6, the output Vout end of chip U10 is connected with the V+ end of chip U8, the CAP+ end of chip U8 is connected with the CAP-end of chip U8 through capacitor C 4, output Vout end ground connection after capacitor C 5 of chip U8, V+ end ground connection after capacitor C 6 of chip U8, the GND end ground connection of chip U8; The battery booster circuit can be with the 1.5V boost in voltage to 3V voltage and supply with chip U10.Low pressure reduction mu balanced circuit output voltage provides the work positive supply for 2.5V and for temperature measurement circuit, single chip circuit and liquid crystal display circuit.The negative supply change-over circuit is converted to the 2.5V positive voltage-2.5V voltage and provide the work negative supply for thermometric amplifier U2, U3.Temperature slowdown monitoring circuit 7 can be by reference voltage source U11 (model be REF3112), resistance R 8, R9, R10, R11, potentiometer W1, operational amplifier U2 (model is OPA333), U3 (model is OPA333) and capacitor C 9, C10 constitutes, the output Vout end of chip U10 is connected with the input IN end of reference voltage source U11, the input Vout end of reference voltage source U11 is connected with an end of resistance R 8, the anodal connection of signal input of the other end of resistance R 8 sliding end with operational amplifier U2 by potentiometer W1 behind resistance R 9 and potentiometer W1, the other end of resistance R 8 also is connected with the signal input negative pole of operational amplifier U2, another stiff end of potentiometer W1 and the GND of reference voltage source U11 end back in parallel ground connection, capacitor C 10 is connected between operational amplifier U2 input negative pole and the output, operational amplifier U2 output is connected with the input negative pole of operational amplifier U3 through resistance R 10, the input plus earth of operational amplifier U3, be connected between the input negative pole and output of operational amplifier U3 after resistance E11 and capacitor C 9 are in parallel, the power supply input V+ end of operational amplifier U2 and operational amplifier U3 is connected with the output Vout end of chip U10 and the Vout end of chip U8 respectively with power supply input V-end, and the output terminal of operational amplifier U3 is connected with the A/D input port P1.4 of single-chip microcomputer U1.Platinum resistance Rpt is connected in parallel on capacitor C 10 two ends, form jointly-voltage conversion circuit with amplifier U2, reference voltage source U11, resistance R 8, R9 and potentiometer W1, platinum resistance Rpt works in the constant current duty, and U2 is converted to output voltage with the temperature variant resistance value of platinum resistance Rpt; Potentiometer W1 is used to measure the adjusting at zero point of temperature starting point; C10 and platinum resistance Rpt form low-pass filter, with the various high frequency interference of elimination; The voltage of U2 output enters the voltage amplifier of being made up of amplifier U3, resistance R 10, R11 and further amplifies to satisfy the level demand of subsequent conditioning circuit; C9 and negative feedback resistor R11 form low-pass filter, further suppress high frequency interference.P1.5, P1.6, the P1.7 mouth of single-chip microcomputer U1 are connected in LCD MODULE LCD, with serial mode the dut temperature value is sent into LCD MODULE LCD, the collector of triode Q1 is connected with the end of LCD MODULE LCD through resistance R 12, R13, the P1.6 mouth of single-chip microcomputer U1 is connected with the node of resistance R 12 with resistance R 12, and LCD MODULE LCD drives LCDs 4 and show the dut temperature value on LCDs 4.Single-chip microcomputer U1 pin TEST, RST, Vss and the resistance R 5 that links to each other with Vcc are connected on the socket J3, constitute DLL (dynamic link library), the pin Vcc of single-chip microcomputer U1 is connected with single-chip microcomputer U1 pin RST through resistance R 4, and J3 links to each other with the programmable device of outside just can realize the online programming of single-chip microcomputer U1.

When the utility model uses, dry cell is contained in the test box body 2, push button SW1, triode Q1 conducting, battery BAT power supply, whole temperature measurement circuit enters duty.After the single-chip microcomputer U1 work, temperature sensing circuit 7 is converted to voltage with the temperature variant resistance of platinum resistance Rpt, send into single-chip microcomputer U1 again, be converted to digital quantity through A/D, by software programming, through tabling look-up, processing such as calculating, magnitude of voltage is converted to temperature value, send temperature value to LCD MODULE LCD with serial mode at last, this moment, operating personnel can read measured temperature numerical value on LCDs 4, and the delivery outlet P1.2 of single-chip microcomputer U1 sends high level, and delivery outlet P1.2 is by R3 control triode Q2 conducting, even operation push-button SW1 discharges, still can keep triode Q1 to be in conducting state.After the predefined thermometric time finished, the delivery outlet P1.2 of single-chip microcomputer U1 became low level, and triode Q2 ends, and triode Q1 is also corresponding to be ended, and the work of entire circuit stops because of dead electricity.Push button SW1 can begin a new circulation again again.

Claims

1. digital and electronic thermometer, it comprises that an end is conical metal sleeve (1), it is characterized in that, taper shape one end inside at metal sleeve (1) is provided with platinum resistance (Rpt), the other end at metal sleeve (1) is connected with a test box body (2), be provided with control module plate (3) in test box body (2) inside, be provided with LCDs (4) on the surface of test box body (2), platinum resistance (Rpt), LCDs (4) are connected with control module plate (3) by connecting line (5).

2. digital and electronic thermometer according to claim 1 is characterized in that, also is provided with the operation push-button (SW1) that is connected with control module plate (3) by connecting line (5) on the surface of test box body (2).

3. digital and electronic thermometer according to claim 1 is characterized in that, is socketed with a locating ring (6) on the outer tube wall of metal sleeve (1).

4. digital and electronic thermometer according to claim 1 is characterized in that, described control module plate (3) is made of warm slowdown monitoring circuit (7), single-chip microcomputer (U1), LCD MODULE (LCD), battery (BAT) and power circuit (8); The output of temperature slowdown monitoring circuit (7) is connected with the A/D input port of single-chip microcomputer (U1), the output of single-chip microcomputer (U1) is connected with LCD MODULE (LCD), is connected with the power input of warm slowdown monitoring circuit (7), single-chip microcomputer (U1), LCD MODULE (LCD) respectively behind battery (BAT) the process power circuit (8).