阅读说明：本技术 一种用于标准时钟装置的温度柔性可调恒温槽 (Temperature flexible adjustable constant temperature tank for standard clock device ) 是由 徐晴 蔡奇新 纪峰 程含渺 高雨翔 宋瑞鹏 方凯杰 黄艺璇 田正其 李昕锐 于 2019-09-24 设计创作，主要内容包括：本发明公开了一种用于标准时钟装置的温度柔性可调恒温槽,包括保温槽和电路单元,保温槽为双层密封结构,外层腔体用于盛装导热介质,内层腔体放置晶体振荡器电路,保温槽外壁上设置有加热片和制冷片,保温槽内设置有温度传感器,电路单元包括信号处理单元、加热片/制冷片驱动单元和控制核心单元,信号处理单元与温度传感器相连,加热片/制冷片驱动单元与加热片和制冷片相连,控制核心单元分别与信号处理单元和加热片/制冷片驱动单元相连。本发明提供的一种用于标准时钟装置的温度柔性可调恒温槽,可以用于标准时钟装置充当晶体振荡器的容器,也可用于需要恒温的小空间环境,提高试验效率。(The invention discloses a temperature flexible adjustable thermostatic bath for a standard clock device, which comprises a heat preservation bath and a circuit unit, wherein the heat preservation bath is of a double-layer sealing structure, an outer layer cavity is used for containing a heat-conducting medium, a crystal oscillator circuit is placed in an inner layer cavity, a heating plate and a refrigerating plate are arranged on the outer wall of the heat preservation bath, a temperature sensor is arranged in the heat preservation bath, the circuit unit comprises a signal processing unit, a heating plate/refrigerating plate driving unit and a control core unit, the signal processing unit is connected with the temperature sensor, the heating plate/refrigerating plate driving unit is connected with the heating plate and the refrigerating plate, and the control core unit is respectively connected with the signal processing unit and the heating plate/refrigerating plate driving unit. The temperature flexible adjustable constant temperature groove for the standard clock device, provided by the invention, can be used as a container of a crystal oscillator for the standard clock device, can also be used in a small space environment needing constant temperature, and improves the test efficiency.)

1. A temperature flexible adjustable thermostatic bath for a standard clock device, characterized by: including heat-preserving container (1) and circuit unit (34), heat-preserving container (1) is double-deck seal structure, and outer cavity is used for splendid attire heat-conducting medium (2), and crystal oscillator circuit is placed to the inlayer cavity, be provided with heating plate (32) and refrigeration piece (33) on heat-preserving container (1) outer wall, be provided with temperature sensor (31) in heat-preserving container (1), circuit unit (34) are accepted the signal of temperature sensor (31), control heating plate (32) and refrigeration piece (33) work.

2. A temperature flexible adjustable thermostatic bath for a standard clock device according to claim 1, characterized in that: the number of the temperature sensors (31) is 3, wherein two temperature sensors (31) are positioned in the inner cavity of the heat-insulating groove (1), and one temperature sensor (31) is positioned in the outer cavity of the heat-insulating groove (1).

3. A temperature flexible adjustable thermostatic bath for a standard clock device according to claim 1, characterized in that: circuit unit (34) include signal processing unit (41), heating plate/refrigeration piece drive unit (42) and control core unit (43), signal processing unit (41) link to each other with temperature sensor (31), heating plate/refrigeration piece drive unit (42) with heating plate (32) and refrigeration piece (33) link to each other, control core unit (43) respectively with signal processing unit (41) and heating plate/refrigeration piece drive unit (42) link to each other.

4. A temperature flexible adjustable thermostatic bath for a standard clock device according to claim 1, characterized in that: the heat-conducting medium (2) in the outer-layer cavity of the heat-insulating groove (1) comprises alkylbenzene type insulating heat-conducting oil.

5. A temperature flexible adjustable thermostatic bath for a standard clock device according to claim 1, characterized in that: the models of the heating plate (32) and the refrigerating plate (33) are TEC 1-12706.

6. A temperature flexible adjustable thermostatic bath for a standard clock device according to claim 1, characterized in that: the temperature sensor (31) adopts a Pt100 platinum thermistor.

7. A temperature flexible adjustable thermostatic bath for a standard clock device according to claim 2, characterized in that: the signal processing unit (41) comprises an adding circuit, a differential circuit, an adjustable resistor R_S1、R_S2And R_S3Respectively connected with a Pt100 platinum thermistor R_Pt1、R_Pt2And R_Pt3Serially connected Vcc and ground, the addition circuit including respective operational amplifiers U₁、U₂、U₃And adder input resistor R₁、R₂、R₃Operational amplifier U₁、U₂、U₃Respectively connected in parallel with R_S1And R_Pt1、R_S2And R_Pt2And R_S3And R_Pt3The differential circuit comprises a precision operational amplifier U₄And a feedback resistorR_f、R_sFeedback resistance R₁、R₂、R₃Connected in parallel and then connected with an operational amplifier U₄Positive electrode of (1), operational amplifier U₄The negative electrode is connected with a resistor R in parallel_f、R_sOne terminal of (1), feedback resistance R₁Another end of the resistor R is grounded and feedback_sAnother end of the first switch is connected with an operational amplifier U₄To the output terminal of (a).

8. A temperature flexible adjustable thermostatic bath for a standard clock device according to claim 7, wherein: adjustable resistor R_S1、R_S2And R_S3Pt100 platinum thermistor R with resistance value of 500 omega_Pt1、R_Pt2And R_Pt3The resistance value is 100 omega at normal temperature, and the input resistor R of the addition circuit₁、R₂、R₃Is 10k omega, and a feedback resistor R_f、R_sThe resistance values are respectively 10k omega and 20k omega, and the measured 3 temperature values and the output relation are as follows:

in the formula, V_ccIs the voltage value of the high-voltage end of the voltage-dividing circuit, T₁、T₂And T₃Respectively the temperature values detected by the three temperature sensors.

9. A temperature flexible adjustable thermostatic bath for a standard clock device according to claim 1, characterized in that: the number of the heating plate/refrigeration plate driving units (42) is 2, the heating plate/refrigeration plate driving units are respectively driven to work by the heating plate (32) and the refrigeration plate (33), the heating plate/refrigeration plate driving units (42) adopt an H full-bridge circuit to form a Q circuit₁、Q₂、Q₃、Q₄The triode is operated in a saturation region and is used as an electronic switch; d₁、D₂、D₃、D₄A current leakage channel is provided for the triode for the freewheeling diode; s₁、S₂、S₃、S₄For switching on or off the signal control terminal, control Q₁And Q₄、Q₂And Q₃Are switched on or off in pairs; v₁、V₂Q is connected with the positive and negative electrodes of the heating sheet (32) or the refrigerating sheet (33) respectively for driving the current output terminal₁、Q₃Is connected with a power supply VCC, and the collector electrodes are respectively connected with Q₂、Q₄Emitter connection of, Q₂、Q₄Is connected to the ground of the power supply.

10. A temperature flexible adjustable thermostatic bath for a standard clock device according to claim 1, characterized in that: the control core unit (43) is composed of a microprocessor and a peripheral circuit thereof, and the model of the microprocessor is selected from MSP430F 149.

Technical Field

The invention relates to a temperature flexible adjustable thermostatic bath for a standard clock device, and belongs to the technical field of test instruments.

Background

The standard clock source is a device with wide application field, and has application in military affairs, aerospace, communication navigation, measurement, computers, clocks and other aspects. An oven Controlled Crystal oscillator is an active standard clock source with high stability and low drift, which is called as oven Controlled Crystal oscillator for short, and is called as ocxo (oven Controlled Crystal oscillator) in english, and is applied to occasions with high requirements on clock accuracy and stability, for example, an oven Controlled Crystal oscillator is required for a standard clock source in an electric energy meter calibration device. The core of the constant temperature crystal oscillator is a quartz crystal oscillator which is formed by using a quartz crystal resonator as a filter element, and a constant temperature tank which is a constant temperature closed environment generally provided by a heat preservation tank and a heating temperature control system.

The traditional thermostatic bath is generally heated by adopting resistance wires, and a thermistor bridge is utilized to form a differential series amplifier so as to realize temperature control. Such a thermostatic bath is generally set at a temperature much higher than the ordinary temperature because of only the heating function and considering the temperature of the working environment. In a word, the traditional thermostatic bath has the defects of long heating time before use, incapability of flexibly adjusting temperature, incapability of randomly setting temperature and very inflexible use. At present, the temperature-adjustable constant temperature bath on the market is large in size, and the temperature-adjustable constant temperature bath designed for the crystal oscillator is not available, so that when a temperature performance test needs to be carried out on the crystal oscillator, no suitable test equipment exists.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a temperature flexible adjustable constant temperature bath for a standard clock device, which can be used as a container of a crystal oscillator of the standard clock device and can also be used in a small space environment needing constant temperature, so that the test efficiency is improved.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

the utility model provides a flexible adjustable constant temperature bath of temperature for standard clock device, includes heat preservation groove and circuit unit, the heat preservation groove is double-deck seal structure, and outer cavity is used for splendid attire heat-conducting medium, and crystal oscillator circuit is placed to the inlayer cavity, be provided with heating plate and refrigeration piece on the heat preservation groove outer wall, be provided with temperature sensor in the heat preservation groove, the circuit unit includes signal processing unit, heating plate/refrigeration piece drive unit and control core unit, signal processing unit links to each other with temperature sensor, heating plate/refrigeration piece drive unit with heating plate and refrigeration piece link to each other, control core unit respectively with signal processing unit and heating plate/refrigeration piece drive unit link to each other.

The number of the temperature sensors is 3, two of the temperature sensors are positioned in the inner cavity of the heat-preservation groove, and one of the temperature sensors is positioned in the outer cavity of the heat-preservation groove.

The material of the heat preservation groove comprises stainless steel.

The heat conducting medium in the outer cavity of the heat preservation groove comprises alkylbenzene type insulating heat conducting oil.

The models of the heating plate and the refrigerating plate are TEC 1-12706.

The temperature sensor adopts a Pt100 platinum thermistor.

The signal processing unit comprises an adding circuit, a differential circuit and an adjustable resistor R_S1、R_S2And R_S3Respectively connected with a Pt100 platinum thermistor R_Pt1、R_Pt2And R_Pt3Serially connected Vcc and ground, the addition circuit including respective operational amplifiers U₁、U₂、U₃And adder input resistor R₁、R₂、R₃Operational amplifier U₁、U₂、U₃Respectively connected in parallel with R_S1And R_Pt1、R_S2And R_Pt2And R_S3And R_Pt3The differential circuit comprises a precision operational amplifier U₄And a feedback resistor R_f、R_s，U₄For precision operational amplifiers, feedback resistor R₁、R₂、R₃Connected in parallel and then connected with an operational amplifier U₄Positive electrode of (1), operational amplifier U₄The negative electrode is connected with a resistor R in parallel_f、R_sOne terminal of (1), feedback resistance R₁Another end of the resistor R is grounded and feedback_sAnother end of the first switch is connected with an operational amplifier U₄To the output terminal of (a).

Adjustable resistor resistance value is 500 omega, Pt100 platinum thermistor R_Pt1、R_Pt2And R_Pt3The resistance value is 100 omega at normal temperature, and the input resistor R of the addition circuit₁、R₂、R₃Is 10k omega, and a feedback resistor R_f、R_sThe resistance values are respectively 10k omega and 20k omega, and the measured 3 temperature values and the output relation are as follows:

in the formula, V_ccIs the high-voltage end of the voltage division circuitValue of voltage, T₁、T₂And T₃Respectively the temperature values detected by the three temperature sensors.

The number of the heating plate/refrigerating plate driving units is 2, the heating plate/refrigerating plate driving units are respectively driven to work, the heating plate/refrigerating plate driving units are formed by an H full-bridge circuit, and Q is₁、Q₂、Q₃、Q₄The triode is operated in a saturation region and is used as an electronic switch; d₁、D₂、D₃、D₄A current leakage channel is provided for the triode for the freewheeling diode; s₁、S₂、S₃、S₄For switching on or off the signal control terminal, control Q₁And Q₄、Q₂And Q₃Are switched on or off in pairs; v₁、V₂For driving current output terminals, respectively connected with positive and negative electrodes of the heating sheet or the refrigerating sheet, Q₁、Q₃Is connected with a power supply VCC, and the collector electrodes are respectively connected with Q₂、Q₄Emitter connection of, Q₂、Q₄Is connected to the ground of the power supply.

The control core unit is composed of a microprocessor and a peripheral circuit thereof, and the model of the microprocessor is selected from MSP430F 149.

The invention has the beneficial effects that: the temperature flexible adjustable thermostatic bath for the standard clock device can realize thermostatic control at the temperature lower than the ambient temperature, and overcomes the defect that the thermostatic bath can only be set at the temperature higher than the ambient temperature by adopting a resistance wire to heat in the prior art. The low thermal inertia of the semiconductor heating sheet and the refrigerating sheet is utilized, and the low specific heat capacity heat-conducting medium is matched, so that the rapid temperature adjustment can be realized. In the temperature adjusting process, the power of the heating sheet and the power of the refrigerating sheet are controlled, and fine temperature adjustment can be achieved. The invention can realize the flexible adjustment of the temperature of the thermostatic bath, and can be used for a standard clock device serving as a container of a crystal oscillator and can also be used in a small space environment needing constant temperature.

Drawings

FIG. 1 is a schematic diagram of a temperature flexible and adjustable thermostatic bath for a standard clock device according to the present invention;

FIG. 2 is a core circuit diagram of the signal processing unit of the temperature sensor of the present invention;

fig. 3 is a core circuit diagram of a heating plate/cooling plate driving unit of the present invention;

FIG. 4 is a basic workflow diagram of the control core of the present invention.

The reference numbers in the figures are as follows: 1-a heat preservation groove; 2-a heat-conducting medium; 31-a temperature sensor; 32-a heating plate; 33-a refrigerating sheet; 34-a circuit unit; 41-a signal processing unit; 42-heating plate/cooling plate driving unit; 43-control core unit.

Detailed Description

The present invention is further described with reference to the accompanying drawings, and the following examples are only for clearly illustrating the technical solutions of the present invention, and should not be taken as limiting the scope of the present invention. As shown in figure 1, the invention discloses a temperature flexible adjustable thermostatic bath for a standard clock device, which comprises a heat preservation bath 1, wherein the heat preservation bath 1 is of a double-layer sealing structure, and the heat preservation bath 1 is made of stainless steel. The outer cavity is used for containing the heat-conducting medium 2, and the crystal oscillator circuit is placed in the inner cavity, so that the heat preservation effect is achieved. The heat-conducting medium 2 can be liquid or fixed substances with different specific heat capacities as required, and the use temperature range of the thermostatic bath is met, and the heat-conducting medium in the embodiment of the invention is alkylbenzene type (benzenoid type) insulating heat-conducting oil, the boiling point of which is 170-180 ℃, and the condensation point of which is below-80 ℃ so as to meet the use temperature range of the thermostatic bath.

The temperature control system of the present invention includes a temperature sensor 31, a heating plate 32, a cooling plate 33, and a circuit unit 34. The heating plate 32 and the refrigerating plate 33 are arranged on the outer wall of the heat preservation groove 1, are semiconductor devices based on the Peltier effect, and are TEC1-12706 in model. According to the actual situation, a plurality of heating plates and a plurality of cooling plates can be arranged, wherein 1 heating plate and 1 cooling plate are arranged in the invention, and the driving signal is obtained from the circuit unit 34.

The temperature sensors 31 are arranged in the heat preservation tank 1, the temperature sensors 31 adopt Pt100 platinum thermistors for measuring the internal temperature of the heat preservation tank, a plurality of the temperature sensors are arranged according to the actual condition, 3 temperature sensors are arranged in the invention, 1 temperature sensor is arranged in the heat conducting medium of the outer layer cavity, 2 temperature sensors are arranged in the inner layer sealed space, and temperature measuring signals are respectively connected to A, B, C terminals of the circuit unit 34. The Pt100 resistance change rate was 0.385. omega./deg.C, and the resistance value was 100. omega. at 0 deg.C.

The circuit unit 34 comprises a signal processing unit 41, a heating plate/cooling plate driving unit 42 and a control core unit 43, wherein the signal processing unit 41 is connected with the temperature sensor 31 and is used for processing an analog signal of the Pt100 thermistor; the heating plate/cooling plate driving unit 42 is connected with the heating plate 32 and the cooling plate 33 and used for outputting control signals; the control core unit 43 is respectively connected with the signal processing unit 41 and the heating plate/cooling plate driving unit 42, and is used for setting the temperature value of the thermostatic bath and adjusting the temperature of the thermostatic bath to a set value.

As shown in FIG. 2, the signal processing unit 41 includes an adding circuit and a differential circuit, and an adjustable resistor R_S1、R_S2And R_S3Respectively connected with a Pt100 platinum thermistor R_Pt1、R_Pt2And R_Pt3Series Vcc and ground adjustable resistor R_S1、R_S2And R_S3The resistance is 500 omega. The addition circuit comprises operational amplifiers U respectively connected correspondingly₁、U₂、U₃And adder input resistor R₁、R₂、R₃。U₁、U₂、U₃LM358 was chosen as the operational amplifier for transforming the circuit impedance. R₁、R₂、R₃The resistance value is selected to be 10k omega for the summing circuit input resistor. Operational amplifier U₁、U₂、U₃Respectively connected in parallel with R_S1And R_Pt1、R_S2And R_Pt2And R_S3And R_Pt3In the meantime. The differential circuit comprises a precision operational amplifier U₄And a feedback resistor R_f、R_s，U₄The OP211 with low drift and high noise rejection ratio is used as a core of the addition circuit for a precise operational amplifier. R_f、R_sFor the feedback resistance, 10k Ω and 20k Ω were selected, respectively. Feedback resistor R₁、R₂、R₃Connected in parallel and then connected with an operational amplifier U₄Positive electrode of (1), operational amplifier U₄The negative electrode is connected with a resistor R in parallel_f、R_sOne terminal of (1), feedback resistance R₁Another end of the resistor R is grounded and feedback_sAnother end of the first switch is connected with an operational amplifier U₄To the output terminal of (a). According to the circuit principle, when R is_S1、R_S2、R_S3When the resistance value is set to be 100 omega, the measured 3 temperature values and the output relation are as follows:

in the formula, V_ccThe voltage value of the high-voltage end of the voltage division circuit can be 5V. T is₁、T₂And T₃Respectively the temperature values detected by the three temperature sensors.

As shown in fig. 3, the number of the heating plate/cooling plate driving units 42 is 2, and the heating plate 32 and the cooling plate 33 are respectively driven to operate. The heating plate/cooling plate driving unit 42 is formed by an H full-bridge circuit, Q₁、Q₂、Q₃、Q₄The triode is operated in a saturation region and is used as an electronic switch; d₁、D₂、D₃、D₄A current leakage channel is provided for the triode for the freewheeling diode; s₁、S₂、S₃、S₄For switching on or off the signal control terminal, control Q₁And Q₄、Q₂And Q₃Are switched on or off in pairs; v₁、V₂The driving current output terminals are respectively connected with the positive and negative electrodes of the heating plate 32 or the cooling plate 33, and correspond to the + and-terminals in fig. 1. Q₁、Q₃Is connected with a power supply VCC, and the collector electrodes are respectively connected with Q₂、Q₄Emitter connection of, Q₂、Q₄Is connected to the ground of the power supply.

The control core 43 mainly comprises a microprocessor and peripheral circuits thereof, the model of the microprocessor is selected from MSP430F149, two built-in 16-bit timers, a fast 12-bit ADC and 48I/O pins are supported, the requirements of the invention are met, and a basic working flow chart of a software program is shown in FIG. 4. Firstly, the temperature sensor 31 collects the temperature in the heat preservation tank 1, an analog signal is transmitted to the signal processing unit 41, the signal processing unit 41 converts the analog signal into a voltage signal and transmits the voltage signal to the control core unit 43, the control core unit 43 judges whether the temperature is in a set temperature range, and if so, the heating plate 32 and the refrigerating plate 33 are stopped to work through the heating plate/refrigerating plate driving unit 42; when the temperature is higher than the set temperature, the refrigerating sheet 33 is controlled to refrigerate through the heating sheet/refrigerating sheet driving unit 42; below the set temperature, the heating of the heating plate 32 is controlled by the heating plate/cooling plate driving unit 42.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.