A portable temperature calibration device

Abstract

The present invention discloses a portable temperature calibration device, comprising a housing; a circuit cavity is provided on the upper part of the housing; the middle position of the bottom surface of the circuit cavity is connected to the top of a semiconductor refrigeration plate; the bottom of the semiconductor refrigeration plate is connected to the inner side of the bottom of the housing; the circuit cavity and the semiconductor refrigeration plate divide the interior of the housing into two measuring cavities in the vertical direction; liquid water is pre-injected into the measuring cavity; the top of each measuring cavity has two openings spaced front and back, and a measuring sleeve is inserted into each opening; a fixing clamp is installed at the lower part of each measuring sleeve, and the fixing clamp is used to clamp the temperature sensor to be calibrated and the calibrated temperature sensor; the side walls around the lower part of each measuring sleeve are spaced apart with a plurality of circular holes. The portable temperature calibration device disclosed by the present invention can calibrate the temperature sensor to be calibrated directly at the environment site where it needs to be installed, without the need to transport it to the site for installation after the calibration is completed in the laboratory or factory.

Description

Technical Field

[0001] The invention relates to the technical field of temperature calibration, and in particular to a portable temperature calibration device. Background Art

[0002] With the continuous development and progress of science and technology, smart homes and smart buildings are gradually emerging. Sensors are widely used in various fields of life and industry, especially temperature sensors, which are used in various types of heat exchange equipment and household air conditioners. Especially in large shopping malls, there are a large number of temperature sensors. If they are damaged, it is very troublesome to replace the entire sensor line, and it is easy to damage the probe when reinstalling it, resulting in inaccurate data.

[0003] In a large cold storage (such as a three-dimensional cold storage), the space is huge. There are many kinds of stored items. Different types and properties of items are cooled and stored at different temperatures to avoid damage to food and other items. The temperature monitoring of each storage area is particularly strict. If the temperature monitoring fails, it will lead to immeasurable losses. Therefore, the accuracy of the temperature is particularly important.

[0004] However, existing temperature sensors are all installed as finished products and are used directly on-site after being calibrated in the factory. This type of thermometer is expensive, and it is impossible to know whether the calibrated temperature sensor is accurate, whether the error is within the allowable range, and whether it can achieve a good test effect in the project. In addition, the temperature sensor is easily damaged during transportation, and replacing a new temperature sensor will result in high time and transportation costs.

[0005] Therefore, there is an urgent need for a portable temperature calibration device that can calibrate the temperature sensor to be calibrated directly at the environment where it needs to be installed, without the need to transport it to the site for installation after calibration in a laboratory or factory. Summary of the invention

[0006] The purpose of the present invention is to provide a portable temperature calibration device in view of the technical defects in the prior art.

[0007] To this end, the present invention provides a portable temperature calibration device, comprising a hollow rectangular parallelepiped housing;

[0008] A longitudinally distributed circuit cavity is provided in the middle of the upper part of the housing;

[0009] The middle position of the bottom surface of the circuit cavity is connected to the top of the vertically placed semiconductor cooling sheet;

[0010] The bottom of the semiconductor cooling sheet is connected to the inner side of the bottom of the shell;

[0011] The circuit cavity and the semiconductor cooling sheet divide the interior of the housing into two measuring cavities distributed on the left and right in the vertical direction;

[0012] The measuring cavity is pre-injected with liquid water;

[0013] The top of each measuring cavity has two openings spaced apart from each other, and a measuring sleeve is inserted into each opening;

[0014] A fixing clamp is installed at the bottom of each measuring sleeve, and the fixing clamp is used to clamp the temperature sensor to be calibrated and the temperature sensor that has been calibrated;

[0015] The side walls around the lower part of each measuring sleeve are provided with a plurality of circular holes spaced from top to bottom.

[0016] Wherein, the outer shell is a transparent outer shell.

[0017] The measuring end of the temperature sensor to be calibrated and the measuring end of the temperature sensor that has been calibrated do not contact the inner wall of the measuring sleeve and are located at the same level.

[0018] Wherein, a circuit board is arranged at the bottom of the circuit cavity;

[0019] The data signal acquisition end of the circuit board is connected to the signal output end of the temperature sensor to be calibrated and the signal output end of the calibrated temperature sensor through signal lines respectively.

[0020] Wherein, a power source is arranged at intervals above the circuit board, and the power source is connected to the circuit board;

[0021] Just above the power supply, there is an LCD display installed;

[0022] The liquid crystal display screen is connected to the circuit board and is used to display the temperature values ​​of the temperature sensor to be calibrated and the temperature values ​​of the calibrated temperature sensor collected and transmitted by the circuit board.

[0023] Wherein, heat exchangers are arranged on the left and right sides of the semiconductor refrigeration plate;

[0024] Thermal conductive silicone grease is applied between the heat exchanger and the semiconductor refrigeration plate.

[0025] In it, the two measuring cavities are completely separated;

[0026] The upper side of the measuring sleeve is closed and the top is open.

[0027] It can be seen from the technical solution provided by the present invention that, compared with the prior art, the present invention provides a portable temperature calibration device, which can calibrate the temperature sensor to be calibrated directly at the environment site where it needs to be installed, without the need to transport it to the site for installation after calibration in the laboratory or factory, thereby enhancing the user's product experience and having great production practice significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of the structure of a portable temperature calibration device provided by the present invention;

[0029] Figure 2 A top view of a portable temperature calibration device provided by the present invention;

[0030] In the figure, 1 is a measuring sleeve, 2 is a liquid crystal display, 3 is a power supply, 4 is a circuit board, and 5 is a hole;

[0031] 6 is a fixing clip, 7 is a calibrated temperature sensor, 8 is a heat exchanger, 9 is a semiconductor cooling sheet, and 10 is a housing;

[0032] 11 is a temperature signal access port, and 12 is a measurement cavity. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and implementation modes.

[0034] See also Figure 1 , Figure 2 , the present invention provides a portable temperature calibration device, comprising a hollow rectangular parallelepiped housing 10;

[0035] The upper middle position of the housing 10 has a circuit cavity 20 distributed longitudinally;

[0036] The middle position of the bottom surface of the circuit cavity 20 is connected to the top of the vertically placed semiconductor cooling sheet 9;

[0037] The bottom of the semiconductor cooling sheet 9 is connected to the inner side of the bottom of the housing 10;

[0038] The circuit cavity 20 and the semiconductor cooling sheet 9 connected to each other vertically divide the housing 10 into two measuring cavities 12 distributed on the left and right.

[0039] The measuring cavity 12 is pre-injected with liquid water (such as pure water, which may be filled);

[0040] The two measuring cavities 12 are completely separated;

[0041] The top of each measuring cavity 12 has two openings spaced apart from each other, and a measuring sleeve 1 is inserted into each opening;

[0042] A fixing clamp 6 is installed at the bottom of each measuring sleeve 1, and the fixing clamp 6 is used to clamp the temperature sensor to be calibrated and the calibrated temperature sensor 7;

[0043] It should be noted here that the temperature sensor to be calibrated and the calibrated temperature sensor 7 are immersed in water, and both are used to measure the temperature of the water. When the two are close to each other (for example, when the interval is 2 to 3 mm), the water temperature at their locations is consistent.

[0044] A plurality of circular holes 5 are spaced apart from top to bottom on the side walls around the lower part of each measuring sleeve 1 .

[0045] It should be noted that the fixing clip 6 is a removable temperature sensor fixing clip and can be an existing temperature sensor fixing bracket, which only needs to be placed on the measuring sleeve and clamp the temperature sensor.

[0046] In the present invention, in a specific implementation, the size of the housing 10 can be designed to be different according to different calibration quantities, and the housing 10 is preferably made of a transparent material.

[0047] In the present invention, in a specific implementation, the measuring end of the temperature sensor to be calibrated and the measuring end of the calibrated temperature sensor 7 do not contact the inner wall of the measuring sleeve 1, and are located at the same horizontal height (for example, the measuring end of the temperature sensor to be calibrated is located directly behind the calibrated temperature sensor 7).

[0048] In the present invention, in a specific implementation, a circuit board 4 (specifically, it can be an existing temperature acquisition circuit board or a temperature acquisition module) is provided at the bottom of the circuit cavity 20;

[0049] The data signal acquisition end of the circuit board 4 is connected to the signal output end of the temperature sensor to be calibrated and the signal output end of the calibrated temperature sensor 7 through signal lines.

[0050] In specific implementation, a power supply 3 is arranged above the circuit board, and the power supply 3 is connected to the circuit board 4 to provide working power for the circuit board 4 and the liquid crystal display screen 2;

[0051] Directly above the power source 3, a liquid crystal display screen 2 is installed;

[0052] The liquid crystal display screen 2 is connected to the circuit board 4 and is used to display the temperature value of the temperature sensor to be calibrated and the temperature value of the calibrated temperature sensor 7 collected and transmitted by the circuit board 4 .

[0053] In specific implementation, the rear side of the liquid crystal display screen 2 has a plurality of temperature signal access ports 11 for accessing the signal lines connected to the signal output ends of the temperature sensors to be calibrated and the signal output ends of the calibrated temperature sensors 7 .

[0054] It should be noted that the number of groups of temperature signal access ports 11 is consistent with the number of measuring sleeves 1, and each group is three, which can be used for signal transmission of thermocouple sensors and thermal resistance sensors.

[0055] It should be noted that, in the present invention, the most commonly used thermocouple and thermistor temperature signal transmission are integrated on the same circuit board, connected through different signal interfaces, and different signals are transmitted, which can realize the calibration of both the thermocouple temperature sensor to be calibrated and the thermistor temperature sensor to be calibrated, thereby enhancing the practicality and versatility of the equipment.

[0056] In specific implementation, the circuit board 4 has the most basic power supply and A / D conversion function (for example, low-power ICL7136 for A / D conversion). For example, AD590 is a commonly used current-type integrated temperature sensor. The chip integrates a temperature sensing part, an amplifier circuit, a drive circuit, and a signal processing circuit. The application of temperature sensors is very extensive, and the corresponding circuit technology of temperature sensors is also very mature. For example, the circuit board 4 can specifically adopt the circuit board on the intelligent paperless recorder of model R1000 of Hongqi Instrument Co., Ltd. The R1000 series intelligent paperless recorder can receive a variety of thermocouples, thermal resistors, voltage and current signals, and perform curve and digital recording. At present, it is widely used in industries such as medicine, petroleum, chemical industry, metallurgy, and electric power, as well as scientific research units. Compared with the traditional single temperature, its biggest feature is that it can simultaneously access multiple groups of temperature sensor signals, and can display the temperature on the display screen in real time.

[0057] In the present invention, in a specific implementation, the semiconductor cooling sheet 9 is vertically placed in the middle lower part of the entire device, and the power line end of the semiconductor cooling sheet 9 should be at the upper part.

[0058] In the present invention, in a specific implementation, the semiconductor refrigeration chip 9 can be an existing TEC1-12706 semiconductor refrigeration chip, which is used to heat the water in the measurement cavity. The specific model can also be adjusted according to the needs of customers. For example, if you want to heat up faster, you can use a semiconductor refrigeration chip with a large cooling capacity or heating capacity. On the contrary, you can choose a semiconductor refrigeration chip with a smaller power.

[0059] It should be noted that in the present invention, the vertically placed semiconductor cooling sheet 9 can achieve good heat dissipation at both the hot end and the cold end. On the hot end side, the water heated by the hot end flows upward due to the density difference, and the cold water with high density flows into the hot end at the bottom and is heated again, and the cycle repeats. On the cold end side, the water in the measuring cavity is cooled, and due to the density difference, the cold water with lower temperature moves downward, and the water with higher temperature flows into the cold end and is cooled again, and the cycle repeats.

[0060] It should be noted that due to the characteristics of semiconductor refrigeration chips, if the positive and negative poles of the semiconductor refrigeration chips are reversed, the cold end and the hot end can be exchanged. Therefore, after a measurement is completed, you only need to reverse the power supply to calibrate from low temperature to high temperature again. The original high temperature water area becomes a low temperature water area, and the original low temperature water area becomes a high temperature water area. The water area temperatures on both sides can be used alternately, and there is no need to calibrate the temperature sensor in a certain variable temperature water area as in the traditional calibration, which results in a waste of cooling or heat.

[0061] In the present invention, in specific implementation, heat exchangers 8 are provided on both the left and right sides of the semiconductor refrigeration sheet 9;

[0062] A material with high thermal conductivity such as thermal grease is coated between the heat exchanger 8 and the semiconductor refrigeration sheet 9.

[0063] It should be noted that in the present invention, in order to improve the cooling and heating efficiency of the semiconductor refrigeration plate, improve the heat exchange efficiency, and enhance the performance of the entire device, it is necessary to apply a high thermal conductivity material between the semiconductor refrigeration plate and the heat exchanger to enhance the contact between the two, reduce the contact thermal resistance between the two, improve the cooling and heating efficiency, improve the energy utilization efficiency, reduce energy consumption, increase the single use time of the equipment, and enhance the experience during use.

[0064] In specific implementation, the heat exchanger 8 can be an array-type columnar heat exchanger or a fin-type heat exchanger.

[0065] It should be noted that in the present invention, when a fin-type heat exchanger is used, the fins should be in a vertical state so that the heated water or the cooled water can flow well along the gaps between the fins due to the density difference, thereby reducing the flow resistance and improving the heat exchange efficiency.

[0066] In the present invention, in a specific implementation, the LCD display 2 can display the temperature value measured by the calibrated temperature sensor 7 (for example, a calibrated thermocouple) in the measuring sleeve 1, can display the temperature value of the temperature sensor to be calibrated (for example, a thermocouple to be measured), and can simultaneously display and record real-time data.

[0067] In specific implementation, the liquid crystal display screen 2 can be an existing liquid crystal display screen, and can also use liquid crystal blocks that are easily purchased on the market to display the corresponding temperature data.

[0068] In specific implementation, the LCD display 2 can use the integrated temperature sensor LM35DZ as a temperature measuring probe, select the low-power ICL7136 for A / D conversion and LCD drive, and use a liquid crystal block that is easily purchased on the market for display (the integrated temperature sensor can be replaced with an external temperature sensor). The LCD display 2 is used to display the actual temperature value and the temperature value of the thermocouple to be calibrated. After heating or cooling by the semiconductor refrigeration plate, a long-term temperature change curve is recorded. This curve is then compared with the change curve of the standard temperature to obtain the amount that needs to be corrected, and then the thermocouple to be calibrated is calibrated. The specific principle and process of calibrating the thermocouple will be explained in detail below, so I will not explain it in detail here.

[0069] In the present invention, in specific implementation, the power source 3 can be a lithium battery or a lead-acid battery (a battery with a larger capacity has a longer working time). The battery has a side that can be taken out and replaced with a new battery or a spare battery.

[0070] It should be noted that in the present invention, the LCD screen 2 is a display and control panel, which can display the value of the calibrated temperature sensor 7 on the screen, and can also display the value of the sensor to be calibrated, and can record and store data, and can export data from the data interface to facilitate subsequent calibration correction.

[0071] It should be noted that, in the present invention, a 12V battery is used as a power source. A 12V power source is particularly easy to obtain in life. If a lead-acid battery is used, there is no need to use a boost or reduce circuit to process, and it can be directly connected to the circuit for use. If a lithium battery is used, a boost component is required in the circuit board to boost the voltage, and the boost can work normally. Although a lithium battery requires a boost component, the capacity of a lithium battery is larger than that of a lead-acid battery, and the weight is lighter than that of a lead-acid battery, which also has great advantages. In the present invention, a detachable battery is used as a power source. In the event of insufficient power, the battery can be replaced, which provides convenience for travel measurement and avoids the situation of being unable to work due to lack of power.

[0072] In the present invention, in specific implementation, the two measuring cavities 12 are completely separated, and the interior of the cavities is liquid water;

[0073] The upper side of the measuring sleeve 1 is in a closed state and the top is open.

[0074] It should be noted that, in the present invention, only tap water needs to be added on site for calibration, and no special liquid is required. When adding water, the water level only needs to be slightly higher than the height of the semiconductor refrigeration plate 9; the hole 5 on the measuring sleeve 1 is to allow the water entering the sleeve to be evenly mixed, forming a water area with relatively uniform internal and external temperatures, thereby improving the accuracy of the measurement results.

[0075] In specific implementation, the temperature sensor to be calibrated and the calibrated temperature sensor 7 are immersed in water. The semiconductor cooling chip 9 is immersed in water.

[0076] In the present invention, in a specific implementation, the fixing clamp 6 can be an existing conventional fixing clamp, which is used to clamp the upper part of the measuring end of the temperature sensor to be calibrated and the calibrated temperature sensor, so that the measuring end of the temperature sensor to be calibrated and the measuring end of the calibrated temperature sensor are at the same height position.

[0077] It should be noted that, in order to ensure the accuracy of the calibration results, a calibrated thermocouple is used as a reference standard; the fixing clamp 6 clamps the thermocouple to be measured (i.e., the temperature sensor to be calibrated) to prevent the thermocouple from contacting the measuring sleeve, which may lead to inaccurate measurement results. The measuring end of the temperature sensor to be calibrated should be completely in the water and not in contact with any surface. The thermocouple to be calibrated and the calibrated thermocouple (i.e., the calibrated temperature sensor) are placed at the same height to ensure that the measured temperature is the temperature of the same water area, thereby improving the accuracy of the calibration.

[0078] Based on the above technical solutions, it can be seen that the present invention adopts a semiconductor cooling and heating method, which can not only generate heat and cold at the same time and realize the simultaneous calibration of multiple sensors, but also the whole device is small and convenient, easy to carry and use, and therefore, it is a good calibration device that can be applied to large buildings or occasions with many temperature sensors. The convenient technical solution solves the shortcomings of the existing calibration equipment that is large in size and cannot be carried.

[0079] It should be noted that, by applying the present invention, for problematic temperature sensors or temperature probes that are inconvenient to replace, the original detection head can be directly removed, and then a new probe can be directly welded on the original thermocouple wire, and calibration can be performed directly at the measuring point. The user does not need to run back and forth or repeatedly install, which is convenient and quick.

[0080] It should be noted that the present invention adopts a semiconductor cooling and heating method, which can generate cold and heat simultaneously and realize the simultaneous calibration of multiple sensors. In addition, the entire device is small and convenient, easy to carry and use.

[0081] In order to more clearly understand the technical solution of the present invention, the calibration process of the present invention is described below.

[0082] First, the power supply 3 is turned on, and water is added into the measuring cavities 12 on both sides of the housing 10 .

[0083] Next, clamp the upper part of the measuring end of the manufactured temperature sensor to be calibrated with a fixing clamp 6, and then put the fixing clamp 6 into the measuring sleeve 1, so that the measuring end of the temperature sensor to be calibrated (for example, a thermocouple to be calibrated) and the calibrated temperature sensor 7 (for example, a calibrated thermocouple) are in a close range (for example, at the same horizontal height) and cannot touch other wall surfaces, and then start the semiconductor cooling chip 9 to measure. The difference between the temperature sensor to be calibrated and the calibrated temperature sensor can be intuitively observed on the screen of the liquid crystal display 2. After a period of time, the calibration is completed, the temperature sensor to be calibrated is taken out, the data is exported, the numerical value is analyzed, and the calibrated value is determined.

[0084] Then, when performing the next set of calibration, wait for one to two minutes, switch the positive and negative poles of the semiconductor refrigeration plate to achieve the exchange of the cold end and the hot end, and perform the next calibration.

[0085] Therefore, compared with the prior art, the present invention has the following beneficial effects:

[0086] 1. The present invention adopts semiconductor refrigeration technology, which can realize the simultaneous generation of cold and heat, and can calibrate the temperature sensor in both directions, thereby speeding up the calibration.

[0087] 2. The semiconductor refrigeration plate used in the present invention has the advantage of small size, and the entire device can be made very small and easy to carry.

[0088] 3. The present invention uses the advantage of 12V low-voltage power supply by using semiconductor refrigeration plate, and does not need 220V high voltage. The power supply is easy to obtain, and there is no need to connect wires, and there is no interference from power lines.

[0089] 4. The present invention adopts a detachable power supply, which can be powered by a 12V lithium battery or a lithium battery, so there is no need to worry about the device running out of power and being unable to measure.

[0090] 5. The present invention adopts the heat pump principle of semiconductor refrigeration plate, effectively utilizes cold and heat, makes the energy utilization efficiency greater than 1, saves energy, and indirectly reduces the emission of pollutants.

[0091] To sum up, compared with the prior art, the portable temperature calibration device provided by the present invention can calibrate the temperature sensor to be calibrated directly in the environment where it needs to be installed, without the need to transport the device to the site for installation after calibration in a laboratory or factory, thereby enhancing the user's product experience and having great production practice significance.

[0092] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A portable temperature calibration device, characterized in that: A housing (10) comprising a hollow rectangular parallelepiped shape; A circuit cavity (20) extending longitudinally is provided at the middle of the upper portion of the housing (10); The middle position of the bottom surface of the circuit cavity (20) is connected to the top of the vertically placed semiconductor cooling sheet (9); The bottom of the semiconductor cooling sheet (9) is connected to the inner side of the bottom of the housing (10); The circuit cavity (20) and the semiconductor cooling sheet (9) divide the interior of the housing (10) into two measuring cavities (12) distributed on the left and right in the vertical direction; Liquid water is pre-injected into the measuring cavity (12); The top of each measuring cavity (12) has two openings spaced apart from each other, and a measuring sleeve (1) is inserted into each opening; A fixing clamp (6) is installed at the bottom of each measuring sleeve (1), and the fixing clamp (6) is used to clamp the temperature sensor to be calibrated and the calibrated temperature sensor (7); The side walls around the lower part of each measuring sleeve (1) are provided with a plurality of circular holes (5) spaced from top to bottom; The measuring end of the temperature sensor to be calibrated and the measuring end of the calibrated temperature sensor (7) are not in contact with the inner wall of the measuring sleeve (1) and are located at the same level; Heat exchangers (8) are provided on both left and right sides of the semiconductor refrigeration sheet (9); Thermal conductive silicone grease is applied between the heat exchanger (8) and the semiconductor refrigeration sheet (9).

2. The portable temperature calibration device according to claim 1, characterized in that: The housing (10) is a transparent housing.

3. The portable temperature calibration device according to claim 1, characterized in that: A circuit board (4) is arranged at the bottom of the circuit cavity (20); The data signal acquisition end of the circuit board (4) is connected to the signal output end of the temperature sensor to be calibrated and the signal output end of the calibrated temperature sensor (7) through signal lines.

4. The portable temperature calibration device according to claim 3, characterized in that: A power source (3) is arranged above the circuit board at intervals, and the power source (3) is connected to the circuit board (4); A liquid crystal display screen (2) is installed directly above the power source (3); The liquid crystal display screen (2) is connected to the circuit board (4) and is used to display the temperature value of the temperature sensor to be calibrated and the temperature value of the calibrated temperature sensor (7) collected and transmitted by the circuit board (4).

5. The portable temperature calibration device according to any one of claims 1 to 4, characterized in that: The two measuring cavities (12) are completely separated; The upper side of the measuring sleeve (1) is in a closed state and the top is open.

Images