CN112181015A - Miniature quick temperature change system - Google Patents

Miniature quick temperature change system Download PDF

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Publication number
CN112181015A
CN112181015A CN202010910863.8A CN202010910863A CN112181015A CN 112181015 A CN112181015 A CN 112181015A CN 202010910863 A CN202010910863 A CN 202010910863A CN 112181015 A CN112181015 A CN 112181015A
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China
Prior art keywords
compressor
temperature change
temperature
electromagnetic valve
miniature
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CN202010910863.8A
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CN112181015B (en
Inventor
陈俊生
刘子杨
桑梓航
王维维
朴昌浩
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Chongqing University of Post and Telecommunications
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Chongqing University of Post and Telecommunications
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    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05DSYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00Control of temperature
    • G05D23/19Control of temperature characterised by the use of electric means
    • G05D23/20Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/70Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

The invention discloses a miniature rapid temperature change system which comprises a compressor, wherein one end of the compressor is connected with a temperature and pressure sensor, one section of the temperature and pressure sensor is connected with one end of an external condenser, the other end of the external condenser is connected with one end of a filter, the other end of the filter is connected with one end of a first electromagnetic valve and one end of a second electromagnetic valve, the other end of the first electromagnetic valve is connected with one end of a capillary tube, the other end of the second electromagnetic valve is connected with an electronic expansion valve, the electronic expansion valve is connected with one end of an internal evaporator, the other end of the internal evaporator and the other end of the capillary tube are communicated with one end of the temperature and pressure sensor. The miniature rapid temperature change box system has the functions of heating, refrigerating and dehumidifying a working chamber, has uninterrupted heating and refrigerating, good stability, low cost and less energy consumption, and has the advantage of rapid temperature rise and reduction rate due to small space of the environmental box, thereby being capable of detecting the adaptability of electronic components to severe changes of environmental temperature.

Description

Miniature quick temperature change system
Technical Field
The invention belongs to the technical field of temperature change boxes, and particularly relates to a quick temperature change system of a multifunctional miniature quick temperature change box.
Background
The test box with the rapid temperature change is a rapid temperature change box, and can be used for testing the degree of the material or the composite material which can be endured under the continuous environment of extremely high temperature and extremely low temperature instantly, and testing the chemical change or physical damage caused by the expansion with heat and the contraction with cold in the shortest time. The test object can also be electronic and electric appliance parts, automatic parts, communication components, electronic chips, automobile accessories, PCB base plates, metal, chemical materials, high polymer materials, plastic cement and the like. The rapid temperature change box is widely applied to the fields of national defense industry, aerospace, household appliance industry and the like. However, after the existing temperature change box works for a long time, the temperature of the compressor can rise, so that the temperature change of the working chamber can be slower and slower, the compressor has poor stabilizing effect and is not energy-saving.
Disclosure of Invention
The invention aims to provide a multifunctional miniature quick temperature change box, which is used for solving the problems of poor stability effect and energy saving after installation caused by structural defects of most of the existing miniature quick temperature change boxes.
In order to achieve the purpose, the invention adopts the technical scheme that: a miniature rapid temperature change system comprises a compressor, wherein the output end of the compressor is connected with one end of an external condenser, the other end of the external condenser is connected with a first end of a filter, a second end of the filter is connected with one end of a second electromagnetic valve, the other end of the second electromagnetic valve is connected with one end of an electronic expansion valve, the other end of the electronic expansion valve is connected with one end of an internal evaporator, and the other end of the internal evaporator is connected with the input end of the compressor to form a refrigeration loop; the second end of the filter is also connected with one end of a first electromagnetic valve, the other end of the first electromagnetic valve is connected with one end of a capillary tube, and the other end of the capillary tube is connected with the input end of the compressor to form a compressor protection loop; the internal evaporator is arranged in the working chamber, and a heater is also arranged in the working chamber.
Furthermore, a second temperature and pressure sensor is arranged on a pipeline at the input end of the compressor, a first temperature and pressure sensor is arranged on a pipeline at the output end of the compressor, the real-time state of the refrigerant can be obtained according to the first temperature and pressure sensor and the second temperature and pressure sensor, and the superheat degree of the refrigerant at the input port of the compressor and the superheat degree of the refrigerant at the output port of the compressor are both greater than 5 ℃ through rapidly controlling the opening degree of the electronic expansion valve, so that the cooling rate is accelerated, and the energy consumption is reduced.
Further, an in-cabin temperature sensor and an in-cabin humidity sensor are further arranged in the working chamber.
Further, a condensing fan is disposed near the external condenser. An internal fan is disposed adjacent the internal evaporator. Thereby ensuring that the refrigerant is fully heat rejecting at the external condenser and fully absorbs the working chamber temperature at the internal evaporator.
Further, an ambient temperature sensor is also arranged on the external condenser. The internal evaporator is provided with a condenser temperature sensor, the upper limit and the lower limit of the working time of the heater are limited according to the environment temperature sensor, PID is carried out according to the temperature difference obtained by setting the temperature of the environment temperature sensor and the temperature change box by taking the temperature difference as a variable, the working time of the heater is controlled, and the temperature of a working chamber is ensured to quickly reach a target value; according to the condensation temperature sensor, the temperature of the condenser is guaranteed to be lower than the temperature of the working chamber by more than 5 ℃, and the dehumidification function is achieved.
The working principle of the miniature rapid temperature change box system is as follows:
the refrigeration cycle comprises the following steps: the second electromagnetic valve is opened, high-temperature and high-pressure refrigerant gas generated by the compressor exchanges heat with air through the external condenser, the refrigerant gas passes through the filter, the refrigerant gas is throttled and depressurized through the electronic expansion valve and then flows to the internal evaporator, the temperature in the working chamber is reduced, and finally the refrigerant gas returns to the compressor to complete quick refrigeration cycle.
The heating cycle principle comprises the following steps: and (5) conducting the heater to complete the thermal cycle.
In the operation process of the refrigeration cycle, the outlet temperature and the outlet pressure of the compressor are too high, the compressor is damaged, a compressor protection loop is arranged for preventing the compressor from being damaged, and the working principle is as follows: and opening the first electromagnetic valve, enabling the high-temperature and high-pressure refrigerant gas generated by the compressor to pass through the external condenser, then pass through the filter, then pass through the capillary tube, throttle and reduce the pressure, then flow to the compressor body, and return to the compressor, thereby completing the compressor protection refrigeration cycle.
In the operation process of the heating cycle, the temperature change in the working chamber is severe, and the severe temperature change in the working chamber is prevented, and the following operations are performed: and (3) switching on the heater, opening the second electromagnetic valve, enabling high-temperature and high-pressure refrigerant gas generated by the compressor to pass through the external condenser, then pass through the filter, then pass through the electronic expansion valve for throttling and pressure reduction, and then reach the internal evaporator, so that the temperature in the working chamber is reduced, and finally, the refrigerant gas returns to the compressor, so that the temperature change of the working chamber is prevented from being severe.
Compared with the prior art, the invention has the beneficial effects that:
the miniature rapid temperature change box system has the functions of refrigeration, heating, dehumidification of a working chamber, protection of a compressor and temperature stabilization, and has the advantages of uninterrupted heating, less energy consumption, low cost, sustainable heating in the working chamber and less energy consumption. The working chamber has small space, so that the temperature rise and fall speed is high, and the adaptability of the electronic component to the severe change of the environmental temperature can be detected.
Drawings
FIG. 1 is a schematic diagram of a miniature rapid temperature change box and its working principle according to the present invention;
FIG. 2 is a refrigerating schematic diagram of a miniature rapid temperature change box and its working principle according to the present invention;
FIG. 3 is a heating schematic diagram of a miniature rapid temperature change box and the working principle thereof according to the present invention;
FIG. 4 is a schematic diagram of the protection of the compressor of the miniature rapid temperature change box and the working principle thereof according to the present invention;
in the figure: 1-compressor, 2-first temperature and pressure sensor, 3-external condenser, 4-condensing fan, 5-ambient temperature sensor, 6-filter, 7-first electromagnetic valve, 8-capillary tube, 9-second electromagnetic valve, 10-electronic expansion valve, 11-condenser temperature sensor, 12-internal evaporator, 13-heater, 14-internal fan, 15-cabin humidity sensor, 16-cabin temperature sensor and 17-second temperature and pressure sensor.
Detailed Description
In order to make the invention more comprehensible, preferred embodiments are described in detail below with reference to the accompanying drawings.
The invention relates to a miniature rapid temperature change box system and a working principle thereof, as shown in figure 1, the miniature rapid temperature change box system comprises a compressor, one end of the compressor is connected with one end of an external condenser, the other end of the external condenser is connected with a filter, the other end of the filter is connected with one end of a first electromagnetic valve and one end of a second electromagnetic valve, the other end of the first electromagnetic valve is connected with one end of a capillary tube, the other end of the second electromagnetic valve is connected with one end of an electronic expansion valve, the other end of the capillary tube is connected with the other end of the compressor and one end of an internal evaporator, the other end of the electronic expansion valve is connected with one section of the internal evaporator.
As shown in fig. 2, the refrigeration cycle of the present invention is as follows:
and closing the heater, opening the second electromagnetic valve, enabling high-temperature and high-pressure refrigerant gas generated by the compressor to pass through the external condenser, then pass through the filter, then pass through the electronic expansion valve for throttling and pressure reduction, then enter the internal evaporator, cooling the working chamber, and finally return to the compressor to finish the rapid refrigeration cycle.
As shown in fig. 3, the heating cycle principle of the present invention is as follows:
the heater is conducted, the second electromagnetic valve is opened, high-temperature and high-pressure refrigerant gas generated by the compressor passes through the external condenser, then passes through the filter, and then is throttled and reduced in pressure by the electronic expansion valve to reach the internal evaporator, so that the severe temperature change of the working chamber is prevented, and the frequent start and stop of the compressor are prevented.
As shown in fig. 4, the compressor protection cycle principle of the present invention is as follows:
in the operation process of the refrigeration cycle, the outlet temperature and the outlet pressure of the compressor are too high, the compressor is damaged, and the circulation principle of preventing the compressor from being damaged is as follows: and opening the first electromagnetic valve, enabling high-temperature and high-pressure refrigerant gas generated by the compressor to pass through the external condenser, then pass through the filter, and then pass through the capillary tube for throttling and pressure reduction to reach the compressor, so that the compressor is kept at a normal temperature to prevent the temperature of the compressor from rising violently, and the compressor protection refrigeration cycle is completed.

Claims (7)

1. A miniature quick temperature change system is characterized in that: the refrigeration system comprises a compressor (1), wherein the output end of the compressor (1) is connected with one end of an external condenser (3), the other end of the external condenser (3) is connected with the first end of a filter (6), the second end of the filter (6) is connected with one end of a second electromagnetic valve (9), the other end of the second electromagnetic valve (9) is connected with one end of an electronic expansion valve (10), the other end of the electronic expansion valve (10) is connected with one end of an internal evaporator (12), and the other end of the internal evaporator (12) is connected with the input end of the compressor (1), so that a refrigeration loop is formed; the second end of the filter (6) is also connected with one end of a first electromagnetic valve (7), the other end of the first electromagnetic valve (7) is connected with one end of a capillary tube (8), and the other end of the capillary tube (8) is connected with the input end of the compressor (1) to form a compressor protection loop; the internal evaporator (12) is arranged in the working chamber, and a heater (13) is also arranged in the working chamber.
2. The miniature rapid temperature change system according to claim 1, wherein: a second temperature and pressure sensor (17) is arranged on the pipeline at the input end of the compressor (1), and a first temperature and pressure sensor (2) is arranged on the pipeline at the output end of the compressor (1).
3. A miniature rapid temperature change system according to claim 1 or 2, wherein: and an in-cabin temperature sensor (16) and an in-cabin humidity sensor (15) are also arranged in the working chamber.
4. The miniature rapid temperature change system according to claim 3, wherein: and a condensing fan (4) is arranged near the external condenser (3).
5. The miniature rapid temperature change system according to claim 3, wherein: an internal fan (14) is disposed adjacent the internal evaporator (12).
6. The miniature rapid temperature change system according to claim 4 or 5, wherein: and an ambient temperature sensor (5) is also arranged on the external condenser (3).
7. The miniature rapid temperature change system according to claim 6, wherein: and a condenser temperature sensor (11) is arranged on the internal evaporator (12).
CN202010910863.8A 2020-09-02 2020-09-02 Miniature quick temperature change system Active CN112181015B (en)

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Application Number Priority Date Filing Date Title
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