Large-temperature-span mixed working medium refrigerating and heating system and cold and hot double-temperature cabinet

Abstract

The invention provides a large-temperature-span mixed working medium refrigerating and heating system and a cold and hot double-temperature cabinet, and relates to the technical field of cold and hot double-temperature cabinets. According to the large-temperature-span mixed working medium refrigerating and heating system, a single-stage steam compression and primary throttling refrigerating system is adopted, automatic switching of a refrigerating mode and a heating mode is achieved through ingenious pipeline design and cooperative control over valves (the valves A1, A2 and B3 and the valves B1 and B3), a complex four-way reversing valve is not needed, and refrigerant leakage caused by the adoption of the four-way reversing valve is avoided; the whole system is simple and compact in structure, all the used components are mature product components, and the characteristics of low cost, high reliability and easy maintenance of the system are ensured while high performance is obtained. The system is provided with an intelligent control system composed of a controller, a plurality of temperature sensors and a plurality of pressure sensors. The rotating speed of the compressor is dynamically adjusted by monitoring the environment temperature, the temperature of the heat exchanger and the exhaust pressure of the compressor in real time according to preset multi-condition judgment logic.

Description

Technical Field

[0001] This invention relates to the field of dual-temperature cabinet technology, specifically to a large-temperature-span mixed working fluid refrigeration and heating system and a dual-temperature cabinet. Background Technology

[0002] With the booming development of the food distribution industry, convenience stores, supermarkets and other commercial venues are increasingly demanding dual-temperature cabinets that combine refrigeration and heating functions. These devices typically require maintaining a low temperature of 0℃-10℃ inside the cabinet in refrigeration mode, while providing insulation or heating functions of 30℃-65℃ in heating mode, resulting in a wide operating temperature range for the system.

[0003] Currently, the existing technical solutions for achieving this function in the market mainly fall into the following categories: The first type of solution combines compressor refrigeration with independent electric heating elements for heating. It utilizes a vapor compression cycle for refrigeration, while heating is achieved through additional resistance heating elements such as heating wires or heating tubes. Although this solution has a simple structure, the heating process essentially converts electrical energy directly into heat energy, resulting in low efficiency and huge energy consumption.

[0004] The second type of solution uses a compressor for both cooling and heating, employing a single-component refrigerant (such as R134a) and switching between cooling and heating modes via a four-way reversing valve. However, traditional refrigerants like R134a have high global warming potential (GWP) values ​​(e.g., R134a has a GWP of 1430), resulting in poor environmental performance. More importantly, when operating across large temperature ranges exceeding 100°C, from an evaporation temperature of around -20°C (corresponding to a cabinet temperature of 0°C) to a condensation temperature of approximately 90°C (corresponding to a cabinet temperature of 65°C), single-stage compression systems face severe challenges due to excessively high discharge pressure and temperature, as well as excessively high pressure ratios. This leads to a sharp decline in the system's coefficient of performance (COP), a significant increase in energy consumption, reduced operational reliability, and very poor heating efficiency at low ambient temperatures.

[0005] The third type of solution is thermoelectric cooling / heating technology based on the Peltier effect. While this technology can achieve switching between cooling and heating, its heating power is usually low, the heating rate is slow, and the sides of the cabinet heat up during heating, which has an adverse impact on the surrounding environment. Therefore, this technology is currently mostly limited to the field of micro-refrigeration or places with special requirements, and it is difficult to meet the power and performance requirements of commercial dual-temperature cabinets.

[0006] In summary, existing technical solutions generally suffer from prominent problems when addressing the cooling and heating demands of large temperature spans, including high energy consumption, low efficiency, poor environmental performance, insufficient cooling capacity, excessive system pressure ratio and exhaust pressure, and poor reliability. While solutions such as cascaded cycles and multi-stage compression cycles exist to address the large temperature span issue, their system structures are complex and their costs are high.

[0007] In contrast, using non-azeotropic mixed working fluids is considered a highly promising solution because it offers advantages over pure working fluids in reducing system pressure ratio, increasing system COP, and enhancing cycle temperature rise. Furthermore, the system structure is relatively simple, operating at lower pressures, and mature components can be reused, resulting in lower costs. Therefore, developing a high-efficiency, reliable, high-temperature-span refrigeration and heating system based on environmentally friendly mixed working fluids has become an urgent need for technological development in this field. Summary of the Invention

[0008] The purpose of this invention is to provide a large-temperature-span mixed working fluid refrigeration and heating system and a dual-temperature cabinet to solve the problems of high energy consumption, low efficiency, poor environmental performance, insufficient cooling capacity, excessive system pressure ratio and exhaust pressure, and poor reliability in existing large-temperature-span single-stage refrigeration and heating systems.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A large-temperature-span mixed working fluid refrigeration and heating system includes a compressor, an external heat exchanger, an internal heat exchanger, a first capillary tube, a liquid storage tank, and a second capillary tube, wherein the external heat exchanger is located outside the box and the internal heat exchanger is located inside the box. The compressor's discharge pipe is connected to the inlet of the external heat exchanger via the first pipe, and valve A1 is connected in series on the first pipe. The outlet of the external heat exchanger is connected to the inlet of the internal heat exchanger via the second pipe, and valve A2 and the first capillary tube are connected in series on the second pipe. The outlet of the internal heat exchanger is connected to one end of the liquid storage tank via the third pipe, and valve A3 is connected in series on the third pipe. The other end of the liquid storage tank is connected to the compressor's suction pipe. The compressor's discharge pipe is connected to the inlet of the heat exchanger inside the box via the fourth pipe, and valve B1 is connected in series on the fourth pipe. The outlet of the heat exchanger inside the box is connected to the inlet of the heat exchanger outside the box via the fifth pipe, and the second capillary tube and valve B2 are connected in series on the fifth pipe. The outlet of the heat exchanger outside the box is connected to one end of the liquid storage tank via the sixth pipe, and valve B3 is connected in series on the sixth pipe.

[0010] Preferably, a first filter is connected in series on the second pipeline and at the front end of the first capillary.

[0011] Preferably, a second filter is connected in series on the fifth pipe and at the front end of the second capillary.

[0012] Preferably, a first temperature sensor for monitoring ambient temperature T1 is installed on the outside of the housing, a second temperature sensor for monitoring the temperature T2 of the external heat exchanger is installed at the location of the external heat exchanger, a third temperature sensor for monitoring the temperature T3 of the internal heat exchanger is installed at the location of the internal heat exchanger, and a pressure sensor for monitoring the real-time discharge pressure P1 of the compressor is connected to the compressor's discharge pipe. It also includes a controller, which is connected to the control terminal of the compressor. The controller is also connected to the first temperature sensor, the second temperature sensor, the third temperature sensor, and the pressure sensor.

[0013] Preferably, the maximum discharge pressure of the compressor is defined as P; In heating mode, when T3≤T1 and P1≤P, the compressor increases its speed to the maximum allowable speed at the set speed; when T3≤T1 and P1>P, the compressor decreases its speed at the set speed; when T3>T1 and P1≤P, the compressor increases its speed to the maximum allowable speed at the set speed; when T3>T1 and P1>P, the compressor decreases its speed at the set speed; when T2≥T1, the compressor stops. In cooling mode, when T3≥T1 and P1≤P, the compressor increases its speed to the maximum allowable speed at the set speed; when T3≥T1 and P1>P, the compressor decreases its speed at the set speed; when T3<T1 and P1≤P, the compressor increases its speed to the maximum allowable speed at the set speed; when T3<T1 and P1>P, the compressor decreases its speed at the set speed; when T2≤T1, the compressor stops.

[0014] Preferably, the compressor's suction muffler is provided with a first air inlet and a second air inlet that are connected to the compressor's suction pipe, with the first air inlet located on the motor side of the compressor. The distance from the compressor's suction pipe through the second intake port to the compressor cylinder is less than the distance from the compressor's suction pipe through the first intake port to the compressor cylinder, and / or, the cross-sectional area of ​​the second intake port is greater than the cross-sectional area of ​​the first intake port.

[0015] Preferably, in heating mode, the refrigerant flow rate is Q, and the refrigerant is drawn into the compressor through the second air inlet and the first air inlet. The refrigerant drawn in through the first air inlet is heated when it passes through the compressor motor. In cooling mode, the refrigerant flow rate is q. If Q is greater than q, the refrigerant is drawn into the compressor through the second inlet, or the refrigerant is drawn into the compressor through both the second and first inlets.

[0016] Preferably, the refrigerant used in the large-temperature cross-flow mixed working fluid refrigeration and heating system is a binary hydrocarbon mixed working fluid, which includes one or both of propane and propylene.

[0017] Preferably, the refrigerant used in the large-temperature cross-flow mixed working fluid refrigeration and heating system is a binary hydrocarbon mixed working fluid, which includes one or at least two of n-butane, n-pentane, isopentane, and n-hexane.

[0018] A dual-temperature cabinet includes the aforementioned large-temperature-span mixed working fluid refrigeration and heating system.

[0019] Compared with the prior art, the large-temperature cross-temperature mixed working fluid refrigeration and heating system and the dual-temperature cabinet provided by the present invention have the following significant advantages: 1. This invention employs a single-stage vapor compression and single-throttling refrigeration system. Through ingenious piping design and coordinated control of valves (valve A1-valve A3, valve B1-valve B3), it achieves automatic switching between cooling and heating modes, eliminating the need for complex four-way reversing valves and avoiding refrigerant leakage caused by using four-way reversing valves. The entire system has a simple and compact structure, and all components used are mature products. While achieving high performance, it also ensures the system's low cost, high reliability, and ease of maintenance.

[0020] 2. The system of this invention is equipped with an intelligent control system consisting of a controller, multiple temperature sensors, and pressure sensors. By monitoring the ambient temperature, heat exchanger temperature, and compressor discharge pressure in real time, and dynamically adjusting the compressor speed based on preset multi-condition judgment logic, it ensures rapid cooling / heating response to meet usage requirements. Furthermore, it strictly limits the discharge pressure within a safe range, preventing the system from operating under high pressure ratios and high loads for extended periods. Thus, while pursuing high efficiency, it fundamentally improves the long-term operational reliability and lifespan of the system.

[0021] 3. This invention, by employing a specific binary hydrocarbon mixture and optimizing the system loop design, enables the refrigerant to perform both heating (heating temperature 40℃-65℃) and cooling (cooling temperature 0℃-10℃), achieving stable and efficient operation across a temperature range exceeding 100℃ (evaporation temperature up to -20℃, condensation temperature up to 90℃). Compared to traditional single-refrigerant systems such as R134a, this system offers significant advantages in reducing system pressure ratio, compressor discharge pressure, and discharge temperature, thereby greatly improving the system's coefficient of performance (COP) and operational reliability under extreme conditions, while effectively increasing cooling / heating capacity.

[0022] 4. The compressor of this invention adopts a wraparound dual-suction muffler design, with a first air inlet and a second air inlet. Through optimization of the flow path and cross-sectional area, intelligent flow distribution is achieved in both cooling and heating modes. In heating mode, the waste heat of the motor is fully utilized to heat part of the intake air, improving the exhaust temperature and heating efficiency. In cooling mode, the intake air is preferentially drawn through the path with less resistance to avoid unnecessary overheating and ensure cooling efficiency. This structure enables the system to maintain optimal performance under different operating conditions. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structural principle of the large-temperature-span mixed working fluid refrigeration and heating system according to an embodiment of the present invention; Figure 2This is a schematic diagram of the cooling mode of the large-temperature cross-mixed working fluid refrigeration and heating system according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the heating mode of the large-temperature cross-mixed working fluid refrigeration and heating system according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the operation control of a large-temperature cross-flow mixed working fluid refrigeration and heating system according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the intake silencer according to an embodiment of the present invention. Figure 1 ; Figure 6 This is a schematic diagram of the intake silencer according to an embodiment of the present invention. Figure 2 ; Figure 7 This is a diagram illustrating the heating effect of the large-temperature cross-flow mixed working fluid refrigeration and heating system according to an embodiment of the present invention at an ambient temperature of 10°C. Figure 8 This is a diagram illustrating the heating effect of the large-temperature cross-flow mixed working fluid refrigeration and heating system according to an embodiment of the present invention at an ambient temperature of 32°C. Figure 9 This is a diagram showing the cooling effect of the large-temperature cross-flow mixed working fluid refrigeration and heating system of this invention at an ambient temperature of 41°C. Detailed Implementation

[0024] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. Certain embodiments of the invention will be described more fully below with reference to the accompanying drawings, and some, but not all, of these embodiments will be shown. In fact, various embodiments of the invention can be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to enable the invention to meet applicable legal requirements.

[0025] In the description of this invention, it should be noted that the terms "inner," "outer," "upper," "lower," "front," and "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] Example: Please refer to Figures 1 to 9 As shown in the embodiment of the present invention, a large-temperature-span mixed working fluid refrigeration and heating system and a dual-temperature cabinet are provided.

[0027] A large-temperature-span mixed working fluid refrigeration and heating system includes a compressor 1, an external heat exchanger 2, an internal heat exchanger 5, a first capillary tube 4, a liquid storage tank 6, and a second capillary tube 8. The external heat exchanger 2 is located outside the box, and the internal heat exchanger 2 is located inside the box. The box is used to place the object to be refrigerated or heated, such as various cold drinks or hot drinks.

[0028] The discharge pipe of compressor 1 is connected to the inlet of external heat exchanger 2 via a first pipeline. Valve A1 is connected in series on the first pipeline, and valve A1 can open and close the first pipeline. The outlet of external heat exchanger 2 is connected to the inlet of internal heat exchanger 5 via a second pipeline. Valve A2 and a first capillary tube 4 are connected in series on the second pipeline. Valve A2 can open and close the second pipeline. A first filter 3 is connected in series on the second pipeline and at the front end of the first capillary tube 4. The outlet of internal heat exchanger 5 is connected to one end of liquid storage tank 6 via a third pipeline. Valve A3 is connected in series on the third pipeline, and valve A3 can open and close the third pipeline. The other end of liquid storage tank 6 is connected to the suction pipe of compressor 1.

[0029] The discharge pipe of compressor 1 is connected to the inlet of heat exchanger 5 inside the chamber via a fourth pipe. Valve B1 is connected in series on the fourth pipe, and valve B1 can open and close the fourth pipe. The outlet of heat exchanger 5 inside the chamber is connected to the inlet of heat exchanger 2 outside the chamber via a fifth pipe. A second capillary tube 8 and valve B2 are connected in series on the fifth pipe. Valve B2 can open and close the fifth pipe. A second filter 7 is connected in series on the fifth pipe at the front end of the second capillary tube. The outlet of heat exchanger 2 outside the chamber is connected to one end of liquid storage tank 6 via a sixth pipe. Valve B3 is connected in series on the sixth pipe, and valve B3 can open and close the sixth pipe.

[0030] The first capillary 4 has a cross-sectional area of ​​S1 and a length of D1; the second capillary 8 has a cross-sectional area of ​​S2 and a length of D2; S1 is less than S2, and D1 is greater than D2.

[0031] In cooling mode, the refrigerant temperature is low after throttling through the first capillary tube 4, achieving a better cooling effect. In heating mode, the refrigerant temperature is high and the flow rate is large after flowing through the second capillary tube 8, thereby improving heating efficiency. Since the capillary flow rate differs between cooling and heating, the system is equipped with a liquid receiver 6 to address this difference in refrigerant flow rate between the two modes.

[0032] Among them, valves A1, A2, A3, B1, B2, and B3 are set as solenoid valves, and the controller is connected to each solenoid valve to control the opening and closing of each solenoid valve.

[0033] In cooling mode, valves A1, A2, and A3 are open, while valves B1, B2, and B3 are closed. The high-temperature gas discharged from compressor 1 passes through the exhaust pipe and is cooled by heat exchanger 2 outside the chamber. Heat exchanger 2 outside the chamber acts as a condenser at this time. After being filtered by the first filter 3, the gas passes through the first capillary tube 4 for throttling and pressure reduction before entering heat exchanger 5 inside the chamber. Heat exchanger 5 inside the chamber acts as an evaporator at this time, absorbing heat and cooling the chamber. The gas then passes through the liquid receiver 6 and returns to compressor 1 through the suction pipe.

[0034] In heating mode, valves B1, B2, and B3 are open, while valves A1, A2, and A3 are closed. The high-temperature gas discharged from compressor 1 passes through the exhaust pipe and heats the interior of the chamber via heat exchanger 5. Heat exchanger 5 acts as a condenser at this time. After being filtered by the second filter 7, the gas then passes through the second capillary tube 8 for throttling and pressure reduction before entering the external heat exchanger 2. External heat exchanger 2 acts as an evaporator at this time. The gas then passes through the liquid receiver 6 and returns to compressor 1 via suction pipe.

[0035] An external temperature sensor (ambient temperature sensor) is installed on the outside of the enclosure to monitor the ambient temperature T1. A second temperature sensor (external heat exchanger temperature sensor) is installed at the location of the external heat exchanger 2 to monitor the temperature T2 of the external heat exchanger 2. A third temperature sensor (internal heat exchanger temperature sensor) is installed at the location of the internal heat exchanger 5 to monitor the temperature T3 of the internal heat exchanger 5. A pressure sensor is connected to the exhaust pipe of the compressor 1 to monitor the real-time exhaust pressure P1 of the compressor 1. The controller is connected to the control terminal of the compressor 1 via a signal cable to control the speed of the compressor 1. The controller 1 is also connected to the first temperature sensor, the second temperature sensor, the third temperature sensor, and the pressure sensor via signal cables to acquire and monitor the ambient temperature T1, the temperature T2 of the external heat exchanger 2, the temperature T3 of the internal heat exchanger 5, and the real-time exhaust pressure P1 of the compressor 1 in real time.

[0036] Define the maximum discharge pressure of compressor 1 as P.

[0037] In heating mode, when T3≤T1 and P1≤P, compressor 1 increases its speed to the maximum allowable speed at the set speed; when T3≤T1 and P1>P, compressor 1 decreases its speed at the set speed; when T3>T1 and P1≤P, compressor 1 increases its speed to the maximum allowable speed at the set speed; when T3>T1 and P1>P, compressor 1 decreases its speed at the set speed; when T2≥T1, compressor 1 stops.

[0038] In cooling mode, when T3≥T1 and P1≤P, compressor 1 increases its speed to the maximum allowable speed at the set speed; when T3≥T1 and P1>P, compressor 1 decreases its speed at the set speed; when T3<T1 and P1≤P, compressor 1 increases its speed to the maximum allowable speed at the set speed; when T3<T1 and P1>P, compressor 1 decreases its speed at the set speed; when T2≤T1, compressor 1 stops.

[0039] By adjusting the compressor speed using temperature and pressure programs, the needs for rapid cooling and heating can be met, while ensuring that the compressor's discharge pressure and pressure ratio are not excessively high, thus maintaining the compressor's reliability. In heating mode, the external heat exchanger 2 acts as an evaporator, and its temperature should be lower than the ambient temperature. If T2 ≥ T1 is detected, it indicates a potential malfunction, and compressor 1 should be shut down to prevent damage. In cooling mode, the external heat exchanger 2 acts as a condenser, and its temperature should be higher than the ambient temperature. If T2 ≤ T1 is detected, it indicates a potential malfunction, and compressor 1 should be shut down to prevent damage.

[0040] The intake silencer of compressor 1 is a wraparound double-intake silencer, which has a first intake port 11-1 and a second intake port 11-2 connected to the intake pipe of compressor 1. The first intake port 11-1 is located on the motor side of compressor 1. The distance from the intake pipe of compressor 1 through the second intake port 11-2 to the cylinder path L2 of compressor 1 is less than the distance from the intake pipe of compressor 1 through the first intake port 11-1 to the cylinder path L1 of compressor 1, and / or, the cross-sectional area of ​​the second intake port 11-2 is greater than the cross-sectional area of ​​the first intake port 11-1.

[0041] Among them, path L1 is the first air inlet 11-1—first air passage 11-3—second air chamber 11-7—air outlet 11-8—compressor cylinder 1, and path L2 is the second air inlet 11-2—second air passage 11-4—first air chamber 11-5—air hole 11-6—second air chamber 11-7—air outlet 11-8—compressor cylinder 1.

[0042] In heating mode, the refrigerant flow rate is Q. The refrigerant is drawn into the compressor through the second inlet 11-2 and the first inlet 11-1. The refrigerant drawn in through the first inlet 11-1 is heated as it passes through the motor of compressor 1. Due to the large refrigerant flow rate, a portion of the refrigerant flows through path L2, and the other portion flows through path L1. The heat generated by the operation of the motor of compressor 1 heats the portion of the refrigerant flowing through path L1, increasing the discharge temperature of compressor 1 and thus increasing the heating capacity of compressor 1.

[0043] In cooling mode, the refrigerant flow rate is q, where Q is greater than q. The refrigerant is drawn into compressor 1 through the second inlet 11-2, or through both the second inlet 11-2 and the first inlet 11-1. Due to the small refrigerant flow rate, the refrigerant preferentially flows into compressor 1 through path L2, with little or no refrigerant flowing through path L1. The refrigerant temperature on the suction side of compressor 1 is low, which avoids an increase in compressor 1 power due to overheating during suction, thus preventing an impact on the refrigeration cycle efficiency.

[0044] The refrigerant used in the high-temperature cross-contamination refrigerant cooling and heating system of this embodiment is a binary hydrocarbon refrigerant, which includes one or both of propane and propylene; or one or at least two of n-butane, n-pentane, isopentane, and n-hexane. The above-mentioned binary hydrocarbon refrigerant has an ozone depletion potential (ODP) of 0, exhibits extremely low GWP values, and does not produce environmentally harmful substances during cooling and heating processes, thus possessing excellent environmental friendliness. The refrigerant's performance is shown in Table 1.

[0045] Table 1: Performance data of refrigerants The high-temperature cross-temperature mixed refrigerant cooling and heating system in this embodiment has the following heating effect at an ambient temperature of 10°C: Figure 7 As shown, the heating effect at an ambient temperature of 32℃ is as follows: Figure 8 As shown, the cooling effect at an ambient temperature of 41℃ is as follows: Figure 9 As shown in the figure. The large-temperature cross-flow mixed working fluid refrigeration and heating system of this embodiment features fast cooling and heating speed, high efficiency, large cooling capacity, low exhaust pressure, low pressure ratio, and is safe and reliable.

[0046] A dual-temperature cabinet includes the large-temperature-span mixed working fluid refrigeration and heating system described in this embodiment.

[0047] The present invention has been described in detail above with reference to the accompanying drawings. Based on the above description, those skilled in the art should have a clear understanding of the large-temperature-span mixed working fluid refrigeration and heating system and the dual-temperature cabinet of the present invention. The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-temperature-range mixed working fluid refrigeration and heating system, characterized in that, It includes a compressor, an external heat exchanger, an internal heat exchanger, a first capillary tube, a liquid storage tank, and a second capillary tube, wherein the external heat exchanger is located outside the housing and the internal heat exchanger is located inside the housing. The compressor's discharge pipe is connected to the inlet of the external heat exchanger via the first pipe, and valve A1 is connected in series on the first pipe. The outlet of the external heat exchanger is connected to the inlet of the internal heat exchanger via the second pipe, and valve A2 and the first capillary tube are connected in series on the second pipe. The outlet of the internal heat exchanger is connected to one end of the liquid storage tank via the third pipe, and valve A3 is connected in series on the third pipe. The other end of the liquid storage tank is connected to the compressor's suction pipe. The compressor's discharge pipe is connected to the inlet of the heat exchanger inside the box via the fourth pipe, and valve B1 is connected in series on the fourth pipe. The outlet of the heat exchanger inside the box is connected to the inlet of the heat exchanger outside the box via the fifth pipe, and the second capillary tube and valve B2 are connected in series on the fifth pipe. The outlet of the heat exchanger outside the box is connected to one end of the liquid storage tank via the sixth pipe, and valve B3 is connected in series on the sixth pipe.

2. The large-temperature-range mixed working fluid refrigeration and heating system according to claim 1, characterized in that, A first filter is connected in series with the front end of the first capillary on the second pipeline.

3. The large-temperature-range mixed working fluid refrigeration and heating system according to claim 1, characterized in that, The fifth pipeline is connected in series with the second filter at the front end of the second capillary.

4. The large-temperature-range mixed working fluid refrigeration and heating system according to claim 1, characterized in that, A first temperature sensor for monitoring ambient temperature T1 is installed on the outside of the chamber, a second temperature sensor for monitoring the temperature T2 of the external heat exchanger is installed at the location of the external heat exchanger, a third temperature sensor for monitoring the temperature T3 of the internal heat exchanger is installed at the location of the internal heat exchanger, and a pressure sensor for monitoring the real-time discharge pressure P1 of the compressor is connected to the compressor's discharge pipe. It also includes a controller, which is connected to the control terminal of the compressor. The controller is also connected to the first temperature sensor, the second temperature sensor, the third temperature sensor, and the pressure sensor.

5. A high-temperature-range mixed working fluid refrigeration and heating system according to claim 4, characterized in that, Define the compressor's maximum discharge pressure as P; In heating mode, when T3≤T1 and P1≤P, the compressor increases its speed to the maximum allowable speed at a set rate. When T3≤T1 and P1>P, the compressor reduces its speed at the set speed. When T3 > T1 and P1 ≤ P, the compressor increases its speed to the maximum allowable speed at the set speed. When T3 > T1 and P1 > P, the compressor reduces its speed at the set speed. When T2 ≥ T1, the compressor stops. In cooling mode, when T3≥T1 and P1≤P, the compressor increases its speed to the maximum allowable speed at a set rate. When T3≥T1 and P1>P, the compressor reduces its speed at the set speed. When T3 < T1 and P1 ≤ P, the compressor increases its speed to the maximum allowable speed at the set speed. When T3 < T1 and P1 > P, the compressor reduces its speed at the set rate. When T2 ≤ T1, the compressor stops.

6. A high-temperature-range mixed working fluid refrigeration and heating system according to claim 1, characterized in that, The compressor's suction silencer is equipped with a first air inlet and a second air inlet that are connected to the compressor's suction pipe. The first air inlet is located on the side of the compressor's motor. The distance from the compressor's suction pipe through the second intake port to the compressor cylinder is less than the distance from the compressor's suction pipe through the first intake port to the compressor cylinder, and / or, the cross-sectional area of ​​the second intake port is greater than the cross-sectional area of ​​the first intake port.

7. A large-temperature-range mixed working fluid refrigeration and heating system according to claim 6, characterized in that, In heating mode, the refrigerant flow rate is Q. The refrigerant is drawn into the compressor through the second air inlet and the first air inlet. The refrigerant drawn in through the first air inlet is heated when it passes through the compressor motor. In cooling mode, the refrigerant flow rate is q. If Q is greater than q, the refrigerant is drawn into the compressor through the second inlet, or the refrigerant is drawn into the compressor through both the second and first inlets.

8. A high-temperature-range mixed working fluid refrigeration and heating system according to claim 1, characterized in that, The refrigerant used in the high-temperature cross-mixed refrigerant refrigeration and heating system is a binary hydrocarbon mixture, which includes one or both of propane and propylene.

9. A high-temperature-range mixed working fluid refrigeration and heating system according to claim 1, characterized in that, The refrigerant used in the high-temperature cross-mixed refrigerant refrigeration and heating system is a binary hydrocarbon mixture, which includes one or at least two of n-butane, n-pentane, isopentane, and n-hexane.

10. A dual-temperature cabinet (hot and cold), characterized in that: The system includes the large-temperature cross-mixed working fluid refrigeration and heating system as described in any one of claims 1 to 9.

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