A refrigeration system having a refrigerant redundancy adjustment function

Abstract

The application provides a refrigeration system with a refrigerant redundancy adjustment function, which comprises a fluorine pump, a liquid storage tank, an evaporator and a balance pipe, the liquid storage tank comprises an outer cylinder and an inner cylinder, the inner cylinder is located at the inner periphery of the outer cylinder, and a first communication hole is arranged on the cylinder wall of the inner cylinder to enable the inner part of the inner cylinder to communicate with the inner part of the outer cylinder; the fluorine pump is communicated between the inner part of the outer cylinder and the evaporator; one end of the balance pipe is communicated to the inner upper end of the inner cylinder, and the other end of the balance pipe is communicated to the outlet end of the evaporator; in the fluorine pump mode, the balance pipe can introduce fluid from the outlet end of the evaporator to the inner part of the inner cylinder, so that at least part of the liquid in the inner cylinder is pressed into the outer cylinder through the first communication hole to increase the liquid level height in the outer cylinder. According to the application, the liquid outlet height of the liquid storage tank is higher in the fluorine pump refrigeration operation mode, so that the fluorine pump has sufficient liquid suction height, the probability of cavitation is effectively reduced, and the problem of cavitation in the fluorine pump refrigeration mode is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of refrigeration technology, in particular to a refrigeration system with refrigerant redundancy adjustment function. BACKGROUND

[0002] With the large application of 4G and the gradual popularization of 5G, the heat dissipation of various data processing equipment is becoming larger and larger, and the cooling capacity and energy saving requirement of air conditioning equipment in data center is becoming higher and higher.

[0003] Using the outdoor natural cold source in the transition season and cold winter to cool the data center can greatly reduce the operating cost of the air conditioning equipment. Commonly, fluorine pump air conditioners are used, and in winter, the fluorine pump mode is started and the operation of the compressor is stopped to realize heat pipe refrigeration operation by driving the refrigerant with the fluorine pump, greatly reducing the operating cost of the equipment.

[0004] The fluorine pump compression refrigeration system belongs to a composite system, and the fluorine pump heat pipe system and the compression refrigeration system share an evaporator and a condenser, as well as some shared refrigerant pipelines, system components, etc.

[0005] Because the heat load of the data center fluctuates with the user usage and seasonal time, more and more computer room air conditioners now use frequency conversion technology to cope with the heat load fluctuation of the data center to ensure the constant temperature and humidity demand of the data center. However, the change of the frequency of the compressor of the refrigeration system will cause the change of the optimal refrigerant circulation amount, and generally the higher the frequency, the greater the required refrigerant circulation amount. If the optimal refrigerant filling amount under 100% load is ensured during the design and development of the refrigeration system, the optimal refrigerant filling amount under 75% or 50% or other low frequency operation conditions is relatively small, so there may be liquid accumulation in the refrigerant inside the unit under low frequency working conditions, which is not conducive to heat exchange.

[0006] Considering the liquid level requirement of the fluorine pump suction inlet, the required refrigerant filling amount under the fluorine pump mode is also relatively large, so the fluorine pump compression refrigeration system may form a refrigerant liquid retention condition under actual operating conditions, and it is necessary to consider migrating the retained refrigerant to the liquid storage tank. Similarly, under high frequency compression refrigeration mode, the refrigerant liquid retained in the liquid storage tank is released as soon as possible to participate in system circulation operation, and the fluorine pump refrigeration system also has the problem of cavitation caused by low liquid level of the refrigerant in the liquid storage tank under the fluorine pump refrigeration mode.

[0007] The above is the difference caused by the optimal refrigerant circulation amount under different operating conditions, and the problem of adjusting the redundancy of the refrigerant needs to be solved, and another problem is that the refrigerant liquid that has not been completely evaporated in the evaporator enters the gas pipeline, and the reasons and technical background are as follows:

[0008] In air conditioning refrigeration system without gas-liquid separator, preventing compressor liquid strike is an important problem. The liquid refrigerant in the evaporator enters the compressor with high-speed refrigerant gas, and the liquid strikes the compression surface of the compressor, which is easy to cause damage.

[0009] In order to prevent the liquid refrigerant in the evaporator from entering the compressor, the gas return main is usually connected above the possible highest liquid level in the evaporator gas collector main, but this is easy to cause the liquid refrigerant and lubricating oil to remain in the bottom of the gas collector main. Because the refrigerant flow in the bottom branch is small, the flow rate is low, and it cannot carry enough liquid refrigerant and / or lubricating oil to flow upward, the bottom of the gas collector main is easy to accumulate liquid refrigerant and retain part of the lubricating oil after a long running time. When the height of these liquids gradually rises, the bottom branch is easy to form a liquid seal, and the refrigerant flow that can pass is even less, thereby causing the "liquid storage" phenomenon at the bottom of the evaporator. Obviously, these liquid refrigerants will also contain more lubricating oil, which is easy to cause insufficient refrigerant circulation and insufficient oil return in the refrigeration system.

[0010] The existing patents 201920758930.1 and 201420133297.4 propose to connect an oil return pipe to the gas return main at the bottom of the evaporator gas collector assembly, and to suck the liquid accumulated at the bottom of the gas collector back to the compressor through the pressure difference. But these two patents have some problems: 1) After shutdown and standing, the high and low pressures of the air conditioning refrigeration system will gradually achieve pressure balance, and the high-pressure end will squeeze the liquid refrigerant to accumulate in the evaporator. Then the refrigerant liquid at the bottom of the evaporator is easy to return directly to the compressor suction pipe through the oil return pipe, and even to the compressor oil pool, which will cause the compressor to start with liquid in the next start-up process, and is easy to cause liquid strike, etc. 2) The size of the oil return pipe is specified, but the length of the oil return pipe is not mentioned. Only the design principle of the oil return pipe diameter is proposed. In actual design, the size and length of the oil return pipe need to be determined according to the pressure difference and the size of the return flow. The smaller the oil return pipe diameter or the longer the oil return pipe, the smaller the return flow, which may not be able to achieve safe return flow, and eventually still cause part of the refrigerant liquid and lubricating oil to accumulate at the bottom of the evaporator.

[0011] In the fluorine pump refrigeration mode, the liquid refrigerant in the evaporator that has not been completely evaporated enters the gas pipeline between the evaporator and the condenser, which is also easy to form a "liquid seal" phenomenon, causing the gas flow resistance in these gas pipelines to increase, and even affecting the gas flow, thereby causing the fluorine pump head to increase, the system energy efficiency ratio to decrease, and the system performance to decrease. Therefore, it is also necessary to try to guide the liquid refrigerant at the outlet of the evaporator out and return to the liquid pipeline.

[0012] In summary, it is urgent to solve the problems of refrigerant redundancy adjustment and the flow of liquid refrigerant at the outlet of the evaporator and the design of the system flow path in the fluorine pump compression refrigeration system, which is necessary for the optimization design of the efficient and stable operation of the fluorine pump compression refrigeration system.

[0013] Due to the technical problems of the fluorine pump refrigeration system in the prior art, such as the low liquid level of the storage tank refrigerant in the fluorine pump refrigeration mode leading to cavitation, the present application designs a refrigeration system with refrigerant redundancy adjustment function. SUMMARY

[0014] Therefore, the technical problem to be solved by the present application is to overcome the defects of the fluorine pump compression refrigeration system in the prior art, such as the low liquid level of the storage tank refrigerant in the fluorine pump refrigeration mode leading to cavitation, thereby providing a refrigeration system with refrigerant redundancy adjustment function.

[0015] In order to solve the above problems, the present application provides a refrigeration system with refrigerant redundancy adjustment function, which comprises:

[0016] The fluorine pump, the storage tank, the evaporator and the balance pipe, the storage tank comprises an outer cylinder and an inner cylinder, the inner cylinder is located in the inner periphery of the outer cylinder, and the first communication hole is arranged on the cylinder wall of the inner cylinder to communicate the inside of the inner cylinder with the inside of the outer cylinder, the fluorine pump is communicated between the inside of the outer cylinder and the evaporator, one end of the balance pipe is communicated to the inside upper end of the inner cylinder, the other end of the balance pipe is communicated to the outlet end of the evaporator, and the balance pipe can introduce fluid from the outlet end of the evaporator to the inside of the inner cylinder in the fluorine pump mode, so that at least part of the liquid in the inner cylinder is pressed into the outer cylinder through the first communication hole to increase the liquid level height in the outer cylinder.

[0017] In some embodiments,

[0018] The balance pipe is provided with a one-way valve C, which only allows fluid to flow from the outlet end of the evaporator to the inner cylinder in the balance pipe.

[0019] In some embodiments,

[0020] The float component is arranged inside the inner cylinder and floats in the liquid in the inner cylinder to rise or fall integrally with the liquid level, a lower limit position plate is arranged below the float component, a second communication hole is further arranged on the lower limit position plate, the second communication hole penetrates the upper and lower end faces of the lower limit position plate, the liquid below the lower limit position plate can enter the upper side of the lower limit position plate through the second communication hole and float the float component, when the liquid level above the lower limit position plate falls to the height of the lower limit position plate, the float component falls to the second communication hole and blocks the second communication hole.

[0021] In some embodiments,

[0022] The position of the first communication hole is lower than the height of the lower limit position plate; the second communication hole is arranged opposite to the float component in the vertical direction, and the lower end face area of the float component is greater than the cross-sectional area of the second communication hole.

[0023] In some embodiments,

[0024] The lower limit position plate is fixedly arranged on the inner wall of the inner cylinder, the outer peripheral wall of the lower limit position plate is sealingly fixed to the inner peripheral wall of the inner cylinder, the lower limit position plate can limit the downward movement of the float component, and the lower limit position plate is a single-hole plate, i.e., the number of the second communication holes is one.

[0025] In some embodiments,

[0026] The lower end of the float component is further connected with a lower connecting rod, the lower connecting rod is arranged in the second communication hole and can move up and down in the second communication hole, the outer peripheral cross-sectional area of the lower connecting rod is smaller than the cross-sectional area of the second communication hole, and the outer peripheral cross-sectional area of the lower connecting rod is smaller than the lower end face area of the float component.

[0027] In some embodiments,

[0028] An upper limit position plate is further arranged above the float component, the upper limit position plate is fixedly arranged on the inner wall of the inner cylinder, and the upper limit position plate can limit the upward movement of the float component.

[0029] In some embodiments,

[0030] The upper limiting plate is provided with a third communication hole penetrating the upper end surface and the lower end surface of the upper limiting plate, so as to communicate the space above the upper limiting plate with the space below the upper limiting plate, and to enable the liquid and / or gas below the upper limiting plate to enter the space above the upper limiting plate through the third communication hole, and also enable the liquid and / or gas above the upper limiting plate to enter the space below the upper limiting plate through the third communication hole.

[0031] In some embodiments,

[0032] The upper limiting plate is a porous plate, and the third communication hole is a plurality of third communication holes which are distributed on the upper limiting plate.

[0033] In some embodiments,

[0034] The upper end of the floating component is further connected with an upper connecting rod which is arranged in the third communication hole and can move up and down in the third communication hole, and the outer peripheral cross-sectional area of the upper connecting rod is smaller than the cross-sectional area of the third communication hole.

[0035] In some embodiments,

[0036] The floating component is a float which comprises an upper structure and a lower structure, the lower end of the upper structure is connected with the upper end of the lower structure, the upper structure is a conical structure, and the lower structure is a cylindrical structure, when the upper connecting rod and the lower connecting rod are both present, the upper end of the upper structure is connected with the lower end of the upper connecting rod, the outer peripheral cross-sectional area of the upper end of the upper structure is equal to the outer peripheral cross-sectional area of the lower end of the upper connecting rod, and the lower end of the lower structure is connected with the upper end of the lower connecting rod, the outer peripheral cross-sectional area of the lower end of the lower structure is greater than the outer peripheral cross-sectional area of the upper end of the lower connecting rod.

[0037] In some embodiments,

[0038] The floating component has a central axis, the axes of the upper connecting rod and the lower connecting rod are both coincident with the central axis, and the axes of the upper structure and the lower structure are also both coincident with the central axis.

[0039] In some embodiments,

[0040] The evaporator comprises a collecting pipe which is located at the outlet end of the evaporator, and the other end of the balance pipe is communicated to the inner bottom end of the collecting pipe.

[0041] In some embodiments,

[0042] The compressor, the condenser, a liquid inlet pipe and a liquid outlet pipe are further included, one end of the liquid inlet pipe is communicated with the condenser and the other end is communicated with the inner top end of the outer cylinder of the liquid storage tank, so that the refrigerant in the condenser can be introduced into the liquid storage tank, one end of the liquid outlet pipe is communicated with the inner bottom end of the outer cylinder of the liquid storage tank and the other end is communicated with one end of the fluorine pump.

[0043] In some embodiments,

[0044] The other end of the fluorine pump is communicated with one end of the evaporator through a first pipe, a throttle valve is arranged on the first pipe, one end of a second pipe is communicated with the liquid outlet pipe and the other end is communicated with the first pipe between the fluorine pump and the throttle valve, and the one-way valve A allowing fluid to flow only from the liquid outlet pipe to the first pipe is arranged on the second pipe; the other end of the evaporator is communicated with a third pipe, the third pipe is communicated with the suction end of the compressor through a fourth pipe, the third pipe is further communicated with the exhaust end of the compressor through a fifth pipe, the one-way valve B allowing refrigerant to flow only from the suction end to the exhaust end of the compressor is arranged on the fifth pipe, and the oil separator is arranged between the exhaust end of the compressor and the condenser.

[0045] In some embodiments,

[0046] The other end of the balance pipe is communicated with the third pipe or the fifth pipe; or the evaporator includes a gas collecting pipe, the other end of the balance pipe is communicated with the inner bottom end of the gas collecting pipe, and the inner top end of the gas collecting pipe is communicated with the third pipe.

[0047] The refrigeration system with the refrigerant redundancy adjustment function has the following beneficial effects:

[0048] 1. The present application sets the liquid storage tank to a structure including an outer cylinder and an inner cylinder, and the inner and outer cylinders are connected through a first communication hole, and combined with a balance pipe, one end of the balance pipe is connected to the outlet end of the evaporator, and the other end is connected to the upper end of the inner cylinder, which can introduce fluid with higher pressure from the outlet end of the evaporator into the upper part of the inner cylinder in the fluorine pump refrigeration mode, so that the liquid in the inner cylinder is pressed into the outer cylinder through the first communication hole by the pressure of the high-pressure refrigerant fluid, so that the refrigerant liquid level of the outer cylinder of the liquid storage tank is higher in the fluorine pump refrigeration mode, that is, the height of the liquid discharge is higher, so as to ensure that the fluorine pump has enough liquid suction height, effectively reduce the probability of cavitation, solve the problem of cavitation in the fluorine pump refrigeration mode, and in the compression refrigeration mode, the outlet end of the evaporator has lower pressure, and fluid will not be introduced into the upper part of the inner cylinder through the balance pipe, so that the liquid level of the inner cylinder rises in the compression refrigeration mode, and the liquid level in the outer cylinder drops, and the higher pressure gas in the upper part of the outer cylinder will press the liquid in the outer cylinder into the inner cylinder through the first communication hole, and the top pressure of the inner cylinder of the liquid storage tank changes in the compression refrigeration mode and the fluorine pump refrigeration mode, which automatically adjusts the required better refrigerant circulation amount in the two operation modes, without increasing the control hardware and control software, and the system pressure change is used to realize automatic balance adjustment and control the change of the refrigerant liquid storage state in the liquid storage tank, so that the inner cylinder of the liquid storage tank becomes a variable storage space for refrigerant liquid, the system has high reliability, low cost, no special control adjustment, and the liquid level in the liquid storage tank has automatic balance adjustment function in different operation modes, and solves the problem of cavitation in the fluorine pump refrigeration mode and the problem of refrigerant redundancy caused by the difference in the required refrigerant filling amount in different operation modes of the fluorine pump compression refrigeration system, and solves the control problem of the liquid level in the liquid storage tank.

[0049] 2. The application can float the floating member when the liquid level in the inner cylinder rises above the lower limit position plate, and drive the floating member to continue to rise as the liquid level rises, which is applicable to the process when the fluorine pump refrigeration mode is converted to the compression refrigeration mode. When the liquid level in the inner cylinder drops, the floating member drops together with the liquid level. When the liquid level drops to below the lower limit position plate, the floating member is limited by the lower limit position plate and cannot continue to move downward. At the same time, the floating member blocks the second communication hole, effectively preventing gas above the lower limit position plate from entering below, even into the outer cylinder, preventing the gas refrigerant from being discharged from the liquid storage tank to the fluorine pump or the evaporator, ensuring normal and effective refrigeration. The floating member and the lower limit position plate realize the functions of liquid passage and gas blocking, and can automatically realize the change of the liquid level height between the inner cylinder and the outer cylinder according to different operating modes and different pressures and liquid level heights. The change of the refrigerant liquid storage state in the liquid storage tank is automatically balanced and adjusted by using the change of the system pressure and the change of the buoyancy of the float. The refrigerant liquid level in the outer cylinder of the liquid storage tank is higher in the fluorine pump refrigeration mode, so as to ensure that the fluorine pump has sufficient liquid suction height to reduce the probability of cavitation phenomenon. The automatic balance adjustment function is provided in different operating modes, solving the problems of refrigerant liquid storage and release, and effectively solving the problem of control of the liquid level in the liquid storage tank.

[0050] 3. The other end of the balance pipe is communicated to the inner bottom end of the gas collecting pipe of the evaporator outlet, so as to guide the unevaporated refrigerant liquid at the bottom of the gas collecting pipe out, and directly guide the refrigerant liquid at the bottom of the gas collecting pipe of the evaporator in the fluorine pump refrigeration mode back to the liquid storage tank to participate in system circulation, instead of entering the gas pipeline, solving the problems of storage and release of the unevaporated refrigerant liquid at the outlet of the evaporator, and effectively solving the problems of flow path and flow system design optimization of these refrigerant liquids. BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1 is the system principle diagram of the fluorine pump double-circulation refrigeration system with refrigerant redundancy adjustment function of the application (system runs in fluorine pump mode, float drops);

[0052] Figure 2 is the system connection structure diagram of the fluorine pump double-circulation refrigeration system with refrigerant redundancy adjustment function of the application (system runs in compression mode, float floats up);

[0053] Figure 3 is Figure 1 is the structure enlarged view of the liquid storage tank part in

[0054] Figure 4 is the structure enlarged view of the liquid storage tank part in Figure 2 .

[0055] Reference signs are indicated as:

[0056] 1, compressor; 2, liquid storage tank; 3, condenser; 4, throttle valve; 5, evaporator; 6, outer cylinder; 7, inner cylinder; 8, floating member; 9, first communication hole; 10, fluorine pump; 11, check valve A; 12, check valve C; 13, oil separator; 14, inner fan; 15, check valve B; 16, capillary tube; 17, outer fan; 18, lower limit plate; 19, second communication hole; 20, lower connecting rod; 21, upper limit plate; 22, third communication hole; 23, upper connecting rod; 24, upper structure; 25, lower structure; 26, distribution head;

[0057] 101, liquid inlet pipe; 102, liquid outlet pipe; 103, balance pipe; 104, gas collecting pipe; 105, finned pipe; 106, liquid distribution pipe; 107, gas distribution pipe; 108, liquid collecting pipe; 201, first pipe line; 202, second pipe line; 203, third pipe line; 204, fourth pipe line; 205, fifth pipe line. DETAILED DESCRIPTION

[0058] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not intended to limit the present application and its application or use in any way. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present application.

[0059] It should be noted that the terms used herein are only intended to describe specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and it should also be understood that when the terms "comprise" and / or "include" are used in the specification, there is a presence of the features, steps, operations, devices, components and / or combinations thereof.

[0060] The foregoing is considered as illustrative only of the principles of the application. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the application to the exact construction and practice described. Accordingly, all such variations are intended to be included within the scope of the present application as defined in the following claims, along with full equivalents thereof.

[0061] In the description of the present application, it is to be understood that the orientation or positional relationships indicated by terms such as "front", "back", "up", "down", "left", "right", "lateral", "vertical", "horizontal", "top", "bottom", and the like are generally based on the orientation or positional relationships shown in the drawings, and are merely intended to facilitate the description and simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore cannot be construed as limiting the scope of protection of the present application. The orientation terms "inner", "outer" refer to the inner and outer relative to the contour of the components themselves.

[0062] For the convenience of description, spatial relative terms such as "over", "above", "upper surface", "upper", and the like can be used herein to describe the spatial positional relationship of one device or feature with respect to other devices or features as shown in the drawings. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the device as described in the drawings. For example, if the device in the drawings is inverted, the device described as "above" or "over" other devices or structures will be positioned "below" or "under" the other devices or structures. Thus, the exemplary term "above" can include both "above" and "below" orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0063] In addition, it should be noted that the use of the terms "first", "second", and the like do not have a special meaning, and therefore cannot be construed as limiting the scope of protection of the present application, unless otherwise stated.

[0064] As Figures 1-4As shown, the present application provides a refrigeration system with refrigerant redundancy adjustment function, which comprises:

[0065] The fluorine pump 10, the liquid storage tank 2, the evaporator 5 and the balance pipe 103, the liquid storage tank 2 comprises an outer cylinder 6 and an inner cylinder 7, the inner cylinder 7 is located in the inner periphery of the outer cylinder 6, and the first communication hole 9 is arranged on the cylinder wall of the inner cylinder 7 to enable the inner part of the inner cylinder 7 to communicate with the inner part of the outer cylinder 6, the fluorine pump 10 is communicated between the inner part of the outer cylinder 6 and the evaporator 5, one end of the balance pipe 103 is communicated to the inner upper end of the inner cylinder 7, the other end of the balance pipe 103 is communicated to the outlet end of the evaporator 5, and in the fluorine pump mode, the balance pipe 103 can introduce fluid from the outlet end of the evaporator 5 to the inner part of the inner cylinder 7 to enable at least part of the liquid in the inner cylinder 7 to be pressed into the outer cylinder 6 through the first communication hole 9 to increase the liquid level height in the outer cylinder 6.

[0066] The present application sets the liquid storage tank as a structure comprising an outer cylinder and an inner cylinder, and realizes communication between the inner and outer cylinders through the first communication hole, and combines the balance pipe, one end of the balance pipe is communicated to the outlet end of the evaporator, and the other end is communicated to the inner upper end of the inner cylinder, which can introduce the refrigerant fluid (including refrigerant gas and / or refrigerant liquid) with high pressure into the upper part of the inner cylinder from the outlet end of the evaporator in the fluorine pump refrigeration mode, so that the liquid in the inner cylinder is pressed into the outer cylinder through the first communication hole by the pressure of the high-pressure refrigerant fluid, so that the refrigerant liquid level height of the outer cylinder of the liquid storage tank is higher in the fluorine pump refrigeration operation mode, that is, the height is higher when the liquid is discharged, so as to ensure that the fluorine pump has sufficient liquid suction height, effectively reduces the probability of cavitation, solves the problem of cavitation in the fluorine pump refrigeration mode, and in the compression refrigeration mode, the outlet end of the evaporator has low pressure, and fluid is not introduced into the upper part of the inner cylinder through the balance pipe, so that the liquid level of the inner cylinder rises and the liquid level in the outer cylinder falls in the compression refrigeration mode, and the high-pressure gas in the upper part of the outer cylinder presses the liquid in the outer cylinder into the inner cylinder through the first communication hole. By changing the top pressure of the inner cylinder of the liquid storage tank in the compression refrigeration mode and the fluorine pump refrigeration mode, the required optimal refrigerant circulation amount in the two operation modes is automatically adjusted without increasing the control hardware and control software. The change of the system pressure realizes automatic balance adjustment and control of the change of the refrigerant liquid storage state in the liquid storage tank, so that the inner cylinder of the liquid storage tank becomes a variable storage space for the refrigerant liquid. The system has high reliability, low cost, no special control adjustment, and automatic balance adjustment function of the liquid level in the liquid storage tank in different operation modes, and solves the problem of cavitation in the fluorine pump refrigeration mode and the refrigerant redundancy problem caused by the difference in the required refrigerant filling amount in different operation modes of the fluorine pump compression refrigeration system. The control problem of the liquid level in the liquid storage tank is solved.

[0067] As Figure 1 andFigure 3 As shown, the liquid storage tank 2 of the present application preferably comprises a liquid inlet pipe 101, a liquid outlet pipe 102 and a cylinder body; the liquid storage tank cylinder body is composed of an inner cylinder 7 and an outer cylinder 6, the top of the inner cylinder 7 and the outer cylinder 6 are preferably fixedly and sealingly connected, the bottom of the inner cylinder 7 and the outer cylinder 6 are preferably fixedly and sealingly connected, and at least one first communication hole 9 is formed on the side of the bottom end of the inner cylinder 7, and the inner cylinder 7 and the outer cylinder 6 can only communicate through the first communication hole 9.

[0068] The liquid storage tank of the present application further comprises a balance pipe 103, which is located at the top of the liquid storage tank and preferably continuously penetrates the top of the outer cylinder 6 and the inner cylinder 7, so that the inner cylinder 7 directly communicates with the outside of the liquid storage tank through the balance pipe 103; the balance pipe 103 is preferably sealingly fixedly welded between the outer cylinder 6 and the inner cylinder 7.

[0069] In some embodiments,

[0070] The balance pipe 103 is provided with a one-way valve C12, which only allows fluid to flow from the outlet end of the evaporator 5 to the inner cylinder 7 in the balance pipe 103.

[0071] The present application can effectively prevent the gas in the inner cylinder from flowing out to the outlet end of the evaporator through the balance pipe, prevent the refrigerant liquid or gas from being pressed out through the balance pipe due to the higher pressure of the outer cylinder than the outlet end of the evaporator in the compression refrigeration mode, avoid the situation that the evaporator is short-circuited without the refrigerant passing through the evaporator, avoid the decline of refrigeration performance, and ensure the reliable and stable operation of the refrigeration mode.

[0072] As Figure 1 As shown, the fluorine pump compression refrigeration system comprising the novel liquid storage tank further comprises a balance pipe, which is connected between the outlet of the evaporator and the balance pipe inlet of the liquid storage tank, and is provided with a one-way valve C, the flow direction of which only allows the refrigerant to flow from the outlet of the evaporator to the inner cylinder space of the liquid storage tank through the balance pipe of the liquid storage tank;

[0073] In some embodiments,

[0074] The floating part 8 is arranged inside the inner cylinder 7 and floats in the liquid in the inner cylinder 7 (partly above the liquid level and partly below the liquid level) to rise or fall integrally with the liquid level, a lower limiting plate 18 is arranged below the floating part 8, a second communication hole 19 is further arranged on the lower limiting plate 18, the second communication hole 19 penetrates the upper and lower end faces of the lower limiting plate 18, the liquid below the lower limiting plate 18 can enter the upper side of the lower limiting plate 18 through the second communication hole 19 and float the floating part 8, when the liquid level above the lower limiting plate 18 falls to the height of the lower limiting plate 18, the floating part 8 falls to the second communication hole 19 and blocks the second communication hole 19.

[0075] The application can float the floating part when the liquid level in the inner cylinder rises above the lower limiting plate, and drive the floating part to continuously rise with the rising of the liquid level, which is suitable for the process when the fluorine pump refrigeration mode is converted into the compression refrigeration mode, when the liquid level in the inner cylinder falls, the floating part falls integrally with the liquid level, when the liquid level falls below the lower limiting plate, the floating part is limited by the lower limiting plate and cannot continue to move downward, at the same time, the floating part blocks the second communication hole, which can effectively prevent the gas above the lower limiting plate from entering below and even entering the outer cylinder, prevent the gas refrigerant from being discharged from the liquid storage tank to the fluorine pump or the evaporator, ensure normal and effective refrigeration, the floating part and the lower limiting plate realize the function of liquid passage and gas blocking, can automatically realize the change of the liquid level between the inner cylinder and the outer cylinder according to different operation modes and different pressures and liquid levels, use the change of the system pressure and the change of the buoyancy of the float to realize the automatic balance adjustment and control the change of the refrigerant liquid storage state in the liquid storage tank, the refrigerant liquid level in the outer cylinder of the liquid storage tank is higher in the fluorine pump refrigeration mode, so as to ensure that the fluorine pump has sufficient liquid suction height to reduce the probability of cavitation phenomenon, has the automatic balance adjustment function in different operation modes, solves the problems of refrigerant liquid storage and release, and effectively solves the control problem of the liquid level in the liquid storage tank.

[0076] In some embodiments,

[0077] The first communication hole 9 is arranged below the height of the lower limiting plate 18, the second communication hole 19 is arranged opposite to the floating part 8 in the vertical direction, and the lower end face area of the floating part 8 is greater than the cross-sectional area of the second communication hole 19.

[0078] The first communication hole is arranged below the height of the lower limit plate, so that the refrigerant liquid inside the outer cylinder can enter below the lower limit plate of the inner cylinder through the first communication hole, and then as the liquid level of the inner cylinder rises, the liquid pushes the float upwards through the second communication hole of the lower limit plate, realizing the function and effect of upward liquid passage, and the second communication hole is opposite to the vertical direction of the floating component, and the area of the lower end of the floating component is greater than the area of the second communication hole, so that the downward movement of the floating component can completely block the second communication hole, thereby preventing the gas above from entering below the lower limit plate when the liquid level in the inner cylinder drops below the lower limit plate, and further preventing the gas from entering the outer cylinder and causing the refrigeration performance to decrease.

[0079] In some embodiments,

[0080] The lower limit plate 18 is fixedly arranged on the inner wall of the inner cylinder 7, the outer peripheral wall of the lower limit plate 18 is sealingly fixed to the inner peripheral wall of the inner cylinder 7, the lower limit plate 18 can limit the downward movement of the floating component 8, and the lower limit plate 18 is a single-hole plate, i.e., the number of the second communication hole 19 is one.

[0081] The lower limit plate of the present application is preferably fixed to the inner wall of the inner cylinder, so that the downward movement of the floating component is limited by the fixed lower limit plate when the floating component moves up and down, and the lower limit plate of the present application is further preferably a single-hole plate, i.e., the number of the second communication hole is one, which can ensure that the fluid can push the floating component upwards when the liquid level rises and the fluid enters above the lower limit plate, and can also ensure that the floating component can completely block the space above and below the lower limit plate when the liquid level drops, effectively realizing the function of liquid passage and gas blocking, avoiding the gas entering below the lower limit plate and further entering the outer cylinder, and further preventing the gas from entering the evaporator and causing the refrigeration performance to decrease; the outer peripheral wall of the lower limit plate 18 is sealingly fixed to the inner peripheral wall of the inner cylinder 7 (such as by welding technology, etc., so that the second communication hole 19 is the only passage of the lower limit plate 18), so that the liquid below the lower limit plate can only enter above through the second communication hole, and the liquid above can only enter below through the second communication hole, improving the gas blocking effect of the floating component and improving the function of liquid passage and gas blocking.

[0082] In some embodiments,

[0083] The lower end of the floating component 8 is further connected with a lower connecting rod 20, the lower connecting rod 20 is arranged in the second communication hole 19 and can move up and down along the second communication hole 19, the outer peripheral cross-sectional area of the lower connecting rod 20 is smaller than the cross-sectional area of the second communication hole 19, and the outer peripheral cross-sectional area of the lower connecting rod 20 is smaller than the area of the lower end surface of the floating component 8.

[0084] The lower connecting rod is connected to the lower end of the floating component, and can be inserted into the second communication hole to guide and limit the up-down movement of the floating component, prevent the floating component from moving horizontally or tilting, ensure that the floating component can always move vertically and block the second communication hole, and realize the function of allowing liquid to pass and preventing gas from passing.

[0085] In some embodiments,

[0086] An upper limiting plate 21 is further arranged above the floating component 8, and the upper limiting plate 21 is fixedly arranged on the inner wall of the inner cylinder 7, and can limit the upward movement of the floating component 8.

[0087] The upper limiting plate is fixed on the inner wall of the inner cylinder, so that the upward movement of the floating component can be effectively limited, and the floating component is prevented from moving upward too far to cause the lower connecting rod to come out of the second communication hole, and the floating component can normally and reliably move vertically.

[0088] In some embodiments,

[0089] The upper limiting plate 21 is provided with a third communication hole 22, which penetrates the upper end face and the lower end face of the upper limiting plate 21, so as to communicate the space above the upper limiting plate 21 with the space below the upper limiting plate 21, so that the liquid and / or gas below the upper limiting plate 21 can enter the space above the upper limiting plate 21 through the third communication hole 22, and the liquid and / or gas above the upper limiting plate 21 can also enter the space below the upper limiting plate 21 through the third communication hole 22.

[0090] The third communication hole arranged on the upper limiting plate can make the refrigerant liquid and / or gas below the upper limiting plate enter the space above the upper limiting plate through the third communication hole, and the refrigerant liquid and / or gas above the upper limiting plate can also enter the space below the upper limiting plate through the third communication hole, so that the refrigerant liquid can enter the space above the upper limiting plate when the liquid level rises, and the refrigerant liquid can enter the space below the upper limiting plate when the liquid level falls.

[0091] In some embodiments,

[0092] The upper limiting plate 21 is a porous plate, and the third communication hole 22 is a plurality of third communication holes 22, which are distributed on the upper limiting plate 21 in intervals.

[0093] The upper limiting plate of the present application is preferably a multi-hole plate, i.e. the insertion of the upper connecting rod into one of the third communication holes does not affect the flow of refrigerant fluid from the other third communication holes, ensuring the normal and effective flow of refrigerant fluid from the upper part to the lower part or vice versa of the upper limiting plate.

[0094] The inner cylinder of the liquid storage tank of the present application is preferably horizontally fixed with a low single-hole plate (lower limiting plate 18) and a high multi-hole plate (upper limiting plate 21), which are preferably sealed and fixed to the wall of the inner cylinder by welding, and the single-hole plate and the multi-hole plate are provided with flow-through holes (second communication holes 19) located on the same vertical line in the middle position, and the multi-hole plate further has at least one other flow-through hole (third communication hole 22), which is preferably as close as possible to the edge of the multi-hole plate, i.e. as close as possible to the wall of the inner cylinder (to prevent being blocked by the floating plug after being floated up), so the multi-hole plate has at least two third communication holes 22.

[0095] The bottom end surface of the low single-hole plate of the present application is higher than the first communication hole 9 on the side wall of the bottom of the inner cylinder; the high multi-hole plate is higher than the low single-hole plate and preferably ensures that the two are in a horizontal and parallel spaced state;

[0096] In some embodiments,

[0097] The upper end of the floating component 8 is further connected to an upper connecting rod 23, which is inserted into the third communication hole 22 and can move up and down along the third communication hole 22, and the outer peripheral cross-sectional area of the upper connecting rod 23 is smaller than the cross-sectional area of the third communication hole 22.

[0098] The present application further provides an upper connecting rod structure, which is inserted into the third communication hole and can guide and limit the upper end of the floating component, so that the upper end of the floating component can continuously and effectively move in the vertical direction, avoiding horizontal or inclined movement, and the cross-sectional area of the upper connecting rod is smaller than that of the third communication hole, which can ensure the normal and smooth movement of the upper connecting rod in the third communication hole.

[0099] In some embodiments,

[0100] The floating component 8 is a float, comprising an upper structure 24 and a lower structure 25, the lower end of the upper structure 24 is connected with the upper end of the lower structure 25, the upper structure 24 is a conical structure, the lower structure 25 is a cylindrical structure, when the upper connecting rod 23 and the lower connecting rod 20 are simultaneously provided, the upper end of the upper structure 24 is connected with the lower end of the upper connecting rod 23, the outer peripheral cross-sectional area of the upper end of the upper structure 24 is equal to the outer peripheral cross-sectional area of the lower end of the upper connecting rod 23, the lower end of the lower structure 25 is connected with the upper end of the lower connecting rod 20, and the outer peripheral cross-sectional area of the lower end of the lower structure 25 is greater than the outer peripheral cross-sectional area of the upper end of the lower connecting rod 20.

[0101] This is the preferred structure of the floating component of the present application, which is a float structure comprising an upper structure and a lower structure, the upper structure is preferably a cone, the upper end of which is connected with the lower end of the upper connecting rod, and the outer peripheral cross-sectional areas of the two are preferably equal, the upper end conical surface of the upper structure can guide the refrigerant fluid (including liquid and / or gas) flowing from top to bottom to move downward, so as not to deposit on the upper end surface of the floating component, and the lower structure is preferably a cylinder, the lower end of which is connected with the upper end of the lower connecting rod, and the cross-sectional area of the lower structure is greater than the upper end cross-sectional area of the lower connecting rod, so that when the floating component moves downward to the lower limit plate, the large-area lower end surface can effectively block the second communication hole on the lower limit plate, realizing the function of liquid passage and gas blocking.

[0102] The present application further preferably projects in the vertical plane, the upper structure is triangular, and the lower structure is rectangular.

[0103] The upper and lower ends of the float inside the liquid storage tank are also connected with thin rod-shaped components (the upper connecting rod 23 and the lower connecting rod 20), and the middle float is a large cross-section cylindrical structure; the thin rod components at the upper and lower ends of the float are respectively inserted into the flow-through holes in the middle of the multi-hole plate and the single-hole plate, so that the float is clamped between the multi-hole plate and the single-hole plate and can freely float up or down while being unable to be taken out of the single-hole plate and / or the multi-hole plate.

[0104] The lower end surface of the float is preferably a horizontal surface, and when the float floats against the lower end surface of the multi-hole plate, the upper end surface of the float cannot completely block the third communication hole at the edge of the multi-hole plate, that is, the multi-hole plate of the present application can ensure that the communication state of the upper and lower ends thereof is realized under any condition and cannot be closed and blocked.

[0105] The upper end surface of the float of the present application includes but is not limited to a horizontal surface, a conical surface, etc.; the horizontal cross-section of the float includes but is not limited to a circular shape, a rectangular shape, a rhombic shape, etc.

[0106] The horizontal sectional area of the thin rod part of the lower end of the float is preferably smaller than the horizontal area of the flow-through hole in the single-hole plate, and the horizontal sectional area of the thin rod part of the upper end of the float is smaller than the horizontal area of the flow-through hole in the multi-hole plate, so that when the float rises to the point that the horizontal plane of the lower end of the large sectional column structure of the float is away from the upper end surface of the single-hole plate, the refrigerant liquid can flow up and down through the flow-through hole of the single-hole plate, and thus when the float rises away from the single-hole plate, the uppermost space of the inner cylinder can be connected to the space of the outer cylinder in turn through the flow-through hole of the multi-hole plate, the flow-through hole of the single-hole plate, and the communication hole in the bottom sidewall of the inner cylinder (as shown in Figure 4 The isolation state of the uppermost space of the inner cylinder and the space of the outer cylinder is as shown in Figure 3 The float is lowered to abut against the upper end surface of the single-hole plate.

[0107] In some embodiments,

[0108] The floating part 8 has a central axis, the axes of the upper connecting rod 23 and the lower connecting rod 20 coincide with the central axis, and the axes of the upper structure 24 and the lower structure 25 also coincide with the central axis.

[0109] By setting the axes of the upper connecting rod, the lower connecting rod, the upper structure and the lower structure of the floating part to be along the direction of the central axis, i.e., the axes of the four coincide, the present application can ensure that they move up and down integrally in the vertical direction, and even if they rotate, they will not move horizontally or tilt, ensuring reliable and stable floating of the float and achieving the effect of liquid passage and gas blocking.

[0110] In some embodiments,

[0111] The evaporator 5 includes a gas collecting pipe 104 at the outlet end of the evaporator 5, and the other end of the balance pipe 103 is connected to the inner bottom end of the gas collecting pipe 104.

[0112] By connecting the other end of the balance pipe to the inner bottom end of the gas collecting pipe at the outlet end of the evaporator, the present application can guide the refrigerant liquid at the bottom of the gas collecting pipe that has not been evaporated out, and directly guide the refrigerant liquid at the bottom of the gas collecting pipe of the evaporator in the fluorine pump refrigeration mode back to the liquid storage tank to participate in system circulation as soon as possible, instead of entering the gas pipeline, thereby solving the problems of storage and release of the refrigerant liquid at the outlet of the evaporator that has not been evaporated, and effectively solving the problems of system design optimization of the flow path and flow of the refrigerant liquid.

[0113] The present application adds a new type of liquid storage tank in the fluorine pump compression refrigeration system, which is designed as a double-cylinder structure, the inner cylinder space and the outer cylinder space are only connected near the bottom of the first communication hole, the inner cylinder is spaced apart from the horizontal low single-hole plate (lower limit plate) and the horizontal high multi-hole plate (upper limit plate) and both are higher than the first communication hole, a float is arranged between the two hole plates and is limited between the two hole plates; the top of the inner cylinder is connected to the bottom of the gas collecting pipe of the evaporator, and a one-way valve is arranged on the connecting pipeline to limit the fluid to flow only from the evaporator to the inner cylinder of the liquid storage tank.

[0114] The beneficial effects of the present application: by utilizing the top pressure change of the inner cylinder of the liquid storage tank in the compression refrigeration mode and the fluorine pump refrigeration mode, the optimal refrigerant circulation amount required in the two operation modes is effectively adjusted, without increasing the control hardware and control software, by utilizing the change of system pressure and the change of float force to realize automatic balance adjustment to control the change of refrigerant liquid storage state in the liquid storage tank, so that the inner cylinder of the liquid storage tank becomes a variable containing space for refrigerant liquid, and the refrigerant liquid level height of the outer cylinder of the liquid storage tank in the fluorine pump refrigeration mode is higher, thereby ensuring that the fluorine pump has sufficient liquid suction height to reduce the probability of cavitation phenomenon, the system has high reliability, low cost, no special control adjustment, and the liquid level in the liquid storage tank has automatic balance adjustment function in different operation modes.

[0115] The present application solves the following technical problems:

[0116] 1) The problem of cavitation in the fluorine pump mode;

[0117] 2) The problem of refrigerant redundancy caused by the difference in the required refrigerant filling amount in different operation modes of the fluorine pump compression refrigeration system, and the problem of controlling the liquid level in the liquid storage tank;

[0118] 3) The problem of storage and release of the refrigerant liquid that has not been evaporated at the outlet of the evaporator, and the problem of optimizing the system design of the flow path and flow of these refrigerant liquids.

[0119] In order to solve the problem 2 in the background art, as shown in Figure 2 , the preferred embodiment of the present application is that the inlet of the one-way valve C is connected to the bottom of the gas collecting pipe of the evaporator (i.e. the balance pipe is connected to the bottom of the gas collecting pipe of the evaporator), so that the refrigerant liquid accumulated at the bottom of the gas collecting pipe can be smoothly discharged in the fluorine pump refrigeration mode and directly returned to the liquid storage tank to participate in the fluorine pump refrigeration cycle again (i.e. Figure 2 is Figure 1 one of the preferred embodiments), or part of the refrigerant fluid is introduced from the bottom of the gas collecting pipe to fill the upper space of the inner cylinder of the liquid storage tank, so as to force the refrigerant liquid in the inner cylinder space of the liquid storage tank to transfer to the outer cylinder space, and ensure that the float is lowered to abut on the single-hole plate to prevent the refrigerant gas from entering the outer cylinder space (such as Figure 1 orFigure 3

[0120] In some embodiments,

[0121] The compressor 1, the condenser 3, a liquid inlet pipe 101 and a liquid outlet pipe 102 are further included. One end of the liquid inlet pipe 101 is in communication with the condenser 3 and the other end is in communication with the inner top end of the outer cylinder 6 of the liquid storage tank 2, so as to guide the refrigerant in the condenser 3 after heat exchange into the liquid storage tank 2. One end of the liquid outlet pipe 102 is in communication with the inner bottom end of the outer cylinder 6 of the liquid storage tank 2 and the other end is in communication with one end of the fluorine pump 10.

[0122] This is a further preferred structure of the present application. The liquid inlet pipe is in communication with the top end of the outer cylinder, which can guide the refrigerant in the condenser after heat exchange into the outer cylinder of the liquid storage tank. The liquid outlet pipe is in communication with the inner bottom end of the outer cylinder, which can guide the refrigerant (preferably refrigerant liquid) in the outer cylinder out of the fluorine pump. The inner cylinder is used to guide the refrigerant liquid below the outer cylinder out of the inner cylinder, especially to increase the pressure at the top end of the inner cylinder in the fluorine pump refrigeration mode, so as to increase the liquid amount and the liquid height of the outer cylinder, and to ensure that the liquid height is sufficient in the fluorine pump mode to avoid the phenomenon of cavitation. In the compression mode, the liquid level height of the inner and outer cylinders is almost equal, which can automatically adjust the height of the liquid level of the outer cylinder according to different modes. The greater the frequency of the compressor in the compression mode, the higher the pressure at the liquid inlet pipe, and the lower the liquid level in the inner and outer cylinders. The liquid storage amount can be automatically adjusted according to different modes and the frequency of the compressor, which solves the problem of refrigerant redundancy caused by the difference in the amount of refrigerant to be filled, and solves the problem of control of the liquid level in the liquid storage tank.

[0123] The liquid outlet pipe 102 of the present application is preferably arranged at the bottom of the liquid storage tank. The liquid inlet pipe 101 is preferably arranged at the top of the outer cylinder space of the liquid storage tank 2 and / or at the bottom of the liquid storage tank.

[0124] In some embodiments,

[0125] ​Also included are a first pipeline 201, a second pipeline 202, a third pipeline 203, a fourth pipeline 204, a fifth pipeline 205, a throttle valve 4, a one-way valve A11, a one-way valve B15, and an oil separator 13. One end of the fluorine pump 10 is connected to one end of the evaporator 5 through the first pipeline 201, the throttle valve 4 is arranged on the first pipeline 201, one end of the second pipeline 202 is connected to the liquid outlet pipe 102, and the other end is connected to the first pipeline 201 at a position between the fluorine pump 10 and the throttle valve 4. The one-way valve A11 is arranged on the second pipeline 202 to allow fluid to flow only from the liquid outlet pipe 102 to the first pipeline 201. The other end of the evaporator 5 is connected to the third pipeline 203, the third pipeline 203 is connected to the suction end of the compressor 1 through the fourth pipeline 204, and the third pipeline 203 is also connected to the discharge end of the compressor 1 through the fifth pipeline 205. The one-way valve B15 is arranged on the fifth pipeline 205 to allow refrigerant fluid to flow only from the suction end to the discharge end of the compressor 1. The oil separator 13 is arranged between the discharge end of the compressor 1 and the condenser 3.

[0126] This is a further preferred structure of the refrigeration system of the present application, i.e., the one-way valve A is the pipeline through which the refrigerant flows in the compression refrigeration mode, and the one-way valve B is the pipeline through which the refrigerant flows in the fluorine pump mode. The one-way valve A effectively ensures that the refrigerant at the outlet end of the fluorine pump does not directly return to the inlet end of the fluorine pump, and the one-way valve B effectively ensures that the refrigerant at the outlet end of the compressor does not directly return to the inlet end of the compressor.

[0127] The present application adds a new type of liquid storage tank to the fluorine pump compression refrigeration system. The liquid storage tank is designed as a double-cylinder structure with an inner cylinder and an outer cylinder. The inner cylinder space is connected to the outer cylinder space only near the bottom connection. A horizontal low-position single-hole plate (lower limiting plate) and a horizontal high-position multi-hole plate (upper limiting plate) are arranged in the inner cylinder and are higher than the first communication hole (to ensure the normal floating of the float and the function of liquid passage and gas blocking). A float is arranged between the two hole plates and is limited between the two hole plates. The top of the inner cylinder is connected to the bottom of the gas collection pipe of the evaporator, and a one-way valve is arranged on the connecting pipeline to limit the fluid to flow only from the evaporator to the inner cylinder of the liquid storage tank.

[0128] By the one-way valve between the evaporator and the liquid storage tank, in the compression refrigeration mode, the one-way valve is in the reverse high-pressure cut-off state, the float in the liquid storage tank rises under the action of liquid buoyancy, the inner cylinder liquid level of the liquid storage tank rises, so that more refrigerant liquid can be stored to meet the less refrigerant circulating amount required in the compression refrigeration mode; in the fluorine pump refrigeration mode, the one-way valve is in the forward high-pressure flow state, the refrigerant fluid at the bottom of the gas collecting pipe fills into the inner cylinder of the liquid storage tank to force the refrigerant liquid to flow to the outer cylinder from the flow-through hole of the single-hole plate, so that the float descends and blocks the flow-through hole of the single-hole plate, so as to meet the more refrigerant circulating amount required in the fluorine pump refrigeration mode.

[0129] As can be known from the above, the liquid level self-balancing adjustment function of the liquid storage tank can be realized to meet the better refrigerant circulating amount in different modes, and the refrigerant liquid at the bottom of the evaporator gas collecting pipe in the fluorine pump refrigeration mode can be directly guided back to the liquid storage tank to participate in system circulation without entering the gas pipeline.

[0130] As shown in Figure 1 and Figure 2 , the fluorine pump compression refrigeration system is sequentially connected by a compressor 1, a condenser 3, a liquid storage tank 2, a fluorine pump 10, a throttling valve 4 and an evaporator 5;

[0131] The fluorine pump compression refrigeration system further comprises a one-way valve A11, the liquid outlet pipe 102 of the liquid storage tank 2 is connected to the inlet of the fluorine pump 10 and the inlet of the one-way valve A11, the outlet of the one-way valve A11 is connected between the outlet of the fluorine pump 10 and the inlet of the throttling valve 4, and the flow direction of the one-way valve A11 is only allowed to be directed from the liquid outlet pipe 102 of the liquid storage tank 2 to the inlet of the throttling valve 4.

[0132] The fluorine pump compression refrigeration system further comprises a one-way valve B15, the one-way valve B15 is connected in parallel to bypass the compressor, the inlet and the outlet of the one-way valve B15 are connected to the suction port and the exhaust port of the compressor 1 respectively, and the flow direction of the one-way valve B15 is only allowed to be directed from the inlet of the compressor 1 to the outlet of the compressor 1.

[0133] The fluorine pump compression refrigeration system further comprises an oil separator 13 and a capillary tube 16 for oil return, the oil separator 13 is connected between the exhaust port of the compressor 1 and the inlet of the condenser 3, the air inlet of the oil separator 13 is connected to the exhaust port of the compressor 1, the air outlet of the oil separator 13 is connected to the inlet of the condenser 3, and the capillary tube 16 is connected between the oil outlet of the oil separator 13 and the suction port of the compressor 1.

[0134] In some embodiments,

[0135] The other end of the balance pipe 103 is communicated to the third pipeline 203 or the fifth pipeline 205; or the evaporator 5 comprises a gas collecting pipe 104 located at the outlet end of the evaporator 5, and the other end of the balance pipe 103 is communicated to the inner bottom end of the gas collecting pipe 104, and the inner top end of the gas collecting pipe 104 is communicated with the third pipeline 203.

[0136] This is the preferred connection position and connection mode of the balance pipe of the present application. The other end of the balance pipe is preferably communicated to the third pipeline or the fifth pipeline, which can effectively introduce the fluid at the outlet end of the evaporator to the top of the inner cylinder, or the other end of the balance pipe is communicated to the inner bottom end of the gas collecting pipe, which can guide the refrigerant liquid at the bottom of the gas collecting pipe, which has not been evaporated, out as soon as possible, and directly guide the refrigerant liquid at the bottom of the gas collecting pipe of the evaporator in the fluorine pump refrigeration mode back to the liquid storage tank to participate in the system circulation, instead of entering the gas pipeline, thereby solving the problems of storage and release of the refrigerant liquid at the outlet end of the evaporator which has not been evaporated, effectively solving the problems of flow path and system design optimization of the refrigerant liquid, and the inner top end of the gas collecting pipe is communicated with the third pipeline, which can guide the refrigerant fluid after evaporation out of the third pipeline to the suction port of the compressor or into the condenser, thereby ensuring that the suction of the compressor does not carry liquid.

[0137] For the convenience of understanding and description, Figure 1 The state of the liquid storage tank in the fluorine pump refrigeration mode is shown (also refer to Figure 3 ), Figure 2 The state of the liquid storage tank in the compression refrigeration mode is shown (also refer to Figure 4 ), and the working principle of the fluorine pump compression refrigeration system, the circulating flow path of the refrigeration system, and the working state of the components are described as follows:

[0138] A) As shown in Figure 1 , the main flow path of the refrigerant in the fluorine pump refrigeration mode: fluorine pump → throttling valve → evaporator → one-way valve B → oil separator → condenser → liquid storage tank → fluorine pump.

[0139] Description:

[0140] a1) Part of the refrigerant at the outlet end of the evaporator also enters the oil separator through the capillary tube and then enters the condenser, that is, this flow path is in parallel with the flow path of the one-way valve B, but the refrigerant flow at the one-way valve B is larger, and the refrigerant flow in the flow path of the capillary tube can be ignored;

[0141] a2) When the fluorine pump is working, the outlet pressure is higher than the inlet pressure, that is, at this time, the one-way valve A is in a reverse high-pressure cut-off state and does not flow, that is, the one-way valve A can prevent the refrigerant liquid at the outlet of the fluorine pump from directly returning to the inlet of the fluorine pump;

[0142] a3) The fluorine pump outlet pressure is the highest point of the system pressure, and the fluorine pump inlet pressure is the lowest point of the system pressure, and the pressure gradually decreases in the flow direction of the refrigerant. Because the pressure at the outlet of the evaporator is higher than the pressure at the top of the liquid storage tank, the check valve C is in a positive high-pressure flow state at this time, so part of the refrigerant at the outlet of the evaporator will flow into the inner cylinder of the liquid storage tank from the check valve C. If liquid flows through the check valve C into the inner cylinder space of the liquid storage tank, when the inflowing refrigerant liquid is sufficient, the float will rise, and at this time the refrigerant liquid stored at the upper part of the inner cylinder will flow into the outer cylinder space from the flow-through hole of the single-hole plate. When the refrigerant liquid at the upper part of the inner cylinder is insufficient or even all refrigerant gas, the buoyancy of the float is insufficient to make the float drop until the flow-through hole of the single-hole plate is blocked, so the refrigerant gas at the upper part of the inner cylinder cannot enter the outer cylinder. Therefore, the float in the liquid storage tank has an automatic balancing and adjusting effect in the fluorine pump refrigeration mode. Since the inner cylinder space is mostly refrigerant gas, the amount of refrigerant liquid stored in the liquid storage tank will be less, that is, the circulating amount of refrigerant participating in the system operation will be more, thereby meeting the optimal refrigerant circulating amount requirement of the fluorine pump refrigeration mode. Because the liquid storage tank at this time basically only relies on the outer cylinder to participate in the refrigerant circulation, the height of the refrigerant liquid level in the outer cylinder will be larger, which meets the larger suction height required for safe operation of the fluorine pump, thereby reducing the probability of occurrence of the cavitation phenomenon of the fluorine pump, and the fluorine pump operates more safely and reliably.

[0143] B) As shown in Figure 2 , the main refrigerant flow path of the compression refrigeration mode: compressor → oil separator → condenser → liquid storage tank → check valve A → throttling valve → evaporator → compressor.

[0144] Explanation:

[0145] b1) The lubricating oil separated in the oil separator returns to the compressor suction port through the capillary tube under the action of the pressure difference between high pressure and low pressure. Sometimes there will be a small amount of high-pressure refrigerant gas returning to the compressor suction port from the capillary tube, but it can basically be ignored;

[0146] b2) Part of the refrigerant liquid from the liquid outlet pipe of the liquid storage tank will also flow through the impeller gap of the fluorine pump, that is, the check valve A and the fluorine pump are in parallel flow at this time, but the refrigerant liquid flow at the check valve A is larger, and the refrigerant liquid flow from the fluorine pump can be ignored;

[0147] b3) the compressor discharge pressure is the highest pressure in the system, the compressor suction pressure is the lowest pressure in the system, the pressure gradually decreases along the flow direction of the refrigerant, the inlet of the throttling valve is high pressure and the outlet is low pressure. Because the outlet of the check valve C is connected to the high pressure liquid tank, and the inlet of the check valve C is connected to the low pressure evaporator header, the check valve C is in the reverse high pressure cut-off non-flow state at this time, so the refrigerant liquid in the outer cylinder of the liquid tank can enter the floating plug to float, the refrigerant liquid in the outer cylinder enters the upper space of the inner cylinder in turn through the communication hole on the side wall of the bottom of the inner cylinder, the flow hole of the single hole plate and the flow hole of the multi-hole plate, so the refrigerant liquid level height of the inner cylinder and the outer cylinder is consistent (U-shaped tube communication device principle), so that the liquid tank can store more refrigerant liquid in the compression refrigeration mode, that is, the refrigerant circulating amount participating in the system operation will be less, thereby meeting the best refrigerant circulating amount demand of the compression refrigeration mode.

[0148] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A refrigeration system with a refrigerant redundancy adjustment function, characterized in that: The system comprises a fluorine pump (10), a liquid storage tank (2), an evaporator (5) and a balance pipe (103), the liquid storage tank (2) comprises an outer cylinder (6) and an inner cylinder (7), the inner cylinder (7) is located at the inner periphery of the outer cylinder (6), and a first communication hole (9) is arranged on the cylinder wall of the inner cylinder (7) to enable the interior of the inner cylinder (7) to communicate with the interior of the outer cylinder (6), the fluorine pump (10) is communicated between the interior of the outer cylinder (6) and the evaporator (5), one end of the balance pipe (103) is communicated to the interior upper end of the inner cylinder (7), the other end of the balance pipe (103) is communicated to the outlet end of the evaporator (5), and in the fluorine pump mode, the balance pipe (103) can introduce fluid from the outlet end of the evaporator (5) to the interior of the inner cylinder (7) to enable at least part of the liquid in the inner cylinder (7) to be pressed into the outer cylinder (6) through the first communication hole (9) to increase the liquid level height in the outer cylinder (6). The system further comprises a condenser (3) and a liquid inlet pipe (101), one end of the liquid inlet pipe (101) is communicated with the condenser (3), the other end is communicated with the interior top end of the outer cylinder (6) of the liquid storage tank (2) to enable the heat-exchanged refrigerant in the condenser (3) to be introduced into the liquid storage tank (2).

2. The refrigeration system with refrigerant redundancy adjustment function according to claim 1, characterized in that: A one-way valve C (12) is arranged on the balance pipe (103), and the one-way valve C (12) only allows fluid to flow from the outlet end of the evaporator (5) to the inner cylinder (7) in the balance pipe (103).

3. The refrigeration system with refrigerant redundancy adjustment function according to claim 1, characterized in that: The system further comprises a floating component (8), the floating component (8) is arranged in the interior of the inner cylinder (7), and the floating component (8) floats in the liquid in the inner cylinder (7) to rise or fall integrally with the liquid level height, a lower limit position plate (18) is arranged below the floating component (8), a second communication hole (19) is further arranged on the lower limit position plate (18), the second communication hole (19) penetrates the upper and lower end faces of the lower limit position plate (18), the liquid below the lower limit position plate (18) can enter above the lower limit position plate (18) through the second communication hole (19) and float the floating component (8) up, and when the liquid height above the lower limit position plate (18) falls to the height of the lower limit position plate (18), the floating component (8) falls to the second communication hole (19) and blocks the second communication hole (19).

4. The refrigeration system with refrigerant redundancy adjustment function according to claim 3, characterized in that: The position of the first communication hole (9) is lower than the height of the lower limit position plate (18); the second communication hole (19) and the floating component (8) are arranged opposite to each other in the vertical direction, and the lower end face area of the floating component (8) is greater than the cross-sectional area of the second communication hole (19). ​ 5. The refrigeration system with refrigerant redundancy adjustment function according to claim 4, characterized in that: The lower limit plate (18) is fixedly arranged on the inner wall of the inner cylinder (7), the outer peripheral wall of the lower limit plate (18) is sealingly fixed with the inner peripheral wall of the inner cylinder (7), the lower limit plate (18) can limit the downward movement of the floating component (8), and the lower limit plate (18) is a single-hole plate, that is, the number of the second communication holes (19) is one.

6. The refrigeration system with refrigerant redundancy adjustment function according to claim 3, characterized in that: The lower end of the floating component (8) is further connected with a lower connecting rod (20), the lower connecting rod (20) is arranged in the second communication hole (19) and can move up and down along the second communication hole (19), the outer peripheral cross-sectional area of the lower connecting rod (20) is smaller than the cross-sectional area of the second communication hole (19), and the outer peripheral cross-sectional area of the lower connecting rod (20) is smaller than the area of the lower end surface of the floating component (8).

7. The refrigeration system with refrigerant redundancy adjustment function according to any one of claims 3-6, characterized in that: An upper limit plate (21) is further arranged above the floating component (8), and the upper limit plate (21) is fixedly arranged on the inner wall of the inner cylinder (7) and can limit the upward movement of the floating component (8).

8. The refrigeration system with refrigerant redundancy adjustment function according to claim 7, characterized in that: The upper limit plate (21) is provided with a third communication hole (22), the third communication hole (22) penetrates the upper end surface and the lower end surface of the upper limit plate (21) to communicate the space above the upper limit plate (21) with the space below the upper limit plate (21), so that the liquid and / or gas below the upper limit plate (21) can enter the space above the upper limit plate (21) through the third communication hole (22), and the liquid and / or gas above the upper limit plate (21) can also enter the space below the upper limit plate (21) through the third communication hole (22).

9. The refrigeration system with refrigerant redundancy adjustment function according to claim 8, characterized in that: The upper limit plate (21) is a multi-hole plate, and the third communication hole (22) is a plurality of third communication holes (22) which are distributed on the upper limit plate (21) at intervals.

10. The refrigeration system with refrigerant redundancy adjustment function according to claim 8, characterized in that: The upper end of the floating component (8) is further connected with an upper connecting rod (23), the upper connecting rod (23) is arranged in the third communication hole (22) and can move up and down along the third communication hole (22), and the outer peripheral cross-sectional area of the upper connecting rod (23) is smaller than the cross-sectional area of the third communication hole (22).

11. The refrigeration system with refrigerant redundancy adjustment function according to claim 10, characterized in that: The floating component (8) is a floating plug, comprising an upper structure (24) and a lower structure (25), the lower end of the upper structure (24) is connected to the upper end of the lower structure (25), the upper structure (24) is a cone structure, and the lower structure (25) is a columnar structure. When both an upper connecting rod (23) and a lower connecting rod (20) are provided, the upper end of the upper structure (24) is connected to the lower end of the upper connecting rod (23), and the outer peripheral cross-sectional area of ​​the upper end of the upper structure (24) is equal to the outer peripheral cross-sectional area of ​​the lower end of the upper connecting rod (23). The lower end of the lower structure (25) is connected to the upper end of the lower connecting rod (20), and the outer peripheral cross-sectional area of ​​the lower end of the lower structure (25) is larger than the outer peripheral cross-sectional area of ​​the upper end of the lower connecting rod (20).

12. The refrigeration system with a refrigerant redundancy adjustment function according to claim 11, characterized in that: The floating component (8) has a central axis, the axes of the upper connecting rod (23) and the lower connecting rod (20) both coincide with the central axis, and the axes of the upper structure (24) and the lower structure (25) also coincide with the central axis.

13. The refrigeration system with a refrigerant redundancy adjustment function according to claim 1, characterized in that: The evaporator (5) comprises a gas collecting pipe (104), the gas collecting pipe (104) is located at the outlet end of the evaporator (5), and the other end of the balance pipe (103) is connected to the inner bottom end of the gas collecting pipe (104).

14. The refrigeration system with a refrigerant redundancy adjustment function according to claim 1, characterized in that: It also includes a compressor (1) and a liquid outlet pipe (102), one end of the liquid outlet pipe (102) is connected to the inner bottom end of the outer cylinder (6) of the liquid storage tank (2), and the other end is connected to one end of the fluorine pump (10).

15. The refrigeration system with a refrigerant redundancy adjustment function according to claim 14, characterized in that: Further comprising a first pipeline (201), a second pipeline (202), a third pipeline (203), a fourth pipeline (204), a fifth pipeline (205), a throttle valve (4), a one-way valve A (11), a one-way valve B (15) and an oil separator (13), one end of the fluorine pump (10) is communicated to one end of the evaporator (5) through the first pipeline (201), the throttle valve (4) is arranged on the first pipeline (201), one end of the second pipeline (202) is communicated to the liquid outlet pipe (102), the other end is communicated to a position between the fluorine pump (10) and the throttle valve (4) on the first pipeline (201), and the one-way valve A (11) allowing fluid to flow only from the liquid outlet pipe (102) to the first pipeline (201) is arranged on the second pipeline (202); the other end of the evaporator (5) is communicated to the third pipeline (203), the third pipeline (203) is communicated to the suction end of the compressor (1) through the fourth pipeline (204), the third pipeline (203) is also communicated to the exhaust end of the compressor (1) through the fifth pipeline (205), the one-way valve B (15) allowing refrigerant fluid to flow only from the suction end to the exhaust end of the compressor (1) is arranged on the fifth pipeline (205), and the oil separator (13) is arranged between the exhaust end of the compressor (1) and the condenser (3).

16. The refrigeration system with a refrigerant redundancy adjustment function according to claim 15, characterized in that: the other end of the balance pipe (103) is communicated to the third pipeline (203) or the fifth pipeline (205); or the evaporator (5) comprises a gas collecting pipe (104), the gas collecting pipe (104) is located at the outlet end of the evaporator (5), the other end of the balance pipe (103) is communicated to the inner bottom end of the gas collecting pipe (104), and the inner top end of the gas collecting pipe (104) is communicated to the third pipeline (203).

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