Low-voltage anti-freezing protection switch device for heat pump

Abstract

The utility model discloses a low-pressure anti-freezing protection switch device for a heat pump, which comprises a low-pressure pressure sensor, a controller and a flow adjusting unit, and the low-pressure pressure sensor is arranged in an inlet of a second heat exchanger and used for detecting the pressure of a refrigerant at the inlet of the second heat exchanger. The flow adjusting unit is arranged on a pipeline between the expansion valve and the second heat exchanger, and the low-pressure pressure sensor and the flow adjusting unit are electrically connected with the controller. According to the low-pressure anti-freezing protection switch device for the heat pump, the low-pressure pressure sensor is arranged at the inlet of the second heat exchanger of the heat pump system, so that the flow of a refrigerant entering the second heat exchanger is reduced when the evaporation pressure of the refrigerant is reduced, heat absorbed from a water path is reduced, water in the water path is prevented from being frozen, and the service life of the heat pump is prolonged. And the heat pump system is protected from being damaged due to water freezing.

Description

Technical Field

[0001] The utility model relates to the technical field of low-temperature heat pumps, and more specifically, the utility model relates to a low-pressure anti-freezing protection switch device for a heat pump. Background Art

[0002] As an energy-saving technology, heat pumps have been widely regarded by countries around the world. Air-source heat pumps can extract rich low-grade energy from the ambient atmosphere, are convenient to use, and have low installation costs. Therefore, air-source heat pumps have become the most widely used type among various heat pump types.

[0003] The heat pump system realizes the transfer of heat through the phase change cycle of the refrigerant. A heat pump is a device that transfers the thermal energy of a low-temperature heat source to a high-temperature heat source. It is usually used for refrigeration and heating. By using the principle of the reverse Carnot cycle and the switching of a four-way valve, the heat pump system can realize the functions of summer refrigeration and winter heating.

[0004] The working principle of the heat pump system for refrigeration is as Figure 1 shown. The refrigerant flows in the direction indicated by the arrow in the figure. When the refrigerant passes through the compressor 100, the compressor 100 compresses the low-temperature and low-pressure gaseous refrigerant into a high-temperature and high-pressure gas. When the high-temperature and high-pressure gas passes through the first heat exchanger 101, since the condensation point of the refrigerant gas in the high-pressure state is higher than the normal temperature, the high-temperature and high-pressure refrigerant gas releases heat in the first heat exchanger 101, and the refrigerant condenses into a high-pressure liquid. The high-pressure liquid refrigerant passes through the expansion valve 102, and the pressure and temperature decrease, becoming a low-temperature and low-pressure wet steam. The low-temperature and low-pressure wet steam absorbs heat in the second heat exchanger 103 and evaporates into a gas, completing a cycle. In the second heat exchanger 103, the water in the water circuit 104 releases heat, and the water temperature decreases to become low-temperature water. After the low-temperature water enters the room, it exchanges heat with the indoor air through a fan to cool the room. By setting a four-way valve 105 in the heat pump system and changing the flow direction of the refrigerant, the heat pump system can realize heating in winter and cooling in summer.

[0005] Patent document CN117760126A discloses an anti-freezing control method and system for a heat pump system, which obtains the real-time ambient temperature of the environment where the heat pump system is located, and determines whether to turn on the anti-freezing mode of the heat pump system according to the real-time ambient temperature; when it is determined to turn on the anti-freezing mode of the heat pump system, the outlet water temperature and the inlet water temperature of the heat pump system are collected, and an anti-freezing control instruction for the heat pump system is set according to the outlet water temperature and the inlet water temperature; based on the anti-freezing control instruction, anti-freezing control is performed on the heat pump system; the anti-freezing duration of the heat pump system is obtained, and it is determined whether the heat pump system meets the warning condition according to the anti-freezing duration. When the heat pump system meets the warning condition, a warning reminder is sent in real time.

[0006] When the air source low-temperature heat pump system is in refrigeration, it is necessary to prevent the heat pump system from freezing to prevent the water in the water circuit from freezing and damaging the heat pump system. The existing anti-freezing of the heat pump system only detects the outlet temperature of the heat pump system, gives an early warning reminder when the outlet temperature is too low, and then closes the water circuit or the compressor, which will cause a long reaction time and make the anti-freezing fail, resulting in damage to the heat pump system.

[0007] Therefore, it is necessary to propose a heat dissipation structure for an immersion liquid-cooled data center to solve the problems existing in the prior art. Utility Model Content

[0008] In the utility model content part, a series of simplified concepts are introduced, which will be further described in detail in the specific implementation part. The utility model content part of the present utility model does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the protection scope of the claimed technical solution.

[0009] To solve the above problems, the present utility model provides a low-pressure anti-freezing protection switch device for a heat pump, which includes a low-pressure pressure sensor, a controller and a flow regulation unit. The low-pressure pressure sensor is arranged inside the inlet of the second heat exchanger to detect the pressure of the refrigerant at the inlet of the second heat exchanger. The flow regulation unit is arranged on the pipeline between the expansion valve and the second heat exchanger. The low-pressure pressure sensor and the flow regulation unit are respectively electrically connected to the controller.

[0010] Preferably, the flow regulation unit includes a housing, and the housing includes a cylindrical barrel and conical barrels symmetrically arranged at both ends of the barrel. A valve body is movably arranged inside the housing.

[0011] Preferably, the flow regulation unit further includes a motor fixedly arranged on the outer wall of the barrel. The motor is electrically connected to the controller. The power output shaft of the motor penetrates the outer wall of the barrel and enters the barrel. A transmission shaft is fixedly connected to the power output shaft of the motor. A first bevel gear is fixedly arranged at the end of the transmission shaft away from the motor;

[0012] A support ring is arranged on the inner wall of the barrel. The support ring is coaxially arranged with the barrel. A threaded rod is slidably arranged inside the support ring. The valve body is fixedly arranged at one end of the threaded rod. A second bevel gear is rotatably connected to the support ring. The second bevel gear is meshed with the first bevel gear. A threaded hole is opened at the center of the second bevel gear, and the threaded hole is threadedly connected to the threaded rod.

[0013] Preferably, a spoke plate fixedly connected to the inner wall of the barrel is fixedly arranged on the outer circumference of the support ring, and at least two spoke plates are arranged in an array along the circumferential direction of the support ring.

[0014] Preferably, a first plane parallel to the axis of the threaded rod is provided on the circumferential surface of the threaded rod, and a second plane is provided on the inner circumferential surface of the support ring, and the second plane is in contact with the first plane.

[0015] Preferably, a connection hole is opened on the side of the threaded hole of the second bevel gear close to the support ring, a circular first card slot is opened on the inner wall of the connection hole along the circumferential direction, and a second card slot is opened on the outer circumferential wall of the support ring corresponding to the first card slot along the circumferential direction, and a snap ring is clamped in the first card slot and the second card slot.

[0016] Preferably, the valve body is a conical cylinder, the taper of the valve body is the same as that of the conical cylinder, and the concave side of the valve body is fixedly connected to the end of the threaded rod.

[0017] Preferably, two support rings are arranged at intervals along the axis direction of the cylinder body.

[0018] Preferably, the valve body is made of a polymer material.

[0019] Preferably, the controller is fixedly arranged on the top of the housing.

[0020] Compared with the prior art, the present utility model has at least the following beneficial effects:

[0021] For the low-pressure anti-freezing protection switch device for a heat pump of the present utility model, by arranging a low-pressure pressure sensor at the inlet of the second heat exchanger of the heat pump system, when the evaporation pressure of the refrigerant decreases, the flow rate of the refrigerant entering the second heat exchanger is reduced, the heat absorbed from the water circuit is reduced, the water in the water circuit is prevented from freezing, and the heat pump system is protected from being damaged due to water freezing.

[0022] For the low-pressure anti-freezing protection switch device for a heat pump of the present utility model, other advantages, objectives and features of the present utility model will be partially reflected by the following description, and partially will be understood by those skilled in the art through the research and practice of the present utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings are used to provide a further understanding of the present utility model, and constitute a part of the specification. Together with the embodiments of the present utility model, they are used to explain the present utility model, and do not constitute a limitation to the present utility model. In the drawings:

[0024] Figure 1 is the refrigeration schematic diagram of the low-temperature heat pump system disclosed by the present utility model;

[0025] Figure 2 is the structural schematic diagram of the low-pressure anti-freezing protection switch device for a heat pump disclosed by the present utility model;

[0026] Figure 3 is the structural schematic diagram of the flow rate regulating unit disclosed by the present utility model;

[0027] Figure 4 It is a schematic structural view of the right sectional view of the cylinder body disclosed by the present utility model;

[0028] Figure 5 It is a schematic structural view of the sectional view of the threaded rod disclosed by the present utility model;

[0029] Figure 6 It is a schematic structural view of the installation of the second bevel gear disclosed by the present utility model;

[0030] Figure 7 is Figure 6 an enlarged view of part A in Specific embodiments

[0031] The following further elaborates on the present utility model in conjunction with the attached drawings and embodiments, so that those skilled in the art can implement it with reference to the text of the specification.

[0032] It should be understood that the terms such as "having", "comprising", and "including" used herein do not exclude the presence or addition of one or more other elements or their combinations.

[0033] As Figures 1-7 shown, a low-pressure anti-freezing protection switch device for a heat pump includes a low-pressure pressure sensor 1, a controller 2, and a flow regulation unit 3. The low-pressure pressure sensor 1 is arranged inside the inlet of the second heat exchanger 103 to detect the pressure of the refrigerant at the inlet of the second heat exchanger 103. The flow regulation unit 3 is arranged on the pipeline between the expansion valve 102 and the second heat exchanger 103. The low-pressure pressure sensor 1 and the flow regulation unit 3 are respectively electrically connected to the controller 2.

[0034] Furthermore, the flow regulation unit 3 includes a housing 4. The housing 4 includes a cylindrical cylinder body 5 and conical cylinders 6 symmetrically arranged at both ends of the cylinder body 5. A valve body 7 is movably arranged inside the housing 4.

[0035] Furthermore, the flow regulation unit 3 further includes a motor 8 fixedly arranged on the outer wall of the cylinder body 5. The motor 8 is electrically connected to the controller 2. The power output shaft of the motor 8 penetrates the outer wall of the cylinder body 5 and enters the cylinder body 5. A transmission shaft 9 is fixedly connected to the power output shaft of the motor 8. A first bevel gear 10 is fixedly arranged at the end of the transmission shaft 9 away from the motor;

[0036] A support ring 11 is arranged on the inner wall of the cylinder body 5. The support ring 11 is coaxially arranged with the cylinder body 5. A threaded rod 12 is slidably arranged inside the support ring 11. The valve body 7 is fixedly arranged at one end of the threaded rod 12. A second bevel gear 13 is rotatably connected to the support ring 11. The second bevel gear 13 is meshed with the first bevel gear 10. A threaded hole is opened at the center of the second bevel gear 13. The threaded hole is threadedly connected to the threaded rod 12.

[0037] Further, on the outer circumference of the support ring 11, a spoke plate 14 fixedly connected to the inner wall of the cylinder body 5 is fixedly arranged, and at least two spoke plates 14 are arranged in an array along the circumferential direction of the support ring 11.

[0038] Further, a first plane 15 parallel to the axis of the threaded rod 12 is arranged on the circumferential surface of the threaded rod 12, and a second plane 16 is arranged on the inner circumferential surface of the support ring 11, and the second plane 16 is in contact with the first plane 15.

[0039] Further, a connection hole 17 is opened on the side of the threaded hole of the second bevel gear 13 close to the support ring 11. An annular first card slot 18 is opened on the inner wall of the connection hole 17 along the circumferential direction. A second card slot 19 is opened on the outer circumferential wall of the support ring 11 corresponding to the first card slot 18 along the circumferential direction. A snap ring 20 is clamped in the first card slot 18 and the second card slot 19.

[0040] Further, the valve body 7 is a conical cylinder, the taper of the valve body 7 is the same as that of the conical cylinder 6, and the concave side of the valve body 7 is fixedly connected to the end of the threaded rod 12.

[0041] Further, two support rings 11 are arranged at intervals along the axial direction of the cylinder body 5.

[0042] Further, the valve body 7 is made of a polymer material.

[0043] Further, the controller 2 is fixedly arranged on the top of the housing 4.

[0044] The working principle of the above technical solution:

[0045] The heat pump system includes a first heat exchanger 101, a second heat exchanger 103, an expansion valve 102, and a compressor 100. The liquid inlet of the compressor 100 is communicated with the outlet of the second heat exchanger 103 through a four-way valve 105. The liquid outlet of the compressor 100 is communicated with the inlet of the first heat exchanger 101 through a four-way valve. The liquid inlet of the expansion valve 102 is communicated with the outlet of the first heat exchanger 101. The liquid outlet of the expansion valve 102 is communicated with the inlet of the heat exchanger 103. In the refrigeration mode, the refrigerant circulates in the direction shown by the arrow in Figure 1 The refrigeration principle has been described in the background technology and will not be elaborated here.

[0046] The low-pressure anti-freezing protection switch device for the heat pump is arranged between the liquid outlet of the expansion valve 102 and the inlet of the second heat exchanger 103 and is communicated with the liquid outlet of the expansion valve 102 and the inlet of the second heat exchanger 103.

[0047] When the refrigerant is in a gaseous state and absorbs heat and evaporates in the second heat exchanger 103, the evaporation temperature of the refrigerant is related to the pressure in the second heat exchanger 103. The following table shows the relationship between the evaporation temperature and pressure of common refrigerants. When the pressure in the second heat exchanger 103 is too low, the evaporation temperature of the refrigerant is relatively low, lower than zero degrees Celsius, which will cause the water in the water circuit 104 to freeze, resulting in the abnormal operation of the heat pump system and damage to the components of the heat pump system.

[0048] Comparison of Absolute Pressure and Evaporation Temperature of Common Refrigerants

[0049]

[0050] To prevent the water in the water circuit of the heat pump system from freezing due to the too low evaporation temperature of the refrigerant, a low-pressure pressure sensor 1 is fixedly installed at the inlet of the second heat exchanger 103. When it is detected that the pressure in the second heat exchanger 103 drops to the set pressure, the controller 2 controls the flow rate of the refrigerant in the flow rate adjustment unit 3 according to the pressure detected by the low-pressure pressure sensor 1, reducing the amount of refrigerant entering the second heat exchanger 103, thereby reducing the heat exchange of the water in the water circuit 104 in the heat pump system and preventing the water from freezing.

[0051] The controller 2 controls the flow rate of the flow rate adjustment unit 3 according to the pressure detected by the low-pressure pressure sensor 1. When the low-pressure pressure sensor 1 is lower than the set pressure value, the voltage signal transmitted from the low-pressure pressure sensor 1 to the controller 2 is set with three gear intervals in the controller 2. The flow rate of the refrigerant in the flow rate adjustment unit 3 is also divided into three intervals and respectively corresponds to the three gear intervals of the voltage signal of the low-pressure pressure sensor 1 received in the controller 2. The controller 2 controls the flow rate of the flow rate adjustment unit 3 according to the interval where the voltage signal transmitted by the low-pressure pressure sensor is located. The low-pressure pressure sensor 1 can select a general pressure sensor suitable for the power of the heat pump system on the market. The controller 2 differentiates the voltage signal transmitted by the low-pressure pressure sensor according to the selected pressure sensor.

[0052] The motor 8 of the flow regulating unit 3 starts and stops according to the control of the controller, adjusts the distance between the regulating valve body 7 and the conical cylinder 6 of the housing 4, so as to achieve the purpose of regulating the flow rate of the refrigerant passing through the housing 4. The conical cylinders 6 on both sides are respectively communicated with the expansion valve 102 and the second heat exchanger 103. The diameter of the conical outer circumference of the valve body 7 is larger than the diameter of the central hole of the conical cylinder 6 and smaller than the diameter of the cylinder body 5. The controller 2 controls the rotation of the motor 8, drives the second bevel gear 13 to rotate through the transmission shaft 9 and the first bevel gear 10. Since the threaded hole in the center of the second bevel gear 13 is threadedly connected with the threaded rod 12, and the first plane 15 on the threaded rod 12 and the second plane 16 on the inner circumferential surface of the support ring 11 limit the rotation of the threaded rod, the threaded rod can only move axially, thereby driving the valve body 7 to move axially along the cylinder body 5. The change in the distance between the valve body 7 and the conical cylinder 6 on the side close to the valve body 7 can adjust the flow rate of the refrigerant passing through the flow regulating unit. The three-stage flow rate can be set according to the distance between the valve body 7 and the conical cylinder 6, and can be set according to the differences in the heat pump system in actual applications, which will not be elaborated here.

[0053] The central hole of the conical cylinder 6 on the left side is communicated with the liquid outlet of the expansion valve 102 through a pipeline, and the central hole of the conical cylinder 6 on the right side is communicated with the inlet of the second heat exchanger 103 through a pipeline.

[0054] When the pressure detected by the low-pressure pressure sensor 1 is less than the minimum pressure value set in the controller 2, the controller 2 controls the motor to rotate, so that the valve body 7 abuts against the conical cylinder 6, making the flow rate of the refrigerant passing through the flow regulating unit zero. At the same time, the controller 2 controls the compressor to cut off the power supply and stop working. The compressor is electrically connected to the controller.

[0055] The beneficial effects of the above technical solutions:

[0056] For the low-pressure anti-freezing protection switch device for a heat pump described in the present invention, by setting a low-pressure pressure sensor at the inlet of the second heat exchanger of the heat pump system, when the evaporation pressure of the refrigerant decreases, the flow rate of the refrigerant entering the second heat exchanger is reduced, the heat absorbed from the water circuit is reduced, the water in the water circuit is prevented from freezing, and the heat pump system is protected from being damaged due to water freezing.

[0057] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0058] In the present utility model, unless otherwise clearly specified and defined, terms such as "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection, or communication with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0059] Although the embodiments of the present utility model have been disclosed as above, it is not limited to the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present utility model. For those familiar with the field, additional modifications can be easily made. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present utility model is not limited to the specific details and the examples shown and described herein.

Claims

1. A low-voltage antifreeze protection switch device for a heat pump, characterized in that: The invention comprises a low-pressure pressure sensor (1), a controller (2) and a flow regulating unit (3); the low-pressure pressure sensor (1) is arranged at the inlet of the second heat exchanger (103) for detecting the pressure of the refrigerant at the inlet of the second heat exchanger (103); the flow regulating unit (3) is arranged on the pipeline between the expansion valve (102) and the second heat exchanger (103); the low-pressure pressure sensor (1) and the flow regulating unit (3) are respectively electrically connected to the controller (2).

2. The low-voltage antifreeze protection switch device for heat pump according to claim 1, characterized in that: The flow regulating unit (3) comprises a housing (4), the housing (4) comprising a cylindrical body (5) and conical cylinders (6) symmetrically arranged at both ends of the body (5), and a valve body (7) is movably arranged in the housing (4).

3. The low-voltage antifreeze protection switch device for heat pump according to claim 2, characterized in that: The flow regulating unit (3) further comprises a motor (8) fixedly arranged on the outer wall of the cylinder (5), the motor (8) being electrically connected to the controller (2), a power output shaft of the motor (8) penetrating the outer wall of the cylinder (5) and entering the cylinder (5), a transmission shaft (9) being fixedly connected to the power output shaft of the motor (8), and a first bevel gear (10) being fixedly arranged at one end of the transmission shaft (9) away from the motor; A support ring (11) is arranged on the inner wall of the cylinder (5), the support ring (11) and the cylinder (5) are arranged coaxially, a threaded rod (12) is slidably arranged in the support ring (11), the valve body (7) is fixedly arranged on one end of the threaded rod (12), the support ring (11) is rotatably connected to the second bevel gear (13), the second bevel gear (13) is meshed with the first bevel gear (10), a threaded hole is arranged at the center of the second bevel gear (13), and the threaded hole is threadedly connected to the threaded rod (12).

4. The low-voltage antifreeze protection switch device for heat pump according to claim 3, characterized in that: A spoke plate (14) fixedly connected to the inner wall of the cylinder (5) is fixedly arranged on the outer circumference of the support ring (11), and at least two spoke plates (14) are arranged in an array along the circumferential direction of the support ring (11).

5. The low-voltage antifreeze protection switch device for heat pump according to claim 4, characterized in that: A first plane (15) parallel to the axis of the threaded rod (12) is arranged on the circumferential surface of the threaded rod (12), and a second plane (16) is arranged on the inner circumferential surface of the support ring (11), and the second plane (16) contacts the first plane (15).

6. The low-voltage antifreeze protection switch device for heat pump according to claim 5, characterized in that: A connecting hole (17) is provided on one side of the threaded hole of the second bevel gear (13) close to the support ring (11); a first annular clamping groove (18) is provided on the inner wall of the connecting hole (17) along the circumferential direction; a second clamping groove (19) is provided on the outer circumferential wall of the support ring (11) at a position corresponding to the first clamping groove (18) along the circumferential direction; and a clamping ring (20) is clamped in the first clamping groove (18) and the second clamping groove (19).

7. The low-voltage antifreeze protection switch device for a heat pump according to claim 6, characterized in that: The valve body (7) is in the shape of a cone-shaped cylinder. The taper of the valve body (7) is the same as that of the cone cylinder (6). The concave side of the valve body (7) is fixedly connected to the end of the threaded rod (12).

8. The low-voltage antifreeze protection switch device for a heat pump according to claim 6, characterized in that: Two support rings (11) are arranged at intervals along the axial direction of the cylinder (5).

9. The low-voltage antifreeze protection switch device for a heat pump according to claim 5, characterized in that: The valve body (7) is made of high molecular polymer material.

10. The low-voltage antifreeze protection switch device for heat pump according to claim 1, characterized in that: The controller (2) is fixedly arranged on the top of the housing (4).

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