Defrosting water anti-freezing and centralized discharging system

Abstract

The utility model relates to a defrosting water anti -freezing centralized drainage system, include: located water collecting tank at fin bottom, the bottom plate of water collecting tank is to single side inclination setting, and its bottom forms the drain outlet, a plurality of connecting in water collecting tank drain outlet's drain pipe, every drain pipe's other end is connected to main discharge pipe, main discharge pipe is to one end inclination setting, the outer wall of main discharge pipe is wound with the heat -tracing band, and the heat -tracing band surface is wrapped fixedly provided with the heat -preserving layer, the heat -tracing band is connected with control unit through cable, is used for controlling the start and pause of heat -tracing band, power, with heat -tracing band and control unit connection, is used for providing electric energy for heat -tracing band and control unit.

Description

Technical Field

[0001] This utility model relates to a low ambient temperature air source heat pump, specifically to a centralized defrosting water antifreeze discharge system. Background Technology

[0002] Low-ambient-temperature air-source heat pump units are widely used in heating systems in northern China. These units use finned heat exchangers as evaporators. During low-ambient-temperature operation, the refrigerant saturation temperature inside the finned evaporator heat exchange tubes will be below 0°C. Therefore, water vapor in the air will condense on the fins and solidify into frost. Consequently, low-ambient-temperature air-source heat pump units require defrosting when frost buildup is severe. Currently, most domestic manufacturers handle defrost water by direct venting. This causes defrost water to drip directly from the bottom of the finned evaporator onto the ground, resulting in ice formation, affecting the safety of maintenance personnel and the overall aesthetics of the demonstration project. Furthermore, the defrost water may freeze before dripping from the fins onto the ground, leading to ice buildup on the unit or ice accumulation at the bottom. This ice buildup requires manual cleaning; otherwise, it may damage unit components and cause the unit to shut down. Utility Model Content

[0003] To address the aforementioned problems, this utility model provides a centralized defrosting water antifreeze drainage system, comprising:

[0004] A water collection trough is located at the bottom of the fins, and the bottom plate of the water collection trough is inclined to one side, with a drain outlet formed at the bottom.

[0005] Multiple drain pipes are connected to the drain outlet of the water collection tank, and the other end of each drain pipe is connected to the main discharge pipe;

[0006] The main discharge pipe is inclined at one end;

[0007] The outer wall of the main discharge pipe is wrapped with a heat tracing cable, and a heat insulation layer is fixedly wrapped around the surface of the heat tracing cable.

[0008] The heat tracing cable is connected to the control unit via a cable, which is used to control the start and stop of the heat tracing cable;

[0009] A power supply, connected to the heat tracing cable and control unit, is used to provide electrical energy to the heat tracing cable and control unit.

[0010] Preferably, the diameter of the main discharge pipe is larger than the diameter of the drain pipe.

[0011] Preferably, the heat tracing cable is fixed by a stainless steel clamp, and the stainless steel clamp is provided with a pad to prevent damage to the heat tracing cable.

[0012] Preferably, the stainless steel tiger clamp is made of a rust-resistant material.

[0013] Preferably, the slope i of the main discharge pipe is not less than 1%.

[0014] Preferably, the outer surface of the heat tracing cable is provided with multiple protective insulation layers, and the rated operating power is not less than 30W / m.

[0015] Preferably, the control unit is a programmable controller, used to control the start of the heating tape and timed antifreeze operation for a preset time when the unit enters the defrosting phase.

[0016] Preferably, the system further includes a control AC contactor connected to the programmable controller and the heat tracing cable for controlling the on / off state of the heat tracing cable circuit.

[0017] By employing the above-mentioned technical means, it achieves the following beneficial effects:

[0018] This utility model provides a centralized defrost water antifreeze drainage system. By installing an inclined water collection trough and main discharge pipe at the bottom of the fins, along with a heating tape and insulation layer, it achieves centralized drainage and effective antifreeze protection of defrost water. The system utilizes gravity diversion and pipe slope design to ensure that defrost water flows rapidly to the designated outlet, preventing it from accumulating and freezing at the bottom of the unit or on the ground. This effectively prevents safety hazards such as slippery maintenance passages and obstructed equipment operation caused by ice accumulation, significantly improving the reliability of unit operation and the safety and cleanliness of the site environment. Furthermore, the entire drainage system uses standardized plastic pipes and conventional electrical components, resulting in a simple structure, low material cost, and convenient installation and maintenance, demonstrating good engineering applicability and economic efficiency.

[0019] Furthermore, this system employs a control unit for intelligent control of the heating cable, achieving automated operation. The heating cable automatically starts during unit defrosting and can perform antifreeze operation periodically in frost-free conditions, avoiding the energy waste associated with traditional continuous heating. In dry weather or when the unit has not been defrosted for an extended period, the heating cable can be shut down to achieve energy savings. This intelligent control strategy ensures both antifreeze effectiveness and improved energy efficiency. Attached Figure Description

[0020] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0021] Figure 1 A schematic diagram of a drainage pipe structure provided for an exemplary embodiment of this utility model;

[0022] Figure 2 A schematic diagram of a water collection tank structure provided for an exemplary embodiment of this utility model;

[0023] Figure 3 A schematic diagram of the fixing structure of the heat tracing cable inside the water tank provided in an exemplary embodiment of this utility model;

[0024] Figure 4 A schematic diagram of the arrangement of the heat tracing cable in the water tank provided in an exemplary embodiment of this utility model;

[0025] Figure 5 This is a schematic diagram of the water pipe external heat tracing cable winding method provided for an exemplary embodiment of the present invention. Detailed Implementation

[0026] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0027] This utility model provides a centralized defrosting water antifreeze drainage system, comprising: a water collection tank located at the bottom of the fins, the bottom plate of the water collection tank being inclined to one side, and a drain outlet forming at its bottom; multiple drain pipes connected to the drain outlet of the water collection tank, the other end of each drain pipe being connected to a main discharge pipe; the main discharge pipe being inclined to one end; a heat tracing cable wrapped around the outer wall of the main discharge pipe, and an insulation layer being fixedly wrapped around the surface of the heat tracing cable; the heat tracing cable being connected to a control unit via a cable for controlling the start and stop of the heat tracing cable; and a power supply connected to the heat tracing cable and the control unit for providing electrical energy to the heat tracing cable and the control unit.

[0028] Specifically, such as Figure 1 and Figure 2 As shown, the water collection trough located at the bottom of the fins is a sheet metal water collection trough. A schematic diagram of the connection structure of the PP plastic drain pipe connected to the sheet metal water collection trough is shown. The main drain pipe is not placed horizontally, but has a certain slope, for example, i ≥ 1%. This is to facilitate the centralized discharge of defrosting water into the engineering drain pipe.

[0029] In practice, a sheet metal water collection trough is first installed at the bottom of the finned evaporator of the air source heat pump unit. The bottom plate of the trough is sloped at an angle of i=1% to guide the defrost water to a drain outlet on one side. For example, the sheet metal water collection trough is made of 1.5mm thick stainless steel plate with a rust-proof treatment to ensure it will not rust or corrode during long-term outdoor use. The size of the water collection trough is customized according to the size of the finned evaporator to ensure it can fully collect the defrost water.

[0030] The diameter of the main discharge pipe is larger than the diameter of the drain pipe.

[0031] Specifically, a φ50 drain pipe is installed at the drain outlet of the sheet metal water collection tank. This drain pipe is made of low-temperature resistant and corrosion-resistant PP material, and its length is determined according to actual installation requirements. Each φ50 drain pipe is connected to a φ100 plastic PP pipe to collect and guide the defrost water to the pre-reserved outlet of the drain pipe. The main discharge pipe is a φ100 plastic PP pipe, installed at a slope of i=1% to ensure smooth flow of defrost water and prevent accumulation in the pipe.

[0032] like Figure 3 and Figure 4 As shown in the figure, a cross-sectional view of the sheet metal water collection tank is presented, including the sheet metal water collection tank 00 at the bottom of the finned evaporator, the heating cable 10, the rubber pad 20, and the stainless steel clamp 30. The heating cable 10 is laid at the bottom of the sheet metal water collection tank 00, and the rubber pad 20 is placed on top of the heating cable 10. The stainless steel clamp 30 is rotated and tightened, causing the pressure plate to press the heating cable 10 firmly. The use of the rubber pad 20 in this application prevents the metal pressure plate of the stainless steel clamp 30 from directly contacting the insulation layer of the heating cable, thus protecting the insulation layer.

[0033] Specifically, an insulation layer is installed on the surface of the PP pipe. This layer uses a 20mm thick closed-cell rubber-plastic insulation material, wrapped with aluminum foil to prevent ice formation inside the pipe. Simultaneously, an explosion-proof reinforced heat tracing cable 10 is wrapped around the outer wall of the PP pipe. The heat tracing cable 10 has a multi-layered protective insulation structure, is not easily damaged, has a power rating of 30W / m or higher, and is suitable for outdoor applications. The heat tracing cable 10 is wound evenly at 300mm intervals to ensure that the defrosting water inside the pipe does not freeze.

[0034] In this embodiment, placing the heating cable on the bottom plate of the sheet metal water collection tank effectively prevents defrost water from freezing inside the tank. The heating cable is placed in close contact with the bottom plate of the tank, further ensuring that the defrost water inside the tank will not freeze. Furthermore, the heating cable is secured using stainless steel clamps, which are made of stainless steel with a rust-proof surface, suitable for outdoor environments, and easy to disassemble and maintain. A plastic gasket is placed between the clamps and the heating cable to prevent the clamps from damaging the insulation layer of the heating cable.

[0035] Furthermore, the connection section of the heating cable includes a tail end, a two-way valve, a three-way valve, and a power supply junction box. The power supply junction box contains electrical connection terminals, and a cable connects the heating cable to an AC contactor that controls the on / off state of the heating cable circuit. The AC contactor is connected to the control unit via a control circuit. For example, the control unit uses a Siemens S7-200 series PLC, which automatically controls the start and stop of the heating cable according to the unit's operating status. A thermal relay is installed in the circuit for leakage and overload protection, ensuring safe system operation. The heating cable and control unit are connected to a power supply to provide electrical energy to both the heating cable and the control unit.

[0036] The control logic of this system is as follows: when the unit enters defrosting mode, the programmable controller automatically starts the heating cable, which operates for a preset time (e.g., 2 hours) to prevent freezing. If the unit does not defrost for an extended period in dry weather, the heating cable will not operate, achieving energy-saving operation. The system provided in this application uses PLC automatic control, requiring no manual intervention and making operation more intelligent.

[0037] The following section further elaborates on this solution in conjunction with the equipment installation process. First, the sheet metal water collection tank is fixed to the bottom of the finned evaporator of the unit, ensuring that the slope i of the tank's bottom plate is not less than 1%. Then, a φ50 plastic PP pipe is connected to the drain outlet of the water collection tank, followed by an connection to a φ100 plastic PP pipe, with the φ100 pipe set at a slope of i=1%. A heating tape is then wrapped around the outer wall of the φ100 plastic PP pipe, maintaining a 300mm spacing during wrapping to ensure uniform heating. The heating tape is connected to the power supply junction box via a tail end, a T-junction, and a T-junction, with the junction box installed in an easily accessible maintenance location.

[0038] For the cable tracing system, the cable is placed on the sheet metal water collection tank base plate and then secured with stainless steel clamps. Plastic gaskets are placed between the clamps and the cable to prevent damage to the insulation layer. All electrical connections are made in accordance with electrical specifications to ensure safety and reliability.

[0039] The equipment provided by this invention can operate in ambient temperatures as low as -25℃. Defrosting water can be smoothly discharged into water supply and drainage pipes without ice accumulation or blockage. Defrosting water will not drip onto the ground causing ice formation, nor will it accumulate at the bottom of the unit, effectively increasing the safety of maintenance access and improving the reliability and aesthetics of the unit. The heating tape is automatically controlled by a PLC, achieving intelligent anti-freeze functionality. If the unit is not defrosted for an extended period in dry weather, the heating tape will not operate, resulting in more energy-efficient operation.

[0040] This system uses low-value materials, resulting in lower costs, easier manufacturing, and simpler installation. It is suitable for widespread application in various low-ambient-temperature air-source heat pump units. All components of the system have undergone rigorous testing to ensure long-term stable operation under harsh environmental conditions, demonstrating its high application value.

[0041] Other embodiments of this application will readily conceive of by those skilled in the art upon consideration of the specification and practice of the technical solutions disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0042] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A centralized discharge system for defrosting water to prevent freezing, characterized in that, include: A water collection trough is located at the bottom of the fins, and the bottom plate of the water collection trough is inclined to one side, with a drain outlet formed at the bottom. Multiple drain pipes are connected to the drain outlet of the water collection tank, and the other end of each drain pipe is connected to the main discharge pipe; The main discharge pipe is inclined at one end; The outer wall of the main discharge pipe is wrapped with a heat tracing cable, and a heat insulation layer is fixedly wrapped around the surface of the heat tracing cable. The heat tracing cable is connected to the control unit via a cable, which is used to control the start and stop of the heat tracing cable; A power supply, connected to the heat tracing cable and control unit, is used to provide electrical energy to the heat tracing cable and control unit.

2. The defrosting water antifreeze centralized discharge system according to claim 1, characterized in that, The diameter of the main discharge pipe is larger than the diameter of the drain pipe.

3. The defrosting water antifreeze centralized discharge system according to claim 1, characterized in that, The heat tracing cable is fixed by a stainless steel clamp, and the stainless steel clamp is provided with a pad to prevent damage to the heat tracing cable.

4. The defrosting water antifreeze centralized discharge system according to claim 3, characterized in that, The stainless steel tiger clamp is made of rust-resistant material.

5. The defrosting water antifreeze centralized discharge system according to claim 1, characterized in that, The slope i of the main discharge pipe shall not be less than 1%.

6. The defrosting water antifreeze centralized discharge system according to claim 1, characterized in that, The outer surface of the heat tracing cable is provided with multiple protective insulation layers, and the rated operating power is not less than 30W / m.

7. The defrosting water antifreeze centralized discharge system according to claim 1, characterized in that, The control unit is a programmable controller, used to control the start of the heating tape and timed antifreeze operation for a preset time when the unit enters the defrosting phase.

8. The defrosting water antifreeze centralized discharge system according to claim 7, characterized in that, The system also includes a control AC contactor connected to the programmable controller and the heat tracing cable for controlling the on / off state of the heat tracing cable circuit.

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