An external water circulation fish tank heater

Abstract

The present invention discloses an external water circulation fish tank heater, comprising a heating barrel, on which a water inlet pipe, a water outlet pipe and a control panel are arranged, the outer wall of the water inlet pipe is connected with a pumping pipe and a water delivery pipe located at the downstream side of the pumping pipe, one end of the pumping pipe and the water delivery pipe are respectively connected with a one-way pumping piston pump and a one-way water delivery piston pump, one end of the one-way pumping piston pump and the one-way water delivery piston pump are respectively connected with a drainage pipe and a water inlet pipe, and an expansion tube is serially connected to the drainage pipe. In the present invention, by installing a one-way pumping piston pump and a one-way water delivery piston pump located at the downstream side of the one-way pumping piston pump on the water inlet pipe of the heating barrel, the one-way pumping piston pump pumps out raw water, the one-way water delivery piston pump delivers new water into the water inlet pipe, the low-temperature new water is mixed with the raw water and enters the heating barrel, and the heated mixed water flows back into the fish tank, realizing the constant temperature water exchange function, which can effectively avoid the formation of temperature difference water area.

Description

Technical Field

[0001] The invention relates to the technical field of fish tank heating equipment, in particular to an external water circulation fish tank heater. Background Art

[0002] Aquariums are used to raise various aquatic animals or plants. Since tropical fish are born in tropical waters, they have high requirements for the living environment such as water temperature and oxygen content. If the water for raising tropical fish does not contain enough oxygen or the temperature does not meet the standard, it will cause the tropical fish to get sick or even die. The water in the aquarium or fish tank is naturally at a low temperature, which is not suitable for the survival temperature of tropical fish. To solve this problem, the commonly used solution is to add a heating device to the fish tank. The heating device can increase the water temperature in the fish tank to meet the water temperature requirements.

[0003] Fish tank heating devices are divided into built-in heating and external heating according to the installation location. Built-in heating is to install the heating device inside the fish tank. Its advantage is that it does not occupy external space. External heating is to install the heater outside the fish tank. Its advantage is that it does not occupy the space inside the fish tank, avoids fish collision, and is easy to maintain.

[0004] At present, the utility model with publication number CN218073097U proposes an external water circulation fish tank heater, which belongs to the technical field of heating devices for fish tanks. By installing a clamping device on the heater shell, not only the heater as a whole can be installed on fish tanks of different thicknesses, but also the installation structure between the heater and the side wall of the fish tank is stable and easy to disassemble.

[0005] However, the above-mentioned prior art still has the following deficiencies when used: 1. When changing the water in the fish tank, a water pump is usually used to deliver water to the fish tank alone. Since there is a temperature difference between the delivered new water and the original water in the fish tank, after the new water enters the fish tank, it is easy to form an area with a large temperature difference in the fish tank. When the temperature difference is large, it is easy to cause the ornamental fish to become diseased. Simply put, the existing heater does not have a constant temperature water changing function; 2. Moreover, the above-mentioned prior art has the defect of poor energy-saving effect. Specifically, when the fish tank is regularly changed in large quantities, it is necessary to increase the heating temperature of the heater to accelerate the heating of the new water, so as to stabilize the water temperature in the fish tank, which will lead to a greatly increased power consumption problem; 3. Fish feces are easily left in the external heating barrel. After the fish feces accumulate, it will affect the heat conduction effect of the heater in the heating barrel, and then affect the heating performance. Simply put, the existing external heating barrel does not have a filtering function.

[0006] Therefore, the present invention proposes an external water circulation fish tank heater. Summary of the invention

[0007] The purpose of the present invention is to provide an external water circulation fish tank heater in order to solve the problems mentioned in the background technology.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] An external water circulation fish tank heater comprises a heating barrel, wherein the heating barrel is provided with a water inlet pipe, a water outlet pipe and a control panel, the outer wall of the water inlet pipe is connected with a water pumping pipe and a water delivery pipe located at the downstream side of the water pumping pipe, one end of the water pumping pipe and the water delivery pipe are respectively connected with a one-way water pumping piston pump and a one-way water delivery piston pump, one end of the one-way water pumping piston pump and the one-way water delivery piston pump are respectively connected with a drainage pipe and a water inlet pipe, the drainage pipe is serially connected with an expansion pipe, the water inlet pipe passes through the inner cavity of the expansion pipe, and a driving mechanism for controlling the reciprocating motion of the one-way water pumping piston pump and the one-way water delivery piston pump is arranged outside the water inlet pipe.

[0010] As a further description of the above technical solution:

[0011] The outer cylinder wall of the one-way water supply piston pump is fixedly connected with a water supply one-way valve and a water inlet one-way valve, and the water supply one-way valve and the water inlet one-way valve are respectively connected to the water supply pipe and the water inlet pipe. The outer cylinder wall of the one-way water pumping piston pump is fixedly connected with a water pumping one-way valve and a water discharge one-way valve, and the water pumping one-way valve and the water discharge one-way valve are respectively connected to the water pumping pipe and the water discharge pipe.

[0012] As a further description of the above technical solution:

[0013] One side of the piston disk in the one-way water supply piston pump and the one-way water extraction piston pump is respectively fixedly connected to a water supply plug rod and a water extraction plug rod, each of which has one end extending to the outside of the outer cylinder. The water supply plug rod and the water extraction plug rod are arranged opposite to each other and coaxially, and the driving mechanism is arranged between the water supply plug rod and the water extraction plug rod.

[0014] As a further description of the above technical solution:

[0015] The driving mechanism includes a main shaft, a connecting rod and a control motor. The main shaft is rotatably connected to the water inlet pipe and a crank is welded to one end of the main shaft. A connecting rod shaft located at the free end is welded to one side of the crank. The connecting rod shaft is hingedly connected to the opposite ends of the water delivery plug rod and the water withdrawal plug rod through the connecting rod respectively. The control motor is fixedly connected to the water inlet pipe and its output shaft is fixedly connected to one end of the main shaft.

[0016] As a further description of the above technical solution:

[0017] A guide plate is welded to the free end of the connecting rod shaft, a slider is provided on one side of the guide plate and the sliding direction of the slider is perpendicular to and intersects with the axis of the main shaft, a screw rod for controlling the sliding of the slider is provided on the guide plate, a short-circuit shaft is welded to one side of the slider, one end of the connecting rod connected to the water delivery plug rod is rotatably connected to the short-circuit shaft, and one end of the connecting rod connected to the water pumping plug rod is rotatably connected to the connecting rod shaft.

[0018] As a further description of the above technical solution:

[0019] The screw rod is rotatably connected to one side of the guide plate and is screwed through and connected to the slider. A knob located at one end of the guide plate is welded to one end of the screw rod.

[0020] As a further description of the above technical solution:

[0021] The water inlet pipe is provided with a curved pipe portion located between the water suction pipe and the water delivery pipe, and a filter barrel is serially connected to the curved pipe portion.

[0022] As a further description of the above technical solution:

[0023] The filter barrel includes a barrel body, a rectangular support frame and a filter assembly. One end of the barrel body is open and the other end is a blind end. The outer wall of the barrel body is close to the blind end and is connected in series with the curved pipe portion. Sealing plates that are sealingly and slidingly matched with the inner wall of the barrel body are welded at both ends of the rectangular support frame. The filter assembly is detachably connected in the rectangular support frame.

[0024] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0025] 1. In the present invention, a one-way water pumping piston pump and a one-way water delivery piston pump located at the downstream side of the one-way water pumping piston pump are installed on the water inlet pipe of the heating barrel. The one-way water pumping piston pump draws out raw water, and the one-way water delivery piston pump delivers new water into the water inlet pipe. The low-temperature new water is mixed with the raw water and enters the heating barrel. After being heated, the mixed water flows back into the fish tank, thereby realizing the constant temperature water exchange function and effectively avoiding the formation of temperature difference water areas.

[0026] 2. In the present invention, by connecting an expansion tube in series to the drainage pipe, and then passing the water diversion pipe through the expansion tube, in the process of discharging the raw water from the discharge pipe, the heat of the raw water will be transferred to the new water in the water diversion pipe, so that the new water will be preheated and enter the heating barrel, thereby reducing the temperature set by the heater in the heating barrel during heating, which has the advantage of energy-saving heating.

[0027] 3. In the present invention, by connecting the filter barrel in series to the water inlet pipe, the nitrification system in the filter barrel is in a stable state and is not affected by water changes. It can also effectively prevent fish feces from entering the heating barrel and affecting the heating effect of the heating barrel.

[0028] 4. In the present invention, the filter barrel has the function of replacing the filter assembly without passing water. This arrangement can ensure that the water in the fish tank is in a continuous circulation state, thereby ensuring the oxygen content of the water.

[0029] 5. In the present invention, by providing a guide plate, a slider and a screw, the water delivery amount of the one-way water delivery piston pump in a reciprocating cycle can be adjusted, which is convenient for replenishing the evaporated water when the water body is replaced, so that the water level returns to the initial state. It is suitable for use in occasions where the water in the fish tank evaporates too quickly. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a structural schematic diagram of an external water circulation fish tank heater proposed by the present invention;

[0031] Figure 2 for Figure 1 The main view;

[0032] Figure 3 This is a structural schematic diagram of an external water circulation fish tank heater proposed by the present invention;

[0033] Figure 4 for Figure 1 The enlarged schematic diagram of the part "a" in the middle;

[0034] Figure 5 This is a schematic diagram of the structure of a one-way water delivery piston pump with adjustable water delivery volume for an external water circulation fish tank heater proposed by the present invention;

[0035] Figure 6 for Figure 5 Schematic diagram of the enlarged part “b” in the figure.

[0036] Legend:

[0037] 1. Heating barrel; 2. Water inlet pipe; 21. Bend pipe; 3. Water outlet pipe; 4. Pumping pipe; 5. Water delivery pipe; 6. One-way pumping piston pump; 61. Pumping check valve; 62. Drainage check valve; 63. Pumping plug rod; 7. One-way water delivery piston pump; 71. Water delivery check valve; 72. Water inlet check valve; 73. Water delivery plug rod; 8. Drain pipe; 81. Expansion pipe; 9. Water inlet pipe; 101. Driving mechanism; 101. Driving machine Structure; 1011, main shaft; 10111, crank; 101111, connecting rod shaft; 1012, connecting rod; 1013, control motor; 102, control panel; 103, guide plate; 104, slider; 1041, short-circuit shaft; 105, screw rod; 1051, knob; 106, filter barrel; 1061, barrel body; 1062, rectangular support frame; 10621, sealing plate; 1063, filter assembly. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Example 1

[0040] See also Figure 1-4 An external water circulation fish tank heater comprises a heating barrel 1, on which a water inlet pipe 2, a water outlet pipe 3 and a control panel 102 are arranged, a heater and a temperature sensor are installed in the inner cavity of the heating barrel 1, buttons and a display are arranged on the control panel 102, the temperature sensor displays the water temperature through the display, and the function of the button is to set the heating temperature. When in use, one end of the water inlet pipe 2 is connected to a water pump, the water pump is located in the fish tank, and then one end of the water outlet pipe 3 is placed in the fish tank away from the water pump to realize water circulation heating.

[0041] In this technical solution, a pumping pipe 4 and a water delivery pipe 5 located at the downstream side of the pumping pipe 4 are connected to the outer wall of the water inlet pipe 2. One ends of the pumping pipe 4 and the water delivery pipe 5 are respectively connected to a one-way pumping piston pump 6 and a one-way water delivery piston pump 7. The one-way pumping piston pump 6 is used to pump water outward from the water inlet pipe 2, and the one-way water delivery piston pump 7 is used to deliver water into the water inlet pipe 2. One ends of the one-way pumping piston pump 6 and the one-way water delivery piston pump 7 are respectively connected to a drain pipe 8 and a water inlet pipe 9. After the one-way pumping piston pump 6 pumps water through the pumping pipe 4, part of the original water in the fish tank is discharged outward through the drain pipe 8. The one-way water delivery piston pump 7 introduces new water through the water inlet pipe 9, and then delivers it to the drain pipe 8 through the water delivery pipe 5. The purpose of this setting is to achieve constant temperature water exchange to avoid excessive and rapid changes in water temperature during water exchange.

[0042] Specifically, the outer cylinder wall of the one-way water delivery piston pump 7 is fixedly connected with a water delivery one-way valve 71 and a water inlet one-way valve 72, and the water delivery one-way valve 71 and the water inlet one-way valve 72 are respectively connected to the water delivery pipe 5 and the water inlet pipe 9, so that a reciprocating cycle of the piston disc in the one-way water delivery piston pump 7 can achieve a single pumping and water delivery function. The outer cylinder wall of the one-way water pumping piston pump 6 is fixedly connected with a water pumping one-way valve 61 and a water discharge one-way valve 62, and the water pumping one-way valve 61 and the water discharge one-way valve 62 are respectively connected to the water pumping pipe 4 and the water discharge pipe 8, so that a reciprocating cycle of the piston disc in the one-way water pumping piston pump 6 can achieve a single pumping and water discharge function.

[0043] Furthermore, an expansion tube 81 is connected in series to the drain pipe 8, and the water inlet pipe 9 passes through the inner cavity of the expansion tube 81. The expansion tube 81 is a water temperature recovery tube for raw water from the fish tank. The raw water from the fish tank entering the expansion tube 81 will preheat the part of the water inlet pipe 9 located inside the expansion tube 81. A row of heat-conducting fins can be welded on the outer wall of the water inlet pipe 9. This arrangement can increase the heating speed of new water while reducing heat energy waste, and has the advantage of energy saving.

[0044] A driving mechanism 101 is provided on the outside of the water inlet pipe 2 for controlling the reciprocating motion of the one-way water pumping piston pump 6 and the one-way water delivery piston pump 7, wherein the portion of the water inlet pipe 2 connected to the driving mechanism 101, the water delivery pipe 5 and the water pumping pipe 4 is a hard pipe structure. After the driving mechanism 101 is started, the water inlet pipe 2 will continuously discharge raw water and continuously enter new water, so as to ensure that the total amount of water in the fish tank remains unchanged while the water temperature is kept at a constant temperature when changing the water.

[0045] As mentioned above, one side of the piston disk in the one-way water supply piston pump 7 and the one-way water pumping piston pump 6 is respectively fixedly connected to a water supply plug rod 73 and a water pumping plug rod 63, one end of which extends to the outside of the outer cylinder. The water supply plug rod 73 and the water pumping plug rod 63 are arranged opposite to each other and coaxially. The driving mechanism 101 is arranged between the water supply plug rod 73 and the water pumping plug rod 63. The driving mechanism 101 is used to control the axial reciprocating motion of the water supply plug rod 73 and the water pumping plug rod 63.

[0046] Specifically, see Figure 4 The driving mechanism 101 includes a main shaft 1011, a connecting rod 1012 and a control motor 1013. The main shaft 1011 is rotatably connected to the water inlet pipe 2 and a crank 10111 is welded at one end thereof, wherein a positioning plate can be welded to the outer wall of the water inlet pipe 2. The main shaft 1011 is rotatably connected to the positioning plate, and then a connecting rod shaft 101111 located at the free end is welded on one side of the crank 10111. The connecting rod shaft 101111 is hingedly connected to the opposite ends of the water delivery plug rod 73 and the water pumping plug rod 63 through the connecting rod 1012 respectively. When the main shaft 1011 rotates, it will drive the water delivery plug rod 73 and the water pumping plug rod 63 to axially reciprocate through the two connecting rods 1012. The control motor 1013 is fixedly connected to the water inlet pipe 2 and its output shaft is fixedly connected to one end of the main shaft 1011 . The control motor 1013 provides driving force for the rotation of the main shaft 1011 . The control motor 1013 is electrically connected to the circuit board in the control panel 102 .

[0047] In this embodiment, the water inlet pipe 2 is provided with a curved pipe portion 21 located between the water suction pipe 4 and the water delivery pipe 5, and the curved pipe portion 21 is connected in series with a filter barrel 106, which has the function of filtering the water in the fish tank. The purpose of this setting is to ensure that the nitrifying bacteria in the filter barrel 106 is in a constant temperature state, so that the nitrifying bacteria can be in the best active state.

[0048] For further information, see Figure 3 The filter barrel 106 includes a barrel body 1061, a rectangular support frame 1062 and a filter assembly 1063. The barrel body 1061 is a cylindrical structure, one end of the barrel body 1061 is open and the other end is a blind end. The outer peripheral wall of the barrel body 1061 is connected in series with the curved pipe portion 21 close to the blind end, so that the water flow in the water inlet pipe 2 will pass through the inner cavity of the barrel body 1061. Sealing plates 10621 that are sealed and slidably matched with the inner peripheral wall of the barrel body 1061 are welded at both ends of the rectangular support frame 1062. The sealing plate 10621 is disc-shaped, and a circle of sealing rubber pads are bonded to the outer periphery of the sealing plate 10621 to achieve sealing cooperation with the inner wall of the barrel body 1061, wherein the rectangular support frame 1062 is a positioning frame structure, and the filter assembly 1063 is detachably connected in the rectangular support frame 1062, specifically, the filter assembly 1063 and the inner cavity of the rectangular support frame 1062 are snap-connected. The filter component 1063 is a stacked composition of integrated filter cotton, activated carbon and nitrifying culture cotton. During filtering, the water in the water inlet pipe 2 will enter the barrel body 1061 and continue to flow after being filtered by the filter component 1063, and finally enter the heating barrel 1. It should be noted that the outer wall of the rectangular support frame 1062 is an arc-shaped structure and is in a sealed fit with the inner wall of the barrel body 1061. Specifically, a layer of rubber pad can be bonded to the outer arc wall of the rectangular support frame 1062. When the filter component 1063 needs to be replaced, just pull the rectangular support frame 1062 outward. During replacement, one of the sealing plates 10621 is moved out of the barrel body 1061, and the other sealing plate 10621 is close to the mouth of the barrel body 1061. The barrel body 1061 is in a blocked state at the mouth. At this time, a small amount of raw water from the fish tank will pass directly through the barrel body 1061. After replacing the filter component 1063, the rectangular support frame 1062 is reset to re-filter the circulating water. After the rectangular support frame 1062 is reset, the sealing plate 10621 is firmly connected to the barrel body 1061 using friction. This setting does not require water to be stopped to replace the filter component 1063, does not affect the oxygen supply in the water body, and is more convenient to replace the filter component 1063 and clean the dirt in the barrel body 1061. It should be noted that this setting can also effectively avoid the accumulation of residual fish excrement in the heating barrel 1 without affecting the heating effect.

[0049] Example 2

[0050] See also Figure 5 and Figure 6The structure in which a connecting rod shaft 101111 and two connecting rods 1012 are rotatably connected in Example 1 makes the discharge amount of raw water and the replenishment amount of new water in a fixed state. This arrangement is not conducive to adjusting the water change speed according to the season. That is to say, when the room temperature is high in summer, the water in the fish tank evaporates quickly. At this time, it is difficult to replenish water in the water change operation of Example 1, and it is difficult to achieve water level recovery. Therefore, the difference between this embodiment and Example 1 is that a guide plate 103 is welded to the free end of the connecting rod shaft 101111, a slider 104 is provided on one side of the guide plate 103, and the sliding direction of the slider 104 is perpendicular to and intersects with the axis of the main shaft 1011, and a screw rod 105 for controlling the sliding of the slider 104 is provided on the guide plate 103. Specifically, the screw rod 105 is rotatably connected to one side of the guide plate 103 and is screwed through and connected to the slider 104. A knob 1051 located at one end of the guide plate 103 is welded to one end of the screw rod 105. A short-circuited shaft 1041 is welded to one side of the slider 104. When the slider 104 slides, the distance between it and the main shaft 1011 will change. One end of the connecting rod 1012 connected to the water supply plug rod 73 is rotatably connected to the short-circuited shaft 1041, thereby adjusting the amount of water replenished into the water inlet pipe 2 during one cycle of the one-way water supply piston pump 7. One end of the connecting rod 1012 connected to the water pumping plug rod 63 is rotatably connected to the connecting rod shaft 101111. The amount of water pumped from the water inlet pipe 2 during one cycle of the one-way water pumping piston pump 6 is the same as that in Example 1.

[0051] Working principle: When in use, a mounting base is fixedly connected to the bottom of the heating barrel 1, and the heater is installed on the ground next to the fish tank through the mounting base. When part of the water in the fish tank needs to be replaced, one end of the water inlet pipe 9 is connected to the water storage bucket filled with new water through a hose, the drain pipe 8 is connected to the sewage bucket through a hose, and one end of the water inlet pipe 2 is connected to the water pump in the fish tank through a hose. When changing the water, start the control motor 1013. When the main shaft 1011 rotates, the crank 10111 drives the two connecting rods 1012 to move, and the water delivery plug rod 73 and the water pumping plug rod 63 will reciprocate axially. Part of the raw water in the water inlet pipe 2 will be pumped away through the water pumping pipe 4, and new water will be added to the water inlet pipe 2 from the water delivery pipe 5. After the new water and the raw water are mixed, the temperature will be reduced. The water with reduced water temperature enters the heating barrel 1 and is heated, and then flows back to the fish tank through the water outlet pipe 3. In this process, the water body can be heated while the water change function can be realized.

[0052] When summer comes, the room temperature is high and the water in the fish tank evaporates too quickly. At this time, it is necessary to control the rotation of the screw rod 105 to control the slider 104 to move away from the main shaft 1011. The movement range of the water supply plug rod 73 increases, and the water replenishment amount of the one-way water supply piston pump 7 is greater than the water pumping amount of the one-way water pumping piston pump 6. In this way, the water level can be reset while achieving constant temperature water exchange.

[0053] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An external water circulation fish tank heater, comprising a heating barrel (1), wherein the heating barrel (1) is provided with a water inlet pipe (2), a water outlet pipe (3) and a control panel (102), characterized in that: The outer wall of the water inlet pipe (2) is connected to a water extraction pipe (4) and a water delivery pipe (5) located at the downstream side of the water extraction pipe (4); one end of the water extraction pipe (4) and the water delivery pipe (5) are respectively connected to a one-way water extraction piston pump (6) and a one-way water delivery piston pump (7); one end of the one-way water extraction piston pump (6) and the one-way water delivery piston pump (7) are respectively connected to a drainage pipe (8) and a water inlet pipe (9); an expansion pipe (81) is connected in series to the drainage pipe (8); the water inlet pipe (9) passes through the inner cavity of the expansion pipe (81); and the inner cavity of the one-way water delivery piston pump (7) and the one-way water extraction piston pump (6) are connected to the expansion pipe (81). A water delivery plug rod (73) and a water pumping plug rod (63) are fixedly connected to one side of the plug disc, each of which has one end extending to the outside of the outer cylinder. The water delivery plug rod (73) and the water pumping plug rod (63) are arranged opposite to each other and coaxially. A driving mechanism (101) for controlling the reciprocating motion of a one-way water pumping piston pump (6) and a one-way water delivery piston pump (7) is arranged outside the water inlet pipe (2). The driving mechanism (101) is arranged between the water delivery plug rod (73) and the water pumping plug rod (63). The driving mechanism (101) comprises a main shaft (1011), a connecting rod (1012) and a control motor (1013). ), the main shaft (1011) is rotatably connected to the water inlet pipe (2) and a crank (10111) is welded to one end of the main shaft (10111), a connecting rod shaft (101111) located at the free end is welded to one side of the crank (10111), the connecting rod shaft (101111) is hingedly connected to the opposite ends of the water delivery plug rod (73) and the water withdrawal plug rod (63) through a connecting rod (1012), the control motor (1013) is fixedly connected to the water inlet pipe (2) and its output shaft is fixedly connected to one end of the main shaft (1011), the free end of the connecting rod shaft (101111) is welded to a guide plate (101111) 3), a slider (104) is provided on one side of the guide plate (103), and the sliding direction of the slider (104) is perpendicular to and intersects with the axis of the main shaft (1011), a screw rod (105) for controlling the sliding of the slider (104) is provided on the guide plate (103), a short-circuit shaft (1041) is welded on one side of the slider (104), one end of the connecting rod (1012) connected to the water delivery plug rod (73) is rotatably connected to the short-circuit shaft (1041), and one end of the connecting rod (1012) connected to the water pumping plug rod (63) is rotatably connected to the connecting rod shaft (101111).

2. The external water circulation fish tank heater according to claim 1, characterized in that: The outer cylinder wall of the one-way water delivery piston pump (7) is fixedly connected with a water delivery one-way valve (71) and a water inlet one-way valve (72), and the water delivery one-way valve (71) and the water inlet one-way valve (72) are respectively connected to the water delivery pipe (5) and the water inlet pipe (9); the outer cylinder wall of the one-way water extraction piston pump (6) is fixedly connected with a water extraction one-way valve (61) and a water discharge one-way valve (62), and the water extraction one-way valve (61) and the water discharge one-way valve (62) are respectively connected to the water extraction pipe (4) and the water discharge pipe (8).

3. The external water circulation fish tank heater according to claim 1, characterized in that: The screw rod (105) is rotatably connected to one side of the guide plate (103) and is screwed through and connected to the slider (104). One end of the screw rod (105) is welded with a knob (1051) located at one end of the guide plate (103).

4. The external water circulation fish tank heater according to claim 1, characterized in that: The water inlet pipe (2) is provided with a curved pipe portion (21) located between the water suction pipe (4) and the water delivery pipe (5), and a filter barrel (106) is serially connected to the curved pipe portion (21).

5. The external water circulation fish tank heater according to claim 4, characterized in that: The filter barrel (106) comprises a barrel body (1061), a rectangular support frame (1062) and a filter assembly (1063); one end of the barrel body (1061) is open and the other end is a blind end; the outer wall of the barrel body (1061) is connected in series with the curved pipe portion (21) close to the blind end; sealing plates (10621) that are sealingly and slidably matched with the inner wall of the barrel body (1061) are welded at both ends of the rectangular support frame (1062); and the filter assembly (1063) is detachably connected in the rectangular support frame (1062).

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