Passive dual liquid level controller based on float control

By utilizing a passive dual-level controller with a float and lever mechanism, automatic valve control in humid environments is achieved, solving the problems of low reliability and long stroke control of existing drain valves in humid environments, and realizing energy-saving and reliable valve control.

CN115539702BActive Publication Date: 2026-06-09HUNAN ZHENCHUANG ENVIRONMENTAL PROTECTION TECH CO LTD

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
HUNAN ZHENCHUANG ENVIRONMENTAL PROTECTION TECH CO LTD
Filing Date
2022-09-09
Publication Date
2026-06-09

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    Figure CN115539702B_ABST
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Abstract

A passive double liquid level controller based on floating ball control, a control switch is arranged at the upper end of the valve, the passive double liquid level controller comprises a passive double liquid level moving device, a lifting frame, a steel ball and a lever, the passive double liquid level moving device is connected to the lower end of the lifting frame, the lifting frame is arranged behind the lever, the steel ball is located in the lifting frame or the rear end of the lever, and the front end of the lever is pressed on the control switch of the valve. In the application, the control switch of the valve is automatically controlled by the rise and fall of the liquid level in the vacuum well, which can save labor and labor cost; when the floating ball moves along the floating rod between the first stop and the second stop, the state of the control switch of the valve can be maintained for a long time; and the double liquid level control of super long distance can be realized by changing the length of the floating rod between the first stop and the second stop.
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Description

Technical Field

[0001] This invention relates to a device for automatically controlling a valve, and more specifically, to a dedicated automatic control valve device that utilizes changes in liquid level (high or low) to achieve two-position control of valve opening and closing. Background Technology

[0002] Automatic water level control valves are frequently used in many devices. Due to their simple structure and low cost, purely mechanical float control valves are particularly widely used. In wastewater treatment, a sewage discharge valve is needed to control the liquid level in the wastewater tank during the extraction process. However, existing sewage discharge valves generally use sensors and electronic switches to control the sewage extraction and discharge process. Due to humid environments and harsh operating conditions, electronic control of the valve often leads to moisture damage and leakage of the electronic switches, causing them to malfunction. Therefore, it is essential to design a sewage discharge valve with good sealing properties that can operate in humid and complex environments without requiring electrical or chemical energy input. This invention aims to design a passive Schmidt vacuum sewage discharge valve with the above advantages, mainly used for urban drainage projects, domestic sewage, and vacuum collection and discharge of seepage water from underground buildings. It features high reliability, energy saving, and low construction costs.

[0003] In existing technology, there is a known float valve that includes a float and a valve body. A pressure valve is housed within the valve body, and a pressure rod is mounted on the pressure valve. The pressure rod is supported on the float wall. When the water level drops, the float descends, the force on the pressure rod decreases, and the pressure valve opens to allow water to flow in. When the water level rises, the float gradually rises, the force on the pressure rod gradually increases, pushing the pressure valve to close. Because this design lacks other switches or limit devices, it cannot achieve dual-position water level control, limiting its application. Furthermore, its high sensitivity leads to frequent opening and closing during use, resulting in a limited service life. Patent CN 1483975A discloses a two-position control float valve, including a float and a valve body. The left side of the float is connected to the right end of a float arm, and the left end of the float arm is provided with a fork. The float arm is rotatably connected to a connecting rod. A moving valve core is fixed to a spindle, and the right end of the spindle has a bend that inserts into the fork. The valve body contains a moving valve core and a fixed valve core, and the moving and fixed valve cores have matching water holes. The valve is opened and closed by using a fork with a certain spacing to drive the bend of the spindle and rotate it. This solves the problem of two-position control. However, there are still shortcomings: First, because the upper and lower liquid level differences within the control range are the same as the spacing of the fork, the stroke of the bend within the fork is limited, making it only suitable for replenishment two-position control with small liquid level differences. Summary of the Invention

[0004] The technical problem to be solved by this invention is that the structure of the sewage discharge device before the stop is relatively complex, and it needs to be controlled by the input of energy such as electricity. When used in complex environments such as humid conditions, its reliability is not high, and its energy consumption and construction costs are high, making it difficult to achieve long-stroke dual liquid level control of the valve. The invention proposes a device that achieves ultra-long-stroke dual liquid level control of the valve solely by the buoyancy of water on the float.

[0005] In response to the above problems, the technical solution proposed by the present invention is: a passive dual-level controller based on float control, wherein a control switch is provided at the upper end of the valve, the passive dual-level controller includes a passive dual-level moving device, a lifting frame, a steel ball and a lever, the passive dual-level moving device is connected to the lower end of the lifting frame, the lifting frame is located behind the lever, the steel ball is located in the lifting frame or at the rear end of the lever, and the front end of the lever is pressed against the control switch of the valve.

[0006] Preferably, the lever has an upper side at its rear end and a lower side at its lower end, with a partition strip between the upper and lower sides; when the steel ball is located at the rear end of the lever, the steel ball presses against the lower side.

[0007] Preferably, the rear end of the lever is A-shaped or H-shaped, and the upper side of the lever has a through positioning hole.

[0008] Preferably, it also includes a support mechanism, which includes a base plate, support plates and a crossbar. Two support plates are fixed parallel to each other on the base plate, and the crossbar passes through the two support plates so that both support plates are fixedly connected to the crossbar.

[0009] Preferably, each support plate is provided with an inwardly protruding stop, and the front end of one support plate is also provided with a folding plate, on which a transverse spring is connected, and the other end of the transverse spring is hooked on the upper side of the lever.

[0010] Preferably, it also includes a vertical spring, with hooks at both ends. The upper hook of the vertical spring hooks onto the support plate, and the lower hook of the vertical spring hooks onto the lifting frame.

[0011] Preferably, a guide plate is provided on the inner side of the rear end of each support plate. The length direction of the guide plate is vertical. Positioning grooves are opened on both sides of the lifting frame, and the guide plate is engaged in the positioning grooves.

[0012] Preferably, the lifting frame is also hinged with a flap, the rear end of which is in the lifting frame. When the steel ball is in the lifting frame, the steel ball is located at the rear end of the flap.

[0013] Preferably, the front end of the flap extends out of the lifting frame, and during the upward movement of the lifting frame, the front end of the flap can abut against the bottom of the baffle protrusion on the inner side of the support plate.

[0014] Preferably, the passive dual-level moving device includes a float, a float rod, a first stop, and a second stop. The first stop and the second stop are both mounted on the float rod. The float is fitted onto the float rod and is located between the first stop and the second stop. The upper end of the float rod is connected to the lower end of the lifting frame.

[0015] The beneficial technical effects of this invention are:

[0016] 1. In this invention, the valve control switch is automatically controlled by the rise and fall of the liquid level in the vacuum well, without the need for personnel intervention. It can automatically control the valve control switch in a timely and effective manner, saving manual labor and labor costs.

[0017] 2. In this invention, the valve's state does not require electrical components to sense it, and the opening and closing of the valve does not require electrical components to control it. That is, the opening and closing of the valve does not require any external power; it is entirely generated by the buoyancy of the water in the vacuum well on the float.

[0018] 3. In this invention, the control switch state of the valve is triggered by the movement of a float along the float rod, where it abuts against the first or second stop at either end of the float rod. However, when the float moves between the first and second stops, it does not change the control switch state of the valve, thus maintaining the control switch state of the valve for a long period.

[0019] 4. The present invention has a simple structure, low cost, and small size, and occupies little space when placed in a vacuum well.

[0020] 5. This invention is made of waterproof materials such as stainless steel or plastic, has a stable structure, is not easily deformed, can be used in humid environments, and has a long service life.

[0021] 6. Because the float of this invention rises and falls with the water level, and moves up and down along the float rod between the first and second stops, the state of the valve's control switch remains unchanged. Therefore, ultra-long-distance dual-level control can be achieved by changing the length of the float rod between the first and second stops. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of Example 1;

[0023] Figure 2 This is a three-dimensional structural diagram of Example 1 after removing the passive dual-level moving device;

[0024] Figure 3 This is a three-dimensional structural diagram of Example 1 excluding the passive dual-level moving device and the right-side support plate;

[0025] Figure 4 This is a schematic diagram of the lifting frame, lever, and valve in Example 1;

[0026] Figure 5 This is an enlarged view of the three-dimensional structure of the support plate;

[0027] Figure 6 A 3D structural diagram of the lifting frame, steel balls, and flap.

[0028] Figure 7 This is an enlarged view of the 3D structure of the lifting frame;

[0029] Figure 8 This is an enlarged cross-sectional view of the float.

[0030] In the diagram: Base plate 01, Bottom hole 02, Support plate 1, Support lug 11, Protrusion 12, Folding plate 13, Strip hole 14, Mounting plate 15, Guide plate 16, Lifting frame 2, Bottom frame plate 21, Top frame plate 22, Back plate 23, Positioning groove 24, Horizontal plate 25, Lifting lug 26, Hook 27, Side frame plate 28, Float 3, Outer side wall 31, Inner side wall 32, Cavity 33, Sliding hole 34, Float rod 4, First stop 41, Second stop 42, Lifting ring 43, Steel ball 5, Flip plate 6, Lever 7, Positioning hole 71, Spacer 72, Upper side 73, Lower side 74, Valve 8, Control switch 81, Front hinge rod 91, Rear hinge rod 92, Vertical spring 93, Horizontal spring 94, Crossbar 95. Detailed Implementation

[0031] The present invention will be further described below with reference to embodiments and accompanying drawings:

[0032] Example 1

[0033] like Figure 1 , Figure 2 and Figure 5 As shown, this embodiment includes a passive dual-level moving device, a support mechanism, a lifting frame 2, a steel ball 5, and a lever 7. The support mechanism includes a base plate 01, support plates 1, and a crossbar 95. Two support plates 1 are arranged parallel to each other on the base plate 01, and the lower end of each support plate 1 is bent outward to form a mounting plate 15, which is then fixed to the base plate 01. The rear end of each support plate 1 is bent inward to form a guide plate 16, with the length direction of the guide plate 16 being perpendicular to the vertical direction. A crossbar 95 passes through the two support plates 1, fixing both support plates 1 to the crossbar 95.

[0034] Each support plate 1 is provided with an inwardly protruding stop 12, and the rear end of the stop 12 of each support plate 1 has a vertically oriented strip hole 14. The front end of one support plate 1 is also provided with a folding plate 13, on which a transverse spring 94 is connected. Both ends of the transverse spring 94 are provided with hooks, and the other end of the transverse spring 94 hooks onto the upper side 73 of the lever 7. The upper end of each support plate 1 is provided with an outwardly bent support lug 11, and both ends of the vertical spring 93 are provided with hooks. The upper hook of the vertical spring 93 hooks onto the support lug 11 of the support plate 1, and the lower hook of the vertical spring 93 hooks onto the lifting frame 2.

[0035] like Figure 2 , Figure 3 , Figure 4 , Figure 6 and Figure 7 As shown, the upper end of the lifting frame 2 is provided with a top frame plate 22, the lower end of the lifting frame 2 is provided with a bottom frame plate 21, and the rear end of the lifting frame 2 is provided with a back plate 23. The upper end of the back plate 23 is seamlessly connected to the top frame plate 22, and the lower end of the back plate 23 is seamlessly connected to the bottom frame plate 21. Side frame plates 28 are provided on both sides of the front end of the lifting frame 2. The upper end of the side frame plate 28 is connected to the top frame plate 22, and the lower end of the side frame plate 28 is connected to the bottom frame plate 21. The top frame plate 22 and the bottom frame plate 21 both have inwardly recessed positioning grooves 24. The guide plate 16 at the rear end of the support plate 1 engages in the positioning grooves 24 of the top frame plate 22 and the bottom frame plate 21, allowing the lifting frame 2 to move along the guide plate 16. The crossbar 95 stabilizes the support plate 1, and the crossbar 95 at the upper and lower ends of the support plate 1 located at the position of the lifting frame 2 also acts as a stop, preventing the lifting frame 2 from detaching from the guide plate 16 when moving upward or downward.

[0036] A flap 6 is provided in the lifting frame 2, with its rear end inside the lifting frame 2 and its front end extending out of the lifting frame 2. Through mounting holes are provided on the side frame plates 28 on both sides of the lifting frame 2, and both ends of the rear hinge rod 92 pass through these mounting holes. The bottom of the flap 6 is fixedly connected to the rear hinge rod 92, so that the flap 6 is hinged inside the lifting frame 2. When the steel ball 5 is located in the lifting frame 2, the steel ball 5 presses against the flap 6, and the steel ball 5 is located at the rear end of the flap 6. A C-shaped opening is provided at the front end of the flap 6, and when the steel ball 5 is at the rear end of the lever 7, the lower end of the steel ball 5 abuts against the front end of the flap 6.

[0037] The bottom frame plate 21 of the lifting frame 2 bends downward and is seamlessly connected to the horizontal plate 25. The horizontal width of the horizontal plate 25 is greater than that of the bottom frame plate 21. Grooves are formed on the lower sides of both sides of the horizontal plate 25, forming lifting lugs 26. The lifting lugs 26 on both sides of the horizontal plate 25 pass through the strip holes 14 on the two support plates 1 respectively. The hook at the upper end of the vertical spring 93 hooks onto the support lug 11 of the support plate 1, and the hook at the lower end of the vertical spring 93 hooks onto the lifting lugs 26 of the bottom frame plate 21 of the lifting frame 2. A hook 27 is connected to the lower middle of the horizontal plate 25, and a lifting ring 43 is provided at the upper end of the float 4. The lifting ring 43 is embedded in the hook 27, so that the float 4 can drive the lifting frame 2 to move.

[0038] The front hinge rod 91 passes through the two support plates 1 and the lever 7, hinged between the two support plates 1. The front of the front hinge rod 91 is the front end of the lever 7, and the rear end of the lever 7 is the rear end of the lever 7. The front end of the lever 7 is positioned directly above the control switch 81 of the valve 8. When the lever 7 rotates clockwise, the front end of the lever 7 releases the control switch 81 of the valve 8, thereby opening the valve 8; when the lever 7 rotates counterclockwise, the front end of the lever 7 presses against the control switch 81 of the valve 8, thereby closing the valve 8.

[0039] The rear end of lever 7 is A-shaped, with the upper side 73 and the lower side 74. An arc-shaped partition 72 is provided between the upper side 73 and the lower side 74. When the steel ball 5 is located at the rear end of lever 7, it presses against the lower side 74, and its front end abuts against the partition 72. At this time, the two sides of the front end of the flap 6 abut against the two sides of the lower end of the steel ball 5. The rear end of lever 7 can be A-shaped, H-shaped, Y-shaped, etc., but is preferably A-shaped.

[0040] The lever 7 has two or more positioning holes 71 on its upper side 73, which are evenly distributed along the length of the upper side 73. One end of the hook of the transverse spring 94 is hooked onto the folding plate 13, and the other end of the hook of the transverse spring 94 is hooked into the positioning hole 71 on the upper side 73 of the lever 7. This ensures that the torque generated by the elastic force of the transverse spring 94 can balance the weight of the steel ball 5 and the rear end of the lever 7, as well as the torque generated by the supporting force of the control switch 81 of the valve 8.

[0041] like Figure 1 , Figure 3 , Figure 4 and Figure 8As shown, the passive dual-level moving device includes a float 3, a float rod 4, a first stop 41, and a second stop 42. The first stop 41 is installed at the upper end of the float rod 4, and the second stop 42 is installed at the lower end of the float rod 4. The float 3 is fitted onto the float rod 4 and is located between the first stop 41 and the second stop 42. A through bottom hole 02 is opened on the bottom plate 01, and the upper end of the float rod 4 passes through the bottom hole 02. A lifting ring 43 is provided at the upper end of the float rod 4, and the lifting ring 43 is engaged in the hook 27 at the lower end of the lifting frame 2, so that the float rod 4 can drive the lifting frame 2 to move.

[0042] The float 3 includes an outer side wall 31 and an inner side wall 32. The inner side wall 32 forms a hollow circular tube, and the hollow portion is a sliding hole 34. The float 3 is fitted onto the float rod 4 through the sliding hole 34. The float rod 4 is a smooth rod, allowing the float 3 to move freely along the float rod 4. The outer side wall 31 is located outside the inner side wall 32, and the outer side wall 31 and the inner side wall 32 are seamlessly connected. The outer side wall 31 and the inner side wall 32 form a closed, annular cavity 33.

[0043] The first stop 41 and the second stop 42 have the same structure, both including a main body and a screw. The main body has a through mounting hole through which the float 4 passes, allowing the main body to fit onto the float 4. The main body also has a threaded hole that communicates with the mounting hole. The screw is installed in the threaded hole via a threaded engagement, with the tip of the screw abutting against the float 4. Tightening the screw secures the first stop 41 and the second stop 42 firmly to the float 4.

[0044] like Figures 1 to 8 As shown, the specific principle of this embodiment is as follows: the entire device is fixedly installed in a vacuum well, and the lifting frame 2, steel ball 5, lever 7, and other components in the device are enclosed by a shield, leaving only the passive dual-level moving device exposed outside the shield. In other words, the water in the vacuum well will not come into contact with the components inside the shield, but can only come into contact with the passive dual-level moving device outside the shield.

[0045] When the water level is low, the steel ball 5 automatically falls into the lifting frame 2; therefore, the steel ball 5 is in the lifting frame 2 when the water level is low. When the water level in the vacuum well rises, the float 3 moves upward along the float rod 4 under the buoyancy of the water. As the water level gradually rises, the float 3 abuts against the first stop 41 on the float rod 4. The lifting frame 2 is also subjected to an upward pulling force from the vertical spring 93. At this time, the sum of the buoyancy force on the float 3 and the pulling force of the vertical spring 93 is greater than the weight of the steel ball 5, the lifting frame 2, and the passive dual-level moving device. This allows the float 3 to drive the float rod 4 upward through the first stop 41, and the float rod 4, in turn, drives the lifting frame 2 upward along the guide plate 16 through the hook 27. The flap 6 and the steel ball 5 in the lifting frame 2 move upward together with the lifting frame 2.

[0046] As the lifting frame 2 and the flip plate 6 move upward together, the front end of the flip plate 6 abuts against the stop protrusion 12 on the inner side of the support plate 1 during its upward movement, thus obstructing the front end of the flip plate 6. Meanwhile, the rear end of the flip plate 6 continues to rise; therefore, the flip plate 6, hinged within the lifting frame 2, will rotate counterclockwise. (From...) Figure 3 or Figure 4 (From the perspective of the angle) the height of the rear end of the flap 6 is greater than the height of the front end of the flap 6, and the steel ball 5 rolls forward along the flap 6 to the rear end of the A-shaped lever 7 under the action of gravity.

[0047] Under the influence of gravity on steel ball 5, the rear end of lever 7 rotates downwards, i.e., lever 7 rotates clockwise. At this time, the front end of lever 7 rotates upwards, causing the front end of lever 7 to release the control switch 81 of valve 8, thus opening the control switch 81 of valve 8. Simultaneously, the transverse spring 94 is stretched, and the torque generated by the elastic force of the transverse spring 94 balances the torque generated by the gravity of steel ball 5 and the rear end of lever 7. After the control switch 81 of valve 8 is opened, the vacuum well begins to drain water, causing the water level in the vacuum well to continuously decrease.

[0048] As the water level drops, float 3 moves downward along float rod 4. During this period, before float 3 abuts against the second stop 42, the lifting frame 2 remains above the guide plate 16 due to the tension of the vertical spring 93. The horizontal spring 94 hooks into a positioning hole 71 on the upper side 73 of lever 7, causing the rear end of lever 7 to tilt only slightly downward. At this time, the bottom of steel ball 5 presses against the lower side 74 of lever 7, and steel ball 5 tends to roll backward, but its rear end abuts against the front end of flap 6, so steel ball 5 remains at the rear end of lever 7 and will not fall. At this time, the elasticity of vertical spring 93 is used to balance the weight of lifting frame 2 and passive dual-level moving device, as well as the downward pressure of steel ball 5 on flap 6. During this process, the control switch 81 of valve 8 remains open.

[0049] As the water level continues to drop, the float 3 comes into contact with the second stop 42. Under the influence of gravity, the float 3 drives the float rod 4 and the lifting frame 2 downwards in sequence, stretching the vertical spring 93. As the lifting frame 2 moves downwards, the supporting force of the front end of the flap 6 on the steel ball 5 gradually decreases. Until the height of the rear hinge rod 92 of the hinged flap 6 is less than the height of the rear end of the lower side 74 of the lever 7, the steel ball 5, under the influence of gravity, rolls down along the lower side 74 of the lever 7 and the flap 6 into the lifting frame 2.

[0050] After the steel ball 5 enters the lifting frame 2, the weight of the steel ball 5 pressing on the lever 7 disappears. Under the elastic force of the transverse spring 94, the lever 7 rotates counterclockwise, causing the front end of the lever 7 to press against the control switch 81 of the valve 8 under the elastic force of the transverse spring 94, thereby closing the valve 8. After the valve 8 is closed, the vacuum well stops draining water.

[0051] After the steel ball 5 enters the lifting frame 2, under the action of the weight of the steel ball 5, the rear end of the flap 6 sinks down and abuts against the bottom frame plate 21, while the front end of the flap 6 tilts upward. Since the height of the end of the flap 6 near the back plate 23 of the lifting frame 2 is less than the height of the rear hinge rod 92 of the flap 6, the steel ball 5 can be relatively stably positioned inside the lifting frame 2.

[0052] When external water flows into the vacuum well, causing the water level to gradually rise, and during the period before the float 3 abuts against the first stop 41, the float 3 does not exert an upward force on the float rod 4. Therefore, the lifting frame 2 remains at the lower end of the guide plate 16 and does not rise with the float 3. During this period, the torque generated by the elastic force of the transverse spring 94 balances the weight of the rear end of the lever 7 and the torque generated by the upward supporting force of the control switch 81 of the valve 8, ensuring that the front end of the lever 7 remains pressed against the control switch 81 of the valve 8, thus maintaining the valve 8 in its original closed state.

[0053] In this embodiment, when the lifting frame 2 is at the lower end or the upper end of the guide plate 16, the vertical spring 93 applies an upward pulling force to the lifting frame 2; similarly, when the front end of the lever 7 is pressed against the control switch 81 of the valve 8 or when the front end of the lever 7 releases the control switch 81 of the valve 8, the horizontal spring 94 applies a pulling force to the lever 7 in the front direction.

[0054] Obviously, any improvements or modifications made without departing from the principles described in this invention should be considered within the scope of protection of this invention.

Claims

1. A passive dual-level controller based on float control, wherein a control switch is provided at the upper end of the valve, characterized in that, The passive dual-level controller includes a passive dual-level moving device, a lifting frame, a steel ball, and a lever. The passive dual-level moving device is connected to the lower end of the lifting frame, which is located behind the lever. The steel ball is located within the lifting frame or at the rear end of the lever. The front end of the lever presses against the control switch of the valve. The rear end of the lever has an upper side, and the lower end of the lever has a lower side. A spacer is provided between the upper and lower sides. When the steel ball is at the rear end of the lever, it presses against the lower side. The rear end of the lever is A-shaped or H-shaped, and the upper side of the lever has a through-hole positioning hole. It also includes... The system includes a support mechanism, which comprises a base plate, support plates, and a crossbar. Two support plates are fixed parallel to each other on the base plate, and the crossbar passes through the two support plates, thus fixing both support plates to the crossbar. Each support plate has an inwardly protruding stop, and a folding plate is also provided at the front end of one support plate. A transverse spring is connected to the folding plate, and the other end of the transverse spring is hooked into a positioning hole on the upper side of the lever. The system also includes a vertical spring, with hooks at both ends. The upper hook of the vertical spring hooks onto the support plate, and the lower hook hooks onto the lifting frame.

2. The passive dual-level controller based on float control according to claim 1, characterized in that, Each support plate has a guide plate on its inner rear end. The length of the guide plate is perpendicular to the vertical direction. The lifting frame has positioning grooves on both sides, and the guide plate is engaged in the positioning grooves.

3. A passive dual-level controller based on float control according to claim 2, characterized in that, The lifting frame is also hinged with a flap, the rear end of which is in the lifting frame. When the steel ball is in the lifting frame, it is located at the rear end of the flap.

4. A passive dual-level controller based on float control according to claim 3, characterized in that, The front end of the flap extends out of the lifting frame, and as the lifting frame moves upward, the front end of the flap can abut against the bottom of the inner side of the support plate.

5. A passive dual-level controller based on float control according to any one of claims 1 to 4, characterized in that, The passive dual-level moving device includes a float, a float rod, a first stop, and a second stop. The first stop and the second stop are both installed on the float rod. The float is fitted onto the float rod and is located between the first stop and the second stop. The upper end of the float rod is connected to the lower end of the lifting frame.