A dry-wet separation sewage treatment device

By introducing a gradient-decreasing filter screen frame and a convenient activated carbon frame fixing mechanism into the wastewater treatment device, the problems of cumbersome activated carbon plate replacement and inaccurate clogging judgment are solved, achieving efficient wastewater treatment and equipment maintenance.

CN224377723UActive Publication Date: 2026-06-19TIANJIN REDSUN WATER IND

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
TIANJIN REDSUN WATER IND
Filing Date
2025-07-04
Publication Date
2026-06-19

AI Technical Summary

Technical Problem

Existing dry-wet separation wastewater treatment devices require tools to loosen and tighten bolts when replacing activated carbon plates, which is cumbersome and laborious. Furthermore, it is impossible to accurately determine the clogging status of the filter plates in a timely manner, leading to reduced filtration efficiency or equipment blockage.

Method used

A wastewater treatment device comprising a frame, a filter screen frame, and an activated carbon frame was designed. The filter screen frame has a gradually decreasing pore size gradient, and the activated carbon frame is located below. Vibration is reduced by shock-absorbing wheels, and the observation window facilitates observation. The ball rod and spring fixing mechanism simplifies operation, and the spring resets and locks in place, enabling convenient replacement and fixation.

Benefits of technology

It enables convenient replacement of activated carbon plates and real-time monitoring of filter plate status, improving filtration efficiency, reducing equipment vibration, and lowering operation difficulty and operating costs.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN224377723U_ABST
    Figure CN224377723U_ABST
Patent Text Reader

Abstract

This utility model belongs to the field of wastewater treatment technology, and in particular to a dry-wet separation wastewater treatment device, including a frame. A filtration mechanism is installed inside the frame, and the filtration mechanism includes a filter screen frame. The filter screen frame screens and traps wastewater through its aperture. A fixing mechanism is used to fix the filter screen frame. A spring and a ball rod are fixedly installed. After the ball rod is compressed and removed from the frame, the spring can reset it, locking it in a limiting groove, thereby fixing the activated carbon frame and the filter screen frame. The limiting groove is shaped like a triangular pyramid, providing precise guidance to ensure the correct reset and locking of the ball rod. The spring is made of silicon-chromium steel, which has excellent elasticity and fatigue resistance, maintaining stable mechanical properties during long-term use. This solves the technical problem that in wastewater treatment, each replacement of the activated carbon plate requires tools to unscrew and tighten bolts, resulting in numerous, time-consuming, and labor-intensive operations.
Need to check novelty before this filing date? Find Prior Art

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, and in particular to a dry-wet separation wastewater treatment device. Background Technology

[0002] Wastewater refers to water discharged from domestic and industrial processes that has been polluted to a certain extent and has lost its original function. Wastewater treatment is the process of purifying wastewater to meet the water quality requirements for discharge into a water body or for reuse. Wastewater treatment is widely used in various fields such as construction, agriculture, transportation, energy, petrochemicals, environmental protection, urban landscaping, medical care, and catering, and is increasingly becoming a part of the daily lives of ordinary people.

[0003] Chinese Patent CN214972034U discloses a dry-wet separation wastewater treatment device, including a main body, a filter plate, a bracket, and a support rod. The filter plate is located inside the main body, and a collar is connected to the filter plate internally via an inlaid method. The bracket is fixedly connected inside the main body, and a support rod is located at the top of the bracket, passing through the collar. This dry-wet separation wastewater treatment device solves the problem of inconvenient removal of internal solids in traditional dry-wet separation wastewater treatment devices by incorporating a specially structured filter plate inside the main body. When the filter plate becomes clogged with separated solids from the wastewater, simply remove the cover, use a tool to hook up the top filter plate, clean it, and then put it back in place. This achieves rapid cleaning of the separated solids. The overall structure is simple and very convenient to operate.

[0004] However, the above-mentioned solutions require tools to loosen and tighten bolts each time the activated carbon plate is replaced during sewage treatment. This involves many steps, is time-consuming and labor-intensive, and operators cannot directly observe the degree of clogging of the filter plates. They can only judge by the equipment's operating status, such as a slowdown in water flow, or by periodic disassembly and cleaning. This makes it impossible to grasp the actual working status of the filter plates in a timely and accurate manner, which leads to reduced filtration efficiency or equipment clogging. Therefore, a dry-wet separation sewage treatment device is proposed to solve the above-mentioned problems. Utility Model Content

[0005] To address the technical problem that replacing activated carbon plates during wastewater treatment requires using tools to loosen and tighten bolts, resulting in numerous, time-consuming, and labor-intensive steps, and that operators can only judge the actual working status of the filter plates by the equipment's operating status or periodic disassembly and cleaning, making it impossible to timely and accurately grasp the actual working status of the filter plates, this application provides a dry-wet separation wastewater treatment device.

[0006] The present invention proposes a dry-wet separation sewage treatment device, which includes a frame and a filtration mechanism inside the frame. The filtration mechanism includes a filter screen frame, which screens and retains sewage through its aperture.

[0007] The frame is equipped with a fixing mechanism, which includes a ball rod. The movement of the ball rod fixes the filter frame.

[0008] Preferably, the filtration mechanism further includes shock-absorbing wheels, which are fixedly installed on the lower surface of the frame, and an observation window is fixedly bonded to the rear surface of the frame with a waterproof adhesive.

[0009] The above technical solution involves fixing the shock-absorbing wheels to the frame. The shock-absorbing wheels are model CFP01-D125-UR from Yiheda. This model of shock-absorbing wheel has a good shock-absorbing structure, which can effectively absorb the vibration generated during equipment operation, protect the internal components of the frame, and extend the service life. The frame is fixedly bonded to the observation window with waterproof adhesive, which not only fixes it but also facilitates replacement. The observation window can be made of special soda-lime glass, which has high mechanical strength after tempering and can avoid damage due to external forces.

[0010] Preferably, a plurality of the filter frames are slidably inserted into the inner wall of the groove of the frame, and the aperture of the plurality of filter frames is distributed in a gradient decreasing from top to bottom, and the filter frames are made of stainless steel.

[0011] The above technical solution uses a sliding connection between the filter screen frame and the frame, which not only fixes the filter screen frame but also makes it easy to remove. The front end of the filter screen frame is equipped with a handle, which allows the operator to remove the filter screen frame. The filter screen frame has a gradient decreasing distribution of aperture from top to bottom, forming a multi-stage filtration system that can gradually remove suspended solids and particles of different sizes from the wastewater. The filter screen frame is made of stainless steel, which has good corrosion resistance and can resist the erosion of chemicals and microorganisms in the wastewater, ensuring the long-term stable operation of the filter screen frame.

[0012] Preferably, an activated carbon frame is slidably inserted into the inner wall of the groove of the frame, the activated carbon frame is located below the filter screen frame, and the outer surfaces of the activated carbon frame and the outer surfaces of the filter screen frame are both fixedly bonded with a sealing layer by a waterproof adhesive, the sealing layer being made of nitrile rubber.

[0013] The above technical solution utilizes a frame that slides into the activated carbon holder, allowing for both fixation and easy disassembly. The activated carbon on the holder is secured with a waterproof adhesive for easy replacement. A handle allows operators to remove the holder and replace or regenerate the activated carbon, using methods such as heat or chemical regeneration, to extend its lifespan and reduce operating costs. Positioned below the filter screen, the activated carbon holder allows wastewater to undergo initial filtration before being adsorbed by the activated carbon, further purifying the water. Both the activated carbon holder and the filter screen are sealed with a waterproof adhesive, ensuring both fixation and easy replacement. The sealing layer, made of nitrile rubber, prevents leakage during filtration, offering excellent resistance to most oils and chemicals and good elasticity, effectively preventing wastewater leakage.

[0014] Preferably, a water inlet pipe is fixedly connected to the upper surface of the frame, a dust cover is slidably inserted into the groove at the top of the water inlet pipe, a water outlet pipe with a valve is fixedly connected to the bottom side of the frame, and a handle is fixedly installed on the left side surface of the frame.

[0015] With the above technical solution, the frame is fixedly connected to the water inlet pipe, allowing workers to inject wastewater through the water inlet pipe. The water inlet pipe is slidably inserted into the dust cover, sealing the water inlet pipe without affecting the removal of the dust cover. The frame is fixedly connected to the water outlet pipe with a valve, facilitating the flow of filtered water through the water outlet pipe. The valve can regulate the water flow rate. The frame is fixedly installed with a handle, which makes it easy for workers to move the frame.

[0016] Preferably, the fixing mechanism further includes springs, which are respectively fixedly installed on the inner wall of the front groove of the filter screen frame and the inner wall of the front groove of the activated carbon frame, and the springs are made of silicon chromium steel.

[0017] The above technical solution uses springs to fix the filter screen frame and activated carbon frame in their grooves. The springs are made of silicon chromium steel, which has excellent elasticity and fatigue resistance, and can maintain stable mechanical properties during long-term use.

[0018] Preferably, the ball rod is slidably inserted into the inner wall of the front groove of the filter screen frame and the inner wall of the front groove of the activated carbon frame, respectively. The spring is fixedly installed on the lower surface of the ball rod. A limiting groove is formed on the inner wall of the front of the frame, and the inner wall of the limiting groove is slidably connected to the arc surface of the ball rod.

[0019] The above technical solution involves slidingly inserting the ball rod into the filter frame and activated carbon frame respectively, fixing them without affecting their lifting and lowering. The ball rod is fixedly installed with a spring, and after the ball rod is squeezed down, the spring can reset it and lock it in the limiting groove, thereby fixing the activated carbon frame and filter frame. The limiting groove is slidably connected to the ball rod, and the limiting groove is triangular pyramid in shape, which can provide precise guidance and ensure the correct reset and locking of the ball rod.

[0020] The beneficial effects of this utility model are as follows:

[0021] 1. By setting up a filtration mechanism, wastewater is screened and intercepted. The shock-absorbing wheels can absorb the vibration generated during equipment operation. The observation window can be made of special soda-lime glass, which has high mechanical strength. The pore size of the filter screen frame decreases from top to bottom, forming a multi-stage filtration system that can gradually remove suspended solids and particles of different sizes from the wastewater. The activated carbon frame is located below the filter screen frame to further purify the water. The sealing layer can prevent wastewater leakage during the filtration process. The operator can inject wastewater through the inlet pipe. The dust cover seals the inlet pipe without affecting the removal of the dust cover. The filtered water flows out through the outlet pipe. The valve can regulate the water flow. The handle makes it easy for the operator to move the frame. This solves the technical problem that when treating wastewater, the operator cannot directly observe the degree of clogging of the filter plate. They can only judge by the equipment's operating status, such as a slowdown in water flow, or by periodic disassembly and cleaning. This makes it impossible to grasp the actual working status of the filter plate in a timely and accurate manner, which leads to reduced filtration efficiency or equipment clogging.

[0022] 2. By setting up a fixing mechanism, the filter screen frame is fixed. The spring and the ball rod are fixedly installed. After the ball rod is squeezed and removed from the frame, the spring can reset it and lock it in the limiting groove, thereby fixing the activated carbon frame and the filter screen frame. The limiting groove is shaped like a triangular pyramid, which can provide precise guidance and ensure the correct reset and locking of the ball rod. The spring is made of silicon chromium steel, which has excellent elasticity and fatigue resistance, and can maintain stable mechanical properties during long-term use. This solves the technical problem that when replacing activated carbon plates in sewage treatment, it is necessary to use tools to unscrew and tighten bolts every time, which is a lot of operation steps and time-consuming and labor-intensive. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a dry-wet separation wastewater treatment device proposed in this utility model;

[0024] Figure 2 This is a perspective view of the inlet pipe structure of a dry-wet separation sewage treatment device proposed in this utility model;

[0025] Figure 3This is a perspective view of the ball-and-bar structure of a dry-wet separation wastewater treatment device proposed in this utility model;

[0026] Figure 4 This is a perspective view of the limiting tank structure of a dry-wet separation sewage treatment device proposed in this utility model;

[0027] Figure 5 This is a perspective view of the filter screen frame structure of a dry-wet separation wastewater treatment device proposed in this utility model;

[0028] Figure 6 This is a perspective view of the activated carbon frame structure of a dry-wet separation wastewater treatment device proposed in this utility model;

[0029] Figure 7 This is a perspective view of the sealing layer structure of a dry-wet separation wastewater treatment device proposed in this utility model.

[0030] In the diagram: 1. Frame; 2. Shock-absorbing wheels; 21. Observation window; 3. Filter rack; 4. Activated carbon rack; 41. Sealing layer; 5. Water inlet pipe; 51. Dust cover; 52. Water outlet pipe; 53. Handle; 6. Spring; 7. Cue stick; 71. Limiting groove. Detailed Implementation

[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0032] Reference Figures 1-7 A dry-wet separation wastewater treatment device includes a frame 1, and a filtration mechanism is provided inside the frame 1. The filtration mechanism includes a filter screen frame 3, which screens and retains wastewater through its aperture.

[0033] The filtration mechanism also includes a shock-absorbing wheel 2, which is fixedly installed on the lower surface of the frame 1. An observation window 21 is fixedly bonded to the rear surface of the frame 1 with a waterproof adhesive. The shock-absorbing wheel 2 is fixedly installed to the frame 1 with the shock-absorbing wheel 2. The shock-absorbing wheel 2 is model CFP01-D125-UR from Yiheda. This model of shock-absorbing wheel 2 has a good shock-absorbing structure, which can effectively absorb the vibration generated during the operation of the equipment, protect the internal components of the frame 1, and extend the service life. The frame 1 is fixedly bonded to the observation window 21 with a waterproof adhesive, which not only fixes it but also facilitates replacement. The material of the observation window 21 can be special soda-lime glass, which has been tempered and has high mechanical strength, so as to avoid damage due to external forces.

[0034] Multiple filter frames 3 are slidably inserted into the inner wall of the groove of the frame 1. The aperture of the multiple filter frames 3 decreases in a gradient from top to bottom. The filter frames 3 are made of stainless steel. The filter frames 3 are slidably inserted into the frame 1, which not only fixes them but also makes them easy to remove. The front end of the filter frame 3 is provided with a handle, which can be used by the operator to remove the filter frame 3. The gradient distribution of aperture of the filter frames 3 from top to bottom forms a multi-stage filtration system, which can gradually remove suspended solids and particles of different sizes from the sewage. The stainless steel material of the filter frames 3 has good corrosion resistance and can resist the erosion of chemicals and microorganisms in the sewage, ensuring the long-term stable operation of the filter frames 3.

[0035] An activated carbon rack 4 is slidably inserted into the inner wall of the groove of frame 1. The activated carbon rack 4 is located below the filter rack 3. A sealing layer 41, made of nitrile rubber, is fixedly bonded to the outer surfaces of both the activated carbon rack 4 and the filter rack 3 using a waterproof adhesive. The frame 1 and activated carbon rack 4 are slidably inserted into each other, securing the rack while facilitating disassembly. The activated carbon on the activated carbon rack 4 is fixedly bonded to it with a waterproof adhesive for easy replacement. A handle is provided on the rack, allowing workers to remove it and replace or regenerate the activated carbon inside, such as through heating regeneration. Alternatively, chemical regeneration can be used to extend the service life of activated carbon and reduce operating costs. With the activated carbon frame 4 located below the filter screen frame 3, wastewater can undergo preliminary filtration through the filter screen frame 3 and then be further purified by adsorption through the activated carbon frame 4. Both the activated carbon frame 4 and the filter screen frame 3 are bonded with a sealing layer 41 using a waterproof adhesive, which not only fixes them but also facilitates replacement. The sealing layer 41 prevents wastewater leakage during the filtration process. The material of the sealing layer 41 is nitrile rubber, which has good resistance to most oils and chemicals and good elasticity, effectively preventing wastewater leakage.

[0036] A water inlet pipe 5 is fixedly connected to the upper surface of the frame 1. A dust cover 51 is slidably inserted into the groove at the top of the water inlet pipe 5. A water outlet pipe 52 with a valve is fixedly connected to the bottom side of the frame 1. A handle 53 is fixedly installed on the left side surface of the frame 1. The frame 1 is fixedly connected to the water inlet pipe 5 and fixed thereto. Workers can inject sewage through the water inlet pipe 5. The water inlet pipe 5 is slidably inserted into the dust cover 51, which seals the water inlet pipe 5 without affecting the removal of the dust cover 51. The frame 1 is fixedly connected to the water outlet pipe 52 with a valve, which facilitates the flow of filtered water through the water outlet pipe 52. The valve can regulate the flow rate of water. The handle 53 is fixedly installed on the frame 1 and fixed thereto. The handle 53 is designed to facilitate the movement of the frame 1 by workers.

[0037] By setting up a filtration mechanism, wastewater is screened and intercepted. The shock-absorbing wheel 2 can absorb the vibration generated during equipment operation. The observation window 21 can be made of special soda-lime glass, which has high mechanical strength. The pore size of the filter screen frame 3 is distributed in a gradient decreasing distribution from top to bottom, forming a multi-stage filtration system that can gradually remove suspended solids and particles of different sizes from the wastewater. The activated carbon frame 4 is located below the filter screen frame 3 to further purify the water quality. The sealing layer 41 can prevent wastewater leakage during the filtration process. The operator can inject wastewater through the inlet pipe 5. The dust cover 51 seals the inlet pipe 5 without affecting the removal of the dust cover 51. The filtered water flows out through the outlet pipe 52. The valve can regulate the flow rate of the water. The handle 53 makes it easy for the operator to move the frame 1. This solves the technical problem that when treating wastewater, the operator cannot directly observe the degree of clogging of the filter plate. They can only judge by the equipment's operating status, such as the water flow speed slowing down, or by periodically disassembling and cleaning. They cannot grasp the actual working status of the filter plate in a timely and accurate manner, which leads to reduced filtration efficiency or equipment clogging.

[0038] The frame 1 is equipped with a fixing mechanism, which includes a ball rod 7. The movement of the ball rod 7 fixes the filter frame 3.

[0039] The fixing mechanism also includes spring 6, which is fixedly installed on the inner wall of the front groove of the filter screen frame 3 and the inner wall of the front groove of the activated carbon frame 4. The spring 6 is made of silicon chromium steel. It is fixedly installed in the grooves of the filter screen frame 3 and the activated carbon frame 4 to fix them. The spring 6 is made of silicon chromium steel, which has excellent elasticity and fatigue resistance, and can maintain stable mechanical properties during long-term use.

[0040] The ball rod 7 is slidably inserted into the inner wall of the front groove of the filter frame 3 and the inner wall of the front groove of the activated carbon frame 4, respectively. The spring 6 is fixedly installed on the lower surface of the ball rod 7. A limiting groove 71 is opened on the inner wall of the front end of the frame 1. The inner wall of the limiting groove 71 is slidably connected to the arc surface of the ball rod 7. The ball rod 7 is slidably inserted into the filter frame 3 and the activated carbon frame 4, respectively, which fixes them without affecting their lifting and lowering. The ball rod 7 is fixedly installed by the spring 6. After the ball rod 7 is squeezed down, the spring 6 can reset it and lock it in the limiting groove 71, thereby fixing the activated carbon frame 4 and the filter frame 3. The ball rod 7 is slidably connected by the limiting groove 71, and the limiting groove 71 is in the shape of a triangular pyramid, which can provide precise guidance to ensure the correct reset and locking of the ball rod 7.

[0041] The filter screen frame 3 is fixed by a fixing mechanism. The spring 6 and the ball rod 7 are fixedly installed. After the ball rod 7 is squeezed and removed from the frame, the spring 6 can reset it and lock it in the limiting groove 71, thereby fixing the activated carbon frame 4 and the filter screen frame 3. The limiting groove 71 is shaped like a triangular pyramid, which can provide precise guidance to ensure the correct reset and locking of the ball rod 7. The spring 6 is made of silicon chromium steel, which has excellent elasticity and fatigue resistance, and can maintain stable mechanical properties during long-term use. This solves the technical problem that when replacing activated carbon plates in sewage treatment, tools are needed to unscrew and tighten bolts every time, which is time-consuming and labor-intensive.

[0042] Working principle: When sewage needs to be treated, the staff removes the dust cover 51 on the inlet pipe 5 and injects sewage into the frame 1 through the inlet pipe 5. The sewage first passes through the filter screen 3. The pore size of the filter screen 3 decreases from top to bottom, gradually removing suspended solids and particles of different sizes from the sewage. The sewage that has been initially filtered flows into the activated carbon frame 4 below. The activated carbon on the activated carbon frame 4 adsorbs the sewage and further purifies the water quality. The treated water flows out through the outlet pipe 52 on the side of the bottom end of the frame 1. A valve is installed on the outlet pipe 52 to regulate the flow rate of the water.

[0043] When staff observe through observation window 21 that a filter holder 3 is clogged or an activated carbon holder 4 needs replacement, they remove the filter holder 3 or activated carbon holder 4 using the handle. During removal, the ball rod 7, which is slidably inserted into the filter holder 3 or activated carbon holder 4, is compressed by frame 1 and retracts into the groove on the filter holder 3 or activated carbon holder 4, thereby releasing the filter holder 3 or activated carbon holder 4 from its fixation. After cleaning or replacing the filter holder 3 or activated carbon holder 4, it is reinserted into frame 1. During insertion, the filter... The ball rod 7, which is slidably inserted into the frame 3 or activated carbon frame 4, is also squeezed by the frame 1 and retracts into the groove. When it moves to the lower limit groove 71 on the frame 1, the spring 6 resets the ball rod 7 and locks it in the limit groove 71, thereby fixing the filter frame 3 or activated carbon frame 4. The sealing layer 41 on the filter frame 3 and activated carbon frame 4 can prevent sewage leakage. The shock-absorbing wheel 2 under the frame 1 can absorb the vibration generated during the operation of the equipment and protect the internal components of the frame 1. The handle 53 set on the frame 1 makes it easy for the staff to move the frame 1.

[0044] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A dry-wet separation sewage treatment device comprising a frame (1), characterized in that: The frame (1) is equipped with a filtration mechanism, which includes a filter screen frame (3) that filters and retains wastewater through its aperture. The frame (1) is provided with a fixing mechanism, which includes a ball rod (7). The movement of the ball rod (7) fixes the filter frame (3).

2. The dry-wet separation sewage treatment device according to claim 1, characterized in that: The filtration mechanism also includes a shock-absorbing wheel (2), which is fixedly installed on the lower surface of the frame (1). An observation window (21) is fixedly bonded to the rear end surface of the frame (1) by a waterproof adhesive.

3. The dry-wet separation sewage treatment device according to claim 1, characterized in that: Multiple filter frames (3) are slidably inserted into the inner wall of the groove of the frame (1). The aperture of the multiple filter frames (3) is distributed in a gradient decreasing from top to bottom. The filter frames (3) are made of stainless steel.

4. The dry-wet separation sewage treatment device according to claim 3, characterized in that: An activated carbon frame (4) is slidably inserted into the inner wall of the groove of the frame (1). The activated carbon frame (4) is located below the filter screen frame (3). The outer surface of the activated carbon frame (4) and the outer surface of the filter screen frame (3) are both fixedly bonded with a sealing layer (41) by a waterproof adhesive. The material of the sealing layer (41) is nitrile rubber.

5. The device according to claim 1, wherein: The upper surface of the frame (1) is fixedly connected to a water inlet pipe (5), and a dust cover (51) is slidably inserted into the groove at the top of the water inlet pipe (5). The bottom side of the frame (1) is fixedly connected to a water outlet pipe (52) with a valve, and a handle (53) is fixedly installed on the left side surface of the frame (1).

6. The device according to claim 4, wherein: The fixing mechanism also includes a spring (6), which is fixedly installed on the inner wall of the front groove of the filter frame (3) and the inner wall of the front groove of the activated carbon frame (4). The spring (6) is made of silicon chromium steel.

7. A dry-wet separation sewage treatment device according to claim 6, characterized in that: The ball rod (7) is slidably inserted into the inner wall of the front groove of the filter frame (3) and the inner wall of the front groove of the activated carbon frame (4). The spring (6) is fixedly installed on the lower surface of the ball rod (7). A limiting groove (71) is opened on the inner wall of the front end of the frame (1). The inner wall of the limiting groove (71) is slidably connected to the arc surface of the ball rod (7).