Discharging mechanism of screw cold header

By combining a belt conveyor and an air jet assembly, the discharge mechanism of the screw cold heading machine is automatically cleaned, solving the problem of impurity accumulation on the conveyor surface and improving equipment efficiency and finished product quality.

CN224128537UActive Publication Date: 2026-04-17YIGAO AUTO PARTS (SUZHOU) CO LTD
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
YIGAO AUTO PARTS (SUZHOU) CO LTD
Filing Date
2025-04-29
Publication Date
2026-04-17

AI Technical Summary

Technical Problem

The discharge mechanism of the existing cold heading screw machine is prone to accumulating impurities during high-speed transmission, which leads to a decrease in the friction coefficient, transmission failure and mechanical wear, and requires frequent shutdowns for cleaning, affecting equipment efficiency and finished product quality.

Method used

The system employs a belt conveyor combined with an air jet assembly and a cleaning assembly. A motor-driven gear ring rotates the brushes for cleaning, compressed air removes residue, and a water washing assembly cleans the brushes, achieving automated cleaning.

Benefits of technology

It effectively removes residue and dirt from the surface of the conveyor, avoids transmission failures, improves the efficiency of continuous operation of the equipment, reduces the frequency of manual cleaning, and ensures the quality of finished screws.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model discloses a discharging mechanism of a screw cold header, which relates to the technical field of discharging mechanisms and comprises a mounting frame and an air injection component. A belt conveyor is mounted in the mounting frame, a supporting frame is fixed to the rear side of the mounting frame, a stirring assembly and a cleaning assembly are mounted on the front side of the supporting frame, and a gas injection assembly is mounted on the front side of the cleaning assembly; a rotating assembly is installed on the side face of the supporting frame, the shifting assembly is connected with the rotating assembly, the input end of the belt conveyor is electrically connected with the output end of an external control switch set, and two opposite supports are fixed to the left end and the right end of the lower side of the mounting frame. And the air injection assembly comprises a connecting frame, a first motor, a rotating shaft, an L-shaped connecting plate, a rotating barrel, an air outlet pipe, a one-way valve and a supporting seat, the connecting frame is fixed to the rear side of the supporting frame, and residues and dirt attached to the surface can be removed during use.
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Description

Technical Field

[0001] This utility model relates to the field of material discharge mechanism technology, specifically to a material discharge mechanism for a screw cold heading machine. Background Technology

[0002] In the cold heading process of screws, the unloading mechanism is a core component connecting the forming process and subsequent processing, primarily responsible for the orderly receiving and directional conveying of the cold-headed screws. Existing technologies mostly employ chute-type or conveyor belt-type unloading devices, utilizing gravity or mechanical power to achieve continuous screw transport through inclined metal chutes or circulating conveyor belts. Some equipment incorporates a vibrating screen or sorting mechanism at the end of the chute for initial screw arrangement and orientation. These mechanisms are typically made of stainless steel or hardened metal, with polished surfaces to reduce the coefficient of friction, and are equipped with protective covers to prevent foreign object intrusion.

[0003] However, existing discharge mechanisms have significant drawbacks during operation: First, during high-speed transport, metal shavings, cold heading oil residue, and processing dust falling from the screw surface easily form a mixed contaminant layer on the conveying surface. Traditional structures lack self-cleaning designs, leading to continuous accumulation of impurities and the formation of caking. Second, these deposits not only reduce the friction coefficient of the conveying surface, causing screw slippage and accumulation, but also accelerate mechanical wear due to metal shavings embedded in equipment gaps. Third, contaminants require manual cleaning by stopping the machine, necessitating a production line interruption for scraping every 2-3 hours on average, severely impacting the continuous operation efficiency of the equipment. Furthermore, the adhesive residue formed by the mixture of oil and metal powder may contaminate the surface of the finished screws, increasing energy consumption and wastewater treatment pressure in subsequent cleaning processes. Therefore, we propose a discharge mechanism for a screw cold heading machine. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the existing defects and provide a discharge mechanism for a screw cold heading machine that can remove residues and dirt adhering to the surface during use, which can effectively solve the problems in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a discharge mechanism for a screw cold heading machine, comprising a mounting frame and an air jet assembly;

[0006] Mounting frame: An internal belt conveyor is installed. A support frame is fixed to the rear side of the mounting frame. An actuating component and a cleaning component are installed to the front side of the support frame. An air injection component is installed to the front side of the cleaning component. A rotating component is installed on the side of the support frame. The actuating component is connected to the rotating component. The input end of the belt conveyor is electrically connected to the output end of an external control switch group. Two opposing brackets are fixed to the left and right ends of the lower side of the mounting frame.

[0007] The jet assembly includes a connecting frame, a first motor, a rotating shaft, an L-shaped connecting plate, a rotating drum, an air outlet pipe, a one-way valve, and a support base. The connecting frame is fixed to the rear of the support frame, and the first motor is mounted on the rear of the connecting frame. A rotating shaft is fixed to the output shaft of the first motor. Two corresponding L-shaped connecting plates are fixed to the circumference of the rotating shaft, and a rotating drum is positioned between the two L-shaped connecting plates. Two corresponding rotating holes are opened on the front side of the L-shaped connecting plates. The front and rear ends of the two rotating drums are rotatably connected to the interiors of the four rotating holes. Evenly distributed air outlet holes are opened on the circumference of the rotating drum, and an air outlet pipe is fixed inside each air outlet hole. A one-way valve is mounted on the circumference of the air outlet pipe. A support base is located at the front end of the rotating shaft, and a mounting hole is opened on the upper side of the support base. The front end of the rotating shaft is rotatably connected to the interior of the mounting hole. A cleaning component is mounted on the circumference of the rotating drum. The air injection component is connected to the two rotating drums. The input end of the first motor is electrically connected to the output end of an external control switch group. Compressed air is sprayed onto the belt conveyor by the jet assembly.

[0008] Furthermore, the cleaning assembly includes a fixing ring, a connecting strip, and bristles. Two corresponding fixing rings are fixed on the circumference of the rotating drum, and a connecting strip is fixed between the two fixing rings. A connecting strip is fixed on the side of the connecting strip, and bristles are fixed in a uniform manner. The belt conveyor is cleaned by setting up the cleaning assembly.

[0009] Furthermore, the actuating assembly includes a rotating ring, an external gear ring, an internal gear ring, and a gear ring. The support frame has an opening in the middle, and the rotating ring is rotatably connected inside the opening. An external gear ring is fixed on the circumferential surface of the rotating ring, and an internal gear ring is fixed inside the rotating ring. A gear ring is fixed at the rear end of the circumferential surface of the rotating drum. Both gear rings mesh with the internal gear ring. The actuating assembly drives the two rotating drums to rotate.

[0010] Furthermore, the rotating assembly includes a second motor and a gear. The second motor is mounted on the rear side of the support frame, and a gear is fixed on the output shaft of the second motor. The gear meshes with the external gear ring. The input end of the second motor is electrically connected to the output end of an external control switch group. The rotating assembly drives the external gear ring to rotate.

[0011] Furthermore, the cleaning assembly includes a water tank, an inlet pipe, a nozzle, a mounting bucket, a guide pipe, and a connecting flange ring. The water tank is fixed to the front side of the support frame and is fixed to the lower side of the mounting frame. The water tank has evenly distributed water inlets on both the left and right sides. An inlet pipe is fixed inside the water inlet. A nozzle is installed on the end face of the inlet pipe inside the water tank. Two corresponding mounting buckets are fixed to the ends of all the inlet pipes away from the nozzles. All the inlet pipes communicate with the inner cavities of the two mounting buckets respectively. An opening is opened on the circumferential surface of the mounting bucket. A guide pipe is fixed inside the opening. A connecting flange ring is fixed to the right end of the circumferential surface of the guide pipe. The cleaning assembly is used to clean the bristles that have been used for a long time.

[0012] Furthermore, the air injection assembly includes a connecting ring, a first connecting hose, a second connecting hose, a connecting pipe, and an air pump. The front end of the inside of the rotating drum is rotatably connected to the connecting ring. The first connecting hose and the second connecting hose are respectively fixed inside the two connecting rings. The lower ends of the first connecting hose and the second connecting hose are connected to the connecting pipe. An air pump is installed on the front side of the water tank. The air outlet of the air pump is fixed inside the right end of the connecting pipe. Compressed air is injected into the inside of the two rotating drums by setting the air injection assembly.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: The discharge mechanism of this screw cold heading machine has the following advantages:

[0014] 1. By setting up a belt conveyor to discharge the screws cold-forged by the screw cold-forging machine, the second motor is started during the discharge process to make the gears rotate. The rotation of the gears drives the outer gear ring to rotate, which in turn drives the inner gear ring to rotate. The rotation of the inner gear ring causes the two gear rings to rotate. The rotation of the two gear rings drives all the connecting strips and the evenly distributed bristles fixed on their sides to rotate, thus cleaning the surface of the belt conveyor. In this way, the residue and dirt on the surface of the belt conveyor can be removed, so as to prevent these residues and dirt from affecting the discharge of the belt conveyor.

[0015] 2. By setting up an air injection component, the air pump can be started during use to inject compressed air into the interior of the two rotating drums through the first connecting hose and the second connecting hose. The compressed air that enters the interior of the two rotating drums will be sprayed onto the belt conveyor through evenly distributed air outlet pipes. In this way, the residue and dirt on the surface of the belt conveyor can be further removed.

[0016] 3. By setting up a first motor, after prolonged use, the first motor can be started to rotate the shaft, causing the two L-shaped connecting plates to rotate. The rotation of the two L-shaped connecting plates causes the two rotating barrels to move, so that the upper rotating barrel moves to the left side and corresponds to all the nozzles on the left. Then, the two rotating barrels are controlled to rotate. During the rotation of the two rotating barrels, external water is injected into the interior of all the water inlet pipes on the left through the guide pipe on the left. Then, all the nozzles on the left spray onto the evenly distributed bristles on the outside of the corresponding rotating barrel. In this way, the bristles can be cleaned after prolonged use, which is convenient for subsequent use. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the front structure of this utility model;

[0018] Figure 2 This is a schematic diagram of the jet assembly structure of this utility model;

[0019] Figure 3 This is a schematic diagram of the cleaning component structure of this utility model;

[0020] Figure 4 This is a schematic diagram of the cleaning component structure of this utility model;

[0021] Figure 5 This is a schematic diagram of the rear structure of this utility model.

[0022] In the diagram: 1. Mounting frame, 2. Belt conveyor, 3. Support frame, 4. Jet assembly, 41. Connecting frame, 42. First motor, 43. Rotary shaft, 44. L-shaped connecting plate, 45. Rotary drum, 46. Air outlet pipe, 47. One-way valve, 48. Support base, 5. Actuating assembly, 51. Rotating ring, 52. External gear ring, 53. Internal gear ring, 54. Gear ring, 6. Rotating assembly, 61. Second motor, 62. Gear, 7. Cleaning assembly, 71. Fixing ring, 72. Connecting strip, 73. Brush bristles, 8. Cleaning assembly, 81. Water tank, 82. Water inlet pipe, 83. Nozzle, 84. Mounting drum, 85. Guide pipe, 86. Connecting flange ring, 9. Air injection assembly, 91. Connecting ring, 92. First connecting hose, 93. Second connecting hose, 94. Connecting pipe, 95. Air pump, 10. Bracket. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] Please see Figure 1-5This embodiment provides a technical solution: a discharge mechanism for a screw cold heading machine, including a mounting frame 1 and an air jet assembly 4;

[0025] Mounting frame 1: A belt conveyor 2 is installed inside. A support frame 3 is fixed to the rear side of mounting frame 1. An actuating component 5 and a cleaning component 8 are installed on the front side of support frame 3. An air injection component 9 is installed on the front side of cleaning component 8. A rotating component 6 is installed on the side of support frame 3. The actuating component 5 is connected to the rotating component 6. The input end of the belt conveyor 2 is electrically connected to the output end of an external control switch group. Two opposing brackets 10 are fixed at the left and right ends of the lower side of mounting frame 1. The actuating component 5 includes a rotating ring 51, an external gear ring 52, an internal gear ring 53, and a gear ring 54. An opening is provided in the middle of support frame 3. The rotating ring 51 is rotatably connected inside the opening. The circumferential surface of the rotating ring 51... An external gear ring 52 is fixed on the top, and an internal gear ring 53 is fixed inside the rotating ring 51. A gear ring 54 is fixed at the rear end of the circumference of the rotating drum 45. Both gear rings 54 mesh with the internal gear ring 53. The rotating assembly 6 includes a second motor 61 and a gear 62. The second motor 61 is mounted on the rear side of the support frame 3. A gear 62 is fixed on the output shaft of the second motor 61. The gear 62 meshes with the external gear ring 52. The input end of the second motor 61 is electrically connected to the output end of an external control switch group. The cleaning assembly 8 includes a water tank 81, a water inlet pipe 82, a nozzle 83, a mounting bucket 84, a guide pipe 85, and a connecting flange ring 86. The water tank 81 is fixed on the front side of the support frame 3. 81 is fixed to the lower side of the mounting bracket 1. Water inlets are evenly distributed on both the left and right sides of the water tank 81. Water inlet pipes 82 are fixed inside the water inlets. Spray nozzles 83 are installed on the end face of the water inlet pipes 82 inside the water tank 81. Two corresponding mounting buckets 84 are fixed to the ends of all water inlet pipes 82 away from the spray nozzles 83. All water inlet pipes 82 communicate with the inner cavities of the two mounting buckets 84 respectively. An opening is opened on the circumferential surface of the mounting bucket 84. A guide pipe 85 is fixed inside the opening. A connecting flange ring 86 is fixed to the right end of the circumferential surface of the guide pipe 85. The air injection assembly 9 includes a connecting ring 91, a first connecting hose 92, a second connecting hose 93, and a connecting pipe 94. 4. An air pump 95 is rotatably connected to the front end of the rotating drum 45. The first connecting hose 92 and the second connecting hose 93 are fixed inside the two connecting rings 91 respectively. The lower ends of the first connecting hose 92 and the second connecting hose 93 are connected to the connecting pipe 94. An air pump 95 is installed on the front side of the water tank 81. The air outlet of the air pump 95 is fixed to the right end of the connecting pipe 94. Compressed air is injected into the interior of the two rotating drums 45 by setting the air injection component 9. The bristles 73 that have been used for a long time are cleaned by setting the cleaning component 8. The outer toothed ring 52 is rotated by setting the rotating component 6. The two rotating drums 45 are rotated by setting the actuating component 5.

[0026] The jet assembly 4 includes a connecting frame 41, a first motor 42, a rotating shaft 43, an L-shaped connecting plate 44, a rotating drum 45, an air outlet pipe 46, a one-way valve 47, and a support base 48. The connecting frame 41 is fixed to the rear side of the support frame 3, and the first motor 42 is mounted on the rear side of the connecting frame 41. A rotating shaft 43 is fixed to the output shaft of the first motor 42. Two corresponding L-shaped connecting plates 44 are fixed to the circumferential surface of the rotating shaft 43. A rotating drum 45 is positioned between the two L-shaped connecting plates 44. Two corresponding rotating holes are opened on the front side of the L-shaped connecting plates 44. The front and rear ends of the two rotating drums 45 are rotatably connected to the interiors of the four rotating holes. Evenly distributed air outlet holes are opened on the circumferential surface of the rotating drum 45. An air outlet pipe 46 is fixed inside each air outlet hole, and an air outlet pipe 46 is mounted on the circumferential surface of the air outlet pipe 46. There is a one-way valve 47, and a support base 48 is provided at the front end of the rotating shaft 43. The upper side of the support base 48 has a mounting hole. The front end of the rotating shaft 43 is rotatably connected to the inside of the mounting hole. A cleaning component 7 is installed on the circumferential surface of the rotating drum 45. An air injection component 9 is connected to the two rotating drums 45. The input end of the first motor 42 is electrically connected to the output end of an external control switch group. The cleaning component 7 includes a fixing ring 71, a connecting strip 72, and bristles 73. Two corresponding fixing rings 71 are fixed on the circumferential surface of the rotating drum 45. A uniformly distributed connecting strip 72 is fixed between the two fixing rings 71. A uniformly distributed bristle 73 is fixed on the side of the connecting strip 72. The belt conveyor 2 is cleaned by setting the cleaning component 7, and compressed air is sprayed onto the belt conveyor 2 by setting the air jet component 4.

[0027] The working principle of the discharge mechanism of the screw cold heading machine provided by this utility model is as follows: First, the belt conveyor 2 is placed below the discharge port of the screw cold heading machine. Then, the belt conveyor 2 is controlled to discharge the screws cold-headed by the screw cold heading machine. During the discharge process, the second motor 61 is started to make the gear 62 rotate. The rotation of the gear 62 drives the outer gear ring 52 to rotate, which in turn drives the inner gear ring 53 to rotate. The rotation of the inner gear ring 53 causes the two gear rings 54 to rotate. The rotation of the two gear rings 54 drives the two rotating drums 45 to rotate. The rotation of the upper rotating drum 45 drives the two rotating drums 45 to rotate. The rotating of all the connecting strips 72 and the evenly distributed bristles 73 fixed on its side can clean the surface of the belt conveyor 2, thus removing residues and dirt from the surface of the belt conveyor 2 and preventing these residues and dirt from affecting the output of the belt conveyor 2. During the cleaning process, the air pump 95 can be started to inject compressed air into the interior of the two rotating drums 45 through the first connecting hose 92 and the second connecting hose 93. The compressed air entering the two rotating drums 45 will be sprayed out through the evenly distributed air outlet pipes 46. In this case, the belt conveyor 2 can further remove residue and dirt from its surface. After prolonged use, the first motor 42 can be started to rotate the shaft 43, which in turn rotates the two L-shaped connecting plates 44. The rotation of the two L-shaped connecting plates 44 causes the two rotating drums 45 to move, so that the upper rotating drum 45 moves to the left side and corresponds to all the nozzles 83 on the left. Then, the two rotating drums 45 are rotated, and external water is injected into the interior of all the water inlet pipes 82 on the left through the guide pipe 85 on the left. Then, all the nozzles 83 on the left spray onto the evenly distributed bristles 73 on the outside of the corresponding rotating drum 45. In this case, the bristles 73 that have been used for a long time can be cleaned. During the cleaning process, the rotating drum 45 on the right will drive the cleaning component 7 on the right to rotate upward. In this case, the bristles 73 of the cleaning component 7 will be in contact with the lower surface of the belt conveyor 2. After contact, the rotation of all the bristles 73 can be controlled to clean the belt conveyor 2. The cleaned bristles 73 will be dried on the left side for subsequent use.

[0028] It is worth noting that the external control switch group disclosed in the above embodiments is equipped with buttons that correspond one-to-one with the belt conveyor 2, the first motor 42, the second motor 61 and the air pump 95. The belt conveyor 2, the first motor 42, the second motor 61 and the air pump 95 can be freely configured according to the actual application scenario.

[0029] The above are merely embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A delivery mechanism for a screw cold header, characterized by: Includes mounting bracket (1) and jet assembly (4); Mounting frame (1): A belt conveyor (2) is installed inside. A support frame (3) is fixed to the rear side of the mounting frame (1). A toggle assembly (5) and a cleaning assembly (8) are installed on the front side of the support frame (3). An air injection assembly (9) is installed on the front side of the cleaning assembly (8). A rotating assembly (6) is installed on the side of the support frame (3). The toggle assembly (5) is connected to the rotating assembly (6). The input end of the belt conveyor (2) is electrically connected to the output end of an external control switch group. Two opposing brackets (10) are fixed at the left and right ends of the lower side of the mounting frame (1). The jet assembly (4) includes a connecting frame (41), a first motor (42), a rotating shaft (43), an L-shaped connecting plate (44), a rotating drum (45), an exhaust pipe (46), a one-way valve (47), and a support base (48). The connecting frame (41) is fixed to the rear side of the support frame (3). The first motor (42) is installed on the rear side of the connecting frame (41). The rotating shaft (43) is fixed on the output shaft of the first motor (42). Two corresponding L-shaped connecting plates (44) are fixed on the circumferential surface of the rotating shaft (43). A rotating drum (45) is provided between the two L-shaped connecting plates (44). Two corresponding rotating holes are opened on the front side of the L-shaped connecting plate (44). The two rotating drums (46) are connected to the rotating shaft (47). 5) The front and rear ends are respectively rotatably connected to the interior of the four rotating holes. The rotating barrel (45) has evenly distributed air outlets on its circumferential surface. An air outlet pipe (46) is fixed inside the air outlet. A one-way valve (47) is installed on the circumferential surface of the air outlet pipe (46). A support seat (48) is provided at the front end of the rotating shaft (43). An installation hole is provided on the upper side of the support seat (48). The front end of the rotating shaft (43) is rotatably connected to the interior of the installation hole. A cleaning component (7) is installed on the circumferential surface of the rotating barrel (45). The air injection component (9) is connected to the two rotating barrels (45). The input end of the first motor (42) is electrically connected to the output end of the external control switch group.

2. A delivery mechanism for a screw cold header as defined in claim 1, characterized in that: The cleaning assembly (7) includes a fixing ring (71), a connecting strip (72) and bristles (73). Two corresponding fixing rings (71) are fixed on the circumferential surface of the rotating drum (45). A connecting strip (72) is fixed between the two fixing rings (71). A bristle (73) is fixed on the side of the connecting strip (72). All the bristles (73) on the upper side are in contact with the lower side of the belt conveyor (2).

3. The delivery mechanism of a screw cold header as claimed in claim 1, characterized in that: The actuating assembly (5) includes a rotating ring (51), an external gear ring (52), an internal gear ring (53), and a gear ring (54). The support frame (3) has an opening in the middle, and the rotating ring (51) is rotatably connected inside the opening. An external gear ring (52) is fixed on the circumferential surface of the rotating ring (51), and an internal gear ring (53) is fixed inside the rotating ring (51). A gear ring (54) is fixed at the rear end of the circumferential surface of the rotating barrel (45), and both gear rings (54) mesh with the internal gear ring (53).

4. A delivery mechanism for a screw cold header as defined in claim 3, characterized in that: The rotating assembly (6) includes a second motor (61) and a gear (62). The second motor (61) is mounted on the rear side of the support frame (3). The gear (62) is fixed on the output shaft of the second motor (61). The gear (62) meshes with the external gear ring (52). The input end of the second motor (61) is electrically connected to the output end of an external control switch group.

5. The delivery mechanism of a screw cold header as claimed in claim 1, characterized in that: The cleaning assembly (8) includes a water tank (81), an inlet pipe (82), a nozzle (83), a mounting bucket (84), a guide pipe (85), and a connecting flange ring (86). The water tank (81) is fixed to the front side of the support frame (3). The water tank (81) is fixed to the lower side of the mounting frame (1). The water tank (81) has evenly distributed water inlets on both the left and right sides. The water inlets are fixed with inlet pipes (82). The nozzles (83) are installed on the end face of the inlet pipes (82) located inside the water tank (81). Two corresponding mounting buckets (84) are fixed at the ends of all the inlet pipes (82) away from the nozzles (83). All the inlet pipes (82) are connected to the inner cavities of the two mounting buckets (84). An opening is opened on the circumferential surface of the mounting bucket (84). The guide pipe (85) is fixed inside the opening. The connecting flange ring (86) is fixed at the right end of the circumferential surface of the guide pipe (85).

6. A delivery mechanism for a screw cold header as defined in claim 5, wherein: The air injection assembly (9) includes a connecting ring (91), a first connecting hose (92), a second connecting hose (93), a connecting pipe (94), and an air pump (95). The front end of the rotating drum (45) is rotatably connected to the connecting ring (91). The first connecting hose (92) and the second connecting hose (93) are respectively fixed inside the two connecting rings (91). The lower ends of the first connecting hose (92) and the second connecting hose (93) are connected to the connecting pipe (94). The air pump (95) is installed on the front side of the water tank (81). The right end of the connecting pipe (94) is fixed to the inside of the air outlet of the air pump (95).