Flushing valve runner switching mechanism

The valve stem sliding is controlled by a combination of a reduction gear and a drive wheel, and the opening and closing of the flow channel is controlled by a Hall switch, which solves the installation space requirements and inertia damage problems of existing flush valves and achieves the miniaturization and cost reduction of flush valves.

CN223411605UActive Publication Date: 2025-10-03XIAMEN KENWOOD IND CO LTD
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Patent Information

Application Number
CN202422680337.3
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-11-04
Publication Date
2025-10-03
Estimated Expiration
2034-11-04

AI Technical Summary

Technical Problem

During production of existing flush valves, space must be reserved for installing a travel switch, which is not conducive to miniaturization and increases production costs. At the same time, when the motor drives the valve stem to move, it is easy to exceed the specified position and collide with the valve core to damage it.

Method used

The axial sliding of the valve stem is controlled by a combination of a reduction gear and a driving wheel. The movement range of the valve stem is limited by the stop ring area and the action ring area. The opening and closing of the flow channel is controlled by a Hall switch, eliminating the installation space for a travel switch.

Benefits of technology

The invention realizes the precise movement of the valve stem, avoids the damage caused by inertia, promotes the miniaturization production of the flush valve and reduces the production cost.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model provides a flushing valve flow channel switching mechanism which is installed at an opening of the side wall of a valve body in a connected mode, the valve body is provided with a flow channel, a valve element used for blocking the flow channel is installed at a valve opening of the valve body, a control motor used for controlling a reduction gear to rotate is installed in a shell, the control motor is started, the reduction gear rotates, and the flow channel is switched on. In the process that the mounting frame is firstly attached to the stop ring area from the point A to the point B, the end of the valve rod is separated from the valve element, the valve element blocks the valve port, and the flow channel is closed. The moving stroke of the valve rod is limited by the stop ring area A point, the stop ring area B point and the action ring area C point of the driving wheel and does not exceed the preset range, and the situation that in the prior art, after a motor is closed, the valve rod is still driven to move beyond the designated position under the inertia effect is avoided; and an installation space for installing the travel switch does not need to be reserved in the switching mechanism, so that the installation step of installing the part is omitted, the miniaturization production of the flushing valve is facilitated, and the production cost is reduced.
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Description

Technical Field

[0001] The invention relates to a flush valve flow channel switching mechanism. Background Art

[0002] Most flush valves available on the market use a motor to drive the valve stem to move to open the valve core to open and close the flow channel in the valve body. To determine whether the valve stem has moved to the correct position, a travel switch needs to be installed in the flush valve.

[0003] When producing the above-mentioned flush valve, considering the installation requirements of the travel switch, it is necessary to reserve installation space for the corresponding module components in the switching mechanism, which is not conducive to the miniaturization of the flush valve, and leads to an increase in the installation process and a corresponding increase in production costs; furthermore, when the motor drives the valve stem to move, when the valve stem moves to the specified position, the travel switch sends a closing command to the motor, and the motor's output shaft continues to drive the valve stem to slide forward one end distance under the action of inertia, causing the valve stem to move beyond the specified position and bump into and damage the valve core, thereby increasing the subsequent maintenance costs of the user when using the flush valve. Summary of the Invention

[0004] The present invention provides a flush valve flow channel switching mechanism, which can effectively solve the above problems.

[0005] The present invention is achieved in that:

[0006] A flush valve flow channel switching mechanism is installed at the opening of the valve body side wall. The valve body has a flow channel, and a valve core for blocking the flow channel is installed at the valve port of the valve body.

[0007] The switching mechanism includes a housing, a reduction gear and a valve stem. The reduction gear is rotatably mounted inside the housing. The valve stem is slidably fitted in the valve body opening, and the end of the valve stem is relative to the valve core. The valve stem is actuated by the reduction gear to be able to slide axially, and the axial movement direction of the valve stem is perpendicular to the axial direction of the reduction gear. A driving wheel that contacts and fits with the tail end of the mounting bracket is fixedly mounted on the end face of the reduction gear. The driving wheel includes a stop ring area and an action ring area that are connected along the rotation direction. The stop ring area is coaxially fixed with the reduction gear. The radius of the action ring area is larger than that of the stop ring area, and the centers of the two circles are staggered. The end where the stop ring area and the action ring area are connected is defined as point B, the opposite end is defined as point A, and the end of the action ring area away from point A is defined as point C.

[0008] A control motor for controlling the rotation of the reduction gear is installed in the housing. When the control motor is started and the reduction gear rotates, the mounting bracket first contacts the stop ring area from point A to point B. The end of the valve stem is separated from the valve core, the valve core blocks the valve port, and the flow channel is closed. Subsequently, when the mounting bracket contacts the action ring area from point B to point C, the valve stem is actuated by the action ring area with an increased radius, moves axially forward, pushes open the valve core, and the flow channel is opened.

[0009] As a further improvement, a magnet is embedded in the mounting bracket at the tail of the valve stem, and a Hall switch is installed on the inner wall surface of the shell close to the mounting bracket to cooperate with the magnetic induction of the magnet to control the opening and closing of water supply in the flow channel.

[0010] As a further improvement, the switching mechanism also includes a first gear rotatably arranged inside the housing, a second gear meshing with the first gear, a third gear coaxially fixed on the end face of the second gear, a fourth gear meshing with the third gear, and a fifth gear coaxially fixed on the end face of the fourth gear and meshing with the reduction gear; the module of each gear is 0.5, the number of teeth of the first gear is 12, the number of teeth of the second gear is 56, the number of teeth of the third gear is 12, the number of teeth of the fourth gear is 56, the number of teeth of the fifth gear is 12, and the number of teeth of the reduction gear is 60. The transmission ratio of the above four-stage transmission is 109.05:23.35:5:1.

[0011] As a further improvement, the output shaft of the control motor is fixedly connected to the first gear to drive the first gear to rotate; a push rod is slidably connected to the rear side wall inside the shell to push the magnet on the mounting frame to slide back and forth; an assembly plate is fixedly arranged on the rear side wall inside the shell, and a sliding hole for the push rod to be slidably connected is provided on the assembly plate; a button is screwed to the tail end of the push rod, and an extension hole for the button to slide with is provided on the rear side wall of the shell, and the end face of the button has a limiting ring that abuts against the edge of the extension hole to limit the button from being separated from the extension hole; a return spring is set on the peripheral side of the push rod between the button and the assembly plate.

[0012] As a further improvement, the outer shell is concave relative to the opening position of the valve body to form an installation thread groove, and a connecting piece is threaded in the installation thread groove, and the connecting piece has an integrally formed threaded portion, a convex portion and an embedded portion, and a through hole is provided from the threaded portion to the convex portion and the embedded portion for the valve stem to slide with; a screw cover is sleeved on the outer side of the convex portion, and the rear end of the screw cover extends inward to form a rest ring which is sleeved into the embedded groove of the rear end of the convex portion, and the inner wall surface of the screw cover has an internal thread, and a threaded ring column threaded on the inside of the screw cover is provided on the outside of the valve body interface. The valve stem is inserted into the opening of the valve body through the threaded ring column, and the screw cover is tightened to the outer side of the threaded ring column, so that the switching mechanism can be quickly assembled on the valve body.

[0013] As a further improvement, a reset spring is sleeved around the valve stem to provide the valve stem with a tendency to move backward; the threaded portion is threadedly engaged in the mounting threaded groove, an internal threaded hole is provided on the inner wall of the embedded portion, a locking sleeve is threaded in the internal threaded hole, and a accommodating groove for accommodating the reset spring is provided inside the locking sleeve. A contact ring is formed on the circumference of the valve stem near the mounting frame, and one force-bearing end of the reset spring contacts the bottom of the accommodating groove, and the other end contacts the contact ring.

[0014] As a further improvement, the front end of the embedded portion is provided with an insert ring which is tapered from front to back, and the outer side of the insert ring is sleeved with a sealing ring which is tightly fitted with the inner wall of the opening of the valve body.

[0015] As a further improvement, a PCB board is embedded in the top wall of the shell, the Hall switch is installed on the PCB board, the top wall of the shell has a detection area, and a touch sensing spring for controlling the start of the control motor is installed between the detection area of ​​the shell and the PCB board.

[0016] The beneficial effects of the present invention are:

[0017] The present application realizes the opening or closing of the valve core and then the opening or closing of the flow channel by actuating the axial sliding of the valve stem by the driving wheel. The movement stroke of the valve stem is limited by the stop ring area point A, point B and the action ring area point C of the driving wheel and will not exceed the preset range, thereby avoiding the situation in the prior art where the motor will still drive the valve stem to move beyond the specified position under the action of inertia after being turned off; and there is no need to reserve an installation space for installing a travel switch inside the switching mechanism, eliminating the installation steps of installing the component, which is conducive to the miniaturization production of flush valves and reduces production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 It is a cross-sectional schematic diagram of the internal structure of the switching mechanism of the present invention;

[0020] Figure 3 This is a structural diagram of the present invention that reflects the matching relationship between each gear and the reduction gear;

[0021] Figure 4 This is a schematic diagram of the state in which the flow channel is opened when the valve stem pushes the valve core open;

[0022] Figure 5 This invention Figure 4 The enlarged schematic diagram of point E in the middle;

[0023] Figure 6 This is a schematic diagram of the state in which the flow channel is closed when the valve stem and the valve core are separated;

[0024] Figure 7 This is a schematic diagram of the valve stem of the present invention when it is in an initial state after axially moving backward;

[0025] Figure 8 It is a schematic diagram of the state of the present invention when the axial forward movement is in the triggered state.

[0026] The accompanying drawings are marked as follows:

[0027] 10. Valve body; 11. Flow channel; 12. Stop spring; 101. Valve port; 102. Opening; 14. Threaded ring; 20. Switching mechanism; 21. Housing; 211. First gear; 212. Second gear; 213. Third gear; 214. Fourth gear; 215. Fifth gear; 22. Reduction gear; 23. Valve stem; 231. Mounting bracket; 232. Magnet; 233. Contact ring; 24. Hall switch; 25. Control motor; 210. Mounting thread groove; 26. Return spring; 27. Screw cap; 271. Shelf Ring; 28. Assembly plate; 281. Sliding hole; 29. ​​Extending hole; 30. Driving wheel; 31. Stop ring area; 32. Action ring area; 40. Valve core; 41. Gland portion; 42. Rod portion; 43. Sealing gasket; 50. Push rod; 51. Button; 511. Limiting ring; 52. Return spring; 60. Connecting piece; 601. Through hole; 61. Threaded portion; 62. Flange portion; 63. Embedded portion; 631. Insert ring; 64. Locking sleeve; 641. Accommodating groove; 70. Sealing ring; 80. Touch-sensitive spring; 90. PCB board. DETAILED DESCRIPTION

[0028] The present invention will be further described below with reference to the accompanying drawings and examples.

[0029] like Figures 1 to 8 As shown, the flush valve includes a valve body 10 and a switching mechanism 20 attached to an opening 102 on the side wall of the valve body 10. The valve body 10 has a flow channel 11. A valve core 40 for blocking the flow channel 11 is installed at the valve port 101 of the valve body 10. The switching mechanism 20 includes a housing 21, a reduction gear 22 and a valve stem 23. The reduction gear 22 is rotatably mounted inside the housing 21. The valve stem 23 is slidably fitted at the opening 102 of the valve body 10, and the end of the valve stem 23 is relative to the valve core 40. The valve stem 23 is actuated by the reduction gear 22 to slide axially, and the axial movement direction of the valve stem 23 is perpendicular to the axial direction of the reduction gear 22. A mounting bracket 231 provided at the tail of the valve stem 23 is embedded with a magnet 232. A Hall switch 24 is installed on the inner wall surface of the housing 21 near the mounting bracket 231 to cooperate with the magnet 232 to control the opening and closing of water supply in the flow channel 11.

[0030] like Figures 1 to 8As shown, the end face of the reduction gear 22 is fixed with a driving wheel 30 that contacts and cooperates with the tail end of the mounting bracket 231. The driving wheel 30 includes a stop ring area 31 and an action ring area 32 that are connected along the rotation direction. The stop ring area 31 is coaxially fixed with the reduction gear 22. The radius of the action ring area 32 is larger than the stop ring area 31 and the centers of the two circles are staggered. The end where the stop ring area 31 and the action ring area 32 connect is defined as point B, the opposite end is defined as point A, and the end of the action ring area 32 away from point A is defined as point C; a control motor 25 for controlling the rotation of the reduction gear 22 is installed in the housing 21. When the control motor 25 is started and the reduction gear 22 rotates, the mounting bracket 231 first contacts the stop ring area 31 from point A to point B. During this process, the end of the valve stem 23 is separated from the valve core 40, and the valve core 40 is sealed. The valve port 101 is blocked, the flow channel 11 is closed, and the Hall switch 24 is away from each other. At this time, the Hall switch 24 is not triggered, and the water supply in the flow channel 11 stops. Subsequently, when the mounting frame 231 contacts the action ring area 32 from point B to point C, the valve stem 23 is actuated by the action ring area 32 with an increased radius, moves axially forward, and pushes open the valve core 40, and the flow channel 11 opens. The N pole of the magnet 232 passes over the Hall switch 24 toward the direction close to the valve body 10, and the Hall switch 24 is triggered to output an induction signal to control the external water source component (not shown in the figure) to supply water to the flow channel 11. Of course, in other embodiments, it can also be set that when the S pole of the magnet 232 passes over the Hall switch 24, the Hall switch 24 is triggered to output an induction signal to control the external water source component to supply water to the flow channel 11. It should be noted here that the external water source component used in this application can be an angle valve or other water supply equipment.

[0031] The structures of the various components of the present invention are described below.

[0032] like Figures 2 to 6 As shown, it should be noted that the direction of rotation of the driving wheel 30 is clockwise. When the reduction gear 22 drives the driving wheel 30 to rotate, the mounting bracket 231 first contacts the stop ring area 31 of the driving wheel 30. During the contact process from point A to point B between the mounting bracket 231 and the stop ring area 31, the valve stem 23 is not subjected to force and does not undergo axial displacement. The valve body 10 is in an initial state where the flow channel 11 is closed and no water flow is supplied. This process takes 0.5s. As the driving wheel 30 continues to rotate clockwise, the mounting bracket 231 transitions to contact with the action ring area 32 of the driving wheel 30. During the contact process from point B to point C of 32, the action ring area 32 actuates the valve stem 23 to move axially forward, pushes open the valve core 40 and opens the flow channel 11. At this time, the Hall switch 24 is triggered to output a sensing signal and control the external water source to supply water to the flow channel 11. The valve body 10 is in a triggered state in which the flow channel 11 is open and water is supplied. This process takes 0.5s; if the driving wheel 30 continues to rotate clockwise at this time, the mounting bracket 231 quickly falls back from point C of the action ring area 32 to the initial state of contact with point A of the stop ring area 31, that is, at this time the flow channel 11 is quickly closed and there is no water supply in the valve body 10.

[0033] like Figure 4 and Figure 6 As shown, the valve core 40 includes an integrally formed pressure cover portion 41 for pressing and sealing the valve port 101 and a rod portion 42 extending downward from the middle of the lower end surface of the pressure cover portion 41. The water inlet end of the valve body 10 is provided with a flow-stop spring 12 that presses the pressure cover portion 41 downward to seal the valve core 40 and press the valve port 101. A sealing gasket 43 is interference-locked at the valve port 101; when the flow channel 11 is closed, the flow-stop spring 12 presses the pressure cover portion 41 downward and presses it at the valve port 101. At this time, the axis of the rod portion 42 is perpendicular to the axis of the valve stem 23. When the flow channel 11 is opened, the valve stem 23 slides forward and pushes the rod portion 50 42, causing its axis to deviate from the original axial position, driving one side of the pressure cover portion 41 to tilt up to open the valve port 101.

[0034] like Figure 3 As shown, the switching mechanism 20 further includes a first gear 211 rotatably disposed within the housing 21, a second gear 212 meshing with the first gear 211, a third gear 213 coaxially fixed to the end face of the second gear 212, a fourth gear 214 meshing with the third gear 213, and a fifth gear 215 coaxially fixed to the end face of the fourth gear 214 and meshing with the reduction gear 22. Each gear has a module of 0.5. The first gear 211 has 12 teeth, the second gear 212 has 56 teeth, the third gear 213 has 12 teeth, the fourth gear 214 has 56 teeth, the fifth gear 215 has 12 teeth, and the reduction gear 22 has 60 teeth. The transmission ratio of the above four-stage transmission is 109.05:23.35:5:1.

[0035] It is worth noting that after multiple tests, the above-mentioned multi-stage gear transmission method is used to drive the axial displacement of the valve stem 23. When testing the flushing diaphragm under 0.55 MPa, the valve stem 23 can push open the valve core 40 within 1 second, that is, it has the advantage of quickly opening the flow channel 11 and realizing water supply to the flow channel 11.

[0036] like Figure 2 and Figure 7 、 Figure 8As shown, the output shaft of the control motor 25 is fixedly connected to the first gear 211 to drive the first gear 211 to rotate; a push rod 50 is slidably connected to the rear side wall inside the housing 21 to push the magnet 232 on the mounting bracket 231 to slide back and forth; an assembly plate 28 is fixedly provided on the rear side wall inside the housing 21, and a sliding hole 281 for the push rod 50 to slide is provided on the assembly plate 28; a button 51 is screwed to the tail end of the push rod 50, and an extension hole 29 for the button 51 to slide with is provided on the rear side wall of the housing 21, and the end surface of the button 51 has A limiting ring 511 abuts against the edge of the extension hole 29 to limit the button 51 from being separated from the extension hole 29; a return spring 52 is provided between the button 51 and the assembly plate 28 and is connected to the circumference of the push rod 50; with this design, the user can choose to use the motor to control the rotation of the drive wheel 30 to actuate the axial sliding of the valve stem 23 according to the specific use environment, or to use the push rod 50 to synchronously actuate the magnet 232, the mounting bracket 231 and the valve stem 23 to slide axially. Compared with a single use method, the water control valve of the present application has a wider applicability.

[0037] like Figures 4 to 6 As shown, the housing 21 is concave relative to the opening 102 of the valve body 10 to form a mounting thread groove 210, and a connecting piece 60 is screwed into the mounting thread groove 210. The connecting piece 60 has an integrally formed screw portion 61, a convex portion 62 and an embedded portion 63. A through hole 601 for sliding cooperation of the valve stem 23 is opened from the screw portion 61 to the convex portion 62 and the embedded portion 63. A return spring 26 is sleeved on the circumference of the valve stem 23 to provide the valve stem 23 with a tendency to move backward; the screw portion 61 is screwed to the convex portion 62 and the embedded portion 63. The portion 61 is threadedly engaged in the mounting thread groove 210, and an internal threaded hole is provided on the inner wall of the embedded portion 63, in which a locking sleeve 64 is threaded, and an accommodating groove 641 for accommodating the reset spring 26 is provided inside the locking sleeve 64, and a contact ring 233 is formed on the circumference of the valve stem 23 near the mounting frame 231. One force-bearing end of the reset spring 26 contacts the bottom of the accommodating groove 641, and the other end contacts the contact ring 233, thereby providing the valve stem 23 with a tendency to move backward.

[0038] like Figures 4 to 6As shown, a screw cover 27 is sleeved on the outer side of the convex portion 62, and the rear end of the screw cover 27 extends inward to form a rest ring 271 that is sleeved into the embedded groove at the rear end of the convex portion 62. The inner wall surface of the screw cover 27 has an internal thread, and a threaded ring column 14 is provided on the outer side of the interface of the valve body 10, which is screwed to the inside of the screw cover 27. The valve stem 23 is inserted into the opening 102 of the valve body 10 through the threaded ring column 14. The screw cover 27 is tightened on the outer side of the threaded ring column 14, and the switching mechanism 20 can be quickly assembled on the valve body 10; at the front end of the embedded portion 63, there is a plug ring 631 that is tapered from front to back, and a sealing ring 70 is sleeved on the outer side of the plug ring 631, which is tightly fitted with the inner wall of the opening 102 of the valve body 10; through the provision of the sealing ring 70, water can be prevented from flowing into the switching mechanism 20 through the gap between the valve stem 23 and the opening 102, thereby improving the safety of the water control valve during use.

[0039] like Figure 7 and Figure 8 As shown, a PCB board 90 is embedded in the top wall of the housing 21, and the Hall switch 24 is installed on the PCB board 90. The top wall of the housing 21 has a detection area. A touch sensing spring 80 for controlling the start of the control motor 25 is installed between the detection area of ​​the housing 21 and the PCB board 90. When the user applies force to the corresponding position of the top wall of the housing 21, due to the thin thickness of the detection area of ​​the housing 21, the pressure applied by the hand indirectly acts on the touch sensing spring 80, and the PCB board 90 detects the electrical contact between the human hand and the touch sensing spring. The capacitance changes, which is converted into a corresponding electrical signal to control the start of the control motor 25. The valve stem 23 moves axially forward to push open the valve core 40, and the north pole of the magnet 232 approaches the Hall switch 24 to complete a valve opening action (i.e., the flow channel 11 is opened and water flow channel 11 is supplied). The valve stem 23 then moves axially backward to separate from the valve core 40, and the north pole of the magnet 232 moves away from the Hall switch 23 to complete a valve closing action. At this time, the control motor 25 is turned off. When the user removes the external force, the capacitance between the touch-sensitive spring 80 and the hand returns to its initial state. It should be noted here that a single touch can only control one flush valve to perform a single valve opening and closing action.

[0040] The above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. A person skilled in the art may make various modifications or changes without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also fall within the scope of the present invention and be defined by the claims.

Claims

1. A flush valve flow channel switching mechanism, wherein the switching mechanism (20) is attached to an opening (102) on a side wall of a valve body (10), the valve body (10) having a flow channel (11), and a valve core (40) for blocking the flow channel (11) is installed at a valve port (101) of the valve body (10), characterized in that: The switching mechanism (20) includes a housing (21), a reduction gear (22) and a valve stem (23). The reduction gear (22) is rotatably mounted inside the housing (21). The valve stem (23) is slidably fitted at the opening (102) of the valve body (10) and the end of the valve stem (23) is positioned relative to the valve core (40). The valve stem (23) is actuated by the reduction gear (22) to slide axially. The axial movement direction of the valve stem (23) is perpendicular to the axial direction of the reduction gear (22). The end face of the reduction gear (22) is fixedly mounted. A driving wheel (30) is provided which is in contact with the tail end of the mounting frame (231). The driving wheel (30) includes a stop ring area (31) and an action ring area (32) which are connected along the rotation direction. The stop ring area (31) is fixed coaxially with the reduction gear (22). The radius of the action ring area (32) is larger than that of the stop ring area (31), and the centers of the two circles are staggered. The end where the stop ring area (31) and the action ring area (32) are connected is defined as point B, the opposite end is defined as point A, and the end of the action ring area (32) away from point A is defined as point C. A control motor (25) for controlling the rotation of the reduction gear (22) is installed in the housing (21). When the control motor (25) is started and the reduction gear (22) rotates, the mounting frame (231) first contacts the stop ring area (31) from point A to point B, and the end of the valve stem (23) is separated from the valve core (40), the valve core (40) blocks the valve port (101), and the flow channel (11) is closed; then, when the mounting frame (231) contacts the action ring area (32) from point B to point C, the valve stem (23) is actuated by the action ring area (32) with an increased radius, moves axially forward, and pushes open the valve core (40), and the flow channel (11) is opened.

2. A flush valve flow channel switching mechanism according to claim 1, characterized in that: A magnet (232) is embedded in a mounting bracket (231) provided at the tail of the valve stem (23), and a Hall switch (24) is installed on the inner wall surface of the housing (21) near the mounting bracket (231) to cooperate with the magnetic induction of the magnet (232) to control the opening and closing of water supply in the flow channel (11).

3. The flush valve flow channel switching mechanism according to claim 1, characterized in that: The switching mechanism (20) further comprises a first gear (211) rotatably arranged inside the housing (21), a second gear (212) meshed with the first gear (211), a third gear (213) coaxially fixed on the end face of the second gear (212), a fourth gear (214) meshed with the third gear (213), and a fifth gear (215) coaxially fixed on the end face of the fourth gear (214) and meshed with the reduction gear (22); the module of each gear is 0.5, the number of teeth of the first gear (211) is 12, the number of teeth of the second gear (212) is 56, the number of teeth of the third gear (213) is 12, the number of teeth of the fourth gear (214) is 56, the number of teeth of the fifth gear (215) is 12, and the number of teeth of the reduction gear (22) is 60. The transmission ratio of the above four-stage transmission is 109.05:23.35:5:

1.

4. A flush valve flow channel switching mechanism according to claim 3, characterized in that: The output shaft of the control motor (25) is fixedly connected to the first gear (211) and is used to drive the first gear (211) to rotate; a push rod (50) is slidably connected to the rear side wall inside the shell (21) for pushing the magnet (232) on the mounting frame (231) to slide back and forth; an assembly plate (28) is fixedly arranged on the rear side wall inside the shell (21), and a sliding hole (281) for sliding connection of the push rod (50) is opened on the assembly plate (28); a button (51) is screwed to the tail end of the push rod (50), and an extension hole (29) for sliding engagement with the button (51) is opened on the rear side wall of the shell (21), and the end face of the button (51) has a limiting ring (511) that abuts against the edge of the extension hole (29) to limit the button (51) from being separated from the extension hole (29); a return spring (52) is arranged between the button (51) and the assembly plate (28) and is sleeved on the circumference of the push rod (50).

5. The flush valve flow channel switching mechanism according to claim 1, characterized in that: The housing (21) is concave relative to the opening (102) of the valve body (10) to form a mounting thread groove (210), and a connecting piece (60) is screwed into the mounting thread groove (210). The connecting piece (60) has an integrally formed screw connection portion (61), a convex portion (62) and an embedded portion (63). A through hole (601) for sliding engagement of the valve stem (23) is provided from the screw connection portion (61) to the convex portion (62) and the embedded portion (63); a screw cap (27) is sleeved on the outer side of the convex portion (62). The rear end of the rotary cover (27) extends inward to form a rest ring (271) that is inserted into the groove at the rear end of the convex edge (62). The inner wall surface of the rotary cover (27) has an internal thread. A threaded ring column (14) that is screwed to the inside of the rotary cover (27) is provided on the outside of the interface of the valve body (10). The valve stem (23) is inserted into the opening (102) of the valve body (10) through the threaded ring column (14). The rotary cover (27) is tightened to the outside of the threaded ring column (14), and the switching mechanism (20) can be quickly assembled on the valve body (10).

6. A flush valve flow channel switching mechanism according to claim 5, characterized in that: A return spring (26) is sleeved on the circumferential side of the valve stem (23) to provide the valve stem (23) with a tendency to move backward; the threaded portion (61) is threadedly engaged in the mounting thread groove (210), an internal threaded hole is provided on the inner wall of the embedded portion (63), a locking sleeve (64) is threaded in the internal threaded hole, and a receiving groove (641) for accommodating the return spring (26) is provided inside the locking sleeve (64), and a contact ring (233) is formed on the circumferential side of the valve stem (23) near the mounting frame (231), and one force-bearing end of the return spring (26) contacts the bottom of the receiving groove (641), and the other end contacts the contact ring (233).

7. The flush valve flow channel switching mechanism according to claim 5, characterized in that: A plug ring (631) is provided at the front end of the embedded portion (63) and is tapered from front to back. A sealing ring (70) is sleeved on the outer side of the plug ring (631) and is tightly fitted with the inner wall of the opening (102) of the valve body (10).

8. The flush valve flow channel switching mechanism according to claim 2, wherein: A PCB board (90) is embedded on the top wall of the housing (21), a Hall switch (24) is mounted on the PCB board (90), the top wall of the housing (21) has a detection area, and a touch sensing spring (80) for controlling the start of the control motor (25) is installed between the detection area of ​​the housing (21) and the PCB board (90).