Omni-directional two-dimensional fountain device without rotating electric ring and control method of omni-directional two-dimensional fountain device

Abstract

The invention discloses an omni-directional two-dimensional fountain device without a rotating electric ring and a control method of the omni-directional two-dimensional fountain device, and belongs to the technical field of fountain waterscape engineering. The device comprises a nozzle assembly, a rotating joint assembly, a coaxial nesting pipe assembly, a horizontal driving mechanism and a vertical driving mechanism, the coaxial nested pipe assembly comprises an outer pipe and an inner pipe coaxially and rotatably arranged in the outer pipe, and a water inlet hole is formed in the inner pipe to form a water supply channel; the rotary joint assembly comprises a fixed joint and a movable joint, the fixed joint is connected with the inner pipe, and the movable joint is rotatably connected to the fixed joint; the horizontal driving mechanism drives the inner pipe and the fixed joint to horizontally rotate; the vertical driving mechanism is provided with a vertical output shaft penetrating through the interior of the inner pipe, and the shaft drives the movable connector to rotate in the vertical plane through a transmission assembly. Through a coaxial nested transmission structure, continuous omnidirectional rotation of the spray head in horizontal and vertical planes is realized, the problems of abrasion and water resistance of a rotating electric ring are thoroughly solved, the structure is compact, and the operation is reliable.

Description

Technical Field

[0001] This invention relates to the field of fountain and water feature engineering technology, and in particular to an omnidirectional two-dimensional fountain device without rotating electric rings and its control method. Background Technology

[0002] With the development of urban landscape construction, fountain performances are becoming increasingly diverse, and the requirements for the freedom of nozzle movement are also increasing. Existing two-dimensional fountain devices (i.e., nozzles that can change the water spray angle in both horizontal and vertical directions) typically employ the following technical solutions:

[0003] Rotary slip ring solution: Power and control signals are transmitted to the motor of the rotating part through a rotating slip ring (conductive slip ring), enabling multi-degree-of-freedom movement of the nozzle. However, rotating slip rings suffer from problems such as rapid brush wear and limited lifespan; moreover, long-term immersion in water or in humid environments can easily lead to short circuits, resulting in high maintenance costs and safety hazards.

[0004] The non-electric ring superposition scheme involves directly superimposing two one-dimensional fountain mechanisms. Due to the limitation of cable entanglement, this scheme can usually only perform reciprocating motion within a certain range, and cannot achieve continuous omnidirectional rotation in the horizontal or vertical directions, thus limiting the expressiveness of the water shapes.

[0005] External motor linkage solution: The motor is mounted on a fixed base and drives the nozzle to swing through a linkage mechanism. This method has a limited range of motion, usually only able to swing at a certain angle, and cannot achieve full circular motion. In addition, the structure is complex, occupies a lot of space, and affects the aesthetics.

[0006] In summary, existing technologies struggle to produce a compact, continuously omnidirectionally rotating, non-rotating electric ring-free, and long-term underwater two-dimensional fountain device. Summary of the Invention

[0007] The purpose of this invention is to provide an omnidirectional two-dimensional fountain device without rotating electric rings and its control method, thereby solving the aforementioned problems existing in the prior art.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A non-rotating electric ring omnidirectional two-dimensional fountain device includes a nozzle assembly, a rotary joint assembly, a coaxial nested tube assembly, a horizontal drive mechanism, and a vertical drive mechanism;

[0010] The coaxial nested tube assembly includes an outer tube and an inner tube coaxially rotatably disposed inside the outer tube. The outer tube is provided with a water inlet, and the inner tube is provided with a water inlet hole that connects the inside of the outer tube and the inside of the inner tube, forming a water supply channel from the water inlet through the cavity between the outer tube and the inner tube, the water inlet hole, the inside of the inner tube to the nozzle assembly.

[0011] The rotary joint assembly includes a fixed joint and a movable joint. The fixed joint is connected to the upper end of the inner tube, and the movable joint is rotatably connected to the fixed joint. The nozzle assembly is mounted on the movable joint.

[0012] The horizontal drive mechanism is connected to the inner tube drive and is used to drive the inner tube and the fixed joint to rotate horizontally relative to the outer tube.

[0013] The vertical drive mechanism includes a vertical output shaft that passes through the interior of the inner tube and through the interior of a horizontal output shaft connected to the inner tube. The upper end of the vertical output shaft is connected to the moving joint via a transmission assembly, and is used to drive the moving joint and nozzle assembly to rotate relative to the fixed joint in a vertical plane.

[0014] Both the horizontal and vertical drive mechanisms are mounted on fixed components and do not rotate with the inner tube or moving joint.

[0015] Furthermore, the transmission assembly includes a first bevel gear and a second bevel gear that mesh with each other;

[0016] The first bevel gear is connected to the moving joint or the rotating shaft connected to the moving joint, and the second bevel gear is fixedly connected to the upper end of the vertical output shaft;

[0017] When the vertical output shaft rotates, the moving joint is driven to swing in the vertical plane through the meshing transmission of the first bevel gear and the second bevel gear.

[0018] Furthermore, it also includes a position detection component for origin reset;

[0019] The position detection component includes a first proximity switch and a second proximity switch, both of which are fixedly mounted on a stationary outer tube.

[0020] The first proximity switch is used to detect the rotational position of the moving joint in order to provide a vertical rotation origin reset signal;

[0021] The second proximity switch is used to detect the rotational position of the fixed connector or inner tube to provide a horizontal rotation origin reset signal.

[0022] Furthermore, the lower end of the inner tube is fixedly connected to the horizontal output shaft, which is rotatably supported on the base by bearings or bushings.

[0023] The vertical output shaft passes through the interior of the horizontal output shaft and is rotatably connected to the horizontal output shaft via a bushing. The vertical output shaft and the horizontal output shaft are coaxially arranged.

[0024] Furthermore, the water inlet is located in the lower end area of ​​the inner tube, and above the connection between the inner tube and the horizontal output shaft;

[0025] The outer tube is fitted over the inner tube, and a second sealing gasket and a bushing for supporting the inner tube are provided between the outer tube and the inner tube.

[0026] Furthermore, the moving joint is connected to the transmission assembly via an output shaft, and the output shaft is rotatably supported within the fixed joint via a bushing.

[0027] A first sealing gasket and a first bushing are provided between the moving joint and the fixed joint to achieve sealing during relative rotation.

[0028] A control method for the aforementioned omnidirectional two-dimensional fountain device without rotating electric rings, the device comprising a fixed outer tube and a rotatable inner tube, and a vertical output shaft passing through the interior of the inner tube, wherein a proximity switch is provided on the outer tube; the method includes:

[0029] Origin Reset Steps: Control the horizontal drive mechanism to drive the inner tube to rotate until the second proximity switch fixed on the outer tube detects that the fixed joint on the inner tube has reached the preset position, and record it as the horizontal origin; Control the vertical drive mechanism to drive the vertical output shaft to rotate, and drive the moving joint to rotate through the transmission path located inside the inner tube until the first proximity switch fixed on the outer tube detects that the moving joint has reached the preset position, and record it as the vertical origin.

[0030] Spray control steps: Start the water pump, the water flows into the inlet of the outer pipe, flows through the annular cavity between the outer pipe and the inner pipe, enters the inner pipe through the inlet at the lower end of the inner pipe, flows upward through the fixed joint and the moving joint and is sprayed out by the nozzle;

[0031] Trajectory tracking steps: Obtain the target trajectory of the nozzle, decompose it into a horizontal angle sequence and a vertical angle sequence, control the horizontal drive mechanism and the vertical drive mechanism to move synchronously, so that the nozzle points to the target position.

[0032] Furthermore, in the origin reset step, a bidirectional approximation backlash elimination algorithm is used for zero-point calibration:

[0033] When the first or second proximity switch detects the trigger signal for the first time, the corresponding drive mechanism is controlled to stop and the current position is recorded as the coarse positioning point.

[0034] The control drive mechanism is rotated in the opposite direction by a preset backlash compensation angle to eliminate gear backlash in the transmission assembly, wherein the backlash compensation angle is set according to the meshing clearance between the second bevel gear on the vertical output shaft and the first bevel gear on the moving joint.

[0035] Then, the drive mechanism is controlled to rotate back to the origin at a low speed until the proximity switch is triggered again, and the current position is recorded as the precise positioning origin.

[0036] By employing a bidirectional approximation backlash elimination algorithm, the impact of mechanical backlash caused by the long-distance transmission chain passing through the interior of the horizontal output shaft on reset accuracy is eliminated.

[0037] Furthermore, the trajectory tracking step also includes a feedforward compensation step based on the water jet reaction force:

[0038] Calculate the reaction torque generated by the water jet based on the real-time flow rate and vertical pitch angle of the nozzle;

[0039] The reaction torque is decomposed into a vertical load torque about the vertical output shaft and a horizontal torsional torque about the inner tube;

[0040] Based on the decomposed torque, feedforward compensation currents are output to the vertical drive mechanism and the horizontal drive mechanism respectively to counteract the interference of the water jet reaction force on the nozzle pointing stability.

[0041] Among them, for the coaxial structure in which the vertical output shaft passes through the inside of the inner tube, the feedforward compensation current is used to compensate for the vibration caused by the jet reaction force acting on the cantilevered moving joint.

[0042] Furthermore, in the trajectory tracking step, a path optimization algorithm based on unrestricted rotation is employed:

[0043] Find the shortest path for the nozzle to move from the current horizontal angle to the target horizontal angle;

[0044] If the direction of the shortest path is the same as the current direction of motion and passes through the horizontal origin, then determine whether the continuous rotation condition is met.

[0045] If the conditions are met, the horizontal drive mechanism drives the inner tube to rotate continuously across the origin without reversing. This utilizes the infinite rotation characteristic of the inner tube relative to the outer tube to avoid mechanical shock caused by frequent forward and reverse switching of the motor.

[0046] Meanwhile, during the rotation across the origin, the drive angle of the vertical output shaft is dynamically adjusted according to the rotation angle to compensate for the relative angle change of the transmission components caused by the horizontal rotation, thus ensuring the continuity of the vertical rotation motion.

[0047] The beneficial effects of this invention are:

[0048] High reliability without rotating electric rings: This invention fixes all drive motors on stationary components such as the base or outer tube, and transmits power to the rotating parts through a vertical output shaft passing through the inner tube and a bevel gear transmission mechanism, completely eliminating the need for rotating electric rings. This fundamentally solves the problems caused by brush wear and short circuits in water, greatly extends the service life of the device, and reduces maintenance costs.

[0049] Omnidirectional continuous rotation with strong expressive power: Since there is no limitation of cable entanglement, the horizontal drive mechanism can drive the inner tube to rotate continuously, and the vertical drive mechanism drives the moving joint to rotate continuously through the through-shaft structure. The combination of the two can realize the arbitrary direction of the nozzle on the spherical surface, which greatly enriches the water feature performance.

[0050] Compact structure and high integration: It adopts a coaxial nested tube assembly, in which the inner tube serves as both a water supply channel and a horizontal rotation transmission component; the vertical output shaft passes through the inner tube and the horizontal output shaft, cleverly utilizing the internal space to integrate the water supply channel with two sets of transmission mechanisms into one, resulting in a compact structure, small size, and easy installation and concealment.

[0051] Precise control and good stability: By setting a proximity switch on the outer tube to directly detect the position of the final actuator (moving joint and fixed joint), the influence of multi-stage transmission errors on the reset accuracy is avoided. With the help of a specific control algorithm, high-precision origin reset and trajectory tracking can be achieved. Attached Figure Description

[0052] Figure 1 This is a cross-sectional schematic diagram of the overall structure of an omnidirectional two-dimensional fountain device without rotating electric ring according to the present invention;

[0053] Figure 2 This is a flowchart illustrating the control method of the present invention.

[0054] In the attached diagram, 1-nozzle; 2-moving connector; 3-output shaft; 4-first sealing gasket; 5-first bushing; 6-fixed connector; 7-first bevel gear; 8-seventh bushing; 9-second bevel gear; 10-second sealing gasket; 11-second bushing; 12-third bushing; 13-vertical output shaft; 14-fourth bushing; 15-first proximity switch; 16-second proximity switch; 17-inner tube; 18-outer tube; 19-water inlet; 20-water inlet; 21-horizontal output shaft; 22-horizontal drive mechanism; 23-vertical drive mechanism; 24-base; 25-fifth bushing; 26-sixth bushing. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0056] like Figure 1 As shown, the non-rotating electric ring omnidirectional two-dimensional fountain device of this embodiment mainly consists of a nozzle assembly, a rotating joint assembly, a coaxial nested tube assembly, a horizontal drive mechanism 22, and a vertical drive mechanism 23.

[0057] The coaxial nested tube assembly forms the skeleton and core of the flow channel of the device. It includes an outer tube 18 and an inner tube 17. The outer tube 18, as a stationary component, is fixed to the base 24 (or connected to the water tank foundation via a flange). The inner tube 17 is coaxially fitted inside the outer tube 18 and is coaxially rotatably connected via a second bushing 11 and a third bushing 12. The outer tube 18 has a water inlet 20, which is connected to an external water supply pump. Several water inlets 19 are evenly distributed in the lower region of the inner tube 17. During operation, high-pressure water flows from the water inlet 20 into the annular cavity between the outer tube 18 and the inner tube 17, and then through the water inlets 19 into the internal channel of the inner tube 17, thus forming a water supply channel. This design integrates the flow channel and the transmission support structure into one, resulting in an extremely compact structure.

[0058] The rotary joint assembly is located at the upper end of the inner tube 17. It includes a fixed joint 6 and a movable joint 2. The fixed joint 6 is fixedly connected to the upper end of the inner tube 17 and rotates synchronously with the inner tube 17. The movable joint 2 is sleeved outside the fixed joint 6, and a relatively rotatable sealed connection is achieved through a bushing 5 and a first sealing gasket 4. The nozzle 1 is mounted on the movable joint 2.

[0059] A horizontal drive mechanism is used to achieve horizontal rotation of the nozzle. The horizontal drive mechanism 22 (preferably a combination of a stepper motor and a worm gear reducer in this embodiment) is fixedly mounted on the base 24, and its output shaft is connected to a horizontal output shaft 21. The horizontal output shaft 21 is fixedly connected to the lower end of the inner tube 17. When the horizontal drive mechanism 22 is working, it drives the horizontal output shaft 21 to rotate, thereby causing the inner tube 17, the fixed connector 6, and the moving connector 2 and nozzle 1 mounted on the fixed connector 6 to rotate as a whole around the axis, achieving horizontal orientation adjustment.

[0060] A vertical drive mechanism is used to achieve vertical rotation of the nozzle. The vertical drive mechanism 23 (preferably a combination of a stepper motor and a worm gear reducer in this embodiment) is also fixedly mounted on the base 24. Its key feature is a vertical output shaft 13. This vertical output shaft 13 passes through the internal center hole of the inner tube 17 and continues downward through the internal center hole of the horizontal output shaft 21. The upper end of the vertical output shaft 13 is connected to the moving joint 2 via a transmission assembly. Since the vertical output shaft 13 is located inside the inner tube 17, when the horizontal drive mechanism drives the inner tube 17 to rotate, the vertical output shaft 13 can remain relatively independent or follow the movement. The transmission assembly at its upper end drives the moving joint 2 to rotate relative to the fixed joint 6, thereby changing the pitch angle of the nozzle 1.

[0061] In this embodiment, both the horizontal drive mechanism 22 and the vertical drive mechanism 23 are fixed on the stationary base 24 or the outer tube 18. The power line and the signal line are directly connected without passing through any rotating conductive device, thus completely eliminating the wear and waterproofing hazards caused by the rotating electric ring.

[0062] This embodiment specifically describes a transmission assembly that uses a bevel gear transmission. It includes a first bevel gear 7 and a second bevel gear 9 that mesh with each other. The first bevel gear 7 is fixedly mounted on the output shaft 3 connected to the moving joint 2. The second bevel gear 9 is fixedly connected to the upper end of the vertical output shaft 13.

[0063] When the vertical drive mechanism 23 drives the vertical output shaft 13 to rotate, it drives the second bevel gear 9 to rotate. The second bevel gear 9 drives the first bevel gear 7, which meshes with it, to rotate. Since the axis of the first bevel gear 7 coincides with the rotation axis of the moving joint 2 and is perpendicular to the axis of the second bevel gear 9, this transmission converts the rotational motion of the vertical output shaft 13 into the oscillation of the moving joint 2 about the horizontal axis (i.e., rotation in the vertical plane), thereby precisely controlling the spray elevation angle of the nozzle 1.

[0064] This embodiment specifically describes the position detection component and its installation method. To achieve precise closed-loop control, the device is equipped with an origin reset system. This system includes a first proximity switch 15 and a second proximity switch 16.

[0065] Unlike traditional sensors mounted on rotating components, this embodiment utilizes the stationary nature of the outer tube 18, fixing both the first proximity switch 15 and the second proximity switch 16 to the inner or outer wall of the outer tube 18. The first proximity switch 15 is positioned corresponding to the sensing trigger point (such as a metal protrusion) on the moving connector 2, used to detect the vertical rotation origin of the moving connector 2. The second proximity switch 16 is positioned corresponding to the sensing trigger point on the fixed connector 6 or the inner tube 17, used to detect the horizontal rotation origin. This "stationary rotation detection" method avoids the need for wiring and power supply on the rotating component, further ensuring the integrity of the loop-free design and providing stable and reliable signal transmission.

[0066] This embodiment specifically describes the support structure of the shaft system. The lower end of the inner tube 17 is connected to the horizontal output shaft 21 by a key or fixed by a flange. The horizontal output shaft 21 is rotatably supported on the base 24 by a sixth bushing 26 (or a bearing).

[0067] The vertical output shaft 13 is a long shaft that passes through the central hole inside the horizontal output shaft 21. To ensure coaxiality and rotational independence, a fifth bushing 25 and a sixth bushing 26 are provided between the vertical output shaft 13 and the horizontal output shaft 21. This "tube-shaft" structure (i.e., the inner tube is fitted outside the vertical shaft, and the horizontal shaft is fitted outside the vertical shaft) cleverly utilizes the internal space and achieves decoupling of the two independent rotational motions, preventing them from interfering with each other.

[0068] This embodiment specifically describes the water inlet and sealing structure. The water inlet 19 is located in the lower end region of the inner tube 17 and above the connection between the inner tube 17 and the horizontal output shaft 21, ensuring that the annular cavity is filled with water before it enters the inner tube 17.

[0069] A sealing gasket 10 is provided between the outer tube 18 and the inner tube 17, located at the contact point between the upper end of the outer tube 18 and the inner tube 17, to prevent water from overflowing from the top. A second bushing 11 and a third bushing 12 are also provided, serving both a supporting function and assisting in the sealing. This arrangement ensures that the high-pressure water flow can only follow a predetermined path and will not leak into the transmission mechanism area.

[0070] This embodiment specifically describes the connection details between the moving joint and the fixed joint. The moving joint 2 is connected to the transmission assembly (first bevel gear 7) via the output shaft 3. The output shaft 3 is supported within the fixed joint 6 via the bushing 8. The mating surfaces of the moving joint 2 and the fixed joint 6 are provided with a first sealing gasket 4 and a first bushing 5. This structure ensures that the moving joint 2 can rotate flexibly relative to the fixed joint 6, while also ensuring that high-pressure water does not leak from the joint when flowing from the fixed joint 6 to the moving joint 2, achieving a perfect combination of motion transmission and fluid sealing.

[0071] Reference Figure 2 As shown, a control method for the aforementioned non-rotating electric ring omnidirectional two-dimensional fountain device, based on the same concept, is described. The device includes a fixed outer tube and a rotatable inner tube 17, and a vertical output shaft 13 passing through the interior of the inner tube 17. The outer tube 18 is equipped with a first proximity switch 15 and a second proximity switch 16. The method includes:

[0072] S1. Origin Reset Step: Control the horizontal drive mechanism to drive the inner tube 17 to rotate until the second proximity switch 16 fixed on the outer tube 18 detects that the fixed connector 6 on the inner tube 17 has reached the preset position, and record it as the horizontal origin; control the vertical drive mechanism to drive the vertical output shaft 13 to rotate, and drive the moving connector 2 to rotate through the transmission path located inside the inner tube 17 until the first proximity switch 15 fixed on the outer tube 18 detects that the moving connector 2 has reached the preset position, and record it as the vertical origin.

[0073] I. Implementation of the Horizontal Origin Reset Process

[0074] Initial state and driver startup:

[0075] The controller (such as a PLC or motion control card) sends a rotation command to the horizontal drive mechanism. The horizontal drive mechanism (usually containing a servo motor or stepper motor and a reducer) responds to the command, and its output drives the horizontal output shaft to rotate.

[0076] Motion transfer:

[0077] Because the horizontal output shaft is fixedly connected to the lower end of the inner tube, the rotation of the horizontal output shaft directly drives the inner tube to rotate around its axis inside the outer tube. At this time, the fixed connector, which is fixedly connected to the upper end of the inner tube, rotates synchronously with the inner tube. Meanwhile, the outer tube remains stationary, and the position of the second proximity switch mounted on the outer tube remains unchanged.

[0078] Position detection and signal triggering:

[0079] A sensing trigger (such as a metal protrusion or a magnet) is provided at a specific position on the fixed connector or inner tube. When the inner tube rotates, causing the fixed connector to rotate until the sensing trigger enters the sensing area of ​​the second proximity switch, the state of the second proximity switch is reversed (e.g., from open to closed), and an electrical signal is output to the controller.

[0080] Stop and record:

[0081] After detecting the trigger signal output by the second proximity switch, the controller immediately sends a stop command to the horizontal drive mechanism, which brakes, and the inner tube stops rotating. The controller records this moment as the absolute origin of the horizontal rotation. At this point, the horizontal orientation reference of the nozzle assembly is established.

[0082] II. Implementation of the Vertical Origin Reset Process

[0083] This process can be performed simultaneously with the horizontal origin reset process, or it can be performed in a time-sharing manner according to a preset sequence. The following is an example of time-sharing execution:

[0084] Driver startup:

[0085] After the horizontal origin is established (or when operating independently), the controller sends a rotation command to the vertical drive mechanism. The vertical drive mechanism (including the motor and reducer) starts, driving the vertical output shaft connected to it to rotate.

[0086] Implementation of the internal transmission path:

[0087] The vertical output shaft passes through the inner tube and the central hole inside the horizontal output shaft, extending into the fixed connector. A second bevel gear is fixedly connected to the upper end of the vertical output shaft, which meshes with the first bevel gear connected to the moving connector.

[0088] When the vertical output shaft rotates, the power is transmitted to the upper end through the shaft, and the first bevel gear is driven to rotate through the second bevel gear, which in turn drives the moving joint to rotate around the horizontal axis on the fixed joint, thereby changing the vertical pitch angle of the nozzle.

[0089] Position detection and signal triggering:

[0090] The moving connector is equipped with a specific sensing trigger. Since the outer tube remains stationary, the position of the first proximity switch, which is fixedly installed on the outer tube, remains unchanged.

[0091] When the vertical drive mechanism drives the moving joint to rotate, and the sensing trigger part on it rotates to enter the sensing area of ​​the first proximity switch, the first proximity switch is triggered and outputs an electrical signal to the controller.

[0092] Stop and record:

[0093] After receiving the trigger signal from the first proximity switch, the controller sends a stop command to the vertical drive mechanism. The vertical output shaft stops rotating, and the moving joint stops oscillating. The controller records this moment as the absolute origin of the vertical rotation. At this point, the vertical pitch reference of the nozzle assembly is established.

[0094] S2. Water spray control steps: Start the water pump, and the water flows into the inlet 20 of the outer pipe 18, flows through the annular cavity between the outer pipe 18 and the inner pipe 17, enters the inner pipe 17 through the inlet hole 19 at the lower end of the inner pipe 17, flows upward through the fixed connector 6 and the moving connector 2, and is sprayed out by the nozzle 1.

[0095] This step is triggered after the origin reset is completed or at a preset water spray time, aiming to establish a stable high-pressure water flow channel and maintain continuous water supply during nozzle rotation. The specific implementation process is as follows:

[0096] I. Pump Start-up and Water Introduction

[0097] Command triggered:

[0098] The control system sends a start command to the water pump in the water supply system, and the water pump starts to run, pressurizing the water in the water storage tank and delivering it to the input end of the device.

[0099] Entry point access:

[0100] The high-pressure water flow first reaches the inlet located on the side wall of the stationary outer pipe. Because the outer pipe is fixedly installed via a base, the inlet and the external water supply pipeline remain stationary, ensuring a reliable seal at the connection and eliminating the risk of rotational leakage.

[0101] II. Annular Cavity Flow Guiding Stage

[0102] Flow channel switching:

[0103] Water flows into the inner cavity of the outer pipe through the inlet. Because the inner pipe is coaxially fitted inside the outer pipe, the water is guided into the annular cavity formed between the inner wall of the outer pipe and the outer wall of the inner pipe.

[0104] Rotary seal protection:

[0105] At the upper and lower ends of the annular cavity, bushings (such as bushings) and sealing gaskets are respectively provided. These sealing components fill the gap between the outer and inner tubes. Although the inner tube may be rotating horizontally during water ejection, these sealing components form a dynamic sealing surface between the stationary outer tube and the rotating inner tube, preventing water from overflowing upwards or leaking downwards, forcing the water to flow only downwards along the annular cavity.

[0106] III. Internal Channel Injection Phase

[0107] Through-hole transition:

[0108] Water flows along the annular cavity until it reaches the lower end of the inner tube. Here, several water inlet holes are formed circumferentially on the inner tube wall. These water inlet holes connect the outer annular cavity with the central hole inside the inner tube.

[0109] Pressure-driven:

[0110] Under the action of fluid pressure, water flows through the inlet hole and is vertically injected into the inner central channel of the inner tube from the outer cavity of the inner tube.

[0111] IV. Upward Conveying and Ejection Stage

[0112] Internal upflow:

[0113] The water entering the inner tube is propelled upwards along the central hole of the inner tube by the continuous flow of subsequent water. Since the vertical output shaft is located inside the inner tube but is supported by a bushing (such as a bushing) and separated from the inner wall of the inner tube, the water flows around the vertical output shaft as it flows inside the inner tube, passing through the gap between the vertical output shaft and the inner tube (or a specially designed flow channel), and continues to be delivered upwards.

[0114] Via connector assembly:

[0115] The water flows to the upper end of the inner pipe and enters the internal flow channel of the fixed connector, which is fixedly connected to the top of the inner pipe. Subsequently, the water flows through the connection interface between the fixed connector and the moving connector. Here, the sealing gasket and bushing between the moving connector and the fixed connector function to ensure that the water does not leak from the rotation gap when the moving connector rotates vertically relative to the fixed connector, but is instead entirely guided into the internal flow channel of the moving connector.

[0116] Nozzle spray:

[0117] Finally, the high-pressure water flows through the internal flow channel of the moving joint and reaches the nozzle installed at the end. Under the acceleration of the nozzle's contraction, the water is ejected in the form of a high-pressure jet, forming a water column or water mist.

[0118] V. Summary of Technical Effects

[0119] Through the above steps, this invention cleverly places the flow channel inside the rotating components (inner pipe, moving joint) by utilizing a path design of "water inlet in outer pipe, water flow through inner pipe, and water spraying from the joint." Throughout the process, the water flow smoothly transitions from the stationary component (outer pipe) to the rotating component (inner pipe, moving joint), and all dynamic sealing links (between the outer and inner pipes, and between the fixed and moving joints) employ mechanical seal structures, preventing contact between electrical components and the fluid, thus achieving continuous and reliable water spraying under two-dimensional omnidirectional rotational motion.

[0120] S3. Trajectory tracking steps: Obtain the target trajectory of nozzle 1, decompose it into a horizontal angle sequence and a vertical angle sequence, control the horizontal drive mechanism and the vertical drive mechanism to move synchronously, so that nozzle (1) points to the target position.

[0121] This step is performed concurrently with the water spray control step, aiming to enable the nozzle to accurately trace a preset spatial trajectory by coordinating the horizontal and vertical movements in real time. The specific implementation process is as follows:

[0122] I. Target Trajectory Acquisition and Preprocessing

[0123] Data reading:

[0124] The controller (such as an industrial control computer or an embedded motion control unit) receives the target trajectory of the nozzle from the host computer (computer host or console). This target trajectory is usually defined as a sequence of continuous position points of the nozzle in a three-dimensional coordinate system, or as a set of continuous functions with respect to time t.

[0125] Inverse kinematics:

[0126] The controller's internal kinematic algorithm module performs inverse kinematic transformation on the read target trajectory data. Since the nozzle's direction is determined by both the horizontal rotation angle (azimuth) and the vertical rotation angle (pitch), the controller calculates each spatial target position point (X,Y,Z) into the corresponding mechanical rotation angle command, i.e., the horizontal target angle value and the vertical target angle value, based on the preset mechanical structure geometric parameters.

[0127] II. Trajectory Discretization and Angle Sequence Generation

[0128] Time-division interpolation:

[0129] Since the controller is a digital system and cannot output a continuous analog curve, it employs a time-division interpolation algorithm. The entire motion time is divided into several small, equally spaced control cycles (e.g., one cycle every 10 milliseconds).

[0130] Sequence generation:

[0131] At the start of each control cycle, the controller calculates the horizontal and vertical angles that the nozzle should reach within the current cycle based on the inverse calculation results described above. This decomposes the continuous target trajectory into two discrete time-angle-direction sequences: one is a time-varying horizontal angle-direction sequence, and the other is a time-varying vertical angle-direction sequence. These two sequences correspond strictly to each other on the time axis, ensuring the synchronization of subsequent actions.

[0132] III. Synchronous Action Execution of the Drive Mechanism

[0133] Horizontal motion execution:

[0134] The horizontal drive mechanism receives control commands and drives the horizontal output shaft to rotate. This rotation is transmitted to the inner tube via a mechanical connection, causing the inner tube and the fixed connector attached to it to rotate around the vertical axis, thereby changing the horizontal azimuth angle of the nozzle and bringing it closer to the target value in the horizontal angle sequence.

[0135] Vertical motion execution:

[0136] Synchronized with the horizontal movement, the vertical drive mechanism receives control commands and drives the vertical output shaft to rotate. This rotation passes through the inside of the inner tube and is transmitted in reverse direction via the upper bevel gear transmission assembly (first bevel gear and second bevel gear), driving the moving joint to swing relative to the fixed joint around the horizontal axis, thereby changing the vertical pitch angle of the nozzle and bringing it closer to the target value in the vertical angle sequence.

[0137] Dynamic tracking loop:

[0138] The aforementioned control cycle is executed continuously. Within each cycle, the controller recalculates the target angle, compares the error, and adjusts the output. Through this high-frequency cyclic control, the horizontal drive mechanism and the vertical drive mechanism maintain a strict synchronous coordination relationship in time, ensuring that the direction resulting from the combined horizontal and vertical rotational motions of the nozzle always tracks the spatial curve of the target trajectory in real time.

[0139] IV. Summary of Technical Effects

[0140] Through the above steps, this invention achieves complex spatial trajectory tracking. The key lies in utilizing the controller's high-frequency interpolation calculations to decompose the complex spatial trajectory into two single-degree-of-freedom angle sequences. Furthermore, through the independent and synchronous execution of "tube rotation" and "axis rotation" at the hardware level, precise motion control of the nozzle on the spherical surface is achieved. This process incorporates closed-loop feedback control, eliminating the influence of mechanical transmission errors and water flow interference, ensuring the accuracy and smoothness of the water feature performance.

[0141] S4. In the origin reset step, a bidirectional approximation gap elimination algorithm is used for zero-point calibration.

[0142] When the first proximity switch 15 or the second proximity switch 16 detects the trigger signal for the first time, the corresponding drive mechanism is controlled to stop and the current position is recorded as the coarse positioning point.

[0143] The control drive mechanism is rotated in the opposite direction by a preset clearance compensation angle to eliminate gear backlash in the transmission assembly. The clearance compensation angle is set according to the meshing clearance between the second bevel gear 9 on the vertical output shaft 13 and the first bevel gear 7 on the moving joint 2.

[0144] Then, the drive mechanism is controlled to rotate back to the origin at a low speed until the proximity switch is triggered again, and the current position is recorded as the precise positioning origin.

[0145] The two-way approximation backlash elimination algorithm eliminates the impact of mechanical backlash caused by the long-distance transmission chain passing through the interior of the horizontal output shaft 21 on the reset accuracy.

[0146] This step is an optimized implementation of the origin reset step, aiming to solve the positioning error problem caused by long transmission chains and bevel gear meshing clearance. The specific implementation process is as follows:

[0147] I. High-speed coarse positioning stage

[0148] Drive control:

[0149] The controller sends motion commands to the target drive mechanism (horizontal or vertical), which drives the mechanical components to rotate at a first preset speed (higher speed). In the vertical direction, the vertical drive mechanism drives the vertical output shaft to rotate, which in turn drives the moving joint to rotate via the transmission assembly; in the horizontal direction, the horizontal drive mechanism drives the inner tube to rotate.

[0150] Triggering and stopping:

[0151] When the sensing trigger on the moving part (moving or stationary joint) enters the sensing area of ​​the proximity switch (first or second proximity switch), the proximity switch outputs a trigger signal. Upon detecting this signal, the controller immediately stops the drive mechanism. At this time, the mechanical transmission chain is under tension, but due to inertia and braking delay, the recorded position may be deviated, and the meshing tooth surfaces of the gears may be in contact on one side. The controller records the encoder's position data at this moment as the "coarse positioning point."

[0152] II. Reverse backlash compensation stage

[0153] Parameter retrieval:

[0154] The controller retrieves the preset "backlash compensation angle" from the storage unit. This parameter is set based on the mechanical structural characteristics of the device, specifically calculated from the meshing backlash between the second bevel gear on the vertical output shaft and the first bevel gear on the moving joint, as well as the cumulative backlash in the long transmission chain. This angle value is usually set slightly larger than the angle value corresponding to the theoretical backlash.

[0155] Reverse rotation execution:

[0156] The controller controls the drive mechanism to perform a reverse rotation. The drive mechanism drives the transmission shaft to rotate in the opposite direction by the preset backlash compensation angle.

[0157] During this process, the initially contacting gear teeth quickly disengage, traversing the tooth gap until they contact the mating gear on the other side of the tooth profile. Because the vertical output shaft passes through the long transmission structure inside the horizontal output shaft, this reverse action effectively releases the elastic deformation stress in the transmission chain and ensures that the gear meshing surfaces switch to a reverse contact state. At this point, the mechanical system is in a "free" or "reverse preload" state, eliminating any potential misalignment that may exist during unidirectional approach.

[0158] III. Low-speed precision positioning stage

[0159] Low-speed approximation:

[0160] After completing the reverse backlash elimination, the controller controls the drive mechanism to rotate again towards the origin (forward) at a second preset speed (a low speed significantly lower than the first preset speed).

[0161] Since the backlash is eliminated, the rotational motion is directly converted into the precise angular displacement of the moving joint or inner tube, and there is no backlash error.

[0162] Precise positioning:

[0163] When the drive mechanism drives the component to rotate again, causing the proximity switch to detect the trigger signal again, the position of the mechanical component now precisely corresponds to the position of the sensor. The controller records the encoder's position data at this moment as the "precise positioning origin" and sets this position as the system's absolute zero point.

[0164] IV. Summary of Technical Effects

[0165] Through the above steps, this invention overcomes the problem of large mechanical backlash caused by the long transmission chain formed by the vertical output shaft passing through the interior of the horizontal output shaft. Traditional unidirectional zero-return can lead to inconsistent zero-return positions due to the presence of backlash (the zero-return position may fluctuate within the backlash range each time). This embodiment adopts a bidirectional approximation logic of "forward coarse positioning - reverse backlash elimination - forward fine positioning," which forcibly eliminates the influence of gear backlash on positioning, ensures the repeatability of positioning accuracy for each origin reset, and provides a high-precision coordinate reference for subsequent trajectory tracking control.

[0166] In this embodiment, the trajectory tracking step further includes a feedforward compensation step based on the water jet reaction force:

[0167] Calculate the reaction torque generated by the water jet based on the real-time flow rate and vertical pitch angle of nozzle 1;

[0168] The reaction torque is decomposed into a vertical load torque about the vertical output shaft 13 and a horizontal torsional torque about the inner tube 17;

[0169] Based on the decomposed torque, feedforward compensation currents are output to the vertical drive mechanism and the horizontal drive mechanism respectively to counteract the interference of the water jet reaction force on the pointing stability of nozzle 1.

[0170] Among them, for the coaxial structure in which the vertical output shaft 13 passes through the inner tube 17, the feedforward compensation current is used to compensate for the vibration caused by the jet reaction force acting on the cantilevered moving joint 2.

[0171] In this embodiment, a path optimization algorithm based on unrestricted rotation is used in the trajectory tracking step:

[0172] Find the shortest path for nozzle 1 to move from the current horizontal angle to the target horizontal angle;

[0173] If the direction of the shortest path is the same as the current direction of motion and passes through the horizontal origin, then determine whether the continuous rotation condition is met.

[0174] If the conditions are met, the horizontal drive mechanism drives the inner tube 17 to rotate continuously across the origin without reversing. By utilizing the infinite rotation characteristic of the inner tube 17 relative to the outer tube 18, the mechanical impact caused by frequent forward and reverse switching of the motor is avoided.

[0175] Meanwhile, during the rotation across the origin, the driving angle of the vertical output shaft (13) is dynamically adjusted according to the rotation angle to compensate for the relative angle change of the transmission components caused by the horizontal rotation, and to ensure the continuity of the vertical rotation motion.

[0176] This embodiment describes the control logic in detail. The controller (such as a PLC or motion control card) executes the program stored in the memory to achieve the following steps:

[0177] After the device is powered on, the controller first executes the reset procedure. The horizontal drive mechanism 22 drives the inner tube 17 to rotate at a low speed until the second proximity switch 16 is triggered, and the horizontal origin is recorded. The vertical drive mechanism 23 drives the vertical output shaft 13 to rotate until the first proximity switch 15 is triggered, and the vertical origin is recorded. Preferably, a bidirectional approximation backlash elimination algorithm is used: first, it quickly approaches the trigger point and stops; then it rotates in the opposite direction by a compensation angle (eliminating bevel gear backlash); then it approaches the trigger point at a low speed. This method eliminates backlash errors in the long transmission chain and ensures zero-point accuracy.

[0178] Spray control:

[0179] The controller sends a command to start the water pump, and the water flows out from nozzle 1 along the path described above.

[0180] Trajectory tracking and optimization

[0181] The controller receives the target trajectory sent by the host computer.

[0182] Feedforward compensation: The controller calculates the disturbance torque generated by the reaction force of the water jet in real time based on the current flow rate and nozzle angle, and adds it to the drive current of the motor to actively compensate for the shaking caused by the water flow impact, especially for the stable control of the cantilevered moving joint 2.

[0183] 1. Bidirectional Approximation Backlash Elimination Algorithm

[0184] Definition: This is a precision positioning control algorithm used in the origin reset (zeroing) process of a fountain device. It eliminates the influence of gear backlash (reverse backlash elimination) in the mechanical transmission chain on positioning accuracy through a specific sequence of actions: "forward coarse positioning—reverse backlash elimination—forward fine positioning."

[0185] Specific implementation steps:

[0186] Forward coarse positioning: The control drive mechanism rotates rapidly and stops when the proximity switch detects the trigger signal for the first time. The current position is recorded as the "coarse positioning point".

[0187] Reverse backlash elimination: Controls the drive mechanism to rotate in the opposite direction by a preset "backlash compensation angle". This action aims to disengage the gear meshing surfaces and cross the tooth gap, eliminating elastic deformation and mechanical play in the transmission chain (especially long-distance drive shafts).

[0188] Forward precision positioning: Control the drive mechanism to rotate back to the origin at a low speed until the proximity switch is triggered again, and record the position at this time as the "precise positioning origin".

[0189] Core function:

[0190] This addresses the mechanical backlash caused by the long transmission chain formed when the vertical output shaft passes through the interior of the horizontal output shaft, ensuring consistent positioning accuracy for each origin reset and preventing fluctuations in the zero-return position due to the presence of backlash.

[0191] 2. Hydrodynamic feedforward compensation control method

[0192] Definition: This is an active anti-interference control method used in the trajectory tracking process of a fountain device. Based on the reaction force characteristics generated by the water jet, it pre-calculates and outputs a compensation current to the drive motor to counteract the interference caused by the water flow impact.

[0193] Specific implementation principle:

[0194] Calculate reaction torque: The system calculates the reaction torque generated when the water jet is sprayed in real time based on the real-time flow rate and vertical pitch angle of the nozzle.

[0195] Torque decomposition: The calculated reaction torque is decomposed into two components:

[0196] The vertical load torque acting on the vertical output shaft (affects nozzle pitch stability).

[0197] The horizontal torsional moment acting on the inner tube (affects the horizontal orientation stability of the nozzle).

[0198] Feedforward compensation: Based on the decomposed torque value, additional "feedforward compensation current" is output to the vertical drive mechanism and the horizontal drive mechanism respectively.

[0199] Core function:

[0200] It counteracts the interference of the water jet reaction force on the nozzle pointing stability, especially compensates for the vibration caused by the jet reaction force acting on the cantilevered moving joint, thereby ensuring the trajectory tracking accuracy and motion stability of the fountain when spraying at high speed and high flow rate.

[0201] Working principle of the invention

[0202] The working principle of this invention is based on the coaxial nested transmission decoupling principle and the static sealed water circuit transmission principle, as detailed below:

[0203] 1. Mechanical transmission decoupling principle:

[0204] This invention decouples two orthogonal rotational motions in space (horizontal rotation and vertical rotation) through a clever coaxial structure.

[0205] Horizontal rotation is achieved by rotating the outer tube (inner tube 17), and the transmission chain is "horizontal motor → horizontal output shaft → inner tube → fixed connector → nozzle assembly".

[0206] Vertical rotation is achieved by rotating an internal shaft (vertical output shaft 13), and the transmission chain is "vertical motor → vertical output shaft → bevel gear set → moving joint → nozzle pitch".

[0207] Since the vertical output shaft 13 passes through the interior of the inner tube 17 and the horizontal output shaft 21, when the inner tube 17 rotates horizontally, the internal vertical output shaft 13 can rotate independently or remain stationary. This free combination of "tube rotates but shaft does not rotate" or "tube and shaft rotate together" achieves complete independence of the two movements in the mechanical structure, without interference between them, thus enabling the nozzle to point arbitrarily on the spherical surface.

[0208] 2. Principle of static seal-based fluid transfer:

[0209] In traditional fountain devices, rotating components require water supply and often employ rotary seals or rotary joints, which are prone to leakage. This invention designs the flow channel within an annular cavity of an outer pipe and an inner pipe. The outer pipe 18 is stationary, and the inlet 20 connects to the stationary water pipe. Water flows into the stationary outer pipe 18 and then through the inlet 19 into the rotating inner pipe 17. Since the inner pipe 17 rotates, relative motion exists here. However, this invention, through a reasonable arrangement of bushings and gaskets, places the rotary sealing surface in an area with low pressure or controllable flow velocity, and employs relative rotation sealing technology at key sealing points (such as between the fixed and moving joints). More importantly, by eliminating the rotating electric ring, all cables do not need to pass through the rotating surface, allowing the entire flow channel to be designed as a single, sealed container, greatly improving waterproofing and operational reliability.

[0210] 3. Absolute position detection principle:

[0211] This invention utilizes the stationary nature of the outer tube 18 to fix the position sensor (proximity switch) on a stationary reference frame, directly detecting the position of rotating components (moving joint and fixed joint). This constitutes a detection mechanism based on an absolute coordinate system. Compared to installing an encoder at the motor end (which requires calculating the end position through the transmission chain), the detection method of this invention eliminates transmission errors and, combined with a backlash-eliminating control algorithm, achieves high-precision position control.

[0212] By adopting the above-disclosed technical solution of this invention, the following beneficial effects are obtained:

[0213] 1. It completely solves the problems of wear and waterproofing of rotating electric rings, significantly improving the reliability and service life of the device.

[0214] This invention eliminates the rotating slip ring (conductive slip ring) indispensable in traditional two-dimensional fountain devices. By employing a special transmission structure combining a "coaxial nested tube assembly" with a "vertical output shaft passing through the interior of the horizontal output shaft," both the horizontal and vertical drive mechanisms are fixedly mounted on a stationary base or outer tube. The power and control signal lines do not need to follow the rotating components, thus completely eliminating the risk of poor contact due to brush wear and short circuits caused by the underwater environment. This achieves true "slip ring-free" operation, significantly reducing maintenance frequency and costs, and making it suitable for long-term continuous underwater operation.

[0215] 2. It achieves true omnidirectional continuous rotation, greatly enriching the expressiveness of water feature performances.

[0216] Existing non-rotating electric ring superposition schemes are typically limited by cable entanglement issues, allowing only reciprocating oscillations and preventing continuous rotation. This invention, by eliminating the rotating electric ring and removing the cable entanglement limitation, enables both the inner tube (horizontal rotating component) and the moving joint (vertical rotating component) to achieve continuous 360° infinite rotation. The superposition of horizontal and vertical rotations allows the nozzle to point to any position on the spherical surface and perform complex continuous trajectory movements (such as spirals or continuous circles), breaking through the motion limitations of traditional nozzles.

[0217] 3. Compact structure and high integration, easy to install and conceal.

[0218] This invention cleverly utilizes the design concepts of "pipe within a pipe" and "axis within an axis." The inner pipe serves as both a horizontally rotating transmission component and its internal space as a channel for the vertical output shaft; the cavity between the inner and outer pipes acts as a water supply channel, while the interior serves as a vertical transmission channel. This design highly integrates the water supply channel, horizontal rotation mechanism, and vertical rotation mechanism into a coaxial, integrated structure. Its small size and regular shape not only reduce space requirements but also facilitate concealed installation in landscape ponds, enhancing the overall aesthetic appeal of the landscape.

[0219] 4. High origin reset accuracy and good control stability.

[0220] This invention employs a "stationary sensor detecting rotating components" design, fixing the proximity switch to the stationary outer tube to directly detect the positions of the moving and stationary joints. This detection method avoids the impact of transmission chain errors on reset accuracy and achieves direct position feedback to the final actuator. Combined with a unique bidirectional approximation backlash elimination algorithm and hydrodynamic feedforward compensation control method, it effectively eliminates the interference caused by the mechanical backlash of the long transmission chain and the reaction force of the water jet, ensuring the pointing accuracy and stability of the nozzle during high-speed, complex movements.

[0221] 5. Excellent sealing performance and easy maintenance.

[0222] The main sealing points of the device are all located between relatively rotating components (such as between the inner and outer tubes, and between the moving and fixed joints). Through a reasonable layout of gaskets and bushings, a good dynamic sealing effect is achieved. Since there are no easily damaged electro-ring components and the main mechanical structure is robust and durable, the device has strong overall weather resistance, adapts to complex underwater working environments, and greatly extends the equipment's trouble-free operating time.

[0223] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A non-rotating electric ring omnidirectional two-dimensional fountain device, characterized in that, Includes nozzle assembly, rotary joint assembly, coaxial nested tube assembly, horizontal drive mechanism and vertical drive mechanism; The coaxial nested tube assembly includes an outer tube (18) and an inner tube (17) coaxially rotatably disposed inside the outer tube (18). The outer tube (18) is provided with a water inlet (20), and the inner tube (17) is provided with a water inlet hole (19) connecting the inside of the outer tube (18) and the inside of the inner tube (17), forming a water supply channel from the water inlet (20) through the cavity between the outer tube (18) and the inner tube (17), the water inlet hole (19), the inside of the inner tube (17) to the nozzle assembly; The rotating joint assembly includes a fixed joint (6) and a movable joint (2). The fixed joint (6) is connected to the upper end of the inner tube (17). The movable joint (2) is rotatably connected to the fixed joint (6). The nozzle assembly is mounted on the movable joint (2). The horizontal drive mechanism is connected to the inner tube (17) for driving the inner tube (17) and the fixed joint (6) to rotate horizontally relative to the outer tube (18); The vertical drive mechanism includes a vertical output shaft (13), which passes through the interior of the inner tube (17) and through the interior of the horizontal output shaft (21) connected to the inner tube (17). The upper end of the vertical output shaft (13) is connected to the moving joint (2) via a transmission assembly, and is used to drive the moving joint (2) and the nozzle assembly to rotate relative to the fixed joint (6) in the vertical plane. Both the horizontal drive mechanism and the vertical drive mechanism are mounted on a fixed component and do not rotate with the inner tube (17) or the moving joint (2).

2. The omnidirectional two-dimensional fountain device without rotating electric ring according to claim 1, characterized in that, The transmission assembly includes a first bevel gear (7) and a second bevel gear (9) that mesh with each other; The first bevel gear (7) is connected to the moving joint (2) or the rotating shaft connected to the moving joint (2), and the second bevel gear (9) is fixedly connected to the upper end of the vertical output shaft (13); When the vertical output shaft (13) rotates, the moving joint (2) is driven to swing in the vertical plane through the meshing transmission of the first bevel gear (7) and the second bevel gear (9).

3. The omnidirectional two-dimensional fountain device without rotating electric ring according to claim 1, characterized in that, It also includes a position detection component for origin reset; The position detection component includes a first proximity switch (15) and a second proximity switch (16), both of which are fixedly mounted on the stationary outer tube (18). The first proximity switch (15) is used to detect the rotational position of the moving joint (2) to provide a vertical rotation origin reset signal; The second proximity switch (16) is used to detect the rotational position of the fixed connector (6) or the inner tube (17) to provide a horizontal rotation origin reset signal.

4. The omnidirectional two-dimensional fountain device without rotating electric ring according to claim 1, characterized in that, The lower end of the inner tube (17) is fixedly connected to the horizontal output shaft (21), and the horizontal output shaft (21) is rotatably supported on the base (24) by bearings or bushings (26). The vertical output shaft (13) passes through the interior of the horizontal output shaft (21) and is rotatably connected to the horizontal output shaft (21) through bushings (25, 26). The vertical output shaft (13) and the horizontal output shaft (21) are coaxially arranged.

5. The omnidirectional two-dimensional fountain device without rotating electric ring according to claim 1, characterized in that, The water inlet (19) is located in the lower end region of the inner tube (17) and above the connection between the inner tube (17) and the horizontal output shaft (21); The outer tube (18) is sleeved on the outside of the inner tube (17), and a second sealing gasket (10) and a bushing (11, 12) for supporting the inner tube (17) are provided between the outer tube (18) and the inner tube (17).

6. The omnidirectional two-dimensional fountain device without rotating electric ring according to claim 1, characterized in that, The moving joint (2) is connected to the transmission assembly via the output shaft (3), and the output shaft (3) is rotatably supported in the fixed joint (6) via the bushing (8); A first sealing gasket (4) and a first bushing (5) are provided between the moving joint (2) and the fixed joint (6) to achieve sealing during relative rotation.

7. A control method for an omnidirectional two-dimensional fountain device without rotating electric rings as described in any one of claims 1 to 6, characterized in that, The device includes a fixed outer tube (18) and a rotatable inner tube (17), and a vertical output shaft (13) passing through the interior of the inner tube (17). Proximity switches (15, 16) are provided on the outer tube (18). The method includes: Origin Reset Steps: Control the horizontal drive mechanism to drive the inner tube (17) to rotate until the second proximity switch (16) fixed on the outer tube (18) detects that the fixed connector (6) on the inner tube (17) has reached the preset position, and record it as the horizontal origin; Control the vertical drive mechanism to drive the vertical output shaft (13) to rotate, and drive the moving connector (2) to rotate through the transmission path located inside the inner tube (17) until the first proximity switch (15) fixed on the outer tube (18) detects that the moving connector (2) has reached the preset position, and record it as the vertical origin; Spraying control steps: Start the water pump, and the water flows into the inlet (20) of the outer pipe (18), flows through the annular cavity between the outer pipe (18) and the inner pipe (17), enters the inner pipe (17) through the inlet hole (19) at the lower end of the inner pipe (17), flows upward through the fixed connector (6) and the moving connector (2) and is sprayed out by the nozzle (1); Trajectory tracking steps: Obtain the target trajectory of the nozzle (1), decompose it into a horizontal angle sequence and a vertical angle sequence, control the horizontal drive mechanism and the vertical drive mechanism to move synchronously, so that the nozzle (1) points to the target position.

8. The control method according to claim 7, characterized in that, In the origin reset step, a bidirectional approximation gap elimination algorithm is used for zero-point calibration: When the first proximity switch (15) or the second proximity switch (16) detects the trigger signal for the first time, the corresponding drive mechanism is controlled to stop and the current position is recorded as a coarse positioning point; The drive mechanism is controlled to rotate in the opposite direction by a preset clearance compensation angle to eliminate gear backlash in the transmission assembly, wherein the clearance compensation angle is set according to the meshing clearance between the second bevel gear (9) on the vertical output shaft (13) and the first bevel gear (7) on the moving joint (2); Then, the drive mechanism is controlled to rotate back to the origin at a low speed until the proximity switch is triggered again, and the current position is recorded as the precise positioning origin. The bidirectional approximation backlash elimination algorithm eliminates the impact of mechanical backlash caused by the long-distance transmission chain through which the vertical output shaft (13) passes through the horizontal output shaft (21) on the reset accuracy.

9. The control method according to claim 7, characterized in that, The trajectory tracking step also includes a feedforward compensation step based on the water jet reaction force: Calculate the reaction torque generated by the water jet based on the real-time flow rate and vertical pitch angle of the nozzle (1); The reaction torque is decomposed into a vertical load torque on the vertical output shaft (13) and a horizontal torsional torque on the inner tube (17); Based on the decomposed torque, feedforward compensation currents are output to the vertical drive mechanism and the horizontal drive mechanism respectively to counteract the interference of the water jet reaction force on the pointing stability of the nozzle (1). Among them, for the coaxial structure through which the vertical output shaft (13) passes through the inner tube (17), the feedforward compensation current is used to compensate for the vibration caused by the jet reaction force acting on the cantilevered moving joint (2).

10. The control method according to claim 7, characterized in that, In the trajectory tracking step, a path optimization algorithm based on unrestricted rotation is employed: Obtain the shortest path for nozzle (1) to move from the current horizontal angle to the target horizontal angle; If the direction of the shortest path is consistent with the current direction of motion and passes through the horizontal origin, then determine whether the continuous rotation condition is met. If satisfied, the horizontal drive mechanism is controlled to drive the inner tube (17) to rotate continuously across the origin without reversing. The infinite rotation characteristic of the inner tube (17) relative to the outer tube (18) is utilized to avoid mechanical shock caused by frequent forward and reverse switching of the motor. Meanwhile, during the rotation across the origin, the driving angle of the vertical output shaft (13) is dynamically adjusted according to the rotation angle to compensate for the relative angle change of the transmission components caused by the horizontal rotation, and to ensure the continuity of the vertical rotation motion.

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