Reverse self-locking speed reduction driving device

Abstract

The invention relates to the technical field of photovoltaic tracking driving, and provides a reverse self-locking speed reduction driving device which comprises a transmission shaft, a shell, a first gear, two output shafts and a third gear, the two output shafts are symmetrically installed at the two ends of the transmission shaft, the output shafts are coaxial with the axis of the transmission shaft, the first gear is eccentrically installed on the transmission shaft, and the second gear is eccentrically installed on the shell. Comprising a first gear and a second gear which are different in tooth number, a second gear meshed with the first gear is formed on each output shaft, a third gear is eccentrically meshed with the second gear, and the eccentric directions of the two first gears meshed with the two output shafts are conjugated. Large reduction ratio output can be achieved through two-stage speed reduction, multi-tooth meshing bearing is achieved through cooperation of arc teeth, the bearing torque is increased, sliding friction transmission is adopted between teeth, and reverse large-torque self-locking of the output shaft is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic tracking drive technology, and in particular to a reverse self-locking deceleration drive device. Background Art

[0002] Heavy-load applications such as photovoltaic tracking systems place stringent demands on the performance of reducers. Traditional reducers suffer from insufficient holding torque and weak impact resistance when operating in extreme conditions such as high winds. Photovoltaic tracking systems require a drive mechanism with extremely high reverse self-locking and shock load resistance, while also meeting the requirements of low-speed, intermittent motion. Existing reducers struggle to meet the reliability requirements for 25 years of continuous outdoor operation in terms of compactness, reverse self-locking load retention, and service life. Especially in high wind conditions, the need to both overcome the weight of the components during normal operation and achieve short-term continuous operation under peak wind torque poses new challenges to the reducer's gear meshing, torque transmission path, and overall structural strength. When tracking systems encounter extreme wind conditions, the tracker is affected by the uneven distribution of wind loads, and the resulting torque is entirely borne by the reducer mechanism. Commercially available tracking mechanisms often use a worm gear reducer as the reduction drive. Since the worm gear reducer uses involute teeth and is limited by its size, when it is subjected to reverse torque caused by strong winds, each tooth has to bear a huge tangential load. Tracking bracket failures caused by tooth root fracture often occur in actual projects.

[0003] Therefore, a reversible self-locking reduction drive device is proposed. Summary of the Invention

[0004] The purpose of the present invention is to provide a reversible self-locking reduction drive device with the advantages of high reverse self-locking ability, high torque output capacity, excellent compact structure, larger reduction ratio, adaptability to intermittent motion and resistance to impact loads.

[0005] To achieve the above object, the present invention adopts the following technical solutions: According to an embodiment of the present invention, a reversible self-locking reduction drive device includes: a transmission shaft, a housing, a first gear and two output shafts, and a third gear integrally arranged with the housing, the housing is provided with a mounting cavity extending along a horizontal direction, the transmission shaft is installed in the mounting cavity and extends along the penetration direction, the two output shafts are symmetrically installed at both ends of the transmission shaft, and the output shaft is coaxial with the axis of the transmission shaft, the first gear is eccentrically installed on the transmission shaft, the first gear is configured as an arc tooth external gear, including gear one and gear two with different numbers of teeth, a second gear is formed on the output shaft that meshes with gear one, the third gear is eccentrically meshed with gear two, the second gear and the third gear are configured as arc tooth internal gears, and the eccentric directions of the two first gears meshing with the two output shafts are conjugated.

[0006] The reversibly self-locking reduction drive device according to an embodiment of the present invention achieves a higher reduction ratio output through two-stage reduction. The design and application of circular arc teeth enable multi-tooth meshing load-bearing, increasing torque and impact load resistance. Direct sliding friction transmission between teeth enables reverse high-torque self-locking of the output shaft. This reduction drive device, applied to the drive structure of a photovoltaic tracking bracket, can achieve higher torque output and reverse torque retention in low-speed, intermittent motion environments, offering significant advantages in adapting to harsher operating conditions such as high winds.

[0007] In addition, the reversible self-locking deceleration drive device according to the above embodiment of the present invention may also have the following additional technical features: In some embodiments of the present invention, the circular arc tooth external gear includes a cycloid surface of the external tooth, a transition surface of the external tooth, and a tooth top surface of the external tooth. The cycloid surface of the external tooth is determined by a curve generation equation. The tooth top surface of the external tooth is set as a plane. The transition surface of the external tooth connects the cycloid surface of the external tooth and the tooth top surface of the external tooth and smoothly connects the cycloid surface of the external tooth and the tooth top surface of the external tooth. The curve generation equation of the cycloid surface of the external tooth is as follows: ; Wherein, X is the X-axis coordinate on the curve; Y is the Y-axis coordinate on the curve; e is the eccentricity; α is the angle, ranging from 0 to 360 degrees; Z1 is the number of teeth of the internal gear meshing with the external gear; and R1 is the pitch radius of the internal gear.

[0008] In some embodiments of the present invention, the circular arc tooth internal gear includes an arc surface of the internal teeth, a meshing surface of the internal teeth and a transition surface of the internal teeth. The transition surface of the internal teeth is a smooth transition surface connecting two adjacent meshing surfaces of the internal teeth. Only a part of the transition surface of the internal teeth participates in the meshing with the external teeth. The meshing surface of the internal teeth is formed by the motion fitting of the cycloid surface of the external teeth and smoothly transitions to the circular arc surface of the internal teeth. In order to increase the meshing contact area, reduce local contact stress and improve the stability of reverse self-locking, the circular arc surface of the internal teeth is composed of arc surfaces with equal curvature radius, ensuring multi-point contact with the external teeth, and the number of teeth meshing at the same time at any rotation angle is not less than 3 teeth. The circular arc tooth external gear and the circular arc tooth internal gear are sliding friction.

[0009] In some embodiments of the present invention, the number of internal teeth of the second gear is greater than the number of teeth of the gear one, the number of internal teeth of the third gear is greater than the number of teeth of the gear two, and the difference in the number of teeth between the circular arc tooth internal gear and the circular arc tooth external gear is 1 tooth, and the difference in the number of teeth between the second gear and the third gear is 1 to 2 teeth.

[0010] In some embodiments of the present invention, a fourth gear is further included. The fourth gear is installed in the housing and fixedly installed on the transmission shaft between the two first gears. The fourth gear drives the transmission shaft to rotate.

[0011] In some embodiments of the present invention, a power piece is further included, which is installed on the shell. The shell is provided with a through hole connected to the installation cavity. A fifth gear is fixedly installed on the output end of the power piece, and the fifth gear passes through the through hole to transmit torque to the fourth gear.

[0012] In some embodiments of the present invention, a bracket and a sixth gear are further included. The bracket is mounted on the inner wall of the shell and is located between the two first gears. The sixth gear is mounted on the bracket and is respectively engaged with the fourth gear and the fifth gear.

[0013] In some embodiments of the present invention, a rotating shaft is further included, wherein the rotating shaft is mounted on the bracket, and the sixth gear is rotatably mounted on the rotating shaft.

[0014] In some embodiments of the present invention, further comprising: a first fixing member, the first fixing member being installed between the fourth gear and the transmission shaft to fix the fourth gear on the transmission shaft; a second fixing member, the second fixing member being installed between the transmission shaft and the first bearing, and fixing the inner ring of the first bearing on the transmission shaft; A third fixing member is installed between the output end of the power member and the fifth gear, and fixes the fifth gear on the output end of the power member.

[0015] In some embodiments of the present invention, further comprising: a first bearing, wherein the first bearing is mounted on the transmission shaft, and the first gear is mounted on the transmission shaft via the first bearing; a second bearing, the second bearing being mounted on the output shaft and disposed close to an end portion of the transmission shaft, wherein an inner ring of the second bearing cooperates with the transmission shaft to provide radial support for the transmission shaft; A composite sleeve is installed in the housing, and the inner ring of the composite sleeve cooperates with the outer ring of the output shaft to radially support the output shaft.

[0016] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of a reversible self-locking speed reduction drive device according to an embodiment of the present invention; Figure 2 The structure of the reverse self-locking deceleration drive device of the embodiment of the present invention is shown as follows Figure 1 ; Figure 3 The structure of the reverse self-locking deceleration drive device of the embodiment of the present invention is shown as follows Figure 2 ; Figure 4 The structure of the reverse self-locking deceleration drive device of the embodiment of the present invention is shown as follows Figure 3 ; Figure 5 The structure of the reverse self-locking deceleration drive device of the embodiment of the present invention is shown as follows Figure 4 ; Figure 6 The structure of the reverse self-locking deceleration drive device of the embodiment of the present invention is shown as follows Figure 5 ; Figure 7 Schematic diagram of the circular arc gear structure of the reversible self-locking reduction drive device according to an embodiment of the present invention Figure 1 ; Figure 8 Schematic diagram of the circular arc gear structure of the reversible self-locking reduction drive device according to an embodiment of the present invention Figure 2 .

[0018] Reference numerals 101. Transmission shaft; 102. First gear; 103. Output shaft; 104. Second gear; 105. Gear 1; 106. Gear 2; 107. Housing; 108. Mounting cavity; 109. Third gear; 110. Fourth gear; 111. Power element; 113. Fifth gear; 115. Sixth gear; 116. Rotating shaft; 117. First fixing element; 118. Second fixing element; 119. Third fixing element; 121. First bearing; 122. Second bearing; 124. Input shaft; 125. Third bearing; 126. First shaft retaining ring; 127. First O-type bearing Seal; 128, first skeleton seal; 129, second O-ring seal; 130, third O-ring seal; 131, first bolt; 132, first hole retaining ring; 133, fourth bearing; 134, first spacer; 135, second hole retaining ring; 136, second shaft retaining ring; 137, second spacer; 138, third hole retaining ring; 139, first sleeve; 140, third shaft retaining ring; 141, composite sleeve; 142, first bearing seat; 143, fifth bearing; 144, fourth hole retaining ring; 145, second skeleton seal; 146, second bolt; 201. Arc surface of internal teeth; 202. Meshing surface of internal teeth; 203. Transition surface of internal teeth; 204. Cycloid surface of external teeth; 205. Transition surface of external teeth; 206. Top surface of external teeth. DETAILED DESCRIPTION

[0019] The following is a more detailed description of a reversible self-locking reduction drive device of the present invention, with reference to the accompanying drawings. Preferred embodiments of the present invention are shown, and it should be understood that those skilled in the art may modify the present invention described herein while still achieving the advantageous effects of the present invention. Therefore, the following description should be understood as being generally known to those skilled in the art and not as limiting the present invention.

[0020] In the description of this specification, "one embodiment" or "some embodiments" means that one or more embodiments of this specification include a particular feature, structure, or characteristic described in conjunction with the embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in other embodiments," etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized.

[0021] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0022] In the existing technology, photovoltaic tracking drive devices need to provide high reverse self-locking torque in strong wind environments, while meeting the requirements for long-term stable operation under low speed and heavy load conditions. Traditional reducers mostly use a worm gear structure reduction device, which has the problems of excessive axial size and low transmission efficiency, and it is difficult to balance the contradiction between high load-bearing capacity and compact structure. Similar cycloid reducers or small-tooth difference reducers have not been proven to have reliable reverse self-locking capabilities. The cycloid teeth and pinwheels used in the cycloid wheel use rolling friction and cannot form effective reverse self-locking. At the same time, the strength of the pin teeth and the tooth surface contact stress of the meshing surface are too large, affecting the requirements for load-bearing capacity. The involute tooth profile used in the small-tooth difference reducer affects the load-bearing capacity due to the limited number of meshing teeth when the internal and external teeth are meshing. At the same time, it is not suitable for application on photovoltaic tracking brackets due to the influence of tooth root fracture.

[0023] In order to solve the above problems, considering that the reducer requires a large static reverse self-locking holding torque in strong wind conditions and withstands alternating loads under intermittent motion conditions, it is considered to improve the load-bearing capacity by optimizing the gear meshing method. Based on the 2K-H differential principle, an attempt is made to combine the eccentric mounting structure with the circular arc tooth profile to explore the feasibility of an asymmetric meshing relationship. By analyzing the meshing characteristics of the external gear and the internal gear, it is found that the enveloping effect of the circular arc inner gear ring that fits the cycloid teeth on the eccentric cycloid outer teeth during reverse rotation and the two-stage gear reduction under relative sliding friction motion can form an effective reverse self-locking. Then, a bidirectional symmetrical arrangement scheme is conceived to balance the vibration load and meet the requirements for the bidirectional output of the reducer in the tracking bracket.

[0024] Therefore, the present invention proposes a reversible self-locking deceleration drive device, which is described below with reference to the attached drawings. Figure 1-8 A reversible self-locking reduction drive device according to an embodiment of the present invention is described.

[0025] According to the embodiment of the present invention, the reversible self-locking deceleration drive device, such as Figure 1-Figure 4As shown, it includes: a transmission shaft 101, a housing 107, a first gear 102 and two output shafts 103, and a third gear 109 integrally provided with the housing 107. The housing 107 is provided with a mounting cavity 108 that penetrates along a horizontal direction. The transmission shaft 101 is mounted in the mounting cavity 108 and extends along the penetration direction. The two output shafts 103 are symmetrically mounted at both ends of the transmission shaft 101, and the output shafts 103 are coaxial with the axis of the transmission shaft 101. The first gear 102 is eccentrically mounted on the transmission shaft 101, the first gear 102 is configured as an arc tooth external gear, including a gear 105 and a gear 2 106 with different numbers of teeth, a second gear 104 is formed on the output shaft 103 that meshes with the gear 1 105, the third gear 109 is eccentrically meshed with the gear 2 106, the second gear 104 and the third gear 109 are configured as arc tooth internal gears, and the eccentric directions of the two first gears 102 meshing with the two output shafts 103 are conjugated.

[0026] Among them, the transmission shaft 101 refers to a rotating shaft that transmits power, and can adopt a hollow shaft or solid shaft structure, which can be realized by forging alloy steel processing, and is used to support the gear set and transmit rotational motion. The eccentric installation of the output shaft 103 and the transmission shaft 101 means that there is a preset offset distance between the axes of the two, which can be realized by an eccentric shaft or an eccentric bearing to form an asymmetric meshing condition. Circular arc tooth gear refers to a gear pair whose tooth profile curve is a circular arc, and can be specifically modified by cycloid teeth or involute arcs to improve the load-bearing capacity by increasing the contact line length. The matching of the external gear and the internal gear refers to the meshing method of the outer ring gear and the annular inner ring gear, and can be specifically arranged with a double eccentric phase difference, and the self-locking effect is enhanced by the staggered distribution of the tooth surface contact area.

[0027] Specifically, the output shafts 103 at both ends of the transmission shaft 101 are eccentrically mounted to form symmetrically distributed power output points, and the eccentric mounting of the first gear 102 causes it to form a phase difference with the transmission shaft 101. When power is input, the meshing area of ​​the outer gear and the inner gear undergoes periodic changes under the action of eccentricity, forming a dynamic contact surface. Under the action of reverse load, the inner ring gear generates an envelope constraint on the outer gear, and the contact area of ​​the meshing tooth pair expands as the load increases. The eccentric direction conjugate setting, that is, the eccentric directions of the first gears 102 at the left and right ends meshing with the output shaft 103 are set in opposite directions, so that the meshing phases on both sides differ by 180 degrees, and the vibration loads on the transmission shaft 101 offset each other. The tooth surfaces of the inner and outer teeth of the arc tooth shape that contact each other are sliding friction during operation, which improves the stability of the reverse self-locking retention.

[0028] Compared to existing technologies, the reduction drive devices used in photovoltaic tracking systems often employ worm gear transmissions. While worm gears can achieve reverse self-locking, they are limited by their reduction ratio and size. When subjected to greater reverse torque, worm gears with involute teeth are prone to problems such as tooth root fracture. Reducers using worm gears lack reverse holding torque. Similar structures include cycloidal reducers and small-tooth-difference reducers, but neither type of reducer has been proven to effectively achieve reverse self-locking holding. The two-stage reduction structure employed in the present invention, combined with the design of circular arc teeth, enables the output shaft 103 to achieve reliable reverse holding torque. Compared to involute teeth, circular arc teeth can withstand greater loads without worrying about tooth root fracture. Optimization of circular arc teeth, such as tooth profile fitting, can further reduce tooth contact stress, improve holding torque, and mitigate impact loads. The left and right output shafts 103 are symmetrically arranged to accommodate the dual output of the tracking bracket. The first gear 102, which mates with the output shaft 103, is symmetrically arranged in the eccentric direction, eliminating eccentric loads on the transmission shaft 101.

[0029] Through the above technical solution, the present invention achieves the construction of a high-load-carrying transmission system within a confined space. The eccentric meshing of the external and internal gears creates a self-locking effect, and the unique shape of the circular-arc teeth allows the system to withstand transient impact loads exceeding 20 kN·m. Compared to a worm gear reducer of the same size, the reverse self-locking holding torque is nearly doubled. In photovoltaic tracking applications, this significantly improves the strength and reliability of the reduction gear in high wind conditions. Since photovoltaic tracking requires the output speed of the reducer to be only 0.01 to 0.02 revolutions per minute, the speed is extremely low. At the same time, the relative sliding rate of the tooth surface of the outer teeth is different in different meshing areas of the teeth. When the meshing surface 202 of the inner teeth is in a meshing state, the load borne by the tooth is large, but the relative sliding rate of the tooth surface is low. On the arc surface of the inner teeth, especially when close to the apex of the arc surface, the relative sliding rate is high, but the load borne is small. At the same time, through tooth shape optimization, the tooth top surface 206 of the outer teeth is in a disengaged state. Therefore, this feature ensures that the use of arc teeth can fully meet the wear of the photovoltaic tracking bracket at extremely low speeds. Combined with the material improvement of the present invention, it can fully meet the 25-year service life requirement of the photovoltaic tracking bracket.

[0030] In some embodiments of the present invention, Figure 3 、 Figure 4 The first gear 102 includes gear 1 105 and gear 2 106 . Gear 1 105 is engaged with the second gear 104 . Gear 2 106 is arranged away from the output shaft 103 and is integrally formed with gear 1 105 . The number of teeth of gear 1 105 is smaller than that of gear 2 106 .

[0031] Among them, the gear 105 refers to a transmission component that directly forms a meshing relationship with the second gear 104, and is specifically implemented by an arc tooth shape. Its number of teeth is designed to be smaller than that of the second gear 104, and the difference in the number of teeth is preferably 1 tooth difference. The cooperation between the gear 105 and the second gear 104 constitutes the second stage reduction at the output end. The first stage reduction is composed of the gear 2 106 and the third gear 109, which also adopts an arc tooth design. The number of teeth of the gear 2 106 is smaller than that of the third gear 109, and the difference in the number of teeth is preferably 1 tooth difference. Similarly, there is a difference in the number of teeth between the third gear 109 and the second gear 104, preferably 1 tooth difference or 2 tooth difference. Integral molding means that the gear 105 and the gear 2 106 are formed into an integral structure through forging and integral processing. Specifically, CNC processing can be used to ensure the coaxiality of the two gears and eliminate the axis offset error caused by the split assembly. The difference in the number of teeth means that the gear 105 and the gear 2 106 use different tooth ratios to form the transmission basis of multi-stage reduction.

[0032] Specifically, when Gear 1 105 meshes with Second Gear 104, the smaller tooth count difference improves the single-stage reduction ratio, while the placement of Gear 2 106 away from the output shaft 103 leaves room for the subsequent meshing of Third Gear 109. The one-piece structure creates a rigid connection between Gear 1 105 and Gear 2 106, preventing relative displacement of the separate gears under heavy loads while reducing the cumulative errors associated with assembly. The meshing transmission between Gear 2 106 and Third Gear 109 represents the first stage of reduction, while the meshing transmission between Gear 1 105 and Second Gear 104 represents the second stage of reduction. This two-stage reduction creates a higher reduction ratio and a reliable reverse self-locking retention structure.

[0033] Compared with the existing technology, such as worm gear reducers, the reduction ratio of worm gear reducers commonly used in photovoltaic tracking is around 50, while the reduction ratio of the patented invention can reach 300 or even higher through two-stage reduction, which is beneficial for situations requiring extremely low speeds in photovoltaic tracking. Compared with similar cycloid reducers, since cycloid reducers are single-stage reduction and have an external gear output, due to the eccentric rotation of the external gear, it is necessary to use a cantilever pin between the output shaft and the output external gear to eliminate the eccentricity, which greatly increases the number of parts and the risk of operational reliability. The patented invention uses two-stage reduction, in which the second gear 106 is eccentrically matched with the third gear 109, which serves as a fixed internal tooth, and the second gear 104, which is part of the output structure, is eccentrically matched with the first gear 105. Through the double eccentricity, the second gear 104, which serves as the output, is coaxial with the third gear 109, which serves as a fixed structure. This simplifies the output structure and increases operational stability. There is no cantilever pin design and the failure caused by the cantilever pin. The present invention uses an integrally formed double-gear structure to achieve a multi-stage deceleration effect due to the difference in the number of teeth while maintaining a compact layout.

[0034] Through the above-mentioned technical solution, the present invention achieves a superposition effect of high reduction ratios under conditions of limited axial space. The difference in the number of teeth between Gear 1 105 and Gear 2 106 forms an initial reduction stage, while reserving space for expansion in the subsequent transmission chain. The one-piece molded structure enables the gear assembly to maintain overall rigidity under heavy loads, avoiding fatigue fracture of the split structure under alternating loads. The layout of Gear 2 106 away from the output shaft 103 effectively isolates the risk of interference between different transmission stages, allowing for orderly transmission of multi-stage reduction within a compact space.

[0035] The housing 107 refers to a support structure surrounding the transmission system, which can be specifically realized by integral casting, and is used to support internal transmission components and maintain the rigidity of the overall structure. The mounting cavity 108 refers to a through-hole structure extending along the horizontal axis, which can be specifically formed into a cylindrical channel with a smooth inner wall through machining, ensuring that the transmission shaft 101 rotates in a directional manner along a fixed axis. The third gear 109 refers to an annular tooth structure fixed to the inner wall of the housing 107, which is integrally formed with the housing 107 and is made of ductile iron containing alloy elements through an austempering process to improve the material strength and hardness. The first stage of reduction is formed by eccentric meshing with the second gear 106.

[0036] Specifically, the housing 107 serves as an integral support frame, providing a radial positioning reference for the transmission shaft 101 through the mounting cavity 108, thereby eliminating radial offset caused by eccentric motion during transmission. The eccentric meshing relationship between the third gear 109 and the second gear 106 forms an alternating meshing state as the transmission shaft 101 rotates through a periodically changing tooth surface contact area, so that even small-angle output circumferential teeth can form uniform contact wear rather than local tooth wear, while dispersing load stress through multiple points of alternating contact. Under the action of reverse load, the meshing contact surface of the third gear 109 and the second gear 106 has an angular difference between the direction of the force and the direction of rotation due to the axial deviation of the two teeth, forming a self-locking angle, which prevents the transmission system from rotating in the opposite direction.

[0037] Compared to the prior art, traditional worm gear transmissions correspond to specific teeth on the worm wheel at specific angles. This causes uneven wear on the teeth due to the different loads borne at different rotation angles in photovoltaic tracking. However, with the structure of the present invention, all teeth engage even at very small output angles, resulting in more even wear. Furthermore, the internal gear third gear 109 and housing 107 are integrally formed, resulting in a more compact structure and avoiding the anchoring stability issues associated with a split design. By integrating the integral housing 107 with the eccentric meshing gears, the present invention achieves balanced dynamic load distribution while maintaining structural compactness.

[0038] Through the above-mentioned technical solution, the present invention solves the problem of insufficient transmission system stability under heavy-load conditions. The integrated design of the third gear 109 and the housing 107, as well as the integrated design of gear 105 and gear 2 106, reduces the anchoring connection of the main load-bearing components and improves the stability of the node connection. The eccentric meshing structure of the third gear 109 not only improves torque density, but also utilizes asymmetric contact characteristics to achieve a reverse self-locking function, meeting the photovoltaic tracking system's requirements for resisting sudden wind load impacts. The phase difference compensation mechanism of the gear pair effectively reduces transmission errors and ensures motion control accuracy under low-speed conditions.

[0039] It should be noted that different materials are used for the first gear 102, the second gear 104, and the third gear 109 to prevent internal and external teeth from gluing. For example, the external teeth are preferably made of bearing steel with a hardness of no less than HRC65 after quenching. The internal teeth are made of quenched ductile iron. Due to the greatly increased strength and hardness, the wear resistance of the bearing is greatly improved, while also avoiding the problem of tooth surface gluing caused by friction between the same materials. The use of ductile iron for the internal teeth also facilitates integral casting with the housing 107 and output shaft 103. After quenching, the surface hardness is further increased and the surface roughness is reduced through finishing processes such as shot peening and roller burnishing.

[0040] In some embodiments of the present invention, the circular arc tooth external gear (not marked in the figure) includes a cycloid surface 204 of the external tooth, a transition surface 205 of the external tooth, and a tooth top surface 206 of the external tooth. The cycloid surface 204 of the external tooth is determined by a curve generation equation. The tooth top surface 206 of the external tooth is set as a plane. The transition surface 205 of the external tooth connects the cycloid surface 204 of the external tooth and the tooth top surface 206 of the external tooth and smoothly connects the cycloid surface 204 of the external tooth and the tooth top surface 206 of the external tooth. The curve generation equation of the cycloid surface 204 of the external tooth is as follows: ; Where X is the X-axis coordinate on the curve; Y is the Y-axis coordinate on the curve; e is the eccentricity; α is the angle, ranging from 0 to 360 degrees; Z1 is the number of teeth of the internal gear meshing with the external gear; and R1 is the pitch radius of the internal gear.

[0041] The cycloid surface 204 of the external tooth refers to a tooth profile surface generated by a mathematical equation. Specifically, it can be defined using an equation that includes the eccentricity, the number of teeth on the internal gear, and the pitch radius, ensuring precise conjugate meshing of the tooth profile with the internal gear. The transition surface 205 of the external tooth refers to the geometric structure connecting the cycloid surface and the tooth top surface. Specifically, it can be implemented as a surface with continuously varying curvature to eliminate sudden changes in curvature at the tooth profile connection. The tooth top surface 206 of the external tooth refers to the planar area at the top of the gear tooth. Specifically, it can be implemented as a machined plane perpendicular to the gear axis to reduce stress concentration at the tooth top. The eccentricity e in the curve generation equation refers to the offset between the axes of the external and internal gears. This parameter can be adjusted to control the envelope of the tooth profile meshing trajectory. The angle α can range from 0 to 360 degrees to fully generate the cycloid tooth profile of a single tooth. The number of teeth Z1 and pitch radius R1 of the internal gear are incorporated into the equation to match internal gear pairs of different specifications.

[0042] Specifically, the tooth profile of the external arc tooth is generated: The tooth profile of the external arc tooth is generated by a curved surface generated by a curve equation and offset by an equal distance δ in the direction of the arrow.

[0043] The curve equation for the generated surface is as follows: ; X——X-axis coordinate on the curve; Y - the coordinate of the Y axis on the curve; e——eccentricity; α - angle, 0 to 360 degrees; Z1——the number of teeth of the internal gear meshing with the external gear; R1 - the pitch radius of the internal gear; Determination and optimization of eccentricity In this technical solution, the eccentricity coefficient K1 is preferably between 0.6 and 0.7, which can obtain a greater self-locking holding torque. The tooth profile shapes corresponding to different eccentricity coefficients are shown in the attached figure.

[0044] The distance δ from the curve generated by the curve equation to the tooth profile surface is determined and optimized. K2 is the tooth diameter coefficient of the internal gear. Due to the different material strengths of the internal and external gears, optimizing the tooth diameter coefficient can reduce contact stress at the meshing point and achieve equal strength design for the internal and external gears. The optimal value of the tooth diameter coefficient δ is between 1.65 and 1.8.

[0045] Generation of internal tooth profile: The internal tooth profile consists of three curved surfaces, namely the internal tooth arc surface 201, the internal tooth meshing surface 202, and the internal tooth transition surface 203. The internal tooth arc surface 201 is an arc circle, and the radius of the arc circle is The meshing surface 202 of the inner teeth has a radius of curvature close to that of the cycloidal surface of the outer teeth. When the swing angle Φ = arccos (K1), the bearing capacity of the meshing teeth is at its maximum. The meshing surface 202 of the inner teeth meshes with the cycloidal surface 204 of the outer teeth at this meshing angle, which can achieve a larger contact area and reduce surface contact stress. The transition surface 203 of the inner teeth is the transition surface from the meshing disengagement state to the meshing state. In order to facilitate machining, the curvature radius of the surface is usually not less than that of the circular arc surface 201 of the inner teeth.

[0046] Similarly, the tooth profile of the external circular arc tooth is also composed of three curved surfaces: the cycloid surface 204 of the external tooth, the transition surface 205 of the external tooth, and the tooth top surface 206 of the external tooth. The cycloid surface 204 of the external tooth is described above. This cycloid surface meshes with the circular arc surface 201 of the internal tooth and the meshing surface 202 of the internal tooth within a certain swing angle Φ range. The preferred swing angle of this meshing segment is generally within 100 degrees, ensuring that 5 to 6 teeth are engaged simultaneously. The transition surface 205 of the external tooth, composed of one or more circular arcs of a certain radius of curvature, serves as the transition section from the disengaged to the engaged state of the meshing teeth. The tooth top surface 206 of the external tooth is in a disengaged state from the internal circular arc tooth.

[0047] Furthermore, the angle between the pressure load direction and the movement direction of the tooth at the meshing position of each tooth is the meshing angle β. The meshing angles of different meshing tooth positions are different. The meshing angle applied to the tooth shape design of the present invention is usually not less than 45 degrees. At the same time, sliding friction is used between the internal and external teeth. When the two output shafts 103 are subjected to reverse torque, the component load of the reverse rotation of the outer arc teeth is smaller due to the large meshing angle between the teeth. At the same time, considering the resistance load caused by the large friction sliding, reliable self-locking will be achieved after the two-stage gear transmission.

[0048] In other words, the cycloid surface is generated through parameterized equations, so that the tooth profile of the external gear forms a precise conjugate relationship with the internal gear, thereby achieving simultaneous contact of multiple teeth during the meshing process. The transition surface connects the cycloid surface and the tooth top surface by continuously changing the curvature, avoiding local stress concentration caused by geometric mutations during the meshing process. The flat tooth top surface simplifies the processing technology and reduces the contact stress in the tooth top area. During the transmission process, the cycloid tooth profile of the external gear and the meshing surface of the internal gear are dynamically matched through equation parameters to ensure uniform load distribution under different meshing phases. By adjusting the eccentricity and the difference in the number of teeth, the area of ​​the tooth surface contact area can be optimized, thereby improving the load-bearing capacity of the gear pair.

[0049] Compared to existing technologies, small-tooth-difference reducers often use involute tooth profiles, where tooth contact is concentrated in the meshing areas of single or double teeth, leading to stress concentration and localized wear. Cycloidal surfaces, generated through mathematical equations, enable simultaneous engagement of multiple teeth, distributing loads across multiple tooth surfaces. The continuous curvature of the transition surface avoids the sudden stress spikes caused by the direct connection of cycloidal and straight segments in traditional tooth profiles. The flat tooth top surface reduces machining complexity and stress peaks at the tooth tip edge compared to traditional circular arc tooth top surfaces.

[0050] Through the above-mentioned technical solution, this application improves the load distribution characteristics during gear meshing, reduces the phenomenon of contact stress concentration on the tooth surface, and reduces tooth surface wear under extreme operating conditions. Through the precise cycloid tooth profile design, the transmission accuracy and stability are improved, and the service life of the gear pair under heavy-load intermittent motion conditions is extended. The smooth connection design of the transition surface effectively suppresses vibration and noise during meshing, enhancing the reliability of the reduction gear under shock load conditions.

[0051] In some embodiments of the present invention, the circular arc tooth internal gear (not marked in the figure) includes an arc surface 201 of the internal teeth, an engaging surface 202 of the internal teeth and a transition surface 203 of the internal teeth. The transition surface 203 of the internal teeth is a smooth transition surface connecting two adjacent engaging surfaces of the internal teeth. Only a part of the transition surface 203 of the internal teeth participates in the meshing with the external teeth. The meshing surface 202 of the internal teeth is formed by the motion fitting of the cycloid surface of the external teeth and smoothly transitions to the circular arc surface. In order to increase the meshing contact area, reduce local contact stress and improve the stability of reverse self-locking, the circular arc surface 201 of the internal teeth is composed of arc surfaces with equal curvature radius, ensuring multi-point contact with the external teeth, and the number of teeth engaging at the same time at any rotation angle is not less than 3 teeth. The circular arc tooth external gear and the circular arc tooth internal gear are in sliding friction.

[0052] The meshing curved surface 202 of the internal teeth refers to the meshing surface that matches the cycloid trajectory of the arc-toothed external gear. Specifically, this surface can be formed using a five-axis CNC machining center to maximize the contact area during meshing. The arc-shaped curved surface 201 of the internal teeth refers to the contact area for multi-point meshing. Specifically, a carburizing and quenching process can be used to increase the surface hardness to withstand contact stress under alternating loads. The transition curved surface 203 of the internal teeth refers to the smooth transition surface connecting two adjacent meshing curved surfaces of the internal teeth. Specifically, a variable radius arc transition design can be used to transition from contact to separation during meshing with the internal teeth. The requirement that the number of meshing teeth is not less than three is a mandatory constraint achieved through tooth profile parameter optimization. Specifically, tooth tip modification technology can be used to avoid contact between teeth at excessive pressure angles, thereby reducing contact stress and wear. Sliding friction refers to the movement that maintains surface contact between tooth surfaces. Specifically, high-viscosity grease can be used to increase surface contact stress to reduce wear rate and improve transmission smoothness.

[0053] Specifically, the meshing surface 202 of the internal teeth is generated through reverse engineering methods. Three-dimensional scanning and fitting are performed based on the cycloidal motion trajectory of the external teeth to form a conjugate meshing surface. This surface is divided into the main load-bearing area of ​​the tooth. By adopting a conjugate surface design, the contact area is increased and local contact stress concentration is reduced. Tooth surface damage caused by surface contact stress concentration is the main form of damage in arc-shaped teeth. This design can greatly increase the tooth's load-bearing capacity. The circular arc surface 201 of the internal teeth smoothly transitions with the meshing surface 202 of the internal teeth and is composed of circular arcs with equal curvature radii. This area can simultaneously contact the cycloidal surface 204 of the external teeth at different meshing phase angles, ensuring multi-point meshing. The sliding friction fit uses ductile iron containing self-lubricating materials and a high-viscosity lubricating grease containing molybdenum disulfide to form a boundary lubrication layer between the tooth surfaces, maintaining the necessary friction self-locking torque while avoiding excessive wear.

[0054] Compared with the existing technology, the few-tooth reducers mostly use involute teeth, which have low tooth strength, ensuring a small number of multi-teeth meshing at the same time, and insufficient load-bearing capacity. Traditional cycloid wheel designs mostly use single-pole reduction. Since the internal teeth are in the form of needle-tooth pins, the rolling friction between the pins and the cycloid wheel cannot form reverse self-locking. At the same time, the pins' own strength issues also make them unsuitable for applications in photovoltaic tracking that need to withstand large impact loads. This solution, through a multi-tooth synchronous meshing structure, distributes the load to more than three contact teeth, significantly improving the instantaneous overload capacity. As the load-bearing capacity increases, the number of meshing teeth will also increase. This solution uses a sliding friction surface contact design to increase the contact area under the same size, while using multi-tooth meshing to reduce wear and increase load-bearing capacity.

[0055] Through the above technical solution, this application can maintain the synchronous meshing state of at least three teeth when the photovoltaic tracking system is hit by strong winds, effectively dispersing peak torque loads and preventing overload damage to the tooth surfaces. The sliding friction-coordinated multi-tooth load-bearing structural design not only ensures reverse self-locking torque, but also extends the service life of the gear pair by optimizing the contact stress distribution. The continuous curvature variation of the transition surface ensures a smooth transition from disengaged to engaged teeth, allowing the gears to maintain stable operation under intermittent and frequent start-stop conditions.

[0056] In some embodiments of the present invention, the number of internal teeth of the second gear 104 is greater than the number of teeth of the gear 1 105, the number of internal teeth of the third gear 109 is greater than the number of teeth of the gear 2 106, and the difference in the number of teeth between the circular arc tooth internal gear and the circular arc tooth external gear is 1 tooth, and the difference in the number of teeth between the second gear 104 and the third gear 109 is 1 to 2 teeth.

[0057] The difference in tooth count of 1 between the arc-toothed internal gear and the arc-toothed external gear means that the internal gear has one more tooth than the external gear. This can be achieved by having 39 teeth on the external gear and 40 teeth on the internal gear. This design creates a multi-tooth meshing state through a small difference in tooth count. The difference in tooth count of 1 to 2 between the second gear 104 and the third gear 109 means that the difference in tooth count between the two gear pairs is distributed in a stepped manner. This can be achieved by having 40 teeth on the second gear 104 and 41 or 42 teeth on the third gear 109. This difference allows more internal and external teeth to contact simultaneously, increasing the bearing capacity of the teeth.

[0058] Specifically, when the difference in the number of teeth between the outer gear and the inner gear is 1 tooth, the inner gear produces a phase offset of one tooth for each rotation of the outer gear, forcing the meshing point to move continuously along the tooth surface, forming a multi-tooth simultaneous meshing effect. The difference in the number of teeth between the second gear 104 and the third gear 109 is controlled within the range of 1 to 2 teeth, so that the meshing phases of the two sets of gear pairs are staggered. During reverse transmission, since there is a certain angle between the force direction of the tooth surface and the contact direction of rotation, and since the inner and outer teeth, as described above, use conjugate surfaces to increase the contact area, the angle of some areas is within the friction angle range, thereby achieving a self-locking function. During intermittent motion, the stepped tooth number difference distribution allows different gear pairs to alternately bear the load, avoiding continuous impact on the same tooth surface area and reducing the local wear rate.

[0059] Through the above technical solution, this application solves the problem of insufficient reverse self-locking load maintenance of traditional reducers under extreme working conditions, and increases the self-locking torque to more than 10 times the rated output torque. Impact resistance is enhanced through multi-tooth meshing and phase dispersion, and the contact stress of the tooth surface is reduced when subjected to instantaneous impact. The stepped tooth number difference design causes the wear area of ​​the gear pair to shift periodically, extending the service life to twice that of the traditional design under the same working conditions, meeting the reliability requirements of 25 years of continuous operation of the photovoltaic tracking system. The transmission smoothness under intermittent motion conditions is improved through phase complementarity, and the vibration amplitude of the gear pair is reduced.

[0060] In some embodiments of the present invention, Figure 1 、 Figure 3-Figure 6 As shown, a fourth gear 110 is further included. The fourth gear 110 is installed in the housing 107 and fixedly installed on the transmission shaft 101 between the two first gears 102. The fourth gear 110 drives the transmission shaft 101 to rotate.

[0061] The fourth gear 110 is a transmission component with an external tooth structure, specifically an involute gear, whose tooth surface undergoes carburizing and quenching treatment to improve load-bearing capacity. This gear is rigidly fixed to the transmission shaft 101 via a keyway or flange connection, forming a direct power transmission path.

[0062] The fixed installation refers to a connection mode in which there is no relative rotation between the gear and the transmission shaft 101 , which can be specifically achieved by using the first fixing member 117 to ensure that no axial displacement occurs during the power transmission process.

[0063] Among them, the area between the two first gears 102 refers to the middle section of the transmission shaft 101 along the axial direction, which can be specifically set at an axially symmetrical position of 30% to 50% of the total length of the transmission shaft 101. The two first gears 102 are eccentric to the transmission shaft 101, and the first gears 102 on both sides are conjugately arranged 180 degrees eccentrically.

[0064] In some embodiments of the present invention, Figures 1-6 As shown, it also includes a power piece 111, which is installed on the housing 107. The housing 107 is provided with a through hole (not shown) connected to the installation cavity 108. The fifth gear 113 is fixedly installed on the output end of the power piece 111, and the fifth gear 113 passes through the through hole to transmit the torque to the fourth gear 110.

[0065] Among them, the power part 111 refers to a driving device for providing rotational power, which can be specifically implemented by a DC motor (preferred) or a stepping motor, and its output end is connected to the fifth gear 113 through the third fixing part 119 to achieve synchronous rotation. The through hole refers to a through-hole structure provided on the wall surface of the shell 107, which can be specifically implemented by casting preforming, and its maximum size is slightly larger than the outer diameter of the fifth gear 113 for easy assembly. The fifth gear 113 refers to a gear component that forms a meshing transmission with the fourth gear 110, and can be specifically implemented by a carburized and hardened steel spur gear or helical gear, and its tooth profile parameters form a matching meshing relationship with the fourth gear 110. The fourth gear 110 refers to a power input gear fixedly mounted on the transmission shaft 101, and its tooth surface is ground to improve transmission accuracy.

[0066] Specifically, the power member 111 is mounted on the outer surface of the housing 107 by means of bolt fastening, etc., to form a stable mounting base. Figure 5As shown, the power member 111 is fixed to the housing 107 by a second bolt 146. A communication channel is formed between the mounting cavity 108 inside the housing 107 and the external environment through the through hole, and the gear tooth portion of the fifth gear 113 extends through the channel into the mounting cavity 108. The power member 111 and the fifth gear 113 are mated in a keyway manner to achieve synchronous rotation, and the rotational torque is transmitted to the transmission shaft 101 through the meshing contact surface between the fifth gear 113 and the fourth gear 110. The lubricating grease in the mounting cavity 108 is isolated by providing a seal between the through hole and the shaft neck of the fifth gear 113 to prevent external contaminants from entering the transmission system.

[0067] In some embodiments of the present invention, Figure 1 、 Figure 3-Figure 6 As shown, a sixth gear 115 is further included. The sixth gear 115 is installed in the installation cavity 108 and the sixth gear 115 is meshed with the fourth gear 110 and the fifth gear 113 respectively.

[0068] The sixth gear 115 may be installed in the installation cavity 108 by using a bracket (not shown). The bracket refers to a supporting structure for fixing the sixth gear 115 . The bracket may also be integrally formed with the housing.

[0069] The sixth gear 115 is an intermediate transmission gear, which is a straight-tooth or helical-tooth gear and is a transition gear for torque transmission by simultaneously meshing with the fourth gear 110 and the fifth gear 113 .

[0070] Specifically, the bracket is mounted on the inner wall of the housing, forming a stable support base. After the sixth gear 115 is mounted on the bracket, its tooth surfaces mesh with the fourth gear 110 and the fifth gear 113, respectively. When the power member 111 drives the fifth gear 113 to rotate, torque is transmitted to the fourth gear 110 through the sixth gear 115, thereby driving the transmission shaft 101 to rotate. During this process, the sixth gear 115 serves as a transition node in the torque transmission path.

[0071] In some embodiments of the present invention, Figure 5 、 Figure 6 As shown, it further includes a rotating shaft 116 , which is installed in the installation cavity 108 , and the sixth gear 115 is rotatably installed on the rotating shaft 116 .

[0072] Among them, the rotating shaft 116 refers to a rigid shaft body used to carry the rotational movement of the sixth gear 115, which can be specifically realized by a stepped shaft or an optical shaft combined with a keyway structure. Its two ends are fixed in the mounting hole of the bracket by interference fit or threaded connection, providing stable radial positioning for the sixth gear 115.

[0073] Among them, the sixth gear 115 is rotatably mounted on the rotating shaft 116, which means that the inner hole of the gear and the outer surface of the rotating shaft 116 form a clearance fit or a rolling bearing connection, which can be specifically achieved by using a deep groove ball bearing or a sliding bearing, so that the sixth gear 115 can rotate freely around the axis of the rotating shaft 116 while limiting axial displacement.

[0074] Specifically, the bracket serves as the supporting structure of the transmission system, and its rigidity directly affects the gear meshing accuracy. The rotating shaft 116 is fixed to a predetermined position of the bracket by a mechanical connection, forming a stable rotation line reference for the rotating shaft 116. The sixth gear 115 is assembled on the rotating shaft 116 through a bearing assembly. When the torque between the fourth gear 110 and the fifth gear 113 is transmitted, the rotating shaft 116 bears the radial load generated by the gear meshing. When there is an assembly error or load fluctuation in the transmission system, the sixth gear 115 can perform micro-self-adjustment around the rotating shaft 116 to eliminate the uneven distribution of contact stress on the tooth surface.

[0075] In some embodiments of the present invention, further comprising: The first fixing member 117, such as Figure 6 As shown, the first fixing member 117 is installed between the third gear 109 and the transmission shaft 101 to fix the fourth gear 110 on the transmission shaft 101; The second fixing member 118, such as Figure 2 As shown, the second fixing member 118 is installed between the transmission shaft 101 and the first bearing 121 to fix the first bearing 121 on the transmission shaft 101; The third fixing member 119, such as Figure 5 As shown, the third fixing member 119 is installed between the output end of the power member 111 and the fifth gear 113 to fix the fifth gear 113 on the output end of the power member 111 .

[0076] The first fixing member 117 is a torque transmission structure for connecting the transmission shaft 101 and the fourth gear 110. Specifically, this can be achieved using a combination of a keyway and a flat key. The flat key transmits the torque of the fourth gear 110 to the transmission shaft 101. The second fixing member 118 is used to transmit torque between the inner ring of the first bearing 121 and the transmission shaft 101. The first bearing 121 is designed as an eccentric bearing, and is axially positioned on the transmission shaft 101 using a spacer sleeve and a retaining spring. The third fixing member 119 is used to transmit torque between the input shaft 124 and the fifth gear 113. It is used to transmit the power torque of the power member 111 to the fifth gear 113, driving the gears to rotate.

[0077] Specifically, a keyway is machined on the mating surface between the transmission shaft 101 and the fourth gear 110 and a flat key is installed. A stepped shoulder is machined on the transmission shaft 101 at the installation position of the first bearing 121, and a retaining ring groove is opened on the other side of the shoulder to install an elastic retaining ring, so that the inner ring of the bearing is precisely limited within the axial range.

[0078] It should be noted that the first fixing member 117, the second fixing member 118 and the third fixing member 119 can also adopt any other structural members that can achieve the above-mentioned fixing function, such as flat keys, positioning pins, etc., which are not described in detail here.

[0079] In some embodiments of the present invention, the reduction ratio between the output end of the power member 111 and the output shaft 103 can be set arbitrarily, wherein the reduction ratio is preferably greater than 100, and different gear differences and tooth number ratios can form a larger reduction ratio range.

[0080] The reduction ratio refers to the ratio of the output speed of the power element 111 to the speed of the output shaft 103. This is achieved using a multi-stage gear transmission structure, specifically a two-stage, small-tooth-difference planetary gear reduction mechanism. This parameter range allows for the conversion of high-speed rotation of the power source into ultra-low-speed motion at the output, while also meeting heavy-duty requirements through torque amplification.

[0081] Specifically, when the high-speed rotation output by the power element 111 is transmitted to the output shaft 103 via a multi-stage reduction mechanism, the reduction ratio reaches or exceeds 100, thereby controlling the speed of the output shaft 103 within the range of 0.01-0.03 revolutions per minute. During this process, the low torque at the input end is gradually amplified through gear meshing, ultimately generating the peak torque required by the photovoltaic tracking bracket at the output end. Because the reduction ratio is directly related to the gear tooth ratio, the use of a multi-stage reduction structure can achieve a high reduction ratio within a limited space. At the same time, the mechanical self-locking effect generated by the gear meshing prevents the output shaft 103 from rotating in the opposite direction.

[0082] The present invention combines a specific reduction ratio range with a multi-stage transmission structure to achieve speed control and torque amplification at the same time without the need for an additional braking mechanism, and uses the transmission system's own friction to achieve reverse self-locking. The use of arc teeth increases the reverse self-locking holding capability.

[0083] Through the above technical solution, the present invention realizes the requirement of the photovoltaic tracking drive device for extremely low output speed by realizing a large reduction ratio in a compact structure. At the same time, reliable reverse self-locking holding torque is realized through the design of arc teeth and the two-stage reduction structure under limited size specifications. The application of arc teeth ensures multi-point engagement during operation and in a stationary state, avoids the risk of tooth root fracture, and meets the strength requirements of the drive device of the photovoltaic tracking bracket under strong winds.

[0084] In some embodiments of the present invention, Figure 2 As shown, it also includes: a first bearing 121 , wherein the first bearing 121 is mounted on the transmission shaft 101 , and the first gear 102 is mounted on the transmission shaft 101 via the first bearing 121 ; a second bearing 122 , which is mounted on the output shaft 103 and disposed near the end of the transmission shaft 101 . The inner ring of the second bearing 122 cooperates with the transmission shaft 101 to prevent interference between the transmission shaft 101 and the output shaft 103 ; A composite sleeve 141 is installed in the housing. The inner ring of the composite sleeve 141 cooperates with the outer ring of the output shaft 103 to radially support the output shaft 103 .

[0085] The first bearing 121 is a rolling support component installed between the transmission shaft 101 and the first gear. Specifically, it can be implemented by a deep groove ball bearing or a cylindrical roller bearing. Its function is to provide low-friction support for the eccentric rotation of the first gear. The second bearing 122 is a positioning component arranged at the junction of the output shaft 103 and the transmission shaft 101. Specifically, it can be implemented by an angular contact ball bearing or a tapered roller bearing. Its inner ring has an interference fit with the transmission shaft 101 to constrain the radial displacement of the output shaft 103. The composite sleeve 141 is a radial support member made of a self-lubricating material. Specifically, it can be implemented by a composite structure of a PTFE-based composite material and a metal matrix. Its inner ring forms a sliding support interface with a clearance fit on the outer surface of the output shaft 103.

[0086] Specifically, the rolling elements of the first bearing 121 form rolling contact between the transmission shaft 101 and the first gear, converting the sliding friction generated by the eccentric motion of the gear into rolling friction. The inner ring of the second bearing 122 forms a rigid connection with the transmission shaft 101, establishing an axial positioning reference at the end of the output shaft 103, and eliminating the relative radial offset between the transmission shaft 101 and the output shaft 103. The inner ring surface of the composite sleeve 141 maintains a constant gap with the outer circle of the output shaft 103, absorbing the radial load fluctuations of the output shaft 103 during eccentric motion through elastic deformation, while maintaining the stability of the support interface by utilizing the low friction characteristics of the self-lubricating material. The support system composed of the three forms multi-point constraints in the transmission shaft 101 system, and balances the periodic loads generated by eccentric motion through the synergistic effect of rolling support and sliding support.

[0087] Compared to existing technologies, traditional reduction gears typically use a single deep-groove ball bearing to support the transmission shaft 101. This can lead to increased bearing clearance and support failure under eccentric loads. Existing bushing structures often use a single metal bushing, which lacks elastic compensation and has a high coefficient of friction. This solution, through the combined design of a rolling bearing and the composite bushing 141, achieves flexible load transfer while maintaining transmission accuracy, effectively suppressing shaft deformation.

[0088] Through the above technical solution, the present application maintains the coaxiality of the transmission shaft 101 and the output shaft 103 under heavy-load impact conditions, reduces the friction loss caused by the eccentric movement of the gears, and compensates for the radial displacement of the output shaft 103 through the elastic support of the composite sleeve 141, thereby solving the problem of abnormal gear meshing caused by insufficient support stiffness during the reverse self-locking process of the traditional structure, and significantly improving the operating reliability of the reduction device under intermittent impact loads.

[0089] It should be noted that the first bearing 121 and the second bearing 122 can adopt eccentric bearings to realize the eccentric design of the first gear 102 and the output shaft 103. The first bearing 121 and the second bearing 122 can also adopt non-eccentric bearings and set the transmission shaft 101 as an eccentric structure to realize the eccentric design of the first gear 102 and the output shaft 103. Furthermore, the eccentric setting of the first gear 102 and the output shaft 103 can also be realized by the combination of the first bearing 121, the second bearing 122 and the transmission shaft 101, which will not be repeated here.

[0090] In summary, an embodiment of the reversible self-locking deceleration drive device is as follows: Figures 1-8 As shown: The power member 111 provides driving torque, and the fifth gear 113 drives the fourth gear 110 to rotate through the sixth gear 115 , wherein the fourth gear 110 transmits the torque to the transmission shaft 101 through the first fixing member 117 .

[0091] The power member 111 transmits torque to the input shaft 124 via the third fixing member 119. The input shaft 124 is radially supported by a third bearing 125. One third bearing 125 is fixed in the mounting cavity 108, and another third bearing 125 is fixed in the first bearing seat 142. The input shaft 124 is connected to the fifth gear 113 via the third fixing member 119, transmitting torque and driving the fifth gear 113 to rotate. The first shaft retaining ring 126 is used to prevent axial movement, and the first O-ring seal 127 and the first skeleton seal 128 realize dynamic torsional sealing of the input shaft 124. The second O-ring seal 129 realizes static sealing of the first bearing seat 142, and the third O-ring seal 130 seals the power member 111.

[0092] The fifth gear 113 is externally meshed with the sixth gear 115. The sixth gear 115 rotates in the opposite direction to the fifth gear 113 and is mounted on the rotating shaft 116 via a fourth bearing 133. The rotating shaft 116 is fixed within the mounting cavity 108 and secured by a first bolt 131. A retaining ring 132 is used in the first hole to axially secure the fourth bearing 133. A first spacer 134 prevents axial movement of the sixth gear 115.

[0093] The sixth gear 115 meshes externally with the fourth gear 110, transmitting torque from the fifth gear 113 and ultimately transferring the torque to the transmission shaft 101 via the first fixing member 117, thereby driving the circular arc gear. A fifth bearing 143 is secured within the mounting cavity 108, providing radial support for the transmission shaft 101. A second hole retaining ring 135 provides axial fixation. A second shaft retaining ring 136 and a second spacer 137 axially secure the fourth gear 110, preventing axial movement.

[0094] The two output shafts 103 are symmetrical in structure. A second gear 104 is installed within each output shaft 103, meshing with gear 1 105 of the first gear 102. Driven by the first bearing 121, the first gear 102 oscillates eccentrically relative to the centerline of the transmission shaft 101. Gear 2 106, located on the other side of the first gear 102, meshes with the third gear 109 located within the mounting cavity 108, forming a two-stage gear reduction output. The inner ring of the first bearing 121 is connected to the transmission shaft 101 via the second fixing member 118, allowing it to rotate eccentrically around its axis. The first bearing 121 is mounted within the cavity of the first gear 102 and axially secured by a third hole retaining ring 138. A first bushing 139 and a third shaft retaining ring 140 secure the first gear 102 axially. A composite bushing 141 provides radial support for the output shaft 103 and is installed within the mounting cavity 108. The composite sleeve 141 is preferably made of a self-lubricating composite material. A fifth bearing 143 is mounted within the internal cavity of the output shaft 103 and provides radial support for the transmission shaft 101. A fourth retaining ring 144 is used to limit axial movement of the output shaft 103, and a second frame seal 145 provides a dynamic rotary seal for the output shaft 103.

[0095] It should be noted that in the present invention, during the meshing of circular arc gears, multiple pairs of teeth simultaneously engage at any meshing angle, and the pressure angle varies as the meshing angle changes. By controlling the pressure angle of the meshing teeth through measures such as tooth profile modification and combining this with the two-stage reduction transmission structure described in this technical solution, self-locking retention of the output teeth at any angle can be achieved.

[0096] It should be understood that the above-described specific embodiments of the present invention are merely illustrative or illustrative of the principles of the present invention and do not constitute limitations of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included within the scope of protection of the present invention. In addition, the appended claims are intended to cover all variations and modifications that fall within the scope and metes and bounds of the appended claims, or equivalents thereof.

Claims

1. A reversible self-locking deceleration drive device, characterized in that: include: A transmission shaft, a housing, a first gear and two output shafts, and a third gear integrally arranged with the housing, the housing is provided with a mounting cavity extending along a horizontal direction, the transmission shaft is installed in the mounting cavity and extends along the penetration direction, the two output shafts are symmetrically installed at both ends of the transmission shaft, and the output shaft is coaxial with the axis of the transmission shaft, the first gear is eccentrically installed on the transmission shaft, the first gear is configured as an arc tooth external gear, including gear one and gear two with different numbers of teeth, a second gear is formed on the output shaft that meshes with gear one, the third gear is eccentrically meshed with gear two, the second gear and the third gear are configured as arc tooth internal gears, and the eccentric directions of the two first gears meshing with the two output shafts are conjugated.

2. The reversible self-locking speed reduction drive device according to claim 1, characterized in that: The arc tooth external gear includes a cycloid surface of the external tooth, a transition surface of the external tooth, and a tooth top surface of the external tooth. The cycloid surface of the external tooth is determined by a curve generation equation. The tooth top surface of the external tooth is set as a plane. The transition surface of the external tooth connects the cycloid surface of the external tooth and the tooth top surface of the external tooth and smoothly connects the cycloid surface of the external tooth and the tooth top surface of the external tooth. The curve generation equation of the cycloid surface of the external tooth is as follows: ； Wherein, X is the X-axis coordinate on the curve; Y is the Y-axis coordinate on the curve; e is the eccentricity; α is the angle, ranging from 0 to 360 degrees; Z1 is the number of teeth of the internal gear meshing with the external gear; and R1 is the pitch radius of the internal gear.

3. The reversible self-locking speed reduction drive device according to claim 2, characterized in that: The circular arc tooth internal gear includes an arc surface of the internal teeth, an engaging surface of the internal teeth and a transition surface of the internal teeth. The transition surface of the internal teeth is a smooth transition surface connecting the engaging surfaces of two adjacent internal teeth. Only a part of the transition surface of the internal teeth participates in the meshing with the external teeth. The meshing surface of the internal teeth is formed by the cycloid surface motion fitting of the external teeth and smoothly transitions to the circular arc surface of the internal teeth. The circular arc surface of the internal teeth is composed of arc surfaces with equal curvature radius, and the number of teeth engaging at the same time at any rotation angle is not less than 3 teeth. The circular arc tooth external gear and the circular arc tooth internal gear are in sliding friction.

4. The reversible self-locking speed reduction drive device according to claim 1, characterized in that: The number of internal teeth of the second gear is greater than the number of teeth of the gear one, the number of internal teeth of the third gear is greater than the number of teeth of the gear two, and the difference in the number of teeth between the circular arc tooth internal gear and the circular arc tooth external gear is 1 tooth, and the difference in the number of teeth between the second gear and the third gear is 1 to 2 teeth.

5. The reversible self-locking speed reduction drive device according to claim 1, characterized in that: It also includes a fourth gear, which is installed in the housing and fixedly installed on the transmission shaft between the two first gears. The fourth gear drives the transmission shaft to rotate.

6. The reversible self-locking speed reduction drive device according to claim 5, characterized in that: It also includes a power piece, which is installed on the shell. The shell is provided with a through hole connected to the installation cavity. A fifth gear is fixedly installed on the output end of the power piece. The fifth gear passes through the through hole to transmit torque to the fourth gear.

7. The reversible self-locking speed reduction drive device according to claim 6, characterized in that: It also includes a bracket and a sixth gear, wherein the bracket is mounted on the inner wall of the shell and is located between the two first gears, and the sixth gear is mounted on the bracket and is respectively engaged with the fourth gear and the fifth gear.

8. The reversible self-locking speed reduction drive device according to claim 7, characterized in that: It also includes a rotating shaft, which is installed on the bracket, and the sixth gear is rotatably installed on the rotating shaft.

9. The reversible self-locking speed reduction drive device according to claim 8, characterized in that: Also includes: a first bearing, wherein the first bearing is mounted on the transmission shaft, and the first gear is mounted on the transmission shaft via the first bearing; a second bearing, the second bearing being mounted on the output shaft and disposed near an end of the transmission shaft, wherein an inner ring of the second bearing cooperates with the transmission shaft to provide radial support for the transmission shaft; A composite sleeve is installed in the housing, and the inner ring of the composite sleeve cooperates with the outer ring of the output shaft to radially support the output shaft.

10. The reversible self-locking speed reduction drive device according to claim 9, characterized in that: Also includes: a first fixing member, the first fixing member being installed between the fourth gear and the transmission shaft to fix the fourth gear on the transmission shaft; a second fixing member, the second fixing member being installed between the transmission shaft and the first bearing, and fixing the inner ring of the first bearing on the transmission shaft; A third fixing member is installed between the output end of the power member and the fifth gear, and fixes the fifth gear on the output end of the power member.

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