Stamping retainer of 3K planetary gear mechanism

Abstract

The stamping retainer of the 3K planetary gear mechanism is composed of a first stamping piece and a second stamping piece, the first stamping piece is composed of a flat plate portion and a plurality of connecting pieces evenly distributed in the circumferential direction, and the first stamping piece is in a petal shape; each connecting sheet is connected with a corresponding mortise in the second stamping sheet, or welding is carried out while all the mortises are connected; central holes are formed in the center of the flat plate part of the first stamping sheet and the center of the second stamping sheet; planetary gear shaft holes which are evenly distributed in the circumferential direction and are equal to the connecting pieces in number are formed outside respective central holes of the flat plate part of the first stamping piece and the second stamping piece. Central holes of the first stamping sheet and the second stamping sheet are provided with outer convex parts, and planetary gear shaft holes of the first stamping sheet and the second stamping sheet are provided with inner convex supporting parts; the connecting sheet is provided with a rib-shaped stamping groove; the connecting piece is provided with a step-shaped structure, and the lower size is larger than the upper size. The transmission device is compact in transmission, simple in structure, low in manufacturing cost, high in space utilization rate and capable of effectively absorbing load fluctuation and improving uniform load performance.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of planetary gear transmission system, concretely relates to a 3K planetary gear mechanism stamping retainer. BACKGROUND

[0002] 3K type planetary transmission is a very compact transmission form in epicyclic gear train, and its name is derived from the fact that three central wheels (K) are contained in the system, and the three central wheels can be sun gears or inner rings. The planetary gears in the system generally adopt double gear structure, which are engaged with different central wheels, thereby building multiple transmission paths and achieving super large transmission ratio. Due to its unique advantages, 3K type planetary transmission is widely used in various wheel edge reducers, robot joint reducers and aerospace and many other fields with high requirements for transmission performance.

[0003] In the 3K type planetary transmission system, the planet carrier plays a crucial role. It not only bears the task of connecting and supporting the planetary gears, but also ensures uniform load distribution, which is of great significance to improving transmission accuracy and prolonging system service life. Currently, the planet carrier mainly has the following structural forms: double-sided plate integral type, double-sided plate separated type and single-sided plate type.

[0004] The traditional planet carrier design has the following problems: first, the manufacturing process is complex, resulting in high production cost, especially in the application scenarios of compact reducers such as robot joints, it is difficult to meet the actual demand; second, in the application of compact reducers, the existing design is difficult to meet the space limitation requirement; third, the traditional planet carrier structure has large rigidity, which is difficult to effectively absorb load fluctuation, which may cause high tooth surface contact stress; finally, the traditional design is difficult to compensate for the errors generated in the manufacturing process, affecting the load sharing performance of the system. SUMMARY

[0005] The utility model aims at the shortage of prior art, provides a kind of 3K planetary gear mechanism stamping retainer, not only can realize compact transmission, also has the advantages such as simple structure, low manufacturing cost, high space utilization, can effectively absorb load fluctuation, improve load sharing performance.

[0006] The technical scheme adopted by the utility model is as follows:

[0007] The utility model discloses a first stamping sheet and second stamping sheet, the first stamping sheet is composed of flat plate part and the multiple connecting sheet that is evenly distributed along the circumference, the connecting sheet is bent to be 90 with flat plate part, and the first stamping sheet is petal-shaped as a whole, the connecting sheet is equipped with tenon, and the second stamping sheet is equipped with the mortise hole equal to the number of connecting sheet, and each tenon is connected with the corresponding mortise hole, or each tenon is connected with the corresponding mortise hole and is welded simultaneously.

[0008] Further, the number of connecting sheet and planetary gear shaft hole is equal, one planetary gear shaft hole is arranged between each two adjacent connecting sheets, and one planetary gear shaft hole is arranged between each two adjacent mortise holes.

[0009] Further, the central hole of the first stamping sheet and second stamping sheet is equipped with the outer convex part, and each planetary gear shaft hole of the first stamping sheet and second stamping sheet is equipped with the inner convex supporting part.

[0010] Further, the connecting sheet is equipped with the rib-shaped stamping groove.

[0011] Further, the connecting sheet is equipped with the stepped structure, and the size of lower part is greater than the size of upper part.

[0012] Further, the number of connecting sheet and planetary gear shaft hole is limited to 3-5.

[0013] The utility model has the following beneficial effects:

[0014] Considering the characteristics of 3K planetary gear mechanism retainer, that is, it supports planetary gear shaft and enables it to revolve, but does not directly transmit torque, and only exists as a kinematic constraint component. Based on this characteristic, the utility model discloses a stamping part design, including petal-shaped first stamping sheet and second stamping sheet, which are fixed by mortise joint or mortise joint and laser welding at the same time, and are used for maintaining the upper surface, lower surface and center distance of multiple double planetary gears. This design adopts stamping part structure, simplifies the manufacturing process, and reduces the production cost. At the same time, the elastic property of the stamping part can effectively absorb load fluctuation and reduce tooth surface contact stress. In addition, the slight floating of the stamping retainer can compensate for manufacturing errors and improve load sharing performance. Therefore, the technical scheme of the utility model not only realizes compact transmission, but also has the advantages of simple structure, low manufacturing cost, high space utilization, effective load fluctuation absorption, and improved load sharing performance. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 An explosion diagram of the 3K planetary gear mechanism stamping retainer is provided.

[0016] Figure 2 The utility model provides a kind of 3K planetary gear mechanism stamping retainer's assembly perspective view.

[0017] Figure 3 The utility model provides a kind of 3K planetary gear mechanism stamping retainer's sectional view.

[0018] Figure 4 It is the schematic view before the first stamping piece in the utility model is bent in connecting piece.

[0019] Figure 5 The utility model provides a kind of 3K planetary gear mechanism stamping retainer on assembly three double planetary gears schematic view.

[0020] In the drawing: 1, first stamping piece;2, second stamping piece;3, connecting piece;4, mortise hole;5, planetary gear shaft hole;6, central hole;7, muscle stamping groove;8, weld. DETAILED DESCRIPTION

[0021] The technical scheme in the embodiments of the utility model will be described clearly and completely below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only a part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0022] 3K planetary transmission system is widely used in the field of wheel edge reducer, robot joint reducer as a compact and efficient transmission form. The holding problem of planetary gear becomes the key factor affecting system performance.

[0023] Take robot joint reducer as an example, its working environment requires that transmission system has high precision, high stiffness and high reliability. In this application scenario, the holding problem of planetary gear is particularly prominent. Specifically, first, the traditional double-sided plate integral or separated type planetary carrier structure is complex, and it is difficult to realize compact design in limited space;Second, the upper and lower surfaces of planetary gear and center distance are difficult to control accurately, which leads to the decline of gear meshing precision;Third, the planetary carrier structure with high rigidity is difficult to absorb load fluctuation, which increases the tooth surface contact stress.

[0024] When solving the technical problem of holding planetary gear in 3K planetary gear mechanism, the utility model first considers the influence of position accuracy and motion stability of planetary gear on transmission system efficiency and service life, and starts to explore a new scheme to simplify manufacturing process while effectively holding planetary gear position.

[0025] The utility model provides a thought of using stamping process to make the retainer. Stamping process has the advantages of high production efficiency and low cost, and can well solve the problem of complex manufacturing process. However, how to ensure that the stamped part can effectively maintain the position of the planetary gear becomes the next problem to be solved. The utility model provides the idea of using petal-shaped design. The petal-shaped design can provide better support and retention effect while ensuring compact structure. Specifically, the petal-shaped structure can better fit the shape of the planetary gear, thereby more accurately controlling the position of the gear.

[0026] Further, the utility model considers how to realize the retention of the upper and lower surfaces of the planetary gear. The traditional single-sided plate type planet carrier is difficult to control the upper and lower surfaces of the gear at the same time, so the utility model provides a scheme of using two stamped parts. Through the cooperation of the upper and lower two stamped parts, the upper and lower surface positions of the planetary gear can be effectively controlled.

[0027] However, how to connect the upper and lower two stamped parts becomes a new problem. Considering that the connection method needs to ensure structural strength and facilitate assembly, the utility model provides a scheme of using mortise riveting or laser welding. These two connection methods can provide sufficient connection strength while maintaining the compactness of the structure. In order to further improve the reliability of the connection, the utility model also considers a scheme of simultaneously using the two connection methods.

[0028] Finally, the utility model focuses on how to utilize the characteristics of the stamped part to improve system performance. The elastic deformation characteristics of the stamped part can be used to absorb load fluctuations and reduce tooth surface contact stress. This characteristic can improve the running stability and service life of the system, which is an important advantage compared with the traditional rigid planet carrier.

[0029] Thus, embodiment 1 is formed:

[0030] The utility model provides a kind of 3K planetary gear mechanism stamping retainer, as shown in Figure 1 、 2 And 3, including first stamping sheet 1 and second stamping sheet 2, first stamping sheet and second stamping sheet are formed by stamping process, specifically can be realized by using sheet metal stamping forming. First stamping sheet 1 is composed of flat plate part and the multiple connecting pieces 3 that are evenly distributed along the circumference, and the connecting piece 3 is bent to be 90 ° with the flat plate part, and the first stamping sheet 1 is in the shape of petal as a whole, this structural design can better fit the shape of planetary gear, while having more accurate position accuracy. Connecting piece 3 is shown as Figure 4 before bending, and after bending, as Figure 1The connecting piece 3 is provided with tenons, and the second stamping piece is provided with tenon holes 4 equal in number to the connecting piece 3, each tenon being connected with a corresponding tenon hole 4 or each tenon being connected with a corresponding tenon hole 4 while being welded. The flat plate part of the first stamping piece and the center of the second stamping piece are each provided with a central hole 6 penetrating the flat plate part or the second stamping piece; the central hole 6 provides installation space for the central shaft of the double planetary gear, facilitating assembly. The flat plate part of the first stamping piece and the second stamping piece are each provided with n planetary gear shaft holes 5 uniformly distributed in the circumferential direction outside the respective central holes 6, n≥3; the planetary gear shaft holes 5 support the double planetary gear. The utility model is used for maintaining the upper surface, lower surface and center distance of multiple double planetary gears, the first stamping piece 1 is in the shape of a petal in the whole, and the axial position and radial position of the planetary gear can be accurately controlled through the cooperation of the first stamping piece and the second stamping piece and the position of the planetary gear shaft hole 5 on the first stamping piece and the second stamping piece, so as to control the center distance. This layout ensures the correct positioning and stable operation of the double planetary gear, which helps to improve the operation accuracy and efficiency of the whole system. Among them, the double planetary gear refers to a planetary gear structure in which two gears are fixed together, which can be realized by axially fixed connection of two gears with different diameters, as Figure 5 shown.

[0031] Both the tenon connection and the tenon connection while welding of the connecting piece 3 and the second stamping piece 2 can provide sufficient connection strength while maintaining the compactness of the structure. Specifically, tenon connection is suitable for occasions that need to be disassembled or replaced, while tenon connection while welding provides higher connection strength. This design scheme also has the following advantages: first, it simplifies the structure of the retainer, improves the overall rigidity of the retainer, can realize firm connection, ensures assembly accuracy, improves the overall strength and stability, reduces the deformation and vibration of the connecting piece 3 during high-speed operation, and is beneficial to improve the operation reliability and service life of the planetary gear mechanism; second, through the design of the connecting piece, the stress distribution can be optimized, and the risk of local stress concentration can be reduced; finally, this structure is convenient for mass production, which is beneficial to reduce the manufacturing cost.

[0032] As a preferred, the welding can adopt laser welding, which uses a high-energy laser beam to weld on the contact surface of the two stamping pieces, and the weld 8 is as shown in Figure 2 and 3 .

[0033] As a preferred, the first stamping piece and the second stamping piece can adopt different materials and thicknesses to adapt to different application requirements. For example, steel or lightweight alloy materials can be selected. The design of the connecting piece can adopt different shapes, such as T-shaped, L-shaped or straight-shaped, and reinforcing ribs can also be added to improve the strength.

[0034] As preferred, the number of connecting pieces and planet gear shaft holes 5 is equal, one planet gear shaft hole 5 is arranged between every two adjacent connecting pieces, and one planet gear shaft hole 5 is arranged between every two adjacent tenon holes 4. This design scheme can evenly distribute the support force in the circumferential direction by ensuring that each double planet gear has a corresponding connecting piece support, thereby reducing local stress concentration, improving the running stability of the retainer while ensuring the structural strength, achieving higher transmission efficiency and longer service life.

[0035] The core innovation of the utility model lies in that the first stamping piece and the second stamping piece in petal shape are combined as a planetary gear retainer. This design not only simplifies the manufacturing process and reduces the cost, but also effectively controls the position and movement of the planetary gear. Moreover, the slight elastic deformation characteristics of the stamping part are ingeniously utilized to improve the system performance. During the transmission process, the load fluctuation can be absorbed and the tooth surface contact stress can be reduced through the elastic deformation characteristics of the stamping part, thereby improving the running stability and service life of the system. At the same time, this elastic property can also compensate for the slight errors in the manufacturing and assembly process, thereby improving the load sharing performance of the system. This feature is particularly important in high-precision application scenarios, such as robot joint reducers.

[0036] Therefore, the utility model not only solves the problem of fixed connection of the planetary gear mechanism stamping retainer, but also improves the stability and reliability of the overall structure. Compared with the traditional bolt connection or single welding method, the scheme of the utility model has higher connection strength and better assembly accuracy. This design also simplifies the structure of the retainer, reduces the number of parts, is conducive to reducing the manufacturing and assembly cost, and can also improve the anti-vibration performance and service life of the retainer, thereby providing a reliable guarantee for the stable operation of the planetary gear mechanism.

[0037] Embodiment 2

[0038] On the basis of embodiment 1, this embodiment further proposes that the central holes of the first stamping piece and the second stamping piece are each provided with an outer convex part to increase the strength of the central hole and help reduce vibration and deformation during operation and improve stability. The planet gear shaft holes 5 of the first stamping piece and the second stamping piece are each provided with an inner convex support part, which provides better support and positioning function for the planetary gear, ensures that the planetary gear maintains a stable position during operation, and also helps to reduce the contact area between the planet carrier and the planet wheel end face, thereby reducing the friction force of the contact surface and the wear of the contact surface. Therefore, the overall strength of the retainer of the utility model is greatly improved, and the radial and axial movement of the planetary gear is reduced, thereby reducing the noise and vibration during gear meshing, which can better adapt to high-speed and high-load working conditions and help to prolong the service life of the entire planetary gear mechanism.

[0039] Embodiment 3

[0040] This embodiment is further proposed on the basis of embodiment 2 that the connecting piece is provided with a rib-shaped stamping groove 7.

[0041] The design of the rib-shaped stamping groove 7 brings additional advantages. First, it not only enhances the strength and stiffness of the connecting piece itself while reducing the weight, but also improves the overall stiffness and stability of the entire cage. Further, the rib-shaped stamping groove increases the sectional moment of inertia of the connecting piece, significantly improving the bending and torsional resistance of the connecting piece. This structural optimization enables the cage to maintain good stability and reliability under high-speed operation and heavy load conditions. Furthermore, the rib-shaped stamping groove improves the heat dissipation performance of the cage, which is beneficial to reduce thermal deformation during operation.

[0042] Compared with the traditional flat connecting piece, the connecting piece provided with the rib-shaped stamping groove greatly reduces the deformation under the same load conditions and improves the service life. This innovative design not only solves the problem of insufficient strength of the connecting piece, but also brings comprehensive performance improvement to the entire cage structure.

[0043] Embodiment 4

[0044] In the above embodiments, there is also a problem of adaptation between the double planetary gear and the connecting piece of the cage. To this end, this embodiment is further proposed on the basis of embodiment 3 that the connecting piece is provided with a stepped structure, the lower part size is larger than the upper part size, as shown in Figure 2 、 4 and 5 to adapt to the double planetary gear.

[0045] The traditional planetary gear cage usually adopts connecting pieces with equal width, and this design often has the problem of insufficient support or excessive interference when adapting to the double planetary gear. The utility model can improve the matching precision between the cage and the double planetary gear, reduce the gap, thereby improving the operation stability and transmission efficiency of the entire planetary gear mechanism, and also can provide better support, and also can reduce the use of materials and reduce the overall weight. Specifically, the design of the larger lower part size can provide a larger support area for the double planetary gear, effectively reducing the shaking of the gear during operation, and the design of the smaller upper part size can reduce the interference with the double planetary gear, ensuring smooth operation of the double planetary gear.

[0046] Embodiment 5

[0047] This embodiment is based on embodiment 4, and the number n of connecting pieces and planetary gear shaft holes 5 is limited to 3-5. This design scheme limits the number of connecting pieces and planetary gear shaft holes 5 to 3-5, avoiding the complexity brought by too many double planetary gears and the decrease of the connecting strength of the connecting piece.

[0048] As preferred, n=4 is selected for use in the robot joint reducer. This configuration can maintain the symmetry and balance of the structure while providing sufficient support force. Specifically, the four connecting pieces can be evenly distributed in the circumference of the retainer to form a square structure to provide sufficient strength and rigidity.

[0049] The above merely describes the embodiments of the present application and is not used to limit the protection scope of the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A 3K planetary gear mechanism press-retained cage, characterized by: First stamping sheet and second stamping sheet, the first stamping sheet is composed of a flat plate part and a plurality of connecting pieces which are evenly distributed in the circumferential direction, the connecting pieces are bent to be 90° with the flat plate part, and the first stamping sheet as a whole is in the shape of a petal; the connecting pieces are provided with tenons, the second stamping sheet is provided with tenon holes equal in number to the connecting pieces, each tenon is connected with a corresponding tenon hole, or each tenon is connected with a corresponding tenon hole while being welded; the flat plate part of the first stamping sheet and the center of the second stamping sheet are both provided with a central hole which penetrates the flat plate part or the second stamping sheet; the flat plate part of the first stamping sheet and the second stamping sheet are both provided with three or more planetary gear shaft holes which are evenly distributed in the circumferential direction outside the respective central holes.

2. A 3K planetary gear mechanism stamping retainer according to claim 1, characterized in that: The number of the connecting pieces and the planetary gear shaft holes is equal, one planetary gear shaft hole is arranged between every two adjacent connecting pieces, and one planetary gear shaft hole is arranged between every two adjacent tenon holes.

3. A 3K planetary gear mechanism stamping retainer according to claim 1 or 2, characterized in that: The central holes of the first stamping sheet and the second stamping sheet are both provided with an outward protruding part, and each planetary gear shaft hole of the first stamping sheet and the second stamping sheet is provided with an inward protruding supporting part.

4. A 3K planetary gear mechanism stamping retainer according to claim 1 or 2, characterized in that: The connecting pieces are provided with a muscle-shaped stamping groove.

5. A 3K planetary gear mechanism stamping retainer according to claim 1 or 2, characterized in that: The connecting pieces are provided with a stepped structure, the lower part is larger in size than the upper part.

6. A 3K planetary gear mechanism stamping retainer according to claim 1 or 2, characterized in that: The number of the connecting pieces and the planetary gear shaft holes is limited to the range of 3-5.

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