Gear transmission structure of high-precision robot joint

Abstract

The utility model provides a kind of high-precision robot joint gear transmission structure, it is related to planetary gear technical field, comprising: three planetary gear sets, each planetary gear set includes two gears connected and coaxially arranged, two gears are respectively gear located above as first planetary gear and gear located below as second planetary gear, the first planetary gear and the second planetary gear are all unevenly distributed gear number gear, first flat side and second flat side are respectively provided on the second planetary gear and the first planetary gear;Planet carrier.The utility model has beneficial effects: by adopting three planetary gear sets and the first planetary gear and the second planetary gear are all unevenly distributed gear number gear, and first flat side and second flat side are respectively set on it, cooperate with the mark on planet carrier, the accurate tooth and meshing of planetary gear set are realized, effectively improve transmission accuracy, reduce error accumulation, ensure the high-precision control of robot joint movement.

Description

Technical Field

[0001] This utility model relates to the field of planetary gear technology, and in particular to a gear transmission structure for a high-precision robot joint. Background Technology

[0002] High-precision robot joint gear transmission generally adopts a planetary gear transmission structure. In the gear structure of gears with non-uniformly distributed teeth (the number of teeth is not a multiple of 3), the planetary gears are aligned with the sun gear in the gear ring. The relative angles are not at the corresponding positions of 120 degrees, that is, there will be a certain offset from the 120° relative position. Therefore, when assembling the gear structure, it is necessary to perform precise tooth alignment operations between the planetary gears and the gear ring and sun gear.

[0003] In existing gear transmission systems, the accuracy of gear alignment directly affects the meshing effect and transmission efficiency of gears. Traditional gear alignment methods usually rely on precise control during machining and assembly, but this method often has the following problems: First, it requires high precision in machining and assembly, which increases production costs; second, it is difficult to make precise gear alignment adjustments after gear installation. Once the gear alignment is inaccurate, it may be necessary to disassemble and reinstall the gear, which increases maintenance costs and time. Utility Model Content

[0004] In view of this, the embodiments of this utility model provide a high-precision gear transmission structure for robot joints to solve the technical problems of difficult gear matching and inconvenient gear accuracy adjustment in existing gear transmission structures.

[0005] An embodiment of this utility model provides a high-precision gear transmission structure for a robot joint, comprising:

[0006] Three planetary gear sets, each planetary gear set includes two gears connected vertically and coaxially, the upper gear being the first planetary gear and the lower gear being the second planetary gear, both the first planetary gear and the second planetary gear being gears with unevenly distributed teeth, and the second planetary gear and the first planetary gear being respectively provided with a first flat edge and a second flat edge;

[0007] A planetary carrier, wherein a sun gear is provided in the middle of the planetary carrier, and three planetary gear sets are equally spaced on the planetary carrier, and the three first planet gears of the three planetary gear sets are all meshed with the sun gear;

[0008] And a gear ring, which simultaneously meshes with the third second planetary gear, the gear ring having a mark on its exterior, the mark being in the same radial direction as the first flat edge;

[0009] The midpoint of the first flat edge and the root of one tooth of the second planetary gear are on the same straight line in the radial direction of the second planetary gear. The second flat edge is configured such that when the first planetary gear meshes with the sun gear, its midpoint, the sun gear axis, and a marked point are on the same straight line.

[0010] Furthermore, the first planetary gear is also marked, and the mark on the first planetary gear is in the same radial direction as the center of the second flat edge.

[0011] Furthermore, a shaft is rotatably connected at the center of the planetary carrier, and the sun gear is disposed outside the shaft.

[0012] Furthermore, the planetary carrier is provided with ball bearings, the outer ring of the ball bearings is connected to the planetary carrier, and the inner ring of the ball bearings is connected to the shaft.

[0013] Furthermore, the planetary carrier has three cylindrical pins that rotate around the axis at equal intervals in the circumferential direction.

[0014] Furthermore, the second planetary gear is provided with a pin, and a semi-circular groove is provided at the center of the first planetary gear shaft, and the pin is inserted into the semi-circular groove.

[0015] Furthermore, a through hole is provided in the center of the pin, through which the first planetary gear is connected by the cylindrical pin.

[0016] Furthermore, a gasket is provided on the outside of the cylindrical pin between the second planetary gear and the planet carrier.

[0017] Furthermore, the cylindrical pin is press-fitted onto the planetary carrier.

[0018] The beneficial effects of the technical solution provided by the embodiments of this utility model are as follows: The gear transmission structure of the high-precision robot joint of this utility model adopts three planetary gear sets, with the first and second planetary gears being non-uniformly distributed tooth gears, and first and second flat edges respectively set on them. In conjunction with the markings on the planetary carrier, the precise tooth alignment and meshing of the planetary gear sets are achieved, effectively improving the transmission accuracy, reducing error accumulation, and ensuring high-precision control of the robot joint movement; the planetary carrier is connected to the shaft through ball bearings, which reduces friction, improves transmission efficiency, and ensures stable rotation of the planetary carrier; the meshing of the gear ring with the three second planetary gears further optimizes the transmission ratio, making the entire transmission system more coordinated and efficient, and meeting the requirements of high-precision robot joints for load-bearing capacity and response speed. Attached Figure Description

[0019] Figure 1This is a schematic diagram of the gear transmission structure of the high-precision robot joint of this utility model;

[0020] Figure 2 This is an assembly top view of the gear transmission structure of the high-precision robot joint of this utility model;

[0021] Figure 3 This is a schematic diagram of an embodiment of the gear transmission structure of the high-precision robot joint of this utility model;

[0022] Figure 4 This is a perspective view of the second planetary gear structure of the high-precision robot joint gear transmission structure of this utility model.

[0023] In the diagram: 1. Planet carrier; 2. Shaft; 3. Sun gear; 4. Ball bearing; 5. Gear ring; 6. Cylindrical pin; 7. First planet gear; 8. Second planet gear; 9. Pin; 901. First flat edge; 10. Washer; 11. Semicircular groove; 1101. Second flat edge; 12. Marking. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be further described below with reference to the accompanying drawings. The following description presents a preferred embodiment of several possible embodiments of this utility model, intended to provide a basic understanding of the utility model, but not intended to identify the key or decisive elements of the utility model or to limit the scope of protection sought.

[0025] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0026] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures. Also, it should be understood that, for ease of description, the dimensions of the various parts shown in the figures are not drawn to actual scale.

[0028] In the description of this utility model, it should be noted that the circuits, electronic components and modules involved in this utility model are all existing technologies, which can be fully implemented by those skilled in the art, and need not be elaborated. The content protected by this utility model does not involve any improvement to the internal structure and method.

[0029] It should be further noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0030] Please refer to Figure 1 The present invention provides a gear transmission structure including three planetary gear sets, a planet carrier 1 and a gear ring 5. Each planetary gear set consists of a first planetary gear 7 and a second planetary gear 8 connected vertically. The first planetary gear 7 and the second planetary gear 8 are both gears with unevenly distributed teeth. All three planetary gear sets are mounted on the planet carrier 1.

[0031] It should be noted that the sun gear 3 is installed in the middle of the planet carrier 1, and the first planet gear 7 of the three planet gear set is meshed with the sun gear 3. In order to ensure the precise positioning of the planet gear set on the planet carrier 1, the second planet gear 8 and the first planet gear 7 are respectively provided with a first flat edge 901 and a second flat edge 1101. A mark 12 is provided on the outside of the gear ring 5, and the mark 12 is on the same radial direction as the first flat edge 901.

[0032] In an optional embodiment, a central shaft 2 is rotatably connected to the center of the planet carrier 1, and the sun gear 3 is disposed outside the central shaft 2. The rotatable connection between the planet carrier 1 and the central shaft 2 is achieved by a ball bearing 4.

[0033] Specifically, the planetary carrier 1 is equipped with a ball bearing 4. The outer ring of the ball bearing 4 is connected to the planetary carrier 1, and the inner ring is connected to the central shaft 2. The ball bearing 4 can effectively reduce the friction between the planetary carrier 1 and the central shaft 2, improve the transmission efficiency, and at the same time ensure that the planetary carrier 1 can rotate stably around the central shaft 2, providing reliable support and guidance for the normal operation of the entire gear transmission structure.

[0034] In the specific implementation process, firstly, the three second planetary gears 8 are simulated to mesh with the gear ring 5. Any tooth tip of one second planetary gear 8 is meshed with any tooth root of the gear ring 5, and a mark 12 is set at the meshing point of the gear ring 5. Then, the other two second planetary gears 8 are set on the planet carrier 1, and the tooth roots corresponding to the center of the two first flat edges 901 of the gear ring 5 and the two second planetary gears 8 are meshed. Marks 12 are set at the two meshing points.

[0035] Specifically, the midpoint of the first flat edge 901 and the root of one tooth of the second planetary gear 8 are on the same straight line in the radial direction of the second planetary gear 8. The second flat edge 1101 is configured such that when the first planetary gear 7 meshes with the sun gear 3, its midpoint, the axis of the sun gear 3, and the mark 12 are on the same straight line.

[0036] In order to evenly arrange the three planetary gear sets on the planet carrier 1, three cylindrical pins 6 are rotatably mounted on the planet carrier 1. The three cylindrical pins 6 are evenly spaced around the central shaft 2 in the circumferential direction. That is to say, the three cylindrical pins 6 are evenly arranged at an angle of 120 degrees relative to each other, so that the three planetary gear sets maintain good balance and stability during rotation.

[0037] Furthermore, the second planetary gear 8 is provided with a pin 9, and the first planetary gear 7 has a semi-circular groove 11 at its shaft center. The first flat edge 901 is provided on the pin 9, and the second flat edge 1101 is provided on the semi-circular groove 11. The pin 9 is inserted into the semi-circular groove 11, which restricts the relative rotation of the first planetary gear 7 and the second planetary gear 8. Therefore, the first planetary gear 7 and the second planetary gear 8 have only one installation direction.

[0038] In addition, a through hole is provided in the center of the pin 9, through which the first planetary gear 7 is passed by the cylindrical pin 6, thereby fixing the planetary gear set to the cylindrical pin 6.

[0039] In another optional embodiment, in order to further enhance the reliability and stability of the connection, a gasket 10 is provided on the outside of the cylindrical pin 6, between the second planetary gear 8 and the planet carrier 1. The gasket 10 can evenly distribute the pressure and prevent loosening.

[0040] During the assembly process, the pin 9 of the planetary gear set is first aligned and inserted with the semi-circular groove 11 of the first planetary gear 7, and then the cylindrical pin 6 is pressed onto the planet carrier 1 to complete the installation of the planetary gear set.

[0041] Please refer to Figure 2 In this embodiment, the midpoint of the first flat edge 901, the center point of the sun gear 3, and the center point of the cylindrical pin 6 are on the same straight line. Thus, the meshing tooth tip position of the three second planetary gears 8 and the gear ring 5 can be determined by the orientation of the first flat edge 901.

[0042] In this embodiment, the midpoint of the second flat edge 1101, the axis of the sun gear 3, and the axis of the cylindrical pin 6 are on the same straight line. Since the first planetary gear 7 and the sun gear 3 are meshed at this time, when the second flat edge 1101 and the first flat edge 901 are in the same orientation position, the first planetary gear 7 and the second planetary gear 8 are respectively aligned with the sun gear 3 and the gear ring 5. It can be understood that when the first planetary gear 7 and the second planetary gear 8 are connected according to the alignment of the first flat edge 901 and the second flat edge 1101, the first planetary gear 7 and the second planetary gear 8 can simultaneously meet the alignment requirements with the sun gear 3 and the gear ring 5, so there is no need to make subsequent adjustments to the alignment of the first planetary gear 7 or the second planetary gear 8.

[0043] In addition, a mark 12 is also provided on the first planetary gear 7. The mark 12 is in the same radial direction as the center of the second flat edge 1101. The setting of these marks 12 and the first flat edge 901 and the second flat edge 1101 makes it easy to quickly and accurately determine the installation position and angle of the planetary gear set during the assembly process, ensuring the correct meshing relationship between each gear and improving the assembly accuracy and transmission stability of the entire transmission structure.

[0044] The gear ring 5 meshes with three second planetary gears 8 simultaneously. The configuration of the gear ring 5 provides another important meshing point for the planetary gear set. Together with the sun gear 3, it forms a planetary gear transmission system, which meets the joint performance requirements of high-precision robots.

[0045] In one specific embodiment:

[0046] The gear-setting process is simulated using software: In this embodiment, the first planetary gear 7 has 49 teeth, the second planetary gear 8 has 22 teeth, the gear ring 5 has 74 teeth, and the sun gear 3 has 10 teeth. First, a second planetary gear 8 is placed on the cylindrical pin 6 so that one of its tooth tips meshes with any tooth root of the gear ring 5. Marks 12 are set at the meshing points of the gear ring 5 and the second planetary gear 8. Then, two more second planetary gears 8 are placed on their respective cylindrical pins 6 so that both second planetary gears 8 mesh with the gear ring 5 to complete the gear-setting process. Marks 12 are set at the meshing points of the gear ring 5 and the gear ring 5.

[0047] Then, simulate the first planetary gear 7 teeth. Place one first planetary gear 7 on the cylindrical pin 6, aligning its tooth tip with mark 12. Then place the sun gear 3 at the center of the planet carrier 1, so that the tooth tip of the sun gear 3 meshes with the tooth root of the first planetary gear 7. At this time, the tooth tips of the first planetary gear 7 and the second planetary gear 8 and the tooth roots of the sun gear 3 and the gear ring 5 are on a straight line. This planetary gear set is used as a standard set. Place the other two first planetary gears 7 on their respective cylindrical pins 6 and adjust the two first planetary gears 7 so that they mesh with the sun gear 3. Since the first planetary gear 7 and the second planetary gear 8 are non-uniformly distributed gears, the angle between their meshing tooth roots or tooth tips with the gear ring 5 and the sun gear 3 is not 120°. At this time, the orientation of the second flat side 1101 can be determined by using mark 12 and the axis of the cylindrical pin 6 as a vertical line.

[0048] Based on the simulation results, the positions of the pin 9 and the semi-circular groove 11 are machined for the first planetary gear 7 and the second planetary gear 8 that are actually machined. The first planetary gear 7 and the second planetary gear 8 are then assembled by inserting the pin 9 and the semi-circular groove 11. Since the teeth have been aligned in advance, the installation can be completed simply by aligning the first flat edge 901 or the second flat edge 1101 with the mark 12 on the gear ring 5.

[0049] In this document, the directional terms such as front, back, top, and bottom are defined based on the position of the components in the accompanying drawings and their relative positions to each other, solely for the purpose of clarity and convenience in expressing the technical solution. It should be understood that these are relative concepts and can vary depending on different methods of use and placement; the use of these directional terms should not limit the scope of protection claimed in this application.

[0050] Where there is no conflict, the above embodiments and features described herein can be combined with each other.

[0051] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A high-precision gear transmission structure for a robot joint, characterized in that, include: Three planetary gear sets, each planetary gear set includes two gears connected vertically and coaxially, the upper gear being the first planetary gear (7) and the lower gear being the second planetary gear (8), the first planetary gear (7) and the second planetary gear (8) are both gears with non-uniformly distributed teeth, the second planetary gear (8) and the first planetary gear (7) are respectively provided with a first flat edge (901) and a second flat edge (1101). A planetary carrier (1) is provided with a sun gear (3) in the middle of the planetary carrier (1). Three planetary gear sets are equally spaced on the planetary carrier (1), and the three first planetary gears (7) of the three planetary gear sets are all meshed with the sun gear (3). And a gear ring (5), which simultaneously meshes with three second planetary gears (8), the gear ring (5) having a mark (12) on its exterior, the mark (12) being in the same radial direction as the first flat edge (901); The midpoint of the first flat edge (901) and the root of a tooth of the second planetary gear (8) are on the same straight line in the radial direction of the second planetary gear (8). The second flat edge (1101) is configured such that when the planetary gear (7) meshes with the sun gear (3), its midpoint, the axis of the sun gear (3), and the mark (12) are on the same straight line.

2. The gear transmission structure for a high-precision robot joint as described in claim 1, characterized in that: The first planetary gear (7) is also marked (12), and the mark (12) on the first planetary gear (7) is in the same radial direction as the center of the second flat edge (1101).

3. The gear transmission structure for a high-precision robot joint as described in claim 1, characterized in that: The planetary carrier (1) is rotatably connected to a shaft (2) at its center, and the sun gear (3) is located outside the shaft (2).

4. The gear transmission structure for a high-precision robot joint as described in claim 3, characterized in that: The planetary carrier (1) is provided with a ball bearing (4), the outer ring of the ball bearing (4) is connected to the planetary carrier (1), and the inner ring of the ball bearing (4) is connected to the shaft (2).

5. The gear transmission structure for a high-precision robot joint as described in claim 3, characterized in that: Three cylindrical pins (6) rotate on the planetary carrier (1), and the three cylindrical pins (6) are evenly spaced around the axis (2) in the circumferential direction.

6. The gear transmission structure for a high-precision robot joint as described in claim 5, characterized in that: The second planetary gear (8) is provided with a pin (9), and the first planetary gear (7) has a semi-circular groove (11) at the shaft center. The pin (9) is inserted into the semi-circular groove (11).

7. The gear transmission structure for a high-precision robot joint as described in claim 6, characterized in that: The center of the pin (9) has a through hole through which the first planetary gear (7) is connected by the cylindrical pin (6).

8. The gear transmission structure for a high-precision robot joint as described in claim 5, characterized in that: The cylindrical pin (6) is provided with a gasket (10) located between the second planetary gear (8) and the planet carrier (1).

9. The gear transmission structure for a high-precision robot joint as described in claim 6, characterized in that: The cylindrical pin (6) is press-fitted onto the planetary carrier (1).

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