Large-torque triangular prism mechanical transmission connection method

Abstract

The invention discloses a large-torque triangular prism mechanical transmission connection method, and relates to the technical field of mechanical transmission connection, and the method comprises the following steps: S1, preparing a rotating part and a cylindrical connecting rod; s2, the rotating part is fixed to a high-precision numerical control machine tool, and a triangular prism is machined through rotation of a main shaft and matching of radial feeding and axial feeding of a tool; the triangular prism structure is adopted for connection, the defects that traditional key connection is prone to deformation and looseness, and maintenance and disassembly are difficult are overcome, reliable connection is achieved, torque of 200 N.m or more can be borne, positioning and looseness prevention are achieved, return difference does not exist, torque is accurately transmitted, the structure is compact, plug and play is achieved, assembly errors and assembly time are reduced, and the machining cost is low; and the device is suitable for various mechanical types needing large-torque stable transmission, the design concept can also extend to other prism transmission connection, and the application prospect is wide.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical transmission connection, and in particular to a large-torque 3-prism mechanical transmission connection method. Background Art

[0002] In the field of mechanical transmission connection technology, reliable and efficient high-torque transmission connection has always been the focus and difficulty of research. Traditional transmission connection methods, such as key connection (refer to "Mechanical Design Manual", Machinery Industry Press, 2010 edition, which details the structure, working principle and application scenarios of key connection), are mainly composed of keys, shafts and hubs, and the torque is transmitted by the mutual extrusion between the side of the key and the side of the keyway of the shaft and hub.

[0003] In practical applications, traditional key connections expose many problems when facing high torque requirements. The disadvantages of traditional key connections are particularly prominent in scenarios such as heavy-duty machinery (such as large-scale mining equipment), high-vibration machinery (such as vibrating screens), industrial robot joint motors that have strict requirements for large torque stable transmission, and valve plate drives in the valve industry. For example, in the field of industrial robot joint motors, with the continuous improvement of industrial automation, the requirements for robot motion accuracy and load capacity continue to increase. However, after the traditional key connection is subjected to large torques many times, the keys and keyways are very likely to deform, causing the connection to loosen, affecting transmission efficiency and stability. This is because the contact area of ​​the key connection is limited. Under the action of high torque, the local stress concentration phenomenon is serious, causing the surface of the key and keyway to gradually wear and deform. This not only causes problems such as inaccurate positioning and motion jams when the robot performs tasks, but also increases the maintenance cost and downtime of the equipment. According to statistics, the average downtime and maintenance time of industrial robots caused by key connection failures can reach several hours or even longer each time, seriously affecting production progress.

[0004] In the valve plate drive of the valve industry, the traditional connection method is also prone to failure under long-term high torque and frequent switching operations. The normal operation of the valve is crucial to the stability of the entire industrial production process, and the reliability of the traditional key connection is insufficient, which may cause the valve to have inaccurate movement and delay during the opening and closing process, thus affecting the continuity and stability of the entire industrial production.

[0005] At present, although there are some technical improvement schemes for mechanical transmission connections, there are still certain limitations. Although some schemes can improve the connection strength to a certain extent, the processing technology is complicated and the cost is high. For example, some connection methods that use special forging processes and high-precision grinding processes have a processing cost that is about 3 times higher than that of traditional processes, which limits large-scale applications. Some other schemes are lacking in connection accuracy and stability and cannot meet the transmission requirements of high precision and high torque. In the power transmission scenarios of high-precision automated production lines, these improvement schemes are difficult to meet the equipment's requirements for stable torque transmission and high-precision motion control, resulting in reduced production accuracy and difficulty in ensuring product quality.

[0006] In summary, the existing mechanical transmission connection technology, especially the traditional key connection method, has many shortcomings in terms of reliability, accuracy and cost-effectiveness of large torque transmission, and it is difficult to meet the growing needs of modern industry. A new technical solution is urgently needed to solve these problems.

[0007] In view of this, a high-torque 3-prism mechanical transmission connection method is provided to overcome the above problems. Summary of the invention

[0008] The purpose of the present invention is to provide a large torque 3-prism mechanical transmission connection method to solve the problems raised in the above background technology.

[0009] In order to solve the above technical problems, the present invention provides a high-torque 3-prism mechanical transmission connection method, comprising the following steps:

[0010] S1: Preparation of rotating parts and cylindrical connecting rods;

[0011] S2: Processing the prismatic shaft hole of the rotating part: Fix the rotating part on a high-precision CNC machine tool, set the milling speed to n1 rpm, and the feed rate to f1 mm / rev;

[0012] S3: After the shaft hole of the prism is processed, the rotating part is re-clamped on the drilling machine. At the top of the shaft hole of the prism, the drill speed is set to n2 rpm and the feed rate is f2 mm / rev to process the positioning threaded hole. The depth error of the positioning threaded hole is controlled within ±0.2 mm.

[0013] S4: Place the cylindrical connecting rod on a non-circular CNC lathe. When processing it into a triangular prism shape, the main shaft is also used to drive the cylindrical connecting rod to rotate. At the same time, the radial feed of the tool is coordinated with the axial feed. Through multiple tool-pass turning processes, the first tool-pass cutting amount is a1 mm, and each subsequent tool-pass decreases by a2 mm. The lathe X, Z, and C three-axis linkage method is used to process it into a triangular prism shape, and the contour of the triangular prism is controlled within 0.01 mm; at the same time, the X, Z, and S linkage method is used to process the wave bead arc groove;

[0014] S5: Insert the processed and coated transmission shaft of the mitre column into the shaft hole of the mitre column of the rotating part, and then screw the positioning ball screw through the positioning threaded hole so that its end is embedded in the arc keyway of the transmission shaft of the mitre column.

[0015] Furthermore, in S2, the spindle drives the rotating part to rotate at a stable speed of n1 rpm, and the tool gradually cuts in along the radial direction according to the designed inner diameter of the shaft hole, and at the same time moves axially to complete the milling of the entire shaft hole; according to the shaft hole inner diameter size tolerance controlled at ±0.01mm and the surface roughness Ra≤0.8μm, the milling function is used to machine the shaft hole of the mitre.

[0016] Furthermore, the invention is suitable for heavy-load machinery, high-vibration machinery and other types of machinery requiring stable transmission of large torque.

[0017] Furthermore, it is suitable for torque transmission in compact structures and small spaces, including but not limited to output power transmission of robot joint motors.

[0018] Furthermore, it is suitable for high precision and no hysteresis.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. Strong connection reliability and excellent torque bearing capacity: In terms of component materials and preparation, the rotating parts are made of high-strength aluminum alloy combined with precision casting technology, and the cylindrical connecting rods are forged with high-quality alloy steel. The use of high-strength aluminum alloy reduces the weight of the rotating parts while ensuring strength, reduces the inertia load of the robot joints, and improves the motion response speed; precision casting accurately controls the size and shape of parts, reduces internal defects, and provides a good foundation for subsequent processing. After forging, the internal structure of high-quality alloy steel is dense, which improves the comprehensive mechanical properties of the cylindrical connecting rod, enabling it to effectively bear complex stress. In the processing link, the inner diameter size tolerance of the shaft hole is controlled within ±0.01mm, the contour of the prismatic column is controlled within 0.01mm, and the depth error of the positioning threaded hole is controlled within ±0.2mm. This high-precision processing realizes the close fit between the shaft hole and the transmission shaft, and the precise collaboration between the positioning threaded hole and the positioning ball screw. In practical applications, the following are examples: When the motor of an industrial robot joint is subjected to a torque of 200 N·m, the traditional connection method may loosen or deform due to insufficient component strength and matching accuracy. However, this method can stably carry loads, and the torque carrying capacity is greatly improved compared to the traditional method, ensuring stable operation of the equipment under harsh working conditions such as heavy loads and high speeds, reducing the risk of failures, and ensuring the continuity and stability of industrial production. In addition, the anti-loosening design of the positioning threaded hole and the positioning ball screw enhances the reliability of the connection and further ensures stable torque transmission under complex working conditions.

[0021] 2. Extremely high connection accuracy, eliminating reverse clearance: From the shaft hole, triangular prism to the threaded hole and arc keyway, the entire processing process maintains high precision, especially the contour of the triangular prism is controlled at 0.01mm. This high-precision processing ensures precise matching between components and effectively avoids the reverse clearance problem common in traditional connection methods. When the robot performs precision assembly, welding and other tasks, the reverse clearance of the traditional connection will lead to a decrease in motion accuracy, making the position and posture control of the end effector inaccurate, affecting product quality. This method can achieve precise torque transmission, ensure the accuracy of robot joint motion, ensure the precise position and posture control of the end effector, improve product quality and production efficiency, reduce scrap rate, and thus enhance the economic benefits and market competitiveness of the enterprise.

[0022] 3. Compact structural design, convenient and efficient assembly: The overall structural design is compact and reasonable, the connection of components is simple and efficient, and it occupies a small space. It is especially suitable for torque transmission scenarios with compact structure and small space, such as robot joint motors. Compared with the traditional complex transmission connection structure, the compact structure of this method is more suitable for application scenarios with limited space, which is convenient for installation and layout, and will not affect the flexibility of the equipment due to excessive volume. In terms of assembly, it can be assembled directly after processing, and it is plug-and-play. The traditional connection method has a complicated assembly process, requires professional tools and is prone to assembly errors. The convenient assembly of this method not only saves time and labor costs for on-site assembly of industrial robots, but also reduces the risk of errors caused by improper assembly, and improves production and maintenance efficiency. During daily maintenance and fault repair of equipment, damaged parts can be quickly replaced, which shortens downtime, improves equipment utilization, and reduces enterprise operating costs.

[0023] 4. Wide application fields and huge expansion potential: This method is not only suitable for torque transmission of industrial robot joint motors, but can also be widely used in other types of machinery that require large torque and stable transmission. In the power transmission of automated production lines, it can ensure stable operation of equipment and improve production efficiency; in the transmission systems of some special machinery, it can meet the needs of special working conditions with its large torque bearing capacity and high precision. Including: In the valve plate drive of the valve industry, compared with the traditional connection method, this method can make the torque transmission during the opening and closing of the valve more stable, ensure the valve action is reliable and accurate, and is suitable for occasions with high requirements for valve response speed and stability. In addition, the design concept of this method can be extended to the transmission connection of triangular prisms, ellipses or more prisms, providing innovative solutions for power transmission in different industrial fields, promoting the diversified development of industrial machinery transmission technology, and showing broad application prospects and promotion value.

[0024] 5. Break through tradition and solve industry problems: The present invention realizes one-piece molding of the connecting rod by optimizing the processing technology, which effectively solves the problem that the key and keyway are deformed and difficult to disassemble and repair after repeated use of the traditional key connection. After the traditional key connection is subjected to large torque for a long time, the key and keyway are prone to wear and deformation, and it is difficult and costly to disassemble during maintenance. The triangular column conductive contact surface adopted in this method is an integral contact, which greatly increases the torque transmission capacity compared to the traditional connection method, and is particularly suitable for mechanical transmission at large torque connections. This innovative design provides a new, efficient, reliable and durable solution for power transmission in the industrial field, promotes the advancement of industrial mechanical transmission technology, and provides strong support for the efficient and stable operation of industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of a high-torque 3-prism mechanical transmission connection method of the present invention;

[0026] Figure 2 This is an explosion effect diagram of a high-torque 3-prism mechanical transmission connection method of the present invention;

[0027] Figure 3 It is a schematic diagram of the connection structure between a transmission shaft and a positioning ball screw in a large torque prismatic column mechanical transmission connection method of the present invention.

[0028] In the figure: 1. rotating part; 2. transmission shaft; 3. positioning ball screw; 4. shaft hole; 5. positioning threaded hole; 6. arc keyway. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] See also Figure 1-Figure 3 , the present invention provides a technical solution:

[0031] See also Figure 1-Figure 3 As shown, an embodiment of a large torque 3-prism mechanical transmission connection method:

[0032] This embodiment takes the torque transmission scenario of the robot joint motor as an example to explain in depth a high-torque 3D-column mechanical transmission connection method. During the operation of the robot, the joint motor needs to stably and efficiently transmit large torque. Its operating conditions are complex, including frequent start and stop, high-speed operation, and large external force impact, which puts forward strict requirements on the reliability and accuracy of the transmission connection. This method can meet these requirements excellently.

[0033] 1. Preparation of rotating part 1 and cylindrical connecting rod

[0034] When the robot joint motor is running, the rotating parts will be subjected to large torque and dynamic load, and need to have good motion response performance. High-strength aluminum alloy has a high specific strength, which can reduce weight while ensuring strength, just in line with the needs of reducing robot joint load and improving motion response speed. Using precision casting technology, the size and shape of parts can be accurately controlled, effectively reducing internal defects, thereby ensuring the quality of rotating parts.

[0035] As a key component for torque transmission, cylindrical connecting rods must have high tensile strength and good toughness to withstand the complex stress during large torque transmission. After forging, the internal structure of high-quality alloy steel will become dense and the grains will be refined, which will significantly improve the comprehensive mechanical properties of the material.

[0036] The rotating part 1 is made of high-strength aluminum alloy and prepared by precision casting process, which has a reduced weight, which can effectively reduce the inertial load of the robot joint, thereby improving the motion response speed and making the industrial robot more agile when performing tasks. The dimensional accuracy and surface quality guaranteed by precision casting provide a good foundation for subsequent high-precision processing, reduce processing allowances, and improve processing efficiency. The cylindrical connecting rod, which is initially formed by the forging process of high-quality alloy steel, has high tensile strength and good toughness, and can effectively bear complex stresses such as tensile stress and shear stress in the process of large torque transmission, ensuring stable and reliable transmission of torque under complex working conditions of industrial robots.

[0037] 2. Processing the triangular column shaft hole 4 of the rotating part 1

[0038] In order to achieve high-precision and high-stability torque transmission of the industrial robot joint motor, the matching accuracy of the shaft hole and the drive shaft is very important. High-precision CNC machine tools have high positioning accuracy and motion accuracy, and can accurately control the spindle speed and the feed movement of the tool. By setting the milling speed to n1 rpm and the feed rate to f1 mm / rev, the cutting process of the tool on the rotating part 1 can be accurately controlled. The inner diameter size tolerance of the shaft hole is controlled at ±0.01mm, which can ensure high-precision transition fit with the Mitsubishi column drive shaft 2, reduce the fit clearance, and improve the accuracy of torque transmission.

[0039] With the help of high-precision CNC machine tools, with precisely set speed and feed rate, high-precision milling of the shaft hole is achieved. The extremely small shaft hole inner diameter tolerance ensures a close fit with the Mitsubishi column drive shaft 2, effectively reducing the fit clearance, avoiding torque transmission errors and vibrations caused by the clearance, improving the accuracy and stability of torque transmission, and meeting the strict requirements of industrial robots for high-precision and high-stability torque transmission.

[0040] 3. Processing positioning threaded holes 5

[0041] During the operation of the joint motor of the industrial robot, the transmission shaft and the rotating part need to maintain a stable relative position to prevent the torque transmission accuracy and stability from being affected by relative displacement. By machining the positioning threaded hole 5 at the top of the Mitsubishi column shaft hole 4 and cooperating the positioning ball screw 3 with the arc keyway 6 on the transmission shaft 2, reliable positioning and anti-loosening functions can be achieved. Controlling the depth error of the positioning threaded hole within ±0.2mm can ensure that after the positioning ball screw 3 is installed, its end is accurately embedded in the arc keyway 6, achieving the best positioning and anti-loosening effect.

[0042] The positioning threaded hole 5 with precise control of the depth error ensures the accuracy of the installation position of the positioning ball screw 3, so that it can be accurately embedded in the arc keyway 6 of the prismatic transmission shaft 2. Under the working conditions of frequent start and stop, high-speed operation and complex external forces of the industrial robot, the cooperation between the positioning threaded hole 5 and the positioning ball screw 3 effectively prevents the circumferential and axial relative displacement between the transmission shaft 2 and the rotating part 1, ensures the stability and reliability of torque transmission, and avoids problems such as torque transmission failure or precision reduction caused by relative displacement.

[0043] 4. Process the cylindrical connecting rod into a triangular column shape and a wave bead arc groove

[0044] By processing the cylindrical connecting rod into a prism shape, the multi-faceted contact characteristics of the prism can be used to increase the contact area with the shaft hole, thereby improving the torque transmission capacity. The X, Z, and C three-axis linkage function of the non-circular CNC lathe can accurately control the tool motion trajectory and achieve precise turning of the cylindrical connecting rod. Through multiple tool-pass turning processes, the first tool-pass cutting amount is a1 mm, and each subsequent tool-pass decreases by a2 mm. This can gradually approach the target shape and ensure processing accuracy. Controlling the contour of the prism within 0.01 mm can ensure good matching accuracy with the shaft hole. The glass bead arc groove is processed using the X, Z, and S linkage method to provide a precise embedding position for positioning the ball screw 3, further enhancing the stability of the connection.

[0045] Through precise multiple-pass turning technology and three-axis linkage control, the cylindrical connecting rod is successfully processed into a high-precision triangular column shape. The extremely small contour error ensures the high-precision fit between the triangular column and the shaft hole. The increased contact area makes the torque transmission more uniform, avoids local stress concentration, and improves the overall performance and reliability of the transmission system. The precise processing of the glass bead arc groove provides an accurate embedding position for positioning the wave ball screw 3, further enhancing the stability of the connection, ensuring that the torque can be transmitted stably and efficiently during the torque transmission process of the industrial robot joint motor, reducing transmission failures caused by insufficient matching accuracy.

[0046] 5. Assemble the mitre drive shaft 2 and the rotating part 1

[0047] Insert the processed mitre drive shaft 2 into the mitre shaft hole 4 of the rotating part 1. This process utilizes the dimensional accuracy guaranteed by the previous high-precision processing, so that the two can fit tightly. Then, screw the positioning ball screw 3 through the positioning threaded hole 5, so that its end is embedded in the arc keyway 6 of the mitre drive shaft 2.

[0048] This assembly method is simple and efficient, thanks to the precise processing dimensions of each component. The precise matching of the positioning ball screw 3 with the arc keyway 6 and the positioning threaded hole 5 not only plays a reliable positioning role, but also effectively prevents the circumferential and axial movement of the drive shaft 2 in the shaft hole 4. During the operation of the robot joint motor, this tight and stable connection method can reliably transmit large torque, ensure the precise motion control of the robot joint, and meet the robot's needs for high-precision motion control. Whether in the task scenario of rapid movement or high-precision positioning, it can ensure the stable operation of the robot, reduce motion errors, and improve work efficiency and quality.

[0049] 6. Summary

[0050] It can be clearly seen from the embodiments applied to torque transmission of robot joint motors that this high-torque 3-prism mechanical transmission connection method exhibits significant advantages in many aspects.

[0051] Reliable connection and high transmission torque: From the careful selection of materials and processes in the component preparation stage, to the strict precision control of each processing link, to the anti-loosening design of the positioning threaded holes and positioning ball screws, each link is closely coordinated. This synergy makes the connection extremely reliable and can stably withstand torques of up to 200N·m or even greater, fully meeting the high-torque transmission requirements of industrial robot joint motors under complex working conditions. Compared with traditional connection methods, the torque carrying capacity is greatly improved several times, which effectively ensures the stable operation of industrial robots under harsh working conditions such as heavy loads and high speeds, reduces the risk of failures caused by unreliable connections, and improves the continuity and stability of industrial production.

[0052] High connection accuracy, no backlash: high-precision processing of the entire process from shaft hole, triangular column to threaded hole and arc keyway, especially the contour of the triangular column is controlled at 0.01mm, ensuring the precise fit between components. This high-precision fit effectively avoids the generation of backlash and realizes the precise transmission of torque. When the robot performs various tasks, it can ensure the precise position and posture control of the end effector, improve product quality and production efficiency, reduce scrap rate, and enhance the economic benefits and market competitiveness of the enterprise.

[0053] Compact structure, plug and play: The overall structural design is compact and reasonable, and the connection between components is simple and efficient. After processing, it can be directly assembled, plug and play, convenient and fast. This design not only facilitates the on-site assembly of the robot, reduces assembly time and labor costs, but also effectively reduces the assembly errors that may be caused by complex installation processes, and improves production and maintenance efficiency. In the daily maintenance and fault repair of the robot, damaged parts can be quickly replaced, downtime can be shortened, equipment utilization can be improved, and the operating costs of the enterprise can be reduced.

[0054] Wide range of applications: This method not only performs well in the torque transmission of industrial robot joint motors, but based on its principles and advantages, it can also be widely expanded to other types of machinery that require large torque and stable transmission. For example, in the power transmission of automated production lines, it can ensure stable operation of equipment and improve production efficiency; in the transmission systems of some special machinery, it can also meet the needs of special working conditions with its large torque carrying capacity and high precision. Moreover, the design concept of this method can be extended to the transmission connection of triangular prisms, ellipses or more prisms, showing extremely broad application prospects and promotion value, providing innovative solutions for power transmission in different industrial fields, and promoting the diversified development of industrial machinery transmission technology.

[0055] Solving traditional problems: This invention realizes one-piece forming of connecting rod by optimizing processing technology, which effectively solves the problems that traditional key connection may cause deformation of key and keyway after repeated use and is difficult to disassemble and repair. The contact surface of the mitre column conduction is an integral contact, which greatly increases the torque transmission capacity compared with the traditional connection method, and is especially suitable for mechanical transmission at large torque connections. This innovative design provides a new solution for power transmission in the industrial field that is efficient, reliable and durable, and promotes the advancement of industrial mechanical power technology.

Claims

1. A high torque 3-prism mechanical transmission connection method, characterized in that: The following steps are involved: S1: preparing a rotating member (1) and a cylindrical connecting rod; S2: Processing the triangular prism shaft hole (4) of the rotating part (1): Fix the rotating part (1) on a high-precision CNC machine tool, set the milling speed to n1 rpm and the feed rate to f1 mm / rev; S3: After the axial hole (4) of the prism is processed, the rotating part (1) is re-clamped on the drilling machine, and at the top of the axial hole (4) of the prism, the drill speed is set to n2 rpm and the feed rate is f2 mm / rev to process the positioning threaded hole (5). The depth error of the positioning threaded hole is controlled within ±0.2 mm. S4: Place the cylindrical connecting rod on a non-circular CNC lathe. When processing it into a triangular prism shape, the main shaft is also used to drive the cylindrical connecting rod to rotate. At the same time, the radial feed of the tool is coordinated with the axial feed. Through multiple tool-pass turning processes, the first tool-pass cutting amount is a1 mm, and each subsequent tool-pass decreases by a2 mm. The lathe X, Z, and C three-axis linkage method is used to process it into a triangular prism shape, and the contour of the triangular prism is controlled within 0.01 mm; at the same time, the X, Z, and S linkage method is used to process the wave bead arc groove; S5: Insert the processed and coated mitre column drive shaft (2) into the mitre column shaft hole (4) of the rotating part (1), and then screw the positioning ball screw (3) through the positioning threaded hole (5) so that its end is embedded in the arc keyway (6) of the mitre column drive shaft (2).

2. A high torque 3-prism mechanical transmission connection method as claimed in claim 1, characterized in that: In S2, the spindle drives the rotating part (1) to rotate at a stable speed of n1 rpm, and the tool gradually cuts in along the radial direction according to the designed inner diameter of the shaft hole, while moving axially to complete the milling of the entire shaft hole; according to the accuracy requirements of the inner diameter of the shaft hole being controlled at ±0.01mm and the surface roughness Ra≤0.8μm, the milling function is used to machine the shaft hole (4) of the triangular prism.

3. A high torque 3-prism mechanical transmission connection method as claimed in claim 1, characterized in that: Suitable for heavy-load machinery, high-vibration machinery and other types of machinery that require large torque and stable transmission.

4. A high torque 3-prism mechanical transmission connection method as claimed in claim 1, characterized in that: It is suitable for torque transmission in compact structures and small spaces, including but not limited to power transmission of robot joint motors.

5. A high torque 3-prism mechanical transmission connection method as claimed in claim 1, characterized in that: Suitable for high precision and no hysteresis.

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