Pressing and welding integrated machine for transmission shaft assembly and working method thereof

Abstract

This invention discloses a press-fitting and welding integrated machine for a drive shaft assembly, comprising a support frame, a main shaft, a main shaft motor, a first crossbar, and a second crossbar mounted on the support frame; a clamping and positioning mechanism is disposed on the main shaft for clamping the universal joint assembly and the intermediate spline shaft assembly of the drive shaft sub-shaft and adjusting their relative positions; an assembly composite processing mechanism includes a press-fitting component, a welding component, and a straightening component. The press-fitting component presses the clamped universal joint assembly and the intermediate spline shaft assembly; the straightening component detects the radial runout of the press-fitted drive shaft sub-shaft; the welding component welds the press-fitted drive shaft sub-shaft; and a transfer component transfers the welded drive shaft sub-shaft to the next process; a control component controls each component to work according to a preset procedure. This press-fitting and welding integrated machine enables continuous operation of press-fitting, straightening, and welding of the drive shaft sub-shaft on the same machine, eliminating the time consumption of transfer between processes and secondary clamping errors.

Description

Technical Field

[0001] This invention relates to the field of transmission shaft processing technology, and in particular to a press-fitting and welding integrated machine for transmission shaft assemblies and its working method. Background Technology

[0002] The driveshaft assembly is a core component of the automotive transmission system, responsible for transmitting power from the engine to the drive axle to propel the vehicle. A driveshaft assembly typically consists of multiple components, including a universal joint assembly and a center spline shaft assembly, assembled through press fitting and welding to form the driveshaft sub-shaft, which then proceeds to the final assembly process. The press fitting process ensures interference fit between components, guaranteeing a tight connection and torque transmission capability. The welding process reinforces the press-fitted joints, ensuring structural reliability and fatigue life of the assembly under high-speed rotation and alternating load conditions.

[0003] In existing technologies, the press-fitting and welding processes of drive shaft assemblies are typically configured as two independent production stages, completed separately by dedicated press-fitting and welding equipment. Because press-fitting and welding are performed on two separate machines, the assembly requires unloading, transfer, and re-clamping between processes. This transfer process is time-consuming, significantly increasing the production cycle time per unit and hindering overall production efficiency and capacity improvement. During the transfer and re-clamping process, the drive shaft assembly inevitably faces the risk of loss of positioning accuracy due to impacts, vibrations, or clamping deviations. The coaxiality and positional accuracy established during press-fitting are difficult to fully replicate after re-clamping, directly affecting the weld quality and dynamic balance performance of the final product. The need for separate press-fitting and welding equipment for these two independent processes not only results in large equipment purchase investments and a large floor space requirement, but also necessitates independent maintenance and operation personnel for each set of equipment. This leads to low equipment utilization and workshop space utilization, resulting in high overall manufacturing costs.

[0004] To address the aforementioned problems, this invention provides a press-fitting and welding integrated machine for a drive shaft assembly and its operating method. This equipment enables continuous operations of press-fitting, straightening, and welding of the drive shaft sub-shafts sequentially, eliminating time-consuming transfers between processes and secondary clamping errors, thereby improving production efficiency and product quality consistency. Summary of the Invention

[0005] In view of the problems existing in the press-fitting and welding of the above-mentioned drive shaft assemblies, the present invention is proposed.

[0006] Therefore, the purpose of this invention is to provide a press-fitting and welding integrated machine for a drive shaft assembly and its control method. The purpose is to realize the continuous operation of press-fitting, straightening and welding of the drive shaft sub-shaft on the same machine, so as to eliminate the time consumption of transfer between processes and the secondary clamping error, and improve production efficiency and product quality consistency.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: including a support frame, wherein the support frame is provided with a main shaft, a main shaft motor, a first crossbar and a second crossbar.

[0008] A clamping and positioning mechanism, which is mounted on the main shaft, is used to clamp the universal joint assembly and the intermediate spline shaft assembly of the drive shaft sub-shaft and adjust their relative positions.

[0009] The assembly composite processing mechanism includes a pressing assembly, a welding assembly, and a straightening assembly; the pressing assembly is fixedly connected to the clamping and positioning mechanism and is used to press the clamped universal joint assembly and the intermediate spline shaft assembly; the straightening assembly is disposed on the first crossbar and is used to detect the radial runout of the press-fitted drive shaft sub-shaft; the welding assembly is disposed on the first crossbar and the second crossbar and is used to weld the press-fitted drive shaft sub-shaft.

[0010] A transfer assembly, which is mounted on the support frame, is used to transfer the welded drive shaft sub-shaft to the next process.

[0011] A control component is disposed on the support frame. The control component is electrically connected to the clamping and positioning mechanism, the assembly composite processing mechanism and the transfer component, and is used to control each component to work according to a preset procedure.

[0012] In a preferred embodiment of the press-fitting and welding integrated machine of the present invention, the clamping and positioning mechanism includes a first clamping component and a second clamping component, wherein the first clamping component and the second clamping component are respectively provided with clamping jaws; the first clamping component is fixedly connected to one end of the main shaft for clamping the universal joint assembly; the second clamping component is slidably connected to the main shaft for clamping the intermediate spline shaft assembly, and the second clamping component is driven to slide along the main shaft by the control component.

[0013] In a preferred embodiment of the press-fitting and welding integrated machine of the present invention, the press-fitting component includes a hydraulic station, a tailstock, and a tailstock cylinder; the hydraulic station is mounted on the support frame, the tailstock is fixedly connected to the tailstock cylinder, the piston rod of the tailstock cylinder is connected to the second clamping component, and the hydraulic station drives the tailstock cylinder to apply pressure to the second clamping component, so that the universal joint assembly and the intermediate spline shaft assembly can be assembled together.

[0014] As a preferred embodiment of the press-fitting and welding integrated machine of the present invention, the welding assembly includes two welding guns, which are respectively disposed on the first crossbar and the second crossbar, for simultaneously welding both sides of the transmission shaft sub-shaft.

[0015] In a preferred embodiment of the press-fit welding integrated machine of the present invention, the welding assembly further includes a welding fume curtain, which is disposed on the support frame and the opening or closing of the welding fume curtain is controlled by the control assembly.

[0016] In a preferred embodiment of the press-fitting and welding integrated machine of the present invention, after the transmission shaft sub-shaft is press-fitted, the main spindle motor drives the main spindle to rotate, and the radial runout of the transmission shaft sub-shaft is detected by the straightening component; when the radial runout of the transmission shaft sub-shaft is detected to be ≥0.3mm, the transmission shaft sub-shaft is straightened; when the radial runout is ≤0.3mm, the press-fitting is deemed qualified, and a welding permission signal is sent to the control component.

[0017] As a preferred embodiment of the press-fitting and welding integrated machine of the present invention, the supporting frame further includes a machine tool, a first column, a second column, support legs, and a protective cover; the first column and the second column are disposed on the machine tool, one end of the spindle is connected to the first column, and the other end is connected to the second column; the support legs are disposed below the machine tool, and the protective cover is disposed above the machine tool; the first crossbar and the second crossbar are respectively connected between the first column and the second column.

[0018] In a preferred embodiment of the press-fitting and welding integrated machine of the present invention, the transfer component is configured as a pneumatic three-axis robotic arm, which automatically transfers the transmission shaft sub-shaft that has completed press-fitting and welding to the conveyor belt for the next process.

[0019] As a preferred embodiment of the press-fitting and welding integrated machine of the present invention, the control component includes a PLC controller, a sensor and a touch screen. The sensor is used to monitor the press-fitting force, welding current, welding voltage and spindle speed in real time. When the monitored parameters exceed the preset threshold, the control component performs a fault alarm or automatically stops the machine.

[0020] A method for using a press-fitting and welding machine for a drive shaft assembly, employing the aforementioned press-fitting and welding machine for a drive shaft assembly, is characterized by comprising the following steps: S1: The universal joint assembly and the intermediate spline shaft assembly of the drive shaft sub-shaft are clamped by the clamping and positioning mechanism respectively, and the relative positions of the two are adjusted to make them contact each other; S2: Press-fit the universal joint assembly and the intermediate spline shaft assembly using a press-fit assembly; S3: The radial runout of the transmission shaft sub-shaft after pressing is detected by the straightening component. If the radial runout is ≥0.3mm, straightening is performed until it is qualified. S4: The welding torch and welding fume curtain are moved to the welding station by the control component. The welding component automatically welds the qualified transmission shaft sub-shaft. During the welding process, the control component counts the welding. Welding stops when the preset welding length or welding circle number is reached. Then the welding torch and welding fume curtain are controlled to reset. S5: The welded drive shaft sub-shaft is transferred to the next process using a transfer assembly.

[0021] The beneficial effects of this invention are as follows: By integrating the pressing assembly, straightening assembly, and welding assembly onto the same support frame, and coordinating with the one-time clamping and positioning mechanism and the fully automated collaborative control of the control assembly, the transmission shaft sub-shaft can sequentially and continuously complete the pressing, straightening, and welding operations on the same equipment. This fundamentally eliminates the time spent on inter-process transfers and secondary clamping errors required by traditional separate equipment, significantly shortening the production cycle time of a single product and improving production efficiency. Simultaneously, the closed-loop quality control mechanism, which monitors the radial runout after pressing in real time and allows welding to begin only after it passes inspection, effectively ensures the precision state before welding, avoiding welding quality defects caused by transfer bumps or secondary clamping positioning deviations, and significantly improving the dynamic balance performance and quality consistency of the product. The dual-welding-gun synchronous welding structure further shortens the welding time, while the intelligent control system's real-time monitoring and early warning functions for pressing force, welding parameters, and spindle speed significantly improve the reliability and automation level of the equipment. The follow-up sealing design of the welding fume curtain also effectively improves the working environment. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 A schematic diagram of the overall structure of the press-fitting and welding integrated machine of this embodiment is shown; Figure 2 This diagram illustrates the overall flow of the press-fitting and welding integrated machine operation method according to this embodiment. Figure 3 A flowchart illustrating step S3 of the press-fitting and welding integrated machine operation method of this embodiment is shown.

[0024] Reference numerals: 1. Support frame; 11. Machine tool; 12. First column; 13. Second column; 14. Support leg; 15. Protective cover; 2. Spindle; 3. Spindle motor; 4. First crossbar; 5. Second crossbar; 6. Clamping and positioning mechanism; 61. First clamping assembly; 62. Second clamping assembly; 7. Assembly composite machining mechanism; 71. Pressing assembly; 711. Hydraulic station; 712. Tailstock; 713. Tailstock cylinder; 713a. Piston rod; 72. Welding assembly; 721. Welding torch; 722. Welding fume curtain; 73. Straightening assembly; 8. Transfer assembly; 9. Control assembly. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0026] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0027] Example 1, referring to Figure 1 The first embodiment of the present invention provides a press-fitting and welding integrated machine for a drive shaft assembly. This device includes a support frame 1, on which a main shaft 2, a main shaft 2 motor, a first crossbar 4, and a second crossbar 5 are provided.

[0028] The clamping and positioning mechanism 6 is mounted on the main shaft 2 and is used to clamp the universal joint assembly and the intermediate spline shaft assembly of the drive shaft sub-shaft and adjust their relative positions.

[0029] The assembly composite processing mechanism 7 includes a pressing assembly 71, a welding assembly 72, and a straightening assembly 73. The pressing assembly 71 is fixedly connected to the clamping and positioning mechanism 6 and is used to press the clamped universal joint assembly and intermediate spline shaft assembly. The straightening assembly 73 is set on the first crossbar 4 and is used to detect the radial runout of the press-fitted drive shaft sub-shaft. The welding assembly 72 is set on the first crossbar 4 and the second crossbar 5 and is used to weld the press-fitted drive shaft sub-shaft.

[0030] The transfer assembly 8, which is mounted on the support frame 1, is used to transfer the welded drive shaft sub-shaft to the next process.

[0031] The control component 9 is mounted on the support frame 1. The control component 9 is electrically connected to the clamping and positioning mechanism 6, the assembly composite processing mechanism 7, and the transfer component 8, and is used to control each component to work according to the preset process.

[0032] The main spindle 2 is horizontally positioned in the middle of the support frame 1, serving to support and position the various components of the drive shaft sub-shaft to be processed. The output end of the motor of the main spindle 2 is electrically connected to the main spindle 2 housing, driving the main spindle 2 to rotate around its axis via the main spindle 2 housing. The first crossbar 4 and the second crossbar 5 are respectively arranged parallel above the main spindle 2, used to install the various functional components in the assembly composite machining mechanism 7. The clamping and positioning mechanism 6 is set on the main spindle 2 to clamp the universal joint assembly and the intermediate spline shaft assembly that make up the drive shaft sub-shaft, and adjusts their relative positions along the axial direction of the main spindle 2 according to control commands, so that their ends contact each other in preparation for press fitting. The press fitting assembly 71 is connected to the clamping and positioning mechanism 6, and applies pressure to the clamping and positioning mechanism 6 to press the universal joint assembly and the intermediate spline shaft assembly with an interference fit. After press fitting is completed, the radial runout of the drive shaft sub-shaft is detected by the straightening assembly 73. After the straightening assembly 73 determines that the press fitting of the drive shaft sub-shaft is qualified, the welding assembly 72 welds and reinforces the press-fitted part of the drive shaft sub-shaft. The transfer assembly 8 removes the completed press-fit and welded drive shaft sub-shaft from the equipment and transfers it to the next process. The control assembly 9 is electrically connected to the clamping and positioning mechanism 6, the assembly composite processing mechanism 7, and the transfer assembly 8 via electrical wiring. The control assembly 9 has pre-set execution programs for each process, used to control the start, operation, stop, and coordination of each component according to the preset process sequence, achieving fully automated operation. By integrating the three core processes of press-fitting, straightening, and welding onto the same support frame 1, the entire process of press-fitting and welding the drive shaft sub-shaft can be completed continuously without intermediate unloading and transfer, eliminating the time spent on inter-process transfers, reducing equipment footprint, and lowering the labor intensity of operators.

[0033] Furthermore, the clamping and positioning mechanism 6 includes a first clamping component 61 and a second clamping component 62, each of which is provided with clamping jaws; the first clamping component 61 is fixedly connected to one end of the main shaft 2 for clamping the universal joint assembly; the second clamping component 62 is slidably connected to the main shaft 2 for clamping the intermediate spline shaft assembly, and the second clamping component 62 is driven to slide along the main shaft 2 by the control component 9.

[0034] The clamping jaws are preferably pneumatic or hydraulic, with two or three jaws evenly distributed circumferentially for centering and clamping the workpiece. The first clamping assembly 61 is fixedly connected to the end of the spindle 2 furthest from the pressing assembly 71. Its clamping jaws are used to clamp the universal joint assembly, allowing it to rotate synchronously with the spindle 2 while remaining axially fixed. The second clamping assembly 62 is slidably connected to the spindle 2 and can reciprocate along the axial direction of the spindle 2 under the drive of the control assembly 9. Its clamping jaws are used to clamp the intermediate spline shaft assembly. The sliding drive of the second clamping assembly 62 is controlled by the control assembly 9, which drives the second clamping assembly 62 to move along the spindle 2, thereby adjusting the distance between the first and second clamping assemblies 61 and 62, allowing the universal joint assembly and the intermediate spline shaft assembly to be placed on the spindle 2, preparing for the subsequent pressing process. During operation, the control component 9 first drives the second clamping component 62 to move to a suitable position, and the clamping jaws of the first clamping component 61 clamp and fix the universal joint assembly to one end of the main shaft 2. Then, it drives the clamping jaws of the second clamping component 62 to close, clamping the intermediate spline shaft assembly. This structure, through the sliding fit between the second clamping component 62 and the main shaft 2, achieves flexible adaptation of drive shaft sub-shafts of different lengths, expanding the processing range of the equipment. Simultaneously, it ensures the coaxiality accuracy between the two components before press-fitting, providing a fundamental guarantee for the subsequent press-fitting quality.

[0035] Furthermore, the support frame 1 also includes a machine tool 11, a first column 12, a second column 13, a support leg 14, and a protective cover 15; the first column 12 and the second column 13 are mounted on the machine tool 11, one end of the spindle 2 is connected to the first column 12, and the other end is connected to the second column 13; the support leg 14 is located below the machine tool 11, and the protective cover 15 is located above the machine tool 11; the first crossbar 4 and the second crossbar 5 are respectively connected between the first column 12 and the second column 13.

[0036] The machine tool 11 is a horizontally arranged plate-shaped or frame-like structure, serving as the basic platform for the entire equipment. The first column 12 and the second column 13 are both vertically fixed to the upper surface of the machine tool 11 and spaced apart along its length. The spindle 2 is horizontally positioned between the two columns, with one end rotatably connected to the first column 12 via a bearing seat and the other end rotatably connected to the second column 13 via a bearing seat. The spindle 2 motor is fixedly mounted on the outer surface of the first column 12 and connected to the spindle 2 via a coupling. The first crossbar 4 and the second crossbar 5 are both horizontally arranged rod-shaped structures, spaced apart along the axial direction of the spindle 2. One end of each crossbar connects to the first column 12, and the other end connects to the second column 13, both located above the spindle 2. The support legs 14 are multiple vertical support feet fixed to the bottom of the machine tool 11. The protective cover 15 is a transparent shell structure covering the machine tool 11, enclosing all processing mechanisms within it. In this embodiment, the machine tool 11, column and crossbar form a rigid and stable equipment foundation frame to ensure the relative position accuracy of each component during press-fitting and welding. The protective cover 15 plays a safety isolation role during operation.

[0037] Example 2, refer to Figure 1 This is the second embodiment of the present invention, which differs from the first embodiment in that: the press assembly 71 includes a hydraulic station 711, a tailstock 712, and a tailstock 712 cylinder; the hydraulic station 711 is mounted on the support frame 1, the tailstock 712 is fixedly connected to the tailstock 712 cylinder, the piston rod 713a of the tailstock 712 cylinder is connected to the second clamping assembly 62, and the hydraulic station 711 drives the tailstock 712 cylinder to apply pressure to the second clamping assembly 62, so that the universal joint assembly and the intermediate spline shaft assembly can be assembled together.

[0038] The hydraulic station 711 is fixedly mounted on the support frame 1 and integrates hydraulic components such as a hydraulic pump, oil tank, relief valve, directional control valve, and pressure regulating valve to provide high-pressure hydraulic oil with preset pressure and flow rate. The tailstock 712 is fixedly installed at one end of the support frame 1, its position maintained along the axial direction of the main shaft 2, serving as the bearing base for the press-fit reaction force. The tailstock 712 cylinder is fixedly mounted on the tailstock 712, with the piston rod 713a extending parallel to the axial direction of the main shaft 2, and its end fixedly connected to the second clamping assembly 62. The hydraulic station 711 is connected to the rod-side and rodless-side chambers of the tailstock 712 cylinder via hydraulic lines. The control assembly 9 precisely controls the extension and retraction of the piston rod 713a of the tailstock 712 cylinder by controlling the on / off and reversal of the directional control valve. During operation, after the clamping and positioning mechanism 6 completes the loading and positioning, the control component 9 sends a pressing command to the hydraulic station 711. The hydraulic station 711 supplies high-pressure hydraulic oil to the rodless chamber of the tailstock 712 cylinder, driving the piston rod 713a of the tailstock 712 cylinder to extend. The piston rod 713a pushes the second clamping component 62, along with the intermediate spline shaft assembly it clamps, to slide along the main shaft 2 towards the first clamping component 61, so that the end of the intermediate spline shaft assembly is gradually pressed into the mating hole of the universal joint assembly, achieving an interference fit assembly. When the pressing is in place, the control component 9 controls the direction control valve to switch, and the piston rod 713a of the tailstock 712 cylinder drives the second clamping component 62 to slightly retract and unload, completing the pressing process. The piston rod 713a of the tailstock 712 cylinder directly drives the second clamping assembly 62 to slide along the main shaft 2, combining the application of the pressing force with the sliding action of the second clamping assembly 62 into one, eliminating intermediate force transmission components and making the structure more compact; at the same time, the pressing force is directly transmitted to the intermediate spline shaft assembly through the clamping jaws of the second clamping assembly 62, with a short force transmission path and high coaxiality, effectively ensuring uniform force on the workpiece during the pressing process and improving pressing accuracy and consistency.

[0039] Furthermore, the welding assembly 72 includes two welding torches 721, which are respectively mounted on the first crossbar 4 and the second crossbar 5, for simultaneously welding both sides of the drive shaft sub-shaft.

[0040] Two welding torches 721 are respectively mounted on the first crossbar 4 and the second crossbar 5, and are positioned opposite each other along the axial direction of the main shaft 2. Each welding torch 721 is slidably mounted on the corresponding crossbar via a welding torch 721 clamping seat and is equipped with a lifting drive mechanism. The welding torch 721 can move along the crossbar direction to adjust its radial and axial positions relative to the axis of the main shaft 2. The welding parameters of the two welding torches 721 are independently controlled by the control component 9. After the straightening component 73 determines that the pressing is qualified, the control component 9 drives the two welding torches 721 to descend synchronously to both sides of the pressing part of the transmission shaft sub-shaft and simultaneously ignite the arc for welding. The two welding torches 721 move synchronously along the axial direction to perform symmetrical welding. During the welding process, the motor of the main shaft 2 drives the main shaft 2 to rotate the transmission shaft sub-shaft at a uniform speed, so that the welding torches 721 complete a full circle of weld in the circumferential direction. After the welding is completed, the two welding torches 721 rise synchronously to reset. This embodiment uses two welding torches 721 to simultaneously and symmetrically weld on both sides, which reduces the welding time by half and greatly improves the welding efficiency. At the same time, the symmetrical heat input on both sides effectively offsets the welding deformation, improving the weld quality and product precision.

[0041] Furthermore, the welding assembly 72 also includes a welding fume curtain 722, which is mounted on the support frame 1 and is controlled to unfold or retract by the control assembly 9.

[0042] The welding fume curtain 722 includes a curtain fabric, a roller, a curtain motor, and guide rails. The roller is rotatably mounted on the upper part of the support frame 1. One end of the curtain fabric is wound around the roller, while the other end is free. The guide rails are vertically arranged on both sides of the welding station. The two edges of the free end of the curtain fabric are slidably embedded in the guide rails. The curtain motor is controlled by the control component 9 to rotate forward and backward to drive the curtain fabric to unfold or retract. The working process of this embodiment is as follows: when the welding torch 721 moves to the welding station, the control component 9 simultaneously drives the curtain motor to rotate forward, the roller releases the curtain fabric, and the curtain fabric unfolds under its own weight and guided by the guide rails, forming a protective barrier around the welding area. After welding is completed, the control component 9 drives the curtain motor to rotate backward, the roller rewinds the curtain fabric to its original position, facilitating loading and unloading operations. This embodiment, through the automatic unfolding and retraction of the welding fume curtain 722, provides effective protection during welding, improves the working environment, and its automated control does not add extra operating steps or affect production efficiency.

[0043] Furthermore, after the transmission shaft sub-shaft is press-fitted, the main spindle 2 motor drives the main spindle 2 to rotate, and the radial runout of the transmission shaft sub-shaft is detected by the straightening component 73; when the radial runout of the transmission shaft sub-shaft is detected to be ≥0.3mm, the transmission shaft sub-shaft is straightened; when the radial runout is ≤0.3mm, the press-fitting is deemed qualified, and a welding permission signal is sent to the control component 9.

[0044] The straightening assembly 73 is fixedly mounted on the first crossbar 4, and specifically includes a radial runout detection sensor and a straightening actuator. The radial runout detection sensor is preferably a laser displacement sensor or an eddy current displacement sensor, which measures the radial displacement change of the drive shaft sub-shaft surface in real time in a non-contact manner, with a measurement accuracy of ±0.01mm. The sensor output signal is transmitted to the control assembly 9 in real time. The straightening actuator includes a straightening pressure head and a straightening cylinder. The straightening cylinder is fixed on the first crossbar 4, and its piston rod 713a extends vertically downwards and is fixedly connected to the straightening pressure head at its end. The lower end face of the straightening pressure head has an arc-shaped groove matching the outer diameter of the drive shaft sub-shaft. After pressing, the spindle 2 motor drives the spindle 2 to rotate uniformly at a preset speed. The radial runout detection sensor continuously measures the radial runout at a specified detection position on the drive shaft sub-shaft and transmits the signal to the control assembly 9. The control assembly 9 calculates the maximum radial runout during one rotation and compares it with a preset threshold of 0.3mm. Let the coaxiality machining error of the universal joint assembly be δ1, the coaxiality machining error of the intermediate spline shaft assembly be δ2, and the maximum eccentricity between the two reference center lines after press-fitting be e. Then, the radial runout of the transmission shaft sub-shaft after press-fitting satisfies Δ=δ1+δ2+2e. Testing shows that under conventional precision machining conditions, δ1 and δ2 are both controlled within 0.05mm. The high-precision clamping and positioning mechanism 6 of this equipment can stably control the press-fitting eccentricity e within 0.10mm. Substituting into the formula, we get Δ=0.05+0.05+2×0.10=0.30mm. Therefore, the straightening qualification threshold is set to 0.3mm.

[0045] If the radial runout is ≤0.3mm, the press-fitting is determined to be qualified, and the control component 9 automatically generates a "welding permission signal" and sends it to the enable control terminal of the welding component 72. The welding component 72 can only start welding after receiving this signal. This "welding permission signal" serves as a hard interlock precondition for welding start, and the welding torch 721 cannot strike an arc when the signal is not received. If the radial runout is ≥0.3mm, the press-fitting is determined to be unqualified, and the control component 9 does not send the welding permission signal, but starts the straightening procedure. The straightening procedure adopts a multi-point repeated iterative straightening process of "detection-positioning-reverse compensation overpressure-springback monitoring": first, the control component 9 calculates the rotation angle of the main shaft 2 corresponding to the highest point of the runout according to the data collected by the radial runout detection sensor at different rotation angles, drives the main shaft 2 to precisely rotate this high point to the upward position, ensuring that this high point is directly facing the straightening pressing head; then the control component 9 drives the piston rod 713a of the straightening oil cylinder to extend, the straightening pressing head presses down on the surface of the runout high point, adopting the principle of "reverse bending compensation" — the pressing head applies a concentrated pressure greater than the yield strength of the material but less than the tensile strength at the high point, so that the shaft tube produces reverse plastic concave deformation at the high point to offset the original radial runout. At the same time, in order to avoid insufficient correction caused by elastic springback of the material after straightening, the control component 9 adopts the "overpressure amount control" strategy, that is, according to the current out-of-tolerance amount, material hardness and wall thickness parameters, a pressing depth greater than the theoretical correction amount is preset, and the straightening pressing head holds the pressure for 1 to 2 seconds before releasing the pressure. After the straightening is completed, the main shaft 2 rotates at least one full turn again, the sensor re-detects the radial runout, and compares it with the 0.3mm threshold again. If it is still unqualified, the above iterative process of "detection-positioning-pressing down-springback re-measurement" is repeated until the radial runout converges to ≤0.3mm, and the control component 9 sends a welding permission signal to the welding component 72. In this embodiment, a hard interlock of press-fitting quality to welding authority is formed through the "welding permission signal", which fundamentally eliminates the possibility of unqualified products entering the welding process and ensures the consistency of the final product accuracy. At the same time, the non-contact displacement sensor combined with the closed-loop algorithm of "overpressure amount control + iterative straightening" greatly improves the accuracy and efficiency compared with the traditional manual dial indicator detection and hammering straightening method, and the scientific setting of the 0.3mm threshold ensures the coordinated optimization of quality and efficiency.

[0046] The rest of the structure is the same as that of Embodiment 1.

[0047] Embodiment 3, referring to Figure 1 , which is the third embodiment of the present invention, this embodiment differs from the second embodiment in that: the transfer component 8 is set as a pneumatic three-axis manipulator, which automatically transfers the press-fitted and welded transmission shaft sub-shaft to the conveyor belt to enter the next process through the pneumatic three-axis manipulator.

[0048] The pneumatic three-axis robotic arm is mounted on one side of the support frame 1 and has linear motion degrees of freedom in the X, Y, and Z axes, each driven by a separate cylinder. A pneumatic gripper at the end of the robotic arm is used to hold the transmission shaft sub-shaft after press-fitting and welding. The movement of each axis is precisely controlled by the control component 9 via a group of solenoid valves. The working process of this embodiment is as follows: after welding is completed and the welding torch 721 and welding fume curtain 722 are reset, the control component 9 sends a part-removal command to the pneumatic three-axis robotic arm. The robotic arm then sequentially executes the following sequence: Z-axis descent → pneumatic gripper closes to clamp the transmission shaft sub-shaft → Z-axis ascent → X-axis translation above the conveyor belt → Z-axis descent → pneumatic gripper releases to place the workpiece → Z-axis descent back to its original position, completing the automatic unloading and transfer. This embodiment achieves automatic removal and transfer of the transmission shaft sub-shaft after press-fitting and welding using a pneumatic three-axis robotic arm, replacing manual handling and improving the automated continuous operation capability of the production line.

[0049] Furthermore, the control component 9 includes a PLC controller, sensors, and a touch screen. The sensors are used to monitor the pressing force, welding current, welding voltage, and spindle speed 2 in real time. When the monitored parameters exceed the preset threshold, the control component 9 executes a fault alarm or automatically stops the machine.

[0050] The PLC controller serves as the core of the control system, storing preset control programs and process parameter thresholds. The sensor group includes various types such as pressure sensors, current sensors, voltage sensors, and speed sensors, deployed at key monitoring locations on the equipment: the pressure sensor is installed in the output pipeline of the hydraulic station 711 to monitor the pressing force in real time; the current and voltage sensors are respectively installed in the power supply circuit of the welding assembly 72 to monitor the welding current and welding voltage in real time; and the speed sensor is installed at the motor of spindle 2 or the end of spindle 2 to monitor the spindle speed in real time. The signal output terminals of all the above sensors are connected to the analog input module of the PLC controller, continuously acquiring the actual values ​​of each parameter with a millisecond sampling period. A touch screen is installed on the operation panel of the support frame 1 to display the equipment operating status and real-time monitoring parameters, and to allow operators to set process parameters and thresholds. The PLC controller has preset thresholds for pressing force, welding current, welding voltage, and spindle speed. When the monitoring parameter fed back by any sensor exceeds the corresponding preset threshold range, the PLC controller determines that the equipment is in an abnormal working state and immediately executes a fault alarm or automatic shutdown. This embodiment utilizes a multi-sensor fusion intelligent monitoring system to achieve comprehensive real-time monitoring of the pressing, welding, and rotation processes, ensuring the long-term reliability and stability of the equipment.

[0051] The remaining structure is the same as that in Example 2.

[0052] A working method for a press-fitting and welding machine for a drive shaft assembly, referring to... Figure 2 , Figure 3 The press-fitting and welding machine applied to the aforementioned drive shaft assembly includes steps S1-S5.

[0053] S1: The universal joint assembly and the intermediate spline shaft assembly of the drive shaft sub-shaft are clamped by the clamping and positioning mechanism 6, and their relative positions are adjusted to make them contact each other. The control component 9 drives the second clamping component 62 to move to the appropriate position, and the clamping jaws of the first clamping component 61 close, clamping and fixing the universal joint assembly to one end of the main shaft 2; at the same time, the control component 9 drives the clamping jaws of the second clamping component 62 to close, clamping and fixing the intermediate spline shaft assembly, thus completing the loading and positioning.

[0054] S2: The universal joint assembly and the intermediate spline shaft assembly are press-fitted using the press-fitting assembly 71. The control assembly 9 starts the hydraulic station 711, supplies oil to the tailstock 712 cylinder, drives the piston rod 713a of the tailstock 712 cylinder to extend, and the piston rod 713a pushes the second clamping assembly 62 to slide along the main shaft 2, pressing the intermediate spline shaft assembly into the mating hole of the universal joint assembly, completing the interference fit press-fit.

[0055] S3: The radial runout of the transmission shaft sub-shaft after press-fitting is detected by the straightening component 73. If the radial runout is ≥0.3mm, straightening is performed until it passes the test. The control component 9 starts the spindle 2 motor to drive the spindle 2 to rotate at a constant speed. The radial runout detection sensor of the straightening component 73 detects the radial runout of the rotating transmission shaft sub-shaft in real time. The control component 9 compares the detected maximum radial runout with the preset threshold of 0.3mm: if ≤0.3mm, the press-fitting is deemed qualified and proceeds to the next step; if ≥0.3mm, the press-fitting is deemed unqualified, and the control component 9 starts the straightening program. Based on the sensor data, the rotation angle corresponding to the maximum runout point is calculated, and the spindle 2 is driven to rotate the maximum point to the upward position. The piston rod 713a of the straightening cylinder is extended and the straightening pressure head is pressed down to perform straightening. The test is repeated after straightening until it passes the test.

[0056] S4: The control component 9 moves the welding torch 721 and welding fume curtain 722 to the welding station. The welding component 72 automatically welds the press-fitted transmission shaft sub-shaft. During the welding process, the control component 9 counts the welding. Welding stops when the preset welding length or welding revolutions are reached, and then the control component 9 resets the welding torch 721 and welding fume curtain 722. After the control component 9 confirms that the alignment is qualified, it sends a movement command to the drive mechanism of the welding torch 721 and welding fume curtain 722. The welding torch 721 descends from the standby position to the welding station, and the welding fume curtain 722 simultaneously unfolds and descends to form protection. After reaching the position, the welding torch 721 ignites the arc and starts welding. During the welding process, the motor of the main shaft 2 drives the main shaft 2 to rotate at a constant speed. The counter inside the control component 9 counts the welding length or the number of rotations of the main shaft 2 in real time. When the preset welding length or the preset number of welding revolutions are reached, the welding torch 721 extinguishes the arc and stops welding. Then the welding torch 721 and welding fume curtain 722 reset.

[0057] S5: The welded drive shaft sub-shaft is transferred to the next process via transfer component 8. Control component 9 sends a pick-up command to the pneumatic three-axis robotic arm. The robotic arm descends and the grippers close to clamp the drive shaft sub-shaft. Control component 9 then controls the clamping and positioning component to release the drive shaft sub-shaft. Transfer component 8 subsequently rises, moves horizontally to the conveyor belt, descends, and the grippers release to place the drive shaft sub-shaft, transferring the welded drive shaft sub-shaft onto the conveyor belt for the next process. The robotic arm then returns to its original position, completing one work cycle. This method achieves fully automated continuous operation of the drive shaft sub-shaft on the same equipment through a complete process flow. The closed-loop control of the 0.3mm threshold judgment and straightening process in step S3 ensures that only workpieces with qualified pressing accuracy can enter the welding process. The workpiece only needs to be clamped once and does not need to be unloaded and transferred midway, significantly improving production efficiency and product quality.

[0058] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible (e.g., changes in the size, dimensions, structure, shape, and proportions of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in this application). For example, an element shown as integrally formed may be composed of multiple parts or elements, the position of elements may be inverted or otherwise altered, and the nature or number or position of discrete elements may be changed or altered. Therefore, all such modifications are intended to be included within the scope of the invention. The order or sequence of any process or method steps may be changed or rearranged according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and not only structurally equivalent but also equivalent in structure. Other substitutions, modifications, alterations, and omissions may be made in the design, operation, and arrangement of the exemplary embodiments without departing from the scope of the invention. Therefore, the present invention is not limited to the specific embodiments, but extends to various modifications that still fall within the scope of the appended claims.

[0059] Furthermore, to provide a concise description of exemplary embodiments, not all features of actual embodiments (i.e., those features not relevant to the currently considered best mode for carrying out the invention, or those features not relevant to implementing the invention) may be omitted. It should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention and not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A press-fitting and welding integrated machine for a drive shaft assembly, characterized in that, include: A support frame (1) is provided on the support frame (1), which is equipped with a main shaft (2), a main shaft (2) motor, a first crossbar (4) and a second crossbar (5); A clamping and positioning mechanism (6) is provided on the main shaft (2) for clamping the universal joint assembly and the intermediate spline shaft assembly of the transmission shaft sub-shaft and adjusting their relative positions. The assembly composite processing mechanism (7) includes a pressing assembly (71), a welding assembly (72), and a straightening assembly (73); the pressing assembly (71) is fixedly connected to the clamping and positioning mechanism (6) and is used to press the universal joint assembly and the intermediate spline shaft assembly after clamping; the straightening assembly (73) is disposed on the first crossbar (4) and is used to detect the radial runout of the drive shaft sub-shaft after pressing; the welding assembly (72) is disposed on the first crossbar (4) and the second crossbar (5) and is used to weld the press-fitted drive shaft sub-shaft. The transfer assembly (8), which is disposed on the support frame (1), is used to transfer the welded drive shaft sub-shaft to the next process; A control component (9) is disposed on the support frame (1). The control component (9) is electrically connected to the clamping and positioning mechanism (6), the assembly composite processing mechanism (7) and the transfer component (8), and is used to control each component to work according to a preset procedure.

2. The press-fitting and welding integrated machine according to claim 1, characterized in that, The clamping and positioning mechanism (6) includes a first clamping component (61) and a second clamping component (62). The first clamping component (61) and the second clamping component (62) are respectively provided with clamping jaws. The first clamping component (61) is fixedly connected to one end of the main shaft (2) for clamping the universal joint assembly. The second clamping component (62) is slidably connected to the main shaft (2) for clamping the intermediate spline shaft assembly. The second clamping component (62) is driven to slide along the main shaft (2) by the control component (9).

3. The press-fitting and welding integrated machine according to claim 2, characterized in that, The press assembly (71) includes a hydraulic station (711), a tailstock (712), and a tailstock (712) cylinder. The hydraulic station (711) is mounted on the support frame (1). The tailstock (712) is fixedly connected to the tailstock (712) cylinder. The piston rod (713a) of the tailstock (712) cylinder is connected to the second clamping assembly (62). The hydraulic station (711) drives the tailstock (712) cylinder to apply pressure to the second clamping assembly (62), so that the universal joint assembly and the intermediate spline shaft assembly can be assembled together.

4. The press-fitting and welding integrated machine according to claim 1, characterized in that, The welding assembly (72) includes two welding torches (721), which are respectively mounted on the first crossbar (4) and the second crossbar (5) for simultaneously welding both sides of the drive shaft sub-shaft.

5. The press-fitting and welding integrated machine according to claim 4, characterized in that, The welding assembly (72) also includes a welding fume curtain (722), which is mounted on the support frame (1) and is controlled to unfold or retract by the control assembly (9).

6. The press-fitting and welding integrated machine according to claim 1, characterized in that: After the transmission shaft sub-shaft is press-fitted, the main shaft (2) motor drives the main shaft (2) to rotate, and the radial runout of the transmission shaft sub-shaft is detected by the straightening component (73); when the radial runout of the transmission shaft sub-shaft is detected to be ≥0.3mm, the transmission shaft sub-shaft is straightened; when the radial runout is ≤0.3mm, the press-fitting is deemed qualified, and a welding permission signal is sent to the control component (9).

7. The press-fitting and welding integrated machine according to claim 1, characterized in that, The support frame (1) also includes a machine tool (11), a first column (12), a second column (13), a support leg (14), and a protective cover (15); the first column (12) and the second column (13) are mounted on the machine tool (11), one end of the spindle (2) is connected to the first column (12), and the other end is connected to the second column (13); the support leg (14) is located below the machine tool (11), and the protective cover (15) is located above the machine tool (11); the first crossbar (4) and the second crossbar (5) are respectively connected between the first column (12) and the second column (13).

8. The press-fitting and welding integrated machine according to claim 1, characterized in that, The transfer component (8) is configured as a pneumatic three-axis robotic arm, which automatically transfers the transmission shaft sub-shaft that has completed pressing and welding to the conveyor belt for the next process.

9. The press-fitting and welding integrated machine according to claim 1, characterized in that, The control component (9) includes a PLC controller, sensors and a touch screen. The sensors are used to monitor the pressing force, welding current, welding voltage and spindle (2) speed in real time. When the monitored parameters exceed the preset threshold, the control component (9) performs a fault alarm or automatic shutdown.

10. A method for operating a press-fitting and welding machine for a drive shaft assembly, using the press-fitting and welding machine for a drive shaft assembly as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1: The universal joint assembly and the intermediate spline shaft assembly of the transmission shaft sub-shaft are clamped by the clamping and positioning mechanism (6) respectively, and the relative positions of the two are adjusted to make them contact each other; S2: Press-fit the universal joint assembly and the intermediate spline shaft assembly using the press-fit assembly (71); S3: The radial runout of the transmission shaft sub-shaft after pressing is detected by the straightening component (73). If the radial runout is ≥0.3mm, straightening is performed until it is qualified. S4: The welding torch (721) and welding fume curtain (722) are moved to the welding station by the control component (9). The welding component (72) automatically welds the qualified transmission shaft sub-shaft. During the welding process, the control component (9) counts and stops welding when the preset welding length or welding circle number is reached. Then the welding torch (721) and welding fume curtain (722) are reset. S5: The welded drive shaft sub-shaft is transferred to the next process via the transfer assembly (8).

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