Automatic hole drilling method for titanium alloy U-shaped thin-wall cover-shaped structure

Abstract

The present application relates to a kind of titanium alloy U-shaped thin-wall cover structure automatic hole making method, solve the problem of low efficiency, poor consistency of manual hole making.It includes the following steps: step 1: tool design is stepped drill, product is positioned by positioning hole and outer surface positioning;Step 2: design robot assembly auxiliary tool;Step 3: use laser tracker to calibrate datum point on the machined surface of robot assembly auxiliary tool;Step 4: use laser tracker to measure the positioning accuracy and repeatability of robot assembly auxiliary tool;Step 5: get the optimal hole making processing parameter;Step 6: system uses bus type distributed communication structure, realizes the automatic hole making of titanium alloy U-shaped thin-wall cover structure through host computer coordination.This application realizes titanium alloy U-shaped thin-wall cover structure automatic hole making + dimming integrated processing, improves production efficiency and hole making precision, greatly improves product consistency and stability.

Description

Technical Field

[0001] The invention belongs to the technical field of industrial robot application, and particularly relates to an automatic hole-making method for a titanium alloy U-shaped thin-walled cover-shaped structure. Background Art

[0002] With the continuous innovation and development of science and technology, industrial production is gradually transitioning towards automation and intelligence. The penetration rate of industrial robots provides a valuable indicator of the technological level of a country's manufacturing industry. For manufacturing companies, the use of industrial robots can improve production efficiency and precision while significantly reducing labor costs. Currently, industrial robots have been successfully applied across various industries, particularly in automotive production and logistics. However, in aerospace manufacturing, the level of automation and intelligence in manufacturing is relatively low, and industrial robots have not yet been widely adopted. With the rapid development and breakthroughs in aerospace manufacturing, traditional manual assembly is no longer efficient enough to meet the demands of mass production, necessitating the urgent need to replace traditional manual assembly with industrial robots.

[0003] In order to solve the problems of difficult manual countersinking and dimpling of titanium alloy plates, large number of holes with low consistency, low stability of hole quality, high manual operation intensity, low production efficiency and high rework and repair rate during the assembly process of titanium alloy U-shaped thin-walled cover-shaped structure products, research on robot automatic hole making technology is carried out to realize the application of assembly robots in automated and high-precision hole making on the surface of titanium alloy U-shaped thin-walled cover-shaped structure parts, which can reduce manual labor intensity, improve the first-time qualified rate of product assembly, have high product quality consistency and reliability, and improve overall assembly efficiency. Summary of the Invention

[0004] The present invention uses an assembly robot in combination with an automatic hole-making device to fix a titanium alloy U-shaped thin-walled cover-like structure (the workpiece) on a specific workstation. After the robot locates the workpiece through sensors, it controls the rotation of the tool according to the processing procedure to drill a countersunk hole (with a countersink) of a specific size and depth at a specified position on the workpiece.

[0005] To address the low precision and stability of manual hole-making at specific locations on titanium alloy sheet metal surfaces, along with the high operational intensity and limited operational complexity, which is influenced by operator proficiency and individual skills, leading to poor hole consistency, frequent rework, and low efficiency during assembly, a robotic automated hole-making process has been designed. This method enables integrated high-precision hole-making and countersinking on the surfaces of titanium alloy U-shaped, thin-walled, hood-like structures. Hole-making quality and efficiency were verified under different drill feed rates and speeds, resulting in a set of process parameters that achieve optimal hole-making quality and efficiency, significantly improving work efficiency and enhancing product consistency and stability.

[0006] The present invention is achieved by the following technical solutions:

[0007] A method for automatically making holes in a titanium alloy U-shaped thin-walled cover-shaped structure comprises the following steps:

[0008] Step 1: Determine the tool structure design based on the hole position characteristics of the workpiece. The tool is designed as a step drill, and the product is positioned through the positioning hole and the outer surface;

[0009] Step 2: Design the robot assembly auxiliary tooling according to the shape and structural characteristics of the workpiece. The tooling includes left and right supporting columns, a rotating body supported on them, and a driving unit. The driving unit drives the rotating body to rotate.

[0010] The tooling can simultaneously clamp four quadrants of products, completing all hole-making tasks in one clamping. The workstations can be switched by rotation to adapt to the robot's workspace. Once the workstation is rotated into position, a locking device eliminates the backlash of the transmission system to ensure hole-making accuracy. The product is clamped and positioned by the positioning cylindrical boss, side positioning surfaces, bottom positioning surfaces, pressure blocks, and clamps on the tooling. The positioning cylindrical boss cooperates with the product's positioning holes, and the side positioning surfaces, bottom positioning surfaces, and outer surface of the product to achieve positioning. The pressure blocks and clamps clamp the workpiece.

[0011] Step 3: Use a laser tracker to calibrate the reference points on the surface to be processed by the robot assembly auxiliary tooling to determine the spatial position of the hole to be processed in space;

[0012] Step 4: Use a laser tracker to measure the positioning accuracy and repeatability of the robot assembly auxiliary tooling; according to the "General Rules for Machine Tool Inspection Part 2: Determination of Positioning Accuracy and Repeatability of CNC Axis Lines", the tooling positioning accuracy and repeatability are measured by selecting 9 points at intervals of 30° within the measurable range of tooling rotation, with a positive and negative overtravel of 3° each, to ensure that its accuracy meets the hole-making accuracy design requirements.

[0013] Step 5: Set different machining parameters (spindle speed during hole making, countersinking parameters, spindle rapid feed parameters, hole making feed speed, countersinking feed speed) and conduct hole making tests on a 2 mm thick titanium alloy flat plate test piece on the tool test table to obtain the optimal hole making machining parameters;

[0014] Step 6: The system adopts a bus-type distributed communication structure. The upper computer coordinates and controls the robot with the end effector and the robot assembly auxiliary tooling to complete the tooling rotation control, robot positioning, and hole-making operations, thereby realizing the automated hole-making of the titanium alloy U-shaped thin-walled cover structure.

[0015] Step 7: Install the titanium alloy U-shaped thin-walled cover structure after drilling to the specified position of the product to verify the accuracy of the drilling position and the depth of the countersink.

[0016] Integrated processing of step drill bit hole making and countersinking.

[0017] The step drill processing area is equipped with a vacuum cleaner to clean up debris in real time during the hole making process.

[0018] The optimal hole-making processing parameters are: spindle hole-making speed 800 rpm, spindle countersinking speed 500 rpm, spindle feed speed 800 rpm, rapid feed speed 35 mm / s, hole-making feed speed 0.8 mm / s, and countersinking feed speed 0.3 mm / s.

[0019] The present invention realizes the integrated processing of automatic hole making and countersinking of titanium alloy U-shaped thin-walled cover-shaped structures, improves production efficiency and hole making accuracy, and greatly improves product consistency and stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of a step drill tool according to the present invention;

[0021] FIG2 is a schematic diagram of the robot assembly auxiliary tooling of the present invention, wherein Figure 2b yes Figure 2a A top view of Figure 2c yes Figure 2a side view. DETAILED DESCRIPTION

[0022] like Figure 1 As shown in Figures 2 and 3, the present invention uses a robot assembly auxiliary tooling to press and fix the workpiece, positions the workpiece through the side, bottom and circular holes of the tooling, and presses the workpiece onto a molded surface with positioning accuracy through a pressing block, thereby achieving pressing and positioning of the workpiece; the tooling is designed with a corresponding positioning reference, and a laser tracker can be used for system calibration.

[0023] A teach-in mode is used, and a laser tracker is used to calibrate the machining hole position to improve hole positioning accuracy. A customized stepped drill bit is used to achieve integrated hole making and countersinking. A high-suction vacuum cleaner is installed at the countersinking drilling site to remove debris in real time during the hole making process, achieving automatic removal of excess material.

[0024] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings.

[0025] Implementation process:

[0026] 1) The tool structure design is determined by the hole position characteristics of the workpiece (a row of countersunk holes with a spacing of 100 mm at the edge of the cover, and 6 countersunk holes located on the hyperboloid part, with a hole diameter of 5.2). The schematic diagram of the step drill tool is shown in Figure 1 The product is positioned through a 91mm locating hole and the outer surface.

[0027] 2) Based on the external and structural characteristics of the workpiece, a robot assembly auxiliary tooling was designed. The tooling primarily consists of left and right support columns, a rotating body, and a drive unit. A schematic diagram of the tooling is shown in Figure 2. This tooling has the following advantages: it can simultaneously clamp four quadrants of product, completing the entire hole-making task in a single clamping operation; it can switch workstations by rotating to accommodate the robot's workspace; once the workstation is rotated into position, a locking device eliminates backlash in the drive system, ensuring hole-making accuracy; and the workpiece is held in place by the tooling's positioning cylindrical bosses, side and bottom positioning surfaces, pressure blocks, and clamps.

[0028] 3) Complete the production of step drills and robot assembly auxiliary tooling according to design drawings.

[0029] 4) Complete the installation and debugging of robot assembly auxiliary tooling.

[0030] 5) Use a laser tracker to calibrate the reference points on the surface to be processed by the robot assembly auxiliary tooling to determine the spatial position of the hole to be processed in space.

[0031] 6) Use a laser tracker to measure the positioning accuracy and repeatability of the robot assembly auxiliary tooling. According to "General Rules for Machine Tool Inspection, Part 2: Determination of Positioning Accuracy and Repeatability of CNC Axis Lines," tooling positioning accuracy and repeatability are measured at nine points within the tooling's measurable rotation range, with a positive and negative overtravel of 3° each, to ensure that accuracy meets the design requirements for hole-making precision.

[0032] 7) Set different processing parameters (spindle speed during hole making, countersinking parameters, spindle rapid feed parameters, hole making feed speed, countersinking feed speed) and conduct hole making tests on a 2mm thick titanium alloy flat plate test piece on the tool test table to obtain the optimal hole making processing parameters.

[0033] 8) The system adopts a bus-type distributed communication structure, and coordinates and controls industrial robots (including end effectors), robot assembly auxiliary tooling and other equipment through the host computer to complete tooling rotation control, robot positioning, hole making and other operations, thereby realizing the automated hole making of titanium alloy U-shaped thin-walled cover-shaped structures.

[0034] 9) Install the titanium alloy U-shaped thin-walled cover structure after drilling to the specified position of the product to verify the accuracy of the drilling position and the depth of the countersink.

[0035] This invention utilizes an industrial robot in conjunction with a robotic assembly-assisted tooling device to verify process parameters for drilling holes in thin-walled titanium alloys. By integrating the robotic assembly-assisted tooling control system with the robot control system, this method enables efficient, high-precision, and high-quality automated drilling of U-shaped, thin-walled, hood-like structures in titanium alloys. Compared to manual drilling, automated drilling by robotics offers high precision and consistent quality, significantly reducing labor intensity and improving production efficiency. This method is widely applicable to verifying automated drilling processes for U-shaped, thin-walled, hood-like structures in titanium alloys.

Claims

1. A method for automatically making holes in a titanium alloy U-shaped thin-walled cover-shaped structure, characterized by: The following steps are involved: Step 1: Determine the tool structure design based on the hole position characteristics of the workpiece. The tool is designed as a step drill, and the product is positioned through the positioning hole and the outer surface; Step 2: Design the robot assembly auxiliary tooling according to the shape and structural characteristics of the workpiece. The tooling includes left and right supporting columns, a rotating body supported on them, and a driving unit. The driving unit drives the rotating body to rotate. The tooling can simultaneously clamp four quadrants of products, completing all hole-making tasks in one clamping. The workstations can be switched by rotation to adapt to the robot's workspace. Once the workstation is rotated into position, a locking device eliminates the backlash of the transmission system to ensure hole-making accuracy. The product is clamped and positioned by the positioning cylindrical boss, side positioning surfaces, bottom positioning surfaces, pressure blocks, and clamps on the tooling. The positioning cylindrical boss cooperates with the product's positioning hole, while the side positioning surfaces, bottom positioning surfaces, and outer surface of the product achieve positioning. The pressure blocks and clamps clamp the workpiece. Step 3: Use a laser tracker to calibrate the reference points on the surface to be processed by the robot assembly auxiliary tooling to determine the spatial position of the hole to be processed in space; Step 4: Use a laser tracker to measure the positioning accuracy and repeatability of the robot assembly auxiliary tooling to ensure that its accuracy meets the hole-making accuracy design requirements; Step 5: Set different processing parameters to conduct hole-making tests on a 2 mm thick titanium alloy flat plate test piece on the test tool stand to obtain the optimal hole-making processing parameters; Step 6: The system adopts a bus-type distributed communication structure, and coordinates the control of the robot with the end effector and the robot assembly auxiliary tooling through the host computer to complete the tooling rotation control, robot positioning, and hole making operations, thereby realizing the automated hole making of the titanium alloy U-shaped thin-walled cover structure.

2. The method for automatically making holes in a titanium alloy U-shaped thin-walled cover-shaped structure according to claim 1, wherein: Install the titanium alloy U-shaped thin-walled cover structure after drilling to the specified position of the product to verify the accuracy of the drilling position and the depth of the countersink.

3. The method for automatically making holes in a titanium alloy U-shaped thin-walled cover-shaped structure according to claim 1, wherein: Integrated processing of step drill bit hole making and countersinking.

4. The method for automatically making holes in a titanium alloy U-shaped thin-walled cover-like structure according to claim 1, wherein: The step drill processing area is equipped with a vacuum cleaner to clean up debris in real time during the hole making process.

5. The method for automatically making holes in a titanium alloy U-shaped thin-walled cover-shaped structure according to claim 1, wherein: The optimal hole-making processing parameters are: spindle hole-making speed 800 rpm, spindle countersinking speed 500 rpm, spindle feed speed 800 rpm, rapid feed speed 35 mm / s, hole-making feed speed 0.8 mm / s, and countersinking feed speed 0.3 mm / s.

6. The method for automatically making holes in a titanium alloy U-shaped thin-walled cover-like structure according to claim 1, characterized in that: In step 4, the positioning accuracy and repeatability of the tooling are measured by selecting 9 points at intervals of 30° within the measurable range of tooling rotation, with a positive and negative overtravel of 3° each, to ensure that its accuracy meets the hole-making accuracy design requirements.

7. The method for automatically making holes in a titanium alloy U-shaped thin-walled cover-like structure according to claim 1, wherein: In step 5, the processing parameters set include the spindle speed during hole making, countersinking parameters, spindle rapid feed parameters, hole making feed speed and countersinking feed speed.

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