A device and method for symmetrical turning and milling composite processing of rod-shaped specimens

Abstract

The present invention discloses a device and method for symmetrical turning and milling composite processing of rod-shaped specimens, which includes: CNC turning equipment, including a workpiece chuck and a tailstock, one end of the rod-shaped specimen is mounted on the workpiece chuck, and the other end of the rod-shaped specimen is pressed against the tailstock; a large pallet, the upper part of which is symmetrically provided with a front middle drag plate assembly and a rear middle pallet assembly; and also includes a front 360-degree rotary tool holder and a rear 360-degree rotary tool holder, a front cross slide and a rear cross slide, a front milling electric spindle and a rear milling electric spindle, and an axial feed structure, and milling cutters are installed on the front milling electric spindle and the rear milling electric spindle. The present invention solves the problems of bending and cutting, workpiece deformation, annular tool marks that are prone to stress concentration, and poor dimensional accuracy when slender specimen workpieces are processed using conventional CNC turning equipment, and the processing efficiency is significantly improved. At the same time, it also has the advantages of simple construction and operation, and can perform symmetrical turning and milling composite processing on various forms of rod-shaped specimens and slender shaft workpieces.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing, and in particular to a device and a method for symmetrical turning and milling composite processing of a rod-shaped sample. Background Art

[0002] Since the reform and opening up, my country's comprehensive strength has made a qualitative leap, especially for modern mechanical processing and manufacturing technology, which represents the development level of the manufacturing industry and is the best embodiment of overall strength. It not only reflects the level of industrial technology, but also is a manifestation of science and technology. However, with the progress of the times, various new materials and new processing requirements have put forward higher requirements for mechanical processing equipment and methods, and at the same time, the requirements for mechanical processing accuracy and equipment reliability as well as the processing requirements for various new materials have been further improved. Most of the previous processing processes were popular and could not meet the actual needs of modern new materials for processing efficiency and processing quality, especially the requirements of material research laboratories for mechanical specimen processing quality and processing efficiency. Due to the large processing allowance of rod-shaped mechanical specimens, and generally slender shaft workpieces, the processing difficulty is relatively large, and the surface processing quality and dimensional accuracy are difficult to control, especially for conventional rod-shaped tensile specimens and fatigue specimens.

[0003] Conventional lathe-type turning equipment is currently used for processing. Due to the single-sided tool holder cutting and the installation of ordinary turning tools, when processing slender specimens, the single-sided tool extrudes the specimen sideways during cutting, and the specimen workpiece is prone to bending, deformation, and poor dimensional accuracy. In addition, for new materials that are not easy to cut, low processing efficiency and poor surface quality are caused: and because the workpiece rotates in conventional lathe-type turning equipment, the turning tool does not move, so the surface of the processed rod-shaped specimen is an annular knife pattern around the circumference. This knife pattern is very likely to produce stress concentration during tensile and fatigue mechanical tests, which has a great impact on the test, and the true mechanical properties of the material cannot be obtained, which restricts the quality and efficiency of scientific research. In addition, conventional turning equipment can only use a single turning tool for cutting when processing rod-shaped specimens, and the processing efficiency is low. In order to improve the processing quality and efficiency of rod-shaped tensile and fatigue specimens, it is necessary to customize and develop processing needs to meet the directional needs of processing and production. Summary of the invention

[0004] Based on this, it is necessary to provide a device and method for symmetrical turning and milling composite processing of rod-shaped specimens, which can avoid the occurrence of annular tool marks on the workpiece surface, bending of the tool during processing, deformation of the workpiece, and poor dimensional accuracy, and significantly improve the processing efficiency, in order to address the above-mentioned technical problems.

[0005] The present invention provides a device for symmetrical turning and milling composite processing of a rod-shaped sample, which comprises:

[0006] The CNC turning equipment comprises a workpiece chuck and a tailstock, one end of the rod-shaped sample is mounted on the workpiece chuck, and the other end of the rod-shaped sample is pressed against the tailstock;

[0007] A large support plate, on the upper part of which a front middle drag plate assembly and a rear middle support plate assembly are symmetrically installed, wherein the front middle drag plate assembly and the rear middle support plate assembly are respectively located on both sides of the rod-shaped specimen;

[0008] The front 360-degree rotary tool rest and the rear 360-degree rotary tool rest are respectively mounted on the front middle carriage assembly and the rear middle support plate assembly, and the front 360-degree rotary tool rest and the rear 360-degree rotary tool rest are respectively mounted with a front cross slide and a rear cross slide, and the front cross slide and the rear cross slide are respectively mounted with a front milling electric spindle and a rear milling electric spindle, and milling cutters are mounted on the front milling electric spindle and the rear milling electric spindle; the front cross slide and the rear cross slide can respectively adjust the front, rear, left, and right positions of the front milling electric spindle and the rear milling electric spindle;

[0009] An axial feeding structure, used for driving the large support plate to drive the milling cutter to move and feed along the axial direction of the rod-shaped specimen;

[0010] Among them, the front center drag plate assembly and the rear center support plate assembly can respectively drive the front 360-degree rotating tool holder and the rear 360-degree rotating tool holder to drive the milling cutter to move and feed along the radial direction of the rod-shaped sample.

[0011] In one of the embodiments, the axial feeding structure includes a feed guide screw, which is horizontally arranged on the CNC turning equipment, and the feed guide screw is threadedly connected to the large support plate.

[0012] In one embodiment, the front center carriage assembly and the rear center carriage assembly each include a slide, a motor, a lead screw and a lead screw nut;

[0013] The upper surface of the large support plate is provided with a radial guide rail, and the slide table is slidably arranged on the radial guide rail of the large support plate, and the slide table 25 can radially approach or move away from the rod-shaped sample along the radial guide rail;

[0014] The motor is installed on the side of the large support plate, and the motor is connected to the numerical control system and one end of the lead screw respectively;

[0015] The other end of the screw rod is inserted into the screw rod nut, and the screw rod nut is fixedly connected to the bottom of the slide.

[0016] In one of the embodiments, the maximum radial movement distance of the front center carriage assembly and the rear center support plate assembly along the rod-shaped specimen is less than half of the maximum clamping diameter of the workpiece chuck.

[0017] In one embodiment, the radial lengths of the front center drag plate assembly and the rear center pallet assembly are respectively greater than the radial lengths of the front 360-degree rotating tool holder and the rear 360-degree rotating tool holder, and are less than half the length of the radial guide rail, and the axial widths of the front center drag plate assembly and the rear center pallet assembly are not greater than the axial width of the large pallet.

[0018] In one embodiment, the front 360-degree rotary tool holder includes a front tool holder rotary body and a front rotary transmission motor, and the rear 360-degree rotary tool holder includes a rear tool holder rotary body and a rear rotary transmission motor, the front tool holder rotary body and the rear tool holder rotary body are respectively mounted on the front middle carriage assembly and the rear middle support plate assembly, and the front tool holder rotary body and the rear tool holder rotary body are respectively mounted on the upper surfaces of the front tool holder rotary body and the rear tool holder rotary body;

[0019] The front rotary transmission motor and the rear rotary transmission motor are connected to the numerical control system; the front rotary transmission motor and the rear rotary transmission motor are used to drive the front cross slide and the rear cross slide to rotate in a horizontal plane relative to the front tool holder rotating body and the rear tool holder rotating body.

[0020] In one embodiment, the front cross slide and the rear cross slide both include an upper slide and a lower slide, the upper slide can slide relative to the lower slide along the axis and radial direction of the rod-shaped specimen, and the upper slide and the lower slide are respectively locked in lateral and radial positions by lateral adjustment screws and radial adjustment screws.

[0021] In one embodiment, the front milling electric spindle includes a front milling electric spindle motor, a front spindle and a front milling cutter chuck connected in sequence, and the rear milling electric spindle includes a rear milling electric spindle motor, a rear spindle and a rear milling cutter chuck connected in sequence. The front milling electric spindle and the rear milling electric spindle use high-speed milling electric spindle motors, and the front milling cutter chuck and the rear milling cutter chuck are used to install the milling cutter.

[0022] In addition, the present invention also provides a method for using a device for symmetrical turning and milling composite machining of a rod-shaped specimen, which comprises the following steps:

[0023] S1. Install one end of the rod-shaped specimen on the workpiece chuck of the CNC turning equipment, and fix the other end of the rod-shaped specimen with the tailstock;

[0024] S2, installing the milling cutter, fine-tuning the front cross slide and the rear cross slide to perform radial tool alignment of the rod-shaped specimen, and then adjusting the front cross slide and the rear cross slide to perform axial tool alignment of the rod-shaped specimen, so that the milling cutters on both sides of the rod-shaped specimen symmetrically and evenly contact the surface to be processed;

[0025] S3. Compile a machining program for the rod-shaped specimen in the numerical control system, determine the axial and radial feed parameters, set the rotation speeds of the front milling electric spindle motor and the rear milling electric spindle motor, and set the rotation speed of the workpiece chuck, so that the rotation speeds of the front milling electric spindle motor and the rear milling electric spindle motor are higher than the rotation speed of the workpiece chuck by a certain range of multiples;

[0026] S4. The front milling electric spindle and the rear milling electric spindle are started simultaneously, and the rod-shaped specimen is subjected to turning-milling composite processing according to the programmed processing program trajectory.

[0027] The above-mentioned device and method for symmetrical turning and milling composite processing of rod-shaped specimens, by symmetrically setting milling cutters on CNC turning equipment, using CNC turning equipment to drive the rod-shaped specimen to rotate, and the milling cutter self-rotates to turn and mill composite processing of the rod-shaped specimen, so that the rod-shaped specimen is symmetrically and balancedly stressed, and solves the problems of bending, tool yielding, workpiece deformation, and poor dimensional accuracy when slender specimen workpieces are processed using conventional CNC turning equipment, and the processing efficiency is significantly improved. At the same time, by adjusting the speed of the milling cutter and the rod-shaped specimen, the speed of the front milling electric spindle and the rear milling electric spindle is higher than the speed of the turning equipment spindle within a certain range, so that the surface of the rod-shaped specimen after processing is an arc-shaped cutting pattern when the milling cutter is cutting, avoiding the annular cutting pattern generated when conventional turning equipment processes rod-shaped specimens, which causes stress concentration during specimen testing and affects the test results. It also has the advantages of simple construction, simple operation, and symmetrical turning and milling composite processing of various forms of rod-shaped specimens and slender shaft workpieces. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a diagram showing the use state of the device for symmetrical turning and milling composite processing of a rod-shaped sample according to the present invention;

[0029] Figure 2 It is a partial structural schematic diagram of the device for symmetrical turning and milling composite processing of a rod-shaped sample of the present invention;

[0030] Figure 3 It is a top view of the device for symmetrical turning and milling composite processing of a rod-shaped sample of the present invention;

[0031] Figure 4 It is a structural schematic diagram of the front middle carriage assembly of the device for symmetrical turning and milling compound processing of a rod-shaped specimen of the present invention;

[0032] Figure 5 It is a structural schematic diagram of a front cross slide or a rear cross slide of a device for symmetrical turning and milling composite processing of a rod-shaped sample according to the present invention;

[0033] Figure 6 It is a state diagram of the maximum clamping diameter of the workpiece chuck of the device for symmetrical turning and milling composite machining of a rod-shaped specimen of the present invention;

[0034] Figure 7It is a diagram of the installation positions of the front 360-degree rotating tool rest and the rear 360-degree rotating tool rest of the device for symmetrical turning and milling compound processing of a rod-shaped sample of the present invention;

[0035] Figure 8 It is a structural schematic diagram of a large support plate of a device for symmetrical turning and milling composite processing of a rod-shaped sample according to the present invention;

[0036] Fig. 9 It is a schematic structural diagram of a rod-shaped specimen of the device for symmetrical turning and milling composite processing of a rod-shaped specimen of the present invention. DETAILED DESCRIPTION

[0037] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Preferred embodiments of the present invention are provided in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0038] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0040] In the present invention, for the convenience of description, it is assumed that the axial direction parallel to the rod-shaped sample 22 is the Z direction (lateral direction), and the axial direction perpendicular to the rod-shaped sample 22 in the horizontal plane is the X direction (radial direction).

[0041] See also Figure 1-9 As shown, an embodiment of the present invention provides a device for symmetrical turning and milling composite processing of rod-shaped specimens, including a CNC turning device, a large support plate 1, a front 360-degree rotating tool holder, a rear 360-degree rotating tool holder and an axial feeding structure.

[0042] Specifically, the CNC turning equipment includes a workpiece chuck 18 and a tailstock 19, one end of the rod-shaped sample 22 is mounted on the workpiece chuck 18, and the other end of the rod-shaped sample 22 is pressed against the tailstock 19;

[0043] Optionally, a front middle carriage assembly 2 and a rear middle carriage assembly 3 are symmetrically installed on the upper part of the large carriage 1, and the front middle carriage assembly 2 and the rear middle carriage assembly 3 are respectively located on both sides of the rod-shaped specimen 22;

[0044] The front 360-degree rotary tool rest and the rear 360-degree rotary tool rest are respectively mounted on the front middle carriage assembly 2 and the rear middle support plate assembly 3, and the front 360-degree rotary tool rest and the rear 360-degree rotary tool rest are respectively mounted with a front cross slide 8 and a rear cross slide 9, and the front cross slide 8 and the rear cross slide 9 are both mounted with a front milling electric spindle and a rear milling electric spindle, and the front milling electric spindle and the rear milling electric spindle are both mounted with a milling cutter; the front cross slide 8 and the rear cross slide 9 can respectively adjust the front, rear, left, and right positions of the front milling electric spindle and the rear milling electric spindle;

[0045] The axial feeding structure is used to drive the large support plate 1 to drive the milling cutter to move and feed along the axial direction of the rod-shaped sample; the front center drag plate assembly 2 and the rear center support plate assembly 3 can respectively drive the front 360-degree rotating tool holder and the rear 360-degree rotating tool holder to drive the milling cutter to move and feed along the radial direction of the rod-shaped sample 22.

[0046] In one embodiment of the present invention, the axial feeding structure includes a feed guide screw 16, which is horizontally arranged on the CNC turning device, and the feed guide screw 16 is threadedly connected to the large support plate 1. Specifically, one end of the guide screw 16 can be connected to the drive motor, and the other end of the guide screw 16 can be rotatably fixed on the CNC turning device. When the drive motor drives the guide screw 16 to rotate, the large support plate 1 can be driven to move along the Z direction.

[0047] In one embodiment of the present invention, the front middle carriage assembly 2 and the rear middle carriage assembly 3 each include a slide 25, a motor 26, a screw 27 and a screw nut 28;

[0048] Specifically, a radial guide rail 30 is provided on the upper surface of the large support plate 1, and the slide 25 is slidably arranged on the radial guide rail 30. The slide 25 can radially approach or move away from the rod-shaped sample 22 along the radial guide rail 30; that is, the slide 25 is constrained by the position of the radial guide rail 30, so that the slide 25 can move back and forth along the X direction.

[0049] Further, the motor 26 is mounted on the side of the large support plate 1, for example, the mounting hole of the motor 26 is fixed to the side of the large support plate 1 with screws, and the motor 26 is connected to the numerical control system 17 and one end of the screw rod 27 respectively; the other end of the screw rod 27 is inserted into the screw rod nut 28, and the screw rod nut 28 is fixedly connected to the bottom of the slide 25. In the present invention, the motor 26 can drive the screw rod 27 to rotate, thereby driving the slide 25 to move forward and backward along the radial guide rail 30.

[0050] Furthermore, the maximum radial movement distance of the front center carriage assembly 2 and the rear center support plate assembly 3 along the rod-shaped specimen 22 is less than half of the maximum clamping diameter of the workpiece chuck 18. In this way, the radial movement of the front center carriage assembly 2 and the rear center support plate assembly 3 can be limited to avoid pinching off the rod-shaped specimen 22.

[0051] Optionally, in order to improve safety, the radial lengths of the front center drag plate assembly 2 and the rear center pallet assembly 3 are respectively greater than the radial lengths of the front 360-degree rotating tool holder and the rear 360-degree rotating tool holder, and are less than half the length of the radial guide rail 30, and the axial widths of the front center drag plate assembly 2 and the rear center pallet assembly 3 are not greater than the axial width of the large pallet 1.

[0052] The front 360-degree rotary tool holder of the present invention comprises a front tool holder rotary body 6 and a front rotary transmission motor 4, and the rear 360-degree rotary tool holder comprises a rear tool holder rotary body 7 and a rear rotary transmission motor 5, the front tool holder rotary body 6 and the rear tool holder rotary body 7 are respectively mounted on the front middle carriage assembly 2 and the rear middle support plate assembly 3, and the upper surfaces of the front tool holder rotary body 6 and the rear tool holder rotary body 7 are respectively mounted with a front cross slide 8 and a rear cross slide 9;

[0053] The front rotary transmission motor 4 and the rear rotary transmission motor 5 are connected to the numerical control system 17; the front rotary transmission motor 4 and the rear rotary transmission motor 5 are used to drive the front cross slide 8 and the rear cross slide 9 to rotate in a horizontal plane relative to the front tool holder rotating body 6 and the rear tool holder rotating body 7.

[0054] The front cross slide 8 and the rear cross slide 9 both include an upper slide and a lower slide. The upper slide can slide relative to the lower slide along the axis and radial direction of the rod-shaped sample 22, and the upper slide and the lower slide are locked in the lateral and radial directions by means of a lateral adjustment screw 23 and a radial adjustment screw 24, respectively.

[0055] Furthermore, the front milling electric spindle includes a front milling electric spindle motor 10, a front spindle 12 and a front milling cutter chuck 14 connected in sequence, and the rear milling electric spindle includes a rear milling electric spindle motor 11, a rear spindle 13 and a rear milling cutter chuck 15 connected in sequence, and the front milling cutter chuck 14 and the rear milling cutter chuck 15 are used to install the milling cutter. In the embodiment of the present invention, the front milling cutter chuck 14 and the rear milling cutter chuck 15 are relatively arranged on the front and rear sides of the rod-shaped specimen 22, the front milling electric spindle motor 10 drives the milling cutter on the front milling cutter chuck 14 to rotate through the front spindle 12, and the rear milling electric spindle motor 11 drives the milling cutter on the rear milling cutter chuck 15 to rotate through the rear power head spindle 13, thereby realizing the milling of the rod-shaped specimen 22.

[0056] In one embodiment of the present invention, a method for using symmetrical turning and milling composite machining of a rod-shaped specimen comprises the following steps:

[0057] S1. Mount one end of the rod-shaped sample 22 on the workpiece chuck 18 of the CNC turning equipment, and fix the other end of the rod-shaped sample 22 with the tailstock 19;

[0058] S2, install the milling cutter, fine-tune the front cross slide 8 and the rear cross slide 9 to perform radial tool alignment of the rod-shaped sample 22, and then adjust the front cross slide 8 and the rear cross slide 9 to perform axial tool alignment of the rod-shaped sample 22, so that the milling cutters on both sides of the rod-shaped sample 22 symmetrically and evenly contact the surface to be processed; specifically, fine-tuning the axial (Z-direction) parameters of the front cross slide 8 and the rear cross slide 9 includes: performing Z-direction tool alignment by contacting the end face of the rod-shaped sample 22 by the milling cutter, so that the rotation center axes of the front power head spindle 12 and the rear power head spindle 13 are on the same axis and symmetrically and evenly contact the rod-shaped sample 22, and performing X-direction tool alignment by contacting the outer circle of the rod-shaped sample 22 by the milling cutter, and adjusting the X-direction parameters of the cross slide so that the milling cutters on both sides of the rod-shaped sample 22 symmetrically and evenly contact the rod-shaped sample 22.

[0059] S3. Compile a machining program for the rod-shaped specimen 22 in the numerical control system 17, determine the axial and radial feed parameters, and set the rotation speeds of the front milling electric spindle and the rear milling electric spindle; specifically, take the outer circular contour of the rod-shaped specimen 22 as the machining program cycle walking trajectory of the large carriage 1, the front center carriage assembly 2 and the rear center support assembly 3, determine the X-direction and Z-direction feed parameters of the large carriage 1, the front center carriage assembly 2 and the rear center support assembly 3, use the X-direction feed parameter of the front center carriage assembly 2 and the rear center support assembly 3 as the X-direction feed amount per tool cycle, and set the spindle of the rod-shaped specimen 22. Speed, X-axis feed per cut cycle, Z-axis feed per revolution, front milling electric spindle and rear milling electric spindle speed, in order to improve the surface quality and avoid the appearance of annular knife marks on the surface of the processed rod-shaped specimen, which causes stress concentration during the test, the speed of the front milling electric spindle and the rear milling electric spindle is higher than the spindle speed of the turning equipment in a certain range. Taking the rod specimen size recommended in the "Standard for Axial Force Control Method of Metal Material Fatigue Test" (GB / T15248-94) as an example, the commonly used setting is that the speed of the front milling electric spindle and the rear milling electric spindle is 2-50 times the spindle speed of the turning equipment.

[0060] S4, the workpiece chuck 18 and the milling cutter are started at the same time, and the rod-shaped sample 22 is subjected to turning and milling compound processing according to the programmed processing program trajectory. Specifically, the program is started, the large carriage 1, the front middle carriage assembly 2 and the rear middle support plate assembly 3 are moved to the rod-shaped sample 22, and the front middle carriage assembly 2 and the rear middle support plate assembly 3 are fed to the program preset position, so that the milling cutters installed on the front milling cutter chuck 14 and the rear milling cutter chuck 15 contact the rod-shaped sample 22 symmetrically on the left and right, and the rod-shaped sample 22 is fed in the X direction and the Z direction according to the programmed processing program trajectory, so as to realize symmetrical turning and milling compound processing. Embodiment 1:

[0061] The new TiB2 / Al7075 composite aluminum round bar blank is selected to process the rod-shaped specimen. The rod-shaped specimen size recommended by the "Standard for Axial Force Control Methods of Metallic Material Fatigue Test" (GB / T15248-94) is still taken as an example. The processing steps are as follows:

[0062] 1). The material is a round bar with a diameter of 20 mm and a length of 170 mm. One end of the bar-shaped specimen 22 is mounted on the workpiece chuck 18 of the CNC turning equipment, and the other end is fixed with the tailstock 19 of the turning equipment.

[0063] 2). Install a suitable milling cutter on the front milling cutter chuck 14. Use a round nose double-edged ball head milling cutter with a diameter of 5mm, a total length of 40mm, and a blade length of 15mm. Fine-tune the Z-axis parameters of the front cross slide 8. Perform Z-axis tool alignment by contacting the end face of the rod-shaped specimen 22 through the milling cutter, so that the front power head spindle 12 evenly contacts the rod-shaped specimen 22. Perform X-axis tool alignment by contacting the outer circle of the rod-shaped specimen 22 through the milling cutter. Adjust the X-axis parameters of the front cross slide 8 so that the milling cutter of the front milling cutter chuck 14 evenly contacts the rod-shaped specimen 22.

[0064] 3). Compile a machining program in the numerical control system 17, and use the outer contour of the rod-shaped specimen 22 as the machining program cycle walking trajectory of the large carriage 1 and the front center carriage assembly 2, determine the X- and Z-direction feed parameters of the large carriage 1 and the front center carriage assembly 2, use the X-direction feed parameter of the front center carriage assembly 2 as the cycle feed per cut, set the spindle speed of the rod-shaped specimen 22 to 100 revolutions per minute, set the front milling electric spindle speed to 400 revolutions per minute, set the X-direction cycle feed per cut to 1mm per cut, and set the Z-direction feed to 0.3mm per revolution, start the front milling electric spindle 12, start the program, move the large carriage 1 and the front center carriage assembly 2 to the rod-shaped specimen 22, and feed the front center carriage assembly 2 to the position preset by the program, so that the milling cutter installed on the front milling cutter chuck 14 contacts the rod-shaped specimen 22, and feed the rod-shaped specimen 22 in the X and Z directions according to the compiled machining program trajectory to achieve symmetrical turning and milling composite machining.

[0065] The status of the rod-shaped specimen 22 during the machining process was observed and evaluated. During the machining process of the rod-shaped specimen 22, the rotation speeds of the front milling electric spindle and the rod-shaped specimen 22 were both slow, the rotation speed matching was not appropriate, and the left-right symmetrical balanced cutting was not used for the turning-milling composite machining of the specimen workpiece. The single-sided tool squeezed the specimen workpiece, and a slight tool deflection occurred during the machining process. The surface quality of the rod-shaped specimen 22 after machining was average. The parallel section dimensions of the rod-shaped specimen 22 were measured, and the error of the 38mm length parallel section was 0.05mm. Embodiment 2:

[0066] The new TiB2 / Al7075 composite aluminum round bar blank is still selected, and the rod specimen size recommended by the "Standard for Axial Force Control Methods of Metallic Material Fatigue Test" (GB / T15248-94) is still taken as an example. The front milling electric spindle and the rear milling electric spindle speed of the embodiment 1, as well as the spindle speed of the rod specimen 22 are adjusted to process the rod specimen. The processing steps are as follows:

[0067] 1). The material is a round bar with a diameter of 20 mm and a length of 170 mm. One end of the bar-shaped specimen 22 is mounted on the workpiece chuck 18 of the CNC turning equipment, and the other end is fixed with the tailstock 19 of the turning equipment.

[0068] 2). Install a suitable milling cutter on the front milling cutter chuck 14 and the rear milling cutter chuck 15. The milling cutter is a round nose double-edged ball head milling cutter with a diameter of 5 mm, a total length of 40 mm, and a blade length of 15 mm. Fine-tune the Z-direction parameters of the front cross slide 8 and the rear cross slide 9 to compensate for the Z-direction wear of the tool in Example 1. Perform Z-direction tool alignment by contacting the end face of the rod-shaped sample 22 through the milling cutter, so that the rotation center axes 21 of the front power head spindle 12 and the rear power head spindle 13 are on the same axis and symmetrically and evenly contact the rod-shaped sample 22. Perform X-direction tool alignment by contacting the outer circle of the rod-shaped sample 22 through the milling cutter, adjust the X-direction parameters of the front cross slide 8 and the rear cross slide 9, compensate for the X-direction wear of the tool in Example 1, and make the milling cutters of the front milling cutter chuck 14 and the rear milling cutter chuck 15 symmetrically and evenly contact the rod-shaped sample 22.

[0069] 3). Compile a machining program in the numerical control system 17, and use the outer contour of the rod-shaped specimen 22 as the machining program cycle walking trajectory of the large carriage 1, the front center carriage assembly 2 and the rear center pallet assembly 3, determine the X-direction and Z-direction feed parameters of the large carriage 1, the front center carriage assembly 2 and the rear center pallet assembly 3, and use the X-direction feed parameter of the front center carriage assembly 2 and the rear center pallet assembly 3 as the cycle feed per cut. Set the spindle speed of the rod-shaped specimen 22 to 800 revolutions per minute, the front milling electric spindle and the rear milling electric spindle to 5000 revolutions per minute, and set the X-direction cycle feed per cut to 1000 revolutions per minute. 1mm, the Z-axis feed amount is set to 0.3mm per revolution, the rotary spindle, front milling electric spindle and rear milling electric spindle of the rod-shaped specimen 22 are started at the same time, the program is started, the large slide 1, the front center slide assembly 2 and the rear center support plate assembly 3 are moved to the rod-shaped specimen 22, the front center slide assembly 2 and the rear center support plate assembly 3 are fed to the position preset by the program, so that the milling cutters installed on the front milling cutter chuck 14 and the rear milling cutter chuck 15 contact the rod-shaped specimen 22 symmetrically on the left and right, and the rod-shaped specimen 22 is fed in the X and Z directions according to the compiled machining program trajectory to achieve symmetrical turning and milling compound machining.

[0070] The status of the rod-shaped specimen 22 during the machining process was observed and evaluated. It was found that the front milling electric spindle and the rear milling electric spindle can achieve an operating speed of 5000-20000 rpm. The excellent surface quality of the rod-shaped specimen 22 after machining can be obtained at a speed of 5000 rpm. Since the front milling electric spindle and the rear milling electric spindle are located on both sides of the rod-shaped specimen, the left and right symmetrical and balanced cutting is achieved. No tool letting-down phenomenon occurs during the machining of the rod-shaped specimen 22. The parallel section dimensions of the rod-shaped specimen 22 after machining are measured, and the error of the 38mm length parallel section is less than 0.005mm. The milling cutters installed on the front milling electric spindle and the rear milling electric spindle rotate at high speed to form a turning-milling compound, which greatly improves the machining efficiency and reduces tool wear. Embodiment three:

[0071] The new TiB2 / Al6061 composite aluminum round bar blank is selected to process the rod-shaped specimen. The rod-shaped specimen size recommended by the "Standard for Axial Force Control Methods of Metallic Material Fatigue Test" (GB / T15248-94) is still taken as an example. The processing steps are as follows:

[0072] 1). The material is a round bar with a diameter of 20mm and a length of 170mm. One end of the bar-shaped specimen 22 is installed on the workpiece chuck 18 of the CNC turning equipment, and the other end is fixed with the tailstock 19 of the turning equipment.

[0073] 2). Install suitable milling cutters on the front milling cutter chuck 14 and the rear milling cutter chuck 15. Use a round nose double-edged ball head milling cutter with a diameter of 5mm, a total length of 40mm, and a blade length of 15mm. Fine-tune the Z-direction parameters of the front cross slide 8 and the rear cross slide 9. Perform Z-direction tool alignment by contacting the end face of the rod-shaped specimen 22 through the milling cutter, so that the rotation center axes 21 of the front power head spindle 12 and the rear power head spindle 13 are on the same axis and symmetrically and evenly contact the rod-shaped specimen 22. Perform X-direction tool alignment by contacting the outer circle of the rod-shaped specimen 22 through the milling cutter, and adjust the X-direction parameters of the front cross slide 8 and the rear cross slide 9 so that the milling cutters of the front milling cutter chuck 14 and the rear milling cutter chuck 15 symmetrically and evenly contact the rod-shaped specimen 22.

[0074] 3). Compile a machining program in the numerical control system 17, and use the outer contour of the rod-shaped specimen 22 as the machining program cycle walking trajectory of the large carriage 1, the front center carriage assembly 2 and the rear center pallet assembly 3, determine the X-direction and Z-direction feed parameters of the large carriage 1, the front center carriage assembly 2 and the rear center pallet assembly 3, and use the X-direction feed parameter of the front center carriage assembly 2 and the rear center pallet assembly 3 as the cycle feed per cut. Set the spindle speed of the rod-shaped specimen workpiece 22 to 2000 rpm, the front milling electric spindle and the rear milling electric spindle to 2000 rpm, and set the X-direction cycle feed per cut to 1 per cut. mm, the Z-direction feed amount is set to 0.3 mm per revolution, the rotary spindle of the rod-shaped specimen 22, the front power head spindle 12 and the rear power head spindle 13 are started simultaneously, the program is started, the large slide 1, the front center slide assembly 2 and the rear center support plate assembly 3 are moved to the rod-shaped specimen 22, the front center slide assembly 2 and the rear center support plate assembly 3 are fed to the position preset by the program, so that the milling cutters installed on the front milling cutter chuck 14 and the rear milling cutter chuck 15 contact the rod-shaped specimen 22 symmetrically on the left and right, and the rod-shaped specimen 22 is fed in the X and Z directions according to the compiled machining program trajectory to achieve symmetrical turning and milling compound machining.

[0075] The status of the rod-shaped specimen 22 during machining was observed and evaluated. Although there was no tool letting-down phenomenon during machining of the rod-shaped specimen 22, the spindle speeds of the front and rear milling electric spindles and the rod-shaped specimen 22 were not properly matched, and the speeds of the front and rear milling electric spindles were not 2-50 times that of the spindle speed of the turning equipment. As a result, slight annular tool marks appeared on the surface of the rod-shaped specimen after machining, causing stress concentration during sample testing. Embodiment 4:

[0076] Continue to use the new TiB2 / Al6061 composite aluminum round bar blank, and still take the rod specimen size recommended by the "Standard for Axial Force Control Methods of Metallic Material Fatigue Test" (GB / T15248-94) as an example to process the rod specimen. The processing steps are as follows:

[0077] 1). The material is a round bar with a diameter of 20mm and a length of 170mm. One end of the bar-shaped specimen 22 is installed on the workpiece chuck 18 of the CNC turning equipment, and the other end is fixed with the tailstock 19 of the turning equipment.

[0078] 2). Install suitable milling cutters on the front milling cutter chuck 14 and the rear milling cutter chuck 15. Use a round nose double-edged ball head milling cutter with a diameter of 5mm, a total length of 40mm, and a blade length of 15mm. Fine-tune the Z-direction parameters of the front cross slide 8 and the rear cross slide 9. Perform Z-direction tool alignment by contacting the end face of the rod-shaped specimen 22 through the milling cutter, so that the rotation center axes 21 of the front milling electric spindle and the rear milling electric spindle are on the same axis and symmetrically and evenly contact the rod-shaped specimen 22. Perform X-direction tool alignment by contacting the outer circle of the rod-shaped specimen 22 through the milling cutter, and adjust the X-direction parameters of the front cross slide 8 and the rear cross slide 9 so that the milling cutters of the front milling cutter chuck 14 and the rear milling cutter chuck 15 symmetrically and evenly contact the rod-shaped specimen 22.

[0079] 3). Compile a machining program in the numerical control system 17, and use the outer contour of the rod-shaped specimen 22 as the machining program cycle walking trajectory of the large carriage 1, the front center carriage assembly 2 and the rear center pallet assembly 3, determine the X-direction and Z-direction feed parameters of the large carriage 1, the front center carriage assembly 2 and the rear center pallet assembly 3, and use the X-direction feed parameter of the front center carriage assembly 2 and the rear center pallet assembly 3 as the cycle feed per cut. Set the spindle speed of the rod-shaped specimen workpiece 22 to 1000 rpm, the front milling electric spindle and the rear milling electric spindle to 6000 rpm, and set the X-direction cycle feed per cut to 1 per cut. mm, the Z-direction feed amount is set to 0.3 mm per revolution, the rotary spindle of the rod-shaped specimen 22, the front power head spindle 12 and the rear power head spindle 13 are started simultaneously, the program is started, the large slide 1, the front center slide assembly 2 and the rear center support plate assembly 3 are moved to the rod-shaped specimen 22, the front center slide assembly 2 and the rear center support plate assembly 3 are fed to the position preset by the program, so that the milling cutters installed on the front milling cutter chuck 14 and the rear milling cutter chuck 15 contact the rod-shaped specimen 22 symmetrically on the left and right, and the rod-shaped specimen 22 is fed in the X and Z directions according to the compiled machining program trajectory to achieve symmetrical turning and milling compound machining.

[0080] The speeds of the front and rear milling electric spindles were adjusted so that their speeds were six times that of the spindle speed of the rod-shaped sample 22. The status of the rod-shaped sample 22 during the machining process was observed and evaluated. No tool letting-off phenomenon occurred during the machining of the rod-shaped sample 22. The surface quality of the rod-shaped sample 22 after machining was excellent, and no annular tool marks appeared. The parallel section dimensions of the rod-shaped sample 22 were measured, and the error of the 38mm length parallel section was less than 0.005mm, and there was no obvious wear on the tool.

[0081] In some of the above embodiments, by processing two groups of new aluminum-based composite materials and fine-tuning the processing methods and parameters according to the material characteristics, the surface quality and dimensional accuracy after processing are achieved, and the deformation of the slender rod-shaped sample 22 is significantly improved.

[0082] In summary, the advantages of the present invention are:

[0083] 1. In some embodiments, a front milling electric spindle and a rear milling electric spindle are respectively installed on the front center slide assembly 2 and the rear center support plate assembly 3, so that the rotation centers of the front milling electric spindle and the rear milling electric spindle are on the same axis, and left-right balanced symmetrical X-direction and Z-direction feed milling composite processing is performed on slender shaft specimens, so that the specimen workpiece is subjected to left-right symmetrical force, thereby effectively solving the problem of single-sided tool squeezing the specimen workpiece when the slender shaft specimen workpiece is processed by conventional turning equipment, causing tool letting and deformation of the specimen workpiece, poor dimensional accuracy, and other problems.

[0084] 2. In some embodiments, the milling cutter can be fed and turned along the X-direction or Z-direction, and the milling cutter can also rotate and mill by itself, forming a turning-milling composite processing, so the feed depth and feed speed can be increased. Compared with conventional turning equipment for processing rod-shaped specimens, the turning tool does not rotate and can only turn the specimen in the X-direction or Z-direction, thereby greatly improving the processing efficiency of the specimen using the turning-milling composite processing.

[0085] 3. In some embodiments, when processing rod-shaped specimens, the milling speed of the milling electric spindle is increased and the rotation speed of the specimen workpiece is reduced, so that the rotation speeds of the front milling electric spindle and the rear milling electric spindle are higher than the spindle speed of the turning equipment within a certain range of multiples. Therefore, the surface of the specimen after processing can obtain arc-shaped cutting lines when the milling cutter is cutting, thereby avoiding the annular cutting tool lines generated when conventional turning equipment processes rod-shaped specimens, which causes stress concentration and affects the test results.

[0086] 4. In some embodiments, the X-axis and Z-axis parameters of the front milling electric spindle and the rear milling electric spindle can be manually fine-tuned through the front cross slide and the rear cross slide to solve the tool alignment and milling cutter wear compensation, so that the milling cutters installed on the front milling electric spindle and the rear milling electric spindle can symmetrically and evenly contact the sample workpiece to ensure dimensional consistency and dimensional stability during the processing. This method is simple to operate and easy to use.

[0087] 5. In some embodiments, the sample workpiece is subjected to turning-milling composite processing by symmetrically balancing the front milling electric spindle and the rear milling electric spindle. Since the front milling electric spindle and the rear milling electric spindle adopt high-speed milling electric spindle motors, the speed can be easily increased to 5000-20000 revolutions per minute during milling processing, thereby solving the problem of turning at a lower limit speed when ordinary turning equipment is used, and the influence of the rough knife marks on the surface finish of the sample after processing is solved. Therefore, the surface finish of the sample obtained after turning-milling composite processing is significantly improved, and the dimensional accuracy of the parallel section of the sample is significantly improved.

[0088] 6. In some embodiments, the symmetrical turning-milling compound processing device can be installed on the existing conventional CNC turning equipment, and only simple modification of the equipment is required. It is easy to build and operate, and can perform symmetrical turning-milling compound processing on various forms of rod-shaped specimens and slender shaft workpieces.

[0089] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0090] The above-described embodiments only express several implementation methods of the present application, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present application, which all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the attached claims.

Claims

1. A method for using a symmetrical turning and milling compound processing device for a rod-shaped specimen, characterized in that: The following steps are involved: S1. Mount one end of a rod-shaped sample (22) on a workpiece chuck (18) of a CNC turning device, and fix the other end of the rod-shaped sample (22) with a tailstock (19); S2, installing a milling cutter, fine-tuning the front cross slide (8) and the rear cross slide (9) to perform radial tool alignment of the rod-shaped specimen (22), and then adjusting the front cross slide (8) and the rear cross slide (9) to perform axial tool alignment of the rod-shaped specimen (22), so that the milling cutters on both sides of the rod-shaped specimen (22) symmetrically and evenly contact the surface to be processed; S3, compiling a machining program for the rod-shaped specimen (22) in the numerical control system (17), determining axial and radial feed parameters, setting the rotation speeds of the front milling electric spindle motor (10) and the rear milling electric spindle motor (11), and setting the rotation speed of the workpiece chuck (18), so that the rotation speeds of the front milling electric spindle motor (10) and the rear milling electric spindle motor (11) are higher than the rotation speed of the workpiece chuck (18) by a certain range of multiples; S4, the front milling electric spindle and the rear milling electric spindle are started simultaneously, and the rod-shaped specimen (22) is subjected to turning-milling composite processing according to the programmed processing program trajectory; The device for symmetrical turning and milling composite processing of a rod-shaped specimen comprises: A numerically controlled turning device, comprising a workpiece chuck (18) and a tailstock (19), wherein one end of the rod-shaped sample (22) is mounted on the workpiece chuck (18), and the other end of the rod-shaped sample (22) is pressed against the tailstock (19); A large support plate (1) is symmetrically provided with a front middle carriage assembly (2) and a rear middle carriage assembly (3) on its upper portion, wherein the front middle carriage assembly (2) and the rear middle carriage assembly (3) are respectively located on two sides of the rod-shaped specimen (22); A front 360-degree rotary tool rest and a rear 360-degree rotary tool rest are respectively mounted on the front center carriage assembly (2) and the rear center carriage assembly (3); a front cross slide (8) and a rear cross slide (9) are respectively mounted on the front 360-degree rotary tool rest and the rear 360-degree rotary tool rest; a front milling electric spindle and a rear milling electric spindle are respectively mounted on the front cross slide (8) and the rear cross slide (9); milling cutters are mounted on the front milling electric spindle and the rear milling electric spindle; the front cross slide (8) and the rear cross slide (9) can respectively adjust the front, rear, left, and right positions of the front milling electric spindle and the rear milling electric spindle; the rotation centers of the front milling electric spindle and the rear milling electric spindle are on the same axis; An axial feeding structure, used for driving the large support plate (1) to drive the milling cutter to move and feed along the axial direction of the rod-shaped specimen; The front center carriage assembly (2) and the rear center support plate assembly (3) are capable of respectively driving the front 360-degree rotating tool holder and the rear 360-degree rotating tool holder to drive the milling cutter to move and feed along the radial direction of the rod-shaped specimen (22).

2. The method of using the device for symmetrical turning and milling composite machining of a rod-shaped specimen as claimed in claim 1, characterized in that: The axial feeding structure comprises a feeding guide screw (16), wherein the feeding guide screw (16) is horizontally arranged on the numerically controlled turning device, and the feeding guide screw (16) is threadedly connected to the large support plate (1).

3. The method of using the device for symmetrical turning and milling composite machining of a rod-shaped specimen as claimed in claim 2, characterized in that: The front center carriage assembly (2) and the rear center support assembly (3) both include a slide (25), a motor (26), a screw (27) and a screw nut (28); A radial guide rail (30) is provided on the upper surface of the large support plate (1), and the slide table (25) is slidably arranged on the radial guide rail (30). The slide table (25) can radially approach or move away from the rod-shaped sample (22) along the radial guide rail (30); The motor (26) is mounted on a side of the large support plate (1), and the motor (26) is respectively connected to a numerical control system (17) and one end of the lead screw (27); The other end of the screw rod (27) is inserted into the screw rod nut (28), and the screw rod nut (28) is fixedly connected to the bottom of the slide table (25).

4. The method of using the device for symmetrical turning and milling composite machining of a rod-shaped specimen as claimed in claim 3, characterized in that: The maximum radial movement distance of the front center carriage assembly (2) and the rear center support plate assembly (3) along the rod-shaped specimen (22) is less than half of the maximum clamping diameter of the workpiece chuck (18).

5. The method for using the device for symmetrical turning and milling composite machining of a rod-shaped specimen as claimed in claim 4, characterized in that: The radial lengths of the front center carriage assembly (2) and the rear center support plate assembly (3) are respectively greater than the radial lengths of the front 360-degree rotary tool holder and the rear 360-degree rotary tool holder, and are less than half the length of the radial guide rail (30); and the axial widths of the front center carriage assembly (2) and the rear center support plate assembly (3) are not greater than the axial width of the large support plate (1).

6. The method for using the device for symmetrical turning and milling composite machining of a rod-shaped specimen as claimed in claim 5, characterized in that: The front 360-degree rotary tool holder comprises a front tool holder rotary body (6) and a front rotary transmission motor (4), and the rear 360-degree rotary tool holder comprises a rear tool holder rotary body (7) and a rear rotary transmission motor (5), the front tool holder rotary body (6) and the rear tool holder rotary body (7) are respectively mounted on the front middle carriage assembly (2) and the rear middle support plate assembly (3), and the upper surfaces of the front tool holder rotary body (6) and the rear tool holder rotary body (7) are respectively mounted with a front cross slide (8) and a rear cross slide (9); The front rotary transmission motor (4) and the rear rotary transmission motor (5) are connected to the numerical control system (17); the front rotary transmission motor (4) and the rear rotary transmission motor (5) are used to drive the front cross slide (8) and the rear cross slide (9) to rotate in a horizontal plane relative to the front tool holder rotating body (6) and the rear tool holder rotating body (7).

7. The method of using the device for symmetrical turning and milling composite machining of a rod-shaped specimen as claimed in claim 1, characterized in that: The front cross slide (8) and the rear cross slide (9) both comprise an upper slide and a lower slide, the upper slide being able to slide relative to the lower slide along the axis and radial direction of the rod-shaped specimen (22), and the upper slide and the lower slide being locked in position in the lateral and radial directions by means of a lateral adjustment screw (23) and a radial adjustment screw (24), respectively.

8. The method for using the device for symmetrical turning and milling composite machining of a rod-shaped specimen as claimed in claim 1, characterized in that: The front milling electric spindle comprises a front milling electric spindle motor (10), a front spindle (12) and a front milling cutter chuck (14) which are connected in sequence, and the rear milling electric spindle comprises a rear milling electric spindle motor (11), a rear spindle (13) and a rear milling cutter chuck (15) which are connected in sequence, and the front milling cutter chuck (14) and the rear milling cutter chuck (15) are used to install the milling cutter.

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