Multi-channel numerical control grinding machine tool for machining outer spherical surface structure of ball head

Abstract

The invention discloses a multi-channel numerical control grinding machine tool for machining an outer spherical surface structure of a ball head, and relates to a grinding system for machining an outer spherical surface of a medical thighbone ball head. The multi-channel numerical control grinding machine tool is high in machining precision and production efficiency. The multi-channel numerical control grinding machine tool comprises a composite workbench and a linear servo driving module, wherein a workpiece servo main shaft module is arranged on the composite workbench; a grinding servo main shaft module is arranged on the linear servo driving module; the composite workbench comprises a vertical servo rotating shaft, and a workpiece servo feeding sliding table is arranged on the vertical servo rotating shaft. The workpiece servo main shaft module comprises a workpiece inner positioning and clamping fixture; an automatic online detection module is arranged on one side of the workpiece servo main shaft module; a linear servo sliding table is arranged on the linear servo driving module, and power of the linear servo sliding table is provided by a linear motor; a grinding floating cutter handle is installed on the grinding servo main shaft, and a cutter assembly is installed on the grinding floating cutter handle.

Description

Technical Field

[0001] The invention relates to the technical field of numerical control machine tools, in particular to a multi-channel numerical control grinding machine tool for machining an outer spherical surface structure of a ball head. Background Art

[0002] The femoral head is a medical structural component, which is often used in the treatment of artificial hip replacement. The main structure of the artificial hip joint is formed by the connection between the femoral head and the femoral stem.

[0003] The outer surface of the femoral head is a smooth spherical structure; the inner surface needs to be processed into a structure that can be adapted for installation with the femoral stem, usually having an inner spherical surface, a conical surface, an end face with a step or a threaded surface.

[0004] The development principle of spherical outer spherical surface grinding action is as follows: the workpiece needs to be positioned and installed on the spindle, the spherical workpiece needs to rotate counterclockwise along its own horizontal axis, and at the same time needs to swing and rotate along the vertical axis passing through the center of the ball. When an annular grinding wheel is used for grinding, the swing angle can be calculated. The grinding wheel shank is installed on the grinding spindle and rotates in the opposite direction to the workpiece, thereby realizing the movement required for the spherical grinding trajectory. When the grinding wheel spindle is fed axially, the basic requirements of the spherical grinding action can be achieved.

[0005] The complex structure inside and outside the femoral head places high demands on processing equipment, fixture equipment, drive technology, control system, overall mathematical model design and online detection system in the production process. Common femoral head products on the market are divided into metal alloys or ceramic materials, which have different requirements in processing accuracy and processing equipment, and are also a great challenge for manufacturers.

[0006] The main problems with the current production systems on the market are: the equipment spindle and other components are not rigid enough, have poor stability and low precision; the grinding spindle speed adjustment range is too small, and the equipment working accuracy is difficult to meet the engineering capability index standard; the roundness accuracy and surface roughness of the processed parts do not reach the ideal level; and the production efficiency is not high. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a multi-channel numerically controlled grinding machine tool with high machining accuracy and production efficiency for machining the outer spherical surface structure of a ball head.

[0008] The invention discloses a multi-channel numerically controlled grinding machine tool for machining the outer spherical surface structure of a ball head, comprising a composite workbench and a linear servo drive module, wherein a workpiece servo spindle module is arranged on the composite workbench; and a grinding servo spindle module is arranged on the linear servo drive module;

[0009] The composite workbench comprises a vertical servo rotating shaft, on which a workpiece servo feed slide capable of linear motion is arranged, and a workpiece servo spindle module is mounted on the workpiece servo feed slide;

[0010] The workpiece servo spindle module comprises a workpiece internal positioning and clamping fixture, on which a tool setting standard ceramic ball or a femoral ball part is installed;

[0011] An automatic online detection module is provided on one side of the workpiece servo spindle module, and the automatic online detection module includes a linear sensor arranged above the femoral ball part, and the position of the linear sensor in the vertical direction can be adjusted according to the instruction of the numerical control system;

[0012] The linear servo drive module is provided with a linear servo slide, the power of the linear servo slide is provided by a linear motor, and a protective device and a dustproof sealing belt synchronization device are provided outside the linear motor;

[0013] The grinding servo spindle module is arranged on the linear servo slide, and the grinding servo spindle module comprises a grinding servo spindle, a grinding floating tool holder is installed on the grinding servo spindle, and a tool assembly is installed on the grinding floating tool holder;

[0014] It also includes a tool changing robot, a grinding wheel servo spindle module and a rotary tool magazine module. The tool changing robot includes a slatted frame component, on which a manipulator angle cylinder is movably mounted, and on which a plurality of tools that do not interfere with each other can be placed simultaneously;

[0015] The rotary tool magazine module is arranged on one side of the tool changing robot, and the rotary tool magazine module includes a tool magazine rotary bearing support for placing a plurality of tools;

[0016] The rotary tool magazine module includes a rotary servo motor, which can drive the tool supported by the rotary bearing of the tool magazine to rotate to a designated tool change position.

[0017] The present invention is a multi-channel CNC grinding machine for processing the outer spherical structure of a ball head, wherein the workpiece servo spindle module also includes a front end flange and a discharge thin cylinder, the workpiece internal positioning clamping fixture includes a part loosening adjustment rod, the discharge thin cylinder can contact one end of the part loosening adjustment rod, and the other end of the part loosening adjustment rod is sequentially provided with an adjustable positioning cone rod, a fixed double nut, a clamping disc spring, a workpiece fixture positioning body and an intermediate cone pull rod, the fixed double nut, the clamping disc spring and the adjustable positioning cone rod are sequentially sleeved on the outside of the intermediate cone pull rod, the fixed double nut is fixedly connected to the intermediate cone pull rod, and the clamping The two ends of the tightening disc spring are respectively in contact with the fixed double nut and the workpiece fixture positioning body. The workpiece fixture positioning body is mounted on the outside of the adjustable positioning cone rod. The front end face of the workpiece fixture positioning body is used to position the external end face of the standard ceramic ball or femoral ball part for tool setting. The conical surface part at the front end of the adjustable positioning cone rod extends from the front end of the workpiece fixture positioning body to achieve positioning with the inner conical surface of the standard ceramic ball or femoral ball part for tool setting; the workpiece fixture positioning body is connected to the front end flange of the workpiece servo spindle module, and the end of the middle cone pull rod can position the inner end face of the standard ceramic ball or femoral ball part for tool setting.

[0018] The present invention is a multi-channel CNC grinding machine for processing the outer spherical structure of a ball head, wherein a servo motor and a lead screw pair are installed above the vertical servo rotating axis, an upper slider connecting an adjustment plate is movably installed on the servo motor and the lead screw pair, and a workpiece servo feed slide moves together with the upper slider connecting the adjustment plate.

[0019] The invention discloses a multi-channel numerically controlled grinding machine for machining the outer spherical surface structure of a ball head, wherein an annular guide pair is movably installed below the upper slide block connected to the adjustment plate, and the annular guide pair is installed on an arc-shaped guide support module.

[0020] The present invention is a multi-channel CNC grinding machine for processing the outer spherical structure of a ball head, wherein the automatic online detection module includes a double-sided support plate, a linear guide pair is vertically installed on the double-sided support plate, a transition connecting plate is movably installed on the linear guide pair and is driven by a detection thin cylinder, a front and rear adjustment block is connected to the transition connecting plate, a sensor adjustable fixed block is installed on the front and rear adjustment block, and a linear sensor is installed on the sensor adjustable fixed block.

[0021] The present invention is a multi-channel CNC grinding machine tool for processing the outer spherical structure of a ball head, wherein the protective device uses a synchronous belt to perform dust prevention treatment on the upper side of the linear motor; the dustproof sealing belt synchronization device includes a driving wheel and a tensioning wheel, and the driving wheels are respectively located at both ends of the synchronous belt to always keep the synchronous belt in a tensioned state.

[0022] The invention discloses a multi-channel numerically controlled grinding machine tool for machining the outer spherical surface structure of a ball head, wherein an absolute value encoder is arranged on one side of the linear servo slide.

[0023] The present invention discloses a multi-channel CNC grinding machine tool for processing the outer spherical structure of a ball head, wherein the grinding floating tool holder comprises a floating grinding wheel sleeve, a tool assembly is installed at one end of the floating grinding wheel sleeve, and an intermediate connecting sleeve is installed at the other end, the other end of the intermediate connecting sleeve is connected to the tail end tool holder, a slotted connecting pin passes through corresponding pin holes on the intermediate connecting sleeve and the tail end tool holder, and a retaining ring is fixed on the outside of the slotted connecting pin; the tail end tool holder is provided with an inner cavity, a spring is placed in the inner cavity along the movement direction of the tool, and one end of the intermediate connecting sleeve extends into the inner cavity of the tail end tool holder and contacts with the spring.

[0024] The invention discloses a multi-channel numerically controlled grinding machine tool for machining the outer spherical surface structure of a ball head, wherein a workbench protection ring is arranged outside the vertical servo rotating shaft.

[0025] The invention discloses a multi-channel numerically controlled grinding machine tool for processing the outer spherical surface structure of a ball head, which also comprises a bed. The bed adopts an integrally cast artificial marble structure and is provided with adjustable pads.

[0026] The multi-channel CNC grinding machine tool for processing the outer spherical surface structure of the ball head of the present invention is different from the prior art in that the multi-channel CNC grinding machine tool for processing the outer spherical surface structure of the ball head of the present invention is designed with a CNC composite worktable with the center of the workpiece rotation axis as the ball axis and the center of the revolution vertical axis tangent to the ball center to form the theoretical center of the ball, and can swing and rotate, thereby solving the problem of high-precision grinding processing of high-hardness medical ceramic femoral heads.

[0027] During grinding, according to the characteristics of high-hardness ceramic grinding, a linear servo motor drive is used to obtain high resolution, high positioning accuracy, large thrust, and flexible feeding, which can achieve online automatic compensation requirements.

[0028] The present invention utilizes a high-resolution online sensor to detect in real time the change in the diameter accuracy of the ground femoral ball, transmits the data back to the control system in real time, compares and determines with the set standard, and then the control system issues an instruction to correct the grinding wheel linear servo feed system to compensate and adjust the grinding wheel feed parameters, thereby ensuring the quality of part grinding and improving production efficiency.

[0029] The invention adopts a steel (protective cloth) belt type synchronous roller protection device, which has a compact structure, good sealing protection effect, beautiful appearance and low cost.

[0030] The present invention designs a ten-tool-position vertical rotary tool magazine, a quilting rack and a mechanical corner tool-changing robot, which has reliable tool-changing block speed, strong structural rigidity and good application effect.

[0031] The grinding accuracy of the invention is higher than the national standard of the product. The national standard for roundness is 0.005mm, and the processing accuracy of the invention is 0.002-0.003mm. The ball diameter accuracy can be controlled at 0.01mm, and the ball surface roughness only needs one fine polishing, with high processing efficiency and good quality.

[0032] The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head of the present invention will be further described below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a front view of a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0034] Figure 2 A top view of a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0035] Figure 3 It is a side view of a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0036] Figure 4 It is a front view of a composite workbench in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0037] Figure 5 It is a top view of a composite workbench in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0038] Figure 6 It is a side view of a composite workbench in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0039] Figure 7 An exploded view of a workpiece servo spindle module in a multi-channel CNC grinding machine tool for machining an outer spherical surface structure of a ball head according to the present invention;

[0040] Figure 8 It is a schematic diagram of the installation and disassembly states of the femoral ball parts in the multi-channel CNC grinding machine tool for machining the outer spherical surface structure of the ball head of the present invention;

[0041] Fig. 9 It is a structural schematic diagram of an automatic online detection module in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0042] Fig.10 It is a schematic diagram of the installation position of the adjustable fixing block of the sensor in the multi-channel CNC grinding machine tool for machining the outer spherical surface structure of the ball head according to the present invention;

[0043] Fig.11It is a structural schematic diagram of a support and positioning frame in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0044] Fig.12 A schematic diagram of the relative positions of a femoral ball part and a tool in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0045] Fig.13 It is a front view of a linear servo drive module in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0046] Fig.14 It is a top view of a linear servo drive module in a multi-channel CNC grinding machine tool for machining an outer spherical surface structure of a ball head according to the present invention;

[0047] Fig.15 It is a side view of a linear servo drive module in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0048] Fig.16 It is a structural schematic diagram of a grinding floating tool holder in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0049] Fig.17 An exploded view of a floating tool holder for grinding in a multi-channel CNC grinding machine tool for machining an outer spherical surface structure of a ball head according to the present invention;

[0050] Fig.18 It is a front view of a rotary tool magazine in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0051] Fig.19 It is a side view of a rotary tool magazine in a multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to the present invention;

[0052] The markings in the figure are as follows: 1-workpiece servo spindle module; 2-automatic online detection module; 3-linear sensor; 4-tool changing robot; 5-grinding wheel servo spindle module; 6-linear servo drive module; 8-rotating tool magazine module; 9-bed; 10-compound workbench; 11-workpiece internal positioning clamping fixture; 12-arc guide rail support module; 13-transition connecting plate; 14-double-side support plate; 15-sensor adjustable fixing block; 16-middle right-angle vertical plate; 17-linear guide pair; 18-detection Thin cylinder; 19-front and rear adjustment block; 21-femoral ball parts; 22-tool assembly; 23-grinding floating tool handle; 24-servo motor and screw pair; 25-parts release adjustment rod; 26-annular guide rail mounting support seat; 27-annular guide rail pair; 28-upper slider connecting adjustment plate; 29-unloading thin cylinder; 32-workpiece servo feed slide; 33-workbench protection ring; 34-vertical servo rotating shaft; 35-protective device; 36-slide pad; 37-double-side adjustment block; 38-linear Servo slide; 40-grinding servo spindle module; 41-absolute encoder; 42-dustproof seal with synchronization device; 43-linear motor; 44-two-dimensional micro-adjustment device; 45-tool change clamping cylinder; 46-manipulator angle cylinder; 47-manipulator connecting plate; 48-manipulator moving parts; 49-rotating tool magazine protective cover; 50-tool magazine rotary bearing support; 51-moving thin cylinder; 52-lateral moving slide; 53-vertical slide; 54-quilting frame component; 55-special clamping claw for tool handle; 5 6-rotary servo motor; 57-rotary tool magazine mounting bracket; 58-tool magazine air blowing and cleaning nozzle; 59-adjusting stud; 60-unloading rod; 61-end nut; 62-adjustable positioning cone rod; 63-fixed double nut; 64-clamping disc spring; 65-workpiece fixture positioning body; 66-middle cone pull rod; 67-tool setting standard ceramic ball; 68-fixing screw; 69-floating grinding wheel sleeve; 70-middle connecting sleeve; 71-slotted connecting pin; 72-circlip ring; 73-spring; 74-tail end tool handle. DETAILED DESCRIPTION

[0053] The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0054] Example

[0055] like Figure 1-Figure 3 As shown, the multi-channel CNC grinding machine tool for processing the outer spherical surface structure of the ball head of the present invention includes a bed 9, which adopts an integrally cast artificial marble structure, has good shock absorption, and has good stability under temperature changes. The bed 9 is equipped with an adjustable shim, and the horizontal accuracy of the bed 9 can be adjusted and fixed according to the standard.

[0056] A compound worktable 10 and a linear servo drive module 6 are installed on the bed 9; a workpiece servo spindle module 1 is installed on the compound worktable 10; a workpiece internal positioning and clamping fixture 11 is installed on the workpiece servo spindle module 1; the workpiece internal positioning and clamping fixture 11 is used to load the femoral ball part 21; a grinding servo spindle module 40 is installed on the linear servo drive module 6; a tool for grinding is installed on the grinding servo spindle module 40.

[0057] like Figure 4-Figure 6 As shown, the composite workbench 10 is installed in the middle of the bed, and the composite workbench 10 includes a vertical servo rotating shaft 34. A workbench protection ring 33 is provided on the outside of the vertical servo rotating shaft 34 to ensure the safety of the staff. The vertical servo rotating shaft 34 is used to realize the swinging process of the femoral ball part 21. A servo motor and a lead screw pair 24 are installed above the vertical servo rotating shaft 34, and an upper slider connecting the adjustment plate 28 is movably installed on the servo motor and the lead screw pair 24. The workpiece servo feed slide 32 moves together with the upper slider connecting the adjustment plate 28 to realize the linear feeding of the femoral ball part 21. The workpiece servo spindle module 1 is installed above the workpiece servo feed slide 32.

[0058] In this embodiment, the steps for realizing the rotation, fine-tuning feed and swinging functions of the femoral ball part 21 include: first installing the workpiece servo spindle module 1 on the workpiece servo feed slide 32 of the compound workbench 10, and then clamping the femoral ball part 21 on the workpiece servo spindle module 1; the workpiece servo spindle module 1 can set the spindle speed and direction according to the workpiece grinding needs, and the parameters of the workpiece servo spindle module 1 are controlled by the control system; the servo fine-tuning feed changes according to the different changes in the center position of the ball of the workpiece series model, and the workpiece servo feed slide 32 on the compound workbench 10 is controlled by the numerical control system to realize the axial fine adjustment of the workpiece; the swinging function of the workpiece is realized by controlling the rotation of the vertical servo rotating axis 34 on the compound workbench 10 by the numerical control system.

[0059] The vertical servo rotating shaft 34 and the workpiece servo feed slide 32 in the composite workbench 10 have an accuracy of 0.001mm, realizing the axial micro-adjustment function of the workpiece servo spindle module 1, while ensuring the swing and rotation function of the horizontal axis and the vertical axis through the center of the sphere of the spherical workpiece. The composite workbench 10 ensures that the Z axis of the spin center of the part is axially adjustable and tangent to the C axis of the revolution center, forming a mathematical model of the spherical motion trajectory. The composite workbench 10 adopts the super-rigidity design principle, the carrier load safety factor is greater than 8-10 times, and the precision life is expected to exceed 10 years.

[0060] An annular guide pair 27 is movably installed below the upper slider connected to the adjustment plate 28, and the annular guide pair 27 can support the workpiece servo feed slide 32 to swing in the horizontal plane under the action of the vertical servo rotating shaft 34. The annular guide pair 27 is installed on the arc-shaped guide support module 12, and the arc-shaped guide support module 12 includes an annular guide mounting support seat 26, and the annular guide mounting support seat 26 is fixedly installed on the bed 9.

[0061] The workpiece servo spindle module 1 is used to realize the axial rotation of the femoral ball component 21, and cooperates with the swing action of the vertical servo rotating shaft 34 in the composite workbench 10 and the linear feed action of the workpiece servo feed slide 32 to realize the grinding of the outer spherical surface of the femoral ball component 21. Figure 7 and Figure 8 As shown, the workpiece servo spindle module 1 includes a workpiece internal positioning and clamping fixture 11, a front end flange and a unloading thin cylinder 29, and the femoral ball part 21 to be processed is installed on the workpiece internal positioning and clamping fixture 11.

[0062] The workpiece internal positioning clamping fixture 11 includes a part loosening adjustment rod 25. The part loosening adjustment rod 25 includes an adjusting stud 59, a discharge rod 60 and an end nut 61 connected in sequence. The adjusting stud 59 and the end nut 61 are respectively installed at both ends of the discharge rod 60 and are coaxial with the discharge rod 60. The discharge thin cylinder 29 can abut against one end of the adjusting stud 59. When loading and unloading workpieces, the discharge thin cylinder 29 can push the adjusting stud 59 to move the part loosening adjustment rod 25 to the other side.

[0063] The other side of the end nut 61 is provided with an adjustable positioning cone rod 62 coaxial with the part loosening adjustment rod 25, a fixed double nut 63, a clamping disc spring 64, a workpiece fixture positioning body 65 and an intermediate cone pull rod 66 in sequence. The fixed double nut 63, the clamping disc spring 64 and the adjustable positioning cone rod 62 are sequentially sleeved on the outside of the intermediate cone pull rod 66. The fixed double nut 63 is located on the outside of the end of the intermediate cone pull rod 66 and is fixedly connected to the intermediate cone pull rod 66 by threads. The two ends of the clamping disc spring 64 are in contact with the fixed double nut 63 and the workpiece fixture positioning body 65 respectively. The workpiece fixture positioning body 65 is sleeved on the outside of the adjustable positioning cone rod 62, and the front end face of the workpiece fixture positioning body 65 can be used to position the outer end face of the workpiece. The front end of the adjustable positioning cone rod 62 is provided with a cone surface, and the cone surface portion of the adjustable positioning cone rod 62 extends from the front end of the workpiece fixture positioning body 65, and is positioned with the inner cone surface of the tool-setting standard ceramic ball 67 or the femoral ball part 21. The workpiece fixture positioning body 65 is connected to the front end flange of the workpiece servo spindle module 1 and is fixed by a fixing screw 68. The end of the intermediate cone pull rod 66 can be clamped and installed on the inner end surface of the tool-setting standard ceramic ball 67 or the femoral ball part 21. The positioning surfaces of the femoral ball part 21 are the inner cone surface and the end surface, and must meet the serialization requirements of the product, so the position of the large end size of the taper can be adjusted according to the product requirements, and the use of a disc spring tensioning method can ensure that the clamping force is constant and the accuracy consistency is good.

[0064] The steps for positioning, clamping and loosening the femoral ball part 21 in this embodiment include: installing the workpiece internal positioning clamping fixture 11 on the front end flange of the workpiece servo spindle module 1 and tightening it with a fixing screw 68; the loosening step includes starting the unloading thin cylinder 29 to feed the adjustment stud 59 to push the intermediate cone pull rod 66 through the unloading rod 60 and the end nut 61 to overcome the spring force of the clamping disc spring 64, and the intermediate cone pull rod 66 moves forward to push the workpiece, so that the adjustable positioning cone rod 62 is loosened from the positioning state, and the standard ceramic ball 67 or the femoral ball part 21 can be loaded and unloaded at this time; the clamping step includes reversing the unloading thin cylinder 29, and the elasticity of the clamping disc spring 64 will move the intermediate cone pull rod 66 backward, so that the adjustable positioning cone rod 62 is tightened to achieve workpiece positioning clamping. The positioning and repeated positioning of the femoral ball part 21 in this embodiment are accurate, which can not only improve the processing accuracy, but also provide a basis for the online detection module to obtain accurate data.

[0065] like Figure 9-12As shown, an automatic online detection module 2 is installed above the workpiece servo spindle module 1, and the automatic online detection module 2 includes a base plate, which is fixedly connected to the workpiece servo spindle module 1 below. A double-sided support plate 14 and a middle right-angle vertical plate 16 are fixedly installed on the base plate. A linear guide pair 17 is vertically installed on the double-sided support plate 14, and a transition connecting plate 13 is movably installed on the linear guide pair 17, and is driven by a thin detection cylinder 18 to adjust the vertical position of the transition connecting plate 13. A front and rear adjustment block 19 is connected to the transition connecting plate 13 by bolts, and the position of the front and rear adjustment block 19 can be adjusted by adjusting the position of the bolts. A sensor adjustable fixed block 15 is installed on the front and rear adjustment block 19, and the sensor adjustable fixed block 15 can further perform fine adjustment in the vertical direction. A high-resolution linear sensor 3 is installed on the sensor adjustable fixed block 15. The automatic online detection module 2 can adjust multiple structures in different dimensions, which is convenient for processing workpieces of different models.

[0066] The main feature of the grinding process is that the wear of the grinding wheel is uncertain and cannot be accurately confirmed. In order to obtain the processing accuracy under automatic grinding, it is necessary to monitor the dimensional changes of the femoral head in real time during the grinding process and control the processing accuracy of the femoral head by compensating the feeding of the grinding wheel.

[0067] The steps for realizing the online automatic detection and automatic compensation functions in this embodiment include: installing the automatic online detection module 2 on the workpiece servo spindle module 1, and then installing the linear sensor 3 on the adjustable fixed block 15, and then fixing the adjustable fixed block 15 on the front and rear adjustment blocks 19, and then fixing the front and rear adjustment blocks 19 on the transition connecting plate 13, forming a linear motion pair through the transition connecting plate 13 and the detection thin cylinder 18, and assembling the double-sided support plates 14 and the middle right-angle vertical plate 16 into a support positioning frame; when the workpiece rotates, the detection thin cylinder 18 is controlled to change direction, and the linear sensor 3 is sent to the measurement position, the linear sensor 3 automatically measures, and the detection parameters are transmitted to the numerical control system for filing, and the changes in the grinding amount size of the workpiece are detected in real time, and at the same time, they are compared with the internal standard value in real time. When the detection is qualified, it automatically exits, and the number of detections and the compensation amount can be set according to needs; the compensation function is realized by the control system receiving the data of the linear sensor 3 and instructing the linear servo slide 38 to micro-feed.

[0068] like Figure 11-13As shown, the linear servo drive module 6 is located on the opposite side of the workpiece servo spindle module 1, and is used to install a tool to grind the femoral ball part 21. The linear servo drive module 6 specifically includes a slide washer 36, which is fixedly connected to the bed 9, and the height of the slide washer 36 can be adjusted. A linear servo slide 38 is installed on the slide washer 36, and the linear servo slide 38 is driven by a linear motor 43 located below the linear servo slide 38. The feeding of the medical ceramic material grinding spindle requires high resolution (0.0001mm), high positioning accuracy (0.001mm) and high repeatability positioning accuracy (0.001mm). The linear motor 43 drive can generate electromagnetic flexible thrust and the feeding accuracy is controllable. It can meet the technical requirements of automatic grinding compensation when used in conjunction with the linear sensor 3.

[0069] A protective device 35 and a dustproof sealing belt synchronization device 42 are provided on the outside of the linear motor 43. The protective device 35 uses a synchronous belt to perform dustproof treatment on the top of the linear motor 43; the dustproof sealing belt synchronization device 42 includes a driving wheel and a tensioning wheel. The driving wheels are respectively located at both ends of the synchronous belt. The two driving wheels work on demand and cooperate with the tensioning wheel to allow the synchronous belt to move in two directions and always keep it in a tensioned state to prevent debris from falling into the area where the linear motor 43 is located.

[0070] A double-sided adjustment block 37 is provided between the slide shim 36 and the guard 35 to facilitate adjustment of the position of the guard 35. An absolute encoder 41 is provided on one side of the linear servo slide 38. The absolute encoder 41 specifically includes an absolute magnetic scale and a reading head, which is used to accurately control the feed amount of the slide.

[0071] A grinding servo spindle module 40 is installed above the linear servo slide 38 , and a two-dimensional fine adjustment device 44 is provided between the grinding servo spindle module 40 and the linear servo slide 38 to facilitate fine adjustment of the position of the grinding servo spindle module 40 .

[0072] In this embodiment, the steps for realizing the rotation and feeding functions of the grinding servo spindle module 40 include: installing the grinding servo spindle module 40 on the linear servo slide 38, installing the linear servo slide 38 on the slide pad 36, and installing the slide pad 36 on the bed 9; controlling the rotation speed and torque requirements of the grinding servo spindle module 40 through the servo system, and controlling the rapid feeding, multiple grinding feeding, grinding wheel wear compensation, rapid retraction, positioning tool changing and other functions of the linear servo slide 38 through the numerical control system, and the high-resolution absolute encoder 41 ensures the realization of various precision indicators of the linear servo slide 38.

[0073] The grinding servo spindle module 40 includes a grinding servo spindle with an accuracy of 0.001 mm, and the rotation speed and torque requirement of the grinding servo spindle are controlled by a servo system. A grinding floating tool holder 23 is installed at the front end of the grinding servo spindle, and a tool assembly 22 for grinding the femoral ball part 21 is installed on the grinding floating tool holder 23.

[0074] like Fig.16 and Fig.17 As shown, the grinding floating tool handle 23 includes a floating grinding wheel sleeve 69, one end of which is mounted with the tool assembly 22, and the other end is mounted with an intermediate connecting sleeve 70. The other end of the intermediate connecting sleeve 70 is connected to the tail end tool handle 74. In this embodiment, the model of the tail end tool handle 74 is HSKE-40. The connection between the intermediate connecting sleeve 70 and the tail end tool handle 74 is achieved by a slotted connecting pin 71 and a retaining ring 72. The slotted connecting pin 71 passes through the corresponding pin holes on the intermediate connecting sleeve 70 and the tail end tool handle 74, and the retaining ring 72 is fixed to the outside of the slotted connecting pin 71. The tail end tool handle 74 is provided with an inner cavity, and a spring 73 is placed in the inner cavity along the direction of tool movement. One end of the intermediate connecting sleeve 70 extends into the inner cavity of the tail end tool handle 74 and contacts with one end of the spring 73.

[0075] The assembly process of the grinding floating tool handle 23 in this embodiment includes: installing the floating grinding wheel sleeve 69 on the middle connecting sleeve 70, installing the spring 73 in the inner cavity of the tail tool handle 74, and the middle connecting sleeve 70 and the tail tool handle 74 are connected by a slotted connecting pin 71 and a circlip ring 72.

[0076] The present invention adopts the installation mode of floating fine grinding handle 23 to improve the clamping accuracy. The installation error is eliminated by setting the intermediate connecting sleeve 70 and the spring 73. Since the workpiece is clamped with high accuracy at one time, the polishing efficiency of the part by replacing the floating polishing wheel is very high and the effect is good.

[0077] like Fig.18 and Fig.19 As shown, a tool changing robot 4, a grinding wheel servo spindle module 5 and a rotary tool magazine module 8 are provided on one side of the bed 9. The tool changing robot 4 includes a quilting frame component 54, on which a lateral movable slide 52 is movably mounted, and on which a vertical slide 53 is movably mounted. A manipulator connecting plate 47 is mounted at the end of the vertical slide 53, and the manipulator connecting plate 47 is connected to a manipulator angle cylinder 46 through a manipulator moving component 48, and the power of the manipulator moving component 48 is provided by a moving thin cylinder 51. The manipulator angle cylinder 46 has a rotation angle of 180°, and multiple tool handles can be loaded at the same time without interfering with each other. A tool changing clamping cylinder 45 is mounted on the manipulator angle cylinder 46, and a tool handle special clamping claw 55 is mounted on the tool changing clamping cylinder 45, and a tool to be replaced is mounted on the tool handle special clamping claw 55.

[0078] The rotary tool magazine module 8 includes a rotary tool magazine mounting bracket 57, and the rotary tool magazine mounting bracket 57 is mounted on the bed 9. A tool magazine rotary bearing support 50 is mounted on the rotary tool magazine mounting bracket 57, and multiple tools are placed around the tool magazine rotary bearing support 50. In this embodiment, there are ten tools. In the femoral ball head grinding process, the rough grinding-semi-fine grinding-fine grinding-polishing, the workpiece is clamped once to complete all processes, and the tool can be automatically changed in sequence to complete the grinding process. The tool magazine rotary bearing support 50 is also equipped with a tool magazine air blowing cleaning nozzle 58 and a rotary tool magazine protective cover 49, which are used for cleaning and protection respectively.

[0079] The grinding wheel servo spindle module 5 includes a rotary servo motor 56, which drives the tool on the tool magazine rotary bearing support 50 to rotate to a designated tool change position.

[0080] The assembly steps of the automatic tool changing system in this embodiment include: installing and fixing the gantry component 54 on the bed 9, installing the transverse moving slide 52 and the vertical slide 53 on the gantry component 54, installing the manipulator angle cylinder 46 on the vertical slide 53 through the manipulator connecting plate 47 and the manipulator moving component 48, and installing the tool changing clamping cylinder 45 on the manipulator angle cylinder 46; installing the tool magazine rotary bearing support 50 on the rotary tool magazine mounting bracket 57, installing the rotary tool magazine mounting bracket 57 on the bed 9, and installing each tool handle for replacement and the rotary tool magazine protective cover 49 on the tool magazine rotary bearing support 50; installing the tool handle special clamping claw 55 on the tool changing clamping cylinder 45, and installing the rotary servo motor 56 and the tool magazine air blowing cleaning nozzle 58 on the tool magazine rotary bearing support 50, forming a rotary tool magazine with ten HSK-E40 tool handles, which can realize the automatic tool replacement of the grinding wheel tool handle according to the grinding process requirements.

[0081] During the grinding process, the grinding spindle stays at the specified position as required, the tool changing robot moves to the specified position to automatically replace the tool handle that needs to be replaced, the manipulator angle cylinder 46 replaces the required new tool handle and returns to its original position, places the replaced tool handle in the specified position of the rotary tool magazine module 8, and then takes out the new tool required for the next step and returns it to standby. While the robot returns to replace the new tool, the grinding wheels can work at the same time without interfering with each other.

[0082] The working principle of the multi-channel CNC grinding machine tool for machining the outer spherical surface structure of the ball head of the present invention includes:

[0083] Turn on the machine, the program function automatically detects and assembles the femoral ball part 21 and clamps it;

[0084] Start the automatic grinding process and the cooling system at the same time;

[0085] The workpiece servo spindle module 1 rotates automatically, and the composite worktable 10 starts to swing;

[0086] The grinding servo spindle module 40 automatically changes the required tool holder;

[0087] The grinding servo spindle rotates, and the linear servo slide 38 automatically feeds;

[0088] During the first rough grinding process, the grinding process is automatically detected online, and the tool is changed after the rough grinding is completed;

[0089] The second rough grinding process is performed with automatic online detection during grinding, and the tool is changed after the rough grinding is completed;

[0090] Fine grinding, automatic online detection during grinding, tool change after fine grinding is completed;

[0091] Rough grinding process, automatic online detection during grinding, tool change after rough grinding is completed;

[0092] After the grinding work is completed, the machine will automatically stop, the door will be opened, and the workpieces will be manually loaded and unloaded;

[0093] Repeat the above steps.

[0094] The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of the ball head of the present invention designs a CNC composite worktable with the center of the workpiece rotation axis as the ball axis and the center of the revolution vertical axis tangent to the ball center to form the ball theoretical center, and can swing and rotate, thereby solving the problem of high-precision grinding machining of high-hardness medical ceramic femoral heads.

[0095] During grinding, according to the characteristics of high-hardness ceramic grinding, a linear servo motor drive is used to obtain high resolution, high positioning accuracy, large thrust, and flexible feeding, which can achieve online automatic compensation requirements.

[0096] The present invention utilizes a high-resolution online sensor to detect in real time the change in the diameter accuracy of the ground femoral ball, transmits the data back to the control system in real time, compares and determines with the set standard, and then the control system issues an instruction to correct the grinding wheel linear servo feed system to compensate and adjust the grinding wheel feed parameters, thereby ensuring the quality of part grinding and improving production efficiency.

[0097] The invention adopts a steel (protective cloth) belt type synchronous roller protection device, which has a compact structure, good sealing protection effect, beautiful appearance and low cost.

[0098] The present invention designs a ten-tool-position vertical rotary tool magazine, a quilting rack and a mechanical corner tool-changing robot, which has reliable tool-changing block speed, strong structural rigidity and good application effect.

[0099] The grinding accuracy of the invention is higher than the national standard of the product. The national standard for roundness is 0.005mm, and the processing accuracy of the invention is 0.002-0.003mm. The ball diameter accuracy can be controlled at 0.01mm, and the ball surface roughness only needs one fine polishing, with high processing efficiency and good quality.

[0100] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A multi-channel CNC grinding machine for machining the outer spherical surface structure of a ball head, characterized in that: It includes a composite workbench and a linear servo drive module. The composite workbench is provided with a workpiece servo spindle module; the linear servo drive module is provided with a grinding servo spindle module; The composite workbench comprises a vertical servo rotating shaft, on which a workpiece servo feed slide capable of linear motion is arranged, and a workpiece servo spindle module is mounted on the workpiece servo feed slide; The workpiece servo spindle module comprises a workpiece internal positioning and clamping fixture, on which a tool setting standard ceramic ball or a femoral ball part is installed; An automatic online detection module is provided on one side of the workpiece servo spindle module, and the automatic online detection module includes a linear sensor arranged above the femoral ball part, and the position of the linear sensor in the vertical direction can be adjusted according to the instruction of the numerical control system; The linear servo drive module is provided with a linear servo slide, the power of the linear servo slide is provided by a linear motor, and a protective device and a dustproof sealing belt synchronization device are provided outside the linear motor; The grinding servo spindle module is arranged on the linear servo slide, and the grinding servo spindle module comprises a grinding servo spindle, a grinding floating tool holder is installed on the grinding servo spindle, and a tool assembly is installed on the grinding floating tool holder; It also includes a tool changing robot, a grinding wheel servo spindle module and a rotary tool magazine module. The tool changing robot includes a slatted frame component, on which a manipulator angle cylinder is movably mounted, and on which a plurality of tools that do not interfere with each other can be placed simultaneously; The rotary tool magazine module is arranged on one side of the tool changing robot, and the rotary tool magazine module includes a tool magazine rotary bearing support for placing a plurality of tools; The rotary tool magazine module includes a rotary servo motor, which can drive the tool supported by the rotary bearing of the tool magazine to rotate to a designated tool change position.

2. The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to claim 1, characterized in that: The workpiece servo spindle module also includes a front end flange and a unloading thin cylinder. The workpiece internal positioning clamping fixture includes a part loosening adjustment rod. The unloading thin cylinder can contact one end of the part loosening adjustment rod. The other end of the part loosening adjustment rod is sequentially provided with an adjustable positioning cone rod, a fixed double nut, a clamping disc spring, a workpiece fixture positioning body and an intermediate cone pull rod. The fixed double nut, the clamping disc spring and the adjustable positioning cone rod are sequentially sleeved on the outside of the intermediate cone pull rod. The fixed double nut is fixedly connected to the intermediate cone pull rod, and the two ends of the clamping disc spring are respectively connected to the fixed double nut The nut is in contact with the workpiece fixture positioning body, the workpiece fixture positioning body is sleeved on the outside of the adjustable positioning cone rod, the front end face of the workpiece fixture positioning body is used to locate the external end face of the standard ceramic ball or femoral ball part for tool setting, the conical surface part at the front end of the adjustable positioning cone rod extends from the front end of the workpiece fixture positioning body, and realizes positioning with the internal conical surface of the standard ceramic ball or femoral ball part for tool setting; the workpiece fixture positioning body is connected to the front end flange of the workpiece servo spindle module, and the end of the middle cone pull rod can locate the inner end face of the standard ceramic ball or femoral ball part for tool setting.

3. The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to claim 1, characterized in that: A servo motor and a lead screw pair are installed above the vertical servo rotating shaft, an upper slider connecting an adjustment plate is movably installed on the servo motor and the lead screw pair, and the workpiece servo feed slide moves together with the upper slider connecting the adjustment plate.

4. The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to claim 3, characterized in that: An annular guide pair is movably installed below the upper sliding block connected to the adjustment plate, and the annular guide pair is installed on the arc-shaped guide support module.

5. The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to claim 1, characterized in that: The automatic online detection module includes a double-sided support plate, on which a linear guide pair is vertically installed, a transition connecting plate is movably installed on the linear guide pair and is driven by a thin detection cylinder, a front and rear adjustment block is connected to the transition connecting plate, a sensor adjustable fixed block is installed on the front and rear adjustment block, and a linear sensor is installed on the sensor adjustable fixed block.

6. The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to claim 1, characterized in that: The protective device uses a synchronous belt to perform dust prevention on the top of the linear motor; the dustproof sealing belt synchronization device includes a driving wheel and a tensioning wheel, and the driving wheels are respectively located at both ends of the synchronous belt to always keep the synchronous belt in a tensioned state.

7. The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to claim 1, characterized in that: An absolute encoder is arranged on one side of the linear servo slide.

8. The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to claim 1, characterized in that: The grinding floating tool handle includes a floating grinding wheel sleeve, a tool assembly is installed on one end of the floating grinding wheel sleeve, and an intermediate connecting sleeve is installed on the other end. The other end of the intermediate connecting sleeve is connected to the tail end tool handle, and the slotted connecting pin passes through the corresponding pin holes on the intermediate connecting sleeve and the tail end tool handle, and the retaining ring is fixed on the outside of the slotted connecting pin; the tail end tool handle is provided with an inner cavity, and a spring is placed in the inner cavity along the movement direction of the tool, and one end of the intermediate connecting sleeve extends into the inner cavity of the tail end tool handle and contacts with the spring.

9. The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to claim 1, characterized in that: A workbench protection ring is arranged outside the vertical servo rotating shaft.

10. The multi-channel CNC grinding machine tool for machining the outer spherical surface structure of a ball head according to claim 1, characterized in that: The utility model also comprises a bed body, which adopts an integrally cast artificial marble structure and is provided with adjustable shims.

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