Summary: MC340/TWIN is the machining center of double main shaft that German STAMA company produces, because burn down is serious, cannot restore primary system. Technical reformation job uses German SIEMENS-840D to control a system to change the Japanese FANUC-15M system that primary machine tool deploys, involve technology of many hard, software, article curtly introduced those who concern to transform method and technology.
Machining center of MC340/TWIN double main shaft was 1994 the numerical control machine tool that imports from German STAMA company, because contingency discards as useless almost. We are repaired except the mechanical component to attaint outside recovering from an illness, still controlled a system to undertake type is designed updating to its, transform. 8 axle control of 1 CNCFormer the control of 8 axes controls a system formerly is Japanese FANUC-15M system, its CNC part controls two main shaft directly (an electromotor drive two main shaft, namely C axis) with X, Y, Z, A4 axis, the port that contains through PLC and STAMA company controls circumgyrate workbench (C2 axis) , knife library axis (Q axis) with manipulator of sharp campaign style axis (V axis) . PLC takes up I/O dot is nodded for 288/192 in all. C2 axis (circumgyrate type workbench) cent is two works area, while area of a work undertakes machining, another work area can assemble and unassemble workpiece, every loop can machine two works area give 8 work. Additional of primary machine tool change a knife to have its specialty, by Q axis (knife library axis) , V axis (straight formula manipulator axis) cooperate to complete the action that change a knife jointly with 3 axes such as Z axis. Its process is: When having the statement that change a knife, q axis turns to correct knife, v axis is taking manipulator to take a knife to knife library, move to be carried to main shaft again, of manipulator additional two knives that two claw hold main shaft to go up, unplug next through the motion on Z axial knife, manipulator is rotational after 180 ° , z axis drops to insert new knife main shaft again, v axis farewell will change the knife below to insert knife library former position to knife library. Change knife whole process to involve all sorts of actions of the motion of 3 axes and manipulator so, and many electromagnetism a powerful person and positional detecting element, whole act is more sophisticated.
Because FANUC-15M system is contraband to our country product,show the control of 8 axes, after classics survey is proved, we chose the system of SIEMENS-840D numerical control of four-axle linkage. Axis of main shaft and X, Y, Z, A is controlled by CNC directly, can reach original technical target completely. And axis of former PLC pilot C2, Q, V3, also instead CNC is controlled directly. As a result of chosen Xi Menzi the standard operates face plate not to take up exterior I/O is nodded, at the same time servo electromotor interior has appropriative position coder, managing many I/O dot, so PLC controls the I/O dot that take up to reduce 192/160 point. Realized the PLC function of primary machine tool, optimized PLC program, improved the function of primary machine tool. If specific means is undermentioned.If the controls axis of methodological former Q control block diagram of Q axis pursues 1. When CNC issues the statement that change a knife, send a number instruction and each control signal through PLC, adopt statement of imitate of interface circuit translate into, electromotor of drive of driver of repass Xi Menzi is rotational. Roll of synchronism of the library that follow a knife, and corresponding the absolutely coder ENC2 of 56 knives answers the thick position feedback of knife date PLC, achieve the goal of rough location, next again by accurate potentiometer: Will locate accurately, have the follow-up job that change a knife then. Mechanical drive catenary is here medium, two positions sensor all does not install above within electromotor. If sketch map of mechanical drive catenary pursues 2. Through drive of multistage gear and worm, worm wheel, electromotor and absolutely coder (the drive of ENC2) is compared for 157.357/1, and electromotor and accurate potentiometer (the drive of R) is compared for 2.81/1, all not be integer. Contain inside the servo electromotor with systematic form a complete set increment coder, but with will decide cutting tool position is improper, because its do not have one to one correspondence relation. Analysing whole knife library after main transfer machinery and coder character, we were used outside coder of buy increment type, install the position at potentiometer R, namely the drive of coder and knife library is compared for 56:1, can resemble axis of X, Y, Z, A so same, return referenced knife conveniently (it is) of a knife surely, and each knife have with coder again one to one correspondence relation, this kind of corresponding precision excels former accurate potentiometer because of the action of the 128 times frequency of CNC to locate again, achieved wide choice to locate thereby two kinds of purposes, realized the function of knife library axis. The control method of V axis controls block diagram to be similar to Q axle control to pursue formerly, just do not have potentiometer essence to locate. Buy of V position of axle by absolutely coder (ENC2) will detect. Axial control also uses V in transforming to be controlled by CNC directly. Because V axis hides within antrum of main shaft pillar, inconvenience returns reference point, must want to have positional memory, accordingly we chose the total travel that will enclothe V axis with the absolutely position coder of 840D form a complete set, the spirit that cooperates coder of buy of the set inside Xi Menzi electromotor to finish V axis jointly again is certain, achieved control precision is compared original tall.