With PLC control pace submits the principle of electric machinery and method

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1, the overview is in transfer matic of modular machine tool, ask to install 3 kinds of slip according to different treatment precision commonly (1) hydraulic pressure slip, use at cutting the amount is large, treatment precision asks inferior rough machining working procedure is medium; (2) mechanical slip, use in cutting quantity to wait, in having the semifinishing machining process that machines precision requirement certainly; (3) numerical control slip, use at cutting the amount is small, treatment precision asks very tall finish machining working procedure is medium. Can make up Cheng controller (abbreviation PLC) with its versatility strong, dependability system of tall, instruction simple, process designing is handy learn easily, master easily, bulk small, maintenance works installation of interface of little, spot is convenient wait for a series of advantages, be applied extensively in industrial automata. Especially in modular machine tool function of the S of the control of automatic product line and CNC machine tool, T, M is controlled more show its outstanding performance. PLC pilot pace applies at modular machine tool into orgnaization of servo of electric machinery open loop the control of numerical control slip on automatic product line, but the control system cost that this unit numerical control system makes this unit reduces leave out 70~90% , the 3~5 that takes up transfer matic controls unit PLC only even the memory of I/O interface and <1KB. The cost that can make control a system in large transfer matic especially drops significantly. 2, the numerical control slip in transfer matic of common modular machine tool uses structure of slip of PLC pilot numerical control the orgnaization of open loop servo that the pace takes electric machinery drive. Use slip of PLC pilot numerical control by can make up alloter of pulse of Cheng controller, round, pace to enter the part such as electric machinery and servo main transfer machinery to comprise into electric machinery driver, pace, the gear Z1 in servo main transfer machinery, Z2 should take disappear unoccupied place step, avoid to produce retrorse dead band or make machine precision to drop; And guide screw drive deputy should machine precision requirement unitly according to this, whether to choose ball guide screw certainly deputy. Use ball guide screw deputy, have transmission efficiency stiffness of tall, system the good point that tall, service life grows precision of good, drive, but cost is higher and cannot lock up oneself. 3, the control element of the slip of numerical control of PLC control method of numerical control slip basically has 3: 3.

The journey control that 1 journey controls slip of general hydraulic pressure and mechanical slip is to use the position or pressure sensor (journey switch / block iron to death) will come true; And the journey of numerical control slip uses digital control to come true. By the structure of numerical control slip knowable, the journey direct ratio of slip takes the total corner of electric machinery at the pace, the total corner that because this wants control condition only,takes electric machinery can. The total corner direct ratio that enters the working principle of electric machinery and characteristic and knowable pace to enter electric machinery by the pace controls pulse at what what input several; The pulse that because this is OK,decides PLC output according to the displacement quantity of servo orgnaization several: N=DL/d (1) the DL in 　 type -- the displacement of servo orgnaization is measured (Mm) 　 　 D -- the pulse equivalent of servo orgnaization (Mm/ pulse) 　 　 3.

The feed speed of orgnaization of servo of control of 2 feed speed depends on the rotate speed that the pace takes electric machinery, and the pace depends on into the rotate speed of electric machinery the pulse frequency; of the input because the feed speed that this can ask according to this working procedure, decide the pulse frequency: that its PLC outputs? The Vf in type of  =Vf/60d(Hz)(2) 　 -- the feed speed of servo orgnaization (Mm/min)nextpage3.

Direction of feed of control of 3 feed direction is controlled namely the pace enters electric machinery turn to control. The pace enters electric machinery it is OK to change direction through changing a pace to enter electric machinery the electrify order of each winding changes his to if three-phase pace enters order of electric machinery electrify to be A-AB-B-BC-C-CA-A,turn to; ... when the situation is turning into electric machinery; presses A-AC-C-CB-B-BA-A when winding... the pace when ordinal electrify inverts into electric machinery. The output that because this can pass the way that PLC exports control signal,changes hardware round alloter comes true orderly, or the electrify order that the order that outputs pulse via process designing change will come to to change a pace to enter electric machinery winding comes true. The software control of 4PLC controls a method by the PLC of slip logically knowable, the input pulse gross that should make the pace enters electric machinery and pulse frequency are controlled accordingly. The pulse signal generator that because this is controlling the setting on software,gross of a pulse and pulse frequency can accuse; To the control pulse with inferior frequency, the timer in can using PLC is formed, if pursue,2 are shown. Pulse frequency can pass the time constant of timer to control pulse cycle, pulse gross control can install C10 of one pulse tally. When pulse number achieves set to be worth, tally C10 movement cuts off pulse generator loop, make its quit the job. Movement quits when the pace of servo orgnaization is inputted without pulse into electric machinery, servo actuator locates. When the displacement speed demand when servo actuator is higher, can use the generator of high speed pulse in PLC. The frequency of pulse of its high speed can amount to different PLC 4000~6000Hz. To the general servo orgnaization on transfer matic, its speed can get be satisfactioned adequately. 5, servo control, drive and interface 　 5.

The control system that 1 pace controls compositive pace of the system to enter electric machinery into electric machinery by can make up alloter of pulse of Cheng controller, round and pace to enter driver of electric machinery power to comprise, the PLC in controlling a system uses generation to control pulse; Output a certain quantity of square wave pulse through PLC process designing, control pace controls the feed of servo orgnaization then into the corner of electric machinery; Control pulse frequency through process designing at the same time -- already the feed speed of servo orgnaization; The electrify order that round pulse alloter receives the control pulse that can make up Cheng controller to output electric machinery by the pace allocates corresponding winding. PLC pilot pace can use software round alloter into electric machinery, the hardware round alloter that if the graph is shown 1 times,also can use. The PLC resource that uses weak link to take up is more, especially when the pace counts M>4 into photograph of electric machinery winding, should give to large product line mature. Use hardware round alloter, although hardware structure a little some more complex, but OK and economic take up the I/O opening check the number of PLC, at present the market has a variety of special chip to be able to be chosen. The control pulse that the pace outputs PLC into driver of electric machinery power magnifies about a hundred volt of a few ~ , a few install ~ ten installed drive capacity. The output interface of general PLC has certain drive capacity, and normally the laden ability of interface of transistor dc output is ten ~ only a few volt, a few ~ hundreds of milliampere. But ask into electric machinery to power pace about a hundred volt of a few ~ , a few install ~ ten installed drive capacity, because this should introduce drive,undertake enlarge to outputting pulse. 5.

The 2 interface that can make up Cheng controller use hardware round alloter like servo orgnaization, take up the I/O opening check the number of PLC is little at 5 o'clock, it is only commonly at 3 o'clock. Among them I mouth takes up a bit, regard the control that start as signal; O mouth takes up at 2 o'clock, the pulse that served as PLC outputs interface, receive the clock pulse to servo strong link to input end, change control to at another o'clock signal into electric machinery as the pace, receive the appearance sequence to strong link to allocate control end, if the graph is shown 3 times; When servo uses software round alloter, 6, applied example and conclusion use orgnaization of servo of PLC pilot open loop at some numerical control slip of large product line, every slip takes up only 4 I/O interface, saved CNC to control a system, its pulse equivalent is 0.

01~0.

05mm, feed speed is Vf=3~15m/min, completely contented craft asks and machine precision to ask CNC Milling CNC Machining