【机械专业英文文献】可编程控制器设计的气动系统

附件2：外文原文Programmable Controller Designed forElectro-pneumatic SystemsSummary this item is mainly the procedure which studies electricity system and in brief valid control current of air to launch machine to compatibly flow the appearance of system. It of the fulfillment foundation include according to the control procedure of particularly have of the current of air controller, automation design, current of air system and design according to the electronics of the tiny controller.1. Brief introductionThe automation which uses an electricity technique mainly constitutes to. from 3 part: Launch machine or motor, sensor or button, the form is zero partses such as the control of flower petal. Now, greatly part of system logic the controllers of the operation drive all procedure logic controller (PLC) replace. PLC sensor and switch's aring an importation to carry, but launch the direct control valve of machine is an exportation to carry and have an internal procedure to operate among them all circulate essential logic, imitate other devices like calculator, in fixed time machine etc., carry on a control to the whole movement appearance of system.Can according to need numerous time to establish and imitate thus of system, so all from PLC usage, this item contains vivid advantage. Therefore can save time, the danger of decrease error, in the meantime under the sistuation that use same material, it can be getting more precise.Many company that is on the market used the PLC of normal regulations and it can not only control with the current of air system, but also can use various electricity equipments. PLC wide range of application, can be apply in much industry to produce medium, even used for safety and automation of building in.Because of above various characteristic, the PLC provided a lot of resourceses in somely physically appliedly, even include not a resources of control the system and the electricity system was a kind of application like this.For the engineering of automation, the PLC usage is more expensive, particularlyis to those small scaled systems.Aim at this kind of circumstance's a kind of viable way establish a controller that can provide particular size and function. This kind of controller can create according to the tiny controller.This kind of applies scope according to the tiny controller smaller, the machine that can used for a type perhaps can use to do a be like the common PLC is similar and can be woven a distance of controller, so it can pass variable turn of logic procedure to carry on various homework. All of these characteristic basis concrete demand of dissimilarity but dissimilarity, concrete of design of empirical of dissimilarity but dissimilarity. But the main advantage of this kind of design lie in designing a personnel to understand an own controller very much, can freely control the big baby size of controller, change it of function. This means that this item contains more special, but in the meantime the control of system also from it of design control.2. Electricity systemPeople can find out to speak of in three preceding contexts from an automation of basic parts, the in addition is a logic circuit which controls system. The technique of only mature forerunner cans make a particular logic circuit and performance the parts that exactitude need when operate to get stripe. For a simple sport, the system auto procedure can complete, but for indirect or more complicated sport, the procedure of system will produce complicated circuit and false signal. This is need another method can save time, produce clear circuit, can keep accidental signal from hand over fold to stop with circuit.The line roadbed method of different standard of this kind of way call follow the sequence and advance gradually type or rule system, it to the current of air and the electricity system very valid, and is also a foundation of this item. It include according to launch the system of foundation that the machine appearance each dissimilarity variety establish.The square one is each circuit that the step designs those kinds of standards. The second step is a conjunction to receive to come from sensor and the switch sends the air or the fax to the supply line of each step in the meantime with previous sport signal. If show in the diagram, 1 with 2 standard circuits is a current of air of with the electricity system serve. We can know very much of see each one step suddenly with the contact of the of next step.3. The applied principle of controller inner partThe above-mentioned method can make each sport of launch the machine nicely defined with the step. This be also a new appearance which says that the every sport varieties of launch the machines are systems, but the change of of two different appearances be called a step.The standard circuit which speaks of in times before can the in aid of design personnel define different appearance different from what the variety of different step bring environment of system. The end stage in design will have a sequence and explicit input and output which never changes tocarry in the system. We carry a sequence is from the importation the importation be through conversion carried exportation by the exportation.All processes of these steps carry on in the tiny controller inner part, and with same of the way is circulate. The sequence of parts is program by 5 bytes in the controller; Each part contains a step structure of procedure. The importation carries two bytes, the exportation carries 1, and part of and additional function steps of other structure contain 2.After weave distance, the parts sequence is store by the remember of internal and tiny controller, therefore, they are readable and can circulate.Differ from traditional PLC, the work purpose of this kind of controller is to become particular realm to design of use controller more. The system of traditional PLC's circulating procedure is a circuit of circulation: Input a picture, circulate all internal procedures, then get stripe output's appearance. This controller work in different way, it read the structure of step, wait for an importation, then get stripe or output, then directly jump up next step, start another procedure movement.It has already limitted sex as well, for example this kind of controller sometimes doesn't carry out instruction, will appear a certain movement again and again an etc. under same procedure instruction, but this problem can resolve through an exterior logic movement. Moreover, this win the controller is have no sequence of the system top can't be apply enough. These limit sex is also this system of characteristic, each applications of this kind of system have to include homologous system analysis.4. The special features of the controllerThis kind of controller takes tiny tiny controller PIC16 F877 of the integrated circuit as foundation and it owns all the resources need by this subitem. It has an enough socket and the circuit continuous communication EEPROM memory gives relief to all structure of the system and the sequence of the step. It provided the movement of havings need by item, for example in fixed time machine with diverge etc..We did the resources catalogue of controller, want to make it change possibly of perfect. In the movement process of step, the procedure automatically chooses how to read an each one step suddenly of structure. This operation has two bytes to be located on an electronics importation. A byte is also located on exportation to carry, have 1 to be used to inner part in fixed time a machine, similar input or pause function. The EEPROM memory inner part is 256 bytes, can store all movements of steps, then with all movements of which stores 48 steps.In addition to an interactive menu, this kind of controller still has a control set and some instruction topress button and they control the movement of each step together with continuous and also control a little bit other devices.4.1 hand over with each other a functionAt actual circulate in operation, the controller needs some assistance equipmentses to help it and the user carry on interaction, can provide dependable of operation supervision, carry on a logic control to the current of air system in the meantime.Hand over to with each other work mode: In the main procedure, the user can send out signal to carry on the operation of concrete step according to the instructionThe LCD terrace can show the appearance of system work, measure an importation, output, timer and circulate of data etc..The voice of Di Di is use to hint important caution, stop, the take place of beginning and some urgent circumstances bright light means to connect power supply, with importation, output appearance.4.2 safetiesIf want to normally circulate procedure, have to promise each performance with all correct step. More important, should there is prevention circulating to break down and problem of resolve a method. The controller provided this kind of possibility and passed to use two internal and virtual circuits to circulate in the meantime. They can re- start procedure and recover the original appearance of procedure at any time. There are two importations carrying a common work can quickly circulate these functions.4.3 connectThe procedure movement sequence can use connect of controller to weave a distance. A set calculator connects and can also use to get stripe usage procedure. The user can make use of to connect to install a series of steps bytes which define a sequence. But can also design a procedure, the exploitation can treat resources as the information that user need when translate. But, if want combining a computer connects and controller, should have an instrument to the credibility of the assurance data at least. 4.4. FirmwareMain line wreath is pass to read EEPROM memory in of each information step carry on a work.In each step, the appearance of system is store and it also is show on the display in the meantime. According to the structure of user, it can make use of reposition of redundant personnel or pause to cope with an urgent circuit circumstance to promise a system safety.5. Electricity system exampleThis kind of system is much more than an orientation at the particular machine. It constitutes to°from four active machines. The active machine A, B and C are double and only the D be doubly a list. Square one, the active machine A starts circulate, and keep in a particular position until a be over of circulation, such as figure 5 show it can make sure some one object of under one sport. The second step, was A to complete it of work after, the active machine C is together with the B start together many creation electric current a turn possibly, and be subjected to the restriction of B movement speed, but the B speed be lived a petal management by a control of fluxion. B and C is work together of active machine of example, be the B slowly pushes an object of time, the C sometimes then repeats it of work.The third step, be the position time that the B arrives an end, the C is immediately stop it of the circulation exercise and return to the position of beginning. The active machine D that the electric current that the exploitation return work together with return of the C works together. The fourth step, the active machine D quickly goes back and forth a return to exercise once. The D can act as a tool, the superficial dozen that is on the object hole. When the D returns to the position time of beginning, AN and B also return in the meantime and this be the fifth step.Diagram 6 showed program design the first part. We know together as all movements of each step. (A+) mean that the active machine A pushes forward, but(A-) means to return to the position of beginning. Sport of the simultaneous with is together fold to add in the same step. This system totally has five steps.Diagram 5 circulate with 6 systems for express clear of described all sequences. Make use of them, we can design with the essential logic language whole of control circuit. But now return it not just an integrity of system, because it is still in need of some assistance facilities, .(diagram in show) Circulate to the end of procedure, these assistance facilitieses are very important, because they can make the circuit have more functions. They win the most important is a conjunction in eachly the one step suddenly of parallel circuit. That circuit can stop a sequence and change the appearance of active machine into a particular position at any time. It can heavy system or cope with an urgent circumstance. Diagram 7 with 8 what to shows be some results that will take place under the sistuation that have no usage controller. These photographs are the electricity charts which controls circuit, include sensor, control key and give or get an electric shock of live petal book.Moreover some assistance facilities also include in this system, the for example automatic machine/ hand moves to adjust to control a machine, they can make system continuous of circulating work; Two beginning control keys, they can let the operator hand move a beginning of control the system with stop, so reduced to take place an accident of danger.6. The user changes an example programmingCurrent of air coil fore the noodles has already elaborated on: It can let us understand to control the condition that a system need and that is in the actual movement in system and have to provide all function facilities. But, such as before speak of of so, use a PLC or particular controller, this kind of control becomes more easy of, and the nicety of the system will also raise.The usage traditional PLC of, such as figure 7, 8 show, notice while draw electricity chart of connect the logic of circuit. The usage is this kind of programmable controller and the user needs to know to circulate the idea of the method and the structure of the programming each step.That is to say, use traditional PLC, the user knows the relation of of each operation. Under the general circumstance,User can before connecting a people's top to circulate 1 to imitate procedure to look for a logical mistake together say of similar, new of plait the distance allow an each one step suddenly of the structure be partition. The sequence is alone define, but each one step suddenly be carry by the input and output to describe.7. ConclusionThis kind of controller's ising specialized is what this item design. Showed 1 takes tiny controller as the programmable controller of basal great use. It doesn't need for obtaining the resources in the tiny controller but installing exterior memory a machine or exterior in fixed time a machine. In addition to tiny controller outside, only have a little amount of zero parts performance some like output, importation, type ratio importation, show a circumstance of connect the and continuous movement etc. function.Use inner part memory alone, we can control a current of air system which has 48 steps, but if use a more simple system, will attain 60 steps. The controller becomes not to use PLC language, but use one more simple of with intuition of structure. Make use of electricity system, our items applied a same technique, but our designs be getting more direct in the meantime.A kind of very simple machine language can the one who let design use 4 or 5 byte definition a step all structure composing. This will see how experience that he use controller is .Although this kind of controller can't compare with the PLC of business, it is originally particular of of purpose but design of, so hard to say which good which bad. In fine, our this systems are in brief fast according to tiny controller but design.。