[Summary] the article introduced new-style but controller of process designing computer (PCC) the working principle that much task handles and the application in noting model machine to control a system, gave out to note what model machine PCC controls a system to form with task set, rose effectively to note the integral performance of model machine. [Crux word] but controller of process designing computer (PCC) ; Record model machine; Much task handles forming machine of introductive and contemporary plastic inject, abbreviation records model machine, it is opportunity of a market, report, fluid the typical system at an organic whole, can shape because of be being had sophisticated products, hind the plastic sort that treatment measures little, treatment is much wait for a characteristic, since come out, development is very rapid, already made the main equipment of plastic processing at present. But the process that because note model procedure,is constant temperature of stability of a blame, blame, adding up to model, inject, litre (fall) lukewarm the quality that the craft parameter in waiting for each to produce a course will affect plastic products directly, to noting the control of model machine consequently the system raised very tall requirement. Must have perfect automation control and regulating system, those who assure pair of opportunity that note model is controlled measure has the reliable control that repeats precision and sensitivity certainly and adjust. Already had a lot of manufacturer at present will but program controller (abbreviation PLC) use at noting model machine to control, but traditional PLC is only job model, only to the program using for the system, si is competent very hard the control requirement of real time system. In recent years, those who have much task to handle a function is new-style but controller of process designing computer (abbreviation PCC) it is the new generation PLC that development rises, it applies to miniature control not only, can be competent more complex, tall to requirement of real time sex control circumstance, and its trend is the system is had but expansibility, also increasing ceaselessly to the support of spot bus line and network. The principle of much job job that accordingly we study PCC, use its at be opposite to note the control of model machine, to plastic product quality and economic benefits rise, have economic value. One, the PLC that the much task of PCC handles principle only job to control fashion appears not quite agile when handling a few complex tasks, insufficient even, the PCC that has operating system of much task time-sharing is a kind of controller that suits relatively. If the structural model of the PCC that has much task to handle ability pursues 1 is shown, operating system kernel is the standard operating system that has much task capacity, it can fulfil the basiccest function such as the processing between much task and applied process management. Intermediate layer is the special software package of PCC, basically manage by task of systematic government, system, standard task, the composition such as software of management of high speed task, communication, it can control much task to handle the execution of ability, implementation presses each task to carry out order to undertake calling to different task level, surveillant the cycle time of each job layer, setting, control and compulsive processing the function such as I/O of every job layer and communication processing. Outer it is applied process, each applied processes (call the job again) can move at the same time in PCC, the ability of processor is passed " job switch " in allocating many application process. The first step that model of structure of graph 1 PCC differs to make many PCC task is had, the user can be task setting in different task level, the user also can give every task grade to set different cycle time, inside the cycle time of the setting, corresponding task is carried out. If set the periodic time of some task to be 50ms, criterion every 50ms implements the system the task module of this level. In PCC software system, allow an user to use two kinds of different job layers, standard job layer (TaskClass) with layer of high speed job (HS – TaskClass) . The cycle time that basis of standard job layer can set can be divided again for 4 jobs layer, namely TC#1 ～ TC#4. Layer of high speed job also is divided for HS#1 ～ HS#4 layer of job of 4 high speed. Executive first step presses TC#4 of ～ of HS#1 ～ HS#4-TC#1 ordinal and degressive. Use a program is the set principle of level of each task module: ? Stool of calumnying Kang kills Shan breaking to suckle Qiong ? to should reduce its level as far as possible, in order to avoid CPU overload. Is the each task module that uses a program spent to the load of CPU press type is calculated: ? The: in 100% type of?Ti/Tt × ? ? this task is spent to the load of CPU; The actual run time of Ti- this task (Ms) , can determine by Profiler software; Tt- this task is located the cycle of level (Ms) . Move to make sure CPU is reliable, the λ of each task should not exceed 80% . Now with TC#1 and TC#2 the executive circumstance of two tasks level is exemple (show 2 times like the graph) , handling a process is to execute the mission with high level first actually, if TC#1 actual run time is 4ms, after TC#1 is carried out, carry out TC#2 again, because the run time of TC#2 is 9ms, beginning to carry out TC#1 to arrive to be carried out the next time (namely periodic 10ms) when, TC#2 has not moved, because the preferential level of TC#1 is high, so the execution of TC#2 is interrupted, and turn go carrying out TC#1, wait after carrying out TC#1, turn again go carrying out TC#2. Graph 2 in ① expresses operating system clock, ② states what systematic government needs time, ③ is the executive sequential of TC#1, ④ is the executive sequential of TC#2. Systematic government time is used at the management to systematic task, this time is unalterable, carry out for cycle with the operating system clock of 10ms. Graph the application of the executive circumstance nextpage2 of 2 two tasks, PCC in the machine that note model 2.
PCC of the 1 machine that note model controls systematic composition to note model machine to control a system is a basis its job principle, according to the technological process that note model, control and carry out the control of the component what infect feeling cell each to recording model machine scene through PCC to concerning, implementation is plastic to differring shape in inject the automata of each craft in the process and be monitored automatically and protect. Control system chooses automation of Bei Jialai industry (Shanghai) the B&R2005 in the 2000 series product of the company, it is a kind compact model product, its structure uses module formula, all module size is same, can pass set combination freely to insert neatly unplug will expand system. Specific chosen module has: CPU is CPU152, applied memory is ME963, power source module is PS792, digital amount inputs module to be DI477, digital amount outputs module to be DO480, imitate quantity inputs module to be AI775, temperature inputs module to be AT350, imitate quantity outputs module to be AO775, LCD shows module is DI164 and substrate to wait. The compositive block diagram of system of PCC whole control is shown 3 times like the graph. The compositive control of system of control of graph 3 PCC sets air standard, hand to move in the system note model, semi-automatic note model and full automatic note model way of a few kinds of works. The I/O interface circuit that working way chooses to pass PCC by rotary switch is deferent to the system. There is 20 in the system many journeys switch, journey switch uses suddenly Er cell, its advantage dispute contacts electromagnetism induction, adjust convenient and reliable. These travel information also are the I/O interface circuit that passes PCC through keeping apart report deferent to the system. There are 17 electro-magnets in the system, dominate the different action that note model respectively. The controls signal classics PCC I/O interface of output and the electrify that keep apart circuit to control 17 electro-magnet and cut off the power. 2.
System of 2PCC pilot software and the software that task set PCC controls a system use module program structure, block diagram of its program structure sees a picture 4. Graph the affirmatory principle that block diagram of structure of program of system of control of PCC of the 4 machine that note model creates principle and each job cycle time according to the level of task module, carry out a circumstance actually what consider each module, outside dividing man-machine interaction module and systematic initialization module, the cycle time of the choice of each task level and each task sees next tables. Specific the control program of each module can ask according to controlling signal flow, control and realize a method to use PLC2000 advanced language or echelon graph will weave. Task information is expressed 2.
The problem that the attention answers when 3 tasks set 1) when the capacity that designing total system, put apart the capacity of 10% is used for the operating system; 2) when planning task level, this system asks real time sex to tall task is put in high level, execute circular number namely much; 3) when the task is installed, also be put apart of blame loop task enough time, in order to make sure the processing time of this kind of task is enough; 4) in moving actually, as a result of the condition with the moving certain need of each program module, so the moving hour of much task always is not a constant; 5) to increase the processing capacity of real time much task, PCC can use dual structure on hardware, one is in charge of with the input / the communication that outputs module, another CPU is used technically at handling user order. 3, the treatment procedure that the last word notes model machine to controlling systematic response speed raised taller requirement. The PCC that collects appliance to much task handles ability undertakes controlling to the system, reasonable set the task level of each task module, the respect such as quality of efficiency of the performance that noting model machine, production, treatment had relatively substantially rise. In applying actually, much task handles ability more and more show its advantage. CNC Milling