Forming of simplified hydraulic circuits
The traditional technology of development of hydraulic circuits consists that the basic circuit all over again is created, and then problems of analysis (testing calculation) solve. For carrying out of calculation it is required to generate so-called simplified circuit containing only that information which is necessary. Therefore the simplified circuit of a hydraulic drive for carrying out of the analysis usually is a fragment of the basic hydraulic circuit. Hence, for carrying out of testing dynamic and static calculations from the basic hydraulic circuit it is necessary to take the certain fragments, to clean the minor hydraulic elements which are not playing an essential role in analysis problems, having left only those from them which are necessary also which are included into libraries of hydraulic elements for systems of dynamic and static calculation (so-called base functional hydraulic elements ). If thus it will appear, that any element of the circuit is not base, it is necessary to try to describe it by means combination of available base hydraulic elements (as a rule, it manages to be made rather easily).
Automation of these procedures at observance of such technology is provided with performance of the following stages of work:
1) Construction of the basic hydraulic circuit.
2) Stating positional designations in the circuit.
3) Extraction from the basic circuit of those its fragments which form the simplified circuit (or some simplified circuits).
4) Forming of the simplified circuit in the kind of separate drawing.
5) Drawing on the simplified circuit of nodes, their numbering and preparation of file of the structure description according to algorithms of dynamic and static calculation.
The first stage is in detail described above in the same paragraph. As to stating positional designations they are some kind of the identifiers providing an exchange, choice and transfer of the necessary information between various components of system of computer-aided design of hydraulic drives (construction of the basic circuit, design calculation, information retrieval system (database), testing calculations, drawing up of the specification, etc.).
The kind and content of the simplified circuit , structure of elements entering into it are defined by developer only. At forming of the simplified hydraulic circuit the following requirements should be executed:
1) Simplified circuit should contain only base functional hydraulic elements from libraries of dynamic and static analysis.
2) On the circuit points of crossing of 4 and more pipelines should not be (otherwise it is necessary to make a corresponding outcome of such nodes by means of tees ).
3) For convenience of stating and subsequent numbering of nodes free placement of symbols of hydraulic elements on the circuit is desirable.
Construction of the simplified circuit comes to the end with replacement of all crossings of pipelines of a kind "tee" by corresponding symbol from library of standard graphic symbols . Thus the point on place of crossing of pipelines automatically leaves from the circuit.
Upon termination of transformation of the basic circuit in simplified circuit and its forming as drawing there comes the last, fifth stage – drawing on the circuit of nodes, their numbering and forming of file of the circuit structure description. The special algorithm providing preparation of the structure description of the circuit for the solution of problems of design calculation and analysis is developed for this purpose. All cycle of work of algorithm shares on four stages.
1. Search of symbols of hydraulic elements on the circuit according to rules of the structure description of hydraulic circuits . If on the circuit there was a directional control valve, the algorithm passes in dialog (interactive) mode, requesting, what position of a spool is neutral and what – the worker. The answer of the user serves as the additional information on a direction of working liquid flows through the directional control valve.
2. Search of the circuit pipelines. Thus communications between separate sites of pipelines are established and so it is found out, what of the circuit nodes are connected among themselves by pipelines. In the end of this stage there is a numbering of the circuit nodes.
3. Definition of directions of liquid flows in separate sites of the of a liquid (at working positions of spools of directional control valves). First the algorithm works in an independent mode, trying "independently" to define directions of working liquid flows and if it is not possible, passes in an interactive mode, requesting, what direction of flow between nodes should be given.
4. Forming of file of the circuit structure description.
After end of work of the algorithm it is possible to receive a firm copy of the simplified hydraulic circuit for carrying out of the further work.
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