Drawings ofConditions of successful mastering technical knowledge are ability to read drawings and knowledge of rules of their performance. The drawing is one of the main carriers of technical information without which any production does not do. At present it is impossible to imagine work and development of a large number of branches of a national economy, and also science and equipment without drawings. On again created devices, cars and constructions at first develop drawings. Determine their merits and demerits by them, do changes in a design. Only after discussion of drawings make product samples. Engineers, workers and technicians have to be able to read the drawing to understand both a design, and work of the outlined product, and also to state the technical thoughts, applying the drawing. Drawings are widely applied also in educational institutions when studying all-technical, theoretical and special objects. Drawing - one of the main objects which teaches performance and reading drawings.
The technical graphics began to develop very long ago, approximately in the middle of the 17th century, and some drawings and drawings which reached up to now confirm high art of their performance. Since the beginning of the 18th century. Technical drawing gives way to the drawing more and more. Already in that the moment drawings enough difficult products and constructions were required, and for implementation of such drawings special preparation was necessary. All objects surrounding us (for example, machines, devices, automatic machines, buildings or their parts) can be represented as they are presented to our eye, - by means of drawings or photos. In equipment other way of their image - in the form of drawings is accepted. The subject is transferred on the drawing seen from various parties. It allows to present a form of a subject on the drawing and to specify all sizes necessary for its production. Difference of the drawing from drawing and the photo consists in what on the drawing objects transfer by special rules. Drawing of a subject shows its height, length and width as sees drawing it, i.e. one image.
However in drawing separate parts of a subject are represented with which - what distortion. For example, cylindrical openings are shown in drawing in the form of oval, right angles - in the form of stupid and sharp, and rectangular surfaces - in the form of parallelograms. The same shortcomings also the photo possesses. As a result of the distorted transfer of forms and the sizes of objects in drawings and photos use them in equipment only as supportive applications of the image. On the drawing the figure of a subject is shown, as a rule, several images.
Any construction and any production - from the ordinary handle to the modern plane - is impossible without preliminary development of the drawing.