What determines the number of views in the drawing? Location of main views in the drawing. Conventions and simplifications
The rules for depicting products on drawings of all industries and construction are established by GOST 2.305-2008. Images of objects are made using the rectangular projection method. In this case, the object is placed between the observer and the corresponding projection plane (Fig. 15). The main projection planes are the six faces of the cube onto which the object is projected; the edges are combined with the plane, as shown in the figure.
The images in the drawing, depending on their content, are divided into kinds,cuts And sections.
The number of images (types, sections, sections) should be the smallest, but providing a complete picture of the subject when using the symbols, signs and inscriptions established in the relevant standards.
8.1. Kinds
View is an orthogonal projection of the visible part of the surface of an object facing the observer.
Types are divided into basic, additional and local.
Main types– views obtained on the main projection planes (cube faces). The standard establishes the following names of the main types (Fig. 16):
1 – front view (main view);
2 – top view;
3 – left view;
4 – right view;
5 – bottom view;
6 – rear view.
Rice. 16. Main types
If the arrangement of views in the drawing corresponds to Fig. 16, then the names of the types in the drawing are not signed. Main view of the item (main view) - the main view of an object on the frontal projection plane, which gives the most complete idea of the shape and size of the object, relative to which the other main views are located. If the views from above, left, right, below, behind are not in projection connection with the main image, then they are marked on the drawing as ""А"" (Fig. 17).
Rice. 17. Designation of a view located outside the projection connection
The direction of view is indicated by an arrow, indicated by a capital letter of the Russian alphabet, starting with the letter À. Drawings are also drawn up if the view is separated from the main image by other images (Fig. 18) or is not located on the same sheet with the main image.
Rice. 18. Identification of a view separated by another image
The font size of the letter designations is approximately twice the size of the digits of the dimension numbers. The arrows indicating the direction of view should be the same in shape as the dimensional ones, but larger, with a thickened linear part.
Additional views– images on planes not parallel to the main projection planes. They are used in cases where any part of an object cannot be shown in the main views without distorting its shape and size.
An additional view is marked on the drawing with an inscription like ““А””, and the image of the object associated with it should have an arrow indicating the direction of view, with a corresponding letter designation (Fig. 19).
Rice. 19. Location of additional views
The additional view can be rotated relative to the specified viewing direction, while maintaining the position taken for a given object in the main image. In this case, the sign “” is added to the inscription ““А” (Fig. 19), replacing the word ““rotated””.
The dimensions of the arrows indicating the direction of view and the sign are shown in Fig. 20.
Rice. 20. Arrows for additional and rotated views
When an additional view is located in direct projection connection with the corresponding image, the arrow and view designation are not applied.
Local view– an image of a separate limited area of the surface of an object on one of the main projection planes (Fig. 21).
Rice. 21. Image and designation of a local species
The local view may be limited to the cliff line, as small as possible, or not limited. The detail view should be marked on the drawing like the supplementary view.
Basic, additional and local views are used to depict the shape of the external surfaces of an object. Revealing the shape of the internal surfaces of an object with dashed lines makes it much more difficult to read the drawing and complicates drawing dimensions. Therefore, to identify the internal (invisible) configuration of an object, they use cuts and sections.
The rules for depicting objects (products, structures and their components) on drawings of all industries and construction are established GOST 2.305 - 68.
Images of objects should be made using the method of rectangular (orthogonal) projection onto a plane. In this case, the object is placed between the observer and the corresponding projection plane. Attention should be paid to the difference that exists between the image and the projection of an object. Not every image is a projection of an object. There is a one-to-one point correspondence between an object and its projection, which consists in the fact that each point of the object corresponds to a certain point on the projection and vice versa.
When constructing images of objects, the standard allows the use of conventions and simplifications, as a result of which the specified compliance is violated. Therefore, the figures obtained when projecting an object are called not projections, but images. The faces of a hollow cube are taken as the main projection planes, into which an object is mentally placed and projected onto the inner surfaces of the faces. The faces are aligned with the plane, as shown in Fig. 1.
Rice. 1 Types
The image on the frontal plane is taken as the main one in the drawing. The object is positioned relative to the frontal projection plane so that the image on it gives the most complete idea of the shape and size of the object. The images in the drawing, depending on their content, are divided into types, sections, sections.
View - an image of the visible part of the surface of an object facing the observer. To reduce the number of images, it is allowed to show the necessary invisible parts of the surface in views using dashed lines. However, it should be borne in mind that the presence of a large number of dashed lines makes the drawing difficult to read, so their use should be limited.
Types are divided into basic, local and additional.
Main types- images obtained on the main projection planes - the faces of the cube (Fig. 1):
1 - front view (main view);
2 - top view;
3 - left view;
4 - right view;
5 - bottom view;
6 - rear view.
The names of the views are not inscribed on the drawings if they are located as shown in Fig. 1, i.e. in projection connection. If the views from above, to the left and to the right are not in projection connection with the main image, then they are marked on the drawing with an inscription of type “A”. The direction of view is indicated by an arrow, indicated by a capital letter of the Russian alphabet.
When there is no image that can show the direction of view, the name of the species is inscribed.
Local view is an image of a separate limited area of the surface of an object on one of the main projection planes. The local view can be placed on any free space in the drawing, marked with an inscription like “A”, and the associated image of the object should have an arrow indicating the direction of view, with the corresponding letter designation (Fig. 2).
Rice. 2. Additional and local types.
The native species may be limited to the cliff line, as small as possible, or not (Fig. 2).
Additional views- images obtained on planes not parallel to the main projection planes. They are used in cases where any part of an object cannot be shown in the main views without distorting its shape and size. An additional view is marked on the drawing with an inscription of type “A” (Fig. 2), and an arrow with the corresponding letter designation is placed at the image of an object associated with the additional view (arrow A, Fig. 2), indicating the direction of view.
When an additional view is located in direct projection connection with the corresponding image, the arrow and inscription above the view are not applied (Fig. 2). The secondary view can be rotated while maintaining the same position as the item in the main image. In this case, the sign “rotated” is added to the inscription “A” (Fig. 2).
Basic, local and additional views are used to depict the shape of the external surfaces of an object. A successful combination of them allows you to avoid dashed lines or reduce their number to a minimum.
(SITELINK-S35)back (/SITELINK)
5.1. View placement rules. To fully identify the shape of objects in drawing, various images are used: views, sections, sections. First you will study the species.
View- This is an image of the visible part of the surface of an object facing the observer. To reduce the number of images, it is allowed to show in views the necessary invisible parts of the surface of an object using dashed lines. And Difference from projections in views, some conventions and simplifications are used. You will study them later.
The image obtained on the frontal plane of projections is called front view. This image is taken in the drawing as The main thing. Therefore, this type is also called the main one. When making a drawing, the object must be positioned in such a way relative to the frontal plane of projections that the main view gives the most complete idea of the shape and size of the object.
The image on the horizontal projection plane is called top view.
The image on the profile plane of projections is called left view.
Along with front, top and left views, right, bottom, and rear views can be used to depict an object (all of them are called main). However, the number of views in the drawing should be the smallest, but sufficient to fully identify the shape and size of the object. To reduce the number of views on them, it is allowed to show, if necessary, invisible parts of the surface of the object with dashed lines. For the same purpose, various symbols, signs and inscriptions established by the standard are used.
Rice. 52. Three types of parts
Figure 52 shows three views of the part, a visual representation of which is shown in Figure 53. The main view is the front view. Below it is a top view, to the right of the main view and at the same height - a view to the left. The cutout in the rectangular part was invisible in the top view, so it is shown with a dashed line.
Rice. 53. Visual representation of the part
5.2. Local species. In some cases, instead of the full view, you can use part of it in the drawing. This simplifies the construction of an image of an object.
The image of a separate, limited place on the surface of an object is called local species. It is used in that case. when you need to show the shape and dimensions of individual elements of a part (flange, keyway, etc.).
The local view can be limited by a cliff line, an axis of symmetry, etc. It can be marked on the drawing and with an inscription. The local view is placed on a free field of the drawing or in projection connection with other images. At school you will consider local species located only in projection connection (Fig. 54).
Rice. 54. Local views located in projection connection
The use of a local type allows you to reduce the volume graphic work, save space on the drawing field.
- Define the species.
- How are the views arranged in the drawing?
- Which species is called the main one and why?
- Which species is called local? For what purpose is it used? What are the benefits of using a local species?
Rice. 56. Exercise task
Redraw in workbook data in Figure 56, and drawings and supplement them with the image of the second box.
Directions for use. If you find it difficult to solve the problem, make models from boxes, as shown in Figure 56, and compare the drawings of the models you made with their visual images. Make your own one or two more models from two or three matchboxes and complete their drawings.
Practical work No. 3
Modeling according to drawing
Rice. 58. Assignments for practical work No. 3
Directions for use. Modeling is the process of making a model of an object according to a drawing. You have already done this in labor lessons. Before you start modeling, you need to prepare the necessary material: cardboard, wire.
To make a cardboard model, first cut out its blank. Determine the dimensions of the workpiece from the image of the part (see Fig. 58). Mark (outline) the cutouts. Cut them along the outlined contour. Remove the cut out parts and bend the model according to the drawing. To prevent the cardboard from straightening after bending, draw lines on the outside of the bend with some sharp object.
The wire for modeling must be soft and of arbitrary length.
Date of introduction 01.01.71
This standard establishes the rules for depicting objects (products, structures and their components) in drawings of all industries and construction. The standard fully complies with ST SEV 363-88. (Changed edition, Amendment No. 2).
1. BASIC PROVISIONS AND DEFINITIONS
1.1. Images of objects should be made using the rectangular projection method. In this case, the object is assumed to be located between the observer and the corresponding projection plane (Fig. 1).1.2. The six faces of the cube are taken as the main projection planes; the edges are combined with the plane, as shown in Fig. 2. Face 6 may be placed next to face 4. 1.3 The image on the frontal plane of projections is taken as the main one in the drawing. The object is positioned relative to the frontal projection plane so that the image on it gives the most complete idea of the shape and size of the object. 1.4. The images in the drawing, depending on their content, are divided into types, sections, sections.
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1.5. View - an image of the visible part of the surface of an object facing the observer. To reduce the number of images, it is allowed to show the necessary invisible parts of the surface of an object in views using dashed lines (Fig. 3).
1.6 Section - an image of an object mentally dissected by one or more planes, while the mental dissection of an object relates only to this section and does not entail changes in other images of the same object. The section shows what is obtained in the secant plane and what is located behind it (Fig. 4). It is allowed to depict not everything that is located behind the cutting plane, if this is not required to understand the design of the object (Fig. 5).
1.7. Section - an image of a figure obtained by mentally dissecting an object with one or more planes (Fig. 6). The section shows only what is obtained directly in the cutting plane. It is allowed to use a cylindrical surface as a secant, which is then developed into a plane (Fig. 7).
(Changed edition, Amendment No. 2). 1.8. The number of images (types, sections, sections) should be the smallest, but providing a complete picture of the subject when using the symbols, signs and inscriptions established in the relevant standards.
2. TYPES
2.1. The following names of views obtained on the main projection planes are established (main views, drawing 2): 1 - front view (main view); 2 - top view; 3 - left view; 4 - right view; 5 - bottom view; 6 - rear view. In construction drawings, if necessary, the corresponding views may be given other names, for example, “facade”. The names of types on the drawings should not be inscribed, except as provided in clause 2.2. In construction drawings it is allowed to inscribe the name of the type and assign it an alphabetic, numerical or other designation. 2.2. If the views from above, left, right, below, from behind are not in direct projection connection with the main image (the view or section shown on the frontal plane of projections), then the direction of projection should be indicated by an arrow next to the corresponding image. The same capital letter should be placed above the arrow and above the resulting image (view) (Fig. 8).
Drawings are designed in the same way if the listed views are separated from the main image by other images or are not located on the same sheet with it. When there is no image that can show the direction of view, the name of the species is inscribed. In construction drawings, it is allowed to indicate the direction of view with two arrows (similar to indicating the position of cutting planes in sections). In construction drawings, regardless of the relative position of the views, it is allowed to inscribe the name and designation of the view without indicating the direction of view with an arrow, if the direction of view is determined by the name or designation of the view. 2.3. If any part of an object cannot be shown in the views listed in paragraph 2.1 without distorting the shape and size, then additional views are used, obtained on planes not parallel to the main planes of projections (Fig. 9-11). 2.4. The additional view must be marked on the drawing with a capital letter (Drawings 9, 10), and the image of an object associated with the additional view must have an arrow indicating the direction of view, with a corresponding letter designation (arrow B, Drawings 9, 10).
When an additional view is located in direct projection connection with the corresponding image, the arrow and view designation are not applied (Fig. 11).
2.2-2.4. (Changed edition, Amendment No. 2). 2.5. Additional types are arranged as shown in Fig. 9- 11. Location of additional views along the lines. 9 and 11 are preferable. An additional view can be rotated, but with, as a rule, maintaining the position adopted for a given item in the main image, and the designation of the view must be supplemented with a conventional graphic designation. If necessary, indicate the angle of rotation (Fig. 12). Several identical additional types related to one subject are designated by one letter and one type is drawn. If, in this case, parts of the object associated with an additional type are located at different angles, then a conventional graphic designation is not added to the type designation. (Changed edition, Amendment No. 1, 2). 2.6. The image of a separate, limited area of the surface of an object is called a local view (type D, figure 8; view E, figure 13). The local view can be limited to the cliff line, in the smallest possible size (type D, figure 13), or not limited (type D, figure 13). The detail view should be marked on the drawing like the supplementary view. 2.7. The ratio of the sizes of the arrows indicating the direction of view must correspond to those shown in Fig. 14. 2.6, 2.7. (Changed edition, Amendment No. 2).
3. CUT
3.1. The sections are divided, depending on the position of the cutting plane relative to the horizontal plane of projections, into: horizontal - the cutting plane is parallel to the horizontal plane of projections (for example, section A-A, Fig. 13; section B-B, crap. 15). In construction drawings, horizontal sections may be given other names, such as "plan"; vertical - the cutting plane is perpendicular to the horizontal plane of projections (for example, a section at the site of the main view, Fig. 13; sections A-A, B-B, G-G, Fig. 15); inclined - the secant plane makes an angle with the horizontal projection plane that is different from a straight line (for example, section B-B, Fig. 8). Depending on the number of cutting planes, the sections are divided into: simple - with one cutting plane (for example, Fig. 4, 5); complex - with several cutting planes (for example, section A-A, Fig. 8; section B-B, Fig. 15). 3.2. A vertical section is called frontal if the cutting plane is parallel to the frontal plane of projections (for example, section, Fig. 5; section A-A, Fig. 16), and profile if the cutting plane is parallel to the profile plane of projections (for example, section BB, Fig. 16 . 13).
3.3. Complex sections can be stepped if the cutting planes are parallel (for example, a stepped horizontal section B-B, Fig. 15; a stepped frontal section A-A, Fig. 16), and broken if the cutting planes intersect (for example, sections A-A, drawings 8 and 15). 3.4. The cuts are called longitudinal if the cutting planes are directed along the length or height of the object (Figure 17), and transverse if the cutting planes are directed perpendicular to the length or height of the object (for example, cuts A-A and B-B, Figure 18). 3.5. The position of the cutting plane is indicated in the drawing by a section line. An open line must be used for the section line. In case of a complex cut, strokes are also made at the intersection of the cutting planes. Arrows should be placed on the initial and final strokes indicating the direction of view (Fig. 8-10, 13, 15); arrows should be applied at a distance of 2-3 mm from the end of the stroke. The starting and ending strokes must not intersect the outline of the corresponding image. In cases like the one indicated in Fig. 18, arrows indicating the direction of view are drawn on the same line. 3.1-3.5. (Changed edition, Amendment No. 2). 3.6. At the beginning and end of the section line, and, if necessary, at the intersection of the cutting planes, the same capital letter of the Russian alphabet is placed. The letters are placed near the arrows indicating the direction of view, and at the intersection points from the outer corner. The cut must be marked with an inscription like “A-A” (always two letters separated by a dash). In construction drawings, near the section line, it is allowed to use numbers instead of letters, as well as write the name of the section (plan) with an alphanumeric or other designation assigned to it. 3.7. When the secant plane coincides with the plane of symmetry of the object as a whole, and the corresponding images are located on the same sheet in direct projection connection and are not separated by any other images, for horizontal, frontal and profile sections the position of the secant plane is not marked, and the cut is inscribed are not accompanied (for example, a section at the site of the main species, Fig. 13). 3.8. Frontal and profile sections, as a rule, are given a position corresponding to that accepted for a given item in the main image of the drawing (Fig. 12). 3.9. Horizontal, frontal and profile sections can be located in place of the corresponding main views (Fig. 13). 3.10. A vertical section, when the cutting plane is not parallel to the frontal or profile planes of projections, as well as an inclined section must be constructed and located in accordance with the direction indicated by the arrows on the section line. It is allowed to place such sections anywhere in the drawing (section B-B, Fig. 8), as well as with rotation to a position corresponding to that accepted for this item in the main image. In the latter case, a conventional graphic designation should be added to the inscription (section Г-Г, drawing 15). 3.11. For broken cuts, the secant planes are conventionally rotated until they are aligned into one plane, and the direction of rotation may not coincide with the direction of view (Fig. 19). If the combined planes turn out to be parallel to one of the main projection planes, then a broken section can be placed in the place of the corresponding type (sections A-A, drawings 8, 15). When rotating the secant plane, the elements of the object located on it are drawn as they are projected onto the corresponding plane with which the alignment is made (Fig. 20).
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3.12. An incision that serves to clarify the structure of an object only in a separate, limited place is called local. The local section is highlighted in the view by a solid wavy line (Figure 21) or a solid thin line with a break (Figure 22). These lines must not coincide with any other lines in the image.
3.13. Part of the view and part of the corresponding section can be connected by separating them with a solid wavy line or a solid thin line with a break (Fig. 23, 24, 25). If in this case half of the view and half of the section are connected, each of which is a symmetrical figure, then the dividing line is the axis of symmetry (Fig. 26). It is also possible to separate the section and view by a thin dash-dotted line (Fig. 27), coinciding with the trace of the plane of symmetry not of the entire object, but only of its part, if it represents a body of rotation.
3.10-3.13. (Changed edition, Rev. № 2). 3.14. It is allowed to combine a quarter of a view and quarters of three sections: a quarter of a view, a quarter of one section and half of another, etc., provided that each of these images is individually symmetrical.
4. SECTIONS
4.1. Sections that are not part of the section are divided into: external sections (Fig. 6, 28); superimposed (Fig. 29).
Extended sections are preferable and can be placed in a section between parts of the same type (Fig. 30).
(Changed edition, Amendment No. 2). 4.2. The contour of the extended section, as well as the section included in the section, is depicted with solid main lines, and the contour of the superimposed section is depicted with solid thin lines, and the contour of the image at the location of the superimposed section is not interrupted (Fig. 13, 28, 29). 4.3. The axis of symmetry of the extended or superimposed section (Fig. 6, 29) is indicated by a thin dash-dotted line without letters and arrows, and the section line is not drawn. In cases like the one indicated in Fig. 30, with a symmetrical sectional figure, the section line is not drawn. In all other cases, an open line is used for the section line, indicating the direction of view with arrows and denoted by the same capital letters of the Russian alphabet (in construction drawings - uppercase or lowercase letters of the Russian alphabet or numbers). The section is accompanied by an inscription like “AA” (Fig. 28). In construction drawings it is allowed to inscribe the name of the section. For asymmetrical sections located in a gap (Fig. 31) or superimposed (Fig. 32), the section line is drawn with arrows, but not marked with letters.
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In construction drawings, for symmetrical sections, an open line is used with its designation, but without arrows indicating the direction of view. 4.4. The section in construction and location must correspond to the direction indicated by the arrows (Fig. 28). It is allowed to place the section anywhere in the drawing field, as well as with a rotation with the addition of a conventional graphic designation 4.5. For several identical sections related to one object, the section line is designated by one letter and one section is drawn (Fig. 33, 34). If the cutting planes are directed at different angles (Fig. 35), then the conventional graphic designation is not applied. When the location of identical sections is precisely determined by the image or dimensions, it is allowed to draw one section line, and indicate the number of sections above the section image.
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4.6 Cutting planes are chosen so as to obtain normal cross sections (Fig. 36). 4.7. If the secant plane passes through the axis of the surface of rotation that bounds the hole or recess, then the contour of the hole or recess in the section is shown in full (Fig. 37). 4.8. If the section turns out to consist of separate independent parts, then cuts should be used (Fig. 38).
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4.4-4.8. (Changed edition, Amendment No. 2).
5. REMOTE ELEMENTS
5.1. A detachable element is an additional separate image (usually enlarged) of any part of an object that requires graphic and other explanations regarding shape, size and other data. The detail element may contain details not indicated on the corresponding image, and may differ from it in content (for example, the image may be a view, and the detail element may be a section). 5.2. When using an extension element, the corresponding place is marked on the view, section or section with a closed solid thin line - a circle, an oval, etc. with the designation of the extension element in a capital letter or a combination capital letter with an Arabic numeral on a leader line shelf. Above the image of the extension element, indicate the designation and scale in which it is made (Fig. 39).
In construction drawings, the extension element in the image can also be marked with a curly or square bracket or not marked graphically. The image from which the element is being taken out, and the extension element, may also have the alphabetic or numerical (Arabic numerals) designation and name assigned to the extension element. (Changed edition, Amendment No. 2). 5.3. The remote element is placed as close as possible to the corresponding place in the image of the object.
6. CONVENTIONS AND SIMPLIFICATIONS
6.1. If the view, section or section represents a symmetrical figure, it is allowed to draw half of the image (View B, Drawing 13) or slightly more than half of the image, drawing a break line in the latter case (Drawing 25). 6.2. If an object has several identical, evenly spaced elements, then the image of this object shows one or two such elements in full (for example, one or two holes, Fig. 15), and the remaining elements are shown in a simplified or conditional manner (Fig. 40). It is allowed to depict a part of an object (Fig. 41, 42) with appropriate instructions on the number of elements, their location, etc.
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6.3. In views and sections, it is allowed to depict in a simplified manner the projections of the lines of intersection of surfaces, if their precise construction is not required. For example, instead of pattern curves, circular arcs and straight lines are drawn (Fig. 43, 44).
6.4. A smooth transition from one surface to another is shown conditionally (Fig. 45-47) or not shown at all (Fig. 48-50).
Simplifications similar to those indicated in Fig. 51, 52.
6.5. Parts such as screws, rivets, keys, non-hollow shafts and spindles, connecting rods, handles, etc. are shown uncut in a longitudinal section. The balls are always shown uncut. As a rule, nuts and washers are shown uncut on assembly drawings. Elements such as spokes of flywheels, pulleys, gears, thin walls such as stiffeners, etc. are shown unshaded if the cutting plane is directed along the axis or long side of such an element. If in such elements of a part there is a local drilling, recess, etc., then a local cut is made, as shown in Fig. 21, 22, 53. (Changed edition, Amendment No. 2).
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6.6. Plates, as well as elements of parts (holes, chamfers, grooves, recesses, etc.) with a size (or difference in size) in the drawing of 2 mm or less are depicted with a deviation from the scale adopted for the entire image, in the direction of enlargement. 6.7. It is permissible to depict a slight taper or slope with magnification. In those images in which the slope or taper is not clearly visible, for example, the main view of the devil. 54a or top view of the devil. 54b, draw only one line corresponding to the smaller size of the element with a slope or the smaller base of the cone. 6.8. If it is necessary to highlight the flat surfaces of an object in the drawing, diagonals are drawn on them with solid thin lines (Drawing 55). 6.9. Objects or elements that have a constant or naturally changing cross-section (shafts, chains, rods, shaped steel, connecting rods, etc.) may be depicted with breaks. Partial images and images with breaks are limited in one of the following ways: a) a continuous thin line with a break, which can extend beyond the contour of the image by a length of 2 to 4 mm. This line may be inclined relative to the contour line (Fig. 56a);
B) a solid wavy line connecting the corresponding contour lines (Fig. 56b);
C) hatching lines (Fig. 5bv).
(Changed edition, Rev. № 2). 6.10. In drawings of objects with a continuous mesh, braiding, ornament, relief, knurling, etc., it is allowed to depict these elements partially, with possible simplification (Drawing 57).
6.11. To simplify drawings or reduce the number of images, it is allowed: a) the part of the object located between the observer and the cutting plane is depicted with a dash-dot thick line directly on the section (superimposed projection, Fig. 58); b) use complex cuts (Fig. 59);
C) to show holes in the hubs of gear wheels, pulleys, etc., as well as for keyways, instead of a full image of the part, give only the outline of the hole (Fig. 60) or groove (Fig. 52); d) depict in section the holes located on the round flange when they do not fall into the secant plane (Fig. 15). 6.12. If a top view is not necessary and the drawing is compiled from images on the frontal and profile planes of projections, then with a stepped section, the section line and inscriptions related to the section are applied as shown in the drawing. 61.
6.11, 6.12. (Changed edition, Amendment No. 2). 6.13. Conventions and simplifications allowed in permanent connections, in drawings of electrical and radio engineering devices, gears, etc., are established by the relevant standards. 6.14. The conventional graphic designation “rotated” must correspond to the line. 62 and “expanded” - damn. 63.
(Introduced additionally, Amendment No. 2). APPENDIX according to GOST 2.317-69.
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Committee of Standards, Measures and Measuring Instruments under the Council of Ministers of the USSR DEVELOPERS V.R. Verchenko, Yu.I. Stepanov, Ya.G. Old-timer, B.Ya. Kabakov, V.K. Anopov 2. APPROVED AND ENTERED INTO EFFECT by the Decree of the Committee of Standards, Measures and Measuring Instruments under the Council of Ministers of the USSR in December 1967. 3. The standard fully complies with ST SEV 363-88 4. INSTEAD GOST 3453-59 in terms of section. I - V, VII and appendices 5. EDITION (April 2000) with Amendments No. 1, 2, approved in September 1987, August 1989 (IUS 12-87, 12-89)
| 1. Basic provisions and definitions. 1 2. Types.. 3 3. Sections.. 6 4. Sections. 9 5. Detailed elements.. 11 6. Conventions and simplifications. 12 |
>>Drawing: Types. Number of views in drawings
You already know that projection drawing images are called projections. Images used on technical drawings, are called species.
View- This is an image of the visible part of the surface of an object facing the observer. The standard establishes six main views, which are obtained by projecting an object placed inside a cube onto all its faces (Fig. 130). The six faces of the hollow cube are rotated until they align with the frontal plane of projections (Fig. 131).
The following species names have been established:
1.Front view - main view (located at the site of the frontal projection).
2.The top view (under the main view) is placed in place of the horizontal projection.
3.Left view (located to the right of the main view).
4.Right view (located to the left of the main view).
5.Bottom view (located above the main view).
6. Rear view (located to the right of the left view).
The names of the species are not indicated on the drawings. The main view is the image obtained on the back face of the cube, which corresponds to the front projection plane.
The object is positioned relative to the frontal plane of projections so that the image on it gives the most complete idea of the shape and size of the object.
The number of views in the drawing should be minimal, but sufficient to understand the shape of the depicted object. In views it is allowed to show the necessary invisible parts of the surface of an object using dashed lines (Fig. 132).
In the drawing, the distance between views is chosen arbitrarily, but in such a way that dimensions can be drawn. It is not allowed to put the same dimension twice on the drawings, as this clutters the drawing and makes it difficult to read and use in work. Views, like projections, are arranged in a projection relationship.
When constructing drawings, sometimes only part of the view is completed. The image of a narrowly limited area of the surface of a part is called a local view. Native species are limited to the cliff line (Fig. 133). In Fig. 133 local view is located in projection connection. In this case it is not indicated. In the front view, an arrow indicates the direction of view.
If a local view is not located in a projection connection, then in the view it is indicated by an arrow and a letter of the Russian alphabet, and the image of the local view itself is inscribed with the same letter (Fig. 134).
It is allowed to put down dimensions on local views.
Questions and tasks
1. Define the concept of “species”.
2. How are the views arranged in the drawings?
3. Name the images presented in Fig. 135, 136.
4. What does the dashed line mean in the view on the left (Fig. 136)?
5. Why is a drawing the main graphic document in production?
6. Using the visual representation of the part (Fig. 137), find the corresponding main view and top view. Write the answer in your workbook.
7. In Fig. 138 arrows A, B, C show the projection directions. Select the projection direction that should correspond to the main view of the part.
8. Determine how many images are needed to identify the shape of the parts (Fig. 139). Explain what signs you propose to use to reduce the number of species. Give your answer in writing.
N.A. Gordeenko, V.V. Stepakova - Drawing., 9th grade
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