Making three types of drawings based on this visual representation of the part. Carrying out a drawing of three types based on a given visual image of the part Drawing construction of 3 types
5.1. View placement rules. To fully identify the shape of objects in drawing, they use various images: types, 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 main view gave the most complete idea of the shape and size of the object.
Image on horizontal plane projections are 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.
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. Cutout in detail rectangular shape turned out to be invisible in the top view, so it is shown as 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. Have local species on the 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
Copy the data in Figure 56 and the drawings into your workbook and supplement them with an 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 out of two or three matchboxes and complete their drawings.
Practical work No. 3
Modeling according to drawing
Rice. 58. Tasks for practical work № 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 required 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.
Drawing a side view of an object seems the simplest and most intuitive - without “perspective” it’s easy and fun to draw. However, due to their simplicity, side view drawings are also quite boring, and they are very problematic in conveying the character and qualities of the subject. In this short tutorial I'll show you how to turn them into an interesting, 3D drawing using simple trick in Photoshop.
1. Prepare a side view drawing
Step 1
Open Adobe Photoshop. Create a new document (Ctrl/Cmd-N) and draw a side view of your character on a new layer (Ctrl/Cmd-Shift-Alt-N).
Step 2
Install Opacity(Opacity) of the layer by 20%. Then create a new layer.
Step 3
On this new layer, draw a simplified version of the character. Keep the shapes as simple as possible, forget about the details for a second.
2. Build a binding box
Step 1
Every three-dimensional object, regardless of the level of detail, can be enclosed in a so-called box. Likewise, the side view (2D) can be enclosed within one side of this box - a rectangle. Let's build it!
Select Rectangle Tool(Rectangle Tool (U)) and change its settings as shown below.
Step 2
Draw any rectangle. Don't bother creating a new layer - for shapes they are created automatically.
Step 3
Use the tool Free Transform Tool(Free Transform (Ctrl/Cmd-T)) to resize the rectangle and fit the character tightly inside. Hide the character (click on the "eye" icon next to the corresponding layer in the layers panel).
Step 4
Duplicate ( Ctrl/ cmd- J) rectangle and hide the original.
Now we need some rules of perspective. You can find them in my other lessons on perspective - they are not as difficult as you might think. Here's an example!
- If you want to see the front of the character, make the rectangle narrower to the left.
- If you want to see the back of the character, make the rectangle narrower to the right.
- If you want to see the top of the character, make the rectangle shorter at the top.
- If you want to see the bottom of the character, make the rectangle shorter at the bottom.
Step 5
The side view must be distorted to transform into a 3D view. Restore the visibility of the layer with the original rectangle and lower it Opacity(Opacity). Use Direct Selection Tool(Node Selection Tool (A)), hold Shift and click on the dots on the side near the “space”.
When both points are selected, click the down arrow to move them down. We now have one side of the binding box!
Step 6
The side view contains information about the height and length of the character, but 3D is three measurements.
Create a new layer. Remove the visibility of the rectangle, but return the visibility of the character layer. Turn on the rulers (Ctrl/Cmd-R) and drag them horizontally towards the picture to measure out the most important parts of the character. Use these lines to draw a simple top view.
Hint: you can draw only half of the top view and then duplicate it (Ctrl/Cmd-J) and Edit > Transform > Flip Vertical(Edit > Transform > Flip Vertical).
Step 7
Create a connecting rectangle for the top view as before.
Step 8
Return to the distorted rectangle. We can create the second part of our “box” from it. Drag it while holding Alt to duplicate it. Move it according to the rules of perspective:
If you want to see the front, move to the right.
If you want to see the back, move to the left.
If you want to see the top, move down.
If you want to see the bottom, move it to the top.
Regarding distance:
The narrower the length, the greater the horizontal distance.
The lower the height, the greater the vertical distance.
The distance cannot be greater than the width in the top view.
Step 9
Connect the sides using Pen Tool(Pen (P)) (using the same settings as the rectangle). Our box is ready!
3.Adjust side view for 3D link box
Step 1
Now we need to fit the character inside the box. First, use Free Transform Tool(Free Transform (Ctrl/Cmd-T)) while holding down the Shift key to adjust the height of the character to the height of the box.
Step 2
Hold Ctrl/Cmd and drag the bottom point to the bottom corner of the far side. Do the same with the top point. Our goal is to "attach" the character to the distorted side.
Step 3
Hold Alt and drag the character to place a copy on the other side.
Step 4
The problem is that not every body element is the same width. Let's look at the example of a muzzle. Create a new layer to draw a line between the bases of the face on both sides.
Now draw the same line between both sides in the top view.
Step 5
As you can see, the muzzle starts a little deeper rather than right near the sides.
Try to imitate similar proportions on this line:
Step 6
Select a face on one side using Lasso Tool(Lasso (L)). Cut and paste it into place on a new layer.
It is known that frontal, horizontal and profile projections are images of a projection drawing. Species It is customary to name those images on mechanical engineering drawings that represent projections of the external visible surfaces of objects. It can also be said that under species refers to the visible parts of the surfaces of objects facing the observer and shown in the drawings.
Arrangement of views in the drawing
According to the current standard, three types are distinguished: basic, local and additional.
Guided by GOST 2.305 – 68, kinds, which are obtained on all main projections of planes, have the following names:
Main view(front view). It is located in the place where it is located frontal projection
View from above. Located under the main view, that is, in the place where the horizontal projection is located
Left view. Placed to the right of the main view, in the place where the profile projection is located
Right view. Located on the left side of the main view
Bottom view. Placed above the main view
Back view. Located from right side from left view
Just like all projections, the main views are in a projection relationship. When drawing up mechanical engineering drawings, developers try to select as few views as possible, and at the same time, so that the shape of the depicted object is represented accurately and in all details. In cases where this is necessary, those parts of the surfaces of objects that are invisible can be designated using dashed lines.
The most complete information about the object depicted in the drawing should be provided by the main view. For this reason, the location of the part relative to the frontal plane of projections must be carried out in such a way that it is possible to project its visible surfaces indicating the largest number of elements that determine the shape. In addition, it is the main view that should demonstrate all the features of the part’s shape, ledges, surface bends, silhouette, holes, and notches. This must be done in order to ensure the fastest possible recognition of the shape that the depicted product has.
On drawing graphic documents, names of types are not applied, except in cases where they are in direct and immediate projection connection with the main image of the part.
Views outside the projection link
In order to use the working field of the drawing in the most rational way, in accordance with current norms and standards, it is allowed to depict views in any place, and without any projection connection.
Those views that are located without a projection connection with the main view should be designated by different letters of the Cyrillic alphabet (Russian alphabet), and as for the direction, arrows should be used to indicate it.
Arrow sizes
All arrows that are placed on the drawings in the case of displaying a view outside the projection connection must have strictly defined dimensions, which are established by current standards.
Arrangement of views on the drawing field
The main requirement that the placement of the main and other main views on the drawings must meet is rationality. In this case, it is also necessary to take into account the placement of text material and the need to apply dimensions. According to current standards, it is not permissible to arrange views in drawings in such a way that it interferes with the full representation of the shape of the part in the main view.
Rational arrangement of species
By rational arrangement of views in mechanical engineering drawings we mean such an arrangement that provides a complete picture of the shape and all the features of the depicted part.
Applying breaks
In cases where the objects depicted in the drawings have areas where cross section or is constant, or changes in a regular way, it is permissible to depict them with breaks. In this case, the contours of these breaks should be indicated using a solid thin wavy line.
Local view
Local view refers to an image of a separate section of the surface of an object, which is formed by projecting it onto one of the main projection planes.
It is permissible to limit the local view using a thin wavy cliff line. In cases where a local view is depicted outside the projection connection, the direction of view on the main view is indicated with an arrow, and a letter designation is applied to this local view.
Additional views
Date of introduction 01.01.71
This standard establishes the rules for depicting objects (products, structures and their constituent elements) on 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 additional types damn 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, the parts of the object associated with the additional type are located at different angles, then the designation of the type is conditional graphic designation do not add. (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 may be limited to the cliff line, if possible in smallest size(type D, drawing 13), or not limited (type D, drawing 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; cuts A-A, V-V, G-G, damn. 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, drawings 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, features 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 side external 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 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 a callout 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 callout element in a capital letter or a combination of a capital letter and an Arabic numeral on the shelf of the leader line. 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. On the image from which the element is being taken out, and on the extension element, it is also allowed to apply the alphabetic or numeric number assigned to the extension element ( Arabic numerals) designation and name. (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 such elements of the part have local drilling, recess, etc., then do local incision, 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. Anopova 2. APPROVED AND ENTERED INTO EFFECT by the Resolution of the Committee of Standards, Measures and measuring instruments at 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 |
A drawing is one of the main documents from the package of working documentation for a product. The designer must make a graphic representation of the part or product so that in any production facility, hundreds or thousands of kilometers away, they can be manufactured without seeking advice. In order for information about the product to be perceived and interpreted unambiguously, certain uniform rules have been introduced for the design of drawing images and the arrangement of individual elements on them.
Application area
Methods for displaying objects are universal and cover drawings and other design materials various fields, both construction and industrial. This includes industry household appliances, electronics, transport and communications. They regulate how objects are displayed using two-dimensional drawings and three-dimensional models. The methods, types, and arrangement of product types in the drawing are regulated.
Regulatory acts
The regulatory act in this area is GOST 2.305-2008.
Download GOST 2.305-2008 “Images - views, sections, sections.”
The document details acceptable methods for naming views in drawings, as well as additional ways presentation of information about the part: cuts and sections. It also regulates the location of extension elements and permitted methods for simplifying drawings.
Kinds
The preferred method for depicting three-dimensional products on a plane is orthogonal projection. The location of the depicted object is assumed to be between the conventional observer and the projection plane. To improve the readability of the image, a simplified approach is permitted. Therefore, the images in the drawings are not projection in the strict geometric sense of the word. They are called images on a plane. To obtain the main projections, the depicted part is placed in the center of an imaginary cube. Its faces will serve as projection planes.
As a result of the projection of the image of the object, a diagram of the main types of the product appears:
- front;
- on right;
- below;
- left;
- above;
- behind.
In technical drawing, the front view is considered the main one. It should give maximum information about the depicted detail. It is complemented by views from the left and from above (relative to the main one). These three types are called the main ones. The rest are considered auxiliary. Their images are built if important design information about the product complex shape not visible in the three main views.
In addition, to explain the structure of part of the part, local views are used, showing a fragment of the image of the main view. Such images are placed in unoccupied areas, inscribed in capital letters of the Cyrillic alphabet. On the main view, in the area where the fragment is located, there is an arrow showing the direction of the conditional view, as a result of which the local view appears. Such drawings are limited by break lines drawn in the direction minimum size element.
In addition, additional types are used. They are built on planes placed at an angle to the main faces of the projection cube. They help to illustrate the location and structure of those parts of the object that are not visible or are not sufficiently presented in the main views, or their dimensions and configuration are distorted. The designation of additional species is carried out using letters of the Cyrillic alphabet.
A thoughtful selection of local and additional views allows you to reduce the number of shadings when displaying internal structure details not visible on the main projections. The readability of the drawing, the relative position of its parts also improves, and the likelihood of its erroneous interpretation is reduced.
Cuts
For demonstration internal structure object, it is dissected with one or a large number secants. The image of a part with a volume cut off by such a plane is called a section. It shows the part of the object that is in and behind the cutting planes.
Classification
Incisions are divided into several types:
- Simple. One cutting plane is used.
- Complex. There are two or three planes. In particularly difficult cases, a larger number is used.
Simple cuts are divided according to the orientation of the secant into:
- horizontal;
- vertical;
- inclined.
According to their configuration, complex ones are divided into stepped and broken.
Based on the parallelism of the secant to any main plane, vertical planes are divided into frontal and profile. Based on the same feature, stepped ones are distinguished between horizontal and frontal.
For axisymmetric objects, sections are also distinguished based on the direction of the secant to this axis:
- longitudinal;
- transverse.
The location of the secant is displayed with a thick (one and a half times thicker than the main) dashed line with a length of dashed lines of 8-20 millimeters. The direction of projection is shown by arrows orthogonal to the strokes. The cutting plane is called double letters: “A-A”
Performance
Images of sections parallel to the plane of the main view are placed near it.
Local cuts are separated by wavy lines. When depicting them, you should avoid placing them in the area of other elements, coinciding with them or intersecting them.
The location of the complex stepped section is recommended adjacent to the supporting main view. You can also place them in free areas of the image.
When displaying broken sections of a section in drawings, they are rotated so that they are combined into a single hypothetical plane. The location of parts of the object located behind the rotated plane is hidden.
Sections
If, during a conditional dissection of an object, we leave only that part of it that is in the secant plane, we get section in his drawing sense.
Sections are divided into:
- being part of the cut;
- independent.
Among the independent ones there are:
- Taken out. They are drawn behind the outline of the main view. They are recommended by the standard as preferred.
- Overlaid. Placed directly on the drawing of the corresponding type or in its gap. Sometimes the design document becomes difficult to read.
The system of location, designation and naming of sections is similar to the system of designation of sections. It is important to remember that lines indicating sections cannot intersect with drawing elements. The secant trace is displayed as a thick line with a break.
Detail elements
If part of a detail drawing needs to be displayed in more detail than the selected scale of the main drawing allows, so-called callout elements are used.
The location of the extension element in the main view is indicated by a closed contour, most often round or oval. From there there is a thin arrow leading to the placement of a detailed image. If such a line is not drawn, the letter designation of the element is written above the extension line, and the letter is repeated above the detailed drawing.
Sometimes the callout element may differ from the type of the main image. Display in the form of sections, cuts, etc. is allowed.
Detailed linear and angular dimensions, information on accuracy, quality and roughness, as well as other necessary information.
Conventions and simplifications
To make drawings easier to read and understand, it is allowed to depict a part on them that is not 100% in accordance with the actual shape, using the following conventions and simplifications:
- For parts that have a central axis of symmetry, it is allowed to draw half the contour. As a rule, an incision or section is placed in the location of the second half.
- If the design includes several identical elements, one of them is displayed in detail, with dimensions and tolerances; the location of the others is simplified in the form of contours or their number is simply indicated.
- The transition between surfaces can be reflected conditionally or omitted altogether.
- Fastening parts, spherical elements, shafts, handles, etc. on longitudinal sections they are drawn without dissection.
- For thin-walled parts, an image on an enlarged relative to the general scale is allowed.
- For greater clarity, it is permissible to increase the angle of the cone or slope.
- The flat edges of the part are highlighted with diagonal thin lines.
- Parts of long length with an unchanged profile are depicted with a gap, marking its places with broken or wavy lines.
- The knurling or notch may be partially depicted.
In some specific cases, additional simplifications are applied. Acceptable conventions in arrangement individual species drawings, such as gears, electronic components and devices, etc., are described in the relevant standards.
When simplifying a drawing, the designer should take precautions so that the document that comes out from under his mouse does not turn into a puzzle that will take his partners a lot of time to solve.
