Drawing practical work 18. Rules for reading assembly drawings, conventions and simplifications

MBOU "Tagninskaya OOSh"

Zalarinsky district

Irkutsk region

Drawing and technology teacher

Tretyakova Elena Nikolaevna

Drawing lesson Grade 9

Lesson topic:Practical work No. 18 "Reading assembly drawings"

Lesson type: Generalization and consolidation of knowledge on the topic: "Assembly drawings"

Goals and objectives of the lesson:

Lesson equipment: multimedia complex, presentation created in the MS Power Point program, textbook by A. D. Botvinnikov, V.N. Vinogradov, I.S. Vyshnepolsky *AST * Astrel * Moscow * 2009 Tables 16, 17, 18, 19, geometric shapes, cards - tasks, a sample of the work performed.

Basic knowledge of students:- drawing, - assembly drawing, - assembly unit, - types of sections, - rules for applying dimensions, - rules for applying cuts, - rules for drawing leader shelves, - rules for applying position numbers.

Lesson control: students' performance at the blackboard, reading drawings from posters, explanations on the screen, independent work on cards.

Interdisciplinary connections:

Geometry.

technology

Working methods and techniques: students' stories, comparison and reading of drawings, conversation, discussion, work with tables and posters, work with a textbook, individual (differentiated work on cards).

During the classes.

1. Organizational moment.

In the lesson, we will need felt-tip pens or colored pencils, a drawing tool.

Prepare your workplace, leave only the essentials.

2. Motivation of educational activity. (slide 1)

In the age of development of science and technology, any self-respecting person should be able to disassemble and assemble a simple product, be able to describe it in a conversation with an interlocutor, sketch a sketch of this product on a piece of paper.

(slide 2)

And in order to cope with the practical work and read the assembly drawing, we need to know the basic rules for reading the assembly drawing and answer some questions.

3. Formation of knowledge, skills and abilities.

Repetition and consolidation

What shape are these geometric shapes? (slide 3)

The teacher shows the geometric bodies on the slide, and the students must select them from the presented models, name and show them.

(slide 4)

- students' answers (All dimensions are not shown on the assembly drawings. They show overall, connecting, axial)

slide 5)

- answers of students (Frontal, horizontal, profile. Full, connection of part of the view and section, connection of half of the view and section)

4) How the hatching of different parts is shown in the section of the assembly drawing

(screw, key, bolt, washer, nut, shaft)? (slide 6)

- students' answers (These details in the section are not hatched if the cutting plane passed along the axis of symmetry)

(slide 7)

- answers of students (Specification. The full name of the drawing being executed is entered, who checked it, the date the drawing was completed, the name of the product, the names of the parts in the product by position numbers, the material from which the parts are made, the dimensions of standard parts, for example, screws, bolts, nuts, image scale)

(Slide 8)

- answers of students (Shelves of callouts. Strictly vertically in order and strictly horizontally)

7) Read the assembly drawing orally ( slide 9), tables 16-19

According to the tables, students read assembly drawings according to the plan proposed in the textbook on pages 185-186 paragraph 35.

4. Practical work No. 18

Now I will remind you how to complete the task that you will be given for practical work (showing a card) and (slides 10-12)

Cards are different in complexity - the easiest, if successfully completed, are rated at "4" and the most difficult will be rated at "5"

There are 4 tasks in the card

Plan - diagram on the board (slide 13)

Draw dimension lines.

Correctly show the cut (apply shading).

Correctly show the number of parts in the drawing using shelves - callouts and correctly place the position numbers.

Repeat task (to understand the work being done)

And here are the cards with the completed task.

5) Practical work of students.

6) Checking and collecting cards, self-test.

THANK YOU FOR YOUR WORK! (Slide 14)

Literature: Textbook A.D. Botvinnikov, V.N. Vinogradov, I.S. Vyshnepolsky *AST * Astrel * Moscow * 2009

View presentation content
"Reading assembly drawings"

MBOU "Tagninskaya OOSh"

Zalarinsky district

Irkutsk region

Drawing and technology teacher

Tretyakova Elena Nikolaevna

Drawing lesson in grade 9 Topic: Practical work No. 18 "Reading assembly drawings"

Goals and objectives of the lesson:
To form knowledge about the purpose, design of assembly drawings.
Learn to compare and read working and assembly drawings, read specifications.
Develop spatial thinking and memory as a condition for preparing for work and creative activity.
To cultivate the desire to conscientiously and rationally perform educational tasks, to develop cognitive interest and logical thinking.
To acquaint with the most important rules, symbols used in technical drawing, and their significance in modern science and production.
To promote the development of students' culture of work, skills in the proper organization of the workplace, rational methods of working with a drawing tool, accuracy and accuracy in work.

Color each piece with your own color.
Draw dimension lines
Correctly show the cut (apply hatching)
Correctly show the number of parts in the drawing using shelves - callouts and correctly place the position numbers

Literature

Textbook A.D. Botvinnikov, V.N. Vinogradov, I.S. Vyshnepolsky *AST * Astrel * Moscow * 2009

In the 9th grade program, images of parts connections immediately precede the transition to the study of assembly drawings.
This is due to the thematic proximity of these sections. The drawing of the connection of parts can be considered as a simplified version of the assembly drawing.
However, in general, both types of images are not identical in their content. Drawings of detachable and one-piece connections of parts can be regarded as fragments of assembly drawings.

Competence. KNOWLEDGE. Knowledge of typical connections: bolted, screw, stud, key, pin, welding, riveting, etc. SKILL. The ability to distinguish them and recognize them in the drawings, as examples of the simplest assembly drawings.

Use the reproductive method, in the form of a game. (Traffic light)
Demonstration of knowledge by students obtained in previous lessons.
(The teacher selectively shows drawings of typical connections of parts while making mistakes, and students need to confirm with a color token: red - not true,
green is correct.

Learning new material

We pose a problem to the students. (What questions would you ask on the topic “Reading an assembly drawing?”
Questions from students.
What do we mean by reading an assembly drawing?
What is the sequence of reading an assembly drawing?
What are the difficulties in reading assembly drawings?
An analysis of such questions shows that they can generally be divided into three main groups.
Questions of a geometric and projection nature;
Issues related to special conventions and simplifications used in assembly drawings;
Issues of a constructive nature related to the device of the assembly unit, the design of its parts, purpose, action, disassembly and assembly procedure.

Introduce the concept of an assembly drawing; conventions and simplifications on assembly drawings; give the concept of “specification”, “item numbers”.

Knowledge
The concept and definition of "assembly drawing", "detail", "product", "specification".
Practical application of assembly drawings, their use in professional activities.
Location of views on assembly drawings, additional and local views; cuts and sections, position numbers, leader lines, shelves, dimensioning.
Algorithm for reading an assembly drawing.

Assembly drawing, assembly drawing assignment

Reading an assembly drawing means presenting the shape and design of the product, understanding its purpose, operating principle, assembly procedure, and also identifying the shape of each part in a given assembly unit. (The method is reproductive, partially exploratory. The form is frontal, individual)

Algorithm for reading an assembly drawing
1. Study the content of the main inscription, finding out the name of the assembly unit and the scale of its image.
2. Consider the views, sections, sections on the assembly drawing and present the shape and dimensions of the product depicted on it.
3. Using the specification, determine how many parts the product consists of, find out the name of each of them and the material from which they are made.
4. Determine the shape of each part by considering their images on the assembly drawing.
5. Identify the types of connections of parts used in the product. Select standardized parts for which drawings are not performed.
6. Establish the principle of operation and the sequence of assembly of the product.

Dimensions applied on assembly drawings

These include:
1. Overall dimensions, i.e. the largest external dimensions of the product in three dimensions (height, length, width).
2. Installation dimensions, i.e. the dimensions that are necessary to install the assembly unit at the place of use.
These are the dimensions that determine the correct installation of the product during installation: the distance between the centers of the holes for installing bolts, screws, studs, etc.
3. Connecting dimensions, i.e. dimensions of the elements of a part, product, providing the possibility of attaching them to another product
4. Mounting dimensions, i.e. dimensions necessary for the correct installation of parts relative to each other, for example, dimensions between center and center lines.
5. Reference dimensions are affixed only if necessary. Sometimes on assembly drawings all dimensions may be reference. Most often, on assembly drawings, overall dimensions are reference.

Assembly drawing specification

Each assembly drawing is accompanied by a specification.
A specification is a text design document that defines the composition of an assembly unit, complex or kit.
Description of the specification is given in GOST 2.108-68, GOST 2.105-79 and GOST 2.113-73. It is carried out on an A4 sheet, which is drawn up with an internal frame and contains the main inscription of the drawing. Specification columns are placed above the main inscription.
It is allowed to combine the assembly unit specification with the drawing if it is made on an A4 sheet.
On training drawings of assembly units, it is allowed to reduce the size of the main inscription and fill out the specification in an abbreviated form.

Conventions and simplifications on assembly drawings

Formation of skills and abilities of reading an assembly drawing.

REINFORCING THE KNOWLEDGE GAINED IN THE LESSON
Methods
According to the source of knowledge: practical, visual.
According to the nature of cognitive activity: partially search.
Reading a blueprint (problem):
Imagine that in the store you bought a product that you need to assemble yourself. What are your first steps?
Forms
Pair work.
Individual.

Consolidation of knowledge gained in the lesson

PRACTICE #18 Reading assembly drawings

1. Figures 244-248 show assembly drawings of five different products, and Figure 249 shows visual images of six products. Some of them are given in figures 244-248, but not all. Determine which visual images, indicated by letters, represent exactly those products that are also contained in the assembly drawings. Write down in your workbook which of the visual images shows which product. Recording form: “On a visual image A is drawn ...” (take the name of the product from the assembly drawing).

Do not forget that not all assembly drawings are given illustrative images.
This kind of tasks develop attention and logical thinking.

Reading a drawing of a simple assembly unit The task contains the method of "brainstorming" on logical thinking. Teaches to analyze the shape of the product and its purpose.

There is an error in the faucet drawing.
present the shape and design of the product;
understand its purpose, the principle of operation;

The whirlpool of problems and solutions method

To implement this method, it is necessary to divide a group of students into subgroups of 2-3 people.
Each group is given a task and colored markers (so that each group has its own individual color)
Each group receives an assembly drawing by lot, which must be read and the answers recorded in writing. (5 minutes.)
Clockwise, the groups exchange assembly drawings and mark against each item:
"+" - agree with this answer;
"-" - do not agree with this answer;
"?" - this answer requires clarification of the authors.

In this way, the group's answer sheet goes through all the groups in the class, and each group leaves comments. Due to the fact that each team has a different color of markers, this makes it easier to identify the markings. After making a full circle, the sheet returns to the group. The team is invited to familiarize themselves with the proposals and additions of other groups. The students present their position and answer clarifying questions from the participants. Each team is given 5 minutes to present and answer.

This task can be done individually or in small groups.

The extreme or intermediate position of the part. In Figure 232, the image of the pusher is continued upwards with a dash-dotted thin line with two dots. What does this mean?

The pusher moves up and returns to its original position. On assembly drawings, the extreme or intermediate position of the part is shown with a dash-dotted thin line with two dots.

Please note that in view A (see Fig. 232) the handle (det. 2) is not shown. The shape of this part is determined by other images. In this view, it would cover the part of the handle that has a threaded hole. In such cases, the detail is not shown, and the inscription is made on the drawing: "The handle (det. 2) is not shown."

Image of border details. Sometimes on the assembly drawing it is necessary to show parts that are not included in this product. Part of such a part is shown in Figure 248. It is outlined with a thin line. This makes it possible to distinguish it from the parts included directly in the product.

Picture of sealing devices. To prevent leakage of liquid, steam or air between the moving parts of various taps, valves and pipelines, sealing devices are used.

One of them is an stuffing box (Fig. 242). For the sealing packing, it uses salted hemp, squeezed with a pressure sleeve. The sleeve (it is indicated by the arrow with the number 1) is connected to the body of the part by a thread. By tightening the sleeve, you can compress the packing so that it fits snugly against the cylindrical axis. In the drawing, the packing (it is indicated by an arrow with the number 2) is shaded in a cage as a non-metallic material (see Fig. 198).

Rice. 242. Stuffing box

When drawing stuffing boxes, the pressure sleeve is always depicted in the extended (initial) position.

Reducing the number and size of images. In assembly drawings, as well as in detail drawings, to reduce the number of images, you can connect half the view with half the section (Fig. 242 and 243). You can also connect a view part to a section part.

Rice. 243. Conditional image of repeating elements

To reduce the size of the image without reducing the scale, apply a break (see Fig. 242, top view).

Image of the same elements. Instead of several identical elements, it is allowed to depict only one of them on assembly drawings. So, for example, in Figure 243 only one bolt with a nut is shown (det. 3 and 4). The position of the rest is shown by the intersection of the center lines. And figure 242 shows only one of the four identical bolt holes.

Which line shows the extreme or intermediate position of the part on the assembly drawings? When is this image used?
How to understand the inscription on the assembly drawing: "The handle (det. 2) is not shown"?
When on the assembly drawing is the part outlined not by the main one, but by a thin line? What does it mean?
How to reduce the number of images on the assembly drawing, if you need to show both the external view and the internal structure of the product?

Practical work No. 18. Reading assembly drawings

Figures 244-248 show assembly drawings of five different products, and Figure 249 shows illustrative images of six products. Some of them are given in figures 244-248, but not all. Determine which visual images, indicated by letters, represent exactly those products that are also contained in the assembly drawings. Write down in your workbook which of the visual images shows which product. Recording form: “On a visual image A is drawn ...” (take the name of the product from the assembly drawing).
Do not forget that not all assembly drawings are given illustrative images.
Read the assembly drawings indicated by the teacher in figures 244-248, following the sequence given in 35. Answer questions (including additional ones) in writing.

Additional questions for assembly drawings

Rice. 244. Drawing for reading

Back to Figure 244

Why item 37 is not shaded
Why is detail 2 cross-hatched?

Rice. 245. Drawing for reading

Back to Figure 245

Image B-B is a section or section?
Why is it given?

Rice. 246. Drawing for reading

Back to Figure 246

Why was incision A - A made?
What is the shape of item 5?

Rice. 247. Drawing for reading

Back to Figure 247

Why is detail 3 cross-hatched?
Why does the hatching of parts 1 and 2 have a different direction?

Rice. 248. Drawing for reading

Back to Figure 248

Which line represents the workpiece?
Why is a special screw (det. 3) not shaded in section A-A, but shaded in section B-B?

Complete technical drawings of one or two parts suggested by the teacher. An appropriate visual image will help you complete the work.

Rice. 249 Exercise task

Purpose and arrangement of assembly units included in practical work No. 19.

The handle (Fig. 244) is attached to the door leaf with screws, for which holes are provided on the base (det. 1). The handle consists of a base and a handle connected with a screw (det. 3).
Puller (Fig. 245) - a device for removing pulleys, bearings and other parts from the shafts.
The main parts of the puller: the rocker (det. 1), on which the grippers (det. 3) are put on, and the pressure screw (det. 2). The limiter (det. 4) fixed with screws (det. 5) prevents the gripper from slipping off the rocker arm.
The dismantled device is installed on the protrusions of the grips. The shooting of parts is carried out by rotating the pressure screw, into the hole of which a rod (lever) is inserted for this purpose.

Device (Fig. 246) - the jig is used when drilling holes on tiles, in this case having a rectangular ledge.
The base (det. 1) of the conductor is connected to the plate (det. 2) with pins (det. 5) and screws (det. 6). On top of the plate there is a guide sleeve (det. 3), a handle (det. 4) is screwed in from the side.
When drilling a hole, the protrusion of the workpiece is inserted into the rectangular hole of the base, the drill is guided through the sleeve from above.
The roller (Fig. 247) serves as a support for moving heavy objects. It is used in sets of several pieces. The roller (det. 2) with a rubber tire (det. 3) is attached to the base (det. /) with a bolt (det. 4) and a nut (det. 5) with a washer (det. c).
The consignment note jig (Fig. 248) is used when drilling, in this case, two holes with a diameter of 4.2 in the workpiece. The screw (det. 3) of the conductor is attached to the table of the drilling machine. After installing the workpiece, a plate (det. 1) is placed on it, which is fixed with a hook (det. 4). The hook provides easy and fast fastening of the conductor plate.

Lesson developed by the teacher

Gorlovka general educational

wcolaI - II No. 35

Dushkina I. A.

Lesson #18 (No. 4 in Topic No. 13 "Reading and detailing assembly drawings")

The date …………

Class 9

Topic: practical work on the topic "Reading assembly drawings according to

plan"

Lesson Objectives:

Educational: to test the knowledge, skills and abilities of students in reading assembly drawings according to the given plan, to consolidate the skills of reading assembly drawings and writing records in a drawing font.

Educational: contribute to the education of diligence, accuracy, work culture.

Developing: contribute to the further development of memory, attention, eye; logical, analytical and spatial thinking.

Teaching aids, drawing tools, accessories and materials.

For the teacher:

textbook "Drawing.8 - 9kl." ed. VC. Sidorenko

training tables containing an image of assembly drawings of simple assembly units, writing a drawing font

didactic materials (cards - assignments) edited by E.A. Vasilenko

table "Reflection"

electronic version of tables, cards (if necessary equipment is available)

For students: A4 format in a cage, cards with tasks, drawing

accessories and tools.

Lesson type: control and correction of knowledge, skills and abilities

During the classes

1. Organizational stage:

Greetings

Organization of the workplace of students, issuance of cards with assignments, drawing tools, supplies and materials from the fund of the office for work in this lesson. Check readiness for the lesson.

Checking the attendance of students.

Filling out the class journal by the teacher

Announcement of the topic of the lesson.

2.Updating basic knowledge and checking homework.

The teacher visually checks homework

3. Motivation of educational activity.

Today we test your knowledge, skills and abilities in reading assembly drawings, taking into account the studied conventions and simplifications that you received in previous classes and in self-preparation for practical work. I hope that this will allow you to successfully complete today's practical work and start studying the topic "Detailing assembly drawings" in the next lesson.

Announcement of the goals and objectives of the lesson:

Today in class:

Students must independently read the assembly drawing according to the plan.

Make a technical drawing of the part specified in the task card

Identify shortcomings and gaps in knowledge for their correction and filling in home preparation for subsequent lessons

At the same time, we must be careful, think, analyze, imagine and not waste time

Success at work

4. Practical work. Formation of skills and abilities.

4.1. Issuance of individual cards - tasks 10 options (attached)

4.2. Answers to questions on the assignment, if any.

4.3. Independent work of students under the visual control of the teacher.

5. Summing up the lesson.

The teacher gives a general description of the learning activity in the lesson;

Collects works

Reflection: continue the sentence:

I didn't think that….

I will definitely…….

It seemed to me that…….

I did not like………

I think I need………

6. Homework:

Repeat the material on the topic "Reading assembly drawings"

At the request of the students, perform a creative task on the studied section (prepare an electronic presentation, make a crossword puzzle, a rebus - of your choice)

Application

Option number 1

Exercise 1.

Task 2.

Option number 2