Analysis and synthesis of the core system - Course project - Theory of mechanisms and machines

Contents

SUMMARY

CONTENTS

INTRODUCTION

1 ASSIGNMENT FOR THE COURSE PROJECT

2 STRUCTURAL ANALYSIS OF THE MECHANISM

3 KINEMATIC ANALYSIS OF MECHANISM

3.1 Drawing up a plan of the provisions of the mechanism

3.2 Analytical study of mechanism kinematics

3.3 Geometric examination of mechanism kinematics

3.4 Construction of speed plans

4 DYNAMIC EXAMINATION OF THE MECHANISM

4.1 Reduced moment of resistance

4.2 Operation of reduced moment of resistance forces

4.3 Driving Forces Operation

4.4 Kinetic energy of driving forces

4.5 Kinetic energy of flywheel

4.6 Design calculation of flywheel

4.7 Determination of actual angular velocity of driving shaft

4.8 Determination of the law of movement of the initial link

5 POWER CALCULATION OF LEVER MECHANISM

5.1 Characteristics of forces acting on the mechanism links

5.2 Structural Group Power Calculation 4 -

5.3 Structural Group Power Calculation 2 -

5.4 Power calculation of structural group 1 -

LIST OF SOURCES USED

Summary

45 s., 30 il.,

bibliologist. list - 4 names.

1 A0 drawing sheet, 1 drawing sheet

A1 format, 1 A3 format drawing sheet

In the course design, the analysis and synthesis of the rod system was carried out.

All calculations are performed in the program "MathCad V15."

Drawings and diagrams are drawn using the program "Kompas V 14 SP2."

In drawing No. 1, movements, speeds and accelerations are graphically determined

the slider for 12 provisions of the mechanism and also for a standard position (at φ =55o).

Figure 2 shows the dynamic and power analyses of the mechanism,

a diagram of Wittenbaur,

Flywheel drawing is made on sheet No. 3.

Introduction

Scientific works on the theory, research and design of mechanisms are almost two hundred years old. Nascent engineering, rapidly developing in those years due to the intuition and individual abilities of talented singles - inventors and manufacturers, required a scientific assessment of the mechanisms created for their subsequent improvement in accordance with the requirements of production. Along with the task of creating engines as sources of mechanical movement, the urgent task of mechanizing the main technological operations arose. In the process of solving it, various mechanisms were created, with the mechanization of one main operation leading to the creation of one operating machine. This was the first step in the development of mechanical engineering.

Thus, already the first years of the development of mechanical engineering, the study of mechanisms was inextricably connected with solving practical problems.

This connection of theory with practice throughout its course and the development of mechanical engineering is a characteristic feature that determines the modern construction of the course of the theory of mechanisms and machines.

The second important step was the complex application of mechanisms for performing a certain technological process, which led to the creation of working machines. A working or production machine is called a single set of mechanisms used to mechanize the process and carry out a given program.

During the production process, the physical properties, shape state and position of the body to be treated are changed, which requires some useful work.

In addition to the class of working machines, there are transport machines and engines that convert a certain type of energy into mechanical work necessary to drive the working machine

The development of machines follows the path of combining the mechanisms of the engine, transmission and actuating. The latter mechanism is used for direct execution of certain operations of specified process. Each mechanism for performing technological operations has an actuating or working member.

The combination of these mechanisms forms a machine unit.

The design of a work machine usually begins with an analysis of the process plan, dividing it into separate operations. The aim is to create a rational interleaving or combining of the working operations performed by the machine mechanisms and to increase the use of total machine time, i.e., the proportion related to the periods of process operations, which leads to an increase in productivity.

Kinematic Mechanism Analysis

3.1 Drawing up a plan of the provisions of the mechanism

Before performing kinematic analysis, metric synthesis of the mechanism is carried out using the graphoanalytic method, that is, possible angular positions of links on a plane or in space are determined. The result of the metric synthesis is the constructed kinematic scheme of the mechanism and the position plan of the mechanism.

For construction we take scale factor of length μl = 0.005m/mm.

We select the position of the point O and from it we postpone the position of the point O5 (OO5=lOO5/μl - we similarly define other lengths for the construction ).

Through point O we draw a circle with radius AA. We take the position as the initial position, we take the position of the crank at an angle of 550, and by the method of ticks we draw a position plan.

Figure 1 shows a position plan in the extreme positions, in the 12 positions of the mechanism, and a mechanism plan in the reference position 550.

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