Design of the lever mechanism of the installation for compressive testing of samples

Contents

INTRODUCTION

1 STRUCTURAL ANALYSIS OF LEVER MECHANISM

1.1 Structural analysis of lever mechanism

1.2 Geometric synthesis of lever mechanism

1.3 Determination of kinematic characteristics of mechanism points motion

2 KINETOSTATIC (FORCE) ANALYSIS OF LEVER MECHANISM

2.1 Power analysis of group 3-2 slider-connecting rod

2.2 Force study of the initial link group

2.3 Determination of balancing force by means of "rigid lever"

N.E. Zhukovsky

3 DYNAMIC MECHANISM ANALYSIS

3.1 Diagram of given moments of moving forces or forces of useful resistance

3.2 Diagram of moving forces or forces of useful resistance

3.3 Diagram of kinetic energy increment ∆T

3.4 Diagram of reduced moment of inertia of JPR mechanism per cycle

3.5 Construction of energy mass diagram ∆T

3.6 Determination of moment of inertia of fly masses

3.7 Determination of main dimensions and weight of flywheel

CONCLUSION

LIST OF LITERATURE USED

APPENDIX A Kinematic analysis drawing of lever mechanism

APPENDIX B Power analysis drawing of lever mechanism

APPENDIX Drawing of dynamic analysis of lever mechanism

Introduction

The purpose of the course work is to conduct research and design of flat lever mechanisms of machines.

Flat lever mechanisms with lower pairs are used in many machines, in particular internal combustion engines.

When designing a crank-slide mechanism, any relationship between driving link movements can be provided.

The purpose of kinematic analysis of the mechanism is to establish a number of positions of all links of the mechanism, to determine linear velocities and accelerations of its points, as well as angular velocities and accelerations of the links of the mechanism.

The main task of kinetostatic (force) analysis of the mechanism is to study the influence of external forces on links, kinematic pairs and fixed supports, and to establish methods for reducing dynamic loads that arose during the movement of the mechanism. The results of this analysis are of great practical importance for calculating the strength of machine parts, for determining the required engine power.

Determining the moment of inertia of the flywheel by a given non-uniformity coefficient of machine travel is the main task of dynamic analysis of the mechanism.

1 structural analysis of lever mechanism

The task of determining the dimensions of the links of the mechanism according to its given structural scheme and kinematic conditions of the movement of the output (working) link is the main task of synthesizing (designing) the mechanism.

The purpose of kinematic analysis of the mechanism is to establish a number of positions of all links of the mechanism, to determine linear velocities and accelerations of the links of the mechanism.

The initial data for accomplishing the tasks are:

structural diagram of lever mechanism;

dimensions of some links;

dependencies between kinematic and geometric parameters of mechanism links;

the law of movement of the input link.

Kinetostatic (force) analysis of lever mechanism

The main task of kinematic analysis of the mechanism is to study the influence of external forces, gravity forces of the links, inertia forces and friction forces on the links of the mechanism, on the elements of the links, on kinematic pairs and fixed supports and to establish methods for reducing dynamic loads that arose during the movement of the mechanism. This task is called force analysis of the mechanism. The results of this analysis are of great practical importance for calculating the strength of the parts of the mechanism, for determining the power consumed for the operation of the mechanism, for calculating the wear of friction parts in kinematic pairs, etc.

Conclusion

In the course of this course work, I studied the general methods of structural, kinematic and dynamic analysis and synthesis of various mechanisms, the mechanics of machines.

The goal of the course work was also achieved, which consisted in studying general issues of research and design of mechanisms and general issues of machine mechanics, as well as in obtaining and developing skills for independently solving technical problems, and also sets the task of learning students certain methods and skills for working with reference literature.