Design and calculation of the friction clutch of the car.

Contents

Introduction

1 Purpose and requirements of the clutch

1.2 Analysis of existing clutch structures

1.3 Proposed design

2 Calculation of typical friction clutch elements

2.1 Selection of basic clutch parameters

2.2 Calculation of adhesion for wear and tear

2.3 Calculation of parts

2.3.1 Pressure disc

2.3.2 Cylindrical pressure spring

2.3.3 Calculation of clutch shaft

2.3.4 Driven disk hub

2.3.5 Torsional dampers

2.3.6 Clutch release bearing

2.3.7 Calculation of friction clutch drive

Conclusion

List of literature

Applications

Introduction

The section "Working Processes and Basics of Car Calculation" introduces us to the main requirements for the design of the car, develops skills in critical analysis and evaluation of new structures, studies the load modes of units and assemblies of automobile transport, methods for calculating them for strength, toughness, endurance, heating, and also provides information about part materials and heat treatment.

During the course project, we gain practical skills in design, calculation using the example of developing a new design of a car unit (system). Along with this, we learn to use mandatory standards for car design (GOST, industry standards, etc.), drawings, reference literature and other sources of technical information.

Solutions to specific problems reflected in the course project correspond to the modern level of automotive technology. During the course project, we critically analyze the existing design solutions, define and justify the layout and basic parameters of the designed assembly.

Purpose and clutch requirements

The clutch is a transmission unit that transmits torque in the ON state and has a device for its short-term shutdown. The clutch is designed for smooth touching of the car and short-term disconnection of the engine and transmission during gear shifting and prevention of impact on the transmission of large dynamic loads arising at transient modes.

Taking into account the purpose, the place in the transmission scheme of the car, the following specific requirements are imposed on the clutch:

1. Reliable transmission of torque from the engine to the gearbox. It is provided with the necessary margin of clutch moment (friction moment) at all modes of engine operation, preservation of pressure force within the required limits during operation;

2. Completeness of actuation, i.e. absence of slipping of clutch drive and driven parts, ensuring reliable transmission of engine torque. It is achieved in operation by the presence of a gap in the shutdown mechanism and preventing the lubricant from entering the friction surfaces;

3. Complete ("clean") shutdown, ensuring complete disconnection of the engine and transmission. It is achieved by the specified value of the operating stroke of the shutdown bearing and, accordingly, by the operating stroke of the clutch pedal;

4. Smooth actuation, which provides a given intensity of touching from the place of the car or after switching on the transmission. It is achieved by the design of the clutch, its drive and the pace of release of the pedal by the driver;

5. Protection of transmission and engine against G-loads and dynamic loads. It is achieved by optimal value of clutch moment margin, installation of torsional oscillation damper in it, special measures in design of driven disks;

6. Low moment of inertia of driven clutch parts, which reduces impact loads on wheel teeth during gear shifting;

7. Provision of normal thermal operation mode and high wear resistance due to intensive heat removal from friction surfaces;

8. Good balance in order to avoid "beats" and, accordingly, dynamic loads during clutch operation;

9. Easy and easy management, automation of switching on and off processes.

The clutches are also subject to general design requirements, such as: simplicity of the device, low labor intensity and ease of maintenance; minimum dimensions and mass; processability and low cost of production; repairability; low noise level.

1.3 Proposed design

The choice of design scheme involves decisions on the following issues: the type of clutch and drive, the number of driven disks, the type and number of pressure springs, the size of friction linings, the value of the clutch margin factor.

In modern cars, dry friction single- and two-disc clutches with non-automatic mechanical drive were most widespread. Other types of clutch are mainly used on special cars. Mechanical drive is used when placing the clutch pedal near the clutch. The hydraulic drive has a higher efficiency, providing better tightness of the cab (body), allows you to use an overhead pedal and is simpler in design with a significant removal of the pedal from the clutch and the overturning cockpit.

On the basis of the above, as well as a sufficiently high compliance with all clutch requirements, I choose a dry friction single-disc clutch with a hydraulic drive for the designed car.

The value of the margin coefficient is chosen depending on the type of car: for cars 1.3-1.75; single cargo 1.6-2.2.; cargo working with trailer 2.0-2.5; off-road vehicles working with a trailer 2.5-3.0. Large values ​ ​ are taken for clutches operating in difficult conditions (urban-type buses, motorized trucks, off-road vehicles, cars with low specific power).

For the designed adhesion I choose β = 2.0.

2 Calculation of typical friction clutch elements

Conclusion

In this course project, the already existing types of clutches were considered, the principles of their operation were set out. According to the task, the clutch type is more suitable for us, the clutch margin factor is chosen. On the basis of all the above, friction clutch parts such as a friction patch, a driven disk, and a pressure disk were designed. pressure spring, damper springs. Based on calculations and using literature, a clutch assembly was designed, which is presented in the A1 format drawing. Also, details of its component parts are made.

As a result of the project, extensive experience was gained in design, drawing, as well as in working with reference material