Course project on the discipline "Machine Parts"

Contents

Content.

1. Kinematic calculation

1.1 Selection of electric motor

3.Excise Design

3.1 Preliminary calculation of shaft diameters

3.2 Preliminary calculation of shaft lengths

3.3 Gear Design

3.3.1. High Speed Stage Wheel Design

3.3.2. Low Speed Gear Design

3.4 Worm Gear

3.4.1. Worm Wheel Crown Design

3.5 Design of Bearing Covers

4.4.1. Design of bearing cover for high-speed shaft

3.4.2. Intermediate Shaft Bearing Cover Design

3.4.3. Design of Bearing Cover for Slow Shaft

3.5 Chassis Design

3.6 Hatch Cover Design

4. Bearing calculation

4.2 Calculation of bearings on high-speed shaft

4.2.1. Definition of Bearing Loading Forces

4.2.2. Bearing Selection

4.2.3. Resource Calculation

4.2.4. Selection of bearing fit

4.3 Calculation of bearings on low-speed shaft

4.3.2. Bearing Selection

4.3.3. Resource Calculation

4.3.4. Selection of bearing fit

4.4 Calculation of bearings on intermediate shaft

4.4.1. Definition of Bearing Loading Forces

4.3.2. Bearing Selection

4.3.3. Resource Calculation

4.3.4. Selection of bearing fit

4.4.2. Bearing Selection

5. Shaft Strength Check

5.1 Calculation of high-speed shaft

5.2Development of intermediate shaft-worm strength:

5.3Development of output shaft strength:

6. Calculation of connections

6.1. Key connections

6.1.1. Key on high-speed shaft

6.1.2 Key on low-speed shaft

6.1.3 Key on intermediate shaft

7. Calculation of elastic coupling with steel rods

8. Elastic Coupling Selection

9. Selection of lubricants

9.1. Gear lubrication

9.2. Lubrication of bearings

10. List of used literature

2. Selection of gear box variant

When designing, the optimal parameters of the product should be selected in the best way, satisfying various, often contradictory requirements: lowest weight, size, cost, highest efficiency, required rigidity, reliability.

The use of computers for transmission calculations expands the amount of information used, allows you to make calculations with the search for the values ​ ​ of the most significant parameters: the method of thermal treatment or the materials used (permissible stresses), etc. The user needs to analyze the impact of these parameters on quality indicators and, taking into account the restrictions imposed, choose the best option.

The calculation is carried out in two stages. At the first, possible design solutions are found and the main quality indicators necessary for choosing a rational option are determined: mass of the mechanism, axial distance, wheel rim material, efficiency factor. When analyzing the results of the calculation, a rational option is chosen.

In the second step, all design parameters required for drawing release and the engagement forces required for shaft and bearing calculations are obtained for the selected option.

The weight of the product is most often taken as an optimality criterion. Since in this case the production of gearboxes is serial, it is desirable that the size and cost are minimal.

Initial data for worm gear calculation and parameters for option selection are given in Appendix 1.

After analyzing the results, we choose option No. 1, since it has a smaller mass and dimensions compared to variant No. 3.

Final calculation of transmission according to variant No. 1 is given in Appendix 2.