Worm Gear Design

Contents

Introduction

Motor selection and motor kinematic calculation

Calculation of capacities and transmitted torques on shafts

Strength calculations of gears

Design and inspection calculation of shafts

Geo-calculations of gears

Selection and check calculation of rolling bearings

Coupling selection and check calculation

Calculation of anchorages on shafts

Selection of lubrication system, lubricants and seals

Sizing Body Parts

Conclusion

List of used literature

Introduction

In all sectors of the national economy, production processes are carried out by machines and apparatus. Therefore, the level of the national economy is largely determined by the level of mechanical engineering.

The task of the designer is that, based on the considerations of the technical feasibility of the designed machine, be able to use engineering calculation methods that make it possible to achieve the task with the rational use of the resources allocated for its creation and use.

The course project is an important independent work of the student, covering the issues of calculating machine parts according to performance criteria, rational selection of materials contacting steam and lubrication systems in order to ensure the maximum possible efficiency and based on knowledge of a number of subjects: materials science, mechanics, material resistance, etc .

When performing a course project, the student successively goes from rational selection of the kinematic scheme of the mechanism through many variants of the solution to the implementation of the mechanical drive in the graphic material, while getting acquainted with existing structures, becoming involved in engineering creativity, understands the relationship of individual parts in mechanics and their functional purpose.

The goal of the project is to master and acquire the student skills in designing and calculating mechanical drives, to teach the correct and reasonable use of the obtained theoretical knowledge to solve specific engineering problems.

Selection of lubrication system, lubricants and seals

To reduce friction power losses and wear intensity of friction surfaces, as well as to prevent them from jamming, gouging, corrosion and better removal of heat of friction surfaces, the parts must have reliable lubrication.

Crankcase lubrication system is used. In the case of a reducer being filled in with oil so that in it it was shipped praktichesk all wreath of a worm wheel. When it rotates, the oil is carried away, sprayed, falls on the inner walls of the body, from where it flows into its lower part. Inside the housing, a suspension of oil particles is formed in the air, which covers the surface of the parts located inside the housing.

The lubricant is selected. The required viscosity of the oil depends on the contact voltage and the circumferential speed of the wheels. By certain speeds and contact stresses, we find the required kinematic viscosity and oil grade - industrial AND - 20A.

Bearings are lubricated with the same oil as other gear parts. Bearings, which are difficult to access, are lubricated with plastic lubricant.

During the operation of the transmissions, the oil is gradually contaminated with wear products. Over time, it ages, its properties deteriorate. Therefore, the oil must be periodically changed. For this purpose, a drain hole closed by a drain plug is provided in the housing.

During long-term operation, due to heating of oil and air, the pressure inside the housing increases, which leads to oil leaking through seals and joints. To avoid this, the interior of the housing is communicated with the external environment by installing the perfume at its upper points.

Sealing devices are used to prevent leakage of lubricating material from bearing assemblies, as well as to protect them from dust and moisture ingress from the outside. We use cuff seals. They have found widespread use in lubricating bearings with liquid oil. The cuff is installed with its open side inside the housing. In this case, good access of lubricating oil is provided to the working edge of the cuff.

Conclusion

During the course project on the topic: "Calculate and draw the mechanical drive," the following data were obtained: an electric motor of type 4A160M2U3 with a power of 18.5 kW, asynchronous, was selected. In terms of safety, the engine is closed. The drive is carried out using V-belt transmission with axial distance and speed

Also developed worm single-stage reduction gear:; The reduction gear case and cover are made of grey cast iron, which serve for placement of transmission parts in them, their coordination and protection against contamination.

During the course project, having gone from kinematic calculation to the implementation of the mechanical drive in the graphic material, I joined the engineering work. In the course design, calculations of gears, bearings, geometric parameters of parts and the gearbox housing were carried out. A sketched layout of the main parts and assemblies of the transmission mechanism and drive as a whole was made, the dimensions of the body parts were determined and part materials were selected depending on the working conditions, manufacturing technology and type of production.

As a result, I learned and acquired the skills of designing and calculating a mechanical drive, learned to correctly and reasonably apply the acquired knowledge to solve specific engineering problems.