Incomplete set of gear chevron drawings for course design

Introduction

The technical level of all branches of the national economy is largely determined by the level of development of mechanical engineering.

Improving operational and quality indicators, reducing the time of development and implementation of new machines, improving their reliability and durability are the main tasks of machine builders. One of the areas of solving these problems is improving the design training of students at higher educational institutions.

A large opportunity for improving the work of designers is provided by the use of computers, which allows you to optimize designs, automate a significant part of the design process.

The main goal of the course project on machine parts is the acquisition of design skills by students. While working on the project, it is necessary to perform calculations, rationally select materials and shapes of parts, striving to ensure their high efficiency, reliability and durability .

Gearbox Assembly Description

Prior to assembly, the inner surface of the gearbox housing is thoroughly cleaned and covered with oil-resistant paint.

Assembly is performed in accordance with gearbox assembly drawing, starting from shaft assemblies:

roller bearings pre-heated in oil to 80100˚C are fitted on driving shaft;

key is laid on shafts and wheel is pressed until stop against shaft collar; Then spacer bushing and roller bearings pre-heated are put on.

The assembled shafts are laid in the base of the body and in the side covers of the body, before covering the surfaces of the joint of the cover and the body with alcohol varnish. After that, a set of metal gaskets for adjustment is placed on the driving shaft. Cuffs are laid in grooves before installation of through covers. By turning the shafts there is no jamming of bearings (the shafts must be rotated by hand) and the covers are fixed with screws.

Then drain plug with gasket and rod oil indicator (probe) is screwed in; oil is poured into the body.

The assembled reduction gear is rolled on the bench according to the test program-method.

Lubrication of reduction gear box and bearings

Lubrication of hooks and bearings is used to protect against corrosion, reduce friction coefficient, reduce wear, remove heat and wear products from friction surfaces, reduce noise and vibration.

For general-purpose reducers, continuous lubrication with liquid oil by crankcase is used using a non-precision method (dipping). This method is used for gears used at circumferential speeds up to 12 m/s.

The choice of oil depends on the value of the calculated contact stress in the teeth and the actual circumferential speed of the wheels v. So (Table 10.29 [4]) at < 600 N/mm2 (we have = 417 N/mm2) and v = 2... 5 (we have v = 3.1) we use oil I-G-A-46 GOST 17479.487.

When the wheels are lubricated by dipping, the rolling bearings of the shaft supports are usually lubricated from the crankcase as a result of spraying oil with gear wheels, forming oil mist and spreading oil through the shafts. Reliable lubrication of bearings is possible at circumferential speeds of gears above 3 m/s. At lower speeds, plastic lubrication is used: solidol US-3, etc.

To measure the lubrication level in the gearbox housing, we use a rod oil indicator (probe), since it is convenient for inspection, has a simple design and is quite reliable.

We also provide a drain hole and a fragrance in the reducer.

Conclusion

The course design was carried out in accordance with the design assignment. Calculations of the chevron gearbox and open conical transmission were made, as well as other necessary calculations. The graphic part is made in accordance with calculations according to the recommendations of the training literature of the course "Machine Details."