Prefabrication for carburetor assembly and assembly

Contents

Introduction

1. Selection and correction of maintenance, R and D standards

1.1 Selection of initial standards of maintenance and repair mode

VAZ car

1.2 Adjusting Maintenance Standards

and repair

2. Technology of disassembly and assembly of car carburetor VAZ

2.1 Description of VAZ vehicle carburetor

2.2 Organization of disassembly and assembly works

2.3 Technology of disassembly-assembly of VAZ car carburetor

3. Design Part

3.1 Purpose of accessory

3.2 Principle of operation

3.3 Kinematic calculation of accessory

4. Occupational and environmental protection

4.1 Safety of carburetor section

4.2 Safety Regulations

4.3 Environmental Protection and Fire Safety

Conclusion

List of sources used

Application

Introduction

One of the most important problems facing road transport is improving the operational reliability of cars and reducing the cost of maintaining them. The solution to this problem, on the one hand, is provided by the automotive industry through the production of cars with great reliability and processability (repairability), on the other hand, by improving methods of technical operation of cars; increase of labor productivity, decrease of labour intensity of maintenance works and repair of cars; increase of their overhaul runs. This requires the creation of the necessary production base for maintaining the rolling stock in good condition, the widespread use of mechanization and automation of production processes, expansion of construction and improvement of road quality.

The constant increase in the number of cars in operation leads to pollution of the environment with harmful components of exhaust gases. At the same time, the failure of the power supply or ignition system of cars with carburetor engines causes an increase in the content of harmful components in the exhaust gases by 2-7 times. In addition, faulty or old cars exceed the permissible noise level by 15-20%. Finally, technically faulty

cars are the source of 4-8% of traffic accidents.

In recent years, there has been a tendency to complicate the design of cars (as a result of the installation of additional units, mechanisms and devices), favorably affecting productivity, comfort, economy and other properties, however, simultaneously causing an increase in labor costs for maintenance and repair.

Requirements for the reliability of vehicles are increased due to the increase in speeds and intensity of traffic, capacity, load capacity and capacity of cars, as well as the technological and organizational connection of road transport with serviced enterprises and other modes of transport.

The purpose of course design is to deepen, consolidate and systematize the knowledge set forth in the course of this discipline.

In this course work, the process of assembly-disassembly of the carburetor of the VAZ21083 engine will be developed.

2 Technology of disassembly and assembly of car carburetor VAZ-2108

2.1 Description of the car carburetor VAZ-2108

On the engines of the VAZ2108 car, carburetors of the Solex type are installed - emulsion type, two-chamber, with successive opening of throttle valves. The throttle valve drive is fur, cable. Carburetors have balanced float chamber, system for suction of crankcase gases, heating of throttle valve zone of the first chamber, starting device with mechanical drive, electromagnetic shut-off valve of idling. Engine 21083 is equipped with carburetor 210831107010.

Fuel is supplied to carburetor through strainer and needle valve. The latter maintains preset fuel level in float chamber.

The float chamber is two-section (this design reduces the effect of fluctuations in the fuel level during turns and rolls of the car on engine operation). Fuel is supplied from float chamber through main fuel jets (first and second chambers) to emulsion wells, where it is mixed with air passing through calibrated holes in upper part of emulsion tubes (main air jets). Fuel-air emulsion enters small and large diffusers of carburetor through sprayers.

The idling system takes fuel from the emulsion well, after the main fuel orifice of the first chamber. Fuel passes through the idling orifice (structurally combined with the idling solenoid shutoff valve), after which it is mixed with air from the channel from the idling air orifice and from the expanding part of the diffuser (for stable operation when switching to idling mode). The resulting emulsion is fed under the throttle valve through a hole closed by a quality screw. The number (number of revolutions) screw adjusts the value of opening of throttle valve of the first chamber at idle.

Modern carburetors, including those of the Solex type, are highly reliable and operate smoothly for a long time without any interference with the design.

The required conditions for stable and uninterrupted operation of the carburetor are the purity and correct adjustment of its elements, assemblies and systems. Therefore, through a certain mileage of the car, preventive measures must be carried out.

It is recommended to perform cleaning and adjustment work with a frequency of about 15 thousand km, which corresponds to the average annual mileage of the individual owner's car, and best of all - during preparation for the annual state technical inspection. Such periodicity is not a dogma and can vary widely depending on the operating conditions of the car. For example, with constant operation in a large city, the need for servicing the carburetor may arise with half the mileage, and if the car is used mainly for trips to the country in the summer, then the carburetor without maintenance can work completely normally and after a mileage of 30 thousand km.

To prevent sudden failures caused by damage to carburetor elements, the method of preventive complete disassembly with the replacement of wear elements (diaphragms, gaskets, O-rings, etc.) after diagnostics on special equipment is widely practiced at motor enterprises. In today's circumstances, it is unlikely that it would be appropriate for an individual owner to use this method permanently, both for material and time-consuming reasons.

Maintenance and repair of the carburetor is carried out without removing the carburetor from the engine or with removal.

Without removing the carburetor, wash its outer surfaces, a mesh fuel filter and a float chamber; cleaning the jets and other parts inside the carburetor from deposits; float mechanism, starter, idling system, carburetor drive are adjusted. These works are carried out either without disassembly of the carburetor, or with partial disassembly - remove the cover and elements of additional devices located outside.

2.2 Organization of disassembly and assembly works

Most operations to disassemble the carburetor can be performed without removing it from the car. The disassembly procedure can be arbitrary in many cases. Carburetor adjustment works are performed at TO-2 posts.

It is recommended to perform cleaning and adjustment work with a frequency of about 15 thousand km, which corresponds to the average annual mileage of the individual owner's car, and best of all - during preparation for the annual state technical inspection. Such periodicity is not a dogma and can vary widely depending on the operating conditions of the car.

To prevent sudden failures caused by damage to carburetor elements, the method of preventive complete disassembly with the replacement of wear elements (diaphragms, gaskets, O-rings, etc.) after diagnostics on special equipment is widely practiced at motor enterprises. In today's circumstances, it is unlikely that it would be appropriate for an individual owner to use this method permanently, both for material and time-consuming reasons. Maintenance and repair of the carburetor is organized both with the removal of the carburetor from the car and without removal.

3. Design Part

3.1 Purpose

In this course work there is an accessory for disassembly - carburetor assembly.

For car carburetor repair behavior, final determination of breakdowns of carburetor internal parts, it is necessary to perform its complete or partial disassembly. The worker must perform disassembly operations in a convenient position and have access to inaccessible places of the carburetor. The developed accessory makes it possible to realize these conditions, at the minimum cost of time to perform the necessary works

3.2 Principle of operation of the accessory

The principle of the stand is as follows: the worker, having removed the carburetor from the car, sets on the device. Attachment is performed by studs together with carburetor housing. Once the carburetor is secured, disassembly can be performed. Note here that bench can turn carburetor relative to transverse axis by required angle to more convenient position. For this purpose worm reduction gear is installed on the accessory.

Advantages of the stand: mobility, the ability to rotate the carburetor.

Disadvantages: complexity of manufacturing and maintenance.

Technical characteristics of the bench

Overall dimensions, mm:

length................................................................................. 341

width.................................................................... 250

height..................................................................... 260

Weight of kg:.................................................................................. 30

4 Occupational and environmental protection

4.1 Occupational safety at carburetor site

Working conditions and safety on the carburetor site depend both on the perfection of the machines used, the technology and the organization of production, and on the sanitary and hygienic situation surrounding the workers, that is, on the indicators of temperature, relative humidity, air speed and illumination in the production premises. Scientifically based painting of equipment and production premises contributes to an increase in labor productivity of up to 20%, a reduction in injuries by 3540% and a halving of production failures.

To prevent negative cases, it is necessary: to improve the culture of production, instruct workers on safety, work techniques, monitor compliance with safety rules, involve the public in solving labor protection issues, prevent technological process violations, monitor the serviceability of equipment, equipment and tools, do not clutter passages and driveways, monitor the safety of protective fences, provide working clothes.

4.2 Safety Regulations

When maintaining and repairing a car, safety measures are important.

It is forbidden to use a faulty tool during maintenance of the vehicle.

The necessary work with the units of the car should be carried out using lifting and transport mechanisms equipped with grips, guaranteeing the safety of the work. It is not allowed to lift and hang the car by towing tricks. When lifting and transporting units, it is impossible to be under raised parts of the car.

Before carrying out works it is necessary to:

- check the workwear, make sure that there are no hanging ends. Sleeves must be fastened or rolled above the elbow;

- check the locksmith, which must be strong and stable, correspond to the growth of the worker. Locksmiths must be serviceable, firmly fixed on the mop;

- prepare the workplace: to free up the necessary area for work by removing all foreign objects; ensure sufficient illumination;

- check serviceability of the tool, correctness of its sharpening and fuelling;

- when checking the tool, pay attention to the fact that the hammers have an even, slightly convex surface, are well fitted on the handles and fixed by a wedge; teeth must not have serrations on the working part and sharp ribs on the faces; filers are firmly mounted on handles;

- check serviceability of equipment, on which it is necessary to operate, and its fencing;

- before lifting of weights check serviceability of lifting devices

(blocks, jacks, etc.); all lifting mechanisms shall have reliable braking devices and the weight of the lifting load shall not exceed the lifting capacity of the mechanism. It is forbidden to stand and pass under the lifted load; Do not exceed the manual weight limits established by the current labour protection legislation for men, women, boys and girls.

During the work it is necessary to:

- firmly clamp the part or workpiece in the clutches, and during installation or removal, use caution, since the part can cause injury when falling;

- remove sawdust from the workpiece or workpiece only with a brush;

- when chopping metal with a tooth, work only in protective glasses. If under operating conditions it is impossible to use protective nets, then the cutting is carried out so that the cut off particles fly off in the direction where there are no people;

- do not use faulty devices during operations;

- prevent contamination of clothes with kerosene, gasoline, oil.

After completion of operation it is necessary to:

- remove the workplace;

- place tools, accessories and materials in appropriate locations.

4.3 Environmental Protection and Fire Safety

Since 1974, in the promising and current plans for the social and economic development of Russia there is a section,, Nature Protection. "

By the beginning of 1982, more than 30 standards for the protection of nature were created and implemented. In the fundamental standard for the management of industrial enterprises and production associations (GOST 24525.080), the function of environmental protection is put on a par with the implementation of the state plan.

The direct negative impact of cars on the environment is associated with emissions of harmful substances into the atmosphere, noise and various electromagnetic radiation.

The indirect impact of road transport on the environment is due to the fact that roads, parking lots, service enterprises occupy an increasingly large and annual increase in the area necessary for human life.

The main safety requirements in the workshops are local suction and general ventilation.

Fire - uncontrolled burning outside a special center, causing material damage. Large fires often take on the nature of a natural disaster and are accompanied by accidents with people. Fires in places of storage of flammable and combustible liquids and gases are especially dangerous.

Excluding the causes of fires is one of the most important conditions for ensuring fire safety at ATP. The company should organize timely fire training and training on the fire technical minimum. On the territory, in production, administrative, storage and auxiliary rooms it is necessary to establish a strict fire regime. Special smoking areas shall be reserved and equipped. Metal boxes with covers are provided for used wiping material. For storage of easily flammable and combustible substances, places are determined and permissible amounts of their one-time storage are established.