Principle of operation of the vacuum pump, device and features

The vacuum pump, the device, the principle of operation of which will be described below, is equipment that is used to pump and remove vapors or gases to a specified pressure level. The latter is also called the sanitary vacuum.

The development of vacuum technology starts in 1643. Then, for the first time, atmospheric pressure was measured. In the second half of the 19th century, mankind entered the technological stage of creating vacuum equipment and devices. This was due to the emergence of a mercury-piston pump, which occurred in 1862.

Principle of operation

The principle of the vacuum pump is that pumping is provided by changing the volume of the working chamber. Such volumetric pumps are used to obtain a preliminary vacuum, which is called forquake. This includes pumps:

• Rotational;
• Liquid-ring;
• Reciprocating.

The greatest popularity in vacuum technology was obtained by pumps of rotational type. If we are talking about high-vacuum pumps, then they include turbomolecular, steam-jet and steam-oil pumps. Molecules produce pumping by transferring the molecules of the gas motion from a solid, vaporous or liquid surface, the latter of which moves at high speed.

These include ejector, water jet, diffusion, molecular devices with the same direction of motion of surfaces and gas molecules. In addition, the class includes turbomolecular aggregates in which the motion of solid surfaces of injected gas occurs mutually perpendicular.

Additionally about the features of work

If you are interested in the principle of the vacuum pump, you should read this topic in more detail. This process is not as easy as it might seem at first glance. It should start with the fact that an analysis of the internal arrangement of such vacuum generating units indicates that almost all devices of this type operate on the principle of displacement, which can be compared with the principle of the action of volumetric pumps. They are used for pumping out the decomposition products of various mixtures and water.

The created vacuum, or rather its value, depends on the tightness of the space that arises from the operation of the pump mechanisms, among them it should be noted:

• Wheels;
• Special plates;
• Spools.

The principle of operation of the vacuum pump is reduced to the fact that the unit must fulfill two conditions, the first of which is expressed in lowering the pressure in the enclosed space, while the second is the fulfillment of the previous condition for a certain period of time. It is important that the sequence of conditions is maintained.

When the gas medium is absorbed by the equipment and the pressure is not reduced to the required value, a fore-vacuum apparatus will be required. This, in turn, will reduce the pressure of the gas medium. This principle assumes the possibility of sequential connection of pumps.

The principle of operation of the vacuum pump should assume the use of vacuum oil, which eliminates gas leakage through the gaps of rubbing parts. Thanks to the use of oil, it is possible to compact and completely cover the gaps. This oil acts as an excellent lubricant.

The device of the Roots pump

The principle of operation of the rotary vacuum pump has been described above, but you can find information about its device in this section. These pumps can be classified as displacing rotary vacuum pumps, which operate on a dry run. Among the main components of the equipment should be allocated:

• engine;
• A final branch pipe;
• Labyrinth seals;
• Bypass valve ;
• Oil level indicator;
• Fixed bearing;
• Free bearing;
• Suction chamber;
• Oil drainage;
• Outlet channel.

On the two lateral surfaces are the bearings of the rotor shaft. In order to ensure an uneven thermal expansion between the piston and the housing, they are designed as fixed bearings and sealing inner rings on opposite sides. Bearings are treated with oil, which is injected from the mudguards. The drive shaft is pulled out and insulated by the rings of the radiator shaft.

Rings are made of fluorine rubber, and then lubricated with sealing oil. The rings on the sleeve are necessary to protect the shaft, by the way, they can be replaced, if necessary. If a sealed seal is required from the outside, the equipment can be driven by a coupling with a glass and magnets.

BBH and the principle of its operation

The operating principle of the BBH vacuum pump is also based on the creation of a medium for suction of vapors and gases. As the main node of such devices is a round drum, in which there is a rotor with blades. When the rotor starts to rotate, the water is pressed against the walls of the drum by centrifugal force. As a result, a ring is formed.

The rotor is located away from the center, due to this under it a cavity is formed, which is divided into cells of different volume. When the cell is at the edge of the cavity, it has an insignificant volume, which is called the suction window. However, during rotation, the volume increases, and in this condition, gas is sucked. The volume becomes maximum, and the rotor makes another circle. From this it is clear that the principle of work in this case is based on centrifugal force.

Principle of functioning of the vacuum pump for the engine

The principle of operation of the vacuum pump of a diesel engine can interest the motorist. If you compare with gasoline engines, where there is a throttle and the possibility of creating a vacuum for use for different purposes, the diesel engine does not have a throttle, as described above. Therefore, in diesel engines, a pump is used to create a vacuum. It is complemented by an eccentrically mounted rotor with a movable plastic blade dividing the cavity into two parts.

Additional nuances

When the rotor rotates and the blade moves in it, one part of the cavity increases in volume, while the other part decreases. The air intake from the vacuum system takes place on one side of the suction, and after the air is forced out through the channel.

It is used to cool the components of the structure. Oil is fed through the channel, goes along the cylinder head, and then goes to the pump. Oil is used not only for lubrication, but also for sealing the blade in the working cavity. The drive is carried out from the crankshaft and camshaft, in the latter case the pump is combined with the fuel pump of the system.

Principle of operation of the water pump

The principle of the vacuum pump for water is the process of displacement. During operation, the water is pumped out as a result of changing the parameters of the working chamber. The volume of vacuum is related to the level of tightness of the working space, which is regulated, which allows to reduce or increase the pressure in a certain place to the desired value.

A water vacuum pump, the principle of operation of which can be of interest to the consumer, usually has a cylindrical shape. Inside is an impeller or shaft with a wheel that has special blades. The impeller acts as the main element. The wheel rotates in the body, which is filled with working fluid. As a result of rotational movements, the blades grasp water that spreads along the walls. There is a centrifugal force that provokes the appearance of a ring from the liquid. Inside, a free space is formed, called vacuum.

Features of the vacuum pump

Vacuum water pumps have certain characteristics, among them it should be noted:

• Low level of noise and vibration;
• High performance;
• High structural strength;
• Good flow rate and water injection;
• High starting pressure;
• Environmental friendliness.

An additional distinctive feature can be identified isothermal sealing. The unit excellently copes with evacuation of gases and vapors, and is also capable of removing liquids, doing this simultaneously. Quite often such equipment has a built in dirt separator.

Principle of operation of a plate rotary pump

Plate-rotor vacuum pumps, the principle of operation of which consists in a displacing action, is equipment with an oil seal. The system includes:

• The body;
• Blades;
• Centrically mounted rotor;
• entrance and exit.

The oil seal is installed on the exhaust valve, which is designed in the likeness of a vacuum relief valve. During operation, it is in the open state. The working chamber is located inside the case, and the rotor blades divide the chamber into two compartments, different in volume. Once the device is turned on, the gas will flow into the expansion chamber until it is blocked by the second blade.

What else you should know about the operation of the rotary pump

The gas inside is compressed until the exhaust valve under pressure is opened. If gas ballast is used, an external opening opens through which the gas is discharged into the suction chamber located on the front side. Such equipment has a second name - vacuum oil pump, the principle of operation of this device was described above. As a working fluid serves oil, which performs several functions. It lubricates the moving parts and fills the space under the exhaust valve. Fill with oil and narrow gaps between the exit and the entrance. The working fluid seals the gap between the working chamber and the blades, ensuring an optimal balance of temperature due to heat exchange.

Conclusion

Vacuum pumps can also be classified according to the physical principles of gas-binding and gas transfer operations. The latter transport particles or a working volume. Some versions of vacuum pumps assume molecular flow of the transferred substance, others - laminar flow. If we are talking about mechanical pumps, then they can be divided into molecular and volumetric ones.