Those who know the principle of operation of an internal combustion engine can easily guess what is going on inside the compressor. There is also a piston, and a valve system is also installed. The evaporated freon passes and is immediately heated by compression, then goes under pressure towards the condenser. After that, it is easily converted into a liquid state, giving energy, so that after it can go on a repeated cycle through a capillary expander.
The main task is to freon constantly circulated like blood through the veins. That is why often the compressor is also called the heart of the refrigerator. But they can be different, inverter and simple, that is, to list for a long time - there is little for this introduction. Let's look at the compressor device in more detail.
1 Classification of compressors in refrigeration equipment
- 1.1 Dynamic compressors
- 1.2 Reciprocating Compressors
- 1.3 Rotary compressors
- 2 Summarizing
Classification of compressors in refrigeration equipment
Here you need to say thanks to Bykov A.V. for an excellent guide to compressors for refrigerators 1992 editions.
You have naturally heard that in standard domestic refrigerators there are piston compressors, and you still think that Koreans, having developed in 1981 twin screw juicer design, really discovered something new? This is a complete misconception! Screw compressors have existed since 1878, it is from this time that rotors are used, which rotate towards each other to create pressure. Screw compressors in a refrigerator, as opposed to reciprocating compressors, have a number of advantages:
- Excellent compression ratioAs a rule, it is determined by the quality of manufacturing, processing of parts, exposure of specified dimensions, fit and tolerances. Simply put, you need high technology.
- Constant shaft torsion speed independent of system pressure. This gives all indicators of the screw refrigerating two-rotor compressor increased stability in various conditions.
- Possibility of smooth power adjustment the refrigerator by the usual variation of the torsion speed of the rotors. It is quite convenient in inverter refrigeration control systems.
- The specificity of the design is such that there are no parts that carry a high load.Due to this, the unit is quite durable. An oil injection is added to the steam chamber.
In addition, with respect to industry, there are a number of main advantages of screw double-rotor compressors, in contrast to reciprocating compressors:
- Smaller dimensions directly compressor refrigerator.
- The relatively low noise level, which makes it possible to avoid in some cases problems with the installation of the refrigerator.
- Low vibration of the refrigerator. As a result, you do not need to create a strong and heavy foundation.
There is only one drawback:
- Low efficiencyIn the case of the conversion of freon from one state to another directly inside the body of the refrigerator. This is due to the constant torsion speed of the shafts and the different levels of compression for this reason. The piston rotates while there is strength, and the screws grind, not paying attention to something. Naturally, when there is enough power.
Here are the simplest facts. But how does this equipment work, and what kind of compressors can be in a refrigerator? This class of equipment is divided into types and subtypes.
- Axial subtype;
- Subtype centrifugal.
- Crankshaft Subtype;
- Subtype translational.
- Rotary subtype: single rotor and two rotor.
- Subtype with rolling rotor.
- Subtype spiral.
- Subtype lamellar.
- Subtype rotary piston.
So, it is clear how many devices can be, and many of them have found their application.
Unlike bulk, these devices use the "living" power of the blades. If in the piston and their counterparts, the entire load is on rigid structures, then the work takes place at the expense of the fan. Who is familiar with ventilation systems and air conditioning devices already noticed similarities in the names. And it is quite logical: inside dynamic compressors there are two types of fans:
Most readers have already understood the meaning, but we still explain that:
- Centrifugal work due to the fact that every body that moves in a circle tries to exit a straight line from orbit.
- Axial fans - this is exactly what we use in the heat for blowing. Only this device is installed inside the nozzle to create pressure in the desired direction. Due to this environment moves under the influence of rotating blades.
The disadvantages of dynamic compressors are obvious: there is no way for them to get a good compression ratio, and, accordingly, it is difficult to create increased pressure. For example, refrigeration devices inject freon to 20–30 atm. and many say that this is not the limit. This is quite high data. But the design of dynamic compressors is relatively simple, which is good. Design requirements, on the contrary, are low, and this is also excellent.
The way of operation of the compressor of the refrigerator is very similar to the single-cylinder internal combustion engine. Inside the device is the same crankshaft, driven by an electric motor. But there is another design, it is more economical and more easily controlled by the inverter pulse generation system.
In this case, there is a certain rod with a piston at the end, which is located inside the wire coil. Passing current causes the system to make translational movementsIt is thanks to this that the refrigerator works. Today, such technologies are the best, and Koreans actively use them in their products, which is what instructive and good videos create.
In the working chamber there are 2 valves - consumable and supply. As a rule, they are on the walls. When the compressor is straight-through, the input is sometimes installed on the cylinder. But this design is not very common. The valve in the bottom of the piston increases the mass of the moving element, it is also difficult to provide the necessary bore holes. Therefore, now in the technique reciprocating plunger compressors are installed.
Two-rotor compressors are considered an absolute analogue of a twin-screw juicer. Here are just, as a rule, unequal helical spirals. The leading rotor is 4 protrusions with slightly rounded tops, under the slave made 6 hollows of the required profile. Both shafts are placed in a double cylindrical body and touch each other along the entire length. Rotation goes to meet.
Outlet and intake openings for freon, as a rule, are located on the diagonal:
- compressed gas is discharged at the end of the coils at the bottom;
- the refrigerant passes at the top of the rotors.
The design is made so that the spirals of the rotors are securely attached to the body. The rotation occurs in such a way that from the intake chamber of the air went out sideways (on different sides), grabbed by rotating shafts. On the first rotor of these portions 4, on the second 6. Rotating around the circumference, spirals are encountered as a result. Subsequent torsion leads to a strong compression of freon, under high pressure, it comes out.
To understand the beauty of this system, remember that twin-screw juicers have the greatest spin ratio, and they can grind even bones, when made of metal, without a large damage. This design of the refrigerator compressor makes it possible to create shock pressure, which is difficult to achieve in other cases.
Recall that the oil in the steam chamber of the refrigerator passes under the injection to reduce friction. However, this is not one reason. It is likely that the efficiency of the equipment depends directly on how tight the parts of the rotors are. Oil using surface tension forms a plug between the casing and the spirals. Thanks to this, pressure is increased without any effort. And accordingly, it is possible to reduce the speed of rotation to obtain the necessary indicators, reduce power consumption, reduce technical requirements for the quality and manufacture of parts the fridge.
The method of operation of the refrigeration compressor is far from screw, and probably in vain. But do not assume that pistons are everywhere. We have already said that most heat pumps have a scroll compressor. Here is the rotor and stator. These are two spirals, threaded into each other. With a circular movement of the rotor freon is strongly compressed and goes out.
So, we have considered what designs are and how the refrigeration compressor works. Now you know why you need a refrigerator compressor, and learned a considerable amount of knowledge in this area. This article explains, albeit briefly, what screw compressors are.