Consumption ecology. Motor: World-famous for the production of cheap vehicles Indian company Tata released the world's first stock car with an engine that runs on compressed air.

Known worldwide for the production of cheap vehicles, the Indian company Tata has released the world's first mass-produced car with an engine that runs on compressed air.

Tata OneCAT weighs 350 kg and can travel 130 km on one supply of air compressed up to 300 atmospheres, while accelerating up to 100 km per hour.

According to the developers, it is possible to reach such indicators only with the tanks filled to the maximum, a decrease in air density in which will lead to a decrease in top speed.

To fill four carbon fiber cylinders located under the bottom of the car, 2 long and a quarter meter in diameter, each requires 400 liters of compressed air at a pressure of 300 bar. Moreover, Tata OneCAT can be refueled both at the compressor station (it will take 3-4 minutes) and from a household outlet. In the latter case, "pumping" with the help of a mini-compressor built into the machine will last three to four hours.

By the way, carbon fiber cylinders do not explode when damaged, but only crack, releasing air out.

Unlike electric vehicles, whose batteries have problems in terms of disposal and low efficiency of the charge-discharge cycle (from 50% to 70% depending on the level of charge and discharge currents), a compressed air car is quite cost-effective and environmentally friendly.

"Air fuel" is relatively cheap, if you translate it into a gasoline equivalent, it turns out that the car consumes about a liter per 100 kilometers.

Air vehicles usually do not have a transmission, as the air motor delivers maximum torque immediately - even when stationary. In addition, air engine practically no need for prevention: standard mileage between two technical inspections is 100 thousand km, and oils - a liter of oil is enough for 50 thousand kilometers (for ordinary car about 30 liters of oil would be needed).

Tata OneCAT has four-cylinder engine with a volume of 700 cubes and a weight of only 35 kg. It works on the principle of mixing compressed air with external, atmospheric air. This power unit recalls conventional engine internal combustion, but its cylinders are of different diameters - two small, drive, and two large, working. When the engine is running outside air is sucked into small cylinders, compressed there by pistons and heated, and then pushed into two working cylinders, where it mixes with cold compressed air coming from the tank. As a result, the air mixture expands and drives the working pistons, which in turn start crankshaft engine.

Since no combustion occurs in such an engine, only clean exhaust air is obtained at the output.

Calculating the total energy efficiency in the chain "refinery - car" for three types of drive - gasoline, electric and air, the developers found that the efficiency of the air drive is 20%, which is two times once again exceeds the efficiency of a standard gasoline engine and one and a half times - the efficiency of the electric drive. In addition, compressed air can be stored for future use using unstable renewable energy sources, such as wind turbines - then you can get even higher efficiency.

As the developers note, when the temperature drops to -20C, the energy reserve of the pneumatic drive decreases by 10% without any other harmful effects on its operation, while the energy reserve of electric batteries decreases by about 2 times.

In addition, the air exhausted into the air motor has a low temperature and can be used to cool the car interior on hot days. The owner of Tata OneCAT will have to spend energy only on heating the car during the cold season.

The Tata OneCAT, which is simple in design, was developed primarily for taxi use. published

One of the most significant problems of our time is the problem of pollution. environment. Every day, humanity emits huge amounts of carbon dioxide into the atmosphere. Every car that runs on an internal combustion engine harms our planet and makes the ecological situation even worse. Unfortunately, this is not all. The energy problem is no less acute, because oil reserves are not endless, gasoline prices are rising, and there is no reason to reduce them. Looking for alternative sources Fuel has been invented by many projects, but all of them are either too expensive or inefficient. Although one of them looks very promising. Judging by it, perhaps the new fuel of the future will be ... air!

Sounds fantastic, doesn't it? Is it possible for a car to run on air? Of course it is possible. But this air is not in the form in which we breathe it now - you need compressed air to move a car. Compressed and under high pressure, the air moves the pistons of the engine, and the car moves! After it has worked in the engine, the air returns to the atmosphere absolutely clean. The tank is enough for 200 kilometers, and the speed is also very impressive - up to 110 kilometers per hour! (Oddly enough, compressed air car engines have a very long history. The technology was first used back in the 1980s when Louis Mekarski patented his invention called the "pneumatic tram".) This car is not only completely environmentally friendly, it It will also significantly save money for its owner! One full charge compressed air will cost one and a half euros, and in a matter of minutes the car will be ready to travel again. One and a half euros are almost equal in price to two liters of gasoline. Calculate how much your car will drive on two liters - for sure the figure will be much less than 200 kilometers. Indeed, after small and simple calculations, daily refueling of a car with compressed air will cost at least 10 times cheaper! Inventor of this interesting concept, the indefatigable Frenchman Guy Negre, a former Formula 1 engineer, has been working on his project for more than a decade. The original engine layout, similar to a conventional internal combustion engine, made it possible to set the car in motion due to compressed air stored in cylinders. The idea was borrowed by Negr precisely from the design racing cars, in which a turbine is used for acceleration, fed by compressed air from a special cylinder. Guy Negre started with an original concept hybrid car, which at low speeds would move due to air, and at high speeds it would start a conventional internal combustion engine. This car was developed in the mid-90s, but the inventor decided to go even further. The result of 10 years of hard work has been several models that run exclusively on compressed air. At the heart of " air vehicle” Guy Negra is a motor that is very similar in design to a standard internal combustion engine. The engine has two working and two auxiliary cylinders. Warm air is sucked in directly from the atmosphere and additionally heated. Then it enters the chamber, where it mixes with compressed air cooled to -100 degrees Celsius. The air quickly warms up, increases sharply in volume and pushes the master cylinder piston, which drives the crankshaft. The first prototypes of a purely air car, created by the French from Guy Negra Motor Development International (MDI), were demonstrated in the early 2000s, and now, finally, it has come to the large-scale implementation of this remarkable development. tata motors company largest manufacturer cars in India, agreed with MDI to launch a licensed production of a small three-seat compressed air eco-vehicle. The MiniC.A.T model is equipped with a 90cc carbon fiber tank. m. compressed air. On one gas station with air, the car is able to travel from 200 to 300 km, with a maximum speed of 110 km / h. With the help of compressors installed at gas stations, it will be possible to refuel it in 2-3 minutes, while paying some 1.5 euros. Possible and Alternative option refueling with built-in compressor connected to a conventional network alternating current. To completely fill the “tank”, it will take 3-4 hours. Despite the fact that electricity is produced mainly by burning fossil fuels, an air eco-car is much more efficient than cars with internal combustion engines. It is superior in efficiency regular cars by 2 times, and electric vehicles - by 1.5. In addition, it is distinguished by the complete absence of harmful emissions, as well as extreme unpretentiousness in maintenance: due to the absence of a combustion chamber, the oil in the engine can be changed no more than every 50 thousand kilometers. Ecomobile MiniC.A.T will be produced in four modifications. They include a 3-seat passenger model, a 5-seat taxi, a minivan and light cargo pickup. The cars will sell for about £5,500 (about $11,000), which is very affordable. Tata plans to produce at least 3,000 “air cars” annually. They plan to sell them in Europe and India, but if the project gains popularity, possibly all over the world. The initiative of the Indians was supported by the American company Zero Pollution Motors, which announced the imminent withdrawal to American market cars powered by compressed air and built according to Guy Negre technology. Zero Pollution Motors plans to produce CityCAT vehicles with an engine option (6-cylinder, 75-horsepower Dual-Energy) that allows operation in two modes: simply on compressed air, or using a small amount of fuel to increase the temperature of the air in the cylinders and, accordingly, the power. In this mode, the car consumes about 2.2 liters of gasoline per 100 kilometers outside the city. CityCAT is a six-seater car with a spacious trunk. The body consists of fiberglass panels attached to an aluminum frame. The car will be able to drive 60 kilometers in the city on one supply of air, and outside the city with a small consumption of gasoline - 1360 kilometers. The speed of the car when working only on compressed air is 56 km / h, when using gasoline - 155 km / h. Estimated cost car - 17.8 thousand dollars. The first batch should enter the market in 2010. Let's hope that this is not the last step for the development of environmentally friendly modes of transportation. However, reviews of the "air car" in the media gradually turned from enthusiastic to skeptical. About them - below.

In 2000, numerous media outlets, including the BBC, predicted that in early 2002 mass production vehicles that use air instead of fuel.

The reason for such a bold statement was the presentation of a car called e.Volution at Auto Africa Expo2000, which took place in Johannesburg.

The astonished public was told that e.Volution can travel about 200 kilometers without refueling, while developing a speed of up to 130 km / h. Or within 10 hours of average speed 80 km/h. It was stated that the cost of such a trip would cost the owner of e.Volution 30 cents. At the same time, the machine weighs only 700 kg, and the engine - 35 kg. The revolutionary novelty was presented by the French company MDI (Motor Development International), which immediately announced its intention to start serial production of cars equipped with a compressed air engine. The inventor of the engine is the French engine engineer Guy Negre (Guy Negre), known as the developer starting devices for Formula 1 cars and aircraft engines. Negro said that he managed to create an engine that runs exclusively on compressed air without any impurities of traditional fuel. The Frenchman called his brainchild Zero Pollution, which means zero emission. harmful substances in atmosphere. The motto of Zero Pollution was "Simple, economical and clean", that is, the emphasis was placed on its safety and harmlessness to the environment. The principle of operation of the engine, according to the inventor, is as follows: “Air is sucked into a small cylinder and compressed by a piston to a pressure level of 20 bar. At the same time, the air is heated up to 400 degrees. Then hot air ejected into a spherical chamber. In the “combustion chamber”, although nothing is burned in it, cold compressed air from the cylinders is also supplied under pressure, it immediately heats up, expands, the pressure rises sharply, the piston of the large cylinder returns and transfers the working force to the crankshaft. You can even say that the "air" engine works in the same way as a conventional internal combustion engine, but there is no combustion here. It was claimed that car emissions were no more dangerous than carbon dioxide emitted by human breathing, the engine could be lubricated with vegetable oil, and the electrical system consisted of only two wires. It takes about 3 minutes to refuel such an air vehicle. Representatives of Zero Pollution said that to refuel the "air car" it is enough to fill the air tanks located under the bottom of the car, which takes about four hours. However, in the future it was planned to build "air filling" stations capable of filling 300-liter cylinders in just 3 minutes. It was assumed that sales of "air cars" will begin in South Africa at a price of about $10,000. There was also talk of building five factories in Mexico and Spain and three in Australia. More than a dozen countries have allegedly already received a license to manufacture the car, and the South African company has allegedly received an order for the production of 3,000 cars, instead of a planned pilot batch of 500 units. But after loud statements and general rejoicing, something happened. All of a sudden, everything was quiet and the “air car” was almost forgotten. The silence is all the more ominous because the official website of Zero Pollution went down some time ago. The reason is ridiculous: the page allegedly cannot cope with a huge flow of requests. However, the creators of the site in a vague form promise to “improve” it someday. The appearance of air cars on the roads was supposed to be a serious challenge to traditional transport. It is believed that environmental development was sabotaged automotive giants: foreseeing the approaching collapse, when they released gasoline engines no one will need them, they allegedly decided to “strangle the upstart in the bud”. This version is partly confirmed by Deutsche Welle: “Auto repair enterprises and oil concerns unanimously consider an air-powered car “unfinished”. However, this can be attributed to their bias. However, many independent experts are rather skeptical, especially since a number of large automotive concerns - for example, Volkswagen - already conducted research in this direction in the 70s and 80s, but then curtailed them due to complete hopelessness. Almost the same opinion is shared by environmentalists: “It will take a very long time to convince automotive manufacturers start production of "air" engines. Automobile companies have already spent a huge amount of money experimenting with electric cars, which have proven to be inconvenient and expensive. They don't need new ideas anymore." Zero pollution - engines with zero emission of harmful substances. In addition, they are lightweight and compact. But Deutsche Welle draws attention to the fact that in various publications "the description of the engine and circuit diagram his works are full of inaccuracies and errors, and, in addition, versions in different languages ​​not only differ considerably, but sometimes directly contradict each other. Almost every edition contains its own, different from others, technical specifications. The spread of numbers is so great that you involuntarily wonder: do they really refer to the same car? Another strange pattern is that with each subsequent publication, the parameters of the car improve: either the power will grow, then the price will fall, then the mass will decrease, then the capacity of the cylinders will increase. So, doubts here are quite appropriate and justified. However, the wait was not long. Probably, already in the coming year we will find out exactly what this compressed air engine developed by MDI is - a revolution in the automotive industry or in every sense of the word "inflated" sensation. Meanwhile, it is quite possible that in 2002 the intrigue with the "air car" will not be resolved. As a result of a long search for information on the Web, one more or less "live" site was discovered, which promises serial production revolutionary cars in 2003. By the way, in the process of searching, a lot of interesting things were found on the "air" topic. It is curious that at the international toy fair held in Nuremberg in February 2001, the Canadian company Spin Master offered buyers a model aircraft equipped with a compressed air engine. The mini tank can be inflated with any pump and the propellers take the original toy into the sky. In addition, the Internet has Commercial offer, addressed, apparently, to the government of Moscow. In this document, one metropolitan company invites officials to "read the proposal automotive company MDI (France) about the production of absolutely environmentally friendly and economical cars in Moscow”. There was also a suggestion by V. A. Konoshchenko, who reports on a car that he invented that runs on compressed air, attaching a description of the device. Also caught my eye is the invention of Rais Shaimukhametov - "Gardener", which is "driven by compressed air: under the hood small engine and serial compressor. Air rotates autonomously from each other two blocks (left and right) of eccentric rotors (pistons). The rotors in the block are connected by a caterpillar chain through the running wheels. As a result, there was a double impression: on the one hand, the story of the French “air car” is not fully understood, and on the other hand, a much clearer feeling that “air” transport has been used for a long time, and especially for some reason in Russia. And besides, from the century before last. There is evidence that a 33-meter submarine with an engine running on compressed air, designed by the self-taught I.F. Aleksandrovsky, was launched in the summer of 1865, successfully passed a series of tests, and only after that sank. THE NEGRO'S CAR IS AN EXPLOSIVE SENSATIONA startling idea - a car powered by compressed air - turned out to be a myth Sergey LESKOV Known oil reserves on Earth will last no more than 50 years. What are they trying to replace gasoline, which, among other things, is the main source of air pollution in big cities. And liquefied natural gas, and all kinds of synthesized gases and liquids, and even alcohol. For a long time, hopes were pinned on an electric car, but it specifications low, and the utilization of the energy source turned out to be a problem for the environment. And here is a new, dumbfounding idea - a compressed air car. French engineer Guy Negre made a name for himself in the automotive world with his starters for Formula 1 cars and aircraft engines. There are 70 patents in his design dossier. This suggests that the Negro is not a self-taught one of those who annoy all the automobile firms of the world with their discoveries. A few years ago, the respected Negro created the company MDI (Motor Development International), which was engaged in the development of compressed air engines. The first reaction of any expert is nonsense, whim and nonsense again. But back in 1997, in Mexico, the parliamentary commission on transport became interested in this development, experts visited the factory in Brignole and signed an agreement to gradually replace all 87,000 taxis in Mexico City, the most gnawed capital in the world, with cars with a clean “exhale”. Two years ago, at the Auto Africa Expo 2000, a concept car created by the Negra team called e was presented. Revolution. As promised, he used compressed air as fuel. In Johannesburg, on a wave of public interest, the start of serial production of a miracle car with a Zero Pollution engine was announced in 2002. In South Africa, it was supposed to make 3 thousand e. Revolution. The appointed year in the yard. Where is the "air car"? There are many publications on this topic, but the characteristics jump, as if it were not about technology, but about an Arabian stallion. If we average all the protocols, then the following portrait will come out: e. Volution weighs 700 kg, Zero Pollution motor weighs 35 kg. The car can travel 200 km without refueling. The maximum speed is 130 km/h. At a speed of 80 km / h, it can move for 10 hours. Estimated price - 10 thousand dollars. It takes energy to pump air into cylinders, and power plants are also a source of pollution. The authors of the project calculated the efficiency in the chain "refinery - car" for gasoline, electric and air engines: 9, 13 and 20%, respectively. That is, the "air vent" is in the lead by a noticeable margin. The filling itself takes about 4 hours, and the cylinders are hidden under the bottom. The principle of operation of the "air vent" does not differ from the internal combustion engine. No, due to the lack of fuel, only the combustion itself. There are no, in addition, ignition systems, fuel injection, gas tank. The air in the cylinders is under pressure of 200 atmospheres. The idea of ​​the designers is as follows: part of the exhaust is sucked into the small cylinder and compressed by the piston to a pressure of 20 atmospheres. Hot air up to 400 degrees is pushed into the chamber, which is an analogue of the combustion chamber. It is supplied with compressed air from cylinders. It heats up - and as a result, the cylinder piston moves, transferring the working force to the crankshaft. As we approach the announced release date, the discrepancies in publications on this topic are becoming more noticeable. It seems that Guy Negro's team is facing serious technical problems. To clarify the situation, Izvestia-Nauka turned to the most authoritative specialists in our country from the State scientific center"Research Automotive and automotive institute(NAMI)". - We calculated the duty cycle of this engine, - said Vladislav Luksho, head of the NAMI gas-cylinder equipment department. - This is another attempt to deceive the fundamental laws of nature, to slip past the rules of thermodynamics. This idea can be developed: to force the driver to pump air with his feet. The idea of ​​​​an engine in compressed air is absurd, because its efficiency is very low.The energy obtained from mechanical compression per kilogram of weight is 20-30 times inferior to chemical energy hydrocarbon fuel. Gasoline has no competitors. Only nuclear energy has higher figures. This e . Volution will only be able to travel short distances, like air powered toys fly. A skeptical attitude towards a compressed air engine does not mean at all, NAMI experts are sure of this, that attempts to find an alternative to a gasoline engine are doomed. It has already been possible to achieve tolerable characteristics in gas engines on propane-butane, which are only 1.5 times inferior to a gasoline engine in terms of heat transfer of fuel. In continuation of the precepts of Chonkin's friend Gladyshev, efforts are being made to master the engine on biogas, which is obtained from all sorts of garbage. Hydrogen has great prospects, and its uses are very diverse - from additives to gasoline to liquefaction or use in the form of compounds with metals (hydrides). According to latest developments NAMI, it is better not to burn hydrogen: it reacts in the fuel element, electricity, which is converted into mechanical energy. Another option is alcohol, which is energetically "stronger" than gas, although "weaker" than gasoline. Alcohol-powered engines have become widespread in Brazil. True, in Russia it is not worth talking about the introduction of this design - it's just stupid.

Developed by the French Motor Company Development International (MDI) called the AIRPod is powered by compressed air. Although it has been produced since 2009, for a long time she evoked in everyone (with the possible exception of environmentalists) only an indulgent smile. Indeed, initially it could only be operated in a warm climate: the pneumatic propeller engine developed in the early 1990s did not start when low temperatures. And although today a compressed air heating system has already been developed that expands the geography of the AIRPod, it can only be purchased in Hawaii (US state).

road show

In the spring of 2015, the independent company ZPM (Zero Pollution Motor - “Zero Pollution Motors”) held a public road-show in prime time on the American ABC television channel - a presentation to attract investors (literally translated into Russian as “road show”). ZPM bought the right to manufacture and sell the new AIRPod model from the French - so far only in Hawaii, chosen as the "launch market".

Presented the project of a plant for the production of environmentally friendly clean cars two shareholders of ZPM are the famous American singer Pat Boon (his career peaked in the 1950s) and film producer Eitan Tucker (Shrek, Seven Years in Tibet, etc.). They offered potential investors (so-called "business angels") a 50% stake in ZPM for $5 million.

Investors were in no hurry to shell out. At the same time, Robert Herjavec, the owner and founder of the Canadian IT company Herjavec Group, who was considered the most promising of them, said that he was interested in AIRPod sales not in one single state, but throughout the United States. So now the ZPM management is negotiating with the French to expand the sales territory.

At the beginning of the century, numerous media prophesied that the mass production of cars using air instead of fuel was about to begin.

The reason for such a bold statement was the presentation of a car called e.Volution at the Auto Africa Expo-2000 exhibition, which took place in Johannesburg. The astonished public was told that e.Volution can travel about 200 kilometers without refueling, reaching speeds of up to 130 km / h. Or for 10 hours at an average speed of 80 km/h. It was stated that the cost of such a trip would cost the owner 30 cents. At the same time, the machine weighs only 700 kg, and the engine - 35 kg.
The revolutionary novelty was presented by the French company MDI, which immediately announced its intention to start serial production of cars equipped with a compressed air engine. The inventor of the engine is the French engine engineer Guy Negre, known as the developer of starting devices for Formula 1 cars and aircraft engines.
The inventor stated that he managed to create an engine that runs exclusively on compressed air without any impurities of traditional fuel. The Frenchman called his brainchild Zero Pollution, which means zero emissions of harmful substances into the atmosphere.
The motto of Zero Pollution was "Simple, economical and clean", that is, the emphasis was placed on its safety and harmlessness to the environment. The principle of operation of the engine, according to the inventor, is as follows: “Air is sucked into a small cylinder and compressed by a piston to a pressure level of 20 bar. At the same time, it warms up to 400 degrees. The hot air is then pushed into the spherical chamber. Cold compressed air from the cylinders is also supplied to the “combustion chamber” under pressure, it immediately heats up, expands, the pressure rises sharply, the piston of the large cylinder returns and transfers the working force to the crankshaft. You could even say that an “air” engine works in the same way as a conventional internal combustion engine, only there is no combustion here.”
It was claimed that car emissions were no more dangerous than carbon dioxide emitted by human breathing, the engine could be lubricated with vegetable oil, and the electrical system consisted of only two wires. It was planned to build "air filling" stations capable of filling 300-liter cylinders in just three minutes. It was assumed that sales of "air cars" will begin in South Africa at a price of about 10 thousand dollars.
But after loud statements and general rejoicing, something happened. All of a sudden, everything was quiet, and the "air car" was almost forgotten. The reason is ridiculous: the page on the Internet supposedly cannot cope with the huge flow of requests.
It is believed that the environmentally friendly development was sabotaged by the automotive giants: foreseeing the impending collapse, when no one would need the gasoline engines they produce, they allegedly decided to strangle the upstart in the bud.
However, many independent experts are rather skeptical, especially since a number of large automotive concerns, for example, Volkswagen, were already conducting research in this direction in the 70-80s, but then curtailed them due to complete hopelessness. Car companies have already spent huge amounts of money experimenting with electric cars, which have proven to be inconvenient and expensive.
However, the wait was not long. Probably, already in the coming year we will find out exactly what this compressed air engine developed by MDI is - a revolution in the automotive industry or in every sense of the word an inflated sensation.
There is a commercial offer on the Internet, apparently addressed to the Moscow government. In this document, one metropolitan company invites officials "to get acquainted with the proposal of the automobile company MDI on the production of absolutely environmentally friendly and economical cars in Moscow."
Of interest is also the invention of Rais Shaimukhametov - a “gardener”, which is “driven by compressed air: under the hood is a small engine and a serial compressor. Air rotates autonomously from each other two blocks (left and right) of eccentric rotors (pistons). The rotors in the block are connected by a caterpillar chain through the running wheels.
As a result, there was a double impression: on the one hand, the story with the French “air car” is not fully understood, and on the other hand, a much clearer feeling that “air” transport has been used for a long time, and especially for some reason in Russia. And besides, from the century before last.

Drive units >

Pneumatic motors (pneumatic motors)

Pneumatic motors, they are also pneumatic motors, are devices that convert the energy of compressed air into mechanical work. In a broad sense, the mechanical operation of an air motor is understood as linear or rotary motion - however, air motors that create linear reciprocating motion are more often called pneumatic cylinders, and the concept of "air motor" is usually associated with shaft rotation. In turn, rotary air motors are divided, according to the principle of their work, into bladed (they are also lamellar) and piston - Parker produces both types.

We think that many visitors to our site are no worse than we are familiar with what an air motor is, what they are, how to select them and other issues related to these devices. Such visitors would probably like to go directly to technical information about the pneumatic motors we offer:

• Series P1V-P: radial piston, 74...228 W
• Series P1V-M: plate, 200...600 W
• Series P1V-S: lamellar, 20...1200 W, stainless steel
• Series P1V-A: lamella, 1.6...3.6 kW
• Series P1V-B: lamella, 5.1...18 kW

For our visitors who are not so familiar with pneumatic motors, we have prepared some basic information on them for reference and theoretical nature, which, we hope, may be useful to someone:

Air motors have been around for about two centuries, and are now quite widely used in industrial equipment, hand tool, in aviation (as starters) and in some other areas.

There are also examples of the use of pneumatic motors in the construction of compressed air vehicles - first at the dawn of the automotive industry in the 19th century, and later, during the new interest in "non-oil" car engines since the 80s of the XX century - however, unfortunately, the latter type of application still seems unpromising.

The main "competitors" of air motors are electric motors, which claim to be used in the same areas as pneumatic motors. The following general advantages of pneumatic motors over electric ones can be noted:
- pneumothorax takes up less space than an electric motor corresponding to it in terms of basic parameters
- the pneumatic motor is usually several times lighter than the corresponding electric motor
- air motors withstand without problems high temperature, strong vibration, impacts and other external influences
- most air motors are fully suitable for use in hazardous areas and are ATEX certified
- pneumatic motors are much more tolerant to starts/stops than electric motors
- maintenance of pneumatic motors is much easier than electric ones
- air motors have the ability to reverse as standard
- air motors are, in general, much more reliable than electric motors - due to the simplicity of design and a small number of moving parts

Of course, despite these advantages, quite often, nevertheless, the use of electric motors is more efficient both from a technical and economic point of view; however, where a pneumatic actuator is still used, this is usually due to one or more of its advantages listed above.

The principle of operation and device of a vane air motor

The principle of operation of the vane air motor
1 - rotor housing (cylinder)
2 - rotor
3 - shoulder blades
4 - spring (pushing the blades)
5 - end flange with bearings

We offer air motors of two types: piston and lamellar (they are also bladed); at the same time, the latter are simpler, more reliable, perfect and, as a result, more common. In addition, they are usually smaller than reciprocating air motors, which makes them easier to install in the compact housings of the devices that use them. The principle of operation of a vane electric motor is practically the opposite of that of a vane compressor: in a compressor, the supply of rotation (from an electric motor or internal combustion engine) to the shaft causes the rotor to rotate with blades emerging from its grooves, and thus reducing the compression chambers; in a pneumatic motor, compressed air is supplied to the blades, which causes the rotation of the rotor - that is, the energy of compressed air is converted in the pneumatic motor into mechanical work (rotational movement of the shaft).

A vane air motor consists of a cylinder-case in which a rotor is placed on bearings - moreover, it is not placed directly in the center of the cavity, but with an offset relative to the latter. Slots are cut along the entire length of the rotor, into which blades made of graphite or other material are inserted. The blades are pushed out of the grooves of the rotor by the action of springs, pressing against the walls of the housing and forming a cavity between its own, housing and rotor surfaces - a working chamber.

Compressed air is supplied to the input of the working chamber (it can be supplied from both sides) and pushes the rotor blades, which, in turn, causes the latter to rotate. Compressed air passes in the cavity between the plates and the surfaces of the body and rotor to the outlet, through which it is released into the atmosphere. In vane air motors, the torque is determined by the surface area of ​​the blades subjected to air pressure and the level of this pressure.

How to choose an air motor?

n	speed
M	torque
P	power
Q	CW consumption
	Possible mode of operation
	Optimum operating mode
	High wear (not always)

For each air motor, it is possible to draw a graph showing torque M and power P, as well as compressed air consumption Q, as a function of rotational speed n (an example is shown in the figure on the right).

If the motor is idle or freewheeling with no load on the output shaft, it will not develop any power. Usually, the maximum power is developed when the engine is braked to about half of its maximum rotational speed.

As for the torque, in the free rotation mode it is also equal to zero. As soon as the engine starts to decelerate (when a load is applied), the torque begins to increase linearly until the engine stops. However, it is impossible to specify the exact value of the starting torque - for the reason that the blades (or pistons of a piston air motor) can be in different positions when it is completely stopped; always indicate only the minimum starting torque.

At the same time, it should be noted that the wrong selection of a pneumatic motor is fraught not only with the inefficiency of its operation, but also with greater wear: high speeds, the blades wear out faster; on low speeds at high torque, transmission parts wear out faster.

Conventional selection: need to know torque M and speed n

The usual approach to air motor selection is to begin by establishing the torque at some specific desired speed. In other words, to select a motor, you need to know the required torque and speed. Since, as we noted above, maximum power is developed at about ½ of the maximum (free) speed of the air motor, ideally, you should choose an air motor that shows the required speed and torque at a power value close to maximum. For each unit there are corresponding graphs to determine its suitability for a particular use.

Little hint: in general, you can choose an air motor that, when maximum power provides slightly more speed and torque than required, and then adjust them by adjusting the pressure with a regulator-regulator and / or the compressed air flow with a flow restrictor.

If the moment of force M and the speed n are not known

In some cases, the torque and speed are not known, but the required speed of the movement of the load, the moment of the lever (radius vector, or, more simply, the distance from the center of application of force) and the power consumption are known. Based on these parameters, the torque and speed can be calculated:

First, although this formula does not directly help in calculating the required parameters, let's clarify what is power (it is the rotating force in the case of air motors). So, power (force) is the product of mass and free fall acceleration:

Where
F - desired power [N] (remember that ),
m - mass [kg],
g - free fall acceleration [m/s²], in Moscow ≈ 9.8154 m/s²

For example, in the illustration on the right, a 150 kg weight is suspended from a drum mounted on the output shaft of an air motor. There is a case on Earth, in the city of Moscow, and the acceleration of free fall is approximately 9.8154 m / s². In this case, the force is approximately 1472 kg m/s², or 1472 N. Once again, this formula is not directly related to our proposed methods for selecting air motors.

Torque, also known as moment of force, is the force applied to give an object rotation. The moment of force is the product of the rotating force (calculated using the formula above) and the distance from the center to the point of its application (the moment of the lever, or, more simply, the distance from the center of the air motor shaft to, in this case, the surface of the drum mounted on the shaft). We calculate the moment of force (it is also rotating, it is also torque):

Where
M - desired moment of force (torque) [Nm],
m - mass [kg],
g - free fall acceleration [m/s²], in Moscow ≈ 9.8154 m/s²
r - lever moment (radius from center) [m]

For example, if the diameter of the shaft + drum is 300 mm = 0.3 m, and, accordingly, the moment of the lever = 0.15 m, then the torque will be approximately 221 Nm. Torque is one of required parameter for air motor selection. According to the formula above, it can be calculated based on the knowledge of the mass and moment of the lever (in the vast majority of cases, differences in the acceleration of free fall can be neglected due to the rarity of the use of pneumatic engines in space).

The rotational speed of the rotor of an air motor can be calculated by knowing the speed forward movement load and lever moment:

Where
n - desired rotation speed [min -1 ],
v - translational speed of the load [m/s],
r - lever moment (radius from center) [m],
π - constant 3.14
A correction factor of 60 is included in the formula to convert revolutions per second to the more readable and more widely used revolutions per minute in technical documentation.

For example, with a translational speed of 1.5 m/s and the lever moment (radius) of 0.15 m suggested and in the previous example, the required shaft speed would be approximately 96 rpm. The speed of rotation is another parameter necessary for the selection of an air motor. According to the formula above, it can be calculated, knowing the moment of the lever and the speed of the translational movement of the load.

Where
P - required power [kW] (remember that ),
M - moment of force, also known as torque [N m],
n - rotation speed [min -1 ],
9550 - constant (equal to 30/π to convert speed from radians/s to revolutions/min, multiplied by 1000 to convert watts to kilowatts, more readable and more common in technical documentation)

For example, if the torque is 221 N·m at a rotation speed of 96 min -1 , then the required power will be approximately 2.2 kW. Of course, the reverse can also be derived from this formula: to calculate the torque or speed of rotation of the shaft of a pneumatic motor.

Transmission types (reducer)

As a rule, the shaft of the air motor is connected to the recipient of rotation not directly, but through a transmission-reducer integrated into the design of the air motor. Gearboxes are different types, the main of which are planetary, helical and worm.

Planetary reductor

Planetary gears are characterized by high efficiency, low inertial moment, the possibility of creating high gear ratios, as well as small dimensions in relation to the generated torque. The output shaft is always in the center of the body planetary gear. Parts planetary gear are lubricated with grease, which means that an air motor with such a gearbox can be installed in any desired position.
+ small installation dimensions
+ freedom in choosing the installation position
+ simple flange connection
+ low weight
+ output shaft is in the center
+ high work efficiency

Helicoidal gearbox

Helicoidal transmissions are also highly efficient. Several reduction stages allow high gear ratios to be achieved. Mounting convenience and flexibility is facilitated by the central location of the output shaft and the ability to mount the air motor with a helicoidal reducer both on the flange and on the racks.

However, such gearboxes are lubricated by splash oil (there is a kind of "oil bath" in which the moving parts of the gearbox must always be partially immersed), and therefore, the position of an air motor with such a transmission must be determined in advance - with this in mind, will be determined and the correct amount of oil to be filled into the transmission and the position of the fill and drain fittings.
+ high efficiency
+ easy installation via flange or studs
+ relatively low price
- the need to plan the installation position in advance
- higher weight than planetary or worm gears

Worm gear

Worm gears They are distinguished by a relatively simple design, based on a screw and a gear, due to which, with the help of such a gearbox, high gear ratios can be obtained with small overall dimensions. However, the efficiency of a worm gear is much lower than that of a planetary or helical gear.

The output shaft is directed at an angle of 90° with respect to the air motor shaft. The installation of an air motor with a worm gear is possible both through a flange and on racks. However, as in the case of helicoidal gears, it is somewhat complicated by the fact that worm gears, like helical ones, they also use oil splash lubrication - therefore, the installation position of such systems also needs to be known in advance, because. it will affect the amount of oil to be filled into the gearbox, as well as the position of the fill and drain connections.
+ low, in relation to the gear ratio, mass
+ relatively low price
- relatively low efficiency
- you need to know the installation position in advance
+/- the output shaft is at an angle of 90° to the air motor shaft

Air Motor Adjustment Methods

The table below shows the two main ways to regulate the operation of air motors:

Flow control The main method for regulating the operation of pneumatic motors is to install a compressed air flow regulator (flow limiter) at the inlet of a single-stroke motor. Where the motor is intended to be reversed and speed must be limited in both directions, regulators with bypass lines should be installed on both sides of the air motor. Feed or output limitation on 1-way motor Feed limit on reverse motor Reverse motor output limitation When regulating (limiting) the supply of compressed air to the pneumatic motor, while maintaining its pressure, the free rotation speed of the rotor of the pneumatic motor drops - while maintaining, however, full pressure compressed air to the surface of the blades. The torque curve becomes steeper: torque curve This means that at low speeds, full torque can be obtained from the air motor. However, this also means that at the same rotational speed, the motor develops less torque than it would develop with a full volume of compressed air.

Pressure regulation The speed and torque of the air motor can also be controlled by changing the pressure of the compressed air supplied to it. To do this, a pressure reducer-regulator is installed on the inlet pipeline. As a result, the motor constantly receives an unlimited amount of compressed air, but at a lower pressure. At the same time, when a load appears, it develops a smaller torque on the output shaft. Pressure regulation Pressure regulation Reducing the compressed air input pressure reduces the torque generated by the motor when braking (appearing a load), but also reduces the speed.

Control of operation and direction of rotation

A pneumatic motor works when compressed air is supplied to it, and when compressed air exits it. If it is required to ensure the rotation of the air motor shaft in only one direction, then the compressed air supply must be provided only to one of the pneumatic inputs of the unit; accordingly, if it is necessary that the shaft of the air motor rotates in two directions, then it is necessary to provide for the alternation of the compressed air supply between both inputs.

Compressed air is supplied and removed by means of control valves. They can be different according to the method of activation: the most common valves with electric control(electromagnetic, they are also solenoid, the opening or closing of which is carried out by applying voltage to an induction coil that retracts the piston), pneumatically controlled (when the signal to open or close is given by supplying compressed air), mechanical (when opening or closing is caused mechanically , by automatically pressing a certain button or lever) and manual (similar to mechanical ones, except that the valve is opened or closed directly by a person).

We see the simplest case, of course, with one-way pneumatic motors: for them, it is only necessary to provide compressed air to one of the inputs. There is no need to control the output of compressed air from the other pneumatic connection of the air motor in any way. In this case, it is sufficient to install a 2/2-way solenoid valve or another 2/2-way valve at the compressed air inlet to the air motor (recall that the design "X/Y-way valve" means that this valve has X ports through which the working medium can be supplied or removed, and Y positions in which the working part of the valve can be located). The figure on the right, however, shows the use of a 3/2-way valve (once again, in the case of single-way air motors, it does not matter which valve to use - 2/2-way or 3/2-way). In general, the figure on the right sequentially, from left to right, schematically shows following devices: shut-off valve, compressed air filter, pressure regulator, 3/2-way valve, flow regulator, air motor.

In the case of double-sided engines, the task is slightly more complicated. The first option is to use one 5/3-way valve - such a valve will have 3 positions (stop, forward stroke, reverse) and 5 ports (one for compressed air inlet, one for compressed air supply to each of the two pneumatic connections of the air motor, and one more for compressed air outlet from each of the same two connections). Of course, such a valve will also have at least two actuators - in the case of, for example, a solenoid valve, these will be 2 induction coils. The figure on the right shows in sequence, from left to right: a 5/3-way valve, a flow regulator with a built-in check valve (to allow compressed air to escape), an air motor, another flow regulator with a check valve.

An alternative option for controlling a two-way air motor is to use two separate 3/2-way valves. Fundamentally, such a scheme does not differ from the option described in the previous paragraph with a 5/3-way valve. The figure on the right shows in sequence, from left to right, a 3/2-way valve, a flow regulator with a built-in check valve, an air motor, another flow regulator with a built-in check valve, and another 3/2-way valve.

Noise suppression

The noise generated by an air motor during operation is composed of mechanical noise from moving parts and the noise generated by the pulsation of compressed air exiting the motor. The influence of noise from the air motor can have a rather noticeable effect on the general noise background at the installation site - if, for example, compressed air is allowed to freely escape from the air motor into the atmosphere, then the sound pressure level can reach, depending on the specific unit, up to 100-110 dB (A ) and even more.

First, you need to try, if possible, to avoid creating the effect of mechanical resonance of sound. But even in the best conditions, the noise can still be very noticeable and uncomfortable. To eliminate noise, silencers should be used - simple devices specially designed for this purpose and dispersing a compressed air flow in their housing and filter material.

According to the material of construction, mufflers are classified into those made of sintered (that is, powdered and then molded / sintered at high pressure and temperature) bronze, copper or of stainless steel, sintered plastics, as well as those made of woven wire enclosed in a steel or aluminum mesh housing, and made on the basis of other filter materials. The first two types are usually small bandwidth, and in size, and inexpensive. Such mufflers are usually placed on or near the air motor itself. An example of them can serve, among others,.

Wire mesh mufflers can have a very large capacity (even orders of magnitude greater than the compressed air demand of the largest air motor), a large connection diameter (from our offer, up to a 2" thread). Wire mufflers, as a rule, become dirty much more slowly, can be effectively and repeatedly regenerated - but, unfortunately, they usually cost much more than sintered bronze or plastic ones.

As for the placement of silencers, there are two main options. by the most in a simple way is to screw the muffler directly onto the air motor (if necessary, through an adapter). However, firstly, the compressed air at the air motor outlet is usually subject to rather strong pulsations, which both reduce the effectiveness of the muffler and, potentially, reduce its service life. Secondly, the muffler does not remove the noise at all, but only reduces it - and when the muffler is placed on the unit, there will most likely be quite a lot of noise anyway. Therefore, if possible and if desired, in order to reduce the sound pressure level as much as possible, the following measures should be taken, selectively or in combination: 1) install some kind of expansion chamber between the air motor and the silencer, which reduces the pulsation of compressed air, 2) connect the silencer through a soft flexible hose , which serves the same purpose, and 3) move the muffler to a place where the noise will not disturb anyone.

It should also be remembered that the initially insufficient capacity of the muffler (due to an error in selection) or its (partial) blockage from contamination that occurred during operation can lead to a significant resistance exerted by the muffler to the flow of outgoing compressed air - which, in turn, leads to to reduce the power of the air motor. Choose (including consulting with us) a muffler with sufficient capacity and then, during its operation, monitor its condition!