RU2659119C2 - Pressure regulator for fuel plants in internal combustion engines, particularly for automotive field - Google Patents

Abstract

FIELD: control; regulation.

SUBSTANCE: disclosed is pressure regulator (10) for fuel gas plants in internal combustion engines, particularly for the automotive field, the device being placed between a tank of the gas at high pressure and line (4) for sending the gas to the engine. Device comprises at least first stage (1) for gas pressure reduction, having gas inlet (1a) and outlet (1b) openings, wherein inlet opening (1a) is in fluid communication with the gas tank, the pressure of the gas is regulated by said at least first stage (2) to an intermediate first value and at least second stage (2) for gas pressure regulation, located downstream of first stage (1), comprising regulating resilient membrane (15). Membrane separates first and second chamber (16, 17) of second stage (2), the regulated gas being supplied with the first intermediate pressure into first chamber (16) and the gas being delivered from first chamber (16) through outlet opening (2b) at the preselected pressure for sending to the engine. Device further comprises a secondary circuit associated with pressure regulation second stage (2), comprising auxiliary duct (21) designed to connect second chamber (17) of second stage (2) with line (4) for sending gas to the engine, a valve unit comprising valve seat (22) with respective shutter member (23) and electromagnetic actuator (24). Actuator (24) being controlled by electronic control unit (30) which, according to the required pressure value at the outlet from device (10) controls the opening of shutter member (23) in order to regulate the gas pressure in first chamber (16) of second stage (2), so as to keep the pressure value at the outlet of the device stable.

EFFECT: invention can be used in internal combustion engines (ICE) fuel injection systems.

13 cl, 2 dwg

Description

FIELD OF TECHNOLOGY

The present invention relates to a device for regulating pressure for gas fuel (e.g. methane) installations in internal combustion engines, and, in particular, for the automotive field of technology having the characteristic features described in the limiting part of the main claim 1.

BACKGROUND

It is a known possibility to install in vehicles vehicles made with the additional possibility of supplying gas to their engines, thereby providing a substantially mixed supply or only supply of fuel gas. Installations of this type are usually formed by a high-pressure gas tank, a pressure reducer / regulator providing a suitable gas pressure for supplying the engine, and several channels and associated devices to ensure that the tank is refueling and to ensure optimal operation of the entire installation.

One skilled in the art will recognize that a pressure regulator is a key component of a plant for fuel gas engines. The pressure regulator must provide the supply of fuel gas in the required volume and under the required pressure. In particular, it must keep the pressure at the outlet unchanged:

- in response to gradual changes in pressure in the inlet pressure and sudden changes;

- during the life of the regulator itself;

- in response to changes in gas flow required by the engine;

- in response to gradual and sudden changes in the ambient temperature or the temperature of the heating circuit of the pressure regulator / pressure reducer.

The pressure regulator should also provide sensitivity and the ability to quickly respond to engine requirements. The sensitivity and accuracy of the pressure regulator are extremely important for the correct operation of the fuel supply system of the engine with fuel injection, since it is necessary to ensure the exact dosage of the fuel supply to the engine.

Known pressure regulators containing an elastic membrane with a single-stage, two-stage or three-stage pressure reduction. These controllers contain a first stage containing a first chamber in communication with the fuel tank by means of a first valve, a part of the inner surface of the first chamber is formed by a first elastic membrane. Similarly to the first stage, subsequent stages also contain a chamber, a part of the inner surface of which is formed by an elastic membrane.

Regulators of this design can not always guarantee a stable outlet pressure for some time; The main reasons for this are that:

- the elastic membrane is exposed to temperature changes, and temperature increases lead to lower pressure at the outlet;

- changes in inlet pressure affect the outlet pressure, especially in the case of a single-stage pressure reducer;

- pressure regulation is subject to fluctuations in the gas flow rate required by the engine, especially if high flow rates are required;

- the membrane is subject to wear over time, which leads to the loss of its strength and elasticity characteristics, which initially provide the correct pressure regulation.

Another drawback of conventional regulators containing elastic membranes is their lower strength and reliability when used in the latest generation of fuel injection systems, which usually produce excessively high pressures, impulses and interruptions that a conventional regulator containing a membrane cannot quickly compensate.

In the past, various solutions have been used to eliminate the previously mentioned pressure stabilization problems under various operating conditions.

Pressure changes due to temperature changes, in particular, were eliminated by correcting the injection time by controlling the electronic control unit, or by reducing the range of temperature changes by using a thermostat, or by using various control technologies, for example piston technology, in which the membrane function is replaced by a movable piston made of metal material.

Changes in outlet pressure as a result of changes in inlet pressure were partially eliminated by dividing the pressure reduction into several stages; the presence of more steps provides a higher level of independence of the inlet pressure value, however, it should be understood that this leads to a corresponding increase in the size, connections and cost of the regulator. Alternatively, this problem has been eliminated by an appropriate compensation system to prevent any change in outlet pressure in the event of a change in inlet pressure.

The decrease in outlet pressure compared to the required pressure due to membrane wear has been eliminated by replacing the membrane. The extreme hydrodynamic conditions to which the membrane is exposed limit the life and characteristics over time, which leads to the need to replace it after a specified number of kilometers of the vehicle and / or to the need to manually recalibrate the set pressure, while each of the processes incurs additional costs for system user. As an alternative, piston regulators have been developed that do not require replacement parts.

These piston pressure regulators, as indicated earlier, have eliminated some of the common problems of conventional membrane regulators, but they have lower performance in other aspects. In particular, increased reaction time to engine requirements, worse dynamic response and higher sudden vibrations not absorbed by the membrane. The economic aspect is also important, since the piston regulator is more expensive and requires more complex production technologies.

Other specified solutions require a lot of data, and the electronic processing of these signals essentially increases the complexity of the software and equipment of the power system. The known actuators used are subject to high pressure changes and, therefore, are inevitably more difficult to manufacture, which affects the cost of the device.

In conclusion, in recent years, electronic pressure regulators have been developed, characterized by the possibility of changing the pressure supplied to the injection devices, depending on the set data, such as engine parameters, to expand the range of fuel consumption and increase the stability of the outlet pressure. The main disadvantage of these regulators is that they require a large amount of data and a control algorithm to ensure that they are processed and the correct signal is supplied to the regulator to ensure that the outlet pressure matches the required pressure. In addition, in this case, complex software and equipment are required, which leads to an increase in cost, installation time and number of problems. The controller has more required parameters for operation and, therefore, more possible causes of failure in its operation.

SUMMARY OF THE INVENTION

The objective of the present invention is to provide a device for regulating pressure, made with the possibility of eliminating the above problems using the advantages of membrane technology and simplicity in terms of components and installation of conventional regulators, while also providing low cost.

In particular, the objectives of the present invention are to:

- ensuring a stable outlet pressure in response to changes in the temperature of the external environment;

- ensuring a stable outlet pressure in response to changes in inlet pressure;

- providing a stable outlet pressure in response to changes in the required flow;

- ensuring stable outlet pressure over the life of the regulator;

- maintaining membrane technology and, therefore, the benefits it provides, avoiding costly maintenance operations;

- creating an economical device, made with the possibility of quick installation;

- creating a device that is easy to use and does not require obtaining numerous data for its operation, therefore, reducing the number of possible causes of failure in its operation.

These problems are solved by means of a pressure control device implemented in accordance with the attached claims.

According to one aspect of the present invention, there is provided a pressure regulating device for gas fuel plants in internal combustion engines located between a high pressure gas tank and a gas supply line to an engine, comprising: at least a first stage for decreasing gas pressure having a corresponding inlet and a gas outlet, wherein the inlet is in fluid communication with the gas tank, the gas pressure is adjusted by at least a first stage and has an intermediate value between the gas pressure to the specified device and for the specified device; at least a second stage for regulating gas pressure, comprising a regulating elastic membrane located at least at the first stage, the membrane separating the first and second chamber of at least the second stage from each other, the regulated gas is supplied under intermediate pressure to the first chamber, and gas comes from the first chamber at a predetermined pressure for supplying to the engine, while at least the second stage has corresponding inlet and outlet openings for gas, and the outlet from at least the second stage is in fluid communication with a line for supplying gas to the engine, the device comprising a secondary circuit connected to the specified device and connected in parallel with at least a second stage for regulating pressure, comprising: an auxiliary channel for connecting to the message the fluid of the second chamber of at least the second stage with a line for supplying gas to the engine; a valve assembly located on the auxiliary channel and comprising a valve seat with a corresponding valve member and an electromagnetic actuator operably coupled to the valve member to control the latter relative to the valve seat; a drive controlled by an electronic control unit, which is configured to control the opening of the shutter element in accordance with the pressure value at the outlet of the device for controlling the gas pressure in the first chamber of at least the second stage so as to maintain a stable pressure value at the output of the device; however, the device also contains elastic means associated with the shutter element for pushing it to close the valve seat in opposition to the force of the electromagnet actuator, and the electromagnet is provided to open the valve seat.

According to one embodiment, in the device, at least the first lowering step is represented by a type comprising an elastic membrane.

According to another embodiment, in the device, at least the first lowering stage is represented by a piston type.

According to another embodiment, a channel is made in the device for communicating between the first and second camera of at least the second regulation stage.

According to another embodiment, in the device the channel is made in a membrane separating the first and second chamber of at least the second stage.

According to another embodiment, in the device, the width of the channel cross section is smaller than the minimum flow cross section made in the secondary circuit.

According to another embodiment, in the device, the control unit comprises actuator controls for changing the pressure at the outlet of the device by a predetermined number of required values, i.e. according to a given function or curve.

According to another embodiment, in the device, the control unit comprises drive control means in functional dependence on one or more of the following parameters: outlet gas pressure; engine rotation speed; opening time of gas injection devices contained in the engine; combustion air flow rate; required engine torque.

According to yet another embodiment, the drive is controlled in the device by an alternating electric current controlled by an electronic control device.

According to another embodiment, in the device, the control membrane is operatively connected to the valve element configured to interact with a valve seat formed on the outlet from the second stage, so as to regulate the pressure by acting on the valve element from the intermediate value at the inlet of the second steps to the pressure value at the outlet of the specified device.

According to another embodiment, in the device at the inlet of the first lowering stage, the valve seat is equipped with a corresponding shutter element, made with the possibility of sliding movement towards and away from the saddle.

According to another embodiment, in the device, the shutter member is operatively connected to an elastic pressure-regulating membrane located in a corresponding seat formed in the housing of the first lowering stage.

According to another embodiment, the device comprises a pressure sensor configured to measure pressure behind said device and transmit a pressure data signal to the control unit.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described in more detail in the following description of a preferred embodiment of the invention, given by way of non-limiting example with reference to the accompanying drawings, in which:

in FIG. 1 shows a general connection diagram of a pressure control device according to the present invention;

in FIG. 2 is an enlarged partial cross-sectional view of part of the diagram of FIG. one.

BEST MODE FOR CARRYING OUT THE INVENTION

With reference to the accompanying drawings, a pressure control device for motor vehicles containing a fuel gas engine implemented in accordance with the invention is indicated by a pointer 10 throughout the description. The device is designed to be located between a gas tank (e.g. methane) under high pressure and an engine that are not shown.

The device comprises a first pressure reduction stage 1 in fluid communication through line 3 with a tank containing pressurized fuel gas; in the gas tank is under pressure Pin.

The inlet and outlet openings in the first stage 1 are indicated by indicators 1a and Inappropriate.

Further, in the processing chain behind the first stage 1, the device comprises a second pressure control stage 2 containing the corresponding inlet and outlet openings 2a, 2b.

The inlet 2a is in fluid communication with the outlet 1b of the first lowering step, and the outlet 2b is in fluid communication with the user device, i.e. with line 4 feed.

The two control stages 1, 2 can be located in one housing or, alternatively, in two separate device housings.

At the inlet 1a of the first lowering stage 1, the valve seat 5 is equipped with a corresponding valve 6, made with the possibility of sliding movement towards and away from the saddle. This shutter can be made, for example, sliding along the main axis of the first stage 1 of regulation or parallel to it. The shutter element 6 is functionally connected to an elastic pressure-regulating membrane 7 located in the corresponding seat (shown schematically and indicated by a pointer 1c) in the housing of the first lowering stage 1.

In an embodiment of the invention, the control membrane 7 may also be arranged to move along or parallel to the main axis of the first control stage 1. In a preferred embodiment of the invention, the shutter element 6 and the control membrane 7, in particular, are made coaxially to each other. In an embodiment of the invention, the shutter member 6 and the control membrane 7 are mechanically connected by means of a connecting pin or rod 8. In accordance with the above design, the movement of the elastic membrane 7 towards the shutter element 6 leads to the movement of the shutter element 6 from the corresponding seat 5 and, thus to the opening of the inlet 1a.

The control membrane 7 divides the volume of the inner cavity of the first stage 1 into the front chamber 11 and the rear chamber 12, wherein the inlet and outlet openings 1a, 1b are formed in the front chamber.

The counter spring 13, designed to push the membrane 7 towards the shutter element 6, is located in the rear chamber 12. The counter spring 13 is calibrated depending on the required pressure at the outlet of the first stage (for example, 4 bar in the preferred embodiment of the invention).

The front chamber 11 also performs the function of a “compensation chamber”, since in this chamber gas acts on the membrane 7 in such a way as to ensure equilibrium between the latter and the counter spring 13 under the required gas pressure at the outlet (indicated by the pointer Pout). This front chamber 11 is in communication through a gas outlet 1b with a gas outlet 14 for gas from the first stage 1. The gas pressure at the outlet of the first stage 1 is a regulated gas pressure P1 in the chamber 11, for example 4 bar.

The rear chamber 12 is separated from the front chamber 11 by means of an elastic membrane 7, which also provides a seal between the two chambers 11, 12. The rear chamber 12 may be in fluid communication with the atmosphere, as a result of which the air contained therein will be at atmospheric pressure, or it may be in fluid communication with an engine intake manifold (not shown), and as a result, the air contained therein will be below said intake manifold.

Similarly to the first stage 1, the second regulation stage 2 is also formed in the housing 2c (shown only schematically), the volume of the internal cavity of which is divided by an elastic membrane 15, which defines the first (front) chamber 16 and the second (rear) chamber 17. Inlet and outlet openings 2a 2b are formed in the first chamber 16.

The inlet 2a of the second stage 2 of the regulation is in direct fluid communication with the outlet 1b of the first stage 1 and with the chamber 16 of the second stage 2 without blocking elements located between them.

The control membrane 15 is operatively connected to the shutter element 18, designed to block the outlet 2b of the second regulation stage 2. The saddle 19, made with the possibility of interaction with the shutter 18, is made on the outlet 2b, the shutter is made with the possibility of sliding movement towards and away from the saddle. This shutter element 18 can be made, for example, sliding along the main axis of the second regulation stage 2 or parallel to it.

The control membrane 15 can be arranged to move along the main axis of the housing of the second control stage 2 or parallel to it and is connected to the shutter element 18 so that by moving it towards the shutter element to push the latter to its seat 19 and, therefore, close the outlet channel 2b.

A counter spring 20 is located in the second chamber 17, which allows the membrane 15 to be pushed to the front position, i.e. towards the gate member 18. This counter spring 13, calibrated against the pressure difference required to open the valve seat 19, is connected to the membrane 15.

The first front chamber 17 also performs the function of a “compensation chamber”, since in this chamber gas acts on the membrane 15 in such a way as to ensure equilibrium between the last and the counter spring 13 and the pressure in the second chamber, indicated by pointer P3, under the required outlet gas pressure indicated by the pointer Pout.

In accordance with the main characteristic feature of the invention, the device 10 comprises a secondary circuit (contributing to the main circuit of the control steps) connected in parallel to the second control step 2, in accordance with the following more detailed description.

The secondary circuit, in particular, contains an auxiliary channel 21 for connecting with the fluid communication of the rear second chamber 17 of the second stage 2 with a line 4 for supplying gas to the engine, and a valve assembly located on the channel 21. The valve assembly includes a valve seat 22 with a corresponding the shutter 23 and the electromagnetic actuator 24 associated with the shutter to control the latter relative to the valve seat 22.

With reference to FIG. 2, the electromagnetic actuator 24 is designed to provide communication between the inlet channel 25 and the rear second chamber 17 through the channel portion 21, and the exhaust channel 26 to communicate with the channel of the line 4 for supplying gas to the engine injection units (not shown) through another auxiliary channel section 21 .

The inlet channel 25 is in communication with the camera 27 located behind the shutter element 23 of the electromagnetic actuator. The shutter is connected to the seat 22 to act on it and close it. The bolt element 23 is also associated with a counter spring 28, configured to perpendicularly push the bolt element into position, when it is in position, the saddle closes. This configuration forms an electrovalve connected to the shutter element 23 in such a way that, if the electromagnet (electromagnetic actuator) is not magnetized, the counter spring 28 will maintain the shutter element 23 in the closed position, thereby preventing fluid from escaping from the second chamber 17.

The valve seat 22 is configured to open by powering an electromagnet. This leads to the displacement of the shutter element 23 and, therefore, the opening of the seat 22. When the seat 22 is in the open position, it is possible for liquid to pass into the channel 4.

In accordance with the invention, the drive 24 is controlled by an electronic control unit 30, which, depending on the pressure value at the outlet of the device, controls the opening of the shutter element 23 to control the gas pressure in the second chamber 17 of the second stage 2 so as to maintain a stable value pressure at the outlet of the device.

The control unit is designed to supply a drive control signal to the solenoid valve 22-24, the signal is generated by analyzing or comparing the value of the valve Pout, measured further in the technological chain of the device, for example, by means of a pressure sensor located in the injection unit and the required output pressure value (preferred value is, for example, 2 bar). The pressure sensor is configured to measure pressure and provide a signal with data on the measured pressure to the control unit.

The second chamber 17 of the second stage 2 is also in fluid communication with the corresponding first chamber 16 through the through hole 31 (passing, for example, through the membrane 15). The width of the cross section of the hole 31 is less than the width of the minimum passage section of the secondary circuit to ensure the correct operation of the system in accordance with the following more detailed description.

When the device 10 is inoperative and / or if the gas flow rate is zero, the valve seat 5 of the inlet channel 1a is closed while the membrane 7 is held in equilibrium by the pressure P1 in the chamber 11, which in this case is the predetermined set pressure of the first stage 1 ( constituting, for example, 4 bar). In this case, since the chamber 11 is connected to the chamber 16 connected to the chamber 17, which, in turn, is connected to the chamber 27, the pressure in these chambers is the same, i.e. P1. Closing the valve seat 19 is provided by the force of the counter spring 20 on the membrane 15, which, in turn, is mechanically attached to the valve element 18. Holding the valve seat 22 in the closed position is provided by pushing the valve element 23 in the forward position (relative to the seat) by the counter spring 28, wherein the electrovalve 22-24 is non-magnetized.

Therefore, when the system is started, magnetization of the electrovalve 22-24 is ensured and, thus, it is possible to open the shutter member 23 of the actuator 24, opening the channel allows gas to escape from the chamber 17 for use, and, therefore, decreases the gas pressure P3 in the chamber 17. As indicated previously, the portion of the channel opening 31 between the two chambers 16, 17 is smaller than the minimum portion of the channel in the secondary circuit, as a result of which the pressure differential between chambers 16, 17, with a higher pressure in the latter, and the differential makes it possible to open the seat 19 with gas coming from the second stage 2. In practice, this pressure moves the membrane 15 towards the retracted position until it reaches equilibrium with the force of the spring 20 and the pressure in ( back) of the second chamber 17, properly adjusted to generate the required outlet pressure. In this equilibrium state, the membrane 15 is in an intermediate position; as a result, the bolt element 18 is also moved towards the retracted position relative to its seat 19, opening the seat.

The gas passes through channel 4 under an adjusted pressure P2 (2 bar) to the injection unit.

Similarly, during the operation of the system, the balance between the forces acting on the membrane 15 provides the required outlet pressure P2. In particular, the force exerted on the rear side of the membrane 15 (i.e., on the surface of the membrane facing the chamber 17) is formed by the pressure P3, as well as the spring 20. This pressure P3 is controlled by the actuator 24, which, in turn, is controlled , carried out by the control unit depending on the pressure signal Pout; changes in this pressure P3 provide the ability to hold the desired pressure value at the outlet.

This kinematic configuration of the movable elements makes it possible to determine the correct relative positions between the gate element 18 and the associated sealing valve seat 19, providing the constant gas flow pressure required to power the engine in the range of operating modes.

For example, a pressure drop Pout to a value of 1.5 bar relative to a desired value of 2 bar is read by an electronic control unit that controls the actuator 24 by extending the opening of the shutter member 23 to lower the pressure P3, which will lead to a greater opening of the channel through the seat 19 to increase the pressure Pout and maintain its desired value of 2 bar. Pressure control and compensation are therefore carried out directly based on the pressure signal Pout; i.e. when changing, i.e. increasing or decreasing the pressure Pout for any of the above reasons (membrane wear, temperature increase, etc.) provides its immediate compensation, ensuring optimal stability of the control system in any operating conditions.

In particular, if the value of the gas pressure in the outlet channel is lower than a predetermined value, after the pressure drop in the second chamber 17, the membrane pushes the second stage of the elastic means 20 and, therefore, opens the channel 18 by the shutter member at the outlet 2b.

It should also be noted that the pressure drop between P2 and P3 during operation is very low, that is, the gas flow between the chamber 17 and line 4 is very low. The function of the secondary circuit and actuator 24 is not to provide a certain flow rate, as in the case of known electronic devices for regulating pressure, but to change the pressure P3, providing the possibility of forming a circuit and actuator 24 of small size and simpler design, which therefore have more low cost and higher level of reliability.

It should also be noted the advantage, which lies in the design of the device, eliminating the need for an inlet solenoid valve located in the high pressure channel, since its function is performed by the solenoid valve 22-24 of the actuator, i.e. when it is in the closed state, the pressures acting on it ensure the retention of both gate elements 6 and 18 in the closed position.

Therefore, the device is configured to stably hold the required gas pressure of, for example, 2 bar. In a further embodiment of the invention, the electronic control unit, in addition to the pressure signal Pout, processes other technical data, such as one or more of the following parameters: engine speed, opening time of the gas injection devices contained in the engine, combustion air flow rate, required engine torque. Depending on this data, the actuator 24 can be controlled to change the pressure Pout to another desired value of, for example, 3 bar, and to hold it stably.

This second desired value may have a pressure value P1 adjusted by the first stage as the maximum value.

It should also be noted that the control unit 30 can be advantageously equipped with means for controlling the actuator 24 to change the pressure at the outlet of the device 10 by a predetermined number of required values, i.e. according to a given function or curve.

Moreover, in a further embodiment of the invention, the drive 24 is controlled by an alternating electric current controlled by an electronic control device. In this case, the pressure at the outlet of the device may, for example, be proportional to the average current value.

Thus, the invention solved the tasks and provided the previously indicated advantages compared with the known solutions.

Claims (25)

1. Device (10) for regulating the pressure for gas fuel systems in internal combustion engines, located between the gas tank under high pressure and the line (4) for supplying gas to the engine, containing: at least a first stage (1) for lowering the gas pressure, having respective gas inlet (1a) and gas outlet (1b), wherein the inlet (1a) is in fluid communication with the gas tank, the gas pressure is adjusted by at least the first stage (1) and has an intermediate value between the gas pressure to the specified device and the specified device, at least a second stage (2) for regulating the gas pressure, comprising a regulating elastic membrane (15) located behind at least the first stage (1), the membrane separating the first and second chamber (16, 17) of at least the second stage (2) from each other, the regulated gas is supplied under intermediate pressure to the first chamber (16), and the gas flows from the first chamber (16) under a predetermined pressure for supplying to the engine, wherein at least the second stage (2) has corresponding gas inlet (2a) and outlet (2b) openings, and the outlet (2b) from at least the second stage (2) is in fluid communication with line (4) ) to supply gas to the engine, characterized in that it contains a secondary circuit connected to the specified device, connected in parallel with at least a second stage (2) for regulating the pressure and containing: - an auxiliary channel (21) for connecting with the fluid communication of the second chamber (17) at least the second stage (2) with a line (4) for supplying gas to the engine, - a valve assembly located on the auxiliary channel (21) and comprising a valve seat (22) with a corresponding valve member (23) and an electromagnetic actuator (24) operably coupled to the valve member (23) for controlling the latter relative to the valve seat (22), - a drive (24) controlled by an electronic control unit (30), which is configured to control the opening of the shutter element (23) in accordance with the pressure value at the outlet of the device (10) for regulating the gas pressure in the first chamber (16) according to at least a second stage (2) so as to maintain a stable pressure value at the outlet of the device; however, the device (10) also contains elastic means (28) associated with the shutter element (23) for pushing it to close the valve seat (22) in opposition to the force of the actuator magnet (24), and the electromagnet is provided to open the valve seat (22) . 2. The device according to claim 1, wherein at least the first lowering step (1) is represented by a type comprising an elastic membrane. 3. The device according to claim 1, wherein at least the first lowering step (1) is represented by a piston type. 4. The device according to p. 1, in which for communication between the first and second camera (16, 17) at least the second stage (2) of regulation made channel (31). 5. The device according to claim 4, in which the channel (31) is made in a membrane (15) separating the first and second chamber (16, 17) of at least the second stage (2). 6. The device according to claim 4, in which the width of the cross section of the channel (31) is less than the minimum flow cross section made in the secondary circuit. 7. The device according to one of the preceding paragraphs, in which the control unit (30) comprises drive control means (24) for changing the pressure at the outlet of the device (10) by a predetermined number of required values, i.e. according to a given function or curve. 8. The device according to any one of paragraphs. 1-6, in which the control unit (30) comprises means for controlling the drive (24) depending on one or more of the following parameters: - gas pressure at the outlet, - engine rotation speed, - the opening time of the gas injection devices contained in the engine, - combustion air flow, - required engine torque. 9. The device according to any one of paragraphs. 1-6, in which the drive (24) is controlled by an alternating electric current controlled by an electronic control device. 10. The device according to any one of paragraphs. 1-6, in which the control membrane (15) is functionally connected to the shutter element (18), configured to interact with the valve seat (19) formed on the outlet (2b) from the second stage, so as to regulate the pressure through exposure membrane (15) to the shutter element (18) from the intermediate value at the inlet of the second stage to the pressure value at the outlet of the specified device. 11. The device according to any one of paragraphs. 1-6, in which at the inlet (1a) of the first lowering stage, the valve seat (5) is equipped with a corresponding shutter element (6) made with the possibility of sliding movement towards and away from the saddle. 12. The device according to claim 11, in which the shutter element (6) is functionally connected to the elastic pressure-regulating membrane (7) located in the corresponding seat formed in the housing of the first lower stage (1). 13. The device according to any one of paragraphs. 1-6, 12, containing a pressure sensor configured to measure pressure (Pout) behind the specified device and transmit a signal with pressure data (Pout) to the control unit (30).

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