EP3146167A2

EP3146167A2 - Compressed-air engine with an integrated active chamber and with active intake distribution

Info

Publication number: EP3146167A2
Application number: EP15726034.0A
Authority: EP
Inventors: Guy Negre; Cyril Negre
Original assignee: MDI Motor Development International SA
Current assignee: MDI Motor Development International SA
Priority date: 2014-05-22
Filing date: 2015-05-18
Publication date: 2017-03-29
Anticipated expiration: 2035-05-18
Also published as: ES2715515T3; FR3021347A1; NZ725405A; US20170211435A1; RU2016145407A3; KR20170007306A; ZA201608834B; AU2015263264B2; IL248944A0; AU2015263264A1; AP2016009621A0; WO2015177076A3; RU2701784C2; RU2016145407A; CA2946481A1; CA2946481C; US10371023B2; WO2015177076A2; EP3146167B1; IL248944B

Abstract

The invention proposes an active chamber engine, comprising at least one piston (2) slidingly mounted in a cylinder (1) and operating according to a three-phase thermodynamic cycle comprising an isobaric and isothermal transfer, a polytropic expansion with work and an exhaust at ambient pressure, which is preferably supplied with compressed air contained in a high-pressure storage tank (12), in which the volume of the cylinder (1) swept by the piston is divided into an active chamber (CA) and an expansion chamber (CD), and in which the compressed air is used to move the intake valve (9) in order to open and then close the intake duct, making it possible to supply the active chamber of the engine, the compressed air having been used for said actions then being reused in the engine to produce additional work.

Description

"Active chamber compressed air motor included

and active distribution at admission »

TECHNICAL FIELD OF THE INVENTION

The invention relates to an engine operating in particular with compressed air, or any other gas, and using a chamber called "active chamber"

The invention relates to the distribution on admission of such an engine and more particularly for a motor comprising an active chamber included, and in particular for a multi-modal self-expanding motor with active chamber included.

STATE OF THE ART

The term "distribution" is the set of means used to supply such a motor with compressed gas.

The inventors have filed numerous patents concerning engines and their installations, using gases and more particularly compressed air for a completely clean operation in urban and suburban sites:

They have in particular filed an international patent application WO-A1-0 03/036088 to the content of which we will be able to refer, concerning a motor-compressor unit - motor-alternator with additional compressed air injection operating in mono-energy and multiple -énergies.

In these types of engines operating with compressed air and having a compressed air storage tank, it is necessary to relax the compressed air stored at very high pressure in the tank - but whose pressure decreases as and when as the tank empties - at a stable intermediate pressure called final pressure of use, in a buffer capacity - said working capacity - before its use in the engine cylinder or cylinders of the engine.

To solve the problems of the expander, the inventors have also filed a patent application WO-A1-0 03/089764, the contents of which we will be able to refer to, concerning a dynamic variable-rate expander and a distribution for motors powered with injection of compressed air, comprising a high-pressure compressed air tank and a working capacity.

In the operation of these "load-relieving" motors, the filling of the expansion chamber always represents a relaxation without work which is detrimental to the overall efficiency of the machine.

To solve the problem indicated above, the inventors then filed a patent application WO-A1-2005 / 049968 describing a compressed air motor powered preferentially by compressed air, or by any other compressed gas, contained in a high-pressure storage tank, previously expanded to a nominal working pressure in a so-called working capacity buffer.

In this type of engine according to the teachings of WO-A1-2004 / 049968:

the expansion chamber is constituted by a variable volume equipped with means making it possible to produce a work, it is twinned and in contact by a permanent passage with the space included above the main engine piston which is equipped with a piston stop device at top dead center,

during stopping of the stroke of the engine piston at its top dead center, the air or the gas under pressure is admitted into the expansion chamber when it is at its smallest volume and, under the thrust, increase its volume by producing a job,

the expansion chamber being kept substantially at its maximum volume, the compressed air contained therein then expands in the engine cylinder, thus pushing the engine piston in its downward stroke, thereby providing work,

- During the recovery of the engine piston during the exhaust time, the variable volume of the expansion chamber is reduced to its smallest volume to start a complete work cycle.

The engine expansion chamber according to this invention actively participates in the work. The engine is thus called "active chamber" engine.

The document WO-A1-2005 / 049968 teaches in particular a thermodynamic cycle in four phases during its operation in mono-energy mode with compressed air characterized by:

- an isothermal relaxation without work; - a transfer - slight relaxation with work said quasi-isothermal;

- polytropic relaxation with work;

an exhaust at ambient pressure.

Document WO-A1-2008/028881, which presents a variant of the teachings of document WO-A1-2005 / 049968, teaches the same thermodynamic cycle, but using a conventional crank-crank device, the engine expansion chamber according to the invention actively participating in the work.

The engines according to the teachings of documents WO-A1-2005 / 049968 and WO-A1-2008/028881 are known as "active-chamber motors".

Subsequently, the inventors filed a patent application for an enclosed active chamber air or compressed-gas engine which uses the same thermodynamic cycle as the motors according to the teachings of WO-A1-2005 / 049968 and A1 -2008/028881, as well as a conventional crank-crank device.

According to the teachings of document WO-A1 -2012 / 045693, the inventors have proposed an enclosed active-chamber motor comprising at least one piston slidably mounted in a cylinder and driving a crankshaft by means of a conventional and working crank-rod device. according to a four-phase thermodynamic cycle comprising:

- an isothermal relaxation without work;

- a transfer - slight relaxation with work said quasi-isothermal; - polytropic relaxation with work;

an exhaust at ambient pressure.

Fueled preferably by compressed air, or any other compressed gas, contained in a high-pressure storage tank, through a so-called working capacity buffer which is fed with compressed air, or any other compressed gas, contained in a high-pressure storage tank, which is expanded to an average pressure known as working pressure in a working capacity, preferably through a dynamic expansion device, in which:

the active chamber is included / incorporated in the engine cylinder;

the engine cylinder comprises at least one piston slidably mounted in at least one cylinder whose volume swept by the piston is divided into two distinct parts, a first portion constituting the active chamber CA and a second portion constituting the expansion chamber CD;

- The cylinder is closed at its upper part by a cylinder head having at least one duct and an intake port, and at least one duct and an exhaust port and which is arranged so that when the piston is at its top dead center, the residual volume between the piston and the cylinder head is, by construction, if not nonexistent, reduced to the minimum clearances allowing operation without contact between the piston and the cylinder head;

compressed air or gas under pressure is admitted into the cylinder above the piston when the volume of the active chamber CA is at its smallest volume and which, under the continuous thrust of the compressed air at constant pressure of work, will increase its volume by producing a work representing the quasi-isothermal transfer phase;

the admission of the compressed air, or pressurized gas, into the cylinder is closed when the maximum volume of the active chamber CA is reached, and the quantity of compressed air or gas under pressure, included in said active chamber then relaxes by pushing the piston on the second part of its stroke which determines the expansion chamber CD producing a job thus ensuring the relaxation phase;

- The piston has reached its bottom dead point, the exhaust port is then open to ensure the exhaust phase during the ascent of the piston over its entire race.

The volume of the active chamber CA included and the volume of the expansion chamber CD are dimensioned such that at the nominal operating pressure of the engine, the pressure at the end of expansion at low dead point is close to the ambient pressure, especially atmospheric. The volume of the active chamber is determined by the closing of the admission.

Advantageously, and especially in monoenergy operation with compressed air, the active chamber motor included described above comprises a plurality of successive cylinders of increasing displacements.

Preferably, the engine is powered like the teachings of documents WO-A1-2005 / 049968 and WO-A1 -2008/028881, by compressed air, or by any other compressed gas, contained in a high pressure storage tank, previously expanded, at a nominal working pressure, in a buffer capacity - said capacity of job.

However, even if it is possible in the case of a multi-stage engine to feed the first of the cylinders at high pressures, it remains necessary to relax the compressed air at very high pressure contained in the high-pressure storage tank. up to a nominal working pressure and this expansion operation, either leads to a loss of efficiency by the use of a conventional expansion valve or, with the use of the teachings of WO-A1-0 03/089764, does not cost energy, but this relaxation does not allow to perform any work of relaxation between the high pressure contained in the tank and the nominal working pressure in the capacity of work at constant volume.

The inventors then filed a new patent application WO-A1-2012 / 045694 to the content of which reference may be made which claims an active chamber compressed air motor included in which:

- The storage tank of compressed air at high pressure, or any other pressurized gas, directly feeds the intake of the engine cylinder;

the filling of the active chamber CA is effected at a constant intake pressure at each engine revolution, this intake pressure being degressive as the pressure in the storage tank decreases as and when measurement of the progressive emptying of this tank;

the volume of the active chamber CA included is variable and is gradually increased as the pressure in the storage tank which determines said intake pressure decreases;

the means for opening and closing the admission of compressed air into the active chamber CA not only make it possible to open the orifice and the intake duct substantially at the top dead center of the piston stroke, but they also make it possible to modify the duration and / or the angular sector of the admission, as well as the passage section of the opening; the volume of the active chamber CA included is dimensioned for the maximum storage pressure, then it is gradually increased so that, depending on the inlet pressure, the volume ratio between the active chamber CA included and the chamber relaxation CD, the pressure at the end of relaxation before the opening of the exhaust is close to atmospheric pressure.

The engine according to WO-A1 -2012 / 045694 also acts as an expander, the invention thus making it possible to provide an engine called "autodetendeur" which, for the supply of the active chamber CA, does not require any expansion valve independent of any one type.

The multi-modal autodetender motor with active chamber included according to the teachings of document WO-A1-2012 / 045694 notably implements, during its operation in single-energy compressed air mode, a three-phase thermodynamic cycle comprising:

- an isobaric and isothermal transfer phase

- a polytropic relaxation phase with work

an exhaust phase at ambient pressure.

In the operation of this engine, the volume, variable depending on the pressure of the high pressure storage tank, the active chamber included determines the amount of compressed air injected. The higher the inlet pressure, the smaller the volume of the active chamber must be.

In order to obtain a correct operation in all phases of use of the engine, it is therefore necessary to feed it with great precision according to the various parameters including speed or rotational speed, the supply pressure, the load determined by the position of the accelerator, the temperature.

For this purpose, it is necessary to be able to vary:

- the moment of opening of the intake according to the rotational speed of the engine before or after top dead center in order to take into account the inertia of the gases, but also the ratio between the times of establishment of the pressure,

the closing moment of the intake, as a function of the rotational speed of the engine, but also of the intake pressure,

- the lifting of the intake valve according to the desired load. The difficulty lies in the realization of the opening and closing means of the admission of compressed air into the active chamber included which not only allow to open the orifice and the intake duct substantially at the top dead center of the stroke of the piston, but which also make it possible to modify the duration and / or the angular sector of the admission, as well as the passage section of the opening.

The distribution of engines of all types is generally provided by valves whose operation is well known. A valve closes the intake and / or exhaust duct and has a valve head held by springs resting on a circular valve seat formed around an orifice communicating the intake duct and / or or exhaust with the combustion chamber and / or expansion contained in the cylinder.

The valve head opens the circuit by penetrating the chamber to be powered by mechanical mechanical cams and pushers acting on the tail or stem of the valve which extends the valve head.

In other areas of motorization and for other technical reasons, particularly with regard to the reduction of pollution and in order to control the intake and exhaust of conventional combustion engines, a large number of engine manufacturers work on systems enabling to control the phasing and duration of valve openings during operation and have filed numerous patents for these applications. Complex mechanical systems driven by electric stepper motors have also been developed and marketed, in particular by BMW (Registered Trademark) with the device called "Vamos".

The inventors have also filed patent application WO-A1-

03/089764 to the content of which we can refer to a distribution by progressive control valve.

Many works have been undertaken concerning electromechanical devices, in particular controlled by electromagnets easily controllable to take into account the various operating parameters, but the electrical powers to be implemented to allow accelerations and speed of operation. displacement of the valves demand, given the weight and the inertia of the latter, considerable powers.

The invention, particularly adapted to active chamber compressed air motors, including multi-modal self-expanding motors with active chamber included, proposes to solve all the problems mentioned above while providing additional power.

The active intake distribution device according to the invention applied to the compressed air motors uses the compressed air contained in the high-pressure storage tank and / or in the intake circuit to move the intake valve in order to opening and closing the intake duct for supplying the active chamber of the engine, the compressed air used for these actions is then reused in the engine to produce additional work.

BRIEF SUMMARY OF THE INVENTION

The invention proposes an active chamber motor operating according to a three-phase thermodynamic cycle comprising:

an isobaric and isothermal transfer phase;

- a polytropic relaxation phase with work;

an exhaust phase at ambient pressure;

this engine comprising:

at least one cylinder fed with a gas under pressure, preferably with compressed air, contained in a high-pressure storage tank,

at least one piston which is slidably mounted in this cylinder,

a crankshaft driven by the piston by means of a conventional crank-rod device,

a cylinder head which closes at its upper part the volume of the cylinder, which is swept by the piston, and which comprises at least one intake duct in which flows a flow of gas under pressure to fill the cylinder, an orifice of admitting the pressurized gas above the piston, and at least one exhaust port and an exhaust duct, the cylinder head being arranged such that when the piston is at its top dead center, the residual volume included between the piston and the cylinder head is, by construction, reduced to only minimum allowing operation without contact between the piston and the cylinder head,

At least one intake valve which cooperates sealingly with a valve seat formed in the cylinder head and which delimits the inlet orifice,

engine in which:

The volume of the cylinder swept by the piston is divided into two distinct parts of which a first portion constituting an active chamber which is included in the cylinder and a second part constituting an expansion chamber,

Under the continuous thrust of the pressurized gas admitted into the cylinder, at constant working pressure, the volume of the active chamber increases by producing a work representing the isobaric and isothermal transfer phase,

The admission of the pressurized gas into the cylinder is closed as soon as the maximum volume of the active chamber is reached, the quantity of gas under pressure included in said active chamber then relaxing while pushing the piston on the second part of its stroke which determines the relaxation chamber by producing a work thus ensuring the polytropic relaxation phase,

- the piston has reached its bottom dead point, the exhaust port is then open to ensure the exhaust phase during the ascent of the piston over its entire path to its top dead center,

- the engine torque and speed are controlled by the opening and closing of the intake valve allowing the intake valve to be opened substantially at the top dead center of the piston stroke, and allowing, by closing the valve, changing the duration and / or the angular sector of the intake, and the passage section of the intake opening to, depending on the pressure of the compressed gas contained in the storage tank and the pressure at the end of the expansion phase, to determine the quantity of pressurized gas admitted as well as the volume of the active chamber, characterized in that:

- a) the intake valve is mounted movably in axial displacement between a low closing position in which it is in sealing engagement on its valve seat, and a high opening position, - b) in the direction of its opening, the intake valve moves axially, in the opposite direction to that of the flow of the pressurized gas flow filling the cylinder,

- c) in its closed position, the inlet valve is kept autoclave closed on its valve seat by the pressure prevailing in the intake duct and applying to the intake valve,

- d) the engine comprises means for controlling the opening of the intake valve, substantially at the top dead point of the piston stroke, to cause the detachment of the intake valve of its seat to allow the establishment the inlet pressure in the active chamber, the valve then traversing its full opening stroke under the action of the differential pressure forces exerted by the gas under pressure on the corresponding parts of the intake valve,

e) the engine comprises a pneumatic cylinder for closing the intake valve which comprises a cylinder of cylinder and a closing piston which is connected in axial displacement with the intake valve, and which is slidably mounted in the cylinder of cylinder inside which it delimits in a sealed manner a cylinder control chamber, called closure chamber,

- f) the engine comprises at least one intake valve opening control channel which connects said closure chamber to a source of pressurized gas which is either the upper part of the active chamber of the cylinder or the conduit; intake, ie the pressurized gas tank,

- g) the motor comprises an active distribution channel which connects said closure chamber to the upper part of the active chamber and a valve closing the flow of gas in the active distribution channel, called active distribution valve, whose the opening is controlled to bring the closure chamber into communication with the upper part of the active chamber, to close the inlet valve and to produce work which is added to the work of the pre-admitted pressure gas charge, via the intake duct, in the active chamber.

According to other features of the invention:

- the active dispensing valve is controlled according to the following cycle: i) opening of the active dispensing valve to put the closure chamber in communication with the active chamber to cause the closing of the inlet valve and, during the expansion phase, allow the expansion of the compressed gas, contained in the closure chamber, in the expansion chamber of the cylinder producing a work which is added to the work of the pre-admitted pressure gas charge, via the intake duct, in the active chamber,

ii) at the end of the expansion phase, closing again of the active dispensing valve to maintain inside the closure chamber the pressure of the expanded gas whose value is close to that of the atmospheric pressure;

said means d) for controlling the opening of the intake valve comprise:

d1) an intake valve opening control channel which connects the upper part of the active chamber to the inlet duct or the pressurized gas tank,

- d2) and a controlled shutter valve of the flow of gas in the opening control channel, said opening valve;

- said opening control valve is controlled according to the following cycle:

k1) at the end of the exhaust phase, when the piston is substantially at the top dead center of its travel, opening of said valve, to allow to establish in the active chamber a pressure identical to that prevailing in the intake duct and induce the detachment of the intake valve from its seat,

(k2) the intake valve then traverses its full opening stroke under the action of the differential pressure forces exerted by the gas under pressure on the corresponding parts of the intake valve,

k3) closing said valve as soon as the inlet valve opens;

the engine comprises a channel which connects said closure chamber to the inlet duct and / or the pressurized gas tank, and a shut-off valve for the circulation of the gas in this channel, the opening and closing of which are controlled , to cause the closing of the intake valve, prior to the placing the closure chamber in communication with the volume of the cylinder swept by the cylinder.

said means for controlling the opening of the intake valve comprise a finger formed in relief on the upper face of the piston which, during the end of stroke of the piston towards its top dead point, acts through the intake port, on a portion facing the intake valve to take off its seat.

- the active dispensing valve is controlled according to the following cycle:

j) opening of the active dispensing valve to put the closure chamber in communication with the active chamber to put the closure chamber in communication with the expansion chamber of the cylinder, to allow expansion of the compressed gas, contained in the chamber of closing in the expansion chamber of the cylinder producing a work which is added to the work of the pressurized gas charge previously admitted into the active chamber,

jj) at the end of the expansion phase, closing again the active dispensing valve to maintain inside the closure chamber a pressure whose value is close to that of the atmospheric pressure;

- The maximum open position of the intake valve is defined by an adjustable stop whose axial position, in the direction of movement of the intake valve, is controlled to vary the flow rate of pressurized gas admitted into the cylinder via the intake duct.

BRIEF DESCRIPTION OF THE FIGURES

Other objects, advantages and features of the invention will appear on reading the description, without limitation, of several embodiments, with reference to the appended drawings in which:

- Figure 1A schematically shows an engine according to the invention, active chamber included in the cylinder, which is illustrated in axial section at its bottom dead point, and its compressed air supply device;

FIGS. 1B to 1D are views similar to that of FIG. 1A on which the motor is illustrated in different phases successive operation of the engine according to the invention and in which Figure 1B represents the engine being admitted, the intake valve having been opened from top dead center;

- Figure 2 is a view similar to that of Figure 1D which illustrates a second embodiment of an engine according to the invention;

FIG. 3 is a view similar to that of FIG. 1B which illustrates a third embodiment of an engine according to the invention;

- Figure 4 is a view similar to that of Figure 1D which illustrates a fourth embodiment of an engine according to the invention.

DETAILED DESCRIPTION OF THE FIGURES

Description of Figures 1a to 1d. FIG. 1A represents an active chamber self-expansion motor equipped with an active intake distribution assembly according to the invention.

FIGS. 1A to 1D show an active chamber engine CA operating according to a three-phase thermodynamic cycle comprising:

- isobaric and isothermal transfer;

- polytropic relaxation with work;

an exhaust at ambient pressure.

The engine comprises at least one cylinder 1, only one of which is represented, which is fed with a gas under pressure, preferably with compressed air, contained in a high-pressure storage tank 12.

The engine comprises a piston 2 which is slidably mounted in the cylinder 1, and a crankshaft 5 which is driven by the piston 2 by means of a conventional crank-rod device 3, 4.

The volume of the engine cylinder 1 which is swept by the piston 2 is divided along an imaginary line DD '(corresponding to a division plane orthogonal to the axis of the cylinder) into two parts: a first part constituting the active chamber CA, which is thus included in the cylinder 1, and a second part constituting the expansion chamber CD.

The engine further comprises a cylinder head 6 which closes at its upper part the volume of the cylinder 1, which is swept by the piston 2. The cylinder head 6 comprises at least one intake duct 8 which is connected to the tank 12 and in which flows the flow of pressurized cylinder filling gas, an inlet 7 of the gas under pressure above the piston 2.

The cylinder head further comprises at least one exhaust port and one exhaust duct (not shown).

The cylinder head 6 is arranged such that, when the piston 2 is at its top dead point, the residual volume between the piston 2 and the cylinder head 6 is, by construction, reduced to the minimum clearances allowing the operation without contact between the piston 2 and the cylinder head 6.

The cylinder head 6 comprises at least one intake valve 9, one of which is illustrated, which cooperates sealingly with a valve seat 20 formed in the cylinder head 6 and which delimits the inlet orifice 7.

In known manner, in such an engine:

the volume of the cylinder 1 swept by the piston 2 is divided into two distinct parts of which a first part constituting a so-called active chamber CA which is included in the cylinder 1, and a second part constituting a relaxation chamber CD,

under the continuous thrust of the pressurized gas admitted into the cylinder 1, at constant working pressure, the volume of the active chamber CA increases by producing a work representing the quasi-isothermal transfer phase,

the admission of the pressurized gas into the cylinder 1 is closed as soon as the chosen maximum volume of the active chamber CA is reached, the quantity of pressurized gas included in the active chamber CA then relaxing while pushing the piston 2 onto the second part of his race which determines the CD relaxation chamber by producing a work thus ensuring the relaxation phase,

- The piston 2 having reached its bottom dead point, the exhaust port is then open to ensure the exhaust phase during the ascent of the piston 2 over its entire race to its top dead center,

the torque and the engine speed are controlled by controlling the opening and closing of the intake valve 9 by making it possible to open the intake valve 9, substantially at the top dead center of the piston stroke (vertically according to the orientation of the figure), and allowing, by closing the valve 9, to change the duration and / or the angular sector of the intake, and the passage section of the intake opening to, depending on the pressure the gas contained in the storage tank 12 and the pressure at the end of the expansion phase, to determine the amount of pressurized gas admitted and the volume of the active chamber CA.

The intake duct 8 is directly connected to the high pressure reservoir 12 which directly supplies the active chamber CA and is at the same pressure as that of the reservoir.

The pressure in the intake duct 8 is identical to that of the storage tank 12, for example of the order of 100 bars, and is greater than that prevailing in the active chamber CA and the expansion chamber CD, for example equal to 1.5 bar at the moment of the cycle corresponding to the bottom dead center of the piston, at the end of expansion, just before the opening of the exhaust valve.

According to the invention, the intake valve 9 is mounted to move axially between a low position (considering the general vertical orientation of the figures and without reference to earth gravity) closing - shown in Figure 1A - in which it is in sealing engagement on its valve seat 20, and a high opening position - shown in Figure 1B.

In the direction of its opening, the inlet valve 9 moves axially - upwards, in the opposite direction to that of the flow of the gas flow F under pressure of filling the cylinder. Thus, the inlet valve opens in the opposite direction to the flow of air under pressure filling the engine cylinder.

In its closed position, the inlet valve 9 is held closed autoclave on its valve seat 20 by the pressure in the intake duct 8 and applied to the intake valve, that is, ie on the valve head inside the intake duct 8.

The engine comprises means for controlling the opening of the intake valve 9, substantially at the top dead center of the piston stroke, to cause the detachment of the intake valve 9 from its seat 20 and to establish in the chamber activates a pressure to that prevailing in the intake duct 8.

During its opening phase, the valve then traverses its full opening stroke under the action of the differential forces of pressure exerted by the gas under pressure on the corresponding parts of the intake valve and in particular on the head of the valve, that is to say on the one hand on the lower surface 22 in the form of disc subjected to pressure prevailing in the cylinder 1, and secondly on the upper surface 24 subjected to the pressure in the intake duct 8, the difference between the areas of these two surfaces corresponding substantially to the area of the section of the rod or tail 26 of the valve 9.

In its closed position, the inlet valve 9 is held in its seat 20, autoclaved by the pressure of the compressed air contained in the intake circuit, and / or in the air storage tank 12 compressed, the pressure in the active chamber CA and the engine expansion chamber CD being lower during the relaxation and exhaust phases of operation.

The engine comprises a pneumatic cylinder V closing the intake valve 9 which, by way of non-limiting example, is here arranged in the cylinder head 6.

The jack V comprises a cylinder of cylinder 100 and a closing piston 102 which is connected in axial displacement with the rod 26 of the intake valve 9, and which is slidably mounted in the cylinder cylinder 100 inside which it delimits sealingly an upper chamber 104 of the cylinder, called the closing chamber of the valve 9.

The motor comprises an active distribution channel X1 which connects the closing chamber 104 to the upper part of the active chamber CA arranged included in the cylinder 1.

The maximum maximum opening position of the inlet valve 9 is defined by an adjustable stop 30 which extends into the chamber 104 and whose axial position, in the axial direction of displacement of the valve, is controlled (by means of means not shown in the figures) to vary the flow of pressurized gas admitted into the cylinder via the intake duct. The controlled adjustable stop thus acts as a "throttle" controlled by an accelerator. The displacements of the abutment are for example controlled and caused by means of an electric motor step by step.

The adjustable stop 30 makes it possible to stop the upward and automatic upward movement of the intake valve 9 by modifying its lift as a function of the required motor operating parameters. The engine comprises a controlled valve Y closing the flow of gas in the channel X1 active distribution, called Y valve active distribution, whose opening can be controlled to put the chamber 104, closing the intake, in communication with the upper part of the active chamber CA by establishing in the closure chamber 104 a complementary pressure on the upper face of the piston 102 by pushing, by the action of this piston, the intake valve 9 on its seat 20 and thus closing the intake circuit thereby ending the work of the active chamber CA.

The active dispensing valve Y is then kept open during the expansion time by allowing the compressed gas contained in the closure chamber 104 to relax together with the gas contained in the expansion chamber, while producing a work which is added in the work of the pressure gas charge previously admitted, via the intake duct, into the active chamber.

The engine comprises an X2 channel for controlling the opening of the intake valve 9 which connects the upper part of the active chamber CA to the intake duct 8.

The engine comprises a valve Z controlled shutter of the flow of gas in the channel X2, called valve opening of the intake valve, whose opening can be controlled to put the upper part of the active chamber CA in communication with the intake duct 8.

When the piston 2 of the engine is close to its top dead point (FIG. 1B), by opening the opening valve Z, the intake circuit is, at the chosen moment, put into communication with the active chamber CA of the cylinder in allowing the establishment of a pressure identical to that contained in the intake circuit and, because of the difference in areas mentioned above, the pressure, automatically pushes the intake valve 9 upwards and the valve d admission, in its movement, opens the intake circuit.

For example, for a valve with a diameter of 20 mm controlled by a 6 mm valve stem, the bottom surface is 3.14 cm2 and the top surface is 2.86 cm2 (3.14 - 0 , 28), a thrust of 28 kg is exerted to open automatically the inlet valve 9 and allow the filling of the active chamber CA.

The closing of the intake valve 9 is then ensured by placing the active chamber CA in communication with the closure chamber 104 thus creating a complementary pressure on the upper surface of the piston 102 of the closing cylinder V, which then pushes the valve intake 9 on its seat 20 and closes / closes the admission to allow the relaxation cycle of the active chamber CA in the relaxation room CD ..

From the beginning of the expansion (Figure 1C) the volume of the closure chamber 104 is maintained in communication with the expansion chamber CD of the engine and the compressed air contained in the closure chamber 104 is expanded in the expansion chamber CD of the engine by producing a work which is added to the work of relaxation of the load admitted into the active chamber.

Thus, within the meaning of the invention, the valve Y is an active dispensing valve, and the channel X1 is an active distribution channel.

At the end of relaxation, the communication between the active chamber and the expansion chamber of the cylinder and the closure chamber 104 is again sealed by maintaining in the latter a pressure close to atmospheric pressure, allowing the renewal of the cycle.

The operation of the so-called active distribution according to the invention is therefore understood in which, advantageously, the energy necessary for the opening and closing of the inlet valve 9 is provided by the pressure prevailing in the storage tank and or the intake circuit for opening, and prevailing in the active chamber for closure, then is reused by producing additional work in the cylinder.

The volume of the closing chamber 104 is of reduced value, for example, without limitation, less than 10% of the cylinder capacity of the cylinder 1.

The same applies to the channels connecting the inlet and the active chamber, and the closure chamber 104 to the expansion chamber CD, the passage sections of which are calculated to allow a flow rate sufficient for establishing the pressures in the chambers. different rooms. These various channels have reduced diameters for example of the order of 0.5 to 2 millimeters for a diameter of the main intake duct of the order of 20 millimeters.

Preferably, Y and Z valves of the electromechanical type, constituted in particular in the form of solenoid valves adapted and easily controllable by an electronic management unit (not shown), will be used.

In addition the control by electronic management and pneumatic control allows opening and closing speeds of the valve (s) and angular control phases of high precision.

In the operating cycle of the active distribution described above, the expansion of the volume of air contained in the closure chamber is carried out in conjunction with that of the active chamber and with pressure drops of about from the nominal pressure to the pressure. exhaust.

Description of Figure 2 The following description is made by comparison with the embodiment previously described with reference to Figures 1A to 1 D.

The previous design is completed by an additional channel X3 which connects the intake duct 8 to the closing chamber 104 of the jack V.

The engine also comprises a valve T controlled closing the flow of gas, compressed air, in the channel X3, whose opening can be controlled to put the intake duct 8 and / or the tank 12 in communication with the closing chamber 104.

Thus, the closure chamber 104 has at least two ducts, X3 and X1 each provided with controlled closure means, T and Y, for closing the closure chamber 104, successively in communication with the one hand with the intake circuit and / or the high-pressure storage tank 12, and secondly with the active and expansion chamber of the cylinder.

Closing of the intake valve 9 is ensured by placing in communication the intake circuit and / or the reservoir of storage with the closure chamber 104, via the channel X3, and by controlling the opening of the valve T, thereby creating a complementary pressure on the surface of the closing piston 102 which pushes the inlet valve 9 on its seat 20 and closes the inlet to allow the relaxation cycle of the active chamber CA in the expansion chamber CD.

Thus, the active expansion of the closure chamber 104 can be delayed to intervene later in the cycle, by controlling the opening of the valve Y.

From the beginning of the relaxation, or during relaxation, the volume of the closure chamber 104 is in communication with the expansion chamber CD and the compressed air contained in the closure chamber 104 relaxes in the expansion chamber CD by producing a work that is added to the work of relaxation of the load admitted into the active chamber CA.

Substantially at the end of expansion, the communication between the active and expansion chamber of the engine and the closure chamber 104 is again sealed by maintaining in the latter a pressure close to atmospheric pressure allowing renewal of the cycle.

Description of Figure 3

The following description is made by comparison with the first embodiment illustrated in Figures 1A-1D.

According to this embodiment, there are provided mechanical means for causing the release of the intake valve 9 of its seat 20, which act directly on the head of the intake valve 9.

In the case of an engine having to operate at substantially constant speeds of rotation, and which therefore does not require variations in the timing of the opening of the intake, the opening of the intake valve 9 is advantageously simplified by the integration of such a mechanical device.

For this purpose, said means for controlling the opening of the intake valve 9 are constituted by a finger D, or pusher, which is formed in relief on the upper face of the piston (2) and which extends vertically upwards facing the head opposite the intake valve 9.

By its arrangement and its dimensioning, the opening control finger D is able to cooperate mechanically with the lower face 20 of the head of the intake valve 9 to push the latter vertically upwards.

It is during the end of stroke of the piston towards its top dead center, that the finger D acts, through the inlet orifice, on the portion facing the lower face 22 of the head of the piston. intake valve 9 to lift it off its seat.

The finger D is positioned in line with the lower part of the intake valve head so that it slightly raises the intake valve creating a leak which puts the intake circuit in communication with the active chamber. CA by establishing in the closure chamber 104 a complementary pressure on the upper surface of the piston 102 and, by the action of the piston 102 connected to the tail of the valve, by pushing the intake valve 9 on its seat 20 by closing thus the intake circuit by putting an end to the work of the active chamber CA.

The valve then travels its full opening stroke under the action of the differential pressure forces exerted by the gas under pressure on the corresponding parts of the intake valve 9.

After opening of the inlet valve, and beginning of the expansion cycle, because of the descent of the piston 2, the finger D no longer acts on the intake valve 9, and the rest of the cycle is identical to that described with reference to Figures 1A to 1D, implementing the valve Y.

Description of Figure 4

The description which follows is made by comparison with the second embodiment illustrated in FIG. 2.

The arrangement of the channel X2 and the associated valve Z for controlling the opening of the intake valve is modified.

The jack V is a double-acting jack with two sealed chambers separated by the piston 102. The lower chamber 105 is a chamber for controlling the opening of the intake valve 9 which, via the channel X2, is connected to the intake duct 8 and / or to the tank 12 of gas under pressure.

Thus, the closure chamber 104 has at least two ducts, X3 and X1, each provided with controlled shutter means T, Y for putting the closure chamber 104 in succession in communication with the circuit on the one hand. inlet and / or the high-pressure storage tank 12, and secondly with the active and expansion chamber of the cylinder.

The opening of the intake valve 9 is controlled by the valve Z which supplies pressurized gas to the lower chamber 105 of the cylinder V which is an opening chamber.

Closing of the inlet valve 9 is ensured by placing the intake circuit and / or the storage tank in communication with the closure chamber 104, via the channel X3 and by controlling the opening of the valve T , thus creating a complementary pressure on the surface of the closing piston 102 which pushes the intake valve 9 on its seat 20 and closes the inlet to allow the expansion cycle of the active chamber CA in the expansion chamber CD .

The closure is obtained because of the area of the piston 102 subjected to the pressure, which is greater on the side of the chamber 104, than on the opening chamber 105 side (the difference corresponding substantially to the area of the section of the rod of the intake valve).

Thus, the active relaxation of the closure chamber can be delayed to intervene later in the cycle, by controlling the opening of the valve Y.

From the beginning of the relaxation, or during relaxation, the volume of the closure chamber 104 is then placed in communication with the expansion chamber CD and the compressed air contained in the closure chamber 104 expands in the chamber relaxation by producing a job that is added to the work of relaxation of the load admitted into the active room.

Substantially at the end of relaxation, the communication between the active and the expansion chamber of the engine and the closing chamber 104 is closed again, while maintaining in the latter a pressure close to the atmospheric pressure allowing the renewal of the cycle.

According to this design, the piston 102 of the jack V successively controls the opening and closing of the intake valve 9.

According to a variant, not shown, it is possible, as for the chamber 104, to connect the chamber 105 to the active chamber through a channel X1 'and a valve Y', thus achieving two parallel active distribution circuits.

The volumes of the closing chamber 104 and of the opening chamber 105 can then be placed in communication with the expansion chamber and the compressed air contained therein is expanded in the expansion chamber, making it possible to increase the work. releasing the load admitted by relaxing in the main engine cylinder.

Due to the flexibility of use and the almost unlimited adjustment possibilities, the engine equipped with the "active" intake distribution according to the invention can be used on all land, sea, rail and aeronautical vehicles. The active chamber motor according to the invention can also and advantageously find its application in the emergency generator sets, as well as in many domestic cogeneration applications producing electricity, heating and air conditioning.

The active chamber motor according to the invention has been described with operation with compressed air. However, it can use any compressed gas / gas at high pressure, without departing from the scope of the claimed invention.

The invention is not limited to the embodiments described and shown: the materials, the control means, the devices described may vary within the limit of equivalents, to produce the same results. The number of engine cylinders, their displacements, the maximum volume of the active chamber relative to the displaced volume of the cylinder (s) and the number of stages of relaxation, may vary.

Claims

An active chamber engine operating on a three phase thermodynamic cycle comprising:

an isobaric and isothermal transfer phase;

- a polytropic relaxation phase with work;

an exhaust phase at ambient pressure;

this engine comprising:

at least one cylinder (1) supplied with a gas under pressure, preferably with compressed air, contained in a high-pressure storage tank (12),

- at least one piston (2) which is slidably mounted in this cylinder (1),

a crankshaft (5) driven by the piston by means of a conventional crank-rod device (3,4),

- a cylinder head (6) which closes at its upper part the volume of the cylinder (1), which is swept by the piston (2), and which comprises at least one intake duct (8) in which flows a flow of gas under pressure to fill the cylinder, an inlet (7) for the gas under pressure above the piston, and at least one exhaust port and an exhaust pipe, the cylinder head being arranged in such a way that when the piston (2) is at its top dead center, the residual volume between the piston (2) and the cylinder head (6) is, by construction, reduced to the minimum clearances allowing operation without contact between the piston (2 ) and the cylinder head (6),

at least one intake valve (9) which cooperates sealingly with a valve seat (20) formed in the cylinder head (6) and which delimits the inlet orifice (7),

engine in which:

- The volume of the cylinder (1) swept by the piston (2) is divided into two distinct parts, a first part constituting an active chamber (CA) which is included in the cylinder (1) and a second part constituting a relaxation chamber (CD),

under the continuous thrust of the pressurized gas admitted into the cylinder, at constant working pressure, the volume of the active chamber (CA) increases producing a work representing the isobaric and isothermal transfer phase,

the admission of the gas under pressure into the cylinder (1) is closed as soon as the maximum volume of the active chamber (CA) is reached, the amount of gas under pressure included in said active chamber (CA) then relaxing by pushing the piston (2) on the second part of its stroke which determines the expansion chamber (CD) by producing a job thus ensuring the phase polytropic relaxation,

- the piston (2) has reached its bottom dead point, the exhaust port is then open to ensure the exhaust phase (7) during the ascent of the piston over its entire stroke to its top dead center ,

- the engine torque and speed are controlled by the opening and closing of the intake valve (9) allowing the intake valve (9) to be opened substantially at the top dead center of the piston stroke , and allowing, by closing the valve (9), to modify the duration and / or the angular sector of the intake, as well as the passage section of the intake opening to, depending on the pressure compressed gas contained in the storage tank (12) and the pressure at the end of the expansion phase, to determine the quantity of pressurized gas admitted and the volume of the active chamber (CA),

characterized in that

- a) the inlet valve (9) is mounted movably in axial displacement between a low closing position in which it bears tightly on its valve seat (20), and a high opening position,

- b) in the direction of its opening, the inlet valve (9) moves axially, in the opposite direction to that of the flow of the pressurized gas stream filling the cylinder (1),

- c) in its closed position, the inlet valve (9) is kept autoclave closed on its valve seat by the pressure in the intake duct (8) and applied to the valve of admission,

- d) the engine comprises means for controlling the opening of the intake valve (9), substantially at the top dead point of the piston stroke, to cause the detachment of the intake valve (9) of its seat to allow the establishment of the intake pressure in the active chamber (CA), the valve then traversing its full opening stroke under the action of differential pressure forces exerted by the gas under pressure on the corresponding parts of the intake valve,

e) the engine comprises a pneumatic cylinder for closing the intake valve (9) which comprises a cylinder of cylinder (100) and a closing piston (102) which is connected in axial displacement with the intake valve, and which is slidably mounted in the cylinder cylinder (100) within which it (102) sealingly delimits a control chamber of the cylinder, said closure chamber (104),

- f) the engine comprises at least one inlet valve opening control channel (X2) (9) which connects said closure chamber (104) to a source of pressurized gas which is either the upper part of the the active chamber (CA) of the cylinder, either the inlet duct (8) or the pressurized gas tank,

- g) the engine comprises an active distribution channel (X1) which connects said closing chamber (104) to the upper part of the active chamber (CA) and a valve (Y) closing the flow of gas in the active distribution channel (X1), said valve (Y) of active distribution, the opening of which is controlled to put the closure chamber in communication with the upper part of the active chamber (CA), closing the inlet valve ( 8) and produce a work which is added to the work of the previously admitted pressurized gas charge, via the intake duct, in the active chamber.

2. Motor according to claim 1, characterized in that the valve (Y) active distribution is controlled according to the following cycle: i) opening of the active dispensing valve to put the closure chamber (104) in communication with the chamber active (CA) to cause the closing of the inlet valve (9) then, during the expansion phase, allow the expansion of the compressed gas, contained in the closure chamber, in the expansion chamber (CD) of the cylinder producing a work which is added to the work of the pre-admitted pressure gas charge, via the intake duct, in the active chamber;

ii) at the end of the expansion phase, closing again of the active dispensing valve (Y) to maintain inside the closure chamber (104) the pressure of the expanded gas whose value is close to that of the atmospheric pressure.

3. Engine according to claim 2, characterized in that said means (d) for controlling the opening of the intake valve (9) comprise:

d1) an opening valve opening control channel (X2) which connects the upper part of the active chamber (CA) to the intake pipe (8) or the pressurized gas tank (12),

- D2) and a valve (Z) controlled shutter of the flow of gas in the opening control channel (X2), said valve (Z) aperture.

4. Motor according to claim 3, characterized in that said valve (z) opening control is controlled according to the following cycle:

k1) at the end of the exhaust phase, when the piston (2) is substantially at the top dead center of its travel, opening of said valve (Z), to allow to establish in the active chamber (CA) a pressure identical to that prevailing in the intake duct (8) and cause the detachment of the intake valve (9) from its seat (20);

k2) the inlet valve (9) then runs its full opening stroke under the action of the differential pressure forces exerted by the gas under pressure on the corresponding parts of the intake valve (9);

k3) closing said valve (Z) as soon as the inlet valve (9) opens.

5. Motor according to claim 2, characterized in that it comprises a channel (X3) which connects said closing chamber (104) to the inlet duct and / or the tank (12) of pressurized gas, and a valve (T) closing the flow of gas in this channel (X3) whose opening and closing are controlled, to cause the closure of the inlet valve, prior to the communication of the closure chamber ( 104) with the volume of the cylinder (1) swept by the cylinder (2).

6. Engine according to claim 1, characterized in that said means (d) for controlling the opening of the intake valve (9) comprise a finger (D) formed in relief on the upper face of the piston (2) which, during the end of stroke of the piston (2) towards its top dead center, acts through the inlet orifice, on a portion opposite (22) of the intake valve (9) to take off its seat (20).

7. Motor according to claim 6, characterized in that the active distribution valve (Y) is controlled according to the following cycle: j) opening of the active dispensing valve (Y) to put the closure chamber (104) in communication with the active chamber (CA) to put the closure chamber (104) in communication with the expansion chamber (CD) of the cylinder, to allow the expansion of the compressed gas, contained in the closure chamber (104), in the chamber detent (CD) of the cylinder by producing a work which is added to the work of the pressure gas charge previously admitted into the active chamber;

jj) at the end of the expansion phase, closing again the valve (Y) active distribution to maintain inside the closure chamber a pressure whose value is close to that of atmospheric pressure.

8. Motor according to any one of the preceding claims, characterized in that the maximum open position of the intake valve (9) is defined by an adjustable stop (30) whose axial position, in the direction of displacement of the intake valve (9) is controlled to vary the flow of pressurized gas admitted into the cylinder (1) via the intake duct.