CN113677883A - Hinged supercharger - Google Patents

Abstract

The articulated supercharger (1) forms an intake pipe (3) whose end has a tight spherical joint (16) fixed by a constraint device (17), the supercharger (1) connecting a heat source (39) to an expansion cylinder (32) and comprising a supercharger inlet orifice (4), a supercharger outlet orifice (6) housing a valve seat (9) and an actuator orifice (8) housing an intake valve actuator (50) of a control valve (10) cooperating with the valve seat (9) to close the intake pipe (3).

Description

Hinged supercharger

The present invention relates to an articulated supercharger intended in particular to enhance the transmission-expansion-regeneration internal combustion engine according to patent WO2016/120560 in the possession of the applicant, derived from french patent published on 8/5 of 2016 under number FR 3032236.

More specifically, the articulated supercharger according to the invention can be advantageously combined with a double-acting expansion cylinder with adaptive support according to patent WO2017/046479, also held by the applicant.

Patent WO2017/046479 allows the rigid assembly consisting of cylinder bore, lower cylinder head and upper cylinder head in the transfer-expansion-regeneration internal combustion engine according to patent WO2016/120560 to expand freely under the effect of temperature with respect to the gearbox attached thereto, without affecting the normal functioning of the piston moving in said cylinder bore.

In addition to the patents WO2016/120560 and WO2017/046479, the hinged supercharger according to the present invention is of particular interest in combination with the invention consisting of a regenerative cooling system according to the patent WO 2018/154214. The system, which also enhances the transfer-expansion-regeneration internal combustion engine according to patent WO2016/120560, is particularly suitable for manufacturing rigid assemblies of cylinder barrel, lower cylinder head and upper cylinder head of said engine made of cast iron or stainless steel, since it is suitable for maintaining said assemblies at a maximum temperature of about seven hundred degrees celsius compatible with these materials.

The hinged supercharger according to the present invention is also advantageously combined with the subject matter of french patent application No. 1759206, 10/2/2017, held by the present applicant. The present application describes a hydraulic regenerative valve actuator advantageously applied to a transfer-expansion-regenerative internal combustion engine according to patent WO2016/120560, preferably in a version thereof enhanced by the subject matter of patent WO 2017/046479.

French patent application No. 1759206 describes in particular that the lower and upper expansion cylinder heads can each house an actuator cylinder, which is constrained by a lower cylinder body constraint plate in the case of the lower expansion cylinder head on the one hand and by an upper cylinder body constraint plate in the case of the upper expansion cylinder head on the other hand, via a plate abutment on the cylinder head which engages therewith, the plates tending to move closer to one another by means of a plate tie rod.

However, patent WO2017/046479 and french patent application No. 1759206 show that the intake pipes of a transfer-expansion-regeneration engine delivering hot gases are integrated in the lower and upper head of said engine, these intake pipes being advantageously made of cast iron or stainless steel maintained at a temperature of about seven hundred degrees celsius according to patent WO 2018/154214.

It should be noted that it would be advantageous to be able to reach higher temperatures when the intake pipe of a transfer-expansion-regeneration engine delivers high-temperature gases that must avoid cooling. Obviously, the temperature should be as close as possible to the temperature of the gas, i.e. for example one thousand three hundred degrees celsius. In fact, if the temperature of the duct is comparable to that of the gas transported therein, the gas cannot transfer heat to the duct. Minimizing heat transfer between the gas and the conduit is beneficial to the ultimate energy efficiency of the transfer-expansion-regeneration engine.

It should also be noted that patent WO2017/046479 does enable the rigid assembly of the transfer-expansion-regeneration engine, formed by the cylinder barrel, the lower cylinder head and the upper cylinder head, to expand freely with respect to the gearbox to which it is attached. However, said patent does not specify how the intake pipe of said engine is connected to its heat source, which may consist of a burner, for example. However, the distance between the respective intake pipes of the lower and upper cylinder heads of the engine is liable to vary significantly due to the expansion of the rigid assembly formed by the cylinder barrel, the lower cylinder head and the upper cylinder head.

Similarly, french patent application No. 1759206, which describes a hydraulic regenerative valve actuator, envisages an actuator cartridge mounted on the expansion cylinder assembly of a transfer-expansion-regeneration internal combustion engine, said cartridge comprising a valve box housed in a lower expansion cylinder head or in an upper expansion cylinder head. In this case, the valve adapted to open or close the inlet duct may be led directly or indirectly into said valve housing accommodating the valve seat, the latter and/or a part of the valve housing leading said valve being adapted to be cooled by a valve cooling circuit in which the heat transfer fluid circulates.

Thus, the valve box, which is kept at a low temperature, provides a heat exchange surface area for the gas circulating in the intake pipe, thereby making it reach a high temperature. This arrangement therefore facilitates the cooling of the gas and therefore adversely affects the ultimate energy efficiency of the transfer-expansion-regeneration machine.

Based on these observations and in order to correct the inherent disadvantages of the various inventions and inventive combinations described above, the hinged supercharger according to the present invention is adapted to:

● mechanically separates in a compact manner, along the three axes of a three-dimensional cartesian coordinate system, the intake tube of a transfer-expansion-regeneration engine, on the one hand, from the lower or upper cylinder head with which it is engaged, and, on the other hand, from the heat source, so that the rigid assembly of the engine formed by the cylinder barrel, the lower cylinder head and the upper cylinder head, on the one hand, and the heat source, on the other hand, can expand freely relative to each other without being impeded by the intake tube and without producing mechanical stress on the tube;

● the intake duct of a transfer-expansion-regeneration engine is made of a material compatible with high temperatures, optionally advantageously different from the material forming the cylinder barrel and the lower and upper head of the engine, this strategy contributing to minimizing the cooling of the hot gases circulating in the intake duct;

● receives, houses and thermally and tightly insulates an actuator cartridge similar to that described in french patent application No. 1759206, without the use of a valve box that readily cools the hot gases circulating within the intake duct;

● contain intake valves that operate at high temperatures, which helps to minimize cooling of the hot gases circulating within the intake tubes;

● keep the intake valve fully functioning and sealed regardless of the relative position of the actuator barrel controlling the valve with respect to the intake pipe, which varies as a function of the expansion of the valve with respect to the barrel and with respect to the intake pipe.

It will be appreciated that the articulated supercharger according to the present invention is primarily intended for use in a transfer-expansion-regeneration internal combustion engine according to patent WO2016/120560 in the possession of the applicant.

However, the supercharger may also be applied without limitation to any gas conduit at elevated temperature, the opening and closing of which is controlled by valves, and the conduit interconnect assembly being adapted to expand and move relative to each other.

The articulated supercharger according to the invention envisages for a transfer-expansion-regeneration internal combustion engine in which a double-acting expansion piston moves in an expansion cylinder forming, together with an upper expansion cylinder head and a lower expansion cylinder head, an expansion cylinder head assembly, said engine comprising a compressor compressing working gas before it is discharged into a regeneration heat exchanger, in which said gas is preheated, whereas on leaving said exchanger said gas is superheated by a heat source before it is introduced into the expansion cylinder via a burner outlet pipe, then an intake pipe and through an intake valve controlled by an intake valve actuator, in order to expand therein and produce work on a power take-off shaft, said gas being subsequently discharged from the expansion cylinder before being reintroduced into the regeneration heat exchanger in order to generate work by transferring part of its heat to the working gas preheated by entering said exchanger, thereby obtaining cooling therein, said supercharger comprising:

● form a hollow supercharger body of the intake air duct that contains a supercharger inlet port in communication with a heat source, a supercharger outlet port leading to an expansion cylinder via an upper or lower expansion cylinder head, and an actuator bore that houses an intake valve actuator;

● a frusto-spherical end on the burner side, disposed at the level of the supercharger inlet port, said end forming a close spherical joint link with a complementary frusto-spherical surface on the burner side disposed outside the burner outlet tube;

● a frusto-spherical end portion on the cylinder head side, provided at the level of the supercharger outlet aperture, said end portion forming a tight ball joint link with a complementary frusto-spherical surface on the cylinder head side provided outside the upper or lower expansion cylinder head;

●, a valve seat provided adjacent the outlet orifice of the supercharger, against which the inlet valve can bear to close the orifice;

● restraining means which on the one hand press the frusto-spherical end portion on the burner side against a complementary frusto-spherical surface on the burner side and on the other hand press the frusto-spherical end portion on the cylinder head side against a complementary frusto-spherical surface on the cylinder head side.

The hinged supercharger according to the present invention comprises a valve seat having a complementary frusto-spherical surface on the valve seat side which engages with a frusto-spherical bearing region provided on the valve side of the intake valve end, said surface and said bearing region forming a tight spherical joint link when in mutual contact.

The hinged supercharger according to the present invention comprises an intake valve comprising a valve stem that can translate along its longitudinal axis in or with an upper valve stem guiding ball joint housed in an intake valve actuator, said ball joint enabling said valve to orient itself according to a limited angle relative to said actuator.

The hinged supercharger according to the present invention comprises a valve stem translatable along its longitudinal axis in a position memory valve stem seal holder housed in an intake valve actuator, said seal holder being radially movable relative to said actuator and comprising a valve stem seal forming a seal between said seal holder and the valve stem, and said seal holder further comprising a seal holder seal forming a seal between said seal holder and the intake valve actuator.

The hinged supercharger according to the present invention includes a position memory stem seal carrier that is held against the intake valve actuator by a stem seal carrier spring.

The hinged supercharger according to the present invention comprises a supercharger body housing an intake valve actuator via a thermally decoupled spacer that creates tightness and centering with the supercharger body on the one hand and the intake valve actuator on the other hand.

The hinged supercharger according to the invention comprises a restraining means consisting of at least one actuator restraining plate which is held pressed against the inlet valve actuator by at least one plate tie rod and via at least one plate abutment, so that said actuator is in turn held pressed against the supercharger body via an actuator bearing surface contained in the actuator bore, and so that the frusto-spherical end on the burner side is held pressed against a complementary frusto-spherical surface on the burner side, and/or the frusto-spherical end on the cylinder head side is held against a complementary frusto-spherical surface on the cylinder head side.

The articulated supercharger according to the invention comprises a restraining device consisting of at least one supercharger restraining vise on the burner side, which presses directly or indirectly via at least one vise bearing surface against the supercharger body in the vicinity of and in the direction of the supercharger inlet opening.

The invention, its characteristics and the advantages it provides will be better understood by the following description, given by way of non-limiting example, with reference to the accompanying drawings:

fig. 1 is a schematic cross-sectional view of an articulated supercharger according to the invention for a transfer-expansion-regeneration internal combustion engine according to patent WO2016/120560 in the possession of the applicant, said supercharger housing a hydraulic regeneration valve actuator, wherein the valves are compatible with said supercharger by various arrangements envisaged for the articulated supercharger of the invention, the supercharger restraint vice mounted on the burner side being shown in the form of a restraining device.

Fig. 2 is a three-dimensional view of an articulated supercharger according to the invention for a transfer-expansion-regeneration internal combustion engine according to patent WO2016/120560 in the possession of the applicant, said supercharger housing a hydraulic regeneration valve actuator, wherein the valves are compatible with said supercharger by various arrangements envisaged for the articulated supercharger of the invention.

Fig. 3 is a three-dimensional overall view of a transfer-expansion-regeneration internal combustion engine according to patent WO2016/120560 in the possession of the applicant, comprising two expansion cylinder head assemblies, each housing two articulated superchargers according to the present invention.

Detailed Description

In fig. 1 to 3, the hinged supercharger 1, various details of its components, alternative embodiments thereof and accessories thereof are shown.

As shown in fig. 3, the articulated supercharger 1 is particularly useful in a transfer-expansion-regeneration internal combustion engine 30, wherein a double-acting expansion piston 31 moves in an expansion cylinder 32, which forms an expansion cylinder head assembly 35 with an upper expansion cylinder head 33 and a lower expansion cylinder head 34.

As can be seen in fig. 3, the transfer-expansion-regeneration internal combustion engine 30 comprises a compressor 36 which compresses a working gas 37 before discharging it into a regeneration heat exchanger 38, wherein said gas 37 is preheated, while on leaving said heat exchanger 38 said gas 37 is superheated by a heat source 39.

On leaving the heat source 39, the working gas 37 enters the expansion cylinder 32 via the burner outlet pipe 46, then through the inlet pipe 3 and through the inlet valve 10 controlled by the inlet valve actuator 50, to expand therein and produce work on the power take-off shaft 40.

The working gas 37 is then discharged from the expansion cylinder 32 before being reintroduced into the regenerative heat exchanger 38, so as to be cooled therein by transferring part of its heat to the working gas 37 entering said exchanger 38 for preheating.

As shown in fig. 1 to 3, the articulated supercharger 1 according to the invention has a hollow supercharger body 2, which can advantageously be made of a hard material that is resistant to high temperatures, such as silicon carbide.

The supercharger body 2 forms an intake pipe 3 of a transfer-expansion-regeneration internal combustion engine 30, and includes a supercharger inlet port 4 communicating with a heat source 39, a supercharger outlet port 6 leading to an expansion cylinder 32 via an upper expansion cylinder head 33 or a lower expansion cylinder head 34, and an actuator port 8 accommodating an intake valve actuator 50.

As shown in particular in fig. 1 and 2, the hinged supercharger 1 according to the invention also has a truncated spherical end 5 on the burner side, which is arranged at the level of the supercharger inlet orifice 4, said end 5 forming with the complementary truncated spherical surface 14 on the burner side, arranged outside the burner outlet pipe 46, a tight spherical joint link 16, which can be made of a hard material resistant to high temperatures, such as silicon carbide.

It should be noted that advantageously the frusto-spherical end portion 5 on the burner side or the complementary frusto-spherical surface 14 on the burner side may have a tapered rather than spherical shape, so as to favour the formation of a line of contact, rather than an area of contact, between said end portion 5 and said surface 14. It should be noted that in this case, the concave portion must have a tapered shape.

Fig. 1 and 2 also show that the articulated supercharger 1 according to the invention also has a frusto-spherical end portion 7 on the cylinder head side, which is provided at the level of the supercharger outlet aperture 6, said end portion 7 forming a tight spherical joint link 16 with a complementary frusto-spherical surface 15 on the cylinder head side, which is provided outside the upper expansion cylinder head 33 or the lower expansion cylinder head 34.

It should be noted that advantageously the frusto-spherical end portion 7 on the cylinder head side or the complementary frusto-spherical surface 15 on the cylinder head side may have a tapered rather than spherical shape, facilitating the formation of a line of contact rather than an area of contact between said end portion 7 and said surface 15. It should be noted that in this case, the concave portion must have a tapered shape.

The hinged supercharger 1 according to the invention also comprises a valve seat 9, which is visible in particular in fig. 1 and 2, said valve seat 9 being provided in the vicinity of the supercharger outlet orifice 6, while an inlet valve 10 can rest against said valve seat 9 to close said orifice 6, so as to prevent the working gas 37 from the heat source 39 from entering the expansion cylinder 32.

It should be noted that the inlet valve 10 may advantageously be made of a hard material resistant to high temperatures, such as silicon carbide.

Finally, as shown in fig. 1 to 3, the articulated supercharger 1 according to the invention comprises a constraint device 17 which presses the frusto-spherical end 5 on the burner side against the complementary frusto-spherical surface 14 on the burner side and presses the frusto-spherical end 7 on the cylinder head side against the complementary frusto-spherical surface 15 on the cylinder head side.

According to a particular embodiment of the hinged supercharger 1 according to the invention, the valve seat 9 may have a complementary frusto-spherical surface 18 on the valve seat side, which engages with a frusto-spherical bearing area 19 provided at the end of the intake valve 10 on the valve side.

In this case, the surface 18 and the bearing region 19 form a tight ball joint link 16 when they are in contact with one another, so that the intake valve 10 can be oriented according to a limited angle relative to the articulated supercharger 1, while in each case producing tightness with the valve seat 9 with which it engages.

It should be noted that the complementary frusto-spherical surface 18 on the valve seat side may advantageously be of a conical rather than spherical shape, facilitating the formation of a line of contact rather than a contact area between itself and the frusto-spherical bearing area 19 on the valve side.

As best shown in fig. 1 and 2, the intake valve 10 may comprise a valve stem 11 that may translate along its longitudinal axis in or with an upper valve stem guide ball joint 66 housed in the intake pipe actuator 50, said ball joint 66 enabling said valve 10 to orient itself according to a limited angle relative to said actuator 50.

According to this alternative embodiment, the valve stem 11 may be translated along its longitudinal axis in the position memory valve stem sealing bracket 67 shown in fig. 1 and 2. The seal holder 67 is housed in the inlet valve actuator 50 and is radially movable relative to the actuator 50.

The seal holder 67 may advantageously include a stem seal 74 that provides a seal between the seal holder 67 and the valve stem 11, and the seal holder 67 may further include a seal holder seal 75 that provides a seal between the seal holder 67 and the intake valve actuator 50.

As can be seen in fig. 1 and 2, the position memory stem seal retainer 67 may be held against the intake valve actuator 50 by a stem seal retainer spring 68, which may be comprised of a stack of resilient washers, a coil spring, or any other type of spring known to those skilled in the art.

It will be observed that the pressure load exerted by the spring 68 on the sealing carriage 67 tends to fix the latter by friction in position relative to the actuator 50 of the inlet valve, without preventing it from moving when the valve stem 11 exerts a radial load of sufficient strength on it.

With an alternative embodiment of the hinged supercharger 1 according to the invention, it is shown in fig. 1 to 3 that the supercharger body 2 can accommodate the intake valve actuator 50 via a thermally decoupled spacer 13 which is tight and centered on the one hand with respect to the supercharger body 2 and on the other hand with respect to the intake valve actuator 50.

Advantageously, the thermally decoupled spacer 13 is made of a material with low thermal conductivity, such as zirconia.

As can be observed in particular in fig. 1 and 2, the lower part of the thermally decoupled spacer 13 can form a thermal isolation mesh 20 which protects the intake valve actuator 50 from the heat emitted by the working gas 37, which circulates at high temperature in the intake duct 3 formed by the supercharger body 2.

It should be noted that the thermal protection of the intake valve actuator 50 formed by the thermal isolation mesh 20 may be added to or replace the actuator body cooling circuit 69 particularly visible in fig. 1 and 2, which may be included in the lower portion of the intake valve actuator 50.

In fig. 1 to 3, it is shown that the restraining means 17 may consist of at least one actuator restraining plate 41 which is held pressed against the inlet valve actuator 50 by at least one plate tie 43 and via at least one plate abutment 42.

Thus, the intake valve actuator 50 is held pressed against the supercharger body 2 by the actuator support surface 12 of the actuator bore 8, while the truncated spherical end portion 5 on the combustor side is held pressed against the complementary truncated spherical surface 14 on the combustor side and/or the truncated spherical end portion 7 on the head side is held pressed against the complementary truncated spherical surface 15 on the head side.

As shown in fig. 1-3, it will be observed that the plate abutment 42 may be fixed or hinged, or may be comprised of one or more nested or juxtaposed sections. As can be further observed in fig. 3, the two actuator restraining plates 41 may be interconnected by a plate tie rod 43, the first said plate 41 holding the first intake valve actuator 50 pressed against the first articulated supercharger 1 engaging the upper expansion cylinder head 33, and the second said plate 41 holding the second intake valve actuator 50 pressed against the second articulated supercharger 1 engaging the lower expansion cylinder head 34.

Fig. 1 shows that the restriction device 17 can also consist of at least one booster restriction vise 71 on the burner side, which presses directly or indirectly via at least one vise bearing surface 65 against the booster body 2 in the vicinity of and in the direction of the booster inlet opening 4.

It should be noted that it is conceivable that the same booster restraint vice 71 on the burner side simultaneously presses the respective frusto-spherical end portions 5 on the burner side of the two articulated boosters 1 against the complementary frusto-spherical surface 14 on the burner side with which they engage, the first articulated booster 1 engaging the upper expansion cylinder head 33 and the second articulated booster 1 engaging the lower expansion cylinder head 34.

As shown in particular in fig. 1, it can be observed that the restraining load exerted by the booster restraining vise 71 on the combustor side on the articulated booster 1 engaged therewith can be advantageously set using a vise load setting nut 73, which contains a booster restraining vise spring 72.

The operation of the invention is as follows:

the operation of the hinged supercharger 1 according to the present invention can be easily understood from fig. 1 to 3.

To illustrate the operation in detail, an articulated supercharger 1, which can be used in a transfer-expansion-regeneration internal combustion engine 30 according to patent WO2016/120560 owned by the applicant, is shown in fig. 1 to 3, which is enhanced herein to consist of a double acting expansion cylinder with adaptive support, also described in patent WO2017/046479 owned by the applicant, and allows the expansion cylinder head assembly 35 of said engine 30 to expand freely under the effect of temperature.

It can also be observed in fig. 1 to 3 that the transfer-expansion-regenerative combustion internal combustion engine 30 envisages housing a regenerative cooling system according to patent WO2018/154214, also held by the applicant, in a manner that reinforces said engine 30.

Thus, in fig. 1 to 3, the presence of the cooling chamber 47 and of the air flow space 44 will be noted, these components 47, 44 being characteristic of the regenerative cooling system according to patent WO 2018/154214.

Fig. 3 is an overall view of a transmission-expansion-regeneration internal combustion engine 30 which can conceivably house the articulated supercharger 1 according to the invention.

In said figure 3, a double-acting expansion piston 31 is observed, which can translate longitudinally in an expansion cylinder 32, wherein the upper end is closed by an upper expansion cylinder head 33 and the lower end is closed by a lower expansion cylinder head 34. Thus, the cylinder 32 and the cylinder heads 33, 34 form an expansion cylinder head assembly 35.

It is noted in fig. 3 that the transfer-expansion-regeneration internal combustion engine 30 includes a compressor 36 that compresses a working gas 37. Said gas 37 is intended to be preheated in a regenerating heat exchanger 38, expanded in an expansion cylinder 32 and then superheated by a heat source 39, in this case and according to the non-limiting example disclosed herein for illustrating the operation of the articulated supercharger 1 according to the invention, which is a burner known per se.

Upon expansion, the working gas 37 produces mechanical work on the double acting expansion piston 31 which is transmitted to the power take off shaft 40 housed in the gearbox 45.

It can be observed that the working gas 37 is conveyed from the heat source 39 to the expansion cylinder 32 in sequence via the burner outlet pipe 46 and then via the inlet pipe 3 formed by the supercharger body 2 of the articulated supercharger 1 according to the invention.

In fig. 1 to 3, an intake valve actuator 50 is observed which controls the intake valve 10, this actuator being the hydraulic regenerative valve actuator 51 described in french patent application No. 1759206, 10/2, 2017, which the applicant has. In fig. 3, a hydraulically closed regenerative engine 70 is described in the patent application.

In particular, in fig. 1 and 2, the main components of the hydraulic regenerative valve actuator 51 described in french patent application No. 1759206 can be seen. These components include an actuator jack 52 which contains an actuator jack piston 53 to form a hydraulic actuator chamber 54. According to a non-limiting example of embodiment, hydraulic fluid is introduced into said hydraulic chamber 54 or discharged from said chamber 54 through a tubular hydraulic valve 55 controlled by a solenoid valve actuator 56.

It will be observed that the actuator jack piston 53 acts on the valve stem 11 of the inlet valve 10 via a valve lift cam lever 57 which is connected to said valve stem 11 via a cam lever pivot link 58.

The valve lift cam rods 57 bear against a cam rod rolling slide plate 59, which together act to lift or support the intake valves 10.

It should be noted that the cam lever orientation arch 60 may advantageously maintain its orientation on the valve lift cam lever 57 along an axis parallel to the valve 11.

Fig. 1 and 2 also show a valve return jack 61 for returning the inlet valve 10 to its valve seat, said jack 61 in particular consisting of a valve return jack piston 62 to form a hydraulic valve return jack chamber 63.

Below the cam rod rolling/sliding plate 59, a clearance compensation jack 64 is also observed, which compensates the deformations and expansions of the various components forming the hydraulic regeneration valve actuator 51, so as to enable the latter to operate properly, regardless of the mechanical and thermal stresses to which it is subjected.

It is assumed herein that the expansion cylinder head assembly 35 is maintained at a temperature of seven hundred degrees celsius by the cooling chamber 47 envisaged by the regenerative cooling system according to patent WO2018/154214, while the temperature of the working gas 37 when it leaves the heat source 39 is one thousand three hundred degrees celsius.

It will also be assumed herein that advantageously, thanks to the regenerative cooling system, the expansion cylinder head assembly 35 is made of cast iron, which is a material known for motorization, whether the latter is for motor vehicles, trucks or ships.

It will also be assumed herein that the burner outlet tube 46 and the supercharger body 2 of the hinged supercharger 1 according to the present invention are made of silicon carbide, with an operating temperature equal to the temperature of the working gas 37 leaving the heat source 39, i.e. one thousand three hundred degrees celsius according to the non-limiting example taken herein.

The intake valve 10 is made of silicon nitride in the case of its portion closest to the valve seat 9 with which it is engaged, and is made of steel in the case of its portion where the valve stem 11 enters inside the intake valve actuator 50 and engages with the valve lift cam rod 57.

It should be noted that the part of the inlet valve 10 made of silicon nitride is heated in operation to a temperature substantially close to one thousand three hundred degrees celsius, while the part of the valve stem 11 made of steel is heated in operation to a temperature substantially close to one hundred degrees celsius. It may be specified herein that the portion made of steel of the valve stem 11 is advantageously shrink-fitted onto the portion made of silicon nitride of said valve stem 11.

It will be appreciated that as the expansion cylinder head assembly 35 expands under the influence of its operating temperature of about seven hundred degrees celsius, and the supercharger body 2 and the burner outlet duct 46 likewise expand when subjected to a temperature of about one thousand three hundred degrees celsius, the distance between the frusto-spherical end portion 5 on the burner side and the frusto-spherical end portion 7 on the cylinder head side of the same articulating supercharger 1 increases.

This applies to each of the articulated supercharger 1 shown in fig. 3. From this increase in distance and the various expansions described above, it can be easily inferred that the direction of the articulated supercharger 1 varies, on the one hand, with respect to the upper expansion cylinder head 33 or the lower expansion cylinder head 34 engaged therewith, and, on the other hand, with respect to the burner outlet pipe 46 tightly connected thereto.

The articulated supercharger 1 according to the invention is able to change the relative direction of the supercharger 1, since the frusto-spherical end 5 on the burner side forms a first tight spherical joint link 16 with the complementary frusto-spherical surface 14 on the side facing the same burner. This variation is enabled because the frusto-spherical end portion 7 on the cylinder head side forms a second tight spherical joint link 16 with a complementary frusto-spherical surface 15 on the same cylinder head side facing.

The articulated supercharger 1 according to the invention thus automatically accommodates the variations in distance between the upper expansion cylinder head 33 and the lower expansion cylinder head 34 and between said cylinder heads 33, 34 and the burner outlet pipe 46 to which they are connected via the supercharger body 2 in engagement therewith.

In fig. 3 it can be observed that four intake valve actuators 50, consisting of a transfer-expansion-regeneration internal combustion engine 30, are each supported by the supercharger body 2, said actuators 50 each resting on the supercharger body via an actuator bearing surface 12 contained in an actuator bore 8, which is in engagement with said actuators.

As can be observed in fig. 1 to 3, the thermally decoupled spacer 13 is advantageously interposed between the intake valve actuator 50 and the supercharger body 2 carrying it.

According to this non-limiting example, the thermally decoupled spacer 13 is made of a material with low thermal conductivity, such as zirconia, while its lower part forms a heat-separating plate screen 20, which protects the intake valve actuator 50 from the heat emitted by the working gas 37 circulating at high temperature in the intake pipe 3 formed by the supercharger body 2.

It can be observed in fig. 1 and 2 that in the thermal protection of the intake valve actuator 50 formed by the thermal isolation mesh 20, an actuator body cooling circuit 69 is added in which a heat transfer fluid, such as a mixture of water and glycol, maintained at a temperature of about one hundred degrees celsius, is circulated.

In fig. 1 to 3, a constraint device 17 is shown which, on the one hand, presses the intake valve actuator 50 against the supercharger body 2 in engagement therewith, and, on the other hand, presses the frusto-spherical end portion 7 on the cylinder head side against a complementary frusto-spherical surface 15 on the cylinder head side in engagement with said end portion 7, while pressing the frusto-spherical end portion 5 on the cylinder head side against a complementary frusto-spherical surface 14 on the burner side in engagement with said end portion 5.

In fig. 1 to 3, it can be observed that the restraining means 17, which on the one hand press the inlet valve actuator 50 against the supercharger body 2 and on the other hand press the frusto-spherical end portion 7 on the cylinder head side against the complementary frusto-spherical surface 15 on the cylinder head side, take the form of an actuator restraining plate 41 which applies a pressure load to the inlet valve actuator 50 in the direction of the supercharger body 2 via a plate abutment 42, which here is hinged and consists of several insert parts.

It can be observed in fig. 3 that the two actuator restraining plates 41 are interconnected by tie rods 43, the first said plate 41 pressing the first intake valve actuator 50 against the first articulated supercharger 1 engaging the upper expansion cylinder head 33, and the second said plate 41 pressing the second intake valve actuator 50 against the second articulated supercharger 1 engaging the lower expansion cylinder head 34.

It can be observed in fig. 1 that the restriction device 17 also comprises a booster restriction vise 71 on the burner side, which presses on the booster body 2 in the vicinity of and in the direction of the booster inlet aperture 4 via at least one vise bearing surface 65, which here takes the form of a ball joint link.

Advantageously, the same supercharger restraint vice 71 on the combustor side simultaneously presses the respective frusto-spherical ends 5 on the combustor side of two articulated superchargers 1 included in the same expansion cylinder head assembly 35 against the complementary frusto-spherical surfaces 14 on the combustor side with which they engage, the first articulated supercharger 1 engaging the upper expansion cylinder head 33 and the second articulated supercharger 1 engaging the lower expansion cylinder head 34.

As shown in fig. 1, the restraining load exerted by the booster restraining vise 71 on the combustor side on the articulated booster 1 engaged therewith is adjustable herein and according to this non-limiting example by a vise load setting nut 73 which compresses a booster restraining vise spring 72 which ensures that the pressure load exerted by the booster restraining vise 71 on the combustor side on the articulated booster 1 engaged therewith varies little regardless of the expansion of the various components clamped by the vise 71.

In the same way as the expansion of the expansion cylinder head assembly 35, the hinged supercharger 1 meshing with said assembly 35 and the burner outlet duct 46, the thermally decoupled spacer 13 and the end of the inlet valve 10 made of silicon nitride expand in all directions, even warping, under the effect of mechanical and thermal stresses.

Furthermore, the manufacturing tolerances listed above for the various components 35, 1, 46, 13, 10 mean that the positioning of the intake valve actuator 50 relative to the positioning of the valve seat 9 provided at the level of the supercharger outlet orifice 6 varies depending on the operating conditions of the transfer-expansion-regeneration internal combustion engine 30.

To this end, it is necessary to ensure that the intake valve 10 still rests properly and tightly against the valve seat 9, which is contained within the supercharger body 2 according to the non-limiting example used herein to illustrate the operation of the hinged supercharger 1 according to the present invention.

The relative position of the inlet valve actuator 50 with respect to the valve seat 9 is variable, and the articulated supercharger 1 according to the invention envisages that the valve seat 9 has a complementary frusto-spherical surface 18 on the valve seat side, which is envisaged herein as conical, said surface 18 engaging with a frusto-spherical bearing area 19 provided on the valve side of the end of the inlet valve 10, so that the inlet valve can be oriented with respect to the articulated supercharger 1 according to a limited angle, while in all cases creating tightness with the valve seat 9 with which it engages.

The valve stem 11 of the inlet valve 10 is therefore engaged with an upper stem guide ball joint 66 provided in the inlet valve actuator 50, said valve stem 11 being able to translate in said ball joint 66 along its longitudinal axis, the latter enabling said valve 10 to be oriented according to a limited angle with respect to the inlet valve actuator 50 controlling it.

Additionally, fig. 1 and 2 show that the valve stem 11 may translate along a longitudinal axis within a position memory valve stem seal carrier 67 provided in the intake valve actuator 50.

The position memory stem seal carrier 67 is radially displaceable relative to the actuator 50 when the valve stem 11 exerts a radial load thereon. As can be observed in fig. 1 and 2, said sealing support 67 comprises, on the one hand, a stem seal 74 forming a tightness between itself and the stem 11 and, on the other hand, a sealing support seal 75 forming a tightness between said sealing support 67 and the intake valve actuator 50.

As can be seen in fig. 1 and 2, the position memory stem seal carrier 67 is held against the intake valve actuator 50 by a stem seal carrier spring 68, which here consists of a stack of resilient gaskets.

It will be observed that the pressure load exerted by the spring 68 on the sealing carriage 67 tends to fix the latter by friction in position relative to the actuator 50 of the inlet valve, without preventing it from moving when the valve stem 11 exerts a radial load of sufficient strength on it.

The device for reorienting the inlet valve 10, formed in all the ways described above, allows the supercharger body 2 to warp and expand, the end of the inlet valve 10 made of silicon nitride being elongated, allowing on the one hand the clearance between the thermally decoupled spacer 13 and the inlet valve actuator 50 and on the other hand the clearance between said spacer 13 and the actuator hole 8 to be compensated without affecting the tightness of the formation of the inlet valve 10 with the valve seat 9 with which it engages.

In fact, when, due to expansion, deformation or clearance compensation, the inlet valve 10 is no longer exactly on the axis of the valve seat 9 with which it is engaged after opening, when said valve 10 is closed, the side of the frustoconical supporting region 19 on the valve side first abuts the valve seat 9, which in this case is conical.

The inlet valve 10 continues its closed state, and when the inlet valve 10 is closed, the cone formed by the valve seat 9 returns the frusto-spherical bearing area 19 on the valve side to the centre of said valve seat 9.

In doing so, the valve stem 11 applies a radial load to the position memory valve stem seal carrier 67, causing the latter to move radially relative to the intake valve actuator 50, which is controlled by the upper valve stem guide ball joint 66.

Upon subsequent opening of the intake valve 10, the seal carrier 67 maintains the orientation of the intake valve 10 relative to the actuator 50 until the valve 10 is subsequently closed, due to the pressure load exerted by the valve carrier spring 68 on the position memory valve stem 67, which brakes the latter relative to the intake valve actuator 50.

Thus, the intake valve 10 remains on the axis of the valve seat 9 with which it is engaged, without preventing the various components of the articulated supercharger 1 or the transfer-expansion-regeneration internal combustion engine 30 according to the invention from freely warping and/or expanding in accordance with the operating stresses of said engine 30.

It should be further noted that this strategy of maintaining the intake valve 10 in the correct orientation is advantageously combined with the compensation of the clearance performed by the clearance compensation jack 64, which is described in particular in french patent application No. 1759206, 10.2.2017, held by the applicant.

The possibilities of the hinged supercharger 1 according to the present invention are not limited to the above applications and it should be further understood that the above description is given by way of example only and that it does not in any way limit the scope of the invention, which still applies if any other equivalent described implementation details are substituted.

Claims (8)

1. Hinged supercharger (1) conceived for a transfer-expansion-regeneration internal combustion engine (30), in which a double-acting expansion piston (31) moves in an expansion cylinder (32) forming, together with an upper expansion cylinder head (33) and a lower expansion cylinder head (34), an expansion cylinder head assembly (35), said engine (30) comprising a compressor (36) which compresses a working gas (37) before discharging it into a regeneration heat exchanger (38), in which said gas (37) is preheated, whereas, on leaving said exchanger (38), said gas (37) is superheated by a heat source (39) before being introduced into said expansion cylinder (32) via a burner outlet duct (46) and then an intake duct (3) and through an intake valve (10) controlled by an intake valve actuator (50), in order to expand therein and produce work on a power take-off shaft (40), said gas (37) is subsequently discharged from said expansion cylinder (32) before being reintroduced into said regenerative heat exchanger (38) so as to be cooled therein by transferring part of its heat to said working gas (37) which is preheated in said exchanger (38), said supercharger (1) being characterized in that it comprises:

-a hollow supercharger body (2) forming the intake pipe (3) and comprising a supercharger inlet aperture (4) communicating with the heat source (39), a supercharger outlet aperture (6) opening into the expansion cylinder (32) via the upper expansion cylinder head (33) or the lower expansion cylinder head (34), and an actuator aperture (8) housing the intake valve actuator (50);

-a truncated spherical end (5) on the burner side, provided at the level of the supercharger inlet orifice (4), said end (5) forming a tight spherical joint link (16) with a complementary truncated spherical surface (14) on the burner side, provided outside the burner outlet pipe (46);

-a frusto-spherical end portion (7) on the cylinder head side, provided at the level of the supercharger outlet aperture (6), said end portion (7) forming a tight spherical joint link (16) with a complementary frusto-spherical surface (15) on the cylinder head side, provided outside the upper expansion cylinder head (33) or the lower expansion cylinder head (34);

-a valve seat (9) provided in the vicinity of the supercharger outlet orifice (6), the inlet valve (10) being able to rest on the valve seat (9) to close the orifice (6);

-constraining means (17) which press on the one hand said frusto-spherical end (5) on said burner side against said complementary frusto-spherical surface (14) on said burner side and on the other hand said frusto-spherical end (7) on said cylinder head side against said complementary frusto-spherical surface (15) on said cylinder head side.

2. The hinged supercharger according to claim 1, characterised in that the valve seat (9) has a complementary frusto-spherical surface (18) on the valve seat side, which engages with a frusto-spherical bearing area (19) provided on the valve side of the end of the inlet valve (10), which surface (18) and bearing area (19) form a tight spherical joint link (16) when in contact with each other.

3. The hinged supercharger of claim 2, wherein the intake valve (10) includes a valve stem (11) translatable along its longitudinal axis in or with an upper valve stem guide ball joint (66) housed in the intake valve actuator (50), the ball joint (66) enabling the valve (10) to orient itself according to a limited angle relative to the actuator (50).

4. The hinged supercharger of claim 3, wherein the valve stem (11) is translatable along its longitudinal axis in a position-memory valve stem seal holder (67) housed in the intake valve actuator (50), the seal holder (67) being radially movable relative to the actuator (50) and including a valve stem seal (74) forming a seal between the seal holder (67) and the valve stem (11), and the seal holder (67) further including a seal holder seal (75) forming a seal between the seal holder (67) and the intake valve actuator (50).

5. The hinged supercharger of claim 4, wherein the position memory stem seal carrier (67) is held against the intake valve actuator (50) by a stem seal carrier spring (68).

6. The hinged supercharger of claim 1, wherein the supercharger body (2) accommodates the intake valve actuator (50) via thermally decoupled spacers (13) that create tightness and centering with the supercharger body (2) on the one hand and the intake valve actuator (50) on the other hand.

7. The hinged supercharger of claim 1, wherein the restraint device (17) consists of at least one actuator restraint plate (41), said at least one actuator restraint plate being held pressed against said inlet valve actuator (50) by at least one plate tie (43) and via at least one plate abutment (42), such that the actuator (50) is in turn held pressed against the supercharger body (2) via an actuator bearing surface (12) contained in the actuator bore (8), and such that the frusto-spherical end portion (5) on the burner side is held pressed against the complementary frusto-spherical surface (14) on the burner side and/or the frusto-spherical end portion (7) on the cylinder head side is held pressed against the complementary frusto-spherical surface (15) on the cylinder head side.

8. The articulated supercharger of claim 1, characterised in that the restraining means (17) consists of at least one supercharger restraining clamp (71) on the burner side, which presses directly or indirectly via at least one clamp bearing surface (65) against the supercharger body (2) in the vicinity of and in the direction of the supercharger inlet aperture (4).

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