EP2356318A1

EP2356318A1 - Rotary machine of the deformable rhombus type comprising an improved transmission mechanism

Info

Publication number: EP2356318A1
Application number: EP09760928A
Authority: EP
Inventors: Vincent Genissieux; Jean-Thomas Collomb; Jean-Pierre Ambert
Original assignee: Ambert Jean-Pierre; Collomb Jean-Thomas
Current assignee: Ambert Jean-Pierre; GENISSIEUX, VINCENT
Priority date: 2008-11-12
Filing date: 2009-11-09
Publication date: 2011-08-17
Anticipated expiration: 2029-11-09
Also published as: WO2010055223A1; US8951028B2; FR2938291A1; US20110280757A1; FR2938291B1; EP2356318B1

Abstract

Rotary machine of the deformable rhombus type comprising a. a rotor (3) which is a deformable rhombus (4) in contact with the inner surface of an enclosure (1) forming a stator (2), said deformable rhombus (4) comprising four pistons (6) connected, in mutual succession, by a pivoting articulation (7) and thus forming a closed chain; and b. a transmission mechanism (14) for transmitting the movement between the pistons (6) and a rotary shaft (15) coaxial to the central axis of the machine, characterized in that said transmission mechanism (14) comprises: a first bearing body (16) mounted fixedly on at least one piston (6), preferably on each piston (6), the axis of said first bearing body (16) passing at the centre of the piston (6) and connected to a second bearing body (19) of which the centre passes through the central axis of the machine and is secured to said rotary shaft (15), the first bearing body (16) being connected to the second bearing body (19) directly or via an intermediate transmission member (18) - and in that the reduction ratio of the first (16) to the second bearing body (19) is equal to 2 and is positive.

Description

DEFORMABLE LODGE ROTATING MACHINE HAVING A MECHANISM

OF PERFECTIONED TRANSMISSION

Field of the invention

The present invention relates to a rotary deformable diamond machine (MRLD) and more particularly relates to a transmission mechanism for such a machine. A rotary machine with deformable rhombus generally comprises a stationary assembly or stator and a moving assembly or rotor having a diamond shape articulated at its vertices and rotating around its center, able to deform in particular during its rotation. Each side of the diamond determines, with the internal profile having a generally oval shape of the stator, a chamber of variable volume during the movement of the rotor. The sides of the articulated diamond are materialized by plates called pistons having an outer surface of generally curvilinear shape. These pistons are sometimes provided, in their area of contact with the internal profile of the stator, sealing segments. Such a machine can be used as a combustion engine, turbine, compressor, pump, metering device, grinder, mixer, loaded fluids or not. It has the advantage of having a fixed center of gravity, thus being able to avoid vibrations, to be able to reach compressions equivalent to those of piston engines, to have a higher flow rate than piston engines, to have a higher pressure ratio than that of turbines and to be simpler than most generally known machines performing the same functions.

State of the art

Deformable diamond rotating machines (MRLD) have a stator generally consisting of a cylindrical non-circular enclosure (it includes a cylinder whose direction is not a circle) external to the diamond-shaped rotor. The rotor comprises a plurality (usually four) of rotary elements articulated to each other at their adjacent edges in a pivot connection axis parallel to the longitudinal axis passing through the center of the enclosure, each of the rotating elements defining with the inner wall of the chamber a chamber or cavity of variable volume. These machines have been described for a long time, but they are hardly used. Like the Wankel engine, well known to those skilled in the art, these machines had been imagined first as a combustion engine. The patent FR 1 404 453 (J. Lemaitre), the US Pat. No. 3,196,854 (A. Novak), the patent FR 2,145,133 (J. Martin Artajo) the patent application WO 01/88341 (P. Szorenyi), the patent CA 997998 (E. Steinbrink) and patent application FR 2 493 397 (JP Ambert) describe the idea and theoretical design of such an engine. Patent application WO 2004/070169 (G. Saint-Hilaire) describes a deformable rhombic internal combustion engine by detailing its structure, but without explaining how its sealing is ensured under the operating conditions of an internal combustion engine, also without detailing the materials able to withstand the pressures and temperatures in such a machine, nor provide solutions concerning the expansion of materials, or the compensation of functional clearances. Other MRLD type explosion engines are described for example in EP 1 295 012 B1 (Nivesh SA), and US 3,387,596 (L. Niemand).

When the MRLD is working as a rotary motor, the rotational torque of the rotor must be recoverable by a transmission shaft so that it can be used by a related device, for example via a gearbox, by the wheels of an automobile . When working as a compressor or rotary pump, the movement must be able to be printed on the rotor from a central transmission shaft. Several documents describe solutions for such transmission mechanisms.

The document FR 2 493 397 (J. P. Ambert) describes a rotary engine that can operate as an internal combustion engine or as a pump or compressor comprising four articulated pistons forming a deformable rhombus which are articulated in their middle on two cranks with two opposite arms. One of the cranks drives a transmission shaft centered in the stator, the other crank being rotatably mounted around the same shaft, due to the fact that the angle between the two cranks varies during the deformation of the rhombus. This solution using the transmission of the movement only by a median arm does not ensure a uniform velocity movement of the diagonals of the diamond, which can induce parasitic torque due to the dynamics of the machine resulting in a non-uniform rotation of the central tree.

US 3,369,529 (A. Jordan) discloses an internal combustion engine with articulated rotary pistons for forming a deformable rhombus within an oval cross-section enclosure and a mechanism for transmitting the movement of pistons to a central shaft, the transmission mechanism comprising four separate arms integral with the shaft, each being arranged between the shaft and a hinge roller and being of radially variable length. Assuring certainly a more uniform rotation of the central shaft, this solution has the disadvantage of not providing support to the pistons to withstand the significant forces of traction or compression; pistons which are thrown against the inner surface of the stator. Such a solution can lead to premature wear of the components of the machine, with the appearance of games that can ultimately affect the proper functioning of the machine.

FR 2 374 512 (A. Jordan) discloses an internal combustion engine with rotary pistons, comprising in particular four articulated pistons, which can oscillate in rotation, rigidly applied at their end by articulating rollers and bearing rollers. seal, against the inner surface of an inner chamber and having a mechanism for transmitting the forces of the pistons to a central shaft. The transmission mechanism comprises a pair of arms integral with the central shaft and a pair of arms rotatably mounted about the shaft, each pair of arms being hinged in the middle of a piston, as well as four other arms. separate from the central shaft, connecting the central shaft to the hinge rollers and being of radially variable length. The transmission mechanism of this document ensures, of course, a uniform rotation of the central shaft and, at the same time, a support of the pistons during the engine cycle, but at the risk of generating friction losses at the slides, while being cumbersome and of complex construction.

Moreover, the document WO2004 / 070169 (G. Saint-Hilaire) proposes a solution of mechanism for transmitting the torque between the pistons of a rotary machine with deformable rhombus and a central shaft thereof, where the transmission mechanism presents a smaller footprint. The transmission mechanism comprises two power rings arranged axially one in line with the other in the center of the rotor of the machine, each ring receiving torque from two bearing rollers connected to two opposed pistons. The movement of each power ring is transmitted to a central shaft by means of a tangential differential formed by four curved washers mounted on a central shaft and whose protuberances are inserted into slots of the power rings. Being, of course, of more compact construction than the mechanism of the previous document, it is clear that the solution described in this document can only transmit low torques, while requiring good control of the functional clearances between the multiple moving parts relative and that, by the use of transfer protrusions, the life of such a complex mechanism is very limited.

The document US2003 / 062020 (P.D. Okulov) describes a deformable diamond rotating machine comprising four pistons interconnected by an articulated parallelogram which are caused to oscillate in rotation during their movement inside an ovoid-shaped enclosure. This document also illustrates several solutions of mechanisms for transmitting the movement between the pistons and a central transmission shaft. Among these solutions, there is one having a toothed wheel integral with a central shaft which is caused to mesh with pinions mounted in the center of each piston. However, due to the speed variation between the different gears, the latter can not be all integral in rotation of the pistons. Thus in the case where two gears are integral in rotation of opposed pistons and the other two are free in rotation, the mechanism can not transmit a uniform rotation to the shaft which therefore receives only the torque from the two opposed pistons. In the case where a single pinion is integral with the piston and the other three are free to rotate, the torque often important in this type of machine, is transmitted only by a single pinion, which could strongly damage its teeth. If two contiguous piston gears are attached to the pistons, then the transmission can not work. Another solution describes a Maltese cross type mechanism mounted fixed on the central shaft, and having slits in which rollers belonging to the arms connecting each rotary joint to the shaft slide. This mechanism ensures, of course, a more uniform rotation of the central shaft, but at the cost of significant friction in the sliding links of the slots of the device, which leads to losses in the transmission of torque to the shaft.

Object of the invention

The object of the invention is to overcome the aforementioned drawbacks and to propose a deformable diamond rotating machine comprising a transmission mechanism capable of transmitting the torque between the diamond and the central or peripheral transmission shaft to the diamond so as to ensure a uniform rotation speed of the drive shaft.

Another object of the invention is to propose a rotary deformable diamond machine comprising a mechanism for transmitting motion between the diamond and the shaft. central or peripheral transmission capable of ensuring a good performance of the transmission, while providing reliable operation and having an improved life.

Another object of the invention is to propose a deformable diamond rotating machine with reversible operation comprising a transmission mechanism capable of transmitting the torque between the diamond and the central or peripheral diamond transmission shaft, for a speed of uniform rotation of this tree.

Another object of the invention is to provide a rotary deformable diamond machine having a mechanism for transmitting the movement between the rhombus and the central or peripheral transmission shaft of simplified and compact structure, while being able to be achieved economically.

These objects are achieved with a rotary deformable diamond machine comprising: a) a rotor which is a deformable rhombus which is directly or indirectly (via a seal or the outer surface of a pivoting joint) in contact , with or without clearance, with the inner surface of an enclosure forming a stator and / or with the outer surface of a central ring, said deformable rhombus comprising four connected pistons, one after the other, by a pivot joint with an axis parallel to the longitudinal axis of the enclosure and thus forming a closed chain; and b) a mechanism for transmitting the movement between the pistons and a rotational shaft coaxial with the central axis of the machine, said machine being characterized in that said transmission mechanism comprises:

- A first rolling body fixedly mounted on at least one piston, preferably on each piston, the axis of said first rolling body passing in the center of the piston - a second rolling body whose center passes through the central axis of the machine and is integral with said rotation shaft

the first rolling body being connected to the second rolling body directly or by a transmission member

- And that the gear ratio between the first and the second rolling body is equal to 2 and is positive. The machine thus comprises four articulated pistons forming a deformable rhombus, the deformation of the rhombus being able to take place when it rotates inside a fixed enclosure surrounding the rhombus or, when it turns around a fixed central crown arranged at the inside of the rhombus, or when the enclosure or the ring rotates relative to the fixed diamond in rotation. By central axis of the machine is understood the longitudinal axis of rotation of the machine which is parallel to the director of the enclosure, the enclosure being generally symmetrical with respect to this longitudinal axis.

According to the invention, the machine comprises a transmission mechanism between the diamond, in particular its pistons, and the rotation shaft of the machine. More particularly, said mechanism comprises, for at least one piston, preferably for each piston, a first rolling body mounted in the center of the piston which is in direct contact with or connected by a transmission member to a second body. running on the rotating shaft of the machine. By rolling body, there is a generally cylindrical piece, which may be a cylinder or a cylinder portion. In a simplified version of the invention, the transmission mechanism can operate with a single first rolling body mounted on a single piston, or with only two or three first rolling bodies mounted on respectively two or three pistons. This constructive simplification is of economic interest because it makes it possible to reduce the cost of producing the transmission mechanism. It is preferred, however, to mount a rolling body on each piston to provide a well-balanced transmission mechanism assembly with good rotor guidance for improved machine life.

According to the invention also, the first rolling body and the second rolling body are connected either directly in contact, it is understood that the movement is transmitted directly from one rolling body to the other, for example using a obstacle or friction drive, either by an intermediate part, in particular by using a transmission member. By transmission member, there is a device or part for transmitting the torque and the rotational movement of the first rolling body located at a distance from the second rolling body. Such a transmission member between two rolling bodies may include an intermediate rolling body or an assembly comprising intermediate rolling bodies. By way of example, this transmission member may be a chain, a belt, etc. Such a rolling body arrangement is particularly advantageous because during the deformation of the diamond, the median length of this diamond does not change, so we can greatly simplify the design and structure of the transmission mechanism.

According to the invention also, the gear ratio between the first and the second rolling body is positive and is equal to two. Indeed, the arrangement of the elements of the transmission on a median must take into account that the angle between the medians is variable with the deformation of the diamond. Therefore, the mechanism of the invention involves the use of a reducer on each median segment connecting the center of a piston in the center of the rhombus. This reducer uses a geometric property of the deformable rhombus implemented by the invention, which is the fact that, during the deformation of the rhombus, the angle of rotation of a median due to this deformation of the rhombus is half of the angle between the side of the diamond and the median. The geometric principle on which the operation of the transmission mechanism of the invention is based is better described in the following, in the detailed part of the description.

The transmission mechanism of the invention thus makes it possible to transmit both the rotational torque of the pistons around the center of the machine and the tilting torque of the pistons around their center to the rotation shaft in engine or turbine mode and conversely when the machine is running in compressor or pump mode. A MRLD according to the invention can be used for pumping, turbining, compressing, relaxing, grinding, dosing, mixing filled or unloaded fluids, using means connecting it to a fluid circuit external to the machine, or else being used as a motor internal combustion engine of a mixture of fuel and oxidant.

The transmission mechanism of the invention thus makes it possible to correctly transmit the torque between each piston of the rhombus and the rotation shaft of the machine, while ensuring a uniform rotational speed of this shaft, and this in the context of a Simplified construction and energy efficient.

Preferably, said first rolling body and said second rolling body are provided with driving protuberances on at least a part of their periphery.

Such a transmission member having driving protrusions forms a drive by contact and transmits power by obstacles. This ensures a synchronous motion transmission, so no slip, silent and with a good energy efficiency between each piston and the machine rotation shaft. Thus, when the pressure inside the chambers of the machine (per chamber is understood the volume between the enclosure surrounding the diamond and the extrados face of a piston, or any other cavity with variable volume arranged in the machine ) is not homogeneous, or when the pistons undergo reaction forces in contact with the guide surface of the enclosure, or when they undergo different dynamic effects due to the kinematics of the machine, the forces acting on a piston can create a tilting torque of the piston around its center. This tilting torque of the pistons is transmitted to the rotation shaft via the driving protuberances.

Advantageously, said transmission mechanism comprises gears with parallel axes and right teeth.

The transmission mechanism of the invention therefore uses a mechanical system consisting of gear wheels for transmitting the rotational movement. Gears with parallel axes and straight toothing are preferred because they offer a solution allowing high torque transmission without introducing axial forces and this in an economical manner.

However, for embodiments of silent machines will be used preferably for the transmission mechanism of the invention gears parallel axes and helical gears. In this case, it is possible to compensate the axial forces by superimposing gears whose tooth angles are reversed.

In a preferred embodiment of the invention, the first rolling body is a half-pinion integral with a piston which meshes with a toothed wheel forming the second rolling body integral with the central rotation shaft of the machine by means of an intermediate rolling body forming a satellite gear.

This solution allows an efficient transmission of the rotational movement between the pistons of the diamond and a rotation shaft, ensuring a uniform speed of rotation of the shaft located in the center of the machine, for a good energy efficiency, while being able to be performed for a low cost. In another variant of the invention, said first rolling body is a conical gear connected to said second rolling body which is a conical gear by a shaft provided with bevel gears at the ends. The transmission member between the first and the second rolling body is a shaft provided with bevel gears at each of its ends. The gear made between this shaft and the first rolling body is comparable to a gearbox with a bevel gear. It is the same for the gear made between this shaft and the second rolling body. The intermediate transmission member is an axle shaft arranged in a radial direction (in the case of single conical teeth), perpendicular to the longitudinal directions of the axes of the pinion (integral with the piston) and the conical toothed wheel (integral with the rotation shaft). This embodiment also makes it possible to release the dimensional constraints of the diamond because the distance between the two bevel gears of the intermediate shaft is no longer related to the dimensions of the toothing and can therefore easily vary. This solution makes it possible to produce very large machines with a transmission that remains rigid, light and compact.

In another advantageous embodiment of the invention, said first rolling body is a toothed circular sector attached to a piston which meshes with a toothed ring gear with internal teeth secured to the rotation shaft.

This solution allows a direct gear drive between the diamond pistons and a peripheral ring gear with a positive gear ratio, without the need to add intermediate planet gears. In addition, a ring gear drive with internal teeth has a larger diameter, with more teeth in contact and can therefore transmit a larger torque.

Preferably, the ring gear has a cylindrical peripheral contour and the toothed sectors are arranged one in the extension of the other so that they form a deformable inner ring of width (in the radial direction) greater than that a chamber of the machine, in order to close these rooms with variable volume. The cylindrical peripheral contour of the ring gear promotes the transmission of the rotational movement and the integration of the machine.

By making the toothed sectors integral with the pistons whose lateral face is placed towards the inside of the machine, it makes it possible to close the outer chamber of the machine and this on the periphery of the enclosure.

Advantageously, the machine comprises a cavity internal to the diamond for moving a fluid or receiving an element outside the machine.

Thus, by arranging the constituent elements of the transmission mechanism on the outer lateral sides of the pistons, the central space of the rhombus (space defined by the internal faces of the pistons, called the intrados faces) forms, during the deformation of the diamond, a cavity Internal variable volume. This internal cavity disengaged from the transmission mechanism, can then be used to perform a function complementary to the machine, such as that of pumping a fluid, or it can be used to receive other elements of the installation operating with the machine of the invention to obtain even more compactness of the assembly.

Advantageously, the transmission mechanism can divide the space of the central cavity or other cavities, provided that the transmission members used oppose a sufficient brake to the passage of the fluid. Indeed, the transmission gear, is very close to the conditions of realization of the gear pumps. Likewise, the friction roller transmissions are close to the lobe pumps without external synchronization.

The separations thus created serve to form a number of variable volume internal cavities for pumping, compressing, rotating, or moving fluid, but also for amplifying volume variations or for limiting dead volumes.

In an advantageous embodiment of the transmission mechanism of the invention, said first rolling body and said second rolling body are connected by a chain or a toothed belt.

This solution provides a distance drive between the rolling bodies, without using intermediate rolling bodies, which has the main advantage of obtaining a transmission mechanism according to the invention that can be dimensioned so that it is independent of the distance between the first and the second rolling body. This can make it easier to adapt to an imposed dimension of the machine. In another advantageous embodiment of the transmission mechanism of the invention, said first rolling body is connected to said second rolling body by a smooth belt. This embodiment of the transmission mechanism allows easy installation and assembly inside the machine, while providing the possibility of a fine adjustment of the angular positions of the components.

Preferably, the first two opposite rolling bodies are connected to the second rolling body by a common chain or a common belt; or all the first rolling bodies are connected to the second rolling body by a common belt or a common chain.

It is thus possible to obtain a simplified construction of a transmission mechanism, while being able to transmit more torque between the pistons and the rotation shaft of the machine.

Advantageously, said first rolling body and said second rolling body are friction rollers each having a hard core covered with a flexible envelope.

Such a friction roll transmission mechanism which may each comprise a hard core covered with an adherent flexible envelope is desirable for applications requiring transmission of low torques, but with higher requirements of uniformity of transmission and absence of noise. of operation thereof.

Preferably, said first rolling body is connected by at least one intermediate rolling body to said second rolling body.

This makes it possible to produce a transmission by a rigid rolling contact, the intermediate rolling body making it possible to maintain or obtain a positive gear ratio.

Advantageously, two opposed pistons are connected together by at least one median arm, each end of said median arm being pivotally mounted in the center of each piston. By imposing a value of the game in the pivoting joints of the median arms lower than that of play in the joints of the pistons, these arms medians then allow to support the radial forces acting on the pistons and ensure the proper functioning of the transmission mechanisms.

Advantageously, the transmission mechanism has a reversible operation.

It would have been possible, of course, to use a mechanism for transmitting the movement between the piston and a rotation shaft in one direction, for example by using an assembly of the type gearwheel and worm. However, it is preferred to use a mechanism where the transmission of movement can be made from the pistons to the rotation shaft and vice versa, as this allows a reversible operation of the machine. Furthermore, the low reduction ratio between the first rolling body and the second rolling body facilitates the use of reversible mechanisms.

Preferably, the piston and said first rolling body form a single piece. This solution is preferred because it provides more ease of mounting the transmission mechanism within the machine, and also when the pistons are subjected to heavy stresses.

Advantageously, the transmission mechanism makes it possible to separate an internal cavity of the machine into one or more cavities of variable volume.

Thus, by arranging the transmission mechanism in an internal cavity of the machine, and when the transmission between the piston and the central rotational shaft is by means of gears or friction rollers, these elements of the transmission mechanism can divide the internal cavity of greater volume in one or more cavities of smaller volume, the volume being variable with the deformation of the diamond. This makes it possible, by performing arrangements for sealing inside one or these chambers and connecting it or connecting them to one or more fluid circuits, to assign an additional function, for example a pump, to this device. or these cavity (s) with variable volume thus obtained.

Description of figures

Figure 1 illustrates a schematic view illustrating the principle on which the invention is based.

Figure 2 illustrates a cross-sectional view of the inner part of the machine comprising a transmission mechanism produced according to the invention.

Figures 3 to 9 illustrate different variants of a transmission mechanism according to a first embodiment of the invention, where:

- Figure 3a is a cross-sectional view in perspective of the internal part of a machine having a transmission mechanism according to a first embodiment; Figure 3b is a perspective view of the machine of Figure 3a; Figure 3c is a perspective view of a machine of Figure 3a completed by a stator; Figure 3d is a perspective view of a machine of Figure 3b completed by a stator; FIG. 4a is a sectional view along a plane containing the axis of rotation and a median of the machine illustrated in perspective of the internal part of a machine comprising a transmission mechanism according to a second variant embodiment and FIG. 4b. is a top view of the machine of Figure 4a without the median arms; FIG. 5a is a cross-sectional view in perspective of the internal part of a machine comprising a transmission mechanism according to a third variant of the invention and FIG. 5b is a perspective view of the machine of FIG. 5a. ;

FIG. 6a is a perspective cross sectional view of the internal part of a machine comprising a transmission mechanism according to a fourth variant of the invention and FIG. 6b is a perspective view of the machine of FIG. 6a. ; Figure 6c is a perspective cross-sectional view of the inner portion of a machine having a transmission mechanism according to another alternative embodiment derived from that of Figure 6a;

FIG. 7a is a perspective cross-sectional view of the internal part of a machine comprising a transmission mechanism according to a fifth variant of the invention and FIG. 7b is a perspective view of the machine of FIG. 7a. ; FIG. 8a is a perspective cross-sectional view of the internal part of a machine comprising a transmission mechanism according to a sixth variant of the invention, and FIG. 8b is a perspective cross-sectional view of the machine. of Figure 8a, in a sectional plane showing the entire transmission mechanism; Fig. 9a is a planar cross-sectional view and Fig. 9b is a perspective cross-sectional view of the inner portion of a machine. comprising a transmission mechanism according to a seventh variant of the invention, FIG. 9c being a perspective view of the machine of FIG. 9b; Fig. 10a is a planar cross-sectional view and Fig. 10b is a perspective cross-sectional view of the inner portion of a machine having a transmission mechanism according to an eighth variant of the invention, Fig. 10c being a perspective view of the machine of Figure 10b.

FIGS. 11a to 11d illustrate a transmission mechanism according to a second embodiment of the invention, FIGS. 11a and 11b being front views in two different positions of the diamond of the machine comprising the transmission mechanism; Figure 11c is a perspective view of the machine of Figure 11b and Figure 11d is a longitudinal sectional view of the machine of Figure 11c. Figures 12a and 12b illustrate cross-sectional views illustrated in perspective and Figure 12c is a perspective view of an example of application of a machine having a transmission mechanism according to the first embodiment of the invention.

List of landmarks

Detailed description of the invention

The invention relates to a rotary machine with deformable diamond (MRLD) which can for example function as a motor or as a compressor. The machine comprises, as best seen in FIG. 3d, a stator 2 having a generally tubular shape of approximately oval section, whose profile is in accordance with the geometric rules imposed by the deformation of the diamond during its rotation and whose internal surface defines an enclosure 1 for receiving a rotor 3 which is a deformable rhombus 4. The deformable rhombus 4 is a set of four pistons 6 interconnected by pivot links, materialized by pivoting joints 7, and forming a chain closed on itself. The rotor 3 which is the rotating part of the machine is generally the diamond 4, but it is possible, in a variant, to drive the chamber 1 in rotation which then rotates relative to the rhombus 4 fixed in rotation, but whose sides are deformed. (We understand by side the segment that connects, in a plane perpendicular to the axis of rotation of the machine, the axes of two adjacent pivot links). The projections of the axes of pivotal connections of the pistons in a plane perpendicular to the axis of rotation of the machine represent the vertices 5 (fig.2) of the rhombus 4. In a variant not shown in the figures, the deformation of the rhombus 4 may also take place by guidance around a central ring, fixed or movable in rotation, arranged inside the rhombus and whose profile is in accordance with the geometric rules imposed by the deformation of the rhombus. A piston 6 is a part having a shape of cylinder portion of director parallel to the axis of rotation of the machine. The surfaces located at the two ends of this piece each provide a part of a rotational axis pivot connection parallel to the axis of rotation of the machine. The segment that connects two midpoints of opposite sides of the rhombus, including two opposed pistons, forms a median of the rhombus. The segment that connects two opposing vertices 5 forms a diagonal of the rhombus. The center of the pistons is the middle of one side of the rhombus, it is the junction point with the medians of the rhombus. The intersection of the diagonals or medians of the diamond defines the center of the machine through which the central axis of the machine passes. By rotation shaft 15 of the machine, it includes a part or a set of mechanical parts to recover or impose the rotational movement of the rotor or the stator via a mechanical transmission system 14 adapted. The machine also comprises two lateral closing flanges (not shown in the figures), arranged perpendicularly to the rotation shaft of the machine and bearing against the front and rear end faces of the stator 2 and the rotor 3.

In what follows, the extrados face 9 of the piston 6 comprises the external surface of the piston 6, located outside the rhombus 4, and by the intrados face 11 of the piston 6, the internal surface of the piston 6, located at inside the diamond 4 (fig.3d). The extrados face 9 of a piston 6 defines with the enclosure 1 and the lateral closure flanges an external cavity 8. Two fluid inlet ports 12 and two fluid outlet ports 13 are, in the examples shown in FIGS. 3c, 3d, 11c, 12a, 12b and 12c), radial channels made through the chamber 1 and allowing a fluid exchange between the outer cavities 8 and a fluid circuit outside the machine.

A fluid circuit is connected to the machine, the entrance to the external chambers 8 being illustrated, for example, by an orifice 12 in communication with the input or upstream circuit of the machine, and the fluid outlet being illustrated, for example, by an orifice 13 which is, him, in communication with an output circuit or downstream of the machine. The intrados faces 11 of the pistons 6 (FIG. 3d) define, with their connecting joints 7 and with the lateral closure flanges, an internal cavity 10 of variable volume.

According to the invention, the machine comprises a mechanism 14 for transmitting the movement between the pistons 6 and a rotation shaft 15 coaxial with the central axis of the machine, since said transmission mechanism 14 comprises, for each piston 6, a first rolling body 16 fixedly mounted on the piston 6, the axis 17 of said first rolling body passing in the center of the piston 6, the first rolling body 16 being connected to the second rolling body 19 directly or by means of an intermediate transmission member 18 (FIG. 2) for transmitting the rotational movement from said first rolling body 16 to the second rolling body 19 (FIG. 3a), the center 20 of which (FIG. central axis of the machine and is integral with said rotation shaft 15, and wherein the gear ratio between the first 16 and the second rolling body 19 is equal to 2 and is positive.

Figure 1 illustrates the geometric principle underlying the design of the transmission mechanism of the invention. The deformable rhombus 4 is schematically represented in two operating positions of the machine, during the rotation of the rhombus around its center O, a side PR of the rhombus in the first position taking the position P ¹ R 'in the second position . It demonstrates that when the median OM rotates from an angle α to reach the position OM ', the angle OMR between the diamond side and the median varies from an angle 2α to reach the position OM'R'.

Figure 1 shows that:

(1) ^" MOM ^ α = γ-β

(2) OMR = π - 2 * (τr / 2 - β) because OMR is an isosceles triangle.

(3) ^" OM ^ ^1" = π - 2 ^* (π / 2 - Y) because OM'R 'is an isosceles triangle. We draw relations (2) and (3) that: (4) -UJvVFr-OIvIR ^ 2 * (π / 2 - β) - 2 * (τr / 2 - Y) = 2 ^* (Y - β) We obtain relationships (4) and (1) that: (5) -ύK / PFt

Thus, the geometric relationships above that flow in association with the figure

1 show that, when the median (represented by the segment OM) rotates, with respect to the diagonals, by an angle α, the angle between the side of the rhombus (represented by the segment PR) and the median varies by 2α.

The geometry of the rhombus therefore imposes that the speed of rotation of one side of the rhombus (represented here by the segment PR) with respect to its median (represented by the segment OM) which connects it to the center of the machine (O), on the rotation speed of this median (OM) is two and is positive.

The rolling bodies 16, 19, which may alternatively be gears composed of externally toothed gears, reverse the direction of rotation. In this case, an intermediate body 21 forming a satellite gear is used which essentially serves to maintain a positive speed ratio. The rolling bodies 16,21 arranged according to the median OM in the first position of the rhombus 4, take the references 16 ', 21' being arranged according to the median OM 'in the second position of said rhombus.

The ratio of pitch diameter between the piston pinion and the pinion of the rotation shaft is 2 to comply with the geometric rule related to the geometry of the deformable rhombus.

An example of putting the above principle into practice is better visible in the figure.

2 where the first 16 and the second rolling bodies 19, as well as the intermediate rolling bodies 21 are provided with teeth on their periphery, so that the intermediate transmission member 18 is a gear device.

In a first variant of a first embodiment, as seen in FIGS. 3a to 3d, the first rolling body 16 is a half-pinion integral with an axis 17 which is fixedly mounted in the center of a piston 6, its teeth being oriented towards the center of the diamond 4. In a preferred variant embodiment (FIG. 2), the half-pinion constituting the first rolling body 16 and the piston 6 are made in a single piece, advantageously produced by a method wire EDM in a block of isotropic material for small series or by sintering for large series. When the first rolling body 16 is a block attached to the piston 6, it is then possible to set up an angular offset mechanism between the reported block and the piston, in order to compensate for the play that may exist in the gears of the transmission. 14. Conversely, when the first rolling body 16 and the piston 6 are monobloc, it is necessary that the second rolling body 19 or the intermediate transmission members 18 are able to compensate the angular clearance existing in a gear assembly . In the latter case, it is possible to use idler gears. By way of example, the half-pinion of the first rolling body preferably comprises between 20 and 40 teeth uniformly distributed over its entire periphery, or between 10 and 20 for the half-pinion as shown in the figures. Only certain teeth are useful, depending on the degree of deformation of the diamond.

The second rolling body 19 is a toothed wheel rotatably secured to the rotation shaft 15 passing in the center of the rhombus 4, for example by fixing it to the latter by means of a key 22. The second rolling body 19 is a wheel toothed having a number of teeth equal to twice the number of teeth of the first rolling body 16 or half-pinion, and preferably comprised between 40 and

80 evenly distributed on the periphery, but where only some teeth are useful, depending on the degree of deformation of the diamond.

Intermediate rolling bodies 21 are planet gears having the same module as the half-gears and the gear wheel and which serve to reverse the direction of rotation between the half-gears and the toothed wheel. Their diameter, respectively their number of teeth are chosen according to the size of the machine, in particular according to the dimensions of the diamond 4.

As best seen in FIGS. 3b and 3d, two opposed pistons 6 are connected together by a median arm 23 and the other two opposite pistons 6 of the rhombus 4 are connected together by another median arm 24, where each of the ends of the median arms 23 24 is pivotally mounted at the center of each piston 6. The medial arms 23, 24 are arranged in pairs, one behind the other at each end end of the rhombus 4. More particularly, with reference to FIG. median 23,24 is a generally oblong piece, having a prominent central portion extending, on either side, by two elongate ends, upper 27 and lower 28. The protuberance has a central opening 26 through which passes with or without play the central shaft 15. Each end 27,28 is pivotally mounted about an upper pivot axis 29, respectively lower 30, passing through the center of each piston 6. A flared release 25 is arranged in the intrados face of the piston 6 and around each axis 29,30 to allow the deflection in pivoting of each median arm 23,24. Each median arm 23,24 carries a support pin 31 on which is mounted the intermediate rolling body 21 forming a satellite pinion. Each satellite pinion is mounted on the median arm that connects two opposed pistons. Thus, a satellite rotates on its axis only when the piston revolves around its center (middle of one side of the rhombus). When the diamond 4 rotates in the chamber 1, even without deformation of the diamond 4, the satellites transmit this rotation to the rotation shaft 15 and, conversely, the rotation of the rotation shaft 15 causes the diamond 4 to move.

The half-gears, the planet gears and the toothed wheel are chosen from the right-hand spur gears for their good performance, for the low cost of this type of standard components, and because of the absence of axial forces and particularly when the noise pollution constraints are low. In an advantageous embodiment, the helical teeth are preferred which ensure a progressive contact, therefore a more regular and less noisy operation. It is possible to compensate the axial forces generated by the helical gears by setting up two helical gears superimposed with opposite helix angle.

It is also preferred to contact gears of the same module, and choose a pitch diameter of the planet gears which is close to the pitch diameter of the piston pinions to optimize their wear resistance. Moreover, in order to optimize the efficiency of the transmission, to increase the value of the transmittable torque and to reduce the wear of the gears, maximum pitch diameters are chosen. These being limited by the bulk of the diamond 4. It is possible, in an alternative embodiment (not shown in the figures), to use satellite gears each consisting of two superposed gears. In another variant embodiment (not shown in the figures), it is possible to shift the axis of rotation of the satellite gears with respect to the medians of the diamond. The gears of the invention are dimensioned so as to take into account the specific constraints which they undergo, in particular due to the fact that all the teeth do not work, that the working teeth are stressed mainly in bending in the two orthoradial directions, and in a different way, and that the contact pressures are not during the cycle. Thus, it is preferable, when designing the mechanism and the dimensioning of the gears, to take into consideration the most demanding operating cases (irregularities, shocks, vibrations, oscillations), and to refer to the service life (number cycles) of each tooth.

In a variant (not shown in the figures), to take different tooth modules and free from geometric constraints, it is also possible to make an intermediate body 21 composed of two superimposed teeth whose first gear meshes with the first body of bearing 16 and whose second toothing meshes with the second rolling body 19.

In a variant (not shown in the figures), the toothed wheel, the four half-gears and the planet gears may have teeth only on a part of their periphery at their respective meshing, which offers more freedom in the choice of the pitch of their teeth.

In a second variant embodiment shown in FIGS. 4a and 4b, the first rolling body 16 is a conical half-pinion 53 integral with a piston 6 and the second rolling body 19 is a conical toothed wheel 54 integral with the central rotating shaft of the machine. The teeth are not shown for a better readability of the figures, however, the representation of the contact cones facilitates the understanding of the mechanism. The median arms have been removed from Figures 4b to better see the internal elements. The intermediate transmission member 18 between the first rolling body 16 and the second rolling body 19 is an intermediate shaft 55 provided with bevel gears at each of its ends, in particular an upper conical pinion 56 and a lower conical pinion 57. upper end 56 and lower 57 pinions are integral in rotation with the intermediate shaft 55, their axis coinciding with the axis of the intermediate shaft 55. When the bevel gears of this embodiment use simple conical teeth, the axis of the intermediate shaft 55 is located in a radial direction, according to the median which connects a piston 6 to the rotation shaft 15. The gear made between the intermediate shaft 55 and the first rolling body 16 or half pinion 53 is comparable to a gearbox with a bevel gear. It is the same for the gear made between the intermediate shaft 55 and the second rolling body 19 or conical wheel 54. The gear ratio introduced by this gear depends on the sizes selected for making the gearboxes with angle returns and he is, according to the invention, 2: 1. The conical half-pinion 53 and the upper conical pinion 56 meshes without reduction, they therefore have the same number of teeth and a straight single toothing inclined at 45 °. The lower bevel gear 57 and the bevel gear 54 mesh with a ratio reduction 2, the conical gear 54 therefore has a more open cone (about 127 ° vs. 53 °) with twice as many teeth as the lower bevel gear 57 The gear ratio remains positive if the teeth cones of the first rolling body 16 or bevel half-gear 53 and the second rolling body 19 or conical gear 54 point in opposite directions.

This embodiment variant has the advantage of being free of space constraints inside the diamond 4, because the distance between the two bevel gears 56, 57 of the intermediate shaft 55 is not related to the toothing and can therefore vary easily. More particularly in the case of machines of very large dimensions, this embodiment has the advantage of a simple transmission (without tension rollers), rigid but light thanks to hollow intermediate trees of large outside diameter, and finally, much less cumbersome than a machine whose transmission mechanism would include large gear wheels.

In an alternative embodiment not shown in the figures, it is possible to offset or tilt the axis of rotation of the intermediate shaft 55, taking complex conical teeth.

The transmission mechanism 14 illustrated in the accompanying figures is a reversibly operating mechanism which ensures reversible operation of the machine of the invention. The ratio of reduction of 2 between the first rolling body 16 and the second rolling body 19 allows the use of reversible mechanisms. Indeed, for all the embodiments and variants presented in this document, it is possible to size the rolling bodies 16 and 19, as well as the intermediate transmission members 18, with gear ratios, tooth angles, materials and games that make their operation reversible. Thus the entire transmission 14 is perfectly reversible.

The median arms 23,24 serve essentially to support the intermediate rolling bodies 21, or the tensioners 51, or the reference rollers not shown in the figures. When using intermediate rolling bodies 21, the arms The medians 23, 24 are also intended to protect the gears of the transmission mechanism 14 against the radial forces that engage the pistons 6. Indeed, by choosing an optimum game at their pivoting joints about the axes 29, 30, less than that of the pivoting joints 7, the middle arms 23,24 cash radial forces and allow the gears to function properly. In a variant not illustrated, it is possible to add to the gears and to the toothed sectors of the cylinders of revolution so that these cylinders lean against each other to prevent the teeth from being subjected to radial forces. However, the contact pressures generated between these cylinders (cylinder against cylinder) are greater than those generated by the median arms 23,24 (cylinder in bore).

FIGS. 5a and 5b illustrate a machine made according to a third variant, in which the first rolling body 16 is a toothed wheel integral with the piston 6, the second rolling body 19 is a toothed wheel integral with the rotation shaft 15 and the intermediate transmission member 18 is a chain 32 connecting the two rolling bodies 16, 19. The gear wheels have, in generally known manner, toothing suitable for driving by a chain. The transmission mechanism 14 of the machine thus uses four chains 32 connecting the four gears of the pistons 6 to a central gear integral with the rotation shaft 15. As in the previous variants, the machine uses two median arms 23,24 articulated pivotally mounted about end axes 29,30 each passing in the center of a piston 6, the central orifice 26 of each median arm 23,24 being traversed with clearance by the rotation shaft 15. The mechanism transmission 14 uses, in a known manner in chain transmissions, a system for tensioning the chain (not shown in the figures) which advantageously bears on the median arms 23,24. The operating clearance of said system being predefined according to the technical specifications of the application (transmitted torque, speed, link size, etc.).

The advantages of such a chain transmission mechanism 32 lie mainly in the fact that the use of the intermediate bearing bodies 21, 21 'can be dispensed with, which has the main advantage of obtaining a transmission mechanism according to the invention independent of the distance between the first and the second rolling body. This can make it easier to adapt to an imposed dimension of the machine. For short distances center distance, it is possible then to increase the diameter of the first and second rolling body and the pitch of the teeth (within the possibilities of integration of the first rolling body on a small piston). For long distances between centers, on the contrary, these diameters of the first and second rolling bodies will be limited compared with a variant that would exploit intermediate rolling bodies. This in particular makes it possible to produce a machine of large dimensions, rotating at a higher speed, while limiting the dynamic and mechanical effects due to the inertia and moments of inertia of the intermediate rolling bodies 21 rotating at high speed and irregularly by a combination of rotational movements.

FIGS. 6a and 6b illustrate a transmission mechanism 14 made according to a fourth variant of the first embodiment which differs from the third variant mentioned above (FIGS. 5a and 5b) in that two first opposite rolling bodies 16 (where a rolling body 16 is integral at its center of the center of a piston and the other of the center of the piston opposite) are connected together and are connected to the second rolling body 19 by a common chain 33. This solution has the advantage of being a simplified design, while allowing to transmit a greater torque between the pistons 6 and the rotation shaft 15 because the width of the chain can be doubled.

Figure 6c illustrates another alternative embodiment of the transmission mechanism 14 of the invention wherein all the first rolling bodies 16 are connected to the second rolling body 19 by a common belt 33 '. Tensioners 51 are provided for bringing the common belt 33 'into contact with the periphery of the second rolling body 19, in particular two tensioners 51 delimit the contact portion of the belt 33' with the body 19. The axes of the eight tensioners 51 that comprises the machine are supported, for example, by middle arms 23 and 24. This solution has the advantage of allowing the transmission of a torque even greater than in the embodiment of Figures 6a and 6b.

Figures 7a and 7b illustrate a transmission mechanism 14 made according to a fifth variant of the first embodiment which differs from the third variant mentioned above (FIGS 5a and 5b) in that the intermediate transmission member 18 is here a toothed belt 34. Thus, the first rolling body 16 is a toothed wheel integral with the piston 6, the second rolling body 19 is a toothed wheel integral with the rotation shaft 15, the movement between the two wheels being transmitted by a toothed belt 34. Such a toothed belt is made of a flexible material, for example fiber reinforced elastomer. The advantage of such a solution is that it is less noisy in operation than a chain, that the toothed belt is lighter than a chain, while having a more regular operation. Thus, it applies more particularly to fast and quiet machines, but operating at lower pressures, for example less than 30 bar where the flexibility introduced into operation by the toothed belt is not a problem. A toothed belt is a synchronous belt, it ensures a transmission without slip or phase shift between the inlet and the outlet.

FIGS. 8a and 8b illustrate a sixth variant embodiment of the transmission mechanism 14 of the invention in which the first rolling body 16 and the second rolling body 19 are pulleys connected by a smooth belt 35. A tensioning roller (not shown in the drawings) may be provided on the middle arms 23,24 to adjust the tension of the belt when it is of the adhesively-driven flat belt type. The advantage of such a solution is that the smooth belt 35 is easier to implement and that it can adjust more finely the angular positions between the first rolling body 16 and the second rolling body 19 during assembly because there are no notches to respect and therefore no shifting mechanism to implement. Furthermore, any slippage may occur during operation and result in desynchronization between the first rolling body 16 and the second rolling body 19. However, this drawback can be overcome by using a diamond guide device 4 formed by the articulated pistons, so that the sliding of the smooth belt 35 automatically resynchronizes the angles between the first rolling body 16 and the second rolling body 19.

In another variant, one could use a trapezoidal belt drive by wedging, so lower slip.

Figures 9a to 9c illustrate a transmission mechanism 14 made according to a seventh variant of the first embodiment. According to this variant, the first rolling body 16 and the second rolling body 19 are friction rollers, an intermediate rolling body 21 is also provided between the two rolling bodies 16 and 19. Apart from the transmission by friction and not by gear, the structure of the mechanism 14 according to this variant is quite similar to that described with reference to Figures 3a to 3d, the reference numbers having the same role have been partially reproduced in Figures 9a to 9c. The friction rollers have a metal core and are coated on the surface of a high-friction elastomer casing. To respect the gear ratio positive and equal to two, the diameter of the central roller 37 mounted fixed in rotation on the rotation shaft 15 is equal to twice the diameter of a half-roller 36 integral with a piston 6. A intermediate roller 38 is sized according to the size of the diamond 4. The transmission mechanism 14 produced according to this variant allows a drive by adhesion, which is subject to possible slippage, while being more rigid than a drive by smooth belt 35.

In a variant (not shown in the figures), it is possible to use profiled rollers or having spherical, cylindrical protuberances, etc., which allows a drive without sliding between the pistons and the rotation shaft.

FIGS. 10a to 10c illustrate an eighth variant embodiment of a transmission mechanism 14 in which the first rolling bodies 16 and the second rolling body 19 are friction rollers similar to those of FIGS. 9a to 9c, but in which the mechanism transmission 14 uses a plurality of intermediate bearing bodies 21. More particularly, a half-roller 36 is mounted integral with movement of a piston 6 and a central roller 37 is mounted integral with the rotation shaft 15 using a key 22. Three intermediate rollers 38 are held by each elongated part of a median arm 23, respectively 24. A median arm thus supports six intermediate rollers 38. The median arms have the same role as in the previous variants, so they are pivotally mounted in joints 29,30 in the center of the opposed pistons 6, the rotation shaft 15 passing with or without play in the center of each median arm. The ends 27,28 of the median arms 23,24 are pivotally arranged in the center of a piston 6, a median arm 23 connecting the midpoint of a piston 6 with the tangent to the rotation shaft 15, making the we obtain a spiral arrangement of the ends of the median arms from their center. This allows each end to support a plurality of intermediate rollers 38, tangentially offset by their support pins 31 ', 31 "and 31'". The advantage of such a solution is that the multiplication of the rollers makes it possible to reduce their diameter and therefore the inertia of the transmission and its harmful consequences. However, an odd number of intermediate rollers must be used in order to maintain a positive transmission ratio. The pebbles are not aligned on the median in this realization, which allows to adapt rollers of standard dimensions to a machine with dimensions imposed.

Figures 11a to 11d illustrate a transmission mechanism 14 according to a second embodiment of the invention. The transmission mechanism 14 comprises a first rolling body 16 which is a toothed sector comprising an axis 17 which is mounted fixed in rotation in the center of a piston 6, toothed sector which is brought to mesh with a ring gear 40 having an internal toothing which forms the second rolling body 19. The ring gear 40 has an axis of rotation which is coaxial with the central axis 43 of the machine which passes through the intersection of the median arms 23,24, the ring gear 40 forming the drive shaft 15 of the transmission. The median arms 23,24 are pivotally mounted at their ends on the pins 17 which pass through the pistons 6 and serve to support the radial forces acting on the pistons, the games in the pivoting joints of the median arms 23,24 being smaller than that of the spacing between a toothed sector 39 and the ring 40. The ring gear 40 has a cylindrical peripheral contour 41 and the toothed sectors 39 are arranged one in the extension of the other so that they form a deformable inner ring 42 of width (in the radial direction) greater than that of an outer chamber 8 of the machine. The deformable inner ring 42 is formed by articulating the toothed sectors 39 between them, each tooth sector 39 having at its ends a protrusion 44 and a recessed area 45, where each protuberance 44 is installed in a recessed area 45 adjacent toothed sector.

This solution has the advantage of being exempt from any pinion 48 or intermediate rolling body, which limits the play in the transmission, to avoid shock, nuisance and damage to parts leading to premature wear . In addition, the dimensions of the rolling bodies are greater, for more robustness of the transmission. Moreover, the internal toothing makes it possible to increase the number of teeth in contact (driving ratio), for a better transmission of the effort. It should also be noted that the choice of gear sizes is freer because it is almost independent of the dimensional parameters of the diamond.

The center of the diamond is free and empty of any mechanical element. Indeed, when the median arms 23,24 are not necessary to the machine, especially in the case a construction where the rotor parts are rigid with small clearances in the pivoting joints 7, this free space then forms a central cavity 52 with variable volume that can pump, compress, turbinate, move fluid. This cavity can also simply provide space for the passage of components or accessories from the environment of the machine. Indeed, access to the interior of the diamond 4 of such machines is here improved, which facilitates maintenance or repair operations. In a variant not shown in the figures, the inner cavity 52 could be further divided into a plurality of variable volume chambers, for example using sealed internal walls.

In an alternative embodiment (not shown in the figures), but using a gear transmission mechanism of the type shown in FIGS. 2 to 4 and friction rollers of the type shown in FIGS. 9 and 10, the components of the transmission mechanism 14 can dividing the space of the internal cavity 10, especially insofar as the intermediate transmission members 18 used in the transmission mechanism 14 oppose a sufficient brake to the passage of the fluid from one internal cavity 10 to the other. This can be explained with reference to FIG. 2 where the internal cavity 10 can be divided by the components of the transmission mechanism 14 of each median arm into four variable volume cavities 10a, 10b, 10c and 10d. In such an alternative embodiment, the axial clearances between the rolling bodies 16 and 19, the intermediate transmission members 18 and the side walls or the median arms 23, 24 must be minimal in order to ensure a tightness of the fluid present in each cavities 10a to 10d. The fluid can arrive in one of the cavities 10a to 10d from a fluid circuit external to the machine via intake and discharge ports made in the lateral flanges of closure of the machine. Preferably, in order to make the cavities 10a to 10d even more tight, the use of the median arms 23,24, shoulders on the gables, non-overlap area of the flexible envelopes of the friction rollers are to be avoided. Indeed, if the optional median arms 23 and 24 are omitted, the gear transmission (FIG. 2) is very close to the production conditions (tolerances, clearances, materials, manufacture) of gear pumps that are well known to the machine. skilled in the art, because the cavities are delimited by the contact areas in the gear teeth, the circular walls tangent to the tops of the teeth and the flat surfaces of the pinions which are fitted against the lateral closing walls of the machine. Likewise, the structure of a friction roller transmission mechanism (FIGS. 9a and 10a) is close to that of a lobe pump using lobe wheels without external synchronization, because the contact between the lobe wheels is with a slight elastic deformation of the elastomeric casing which covers the lobe wheels in order to improve the sealing and the transmission of the torque. The separations thus created by the transmission mechanism of the invention serve to form more cavities for pumping, compressing, turbining, or moving one or more fluids, but also to amplify volume variations, or to limit dead volumes.

The closed spaces forming cavities with variable volume can also be obtained by using other surfaces, such as the space included (FIGS. 11a and 11b, as described below) between toothed sectors 39, the crown toothed 40, the stator 2 and a sidewall reported.

An example of advantageous dimensioning of such a transmission mechanism 14 according to this second embodiment is described in the following. The machine comprising a transmission mechanism according to FIGS. 11a to 11d is made from a ring gear 40 with internal teeth of module 3 with 80 teeth, and having four toothed sectors 39 of module 2 which would have 40 teeth if they were integers. The dimensions of the machine are about 50 mm for the height of the pistons 6, a total height of the closed machine of about 100 mm and about 20 mm of tooth width. The distance between the tops of the two opposed pistons 6 is 100 mm and the diameter of the machine is about 200 mm. The contact of internal teeth on external teeth offers a ratio of driving (one understands the number of teeth in contact) much more important, which improves considerably the service life of the machine as well as the transmittable torque.

The space released by the suppression of the planet gears 48 makes it possible to increase the pitch diameters and therefore the efficiencies of the meshing systems. In addition, for the same reasons of space saving, it is possible to adopt larger modules with more robust feet of teeth which significantly increases the transmittable torque.

It is possible to transmit a torque of 100 Nm with alloys of the type 11 SMnPb30 steel 11 used for standard gears.

The suppression of the planet gears 48 makes it possible to gain a conversion of movement. The estimated efficiency for the transmission mechanism in this case is of the order of 98%. FIGS. 12a to 12c illustrate an example of application of a MRLD comprising a transmission mechanism according to the invention, the machine being a fast-acting domestic air compressor 50.

The pistons 6 comprise half-gears 47 which are the blocks made by electroerosion and plugged into a lightening groove 46 made along the intrados face 11 of each piston 6. The half-gears 47 meshing with a gear wheel 49 fixed on the rotation shaft 15 by means of planet gears 48. The planet gears 48 are pressed together on a standard pin on the middle arms 23,24. The planet gears 48 are guided up and down by the median arms 23,24. The rotation shaft 15 is a piece of simple revolution connected to the toothed wheel 49 thanks in particular to a key 22. The rotation shaft 15 has along its length grooves or circular grooves for receiving elastic fixing rings (of the circlip type, not visible in the figures) blocking in axial translation the toothed wheel 49 and blocking the axial translation of the shaft relative to the middle arms 23,24 and thus relative to the stator 2. In operation, the rotation motor torque of the rotation shaft 15 is transmitted to the pistons 6.

The dimensional and operating parameters of the various components of the machine have been designed to be able to transmit the desired torque, while presenting a silent operation, avoiding generating vibrations and being able to be realized at a reduced cost. Thus, in operation, the compressor 50 reaches the discharge pressure of 3 bar absolute, for admission to atmospheric pressure with a flow rate of 1500 normal L / min at 3000 rpm, for a torque of 20 N. m.

Thus, the reduction is done on the same floor to simplify the design of the machine and reduce the cost, respecting the gear ratio between the half-pinions 47 secured to the piston 6 and the toothed wheel 49 integral with the shaft. rotation 15, which must be positive and of ratio 2: 1. Straight spur gears are preferably used for their good performance, standardization, absence of axial forces and it is preferred to choose identical module toothings for all the pistons in order to simplify the design. Furthermore, the same pitch diameter of the planet gears 48 is advantageously chosen as the pitch diameter of the piston half-gears 47 in order to reduce the wear of the gears. The diameters of the gears and their modules have been chosen by sizing them as much as possible to optimize the efficiency, the wear and the torque transferable. The planet gears 48 are mounted between the half-pinion 47 of the piston 6 and the toothed wheel 49 of the rotation shaft 15 so as not to hinder the crushing of the diamond 4 and keep a maximum of displacement.

The spacing in the gears (between each pair of gears) is between the nominal dimension and the dimension to which is added a clearance of 0.05 mm. These dimensions are maintained in operation because the radial forces are resumed with the median arms 23,24, to prevent stray forces from damaging the gears. Such a gear transmission mechanism is adapted to accurately, uniformly and efficiently transmit a relatively weak torque.

Considering the above considerations, the gears were designed according to the dimensional parameters of the machine, especially for a piston height which is 50 mm, the total height of the closed machine being about 100 mm, the side the diamond is 100 mm and the diameter of the machine is about 200 mm.

For example, a module equal to 1 is chosen, which ensures a reasonable number of teeth (for example greater than 17), which favors the efficiency of the transmission (which is about 0.96), as well as the mechanical strength of the transmission. The tooth width that optimizes the available space in the machine is maximum 17 mm, and it is desirable to choose this maximum.

The materials that can be used to make the gears are for example a hardened steel type 12NC15 or 11 steel SMnPb30, commonly used to make gears. As regards the half-pinions 47 secured to the pistons 6, however, stronger materials are preferred, especially a type of steel 42CD4 or 37D8. It is inadvisable to open a pinion to make it a toothed sector, as this would cause the deformation of the pinion. For reasons of resistance to the stresses of the half sprockets 47, it is preferred to make them by a method of cutting by electroerosion in blocks of isotropic material. Furthermore, the small bearing surfaces at their teeth, may eventually result in a matting half-pinions attached to the pistons and, therefore, introduce games that interfere with the transmission. To avoid this problem, it is conceivable to arrange flat bearing surfaces on each side of the toothed sector. The profile of the teeth is symmetrical so that this piece can be mounted indistinctly in both directions. With these considerations and according to a sizing given by way of example above, the calculations have estimated a transmission lifetime of approximately 500 Ohms and a transmission efficiency of the order of 0.96 with few heating of the components during operation.

In a simplified adaptation of the invention, not shown in the figures, the transmission mechanism according to the invention can also operate with a single first rolling body mounted on a single piston, or with only two or three first rolling bodies mounted. on respectively two or three pistons. This simplified version can be applied to the variants illustrated in FIGS. 3a to 3d, 4a to 4b, 5a to 5b, 7a to 7b, 8a to 8b, 9a to 9c, 10a to 10c and 11a to 11d. While presenting disadvantages in terms of balancing the masses within the transmission mechanism or in terms of guiding the rotor, such a constructive simplification nevertheless has an economic interest, by making it possible to reduce the cost of producing the transmission mechanism.

Other variants and embodiments of the invention may be envisaged without departing from the scope of the invention as delimited in the claims.

Claims

1. Rotatable deformable diamond machine comprising a) a rotor (3) which is a deformable rhombus (4) in contact, with or without play, with the inner surface of an enclosure (1) forming a stator (2) and / or with the outer surface of a central ring, said deformable rhombus (4) comprising four pistons (6) connected, one after the other, by a pivoting joint (7) of axis parallel to the longitudinal axis of the enclosure (1) and thus forming a closed chain; and b) a transmission mechanism (14) for movement between the pistons (6) and a rotation shaft (15) coaxial with the central axis of the machine, said machine being characterized in that said transmission mechanism (14) ) comprises: - a first rolling body (16) fixedly mounted on at least one piston (6), preferably on each piston (6), the axis (17) of said first rolling body (16) passing centrally piston (6) and connected to a second rolling body (19) whose center passes through the central axis of the machine and is integral with said rotation shaft (15), - the first rolling body (16) being connected at the second rolling body

(19) directly or by an intermediate transmission member (18) - and that the gear ratio between the first (16) and the second rolling body (19) is equal to 2 and is positive.

2. Machine according to claim 1, characterized in that said first rolling body (16) and said second rolling body (19) are provided with driving protuberances on at least a part of their periphery to perform a drive by obstacle .

3. Machine according to one of claims 1 or 2, characterized in that said transmission mechanism (14) comprises gears with parallel axes and straight teeth.

4. Machine according to one of claims 1 or 2, characterized in that said transmission mechanism (14) comprises gears with parallel axes and helical teeth.

5. Machine according to one of the preceding claims, characterized in that the first rolling body (16) is a half-pinion integral with a piston (6) which meshes with a toothed wheel forming the second rolling body. (19) integral with the central shaft (15) of the machine by means of an intermediate rolling body (21) forming a satellite gear.

6. Machine according to one of claims 1 or 2, characterized in that said first rolling body (16) is a bevel half-pinion (53) connected to said second rolling body (19) which is a conical gear ( 54) by an intermediate shaft (55) provided with bevel gears (56, 57) at the ends.

7. Machine according to one of claims 1 to 4, characterized in that said first rolling body (16) is a toothed circular sector (39) connected to a piston (6) which meshes directly with a ring gear ( 40) device with internal teeth secured to the rotation shaft (15) of the machine.

8. Machine according to claim 7, characterized in that the ring gear (40) has a circular peripheral contour (41) and that the toothed sectors

(39) are arranged one in the extension of the other so that they form an inner ring (42) deformable in width (in the radial direction) greater than that of an outer chamber (8) of the machine.

9. Machine according to one of claims 7 or 8, characterized in that it comprises an internal cavity (10) to the diamond having at least one variable volume cavity for pumping, turbinating fluid or to receive an external element to the machine.

10. Machine according to one of claims 1 or 2, characterized in that said first rolling body (16) and said second rolling body (19) are connected by a chain (32,33,33 ') or by a timing belt (34,33,33 ').

11. Machine according to claim 1, characterized in that said first rolling body (16) is connected to said second rolling body (19) by a smooth belt (35).

12. Machine according to one of claims 10 or 11, characterized in that two first rolling bodies (16) opposite are connected to the second rolling body (19) by a common chain (33) or a common belt or that all the first rolling bodies (16) are connected to the second rolling body (19) by a common belt (33 ') or a common chain.

13. Machine according to claim 1, characterized in that said first rolling body (16) and said second rolling body (19) are friction rollers (36,37) may each comprise a hard core covered with an envelope flexible.

14. Machine according to one of claims 1 to 4 or 13, characterized in that said first rolling body (16) is connected by at least one intermediate rolling body (21) to said second rolling body (19).

15. Machine according to one of the preceding claims, characterized in that two pistons (6) opposite are connected together by at least one median arm (23,24), each end (27,28) of said median arm being pivotally mounted in the center of each piston (6).

16. Machine according to one of the preceding claims, characterized in that the transmission mechanism (14) has a reversible operation.

17. Machine according to one of the preceding claims, characterized in that the piston (6) and said first rolling body (16) form a single piece.

18. Machine according to one of claims 1 to 5 and 13 to 17, characterized in that the transmission mechanism (14) separates the internal cavity (10) of the machine into one or more cavities with variable volume (10a , 10b, 10c, 10d).