FR2464389A2 - Variable flow hydraulic motor or pump - has retractable vanes on rotor to vary hydraulic fluid flow path - Google Patents

Abstract

In each hydraulic flow path a number of reaction plates (5) are fixed to the stator (1) and a number of retractable blades mounted on the rotor (2). The blades are retracted as they pass the reaction plate to introduce fluids under pressure downstream of the reaction plates and to allow the fluid to exhaust upstream of the reaction plates. The hydraulic fluid path is bounded by a fixed ring on the stator (1) and a movable ring (3) on the rotor so that the width of the flow path can be varied.

Description

"EYDRAULIC MACHINE WITH VARIABLE CYLINDER AND IMPROVABLE PARTITION PARTITIONS"
The present addition relates to a hydraulic machine with variable displacement and improved retractable partitions usable as a pump or as a motor.

 We already know different types of hydraulic machines with variable displacement and retractable partitions. These machines comprise at least one circular hydraulic vein of constant cross section delimited by cylindrical surfaces or flat surfaces normal to the axis of a rotor and a cylindrical stator. The vein is interrupted on the one hand by retractable partitions mounted on the rotor and on the other hand by reaction members mounted on the stator. When the rotor turns, the retractable partitions are erased in turn arriving at the level of the fixed reaction members. If the machines operate in "engine" version, a fluid under pressure is introduced into the hydraulic stream, downstream of the members reaction associated with the stator, and the pressure exerted on the retractable partitions of the rotor causes the rotation of the latter. Iwans the main patent application filed on December 13, 1977 under the number 77 38 914, the variation of the displacement is obtained by means of adjustments which make it possible to vary the width of the vein measured parallel to the axis of the machine.

In general, variable displacement hydraulic machines have the following disadvantages
- Given their complexity, these machines have a high manufacturing cost and a large size.

 - Some parts are subjected to high pressures without being hydraulically balanced, so that parasitic friction forces appear, while the pressure forces can cause deformation of the less rigid parts under certain conditions of overpressure, in particular at start-up.

 - To reduce friction, relatively large clearances must be provided, to the detriment of sealing.

 A hydraulic machine according to the addition comprises at least one hydraulic vein and, in each vein, on the one hand at least one reaction member secured to the stator of the machine and on the other hand retractable partitions secured to the rotor of the machine, means being provided for erasing the retractable partitions as and when they come before a reaction member, for introducing a pressurized fluid into the vein downstream of these reaction members, and for letting the fluid come out of the vein upstream of these same members, adjustment means making it possible to vary the width of the vein measured parallel to the axis of the machine, and it is characterized in that the hydraulic vein is delimited in the direction of the width between d on the one hand a fixed surface of the stator and on the other hand the surface of an axially movable counter-ring, this counter-ring rotating with the rotor and comprising recesses inside which the retractable partitions ables, arranged radially with respect to the axis of the machine, can move.

 According to an additional feature of the addition, the front and rear ends of the reaction members abut, respectively, against a shoulder provided externally on the counter ring and against an external shoulder of a ring fixed on the rear part of the counter Ring.

 According to an additional feature of the addition, the ring fixed to the rear part of the counter-ring comprises at least one inner lip which slides around a cylindrical surface of the rotor, two annular pressure chambers being thus delimited between the rotor and said ring to constitute a double-acting hydraulic cylinder capable of controlling the axial displacements of the counter-ring and of the ring.

 According to an additional feature of the addition, a channel extends parallel to the axis of the engine in each reaction member, to ensure the axial balancing of said member.

 According to an additional feature of the addition, the groove containing each reaction member in the stator is put under fixed pressure, at least one radial channel being provided through each reaction member to ensure the hydraulic balancing of said reaction member in the radial direction, by opening inside said groove under fixed pressure, said fixed pressure being able to take any value from atmospheric pressure.

 According to an additional characteristic of the addition, the front part of the counter ring is housed in a first circular groove of the rotor, contiguous to a second circular groove of larger dimensions in which the outer shoulder of the counter ring slides. , the two annular chambers thus delimited in the rotor being placed in communication, respectively, with chambers of equivalent cross-sections delimited in the stator by the rear part of the ring and by a shoulder of the ring, by means of axial passages hollowed out in the counter-ring and in the ring, this to ensure the hydraulic balancing of the counter-ring and the ring in the axial direction.

 According to a variant of the addition, the front part of the counter ring is integral with a series of pistons mounted to slide darts of the bores of the gold rot, each interval delimited between two retractable partitions being thus provided with a piston, the chamber pressure delimited at the front of each piston being placed in communication with the annular chamber delimited in the stator by the rear part of the ring by means of axial passages hollowed out in the counter-ring, in the ring, and in the corresponding piston, while the cross section of this annular chamber is equivalent to the ring of the cross sections of the pistons, this to ensure the hydraulic balance of the counter ring and the ring in the axial direction.

 According to an additional feature of the addition, the counter-ring has at least one radial passage ensuring communication between the vein and an annular hydraulic balancing chamber which is delimited between an external cylindrical surface of the rotor, an internal cylindrical surface of the counter-ring, a shoulder of the counter-ring, and an annular counter-piece adjacent to the edge of the retractable partitions, this annular chamber has the same width as the vein, whatever the axial position of the counter-ring, -to ensure the 'radial balancing of the latter when the chamber delimited between the rotor and the shoulder of the counter-ring is not pressurized by a channel connecting it to the hydraulic stream.

 This annular balancing chamber, on the other hand, has a constant width given by a groove formed in the rotor when the chamber delimited between the rotor and the shoulder of the counter-ring is connected to the vein by a channel formed through 11 shoulder of the counter ring.

 According to an additional feature of the addition, the watertightness of the vein is ensured, on the stator side, by a ring which is integral with the stator, the front face of which is adjacent to the edge of the retractable partitions, and the internal cylindrical surface is adjacent to a complementary surface provided on the front part of the reaction members and in the gap between two reaction members at the cylindrical surface of a shoulder belonging to the stator, the latter being notched to allow the reaction organs.

 According to an additional characteristic of the addition, provision is made, in the stator, immediately behind the ring ensuring the tightness of the vein, and opposite the face of each reaction member located opposite the axis. of the machine, a clearance connected to a fluid return pipe, these clearances allowing the reaction members to be pressed slightly against the stator.

 According to an additional characteristic of the addition, the watertightness of the vein is ensured, on the side of the counter-ring, by a ring with notches which is integral with the rotor and which remains adjacent to the edge of the retractable partitions whatever the position. axial of the counter ring. most, this ring with slots participates with the partitions to angularly connect the counter-ring and the rotor.

 According to a variant of the addition, the sealing of the vein is ensured, on the side of the counter ring, by a cylindrical hoop fixed in translation which remains adjacent to the edge of the retractable partitions whatever the axial position of the counter ring.

 According to an additional characteristic of the addition, fluid return pipes are provided in the rotor which open at the ends situated on the side of the axis of the machine, radial grooves of the rotor and the counter ring, these pipes ensuring the drainage of leaks at the level of said radial grooves.

 According to an additional characteristic of the addition, each reaction member has substantially the shape of a key, and pos sèae a ring sector profile over its entire length or only at the end at one or both of its ends .

 According to a variant of the addition, each reaction member has a cylindrical shape, and is entirely contained in the stator.

 According to another variant of the addition, each reaction member has a cylindrical shape, and is mounted between leather and flesh, that is to say only partially in the stator.

 According to an additional feature of the addition, the machine comprises two half-rotors and two counter-rings arranged in identical ways on either side of the retractable partitions placed in the central part of the machine.

 According to an additional feature of the addition, the veins are arranged in pairs, each couple comprising two concentric veins which are associated with the same counter-ring.

 The appended drawing, given by way of nonlimiting example, will allow a better understanding of the characteristics of the addition.

 - Figure 1 is a partial schematic view of a machine according to the addition, in section along a plane passing through the axis.

 - Figure 2 is a section Il-Il (fig 1).

 - Figures 3 to 5 are partial views of a hydraulic machine according to the addition, in section along a plane passing through the axis, and in positions of maximum displacement, intermediate displacement, and zero displacement, respectively.

 - Figure 6 is a partial view on an enlarged scale, and in axial section, of a hydraulic machine with a practical embodiment of the displacement control.

 - Figure 7 is a section VII-VII (fi 3).

 - Figure 8 is a perspective view in partial section of the rotor of this machine.

 - Figure 9 is an exploded perspective view showing the counter ring, the ring, and a form of organ ie reaction of this machine.

 - Figure 10 is a perspective view of the ring with slots ensuring the tightness of the vein on the side against the ring.

 - Figures 11 and 12 are views similar to Figure 3, according to variants.

 - Fifre 13 is a partial section XIII-XIII (fig 12).

 - Figures 14 to 18 are views similar to Figure 3, according to other variants of the addition.

 - Figure 19 is a section ZIX-XIX (fig 18).

 - Figure 20 is a view similar to Figure 3, according to another variant of the addition.

 - Figure 21 is a section XXI-XXI (fig 20).

 - Figures 22 to 25 are similar to Figure 3, according to other variants.

 - Figure 26 is a section XXVI-XXVI (fig 25).

 - Figures 27, 28 and 29 are views similar to Figure 3, according to other variants of the addition.

There is shown schematically in Figure 1 a hydraulic machine according to the addition. This machine mainly includes
- Fixed Unstator 1.

 - A rotor 2.

 - Two counter rings 3.

 - A series of retractable partitions 4, for example 24 single retractable partitions, or 12 double retractable partitions, therefore symmetrical.

 - Six reaction organs 5.

 - A central spacer 6.

 In FIG. 3, which shows a practical embodiment of the machine, it can be seen that in fact the stator 1 comprises two half-stators 1a and 1b connected to each other by the spacer 6.

 On each side, the rotor 2 has two circular grooves 7 and 8 (see FIG. 8) inside which respectively slide the front part of the counter-ring 3 and an external shoulder 9 of this counter-ring. the rotor 2 and the counter-ring 3 have respective radial grooves 10 and 11 (see FIGS. 8 and 9) inside which the partitions 4 are mounted to slide. These partitions 4 have two lateral fingers 12 which give them a "T" profile.

Each finger 12 plays the role of a follower roller vis-à-vis a return cam 13 provided on the corresponding half-stator. Each partition 4 further comprises an external boss 14 which slides on a cam 15 integral with the spacer 6, this cam 15 giving the partitions 4 their active position.

 At its rear end, each counter-ring 3 is integral with a ring 16 provided with an external shoulder 17, and the two ends of each reaction member 9 (see FIG. 9) bear, respectively, on the external shoulders 9 and 17 of the counter-ring and of the ring 16. The axial positioning of each reaction member 5 is thus carried out precisely, the operating clearances being very small. Each reaction member also has its rear part engaged inside an axial groove of the corresponding half-stator, and is therefore immobilized in rotation relative to the axis of the machine.

The following channels are provided in order to ensure hydraulic balancing of the parts
- Each reaction member 5 has at least one longitudinal channel 18 which passes right through it, and at least one radial channel 19 opening into the corresponding half-stator, on a chamber 20 pressurized or connected to atmospheric pressure by through pipelines 21.

 - Axial channels 22 are provided in the shoulders 9.

 - Axial channels 23 are provided in the shoulders 17.

 - Axial channels 24 are provided in the counter-ring 3 and in the ring 16.

 - Radial channels 25 are provided in the counter-ring 3, slightly behind the shoulder 9.

This hydraulic machine has two circular hydraulic veins 26. Each vein 26 is delimited
- at the front, by the rear flat face of a shoulder 9;
- at the rear, by the flat front face of the corresponding half-stator
- outside, by the inner cylindrical surface of the rotor 2 which also delimits one of the circular grooves 8;
- inside, by the external cylindrical surface of the counter ring 3.

 Each vein is divided into several compartments on the one hand by the partitions 4 and on the other hand by the reaction members 5. In known manner, the partitions 4 are provided with notches 27 allowing the reaction members 5 to pass for the rotation of the rotor.

 the basins 28, arranged in each interval between the partitions 4, are delimited by the internal cylindrical surface of the counter-ring 3, by an internal recess 29 in the external cylindrical surface of the rotor 2 and by an annular counter-piece 30 adjacent to the edge of the retractable partitions 4. The width of each basin 28 is the same as the width of the corresponding groove 8 of the rotor, whatever the axial position of the counter-ring 3, this to balance the pressures prevailing in the vein 26 and in the chamber 37 and, consequently, on the external surface of the shoulder of the counter-ring 3.

 The watertightness of the stream 26 is finally ensured by means of the outer ring 31 and an inner ring with slots 32. The outer ring 31 is integral with the corresponding half-stator, its front face is adjacent to the edge of the retractable partitions 4 , and its internal cylindrical surface is adjacent to a complementary surface 33 (see FIG. 9) provided on the front part of the reaction members 5 and to a cylindrical surface belonging to the corresponding half-stator. The internal ring with slots 32 is integral with the rotor 2, and it remains adjacent to the edge of the retractable partitions 4 regardless of the axial position of the counter-ring 3.

 Each half-stator also has a circular groove 34 inside which the outer shoulder 17 of the corresponding ring 16 is mounted to slide, and a smaller circular groove 35 inside which is mounted to slide the rear part of the ring 16. The cross section of the chamber 36 delimited in the groove 34 by the shoulder 17 is equal to the cross section of the chamber 37 that the shoulder 9 of the counter ring 3 delimits in groove 8 of the rotor. the same, the chamber 38 which delimits the rear part of the ring 16 in the groove 35 has the same cross section as the chamber 39 delimited in the groove 7 of the rotor 2 by the front part of the counter ring 3.

 Each ring i6 is provided with an inner lip 40 which slides around a cylindrical surface of the rotor 2, delimiting between this ring 16 and the rotor 2 two annular pressure chambers 41 and 42, the whole functioning in the manner of a double-acting hydraulic actuator for controlling the axial displacements of the counter-ring 3 and of the corresponding ring. The hydraulic supply of the pressure chambers 41 and 42 is carried out by means of internal channels 43 and 44 of the rotor 2, and by means of a rotary joint 63 disposed at one of the ends of the shaft 2 .

The operation is as follows
The hydraulic machine being, in this case, used as a motor, the half-rotors are connected to a supply line for pressurized fluid 46 which opens into the stream 26 in three locations, downstream of the reaction members 5 taking into account the direction of rotation of the rotor indicated by arrow 47 (figure 7). An exhaust pipe 48 opens into the stream 26 at three locations, upstream of said reaction members 5, in the same way. The profile of the cams 13 and 15 is chosen so as to allow correct erasure of the retractable partitions 4 at the level of each reaction member 5, that is to say so as to allow the passage of the members 5 in the notches 27 of the partitions 4.

 To control the variation in displacement of the machine, pressure is sent either to the annular chambers 41, to reduce the displacement, or to the annular chambers 42, to increase the displacement, the displacement being proportional to the width of the vein 26 associated with each half-rotor. The annular chambers 41 and 42 are supplied in pairs via the same pipes, and a conventional servo-control system, not shown, makes it possible to obtain the position of the counter-rings to give the desired cubic capacity.

 FIG. 4 shows an intermediate displacement position, but there are an infinite number of possible intermediate positions between the maximum displacement position illustrated in FIG. 3 and the zero displacement position illustrated in FIG. 5.

It can be seen that the particular shape of the counter-rings 3, which constitutes one of the advantageous novelties of the addition, makes it possible to perform the following various functions:
- Positioning of the reaction members 5 in the axial direction.

 - Hydraulic balancing of the reaction member 5.

 - Hydraulic balancing of the counter-rings 3 and the rings 16, in order to limit the operating forces and the deformations of the parts.

 - Realization of a tight seal between the vein 26 associated with each counter-ring 3 and the reaction members 5.

 The hydraulic balancing of the reaction members 5 is carried out, in the axial direction, via the channels 18 which bring to the level of the rear face of the reaction members 5 a pressure equal to the pressure prevailing in the vein 26 at center of the reaction member 5. In the radial direction, the hydraulic balancing of said members 5 is carried out by means of the channels 19, by bringing the chambers 20 to low pressure. This may for example be atmospheric pressure, or drainage pressure.

 The channels 22 and 23 of the shoulders 9 and 17 make it possible to bring the pressure of the vein 26 into the chambers 36 and 37, this with the double aim of limiting the deformations of the parts at the level of said shoulders 9 and 17, and of compensating for axial balancing part of moving parts 3 and 16.

 The channels 24 make it possible to obtain total axial balancing of the movable assembly comprising the counter-ring 3 and the ring 16. A pipe 43 of the rotor 2 makes it possible to bring about a booster or drainage pressure in the chambers 38 and 39. This pressure, routed through the channels 24 on the one hand on the front surfaces 44 and 45 of the counter ring 3 and on the other hand on the rear surface 65 of the ring 16, ensures this balancing.

 The radial balancing of the counter-basue 3 is ensured by means of the channels 25 which conduct the pressure of the vein 26 as far as the annular channel 28.

 The reaction members 5 must be tightly adjusted in the stator. For that, it is necessary that the surface of the bottom of the groove is complementary to the external surface of reaction member, that is to say that the surface of the bottom of the groove must be a portion of cylinder, since reaction member is in ring section.

 This form of groove is very difficult to achieve. To avoid this, the outer ring 31 is provided, which is adjusted in the stator, in a shoulder of the latter, and whose inner surface corresponds to the outer surface of the reaction member, that is to say tell the outside diameter of the vein. The watertightness of the vein is therefore ensured both by the shoulder provided on the stator and by the cylindrical ring adjusting on the reaction member and on the preceding shoulder. It follows that the groove made in the stator to accommodate the reaction member is of rectangular cross section, in the manner of a keyway, The reaction member may have the shape of a ring over its entire length, or only on its front part, it being understood that its inner face is always complementary to the outer face of the cowling ring of the roter.

 Sealing at the level of the reaction members is also ensured by the internal ring with slots 32 of the side of the counter-ring 3, said ring 32 closing the grooves i1 necessary for the passage of the retractable partitions 4, when the machine is not in the maximum displacement position.

 As a variant, the use of the outer ring 31, mounted at the front of the stator and tangent to the outer face of the front part of the member which has a section in the form of a ring sector, makes it possible to produce the rear part of the cylinder-shaped member entirely contained in the stator or between leather and flesh and having an interior surface complementary to the exterior surface of the counter ring, as shown in FIGS. 11 to 14.

 According to FIG. 11, the reaction member 48 is entirely contained by the corresponding half-stator, and is of cylindrical shape in its adjusted part in the stator, its section being different at one of its ends which comes to adjust in the vein.

 According to FIGS. 12 and 13, the reaction member 49 is still cylindrical in shape, but is mounted between leather and flesh, the axial balancing being obtained by means of a chamber 50.

 FIG. 14 shows the same layout of the reaction member 51 as in the case of FIG. 12, but with a simultaneous housing of this member in the set of parts 3 and i6.

 It is noted that, in the case of FIGS. 11, 12 and 13, the information of the axial position of the reaction members is taken directly.

 According to another variant illustrated in FIG. 15, the reaction member 5 can be radially balanced by having chambers 66 of equal or different sections on its external part and on its internal part, which may or may not be connected by a radial channel 67 to obtain either a total balancing or a support under low force of the reaction member on the stator, so as to maintain a constant clearance between the reaction member, fixed in rotation, and the counter-ring of the rotor, rotating.

 To obtain these chambers, there must be a seal between the rear part of the member and the stator, when the member 5 is axially balanced. This will be achieved either by adjusting the shape of the reaction member in the shape of the groove, or, which is easier to achieve, by using a reaction member whose section is a ring sector and a rectangular groove in the stator such as a keyway (see FIG. 2), provided that a cylindrical ring (see FIG. 6) is attached to the rear of the stator on a shoulder of the stator whose internal surface is complementary to the external surface of the reaction.

 Here we find the same arrangement as in Figures 11 to 14, but at the rear of the stator.

 It is quite obvious that to obtain a support under low load of the organ in the stator, one can be satisfied to carry out between this and the stator a sealed chamber according to the preceding provisions, and to connect it to the drainage or return circuit of the machine, the lower surface of the organ naturally putting pressure on the two ends of the organ.

 According to FIG. 16, it may be advantageous to axially balance the counter-ring and its ring in order to reduce the operating forces during the displacement, and to reduce the section of the parts which are then no longer subjected to stresses. bending, but only at compression forces.

 The front part of the counter ring 3 is housed in a first circular groove 68 of the rotor and the shoulder of the counter ring, which delimits the vein, is housed in a second groove 69 contiguous to the first, which thus delimits two annular chambers interrupted by the partitions which cross the counter ring.

 On the other side of this counter-ring, on the ring 16, the same arrangement has been made so as to also form two annular chambers there.

The axial balancing of the counter ring is carried out as follows
- The front surface 70 of the shoulder of the counter-ring, constituted by a succession of sectors delimited by the partitions, balances the rear surface 71 of this shoulder which is also the front surface of the hydraulic stream, and which is made up of also by sectors delimited by the partitions, by the intermediary of the channels 72 arranged in each sector of the shoulder and drilled through the latter or arranged at its periphery.

 The rear surface 73 of the shoulder, disposed on the ring behind the counter ring, balances the front face 74 of this shoulder by means of at least one channel 75. The front surface 76 of the counter-ring, increased by the surfaces 77 of the bottoms of grooves for passage of the partitions in the counter-ring, are equivalent to the rear surface 78 of the ring fixed to the counter-ring.

 These three surfaces 76, 77, 78 can be put at the same pressure, whatever the value of this pressure.

However, this device can be used as follows
The surface 70 and the surface 71 are balanced by the same pressure (P1), the surface 73 and the surface 74 are balanced by a pressure (P2), while the surfaces 76, 77 and 78 are connected to the meadow circuit, because the surface 77 may correspond to an internal shoulder of the counter-ring, and the application of high pressure on the surfaces would require unnecessarily increasing the thicknesses of the stator, the rotor, and the like, in order to resist the high forces generated by these pressures.

It will be noted that the surfaces 70 and 71 of each sector of the hoop are balanced by the pressures (P1) prevailing in the vein between two partitions at the location considered, this pressure being variable throughout a revolution. The pressure prevailing on the surfaces 73 and 74 of the shoulder of the ring is equal to the pressure (P2) taken in the middle of the reaction member, by the axial channel passing through it, and remains constant for operating conditions. fixed. This pressure (P2) will be little different from 2 if EP is the inlet pressure in
2 the engine and BP the outlet pressure. In other words, the pressures prevailing on surfaces 70 and 71 on the one hand, either (Pi) and on surfaces 74 and 73 on the other hand, or (p2) will not be the same as when the surface 71 of the sector in question of the shoulder of the counter-ring 3 passes in line with the axial hole of the reaction member.

 For the same reasons as above, it may be advantageous to radially balance the counter-ring 3 and its ring 16. If the counter-ring is axially balanced, it is necessary to have, between the rotor and the counter-ring, two chambers 79 and 80 (fig 17). The chamber 80, which is circular, is disposed under the ring 16, and its width 81 is equal to the width of the groove produced in the stator where the shoulder of the ring 16 moves. The chamber 79, which is disposed between the partitions, may have the form of hollows If the travel of the partitions is such that in the high position it no longer divides into sectors the surface of the rotor considered, and its width 82 is equal to the width of the groove formed in the rotor where moves the shoulder before the counter-ring (i.e. from the groove in which the vein is delimited).

Radial channels 83 connect the chambers thus formed to the opposite working chambers
According to another variant illustrated in FIGS. 18 and 19, there is provided in the stator, immediately behind the ring 31, and facing the external face of each reaction member 5, a clearance 52 connected to a pipe 53 return or fluid drainage. These clearances allow the reaction members 5 to be pressed slightly against the stator. The rear outer part of the reaction members is adjacent to the cylindrical surface 84 of the stator. It is also possible to arrange in the rotor fluid return pipes 54 which open at the ends situated on the side of the axis of the machine, radial grooves 10 and 11 belonging respectively to the rotor 2 and to the counter-ring 3. These return pipes make it possible to limit the path of the leaks occurring at the level of said radial grooves, by draining these leaks. The counter-ring 3 and the ring 16 are balanced by channels 54 bringing the drainage pressure in the chambers 38, in the chambers 39, and on the surface 64 which compensates for the difference in areas between the faces 45 and 65 of the rooms 38 and 39 (see figure 9).

 According to another variant illustrated in FIGS. 20 and 21, the axial balancing of the mobile assembly comprising the counter-ring 3 and the ring 11 is carried out using a series of pistons 55 fixed on the front of the counter-ring 3 and mounted to slide in bores 56 of the rotor. A piston 55 is provided in each interval delimited between two retractable partitions 4 consecutive. Axial passages 57 provided in the shoulder of the counter-ring 3, in the ring 16 and in the pistons 55 place the pressure chamber defined by each piston 55 in the corresponding bore 56 in communication with part of the vein 26 , delimited in the rotor between two consecutive partitions.

The cross section in the stream 26 between two consecutive partitions is equivalent to the cross section of each piston 55.

 The front surface of the counter ring 3, apart from the pistons, is equivalent to the rear surface of the ring 16 deduced from the shoulder 17, and these surfaces are balanced by the pressure taken in the middle of the reaction member. through channel 85.

 The surface of the piston in fact replaces the previous surface 70, and the surface 76 is formed by the front surface of the counter ring outside the surface taken into account by the pistons. Channels connect the surfaces under pressure, as in the case of FIG. 17.

 As a variant, if the counter ring 3 is not axially balanced in the rotor or in the stator, the annular chambers arranged between the rotor and the internal bore of the counter ring must have a variable width respectively which can be obtained by a groove made in the inner bore of the counter-ring and closed in the axial direction by a fixed part in translation belonging to the rotor (Figure 22).

We see in this figure 22 the ring with slots ensuring the watertightness of the vein on the side of the ring condO The slots of this ring 32 are adjusted in the axial slots of the counter ring, adjacent to the edge of the partitions, and complementary of the outer cylindrical surface of the counter-bag. This ring 32 participates with the partitions to angularly connect the counter-ring to the rotor.

 As a variant, the sealing of the vein is ensured, on the side of the counter-ring, by a cylindrical hoop 47 fixed in translation which remains adjacent to the edge of the retractable partitions whatever the position of the counter-ring (FIG. 23). .

 As shown in FIG. 24, the number of veins can be doubled, the veins being arranged in pairs of two concentric veins 62 associated with the same counter-ring, on each side. This arrangement of the veins makes it possible to double the cubic capacity of the engine while its size is only slightly greater than the size of the engine of FIG. 3.

 In all the examples described above, the machine comprises two identical and opposite counter-rings, two half-stators, two veins arranged on either side on the two ends of the rotor. the partitions working in each vein can be dissociated or not, the same partition being able to work at the same time in the two veins, and being in this way symmetrical, therefore naturally balanced.

 Of course, what is called a stator can become a rotor, and vice versa. It suffices to add known distribution means by rotating joint 86 (Figures 25 and 26).

 On the other hand, throughout the above discussion, the rotor is arranged inside the stator. Without changing either the operating principle or the shape of the parts, the rotor can be placed outside the stator (see Figure 27).

 Finally, as shown in FIG. 28, a cylindrical hoop can be added either between the rotor or in its sides, with appropriate fixing means (pin, screw, etc.) so as to limit the deformations sectors of the rotor between two notches.

Displacement control can be carried out by any mechanical, hydraulic or electrical system causing displacement
- or against the ring, insofar as the control system is associated with the rotor, this solution being that which is retained in the drawings
- Or the reaction member, the control system then being associated with the stator.

 The control means can be chosen from the following: cam, screw-nut, lever, jack, electromagnet with plunger, electric motor, and the combination of these means between them.

The engine following the addition has the following advantages in particular
- Its displacement can be varied at will, that is to say its power, its torque, or its speed, during operation. The displacement can vary continuously between the maximum value and the zero value.

 - The means used to make the displacement change are particularly simple and economical.

 - Sealing is very effectively ensured between the reaction organs and the stator, as well as at the level of the veins.

 - The reaction members are perfectly balanced from the hydraulic point of view, the pressure forces exerted on any one of their faces being automatically compensated by forces acting on an opposite face.

 - The counter-ring is hydraulically and mechanically balanced, balancing being made possible by the fact that this part is entirely contained in the rotor, which makes it possible to provide internal balancing channels.

 - The hydrostatic balancing of the parts is constant, and the parts do not deform, while there is no big effort to overcome to vary the displacement.

 - Each retractable partition 4 has a symmetrical design, is hydraulically balanced, and therefore does not risk being deformed, while the partitions of certain known machines are exposed to deformations at the notches intended for the passage of the reaction members.

Claims (18)

 1. Hydraulic machine comprising at least one hydraulic stream and, in each stream, on the one hand at least one reaction member integral with the stator of the machine and on the other hand retractable partitions integral with the rotor of the machine, means being designed to erase the retractable partitions as and when they come before a reaction member, to introduce a fluid under pressure into the vein downstream of these reaction members, and to allow the fluid to come out of the vein upstream of these same members, adjustment means making it possible to vary the width of the vein measured parallel to the axis of the machine, and characterized in that the hydraulic vein is delimited in the direction of the width between on the one hand a fixed surface of the stator and on the other hand the surface of an azially movable counter-ring, this counter-ring rotating with the rotor and comprising recesses inside which the retractable partitions, arranged radially t relative to the axis of the machine, can move.  2. Machine according to claim 1, characterized in that the front and rear ends of the reaction members abut, respectively, against a shoulder provided ettérieuresent on the counter-ring and against an external shoulder of a ring fixed on the rear part of the counter ring.  3. Machine according to claim 2, characterized in that the ring fixed to the rear part of the counter-ring comprises at least one inner lip which slides around a cylindrical surface of the rotor, two annular pressure chambers being thus delimited between the rotor and said ring to form a double-acting hydraulic cylinder capable of controlling the axial displacements of the counter-ring and of the ring.  4. Machine according to any one of the preceding claims, characterized in that a channel extends parallel to the axis of the motor in each reaction member, to ensure the axial balancing of said member.  5. Machine according to any one of the preceding claims, characterized in that the groove containing each reaction member in the stator is put under fixed pressure, at least one radial channel being provided through each reaction member to ensure balance. hydraulic of said reaction member in the radial direction, opening out inside said pressurizing groove, said fixed pressure being able to take any value from atmospheric pressure.  6. machine according to any one of claims 2 and 3, characterized in that the front part of the counter ring is housed in a first circular groove of the rotor, contiguous to a second circular groove of larger dimensions in which slides ltépaule- ment of the outer ring, the two annular chambers thus delimited in the rotor being placed in communication, respectively with chambers of equivalent cross-sections delimited in the stator by the rear part of the ring, and by a shoulder of the ring, by means of axial passages hollowed out in the counter-ring and in the ring, this to ensure the hydraulic balancing of the counter-ring and the ring in the axial direction.  7. Machine according to any one of claims 1 to 5, characterized in that the counter-ring is integral with a series of pistons mounted to slide parallel to the axis of the machine in the bores of the rotor, each interval defined between two consecutive retractable partitions being thus provided with a piston, the pressure chamber delimited at the front of each piston being placed in communication with the annular chamber delimited in the stator by the rear part of the ring by means of axial passages hollowed out in the counter-ring, in the ring, and in the corresponding piston.  8. Machine according to claim 7, characterized in that the front surface of the counter-ring, apart from the pistons, is equivalent to the rear surface of the ring deduced from the shoulder, these surfaces being balanced thanks to internal passages by the pressure taken in the middle of the reaction member.  9. Machine according to any one of the preceding claims, characterized in that the counter-ring has at least one radial passage ensuring communication between the vein and an annular hydraulic balancing chamber which is delimited between an external cylindrical surface of the rotor , an internal cylindrical surface of the counter-ring, a shoulder of the counter-ring, and an annular counter-piece adjacent to the edge of the retractable partitions, this annular balancing chamber having the same width whatever the axial position of the counter ring, this to ensure the hydraulic balancing of the counter ring and the ring in the radial direction.  10. Machine according to any one of the preceding claims, characterized in that the watertightness of the stream is ensured, from the stator OAOté, by a ring which is integral with the stator, the front face of which is adjacent to the edge of the retractable partitions , and whose internal cylindrical surface is adjacent to a complementary surface provided on the front part of the reaction members.  11. Machine according to claim 10, characterized in that there is provided in the stator, immediately behind the ring ensuring the tightness of the vein, and with regard to the face of each reaction member located at the opposite the machine axis, a clearance connected to a fluid return pipe, the clearances allowing the reaction members to be pressed slightly against the stator.  12. Machine according to any one of the preceding claims, characterized in that the watertightness of the vein is ensured, on the side of the counter-ring, by a notched ring which is integral with the rotor and which remains adjacent to the edge of the retractable partitions whatever the axial position of the counter-ring, this ring with slots cooperating with the partitions to angularly connect the counter-ring and the rotor.  13. Machine according to any one of claims 1 to 11, characterized in that the sealing of the vein is ensured, on the side of the counter-ring, by a cylindrical hoop fixed in translation which remains adjacent to the edge of the retractable partitions whatever the axial position of the counter-ring.  14. Machine according to any one of the preceding claims, characterized in that each reaction member has substantially the shape of a key, and has at least over part of its length a profile in the sector of a ring for engaging. in the vein.  15. Machine according to any one of claims 1 to 13, characterized in that each reaction member has a cylindrical shape, and is entirely contained in the stator.  16. Machine according to any one of claims 1 to 13, characterized in that each reaction member has a cylindrical shape, and is mounted between leather and flesh, that is to say only partially in the stator.  17. Machine according to any one of the preceding claims, characterized in that it comprises two half-rotors and two counter-rings arranged in identical ways on either side of the retractable partitions placed in the central part of the machine.  18. Machine according to any one of the preceding claims, characterized in that the veins are arranged in pairs, each couple comprising two concentric veins which are associated with the same counter-ring.