EP0067918A1 - Hydrostatic motor with axially sliding vanes - Google Patents

Abstract

1. A hydrostatic motor with vanes axially slidable in rotor lodgings and against a continuous stator bottom surface with recesses therein, comprising a circuit (7) for intercommunication between vanes (1) behind the latter, said circuit permitting complete transmission of pressures between vanes according to their variable location against said stator bottom surface with recesses therein (E), thereby ensuring accelerations and decelerations of axial sliding of the vanes as well as pressing of said vanes against the stator bottom surface with recesses therein, with the vanes retracted in their lodgings acting upon the vanes projecting out of their lodgings thanks to pressure increase in said intercommunication circuit, each vane being in contact in its rotor lodging with a pusher piston (6) for pressure transmission in said circuit (7) for intercommunication between vanes, characterized in that each vane is equipped with at least one valve (14) opening under the action of a magnetic stator force (FM) in the rotor bottom lodging to stator recess direction and closing under the action of a spring (19) or a portion of the stator bottom surface with recesses therein (E).

Description

The present invention relates to a hydrostatic motor with axial sliding vanes against a continuous surface of stator bottom with recesses.

The device according to the present invention is of the type of the Applicant's generation of devices comprising sliding pallets, with axial sliding, arranged in housings of the rotor, which pallets are each applied, in a constant and total manner, on a continuous surface of stator bottom, which can be a cycloidal surface, which can be deformed to present rectilinear zones or recesses suitable for the operation of the device, said recesses being able, moreover, to be made mobile.

Generally known, rotary hydraulic machines comprising sliding radial vanes coming to bear, with more or less force, against a peripheral surface with generator parallel to the general axis of rotation. Some of these radial vane machines provide a fluid chamber behind the pallets to exert a thrust on the pallets by means of pistons or not this thrust which can help springs arranged behind the pistons or behind the pallets.

The peripheral surface cooperating with the radial vanes is a smoothly curved surface that is smoothly ellipsoid or circular or lobed.

The present invention relates more particularly to a hydrostatic motor with axial sliding vanes in rotor housings and against a continuous surface of stator base with recesses, characterized in that it comprises an intercommunication circuit between pallets, behind these, which circuit allows an integral transmission of pressures between pallets according to their variable location against said stator bottom surface, which ensures accelerations and decelerations of the axial sliding of the pallets as well as the bonding of the pallets against the stator bottom surface.

A valve allows the supply of pressure to said intercommunication circuit.

Each pallet is in contact, in its rotor housing, with a pressure transmission push-piston in said intercommunication circuit.

According to one embodiment of the invention, each pallet is equipped with two valves arranged "head to tail" allowing hydraulic intercommunication between the bottom of the rotor housing of the pallet and a recess in the stator bottom surface.

According to another embodiment of the invention each pallet is equipped with at least one valve opening under the action of a stator magnetic force in the direction: bottom of rotor housing - stator recess and closing under the action of a spring or a recess portion of the stator bottom.

• - la figure 1 est une vue développée, schématique, d'un moteur hydrostatique conforme à l'invention, à l'endroit d'un évidement de fond statorique ;
• - la figure 2 est une vue développée d'un moteur hydrostatique selon quatre évidements de fond statorique et quatre phases de fonctionnement ;
• - les figures 3 et 4 sont des vues, respectivement de face et de profil, d'une palette coulissante d'un moteur selon l'invention, à l'endroit d'une rampe d'évidement s'écartant géométriquement d'un plan interstitiel entre le rotor et le stator ;
• - les figures 5 et 6 sont des vues, respectivement de face et de profil, d'une palette coulissante d'un moteur selon l'invention, à l'endroit d'une plage d'évidement, parallèle au plan interstitiel entre rotor et stator ;
• - les figures 7 et 8 sont des vues, respectivement de face et de profil, d'une palette coulissante d'un moteur selon l'invention, à l'endroit d'une rampe de fond statorique se rapprochant géométriquement du plan interstitiel entre rotor et stator ;
• - les figures 9 et 10 sont des vues de face et de profil d'une palette coulissante d'un moteur selon l'invention dans lequel l'évidement de fond statorique est mis hors service pour un fonctionnement en roue libre ;
• - la figure 11 est une vue, à deux moments de son fonctionnement d'une palette coulissante représentée en coupe et en coupe partielle, selon une autre forme de réalisation.

Other characteristics and advantages of the present invention will emerge from the description which follows, given with reference to the appended drawings in which:

• - Figure 1 is a developed, schematic view of a hydrostatic motor according to the invention, at the location of a stator bottom recess;
• - Figure 2 is a developed view of a hydrostatic motor according to four stator bottom recesses and four operating phases;
• - Figures 3 and 4 are views, respectively from the front and side, of a sliding pallet of an engine according to the invention, at the location of a recess ramp deviating geometrically from a plane interstitial between the rotor and the stator;
• FIGS. 5 and 6 are views, respectively from the front and from the side, of a sliding pallet of an engine according to the invention, at the location of a recess range, parallel to the interstitial plane between the rotor and stator;
• - Figures 7 and 8 are views, respectively from the front and from the side, of a sliding pallet of an engine according to the invention, at the location of a stator bottom ramp which is geometrically close to the interstitial plane between the rotor and stator;
• - Figures 9 and 10 are front and side views of a sliding pallet of an engine according to the invention in which the stator bottom recess is put out of service for freewheeling operation;
• - Figure 11 is a view, at two times of its operation of a sliding pallet shown in section and in partial section, according to another embodiment.

In the diagram of Figure 1 are shown several sliding pallets at different times of their operation, which pallets 1 are each housed in a housing 2 formed in a rotor R opposite a stator bottom S having recesses one of which d 'them E has, relative to an interstitial plane P between rotor and stator and relative to a rotor displacement F, a ramp 3 deviating geometrically from said plane, a range 4 parallel to said plane and a ramp 5 approaching geometrically from said plane .

Each pallet 1 is in contact, in its housing, with a push-piston 6 disposed in a channel 6A in communication with an auxiliary circuit 7 made in the rotor. All the channels 6A are in communication with said auxiliary circuit 7 and are therefore all in intercommunication.

In accordance with the diagram developed in FIG. 1 relating to the behavior of the sliding pallets as a function of a single recess E, there is, owing to the rotor displacement F, a withdrawal of the sliding pallet 1 in contact with the ramp 5 which geometrically approximates the interstitial plane P. Due to this withdrawal, the interested pallet 1, using its push piston 6, communicates an additional pressure in the auxiliary circuit 7. This pressure acts behind the push piston 6 of the other paddles and in particular those whose front spout is in contact with the ramp 3 which deviates geometrically from the interstitial plane P and which come out of their housing 2, taking into account the rotor displacement F. The pressure in the auxiliary circuit 7 s' also exerts, in particular on the sliding pallets which are in an active zone of operation of the recess E where the area 4 of the recess is parallel to the interstitial plane P between the rotor and the stator.

There is therefore always a recessed pallet for an active pallet projecting outside the housing. This action of the pushers of the recessed pallets on the protruding pallets outside the housing may be sufficient to maintain a satisfactory application or bonding of the pallets against the continuous surface of the stator bottom with recesses of the device.

Stator electromagnets can obviously be provided to possibly complete said bonding of the pallets. The auxiliary circuit 7 is supplied with high pressure HP by a valve 8 and, in operation, the pressure prevailing in the auxiliary circuit 7 is a pressure HP 'greater than the pressure HP. In other words HP '= HP + Fl; Fl being the pushing force of the re-entrant pallet andSS being the active surface of the push-button 6 for transmitting pressure. The application force F2 of the pallet projecting outside the housing is equal to the pressure F1.

In Figure 2 have been represented four different operating phases I, II, III and IV. Phases I and II are propulsion phases with an HP input and a BP output by recess. Phase III corresponds to a freewheeling phase with closed input and output and phase IV represents possible braking or pump operation with low pressure LP and high pressure HP circuits.

In the embodiments of Figures 3 to 10, each pallet 1 is equipped with a push-piston 6, spring 9 and single acting, pushing the pallet until it comes into contact with the ramps 3 or 5 or with the range 4 of each recess E of the continuous surface of the stator background.

The pushing force is given, jointly, by the spring 9 and a hydraulic pressure supplied by the high pressure HP maintained under pressure by a valve 10 in communication by a channel 11 with the auxiliary circuit 7.

When the engine rotates, the ramps 5 which are geometrically close to the interstitial plane P exert a pressure on the pallets which are in contact with them thus causing these pallets to withdraw in their housing 2 and, consequently, a rise in pressure in the auxiliary circuit, transmitted by the pusher 6, so that HP ') HP.

The pressure HP 'then exerts a push on the other pallets holding them against the stator bottom surface and allowing the acceleration of the pallets projecting outside the housing. The pallets are hydraulically connected to each other and can no longer take off.

Each pallet is equipped with two valves 12 and 13 arranged "head to tail" allowing hydraulic intercommunication between the bottom of the housing 2 and the recess E of the stator bottom surface.

At start-up, the pressure HP which arrives in the recess E causes the opening of the intercommunication valve 12 and of the valve 10 of the auxiliary circuit 7 of the pushers.

In FIGS. 3 and 4, the pallet sticks under the action of the spring 9 against the ramp 3 which deviates geometrically from the interstitial plane P.

In Figures 5 and 6, the pallet is considered in the active phase. The front spout of the pallet is in contact with the area 4 of the stator bottom which is parallel to the interstitial plane P. Due to this position of the pallet, the valves 12 and 13 are closed and the pallet is glued against the stator area by the action of its pusher 6.

The pressure HP ′ which then prevails in the auxiliary circuit 7 by pressure build-up due to the fact that the vanes are also recessed is greater than the pressure HP and comes to close the valve 10 for intercommunication between this auxiliary circuit and the recess E.

In FIGS. 7 and 8, the pallet 1 is shown in contact with the ramp 5 which approaches geometrically the interstitial plane, so that under the action of this ramp the pallet returns to its housing, provo as for the opening of the interconnection valve 13 between the bottom of the housing 2 of the pallet and the recess E. Under these conditions, we are witnessing the hydraulic exhaust BP of the recess E. In the figures 9 and 10, the pressure in the recess E is in the relation BP '〈BP 〈HP and cannot therefore cause the opening of the intercommunication valve 12. It then opposes a zero pressure behind the pallet. The pallet cannot descend and the recess E is put out of service, hence a freewheeling operation. The action of an electromagnet EM can be provided to help maintain the pallet in total withdrawal in its housing.

In the embodiment shown in Figure 11, the pallet is equipped with one or more valves placed in the same direction. A magnetic force FM coming from the stator causes the pallet to stick against the continuous surface of the stator bottom and the opening and closing of the valve designated by the general reference 14, as a function of the position of the pallet relative to the ramps 3 and 5 and at range 4 of the stator recess E. Indeed, a head 15 of the valve, itself attracted by the magnetic force FM, therefore also comes into contact with the ramps 3 and 5 and the range 4.

During the active high pressure phase, the valve is closed and traps a hydraulic volume behind the pallet which prevents it from coming off. The magnetic force FM, can then not be exerted.

The valve head 15 is integral with a rod 16 carrying a disc 17 with openings 18. A spring 19 is interposed between the disc 17 and an annular bottom 20 formed in the pallet. In addition, the disc 17 is capable of abutting against an annular shoulder 21 also made in the pallet.

At start-up, hydraulic pressure from the auxiliary circuit 7 causes the pallets to be actuated.

In all the embodiments, the pallets can have a curved portion 22 of contact with the continuous stator surface and a compensating portion 23 exposed to the pressure of the fluid so that this pressure is exerted substantially perpendicular to the stator surface, thus improving the application of the pallet against the stator surface. Each pallet can also be provided with an additional surface exposed to pressure and extending laterally at 24 to the pallet and continuing inside the pallet housing. This additional surface makes it possible to avoid any tilting of the pallet and enables the pallet to be sealed against its housing on a contact line 25 situated at the rear edge of the lateral face of the pallet opposite to that exposed at 24 at the preponderant pressure.

It is understood that the present invention has only been described and shown as a preferred example and that it is possible to provide equivalences in its constituent elements without, however, departing from the scope of said invention which is defined. in the claims which follow.

Claims (8)

1. Hydrostatic paddle motor with axial sliding in rotor housings and against a continuous surface of stator base with recesses, characterized in that it comprises a circuit (7) for intercommunication between paddles (1), behind them, which circuit allows an integral transmission of pressures between pallets according to their variable location against said stator bottom surface with recesses (E), which ensures accelerations and decelerations of the axial sliding of the pallets as well as the bonding of said pallets against the stator bottom surface to recesses, the pallets recessed in their housings acting, by pressure build-up in said intercommunication circuit, on the pallets projecting outside the housing. 2. Hydrostatic motor according to claim 1, characterized in that a valve (8) allows the supply of pressure to said circuit (7) of intercommunication between pallets. 3. Hydrostatic motor according to claim 1, characterized in that a valve (10) for supplying pressure to said intercommunication circuit (7) draws from the active zone of each recess (E) of the stator bottom surface. 4. Hydrostatic motor according to any one of claims 1 to 3, characterized in that each pallet is in contact, in its rotor housing, with a push-piston (6) for transmitting pressure in said circuit (7) of intercommunication between pallets. 5. Hydrostatic motor according to claim 4, characterized in that the push-piston is equipped with a spring (9) pushing the pallet to bring it into contact with the different ramps (3-5) and ranges (4) of the recesses (E) in the stator bottom surface. 6. Hydrostatic motor according to any one of claims 1 to 5, characterized in that each pallet is equipped with two valves (12-13) arranged "head to tail" allowing hydraulic intercommunication between the bottom of the rotor housing (2) of the pallet and a recess (E) in the stator base surface. 7. Hydrostatic motor according to any one of claims 1 to 5, characterized in. that each pallet is equipped with at least one valve (14) opening under the action of a stator magnetic force (FM) in the direction: bottom of rotor housing - stator recess and closing under the action of a spring (19) or a recess portion of the stator bottom (E). 8. Hydrostatic motor according to any one of claims 1 to 7, characterized in that a rotor magnetic force (EM) allows the pallet to be held in total withdrawal in its rotor housing in order to obtain freewheeling operation.

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