EP3037661B1 - Device for automatically switching the displacement of an axial piston machine - Google Patents

Device for automatically switching the displacement of an axial piston machine Download PDF

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Publication number
EP3037661B1
EP3037661B1 EP15201484.1A EP15201484A EP3037661B1 EP 3037661 B1 EP3037661 B1 EP 3037661B1 EP 15201484 A EP15201484 A EP 15201484A EP 3037661 B1 EP3037661 B1 EP 3037661B1
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EP
European Patent Office
Prior art keywords
control
spool
pressure
machine
spring
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EP15201484.1A
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German (de)
French (fr)
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EP3037661A1 (en
Inventor
Enrico Rigolon
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Poclain Hydraulics Industrie
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Poclain Hydraulics Industrie
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03C—POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
    • F03C1/00—Reciprocating-piston liquid engines
    • F03C1/02—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders
    • F03C1/06—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinder axes generally coaxial with, or parallel or inclined to, main shaft axis
    • F03C1/0678—Control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03C—POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
    • F03C1/00—Reciprocating-piston liquid engines
    • F03C1/02—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders
    • F03C1/06—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinder axes generally coaxial with, or parallel or inclined to, main shaft axis
    • F03C1/0678—Control
    • F03C1/0686—Control by changing the inclination of the swash plate
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/26—Control
    • F04B1/30—Control of machines or pumps with rotary cylinder blocks
    • F04B1/32—Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block
    • F04B1/324—Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block by changing the inclination of the swash plate
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/001—Servomotor systems with fluidic control

Definitions

  • the invention relates to a device for controlling the displacement of an axial piston machine with variable displacement.
  • the invention relates to a device for a machine for automatically switching between a small and a large displacement by varying the inclination of the plate, depending on certain pressures.
  • the inclination of the plate is variable with respect to a plane perpendicular to the axis of rotation RR 'by means of jacks V1, V2 and makes it possible to adjust the stroke of the pistons Q and thus the displacement (cf. Figures 2a and 2b , for respectively small and large displacement).
  • the complete machine incorporates several elements.
  • a common housing comprising a cover is at the same time the structure pump / motor BC, Q1, Q2, with the plate IP, and hydraulic means which allow on the one hand to control the arrivals and the returns of oil towards the Q pistons and on the other hand to control the inclination of the IP tray to vary the displacement.
  • These hydraulic means comprise two separate units S1 (pressure control), S2 (plateau control) for these two functions, which use valves and complex connections.
  • S1 pressure control
  • S2 plateau control
  • these hydraulic means must be integrated in the housing and in particular in the lid.
  • the unit S1 typically comprises a four-port distributor, three positions.
  • the S2 unit for controlling the plate it comes in several embodiments: non-automatic and automatic switching.
  • FIGs 4a, 4b , 4c present respectively a lateral section, front and a hydraulic diagram of a machine as existing in the prior art.
  • the figure 4d represents such a system S2 in three dimensions.
  • the systems S1, S2 have been identified in the figures. Both are in the same plane.
  • control pressure line Ps which is also independent.
  • control is only controlled by the control pressure line Ps.
  • a box B1 which houses a control spool B2 which can be switched according to a switching axis ⁇ between two positions by a control pressure Ps.
  • a spring B3 opposes the movement of said spool B2. The switching is done if the force Fd exerted by the pressurized oil Ps is greater than the opposing force Fo of the spring B3.
  • the Figures 5a, 5b , 5c, 5d present respectively a lateral section, front and a hydraulic diagram of a machine as existing in the prior art.
  • the machine comprises an additional automation unit S3.
  • this unit S3 is not in the same plane as the others and requires a rather heavy adaptation of the architecture compared to the machine of the Figures 4a, 4b and 4d .
  • the unit S3 comprises a two port valve a position in the default locked position and controlled by a line which is controlled by the highest pressure among P1 and P2.
  • the valve of the unit S3 comprises a pin, a drawer and a spring that the pin can compress by driving the drawer in translation.
  • the engine pressure decreases and the hydraulic load of the oil acting on the pin is less than the spring value.
  • the drawer becomes jamming and the circuits of two cylinders no longer discharge via the unit S3 to the tank.
  • the pressure in these circuits then increases.
  • the plate moves from its maximum displacement configuration to its minimum displacement configuration. Conversely, in difficult working conditions, the hydraulic load increases and the drawer does not block.
  • the oil from the cylinder circuits then discharges into the tank and the plate recovers its maximum displacement configuration.
  • Kayaba document JPH01116301 (or published under JP 2654953 ) presents another embodiment S2 'of the platen control unit.
  • the drawer A2 is held in the rest position a spring A3, connected to one end of the drawer A2 and a plug A4.
  • the spring A3 exerts a force along the axis ⁇ which tends to move the drawer A2 away from the plug A4.
  • the cap A4 closes the case tightly.
  • a cavity A5 which can receive the oil from the control pressure Ps.
  • the pressurized control oil Ps exerts a force on the collinear slide A2 in the same direction as the spring A3.
  • the housing A1 comprises a pressurized oil inlet Pm at another end of the drawer A2, which can exert a force on the drawer, in the opposite direction to that of the spring A3 exerted on the drawer A2.
  • the movement of the slide A2 depends on the pressures Pm, Ps and the spring A3.
  • the drawer A2 is held in the rest position.
  • this pressure increases, it moves the A2 drawer by compressing the spring A3.
  • the switching pressure Pm When the switching pressure Pm is activated, the positioning of the slide A2 is automatically performed as a function of the value of this switching pressure Pm. Nevertheless, it is not allowed to obtain a simple correspondence between the position of the slide A2 and the values of the pressures A6 and Ps.
  • the device 10 is a control unit of the plate S2, integrated in a machine axial piston 20 of variable displacement by inclination of the plate.
  • the device 10 is a selector disposed in a hydraulic circuit 30 (see FIG. figure 10a , 10b ), the circuit being essentially similar to that described in the introduction (cf. EP 2 592 263 ).
  • the hydraulic circuit 30 comprises a first cylinder line 31 and a second cylinder line 32, connected respectively to the cylinders 31a and 32a which allow the inclination of the plate 21 according to the pressures to which they are subjected.
  • the device 1 has two positions: in a rest position, the two cylinder lines 31, 32 are empty, in a working position, the two cylinder lines 31, 32 are pressurized.
  • a first supply line 33 connects a pressure control unit S1 to the pistons of the machine 20 and a second supply line 34 connects the pistons of the machine 20 to the unit S1. It is specified that the roles can be reversed depending on the direction of operation of the machine (forward or reverse).
  • the supply lines 33, 34 are fed at pressures P1, P2.
  • a pressure control unit S1 distributes the pressures P1, P2 in the supply lines 33, 34. Depending on the use (engine, pump, forward, reverse), each line 33, 34 can bring or recover the oil, at high or low pressure.
  • the device 10 is typically housed in a housing 23 of the machine 20, the housing comprising a first output 101, a second output 103, a first input 102, a second input 104 (see FIG.
  • FIGS 11a, 11b The first output 101 of the housing 23 is connected to the first jack line 31 and the second output 103 is connected to the second jack line 32. Note that the device 10 operates similarly with a single input and output instead of the two inputs and outputs 101, 102, 103, 104.
  • control spool 110 has two ends 110a, 110b.
  • the control spool 110 comprises at least one circular groove 111, 112, and preferably as mentioned above a first groove 111 which connects the first inlet 102 to the first outlet 101 and a second groove 112 which connects the second inlet 104 to the second outlet 103.
  • the second slide 130 comprises a head 131 and a body 132, the head sliding in a plug 120 located on the sliding axis ⁇ .
  • the axial force of the control pressure Ps is exerted via oil through a control pressure line 105 in a cavity formed by the housing 23 and the first end of the piston 110a.
  • the spring 140 exerts its force on the body 132 of the second slide 130 and on the second end of the control slide 110.
  • This control pressure line 105 is typically on / off mode, that is to say that alternately applies a Ps pressure or no pressure.
  • the control pressure line 105 may include a restriction, preferably an orifice of 0.5 mm in diameter.
  • the axial force of the switching pressure Pm is exerted via oil via a switching pressure line 121 into a cavity 122 formed by said plug 120 and the head 131 of the second slide 130.
  • the switching pressure line 121 is in said plug 120.
  • the first supply line 33 is stitched by a first sample 33a to feed the first input 102 and the second supply line 34 is stitched by second sample 34a to feed the second input 104.
  • the housing 23 guides the control spool 110.
  • the first end 110a of the control spool 110 and the housing 23 form a cavity 113, of variable size according to the position of the control spool 110.
  • the displacement pressure line 105 supplies said cavity 113 in pressure control oil Ps.
  • the control pressure Ps is constant. In addition, it is typically between 20 and 40 bar.
  • the device 10 is such that the pressurized oil exerts a displacement force Fd on the control spool 110 according to the sliding axis ⁇ , towards the second slide 130.
  • the pressure Ps is adjustable by the user to set the operation of the machine.
  • the communication between the inputs 102, 104 and outputs 101, 103 respectively is via the two circular grooves 111, 112 (see FIG. Figures 8, 9 and 11a for the rest position, and figure 11b for the working position - only the groove 111 is shown) drawn on the control spool 110 when the cavity 113 is subjected to the control pressure Ps.
  • These grooves 111, 112 also have a flow restrictor function.
  • the second slide 130 slides in the plug 120 along the sliding axis ⁇ , which means that the movements of the control spool 110 and the second spool 130 are collinear.
  • the plug 120 thus guides the second slide 130.
  • the head 131 and the plug 120 form a cavity 122, of variable size according to the position of the second slide 130.
  • the switching pressure line 121 supplies said cavity 122 oil under pressure switching Pm.
  • the switching pressure Pm typically corresponds to one of the pressures P1, P2 for supplying the machine 20. It is therefore variable as a function of the load of the machine 20. It is typically between 40 and 250 bar. In this way, the device 10 is such that the pressurized switching oil Pm in the cavity 122 exerts a counter-force Fc on the head 131 of the second slide 130 according to the sliding axis ⁇ , in the direction of the control spool 110.
  • the spring 140 is located between the second end 110b of the control spool 110 and the body 132 of the second spool 130.
  • the spring 140 exerts thrust forces (it is constantly in compression).
  • the spring 140 is immersed in the oil.
  • a drainage circuit 150 makes it possible to supply the area of the spring 140 with oil.
  • the second end 110b of the control spool 110 comprises a recess 114 in which the spring 140 is partially housed (see FIG. Figures 8 and 9 in particular).
  • the body 132 of the second slide 130 is adapted to come into contact with the second end 110b when the spring 140 is compressed inside said recess 114 of the control spool 110.
  • the diameter of the body 132 of the second drawer 130 is for example equal to or greater than the diameter of the second end 110b.
  • the drainage circuit 150 opens into the recess 114.
  • the second end 110b of the control slide 110 is not in direct contact with the second slide 130.
  • the second end 110b of the control slide 110 can not come into contact with the body 132 of the second slide 130: either the spring having a stiffness such that the displacement force Fd and the counterforce Fc can compress enough, or because its volume of material prevents contact when fully compressed.
  • the spring 140 for its part, opposes the movements of the control spool 110 and the second spool 130.
  • a second fixed spool 130, the spring therefore exerts its opposing force Fo (said force being equal to the product of its stiffness and its difference in length with its empty length) in opposite direction to that of the displacement force Fd.
  • a fixed control spool 110, the spring 140 thus exerts its opposing force Fo in opposite direction to that of the counter force Fc.
  • the opposing force of the spring Fo on a part depends on the position of the part situated on the other side, since this position has an influence on the length of the compressed spring 140.
  • the control spool 110 is assumed to be in the working position, that is to say that Fd> Fo, on then applies Fc to the second drawer, with Fc> Fo.
  • the spring 140 will compress until the body 132 of the second slide 130 is in contact with the second end 110b of the control spool 110. This is then two solid parts in contact, and the displacement is done in one direction or the other depending on the value of the forces: the characteristics of the various elements (the control pressure Ps, the stiffness of the spring 140, choice of surfaces, etc.) are chosen during the design so that Fc can be greater than Fd, in this way the control spool 110 passes into the rest position.
  • the drawer 110 returns to the working position, when the switching pressure Pm decreases and Fc ⁇ Fd checks.
  • the decrease of the switching pressure Pm is related to the load of the machine 20 (rise, fall, intense use, etc.).
  • a device with non-automatic mode that takes full advantage of the spring to maintain the device 10 in the rest position and an automatic mode that eliminates the spring in order to be able to switch between the rest position and the working position depending solely on the control pressure Ps and Pm switching.
  • the first sample 33a is connected to the first cylinder line 31 by the first inlet 102, the groove 111 and the high pressure outlet 101, to enable the activation of the cylinder 31a.
  • the cylinder lines 31, 32 are no longer supplied with oil under pressure.
  • the lines of cylinders 31, 32 are both connected to a line of emptiness.
  • the machine 20 is said to have large displacement, respectively small displacement.
  • the unit S1 comprises a distributor 42 six ports, five positions.
  • the supply lines 33, 34 are divided and are each connected to two ports of the distributor 42.

Description

DOMAINE TECHNIQUE GENERALGENERAL TECHNICAL FIELD

L'invention concerne un dispositif de contrôle de cylindrée d'une machine à pistons axiaux à cylindrée variable.The invention relates to a device for controlling the displacement of an axial piston machine with variable displacement.

En particulier, l'invention concerne un dispositif pour une machine permettant de commuter automatiquement entre une petite et une grande cylindrée par variation d'inclinaison de plateau, en fonction de certaines pressions.In particular, the invention relates to a device for a machine for automatically switching between a small and a large displacement by varying the inclination of the plate, depending on certain pressures.

ETAT DE L'ARTSTATE OF THE ART

Les machines à pistons axiaux sont des machines pouvant fonctionner soit en pompe, soit en moteur. Pour cela (voir figure 1 ), la machine comprend :

  • un bloc-cylindre BC composé d'une pluralité de cylindres C répartis en cercle autour d'un axe de rotation R-R',
  • une série de pistons Q1, Q2, ..., répartis en cercle autour du même axe de rotation R-R', guidés à coulisser axialement respectivement dans les cylindres C du bloc-cylindres BC et reliés chacun à deux conduits d'huiles d'admission et de refoulement,
  • un plateau inclinable IP, monté à rotation relativement au bloc-cylindre BC, qui sert d'appui à l'extrémité des pistons Q1, Q2,... externes aux cylindres C,
Axial piston machines are machines that can operate either as pumps or as motors. For this (see figure 1 ), the machine includes:
  • a cylinder block BC composed of a plurality of cylinders C distributed in a circle about an axis of rotation R-R ',
  • a series of pistons Q1, Q2, ..., distributed in a circle around the same axis of rotation R-R ', guided to slide axially respectively in the cylinders C of the cylinder block BC and each connected to two lines of oil admission and refoulement,
  • an IP tilting tray, rotatably mounted relative to the cylinder block BC, which serves to support the end of the pistons Q1, Q2, ... external to the cylinders C,

L'inclinaison du plateau est variable par rapport à un plan perpendiculaire à l'axe de rotation R-R' grâce à des vérins V1, V2 et permet de régler la course des pistons Q et donc de la cylindrée (voir figures 2a et 2b , pour respectivement la petite et la grande cylindrée). La machine complète intègre plusieurs éléments. Dans un boîtier commun comprenant un couvercle se trouve à la fois la structure pompe/moteur BC, Q1, Q2, avec le plateau IP, et des moyens hydrauliques qui permettent d'une part de contrôler les arrivées et les retours d'huile vers les pistons Q et d'autre part de contrôler l'inclinaison du plateau IP pour faire varier la cylindrée.The inclination of the plate is variable with respect to a plane perpendicular to the axis of rotation RR 'by means of jacks V1, V2 and makes it possible to adjust the stroke of the pistons Q and thus the displacement (cf. Figures 2a and 2b , for respectively small and large displacement). The complete machine incorporates several elements. In a common housing comprising a cover is at the same time the structure pump / motor BC, Q1, Q2, with the plate IP, and hydraulic means which allow on the one hand to control the arrivals and the returns of oil towards the Q pistons and on the other hand to control the inclination of the IP tray to vary the displacement.

Ces moyens hydrauliques comprennent deux unités distinctes S1 (contrôle des pressions), S2 (pilotage du plateau) pour ces deux fonctions, qui utilisent des valves et des liaisons complexes.
Or, ces moyens hydrauliques (et ses deux unités) doivent être intégrés dans le boitier et en particulier dans le couvercle.These hydraulic means comprise two separate units S1 (pressure control), S2 (plateau control) for these two functions, which use valves and complex connections.
However, these hydraulic means (and its two units) must be integrated in the housing and in particular in the lid.

En référence à la figure 3 , l'unité S1 comprend typiquement un distributeur quatre ports, trois positions.With reference to the figure 3 , the unit S1 typically comprises a four-port distributor, three positions.

Quant à l'unité S2 de pilotage du plateau, elle se décline sous plusieurs modes de réalisation : la commutation non-automatique et automatique.As for the S2 unit for controlling the plate, it comes in several embodiments: non-automatic and automatic switching.

Commutation non-automatiqueNon-automatic switching

Les figures 4a, 4b , 4c présentent respectivement une section latérale, frontale et un schéma hydraulique d'une machine telle qu'existant dans l'art antérieur. La figure 4d représente un tel système S2 en trois dimensions. Les systèmes S1, S2 ont été identifiés sur les figures. Les deux sont situés dans le même plan.The Figures 4a, 4b , 4c present respectively a lateral section, front and a hydraulic diagram of a machine as existing in the prior art. The figure 4d represents such a system S2 in three dimensions. The systems S1, S2 have been identified in the figures. Both are in the same plane.

L'unité S2 comprend une valve de pilotage cinq ports et deux positions qui permettent :

  • dans une position standard de mettre les vérins d'inclinaison sous une mise à vide, vers le réservoir par exemple,
  • dans une position pilotée d'alimenter les vérins d'inclinaison V1, V2 respectivement sous pression P1 et P2, en fonction du sens de fonctionnement : l'une des lignes sera en haute pression et l'autre sera en basse pression. Les pressions P1 et P2 peuvent s'inverser si la machine fonctionne en sens inverse, ou si la machine est en traction ou en retenue).
The unit S2 comprises a five port control valve and two positions that allow:
  • in a standard position to put the tilt cylinders under a vacuum, to the tank for example,
  • in a controlled position to supply the tilt cylinders V1, V2 respectively under pressure P1 and P2, depending on the direction of operation: one of the lines will be at high pressure and the other will be at low pressure. The pressures P1 and P2 can be reversed if the machine operates in the opposite direction, or if the machine is in tension or restraint.

Le pilotage est effectué par une ligne de pression de commande Ps indépendante elle aussi.The control is carried out by a control pressure line Ps which is also independent.

Dans ce mode de réalisation, le pilotage est uniquement contrôlé par la ligne de pression de commande Ps.In this embodiment, the control is only controlled by the control pressure line Ps.

Sur la figure 4d , on remarque un boitier B1 qui loge un tiroir de pilotage B2 pouvant être commuté selon un axe de commutation Δ entre deux positions par une pression de commande Ps. Un ressort B3 s'oppose au mouvement dudit tiroir B2. La commutation se fait si la force Fd exercée par l'huile sous pression Ps est plus importante que la force d'opposition Fo du ressort B3.On the figure 4d a box B1 is noted which houses a control spool B2 which can be switched according to a switching axis Δ between two positions by a control pressure Ps. A spring B3 opposes the movement of said spool B2. The switching is done if the force Fd exerted by the pressurized oil Ps is greater than the opposing force Fo of the spring B3.

Commutation automatiqueAutomatic switching

Les figures 5a, 5b , 5c, 5d présentent respectivement une section latérale, frontale et un schéma hydraulique d'une machine telle qu'existant dans l'art antérieur. Dans ce mode de réalisation, la machine comprend une unité d'automatisation S3 supplémentaire. Comme on peut le voir sur la figure 4a, cette unité S3 ne se situe pas dans le même plan que les autres et nécessite une adaptation assez lourde de l'architecture par rapport à la machine des figures 4a, 4b et 4d .The Figures 5a, 5b , 5c, 5d present respectively a lateral section, front and a hydraulic diagram of a machine as existing in the prior art. In this embodiment, the machine comprises an additional automation unit S3. As can be seen on the figure 4a , this unit S3 is not in the same plane as the others and requires a rather heavy adaptation of the architecture compared to the machine of the Figures 4a, 4b and 4d .

Le document WO 2007/115828 décrit un tel dispositif.The document WO 2007/115828 describes such a device.

L'unité S3 comprend une valve deux ports une position en position bloquée par défaut et pilotée par une ligne qui est contrôlée par la pression la plus élevée parmi P1 et P2. La valve de l'unité S3 comprend une goupille, un tiroir et un ressort que la goupille peut compresser en entrainant le tiroir en translation. En condition de travail légère, la pression du moteur diminue et la charge hydraulique de l'huile qui agit sur la goupille est inférieure à la valeur du ressort. Le tiroir devient bloquant et les circuits de deux vérins ne se déchargent plus via l'unité S3 vers le réservoir. La pression dans ces circuits augmente alors. Le plateau se déplace de sa configuration de cylindrée maximale à sa configuration de cylindrée minimale. Inversement, en condition de travail difficile, la charge hydraulique augmente et le tiroir ne bloque pas. L'huile des circuits de vérins se décharge alors dans le réservoir et le plateau récupère sa configuration de cylindrée maximale.The unit S3 comprises a two port valve a position in the default locked position and controlled by a line which is controlled by the highest pressure among P1 and P2. The valve of the unit S3 comprises a pin, a drawer and a spring that the pin can compress by driving the drawer in translation. In light working conditions, the engine pressure decreases and the hydraulic load of the oil acting on the pin is less than the spring value. The drawer becomes jamming and the circuits of two cylinders no longer discharge via the unit S3 to the tank. The pressure in these circuits then increases. The plate moves from its maximum displacement configuration to its minimum displacement configuration. Conversely, in difficult working conditions, the hydraulic load increases and the drawer does not block. The oil from the cylinder circuits then discharges into the tank and the plate recovers its maximum displacement configuration.

Alternativement, comme représenté sur la figure 6 , le document Kayaba JPH01116301 (ou publié sous JP 2654953 ) présente un autre mode de réalisation S2' de l'unité de pilotage du plateau.Alternatively, as shown on the figure 6 , Kayaba document JPH01116301 (or published under JP 2654953 ) presents another embodiment S2 'of the platen control unit.

Cette unité S2' comprend un boîtier A1 qui loge un tiroir de pilotage A2 pouvant être commuté selon un axe de commutation Δ entre deux positions par une pression de commande Ps:

  • une position de travail dans laquelle le tiroir de pilotage assure une liaison entre une entrée recevant une pression d'alimentation et une sortie reliée au vérin V1 (ou V2),
  • une position de repos dans laquelle le tiroir de pilotage A2 interrompt ladite liaison.
This unit S2 'comprises a housing A1 which houses a control spool A2 which can be switched according to a switching axis Δ between two positions by a control pressure Ps:
  • a working position in which the control spool provides a connection between an input receiving a supply pressure and an output connected to the cylinder V1 (or V2),
  • a rest position in which the control spool A2 interrupts said connection.

Le tiroir A2 est maintenu en position de repos un ressort A3, relié à une extrémité du tiroir A2 et à un bouchon A4. Le ressort A3 exerce une force selon l'axe Δ qui tend à éloigner le tiroir A2 du bouchon A4. Le bouchon A4 ferme le boitier de façon étanche.The drawer A2 is held in the rest position a spring A3, connected to one end of the drawer A2 and a plug A4. The spring A3 exerts a force along the axis Δ which tends to move the drawer A2 away from the plug A4. The cap A4 closes the case tightly.

En outre, entre le bouchon A4 et le tiroir A2 se trouve une cavité A5 qui peut recevoir l'huile de la pression de commande Ps. L'huile sous pression de commande Ps exerce une force sur le tiroir A2 colinéaire de même sens que le ressort A3.Further, between the plug A4 and the slide A2 is a cavity A5 which can receive the oil from the control pressure Ps. The pressurized control oil Ps exerts a force on the collinear slide A2 in the same direction as the spring A3.

Le boîtier A1 comprend une arrivée d'huile sous pression Pm au niveau d'une autre extrémité du tiroir A2, qui peut exercer une force sur le tiroir, de sens contraire à celle du ressort A3 exercée sur le tiroir A2.The housing A1 comprises a pressurized oil inlet Pm at another end of the drawer A2, which can exert a force on the drawer, in the opposite direction to that of the spring A3 exerted on the drawer A2.

De cette façon, le déplacement du tiroir A2 dépend des pressions Pm, Ps et du ressort A3. En particulier, lorsque la force exercée par la pression Ps est inférieure à celle exercée par le ressort A3, le tiroir A2 est maintenu en position de repos. Lorsque cette pression augmente, elle permet de déplacer le tiroir A2 en comprimant le ressort A3.In this way, the movement of the slide A2 depends on the pressures Pm, Ps and the spring A3. In particular, when the force exerted by the pressure Ps is lower than that exerted by the spring A3, the drawer A2 is held in the rest position. When this pressure increases, it moves the A2 drawer by compressing the spring A3.

Lorsque l'on active la pression de commutation Pm, le positionnement du tiroir A2 s'effectue automatiquement en fonction de la valeur de cette pression de commutation Pm. Néanmoins, il n'est pas permis d'obtenir une correspondance simple entre la position du tiroir A2 et les valeurs des pressions A6 et Ps.When the switching pressure Pm is activated, the positioning of the slide A2 is automatically performed as a function of the value of this switching pressure Pm. Nevertheless, it is not allowed to obtain a simple correspondence between the position of the slide A2 and the values of the pressures A6 and Ps.

En effet, lorsque le ressort A3 est comprimé au maximum par la pression Ps, la pression de commutation Pm nécessaire pour déplacer le tiroir A2 vers sa position de repos sera inférieure à celle nécessaire pour maintenir le tiroir A2 dans sa position de repos, à cause de l'allongement du ressort A3, qui voit ipso facto sa force diminuer quand son allongement augmente (ressort maintenu en compression).Indeed, when the spring A3 is compressed at most by the pressure Ps, the switching pressure Pm required to move the slide A2 to its rest position will be less than that necessary to keep the slide A2 in its rest position, because the lengthening of the spring A3, which ipso facto sees its force decrease when its elongation increases (spring maintained in compression).

Cela pose des problèmes de contrôle de pression et d'ajustement du tiroir A2.This poses problems of pressure control and adjustment of the drawer A2.

Ainsi, quelles que soient les unités de pilotage S2 décrites précédemment, aucune n'est pleinement satisfaisante. La première complique et modifie grandement l'architecture de la pompe par rapport à des versions dites standard, et la deuxième présente des problèmes de contrôle.Thus, whatever the S2 control units described above, none is fully satisfactory. The former complicates and greatly modifies the architecture of the pump compared to so-called standard versions, and the second presents control problems.

PRESENTATION DE L'INVENTIONPRESENTATION OF THE INVENTION

La présente invention est définie dans les revendications indépendantes qui suivent. Des variantes préférées sont définies dans les revendications dépendantes. L'invention propose un dispositif de contrôle de cylindrée d'une machine à pistons axiaux comprenant un boitier qui loge une unité de pilotage comprenant :

  • un tiroir de pilotage de cylindrée adapté pour être commuté entre deux positions par une pression de commande selon un axe de coulissement :
    • ∘ une position de travail dans laquelle le tiroir de pilotage assure une liaison entre au moins une entrée recevant une pression d'alimentation et une sortie reliée à un vérin de réglage d'inclinaison de ladite machine, et
    • ∘ une position de repos dans laquelle le tiroir de pilotage interrompt la liaison entre ladite entrée et ladite sortie, et
  • des moyens de commutation adaptés pour faire varier la position du vérin de réglage,
  • un ressort,
dans lequel :
  • ∘ lesdits moyens de commutation comprennent un second tiroir de commutation, coaxial au tiroir de pilotage,
  • ∘ une pression de commutation exerce une force axiale sur le second tiroir en direction du tiroir de pilotage,
  • ∘ le ressort exerce une force axiale sur les deux tiroirs, qui tend à les éloigner l'un de l'autre,
  • ∘ une pression de commande exerce une force axiale sur le tiroir de pilotage en direction du second tiroir.
The present invention is defined in the following independent claims. Preferred variants are defined in the dependent claims. The invention proposes a device for controlling the displacement of an axial piston machine comprising a housing which houses a control unit comprising:
  • a displacement slide valve adapted to be switched between two positions by a control pressure along a sliding axis:
    • A working position in which the control spool ensures a connection between at least one input receiving a supply pressure and an output connected to a tilt adjustment cylinder of said machine, and
    • A rest position in which the control spool interrupts the connection between said input and said output, and
  • switching means adapted to vary the position of the adjustment jack,
  • a spring,
in which :
  • Said switching means comprise a second switching spool, coaxial with the control spool,
  • A switching pressure exerts an axial force on the second slide towards the control slide,
  • The spring exerts an axial force on the two drawers, which tends to move them away from each other,
  • A control pressure exerts an axial force on the control spool in the direction of the second spool.

L'invention peut comprendre les caractéristiques suivantes, prises seules ou en combinaison :

  • Le tiroir de pilotage comprend au moins une gorge circulaire et le tiroir possédant deux extrémités,
  • Le second tiroir comprend une tête et un corps, la tête coulissant dans un bouchon situé sur l'axe de coulissement,
  • La force axiale de la pression de commande est exercée via de l'huile par une ligne de pression de commande dans une cavité formée par le boitier et la première extrémité du piston,
  • Le ressort exerce sa force sur le corps du second tiroir et sur la deuxième extrémité du tiroir de pilotage,
  • La force axiale de la pression de commutation est exercée via de l'huile par une ligne de pression de commutation dans une cavité formée par ledit bouchon et la tête du second tiroir,
  • la deuxième extrémité du tiroir de pilotage comprend un évidement dans lequel le ressort est partiellement logé,
  • le corps du second tiroir est apte à venir au contact de la deuxième extrémité du tiroir de pilotage lorsque le ressort est comprimé à l'intérieur dudit évidement du tiroir de pilotage.
The invention may include the following features, taken alone or in combination:
  • The control spool comprises at least one circular groove and the drawer having two ends,
  • The second drawer comprises a head and a body, the head sliding in a plug located on the axis of sliding,
  • The axial force of the control pressure is exerted via oil through a control pressure line into a cavity formed by the housing and the first end of the piston,
  • The spring exerts its force on the body of the second spool and on the second end of the spool,
  • The axial force of the switching pressure is exerted via oil through a switching pressure line in a cavity formed by said plug and the head of the second slide,
  • the second end of the control spool comprises a recess in which the spring is partially housed,
  • the body of the second slide is adapted to come into contact with the second end of the control spool when the spring is compressed inside said recess of the control spool.

L'invention propose aussi une machine à pistons axiaux comprenant un dispositif selon l'une quelconque des revendications précédentes, dans lequel le boitier comprend :

  • une première entrée, une première sortie, une seconde entrée, une seconde sortie,
  • le tiroir de pilotage comprend deux gorges parallèles,
dans laquelle en position de travail, le tiroir de pilotage permet de relier la première entrée à la première sortie via la première gorge et la seconde entrée à la seconde sortie via la seconde gorge.The invention also proposes an axial piston machine comprising a device according to any preceding claim, wherein the housing comprises:
  • a first entry, a first exit, a second entry, a second exit,
  • the control spool comprises two parallel grooves,
in which in the working position, the control spool makes it possible to connect the first input to the first output via the first groove and the second input to the second output via the second groove.

L'invention peut comprendre les caractéristiques suivantes, prises seules ou en combinaison :

  • la pression de commutation est la pression d'alimentation de la machine,
  • la ligne de pression de commande comprend une restriction, de préférence un orifice de 0,5 mm de diamètre.
The invention may include the following features, taken alone or in combination:
  • the switching pressure is the supply pressure of the machine,
  • the control pressure line comprises a restriction, preferably an orifice of 0.5 mm in diameter.

Enfin, l'invention propose un procédé d'utilisation d'un dispositif ou d'une machine selon l'une quelconque des revendications précédentes, dans lequel :

  1. a. Si l'on n'applique pas de pression de commande, alors le tiroir de pilotage est maintenu en position de repos par le ressort,
  2. b. Si l'on applique une pression de commande alors le changement de cylindrée se fait automatiquement selon la charge appliquée à la machine:
    1. i. Si la force exercée par la pression de commande est supérieure à la force exercée par la pression de commutation, alors le tiroir de pilotage est en position de travail,
    2. ii. Si la force exercée par la pression de commande est inférieure à la force exercée par la pression de commutation, alors le tiroir de pilotage est en position de repos.
Finally, the invention provides a method of using a device or machine according to any one of the preceding claims, wherein:
  1. at. If no control pressure is applied, then the control spool is held in the rest position by the spring,
  2. b. If a control pressure is applied then the change of displacement is done automatically according to the load applied to the machine:
    1. i. If the force exerted by the control pressure is greater than the force exerted by the switching pressure, then the control spool is in the working position,
    2. ii. If the force exerted by the control pressure is lower than the force exerted by the switching pressure, then the control spool is in the rest position.

Le procédé peut comprendre les caractéristiques suivantes prises seules ou en combinaison :

  • le tiroir de pilotage en position de repos, respectivement de travail, signifie que la machine est à grande cylindrée, respectivement petite cylindrée,
  • la pression de commande est constante,
  • la pression de commutation est variable,
  • la pression de commande est comprise entre 20 et 40 bars,
  • la pression de commutation est comprise entre 40 et 250 bars et dépend de la charge de la machine.
The method may comprise the following features taken alone or in combination:
  • the control spool in the rest position, respectively working position, means that the machine is of large displacement, respectively small displacement,
  • the control pressure is constant,
  • the switching pressure is variable,
  • the control pressure is between 20 and 40 bar,
  • the switching pressure is between 40 and 250 bar and depends on the load of the machine.

PRESENTATION DES FIGURESPRESENTATION OF FIGURES

D'autres caractéristiques, buts et avantages de l'invention ressortiront de la description qui suit, qui est purement illustrative et non limitative, et qui doit être lue en regard des dessins annexés, sur lesquels :

  • La figure 1 présente une machine à pistons axiaux à cylindrée variable,
  • Les figures 2a, 2b présentent le plateau selon les deux états (respectivement petite et grande cylindrée),
  • La figure 3 représente un schéma hydraulique d'une machine telle qu'existant dans l'art antérieur,
  • Les figures 4a à 4c présentent respectivement une section latérale, frontale et un schéma hydraulique d'une machine telle qu'existant dans l'art antérieur,
  • La figure 4d représente une unité de pilotage conforme à l'art antérieur des figures 4a à 4c,
  • Les figures 5a, 5b, 5c, 5d présentent respectivement une section latérale, frontale et un schéma hydraulique d'une machine telle qu'existant dans l'art antérieur selon un autre mode de réalisation,
  • La figure 6 représente une unité de pilotage de l'art antérieur, selon encore un autre mode de réalisation,
  • La figure 7 présente une machine avec un dispositif conforme à un des modes de réalisation de l'invention,
  • Les figures 8 et 9 présentent une vue grossie du dispositif de l'invention dans deux positions différentes,
  • Les figures 10a, 10b présentent deux modes de réalisation de schémas hydrauliques du circuit et d'unité de contrôle des pressions,
  • Les figures 11a, 11b représentent le tiroir respectivement en position de repos et de travail.
Other characteristics, objects and advantages of the invention will emerge from the description which follows, which is purely illustrative and nonlimiting, and which should be read with reference to the appended drawings, in which:
  • The figure 1 presents an axial piston machine with variable displacement,
  • The Figures 2a , 2b present the plateau according to the two states (respectively small and large cubic capacity),
  • The figure 3 represents a hydraulic diagram of a machine as existing in the prior art,
  • The Figures 4a to 4c have respectively a lateral section, front and a hydraulic diagram of a machine as existing in the prior art,
  • The figure 4d represents a control unit according to the prior art of the Figures 4a to 4c ,
  • The Figures 5a, 5b , 5c, 5d respectively show a lateral section, front and a hydraulic diagram of a machine as existing in the prior art according to another embodiment,
  • The figure 6 represents a control unit of the prior art, according to yet another embodiment,
  • The figure 7 presents a machine with a device according to one of the embodiments of the invention,
  • The Figures 8 and 9 show an enlarged view of the device of the invention in two different positions,
  • The figures 10a , 10b present two embodiments of hydraulic diagrams of the circuit and pressure control unit,
  • The Figures 11a, 11b represent the drawer respectively in the rest and working position.

DESCRIPTION DETAILLEEDETAILED DESCRIPTION

En référence aux figures 7 , 8 , 9 et 10a , 10b , un mode de réalisation de l'invention va être décrit.With reference to figures 7 , 8 , 9 and 10a , 10b an embodiment of the invention will be described.

Le dispositif 10 est une unité de pilotage du plateau S2, intégrée à une machine à pistons axiaux 20 de cylindrées variables par inclinaison du plateau. Le dispositif 10 est un sélecteur disposé dans un circuit hydraulique 30 (voir figure 10a , 10b ), le circuit étant essentiellement similaire à celui décrit en introduction (cf. EP 2 592 263 ). Le circuit hydraulique 30 comprend une première ligne de vérin 31 et une deuxième ligne de vérin 32, reliées aux respectivement aux vérins 31a et 32a qui permettent l'inclinaison du plateau 21 en fonction des pressions auxquelles elles sont soumises.The device 10 is a control unit of the plate S2, integrated in a machine axial piston 20 of variable displacement by inclination of the plate. The device 10 is a selector disposed in a hydraulic circuit 30 (see FIG. figure 10a , 10b ), the circuit being essentially similar to that described in the introduction (cf. EP 2 592 263 ). The hydraulic circuit 30 comprises a first cylinder line 31 and a second cylinder line 32, connected respectively to the cylinders 31a and 32a which allow the inclination of the plate 21 according to the pressures to which they are subjected.

Le dispositif 1 possède deux positions : dans une position de repos, les deux lignes de vérin 31, 32 sont mises à vides, dans une position de travail, les deux lignes de vérin 31, 32 sont mises sous pression.The device 1 has two positions: in a rest position, the two cylinder lines 31, 32 are empty, in a working position, the two cylinder lines 31, 32 are pressurized.

Une première ligne d'alimentation 33 relie une unité S1 de contrôle des pressions aux pistons de la machine 20 et une deuxième ligne d'alimentation 34 relie les pistons de la machine 20 à l'unité S1. On précise que les rôles peuvent être inversés selon le sens de fonctionnement de la machine (marche avant ou marche arrière). Les lignes d'alimentation 33, 34 sont alimentées à des pressions P1, P2. Une unité S1 de contrôle des pressions répartit les pressions P1, P2 dans les lignes d'alimentation 33, 34. En fonction de l'utilisation (moteur, pompe, marche avant, marche arrière), chaque ligne 33, 34 peut amener ou récupérer l'huile, à haute ou basse pression.
Le dispositif 10 est typiquement logé dans un boitier 23 de la machine 20, le boitier comprenant une première sortie 101, une deuxième sortie 103, une première entrée 102, une deuxième entrée 104 (voir figures 11a, 11b ). La première sortie 101 du boitier 23 est reliée à la première ligne de vérin 31 et la deuxième sortie 103 est reliée à la deuxième ligne de vérin 32.
On notera que le dispositif 10 fonctionne de façon similaire avec une seule entrée et sortie au lieu des deux entrées et sorties 101, 102, 103, 104.A first supply line 33 connects a pressure control unit S1 to the pistons of the machine 20 and a second supply line 34 connects the pistons of the machine 20 to the unit S1. It is specified that the roles can be reversed depending on the direction of operation of the machine (forward or reverse). The supply lines 33, 34 are fed at pressures P1, P2. A pressure control unit S1 distributes the pressures P1, P2 in the supply lines 33, 34. Depending on the use (engine, pump, forward, reverse), each line 33, 34 can bring or recover the oil, at high or low pressure.
The device 10 is typically housed in a housing 23 of the machine 20, the housing comprising a first output 101, a second output 103, a first input 102, a second input 104 (see FIG. Figures 11a, 11b ). The first output 101 of the housing 23 is connected to the first jack line 31 and the second output 103 is connected to the second jack line 32.
Note that the device 10 operates similarly with a single input and output instead of the two inputs and outputs 101, 102, 103, 104.

Le dispositif 10 de contrôle de cylindrée d'une machine 20 à pistons axiaux comprend donc le boitier 23 qui loge une unité de pilotage S1 comprenant :

  • ∘ Un tiroir de pilotage de cylindrée 110 adapté pour être commuté entre deux positions par une pression de commande Ps selon un axe de coulissement Δ:
    • ▪ une position de repos ( figure 11a ) dans laquelle le tiroir de pilotage 110 interrompt la liaison entre ladite entrée 102, 104 et ladite sortie 101, 103, et
    • ▪ une position de travail ( figure 11b ) dans laquelle le tiroir de pilotage 110 assure une liaison entre au moins une entrée 102, 104 recevant une pression d'alimentation et une sortie 101, 103 reliée à un vérin de réglage d'inclinaison de ladite machine 31a, 31b, et
  • ∘ des moyens de commutation adaptés pour faire varier la position du vérin de réglage (31a, 31b),
  • ∘ un ressort 140.
The device 10 for controlling the displacement of an axial piston machine 20 thus comprises the housing 23 which houses a control unit S1 comprising:
  • ∘ A control slide of displacement 110 adapted to be switched between two positions by a control pressure Ps according to a sliding axis Δ:
    • ▪ a rest position ( figure 11a ) in which the control spool 110 interrupts the connection between said input 102, 104 and said output 101, 103, and
    • ▪ a working position ( figure 11b ) in which the control spool 110 provides a connection between at least one inlet 102, 104 receiving a supply pressure and an outlet 101, 103 connected to a tilt adjustment ram of said machine 31a, 31b, and
  • ∘ switching means adapted to vary the position of the adjustment ram (31a, 31b),
  • ∘ a spring 140.

Ces différents éléments sont agencés de la façon suivante :

  • ∘ lesdits moyens de commutation comprennent :
    • ▪ un second tiroir de commutation 130, coaxial au tiroir de pilotage 110,
    • ▪ une pression de commutation Pm qui exerce une force axiale sur le second tiroir 130 en direction du tiroir de pilotage 110,
  • ∘ le ressort 140 exerce une force axiale sur les deux tiroirs 110, 130 qui tend à les éloigner l'un de l'autre,
  • ∘ une pression de commande Ps exerce une force axiale sur le tiroir de pilotage 110 en direction du second tiroir 130.
These different elements are arranged as follows:
  • Said switching means comprise:
    • A second switching slide 130, coaxial with the control slide 110,
    • A switching pressure Pm which exerts an axial force on the second slide 130 in the direction of the control spool 110,
  • The spring 140 exerts an axial force on the two drawers 110, 130 which tends to move them away from each other,
  • A control pressure Ps exerts an axial force on the control spool 110 towards the second slide 130.

Plus précisément, le tiroir de pilotage 110 possède deux extrémités 110a, 110b. Le tiroir de pilotage 110 comprend au moins une gorge circulaire 111, 112, et préférablement comme mentionné précédemment une première gorge 111 qui relie la première entrée 102 à la première sortie 101 et une deuxième gorge 112 qui relie la deuxième entrée 104 à la deuxième sortie 103.More specifically, the control spool 110 has two ends 110a, 110b. The control spool 110 comprises at least one circular groove 111, 112, and preferably as mentioned above a first groove 111 which connects the first inlet 102 to the first outlet 101 and a second groove 112 which connects the second inlet 104 to the second outlet 103.

Le second tiroir 130 comprend une tête 131 et un corps 132, la tête coulissant dans un bouchon 120 situé sur l'axe de coulissement Δ.The second slide 130 comprises a head 131 and a body 132, the head sliding in a plug 120 located on the sliding axis Δ.

La force axiale de la pression de commande Ps est exercée via de l'huile par une ligne de pression de commande 105 dans une cavité formée par le boitier 23 et la première extrémité du piston 110a. Le ressort 140 exerce sa force sur le corps 132 du second tiroir 130 et sur la deuxième extrémité du tiroir de pilotage 110. Cette ligne de pression de commande 105 est typiquement de mode on/off, c'est-à-dire qu'on applique alternativement une pression Ps ou aucune pression.
La ligne de pression de commande 105 peut comprendre une restriction, de préférence un orifice de 0,5 mm de diamètre.
La force axiale de la pression de commutation Pm est exercée via de l'huile par une ligne de pression de commutation 121 dans une cavité 122 formée par ledit bouchon 120 et la tête 131 du second tiroir 130. La ligne de pression de commutation 121 se trouve dans ledit bouchon 120.The axial force of the control pressure Ps is exerted via oil through a control pressure line 105 in a cavity formed by the housing 23 and the first end of the piston 110a. The spring 140 exerts its force on the body 132 of the second slide 130 and on the second end of the control slide 110. This control pressure line 105 is typically on / off mode, that is to say that alternately applies a Ps pressure or no pressure.
The control pressure line 105 may include a restriction, preferably an orifice of 0.5 mm in diameter.
The axial force of the switching pressure Pm is exerted via oil via a switching pressure line 121 into a cavity 122 formed by said plug 120 and the head 131 of the second slide 130. The switching pressure line 121 is in said plug 120.

Dans le cas où l'on dispose de deux entrées et sorties 101, 102, 103, 104, la première ligne d'alimentation 33 est piquée par un premier prélèvement 33a pour alimenter la première entrée 102 et la deuxième ligne d'alimentation 34 est piquée par deuxième prélèvement 34a pour alimenter la deuxième entrée 104.In the case where two inputs and outputs 101, 102, 103, 104 are available, the first supply line 33 is stitched by a first sample 33a to feed the first input 102 and the second supply line 34 is stitched by second sample 34a to feed the second input 104.

Le boitier 23 guide le tiroir de pilotage 110. La première extrémité 110a du tiroir de pilotage 110 et le boitier 23 forment une cavité 113, de taille variable selon la position du tiroir de pilotage 110. La ligne de pression de déplacement 105 alimente ladite cavité 113 en huile sous pression de commande Ps. Préférablement, lorsque le mode automatique est activé, la pression de commande Ps est constante. De plus, elle est typiquement comprise entre 20 et 40 bars. De cette façon, le dispositif 10 est tel que l'huile sous pression exerce une force de déplacement Fd sur le tiroir de pilotage 110 selon l'axe de coulissement Δ, en direction du second tiroir 130.
Alternativement, la pression Ps est réglable par l'utilisateur pour paramétrer le fonctionnement de la machine.
Comme mentionné précédemment, la communication entre les entrées 102, 104 et sorties 101, 103 respectivement se fait par les deux gorges circulaires 111, 112 (voir figures 8, 9 et 11a pour la position de repos, et figure 11b pour la position de travail - seule la gorge 111 est présentée) dessinées sur le tiroir de pilotage 110 lorsque la cavité 113 est soumise à la pression de commande Ps. Ces gorges 111, 112 ont aussi une fonction de limiteur de débit.The housing 23 guides the control spool 110. The first end 110a of the control spool 110 and the housing 23 form a cavity 113, of variable size according to the position of the control spool 110. The displacement pressure line 105 supplies said cavity 113 in pressure control oil Ps. Preferably, when the automatic mode is activated, the control pressure Ps is constant. In addition, it is typically between 20 and 40 bar. In this way, the device 10 is such that the pressurized oil exerts a displacement force Fd on the control spool 110 according to the sliding axis Δ, towards the second slide 130.
Alternatively, the pressure Ps is adjustable by the user to set the operation of the machine.
As mentioned above, the communication between the inputs 102, 104 and outputs 101, 103 respectively is via the two circular grooves 111, 112 (see FIG. Figures 8, 9 and 11a for the rest position, and figure 11b for the working position - only the groove 111 is shown) drawn on the control spool 110 when the cavity 113 is subjected to the control pressure Ps. These grooves 111, 112 also have a flow restrictor function.

Le second tiroir 130 coulisse dans le bouchon 120 selon l'axe de coulissement Δ, ce qui signifie que les déplacements du tiroir de pilotage 110 et du second tiroir 130 sont colinéaires. Le bouchon 120 guide ainsi le second tiroir 130. La tête 131 et le bouchon 120 forme une cavité 122, de taille variable selon la position du second tiroir 130. La ligne de pression de commutation 121 alimente ladite cavité 122 en huile sous pression de commutation Pm. La pression de commutation Pm correspond typiquement à l'une des pressions P1, P2 d'alimentation de la machine 20. Elle est donc variable en fonction de la charge de la machine 20. Elle est comprise typiquement entre 40 et 250 bars.
De cette façon, le dispositif 10 est tel que l'huile sous pression de commutation Pm dans la cavité 122 exerce une contre-force Fc sur la tête 131 du second tiroir 130 selon l'axe de coulissement Δ, en direction du tiroir de pilotage 110.The second slide 130 slides in the plug 120 along the sliding axis Δ, which means that the movements of the control spool 110 and the second spool 130 are collinear. The plug 120 thus guides the second slide 130. The head 131 and the plug 120 form a cavity 122, of variable size according to the position of the second slide 130. The switching pressure line 121 supplies said cavity 122 oil under pressure switching Pm. The switching pressure Pm typically corresponds to one of the pressures P1, P2 for supplying the machine 20. It is therefore variable as a function of the load of the machine 20. It is typically between 40 and 250 bar.
In this way, the device 10 is such that the pressurized switching oil Pm in the cavity 122 exerts a counter-force Fc on the head 131 of the second slide 130 according to the sliding axis Δ, in the direction of the control spool 110.

Le ressort 140, comme mentionné précédemment, est situé entre la deuxième extrémité 110b du tiroir de pilotage 110 et le corps 132 du second tiroir 130. Par l'architecture du dispositif 10, le ressort 140 exerce des forces de poussée (il est en permanence en compression).
Le ressort 140 baigne dans l'huile. Pour cela, un circuit de drainage 150 permet d'alimenter en huile la zone du ressort 140.The spring 140, as mentioned above, is located between the second end 110b of the control spool 110 and the body 132 of the second spool 130. By the architecture of the device 10, the spring 140 exerts thrust forces (it is constantly in compression).
The spring 140 is immersed in the oil. For this purpose, a drainage circuit 150 makes it possible to supply the area of the spring 140 with oil.

Selon un mode de réalisation préféré, la deuxième extrémité 110b du tiroir de pilotage 110 comprend un évidement 114 dans lequel est logé partiellement le ressort 140 (voir figures 8 et 9 en particulier). En outre, le corps 132 du second tiroir 130 est apte à venir au contact de la deuxième extrémité 110b lorsque le ressort 140 est comprimé à l'intérieur dudit évidement 114 du tiroir de pilotage 110. Pour cela, le diamètre du corps 132 du second tiroir 130 est par exemple égal ou supérieur au diamètre de la deuxième extrémité 110b.
Le circuit de drainage 150 débouche dans l'évidement 114.According to a preferred embodiment, the second end 110b of the control spool 110 comprises a recess 114 in which the spring 140 is partially housed (see FIG. Figures 8 and 9 in particular). In addition, the body 132 of the second slide 130 is adapted to come into contact with the second end 110b when the spring 140 is compressed inside said recess 114 of the control spool 110. For this, the diameter of the body 132 of the second drawer 130 is for example equal to or greater than the diameter of the second end 110b.
The drainage circuit 150 opens into the recess 114.

Sauf donc en butée, la deuxième extrémité 110b du tiroir de pilotage 110 n'est donc pas en contact direct avec le second tiroir 130.Except therefore in abutment, the second end 110b of the control slide 110 is not in direct contact with the second slide 130.

Alternativement (non représenté sur les figures), la deuxième extrémité 110b du tiroir de pilotage 110 ne peut venir au contact du corps 132 du second tiroir 130 : soit le ressort ayant une raideur telle que la force de déplacement Fd et la contre-force Fc ne peuvent le comprimer assez, soit parce que son volume de matière empêche le contact lorsqu'il est intégralement comprimé.Alternatively (not shown in the figures), the second end 110b of the control slide 110 can not come into contact with the body 132 of the second slide 130: either the spring having a stiffness such that the displacement force Fd and the counterforce Fc can compress enough, or because its volume of material prevents contact when fully compressed.

La force de déplacement Fd est égale au produit de la pression de commande Ps de l'huile dans la ligne de pression de déplacement 105 avec l'aire St de la section sur laquelle la pression de commande Ps s'exerce, c'est-à-dire typiquement la section de la première extrémité 110a du tiroir 110 : Fd = Ps x St.
Similairement, la contre-force Fc est égale au produit de la pression de commutation Pm de l'huile dans la ligne de pression de commutation 121 avec l'aire Sp de la section sur laquelle la pression de commande Ps s'exerce, c'est-à-dire la section de la tête 131 de second tiroir 130 : Fc = Pm x Sp.
Par l'agencement des éléments décrits précédemment, on rappelle que la force de déplacement Fd et la contre-force Fc s'exercent donc en sens contraire.
Le ressort 140, quant à lui, s'oppose aux déplacements du tiroir de pilotage 110 et du second tiroir 130. A second tiroir 130 fixe, le ressort exerce donc sa force d'opposition Fo (ladite force étant égale au produit de sa raideur et de sa différence de longueur avec sa longueur à vide) en sens contraire à celui de la force de déplacement Fd. A tiroir de pilotage 110 fixe, le ressort 140 exerce donc sa force d'opposition Fo en sens contraire à celui de la contre-force Fc.
A toutes fins utiles, on rappelle la force d'opposition du ressort Fo sur une pièce dépend de la position de la pièce située de l'autre côté, puisque cette position a une influence sur la longueur du ressort 140 comprimé.The displacement force Fd is equal to the product of the control pressure Ps of the oil in the displacement pressure line 105 with the area St of the section on which the control pressure Ps is exerted, that is, that is, typically the section of the first end 110a of the drawer 110: Fd = Ps x St.
Similarly, the counter-force Fc is equal to the product of the switching pressure Pm of the oil in the switching pressure line 121 with the area Sp of the section on which the control pressure Ps is exerted. that is, the section of the second drawer head 130 130: Fc = Pm x Sp.
By the arrangement of the elements described above, it is recalled that the displacement force Fd and the counter force Fc are therefore exerted in the opposite direction.
The spring 140, for its part, opposes the movements of the control spool 110 and the second spool 130. A second fixed spool 130, the spring therefore exerts its opposing force Fo (said force being equal to the product of its stiffness and its difference in length with its empty length) in opposite direction to that of the displacement force Fd. A fixed control spool 110, the spring 140 thus exerts its opposing force Fo in opposite direction to that of the counter force Fc.
For all practical purposes, it is recalled that the opposing force of the spring Fo on a part depends on the position of the part situated on the other side, since this position has an influence on the length of the compressed spring 140.

La raideur du ressort 140 et/ou la pression de commande Ps est choisie (en fonction de la surface active de la partie mobile) de sorte que la valeur de la force d'opposition Fo minimale est inférieure la force de déplacement Fd.
Lorsque le second tiroir 130 est en butée dans le bouchon 120, c'est-à-dire que la cavité 122 du bouchon 120 est de taille minimale, et que la ligne de pression de déplacement 105 n'alimente pas la cavité 113 en huile sous pression de commande Ps, le ressort 140 maintient le tiroir de pilotage 110 en position de repos (c'est-à-dire que la cavité 113 du boitier 23 est de taille minimale).
Plus généralement, quelles que soient les positions du tiroir de pilotage 110 et du second tiroir 130, tant que la force de déplacement Fd est inférieure à la force d'opposition Fo, le tiroir de pilotage 110 est maintenu en position de repos par le ressort 140, comme peut l'illustrer la figure 8 .
On remarquera que si est la cavité 122 du bouchon 120 est à pression de commutation Pm, le tiroir de pilotage 110 est a fortiori maintenu dans cette position de repos, comme peut l'illustrer la figure 9 .
En revanche, lorsque la cavité 113 est alimentée en huile sous pression de commande Ps, le tiroir de pilotage 110 peut être mis dans les deux positions sans que la longueur du ressort 140 ne change. Pour cela, la pression de commande Ps doit pouvoir générer une force de déplacement Fd supérieure à la force d'opposition Fo maximale, qui est celle obtenue lorsque la cavité 122 a un volume maximal, qui est celle du ressort le plus fortement comprimé.
On obtient deux cas :

  • ▪ Si la force de déplacement Fd est supérieure à la contre-force Fc, alors le tiroir de pilotage 110 est en position de travail,
  • ▪ Si la force de déplacement Fd est inférieure à la contre-force Fc, alors le tiroir de pilotage 110 est en position de repos,
On va détailler à présent plus précisément l'état du ressort 140 dans ces cas.The stiffness of the spring 140 and / or the control pressure Ps is chosen (as a function of the active surface of the moving part) so that the value of the minimum opposition force Fo is lower than the displacement force Fd.
When the second slide 130 is in abutment in the plug 120, that is to say that the cavity 122 of the plug 120 is of minimum size, and the displacement pressure line 105 does not feed the cavity 113 in oil under control pressure Ps, the spring 140 keeps the control spool 110 in the rest position (that is to say that the cavity 113 of the housing 23 is of minimum size).
More generally, regardless of the positions of the control spool 110 and the second spool 130, as long as the displacement force Fd is less than the opposing force Fo, the spool 110 is held in the rest position by the spring 140, as can be illustrated by figure 8 .
It will be noted that if the cavity 122 of the plug 120 is at a switching pressure Pm, the control spool 110 is a fortiori maintained in this rest position, as can be illustrated by FIG. figure 9 .
On the other hand, when the cavity 113 is fed with pressurized control oil Ps, the control spool 110 can be put in the two positions without the length of the spring 140 changing. For this, the control pressure Ps must be able to generate a displacement force Fd greater than the maximum opposition force Fo, which is the one obtained when the cavity 122 has a maximum volume, which is that of the most strongly compressed spring.
We obtain two cases:
  • ▪ If the displacement force Fd is greater than the counter force Fc, then the control spool 110 is in the working position,
  • ▪ If the displacement force Fd is lower than the counter force Fc, then the control spool 110 is in the rest position,
We will now detail more precisely the state of the spring 140 in these cases.

Selon un premier mode de réalisation (préféré) du ressort 140 et de la deuxième extrémité 110b du tiroir de pilotage 110 : on suppose le tiroir de pilotage 110 en position de travail, c'est-à-dire que que Fd>Fo, on applique ensuite Fc sur le second tiroir, avec Fc > Fo. Dans ce cas, le ressort 140 va se comprimer jusqu'à ce que le corps 132 du second tiroir 130 soit au contact de la deuxième extrémité 110b du tiroir de pilotage 110. Il s'agit ensuite de deux pièces solides en contact, et le déplacement se fait dans un sens ou dans l'autre selon la valeur des forces : les caractéristiques des différents éléments (la pression de contrôle Ps, la raideur du ressort 140, choix des surfaces, etc.) sont choisies lors de la conception de sorte que Fc puisse être supérieure à Fd, de cette façon le tiroir de pilotage 110 passe en position de repos. Inversement, le tiroir 110 repasse en position de travail, lorsque la pression de commutation Pm diminue et vérifie Fc<Fd. La diminution de la pression de commutation Pm est liée à la charge de la machine 20 (montée, descente, utilisation intense, etc.).According to a first (preferred) embodiment of the spring 140 and the second end 110b of the control spool 110: the control spool 110 is assumed to be in the working position, that is to say that Fd> Fo, on then applies Fc to the second drawer, with Fc> Fo. In this case, the spring 140 will compress until the body 132 of the second slide 130 is in contact with the second end 110b of the control spool 110. This is then two solid parts in contact, and the displacement is done in one direction or the other depending on the value of the forces: the characteristics of the various elements (the control pressure Ps, the stiffness of the spring 140, choice of surfaces, etc.) are chosen during the design so that Fc can be greater than Fd, in this way the control spool 110 passes into the rest position. Conversely, the drawer 110 returns to the working position, when the switching pressure Pm decreases and Fc <Fd checks. The decrease of the switching pressure Pm is related to the load of the machine 20 (rise, fall, intense use, etc.).

Selon un autre mode de réalisation du ressort 140 : on suppose le tiroir de pilotage 110 en position de travail, c'est-à-dire que que Fd>Fo, on applique ensuite Fc sur le second tiroir, avec Fc > Fo. Dans ce cas, le ressort 140 va se comprimer jusqu'à ce que Fo=Fc (ou bien atteindre sa limite mécanique, c'est-à-dire sa compression physique maximale, et dans ce cas le ressort se comporte comme une pièce solide et on a aussi Fo=Fc). Les caractéristiques des différents éléments (la pression de contrôle Ps, raideur du ressort 140, choix des surfaces etc.) sont choisies lors de la conception de sorte de sorte que Fc (alors égale à Fo) puisse être supérieure à Fd, de cette façon, on a Fc=Fo>Fd, et donc le tiroir de pilotage 110 passe en position repos. Inversement, le tiroir 110 repasse en position de travail lorsque la pression de commutation Pm diminue et vérifie Fc=Fo<Fd.According to another embodiment of the spring 140: it assumes the control spool 110 in the working position, that is to say that Fd> Fo, then applies Fc on the second drawer, with Fc> Fo. In this case, the spring 140 will compress until Fo = Fc (or reach its mechanical limit, that is to say its maximum physical compression, and in this case the spring behaves like a solid piece and we also have Fo = Fc). The characteristics of the various elements (the control pressure Ps, stiffness of the spring 140, choice of surfaces, etc.) are chosen during the design so that Fc (then equal to Fo) can be greater than Fd, in this way Fc = Fo> Fd, and thus the control spool 110 goes into the rest position. Conversely, the spool 110 returns to the working position when the switching pressure Pm decreases and checks Fc = Fo <Fd.

Dans les deux cas par conséquent, lorsque le mode automatique est activé (i.e. la ligne 105 est mise à la pression Ps, ce qui permet d'activer Fd qui s'oppose à Fc), le pilotage du tiroir de pilotage 110 est piloté par la valeur algébrique Fd-Fc, et la valeur de la force Fo du ressort 130 n'intervient plus, contrairement à l'art antérieur de Kayaba décrit en introduction.
Plus concrètement, l'ajout d'un second tiroir 120 signifie que le ressort exerce sa force de chaque côté sur un tiroir différent qui chacun est mobile et déplacé par de la pression d'huile. Par conséquent, les deux forces de sens contraire exercées par le ressort se compensent.
On obtient, dans un même dispositif compact et structurellement proche des solutions sans mode automatique, un dispositif avec mode non-automatique qui profite pleinement du ressort pour maintenir le dispositif 10 en position de repos et un mode automatique qui permet de s'affranchir du ressort afin de pouvoir commuter entre la position de repos et la position de travail en fonction uniquement des pressions de commande Ps et de commutation Pm.In both cases therefore, when the automatic mode is activated (ie the line 105 is put under the pressure Ps, which makes it possible to activate Fd that opposes Fc), the control spool 110 is controlled by the algebraic value Fd-Fc, and the value of the force Fo of the spring 130 is no longer involved, unlike the prior art of Kayaba described in introduction.
More concretely, the addition of a second slide 120 means that the spring exerts its force on each side on a different slide which is each movable and displaced by oil pressure. Consequently, the two counter-forces exerted by the spring counterbalance each other.
In a same compact device and structurally close solutions without automatic mode, a device with non-automatic mode that takes full advantage of the spring to maintain the device 10 in the rest position and an automatic mode that eliminates the spring in order to be able to switch between the rest position and the working position depending solely on the control pressure Ps and Pm switching.

En relation avec le circuit hydraulique 30, lorsque le dispositif 10 est en position de travail, le premier prélèvement 33a est relié à la première ligne de vérin 31 par la première entrée 102, la gorge 111 et la sortie haute pression 101, pour permettre l'activation du vérin 31a.
Dans la position de repos, les lignes de vérins 31, 32 ne sont plus alimentées en huile sous pression. Dans cette position, les lignes de vérins 31, 32 sont toutes les deux reliées à une ligne de mise à vide.
En position de repos, respectivement de travail, la machine 20 est dite à grande cylindrée, respectivement petite cylindrée.In connection with the hydraulic circuit 30, when the device 10 is in the working position, the first sample 33a is connected to the first cylinder line 31 by the first inlet 102, the groove 111 and the high pressure outlet 101, to enable the activation of the cylinder 31a.
In the rest position, the cylinder lines 31, 32 are no longer supplied with oil under pressure. In this position, the lines of cylinders 31, 32 are both connected to a line of emptiness.
In the rest position, respectively working, the machine 20 is said to have large displacement, respectively small displacement.

Lorsque le mode automatique est activé (i.e. la ligne 105 est mise sous pression Ps) :

  • en utilisation nulle ou de faible intensité, les lignes d'alimentation 33, 34 de la machine 20 sont faiblement chargées et la pression de commutation Pm, qui est l'une des pressions d'alimentation P1, P2 de la machine 20, est faible. De cette façon, le tiroir 110 est en position de travail et les lignes d'alimentation de vérins 31, 32 sont alimentés en huile sous pression. La machine est alors en petite cylindrée,
  • en utilisation de forte intensité, les lignes d'alimentation 33, 34 de la machine 20 sont fortement chargées et la pression Pm est élevée. De cette façon, le tiroir 110 est poussé en position de repos et les lignes 31, 32 ne sont plus alimentés en huile sous pression et sont mises à vide vers le réservoir. Le moteur est alors en grande cylindrée.
When the automatic mode is activated (ie line 105 is pressurized Ps):
  • in zero or low intensity use, the supply lines 33, 34 of the machine 20 are lightly charged and the switching pressure Pm, which is one of the supply pressures P1, P2 of the machine 20, is low . In this way, the drawer 110 is in the position of work and supply lines of cylinders 31, 32 are fed with oil under pressure. The machine is then in small displacement,
  • in high intensity use, the supply lines 33, 34 of the machine 20 are heavily loaded and the pressure Pm is high. In this way, the drawer 110 is pushed into the rest position and the lines 31, 32 are no longer supplied with pressurized oil and are evacuated to the reservoir. The engine is then in large displacement.

Deux modes de réalisation de l'unité S1 sont à présent donnés.
Dans un premier mode de réalisation ( figure 10a ), l'unité S1 comprend un distributeur 40 cinq ports, trois positions. Le distributeur 40 reçoit les lignes d'alimentation 33, 34 ainsi que la ligne de pression de contrôle Pm. Ce distributeur 40 permet soit :

  • dans une position à vide, d'applique la pression P1 dans la première ligne d'alimentation 33 et la pression P2 dans la deuxième ligne d'alimentation 34 dans une position, la première ligne d'alimentation 33 et la ligne de pression de commutation 121 sont mises à la pression P1, la deuxième ligne d'alimentation 34 servant alors de refoulement pour la machine hydraulique 20,
  • dans une autre position, la seconde ligne d'alimentation 34 et la ligne de pression de commutation 121 sont mises à la pression P2, la première ligne d'alimentation 33 servant alors de refoulement.
Le distributeur 40 intègre des clapets anti-retour 41 en direction des lignes d'alimentation 33, 34 de la machine 20.
Dans ce mode de réalisation, le circuit 30 peut comprendre au moins deux limiteurs de pressions 36 entre les deux lignes d'alimentation 33, 34, dans deux sens différents.Two embodiments of the unit S1 are now given.
In a first embodiment ( figure 10a ), the unit S1 comprises a distributor 40 five ports, three positions. The distributor 40 receives the supply lines 33, 34 and the control pressure line Pm. This distributor 40 allows either:
  • in a vacuum position, applies the pressure P1 in the first supply line 33 and the pressure P2 in the second supply line 34 in a position, the first supply line 33 and the switching pressure line 121 are put at the pressure P1, the second supply line 34 then serving as discharge for the hydraulic machine 20,
  • in another position, the second supply line 34 and the switching pressure line 121 are put under the pressure P2, the first supply line 33 then serving as discharge.
The distributor 40 incorporates check valves 41 towards the supply lines 33, 34 of the machine 20.
In this embodiment, the circuit 30 may comprise at least two pressure limiters 36 between the two supply lines 33, 34, in two different directions.

Dans un deuxième mode de réalisation ( figure 10b ) l'unité S1 comprend un distributeur 42 six ports, cinq positions. Les lignes d'alimentation 33, 34 sont divisées et sont chacune reliée à deux ports du distributeur 42.In a second embodiment ( figure 10b ) the unit S1 comprises a distributor 42 six ports, five positions. The supply lines 33, 34 are divided and are each connected to two ports of the distributor 42.

Trois des positions sont similaires en fonction au distributeur 40 précédent.
A l'exception de la ligne de commutation 121, le document EP 2 592 263 décrit une cette unité S1.
Dans les deux positions supplémentaires :

  • le distributeur 42 relie un des deux ports de la première ligne d'alimentation 33 à la pression P1 (avec un clapet anti-retour 41) et un deux ports de la deuxième ligne d'alimentation 34 à la pression P1 aussi, avec un limiteur de débit, ou
  • le distributeur 42 relie l'autre des deux ports de la seconde ligne d'alimentation 34 à la pression P2 (avec un clapet anti-retour 41) et l'autre des deux ports de la première ligne d'alimentation 34 à la pression P2, avec un limiteur de débit.
Three of the positions are similar depending on the previous distributor 40.
With the exception of the switching line 121, the document EP 2 592 263 describes this unit S1.
In the two additional positions:
  • the distributor 42 connects one of the two ports of the first supply line 33 to the pressure P1 (with a nonreturn valve 41) and a second port of the second supply line 34 to the pressure P1 too, with a limiter debit, or
  • the distributor 42 connects the other of the two ports of the second supply line 34 to the pressure P2 (with a non-return valve 41) and the other of the two ports of the first supply line 34 to the pressure P2 , with a flow limiter.

En comparant l'architecture du dispositif 10 par rapport à la solution de l'art antérieur sans mode automatique ( figure 4d vs. figure 8 ), on remarque que l'architecture reste semblable, à l'inverse du premier art antérieur décrit (différents éléments dans plusieurs plans, cf. figures 5a à 5c ). En effet, le tiroir de pilotage 110, le ressort 140, l'arrivée de la ligne de pression de déplacement 105, le boîtier 23 côté premier extrémité 11a du tiroir de pilotage 110 sont inchangés. Le bouchon 120 et le second tiroir 130 sont quant à eux nouveaux mais sont adaptables sur des éléments standards.
Enfin, en ce qui concerne le boitier 23 de la machine 20, celui-ci nécessite simplement une modification aux environs du bouchon 120 et du second tiroir 130.Comparing the architecture of the device 10 with the solution of the prior art without automatic mode ( figure 4d vs. figure 8 ), we note that the architecture remains similar, unlike the first described prior art (different elements in several planes, cf. Figures 5a to 5c ). Indeed, the control spool 110, the spring 140, the arrival of the displacement pressure line 105, the casing 23 on the first end side 11a of the control spool 110 are unchanged. The plug 120 and the second drawer 130 are new but are adaptable to standard elements.
Finally, as regards the housing 23 of the machine 20, it simply requires a modification in the vicinity of the plug 120 and the second slide 130.

Claims (12)

  1. A device (10) for controlling the displacement of a machine (20) with axial pistons comprising a case (23) that houses a control unit comprising:
    ∘ a displacement control spool (110) adapted to be switched between two positions by a control pressure (Ps) according to an axis of sliding (Δ):
    ▪ a working position in which the control spool (110) provides a connection between at least one inlet (102, 104) that receives a supply pressure and an outlet (101, 103) connected to a cylinder for adjusting the inclination of said machine (31a, 31b), and
    ▪ an idle position in which the control spool (110) interrupts the connection between said inlet (102, 104) and said outlet (101, 103), and
    ∘ means for switching adapted to vary the position of the adjusting cylinder (31a, 31b),
    ∘ a spring (140),
    ∘ said means of communication comprise a second switching spool (130), coaxial to the control spool (110),
    ∘ a switching pressure (Pm) exerts an axial force on the second spool (130) in the direction of the control spool (110),
    ∘ a control pressure (Ps) exerts an axial force on the control spool (110) in the direction of the second spool (130),
    characterized in that:
    ∘ the spring (140) exerts an axial force on the two spools (110, 130), which tends to move them apart from each other.
  2. The device according to claim 1, wherein
    ∘ the control spool (110) comprises at least one circular groove (111, 112) and the spool having two ends (110a, 110b),
    ∘ the second spool (130) comprises a head (131) and a body (132), with the head sliding in a plug (120) located on the axis of sliding (Δ),
    ∘ the axial force of the control pressure (Ps) is exerted via oil by a control pressure line (105) in a cavity formed by the case (23) and the first end of the piston (110a),
    ∘ the spring (140) exerts its force on the body (132) of the second spool (130) and on the second end of the control spool (110),
    ∘ the axial force of the switching pressure (Pm) is exerted via oil by a switching pressure line (121) in a cavity (122) formed by said plug (120) and the head (131) of the second spool (130).
  3. The device according to any one of the preceding claims, wherein the second end (110b) of the control spool (110) comprises a recess (114) wherein the spring (140) is partially housed.
  4. The device according to the preceding claim, wherein the body (132) of the second spool (130) is able to come into contact with the second end (110b) of the control spool (110) when the spring (140) is compressed inside said recess (114) of the control spool (110).
  5. A machine with axial pistons comprising a device according to any one of the preceding claims, wherein the case comprises:
    ∘ a first inlet (102),
    ∘ a first outlet (101),
    ∘ a second inlet (104),
    ∘ a second outlet (103),
    and the control spool (110) comprises two parallel grooves (111, 112), wherein in working position, the control spool (110) makes it possible to connect the first inlet (102) to the first outlet (101) via the first groove (111) and the second inlet (104) to the second outlet (103) via the second groove (112).
  6. The machine with axial pistons according to the preceding claim characterized in that the switching pressure (Pm) is the supply pressure (P1, P2) of the machine.
  7. The machine with axial pistons according to one of claims 5 or 6 characterized in that the control pressure line (105) comprises a restriction, preferably an orifice of 0.5 mm in diameter.
  8. A method for using a device or a machine according to any one of the preceding claims, wherein:
    a. if no control pressure (Ps) is applied, then the control spool (110) is maintained in idle position by the spring (140),
    b. if a control pressure (Ps) is applied then the change in displacement is automatically carried out according to the load applied to the machine (20) :
    i. if the force exerted by the control pressure (Ps) is greater than the force exerted by the switching pressure (Pm), then the control spool (110) is in working position,
    ii. if the force exerted by the control pressure (Ps) is less than the force exerted by the switching pressure (Pm), then the control spool (110) is in idle position.
  9. The method for using according to the preceding claim, wherein when the control spool (110) is in idle, respectively working, position, the machine (20) has a large displacement, respectively small displacement.
  10. The method for using according to one of claims 8 to 9, wherein the control pressure (Ps) is constant.
  11. The method for using according to one of claims 8 to 10 wherein the switching pressure (Pm) is variable.
  12. The method for using according to one of claims 8 to 11, wherein:
    ∘ the control pressure (Ps) is between 20 and 40 bars.
    ∘ the switching pressure (Pm) is between 40 and 250 bars and depends on the load of the machine (20).
EP15201484.1A 2014-12-23 2015-12-21 Device for automatically switching the displacement of an axial piston machine Active EP3037661B1 (en)

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Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107587940B (en) * 2017-10-24 2023-07-18 青岛大学 Hydraulic transmission engine without crankshaft
CN111412191B (en) * 2019-06-05 2021-10-08 浙江厚达智能科技股份有限公司 Actuating mechanism for traditional Chinese medicine production
CN110075988B (en) * 2019-06-05 2020-12-29 浙江厚达智能科技股份有限公司 Traditional Chinese medicine mashing mechanism
CN117100392B (en) * 2023-10-24 2024-02-13 江苏若尧医疗装备有限公司 Clamping device and application thereof in surgical robot arm

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH075281Y2 (en) * 1987-10-09 1995-02-08 日立建機株式会社 Hydraulic motor capacity controller
JP2654953B2 (en) * 1987-10-27 1997-09-17 カヤバ工業株式会社 Control device for 2-speed motor
JPH08219004A (en) * 1995-02-08 1996-08-27 Hitachi Constr Mach Co Ltd Capacity control device of hydraulic rotary machine
JP3603007B2 (en) * 2000-05-10 2004-12-15 株式会社カワサキプレシジョンマシナリ Variable displacement hydraulic motor displacement control device
JP4444620B2 (en) * 2003-10-15 2010-03-31 ナブテスコ株式会社 Automatic transmission mechanism of hydraulic motor
ITMO20060122A1 (en) 2006-04-12 2007-10-13 Comer Ind Spa HYDRAULIC AXIAL PISTON ENGINE
JP5571350B2 (en) * 2009-10-19 2014-08-13 カヤバ工業株式会社 Hydraulic motor drive device
JP5256545B2 (en) * 2010-02-10 2013-08-07 Ｓｍｃ株式会社 Pressure reducing switching valve
EP2592263B1 (en) 2011-11-09 2017-12-20 Poclain Hydraulics Industriale S.R.L. Hydraulic actuation unit, particularly for controlling the starting and stopping of hydraulic motors
DE102012022997A1 (en) * 2012-11-24 2014-05-28 Robert Bosch Gmbh Adjustment device for a hydraulic machine and hydraulic axial piston machine
JP6111116B2 (en) * 2013-03-28 2017-04-05 Ｋｙｂ株式会社 Pump volume control device

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

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Publication number Publication date
FR3030641A1 (en) 2016-06-24
US10428788B2 (en) 2019-10-01
CN105715616B (en) 2020-06-26
US20160177913A1 (en) 2016-06-23
FR3030641B1 (en) 2017-01-13
EP3037661A1 (en) 2016-06-29
CN105715616A (en) 2016-06-29

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