FR3048467A1 - HYDRAULIC REMOTE CONTROL FOR HYDRAULIC DOUBLE-EFFECT ACTUATOR - Google Patents

Abstract

Remote control comprising a distributor (12) having a neutral segment (S1), two active segments (S2, S3), a floating segment (S4), two hydraulic control chambers (122, 562), a stop (515) for the movement of the slide (121), separating the range of movement of the slide (121) of the segments (S2, S3) and its floating segment (S4). A hydraulic handle (11) controls the spool (121) fed by a regulated hydraulic pressure (P2) and outputting a reduced regulated pressure (P3) supplying either one of the control chambers (122, 562). A hydraulic locking device (5) having a hydraulic switch (52) independently controlled by the hydraulic handle (11) alternately feeds one or the other chamber (122, 562) with hydraulic fluid at the controlled pressure (P2) sufficient to pass the stop (515).

Description

Field of the invention

The present invention relates to a hydraulic remote control for a double acting hydraulic actuator.

State of the art

Many forms of hydraulic remote control are known.

In general, for a double-acting actuator such as a double-acting cylinder which is connected to the hydraulic circuit of the pump and to the tarpaulin for the return, the distributor has a drawer with a neutral segment which blocks the two chambers of the actuator and the arrival and the exit of hydraulic liquid with respect to the pump and the cover; on either side of this neutral segment or neutral position, there are two active segments (or active positions) which make it possible to feed one or the other of the two chambers of the jack to push it in one direction or the other.

But it is essential that the actuator can also be placed in floating position, that is to say in a position allowing the piston of the actuator to be moved freely without compression of the hydraulic fluid in one or in the another room. This so-called floating position is obtained with the aid of a fourth segment of the spool valve which puts the two chambers in communication with the tarpaulin. In the current remote controls, we arrive in this position by moving the drawer with the remote control. But depending on the case, this floating position is not locked, so it is necessary to keep the drawer in this position with the handle, or that this position is locked mechanically by mechanically operating the drawer with the control handle.

But this locked position lacks security because it is sufficient to maneuver the lever to pull the drawer mechanically and thus move into an active position.

This situation is dangerous if an operator intervenes on the actuator or the drive train connected to the actuator. This is for example an actuator that controls a tool on a hoist or a public works machine. In the event of a tool change, the actuator must be placed in a floating position to bring the two parts to be connected between the boom of the machine and the tool (for example a bucket or other equipment) and put in place the pin. or the axis connecting the equipment to the arrow of the machine.

If during such a tool change operation, the lever is accidentally controlled and leaves its floating position, the cylinder deploys or retracts and may cause an accident.

Purpose of the invention

The present invention aims to develop a hydraulic remote control for hydraulically controlling the slide valve connected to the actuator and for hydraulically locking the floating position.

DESCRIPTION AND ADVANTAGES OF THE INVENTION For this purpose, the subject of the present invention is a remote control characterized in that it comprises: A. a spool valve connecting the pump and the cover to the actuator, the drawer having, on the one hand, and other, a neutral segment, two active actuator control segments and beyond these actuator control segments and beyond these segments, a floating segment, two control chambers hydraulic means for controlling the spool in both directions, a stop for the movement of the spool, separating the range of movement of the spool comprising the control segments and its floating segment, B. a hydraulic lever for controlling the spool in both directions by the two control chambers, the hydraulic lever being fed by a regulated hydraulic pressure lower than the outlet pressure of the pump and outputting a reduced regulated pressure supplying the one or the other control chamber, this pressure being lower than the regulated pressure, the reduced regulated pressure being sufficient to generate a thrust to move the slide and activate one or the other of these active segments from the neutral segment, but insufficient to generate a thrust allowing the slide to pass the stop, C. a hydraulic locking device comprising a hydraulic switch controlled independently of the hydraulic lever to alternately supply one or the other of the two chambers with hydraulic fluid at the pressure regulated, to generate a thrust on the drawer, sufficient to pass the stop.

The remote control according to the invention has the advantage of completely separating the hydraulic control lever from the dispenser and the means for locking or unlocking the dispenser in its floating position. Locking or unlocking requires a different manual intervention from an action on the joystick so that this intervention can not be accidental or unintentional.

In addition, the switch can be positioned so as not to be simply accessible to prevent an involuntary gesture from operating the switch in one direction or the other.

The remote control according to the invention thus offers the advantage of a very high security of the locking of the floating position of the dispenser.

According to another advantageous characteristic, the hydraulic locking device comprises two selectors and each selector is connected at the output to the hydraulic connection of one of the control chambers and at the input to one of the outputs of the hydraulic switch and to one outputs of the hydraulic lever, the other selector being connected at the output to the other control chamber and input, to the other output of the hydraulic switch and the hydraulic lever for supplying regulated pressure to one or the other other control rooms.

This solution has the advantage of simplifying the hydraulic circuits connected to the control chambers of the spool valve since the same hydraulic connection is used both to actuate the spool and to move it to its normal operating positions (neutral position, positions active), and to use these same links for locking and unlocking.

According to another advantageous characteristic, the spool comprises a piston-shaped extension provided with a retractable cam spring to cooperate with the stop, the piston sliding in one of the control chambers also housing the spring of the return of the drawer in position neutral.

According to another advantageous characteristic, the hydraulic switch is a slide valve provided with a neutral segment and two active segments on either side of the neutral segment to connect one or the other of the two control chambers to the regulated pressure.

According to another advantageous characteristic, the piston has two shoulders formed by the reduced section of the piston and receiving two cups, each having an outer collar and an inner collar, the return spring being supported between the two cups, which support themselves. same according to the movement of the piston against a front support or a rear support of the control chamber by an outer collar and against the shoulders of the piston by an inner collar.

drawings

The present invention will be described in more detail below with the aid of an embodiment of a hydraulic remote control shown in the accompanying drawings, in which: FIG. 1 is a simplified overall diagram of the hydraulic remote control, FIG. 1A is a detail view of the locking member of the remote control according to FIG. 1, FIG. 1B is a sectional view of the distributor part and the associated locking device, FIG. 1C is a detail view. of an embodiment of a hydraulic handle of the remote control installation of FIG. 1, FIG. 2 shows the detailed overall diagram of the hydraulic remote control installation according to the invention shown in a neutral position, FIG. 3A is a diagram of the hydraulic remote control installation according to the invention in its control phase of the actuator in one direction, FIG. 3B is the diagram of the installation corresponding to the return to the neutral position from the activated position of FIG. 3A, FIG. 4A is a diagram of the remote control installation according to the invention actuated to control the actuator in the direction opposite to that represented in FIG. 3A, FIG. 4B is a diagram showing the return to the neutral position from the activated position of FIG. 4A, FIG. 5A shows the diagram of the remote control installation when it is activated to lock the floating position of the 5B is a diagram corresponding to FIG. 5A for the return to the neutral position, FIG. 5C shows the diagram of FIG. 5A for the unlocking of the floating position, FIG. 6 is a diagram of a mode of realization of a known remote control.

Description of embodiments of the invention

According to FIG. 1, the subject of the invention is a hydraulic remote control 1 for controlling a hydraulic actuator 2 such as a double-acting cylinder by a hydraulic circuit powered by a pump 3 and connected to a tarpaulin 4. The hydraulic remote control 1 comprises a lever 11 and a slide valve 12 connecting the pump 3 to the actuator 2. The hydraulic lever 11 consists of the lever and hydraulic members directly actuated by the lever and an example of which will be described using FIG IC .

The slide valve 12 controlled by the lever 11 is interposed between on the one hand the outlet 31 of the pump 3 and its return 41 to the tank 4 and on the other hand, the connections 21, 22 of the two chambers 21a, 22a of the actuator 2. It comprises four control and link segments corresponding to positions: a neutral segment Si blocking the two connections 21, 22 of the chambers and the link 31 with the pump 3 and the return 41 to the cover 4 (position neutral), an actuating segment S2 connecting one 21a of the chambers to the pump 3 and the other 22a to the return 41 to the cover 4 (active position), an actuating segment S3 connecting the chambers 21a, 22a to the pump 3 and the return 41 in the opposite direction of the connections made by the segment S2 (active position), a floating segment S4 connecting the two chambers 21a, 22a to the return 41 to neutralize the actuator 2 whose piston 23 then floats freely (floating position).

The segments S1-S3 correspond to the normal operation of the lever 11 while the segment S4 corresponds to the locking of the floating.

The segment Si is located between the two active segments S2, S3 while the floating segment S4 is located beyond one of the active segments (here the segment S3).

The segments S2 and S3 are equivalent and their activation corresponds for each to a simple direction of control of the actuator 2 and its piston 23.

By convention and to facilitate the description, the direction of movement of the drawer 121 to the left will be called "direct direction D" or "D direction" and its reverse movement, "R direction of return".

The lever 11 controls the movement of the slide 121 in the direction R by a hydraulic connection by supplying the control chamber 122 of the distributor 12; its reverse movement in the direction D is made by a spring, the chamber 122 being connected to the sheet 4.

The slide valve 12 is combined with a locking device 5 to be locked to the operator's control in its floating position of the actuator 2 independent of the lever 11.

The hydraulic lever 11 is connected to the pump 3 by its inlet 111 and to the tank 4 by its outlet 112 and its return 43.

The locking device 5 consists of a locking member 51 (FIG. 1A) associated with the distributor 12, a selector 53 between an output of the hydraulic lever 11 and the distributor 12, a selector 54 between another outlet of the handle 11 and the locking member 51 as well as a hydraulic switch 52 connected to the selectors 53, 54 and the pump 3 via a pressure reducer 55.

The slide 121 of the distributor 12 is connected in translation to the piston 511 of the locking member 51 sliding in a bore 512 and subjected to a return spring 513 acting against the thrust of the slide 121.

The piston is preferably an extension of the slide 121.

The spring 513 acts in the forward direction (D) and also in the return direction (R) to push the piston 511 and the slide 121 or to return them to the neutral position.

The piston 511 comprises a retractable cam 514 projecting from its periphery and the bore 512 has a stop 515 that encounters the cam 514; the relative positions of the cam 514 and the abutment 515 are chosen according to the position of the segments S1-S4 of the slide 121.

The axial position of the abutment 515 is located taking into account the position of the segments S1-S4 of the slide 121 and the translation link with the locking member 51, according to the orientation convention (Figure 1). The floating segment S4 is situated to the right of the operating segment S3, that is to say beyond the segments S1-S3 used for the normal operation of the distributor 12.

The length of the free path of the cam 514 before meeting the stop 515 corresponds to the displacement of the slide 121 in the direction D or R according to the use of the segments S2, Si, S3, to put one of these segments S1-S3 in the active position in which the selected segment is facing the conduits 31, 41; 21, 22.

The hydraulic switch 52 associated with the two selectors 53, 54 makes it possible to lock the distributor 12 in the floating position S4 and also to unlock it from this position.

The switch 52 is in the form of a three-segment 521 drawer servovalve 52, SV2, SV3. It is controlled separately from the handle 11 by an intentional action of the operator. Locking occurs in the neutral position, since a double action of the handle 11 and the simultaneous switch 52 is prohibited by the selectors 53 and 54.

The switch 52 is connected to the input 531 of the selector 53 via a line 531 and to the first input 541 of the selector 54 by a line 541.

The second input 532 of the selector 53 is connected to the output of the joystick 11 and the second input 542 of the selector 54 is connected to another output of the joystick 11.

The output 533 of the selector 53 is connected by the line 533 to the nozzle 564 of the locking member 51 and the output 543 of the selector 54 is connected to the chamber 122 of the distributor 12.

A selector such as the selector 52 or 53 has the function of connecting by its output, the one of the two inputs which is at the highest pressure.

The switch 52 is connected to the two selectors 53, 54 associated with the hydraulic lever 11, the hydraulic fluid source 55 and a return 44 to the tank 4.

The selector 54 is connected to the hydraulic chamber 122 of the slide 121 to actuate it and the other selector 53 is connected to the locking member 51 to supply the chamber 562 of the piston 511.

The segments of the servovalve 52 provide the following hydraulic connections: the segment SVi connects the two selectors 53, 54 to the tank 4 and cuts the connection with the pressure reducer 55 (neutral segment); the segment SV2 connects the pressure reducer 53 to the selector supplying the conduit and the other selector 54 to the tarpaulin 4 (active segment); the segment SV3 connects the selector 53 to the tank 4 and the selector 54 to the pressure reducer 55 in contrast to the SVi segment (active segment).

The hydraulic pressure source is constituted by the pressure reducer 55 supplied to the pressure P1 by the hydraulic pump 3 to supply hydraulic fluid with controlled pressure P2 less than the output pressure P1 of the pump 3: when the segment Si is in position, the pump 3 delivers into the regulator 55 and returns the excess liquid by its return 42 to the tank 4. This excess is equal to the flow rate of the pump 3 when the switch 52 is closed, when the segment S2 is in position active, the pump 3 supplies the chamber 21a, the chamber 22a being connected to the tank by the return 41, when the segment S3 is in the active position, the pump 3 supplies the chamber 22a; the chamber 21a is connected to the tarpaulin by the return 41.

In these three positions of the segments Si, S2, S3, the pump 3 is connected to the switch 52 by the pressure reducer 55.

It should be emphasized that the pressure regulator 55 supplies the switch 52 and the control handle 11 with the controlled pressure P2, but the handle 11 transmits only a reduced regulated pressure P3 at its outputs 532, 542. This pressure P3 is lower at the regulated pressure P2.

As a result, the selector 53 receiving: the regulated pressure P2 at its input 531, the reduced regulated pressure P3 at its input 532, always transmits, under these conditions, the regulated pressure P2 at its output 533. In the unlocked state , the lever 11 controls the movement of the slide in the direction D by feeding the chamber 562, in reduced controlled pressure, P3, sufficient to operate the slide 121 for the segments S2, S1, S3 but insufficient to generate a force allowing the cam 514 to pass on the stop 515. Indeed, for the maneuvering of the handle 11, the hydraulic switch 52 is in position SV2 so that the input 531 of the selector 53 is at atmospheric pressure and the lever 11 feeding the input 531 at the reduced regulated pressure, thus transmits this pressure to the chamber 562 by the pipe 533 to maneuver the slide 121 in the direction D. It should also be noted that the hydraulic lever 11 which comm ande, without locking, the movement of the slide 121, applies to the chamber 122, the reduced regulated pressure P3 which generates a sufficient force to move the slide 121 in one of its positions S2 or S3 but insufficient to pass the cam 514 on the stop 515 in the direction R and thus it can not unlock the drawer 121.

Under these conditions, when the operator wants to lock the actuator 2 in the floating position, he acts on the switch 52 to use the segment SVi which connects the selector 53 to the gearbox 55 to thereby apply the regulated pressure to the chamber 562 of the locking member 51 and push the piston 511 to pass the cam 514 on the stop 515 by retracting against the action of its spring 5113. This movement is possible because the switch connects at the same time the other selector 54 to the tarpaulin 4 so that the slide 121 is no longer subjected to a thrust in the direction R. The force applied to the piston 511 by the controlled pressure P2 must only overcome the retaining force created by the cam 514 and its spring 5113 and also the force of the return spring 513 of the piston 511.

To unlock the slide 121, it has been seen that the operation of the lever 11, in the appropriate direction, allows to apply to the chamber 532 that the reduced regulated pressure P3 which generates insufficient thrust.

The unlocking can only be done by a separate action on the hydraulic switch 52 in the opposite direction to the previous one to use the segment SV3 which connects: the chamber 562 by the pipe 533 and the return of the selector 53 to the return pipe 54 to the cover 4, the line 541, the selector 54, the return 543 and the chamber 122 to the regulated pressure P2 of the regulator 55 generating the force sufficient to retract the cam 514 and pass on the stop 515.

In more detail (FIG. 1A), the cam 514 is a sliding and retractable pin in a radial housing 5111 of the piston 511 under the action of a ball 5112 pushed by a compression spring 5113, to project from its housing radial 5111 or retract it.

For the purpose of balancing the forces, the cam 514 can be completed by another cam in diametrically opposite position or by two other equivalent cams so that the three cams 514 will be distributed equiangularly and meet the peripheral stop 515.

According to the embodiment (Figure 1A), the locking member 51 has a body 56 receiving a sleeve 561 provided with the bore 512 and the peripheral stop 515.

The return spring 513 acts on the piston 511 via two cups 563a, 563b, attached to the piston 511 and bearing as the case, against the rear of the sleeve 561 forming a front support 561a and against the bottom of the chamber 562 forming a rear support 562b.

The cups 563a, b have an outer flange 5631 and an inner flange 5632 bordering their opening by which they are engaged on the cylindrical extension 5115 of reduced section, the piston 511 forming a front shoulder 5114a.

The two cups 563a, b receive between them the return spring 513 preferably leaning on the outer flanges 5631 to reduce the bulk.

A screw 516 is screwed onto the cylindrical extension 5115 to form by its head, the rear shoulder 5114b of the piston, against which the inner collar 5632 of the rear cup 563b engages.

The piston 511 is shown in the neutral position in Figure lA: the spring 513 is expanded to the maximum; the front cup 563a is supported by its outer flange 5631 against the front support 561a and by its inner flange 5632 against the front shoulder 5114a of the piston; the rear cup 563b is in abutment against the rear support 562b by its outer flange and bears against the rear shoulder 5114b of the piston by its inner flange 5632. From this neutral position, when the piston 511 advances (direction D), it compresses the spring 513 by the rear cup 563b and when it moves back, it compresses the spring 513 by the front cup 563a.

The chamber 562 which constitutes the second control chamber of the slide 121 by its piston 511 has a nozzle 564 for receiving the hydraulic fluid controlling the general movement and also the locking movement of the piston 511 by pushing it in the direction D and as the case , strong enough to retract the cam 514 by its support against the abutment 515 and return it in its radial housing 5111 against the thrust of the spring 5113, transmitted by the ball 5112 and pass beyond the stop 515.

Figure 1B shows in section a practical embodiment of the distributor 12 and the locking member 51. The description corresponds to that made above for the schematic representation of the dispenser in Figures 1 and 1A; the references used are the same.

FIG. 1C shows the detail of the hydraulic lever 11 formed of a rocker 110 alternately actuating the drawers 131a, 131b of the two distributors 13a, 13b, each having two identical segments SSi, SS2 and which ensure, one (SSi) the connection between the input 111 and the output 532 or 542 while the connection with the return 112 to the tank 4 is cut off. The other segment SS2 connects the output 532 or 542 to the outlet 112 to the tank 4 and cuts the inlet 111 of liquid under pressure.

It should be noted that for the sake of simplification, the output 532 of the hydraulic lever 11 is also one of the inputs of the selector 53; likewise, the output 542 of the handle 11 is one of the inputs of the selector 54.

The position shown in Figure IC is the neutral position.

Figures 2-5C are used to describe the different operating states of the hydraulic remote control 1. In these figures, the pressure lines or active hydraulic connections, supplied by the pump 3 and, if appropriate, by the pressure reducer 55, are drawn in strong lines and nonactive lines are shown in broken lines. The description will be limited in each case to the position of the various members associated with the neutral position or the operating position of the hydraulic remote control 1.

Figure 2 shows in more detail the overall scheme with the neutral position of the remote control 1. The handle 11 is in the neutral position. Its distributors 13a, 13b cut off the arrival of the pressurized liquid from the inlet 11 and put in communication with the outlet 112, the various internal pipes of the remote control unit. The distributor 12 is in the neutral position. The segment Si of its spool 121 faces the lines 21, 22 which are blocked, as well as the lines 31 and 41. The switch 52, in neutral position, intersects with its segment SVi the liquid supply of the pump 3 by the regulator 55. The selectors 53, 54 are not stressed and the piston 511 is in the neutral position. Its cam 514 is not applied against the stop 515.

FIG. 3A shows the action of the lever 11 of the remote control to activate the distributor 12 and put the segment Sa in the active position so as to control the actuator 2.

For this, the handle 11 is toggled. It drives the drawer 131b of the distributor 13b and raises the 131a of the distributor 13a. The segment SSi connects the input 111 coming from the pressure reducer 55 fed by the pump 3, to the selector 54 whose other input is connected through the segment SVi of the hydraulic switch 52 to the tank 4 so that it is without pressure. The selector 54 thus transmits the liquid under pressure regularly to the chamber 122 to act on the slide 121 and push it into the active position for the segment S2 which thus connects the pipe 21 to the chamber 21a to feed it with liquid under pressure directly. from the pump 3.

If then the handle 11 is released, it is returned to the neutral position by its springs (Figure 3B). The drawers 131a, 131b cut the arrival of liquid by their segment SS2. At the same time, the SS2 segments connect the selector 54 to the return 43 to the cover 4; this allows the slide 121 to return under the pressure of the spring 515 acting on the piston 511, to thereby come to the neutral position (segment Si) cutting the lines 21, 22. The liquid is blocked in the chambers 21a, 22a so that the piston 23 is itself locked in its position at the end of actuation of the lever 11.

FIG. 4A shows the action produced by the tilting of the lever 11 in the opposite direction to that of FIG. 3A.

This switching puts the segment SSi of the distributor 13a in the active position so as to make the hydraulic fluid inlet 111 communicate with the input 532 of the selector 53 whose other input 531 is at ambient pressure since connected to the return 44 to the cover by the neutral position of the hydraulic switch 52 (segment SV2 of its drawer 521).

The reduced regulated hydraulic fluid P3 is thus transmitted via the outlet 533 and the pipe 533 to the control chamber 562 of the locking member 51 so that the pressure is applied to the piston 511 and pushes back this against the force exerted by the spring 513 on the rear cup 5631. The piston 511 advances in the direction D and drives the slide 121 which puts the segment S3 in the active position, thus connecting the chamber 22a of the actuator 2 to the pipe 31 supplying the hydraulic fluid under pressure and the chamber 21b to the return 41 to the tank 4. The slide 121 is moved in this movement in the direction D and stops in front of the stop 515 because this thrust is not sufficient to that the piston 511 can drive the cam 514 and pass beyond the stop 515.

Figure 4B shows the end of the operating phase of the handle 11 and its return to the neutral position as it happened at the end of the operation of the handle 11 according to Figure 3A. The return to neutral position is as in Figure 3B and results in the locking of the piston 23 of the actuator 2 in its position at the end of the movement according to Figure 4A.

When the lever 11 is released, the distributors 131a, 131b resume the neutral position cutting the inlet of liquid under pressure so that the return spring 513 brings the slide 121 to its neutral position, the segment Si coming into the active position and cutting the connection between the pipes 21, 22 and the respective pipes 31.41. The piston 23 of the actuator 2 is thus locked in its position by the two volumes of liquid blocked in the chambers 21a, 22a.

Figure 5A shows the passage of the stop 515 by the cam 514 to lock the actuator 2 in the floating position connecting the chambers 21a, 22a to the sheet 4 through the segment S4 of the slide 121 in the active position.

For this, starting from the neutral position Si of the distributor 12 according to FIGS. 3B, 4B in which the actuator 2 is blocked, the operator pushes on the switch 52 to put his segment SV2 in the active position from the neutral position SVi in which was its drawer 521 for the various control movements described above.

In the active position, the segment SV2 connects the line f531 of the input 531 of the selector 53 to the controlled pressure liquid line P2 coming from the gearbox 55 while the input 541 of the selector 54 is connected by the line 541 to the line back 44 to the tarpaulin 4.

The regulated pressure P2 of the liquid transmitted via the line 533 to the chamber 562 of the piston 511 generates a thrust sufficient to retract the cam 514 and pass beyond the stop 515 and the slide 121 places its segment S4 in the active position connecting the two conduits 21, 22 and the chambers 21a, 22a at the return 41 to the tank 4. The segment S4 interrupts the arrival of liquid under pressure of the pipe 31 and as the pipes 21, 22 are connected to the return 41 to the tank 4, the piston 23 is in the floating position in the actuator 2.

Since the lever 11 is not activated, the distributors 13a, 13b are locked with their segment SS2 in the active position so as to connect all the lines of the lever 11 to the return line 44 to the tank 4 via the outlet 112 and block the inlet 111 of liquid under pressure.

Figure 5B shows the return to neutral position. When the action on the switch 52 stops; the slide 521 can be returned to the neutral position: its segment SV2 then connects the inputs (outputs) of the selectors 53, 54 to the return line 44 to the tank 4 and blocks the arrival of liquid under pressure. If the drawer 521 keeps its active position SV2, this does not change the lock of the distributor 12.

The distributors 13a, 13b are normally themselves in the neutral position (segment SS2 active), the liquid supply under pressure of the regulator 55 is blocked and the drawer 121 of the distributor can not be moved. Even in the absence of pressure in the chamber 562, the accidental or unintentional tilting of the lever 11 would only supply the chamber 122 with the reduced regulated pressure P3, which would not generate a sufficient thrust in the direction R to push the piston 51 and its cam 514 beyond the stop 515. The actuator 2 remains in the floating position.

Figure 5C shows the unlocking. For this, the operator actuates the switch 52 to move the drawer 521 to the left (D) and put the segment SV3 in the active position. In this position, it connects the selector 54 to the liquid inlet 111 under controlled pressure P2 coming from the reducer 55 while the chamber 562 is connected by the selector 53 to the return 44 to the cover 4. The liquid of the chamber 562 can escape as a result of the thrust of the spring 513. As by this direct connection of the selector 54 to the regulator 55, the selector 54 supplies the chamber 122 of the distributor 12, the regulated pressure P2 (and not the reduced regulated pressure P3 used for the usual control of the slide 121) generates a sufficient thrust to push the slide 121 in the direction R and thereby the piston 511 so as to overcome the stop 515 and pass the cam 514 on the other side thereof .

FIG. 6 shows the diagram of a known remote control 100 whose lever 11 acts on two slide distributors 13a, 13b like those described above but whose outputs are respectively connected to the chambers 122, 123 on both sides of the drawer 121 for control it from the neutral position If represented by the tilting of the handle 11 on one side or the other to supply one of the two chambers of the distributor 12 and push the drawer 121.

This drawer 121 has a segment S4 allowing the float position of the actuator 2 as long as the handle is pushed in this direction.

In summary, the remote control according to the invention characterized in that it comprises: A. a distributor (12) with a slide (121) connecting the pump (3) and the cover (4) to the actuator (2), the drawer (121) having, on either side, a neutral segment (Si), two active segments (S2, S3) for controlling the actuator (2) and beyond these segments (S2, S3 ) of the actuator (2) and beyond these segments (S2, S3), a floating segment (S4), two hydraulic control chambers (122, 562) for controlling the drawer in both directions ( D, R), a stop (515) for the movement of the slide (121), separating the range of movement of the slide (121) comprising the control segments (S2, S3) and its floating segment (S4), B. a hydraulic handle (11) for controlling the spool (121) in both directions by the two control chambers (122, 562), the hydraulic lever (11) being fed with a regulated hydraulic pressure (P2) less than the pressure outlet (PI) of the pump (3) and outputting a reduced regulated pressure (P3) supplying one or the other control chamber (122, 562), this pressure (P3) being lower than the regulated pressure (P2), the reduced regulated pressure (P3) being sufficient to generate a thrust to move the spool (121) and activate one or the other of these active segments (S2, S3) from the neutral segment (Si) , but insufficient to generate a thrust allowing the spool (121) to pass the stop (515), C. a hydraulic locking device (5) comprising a hydraulic switch (52) controlled independently of the hydraulic lever (11) to feed alternately one or other of the two chambers (122, 562) with hydraulic fluid at the controlled pressure (P2), to generate a thrust on the slide (121), sufficient to pass the stop (515).

NOMENCLATURE 1 Hydraulic remote control 11 Joystick 110 Pendulum 111 Entry 112 Return 113 Exit 114 Exit 12 Drawer 121 Drawer 122 Room 123 Room 13a, b Drawer 131a, b Drawer 2 Hydraulic Actuator 21, 22 Link 21a, 22a Room 23 Piston 3 Pump 31 Output 4 Cover 41-44 Back 5 Locking device 51 Locking element 511 Piston 5111 Radial housing 5112 Ball 5113 Spring 5114a Front shoulder 5114b Rear shoulder 5115 Cylinder extension 512 Bore 513 Return spring 514 Retractable cam 515 Stop 516 Screw 52 Switch / servovalve 521 Drawer 53 Selector 531 First input 532 Second input 533 Output 54 Selector 541 First input 542 Second input 543 Output 55 Pressure reducing valve 56 Locking element body 561 Sleeve 561a Front support 562 Control chamber 562b Rear support 563a, b Cup 5631 Outside Collar 5632 Inner Collar 564 Nozzle 1 00 Known hydraulic remote control 123 D chamber Direct direction R Return direction 51, S2, S3, S4 Drawer segments

If Neutral segment 52, S3 Active segment S4 Floating segment SVi Neutral segment SV2 Active segment SV3 Active segment PI Pump output pressure P2 Regulated pressure P3 Reduced regulated pressure

Claims (5)

1 °) Hydraulic remote control for a hydraulic actuator with double effect, characterized in that it comprises: A. a distributor (12) with drawer (121) connecting the pump (3) and the tarpaulin (4) to Tactionneur (2) ), the slide (121) having, on either side, a neutral segment (Si), two active segments (Sa, Ss) of the actuator control (2) and beyond these segments (Sa, S3) of the actuator (2) and beyond these segments (Sa, S3), a floating segment (S4), two hydraulic control chambers (122, 562) for controlling the drawer in both directions (D , R), a stop (515) for the movement of the slide (121), separating the range of movement of the slide (121) comprising the control segments (Sa, S3) and its floating segment (S4), B. a hydraulic handle (11) for controlling the slide (121) in both directions by the two control chambers (122, 562), the hydraulic handle (11) being fed with a regulated hydraulic pressure ee (P2) lower than the output pressure (PI) of the pump (3) and outputting a reduced regulated pressure (P3) supplying one or the other control chamber (122, 562), this pressure (P3) being less than the regulated pressure (P2), the reduced regulated pressure (P3) being sufficient to generate a thrust to move the slide (121) and activate either of these active segments (S2, S3) from the segment neutral (Si), but insufficient to generate a thrust allowing the spool (121) to pass the stop (515), C. a hydraulic locking device (5) comprising a hydraulic switch (52) controlled independently of the hydraulic lever (11) ) for alternately supplying one or the other of the two chambers (122, 562) with hydraulic fluid at the controlled pressure (P2), to generate a thrust on the slide (121), sufficient to pass the stop (515). 2) Hydraulic remote control according to claim 1, characterized in that the hydraulic locking device (5) comprises two selectors (53, 54) and each selector (53, 54) is connected at the output to the hydraulic connection (533, 543 ) of one of the control (122, 562) and input (531, 541/532, 542) chambers at one of the outputs of the hydraulic switch (52) and at one of the outputs of the hydraulic handle (11), the other selector (54, 53) being connected at the output to the other control chamber and at the input to the other output of the hydraulic switch (52) and the hydraulic lever (11) for supplying regulated pressure (P2) l one or the other of the control chambers (122, 562). 3 °) hydraulic remote control according to claim 1, characterized in that the slide (121) comprises a piston-shaped extension (511) provided with a retractable cam (514) spring (5112, 5113) to cooperate with the stop (515), the piston (511) sliding in one of the control chambers (562) also housing the spring (513) of the return of the slide (121) in the neutral position (Si). 4 °) hydraulic remote control according to claims 1 and 2, characterized in that the hydraulic switch (52) is a slide valve (521) provided with a neutral segment (SVa) and two active segments (SVi, SV3) of on either side of the neutral segment (SV2) for connecting one or the other of the two control chambers (122, 562) to the regulated pressure (P2). 5 °) hydraulic remote control according to claim 3, characterized in that the piston (511) has two shoulders (5114a, 5114b) formed by the reduced section of the piston and receiving two cups (563a, 563b), each having an outer collar ( 5631) and an inner flange (5632), the return spring (513) being supported between the two cups (563a, 563b), which bear themselves according to the movement of the piston (511) against a front support (561a). ) or a rear support (562b) of the control chamber (562) by an outer collar (5631) and against the shoulders of the piston (511) by an inner collar (5632).