FR2783539A1 - CONTROL DEVICE FOR A PUBLIC WORKS MACHINE - Google Patents

Abstract

The control system for a self-propelled civil engineering vehicle with working implements consists of one circuit with control levers (10) for the movement of the chassis, and another with a tilting console (3) and handle (2) for the hydraulic circuit controlling the implements. It has a locking mechanism for the control levers (10) which is actuated automatically by a spring (45) when the console is pivoted into its retracted position and comprises a cable (40) linked to the console, and a mechanical relay (20) with a locking member on one arm which engages with a notch (16) in the lever end.

Description

i CONTROL DEVICE FOR A PUBLIC WORKING MACHINE Technical area

  The invention relates to the field of public works machinery. More specifically, it relates to an improvement of the control device prohibiting the involuntary actuation of the translation controls of the vehicle when the driver has left his driving position. Previous techniques As is known, a public works machine is generally equipped with a self-propelled chassis and working equipment. The cockpit includes a certain number of controls allowing to control the movement of the machine on the ground as well as the deployment and the orientation of the work equipment. The control device therefore has a control circuit in translation of the self-propelled chassis, actuated by the movement of articulated levers which can be in the form of manual manipulators, and / or pedals located at the

  cockpit floor level. This control circuit actuates, by a set of linkages or cables, the control of the hydraulic propulsion motor (s) and the rotation of the different axles or tracks, possibly in a differentiated way from one side to the other of the machine. .

  In addition, the driver has at his disposal a certain number of manipulators acting on the hydraulic circuit of the various jacks mounted on

  work equipment. These manipulators also make it possible, in the case where the machine has a pivoting turret, to ensure its rotation relative to the self-propelled chassis.

  It is understood that accidental or involuntary operations of the work equipment and / or the turret can cause significant damage when they are not controlled. This is why no unexpected movement of the turret or of the work equipment should take place when the driver has left the driving position. Thus, most of the current machines are equipped with a device for blocking the controls of the work equipment when the driver leaves the driving position.35 In practice, the various manipulators controlling the hydraulic circuit of the work equipment and of the turret are mounted on a console located

  laterally with respect to the conductor. When the latter wishes to leave the driver's seat, he must pivot or retract the console carrying the 5 manipulators to descend from the machine.

  In known manner, the retraction movement or the pivoting of the console causes, by means of an appropriate member, the breaking of the control circuit

  hydraulics of work equipment and / or turret. In this way, as long as the driver is outside the driving position, it is impossible for the work equipment to deploy unexpectedly.

  A problem which the invention proposes to solve is that of ensuring total safety by avoiding any unexpected control of the hydraulic motors.

  of the chassis when the driver has left his driving position.

  To solve this problem, it has already been proposed to equip the translational control levers with locking systems by a mechanical system of a pivoting fork which the driver must fold down on the lever before leaving his machine. Unfortunately, such a device is independent of the cut-off device of the hydraulic circuit of the work equipment, and unlike this

  last, the driver must perform a voluntary maneuver to lock the controls in translation.

  It is therefore easy to see that such a solution is extremely imperfect, because it does not make it possible to guard against an oversight by the driver, of which it therefore does not provide total security. SUMMARY OF THE INVENTION The invention therefore relates to a device for controlling a public works machine comprising a self-propelled chassis and working equipment, having: * a circuit for controlling the self-propelled chassis in translation, actuated by the movement of levers articulated; * a hydraulic control circuit for the work equipment, actuated by at least one manipulator mounted on a console capable of pivoting between a working position and a retracted position, the hydraulic circuit being equipped with a member capable of cutting it when the swivel console

goes into the retracted position.

  This device is characterized in that it further comprises means for blocking the movement of the articulated levers of the control circuit in translation, when the pivoting console passes into the retracted position. In other words, the invention consists in ensuring the locking of the control levers or pedals in translation when the driver raises the console carrying the control manipulators of the work equipment. In this way, when the driver prepares to leave his machine, he automatically locks both the control circuits of the work equipment and the movement of the machine, in a single maneuver which he is obliged to realize if he wants to get off the cockpit. This blocking of the movement of the translation control levers is independent of the very nature of the translation control circuit which can be carried out by linkage, by cable, or even

  even by an electric or hydraulic circuit.

  In practice, the means for blocking the translation control levers consist of: - a mechanism for controlling the blocking means, actuated by the pivoting of the console, and comprising, near the translation control levers, an element of which the position depends on the position of the console; - a mechanical relay mounted to pivot about an axis between a rest position and a locking position, said relay consisting of two arms, the free end of the first arm being integral with the element of the mechanism

  control, so that the mechanical relay is pivoted in the locked position when the console passes into the retracted position, the free end of the other arm carrying a locking member capable of coming to engage in a housing provided for this purpose on the control lever in translation, when the relay is pivoted in the locked position.

  In other words, the pivoting of the console causes the introduction of the locking member in a part of the control lever in translation so

  that it is then impossible to operate it after this locking.

  It can happen that when the driver raises the console to exit the driving position, the translational control manipulator is in an engaged position. To allow the control lever to be locked in translation when it is slightly maneuvered, the control mechanism 5 of the locking means comprises a tension spring ensuring a return force of the mechanical relay in the locked position when the console is in position retracted. In this way, as soon as the console is raised, the tension spring acts on the

  relay to force it to engage in the control lever in translation as soon as the locking member comes opposite the housing.

  In addition, the part of the end of the lever capable of coming into contact with the mechanical relay is designed so that the blocking member penetrates inside the housing regardless of the position of the control lever. That

  this prevents the control lever from being locked in the engaged position due to the action of the mechanical relay.

  In practice, the mechanism for controlling the locking means can be made up: - either by a cable connected to the console, - or by an electrical circuit supplying an electromagnet, the position of the moving assembly of the electromagnet being a function of the console position; - Either by a hydraulic cylinder associated with a return spring, the chamber of said hydraulic cylinder being supplied by the hydraulic circuit for controlling the work equipment, and the position of the piston of the cylinder

  being a function of the position of the console.

  In a particular embodiment, the housing provided on the lever in translation has a flared opening, so as to guide the engagement

of the blocking member.

  In this way, the finger is allowed to enter the blocking housing,

  whatever the position of the manipulator in the vicinity of the rest position.

  Indeed, taking into account the manufacturing tolerances as well as the different offsets observed in the distributors, the control manipulator in

  translation can have a neutral position which varies slightly. In this way, the flared shape can compensate for these small shifts.

  In an alternative embodiment, the mechanical relay further comprises a torsion spring, ensuring an effort to return the mechanical relay to the position of

  rest. In this way, in the case where the control mechanism of the blocking means should fail, for example if it is a cable if it is cut, the relay is automatically placed in the rest position, so as not to permanently block the operation of the control lever in translation.

  In practice, the housing for receiving the blocking member is formed by at least one fork open in the direction of said member.

Description of the figures

  The manner of carrying out the invention, as well as the advantages which result therefrom, will emerge clearly from the description of the embodiments which follow, in support

  appended figures in which: 20 * Figure 1 is a schematic side view of the assembly formed by the console supporting the control manipulator of the work equipment, as well as the control lever in translation, connected by the mechanism blocking means control unit, all shown in

working position.

  * Figure 2 shows the elements of Figure 1 in the locked position; * Figure 3 is a side view of the mechanical relay; * Figure 4 is a detail side view of part of the mechanical relay of Figure 3, showing the two arms; * Figure 5 is a top view of the mechanical relay of Figure 3 * Figure 6 is a side view identical to Figure 1, in which the control mechanism of the locking means are made by a cylinder

  hydraulic associated with a return spring.

  Manner of Realizing the Invention As already said, the invention relates to a device for controlling a driver's position of public works machines making it possible to block the 6 commands in translation simultaneously with the blocking of the circuit commands

  hydraulic work equipment.

  Thus, as seen in FIG. 1, the control of the hydraulic circuit is ensured by a manipulator (2), mounted on a console (3) forming an armrest, and generally placed to the right or left of the driver, between the latter and the driving area access area. The console (3) has an ergonomic shape, the armrest allowing the driver to have the forearm rested when he actuates the manipulator (2). This manipulator (2) is connected in a known manner to the hydraulic circuit 10 for controlling the work equipment and the turret, not shown, and known as such, so that it is not necessary to describe it.

here in more detail.

  In known manner, the console (3) supporting the manipulator (2) is pivotally mounted relative to an axis (4). In known manner, the pivoting of the console (3) causes, by a known device not shown, the power supply cut off from the hydraulic circuit for controlling the work equipment and the turret. Of the

  so, when the driver raises the armrest (3), the manipulator (2) becomes inoperative and cannot cause the displacement of the turret or of the work equipment by a shock or an unexpected operation.

  Furthermore, the public works machine can be brought to move on the ground by the action of the control lever in translation, illustrated in FIG. 1 by a manual manipulator (10), but which can, without leaving the frame of the invention, be25 replaced or supplemented by a pedal located at the floor of the driving position; This lever (10) is mounted on a support housing (11). It is articulated with respect to an axis (12) and extends below this axis by a lower portion (13). On this lower portion (13), is connected a linkage (14) or a cable connected to the motor, or more generally to the mechanism causing the advance or the

translation of the machine.

  According to the invention, the lower end (13) of the lever (10) of

  translation control has a flared fork (16) open at the bottom.

  In addition, the housing (11) for supporting the lever (10) for translational control has, in accordance with the invention, a mechanical relay (20) mounted articulated by an axis (21) parallel to the axis (12) of lever pivoting. This mechanical relay (20) comprises two arms (22,23) as can be seen in detail in FIG. 3. These two arms 5 (22,23) are found substantially in configuration at right angles. The arm (22) has in its upper part (25) a notch (26) allowing the attachment and the

  attachment to the control means of the blocking device described below. The other arm (23) has a semi-cylindrical notch (28) intended to receive the actual locking member constituted by a rod (30), intended to penetrate into the fork (16).

  According to the invention, the mechanical relay (20) is coupled to the console (3) by the control means illustrated in Figures 1 and 2. In the form shown, this control mechanism consists of a cable (40) connected par15 one of its ends (41) to the console, while its opposite end (42) is connected, by means of a tension spring (45) to the notch (26) of the arm (22)

  mechanical relay (20). The cable routing (40) follows the layout of the driving position.

  More specifically, the end of the cable (41) connected to the console is integral with a cam (50) mounted near the axis of rotation (4) of the console (3) relative to the rest of the driving position. . This cam (50) has a cylindrical outer surface and advantageously has a groove in which the cable is housed when the cam pivots.

  Figures 1 and 2 illustrate the device according to the invention in its two extreme positions, respectively working and blocking.

  Thus, as seen in Figure 1, when the console (3) is in the working position, that is to say horizontal, the cable (40) is released, that is to say pushed back into its sheath. The mechanical relay (20) which is pivotally mounted relative to the axis (21),

  is pushed back into the position illustrated in Figure 1 by a torsion spring located at the axis (21) and not shown.

  It follows that the locking member (30) is offset in the lower part and out of reach of the housing formed by the fork (16) of the lower end of the lever. Conversely, as illustrated in FIG. 2, when the console (3) is retracted, or raised, the cam (50) is pivoted and exerts traction on the cable (40) of the control mechanism. This cable (40) is therefore pulled inside its sheath, and its end (42) therefore pulls on the arm (22) of the mechanical relay (20). 5 It follows that this relay (20) pivots relative to the axis (21) and that consequently, the locking pin (30) penetrates inside the fork (16) forming

the lower end of the lever.

  In this way, the lever (10) is blocked in the neutral position and any operation which would cause the movement of the machine is impossible.

  According to the invention, the shape of the fork (16) is slightly flared to allow engagement of the locking pin (30) of the relay (20) even if the lever (10) for translational control is slightly offset from to the theoretical neutral position. Indeed, we know that by the manufacturing tolerances, and especially the games inherent in the use of hydraulic distributors, the neutral position can cover a certain angular range. The use of this flared shape therefore makes it possible to overcome these different tolerances and offsets. 20 According to a characteristic of the invention, the end of the cable (42) located near the control lever in translation, is equipped a tension spring (45). Indeed, in the case where the lever (10) for translational control is moved from its neutral position, the pivoting of the mechanical relay (20) is blocked by the ends of the fork (16). The retraction of the console (3) nevertheless remains possible, thanks to the elongation capacity of the characteristic spring (45). So,

  when subsequently, the control lever in translation (10) returns to the neutral position, the force exerted by the characteristic spring (45) allows the mechanical relay (20) to pivot and the entry of the locking finger (30) in the fork (16), and hence 30, the locking in the neutral position of the control lever (10).

  In addition, the lower end of the lever (10) is designed so that the locking finger (30) cannot escape from the fork (16) when the spring (45) exerts

  its action. In this way, it is impossible for the lever (10) to be kept locked in the engaged position under the effect of the mechanical relay (20).

  Obviously, the invention is not limited to the embodiment illustrated in FIG. 1 in which the retraction of the console is transmitted mechanically to the mechanical relay, but quite obviously, it covers the different variants in which the control mechanism blocking means 5 is done electrically, for example with an electromagnet associated with the mechanical relay and the supply of which depends on the position of the console. In this case, in the event of a failure of the electromagnet's control system, a return spring ensures the return of the mechanical relay to the unlocked position to avoid unexpected blocking of the control lever (10) .10 Another variant is illustrated in Figure 6 in which the mechanical relay (20) is actuated by a hydraulic cylinder (60) equipped with a return spring (61). More specifically, the hydraulic cylinder is supplied by a hydraulic circuit (62) which is cut, like the main circuit, during the pivoting of the console (3) .15 Thus, when the supply to the cylinder (60 ) ceases, the pressure in the chamber (64) of the latter drops and under the effect of the action of the spring (61) in compression, the piston (65) exerts the force on the arm (23) of the mechanical relay (20) to cause the latter to pivot and the locking finger (30) to engage in the fork (16) of the lever (10) .20 Obviously, this hydraulic variant of the mechanism for controlling the locking means can also be equipped with a spring equivalent to

  spring referenced (45) in Figures 1 and 2.

  It follows from the above that the control device according to the invention has the following advantages: - simultaneous blocking of the control circuit of the work equipment and of the control circuit in translation; - the simultaneous control of the cut-off of the hydraulic circuit for controlling the work equipment and of the machine's translation drive; - automatic locking without any particular operation, as soon as the driver raises the console supporting the manipulator; - insensitivity to the different manufacturing tolerances of mechanical parts and to the different offsets inherent in the use of hydraulic distributors; a return to the locking position of the translational control manipulator even if the latter is out of the neutral position when the console carrying a hydraulic circuit control manipulator is raised; - the impossibility of locking the control lever in translation in an engaged position when the console is raised; - the impossibility of untimely blocking, and therefore immobilization of the machine in the event of a deficiency in the control mechanism of the blocking means,

  for example a cable break, or a lack of energy source.

Claims (8)

  1 / Control device for a public works machine comprising a self-propelled chassis and working equipment, having: * a circuit for translational control of the self-propelled chassis, actuated by the movement of articulated levers (10); * a hydraulic control circuit for the work equipment, actuated by at least one manipulator (2) mounted on a console (3) able to pivot between a working position and a retracted position, the hydraulic circuit being equipped with a member capable of cutting it when the pivoting console (3) passes into the retracted position, characterized in that it further comprises means for blocking the movement of the levers (10) articulated of the control circuit in translation, when the pivoting console ( 3) goes into the retracted position. 15 2 / control device according to claim 1, characterized in that the locking means of the articulated levers are constituted by: - a mechanism (10) for controlling the locking means, actuated by pivoting of the console (3), and comprising, near the control levers (10) in translation, an element (42) whose position is a function of the position of the console; - a mechanical relay (20) pivotally mounted about an axis (21) between a rest position and a locking position, said relay (20) consisting of two arms (22,23), the free end (25 ) of the first arm (22) being integral with the element (42) of the control mechanism, so that the mechanical relay (20) is pivoted in the locked position when the console (3) moves into position   retracted, the free end of the other arm (23) carrying a blocking member (30) able to engage in a housing (16) provided for this purpose on the lever (10) for translational control, when the relay (20) is pivoted to the locking position.   3 / control device according to claim 2, characterized in that the control mechanism of the locking means comprises a spring (45) of   traction ensuring a return effort of the mechanical relay (20) in the locking position when the console (3) is in the retracted position.   4 / control device according to claim 2, characterized in that the control mechanism of the locking means is constituted by a cable (40) connected to the console.   5 / control device according to claim 2, characterized in that the housing (16) formed on the lever in translation has a flared opening,   so as to guide the engagement of the locking member (30).   6 / control device according to claim 2, characterized in that   the mechanical relay (20) further comprises a torsion spring, ensuring an effort to return the relay to the rest position.   7 / control device according to claim 2, characterized in that the housing is formed by at least one open fork (16) in the direction of the locking member.   8 / control device according to claim 2, characterized in that the control means of the locking means are constituted by an electric circuit supplying an electromagnet, the position of the movable assembly of   the electromagnet being a function of the position of the console.   9 / control device according to claim 2, characterized in that the control means of the locking means are constituted by a hydraulic cylinder (60) associated with a return spring (61), the chamber (64) of said hydraulic cylinder 25 being powered by the hydraulic circuit (62) for controlling the work equipment, and the position of the piston (65) of the jack being a function of the position of the console (3).