WO2009050746A2

WO2009050746A2 - Backhoe loader

Info

Publication number: WO2009050746A2
Application number: PCT/IT2007/000723
Authority: WO
Inventors: Matteo Magrin
Original assignee: Komatsu Utility Europe S.P.A.
Priority date: 2007-10-17
Filing date: 2007-10-17
Publication date: 2009-04-23
Also published as: WO2009050746A3

Abstract

A backhoe loader with a control position (1) comprises at least one control console (12) positioned close to the seat (9), and operating means (11) for the rear working arm (6) which can be operated by an operator sitting on the seat (9) located in its rear position, at least part of these operating means being mounted on the control console (12). The control console (12) can also move between a lateral position in which it is at the side of the seat (9) located in its front position, and an operating position in which it is in front of the seat (9) located in its rear position, so that the second operating means (11) can be operated by an operator sitting on the seat (9) located in its rear position.

Description

Backhoe loader

Technical Field

The present invention relates to a backhoe loader, and in particular its control position.

Background Art

As is known, backhoe loaders have a front loading shovel and a rear articulated arm supporting a bucket (and with which other working devices may also be associated). An example of a backhoe loader is illustrated in Figure 23.

Thanks to their structure, they are very versatile machines able to circulate on the road and on sites, and allowing both the movement of material and digging.

A cab is mounted on the central zone of the chassis. Inside the cab is the operator control position.

The control position usually comprises a seat which can be rotated through at least 180° between a front position (in which it is facing the front of the backhoe loader) and a rear position (in which it is facing the back of the backhoe loader), and a plurality of control and check devices which allow backhoe loader driving and use of the front arm, supporting the loading shovel, and of the rear arm. hi particular, when the seat is in the front position, the steering wheel and the dashboard for driving the backhoe loader both on the road or on sites are in front of it. Moreover, again with the seat in the front position, the operator has access to first operating means for moving the loading shovel.

In contrast, when the seat is in the rear position, the operator usually has available second operating means for moving the rear arm. At present, various types of control position are known and used, differing both as regards the first and the second operating means.

As regards the first operating means, in the two most widespread versions the control for moving the loading shovel consists of a hydraulic controller mounted, respectively, on the dashboard in front of one of the armrests of the seat or directly at the end of the armrest.

The other control and check devices which are part of the first operating means are usually positioned either on the front dashboard, or on another dashboard at the side of the seat (near the controller, if necessary). However, the prior art embodiments of the loading shovel controller are not without disadvantages.

The controller in a fixed position in front of the seat is first relatively inconvenient to use, since it does not fulfil ergonomic requirements. The position of the controller remains the same irrespective of the position of the seat, which may be raised, lowered, moved forward or backward, according to operator requirements.

Secondly, in many machines currently sold, given the limited space available, the operator's arm may interfere with other control levers located close to the controller. In contrast, when the controller is fixed to the seat, the main disadvantages are linked to dimensions. The presence of the controller may interfere both with the operator's activities while driving the vehicle, and with other parts of the control position (such as the steering wheel) during seat rotation.

Moreover, with said type of controller its distance from the seat cannot be adjusted.

However, the most significant disadvantages relate to the second operating means, and this invention was developed primarily with relation to these.

In particular, the most dated embodiment has a plurality of control levers pivoting at the floor of the rear zone of the control position. Said levers, as well as being quite inconvenient to use because they require extensive movements by the operator, constitute an obstacle when the seat has to be rotated (with the operator sitting down) from and to the rear position.

In contrast, in a second embodiment the backhoe control devices consist of two hydraulic/electric controllers hooked to the seat armrests. In this case, normally, at least one of the two controllers can switch according to the position of the seat to control the front loading shovel or the rear arm. With this second operating means configuration, the main disadvantage is difficulty rotating the seat without the controllers striking other parts of the cab. Consequently, when it is time to rotate the seat, the operator must also translate it forward or backward or raise or lower it, or lift the armrests.

Secondly, as already indicated, the fact that the position of the controllers relative to the seat cannot be adjusted fails to satisfy ergonomic requirements.

Another embodiment involving the use of two controllers is described for example in patents US 6,564,896 and EP 1 627 962. In this case, each controller is mounted at the top of a tower assembly whose base pivots at the floor of the control position. Therefore, each tower assembly can rotate between a position in which the controller is close to the seat and a position in which the controller is distanced from the seat (towards the back of the backhoe loader). Said embodiment substantially solves the problem of controller interference during seat rotation. But on one hand it is not optimum from an ergonomic viewpoint, because it does not allow height adjustment of the position of the controllers relative to the armrest, and on the other hand it means that the operator has to pull the tower assemblies towards him on each occasion to put them in the correct position.

All prior art embodiments of the second operating means also have the disadvantage that, to avoid problems with interference, all of the other control and check devices are positioned on a dashboard at the side of the seat, that is to say, in a quite inconvenient position for relative use. Disclosure of the Invention

In this situation, the technical purpose which forms the basis of the present invention is to provide a backhoe loader which overcomes the above-mentioned disadvantages. In particular, the technical purpose of the present invention is to provide a backhoe loader in which all of the steps relative to use of the second operating means are extremely easy and ergonomic.

The present invention also has for a technical purpose to provide a backhoe loader in which use of the first operating means is also easy and ergonomic. The technical purpose specified and the aims indicated are substantially achieved by a backhoe loader as described in the claims herein.

Brief Description of the Drawings

Further features and advantages of the present invention are more apparent in the detailed description below, with reference to a preferred, non-limiting embodiment of a backhoe loader, illustrated in the accompanying drawings, in which:

Figure 1 is a schematic perspective view with some parts cut away to better illustrate others, of a control position of a backhoe loader made in accordance with the present invention;

Figures 2 to 6 illustrate, from the same viewpoint as Figure 1 , several steps one after another which lead to a variation in the configuration of the control position of Figure 1;

Figure 7 illustrates from a different angle the control position in the configuration of Figure 3;

Figures 8 to 12 are perspective views from the viewpoint of Figure 7, of the detail of the system for moving the control position in steps one after another during the passage from the configuration of Figure 1 to that of Figure 6, all with the seat adjusted according to a first limit method; Figure 13 is a perspective view, from the same viewpoint as Figures 8 to 12, of the detail of the system for moving the control position, in an intermediate step during the passage from the configuration of Figure 1 to that of Figure 6, with the seat adjusted in this case according to a second limit method opposite to the first;

Figures 14 to 17 are perspective views from the viewpoint of Figure 1, of the detail of Figures 8 to 13, in steps one after another during the passage from the configuration of Figure 1 to that of Figure 6, all with the seat adjusted according to an intermediate method between that of the previous figures;

Figure 18 is a perspective view of a detail of the control position of Figure i; Figure 19 illustrates the detail of Figure 18 after a movement of the seat according to the arrows F of Figure 18;

Figure 20 is a perspective view of a detail of the control position of Figure

6;

Figure 21 illustrates the detail of Figure 20 after a movement of the seat according to the arrows F of Figure 20;

Figure 22 shows a detail of the control console of Figure 4; and Figure 23 is a schematic side view, partly transparent, of a backhoe loader on which the control position illustrated in the previous figures may be applied.

Detailed Description of the Preferred Embodiments of the Invention

With reference to the accompanying drawings, the numeral 1 denotes as a whole a control position of a backhoe loader 2 made in accordance with the present invention.

Similarly to the prior art types, the backhoe loader 2 has a chassis 3 mounted on wheels 4, to which a first working arm 5 is fixed at a front zone and at least a second working arm 6 is fixed at a rear zone.

At an intermediate portion of the chassis 3 there is also a cab 7 enclosing the control position 1.

Only the main parts of the control position 1, representing the core of the present invention, are illustrated in Figures 1 to 7. The other parts, such as the steering column connected to the steering wheel 8 and the fixed dashboards have been removed for greater clarity.

The control position 1 comprises first a seat 9 for the operator, which can be rotated about a first axis of rotation between a front position in which it is facing the first working arm 5 (Figure 1) and a rear position in which it is facing the second working arm 6 (Figure 6). In practice, when the machine is positioned on flat terrain, the first axis of rotation extends vertically.

In front of the seat 9, when it is in the front position, there are means for driving the backhoe loader 2, comprising, amongst other things, the steering wheel 8. The accompanying drawings do not illustrate the steering column connected to the steering wheel 8, or the front dashboard (where the normal additional devices for backhoe loader 2 check and control during movement are positioned), or the mechanisms which allow the position of the steering wheel to be adjusted (height and depth), since they are of the known type. In contrast, the steering wheel preferably has a shape such that it does not interfere with seat rotation. In the accompanying drawings this is achieved with a shape that, with the steering wheel in the neutral position (illustrated in the accompanying drawings) has a lower central transversal body, to which the steering column is connected, and two lateral handgrips extending upwards on the two sides of the lower transversal body. Unlike traditional spoke steering wheels, it is therefore without portions extending downwards relative to the central band for connection to the steering column. For more information about the shape of the steering wheel 8 reference may be made to the parallel PCT patent application relating to it, incorporated here as a reference. In the control position 1 there are both first operating means 10 for the first working arm 5, which the operator can operate while sitting on the seat 9 located in the front position, and second operating means 11 for the second working arm 6 which the operator can operate while sitting on the seat 9 located in the rear position. Moreover, in accordance with the present invention, at least part of the second operating means 11 are mounted on a control console 12 positioned close to the seat 9, and which can move between a lateral position in which it is at the side of the seat 9 located in the front position (Figures 1 and 2), and an operating position in which it is in front of the seat 9 located in the rear position (Figures 5 and 6).

In particular, when the control console 12 is in the operating position, the operator can operate the second operating means 11 while sitting on the seat 9 located in its rear position.

Moreover, advantageously, the control position 1 also comprises synchronisation means (not illustrated in detail) for causing the movement of the control console 12 from the lateral position to the operating position and vice versa, following seat 9 rotation from the front position to the rear position and vice versa. Depending on requirements, said synchronisation means may be purely mechanical (for example suitable gears), electromechanical, hydraulic, etc. Moreover, in the embodiment illustrated, to allow control console 12 movement from the lateral position to the operating position and vice versa, there are means 13 for rotating the control console 12, at least about a second axis of rotation parallel with the first axis of rotation.

Advantageously, the synchronisation means and the rotation means 13 are made in such a way that they cause the control console 12 to rotate in the opposite direction to the seat 9 (Figures 2 to 5). It should also be noticed that for a seat 9 rotation through 180° there is a control console 12 rotation of only 90°.

The rotation means 13 may for example consist of an electric motor or a gear. Consequently, the relative synchronisation means may consist respectively of a sensor which detects the position of the seat 9 and an electronic control system for the electric motor, or of a gear connected to that of the rotation means 13.

Figures 8 to 17 illustrate in detail the system for moving the control console 12 adopted in the embodiment illustrated. In said figures, for greater clarity, the seat 9 is not illustrated but only part of its supporting shaft 14 is visible (able to rotate about the first axis of rotation). As can be seen, first both the control console 12 and the seat 9 are preferably supported by the same support 15 which, advantageously, is cushioned and height- adjustable (similarly to prior art seat supports).

The connection between the seat 9 and the support 15 is made with a shaped rigid flange 16 (Figure 14) extending from part of the edge of the upper face 17 of the support 15 to a zone located above the support 15 at a predetermined distance from its upper face 17, where it forms the seat 9 rotation housing 20. The first axis of rotation formed by said housing 20 passes through the upper face 17 of the support 15 substantially at the centre. hi particular, the flange 16 consists of two portions: a first portion 18 extending parallel with the first axis of rotation and having the shape of a circular arc in plan view, and a second portion 19 having the shape of part of a truncated cone wall. The base of the second portion 19 is connected to the first portion 18 and the top of the second portion is connected to the seat 9 rotation housing 20 (Figure 16).

The seat 9 shaft 14 extends, through the rotation housing 20, also partly in the space between the housing 20 itself and the upper face 17 of the support 15.

In the preferred embodiment of the present invention, the control console 12 rotation means 13 also rotate about the first axis of rotation together with the seat 9. In the accompanying drawings this is achieved with a bracket 21 integral with the seat 9 (and in particular with the lower portion of its shaft 14), extending radially relative to the first axis of rotation. As Figure 15 shows, the bracket 21 comprises two parallel tabs forming two guides 22 on which the control console

12 rotation means 13 are slidably mounted so that they can slide along a sliding direction substantially radial relative to the first axis of rotation.

For this purpose, the rotation means 13 comprise a first part 23 integral with the bracket 21 (relative to which it can slide but not rotate), and a second part 24 rotatably connected to the first part 23, to which the control console 12 is fixed.

Moreover, in the accompanying drawings the rotation means 13 are also guided in their movement along the bracket 21 by the sliding of the first part 23 in a first straight channel 25 rotatably associated with the upper face 17 of the support 15. Rotation of the first channel 25 relative to the support 15 is in turn guided by a tooth (not visible) integral with the lower part of the first channel 25 and slidably inserted in a second channel 26 having the shape of a circular arc, made in the upper face 17 of the support 15.

Moreover, in the preferred embodiment, the control position 1 also comprises means 27 for translating the control console 12 relative to the seat 9 at least in a plane perpendicular to the first axis of rotation.

In the accompanying drawings, the translation means 27 comprise a horizontal shaped bar 28 (that is to say, lying in the plane perpendicular to the first axis of rotation) slidably inserted in a guide element 29 rigidly connected to the rotation means 13 (in particular, the guide element 29, which is substantially L- shaped, is connected to the second part 24 of the rotation means 13). Extending upwards from the bar 28 there is a tower assembly 30 connected to the upper portion 31 of the control console 12.

Depending on requirements, the translation means 27 may also allow the control console 12 to move in a direction perpendicular to the direction of extension of the sliding bar 28.

The upper portion 31 of the control console 12 has an extended shape and, in the control console 12 operating position, is located transversally in front of the seat 9 (located in the rear position). The second operating means 11 are also mounted on the upper portion 31.

The seat 9 can also be translated (with methods similar to prior art ones, therefore not illustrated in detail) in a plane perpendicular to the first axis of rotation according to a forward - back direction (that is to say, along a direction substantially perpendicular to the backrest) which, when the seat 9 is in the front and rear position, corresponds to the direction of longitudinal extension of the backhoe loader 2.

Advantageously, the control position 1 also comprises means 32 for selectively hooking the control console 12 to the seat 9 to translate the control console 12 together with the seat 9. In particular, this may be achieved by translating, together with the seat 9, the rotation means 13 to which the control console 12 is connected. hi the embodiment illustrated, the selective hooking means 32 act only when the seat 9 is in the rear position and the control console 12 is in the operating position or when the seat 9 is in the front position and the control console 12 is in the lateral position.

They comprise a hooking element 33 integral with the seat 9 able to slidably associate with two elements 34, shaped to match it, which are integral with the control console 12, and in particular one with the guide element 29 and the other with the bar 28 (Figures 18 and 21). Since the direction of hooking and release of the selective hooking means 32 is perpendicular to the direction of seat 9 movement (that is to say, substantially parallel with the seat 9 backrest), the forward - backwards movement of the seat 9 causes translation of the rotation means 13 relative to the bracket 21.

In other words, the direction of hooking and release is at a tangent to the first axis of rotation, so that hooking and release occur simply by means of rotation of the seat 9 and the control console 12.

Suitable devices, not illustrated, allow fixing of the seat 9 position as required, and therefore of the rotation means 13, to adapt the control position 1 to users who have different builds.

Figure 18 shows the case of the seat 9 in the front position and the control console 12 in the lateral position, two three-dimensional arrows F indicating that the seat 9 is moved forward. The result of this translation is visible in Figure 19 which shows that the control console 12, with its rotation means 13, is also moved together with the seat 9 (which reached the forward limit position).

Figure 20 illustrates the case of the seat 9 in the rear position and the control console 12 in the operating position. Again, two three-dimensional arrows F indicate the movement of the seat 9, which this time is moved back (back relative to the support 15, but towards the front part of the backhoe loader 2). The result of this translation is visible in Figure 19 which shows that the control console 12, with its rotation means 13, also moved together with the seat 9 (which reached the back limit position).

Depending on the position of the seat 9 and the rotation means 13 relative to their support 15, the control position 1 movement dynamics vary slightly.

Figures 8 to 12 show the case in which the movement occurs with the seat 9 completely forward. In this case, during rotation, the second axis of rotation is eccentric relative to the first axis of rotation.

Figure 13 shows the opposite case (seat 9 completely back). In this case, during rotation, the second axis of rotation coincides with the first axis of rotation.

Finally, Figures 14 to 17 show the case of the seat 9 in an intermediate position. In this case, the second axis of rotation is eccentric relative to the first axis, but less so than in the case illustrated in Figures 8 to 12. hi the preferred embodiment, the present invention also has the first operating means 10 at least partly mounted on the control console 12, so that when the control console 12 is in the lateral position, these first operating means can be operated by an operator sitting on the seat 9 in the front position.

In the embodiment illustrated, in particular, the first operating means 10 and the second operating means 11 share several control 35 and check devices (Figure 21) which, depending on the position of the control console 12, perform functions relative to the first operating means 10 or the second operating means 11. For this purpose, suitable switching means (not illustrated) connect the control device 35 to the first operating means 10 when the control console 12 is in the lateral position, and to the second operating means 11 when the control console 12 is in the operating position.

In particular, Figure 1 shows a controller 36, a screen 37 and several pushbuttons 38 shared by the first and second operating means 10, 11. In the embodiment illustrated, the controllers consist of fixed handgrips equipped, at the bend in the L, with a push-button that can be operated in multiple directions, with which the various machine movements are associated. For more information about said controllers reference may be made to the parallel PCT patent application relating to them, incorporated here as a reference.

Moreover, as shown, since the controller 36 must be gripped with the right hand when the control console 12 is in the lateral position and with the left hand when the control console 12 is in the rear position, it has advantageously been made symmetrical in the shape of an L so that it can be gripped in the same way in both cases.

As regards use of the backhoe loader 2 which is the subject matter of the present invention, Figure 1 shows the control position 1 in the condition for use of the loading shovel. The control console 12, in the lateral position, is close to the seat 9 so that the controller 36 located close to the screen 37 is aligned with the seat 9 armrest 40.

In contrast, Figure 2 shows the configuration for driving on the road, with the control console 12 moved laterally relative to the seat 9, so that it does not hinder the operator's movements while driving.

The control console 12 is moved between the two positions illustrated in

Figures 1 and 2 by the translation means 27, and in particular by sliding of the bar

28 relative to the guide element 29. Suitable means, not illustrated, controlled for example by a push-button 39 on the control console 12, allow the control console 12 to be locked and released in the positions shown in Figures 1 and 2.

The operating condition in Figure 2 is the starting point for switching the control position 1 to the configuration for controlling the second working arm 6.

The seat 9 is simply rotated (anti-clockwise in the accompanying drawings), after releasing it, so that the synchronisation means cause a simultaneous counter- rotation of the control console 12 (clockwise in the accompanying drawings).

When the seat 9 reaches the rear position, the control console 12 is in the operating position but distanced from the seat 9 (Figure 5). At that point the operator can move the entire control console 12 closer to position the controllers

36 at the correct distance from the armrests 40. Again, the control console 12 is moved by sliding of the bar 28 in the guide element 29. Whilst in Figure 1 the bar 28 extends transversally to the longitudinal direction of the backhoe loader, in Figure 6 it extends parallel with said longitudinal direction.

In Figures 1 to 7, the control position 1 movement is represented with the seat 9 in the back limit position (with reference to its front position and to the front and rear parts of the backhoe loader), that is to say, in the rotation means 13 configuration illustrated in Figure 13.

In contrast, Figures 8 to 12, as already indicated, show the opposite case (seat 9 completely forward), whilst Figures 14 to 17 show an intermediate case.

Finally, it should be noticed that the configurations of Figures 8 and 14 correspond to the layout of Figure 1, that of Figure 9 to the layout of Figure 2, those of Figures 10 and 15 substantially to the layout of Figures 3 and 7, that of

Figures 13 and 16 substantially to the layout of Figure 4, that of Figure 11 to the layout of Figure 5, and those of Figures 12 and 17 to the layout of Figure 6.

The present invention brings important advantages. Firstly, a backhoe loader made in accordance with the present invention has a control position in which switching from the driving or loading shovel use condition to the condition for use of the rear arm is extremely easy and ergonomic because it requires minimum movements and effort by the operator, and guarantees that there is no interference between the operator's body and parts of the control position during use. Moreover, the control position allows perfect adaptation of every part to the build of each operator.

Secondly, thanks to rotation of the control console, in the position for operation with the backhoe lateral visibility is also improved.

Moreover, thanks to the use of the above-mentioned switching means, it was possible to reduce the number of components used, since the same components have become dual-purpose, that is to say, able to be used both during use of the loading shovel and use of the backhoe. This is the opposite of what happens in conventional machines, where many components remain unused for most of the time. It should also be noticed that the present invention is relatively easy to produce and even the cost linked to implementation of the invention is not very high.

The invention described above may be modified and adapted in several ways without thereby departing from the scope of the inventive concept. All details of the invention may be substituted by other technically equivalent elements and, in practice, all of the materials used, as well as the shapes and dimensions of the various components, may be any according to requirements.

Claims

1. A backhoe loader having a chassis (3) on which there are mounted at least a first working arm (5) at a front zone, at least a second working arm (6) at a rear zone, and a control position (1), comprising: a seat (9) able to rotate about a first axis of rotation between a front position in which it is facing the first working arm (5) and a rear position in which it is facing the second working arm (6); means for driving the backhoe loader (2) positioned in front of the seat (9) located in the front position; at least one control console (12) positioned close to the seat (9); first operating means (10) for the first working arm (5) which can be operated by an operator sitting on the seat (9) located in the front position; and second operating means (11) for the second working arm (6) which can be operated by an operator sitting on the seat (9) located in the rear position, at least part of the second operating means (11) being mounted on the control console (12); the backhoe loader being characterised in that the control console (12) can move between a lateral position in which it is at the side of the seat (9) located in the front position, and an operating position in which it is in front of the seat (9) located in the rear position, so that the second operating means (11) can be operated by an operator sitting on the seat (9) in its rear position.

2. The backhoe loader according to claim 1, characterised in that the control position (1) also comprises synchronisation means for causing the movement of the control console (12) from the lateral position to the operating position and vice versa, following seat (9) rotation from the front position to the rear position and vice versa.

3. The backhoe loader according to claim 1 or 2, characterised in that it also comprises means (13) for rotating the control console (12) from the lateral position to the operating position, at least about a second axis of rotation parallel with the first axis of rotation.

4. The backhoe loader according to claims 2 and 3, characterised in that the synchronisation and rotation means cause the control console (12) to rotate in the opposite direction to the seat (9).

5. The backhoe loader according to claim 3 or 4, characterised in that the rotation means (13) also rotate about the first axis of rotation together with the seat (9).

6. The backhoe loader according to claim 5, characterised in that the control position (1) also comprises a bracket (21) integral with the seat (9) and in that the rotation means (13) are slidably associated with the bracket (21) according to a direction of sliding substantially radial relative to the first axis of rotation.

7. The backhoe loader according to any of the foregoing claims, characterised in that it also comprises means (27) for translating the control console (12) relative to the seat (9) at least in a plane perpendicular to the first axis of rotation.

8. The backhoe loader according to any of the foregoing claims, characterised in that the seat (9) can also translate in a plane perpendicular to the first axis of rotation.

9. The backhoe loader according to claim 8, characterised in that it also comprises means (32) for selectively hooking the control console (12) to the seat (9) for translating the control console (12) together with the seat (9).

10. The backhoe loader according to claim 9, characterised in that the selective hooking means (32) act at least when the seat (9) is in the rear position and the control console (12) is in the operating position and/or when the seat (9) is in the front position and the control console (12) is in the lateral position.

11. The backhoe loader according to any of the foregoing claims, characterised in that the control console (12) has an upper portion (31) having an extended shape which in the control console (12) operating position is located transversally in front of the seat (9) located in the rear position.

12. The backhoe loader according to any of the foregoing claims, characterised in that the control console (12) and the seat (9) are both supported by the same support (15).

13. The backhoe loader according to claim 12, characterised in that the support (15) is also cushioned and height-adjustable.

14. The backhoe loader according to any of the foregoing claims, characterised in that the first operating means (10) are also at least partly mounted on the control console (12).

15. The backhoe loader according to claim 14, characterised in that the first operating means (10) can be operated by an operator sitting on the seat (9) in the front position, when the control console (12) is in the lateral position.

16. The backhoe loader according to claim 15, characterised in that the control console (12) comprises at least one control device (35) which can be operated by an operator and means for switching the functions of the control device (35) according to the position of the control console (12), said switching means connecting the control device (35) to the first operating means (10) when the control console (12) is in the lateral position, and to the second operating means (11) when the control console (12) is in the operating position.

17. The backhoe loader according to claim 16, characterised in that the switching means act on a plurality of control (35) and check devices to connect them respectively to the first and second operating means (11) when the control console (12) is respectively in the lateral position or in the operating position.