FR3131333A1 - Improved device for converting the horizontal angular displacement of a boom of an earth-moving machine - Google Patents

Abstract

Title: Horizontal angular displacement conversion sensor device of an earth-moving machine boom and earth-moving machine comprising such a device. The invention relates to a sensor device for converting the horizontal angular displacement of a boom (14) of an earth-moving machine (1), as well as an earth-moving machine comprising such a device. This device comprises a sensor support (25) comprising: - a transmitting part (21) intended to be fixedly mounted on a part of the boom (14), - a mechanical transmission (27) configured to transmit to a receiving part (21A ) a horizontal angular displacement of said transmitting part (21) relative to a frame (4) around a first axis (B), said receiving part (21A) then being moved angularly around a second axis (A) perpendicular to the first axis (B); - the sensor support (25) being configured to receive at least one sensor (38), of the gravity and/or accelerometer type, designed to measure said angular displacement of the receiving part (21A) around the second axis (A), - said sensor support (25) being mounted integral with the frame (4) and in rotation about the first axis (B). Abstract Figure: Fig. 4

Description

Improved device for converting the horizontal angular displacement of a boom of an earth-moving machine

The present invention belongs to the technical field of guiding earth-moving machinery, for example mechanical excavators used for excavation, digging, earthmoving, embankment, etc. The invention applies in particular to hydraulic excavators, equipped with an arm having an offset at the level of the boom foot or part of the boom.

The invention relates more particularly to an angular displacement conversion device intended to be mounted on a boom of such an earth-moving machine and in particular of a hydraulic excavator, preferably an excavator having a boom offset, to measure an angular displacement vertical, but also a horizontal angular movement of the boom on the hydraulic excavator.

The invention secondary aims at an earth-moving machine equipped with such an angular displacement conversion device.

STATE OF PRIOR ART

A standard excavator, used for jobs such as digging, excavation or backfilling, includes an articulated arm broadly mimicking the movement of a human arm. This articulated arm ends in a bucket, suitable for digging land. The articulated arm is connected to the turret. The latter includes a cabin in which the driver is positioned and from which he controls the movement of the arm. An articulated arm of a hydraulic excavator generally includes a “boom” connected, at one end, to the turret, while on the opposite end of this boom is mounted, articulated, the end of a “dipper”. The bucket is placed at the opposite end of this pendulum.

The boom and the balance are generally actuated by respective hydraulic cylinders, in particular in rotation around their joints. In the field of mechanical excavators, we know in particular arms with a one-piece boom or a variable-fly boom, with or without boom offset.

From the turret mounted on the chassis, the driver generally has a guidance system (comprising for example a dashboard) allowing him to know several arm position parameters, such as the position of the bucket, the inclination of the dipper stick. , or the inclination of the arrow. The driver has access to these measurements from inside the turret, which limits the driver's dependence on ground crews to receive information in real time.

Known excavator guidance systems may include angular movement sensors attached to the boom, to the bucket, etc. these sensors make it possible to measure a vertical angular displacement of the different portions of the arm relative to the chassis, or relative to a portion of the boom, etc. The information acquired by these sensors can be transcribed on the dashboard in the cabin. Guidance is for example carried out by GPS (“Global Positioning System”).

The boom of the arm of a hydraulic excavator is mounted by means of a boom foot on the turret, generally near the cabin, in an articulated manner around a horizontal axis. In certain cases, this boom is also pivotable around a vertical axis at this end secured to the turret via a boom foot.

The driver thus has an additional degree of freedom to move the arm and the bucket without changing its trajectory. We then speak of a “boom offset” excavator, the boom foot and its joint being offset in relation to the turret. In such an architecture, the boom foot has more mobility with respect to the turret and the rest of the chassis of the hydraulic excavator. Hydraulic excavators on the market, weighing less than 25 tonnes, often have such a boom offset.

In an excavator equipped with a boom offset, the boom can pivot relative to the chassis of the excavator, not only vertically (around an axis of rotation substantially parallel to the ground) but also horizontally (around an axis of rotation substantially orthogonal to the ground). To know the position and inclination of the arrow, it is therefore necessary to measure the angular displacement in real time in these two directions.

To provide these angle measurements, it has been proposed to equip the boom arm with a plurality of angular sensors, capable of positioning the bucket in relation to at least one other GNSS type sensor ("Global Navigation Satellite Systems" ) allowing real-time geolocation of the bucket. For example, an angular sensor, called gravity, of the heated air bubble type, operating by gravity, is used for this purpose. However, such gravity sensors cannot determine a horizontal angular displacement, that is to say by rotation around a vertical axis.

Accelerometer type sensors are also used, but they are not suitable for slow movements during which they tend to drift, so that they must be readjusted each time.

To the Applicant's knowledge, there is therefore currently no simple, space-saving and inexpensive system adaptable to an excavator with a boom offset, for measuring the horizontal angular displacement of the boom relative to the chassis.

GENERAL DESCRIPTION OF THE INVENTION

A first objective of the invention is to propose a system for guiding the arm of an earth-moving machine making it possible to respond to the problems raised above, and which is in particular better suited to controlling the position of the arm of an offset excavator. of arrow.

An additional objective is to provide a machine incorporating a device for converting the horizontal angular displacement of the arrow around a substantially vertical axis of rotation (angular displacement which is therefore carried out horizontally). Combined with an angular measurement sensor, this conversion device must allow precise measurement, little sensitive to the vibrations of the excavator and little sensitive to wear of the ring surrounding the vertical axis of rotation of the boom.

This device is also desired to be compact and not bulky, so as to easily adapt to any type of hydraulic excavator.

Another objective is to propose an arrow displacement measuring device which is inexpensive and simple to manufacture, particularly with regard to the angular sensor(s). We preferentially wish to reuse the same type of angular sensor which is already usually used to measure the movement of an arrow and/or a beam and/or a bucket and/or a turret along the pitch axis or according to the roll axis.

To meet these objectives, a first aspect of the invention relates to a sensor device for converting horizontal angular displacement of an arrow of an earth-moving machine, said device being intended to be carried on the earth-moving machine and comprising a sensor support comprising:

- a transmitter part intended to be fixedly mounted on a part (16) of the boom;

- a mechanical transmission configured to transmit to a receiving part a horizontal angular movement of said transmitting part relative to a frame around a first axis, said receiving part then being moved angularly around a second axis perpendicular to the first axis;

- the sensor support being configured to receive at least one sensor, of the gravity and/or accelerometer type, designed to measure said angular displacement of the receiving part around the second axis,

- said sensor support being mounted integral with the frame and rotating around the first axis.

An angular displacement conversion device as defined above can, optionally and without limiting the definition of the invention, have the following characteristics taken alone or in combination:

According to a second aspect, the present invention relates to an earth-moving machine comprising a frame and a boom comprising a boom foot movable relative to said frame, said machine preferably being a hydraulic excavator, said machine further comprising a conversion device such as defined above, comprising an angular movement sensor for measuring a movement of the arrow relative to the frame around an axis, and further comprising a support secured to the frame, the angular movement sensor being mounted on said support.

GENERAL DESCRIPTION OF THE FIGURES

• La représente une pelle hydraulique à déport de flèche montée sur des chenilles, vue de profil.
• La illustre schématiquement un dispositif de conversion de déplacement angulaire horizontal de flèche selon un premier exemple de réalisation, le dispositif de conversion étant monté sur une pelle hydraulique à déport de flèche, le dispositif étant vu de côté.
• La illustre schématiquement le même dispositif de conversion, vu du côté.
• La est une vue schématique de côté d’un dispositif de conversion de déplacement angulaire horizontal de flèche selon un second exemple de réalisation ;
• La est une vue schématique de face de la ;
• La est une vue schématique en coupe de la ;
• La est une vue similaire à la d’un dispositif de conversion selon un troisième exemple de réalisation.

Other objectives and advantages of the invention will emerge from reading the description below, given by way of illustration and not limitation, this description being supplemented by the appended figures among which:

• There represents a hydraulic excavator with boom offset mounted on tracks, side view.
• There schematically illustrates a device for converting horizontal angular displacement of the boom according to a first embodiment, the conversion device being mounted on a hydraulic excavator with boom offset, the device being seen from the side.
• There schematically illustrates the same conversion device, seen from the side.
• There is a schematic side view of a device for converting horizontal angular displacement of an arrow according to a second exemplary embodiment;
• There is a schematic front view of the ;
• There is a schematic sectional view of the ;
• There is a view similar to the of a conversion device according to a third embodiment.

DESCRIPTION OF AN EXAMPLE OF WORK

In reference to the , we have shown a hydraulic excavator 1 according to an example. The excavator 1 comprises a chassis 2, mounted on rolling means 3, of the caterpillar or wheel type. On this chassis 2 is mounted in rotation around a vertical axis a turret, also called frame 4, surmounted by a cabin 5 accommodating a cockpit for the driver. On this turret 4 is still fixed an articulated arm 6.

More particularly, the articulated arm 6 comprises a balance wheel 7, a first free end 8 of which is equipped, by means of an articulation 9, with a tool 10, here represented in the form of a bucket, at least rotatable around a horizontal axis. At its second end 11 and thanks to an articulation 12, this balance 7 is pivotally mounted around a horizontal axis of rotation on a first end 13 of an arrow 14 whose second opposite end 15 is articulated around a horizontal axis on a boom foot 16, this using a joint 17.

It should be observed that the boom 14 can be composed of a first boom member connected to the boom foot 16 and extended through an articulation by a second boom member receiving the balance 7, a configuration which is not shown in the drawings.

Thus, the articulated arm 6 can have an articulation 9 between the bucket 10 and the balance beam 7, an articulation 12 between the balance beam 7 and the boom 14 (or even between a first and a second boom member), and an articulation 17 between this boom 14 and the boom foot 17. The different parts are articulated together, for example, by a respective hydraulic cylinder.

In the case of a so-called “boom offset” hydraulic excavator, this boom offset 18 can occur at the level of the boom foot 16. This can itself be secured to the turret or frame 4 through a joint 19 axis of vertical rotation.

In the embodiment not shown and already mentioned above, this boom offset is defined by an axis of articulation between the first member and the second member of a boom in two parts.

In the case of an offset of boom 18 at the boom foot 16, this is in the form of a yoke partly designing this articulation 19.

• un premier axe B sensiblement vertical, passant par l’articulation 19 du pied de flèche 16 sur cette tourelle ou bâti 4 (qui correspond à un déplacement angulaire horizontal de la flèche 14 parallèlement au sol) ;
• un deuxième axe passant par l’articulation 17, ici perpendiculaire au premier axe B, ledit axe étant sensiblement parallèle à la surface du sol et passant par le pied de flèche 16 (qui correspond à un déplacement angulaire vertical de la flèche 14 perpendiculairement au sol).

This design results in the arrow 14 being movable in rotation relative to the turret or frame 4, mainly around the following two perpendicular axes:

• a first substantially vertical axis B, passing through the articulation 19 of the boom foot 16 on this turret or frame 4 (which corresponds to a horizontal angular movement of the boom 14 parallel to the ground);
• a second axis passing through the articulation 17, here perpendicular to the first axis B, said axis being substantially parallel to the surface of the ground and passing through the boom foot 16 (which corresponds to a vertical angular movement of the boom 14 perpendicular to the ground ).

In the case where the boom 14 comprises a first boom member articulated with a second boom member carrying the balance, the second boom member can also undergo angular displacement, for example horizontal, relative to the boom base.

For illustration purposes, we have shown on the the position of an axis C around which the second boom member can be movable in rotation relative to the first boom member.

A device 20 for converting the angular displacement of the boom 14 is described below. The device 20 makes it possible to convert into vertical angular displacement the horizontal angular displacement of the boom 14 around the axis B relative to the turret or frame 4 This device 20 is illustrated in different embodiments in Figures 2 to 7 . It is intended to be loaded on the boom 14, for example on the boom foot 16.

Alternatively, this conversion device 20 could be used on another type of earth-moving machine.

The device 20 comprises a sensor support 25 (described further below) comprising a transmitter part 21 which follows the horizontal angular movement of the arrow 14. For example, the transmitter part 21 comprises a vertical shaft in the form of a hinge 22 mounted by welding or through a base 23 on the jib base 16, preferably in the axial extension of the vertical pivot axis B (for horizontal movement) of this jib base 16 relative to the turret or frame 4.

On this shaft 22 is engaged, free to rotate and by means of a bearing 30, a first horizontal wing 24 of a bracket 25 integrally connected to the turret or frame 4. Consequently, when the jib foot 16 rotates relative to to the turret 4 around the vertical pivot axis B defined by the articulation 19 which connects it to this turret 4, the horizontal wing 24 of the bracket 25 pivots around the shaft 22.

More particularly, this bracket 25 defines at least in part the sensor support included in the conversion device according to the invention. In particular, as shown in Figures 2 to 7, the sensor support can take the form of a box including two 24; 24A perpendicular walls design square 25.

It will be noted that in an alternative example where the arrow 14 would present a first and second arrow member articulated together around an axis C (as illustrated in the ), the transmitter part 21 could be mounted on one end of the second boom member, to follow its angular movement around the axis C relative to the first boom member.

According to a first embodiment corresponding to Figures 2 and 3, the transmitter part 21 comprises at least one driving disk 26 mounted integrally in rotation on the shaft 22 to transmit the horizontal angular displacement around the axis B (or around the axis C in the alternative example mentioned above). This driving disc 26 belongs to a mechanical transmission 27.

This also includes at least one driven disk 28 of a receiving part 21A, placed on the other side of the transmission 27. This driven disk 28 is mounted integrally in rotation on a shaft 29 of the receiving part 21A, this shaft 29 being mounted free to rotate around a horizontal axis using a bearing 30A on the second wing 24A, perpendicular to the first wing 24, of the bracket 25.

The mechanical transmission 27 also comprises a direct transmission element 31, transmitting the movement of the driving disk 26 to the driven disk 28. In this first example, the transmission element 31 comprises at least one link 32; 33 connected by means of articulations to the driving disk 26, on the one hand, and to the driven disk 28, on the other hand, so that a rotation of the first disk 26 around the vertical axis B corresponding to a horizontal movement, generates a rotation of the second disk 28 around the horizontal axis A, corresponding to a vertical movement.

Such an embodiment, however, leads to movements of these discs 26 and 28 which are not proportional to the horizontal angular movement of the arrow 14, but rather exponential.

As illustrated in Figures 4, 5 and 6 applying to a second embodiment, the discs 26, 28, respectively of the transmitter part 21 and the receiver part 21A, can be replaced, respectively, by a pulley trainer 26A and a pulley driven 28A and the transmission element 31 by a belt 32A. This partially wraps around these pulleys 26A; 28A by bypassing a return roller 34 whose axis 35 extends perpendicular to the plane passing through the axes A and B, this to return the strands of this belt 32A, from horizontal directions of movement around the driving pulley 26A, in vertical directions of movement around the driven polish 28A.

We understand that instead of a belt, a cable and/or a rope can be used.

There illustrates a third embodiment in which the mechanical transmission 27 takes the form of a bevel gear 36, comprising, at the level of the transmitting part 21, a driving wheel with conical teeth 26B mounted integrally in rotation on the shaft 22 and in direct drive with a driven wheel with conical teeth 28B mounted integrally in rotation on the shaft 29 of the receiving part 21A.

A horizontal angular movement of the arrow 14 around the axis B is thus transmitted, via the mechanical transmission 27, whatever its form of embodiment, from the emitting part 21 to the receiving part 21A which then produces a vertical angular movement around of axis A.

The angular conversion device 1 is provided with a receiving base 37 configured to receive an angular movement sensor 38 from the receiving part 21A. The receiving base 37 has for example a general disc shape, or alternatively a general rectangular shape. It is mounted integrally in rotation on the shaft 29 of this receiving part 21A. Thus, relative to the second vertical wing 26A of the bracket 25, this receiving base 37 can be located on this shaft 29, either on the side, depending on the case, of the driven disc 26, of the driven pulley 26A or of the driven bevel wheel 26B, or on the opposite side (preferred solution and illustrated in the figures). It will be noted that the sensor 38 can be removably mounted on this receiving base 37.

Once positioned on the receiving base 37, it is configured to measure the vertical angular displacement of the receiving part 21A relative to the transmitting part 21 and therefore of the turret or frame 4. A measurement frequency of the movement sensor 38 angular is for example between 50 Hertz and 150 Hertz, for example equal to 100 Hertz.

An important advantage of the device 1 is to make it possible, for the measurement of the horizontal angular displacement, the use of a standard sensor 38, of the gravity and/or accelerometer type, as usually implemented to measure a vertical angular displacement d 'a shovel arrow. The sensor 38 is for example an angular hot air bubble sensor operating by gravity.

The conversion device 1, associated with such a sensor, thus makes it possible to measure a horizontal angular displacement of the excavator boom, and we can do without a complex sensor which would be specifically dedicated to this purpose.

An additional advantage is that the precision of the horizontal angular displacement perceived by this device is not affected by any play, which could exist at the level of the articulation 19 of the boom foot 16 on the turret or frame 4.

As explained above, the sensor support 25 is mounted in rotation on the shaft 22 with its axis coinciding with the axis B, corresponding to the axis of rotation of the jib base 16 relative to the frame 4, in l occurrence of the turret. Furthermore, this sensor support 25 is fixed relative to the frame 4. In this regard, any connecting means 39 capable of fixing this sensor support 25 in rotation relative to the frame 4 can be implemented. In Figures 3 and 5 we see secured to the sensor support 25 a threaded rod defining at least partly this connecting means. However, it can take many other forms.

It should also be noted that the conversion device can be equipped with remote communication means and/or wired connection means to transmit information from the sensor 38 towards a management unit, for example installed at the level of the cockpit 5 and communicating with display means capable of informing the driver of the angular position of the arrow 14 around the axis B. These display means can be those intended to give this driver other altimetric information of the position of the tool 10.

Claims (11)

Sensor device for converting horizontal angular displacement of a boom (14) of an earth-moving machine (1), said device being intended to be carried on the earth-moving machine (1) and comprising a sensor support (25 ) comprising:
- a transmitter part (21) intended to be fixedly mounted on a part of the boom (14),
- a mechanical transmission (27) configured to transmit to a receiving part (21A) a horizontal angular movement of said transmitting part (21) relative to a frame (4) around a first axis (B), said receiving part ( 21A) then being moved angularly around a second axis (A) perpendicular to the first axis (B);
- the sensor support (25) being configured to receive at least one sensor (38), of the gravity and/or accelerometer type, designed to measure said angular displacement of the receiving part (21A) around the second axis (A),
- said sensor support (25) being mounted integral with the frame (4) and rotating around the first axis (B). Conversion device according to claim 1, characterized in that the transmitting part (21) comprises a vertical shaft in the form of a hinge (22) mounted by welding or through a base (23) on a part (16) of the arrow (16), on this shaft (22) being engaged, free to rotate, a first horizontal wing (24) of a bracket (25) integrally connected to the frame (4) and comprising a second wing (24A), perpendicular to the first (24), on which is mounted free to rotate around a horizontal axis on a shaft (29) of the receiving part (21A). Conversion device according to claims 1 and 2, characterized in that the transmitting part (21) comprises at least one driving disk (26) mounted integrally in rotation on the shaft (22) to transmit the horizontal angular displacement around the axis (B) to a driven disk (28) of the receiving part (21A), the mechanical transmission (27) comprising a direct transmission element (31) in the form of at least one link (32; 33) connected thanks to articulations to the driving disk (26), on the one hand, and to the driven disk (28), on the other hand, so that a rotation of the driving disk (26) around the vertical axis (B), generates a rotation of the driven disk (28) around the horizontal axis (A). Conversion device according to claims 1 and 2, characterized in that the transmitting part (21) comprises at least one driving pulley (26A) mounted integrally in rotation on the shaft (22) to transmit the horizontal angular displacement around the axis (B) to a driven pulley (28A) of the receiving part (21A), the mechanical transmission (27) comprising a direct transmission element (31) in the form of a belt (32A) coming to partially wind around these pulleys (26A; 28A) bypassing a return roller (34) whose axis (35) extends perpendicular to the plane passing through the axes (A) and (B). Conversion device according to claims 1 and 2, characterized in that the mechanical transmission (27) takes the form of a bevel gear (36), comprising, at the transmitting part (21), a driving wheel with conical teeth (26B) mounted integrally in rotation on the shaft (22) and in direct connection with a driven wheel with conical teeth (28B) mounted integrally in rotation on the shaft (29) of the receiving part (21A). Conversion device according to one of the preceding claims, characterized in that the sensor support (25) comprises a receiving base (37), configured to receive a sensor (38) of angular movement of the receiving part ( 21A). Conversion device according to claim 6, characterized in that the receiving base (37) has a general disc shape, or alternatively a generally rectangular shape and is mounted integrally in rotation on the shaft (29) of the receiving part (21A). Conversion device according to claim 7, characterized in that relative to the second vertical wing (26A) of the bracket (25), the receiving base (37) is located on the shaft (29), i.e. from side of the driven disc (26), the driven pulley (26A) or the driven bevel gear (26B), or on the opposite side. Conversion device according to one of claims 6 to 8, characterized in that the sensor (38) can be removably mounted on the receiving base (37). Earth-moving machine comprising a frame (4), and a boom (14) comprising a boom foot (16) movable in rotation around a vertical axis (B) relative to the frame (4), the machine preferably being a hydraulic excavator, the machine further comprising:
- an angular displacement conversion device (1) according to any one of claims 1 to 9. Earth-moving machine according to claim 10, in which the device (1) is placed on the boom foot (16) and the emitting part (21) is made integral with the latter.