FR2736370A1 - Trench cutting implement for cable or pipe laying - incorporates system for removing excavated material made from two inclined scrapers - Google Patents

Abstract

The implement consists of a cutting wheel (3) with cutting bits (10) round its rim, a wheel support (4) in the shape of a stirrup, and a drive (6A) which is mounted on the stirrup. It also has a system (12) for removing the material which is excavated from the trench, connected to front of the support (4) where the material emerges from the trench, and comprising two scrapers which are inclined relative to the peripheral surface of the wheel rim and located symmetrically relative to the wheel's median plane. The removal system (12) is adjustable relative to the wheel support so that its position can be set according to the depth of the trench, and it comprises fixed (14) and moving (15) components which are adjustable relative to one another by an actuating cylinder (18).

Description

The present invention relates to a device for digging trenches or the like in the ground, and subsequently allowing the laying of elongated objects such as cables, conduits, pipes, etc.

It is known that such a digging device is generally associated with the chassis of a motorized & wheeled or tracked vehicle and it usually comprises a cutting wheel provided with cutting members which are mounted projecting from the rim or hoop thereof for digging the trench, and a stirrup-shaped wheel support, which is articulated by its base to an orientable and sliding bracket linked to the chassis of said machine, and between the side walls of which is carried the wheel. A rotating mechanism ensures the connection between the wheel and the side walls of the support. And means for driving the wheel in rotation, around the rotating mechanism, are fixed to the support and allow the wheel to make a working face, from bottom to top, of the trench. For example, the working face of trench can correspond substantially to a quarter of the circumference of the wheel, in the case where the trench depth to be produced is maximum (equal to the wheel radius), the axis of rotation of the rotating mechanism of the wheel then being located at the level of the soil to dig.

Although these digging devices prove to be particularly effective for making trenches, they nevertheless have drawbacks with regard in particular to the removal of the cuttings during the digging of the trench.

Indeed, if most of the cuttings produced at each rotation of the wheel are evacuated, at the outlet of the cutting face, respectively on either side of the trench, on the ground, a part of the cuttings tends to s' gradually accumulate between the rim and the tip of the cutting members, as well as in the internal space between the wheel and the stirrup-shaped support of the wheel, especially when these cuttings are sticky or wet. In the more or less long term, this results in a lower efficiency of the cutting members and obliges, thereafter, to stop the device in order to clean the cutting wheel and remove the cuttings accumulated on the rim, the cutting members and in said internal space. The machine is then immobilized for the time necessary to repair the wheel, which penalizes the costs of making the trenches.

The present invention aims to overcome these drawbacks.

For this purpose, the device for digging trenches in the ground, of the type comprising - a cutting wheel with projecting cutting members
on the rim thereof - a stirrup-shaped wheel support, between the walls
side of which said wheel is carried by means of
diary of a rotating mechanism; and - means for driving the rotation of the linked wheel
said support and allowing the wheel to realize a front
in size, from the bottom to the top of said trench, is remarkable, according to the invention, in that it further comprises equipment for removing the excavated material produced during the digging of the trench, said equipment being linked to said support wheel and coming close to the ground at the outlet of the trench cutting face, produced by said wheel, to act on said rim and evacuate the cuttings out of said wheel.

Thus, thanks to the invention, the equipment prevents the accumulation of even clay or wet cuttings, on the rim and the cutting members and in the internal space between the support and the wheel, which allows the device to be able to work efficiently and continuously, reducing the costs of trenching.

Generally, said cutting members are mounted on elements in the form of an angular sector, attached perpendicularly to the peripheral surface of the rim of the wheel. Advantageously, said evacuation equipment then comprises at least one set of two scrapers arranged so as to come close to the peripheral surface of the rim and respectively on both sides of the sectorized elements, to remove said cuttings and evacuate them out of said wheel. , at the outlet of said face.

For example, said scrapers are inclined relative to the peripheral surface of the rim, and are located symmetrically relative to the median plane of the wheel. Consequently, the free lateral edges of each scraper of the equipment are flush with the peripheral surface of the rim and the corresponding side of the segmented elements, by removing and guiding said cuttings towards the outside, out of said wheel.

Preferably, said evacuation equipment is adjustable relative to said wheel support, so as to adapt its working position, close to the ground, as a function of the trench depth to be produced. In this case, said equipment comprises a fixed part, integral with said wheel support, and a movable part adjustable relative to said fixed part by means of actuation means, and carrying said scrapers. For example, said movable and fixed parts are arranged one inside the other and have arcuate configurations and hollow cross sections, inside which the rim and the cutting members of said wheel pass freely.

Said scrapers can be shaped into plates and fixed inside said movable part to act respectively on either side of said cutting members and of said peripheral surface of the rim. One thus notices the simplicity of realization of the scrapers.

Furthermore, an opening is provided in said movable part to allow the evacuation of the cuttings removed and directed by said scrapers, towards the outside through said opening.

According to another characteristic of said evacuation equipment, it may further comprise a support pad capable of being applied to the ground and having a cutout for the free passage of the slicer wheel, at the outlet of the cutting face, during its rotation. Said support pad is then mounted on said movable part, around an axis of articulation perpendicular to the plane of the wheel and parallel to its axis of rotation.

In addition, said equipment further comprises means for transferring said evacuated cuttings. In particular, said transfer means consist of an endless belt conveyor, which is connected to said support shoe, transverse to the plane of the wheel, and on which said excavated cuttings are received, emerging from the opening of the movable part .

The figures of the appended drawing will make it clear how the invention can be implemented. In these figures, identical references designate similar elements.

FIG. 1 represents a motorized vehicle carrying a device for digging trenches according to the invention.

FIG. 2 illustrates an enlarged plan view, partially in section, of the digging device shown in FIG. 1 and provided with said excavation removal equipment.

Figure 3 is a partial cross section of said device, showing the action of the scrapers of said equipment on the cutting wheel of the device.

Figure 4 shows a view of said equipment according to the arrow
F in Figure 2.

FIG. 5 is a cross section of said equipment along the line V-V of FIG. 2.

FIG. 6 is a cross section of said equipment along the line VI-VI of FIG. 2.

As shown in FIG. 1, the motorized vehicle 1 of the track type in this case, carries a device 2 for digging trenches T in the ground S, with a view to subsequently laying cables, pipes or the like. elongated objects not shown.

This digging device 2 mainly comprises a slicer wheel 3, a support 4 for the wheel 3, a rotating mechanism 5 between the support and the wheel, and means for driving in rotation 6 the wheel 3 about the axis
XX of the mechanism, corresponding to that of the cutting wheel 3. In particular, the support 4 of the device consists of parts assembled together, in particular by welding, and it is in the form of an inverted U-shaped bracket, comprising a base 4A and two parallel and spaced side walls 4B, 4C. These extend perpendicularly said base 4A, and the cutting wheel 3 engages between the walls by means of the rotating mechanism 5 which connects the wheel to said walls.

In known manner, the base 4A can be articulated around an axis 7, parallel to the axis XX, on a bracket 8 which is linked to the chassis 1A of the motorized vehicle, so as to be slidable and orientable relative to this one. Maneuvering cylinders 9 connect the base 4A of the support to the bracket 8 to ensure the raising or lowering of the device 2 in the plane of the wheel.

In addition, cutting members 10, each consisting of a peak 10A and a peak holder lOB, are provided projecting around the wheel 3 for digging the trench during the rotation of the wheel and the advance of the motorized vehicle. In this example shown in particular in FIGS. 2 and 3, the cutting members 10 are mounted, preferably by welding, on elements 11 in the form of an angular sector, attached to the peripheral surface 3B of the rim 3A of the wheel. In particular, the sectorized elements 11 are engaged in a groove 3C formed in the median longitudinal plane of the wheel and delimited by two 3D crowns fixed to the peripheral surface 3B of the rim 3A. The segmented elements, for example eight in number, are secured to said crowns by removable fixing means not shown, but known per se.

The rotational drive means 6 of the wheel are defined by geared motors 6A disposed respectively on the walls 4B and 4C of the support and cooperating with the wheel 3, by gears, to drive it in rotation, which allows the organs cutting 10 of the wheel to make a size FT front from bottom to top of the trench T, from its bottom F to the ground level NS. In FIG. 1, the depth of the trench produced by the wheel is maximum and is substantially equal to the radius of the wheel, so that the size front FT corresponds to a quarter of the circumference of the wheel.

Advantageously, the digging device 2 comprises an equipment 12 for evacuating the cuttings D produced during the digging of the trench T. This equipment 12, shown more particularly in FIG. 2, is linked to the support 4 in the form of a stirrup to come near the ground level NS, at the outlet from the cutting face FT produced by the cutting members 10 of the wheel, to act around the rim 3A and evacuate the cuttings out of the wheel, towards the outside.

As shown in FIGS. 2 and 3, the equipment 12 mainly consists, in this embodiment, of a fixed part 14 integral with the support 4, of a movable part 15 relative to the fixed part 14, of at least one set of two scrapers 16 linked to the movable part and coming close to the rim 3A and the segmented elements 11 with cutting members 10, and a support or support pad 17 able to rest on the ground and linked to the mobile part.

Structurally, the fixed and movable parts are nested one inside the other and have arcuate configurations (Figure 2) and square, hollow cross sections (Figure 6), so that inside these can freely pass the rim 3A and the cutting members 10 of said wheel. Obviously, the cross sections of said parts could be different. It can be seen in particular in FIG. 6 that the fixed part 14 is integral with the walls 4B and 4C of the support 4, by means of lugs 14A coming from the fixed part and not shown screwing members. The arcuate movable part 15 is made angularly movable relative to the fixed part 14 and around the axis of rotation XX of the wheel, thanks to actuation means 18, such as two jacks provided respectively on either side of said equipment and articulated for this to the fixed part 14 and to the mobile part 15. Their role will be described later.

To remove the cuttings D which tend to accumulate in the peripheral zone ZP of the rim, that is to say between the peripheral surface 3B of the rim, the 3D crowns and the sectored elements 11 carrying the cutting members 10, the equipment 12 is provided in this example with a set of two scrapers 16.

As shown in Figures 2 to 5, these scrapers are associated with the lower end 15A of the movable part 15 by partially projecting therefrom, and they are located symmetrically on each side of the rim 3A. Structurally, these scrapers 16 are shaped into plates and are fixed, for example by welding, inside the hollow movable part 15. In particular, the scrapers 16 are secured, by one, 16A, to their edges, the internal face 15B of the two opposite sides 15C of the hollow movable part, situated laterally with respect to the rim 3A of the wheel. It can be seen in FIG. 2 that the scrapers 16 are arranged in the same incline plane relative to the peripheral surface 3A of the wheel, roughly tangentially to this surface, so that the cuttings D are directed towards the outside of For this, the free edges, in this case 16B, 16C and 16D, of each scraper respectively come close to the corresponding peripheral surface 3B of the rim, the crown concerned 3D and the cutting members 10 most elements, like the one illustrated in figure 3.

The peripheral zone ZP external to the rim 3A and located on each side of the elements 11, is thus "swept" by the inclined scrapers 16, which ensures constant cleaning of the wheel. In order to guarantee optimal treatment of this area, the profile of the free edge 16D of each scraper could be optimized to take the one illustrated in phantom in Figure 3. Similarly, as Figure 5 suggests with a double arrow, each scraper could be adjustable in sliding and consist of two plates, one of which can slide on another fixed to come to best adapt near the surface of the rim and the outermost cutting members depending on the type used slicer wheel.

Furthermore, an opening 15D is formed in the external curved side 15E of the movable part, opposite the internal side 15F close to the rim, and it thus allows the evacuation of the cuttings D removed and directed by the scrapers 16, towards the outside of the mobile part 15.

As regards the support pad 17 which makes it possible to apply the equipment properly on the ground S, at the outlet of the face of size FT, it consists of a base plate 17A coming into contact with the ground level NS , which is provided with a cutout 17B to allow free passage of the rim 3A of the wheel, and of two legs 17C spaced apart in parallel, which come perpendicularly from the plate 17A and which are articulated in two bearing surfaces 15G formed on the lateral sides 15C of the movable part 15, as shown in FIG. 5. Thus, the shoe can freely pivot around the axis YY defined by the bearings 15G and parallel to the axis of rotation XX of the wheel. This arrangement allows the shoe 17 to adapt as best as possible to the profile of the ground encountered and thus to guide the equipment 12, during the advance of the vehicle 1.

In addition, there is advantageously provided on the plate 17A of the pad, at the front thereof, an endless belt conveyor 19 which is arranged to receive the cuttings D leaving the opening 15D of the movable part 15. It can be seen in FIGS. 1 and 2, that the conveyor 19 is arranged transversely to the direction of advance of the machine 1, so that the cuttings are evacuated towards one of the sides of the trench produced, or towards a receptacle or another belt conveyor, not shown.

We also note, in Figures 1 and 2, that the control cylinder shown 18 is in the retracted position, so that the movable part 15 is in the high position, retracted into the fixed part 14 and the support 4 of the wheel .

Consequently, the plate 17A of the pad is located substantially at the level of the axis of rotation X-X of the wheel 3, which allows the creation of a trench T having a maximum depth, equal to the radius of the wheel. According to the requirements, the position of the movable part 15 of the equipment can thus easily be adjusted relative to the fixed part 14 by controlling the jacks 18, as a function of the trench depth to be produced.

The operation of the digging device 2, provided with the equipment 12 according to the invention, does not raise any difficulty and takes place in the following manner.

When the wheel 3 rotates in the direction indicated around its axis XX, driven by the geared motors 6A, and as a result of the advance of the motorized vehicle 1, the cuttings
D from the ground, torn off by the action of the cutting face FT of the cutting members 10, are brought from the bottom to the top of the trench. They cross the cutout 17B of the plate 17A and 'engage in the movable part 15. Simultaneously, the scrapers 16 located near the ground level NS, remove the cuttings sticking together on the peripheral surface 3B of the rim, on the crowns 3D and on the outermost cutting members 10, and channel them towards the interior of the movable part, to direct them, thanks to their appropriate inclination, towards the opening 15D. The cuttings D exit through the opening to be received on the belt conveyor 19 which discharges them to the outside. It is therefore understood that the wheel 3 is constantly cleaned by the scrapers 16, so that its efficiency is maximum at each rotation thereof and that its operating time is then increased.

We also note that the evacuation equipment 12 forms, thanks to its fixed 14 and mobile 15 parts, a fairing which envelops the front part of the slicer wheel 3 from its support 4 to ground level, which constitutes an important guarantee of security vis-à-vis users.

Claims (13)

1. Device for digging trenches in the ground, of the type comprising - a cutting wheel (3) with cutting members (10) mounted in  projection on the rim (3A) thereof; - a stirrup-shaped wheel support (4) between the walls  side of which said wheel is carried by the intermediary  diary of a rotating mechanism (5); and - rotation drive means (6) of the linked wheel  said support and allowing the wheel to realize a front  in size, from bottom to top of said trench, characterized in that it further comprises equipment for removing (12) the excavated material produced during the digging of the trench, said equipment (12) being linked to said support ( 4) wheel and coming close to the ground at the outlet of the trench cutting face, produced by said wheel, to act on said rim and evacuate the cuttings out of said wheel. 2. Device according to claim 1, of the type in which said cutting members (10) are mounted on elements in the form of an angular sector (11), attached perpendicularly to the peripheral surface (3B) of said wheel rim, characterized in that said discharge equipment (12) comprises at least one set of two scrapers (16) arranged so as to come close to the peripheral surface (3A) of the rim and respectively on both sides of the sectorized elements (11), to remove said cuttings and evacuate them out of said wheel, at the outlet of said cutting face. 3. Device according to claim 2, characterized in that said scrapers (16) are inclined relative to the peripheral surface of the rim, and are located symmetrically relative to the median plane of the wheel (3). 4. Device according to one of the preceding claims 1 to 3, characterized in that said evacuation equipment (12) is adjustable relative to said wheel support, so as to adapt its working position, close to the ground, in depending on the trench depth to be made. 5. Device according to one of the preceding claims 1 to 4, characterized in that said equipment (12) comprises a fixed part (14), integral with said wheel support (4), and a movable part (15) adjustable relative to to said fixed part by means of actuation means (18), and carrying said scrapers (16). 6. Device according to claim 5, characterized in that said movable and fixed parts (14, 15) are arranged one inside the other and have arcuate configurations and hollow cross sections, inside which pass freely the rim and the cutting members of said wheel. 7. Device according to claim 5 or 6, characterized in that said scrapers (16) are shaped into plates and are fixed inside said movable part to act respectively on either side of said cutting members and said peripheral surface of the rim. 8. Device according to one of claims 5 to 7, characterized in that an opening (15D) is provided in said movable part (15) to allow the evacuation of the cuttings removed and directed by said scrapers, towards the outside through said opening. 9. Device according to any one of the preceding claims 1 to 8, characterized in that said discharge equipment (12) further comprises a support pad (17) capable of being applied to the ground and having a cutout (17A) for the free passage of the cutting wheel, at the outlet of the cutting face, during its rotation. 10. Device according to claim 9, characterized in that said support pad (17) is mounted on said movable part (15), about an articulation axis (YY) perpendicular to the plane of the wheel and parallel to its axis of rotation (Xx). 11. Device according to any one of the preceding claims 1 to 10, characterized in that said equipment (12) further comprises transfer means (19) of said excavated cuttings. 12. Device according to claim 11, characterized in that said transfer means (19) consist of an endless belt conveyor which is connected to said support pad (17), transverse to the plane of the wheel, and on which are received said cuttings evacuated, leaving the opening (15D) of the movable part. 13. Device according to any one of the preceding claims 1 to 12, characterized in that said discharge equipment (12) constitutes a protective fairing which envelops the front part of said cutting wheel (3), from its support (4 ) to ground level.