Working machine and assembly comprising such a machine

The invention concerns a working machine (1) comprising a mobile chassis (2) that can move on a surface of the ground, a lifting arm (3) mounted on the chassis (2) to pivot about a horizontal axis (4) for a raising and lowering movement of the arm (3), and an accessory coupler (5) that can be secured to the free end of the arm (3) by a pivot link (6) with axis parallel to the axis (4) for pivoting the arm (3) with respect to the chassis (2). The coupler (5) comprises a plate (7) having a rear face (8) facing the arm (3) equipped with said pivot link (6) of the coupler (5) to the arm (3) and an opposite front face (9). The plate (7) is provided with a through-opening (10) and at least one part (61) of the pivot link (6) connecting the coupler (5) to the arm (3) is arranged facing said opening (10).

The present invention relates to a working machine and to an assembly comprising such a working machine and an accessory that can be coupled to the coupler of said machine.

It relates in particular to a working machine comprising a wheeled or tracked frame which can be displaced on the ground surface, a lifting arm mounted on the frame so as to be able to pivot about a horizontal axis for an upward and downward displacement of the arm, and an accessory coupler which can be secured to the free end of the arm by way of a pivot connection having an axis parallel to the pivoting axis of the arm relative to the frame.

It is conventional to use a coupler forming an interface between an accessory, such as a hopper, or bucket, a blade, a sweeper or the like, and the arm of a working machine to fix the accessory to the arm. It is often necessary to attach an adapter to the coupler to allow certain accessories to be received. A solution is therefore sought that makes it possible to dispense with the presence of an adapter without adversely affecting the versatility of the coupler.

An object of the invention is to provide a working machine having a design which allows the coupler to have great versatility without adversely affecting its simplicity.

To that end, the subject of the invention is a working machine comprising a movable frame which can be displaced on the ground surface, a lifting arm mounted on the frame so as to be able to pivot about an axis, referred to as horizontal axis, for an upward and downward displacement of the arm, and an accessory coupler which can be secured to the free end of the arm by way of a pivot connection having an axis parallel to the pivoting axis of the arm relative to the frame, characterized in that said coupler comprises a plate having a face, referred to as rear face, that faces the arm and is equipped with at least a part of said pivot connection connecting the coupler to the arm and an opposite face, referred to as front face, in that the plate is provided with a through-opening, and in that that part of said pivot connection connecting the coupler to the arm with which the rear face of the plate is equipped is arranged facing said opening. The presence of a through-opening allows an accessory arranged so as to at least partially bear against the front face side of the plate to be able to protrude through said opening toward the arm. Thus, the through-opening makes it possible to manage the possible bulk of the accessory. Furthermore, such a design allows the production of a lightweight coupler and a limited offset of the accessory.

According to one embodiment of the invention, said through-opening, delimited by edges, is an opening referred to as being upwardly open in the upright state of the plate, one of the delimiting edges of said opening, forming the upper edge of said opening in the upright state of the plate, being an open edge. Again, this arrangement makes it possible to have a large clearance at the through-opening.

According to one embodiment of the invention, the plate in the upright state has the overall shape of a U, the space left free between the branches of the U forming said through-opening. The through opening can thus occupy a central position.

According to one embodiment of the invention, the coupler is provided with a reinforcing element extending from the rear face side of the plate. This reinforcing element prevents deformation of the plate without adversely affecting the ways in which the accessory can be coupled to the coupler.

According to one embodiment of the invention, the reinforcing element, which comprises a tubular element, connects the branches of the U to one another, at the free end of the branches of the U. This prevents a risk of separation or deformation of the branches of the U.

According to one embodiment of the invention, the tubular element of the reinforcing element has a circular section. Preferably, the tubular element of the reinforcing element is formed by a profile attached and welded to said plate via two end flanges connecting the profile to the back, or rear face, of the plate. Each end flange bearing by way of its edge against the rear face of the plate is interposed between two gusset plates arranged on either side of the flange and coupling the flange to the rear face of the platform.

According to one embodiment of the invention, the plate is provided, on the rear face side, with two aligned profiles, said profiles extending parallel to the pivot axis of the pivot connection connecting the coupler to the arm, on either side of said through-opening in the coupler. These two profiles allow an interlocking engagement with complementary recessed parts of the accessory.

Preferably, each profile is an L-shaped bracket applied to the rear face of the plate.

According to one embodiment of the invention, the coupler comprises, for the purpose of coupling an accessory to the coupler, on the rear face side of the plate, two locking pins, preferably parallel, extending transversely, preferably orthogonally, to the axis of the pivot connection connecting the coupler to the arm, each of said locking pins being equipped with a handle for driving said locking pin in translation so as to displace said locking pin between an unlocked position and a locked position and with a spring for returning said locking pin to the locked position. The locking pins thus make it possible to lock the interlocking connection between the coupler and the accessory.

According to one embodiment of the invention, the plate of the coupler is delimited by edges and the through-opening in the coupler is an opening extending centrally between two opposite edges of said plate. In other words, the plate and the through-opening are each delimited by edges, two opposite edges of the opening respectively extending equidistantly from two opposite edges of the plate.

According to one embodiment, that part of said pivot connection connecting the coupler to the arm with which the rear face of the plate is equipped and which is arranged facing said opening forms a one-piece assembly with said plate. In this way, that part of the pivot connection connecting the coupler to the arm with which the rear face of the plate is equipped forms with said plate an assembly that is incapable of being dismounted.

According to one embodiment of the invention, that part of said pivot connection connecting the coupler to the arm with which the rear face of the plate is equipped and which is arranged facing said opening is in the form of a sleeve delimiting a through-passage.

According to one embodiment of the invention, the arm is provided with a ram which can be coupled to the coupler, on the rear face side of the plate of the coupler, by way of a pivoting connection having an axis parallel to the axis of the pivot connection connecting the arm to the coupler for the purpose of driving the plate in rotation about the pivot axis of the pivot connection connecting the coupler to the arm in the actuated state of said ram. The plate is therefore a plate that can be oriented using said ram.

Another subject of the invention is an assembly comprising a working machine and an accessory, characterized in that the working machine is in accordance with that described above.

As mentioned above, the working machine1, which is an object of the invention, comprises a movable frame2which can be displaced on the ground surface via wheels as in the example shown or via tracks.

This frame2is surmounted by a lifting arm3that is coupled pivotably to the frame2. This lifting arm3is mounted on the frame2so as to be able to pivot about an axis4, referred to as horizontal axis, for an upward and downward displacement of the arm3.

The working machine1also comprises an accessory coupler5which can be secured to the free end of the arm3by way of a pivot connection6having an axis parallel to the pivoting axis4of the arm3relative to the frame2.

The accessory30with which the coupler5can be coupled may take many forms depending on the work to be carried out by the machine1. Thus, this accessory30may be, for example, a bucket in the case of a load-handling machine, a blade in the case of a snowplow-type machine, a claw, a sweeper or the like without departing from the scope of the invention.

This coupler5comprises a plate7having a face8, referred to as rear face, that faces the arm3and is equipped with a part61of the pivot connection6connecting the coupler5to the arm3and an opposite face9, referred to as front face. Another part of the pivot connection6connecting the coupler5to the arm3is borne by the arm3and a pin allows said parts of the pivot connection6to be held together in the coupled state. The pivot connection6therefore comprises a part61borne by the plate7and a part borne by the arm3.

The accessory30is intended to at least partially bear against the front face9of the plate7in the state in which it is coupled to said plate7. To allow an orientation of the plate7of the coupler5in the state in which the coupler5is secured to the arm3by way of the pivot connection6, the arm3is provided with a ram22which can be coupled to the coupler5on the rear face side8of the plate7of the coupler5by way of a pivoting connection23having an axis parallel to the axis of the pivot connection6connecting the arm to the coupler5. This ram22allows the plate7to be driven in rotation about the axis of the pivot connection6connecting the coupler5to the arm3in the actuated state of the ram22.

This ram22is arranged on the bottom face side of the arm3. Thus, the extension of the ram22by removing the stem of the ram22drives an upwardly pivoting displacement of the plate7, while a retraction of the ram22by inserting the stem of the ram22drives a downwardly pivoting displacement of the plate7, as is illustrated inFIG.4. The plate7is thus able to occupy an upright position in which it extends in a vertical plane.

This plate7which is delimited by edges71may be provided, along one or two of its edges, referred to as horizontal edges, which extend parallel to the pivot axis of the pivot connection6connecting the coupler5to the arm3, with flanges for reinforcing said plate7.

The plate7is provided with a through-opening10and that part61of the pivot connection6that is arranged on the rear face side of the plate7and that makes it possible to connect the coupler5to the arm3is arranged facing said opening10. In the example shown, the plate7has, in the upright state, the overall shape of a U. The space left free between the branches15of the U forms said through-opening10. This through-opening10delimited by edges shown by11,12,13in the figures is an opening referred to as being upwardly open in the upright state of the plate7.

One of the delimiting edges of said opening10forming the upper edge11of said opening in the upright state of the plate7is therefore an open edge. The lower edge12of the opening10is formed by a part of the core16of the U. Thus, the through-opening10in the coupler5is an opening extending centrally between two opposite edges71of said plate7, these opposite edges71of said plate7forming the vertical edges of said plate in the upright state of said plate. That part61of said pivot connection6connecting the coupler5to the arm3with which the rear face8of the plate7is equipped and which is arranged facing said opening10forms a one-piece assembly with said plate7. This part61of said pivot connection6connecting the coupler5to the arm3with which the rear face8of the plate7is equipped and which is arranged facing said opening10is in the form of a sleeve delimiting a through-passage.

That part of the pivot connection6that is borne by the arm3is formed by two through-passages, each of which can be positioned at one end of the sleeve before a pin is inserted in the assembly thus formed.

In the examples shown, that part61of the pivot connection6connecting the coupler5to the arm3that is in the form of a sleeve is kept secured to the plate7by two parallel flanges through which said sleeve passes. These two flanges are fixed to the lower edge12of the through-opening10in the plate7and to a reinforcing element14which will be described below.

This arrangement results in reduced bulk of the opening10and of the pivot connection6connecting the coupler5to the arm3without adversely affecting the option for the accessory30to partially protrude through said opening10when the bulk of the accessory30necessitates such mounting.

To avoid any deformation of the plate7under the effect of the weight of the accessory30and possibly of a load, the coupler5is provided with a reinforcing element14extending from the rear face side8of the plate7. This reinforcing element14, which comprises a tubular element having a circular section, connects the branches of the U to one another at the free end of the branches of the U. This reinforcing element14therefore forms a bridge connecting the branches of the U to one another at the free end of the branches of the U. The tubular element of this reinforcing element14is formed by a profile attached and welded to said plate via two end flanges connecting the profile to the back, or rear face, of the plate7. Each end flange24bearing by way of its edge against the rear face of the plate7is interposed between two gusset plates25arranged on either side of the flange and coupling the flange to the rear face of the plate7. The tubular element of the reinforcing element14therefore extends away from the plate7in the state in which it is fixed to said plate7so as to keep the through-opening10in the plate7as free as possible.

To allow a connection between the coupler5and an accessory30, the plate7is provided, on the rear face side, with two aligned profiles17. These profiles17extend parallel to the pivot axis of the pivot connection6connecting the coupler5to the arm3on either side of said through-opening10in the coupler5. These profiles17may each be formed by an L-shaped bracket applied to the rear face of the plate. The rear face of the plate closes the L of each of the profiles17. The two profiles17are arranged at the free ends of the branches15of the U of the plate7.

The accessory30may have recessed parts intended to cover these profiles17. This results in an interlocking connection between the coupler and the accessory. To lock this interlocking connection, the coupler5comprises, on the rear face side8of the plate7, two locking pins18, preferably parallel in this instance. These locking pins18extend transversely, preferably orthogonally, to the axis of the pivot connection6connecting the coupler5to the arm3. These locking pins18are each equipped with a handle19for driving the locking pin18in translation so as to displace said locking pin18between an unlocked position and a locked position and with a spring20for returning said locking pin18at least to the locked position.

In this way, in practice, the coupler5and an accessory30are mounted at the end of the arm3as follows: the coupler5is placed on the ground and rests with the front face9of the plate7against the ground. The arm3is moved closer to the rear face8of the plate7to make it possible, by means of attached pin ends, to pivotably couple the ram22and the arm3to the plate7. Bushings or circlips may be used to keep a first pin end in aligned housings in the arm and in the coupler and to keep a second pin end in aligned housings in the ram and in the coupler. On each occasion, these aligned housings delimit a pin passage in a manner known per se so as to produce a pivot connection. At this juncture, the pivot connection6between the arm and the coupler has been described in detail above.

Once the coupler5has been fixed to the arm3and to the ram22of the machine1, the accessory30is coupled to the coupler5. Before coupling, the accessory rests on the ground and the handles19for actuating the locking pins18of the coupler5are in the unlocked position of the locking pins18.

The arm and the coupler are driven in displacement as far as a position in which the coupler bears, by way of the front face9of its plate7, against a bearing surface of the accessory30, and the profiles17of the coupler are inserted from below in the recessed parts of the accessory30, the opening of these recessed parts facing the ground.

Once the interlocking has been done, the position is locked by actuating the handles19for operating the locking pins18, the free ends of which can be inserted in the housings in the accessory. Once this mounting is complete, the accessory30can protrude to a greater or lesser extent through the through-opening10in the plate7toward the arm3.

The machine1is ready to work. The coupler and the accessory are dismounted in reverse, firstly with the accessory being dismounted from the coupler then, secondly, the coupler being dismounted from the arm.