FR2789846A1 - Tool lifting frame for agricultural implement has pivoted arms to support tool with locks to hold in extended and retracted positions - Google Patents

Abstract

The implement has a frame (2) mounted on the implement chassis (1) and carrying two pivoted arm sections (14) and two sections (15) pivoted to these. Locks (29) retain the arm sections in their working positions and further locks (31-33) lock the front sections (15) in their folded positions.

Description

LIFTING DEVICE FOR FRONT MOUNTING

  OR AT THE BACK OF A PARTICULARLY AGRICULTURAL MACHINE

FOR HITCHING A TOOL

  The invention relates to a lifting device intended to be mounted at the front or at the rear of a particularly agricultural machine for the coupling of a tool, comprising: - a frame provided with fixing means on the chassis of the machine, - two arms articulated on the frame around a substantially horizontal axis, and provided with a free end in the form of a hook for coupling a tool, - means for pivoting each arm, suitable to allow to tilt said arms in synchronism between two working positions, called lowered and raised, in each of which the arms extend to the front of the frame with a predetermined inclination relative to a horizontal plane, Such lifting devices are in common use at present in the agricultural field, and are intended to allow to attach an agricultural implement to the front of a tractor or to the rear of a self-propelled loader, and / or transport two agricultural implements simultaneously. In addition, it is common in polyculture and animal husbandry regions for farmers to simultaneously equip their agricultural machinery with a lifting device and a loader for handling manure and / or

hay bales.

  However, in this case there, because of their transverse bulk, the current lifting devices interfere with the stretchers of the loader, during the maneuvers of the latter, so that said loader sees its

  reduced range and therefore cannot be used optimally.

  To overcome this drawback, a first solution consisted in making lifting devices whose arms are removable and can therefore be removed for the use of the loader, so that the latter retains its maximum range. However, this solution requires, in

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  first, repetitive disassembly and reassembly of the arms with all the constraints inherent in these handling operations and the risks linked to these. In addition, once disassembled, the arms must be stored in a place where they can be quickly recovered for possible reuse of the lifting device. To overcome this second drawback, a second solution consisted in providing the frame and the arms with lifting devices with locking means making it possible to secure said arms to said frame, once these have been dismantled, in a position where they do not interfere with 1o stretchers from the loader. However, this solution leaves the drawback associated with

  the obligation to remove the arms in order to use the charger.

  The present invention aims to overcome this drawback and aims to provide a lifting device whose arms can be retracted, without prior disassembly, in a position where their transverse dimensions allow the maneuvers of a loader while keeping the latter its

maximum range.

  To this end, the lifting device according to the invention is characterized in that: - each arm comprises: 20. a longitudinal section, called rear, articulated on the frame around a horizontal axis (x) and on which are coupled the pivoting means, a longitudinal section, called the front section, articulated on the rear section around an axis (x ') inclined relative to the axis (x) so that said front section can pivot between a working position o it extends in the extension of the rear section and o the hooks of the two sections extend parallel to one another, and a folded storage position o said front section is folded in the direction of the frame relative to the rear section, and o the two front sections are inclined transversely one towards the other, - locking means are adapted to lock the front and rear sections of each arm in their working position,

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  - locking means are adapted to lock

  the front sections of the arms in their folded position.

  According to the invention, each arm therefore comprises two longitudinal sections, on the one hand, lockable in a working position in which they form an arm in one piece of conventional design, and on the other hand, whose front section can pivot around an inclined axis, after unlocking, so as to come into a folded position against the frame in which the distance between the axes between said front sections is reduced and allows the loader to be maneuvered without

  interfere with the stretcher of the latter.

  In this way, such a lifting device simply requires, for the use of a loader, to unlock the sections of each arm, and to fold the front section towards the frame. It therefore does not require any disassembly operation and makes it possible to overcome very

  simple the disadvantages of current lifting devices.

  Furthermore, the axis (x ') can have a plurality of orientations, the only requirement consisting in obtaining a relative approximation of the front sections of the arms during their retraction to their folded position. However, according to an advantageous embodiment, the axis (x ') of articulation of the front section of each arm on the rear section of said arm is arranged so as to extend in a vertical plane and to be inclined upwards by an angle (a), when the articulation axis (x) of the rear sections on the frame and the connecting axis (x ") of the articulation axes of the front sections extend in

the same horizontal plane.

  This embodiment constitutes, in fact, the easiest solution to implement from the mechanical point of view and therefore

  leads to an optimized cost price.

  In addition, the angle (a) is advantageously between 10

and 25 degrees.

  According to another characteristic of the invention, the front section has longitudinally, seen from above, the general shape of an S composed of a rear portion on which is mounted the articulation axis, arranged

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  to extend parallel to the rear section in the working position of the arm, a coupling hook parallel to the rear portion, and an intermediate connecting portion inclined at an angle (ct) relative to the longitudinal axis of the portion

back and hook.

  In addition, the front section of each arm advantageously comprises a portion overlapping the rear section of said arm, in the working position of the latter, provided with a notch capable of accommodating a

  removable pin for locking said front and rear sections.

  Furthermore, the means for locking the front section of each arm, in the folded position of the latter, are preferably adapted to allow said front section to be secured to the frame. Thus, the pivoting means, conventionally consisting of hydraulic cylinders, play no role in order to maintain the arms in their folded position, so that the hydraulic circuit supplying these cylinders can be switched and

used for other purposes.

  In the conventional case where the frame comprises two flanges arranged so as to extend on either side of the chassis of the machine, these locking means also advantageously consist of a lock system comprising a solid strike the front section, arranged to accommodate a bolt slidably mounted on the frame, and means for blocking said bolt inside

said strike.

  These locking means can also advantageously comprise, and possibly in addition to those mentioned above, a stop projecting radially from the ankle, adapted to lock against the front section by rotation of said ankle around its

longitudinal axis.

  According to another characteristic of the invention, the rear section of each arm has, longitudinally, seen from the side, the general shape of an L provided with a rear wing articulated on the frame and a front wing on which the articulated front section, the pivoting means being coupled to the wing

  rear slightly upstream of the bend of said rear section.

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  Such an arrangement in fact makes it possible to optimize the positioning of the jack in terms of size at the front or at the rear of the machine. Other characteristics, aims and advantages of the invention

  will emerge from the detailed description which follows with reference to the accompanying drawings

  which represent, by way of nonlimiting example, a preferred embodiment. In these drawings: - Figure 1 is a perspective view of a lifting device according to the invention mounted in front of an agricultural tractor shown in partial and schematic form, said device being in one of its positions of work, - Figure 2 is a perspective view of this lifting device in the folded position thereof, - Figure 3 is a partial view with parts broken away of this lifting device in its folded position, Figure 4 is a front view of this lifting device in its folded position, - Figure 5 is a longitudinal section through a horizontal plane A of this lifting device in one of its working positions, - and Figures 6, 7 and 8 are side views of this lifting device respectively in its lowered working positions and

  raised and in its folded position.

  The lifting device according to the invention is intended to be mounted at the front of an agricultural tractor 1, as shown in Figures 1 and 2, or at the rear of a self-propelled loader, in view of the coupling of agricultural equipment. This lifting device is further adapted to be able to be disposed

  either in useful working positions or in a retracted position of non-

  use allowing in particular the operations of a loader equipping the agricultural machine. This lifting device comprises, firstly, a frame 2 for securing said device to the chassis of the tractor 1, provided with any means

  known per se for fixing said frame to said chassis.

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  This frame 2 comprises two flanges 3, 4 of generally inverted triangular shape, adapted to come and frame the chassis of the tractor 1, and on each of which is fixed a plate such as 5 orthogonal to said flange

  front stop against said chassis.

  The two flanges 3, 4 are further connected, in the upper part, by a shaft 6 arranged so as to extend horizontally at the front of the tractor, on which are joined, in the first place, two middle ears 7, 8 of mounting of a third coupling point, and secondly, two ears 9, 10 each arranged at a short distance from one of said flanges, for mounting of a

o0 cylinder described below.

  These two flanges 3, 4 are also connected, in the lower part, by a horizontal shaft 11 articulated with respect to said flanges so as to

  be able to pivot around its longitudinal axis.

  The lifting device also comprises two arms 12, 13 constituting the first and second coupling points, and secured to

  the shaft 11 so as to be able to pivot relative to the frame.

  Each of these arms 12, 13 is furthermore split longitudinally into two sections such as 14, 15: a rear section 14

  secured to the shaft 11, and a front section 15 articulated on the rear section 14.

  Firstly, each rear section 14 is composed of two bent longitudinal plates 16, 17 extending in parallel and

  secured at their rear end to the horizontal shaft 11.

  These two plates 16, 17 have longitudinally, seen from the side, the general shape of an L, the two wings of which delimit an angle of the order of 150 degrees, which can however vary within a range equal to 180 30, and consist of: an external plate 16, the front end of which is provided with an orifice inside which the end of a horizontal shaft 18 for connecting the rear sections 14 is joined, an internal plate 17 whose front end is

  secured to the peripheral wall of the connecting shaft 18.

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  In addition, these two plates 16, 17 are connected, slightly behind their elbow, by a hollow sleeve 19 extending laterally outward, relative to the external plate 16, through an orifice provided in

the latter.

  Each of these rear sections 14 is connected to the frame 2 by means of a jack 20, 21 whose end of the body such as 20a, is mounted between an ear 9 and the flange 3 associated by means of a cylindrical sheath 22,

  and the end of the rod such as 20b mounted on the sleeve 19.

  Each of these rear sections 14 comprises, finally, in l0 the extension of the connecting shaft 18, an axis such as 23 extending in a plane orthogonal to the plane defined by the axes (x '), (x " ) shafts 11 and 18, and inclined at an angle of the order of 16 to 18 degrees relative to the axis (x ") of said shaft

link.

  The front section 15 of each arm 12, 13, for its part, longitudinally and seen from above, has the general shape of an S composed of: a rear portion 24 provided with a sleeve 25 capable of accommodating the inclined axis 23 , for securing by any means known per se the rear sections 14 and front 15 while allowing the pivoting of said front sections around said inclined axis, - a front portion in the form of a coupling hook 26 extending parallel to the rear portion 24, - and an intermediate portion 27 for connecting the rear portion 24 and the yoke 26, inclined at an angle of the order of 16 to 18 degrees by

  relative to the longitudinal axis of the latter.

  In addition, the rear portion 24 of each of these front sections 15 has a rectangular notch 28 formed at its rear end, adapted to allow the said front sections to be locked in rotation with the rear sections 14 by means of a dowel. 29 of a shape suitable for being housed in said notch and in the sleeve 19 when the latter are opposite one another, corresponding to positions of

arm work 12, 13.

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  To this end, each dowel 29 has a cylindrical axis 29a of diameter conjugate with that of the sleeve 19, and a head 29b of rectangular parallelepiped shape with a section adapted to be housed in the notch 28. In addition, the section of this head 29b is adapted to allow, depending on the orientation of the pin 29 during its installation: - either, as shown in FIG. 6, to lock without play, in a so-called fixed position, the front 15 and rear 14 sections of each arm

12, 13,

  - Or, as shown in Figure 7, to lock said front and rear sections in a so-called floating position, allowing

  travel of the front sections 15 for adapting the tools to the ground.

  Each ankle 29 furthermore has a radial shim, disposed at the level of the head 29b of the latter and whose function is

explained below.

  Each front section 15 comprises, finally, a ring 31 housed in a notch formed in the upper edge of the intermediate portion 27, and adapted to act as a keeper capable of housing a cylindrical bolt 32 mounted to slide in the sheath 22, and to form with said bolt a locking bolt for said front sections in a folded position

explained below.

  As shown in particular in Figures 1, 2 and 6, 7, 8, such a lifting device is designed to allow each arm 12, 13 to be placed in two different positions: - a working position shown in Figures 1, 6 and 7 , in which the front 15 and rear 14 sections are locked by means of the pins 29, either in a fixed position (FIG. 6) or in a floating position (FIG. 7), the front sections 15 extending in the extension of the sections rear 14, and the coupling hooks 26 being arranged parallel to each other. In this working position, and conventionally, each arm 12, 13 can be made to pivot about the axis of the shaft 11, between a lowered position (FIG. 6) and a raised position (FIG. 7) under the action of the cylinders 20, 21,

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  - A folded position shown in Figures 2 and 8 obtained, after removal of the pins 29, by pivoting the front sections 15 relative to the rear sections 14, around the inclined axis 23, and in which the coupling hooks 26 are brought transversely , automatically, near the flanges 3, 4. In this position, moreover, the bolts 32 are brought by sliding in the keepers 31, and are locked by the installation of a pin 33. To this end, as shown in FIG. 3, each bolt 32 is pierced with two transverse radial bores 32a, 32b spaced apart longitudinally, making it possible to block it in translation, on the one hand in the above-mentioned active locking position of the arms 12, 13 folded back, and on the other hand, in a passive position where it authorizes the pivoting of the front sections 15. In addition, for safety, the radial wedge 30 of the pins 29 is brought into abutment

  against the rear portion 24 of each arm 12, 13.

  By way of example, a lifting device according to the invention having a conventional transverse size of 920 mm in the working position, sees this transverse size reduced to a value between 600 and 700 mm in its folded position. In this way, such a reduced transverse size allows the use of a loader while keeping at

the latter its maximum range.

  In addition, it should be noted that in the folded position of the arms 12, 13, the latter are locked to the frame 2 so that the jacks 20, 21 do not participate in any way in maintaining this folded position. The hydraulic supply circuit of these jacks 20, 21 can therefore be switched and used

for other purposes.

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Claims (6)

  1 / -Lifting device intended to be mounted at the front or at the rear of a machine in particular agricultural, for the coupling of a tool, comprising: - a frame (2) provided with fixing means on the chassis (1) of the machine, - two arms (12, 13) articulated on the frame (2) around a substantially horizontal axis, and provided with a free end in the form of a hook (26) of coupling of a tool, - means (20, 21) for pivoting each arm (12, 13), capable of making it possible to tilt said arms in synchronism between two working positions, called lowered and raised, in each of which the arms (12, 13) extend in front of the frame (2) with a predetermined inclination with respect to a horizontal plane, said lifting device being characterized in that: - each arm (12, 13) comprises: a longitudinal section (14), called rear, articulated on the frame (2) about a horizontal axis (x) and on which the pivoting means (20, 21), 20 are coupled. u n longitudinal section (15), called front, articulated on the rear section (14) about an axis (x ') inclined relative to the axis (x) so that said front section can pivot between a working position o it extends in the extension of the rear section (14) and o the hooks (26) of the two front sections (15) extend parallel to each other, and a folded storage position o said front section is folded in the direction of the frame (2) relative to the rear section (14), and o the two front sections (15) are inclined transversely one towards the other, - locking means (29) are adapted to lock the front (15) and rear (14) sections of each arm (12, 13) in their working position, - locking means (31-33) are suitable for   lock the front sections (15) of the arms (12, 13) in their folded position.   il 2789846 2 / - Lifting device according to claim 1, characterized in that the axis (x ') of articulation of the front section (15) of each arm (12, 13) on the rear section (14) of said arm is arranged so as to extend in a vertical plane and to be inclined upwards by an angle (a), when the articulation axis (x) of the rear sections (14) on the frame (2) and the axis (x ") connecting the articulation axes of the front sections (15) extend in the same horizontal plane. 3 / Lifting device according to claim 2,   characterized in that the angle a is substantially between 10 and 25 degrees.   4 / - Lifting device according to one of claims 2   or 3, characterized in that the front section (15) presents longitudinally, seen from above, the general shape of an S composed of a rear portion (24) on which the articulation axis is mounted, arranged for s 'extend parallel to the rear section (14), in the working position of the arm (12, 13), a coupling hook (26) parallel to the rear portion (24), and an intermediate portion (27 ) of connection inclined with respect to the longitudinal axis of the rear portion (24) and the hook (26).   / - Lifting device according to one of claims   previous, in which the front section (15) of each arm (12, 13) comprises a portion overlapping the rear section (14) of said arm, in the working position of the latter, provided with a notch (28) suitable to house an ankle   removable (29) for locking said front and rear sections.   6 / - Lifting device according to one of claims   above, characterized in that the locking means (31-33) of the front section (15) of each arm (12, 13), in its folded position, are adapted to   allow to secure said front section to the frame (2).   7 / - Lifting device according to claim 6 wherein the frame (2) comprises two flanges (3, 4) formed so as to extend on either side of the chassis (1) of the machine, characterized in that the means for locking the front section (15) of each arm (12, 13) on said frame consist of a lock system comprising a keeper (31) integral with said 12 2789846   front section, arranged to accommodate a bolt (32) sliding on the frame, and   means (33) for locking said bolt inside said keeper.   8 / - lifting device according to claim 5, characterized in that the means for locking the front section (15) of each arm (12, 13) comprise a stop (30) projecting radially relative to the pin (29) , adapted to lock against said front section by rotation of   said pin around its longitudinal axis.   9 / - Lifting device according to one of claims   previous, in which the rear section (14) of each arm (12, 13) has 1o longitudinally, seen from the side, the general shape of an L with a rear wing articulated on the frame (2) and a front wing on which the front section (15) is articulated, the pivoting means (20, 21) being hitched to the rear wing slightly   upstream of the bend of said rear section.