FR3112452A1 - Coupling device and coupling method - Google Patents

Abstract

Coupling device and coupling method. Device for coupling an agricultural tool to a tractor, comprising a male frame 2 and a female frame 3 adapted to be joined together, and comprising on their upper parts a hook 21 and an attachment member 31 integral with the frames 2, 3 respective forming means 4 for approaching and positioning the frames 3,4 one against the other. Method for hitching an agricultural tool to a tractor comprising the following steps: - a male frame 2 is mounted on a tractor and a female frame 3 on an agricultural tool, - a hook 21 is positioned in the position projecting forwards of the male frame 2, - the hook 21 is brought closer to a hooking member 31 of the female frame 3, - the hook 21 is made to cooperate with the hooking member 31, - a tractor lifting system is actuated to bring the male frame 2 back to a vertical position, - once the frames are joined together, locking means 4 of one frame against the other are actuated. Figure for abstract: Fig.1

Description

Coupling device and coupling method

The technical field concerns that of equipment for vehicles, in particular agricultural vehicles, such as for example agricultural tractors.

The technical field also concerns that of coupling devices or interfaces used to equip a vehicle with equipment and connect this equipment to said vehicle.

The technical field concerns more particularly that of the coupling devices of an agricultural tool on a three-point lifting system of an agricultural tractor, making it possible to couple not only the tool to the tractor, but also the power take-off.

As quoted in document FR2995756, "a report from the French Ministry of Agriculture in a collective work entitled "tractor-tool links" published in 2006 indicates that the coupling and uncoupling operations of agricultural tools on the three-lift points of agricultural tractors are very delicate operations to carry out and are the cause of many accidents. In fact, the only way favored in this report consists in the installation of "hitching triangles" made up of two frames in the shape of a triangle adapted to be secured respectively to the three-point lifting system of the agricultural tractor and to the implement. agricultural, and intended to be designed to fit together in a single operation by the operator from his driving position. In fact, the use of such coupling triangles is reduced due to the difficulties encountered by operators in order to fit the coupling triangles correctly without leaving their driving position. ".

The document FR2995756 teaches a solution consisting in producing a coupling device comprising two frames adapted to be secured respectively to the three-point lifting system of the agricultural tractor and to the agricultural tool, this solution having the main objective of providing a device for hitch making it easy to achieve, directly from the driving position, the juxtaposition and the relative locking of these two frames. This solution makes it possible to provide a coupling device designed to allow direct coupling, from the driving position, of the cardan drive shafts connected to the agricultural tractor and to the agricultural implement.

This document more particularly teaches a coupling device for an agricultural tool on a three-point lifting system of an agricultural tractor with a longitudinal axis, comprising two frames adapted to extend along transverse axes at least substantially orthogonal to the longitudinal axis, transversely with respect respectively to the agricultural tractor and to the agricultural implement, and consisting of a so-called male frame provided with members for fixing to the three-point lifting system, and a so-called female frame provided with fastening members at the agricultural tool, said male and female frames being adapted to be joined together and comprising relative locking means. This coupling device is characterized in that the male frame and the female frame each comprise two elements, called soles, arranged so, on the one hand, that the soles of each frame are aligned along the transverse axis, and on the other hand, that each sole of the male frame is positioned below a sole of the female frame, so as to form, with the latter, a pair of soles provided with planar contact faces arranged to come opposite the one another in an initial position of pre-positioning of the agricultural tractor relative to the agricultural tool, and to be superimposed in contact with one another in the contiguous final position of the two frames, one of the soles of each pair of soles being pierced with an orifice of predetermined section and dimensions, and the other sole of each pair of soles comprising, projecting from its contact face, a centering member of decreasing section along at least two planes perpendicular to the said face contact and respectively parallel to the longitudinal and transverse axes, from a base section of dimensions conjugate to that of the orifice of the other sole.

The document teaches that such a coupling device thus comprises two frames designed to be juxtaposed in an adjoining position allowing them to be locked, by simply lifting the three-point lifting system of an agricultural tractor, and this without requiring rigorous alignment of the agricultural tractor during its positioning relative to the agricultural tool.

Thus, it is estimated that with such a solution the positioning margin offered to the operator can reach at least 10 to 20 cm both along the longitudinal axis and along the transverse axis, dimensions which easily allow an operator to average ability to correctly pre-position the agricultural tractor.

The solution taught by the document FR2995756 however has drawbacks. First of all, the positioning margin is relatively small, around ten centimeters. Thus, an agricultural tractor must pre-position itself near and opposite the tool to position the male frame correctly in relation to the female frame. This pre-positioning can be made difficult in a hangar for example, which does not always allow you to be able to stand opposite the tool storage location.

In addition, such a coupling device has a large number of elements, which makes the maintenance of such a device more complex.

The objective of the invention is therefore to propose an alternative solution to that taught in document FR2995756 which meets the same objectives while not having the drawbacks mentioned above. Another object of the invention is to provide a coupling device that is simple, robust and economical to manufacture.

Other aims and advantages of the present invention will appear during the description which will follow, referring to the attached drawings illustrating exemplary embodiments and in which:

is a schematic view in rear perspective of two frames spaced apart from each other forming the device according to the invention;

is a schematic front high perspective view of the two frames of the cooperating with each other by their upper part, according to another angle of view;

is a sectional view according to III-III of the frames of the ;

is a schematic sectional view along IV-IV of the frames cooperating with each other via their upper part of the ;

is a schematic view of the buildings of the cooperating with each other by their upper part, in a position prior to the joining of the two frames against each other;

is a schematic view of the buildings of the stuck against each other.

The invention as illustrated in Figures 1 to 6 relates to a coupling device 1 of a tool, in particular agricultural, not shown here, on a three-point lifting system of a tractor, in particular agricultural, not shown here. . This coupling device 1 is configured to form an interface between the agricultural tractor and the agricultural tool.

The coupling of the tractor, the interface and the attached implement has a virtual longitudinal steering axis.

Of course, such a coupling device 1 can be used for non-agricultural uses.

This hitching device 1 comprises two frames 2, 3, a so-called male frame 2 provided with fixing members 20 to the three-point lifting system of the agricultural tractor that it equips, and a so-called female frame 3 provided with fixing 30 to the agricultural tool that it equips.

With reference to the , the frame on the right of the figure is the male frame 2 and the frame on the left of the figure is the female frame 3. The male frame 2 is configured to be connected to a tractor located at the front of the device. coupling 1, i.e. which would be to the right of the , and the female frame 3 is configured to be connected to a tool located at the rear of the coupling device 1, which would be to the left of the .

Thus, the male frame 2 is provided at the front with members 20 for fixing to the three-point lifting system of the tractor, and the female frame 3 is provided at the rear with members 30 for fixing to the agricultural tool.

Referring to Figures 1 and 3 to 6, the coupling device 1 is considered in the following description in the position of use, that is to say that the coupling device 1 is considered to be positioned according to a general vertical orientation. Thus, in Figures 1 and 3 to 6, the coupling device 1 comprises an upper part at the top of the figures, and a lower part at the bottom of the figures.

The male 2 and female 3 frames are here two mechanically welded structures, carried by transverse planes to the longitudinal master plane of the coupling. These frames each have the general shape of a triangle, the base of which is in the lower part of the device and the main apex is in the upper part of the coupling device 1.

The male 2 and female 3 frames are adapted to be joined together as shown in the .

The male frame 2 and the female frame 3 comprise on their upper part, at the level of their main vertex, one a hook 21 and the other an attachment member 31 cooperating with each other to form means of approach and positioning 4 of the frames 2, 3 against each other. The hook 21 is integrally and fixedly mounted on the male frame 2 and oriented upwards, as illustrated in the figures. The attachment member 31 is integrally and fixedly mounted on the female frame 3, as illustrated in the figures.

By acting on the front fasteners 20 of the male frame 2, an operator on the tractor can command a tilt of the male frame 2 to make the hook 21 protrude with respect to the rest of the frame 2, as illustrated in Figures 1 or 3.

This position allows the hook 21 to cooperate with the attachment member 31, although the bases of the frames 2, 3 are distant from each other, and although the frames 2, 3 are not facing one of the other.

The male frame 2 comprises means 5 for guiding the female frame 3 towards a position of abutment of the female frame 3 against the male frame 2, here in the form of a sheet or wing 5 extending perpendicularly from one end of the base of the male frame 2 or the lower part of the male frame 2 backwards. Only one wing 5 is illustrated in the figures, and in particular in Figures 1 and 2, but it is understood that the coupling device 1 can include another wing 5 at the other end of the base of the male frame 2. In the case of two wings 5 on the male frame 2, the base of the female frame 3 has a width less than the spacing between the two said wings 5. The or both wings 5 can also extend from the male frame 2 according to a divergent shape moving away laterally towards the outside of the coupling device 1.

Of course, according to an alternative embodiment, it may be the female frame 3 which may comprise means 5 for guiding the male frame 2 towards a position of abutment of the male frame against the female frame, in particular in a form similar to those previously described.

The attachment member 31 may be formed of a horizontal bar here, the director axis of which is included in the plane which carries the female frame 3, as illustrated in FIGS. 1 or 2. Advantageously, this bar has a width at least one and a half times, preferably twice, the width of the hook 21.

The hooking member 31 can be formed of a curved bar extending towards the rear of the frame 3, which facilitates the approach and the hooking of the hook 21 when the frames 2, 3 are not facing each other, in order to make the hook 21 cooperate with the attachment member 31.

The male frame 2 and the female frame 3 may comprise means for locking relative to each other when the female frame 3 is attached against the male frame 2. These locking means may for example comprise a housing in a wing 5 of the male frame 2, in which a trigger of the female frame 3 engages. This trigger can be controlled by a cylinder of the female frame 3 to move the trigger in a direction perpendicular to the cutting plane IV-IV used to make the . The trigger engaged in the housing then makes it possible to lock the two frames 2, 3 to each other when they are joined.

As illustrated on the and FIGS. 4 and 5, the male frame 2 may include lugs 22 which engage in openings 32 of the female frame 3, or vice versa, to form means for centering the male frame 2 with respect to the female frame 3 when the frames 2, 3 are close to joining together as shown in the .

The male frame 2 comprises a male transmission member 6 adapted, on the one hand, to be coupled to a universal joint transmission shaft fitted to the agricultural tractor, and on the other hand, when the male frame 2 is attached against the female frame 3, to cooperate with a female transmission member 7 of the female frame 3, said female transmission member 7 being adapted to be coupled to a universal joint transmission shaft fitted to the agricultural tool.

The male transmission member 6 comprises a splined male section 60, the male section 60 and the splines extending perpendicularly to the male frame 2 forwards.

The female transmission member 7 has a front part 70 and a rear part 71 that are integral in rotation. The front part 70 can be coupled to a universal joint transmission shaft fitted to the agricultural tool.

The rear part 71 comprises a bore perpendicular to the female frame 3, provided with grooves perpendicular to the female frame 3, the rear part 71 being open on the rear of the female frame 3 and intended for coupling with the male transmission member 6 and more particularly the male splined section 60.

This rear part 71 can translate from front to rear in a chamber 72 of the female transmission member 7, between a disengaged position where the rear part 71 is to be shifted towards the front of the female frame 3 and a position of clutch where the rear part 71 is at the rear of the female frame 3. Spring-type elastic return means exert a return force from the rear part 71 in the chamber 72 towards the engaged position.

The teeth of the splines of the male section 60 of the male transmission member 6 and of the splined bore of the rear part 71 of the female transmission member 7 advantageously consist of engaging teeth so as to facilitate the coupling between the rear part 71 in the engaged position and the male section 60.

In fact, when the male frame 2 comes to rest against the female frame 3, it happens that the splines of the male section 60 are not well positioned with respect to the splines of the rear part 71, preventing their coupling. The rear part 71 is then pushed back by the male section 60 into the disengaged position. Once the two frames 2, 3 joined, it is then sufficient to actuate the rotation of the male transmission member 6 and therefore of the male section 60, for example by actuating the rotation of the universal joint transmission shaft fitted to a tractor equipped with the coupling device 1. The male section 60 then pivots until it reaches a position allowing it to engage in the rear part 71 of the female transmission member 7. The elastic return means then push the rear part 71 on the male section 60, in the engaged position. The two transmission members 6, 7 are then coupled.

The female frame 3 can, in addition, be equipped with a foot 8, as illustrated in the , adapted to be deployed under said female frame 3, so as to support the latter after unhitching the agricultural implement from the tractor. This foot 8 can be actuated for example by a hydraulic cylinder allowing it to pivot from a retracted position, as illustrated in the , in a deployed position, said foot or hydraulic cylinder being controllable from the tractor.

The invention also relates to a method for coupling an agricultural tool to a three-point lifting system of an agricultural tractor comprising the following steps:
- a so-called male frame 2 of a coupling device 1 is mounted, said male frame 2 being provided with fasteners 20 to a three-point lifting system, on the three-point lifting system of a tractor and mounts a so-called female frame 3 of said coupling device 1, said female frame 3 being provided with fasteners 30 to an agricultural tool,
- the male frame 2 is positioned so that a hook 21 on its upper part is in a position projecting forward relative to the male frame 2,
- the hook 21 of the male frame 2 is brought closer to a hooking member 31 on the upper part of the female frame 3,
- the hook 21 of the male frame 2 is made to cooperate with the attachment member 31 of the female frame 3,
- The lifting system is actuated to bring the male frame 2 back to a vertical position; in doing so, the female frame 3, held to the male frame 2 by the hook 21 cooperating with the attachment member 31, pivots and approaches the male frame 2, guide means 5 guiding the female frame 3 towards a position of joining of the female frame 3 against the male frame 2,
- Once the female frame 3 attached to the male frame 2, it actuates locking means of a frame with the other.

According to an additional but optional step of the preceding method, a cardanic transmission shaft fitted to the agricultural tractor is actuated which drives a male transmission member 6 of the male frame 2 to which it is coupled, said male transmission member 6 then cooperating with a member female transmission 7 of the female frame 3, itself being adapted to be coupled to a universal joint transmission shaft fitted to the agricultural tool.

According to an additional but optional step of the preceding method, a foot 8 of the female frame 3 adapted to be deployed under said female frame 3 is folded up so as to support the latter after the agricultural tool has been unhitched from the tractor.

The method described above can be implemented by a coupling device 1 as described previously.

The coupling device 1 as described above allows the implementation of the method described above.

Thus, such a coupling device 1 and such a method make it possible to pick up, with a hook 21 of a male frame 2 attached to a tractor, a hooking member 31 of a female frame 3 attached to a tool, even if the frames 2, 3 are not facing each other.

Thus, an agricultural tractor no longer has to come and preposition itself opposite the tool in order to correctly position the male frame 2 with respect to the female frame 3, simplifying the work of an operator of average skill responsible for correctly prepositioning the tractor. agricultural.

Claims (3)

Device for hitching an agricultural tool on a three-point lifting system of an agricultural tractor, comprising two frames 2, 3 extending along planes transverse to the longitudinal director axis of the hitch, a so-called male frame 2 provided at the front with fasteners 20 to the three-point lifting system and a so-called female frame 3 provided at the rear with fasteners 30 to the agricultural tool, the said male 2 and female 3 frames being adapted to be joined, characterized in that the male frame 2 and the female frame 3 comprise, on their respective upper parts, one a hook 21 and the other a hooking member 31 integral with the respective frames 2, 3 , cooperating with each other to form means 4 for approaching and positioning the frames 2, 3 one against the other, and in that the device comprises guide means guiding the female frame 3 towards an abutting position of the female frame 3 against the male frame 2 and means for locking a frame i 2, 3 with each other. Coupling device according to Claim 1, characterized in that the male frame 2 and the female frame 3 each have the shape of a triangle, the base of which is in the lower part of the coupling device 1 and the main vertex is in upper part of the coupling device 1. Method for coupling an agricultural tool to a three-point lifting system of an agricultural tractor comprising the following steps:
- a so-called male frame 2 of a coupling device 1 is mounted, said male frame 2 being provided with fasteners 20 to a three-point lifting system, on the three-point lifting system of a tractor and mounts a so-called female frame 3 of said coupling device 1, said female frame 3 being provided with fasteners 30 to an agricultural tool,
- the male frame 2 is positioned so that a hook 21 on its upper part is in a position projecting forward relative to the male frame 2,
- the hook 21 of the male frame 2 is brought closer to a hooking member 31 on the upper part of the female frame 3,
- the hook 21 of the male frame 2 is made to cooperate with the attachment member 31 of the female frame 3,
- The lifting system is actuated to bring the male frame 2 back to a vertical position; in doing so, the female frame 3 held to the male frame 2 by the hook 21 cooperating with the attachment member 31 pivots and approaches the male frame 2, guide means 5 guiding the female frame 3 towards a position of abutment of the female frame 3 against male frame 2,
- Once the female frame 3 attached to the male frame 2, it actuates locking means of a frame with the other.