WO2004077928A1

WO2004077928A1 - An implement coupling device

Info

Publication number: WO2004077928A1
Application number: PCT/GB2004/000785
Authority: WO
Inventors: Stanley Roberts
Original assignee: Stanley Roberts
Priority date: 2003-03-08
Filing date: 2004-03-01
Publication date: 2004-09-16

Abstract

An implement coupling for coupling a detachable implement (2) to the linkage of a tractor or other vehicle and/or to the front lifting or loading arms (3, 4, 5) of a tractor or other vehicle, comprising first mounting means (6) connected to or connectable to an implement to be raised by the vehicle and one or more lifting means (12) connected to or connectable to the three point linkage or linkages of the vehicle; wherein one of said mounting means or lifting means has in an upper region one or more upwardly extending mounting projections (17) engageable with one or more mounting apertures or recesses (14) in an upper region of the other lifting means or mounting means respectively, such that when the lifting means are raised towards the upper part of the mounting means said projections and apertures/recesses interengage to enable lifting of the mounting means causing surfaces of said mounting means and lifting means to abut, and releasable retaining means (8, 9), for holding the mounting means and lifting means together, characterised by the feature that the releasable retaining means comprises jaws or two spaced apart stop surfaces (8d, 9d) optionally locatable adjacent or against oppositely facing surfaces of said lifting means and mounting means when in abutment to retain such therebetween to prevent such moving apart, and at least one locating projection (8c, 9c) or recess (23) moveable with said jaws or stop surfaces to engage in at least one locating recess or projection respectively of said mounting means and lifting means to prevent the mounting means and lifting means moving parallel to each other.

Description

AN IMPLEMENT COUPLING DEVICE

The present invention relates to an implement coupling device for coupling a detachable implement to vehicle such as an agricultural implement to a tractor, and one which is preferably coupleable to the front lifting/loading arms of a tractor and front and/or lifting hitch or linkage of a tractor.

Known coupling devices are not entirely satisfactory since they can be difficult to interengage and the interconnection points are prone to wear and not particularly strong and they can be complex constructions which make them expensive and prone to breakdown. A search has revealed coupling devices in GB 2163034 and EP 1103171 which disclose relatively complicated constructions interconnectable by sliding, circular cross-section pins (prone to wear and blockage) engageable in close fitting apertures to hold together and it is believed such would be relatively expensive to produce and are only for connection to the front or rear three part linkage of a tractor. Further, there is a danger that only one of the interconnection means may engage.

It is an object of the present invention to provide an improved coupling device which is robust and economic to produce and which is preferably connectable to the front loader/lifting arms of an agricultural vehicle and/or the front or rear lifting linkage of a tractor.

According to a first aspect of the invention there is provided an implement coupling for coupling a detachable implement to the linkage of a tractor or other vehicle and/or to the front lifting or loading arms of a tractor or other vehicle, comprising first mounting means connected to or connectable to an implement to be raised by the vehicle and one or more lifting means connected to or connectable to the three point linkage or linkages of the vehicle; wherein one of said mounting means or lifting means has in an upper region one or more upwardly extending mounting projections engageable with one or more mounting apertures or recesses in an upper region of the other lifting means or mounting means respectively, such that when the lifting means is raised towards the upper part of the mounting means said projections and apertures/recesses interengage to enable lifting of the mounting means causing surfaces of said mounting means and lifting means to abut, and releasable retaining means for holding the mounting means and lifting means together, characterised by the feature that the releasable retaining means comprises jaws or two spaced apart stop surfaces optionally eatable adjacent or against oppositely facing surfaces of said lifting means and mounting means when in abutment to retain such therebetween to prevent such moving apart, and at least one locating projection or recess moveable with said jaws or stop surfaces to engage in at least one locating recess or projection respectively of said mounting means and lifting means to prevent the mounting means and lifting means moving parallel to each other.

Preferably, the or each lifting means has as said one or more projections at least one upwardly extending lifting lug having a flat surface facing the vehicle, in use, and said mounting means having an aperture for receiving said lifting lug with a flat face closest the vehicle in use and abuttable in the lifting position by said flat face of said at least one lug.

Preferably, the mounting apertures or recesses are of a greater depth than necessary to receive the mounting projections in a direction away from the sides of the mounting recesses or apertures which are in load-bearing abutment with the projections when the mounting means and lifting means are being raised (i.e. normally in a direction away from the vehicle). Preferably, the main surfaces of the mounting means and the or each lifting means which abut when in the coupled position are planar/flat and do not have any peripheral projections in a direction towards the other frame in their lateral regions or in their lateral and lower regions.

Preferably, one or more apertures or recesses of the mounting means are in a bracket or flange projecting towards the lifting means and over planar abutment surfaces preferably at right angles thereto.

Preferably, two releasable retaining means are provided preferably on the lifting means, each comprising two clamping or retaining jaws preferably mounted on the mounting means and each displaceable in opposite directions to clamp or retain between the two opposed faces thereof the oppositely facing surfaces of juxtaposed side parts of the mounting means.

Preferably, a plurality of similar lifting means are provided and each includes side parts spaced apart at a predetermined distance and to abut side parts of the mounting means also spaced apart at the same predetermined distance, and in which the thickness of said side parts of the plurality of mounting means is the same to enable each of said mounting means to be engaged to said lifting means.

Preferably, two lifting means are provided with a first mountable on the front lifting/loading arms of the vehicle and a second lifting means mountable on the front and/or rear lifting linkage or hitch of the vehicle and the mounting means is adapted to be connectable to both said first and second lifting means.

The mentioned feature of providing a plurality of similar parts enables the device of the present invention to form what might be considered a universal coupling in that many different implements with the mounting means may be lifted on the various front loading arms and/or front or rear lifting linkage of the vehicle fitted with the lifting means. Since the coupling ends of front loading arms of different vehicles vary the lifting means of the invention may be adapted to be connected to such to enable the connection of the various arms to be possible. Suitable frame members with connection apertures may be connected for such purpose.

Preferably the or each lifting means will be a frame with connection lugs or other in known manner for connection on the lifting arms and/or hitch of a tractor and presenting two spaced apart flat abutment surfaces in the same plane. Preferably the mounting projections are on the lifting means and extend above a flat plate extending in a direction at right angles to said plane of the abutment surfaces to be abuttable by the aperture and abutment forming flange frame. Preferably the mounting means will be parts which may be formed as a frame and/or such that when located on the implement to be attached, comprise two spaced apart abutment members with faces lying in the same plane (abuttable against the flat surfaces of the lifting means) and preferably said apertures or recesses will be provided by a flange extending at right angles to said plane and abuttable against the stop surfaces of the lifting means. The frame may be rectangular and preferably made of plate steel laser cut or otherwise to suitable shape for reasons of economy, and will have planar/flat surfaces without flanges extending towards the other frame in the lateral and bottom regions. Preferably the mounting frame will have a flange across top region extending towards the lifting frame and have said aperture or apertures therein and preferably two such spaced apart apertures will be provided and preferably having a flat surface, closest in use towards the lifting frame, abuttable by a preferably flat surface of a lug projecting upwardly from the top of the mounting frame - the abutting flat surfaces providing for stability and strength as the lugs and apertures can be of a significant dimension rather than simple circular section pins. The apertures in the top flange will be larger than necessary to accommodate the lugs of the lifting frame in a direction away from the lifting frame for ease of insertion. Preferably the tops of the projecting lugs will be rounded to also facilitate insertion and guidance of the lugs into the apertures.

In use when the lugs are inserted into the apertures of the mounting frame such may be in a slightly inclined position with the upper part of the lifting frame being away from the vehicle such that when said lifting frame is pivoted to extend more upwardly and preferably vertically, the flat abutment surfaces co-operate such that the flat abutment surfaces of the mounting frame and lifting frame move into abutment whereupon holding means carried by the lifting frame may be displaced to hold or clamp the two frames together - preferably by acting on or being located adjacent oppositely outward facing surfaces of the two abutting frames.

Preferably the means for holding the frames together will comprise clamping means preferably in the form of two L-shaped channel-like clamps displaceably mounted on the bottom cross piece of the lifting frame and having an outwardly extending channel section of generally U-shaped cross-section of a width just to accommodate the two lateral parts of the lifting and mounting frames to clamp such together when outwardly displaced by displacing means. Preferably a locating protrusion or projection preferably formed as part of the clamping means will extend between the limbs of the channel and be engageable in correspondingly shaped notches or recesses in the side parts of the lifting and mounting frames to prevent any relative movement in a parallel plane. Thus the mounting means is lifted by the lifting means and secured against moving apart transversely by the clamping means and parallely by the protrusions. Preferably, two releasable retaining means such as clamping jaws or stop surfaces will be displaceable together such that if one is prevented from being displaced, the other will not move.

Preferably the means for displacing the clamping parts or members will be energised by the pneumatic or hydraulic fluid displacement means of the vehicle and preferably such will comprise a reversibly drivable piston-cylinder arrangement mounted on the lifting frame and displacing a cam surface or spiral provided for each clamping means and carried by an axle. By rotating a pivot connecting arm connected to an axially rotatable axle carrying the cam surfaces, driving pins displaceable against the cam surfaces/spirals and in turn connected to the clamping members, displacement the clamping members is effected outwardly for clamping the frames together or inwardly for releasing such. Preferably a manually operable lever can also be connected to said axially rotatable rod or axle for use, as required.

According to a further aspect of the invention, there is provided an implement coupling for coupling a detachable implement to the front and/or rear three point lifting linkage or hitch of a tractor or other vehicle and to the front lifting or loading arms of a tractor or other vehicle, comprising mounting means connected to or connectable to an implement to be raised by the vehicle, first lifting means connected to or connectable to front loading arms of the vehicle and engageable with said mounting means to enable the implement to be raised by the vehicle, and second lifting means connected to or connectable to the front and/or rear linkage of the vehicle and engageable with said mounting means to enable lifting.

Preferably the second lifting means is larger than the first lifting means to enable connection to the front or rear lifting linkage of a tractor. Preferably, the first and second lifting means each have means for holding the respective lifting means and the mounting means together. Also, preferably the mounting means has one or more first locating notches or recesses for receiving parts of means for holding the mounting means and the first lifting means together to prevent relative movement, and said mounting means also has spaced from said first one or more locating notches or recesses and at a different level, one or more second locating notches or recesses for receiving parts of means for holding the mounting means and the second lifting means together to prevent relative movement. Further, preferably second locating notches or recesses are located normally above said first locating notches or recesses. Preferably the first and second lifting means and each of the mounting means each comprise a frame having lateral upwardly extending side frame members which have the same spacing apart and have the same thickness to enable engagement by the retaining means to enable ready use on different implements.

As mentioned earlier; the coupling device of the present invention may be readily usable on the front loading arms of a tractor and/or on the rear three point linkage or hitch of a tractor by providing a suitably dimensioned and notched mounting means to accommodate for the difference in height of the lifting means on respective front forks or lifting arms and the lifting means on the three point linkage.

The present invention is also intended to cover a set of parts which may be added to existing implements and/or vehicles to adapt such to be in accordance with the present invention. The present invention is also intended to cover an implement and/or tractor or other vehicle whenever adapted according to the invention. According to a further aspect of the present invention there is provided an implement coupling for coupling a detachable implement to the three point linkage of a tractor or other vehicle and/or to the front lifting or loading arms of a tractor or other vehicle, comprising first mounting means connected to or connectable to an implement to be raised by the vehicle and second lifting means connected to or connectable to the three point linkage or linkages lifting of the vehicle; wherein one of said mounting means or lifting means has in an upper region one or more upwardly extending mounting projections engageable with one or more mounting apertures or recesses in an upper region of the other lifting means or mounting means respectively, such that when the lifting means is raised towards the upper part of the mounting means said projections and apertures/recesses interengage causing surfaces (preferably planar) of said mounting means and lifting means to abut, and releasable retaining means, preferably on the lifting means, for holding the mounting means and lifting means together, characterised by the feature that a) said mounting apertures or recesses are of a greater depth than necessary to receive the mounting projections in a direction away from the sides of the mounting recesses or apertures which are in load-bearing abutment with the projections when the mounting means and lifting means are being raised (i.e. normally in a direction away from the vehicle); and/or b) the main surfaces of the mounting means and lifting means which abut when in the coupled position are planar or flat and do not have any peripheral projections in a direction towards the other frame in their lateral regions or in their lateral and lower regions; and/or c) the or each lifting means has as said one or more projections at least one upwardly extending lifting lug having a flat surface facing the vehicle, in use, and said mounting means having an aperture for receiving said lifting lug with a flat face closest the vehicle in use and abuttable in the lifting position by said flat face of said at least one lug; and/or d) in which the one or more apertures or recesses of the mounting means are in a bracket or flange projecting towards the lifting means and over planar abutment surfaces preferably at right angles thereto; and/or e) that said releasable retaining means comprises clamping or retaining jaws, preferably mounted on the mounting means, and displaceable to clamp or retain between two opposed faces thereof, oppositely directed surfaces of the juxtaposed parts of the mounting means and the or each lifting means; and/or f) a plurality of said mounting means are provided for different implements and each mounting means comprises a frame which are so dimensioned and/or spaced as to be engageable by said retaining means to enable many mounting means to be lifted by said lifting means; and/or g) two lifting means are provided with a first lifting means being mountable on the front lifting/loading arms of the vehicle and at least a second lifting means mountable on the front and/or rear three point lifting linkage(s) of the vehicle and the mounting means is connectable to both said first and at least second lifting means.

A le**-*

to the present invention there is provided an implement coupling for coupling a detachable implement to the three point linkage of a tractor or other vehicle and/or to the front loading or lifting arms of a tractor or other vehicle, comprises at least one mounting means connected to or connectable to an implement to be raised by the vehicle and one or more lifting means connected to or connectable to the front lifting arms and/or the three point linkage or linkages of the vehicle; wherein the lifting means has in an upper region one or more upwardly extending mounting projections engageable with one or more mounting apertures open from below in an upper region of the mounting means such that when the lifting means is raised towards the upper region of the mounting means, said projections enter said apertures to enable lifting of the mounting means with continued raising causing said mounting means to be suspended on the lifting means with surfaces said two means being in abutment, and releasable retaining means for holding the mounting means and lifting means together, characterised by the feature that the releasable retaining means comprise(s) jaws or at least two spaced apart stop surfaces optionally displaceably locatable adjacent or against oppositely facing surfaces of said lifting means and mounting means when in abutment to retain such therebetween to prevent such moving apart, and at least one locating projection or recess moveable with said jaws or stop surfaces to engage in at least one locating recess or projection, respectively, of said mounting means and lifting means to prevent the mounting means from disengaging from the projections of the lifting means by parallel relative movement of said means.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which:-

Fig. 1 is a schematic illustration of part of a mounting frame connectable to an implement to be lifted by a tractor and a lifting frame connectable to the front lifting arms of a tractor and/or the front and/or rear three point linkage of a tractor (the clamps and displacement means not being shown in detail nor is the implement nor the tractor);

Fig. 2 is a fragmentary detail of a lifting lug;

Fig. 3 is a fragmentary detail of a corner of the lifting frame showing one of two elongate apertures in which a guidance pin of one of two clamping members drivable by a cam surface/spiral may be located, and showing a mounting lug on which the pivot axle carrying said spirals is rotatably mountable;

Fig. 4 is a side elevation of Fig. 3;

Fig. 5 is an enlarged perspective view of the two cam surfaces/spirals shown separate from one lifting frame together with the axle thereof which is pivotably mountable in mounting lugs or projections A and B of Figs. 1 and 3;

Fig. 6 is an end elevation of the cam surfaces and axle Fig. 5 and;

Fig. 7 is a side elevation of the displacement means of Figs. 5 and 6 (the pneumatic displacing piston cylinders being illustrated in Fig. 11 );

Fig. 8 is a perspective view of one of the two oppositely facing L-shaped clamping members with the retention and guiding pin for being driven by the cam in its rearwardly extending region being shown separately;

Fig. 9 is a fragmentary perspective detail of the left-hand corner of a lifting frame with one of clamping members being shown with its lower shank forming an inverted U section channel slideable on the horizontal of the lifting frame.;

Fig. 10 is a section on the line X-X of Fig. 8 showing the construction of the clamping member in more detail; and Fig. 11 is a partial schematic perspective view of a coupling device similar to that of Figs. 1 to 10 showing a first mounting means mounted on the front lifting arms of a tractor and a second higher mounting means for mounting on the three point linkage and an implement mounting means for attachment to an implement and liftable by either of said mounting means;

Fig. 12 is an enlarged perspective view of the assembled first lifting means of Fig. 11 with front loader arms indicated;

Fig. 13 is an enlarged perspective view of the assembled second lifting means of Fig. 11 with connections for a three point linkage (not shown); and

Fig. 14 is an enlarged perspective view of the second lifting means and lifting means of Figs. 11 and 13 but from the rear;

Fig. 15 is a perspective view from the tractor side (not shown) showing the mounting member/implement frame - of an implement coupling with a driven member to be mounted on the implement, and the lifting member/tractor frame to be connected to a tractor with the drive member mounted centrally thereon, and including a pivotally mounted shaft (60) with a control cam (61 );

Fig. 16 is a perspective view, showing separately, the driven member (left) and drive member (right) between mounting uprights and spaced apart and turned to show the end faces;

Fig. 17 is a vertical schematic section through the assembled drive means of the coupling.

An implement coupling device 1 as illustrated for coupling a detachable implement (2, schematically in Fig. 11 ) to the three point linkage of a tractor (which is normally at the rear but may be at the front) and/or to the front loader or lifting arms 3,4,5 in Fig. 11 of a tractor (not shown) and comprises a right angular, generally inverted U-shaped mounting frame 6 connectable by suitable means (not shown) to an implement to be lifted 2 in Fig. 11 (such as a lifting spike) and is slightly spaced therefrom to provide clearance for retaining means or clamping members 8,9. The mounting frame 6 is formed of rectangular section (possibly formed from a single sheet by laser cutting) so as to present a planar upwardly/extending surface 10 to abut a planar, upwardly extending surface 11 of a similarly formed rectangular lifting frame 12. A second and larger lifting frame 12 in Figs. 11 ,13 and 14 is provided for connection on the rear three point linkage of the tractor and will have similar features to frame 12. In Figs. 1 ,11 and 14 the surfaces 10 of the mounting frame 6 has two pairs of oppositely located notches or recesses 23, and 23a - one 23a being lower than the others 23 to accommodate the necessarily taller rear lifting frame 12a - Fig. 11.

The mounting frame 6 has a bar section 13 of rectangular section welded across its top and in which notches or recesses 14,15 are provided having for strength and location large flat surfaces 14a, 15a closest to the lifting frame 12 for abutment with the flat surfaces 16 of two upwardly extending projections or lugs 17 of the lifting frame 12 (having rounded end surfaces for guidance ease of engagement into the apertures 14,15). The apertures 14,15 are of a width to closely receive the lugs 17 but are oversize in a direction away from said surfaces 14a so that when the lugs 17 are moved upwardly from below and toward the apertures 14,15 such are more readily locatable.

The similarly formed but rectangular lifting frame 12 formed of plate steel to present planar surfaces 11 to be adjacent the mounting frame 6 has a cross bar 18 welded at its top extending away from the planar surfaces 11 and towards the vehicle in use and has the two projections or lugs 17 with rounded ends 17a extending upwardly therefrom.

It will be noted that the two lateral sides 10a and 11 of each of the mounting and lifting frames 6,12 each lie in a single plane and do not have any peripheral projections extending towards the other frame 12,6 and this facilitates location and juxtaposition of the surfaces of lugs 17 in apertures 14,15 as relative lateral movement of lifting frame 12 is not impeded.

The two retaining means in the form of two so-called L-shaped clamping members 8,9 are displaceably slideable on the upper surface 12c of the bottom cross-piece of the lifting frames 12,12a and lower flanges 8a,9a sliding in retaining and guide recesses 22a in lugs 27 with the lower side flanges 8a of clamping members 8, also retaining such in position thereon. Members 8,9 each have a cam follower pin 8b,9b extending rearwardly from their rear lower faces to enable such to be displaceable by each being engaged in a spiral groove or cam surface member 19,20 each fixedly mounted on a pivotable axle 21 in turn mounted on the bottom cross-pieces 12b of the lifting frames 12, 12a. The axle 21 is pivotably mountable in lugs 22 (Figs. 3,4) on the lifting frame 12 as will be readily apparent to those skilled in the art. The bottom cross-piece 12b has elongate apertures 12d in which part of pin 8b,9b extends and between the bottom flanges 8a of end of the L-shaped clamping members 8,9 to which is secured so as to slidably retain the clamping members 8,9 in position. The cams and follower pins 8b,9b are such that the clamping members 8,9 are displaceable in opposite directions on rotation of axle 21. Protrusions or projections 8c,9c are formed in the upwardly extending end wall of members 8,9 and are locatable in recesses 23,23a of frames 6,12 when abutting each other to prevent relative parallel movement of frames 6,12 when clamped together. When mounting frame 6 is suspended on lugs 17 with the surfaces 10a abutting surfaces 11 and the clamping members 8,9 are displaced outwardly and away from each other, the upwardly extending side walls 8d,9d, have facing surfaces 8e,9e which are spaced to locate adjacent or in abutment with the oppositely outer facing surfaces of side members 10a and surfaces 11a of member 12 to prevent such moving apart - the projections 8c,9c engaging in recesses 23,23a preventing parallel movement of mounting frame member 6 relative to lifting frame 12. Thus, whilst the side walls 8d,9d of each of the "clamping" members do not actually move towards each other as they are fixed, they locate either side of side members 10a and 11a to sandwich such therebetween.

When a plurality of mounting means or frames 6 are provided as is intended, sides 10a will be at the same distance apart and of the same thickness with the same recesses 12 and/or 23a to enable ready interchange and flexible use.

A manually operable lever 21a may be connected to shaft 21 to enable manual displacement of cam surfaces 19,20 and the clamping jaws 8,9, if desired.

In use, the mounting frame 6 connected to an implement (7, in Fig. 11 ) (such as a pair of lifting spikes for bale handling) may rest on the ground and possibly be slightly inclined with top more remote than its base and the lifting frame 12 mounted on the vehicle (not shown) is brought towards the mounting frame 6 with the lugs 17 beneath the upper cross-piece 18 of the mounting frame 6 and aligned generally with the apertures 14,15 such that on raising the lugs 17 such enter the apertures 14,15 with ease because there is extra clearance in a direction away from surfaces 14a,15a and because of the rounded noses 7a whereupon, on lifting, the originally inclined lifting frame 6 moves towards the vertical or more upwardly extending such that the flat surfaces 16 of the lugs 17 and 14a of the recesses 14 abut in stable strong relationship and the components are such that the flat faces 10a of the mounting frame 6 rotate towards the flat faces 11 of the lifting frame 12 and lie in abutment therewith with the lower flanges 8a of the clamping members 8,9 straddling the lower cross- pieces 12a of the frame 12. It is to be noted the lower ends of sides 10a define a free space therebetween and are not interconnected. Subsequently, displacing means for rotating the axle 21 and the cam surfaces 19 comprising a hydraulic/pneumatically operable piston cylinder 24 connected by a flexible piping (not shown) to the power source of the vehicle are energised so as to rotate the axle 21 and cam surfaces 19 thereby causing the pins 8d,9d slideables thereagainst and connected to the clamping members 8,9 to be displaced outwardly together such that the channel section and upwardly extending jaws 8d,9d of the channels of the clamping members 8,9 each locate on opposite sides of the outer surfaces 10a of the mounting frame 6 and surfaces 11a of the lifting frame 12 to retain or "clamp" such therebetween. The protrusions 8c,9c are located extendably between the uprights 8d,9d of each of the clamping member 8,9 and have rounded ends for guidance and will engage in a notch or recess 23,23a in each of the side frames of the lifting frame 12 and mounting frame 6 for additional secured location against parallel movement. By maintaining the pressure in the piston-cylinder 24, the frames 6,12 of coupling device 1 are held together and suitable for use, as desired. To release the implement 7 such is lowered to the ground the piston-cylinder 24 operated so as to move the clamps 8,9 inwardly out of engagement with the side frames and then the lifting frame 12 lowered to withdraw the lugs 17 from the recesses 14,15 and the vehicle moved away, as appropriate.

The "clamping" arrangement is such as to provide a geared clamp which resists opening is strong and one clamp cannot engage without the other engaging.

The assembled coupling device shown in Figs. 11-14 is very similar and thus has the same reference numerals for the same or similar parts. The mounting of the lifting frame on the tractor is illustrated in that pairs of side lugs or flanges 12e (only one shown) extend from opposite ends of the rectangular mounting frame 12 and to which the front lifting arms 3 of the tractor are pivotally mounted. The lugs or flanges 12e will be spaced to suit the loader arms. Also, L-shaped links 4 are pivotally connected between arms 3 and frame 12 and are displaceable via pivotally connected piston rods 5 of the loader arms of a tractor (not shown). The mounting frame 6 does not have a lower horizontal cross-piece and is connectable to the implement frame 7 in known manner.

It will be appreciated that the same considerations apply in respect of the rear lifting frame 12a which has suitable connection points for the three point linkage. The invention provides the advantage of enabling connection of the mounting frame 6 to the front and/or rear three point linkage of the tractor and also to the front loading arms.

The spacings and thickness dimensions of the side members of the front mounting frames 6 are all the same to enable many different implements to be used.

It will be noted that with abutment, the recesses 23 of the lifting frame 12 align with the recesses 23/23a of the mounting means 6 and the projections or protrusions 8c,9c of the two jaws 8,9 on movement apart, extend thereacross and thereinto to interlock the frame 12 and mounting means 6 against parallel movement i.e. movement in a direction transversely to the plane of abutment of frame 12 and mounting means 6 is prevented by sides 8d,9d and projections 8c,9c engage in recesses 23,23a to prevent the mounting means moving parallel to the lifting means to prevent such lifting off the lugs 17.

It is to be appreciated the three points of connection 6a of the rear lifting means 12a in Figs. 11 and 13 are necessarily spaced apart vertically greater than the connection points for the loader arms of front lifting means 12 because of the greater spacing of the connection points of the tractor's three point lift linkage and hence the need for mounting means 6 to be of a height to accommodate such and thus to have a taller lifting means and greater spaced recesses 23a.

It will be appreciated that the coupling device, as mentioned, provides a simple and reliable construction which is robust and easy to produce and reliable in operation. It also enables the retaining or securing means of the lifting means to be connectable to a hydraulic circuit of the vehicle so as to be energisable by the vehicle user from the normal driving position to engage with the mounting means. Because of the nature of the suspension and the open unimpeded nature of the abutment surfaces and/or the oversizing of the lug-receiving apertures and/or their being open from below, either individually or in combination, such means the mounting means and implement can be picked-up or detached even if not on horizontal ground. Also, the engagement is clearly visible.

A drive coupling is shown in the drawings which is to be used with an implement coupling devices 47, 57 similar to that as disclosed in Figs. 1-14.

In Figs. 15 to 17 the drive coupling comprises a rotatable drive member in the form of a circular disc 31 having three equally spaced, identical apertures or slots 32 therein with the apertures 32 tapering or reducing in dimension in an upstream direction with respect to the normal direction of rotation (arrow 33) of the disc 31. The disc 31 is securely mounted on a rotary shaft 34 to be rotatable therewith and shaft 34 is rotatably mounted within two sets of bearings 35, 36 and held captive therein by circlips 37. The bearings 35, 36 in turn are securely mounted in an axially displaceable coaxial cylinder 38 with aperture end wall 38A and which is slideable in telescopic manner in both directions along the axis of rotation 39 within an outer coaxial cylinder 40 and displaceable by means of force exerted forwardly/rearwardly on a downwardly extending projection 41 running in a slot 42 in the outer housing 40. The bearings 35, 36 abut against steps (not shown) in displaceable cylinder 38 and held therein by circlips 37 on shaft 34, the end of shaft 34 is splined at 34A for connection to the PTO shaft of a tractor (not shown).

The outer cylinder 40 is secured between two vertical uprights 45, 46 by welding with rod connectors (not shown) and which are secured uprightly centrally to a lifting frame 47 (centrally of 12 or 12A or of 47A or 57A) of an implement coupling which is to be mounted on the three point lifting linkage of a tractor (not shown).

Spring biasing means 49, 50 are located either side of the outer cylinder 40 and each comprise a rod 51 with an enlarged disc-like head 51 A at one end slideable in a cylinder 52 and biased by springs 53 to move to be urged towards the rotary plate disc 31 and with said rods 51 extending through a guide aperture in the cylinder end 52A (against which the end of compressing spring 53 abuts) and through apertures 54A in a displacing bar 54 and is held therein by nuts 55 on threaded ends of rods 51 so that the bar 54 and rods 51 move together. The horizontal displacing bar 54 thus interconnects the two spring biasing means 49, 50 so as to be moved thereby in one direction whereupon it abuts against centrally located, downwardly extending projection 41. The spring biasing means 49, 50 move projection in slot 42 also thus move cylinder 38 and thus shaft 34 and disc 31 axially to the left i.e away from the tractor and towards the other part, the driven part or member 50 of the drive coupling as will be described later. The bar 54 is guided in cut-outs 57 in the uprights 45, 46.

A driven means or member 56 is to be located on an implement (not shown) which is to be attached to the tractor, and preferably be connected to the drive train thereof e.g. gearbox, of the implement and preferably be located generally in the space defined by the implement mounting frame 57. Frame 57 has apertures 58 for receiving projections 59 of the lifting frame 57 which when engaged and raised, cause faces 47A and 57A to abut or be juxtaposed and then two spaced clamping means (71 in Fig. 15) are engaged by spiral cam surfaces carried by end members 60A, 60B on either side of the frames 47, 57 to hold faces 47A and 57A together.

When the lower end 62A of arm 62 is acted on by cam 61 to move it clockwise, the upper end 62B pushes projection 41 against displacing bar 54 causing such to be displaced to the right and against the bias action of springs 53. This results in displacement of shaft 34 and disc 31 away from driven member 56. On release by cam 61 , the springs 53 via rods 51 , bar 54 and projection 41 , cylinder 38 and shaft 34, return the driving disc 31 back into engagement with the drive member 56 as will be described.

The axial displacement of shaft 34 when connected to the PTO shaft or other auxiliary drive means, is enabled by suitable known means, such as a telescopic coupling.

The driven part or member 56 comprises a disc 63 fixed on the end of a rotary shaft 64 to rotate therewith and shaft 64, has splines to connect with the drive of the implement (not shown). Shaft 64 is rotatably mounted on rotary bearings 65, 66 retainedly mounted against steps/shoulders 87A, 87B in cylinder 67 itself secured in housing 68 having side securing frames 69 for mounting on rubber resilient mounts (not shown) with play for facilitating coupling with disc 31.

The disc 63 has three equally spaced rod-like/cylindrical projections or engaging pins 70 at the same radial distance as each other from the centre and an axis of rotation (similar to apertures 32) which when engaged with disc 31 is aligned with its axis.

When the axes are aligned and the discs 31 , 63 are brought together by the spring biasing means 49, 50, the apertures 32 of disc 31 are not yet being rotated by the tractor will engage and capture the pins 70 or, if the pins 70 are not aligned with the apertures 70, 32 they will be abutted by surface of disc 31 and then upon rotation of disc 31 , they will be captured by the apertures. When the disc 31 is caused to be rotated after engagement, the disc 63 on shaft 64 is caused to rotate thus driving the mechanism of the implement to which it is connected in use. As mentioned, the elongate aperture 32 are large at one end to facilitate such initial location around the pins 70 and then, with continued rotation, the apertures 32 engage the pins more closely at their reduced- dimension ends to drive such.

Thus the disc 31 is normally biased in a direction away from the uprights 45, 46 and into engagement with disc 63 i.e. towards the disc 63 of the driven member 56 when juxtaposed. However, during juxtaposition of the drive and driven members 31 , 63 and prior to such being inter-engaged, the displacing bar 54 will have been moved rearwardly towards the tractor by means of the pivotably mounted arm 62 which is acted upon at its opposite lower end 62A by the cam 61 on the rotatable clamp means displacing shaft 60. Thus, when the coupling parts 47, 57 have been clamped together by clamps 71 the cam 61 then rotates, on continuous movement of shaft 60, to release the pressure on the lower end 62A of the displacing arm 62 enabling the spring bias means 49, 50 to push the enlarged ends 51 A, 51 B thereof and rods 51 forwardly and hence the disc 31 of the drive of the member forwardly along its axis of rotation 39 (but not yet rotating a consequence of it previously having been connected to the operating drive shaft of the tractor, for example, such that the disc 31 then contacts the pins 70 of the disc 61 to be driven and with commencement of rotation, if not already engaged, such will cause such pins 61 to be engaged in the tapered apertures 32 thereby causing the connected implement to be driven. Also, each aperture 32 has a rounded hollow or a recessed or inclined surface 32A at the leading end of each aperture or recess and running thereinto to facilitate location of projection into the recess or aperture and to facilitate disengagement of the pins especially when the drive is stopped and the movement of the driven implement drive train continues for a while.

For disengagement, the mentioned cam means 61 on the drive shaft 60 of the clamping means is initially moved to act on the displacing arm 62 to pivot and move such so as to disengage the drive and driven members 31 , 56 and, with continued movement of the shaft 60, the clamping means are caused to release the parts 31 , 56 of the coupling device whereupon then the implement coupling parts 47, 57 may be disengaged as desired by manoeuvring the tractor or the like.

When combined with the implement coupling device, the clamping of the two parts thereof together and then the release to enable the biasing means to urge the drive and driven members together is preferably effected one after the other but as a continuous operation with the continuous rotation of the shaft 60 - thus, in effect, as a single control operation.

It will be appreciated that a very simple and effective and reliable coupling is provided, which is robust and economic to produce and can be operated from the cab of a tractor or like. The present application is also intended to obtain protection for the drive coupling on its own.

The coupling does not use splines for the actual coupling and the free ends of the projections, e.g. pins, face towards the other coupling when uncoupled and are spaced from the connected supporting rotary shaft.

Claims

1. An implement coupling for coupling a detachable implement to the three point linkage of a tractor or other vehicle and/or to the front lifting or loading arms of a tractor or other vehicle, comprises at least one mounting means connected to or connectable to an implement to be raised by the vehicle and one or more lifting means connected to or connectable to the front lifting arms and/or the three point linkage or linkages of the vehicle; wherein one of said mounting means or lifting means has in an upper region one or more upwardly extending mounting projections engageable with one or more mounting apertures or recesses in an upper region of the other lifting means or mounting means respectively, such that when the lifting means are raised towards the upper part of the mounting means said projections and apertures/recesses interengage to enable lifting of the mounting means causing surfaces of said mounting means and lifting means to abut, and releasable retaining means for holding the mounting means and lifting means together, characterised by the feature that the releasable retaining means comprises jaws or two spaced apart stop surfaces optionally locatable adjacent or against oppositely facing surfaces of said lifting means and mounting means when in abutment to retain such therebetween to prevent such moving apart, and at least one locating projection or recess moveable with said jaws or stop surfaces to engage in at least one locating recess or projection, respectively, of said mounting means and lifting means to prevent the mounting means and lifting means moving parallel to each other.

2. A coupling as claimed in claim 1 , in which said lifting means has as said one or more projections at least one upwardly extending lifting projection or lug having a flat main surface on its side normally most adjacent the vehicle, in use, and said mounting means having an aperture for receiving said lifting lug with a flat side defining face in use closest the vehicle in use and abuttable in the lifting position by said flat face of said at least one lug.

3. A coupling as claimed in claim 1 or 2, in which said mounting apertures or recesses are of a greater depth than necessary to receive the mounting projections in a direction away from the sides of the mounting recesses or apertures which are in load-bearing abutment with the projections when the mounting means and lifting means are being raised (i.e. normally in a direction away from the vehicle)

4. A coupling as claimed in any of claims 1 or 3, in which the main surfaces of the mounting means and the or each lifting means which abut when in the coupled position are planar or flat or lie in a plane and do not have any peripheral projections in a direction towards the other frame in their lateral regions or in their lateral and lower regions.

5. A coupling device as claimed in any of claims 1 to 4, in which the one or more apertures or recesses of the mounting means are in a bracket or flange projecting towards the lifting means and over planar abutment surfaces.

6. A coupling as claimed in claim 5, in which the flange project at right angles to the planar abutment surfaces.

7. A coupling device as claimed in any of claims 1 to 6, in which two said releasable retaining means are provided each comprising two clamping or retaining jaws mounted on the mounting means and each displaceable in opposite directions to clamp or retain between the two opposed faces thereof, the oppositely facing surfaces of juxtaposed side parts of the mounting means and the or each lifting means.

8. A coupling device as claimed in any of claims 1 to 7, in which a plurality of similar lifting means are provided and each includes side parts spaced apart at a predetermined distance and to abut side parts of the mounting means also spaced apart at the same predetermined distance, and in which the thickness of said side parts of the plurality of mounting means is the same to enable each of said mounting means to be engaged to said lifting means.

9. A coupling as claimed in any of claims 1 to 8, in which two lifting means are provided with a first lifting means being mountable on the front lifting/loading arms of the vehicle and a second lifting means mountable on the front and/or rear three point linkage or hitch of the vehicle and the mounting means is connectable to both said first and second lifting means.

10. An implement coupling for coupling a detachable implement to the three point linkage of a tractor or other vehicle and/or to the front lifting or loading arms of a tractor or other vehicle, comprising first mounting means connected to or connectable to an implement to be raised by the vehicle and second lifting means connected to or connectable to the three point linkage or linkages lifting of the vehicle; wherein one of said mounting means or lifting means has in an upper region one or more upwardly extending mounting projections engageable with one or more mounting apertures or recesses in an upper region of the other lifting means or mounting means respectively, such that when the lifting means is raised towards the upper part of the mounting means said projections and apertures/recesses interengage causing surfaces (preferably planar) of said mounting means and lifting means to abut, and releasable retaining means, preferably on the lifting means, for holding the mounting means and lifting means together, characterised by the feature that a) said mounting apertures or recesses are of a greater depth than necessary to receive the mounting projections in a direction away from the sides of the mounting recesses or apertures which are in load-bearing abutment with the projections when the mounting means and lifting means are being raised (i.e. normally in a direction away from the vehicle); and/or b) the main surfaces of the mounting means and lifting means which abut when in the coupled position are planar or flat and do not have any peripheral projections in a direction towards the other frame in their lateral regions or in their lateral and lower regions; and/or c) the or each lifting means has as said one or more projections at least one upwardly extending lifting lug having a flat surface facing the vehicle, in use, and said mounting means having an aperture for receiving said lifting lug with a flat face closest the vehicle in use and abuttable in the lifting position by said flat face of said at least one lug; and/or d) in which the one or more apertures or recesses of the mounting means are in a bracket or flange projecting towards the lifting means and over planar abutment surfaces preferably at right angles thereto; and/or e) that said releasable retaining means comprises clamping or retaining jaws, preferably mounted on the mounting means, and displaceable to clamp or retain between two opposed faces thereof, oppositely directed surfaces of the juxtaposed parts of the mounting means and the or each lifting means; and/or f) a plurality of said mounting means are provided for different implements and each mounting means comprises a frame which are so dimensioned and/or spaced as to be engageable by said retaining means to enable many mounting means to be lifted by said lifting means; and/or g) two lifting means are provided with a first lifting means being mountable on the front lifting/loading arms of the vehicle and at least a second lifting means mountable on the front and/or rear three point lifting linkage(s) of the vehicle and the mounting means is connectable to both said first and at least second lifting means.

11. A coupling device as claimed in any of claims 1 to 10, in which each lifting means is a rectangular frame with connection lugs for connection on the front loading lifting arms and/or three point linkage of a tractor and presents two spaced apart flat abutment surfaces in the same plane.

12. A coupling device as claimed in claim 1 to 11 , in which mounting projections are on each lifting means and extend above a flat plate extending in a direction at right angles to said plane of the abutment surfaces to be abuttable by the aperture and abutment forming flange frame.

13. A coupling device as claimed in claim 1 to 12, in which the mounting means are parts which may be formed as a frame and/or such that when located on the implement to be attached, include two spaced apart abutment members with faces lying in the same plane (abuttable against the flat surfaces of the lifting means).

14. A coupling device as claimed in claim 1 to 13, in which said apertures or recesses are provided by a flange extending at right angles to said plane and abuttable against the stop surfaces of the lifting means.

15. A coupling device as claimed in claim 1 to 14, in which the mounting means or frame is rectangular and made of plate steel welded together or cut as a shaped member.

16. A coupling device as claimed in claim 1 to 15, in which the mounting means and lifting means each comprise a frame or at least two spaced apart engageable or clampable members having planar/flat surfaces without flanges extending towards the other frame or members in the lateral and bottom regions.

17. A coupling device as claimed in claim 1 to 16, in which a flange across top region extends towards the lifting frame and has said aperture or apertures therein and preferably two such spaced apart apertures.

18. A coupling device as claimed in claim 1 to 16, in which each said aperture has a flat surface, closest in use towards the lifting frame, abuttable by a preferably flat surface of a lug projecting upwardly from the top of the mounting frame.

19. A coupling device as claimed in claim 1 to 14, in which the apertures in the top flange will be larger than necessary to accommodate the lugs of each lifting frame in a direction away from the lifting frame for ease of insertion.

20. A coupling device as claimed in claim 1 to 19, in which the tops of the projecting lugs are rounded to also facilitate insertion and guidance of the lugs into the apertures.

21. An implement coupling for coupling a detachable implement to the front and/or rear three point linkage of a tractor or other vehicle and to the front lifting or loading arms of a tractor or other vehicle, comprises mounting means connected to or connectable to an implement to be raised by the vehicle, first lifting means connected to or connectable to the front lifting arms of the vehicle and engageable with said mounting means to enable the implement to be raised by the vehicle, and second lifting means connected to or connectable to the front and/or rear three point linkage of the vehicle and engageable with said mounting means to enable lifting.

22. A coupling as claimed in claim 21 , in which the second lifting means is larger than the first lifting means to enable connection to the front and/or rear linkage of a tractor.

23. A coupling device as claimed in claim 21 or 22, in which the first and second lifting means each have means for holding and locating the respective lifting means and the mounting means together.

24. A coupling device as claimed in any of claims 21 to 23, in which the mounting means has one or more first locating notches or recesses for receiving means for preventing the mounting means and the first lifting means moving parallel to each other, and said mounting means also has spaced from said first one or more locating notch or recesses at a different level, one or more second locating notches or recesses for receiving means for preventing the mounting means and second lifting means moving parallel to each other.

25. A coupling device as claimed in claim 24, in which second locating notches or recesses are located above said first locating notches or recesses.

26. A coupling device as claimed in any of claims 21 to 25, in which the first and second lifting means each comprise a frame which is so dimensioned and/or shaped as to enclose or partially define a space to also enable the connection of the front lifting arms of various existing known or other vehicles.

27. A coupling device as claimed in any of claims 21 to 26, in which each said first and second lifting means has one or more projections each comprising at least one upwardly extending lifting lug having a flat main surface on its side normally most adjacent the vehicle, in use, and said mounting means having an aperture for receiving said lifting lug with a flat side defining face in use closest the vehicle in use and abuttable in the lifting position by said flat face of said at least one lug.

28. A coupling as claimed in any of claims 21 to 27, in which said mounting apertures or recesses are of a greater depth than necessary to receiving the mounting projections in a direction away from the sides of the mounting recesses or apertures which are in load-bearing abutment with the projections when the mounting means and lifting means are being raised (i.e. normally in a direction away from the vehicle).

29. A coupling as claimed in any of claims 21 to 28, in which the main surfaces of the mounting means and lifting means which abut when in the coupled position are planar or flat and do not have any peripheral projections in a direction towards the other frame in their lateral regions or in their lateral and lower regions.

30. A coupling as claimed in any of claims 1 to 29, in which drive means are provided and operable such that the retaining means or clamping jaws are displaced at the same time in opposite directions.

31. A coupling as claimed in claim 30, in which a rotary drive rod carrying cam surfaces engaging said retaining means of jaws is reversibly drivable to displace said means or jaws.

32. A coupling device as claimed in claim 31 , in which the cam surfaces are arcuate slots in part cylindrical members.

33. A coupling device for coupling a detachable implement to a rear and/or front three point lifting linkage of a vehicle and/or to the front loading arms thereof substantially as herein described with reference to the accompanying drawings.

34. A tractor and implement whenever fitted with a coupling device as claimed in any of claims 1 to 32, having first and second lifting means mounted on the front loading arms and rear three point lifting linkage respectively and at least one implement fitted with said mounting means.

35. A kit of parts assemblable and/or mountable on a detachable implement to form mounting means and/or at least one lifting frame mountable on a tractor to form the coupling device as claimed in any of claims 1 to 33.

36. Mounting means as claimed in any of claims 1 to 35.

37. An implement coupling for coupling a detachable implement to the three point linkage of a tractor or other vehicle and/or to the front loading or lifting arms of a tractor or other vehicle, comprises at least one mounting means connected to or connectable to an implement to be raised by the vehicle and one or more lifting means connected to or connectable to the front lifting arms and/or the three point linkage or linkages of the vehicle; wherein the lifting means has in an upper region one or more upwardly extending mounting projections engageable with one or more mounting apertures open from below in an upper region of the mounting means such that when the lifting means is raised towards the upper region of the mounting means, said projections enter said apertures to enable lifting of the mounting means with continued raising causing said mounting means to be suspended on the lifting means with surfaces said two means being in abutment, and releasable retaining means for holding the mounting means and lifting means together, characterised by the feature that the releasable retaining means comprise(s) jaws or at least two spaced apart stop surfaces optionally displaceably locatable adjacent or against oppositely facing surfaces of said lifting means and mounting means when in abutment to retain such therebetween to prevent such moving apart, and at least one locating projection or recess moveable with said jaws or stop surfaces to engage in at least one locating recess or projection, respectively, of said mounting means and lifting means to prevent the mounting means from disengaging from the projections of the lifting means by parallel relative movement of said means.

38. An implement coupling as claimed in any of claims 1 to 37 in combination with a drive coupling or such drive coupling perse for drive interconnection with a drive-providing-apparatus (such as a tractor) with a driven implement (such as an agricultural implement attachable to a tractor) interconnectable by said implement coupling, said drive coupling comprising a rotatable drive member (preferably a plate with apertures) mountable on the drive-providing apparatus for receiving drive therefrom and a rotatable driven member (preferably a plate with projections) mountable on the implement for receiving drive from the drive member to drive the implement with said members being drivingly inter- engageable; wherein the rotatable drive member is displaceable (preferably axially) by displacement means for optionally displacing the driving member (preferably along its axis of rotation) towards and into engagement with and away from and out of engagement with said driven member when said mounting means and lifting means are juxtaposed and held together.

39. A combination as claimed in claim 38 in which the displacement means for the releasable retaining means or clamps for holding the lifting means and mounting means together are cam surface members on a rotatable axle, said axle has a cam located thereon forming control means such that when the frames are first put together, said cam is rotatable to displace a pivotal displacing arm to act to displace the driven member away from the drive member (and towards the tractor or like) so as to compress spring means or other biasing means and maintain such compression at least until the clamping means operate to hold the two mounting and lifting frames together whereupon, with continued movement of the cam such then releases the pivotal arm to enable the spring biasing means to move the drive member (preferably in the form of a circular disc with at least three equally spaced apertures therein), towards the driven member (preferably a similar circular rotary disc with at least three equally spaced cooperating projections thereon) and together into inter-engagement wherein the apertures capture the projections and move to engage such (at their preferably reduced width ends) for driving the driven member and the drive train of the implement connected thereto.

40. A coupling combination as claimed in claim 38 or 39, whenever in combination with a tractor or like and a drive implement attachment and operable such that when commencing operation, the displacement means is activated after the retaining means are engaged and when dismounting, the displacement means is operated to disengage the drive member and driven member prior to releasing the retaining means.