Quick-release fastener for construction machinery

Abstract

A device forming a coupler includes a coupler, or quick-release fastener (1) intended to be attached to a construction machine, such as a mechanical shovel, and a connection device (2) intended to be attached to a tool, such as a bucket (3), including at least one coupling trunnion (5), or hook respectively, which is intended to be coupled to at least one associated coupling hook, or trunnion respectively, of the quick-release fastener, and locking means intended to lock the quick-release fastener to the connection device, characterised in that it includes guide means (800, 810) intended to guide the pivoting movement of the quick-release fastener in relation to the connection device after coupling in order to lock the device, in particular self-centring means intended to allow relative self-centring of the quick-release fastener and the connection device.

Claims

1. A device forming a coupler comprising a coupler, or quick-release fastener (1), which is intended to be attached to a construction machine, such as a mechanical shovel, and a connection device (2), which is intended to be attached to a tool, such as a bucket (3), comprising at least one coupling trunnion (5), or hook respectively, which is intended to be coupled to at least one associated coupling hook, or trunnion respectively, of the quick-release fastener, and locking means intended to lock the quick-release fastener to the connection device, is characterised in that it comprises guide means (800, 810) intended to guide the movement, in particular the pivoting movement, of the quick-release fastener in relation to the connection device after coupling in order to lock the device, in particular self-centring means intended to allow relative self-centring of the quick-release fastener and the connection device, the guide means also guiding the trunnion towards the cavity of the hook.

2. The device according to claim 1, characterised in that the guide means comprise at least one support pin (800), in particular protruding laterally from at least one lateral flank of the connection device, and at least one associated guide section (810) of the at least one support pin, in particular formed in the quick-release fastener, in particular in a lateral flank (102) of the quick-release fastener, the guide section (810) being open at least towards the bottom and towards the outside of the quick-release fastener, preferably towards the bottom, towards the rear and towards the outside of the quick-release fastener.

3. The device according to claim 2, characterised in that the or each guide section (810) comprises a lower region (811), the lengthwise dimension of which, i.e. in the front-to-back direction of the quick-release fastener, tapers towards the top, followed by an upper region (812), the lengthwise dimension of which is substantially constant up to its top, the two regions being separated by an elbow (818) formed in a front wall of the section.

4. The device according to claim 3, characterised in that, seen in longitudinal section, the or each section (810) comprises a longitudinal wall (814) forming a substantially horizontal top, followed by a substantially vertical upper front wall (815), which is itself followed by a lower front wall (816) that extends towards the lower opening such as to form the elbow (818) with the upper front wall.

5. The device according to claim 1, characterised in that the quick-release fastener comprises at least one coupling hook (7) and the connection device at least one coupling trunnion (5), and the or each hook (7) comprises a part forming a rod and a part forming a coupling head which extends upwards from the end of the part forming a rod to thus define a respective cavity in which a trunnion of the connection device is intended to be inserted via a respective upper opening.

6. The device according to claim 5, characterised in that the cavity comprises a respective recessed area, in particular created in the front edge of the or each lateral flank of the quick-release fastener such that, when the trunnion is inserted in the receiving cavity or cavities through the upper opening or openings, the trunnion may be inserted in the or each recessed area, preferably over at least half of its transverse cross-section, i.e. over a sector with an angle of at least 180.

7. The device according to claim 2, characterised in that the quick-release fastener comprises at least one coupling hook (7) and the connection device at least one coupling trunnion (5), and the or each hook (7) comprises a part forming a rod and a part forming a coupling head which extends upwards from the end of the part forming a rod to thus define a respective cavity in which a trunnion of the connection device is intended to be inserted via a respective upper opening, and, when the or each hook is beneath the front trunnion, the or each support pin abuts against the lower front wall.

8. The device according to claim 2, characterised in that the quick-release fastener comprises at least one coupling hook (7) and the connection device at least one coupling trunnion (5), and the or each hook (7) comprises a part forming a rod and a part forming a coupling head which extends upwards from the end of the part forming a rod to thus define a respective cavity in which a trunnion of the connection device is intended to be inserted via a respective upper opening; and further characterised in that the cavity comprises a respective recessed area, in particular created in the front edge of the or each lateral flank of the quick-release fastener such that, when the trunnion is inserted in the receiving cavity or cavities through the upper opening or openings, the trunnion may be inserted in the or each recessed area, preferably over at least half of its transverse cross-section, i.e. over a sector with an angle of at least 180, and, when the or each hook is beneath the front trunnion, the or each support pin abuts against the lower front wall.

9. The device according to claim 2, characterised in that the quick-release fastener comprises at least one coupling hook (7) and the connection device at least one coupling trunnion (5), and the or each hook (7) comprises a part forming a rod and a part forming a coupling head which extends upwards from the end of the part forming a rod to thus define a respective cavity in which a trunnion of the connection device is intended to be inserted via a respective upper opening; and further characterised in that the cavity comprises a respective recessed area, in particular created in the front edge of the or each lateral flank of the quick-release fastener such that, when the trunnion is inserted in the receiving cavity or cavities through the upper opening or openings, the trunnion may be inserted in the or each recessed area, preferably over at least half of its transverse cross-section, i.e. over a sector with an angle of at least 180, and, as the driver of the bucket causes the quick-release fastener to turn in the correct direction in relation to the connection device, the pin moves along the lower front wall until the trunnion reaches its position in the or each recessed area of the or each cavity of the or each hook.

10. The device according to claim 2, characterised in that the quick-release fastener comprises at least one coupling hook (7) and the connection device at least one coupling trunnion (5), and the or each hook (7) comprises a part forming a rod and a part forming a coupling head which extends upwards from the end of the part forming a rod to thus define a respective cavity in which a trunnion of the connection device is intended to be inserted via a respective upper opening; and and, when the or each hook is beneath the front trunnion, the or each support pin abuts against the lower front wall, and, as the driver of the bucket causes the quick- release fastener to turn in the correct direction in relation to the connection device, the pin moves along the lower front wall until the trunnion reaches its position in the or each recessed area of the or each cavity of the or each hook.

11. The device according to claim 2, characterised in that the quick-release fastener comprises at least one coupling hook (7) and the connection device at least one coupling trunnion (5), and the or each hook (7) comprises a part forming a rod and a part forming a coupling head which extends upwards from the end of the part forming a rod to thus define a respective cavity in which a trunnion of the connection device is intended to be inserted via a respective upper opening; and further characterised in that the cavity comprises a respective recessed area, in particular created in the front edge of the or each lateral flank of the quick-release fastener such that, when the trunnion is inserted in the receiving cavity or cavities through the upper opening or openings, the trunnion may be inserted in the or each recessed area, preferably over at least half of its transverse cross-section, i.e. over a sector with an angle of at least 180 and, when the or each hook is beneath the front trunnion, the or each support pin abuts against the lower front wall, and, as the driver of the bucket causes the quick-release fastener to turn in the correct direction in relation to the connection device, the pin moves along the lower front wall until the trunnion reaches its position in the or each recessed area of the or each cavity of the or each hook.

12. The device according to claim 3, characterised in that the guide means comprise at least one support pin (800), in particular protruding laterally from at least one lateral flank of the connection device, and at least one associated guide section (810) of the at least one support pin, in particular formed in the quick-release fastener, in particular in a lateral flank (102) of the quick-release fastener, the guide section (810) being open at least towards the bottom and towards the outside of the quick-release fastener, preferably towards the bottom, towards the rear and towards the outside of the quick-release fastener, further characterised in that the quick-release fastener comprises at least one coupling hook (7) and the connection device at least one coupling trunnion (5), and the or each hook (7) comprises a part forming a rod and a part forming a coupling head which extends upwards from the end of the part forming a rod to thus define a respective cavity in which a trunnion of the connection device is intended to be inserted via a respective upper opening; and further characterised in that the cavity comprises a respective recessed area, in particular created in the front edge of the or each lateral flank of the quick-release fastener such that, when the trunnion is inserted in the receiving cavity or cavities through the upper opening or openings, the trunnion may be inserted in the or each recessed area, preferably over at least half of its transverse cross-section, i.e. over a sector with an angle of at least 180, and, as the driver of the bucket causes the quick-release fastener to turn in the correct direction in relation to the connection device, the pin moves along the lower front wall until the trunnion reaches its position in the or each recessed area of the or each cavity of the or each hook, and, when the trunnion reaches the recessed area, the pin reaches the elbow formed between the upper and lower front walls of the guide section.

13. The device according to claim 3, characterised in that the guide means comprise at least one support pin (800), in particular protruding laterally from at least one lateral flank of the connection device, and at least one associated guide section (810) of the at least one support pin, in particular formed in the quick-release fastener, in particular in a lateral flank (102) of the quick-release fastener, the guide section (810) being open at least towards the bottom and towards the outside of the quick-release fastener, preferably towards the bottom, towards the rear and towards the outside of the quick-release fastener; characterised in that the quick-release fastener comprises at least one coupling hook (7) and the connection device at least one coupling trunnion (5), and the or each hook (7) comprises a part forming a rod and a part forming a coupling head which extends upwards from the end of the part forming a rod to thus define a respective cavity in which a trunnion of the connection device is intended to be inserted via a respective upper opening; and and, when the or each hook is beneath the front trunnion, the or each support pin abuts against the lower front wall, and, as the driver of the bucket causes the quick-release fastener to turn in the correct direction in relation to the connection device, the pin moves along the lower front wall until the trunnion reaches its position in the or each recessed area of the or each cavity of the or each hook.

14. The device according to claim 3, characterised in that the guide means comprise at least one support pin (800), in particular protruding laterally from at least one lateral flank of the connection device, and at least one associated guide section (810) of the at least one support pin, in particular formed in the quick-release fastener, in particular in a lateral flank (102) of the quick-release fastener, the guide section (810) being open at least towards the bottom and towards the outside of the quick-release fastener, preferably towards the bottom, towards the rear and towards the outside of the quick-release fastener; characterised in that the quick-release fastener comprises at least one coupling hook (7) and the connection device at least one coupling trunnion (5), and the or each hook (7) comprises a part forming a rod and a part forming a coupling head which extends upwards from the end of the part forming a rod to thus define a respective cavity in which a trunnion of the connection device is intended to be inserted via a respective upper opening; and characterised in that the cavity comprises a respective recessed area, in particular created in the front edge of the or each lateral flank of the quick-release fastener such that, when the trunnion is inserted in the receiving cavity or cavities through the upper opening or openings, the trunnion may be inserted in the or each recessed area, preferably over at least half of its transverse cross-section, i.e. over a sector with an angle of at least 180, and, when the or each hook is beneath the front trunnion, the or each support pin abuts against the lower front wall, and, as the driver of the bucket causes the quick-release fastener to turn in the correct direction in relation to the connection device, the pin moves along the lower front wall until the trunnion reaches its position in the or each recessed area of the or each cavity of the or each hook.

15. A construction machine comprising a lifting element, in particular a lifting arm, and a tool, in particular a bucket, and a device according claim 1, the coupler or quick-release fastener being attached to the machine and the connection device being attached to the tool.

16. A connection device of a device forming a coupler, in particular according to claim 1, comprising a coupler, or quick-release fastener, which is intended to be attached to a construction machine, such as a mechanical shovel, and the connection device comprising attachment means intended to allow it to be attached to a tool, such as a bucket, and at least one coupling trunnion, or hook respectively, intended to be coupled to at least one associated hook, or trunnion respectively, of the quick-release fastener, is characterised in that it comprises guide means intended to guide the pivoting movement of the quick-release fastener, in particular self-centring means intended to allow relative self-centring of the quick-release fastener and the connection device, for example at least one pin protruding laterally from the inner surface of at least one lateral flank of the connection device, in particular two pins, left and right respectively, protruding laterally from the respective inner surfaces of two left and right lateral flanks of the connection device.

17. A coupler or quick-release fastener of a device forming a coupler, in particular according claim 1, comprising the coupler, or quick-release fastener, which is intended to be attached to a construction machine, such as a mechanical shovel, and a connection device intended to be attached to a tool, such as a bucket, the coupler or quick-release fastener comprising at least one coupling hook, or trunnion respectively, which is intended to be coupled to at least one associated trunnion, or hook respectively, of the connection device, characterised in that it comprises guide means intended to guide the pivoting movement of the connection device, in particular self-centring means intended to allow relative self-centring of the quick-release fastener and the connection device, for example at least one guide section formed in a lateral flank of the quick-release fastener, the guide section being open at least towards the bottom and towards the outside of the quick-release fastener, in particular two guide sections formed in two left and right lateral flanks of the quick-release fastener.

Description

[0019] By way of example only, a preferred embodiment of the invention will now be described with reference to the drawings in which:

[0020] FIG. 1 is a side view showing, on the one hand, the coupler or quick-release fastener and, on the other hand, the bucket to which a connection device has been attached, said device comprising two trunnions, the figure showing the coupler at a distance from the bucket, i.e. in a position in which attachment or coupling has not yet started;

[0021] FIG. 2 is a larger-scale view of part of FIG. 1 showing the hook of the coupler which has been inserted beneath one of the two trunnions of the connection device;

[0022] FIG. 3 is a view that is substantially identical to the view in FIG. 2, in which the hook is attached to the trunnion and the bucket has been raised above the ground;

[0023] FIG. 4 is a view showing the relative position of the coupler and the bucket when the operator has activated the coupler to swing in the wrong direction, i.e. in the figure, pivoting the top part of the coupler with respect to the bottom part in the clockwise direction;

[0024] FIGS. 5 to 7 show the same coupler and bucket from FIGS. 1 to 4, but in a configuration in which the first coupling stage takes place by means of the other of the two trunnions, the coupler being oriented, with respect to the bucket, inverted through 180 compared to FIGS. 1 to 4;

[0025] FIG. 8 shows an identical situation to that shown in FIG. 4 but with the reverse orientation of the quick-release fastener shown in FIGS. 5 to 7;

[0026] FIG. 9 is an exploded perspective view of the various elements forming the quick-release fastener;

[0027] FIG. 10 is a longitudinal sectional view of the quick-release fastener from FIG. 9, showing how the fastener is locked once coupling of the hook to one of the connection device trunnions has been achieved;

[0028] FIG. 11 is a similar view to FIG. 10 in which the second trunnion has penetrated the inside of the quick-release fastener;

[0029] FIG. 12 is a similar view to FIGS. 10 and 11, showing the locked position of the quick-release fastener;

[0030] FIGS. 13 to 16 show the relative positions of the various elements involved in locking the fastener at various moments of the locking action;

[0031] FIG. 17 shows the unlocking wrench and its position in relation to the fastener in order to unlock said fastener;

[0032] FIG. 18 shows the relative position of the lever axle in relation to the oblong opening in which it is able to move in translation when the fastener is in the position shown in FIG. 11;

[0033] FIG. 19 shows the relative position of the lever axle in relation to the oblong opening in which it is able to move in translation when the fastener is in the position shown in FIG. 12;

[0034] FIG. 20 is a side view of the quick release fastener and of the connection device as per an embodiment of the present invention, the right lateral flank of the quick release fastener comprising a guiding cut out formed in the external face of the wall of the lateral flank and intended to cooperate with a support pin projecting from the internal face of the corresponding lateral flank of the connection device, the front hook of the quick release fastener being coupled to the front trunnion of the connection device;

[0035] FIGS. 21 to 23 are figures identical to FIG. 20, but representing the quick release fastener and the connection device in their respective position as their relative rotation occurs in view of arriving to their final position in which these can locked the one to the other;

[0036] FIG. 24 is a perspective view of the connecting device of the embodiment of the coupler forming device of FIGS. 20 to 23, fixated to the bucket; and

[0037] FIG. 25 is a perspective view of the connecting device of the embodiment of the coupler forming device of FIGS. 20 to 23.

[0038] The figures show a quick-release fastener 1 which engages with a connection device 2, which is itself attached to a bucket 3.

[0039] The connection device 2 comprises a base plate from the upper face of which two lateral flanks 4 extend in a perpendicular manner. Two parallel, cylindrical-circular-shaped trunnions, top 5 and bottom 6 respectively (when the bucket is placed on the ground), are attached to the two flanks such as to extend from one to the other at a distance from the base plate to allow two front hooks 7 originating from the quick-release fastener to pass between them and the base plate.

[0040] The quick-release coupler is shown in detail, in an exploded view, in FIG. 9. The only items missing from this figure are the two lateral wings 8 supporting the axles enabling the quick-release fastener 1 to be attached to the arm of the lever of a construction machine such as the arm of a mechanical shovel.

[0041] The quick-release fastener 1 comprises a bottom body comprising an upper base plate 101 and two lower lateral flanks 102 (only one is visible on FIG. 9) originating from the upper plate 101, each flank 102 terminating, on a side subsequently referred to as the front side, in a respective front hook 7.

[0042] A component 103 forming a lever is mounted such that it pivots with respect to an axle 104 parallel to the axle of the trunnions when the quick-release fastener and the connection device are locked together. The axle 104 is connected to the quick-release fastener but is able to undergo a limited movement through the oblong openings 109 formed by the lateral flanks 102.

[0043] Two rollers 120 which are able to roll from one side to the other of the oblong openings 109 are attached by bolts (shown in the figure but not referred to by reference numerals) on each side of the axle 104. However, this attachment does not prevent relative rotation of the rollers around the axle 104, thus allowing the axle 104, and thus also the lever 103, to be driven in translation, even if said lever does not pivot.

[0044] The lever 103 comprises two upper left and right branches 105 and two lower left and right branches 106, which extend backwards from the axle 104. The upper branches extend further backwards than the lower branches. The left upper and lower branches define a left-hand, C-shaped space, the opening of which is turned towards the back and in the same manner, the right upper and lower branches define a right-hand C-shaped space, the opening of which is turned towards the back.

[0045] Two right and left front branches 107 extend forwards from the axle 104. They each consist of a proximal portion 108 followed by a distal portion 111, which extends in an inclined manner in relation to the proximal portion 108, in particular substantially at 90. The two distal portions 111 pass through two through openings 112, left and right respectively, formed through the base plate 101 of the quick-release fastener to emerge from the upper surface of the base plate and are each fixed to a front end of a spring 400, left and right respectively, while the other respective ends of each spring 400 are attached to two left and right studs 113 in the form of hooks originating from the upper face of the base plate 101, substantially in the region of the rear edge of the base plate 101. The springs 400 are tension springs that tend to draw the front ends of the distal portions backwards. Two left and right covers 114 are attached by bolts (shown but not referred to in the figure) against the lateral flanks 102 to conceal and/or protect the openings 109 from the exterior, in particular to prevent earth getting lodged in the oblong openings 109 and impeding movement of the rollers 120.

[0046] A rear plate 500 which substantially takes the shape of a rectangular parallelepiped extends transversely between the two lateral flanks 102, substantially in the region of the rear edge of the base plate 101. The rear plate 500 is attached to the flanks by bolts and holes, shown in FIG. 9 but without reference numerals. A rear notch 501 is formed centrally in the upper edge of the rear plate 500, on the rear side of the plate.

[0047] In longitudinal section, the rear face of the rear plate 500 is substantially rectilinear and vertical. The front face of the rear plate 500 in turn comprises a first substantially vertical lower portion, followed by an upper portion inclined upwards towards the rear.

[0048] A component 502, referred to as a lug, is mounted on the lever 103, between the left and right upper branches 105, being able to pivot with respect to the lever 103, with respect to an axle 503, parallel to the axle 104 and which extends into the space between the two upper branches 105 of the lever 103. The axle 503 of the lug 502 is attached to the lever 103 by means of a support component 504 in the form of a bridge attached to the upper face of the upper branches 105 by corresponding bolts and holes shown on FIG. 9 but not referred to by reference numerals. A torsion spring 505 is attached such that it acts on the lug 502. The lug 502 comprises, on either side of the axle 503, a rear part 506 and a front part 507, the front part 507 having smaller dimensions than the rear part 506, and thus a lower weight, such that the lug tends, under the effect of its own weight, to swing in a direction such as to cause its rear part to fall downwards (anticlockwise direction in the figures). The torsion spring 505 is mounted such as to act on the lug 502 in a manner that also loads the rear part downwards. The rear part 506 comprises an upper protrusion 508 and terminates in a rear tooth 509, which projects towards the bottom of the remainder of the rear part and which has dimensions enabling it to penetrate the rear notch 501 of the plate 500. A groove 510 which is intended to receive the upper protrusion 508 is formed in the lower face of the base plate 101 when the upper branches 105 of the lever 103 are positioned such that they are abutted against the lower face of the base plate 101.

[0049] On the front side, the quick-release fastener 1 defines two respective receiving cavities 200 for one or other of the two trunnions 5 and 6 of the connection device 2. Two receiving cutouts 300 for the other of the two axles 5 and 6 of the connection device are formed in the lateral flanks 102 on the rear side of the plate 101.

[0050] Each hook 7 comprises a part 71 forming a rod that extends at the front end of one of the respective flanks 102, parallel to the plane of the plate 101, and terminates in a part 72 forming a coupling head, which extends upwards from the end of the part 71 forming a rod. Each hook 7 thus defines, with the front edges of the lateral flanks 102, two cavities 200 in which one or other, depending on the direction in which they are inserted in relation to the bucket, of the two axles 5 and 6 originating from the connection device 2 attached to the bucket 3 are intended to be inserted through respective upper openings 201. The cavity 200 comprises a respective recessed area 202 created in the front edge of each lateral flank 102 and with a shape that complements at least half of the circular transverse cross-section of the axles 5 and 6 such that, when the axle 5 or 6 originating from the bucket is inserted in the receiving cavities 200 through the openings 201, the axle can be inserted in the recess 202 over at least half of its transverse cross-section, i.e. over a sector with an angle of at least 180.

[0051] In relation to the lower, or bottom, surface 210 of each cavity 200, the uppermost end 203 of the part 72 forming the head extends in the vertical direction at least in the region of the centre of the cross-section of the axle 5 or 6 when this is located in the cavity 200, in particular above the centre, and in particular substantially in the region of the diameter, or even above the diameter. Similarly, the uppermost end 204 of the surface of the part forming the head of the side of the cavity 200 extends above the centre of the axle 5 or 6, in particular at a height between the radius and the diameter, or could even extend substantially to a height equal to the diameter of the axle.

[0052] The respective dimensions of the axles of the trunnions of the connection device attached to the bucket and the cavities 200 formed by the hooks 7 are selected such that once the head 72 part has been inserted beneath the axle 5 or 6 of the bucket, as shown on FIG. 4 for example, and the operator of the lifting machine causes the coupler to turn in the wrong direction, i.e. in the clockwise direction in FIGS. 1 to 4, the shoulder formed between the edge 205 of the opening 201 and the upper edge 206 of the plate 101 of the quick-release fastener 1 will abut against the edges of the flanks 4 of the connection device originating from the bucket 3 such that even though the operator has started to raise the bucket away from the ground, the quick-release fastener and the connection device can no longer pivot in relation to one another, the top part of the hook thus still remaining beneath the axle and preventing this axle, and thus also the bucket, from falling back to the ground, the stop in the region of the shoulder preventing any sudden withdrawal of the axle from the cavities 200. This stop comes into play beyond a rotation in the wrong direction of approximately 15.

[0053] If the bucket operator causes the quick-release fastener to turn in the right direction (in the anticlockwise direction in FIGS. 1 to 4) to lock the coupler to the connection device of the bucket, the cutouts 300 cover the other axle 5 of the bucket from above.

[0054] As the operator causes the quick-release fastener to pivot to insert the second axle 5 in the cutouts 300, the second axle 5 of the bucket comes to bear against the upper branches 105 of the lever 103, causing said lever to pivot and retreat (towards the front). At the limit of travel, the upper faces of the two upper branches 105 are parallel with the lower face of the base plate 101 and, at the same time, the lug 502, which is mounted such that it pivots in relation to the lever 103 is pushed by the springs 400 towards the rear such that its tooth 509 passes over the upper edge of the rear plate 500 and penetrates the notch 501.

[0055] This backwards movement, under the effect of the springs 400, also drives the rear lower branches of the lever, which thus pass beneath the trunnion, trapping it in the cavity 300.

[0056] Thus, as shown on FIGS. 12 and 16, the quick-release fastener is locked to the bucket. This is a well secured locking mechanism, and, in particular, even if one or more springs 400 were to break or become detached, the quick-release fastener of the bucket would not become unlocked, thus being held in a secure manner.

[0057] The tooth 509 has a rear surface that is inclined upwards and backwards such that when the springs 400 push the lever 103 backwards again once this is in position with the rear upper branches in the horizontal direction, the pushing force, in conjunction with the inclined shape of the rear face of the tooth, causes the lug to pivot away from the torsion spring and allows the tooth 509 to pass into the notch 501.

[0058] FIG. 17 shows a wrench 600 enabling the fastener to be unlocked once said fastener has been locked, i.e. once the tooth 509 has swung into the notch 501 of the plate 500.

[0059] The wrench comprises an extended handle 601 (only part of said handle is shown in the figure) terminating in a head part comprising two upper 603 and lower 604 lateral arms and a central projection 605. A stud 606 extends transversely from the end of the upper arm 603, in a direction perpendicular to the handle such that it can penetrate an eyelet formed in a stud 700 originating from the upper face of the plate 101 of the fastener. A nose 609 originates from the lower lateral arm, said nose extending towards the upper arm.

[0060] In order to unlock the fastener, the user inserts the stud 606 in the eyelet and causes the end of the nose 609 to move against the rear face of the protrusion 508 of the tooth 502, the dimensions of the nose 609 being such that it can penetrate the groove 511 in which the protrusion 508 is received, then exerts a rotation movement such that the proximal end of the handle (the opposite end to the head) is moved downwards, which has the effect of causing the lug to pivot away from the torsion spring 605 and causing the tooth 509 to come out of the notch 501, thus unlocking the quick-release fastener.

[0061] As shown in FIGS. 20 to 23, when the hooks 7 come below the front trunnion 5 by their ends 204, each support pin 800 comes in abutment against the lower front wall 816 (FIG. 20). As the controller of the bucket makes the quick release fastener to rotate in the correct direction in relation to the connection device, the pin 800 moves along the wall 816 up to the point when the trunnion 5 reaches its position in the recessed area 202 of the cavities 200 of the hooks 7, as shown in FIG. 22. The pin 800 is then positioned at the entrance of the upper region 812 and passes therefore over the elbow 818, in contact with lower front wall 815. As the rotation keeps going on, pin 800 reaches the top wall 814. In this final position, the quick release fastener and the connection device can then be mutually locked.

[0062] The quick release fastener of FIGS. 20 to 23 and 25 is identical to the one of FIGS. 1 to 19, except that two left and right guiding cut-outs are formed in the external surfaces of the left and right lateral flanks, the right guiding cut-out 810 being visible in FIGS. 20 to 23, while the left guiding cut-out 810 is visible in FIG. 25.

[0063] in FIGS. 20 to 25, the right lateral flank 102 comprises a right guiding cut-out 810 formed in the external wall of the lateral flank. The left lateral flank, visible in FIG. 25, comprises a same guiding cut-out formed in its external wall. Guiding cut-out 810 is open toward the bottom, towards the outside and towards the rear and comprises a lower region 811, the longitudinal dimension of length of which, that is in the front-rear direction of the quick release fastener, narrows toward the top, followed by an upper region 812, the length dimension of which is substantially constant up to the top.

[0064] Thus, as seen in longitudinal cross section, cut out 810 comprises a longitudinal top forming wall 814, substantially horizontal, followed by a upper front wall 815, substantially vertical, followed by a lower front wall 816 which extends up to the lower opening of the cut out 810, being inclined in respect of the upper front wall 815, notably of an angle of around 45, so as to form an elbow 818.

[0065] A right support pin 800 projects toward the inside of the right lateral flank 4 of the connection device 2 and is intended to cooperate with the right cut out 810. A left support pin 800, identical to the right support pin, projects from the left lateral flank 4 and is intended to cooperate with the left cut out.

[0066] As shown in FIGS. 20 to 23, when the hooks 7 come below the front trunnion 5 by their ends 204, each support pin 800 comes in abutment against the lower front wall 816 (FIG. 20). As the controller of the bucket makes the quick release fastener to rotate in the correct direction in relation to the connection device, the pin 800 moves along the wall 816 up to the point when the trunnion 5 reaches its position in the recessed area 202 of the cavities 200 of the hooks 7, as shown in FIG. 22. The pin 800 is then positioned at the entrance of the upper region 812 and passes therefore over the elbow 818, in contact with lower front wall 815. As the rotation keeps going on, pin 800 reaches the top wall 814. In this final position, the quick release fastener and the connection device can then be mutually locked.

[0067] In FIGS. 20 to 23, only pin 800 is shown, the right lateral flank having been omitted for sake of clarity concerning the interaction between the pin and the quick release fastener.

[0068] In this description, the vertical direction is defined as being perpendicular to the plane of the upper face of the base plate 101 of the quick-release fastener, the top side being the side towards which the opening of the cavity 200 is turned. The terms proximal and distal are defined in relation to the centre of the quick-release fastener.

[0069] In particular, the terms top and bottom and lower and upper are defined in relation to this vertical direction, the connection device, which is attached to the bucket, being located beneath the quick-release fastener in the locked position.

[0070] In this application, an embodiment in which the pin, or pins, originates or originate from the flanks of the connector or connection device is described by way of example, while the guide section or sections are formed in the quick-release fastener. However, without departing from the scope of the present invention, the reverse arrangement is also possible, i.e. the pin or pins originating from the quick-release fastener and the section or sections being formed in the connector. It is also conceivable that one pin or pins could originate from the quick-release fastener and another or other pins from the connector, while the corresponding sections are formed both in the quick-release fastener and the connector.