high security quick release

Abstract

Title: High-security quick-release coupling Device forming a coupler comprising a coupler (1), or quick-release coupling, intended to be secured to an arm of a public works machine, and a connection device (2), intended to be secured to a tool such as a bucket; the connection device comprising at least one trunnion (5; 6; 5, 6), preferably two trunnions (5, 6) respectively front and rear;the coupler comprising a base body from which at least one hook originates on a front side, the or each hook (7) comprising a rod region and a hook head region (72) which extends upwards from the rod region to form, with the base body, at least one cavity (200) for receiving the pin or one of the pins having an opening on the top which extends between the base body and the respective head region of the respective hook: characterized in that when the pin or one of the pins is located inside the receiving cavity in contact with the rod region, the head region projects upwards from the center of the circular section of the pin Figure for abstract: Fig. 11;

Description

Title of the invention: High-security quick-release fastener

[0001] The present invention relates to a public works machine, for example an excavator, to which a tool, such as a bucket, is removably attached by means of a quick coupler device consisting of a coupler, also called a quick coupler, secured to the machine, in particular to an arm of the machine, and a connection device secured to the tool to cooperate with the coupler. The present invention also relates to a quick coupler device of this type as well as to a quick coupler or coupler of this type.

[0002] Hereinafter, we will speak of a bucket. However, the term "bucket" must be understood as also encompassing any other tool or equipment intended to be mounted on a public works machine by means of the quick coupler and the connection device.

[0003] In the prior art, so-called reversible quick couplers are already known, i.e. which allow attachment to the bucket, and in particular to the connection device secured to the bucket, by presenting the coupler or quick coupler in two possible orientations relative to the bucket, the quick coupler being rotated 180° to move from one orientation to the other.

[0004] Conventionally, the connection device intended to be secured to the bucket comprises a cradle-shaped element having a base element and two left and right lateral flanks between which extend, at a distance from each other, two parallel cylindrical circular trunnions or axes, arranged so as to be able to each cooperate with at least one front hook, in particular two left and right front hooks, coming from the coupler for the coupling between the coupler or quick coupler and the connection device, to thus achieve the coupling of the bucket to the arm of the public works machine.

[0005] In these reversible devices known from the prior art, the or each front hook comprises a rod portion and a hook head portion which extends laterally from the rod portion to define a cavity for receiving one of the pins, the cavity being open at the top to allow the pin to enter or exit the cavity or out of it.

[0006] These prior art couplers are dangerous to use. In particular, it can frequently happen during the hooking step that the bucket falls back from its hooking with the hook(s) before the attachment of the coupler to the bucket has been fully secured, which, on construction sites where there are people, can prove extremely dangerous.

[0007] The present invention aims to overcome the drawbacks of the prior art by proposing a device forming a coupler, in particular a so-called reversible device, as well as a coupler or quick attachment to be used in a device of this type, which is safer to use.

[0008] According to the invention, a device forming a coupler comprising a coupler, or quick coupler, intended to be secured to a public works machine, such as an excavator, and a connection device, intended to be secured to a tool, such as a bucket, the connection device comprising at least one trunnion, preferably two trunnions, in particular parallel to each other;the coupler comprising a base body from which at least one front hook originates on a front side, the or each front hook having a shank portion and a hook head portion, which extends upwardly from the shank portion to define at least one receiving cavity for the pin or one of the pins having an opening on the top which extends between the base body and the respective head region of the respective hook, is characterized in that when the pin or one of the pins is in the or one receiving cavity in contact with the shank portion, the head portion extends upwardly beyond the center of the circular section of the pin. ;

[0009] Preferably, the head portion extends upwardly beyond the journal.

[0010] Preferably, the or each receiving cavity comprises, on the rear side, a recess hollowed out in the base body into which the journal can penetrate at least partially.

[0011] Preferably, the recess has a shape, in longitudinal section, complementary to substantially at least half of the circular section of the journal.

[0012] By thus providing at least one front hook having a hook head which extends, relative to the trunnion, higher than in the prior art, it is ensured that, when the or each front hook is hooked to the trunnion and the operator of the machine lifts the bucket away from the ground in order to lock the quick coupler to the connection device, if the operator makes a false maneuver and pivots the coupler in the wrong direction, the trunnion does not come out of its cooperation with the or each hook, and the bucket is thus prevented from falling back to the ground.

[0013] Furthermore, by providing the recess, in particular at least semi-circular, it is ensured that even if the driver continues to rotate in the wrong direction, the upper edge of the recess will come into abutment against the edges of the sides of the connection device and prevent any further rotation of the coupler relative to the bucket and thus prevent the bucket from becoming detached from the coupler once the or each hook is engaged with the journal. This provides a device forming a coupler that is particularly safe to use.

[0014] Thus, preferably, the connection device comprises a lower base plate and on the upper side two lateral flanks, two pins at a distance from each other, being fixed to the two flanks so as to extend between them, at a distance from the base plate, to allow the passage between them and the base plate of the or each front hook of the quick attachment.

[0015] Preferably, the coupler, or quick coupler, comprises an upper base plate from which two lateral flanks project downwards, each flank terminating on the front side with a respective hook.

[0016] Preferably, in longitudinal section, the highest point of the head portion of the hook is located beyond the pin, when the latter is arranged in the cavity, in contact with the rod portion.

[0017] Preferably, in longitudinal section, the highest point of the inner wall of the part of the cavity formed by the part forming the head of the hook is located beyond the center of the section of the journal, and in particular substantially at a height between the radius and the diameter of the section of the journal, in particular equal to the diameter of the section of the journal.

[0018] The present invention also relates to a quick fastener intended to form part of a device according to the invention.

[0019] Preferably, the connection device comprises two pins and there is defined, in the base body of the coupler, at least one second rear pin-receiving cavity intended to receive the other pin, once the first pin is hooked to the hook or to each hook, this second rear cavity being open downwards, that is to say opposite to the direction towards which the opening of the first front receiving cavity is turned.

[0020] The present invention also relates to a public works machine comprising a lifting element, in particular a lifting arm, and a tool, in particular a bucket, and a device forming a quick coupler according to the invention, the coupler or quick attachment being fixed to the lifting element of the machine, while the connection device is fixed to the tool.

[0021] By way of example only, a preferred embodiment of the invention will now be described with reference to the drawings, in which:

[0022] [Fig. 1] is a side view showing, on the one hand, the coupler or quick coupler and, on the other hand, the bucket to which a connection device comprising two pins has been fixed, the figure showing the coupler at a distance from the bucket, that is to say in a position in which the attachment or coupling has not yet begun;

[0023] [Fig.2] is an enlarged view of part of [Fig.l] showing the coupler hook which has been inserted under one of the two journals of the connection device;

[0024] [Fig. 3] is a view substantially identical to that of [Fig. 2] in which the hook has been hooked onto the trunnion and the bucket has been lifted clear of the ground;

[0025] [Fig.4] is a view showing the relative position of the coupler and the bucket when the driver has actuated the tilting of the coupler in the wrong direction, i.e. a pivoting in the figure of the upper part of the coupler relative to the lower part, in a clockwise direction;

[0026] Figures 5 to 7 show the same coupler and bucket of Figures 1 to 4, but in a configuration in which the first stage of the coupling is carried out via the other of the two journals, the coupler being oriented, relative to the bucket, inverted at 180° with respect to Figures 1 to 4;

[0027] [Fig.8] represents a situation identical to that of [Fig.4], but with the reversed orientation of the quick release of figures 5 to 7;

[0028] [Fig.9] is an exploded perspective view of the various elements constituting the quick coupler;

[0029] [Fig. 10] is a longitudinal sectional view of the quick coupling of [Fig. 9], showing how the coupling is locked after the hook has been attached to one of the journals of the connection device;

[0030] [Fig. 11] is a view similar to [Fig. 10], in which the second pin has penetrated inside the quick coupler;

[0031] [Fig. 12] is a view similar to Figures 10 and 11, showing the locked position of the quick coupler;

[0032] Figures 13 to 16 show the relative positions of the various elements involved in locking the fastener, at different times during the locking action;

[0033] [Fig. 17] shows the unlocking key and its positioning relative to the fastener for unlocking;

[0034] [Fig. 18] shows the relative position of the lever axis with respect to the oblong opening in which it can move in translation when the attachment is in the position of [Fig.l 1]; and

[0035] [Fig. 19] shows the relative position of the lever axis with respect to the oblong opening in which it can move in translation when the attachment is in the position of [Fig. 12].

[0036] The figures show a quick coupling 1 which cooperates with a connection device 2, itself secured to a bucket 3.

[0037] The connection device 2 comprises a base plate from the upper face of which two lateral flanks 4 extend perpendicularly. Two journals respectively 5 top and 6 bottom (when the bucket is placed on the ground), parallel and of circular cylindrical shape, are fixed to the two flanks so as to extend from one to the other, at a distance from the base plate, to allow the passage between them and the base plate of two front hooks 7 from the quick attachment.

[0038] The quick coupler is shown in detail, in an exploded view, in [Fig. 9]. Only the two lateral wings 8 which support axes allowing the quick coupler 1 to be fixed to the lever arm of a public works machine, such as the arm of an excavator, are missing from this figure.

[0039] The quick attachment 1 comprises a base body comprising an upper base plate 101 and two lower lateral flanks 102 (only one is visible in [Fig.9]) originating from the upper plate 101, each flank 102 ending, on a side designated hereinafter as being the front side, by a respective front hook 7.

[0040] A lever-forming part 103 is pivotally mounted relative to an axis 104 parallel to the axis of the journals when the quick coupler and the connection device are locked together. The axis 104 is connected to the quick coupler while being able to undergo a limited movement by oblong openings 109 formed in the lateral flanks 102.

[0041] Two rollers 120 capable of rolling from one side to the other of the oblong openings 109 are fixed by screws (shown in the figure but not designated by numerical references) on each side of the axis 104. However, this fixing does not prevent a relative rotation of the rollers around the axis 104, thus allowing the translational drive of the axis 104, and therefore also of the lever 103, even when the latter does not pivot.

[0042] The lever 103 has two upper left and right branches 105 and two lower left and right branches 106 which extend rearwardly from the axis 104. The upper branches extend further rearwardly than the lower branches. The upper and lower left branches define a left C-shaped space whose opening faces rearward and similarly, the upper and lower right branches define a right C-shaped space whose opening faces rearward.

[0043] Two front right and left branches 107 extend forward from the axis 104. They are each made up of a proximal section 108 continued by a distal section 111, which extends inclined relative to the proximal section 108, in particular at substantially 90°. The two distal sections 111 pass through two through openings 112 respectively left and right formed through the base plate 101 of the quick coupler to emerge from the upper surface of the base plate and are each fixed to a front end of a spring 400 respectively left and right while the other respective ends of each spring 400 are fixed to two left and right hook-shaped studs 113 coming from the upper face of the base plate 101, substantially at the rear edge of the base plate 101. The springs 400 are compression springs tending to pull the front ends of the distal sections rearward. Two left and right covers 114 are fixed by screws (shown but not referenced in the figure) against the lateral flanks 102 to hide and / or protect the openings 109 from the outside, in particular to prevent earth from becoming lodged in the oblong openings 109 and hindering the movement of the rollers 120.

[0044] A rear plate 500 of substantially rectangular parallelepiped shape extends transversely between the two lateral flanks 102, substantially at the rear edge of the base plate 101. The rear plate 500 is fixed to the flanks by screws and holes, shown in [Fig.9] but without numerical references. A rear notch 501 is formed centrally in the upper edge of the rear plate 500, on the rear side of the plate.

[0045] In longitudinal section, the rear face of the rear plate 500 is substantially rectilinear and vertical. The front face of the rear plate 500 comprises a first substantially vertical lower section, followed by an upper section inclined upwards towards the rear.

[0046] A part 502, called a lug, is mounted on the lever 103, between the two upper branches 105 left and right, being pivotable relative to the lever 103, relative to an axis 503, parallel to the axis 104 and which extends in the space between the two upper branches 105 of the lever 103. The fixing of the axis 503 of the lug 502 to the lever 103 is carried out by means of a bridge-shaped support part 504 fixed to the upper face of the upper branches 105 by screws and corresponding holes shown in [Fig.9] but not designated by numerical references. A torsion spring 505 is mounted so as to act on the lug 502.The lug 502 comprises, on either side of the axis 503, a rear part 506 and a front part 507, the front part 507 being smaller than the rear part 506, and therefore of lesser weight, so that the lug has a tendency, under the effect of its weight, to tilt in the direction tending to cause its rear part to fall downwards (counterclockwise in the figures). The torsion spring 505 is mounted to act on the lug 502 so as also to urge the rear part downwards. The rear part 506 has an upper boss 508 and ends with a rear tooth 509 which projects downwards from the rest of the rear part and which has dimensions allowing it to penetrate into the rear notch 501 of the plate 500.A groove 510 is formed in the lower face of the base plate 101 for receiving the upper boss 508 when the upper branches 105 of the lever 103 are positioned in abutment against the lower face of the base plate 101.

[0047] The quick attachment 1 defines, on the front side, two respective cavities 200 for receiving one or the other of the two pins 5 and 6 of the connection device 2. On the rear side of the plate 101, two cutouts 300 are formed in the lateral flanks 102 for receiving the other of the two axes 5 and 6 of the connection device.

[0048] Each hook 7 comprises a rod-forming portion 71 which extends at the front end of one of the respective flanks 102, parallel to the plane of the plate 101, and which ends with a hooking head-forming portion 72 which extends upwards from the end of the rod-forming portion 71. Each hook 7 thus defines, with the front edges of the lateral flanks 102, two cavities 200 into which are intended to be inserted, through respective upper openings 201, one or the other, depending on the direction of insertion relative to the bucket, of the two axes 5 and 6 coming from the connection device 2 fixed to the bucket 3.The cavity 200 comprises a respective recessed area 202, hollowed out in the front edge of each lateral flank 102 and of complementary shape to at least half of the circular cross-section of the axes 5 and 6, so that when the axis 5 or 6 coming from the bucket is inserted into the receiving cavities 200 through the openings 201, the axis can be inserted into the recess 202 over at least half of its cross-section, that is to say over an angle sector of at least 180°.

[0049] With respect to the lower or bottom surface 210 of each cavity 200, the uppermost end 203 of the head-forming portion 72 extends, in the vertical direction at least at the center of the section of the axis 5 or 6, when the latter is located in the cavity 200, in particular beyond the center, and in particular substantially at the diameter, or even beyond the diameter. Similarly, the uppermost end 204 of the surface of the head-forming portion on the side of the cavity 200 extends beyond the center of the axis 5 or 6, in particular at a height between the radius and the diameter, or even could extend substantially to a height equal to the diameter of the axis.

[0050] The dimensions respectively of the axes of the journals of the connection device fixed to the bucket and of the cavities 200 formed by the hooks 7 are chosen so that once the head part 72 has been inserted under the axis 5 or 6 of the bucket, as shown for example in [Fig.4], and the driver of the lifting device turns the coupler in the wrong direction, i.e. clockwise in Figures 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 coupler 1 comes into abutment against the edges of the sides 4 of the connection device coming from the bucket 3, so that although the driver has started to lift the bucket away from the ground, the quick coupler and the connection device can no longer pivot relative to each other, the head part of the hook thus always remaining under the axis and preventing it, and therefore also the bucket, from falling back to the ground, the stop at the shoulder preventing any untimely exit of the axis from the cavities 200. This stop occurs from a rotation in the wrong direction of approximately 15°.

[0051] When the bucket driver rotates the quick coupler in the correct direction (counterclockwise in Figures 1 to 4) to lock the coupler to the bucket connection device, the cutouts 300 cover the other axle 5 of the bucket from above.

[0052] As the driver pivots the quick coupler to insert the second pin 5 into the cutouts 300, the second pin 5 of the bucket comes to bear against the upper branches 105 of the lever 103, causing the latter to pivot and move backward (forward). At the end of the stroke, the upper faces of the two upper branches 105 are parallel to the lower face of the base plate 101, and at the same time, the lug 502, pivotally mounted relative to the lever 103, is pushed by the springs 400 towards the rear so that its tooth 509 passes beyond the upper edge of the rear plate 500 and enters the notch 501.

[0053] This rearward movement, under the effect of the springs 400, also drives the lower rear branches of the lever which thus pass under the journal to trap it in the cavity 300.

[0054] Thus, as shown in Figures 12 and 16, the quick coupler is locked to the bucket. The locking is well secured, and in particular, even if one or more springs 400 break or become detached, there will be no unlocking of the quick coupler from the bucket, which is therefore held securely.

[0055] The tooth 509 has a rear surface which is inclined upwardly and rearwardly so that when the springs 400 push the lever 103 rearwardly once it is in position with the rear upper legs horizontal, the pushing force, in conjunction with the inclined shape of the rear face of the tooth, pivots the lug against the torsion spring and allows the tooth 509 to pass into the notch 501.

[0056] In [Fig. 17], a key 600 is shown for unlocking the fastener once it has been locked, that is to say once the tooth 509 has tilted into the notch 501 of the plate 500.

[0057] The key comprises an elongated handle 601 (only a part is shown in the figure) terminated by a head part comprising two upper lateral arms 603 and lower 604 and a central protrusion 605. A stud 606 extends transversely from the end of the upper arm 603, in a direction perpendicular to the handle, so as to be able to penetrate into an eyelet formed in a stud 700 originating from the upper face of the plate 101 of the fastener. From the lower lateral arm, a nose 609 originates which extends towards the upper arm.

[0058] To unlock the fastener, the user inserts the stud 606 into the eyelet and brings the end of the nose 609 against the rear face of the boss 508 of the tooth 502, the dimensions of the nose 609 being suitable for penetrating into the groove 511 in which the boss 508 is received, then exerts a rotational movement so as to drive the proximal end of the handle (end opposite the head) downwards, which has the effect of pivoting the lug against the torsion spring 605 and causing the tooth 509 to come out of the notch 501, thus unlocking the quick release.

[0059] In the present description, the vertical is defined as being perpendicular to the plane of the upper face of the base plate 101 of the quick coupler, the upper side being the side towards which the opening of the cavity 200 is turned. The terms proximal and distal are defined relative to the middle of the quick coupler.

[0060] In particular, the terms top and bottom and bottom and top are defined relative to this vertical, the connection device, fixed to the bucket, being located under the quick coupler, in the locked position.

Claims

Claims

1. Coupler device comprising a coupler (1), or quick coupler, intended to be secured to a public works machine, such as an excavator, and a connection device (2), intended to be secured to a tool such as a bucket; the connection device comprising at least one journal (5; 6; 5, 6), preferably two journals (5, 6);the coupler comprising a base body from which at least one hook originates on a front side, the or each hook (7) comprising a rod portion and a hook head portion (72) which extends upwards from the rod portion to define at least one cavity (200) for receiving the pin or one of the pins having an opening (201) on the top which extends between the base body and the respective head portion of the respective hook: characterized in that, when the pin or one of the pins is in the receiving cavity in contact with the rod portion, the head portion extends upwards beyond the center of the circular section of the pin.;

2. Device according to claim 1, characterized in that the head portion extends upwardly beyond the journal.

3. Device according to claim 1 or 2, characterized in that the or each receiving cavity has, on the rear side, a recess hollowed out in the base body into which the pin can penetrate at least partially.

4. Device according to claim 3, characterized in that the recess has a shape, in longitudinal section, complementary to substantially at least half of the circular section of the journal.

5. Device according to one of the preceding claims, characterized in that the connection device (2) comprises a lower base plate and on the upper side two lateral flanks, two pins at a distance from each other, being fixed to the two flanks so as to extend between them, at a distance from the base plate, to allow the passage between them and the base plate of the or each front hook of the quick attachment.

6. Device according to one of the preceding claims, characterized in that the coupler (1), or quick coupler, comprises an upper base plate (101) from which two lateral flanks (102) project downwards, each flank (102) ending on the front side with a respective hook (7).

7. Device according to one of the preceding claims, characterized in that, in longitudinal section, the highest point of the head-forming part of the hook is located beyond the pin, when the latter is arranged in the cavity, in contact with the rod-forming part.

8. Device according to one of the preceding claims, characterized in that, in longitudinal section, the highest point of the inner wall of the part of the cavity formed by the part forming the head of the hook is located beyond the center of the section of the pin, and in particular substantially at a height between the radius and the diameter of the section of the pin.

9. Device according to one of the preceding claims, characterized in that the connection device comprises two pins and there is defined, in the basic body of the coupler, at least one second rear pin-receiving cavity intended to receive the other pin, once the first pin is attached to the hook or to each hook, this second rear cavity being open downwards, that is to say opposite to the direction towards which the opening of the first front receiving cavity is turned.

10. Quick fastener intended to form part of a device according to one of the preceding claims.

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