Quick coupler for construction machines

Abstract

Coupler device comprising a coupler, or quick coupler, intended to be secured to a public works machine, such as an excavator, a connection device, intended to be secured to a tool, such as a bucket, coupling means intended to couple the quick coupler to the connection device and locking means intended to lock the coupling; the connection device comprising at least one journal, preferably two journals, in particular parallel to each other;the coupler comprising a base body in which is defined a rear receiving cavity of the or one of the journals, characterized in that it comprises a lever pivotally mounted between a closed position in which it holds the journal or one of the journals in the rear receiving cavity and an open position in which it does not hold the journal, the locking means being arranged to block or prevent rotation of the lever in the closed position.;

Description

[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 refer to 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] 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 at least one trunnion extends, in particular, in the case of so-called reversible devices, two parallel cylindrical circular trunnions or axes, the trunnion or each trunnion being arranged so as to be able to cooperate each with a respective hook from the coupler for the coupling between the coupler or quick coupler and the connection device, thus to couple the bucket to the arm of the public works machine.

[0004] Couplers of this kind are known from US 2012 / 114413 A1, US 6 254 331 B1, FR 2 417 617 A1 and DE 297 08 672 U1. From US 2016 / 289914 A1 a device is known according to the preamble of claim 1.

[0005] 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 coupler, as well as a coupler or quick attachment to be used in a device of this type, which are safer to use.

[0006] 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, a connection device, intended to be secured to a tool, such as a bucket, coupling means intended to couple the quick coupler to the connection device and locking means intended to lock the coupling; the connection device comprising at least one trunnion, preferably two trunnions, in particular parallel to each other;the coupler comprising a base body in which is defined a rear receiving cavity of the or one of the journals, is characterized in that it comprises a lever pivotally mounted between a closed position in which it holds the journal or one of the journals in the rear receiving cavity and an open position in which it does not hold the journal, the locking means being arranged to block or prevent rotation of the lever in the closed position, the lever being mounted movable in translation, in particular in the horizontal direction from the front side to the rear side, the locking means being arranged so as to push the lever in a translational movement to put it in the closed position, in particular in the blocked state.;

[0007] In particular, the axis of rotation of the lever is received in at least one oblong through window, in particular two through windows formed in respective lateral flanks of the base body.

[0008] Preferably, the locking means comprise at least one spring, in particular two springs, which is / are fixed on the one hand to the body of the coupler, in particular a rear part of the body of the coupler, and on the other hand to a front end part of the lever.

[0009] Preferably, in the closed position of the lever, in particular in the locked state, the or each spring extends in the horizontal direction.

[0010] In particular, the or each spring is a tension spring tending to pull the lever backward.

[0011] Preferably, the lever comprises at least one upper branch, in particular two upper left and right lateral branches, and at least one lower branch, in particular two lower left and right lateral branches, which extend rearward from the axis of the lever, the or each upper branch extending further rearward than the or each lower branch, each pair of lower and upper branches, respectively left and right, defining a respective C-shaped cavity, in particular with an opening facing rearward, in which the journal is received in the closed position.

[0012] In particular, the lever comprises at least one front branch, in particular two right and left front branches, extending forward from the axis of the lever, the or each front branch consisting of a proximal section continued by a distal section, which extends inclined relative to the proximal section.

[0013] Preferably, the or each front branch passes through a respective through opening, in particular two respective left and right openings, of the base body to emerge from the upper surface of the base body, the or each front end of the or each distal section being fixed to a front end of a respective spring while the other end of the or each spring is fixed to a respective stud originating from the upper face of the base body, in particular substantially at the upper rear edge of the base body.

[0014] Preferably, the locking means comprise a lug mounted at an upper rear end of the lever, in particular pivoting relative to the latter, in particular at the rear end of the upper rear branch or the rear ends of the upper rear branches.

[0015] In particular, the lug comprises, on either side of its pivot axis, a rear part and a front part, the front part being smaller than the rear part, and therefore of lesser weight, so that the lug tends, under the effect of its weight, to tilt in the direction tending to cause its rear part to fall downwards.

[0016] In particular, the attachment of the pin axis to the lever is carried out by means of a bridge-shaped support piece attached to the two upper faces of two rear upper branches of the lever.

[0017] Preferably, a torsion spring is mounted so as to act on the lug, in particular so as to force the rear part downwards.

[0018] Preferably the rear portion has an upper hump.

[0019] Preferably, the locking means comprise a rear plate forming a stop mounted at a rear end of the coupler, so that, in the locked closed position of the lever, a portion of the lever abuts against the rear plate and is thus prevented from moving forward.

[0020] Preferably, a tooth projects downwardly from the rear portion of the lever, in particular the lug, a notch being formed in the upper edge of the rear plate, on the rear side of the plate, and in the locked closed position, the tooth is received in the notch.

[0021] Preferably, the rear receiving cavity is open downwards.

[0022] Preferably, the connecting 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.

[0023] Preferably, the coupling means comprise at least one front hook, in particular two left and right lateral front hooks, projecting from the front of the base body and the connection device comprises two pins, one intended to be received in the rear receiving cavity and the other in a front receiving cavity or cavities defined by the front hook or hooks.

[0024] Preferably, the coupler, or quick coupler, comprises a base plate from which two lateral flanks project downwards, each flank terminating on the front side with a respective hook.

[0025] 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.

[0026] By way of example only, a preferred embodiment of the invention will now be described with reference to the drawings, in which: There figure 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 started; The figure 2 is a larger scale view of part of the figure 1showing the coupler hook which has been inserted under one of the two pins of the connection device; The figure 3 is a view substantially identical to that of the figure 2 in which the hook hooked onto the trunnion and the bucket was lifted clear of the ground; The figure 4 is a view showing the relative position of the coupler and bucket when the driver has actuated the coupler tilt 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; The figures 5 to 7 represent the same coupler and bucket of the 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° relative to the figures 1 to 4 ; There figure 8 represents a situation identical to that of the figure 4, but with the reverse orientation of the quick release figures 5 to 7 ; There figure 9 is an exploded perspective view of the various elements making up the quick coupler; The figure 10 is a longitudinal sectional view of the quick coupler of the figure 9 , showing how the attachment is locked after the hook has been attached to one of the pins of the connection device; The figure 11 is a view similar to the figure 10 , in which the second pin has penetrated inside the quick coupler; The figure 12 is a view similar to the Figures 10 and 11 , showing the locked position of the quick release; The figures 13 to 16 show the relative positions of the various elements involved in locking the fastener, at different times during the locking action; The figure 17 represents the unlocking key and its positioning relative to the fastener for unlocking; The figure 18 shows the relative position of the lever axis to the oblong opening in which it can move in translation when the clip is in the position of the figure 11 ; and The figure 19 shows the relative position of the lever axis to the oblong opening in which it can move in translation when the clip is in the position of the figure 12 .

[0027] The figures show a quick coupling 1 which cooperates with a connection device 2, itself secured to a bucket 3.

[0028] 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 coming from the quick coupler.

[0029] The quick coupler is shown in detail, in an exploded view, at figure 9 . Only the two lateral wings 8 which support axes allowing the quick coupling 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.

[0030] The quick coupler 1 comprises a base body comprising an upper base plate 101 and two lower side flanks 102 (only one is visible at the figure 9) coming from the upper plate 101, each side 102 ending, on a side subsequently designated as the front side, with a respective front hook 7.

[0031] 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 connecting device are locked together. The axis 104 is connected to the quick coupler but can however undergo a limited movement by oblong openings 109 formed in the lateral flanks 102.

[0032] 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.

[0033] The lever 103 has two upper left and right arms 105 and two lower left and right arms 106 that extend rearwardly from the axis 104. The upper arms extend further rearwardly than the lower arms. The upper and lower left arms define a left C-shaped space with its opening facing rearward and similarly, the upper and lower right arms define a right C-shaped space with its opening facing rearward.

[0034] Two front right and left branches 107 extend forward from the axis 104. They each consist 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 400 springs are tension 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 sides 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.

[0035] A rear plate 500 of substantially rectangular parallelepiped shape extends transversely between the two lateral flanks 102, substantially at the level of the rear edge of the base plate 101. The rear plate 500 is fixed to the flanks by screws and holes, shown in figure 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.

[0036] In longitudinal section, the rear face of the rear plate 500 is substantially straight 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.

[0037] 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 support part 504 in the form of a bridge fixed to the upper face of the upper branches 105 by screws and corresponding holes shown in FIG. figure 9but 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 portion 506 has an upper boss 508 and terminates in a rear tooth 509 which projects downwardly from the remainder of the rear portion and is sized to fit 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.

[0038] 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 pins 5 and 6 of the connection device.

[0039] 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 in which 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, are intended to be inserted, via respective upper openings 201.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°.

[0040] 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.

[0041] 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 figure 4, and the operator of the lifting device turns the coupler in the wrong direction, i.e. clockwise at the 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 abuts 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°.

[0042] When the bucket operator rotates the quick coupler in the correct direction (counterclockwise at the figures 1 to 4 ) to lock the coupler to the bucket connection device, the cutouts 300 cover the other axis 5 of the bucket from above.

[0043] 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.

[0044] 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.

[0045] Thus, as represented in the 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.

[0046] Tooth 509 has a rear surface that is inclined upwardly and rearwardly so that when springs 400 push 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 tooth 509 to pass into notch 501.

[0047] To the figure 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.

[0048] 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.

[0049] 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 bump 508 of the tooth 502, the dimensions of the nose 609 being suitable for penetrating the groove 511 in which the bump 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 of causing the tooth 509 to come out of the notch 501, thus unlocking the quick fastener.

[0050] 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 high 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.

[0051] In particular, the terms top and bottom and bottom and top are defined in relation to this vertical, the connecting device, fixed to the bucket, being located under the quick coupler, in the locked position.

Claims

1. Coupler device comprising a coupler, or quick coupler (1), intended to be secured to a public works machine, such as an excavator, a connection device (2), intended to be secured to a tool, such as a bucket (3), coupling means intended to couple the quick coupler (1) to the connection device (2) and locking means intended to lock the coupling; the connection device (2) comprising at least one trunnion (5); the coupler comprising a base body in which is defined a cavity (300) for rear reception of the trunnion (5), characterized in thatit comprises a lever (103) pivotally mounted between a closed position in which it holds the journal (5) in the rear receiving cavity (300) and an open position in which it does not hold the journal (5), the locking means being arranged to block or prevent rotation of the lever (103) in the closed position, the lever (103) being mounted movable in translation, in particular in the horizontal direction from the front side to the rear side, the locking means being arranged so as to push the lever (103) in a translational movement to put it in the closed position, in particular in the blocked state.

2. Device according to claim 1, characterized in that the axis (104) of rotation of the lever is received in at least one oblong through window (109), in particular two through windows formed in respective lateral flanks (102) of the base body.

3. Device according to one of claims 1 to 2, characterized in that the locking means comprise at least one spring (400), in particular two springs, which is / are fixed on the one hand to the body of the coupler, in particular a rear part (113) of the body of the coupler, and on the other hand to a front end part (111) of the lever (103).

4. Device according to claim 3, characterized in that the or each spring (400) is a tension spring tending to pull the lever (103) backwards.

5. Device according to one of the preceding claims, characterized in thatthe lever (103) comprises at least one upper branch (105), in particular two upper left and right lateral branches, and at least one lower branch (106), in particular two lower left and right lateral branches, which extend rearward from the axis (104) of the lever, the or each upper branch (105) extending further rearward than the or each lower branch (106), each pair of lower and upper branches respectively left and right defining a respective C-shaped cavity, in particular with an opening facing rearward, in which the journal (5) is received in the closed position.

6. Device according to one of the preceding claims, characterized in thatthe lever (103) comprises at least one front branch (107), in particular two front branches, right and left, extending forward from the axis (104) of the lever, the or each front branch consisting of a proximal section (108) continued by a distal section (111), which extends inclined relative to the proximal section (108).

7. Device according to claim 6, characterized in thatthe front branch (107) or each front branch passes through a respective through opening (112), in particular two respective left and right openings, of the base body to emerge from the upper surface of the base body, the front end or each front end of the distal section (111) or of each distal section being fixed to a front end of a respective spring (400) while the other end of the spring or of each spring is fixed to a respective stud (113) coming from the upper face of the base body, in particular substantially at the level of the upper rear edge of the base body.

8. Device according to one of the preceding claims, characterized in thatthe locking means comprise a lug (502) mounted at an upper rear end of the lever (103), in particular by being pivotable relative to the latter, in particular at the level of the rear end of the upper rear branch (105) or the rear ends of the upper rear branches.

9. Device according to claim 8, characterized in that the lug (502) comprises, on either side of its pivot 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 (502) tends, under the effect of its weight, to tilt in the direction tending to cause its rear part to fall downwards.

10. Device according to claim 8 or 9, characterized in that a torsion spring (505) is mounted so as to act on the lug (502), in particular so as to force the rear part (506) downwards.

11. Device according to one of the preceding claims, characterized in that the locking means comprise a rear plate (500) forming a stop mounted at a rear end of the coupler, so that, in the locked closed position of the lever, a part of the lever (103) abuts against the rear plate (500) and is thus prevented from moving forward.

12. Device according to one of the preceding claims, characterized in that a tooth (509) projects downwards from the rear part of the lever (103), in particular from the lug (502), a notch (501) being formed in the upper edge of the rear plate (500), on the rear side of the plate, and in the locked closing position, the tooth (509) is received in the notch (501).

13. Device according to one of the preceding claims, characterized in that the rear receiving cavity (300) is open downwards.

14. Device according to one of the preceding claims, characterized in thatthe coupling means comprise at least one front hook (7), in particular two left and right lateral front hooks, projecting from the front of the base body and the connection device (2) comprises two pins (5, 6), one intended to be received in the rear receiving cavity (300) and the other in a front receiving cavity (200) or cavities defined by the hook (7) or the front hooks, the coupler, or quick attachment (1), comprising a base plate from which two lateral flanks (102) project downwards, each flank ending on the front side with a respective hook (7).

15. Public works machine comprising a lifting element, in particular a lifting arm, and a tool, in particular a bucket (3), and a quick coupler device according to one of the preceding claims, the quick coupler or attachment (1) being fixed to the lifting element, while the connection device (2) is fixed to the tool.

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