Quick coupler

Abstract

Quick coupler for connecting a work tool to a working arm of a work machine, the quick coupler comprising: a coupler body including first and second recesses configured to receive first and second attachment pins of an implement therein, respectively; wherein the first and second locking members are movable between an unlocked and a locked position for locking the first and second fixing pins in the first and second recesses, respectively; an actuator configured to move the first locking member between the unlocked and locked positions; and a biasing arrangement configured to bias the first locking member into the locked position in the event of an actuator failure, wherein the biasing assembly is further configured to move the second locking member to the locked position when the first locking member is moved to the locked position by the actuator.

Description

REGIONThe present teachings relate to a quick coupler for attaching a work implement to a work arm of a work machine.BACKGROUNDWork machines, also known as off-road vehicles, typically include a working arm pivotally connected to the body of the machine and a work implement, such as a bucket or a grab, attached to the end of the arm via a coupling device. Attachment of the working machine enables the working machine to perform working operations.Such coupling devices usually comprise a so-called quick coupler for connecting various working tools to the working arm. Quick couplers tend to include an actuator-operated locking mechanism that can selectively lock and unlock two attachment pins of a working implement with respect to the quick coupler for connecting and disconnecting the working implement to and from the quick coupler.The present invention seeks to provide an improved fast coupler.SUMMARYThe present invention relates to a quick coupler for connecting a working implement to a working arm of a working machine according to the appended claims.The present disclosure provides a quick connector coupler comprising a coupler body comprising first and second recesses configured to receive first and second attachment pins of a work implement therein, respectively.The first and second locking members may be movable between unlocked and locked positions for locking the first and second mounting pins in the first and second recesses, respectively.An actuator may be configured to move the first locking member between the unlocked and locked positions.A biasing arrangement may be configured to bias the first latch member to the locked position if the actuator fails.The biasing assembly may be further configured to move the second locking member to the locked position when the first locking member is moved to the locked position.The use of the biasing arrangement which provides a fail-safe for the actuator and first locking members allows the actuating force to be practically provided to the second locking members. Further, the actuation force achieved with the biasing assembly may be limited to prevent the second locking members from being forced if one of the mounting pins is misaligned.The actuator may be configured to move the second locking members from the locked position to the unlocked position. Thus, the second locking members may be movable in a first direction, e.g., unlocked to locked, using the biasing arrangement and in a second direction, e.g., locked to unlocked, using the actuator. This is advantageous because dirt or foreign bodies accumulated in or around the lock during use can be easily displaced using the relatively large force of the actuator.The biasing assembly may be movable independently of the actuator. Thus, the actuator may be moved to engage the first locking member when the biasing assembly is prevented from moving, for example when the second locking member is locked or its complete locking is prevented. The biasing assembly may only engage the first locking member when the second locking member is fully engaged to the locked position.The first locking members may be subjected to an actuation force determined by the actuator. When moved from the locked to the unlocked position, the second locking members may be subjected to an actuation force determined by the biasing assembly. The actuation force of the actuator may be greater than the actuation force of the biasing assembly.A maximum actuation force for moving the second latch from the unlocked position to the locked position may be the maximum actuation force, e.g., the spring force, of the biasing assembly. Thus, the maximum operating force applied to the second lock mechanism can be restricted from the first lock members driven by the actuator. The actuation force for the biasing assembly may be less than the actuation force of the actuator.The biasing arrangement may comprise a compression spring.The second locking member may comprise a clamp. The clamp may be pivotally attached to the coupler body. The clamp may be configured to pivot into the second recess upon movement to the locked position and out of the second recess upon movement from the locked position to the unlocked position. By providing a pivoting clamp, the actuating force required to move the second latch member to the locked position is reduced, which is more suitable for use of the biasing member.A movement device may extend between the biasing assembly and the clamp. The movement device may be configured to pivot the clamp under action of the biasing member. The biasing assembly may be configured to linearly displace the moving device away from the second locking member to move the second locking member from the unlocked to the locked position. The linear displacement of the movement device under the action of the biasing member may cause the clamp to rotate about the pivot member.The movement device may include a lock latch positioned radially outward from the second latch member in the locked position. The lock bolt may be provided at a fixed radial distance from the depression in the locked position such that the lock bolt is configured to prevent movement of the second lock member to the unlocked position. The movement device may be limited to linear movement with respect to the second depression. The linear motion may be a tangential motion with respect to the second recess.The pivotable clamp may include a running surface on a radial outer side thereof. The clamp may comprise a plate-like member. The tread may be provided by an edge of the plate-like member. The clamp may be positioned in a plane normal to the longitudinal axis of the second recess / attachment pin. The locking bolt can pivot in the normal plane. The pivot axis may be aligned with the longitudinal axis of the second recess / second attachment pin.The lock bar may engage the tread during linear displacement of the lock bar to cause pivoting of the clamp. The tread may comprise a curved profile. The curvature of the tread may comprise a slight curvature.The movement device may include a recess in which the clamp is in the unlocked position. The depression may be positioned on a proximal side of the lock bar with respect to the first locking member. Thus, the lock bar may be positioned distally with respect to a central portion of the coupler body. The locking bar may be the distalmost portion of the clip.The second locking member may be biased to an unlocking position. Thus, when the first locking member is retracted into the coupler body by the actuator and the biasing force of the biasing arrangement on the second locking member is released, the second locking member can be opened via a biasing member for the second locking member. For example, the clamp may be opened using a clamp biasing member, which may be, for example, a torsion spring. The clamp biasing member may be configured to pivotally urge the clamp radially outward to the unlocked position.The quick connector may further include an actuation axis along which the first locking member moves between the unlocked and locked positions. The first locking members may be elongated and extend in the direction of the actuation axis. The first well and the second well may define a front portion and a rear portion of the quick coupler, respectively. The operating axis may extend forward and rearward with respect to the front part and the rear part.The compression spring may include a longitudinal axis aligned with the actuation axis of the first locking members.The actuator may comprise a linear actuator, e.g. a hydraulic cylinder. The actuation direction of the linear actuator can run along the actuation axis. The hydraulic cylinder may comprise a body and a rod with a drivable piston mounted in the body. The rod may be aligned with the actuation axis. The hydraulic cylinder may be connected to the first link via a pin. The rod may be connected to the first locking member, optionally via an intermediate structure such as a slide. The full bore end of the cylinder may be secured proximate the second locking members. The full bore end may be pin attached to the coupler body.The quick coupler may further comprise a pair of laterally displaced first locking members. The first locking members may each comprise an elongate body (which may be referred to as pins or rods). The elongated bodies may be provided near an edge of the coupler body. The actuator may be positioned between the pair of laterally displaced first locking members. The actuator may be along a centerline of the quick coupler.The first locking members may be connected by a carriage. The carriage may include an elongate member extending widthwise across the quick coupler and attached to the first locking members at the ends thereof. The actuator may extend between the coupler body and the carriage.The biasing arrangement may comprise a biasing member extending between the carriage and the coupler body. The biasing assembly may press against a back side of the carriage. The locking members may be mounted on the front side of the carriage.The quick coupler may include a pair of first locking members and a pair of second locking members. Each pair of first and second locking members may comprise a respective biasing member of the biasing assembly. The biasing members may be aligned with the actuation axis. The biasing members may be aligned with the longitudinal axis of the first locking members. The biasing members may be coaxial with the first locking members.The first locking members may comprise an elongate body having a locking portion and a guide extending rearwardly therefrom. The guide may extend along a longitudinal axis of the locking portion, i.e. be coaxial with the locking portion.The guide may comprise a rod received in a guide recess for at least a portion of the stroke of the first locking member. The guide recess may be provided at a distal end of the guide. The guide recess may be provided in the coupler body, optionally in a plate member of the coupler body. The guide recess may be located near the second locking members.Each respective biasing member may be positioned around a guide for a first locking member.The quick coupler may include a display arrangement configured to display when the first and / or second locking members are in the unlocked and / or locked positions. The display assembly may include the second latch member or the lock latch.The present disclosure provides a work machine including: a body; a ground engaging drive structure supporting the body; and a working arm fixed to the body. The quick coupler may be attached to a distal end of the working arm.The body may include a chassis supported by the ground engaging drive structure and a structure, e.g., a rotatable structure, connected to the chassis. The working arm is attached to the structure.The quick coupler can be used to attach a swing rotator attachment to the end of a working arm.The work machine may be an excavator. The work machine may be a backhoe loader, a swing excavator, a track excavator, or a wheel excavator. The work machine may be any work machine including a work arm in which the quick coupler of the disclosure can be used well.It will be apparent to those skilled in the art that a feature described with respect to any of the aspects, embodiments, or examples described herein may be applied to any other aspect, embodiment, or example, respectively, unless mutually exclusive. Furthermore, any feature described herein may be applied to any aspect and / or combined with any other feature described herein unless mutually exclusive.BRIEF DESCRIPTION OF THE DRAWINGSEmbodiments will now be described with reference to the accompanying drawings, in which: FIGS. 1 and 2 are bottom isometric views of a quick coupler in accordance with the present disclosure; FIGS. 3 ato 3 c show sectional views of the quick coupler of FIGS. 1 and 2 in an unlocked or locked or partially locked position; FIG. 4 is an exploded view of the quick coupler of FIGS. 1 and 2; and FIG. 5 is a side view of a work machine that may include the quick coupler of the present disclosure.Detailed DescriptionGenerally, the invention is generally generally practicedIn the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of various embodiments and the inventive concept. It will be apparent to those skilled in the art that: the present invention may be practiced without these specific details or with known equivalents of these specific details; the present invention is not limited to the described embodiments; and the present invention may be practiced in various alternative embodiments. It should also be understood that well-known methods, procedures, components, and systems may not have been described in detail.Referring to FIGS. 1-4, a quick connector 10 is provided that is connectable to a working arm of a work machine ( 510, FIG. 5 ) to connect a work implement 552 to the work machine. The quick connector 10 includes a connector body 12 that includes first and second pairs of recesses 14, 16 for receiving therein first and second attachment pins 18, 20 of a work implement.The quick coupler 10 also includes first and second pairs of locking members 22, 24 movable between locked and unlocked positions for locking the first and second mounting pins 18, 20 in the first and second recesses 14, 16, respectively. An actuator 26 is configured to move the first locking members 22 between the locked and unlocked positions.A biasing assembly 28 is configured to bias the first latch members 22 to the latched position if the actuator 26 fails. Further, the biasing assembly is configured to move the second locking members 24 to the locked position when the first locking members 22 are moved to the locked position upon actuation of the actuator 26.Before proceeding, it is noted that the isometric views of FIGS. 1 and 2 include the first and second latch members 22, 24 simultaneously in the latched and unlatched positions to facilitate comparison. Thus, it can be seen in FIGS. 1 and 2 that one of the first locking members 22 aprotrudes from the coupler body 12 and blocks the respective portion of the first recess 14 and the other of the first locking members 14 bis in a retracted unlocked position. Similarly, the second locking member 24 acorresponding to the first locking member 22 ais shown in a locked position with the other 24 bshown in the unlocked position.It will be appreciated that in practice the locking members 22, 24 would operate in accordance with the first and second locking members 22, 24 operable together instead of separately. Thus, the two first locking members 22 typically protrude into the first recesses 14 and are retracted together into the coupler body 12 when the actuator 26 is moved in one direction. Likewise, the second locking members 24 typically protrude into the second recesses 14 and are retracted equally together into the coupler body 12 when the actuator 26 is moved in one direction. It will be understood, however, that the second latch members 24 may be individually actuated by separate biasing members 28a and 28b, as shown and described in connection with Figure 3c.It will be apparent to those skilled in the art that the orientation of the quick coupler 10 in use is dependent upon the orientation of the working arm of the working machine. For purposes of the disclosure, the forward portion of the quick coupler includes the first depression, and the rearward portion includes the second depression, as indicated in FIG. 3 a. The lower part of the quick coupler 10 can be regarded as the side to which the working implement is attached, the upper side being the side to be connected to the working arm.The coupler body 12 may be integrally formed, e.g., integrally molded, as a unitary component. It should be appreciated that in alternative arrangements, the coupler body 12 may be manufactured, forged, or formed using any suitable manufacturing process. The coupler body 12 includes the first recess 14 and a second recess 16 at opposite ends thereof. As noted, the first recess 14 is arranged to receive a first attachment pin 18 of a work implement therein and the second recess 16 is arranged to receive a second attachment pin 20 of the work implement therein. The spacing and size of the recesses may be classic with respect to the inclusion of classical fasteners.As can be seen from Figures 1 and 2, the recesses 14, 16 can be formed by appropriately shaped channels or cutouts in the coupler body 12. The recesses 14, 16 may include one or more surfaces for contacting the mounting pins 18, 20 and may have any suitable shape suitable for receiving and retaining the mounting pins 18, 20 when locked in position with the locking members 22. The contact surfaces may be continuous across the width of the coupler body 12 or may be separated at a central portion or lateral edges of the coupler body 12. The interfaces may be provided, for example, by one or more tabs on the locking members 22, 24.The recesses 14, 16 may comprise a U-shaped or J-shaped channel such that the mounting pins 18, 20 can be received only from specific directions. As seen in Figures 1 and 2, the first and second recesses 14, 16 each include a continuous mating surface extending across the entire width of the coupler body 12 and additionally include tabs for providing additional mating surfaces on the locking members 22, 24. the first recesses 14 are provided with a J-shaped profile (as viewed from the side) that contacts about half of the mounting pin 18, the locking member 22 blocking the open side in the locked position to prevent withdrawal of the mounting pin 18. The second recesses 16 comprise a U-shaped channel. The second locking members 24 extend radially through a wall of the U-shaped channel, again to block the opening and prevent withdrawal.It should be understood that the specific arrangement of the recesses 14, 16 and the corresponding locking members 22, 24 may vary between embodiments and the variations shown and described herein are not limiting.As noted above, the first locking members 22 are movable between a locked position shown in FIGS. 1, 2, 3 band 3 cand an unlocked position shown in FIGS. 1, 2 and 3 a. The second locking members 24 are movable between a locked position, also shown in FIGS. 1, 2 and 3 b, and an unlocked position, shown in FIGS. 1, 2 and 3 a. FIG. 3 cshows the second locking member 24 in a partially locked state, in which the second fastening pin 20 is not completely received in the second depression 16 and thus prevents a complete stroke.The arrangement of the actuator 26, the first locking members 22, and the biasing assembly 28 may be such that the actuator 26 and the first locking members 22 are biased by the biasing assembly 28 to the locked position. Thus, for movement from the locked position to the unlocked position, the actuator 26 must functionally overcome the biasing force of the biasing assembly 28 to retract the first locking members 22. Once the unlocked position is reached, the actuator 26 may be locked to maintain the position against the biasing force of the biasing assembly 28. For example, in the case of an actuator 26 in the form of a hydraulic cylinder, a valve (not shown) may be actuated to prevent the flow of hydraulic fluid and movement of the actuator 26.When moving from the unlocked to the locked position, the actuation direction of the actuator 26 may be reversed such that the first locking members 22 protrude from the coupler body 12 and extend into the recess 14. The first latch members 22 may be operated primarily by the actuator 26, with the biasing assembly 28 providing only some redundancy in the event of a failure. However, in some embodiments, the biasing assembly 28 may be sufficient to actuate the first locking members 22 without the action of the actuator 26. That is, in some embodiments, the function of the actuator 26 may be limited to only unlocking the first locking members 22.The second locking members 24 may be actuated by the biasing assembly 28 when the first locking members 22 and the actuator 26 are moved between the unlocked position and the locked position. As noted, actuation of the biasing assembly 28 may be controlled and / or limited by the position of the actuator 26 such that the second latch members 24 require actuation of the main actuator 26 for operation. However, the actuation force acting on the second locking members 24 is provided only by the biasing assembly 28. That is, the second locking members 24 may be driven by the biasing assembly 28 in conjunction with movement of the first locking members 22 from the unlocked to the locked position or subsequent thereto.When moved from the locked to the unlocked position, the second locking members 24 may be directly actuated by the actuator 26 as it retracts the first locking members 22 and moves the biasing assembly 28 rearward.The first attachment pin 18 of a work implement may be locked in the first recesses 14 by first receiving the first attachment pin 18 in the first recesses 14 with the first locking members 20 in the unlocked position and then moving the first locking members 20 to the locked position. When the first fixing pin 18 is locked in the first recesses 14 as described, it is prevented from coming off the coupler body 12 and is thus connected to the coupler body 12. The first attachment pin 18 may be unlocked from the first recesses 14 by moving the first locking members 20 from the locked position to the unlocked position, thereby allowing removal of the first attachment pin 18 from the first recess 14.The second attachment pin 20 of the implement may be locked in the first recesses 16 by first receiving the second attachment pin 20 in the second recess 16 with the second locking members 24 in the unlocked position and then moving the second locking members 24 to the locked position. When the second fixing pin 20 is locked in the second recess 15 as described, it is prevented from coming off the coupler body 12 and is thus connected to the coupler body 12. The second mounting pin 20 is then unlocked from the second recess 16 by moving the second locking members 24 from the locked position to the unlocked position, thereby allowing removal of the second mounting pin 20 from the second recess 16.It should be appreciated that due to the particular shape of the first and second recesses 14, 16 of the embodiment shown in the drawings, it may be necessary for the second mounting pin 20 to be received in the second recess 16 before the first mounting pin 18 is received in the first recess 14 by determining the separation of the mounting pins 20.In the illustrated embodiment, the first locking member 20 includes a pair of elongated pins extending along respective longitudinal axes 22- 2. The first locking members 22 are slidably received in respective bores defined in the coupler body 12. The first locking members 20 and the bores have corresponding profiles such that movement of the first locking member 20 relative to the coupler body 12 is limited to the longitudinal axes 22- 2 of the first locking member 20. As shown in the exploded view of FIG. 4, in some embodiments, the bore may include a linear bearing.The first locking members 22 may include a locking portion 22- 1 extending forward and a guide 32 extending rearward from the locking portion 22- 1. The first locking members 22 are connected as shown by a carriage 30 movable by the actuator 26 to actuate the first locking members 22. In the illustrated embodiments, each of the first locking members 22 includes a guide 32, however, it should be understood that the guide 32 may be omitted or additionally or alternatively provided on the carriage 30.Each guide 32 extends between the locking portion 22- 1 along the longitudinal axis 22- 2 and a guide recess 34 in the coupler body 12. The guides 32 may be separated from the guide recess 34 when the first locking members 22 are in the extended positions to allow some movement of the locking portion 22- 1 during engagement with the mounting pin 18. However, this is not limiting and the guides 32 may have a sufficient length regardless of position relative to being positioned in the guide recess 34.The carriage 30 may include a body extending between each of the pair of first locking members 22 and movable along the longitudinal axes 22- 2 of the first locking member 22 under the action of the actuator 26. In the embodiment shown, a single actuator 26 is provided which is connected to the centre of the carriage 30 between the two locking members 22a, 22b. However, this is not limiting, and in some embodiments, the actuator 26 may be positioned elsewhere relative to the carriage 30, and there may be multiple actuators. For example, in some embodiments, each of the first locking members 22 a, bmay be provided with its own actuator.The locking members 22 may be provided as a unitary body including the locking portion 22- 1 and the guide 32. The locking portion 22-1 may comprise a generally cylindrical body having a diameter greater than the guide 32, the two portions being separated by a shoulder abutting the carriage 30. It should be appreciated that in some embodiments, the locking portion 22- 1 and the guide 32 may be formed from separate components that are assembled together and attached to each other to provide the unitary structure.The first locking members 22 may be attached to the carriage 30 using any suitable fastener. In the example shown, the first locking members 22 include a threaded portion behind the carriage for receiving a nut 36.The guide recess 34 may be provided by a wall of the coupler body 12 or a guide plate 38 that is received by and / or attached to the coupler body 12. In the embodiment shown, the guide recess 34 is provided by a guide plate 38 which is received in a corresponding seat which may be provided between opposing portions, e.g., flanges, of the coupler body 12. The seat and positioning plate 38 may include suitable positioning features, such as the curved lateral edges, that ensure proper alignment of the plate 38 with the guide 32.In the embodiment shown in the drawings, the guide plate 38 includes a short circumferential shoulder 40 around the guide recess 34. The tab 40 may protrude forward toward the locking portion 22- 1 and positions the biasing member 28, as will be described in more detail below.The quick coupler 10 includes an actuator 26 configured to move the first locking members 20 between the locked and unlocked positions. The actuator 26 is configured to be actuated in conjunction with the biasing member 28 to move the second locking members 24 between the locked and unlocked positions. The actuator 26 may be positioned in a cavity in the coupler body 12 and may be disposed between the first locking members 22.In the embodiment shown, the actuator 26 is a linear hydraulic actuator in the form of a hydraulic cylinder. The actuator 26 includes an actuator body 26-1 and a rod 26-2 to which a piston (not shown) is secured defining one or more working chambers on either side thereof, as is well known in the art. The actuator 26 is configured to selectively advance and retract the rod 26- 2 relative to the actuator body 26- 1 to move the first locking members 22 between the locked and unlocked positions along an actuation axis corresponding to the longitudinal axes 22- 1 of the first locking members 22. In alternative embodiments (not shown), the actuator 26 may be an electronic or pneumatic actuator.Actuator 26 is generally elongated and extends between carriage 30 and a mount on coupler body 12. actuator 26 may be mounted in any suitable manner, such as a pin mount at the full bore end and a pin mount between rod 26-2 and carriage 30, as shown. Other attachment methods, well known in the art, are possible.The actuator 26 is fixed centrally between the two first locking members 22 and provided in a plane defined by the two first locking members 22 disposed on both sides thereof. It will be appreciated that by providing a planar arrangement of the actuator 26 and the first locking members 22, a reduction in the depth of the quick coupler 10 is facilitated, which is generally advantageous. However, in some cases, the actuator may be offset from the plane that extends between the two first locking members 22.As noted, all of the first locking members 22 are biased to the locked position via a biasing arrangement 28 that provides a biasing force at the rear of the locking portion 22- 1 to urge the first locking members 22 to a locked position. Thus, when the actuator 26 is not applying a force to the first latch 22, such as when the actuator 26 is no longer receiving current or fails, the biasing assembly 28 is configured to maintain the latch 22 in the latched position using the spring force of the biasing assembly 28. The actuator 26 thus must overcome the biasing assembly 28 to move the first latch 22 from the latched position to the unlatched position.The biasing assembly 28 may include a pair of biasing members 28 a, 28 bconfigured to bias each of the first locking members 22 to the locked position.In the illustrated embodiments, biasing members 28a,b extend longitudinally between first locking members 22 and coupler body 12, and a first end 28-1 of biasing member 28a engaged with coupler body 12 and a second end 28-2 engaged with first locking member 20 behind carriage 30 are shown.As shown, the biasing members 28 a, 28 bmay be resilient members such as a compression spring, but in alternative embodiments any suitable biasing member or arrangement may be used. The use of a compression spring is particularly advantageous since it can be received over the guide 32 so that the prestressing force is coaxial with the longitudinal axis of the locking members 22 and the actuating axis. Compression springs also provide a robust and predictable mechanical force.The first and second ends 28- 1, 28- 2 of the biasing members 28 a, bmay be attached in any suitable manner. In the embodiment shown, a first end 28-1 of the compression springs is secured over the shoulder 40 provided around the guide recess 34 which is dimensioned to assist in radial positioning of the compression spring. The second end 28-2 of the compression spring is pressed against the back of the carriage 30. As will be described below, the biasing member 28 may be operatively attached to the second locking members 24 such that advancement or retraction of the biasing member 28 causes the second locking member 24 to move between the locked and unlocked positions.The biasing members 28 are arranged to deflect from a first more compressed state when the first and second locking members 22, 24 are unlocked to a second less compressed state when the first and second locking members 22, 24 are in a locked position. It should be appreciated that a very high compressive force is provided by the biasing members 28 when the first locking members 22 are in a locked position to provide the replacement actuation force described above.The second locking members 24 may include a pivotally mounted clamp configured to rotate relative to the respective recess and partially surround or otherwise engage or block the mounting pin 20 when properly positioned within the second recess 16. Thus, the clamp may move relative to the second recess 16 from a radially outer position when the second locking member 24 is unlocked to a radially inner position when the second locking member 24 is locked.The clamp lies and pivots in a plane generally normal to the central axis of the recess 16 (which corresponds to a longitudinal axis of the mounting pin 20). The pivot axis may be generally parallel to the longitudinal axis of the mounting pin 20 such that the clamp moves radially and in the normal plane of the mounting pin 20. In the orientation shown, the clamp is provided over the mounting pin 20, i.e. on the working arm side, but this is not limiting and other orientations are possible. The pivot mount 43 is shown above and behind the guide recess 34, however, the position may vary.In the embodiment shown, the clip is movably received in a slot 44 provided in the coupler body 12 and flanked by lateral walls.The clamp may be biased to an open configuration by a clamp biasing member 46. The clamp biasing member 46 may be any suitable device that forces the clamp to the open / unlocked position. In the illustrated embodiment, the clamp biasing member 46 includes a torsion spring.The illustrated torsion spring has a main body 46-1 that includes a central passage centered on a boss coaxial with pivot mount 43, and a pair of spring arms 46-2 configured to engage opposing surfaces of coupler body 12 and a point of attachment to the clamp. The biasing member 46 is biased to maintain the clamp in the unlocked position when the actuator 26 and the first locking members 22 are retracted to the unlocked position. When the clamp is moved to the locked position, the clamp is pivoted against the spring force of the biasing member 46.The quick coupler 10 includes a pair of second locking members 24, each of the pair corresponding to one of the first locking members 22. Thus, the biasing member 28 aassociated with the first locking member 22 ais configured to actuate the second locking member 24 a, and the biasing member 28 bassociated with the first locking member 22 bis configured to actuate the second locking member 24 b.A mechanical linkage between the respective biasing members 28 a, band the second locking members 24 a, bis provided by the mover 48. The mover 48 is configured to move linearly between a first position corresponding to the unlocked position of the second lock member 24 and a second position corresponding to the locked position. The movement of the movement device 48 is influenced by the movement of the respective prestressing element 28 during rebound and rebound with the movement of the actuator 26.The movement device 48 includes an elongated body 48-3 having a mounting portion 48-1 attached to the biasing member 28 at a first end and a clamp portion 48-2 drivingly engaged with the clamp to move it between the locked and unlocked positions during actuation of the biasing member 28 at a second end.The actuation of the mover 48 and the engagement with the clamp may be any manner for causing the clamp to move. In the illustrated embodiment, the mover 48 is generally linearly displaceable along the longitudinal axes 22- 2 of the first locking members 22.The movement device 48 provides a direct connection such that movement of the biasing member 28 results in corresponding movement of the clamp. Thus, as the biasing members 28 deflect upon movement from the unlocked to the locked position, the mover 48 is pulled into the coupler body 12.The clamp portion 48-2 may include a latch 48-4 positioned on a radially outer surface of the clamp so as to contact the clamp and move it from the unlocked position to the locked position when the mover 48 is linearly retracted into the coupler body 12. Once the locked position is reached, the latch 48-4 is on the radially outer surface of the clamp, thereby limiting outward movement and ensuring that the mounting pin 20 is retained in the recess 16.The lock bar 48-4 includes an axial length having a front edge 48e which engages the upper surface of the clamp. An opening or recess 48-5 is provided upstream of the front edge 48e in which the clip can be received in the unlocked position to allow the clip to move radially outwardly from the recess 16 under the action of the clip biasing member 46.In the illustrated embodiment, the tread 45 engaging the lock latch 48-4 is angled toward the actuation axis of the mover 48 in the unlocked position such that the rearward linear movement of the mover 48 along the tread 45 causes the clamp to be radially displaced. The shape of the tread may be modified in various ways to meet a desired actuating motion. In the illustrated embodiment, the tread 45 includes a curve, however, in some variations, an angled surface including one or more facets may be preferred. Once the locked position is reached, the tread 45 is positioned below, i.e., radially inward of, the latch 48- 4 and aligned with the actuation axis 22- 2.In the illustrated embodiment, the clamp portion 48-2 includes a pair of arms that extend from the body 48-3 to the outer end. The latch bar 48-4 connects the ends of the arms. The separation of the arms upstream of the lock bolt 48- 4 defines the opening / recess in which the clip 48 is received in the unlocked position.In addition to the lock bar 48-4 and the aperture / recess, the clamp may include an elongated channel 42 that receives the running surface 45 of the clamp to maintain a degree of engagement therebetween and maintain alignment in the unlocked configuration.The movement device 48 may have any suitable shape that allows connection between the biasing members 28 and the clamp. In the illustrated embodiment, the mover 48 includes a generally L-shaped member, with the attachment portion 48-1 provided by the leg of the L-shape and the body 48-3 provided by the foot that is horizontally oriented.The attachment portion 48- 1 includes a through hole in which the guide 32 of the respective first locking member 22 is received. The attachment portion 48- 1 is provided upstream of the biasing member 28, e.g., between the biasing member 28 and the carriage 30 or the locking portion 22- 1, such that when the second end of the biasing member 28 moves, the moving device 48 is slid with respect to the clamp to actuate the second locking member 24.The mover 48 and the first lock member 22 are provided in a floating arrangement such that the mover 48 is not moved by the first lock member 22 or the actuator 26 when the clamp or the biasing member 28 cannot move. Thus, if the actuator 26 is actuated and the first locking members 22 move to the locked position but the clamp is locked, for example, if the mounting pin 20 is not properly inserted into the recess 16, the actuator may continue operation without forcing the clamp. That is, the operating force on the second lock member 22 is limited to the spring force of the biasing member 28.Figures 3a-3c show the operation of the quick coupler 10. In Figure 3a, the coupler 10 is shown in an unlocked state in which the mounting pins 18, 20 are positioned in the recesses 14, 16, but the actuator 26 is not operated to actuate the first and second locking members 22, 24. Thus, the first locking member 22 is shown in a retracted position and housed within the coupler body 12. Likewise, the second latch member 24 is maintained in an unlocked configuration in which it is received in the recess 48- 5 of the mover 48 and is maintained in the open position under the action of the clamp biasing member 46.Figure 3b shows the quick coupler 10 in a locked configuration in which the actuator 26 has been actuated to move the first locking members 22 out of the coupler body 12 into the first recess 16, partially blocking the recess 14 and preventing removal of the mounting pin 20.Due to the movement of the actuator 26 and the associated displacement of the first locking members 22, the biasing member 28 may freely deflect, thereby displacing the moving device 48 and the latch 48- 4 to press against and move the clamp radially inward to secure the second attachment pin 18. The mover 48 and the clamp remain in this position under the action of the biasing member 28 until the actuator 26 is actuated in the opposite direction to overcome the biasing force and pull the first latch member 22 and the mover 48 back to the positions shown in FIG. 3 a.Fig. 3c shows a partially received fastening pin 21 in the second recess 16. In conventional quick couplers, if the fastening pins 20 are not correctly received in the recesses 16 before actuation, the locking members 24 can be forced directly to the fastening pins 20, thereby causing damage to these or both. An advantage of actuating the second latch members 24 using a spring force is that the actuation is released from the full force of the actuator and the actuation force at the clamp is limited to that of the biasing member 28 that rebounds against the mover 48.Thus, as shown in FIG. 3 c, the actuator 26 has urged the first latch member 22 to a position that allows the biasing member 26 to rebound. However, the movement of the clamp is blocked by the mounting pin 20, thereby restricting the inward displacement of the clamp. Thus, while the clip does not lock the mounting pin in position, significant damage is also prevented due to the limited force that can be applied by the biasing member 26.As noted above, the mover 48 may include a recess 48- 5 in which the clamp may be received in the unlocked position. In the illustrated embodiment, the recess 48- 5 includes a recess that extends completely through the body 48- 3 of the mover 48 such that the clamp may be visible from a radially outer position. When the mover 48 is fully engaged, the clamp is positioned below the latch 48-4.In some embodiments, an indicator recess 50 may be provided in the coupler body 12 above the clamp so that the position of the clamp is recognizable to an operator seated in a machine cab or located outside the machine. This provides a display that can be used by the operator or an inspector to determine whether a successful intervention has been achieved. It is understood that other displays known in the art may also be possible.Another advantage of providing a recess 48-5 extending completely through the mover 48 is that it helps prevent accumulation of dirt and debris between the mover 48 and the clamp, thereby assisting in ensuring reliable operation of the clamp during an unlocking operation.Referring to FIG. 5, a work machine 510 is illustrated. In the present embodiment, an excavator may be used as the work machine 510. Work machine 510 could be any type of work machine, such as an excavator with any deployment weight, loader, tele loader, etc. Such work machines may be referred to as off-road vehicles.The ground engaging drive structure includes a first or front axle A1 and a second or rear axle A2, each axle being coupled to a pair of wheels 562, 564. In further embodiments, the ground engaging drive structure may include a pair of tracks. One or both of the axles A 1, A 2 may be coupled to a drive assembly (not shown) configured to drive movement of the ground engaging drive structure (i.e., axles A 1, A 2). The drive arrangement causes movement of work machine 510 on a ground surface. The drive arrangement comprises a drive unit and a transmission. The prime mover may be an internal combustion engine, an electric motor, or a hybrid including both an internal combustion engine and an electric motor.Work machine 510 includes a body 566 supported on the ground engaging drive assembly. The body 566 of the work machine 510 includes a chassis 568 supported on the ground engaging drive assembly. A body 570 is connected to the chassis 568. The body 570 is connected to the chassis 568 by a mounting assembly 572.In the arrangement shown, the mounting arrangement 572 is a pivot mechanism in the form of a swivel ring. The mounting arrangement 572, in this embodiment, permits unrestricted rotation of the structure 570 relative to the chassis 568. It should be appreciated that in alternative arrangements, the structure 570 may not be able to rotate with respect to the chassis 568.A cab 574 from which an operator can operate the work machine 510 is mounted on the structure 570. The cab 574 includes an operator seat (not shown). It should be appreciated that in some arrangements, work machine 510 may not include cab 574 and the operator seat may be directly attached to body 566 of work machine 510.Work machine 510 includes a work arm 576. The operating arm 576 is connected to the body 566 and is provided for performing operations. The working arm 576 is connected to the body 566. In the arrangement shown, the working arm 576 is connected to the structure 570. Work machine 510 includes a counterweight 578 having a mass for balancing work arm 576. The counterweight 578 is provided on the structure 570. It will be appreciated that the counterweight may be omitted in alternative arrangements.A working implement 580 in the form of a bucket is attached to the end of the working arm 576 via a coupling device 582. The working device 580 comprises the fastening pins 18, 20 which are to be received by the depressions 14 and 16 of the quick coupler 10. Thus, in use, the quick coupler may be attached to the end of the working arm 576 and used to engage the working implement 580.Although the teachings have been described above with reference to one or more preferred embodiments, it should be understood that various changes or modifications may be made without departing from the scope defined in the appended claims.

Claims

A quick coupler for connecting a work implement to a work arm of a work machine, the quick coupler comprising: a coupler body comprising first and second recesses configured to receive first and second attachment pins of a work implement therein, respectively; wherein the first and second locking members are movable between unlocked and locked positions for locking the first and second attachment pins in the first and second recesses, respectively; an actuator configured to move the first locking member between the unlocked and locked positions; A biasing assembly configured to bias the first locking member to the locked position if the actuator fails, the biasing assembly further configured to move the second locking member to the locked position when the first locking member is moved by the actuator to the locked position.The quick connector of claim 1, wherein the actuator is configured to move the second locking members from the locked position to the unlocked position.The quick coupler of claim 1 or 2, wherein the biasing assembly is movable independently of the actuator.The quick coupler of any preceding claim, wherein a maximum actuation force for moving the second locking member from the unlocked position to the locked position is the maximum actuation force of the biasing assembly.A quick coupler according to any preceding claim, wherein the biasing arrangement comprises a compression spring.The quick connector of any preceding claim, wherein the second locking member comprises a clamp pivotally attached to the connector body.The quick coupler of claim 6, further comprising a moving device extending between the biasing assembly and the clamp, the moving device configured to pivot the clamp under action of the biasing member.The quick connector of claim 7, wherein the biasing arrangement is configured to linearly displace the moving device away from the second lock member to move the second lock member from the unlocked to the locked position.The quick coupler of claim 8, wherein the moving device comprises a lock bolt positioned radially outward from the second lock member in the locked position to prevent movement of the second lock member to the unlocked position.The quick coupler of claim 9, wherein the pivotable clamp comprises a tread surface on a radially outer side thereof, and wherein the latch engages the tread surface during linear displacement of the mover to cause pivoting of the clamp.The quick coupler of claim 10, wherein the tread is curved.The quick coupler of any of claims 7 to 11, wherein the moving device comprises a recess in which the clamp is in the unlocked position, the recess being positioned on a proximal side of the lock bolt with respect to the first locking member.The quick connector of claims 6 to 12, further comprising a clip biasing member, optionally a torsion spring, configured to pivotally urge the clip radially outward to the unlocked position.The quick connector of any preceding claim, further comprising an actuation axis along which the first locking members move between the unlocked and locked positions.The quick coupler of claim 14 when dependent on claim 5, wherein the compression spring comprises a longitudinal axis aligned with the actuation axis of the first locking members.The quick coupler of any preceding claim, wherein the actuator comprises a linear actuator, e.g. a hydraulic cylinder.The quick connector of any preceding claim, further comprising a pair of laterally displaced first locking members, the first locking members being connected by a carriage.The quick coupler of claim 17, wherein the actuator extends between the coupler body and the carriage, optionally wherein the biasing arrangement presses against a rear side of the carriage that is opposite the first locking members.A quick connector according to any preceding claim, comprising a pair of first locking members and a pair of second locking members, each pair of the first and second locking members comprising a respective biasing member of the biasing arrangement.A quick connector according to any preceding claim, wherein the first locking members comprise an elongate body having a locking portion and a guide extending rearwardly along a longitudinal axis of the locking portion, the biasing arrangement comprising a compression spring disposed coaxially on the guide.A quick coupler according to any preceding claim, comprising a display arrangement configured to display when the first and / or second locking member is in the unlocked and / or locked position, the display arrangement comprising the second locking member or, insofar as dependent on claim 9, the locking latch.A work machine comprising: a body; a ground engaging drive structure supporting the body; and a working arm attached to the body, wherein a quick coupler according to any one of claims 1 to 21 is attached to a distal end of the working arm.The work machine of claim 22, wherein the body comprises a chassis supported by the ground engaging drive structure and a structure, e.g., a rotatable structure, connected to the chassis, and wherein the working arm is attached to the structure.

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