Quick coupler automatic locking mechanism and method

A quick coupler and methods of coupling and decoupling a quick coupler and work tool are disclosed. The quick coupler includes a frame, cylinder, primary blocking member, secondary blocking member, biasing member, and controller. The method of coupling includes activating an AUTOMATIC LOCKING state, automatically locking a second tool pin within a hook, a first tool pin entering a notch, and activating a LOCKED state. The method of decoupling includes activating the AUTOMATIC LOCKING state, resting the work tool on a surface, activating an UNLOCKED state, and separating the quick coupler and work tool. Advantageously, the quick coupler can automatically lock the second tool pin without actuation of the cylinder.

TECHNICAL FIELD

The present disclosure generally relates to attachments and work tools for a work machine and, more specifically, to a quick coupler having an automatic locking mechanism.

BACKGROUND

Quick couplers are intermediate attachments for work machines which enable the machine to efficiently switch between different work tools. A quick coupler may be directly connected to an arm of a work machine, which may be an excavator, backhoe, front-end loader, and the like; and the coupler may be movable and actuated by one or more hydraulic cylinders of the work machine. A work tool, such as a bucket, hammer, auger, grapple, and many others, may be connected to the quick coupler through a locking mechanism of the coupler. The work tool may then be maneuvered by the work machine and/or may have the same range of motion as if it were directly connected to the arm. Advantageously, attachment and detachment of the work tool onto the quick coupler may be much quicker and easier than attachment or detachment onto the work machine directly. Moreover, quick couplers are capable of interfacing with a wide range of work tools, even those from different manufacturers.

A pin grabber coupler is a type of quick coupler configured to interoperate with pin-on work tools. Specifically, one or more tool pins of the work tool may be respectively locked into one or more locking zones of the pin grabber coupler. In many prior art designs, the locking zones and the locking mechanism therein are controlled by a single actuator, a configuration which, while simple and efficient, may have disadvantages.

For example, many prior art couplers require an operator of the work machine to perform a precise series of actions to safely attach the tool to the coupler. First, to initially ‘grab’ the tool, the tool may need to be situated within a specific location with respect to the work machine. If the work tool is situated too far away, too high up, or with an improper angle with respect to its center of gravity and/or tool pin orientation, the operator may need to first reposition either the tool or the machine. Furthermore, according to some prior art designs, the work tool may not be fully secured during the period after which it is ‘grabbed’ but before the locking mechanism is fully locked, further stressing the need for delicate operator control. Accordingly, such single-actuator couplers may create potentially hazardous situations and allow little room for error on the part of the work machine's operator.

Other pin grabber couplers within the prior art have attempted to improve the above drawbacks by increasing a number of locking mechanisms and a number of locking actuators provided by the coupler. In such designs, the coupler may initially and independently lock onto a first tool pin of the work tool, thereby improving an ease and a security of the coupling maneuvers thereafter. One such example is disclosed by U.S. Pat. No. 10,323,379, invented by Thomas Friedrich and assigned to Kinshofer GMBH. Specifically, Friedrich teaches a quick coupler for a work machine, the coupler comprising a coupling mount and a locking mount configured to receive a first locking part and a second locking part, respectively, of a tool attachment. A securing element is associated with the coupling mount and may be independently actuated by a securing element adjustment actuator. Further, a locking element is associated with the locking mount and may be independently actuated by a locking element adjustment actuator. Friedrich may thus enable either the first locking part of the second locking part of the work tool to be independently attached to the coupler.

Unfortunately, Friedrich also requires additional actuators and associated hydraulic infrastructure to implement independent actuation of the securing element and the locking element, thereby increasing a cost and complexity of their design. In contrast, the single-actuator couplers of the prior art are much simpler in design and manufacture, but demand more complex maneuvers on the part of the work machine operator.

Accordingly, there remains a need in the art for a single-actuator quick coupler capable of independently and automatically locking onto a single tool pin of the work tool, thereby simplifying and safeguarding the coupling without unduly increasing the coupler's complexity and cost.

SUMMARY OF THE DISCLOSURE

According to a first aspect of the present disclosure, a quick coupler is disclosed. The quick coupler comprises a frame including: a notch defining a chamber and having a mouth, the notch configured to receive a first tool pin; and a hook defining a concavity and having an entrance, the hook configured to receive a second tool pin. The quick coupler further comprises a cylinder including a cap end and a rod end; a primary blocking member configured to lock and unlock the first tool pin within the notch, wherein the primary blocking member is attached to one of the cap end and the rod end of the cylinder; a secondary blocking member configured to lock and unlock the second tool pin within the hook, wherein the secondary blocking member is attached to the other of the cap end and the rod end of the cylinder; a biasing member biasing the secondary blocking member toward a locked position; and a controller. The quick coupler can automatically lock the second tool pin within the hook without actuating the cylinder.

According to a second aspect of the present disclosure, a method of coupling a work tool to a quick coupler is disclosed. The method comprises first activating an AUTOMATIC LOCKING state of the coupler. The method further comprises maneuvering the coupler to automatically lock a second tool pin of the work tool within a hook of the coupler without actuation of a cylinder of the coupler, such that: the second tool pin forces a secondary blocking member to move from a locked position to an unlocked position; the second tool pin enters the hook; and the secondary blocking member returns to the locked position. The method further comprises the first tool pin entering a notch of the coupler; and activating a LOCKED state of the coupler.

According to a third aspect of the present disclosure, a method of decoupling a work tool from a quick coupler is disclosed. The method comprises: activating an AUTOMATIC LOCKING state of the coupler. The method further comprises maneuvering the work tool to rest on a surface, during which, without actuating a cylinder of the coupler: a first tool pin exits a notch of the coupler; and a second tool pin is prevented from exiting a hook of the coupler. The method further comprises activating an UNLOCKED state of the coupler; and fully separating the coupler from the work tool.

These and other aspects and features of the present disclosure will be more readily understood after reading the following description in conjunction with the accompanying drawings.

DETAILED DESCRIPTION

Referring now to the drawings and with specific reference toFIG.1, a diagram of a work machine is generally referred to by a reference numeral1. While the work machine1is depicted as an excavator, it may alternatively be a mini-excavator, backhoe, front loader, tractor loader, or comparable machine employed in construction, mining, earth moving, and/or agricultural applications. The work machine1may specifically comprise a frame11, a prime mover12or engine supported by the frame11, and a locomotive device13supporting the frame11and being operatively driven by the prime mover12.

The work machine1may further include an implement arm20, including one or more of a boom, stick, dipper, and other possible appendages. The implement arm20may be operatively controlled by a hydraulic power system30, e.g. through one or more hydraulic actuators or cylinders. In the embodiment shown, the implement arm20may specifically include a boom21pivotably mounted at a proximal end to the frame11and operable by boom actuators31, which raise or lower the boom21with respect to the frame11. The implement arm20may further include a stick22pivotably connected at a proximal end to a distal end of the boom21and operable by stick actuators32, which pivot the stick22with respect to the boom21.

With continued reference toFIG.1, a quick coupler400may be connected to a distal end of the stick22and may be operable by one or more tool actuator33, which pivot the coupler400with respect to the stick22. More specifically, the coupler400may be pivotably connected to the stick22by a first stick pin221; and the tool actuator33may be operatively connected to the coupler400by a power link23coupled to a second stick pin222. In some embodiments, the quick coupler400may specifically be a pin grabber coupler400a, configured to associate with a pin-on work tool.

With continued reference toFIG.1, the quick coupler400may be configured to receive a work tool500, which may be operatively maneuvered by the implement arm20and the hydraulic power system30via the coupler400. In some embodiments, the work tool500may specifically be a pin-on work tool500a, configured to associate with the pin grabber coupler400a. And while the work tool500is illustrated as a bucket, this is by example only, and the tool500may alternatively be a grapple, hammer, compactor, claw, blade, or one of many other tools and attachments common to the art. Furthermore, in some embodiments, other configurations for the implement arm20and its appendages, and other methods of connecting and operating the quick coupler400, are also possible without departing from a scope of the present disclosure.

Turning now toFIG.2, a diagram of the quick coupler400is provided in greater detail. The quick coupler400may comprise a frame410, a cylinder420, a primary blocking member430, a secondary blocking member440, a biasing member450, and a controller (not shown). In some embodiments, the coupler400may further comprise a hydraulic assembly600. The frame410may include a pair of ports401, a notch411, and a hook412. The ports401may be configured to receive the first stick pin221and the second stick pin222of the work machine1. The notch411may have a mouth4111and may define a chamber4112. Further, the notch411may be configured to receive a first tool pin510of the work tool500. The hook412may have an entrance4121and define a concavity4122. Further, the hook may be configured to receive a second tool pin520of the work tool500.

The quick coupler400may further comprise a cylinder420having a cap end421and a rod end422. A primary blocking member430may be attached to either the cap end421or the rod end422of the cylinder420; and may be configured to lock and unlock the first tool pin510within the notch411of the frame410. A secondary blocking member440may be attached to the other of the cap end421and the rod end422(i.e. the end not attached to the primary blocking member430); and may be configured to lock and unlock the second tool pin520within the hook412of the frame410. While the primary blocking member430is shown to be attached to the rod end422and the secondary blocking member440is shown to be attached to the cap end421, in other embodiments these attachments can be reversed, i.e. the cylinder420can be reversed.

In an embodiment, the primary blocking member430may specifically include a wedge4301and a tab4302; and may be rotatably attached to an end of the cylinder420. In the exemplary embodiment shown inFIG.2, the wedge4301may be rotatably attached to the rod end422about a rotation axis W1; and the tab4302may be configured to lock and unlock the first tool pin510within the notch411. However, it should be understood that other configurations for the primary blocking member430are also possible. Without limitation, the primary blocking member430may alternatively or additionally include a rocker, a hook, a catch, and other possible locking mechanisms; the primary blocking member430may be connected to the cap end421of the cylinder420instead; and/or the primary blocking member430may include connections with the frame410.

In an embodiment, the secondary blocking member440may specifically include a rocker4401and a secondary lock4402; and may be rotatably attached to the other end of the cylinder420. In the exemplary embodiment shown inFIG.2, the rocker4401may be rotatably attached to the cap end421about a rotation axis R1 and pivotably attached to the frame410about a pivot axis R2. In the same or other embodiments, the secondary lock4402may be rotatably attached to the rocker4401about a rotation axis S1 and pivotably attached to the frame410about a pivot axis S2; and the secondary lock4402may be configured to lock and unlock the second tool pin520within the hook412. More specifically, a pivoting of the secondary lock4402may move the secondary blocking member440between a locked and unlocked position (and vice versa). However, it should be understood that other configurations for the secondary blocking member440are also possible. Without limitation, the secondary blocking member440may alternatively or additionally include a wedge, a tab, a hook, a catch, and other possible locking mechanisms; the secondary blocking member440may be connected to the rod end422of the cylinder420instead; and/or the secondary blocking member440may include alternative connections with the frame410.

With continued reference toFIG.2, the biasing member450may bias the secondary blocking member440toward the locked position. In the exemplary embodiment shown, the biasing member450may be a spring450amounted to the frame410and configured to convey a biasing force on the rocker4401, although other biasing devices and designs are also possible.

The quick coupler400may be capable of operating in one of at least three states, including a LOCKED state, an UNLOCKED state, and an AUTOMATIC LOCKING state. Each state will now be discussed in greater detail, and may be best understood with reference toFIG.9E,FIG.9A, andFIGS.9B-9D, respectively.

During the LOCKED state, as best depicted inFIG.9E, the cylinder420may be partially or fully extended. Accordingly, the primary blocking member430may be in a locked position, and may prevent the first tool pin510from entering or exiting the notch411. In the exemplary embodiment shown, the primary blocking member430may include the wedge4301and the tab4302connected to the rod end422. Accordingly, the cylinder420may be extended such that the tab4302blocks the mouth4111of the notch411. Likewise, during the LOCKED state, the secondary blocking member440may be in the locked position, and may prevent the second tool pin520from entering or exiting the hook412. In the exemplary embodiment shown, the secondary blocking member440may include the rocker4401and the secondary lock4402connected to the cap end421. Accordingly, the cylinder420may be extended such that the rocker4401is pivoted counterclockwise (CCW) about the pivot axis R2, and the secondary lock4402is pivoted clockwise (CW) about the pivot axis S2 to block the entrance4121of the hook412. It should be understood that the directions of rotation (i.e. CW, CCW) are provided for clarity only, are made with respect to the reference frames depicted inFIGS.9A-9Eonly, and that other directions and rotations are possible in other reference frames.

During the UNLOCKED state, as best depicted inFIG.9A, the cylinder420may be partially or fully retracted. Accordingly, the primary blocking member430may be in an unlocked position, and may allow the first tool pin510to freely enter or exit the notch411. In the exemplary embodiment shown, the primary blocking member430may include the wedge4301and the tab4302connected to the rod end422. Accordingly, the cylinder420may be retracted such that the tab4302unblocks the mouth4111of the notch411. Likewise, during the UNLOCKED state, the secondary blocking member440may be in an unlocked position, and may allow the second tool pin520to freely enter or exit the hook412. In the exemplary embodiment shown, the secondary blocking member440may include the rocker4401and the secondary lock4402connected to the cap end421. Accordingly, the cylinder420may be retracted such that the rocker4401is pivoted CW about the pivot axis R2, and the secondary lock4402is pivoted CCW about the pivot axis S2 to unblock the entrance4121of the hook412.

Before describing the AUTOMATIC LOCKING state, the present disclosure may benefit from a brief discussion of the hydraulic assembly600. In various embodiments, the hydraulic assembly600may be placed within the coupler400, may be partially located within the coupler400(as seen inFIG.2), or may be located external to the coupler400, depending on specific applicational requirements. With reference now toFIG.3, the hydraulic assembly600may specifically include a directional control assembly610controllably connected to one or more of the cap end421, the rod end422, a pump601, and a tank602. The directional control assembly610may be capable of operating in a second position corresponding to and operatively enabling the LOCKED state of the coupler400, a third position corresponding to and operatively enabling the UNLOCKED state of the coupler400, and a float position corresponding to and operatively enabling the AUTOMATIC LOCKING state of the coupler. In the exemplary embodiment shown, the directional control assembly610may include a 4-way 3-position directional control valve610a. And in the same or other embodiments, the directional control valve610amay be solenoid-controlled. In other embodiments, the directional control assembly610may be alternatively configured, such as with a 4-way 4-position directional control valve, a 4-way 5-position directional control valve, two 4-way 2-position directional control valves, and yet other possible designs without departing from a scope of the present disclosure.

During the LOCKED state of the coupler400, the directional control assembly610may be operating in the second position. Accordingly, the pump601may be connected to the cap end421and the tank602may be connected to the rod end422, thereby effecting an extension of the cylinder420.

During the UNLOCKED state of the coupler400, the directional control assembly610may be operating in the third position. Accordingly, the pump601may be connected to the rod end422and the tank602may be connected to the cap end421, thereby effecting a retraction of the cylinder420.

During the AUTOMATIC LOCKING state of the coupler400, as best depicted inFIGS.9B-9D, the directional control assembly610may operate in the float position seen inFIG.3. Accordingly, the directional control assembly610may operatively connect the cap end421, the rod end422, and the tank602, thereby removing most if not all hydraulic pressure imparted on the cylinder420. Under such conditions, and barring external forces, the cylinder420may remain in a position similar to its position before the AUTOMATIC LOCKING state was activated; and the primary blocking member430and the secondary blocking member440may likewise remain in their prior positions.

However, during the AUTOMATIC LOCKING state, the biasing member450biases the secondary blocking member440, such that the secondary blocking member440is moved to the locked position. It may be understood that, while the biasing member450may provide a biasing force in all operating states of the coupler400, its force may be negated by hydraulic pressures during the LOCKED and UNLOCKED states. In an embodiment, the biasing member450may be a spring450aand the secondary blocking member may include the rocker4401and the secondary lock4402. Accordingly, the spring450amay bias the rocker4401to rotate CCW about the pivot axis R2, such that the secondary lock4402is pivoted CW about the pivot axis S2 to block the entrance4121of the hook412.

Furthermore, during the AUTOMATIC LOCKING state, the secondary blocking member440may allow the second tool pin520to enter the hook412if the biasing force of the biasing member450is overcome. In other words, an operator may force the secondary blocking member440open by moving the coupler400to forcibly receive the second tool pin520within the hook412. Once the second tool pin520enters the hook412, the secondary blocking member440may return to the locked position, and may prevent the second tool pin520from exiting the hook412. In other words, during the AUTOMATIC LOCKING state, the coupler400may be capable of automatically locking the second tool pin520within the hook412without any actuation of the cylinder420. In some embodiments, the secondary blocking member440may be configured such that no amount of force in an exiting direction can move the secondary blocking member440into the unlocked position.

During the AUTOMATIC LOCKING state, the primary blocking member430may retain its position prior to the coupler400entering the AUTOMATIC LOCKING state. For example, if the previous state was the UNLOCKED state, the primary blocking member430may remain in an unlocked position. In some embodiments, the UNLOCKED state may always precede the AUTOMATIC LOCKING state, such that the primary blocking member430is always in the unlocked position during the AUTOMATIC LOCKING state. And in yet other embodiments, the primary blocking member430may be in the unlocked position during the AUTOMATIC LOCKING state, regardless of a prior state of the coupler400.

With reference now toFIGS.3-6, several embodiments of the hydraulic assembly600will now be described in greater detail. As previously discussed, the assembly600may be partially or fully located inside the coupler400. For the purposes of this disclosure, the terms ‘downstream’ and ‘upstream’ may refer to a directionality of each component, i.e. a check valve may only allow fluid flow in the ‘downstream’ direction.

As seen inFIG.3, the hydraulic assembly600may comprise the directional control assembly610operatively connected to the cap end421, the rod end422, the pump601, and the tank602. In an embodiment, the directional control assembly610may specifically include the 4-way 3-position directional control valve610a. In addition, the hydraulic assembly600may comprise a first check valve620, which may be a spring check valve, located downstream of the pump601and upstream of the directional control assembly610. In an embodiment, a flow control element630, which may be a fixed orifice, may be located between the first check valve620and upstream of the directional control assembly610. The assembly600may further comprise a first pilot-operated (PO) check valve640downstream of the directional control assembly610and upstream of the cap end421. In some embodiments, the hydraulic assembly600shown inFIG.3may be adequate to implement automatic locking mechanisms for a pin grabber coupler styled quick coupler.

Turning now toFIG.4, another embodiment of the hydraulic assembly600is shown. Specifically, the hydraulic assembly600may comprise at least the elements shown inFIG.3, and may further comprise a second PO check valve650, located downstream of the rod end422, upstream of the directional control assembly610, and receiving a pilot pressure from the cap end421. The assembly600may further comprise a pressure relief valve680located downstream of the rod end422, upstream of the directional control assembly610, and connected in parallel with the second PO check valve650. In some embodiments, the second PO check valve650may a prevent momentary bleeding of pressure from the rod end422of the cylinder420during transitions of the directional control assembly610. And in some embodiments, the hydraulic assembly600shown inFIG.4may be adequate to implement automatic locking mechanisms for a pin grabber coupler styled quick coupler.

Turning now toFIG.5, another embodiment of the hydraulic assembly600is shown. Specifically, the hydraulic assembly600may comprise at least the elements shown inFIG.3. Moreover, the assembly600may comprise a pressure reducing valve660downstream of the directional control assembly610and upstream of the rod end422; and and a second check valve670, which may be a spring check valve, downstream of the rod end422, upstream of the directional control assembly610, and connected in parallel with the pressure reducing valve660. In some embodiments, the hydraulic assembly600shown inFIG.5may be adequate to implement an automatic locking mechanism for any style of quick coupler.

Turning now toFIG.6, yet another possible embodiment of the hydraulic assembly600is provided. The assembly600may comprise at least the elements shown inFIG.5. Moreover, the assembly600may further comprise the second PO check valve650located downstream of the pressure reducing valve660and upstream of the rod end422. Furthermore, the pressure relief valve680may be located downstream of the rod end422, upstream of the second check valve670, and connected in parallel with the second PO check valve650. In some embodiments, the hydraulic assembly600shown inFIG.6may be adequate to implement an automatic locking mechanism for any style of quick coupler.

In some embodiments, the pressure relief valve680may prevent the primary blocking member430from inadvertently drifting when the directional control assembly610is operating in the float position, i.e. when the coupler400is in the AUTOMATIC LOCKING state. More specifically, when transitioning between the LOCKED state and the AUTOMATIC LOCKING state, the pressure relief valve680may be configured to allow a pressure release of the rod end422in order to prevent the primary blocking member430from drifting into the locked position, but nonetheless allowing the biasing member450to bias the secondary blocking member440into the locked position.

In other embodiments, when transitioning between the LOCKED state and the AUTOMATIC LOCKING state, the primary blocking member430may be held in a prior position through a force of friction only, such as in the exemplary embodiments shown inFIGS.3and5. And in yet other embodiments, the primary blocking member430may be permitted to drift slightly away from a prior position during the AUTOMATIC LOCKING state, so long as the notch411remains unblocked.

The hydraulic assembly600may be managed by a controller (not shown), the controller having a processor and a memory in the form of a non-transitory computer-readable medium. The controller may be, without restriction, a gateway computer, a field-programmable gate array (FPGA), an application-specific integrated circuit ASIC), an engine control unit (ECU) of the work machine1, or comparable computing device capable of receiving inputs and outputting commands to the hydraulic assembly600. The controller may be in operative communication with an operator of the work machine1, and may receive commands from the operator through any number of input devices19of the work machine1, such as but not limited to buttons, dials, switches, pedals, knobs, touchscreens, and the like.

The controller may operatively control the state of the coupler400(e.g. LOCKED, UNLOCKED, or AUTOMATIC LOCKING) according to inputs received from the operator and/or from the input devices19. In one embodiment, the input devices19may include a coupler switch19a. And in the same or other embodiments, the coupler switch19amay include one or more of the following settings: ‘temporary unlock’, ‘permanent unlock’, ‘permanent lock’, and ‘automatic locking’, each of which will be discussed in greater detail below.

By employing the disclosed designs, a quick coupler may be improved with an automatic locking mechanism without requiring additional actuators, thereby improving an ease and security of a tool coupling process without increasing underlying costs.

INDUSTRIAL APPLICATION

The present disclosure may find industrial applicability in any number of work machines which employ quick couplers in order to switch between different tool attachments. While the work machine is depicted as an excavator in certain embodiments, the present disclosure may likewise apply to mini-excavators, backhoes, front-end loaders, forest machines, material handlers, and other, comparable vehicles and machinery employed in construction, mining, earth moving, and/or agricultural applications. Furthermore, while the work tool is depicted as a bucket in certain embodiments, the quick coupler may be configured to attach to one of any number of work tools, including but not limited to augers, blades, bale grabs, compactors, forks, hammers, grapples, pulverizers, rippers, and many others. Moreover, the coupler may be capable of interlocking with work machines and with work tools from different manufacturers and product lines.

By employing the designs disclosed herein, a quick coupler may automatically lock onto a single tool pin of a work tool, decreasing an overall difficulty and improving an overall safety of the tool attachment process. More specifically, the automatic locking mechanism of the coupler may enable an operator to ‘grab’ a work tool situated at closer and/or further distances with respect to the work machine, situated at lower and/or higher elevations with respect to the work machine, and situated in a greater range of angles with respect to the tool's center of gravity or tool pin orientation. Once the first (or second) tool pin is secured, the automatic locking feature may decrease if not eliminate the possibility of detachment between the coupler and the work tool during the subsequent coupling maneuvers, making the process easier and safer for both equipment and personnel. Furthermore, when decoupling the work tool from the quick coupler, the same advantages with regard to operator ease, procedure safety, and machine range of motion may be afforded.

The above improvements may be obtained without increasing a complexity or cost of the coupler. More specifically, the quick coupler of the present disclosure can enable automatic locking and, indeed, independent locking of the second tool pin, with only a single hydraulic cylinder controlling both locking zones, i.e. the notch and the hook. Advantageously, in some embodiments, an existing quick coupler may be retrofitted with the disclosed designs through minor modifications to its hydraulic assembly and/or modifications to a logic controlling the hydraulic assembly.

Turning now toFIG.7, a method of coupling a work tool to a quick coupler is generally referred to by a reference numeral700. The method700may best understood in consideration ofFIGS.9A-9EandFIGS.10A-10D, the former depicting an operation of the coupler and the latter illustrating an operation of the hydraulic assembly throughout the coupling process. The method700may comprise activating an AUTOMATIC LOCKING state of the coupler (block701), maneuvering the coupler to automatically lock a second tool pin within a hook of the coupler (block702), the first tool pin entering a notch of the coupler (block703), and activating a LOCKED state of the coupler (block704), each step of which will be discussed in greater detail below.

The method may comprise first activating an AUTOMATIC LOCKING state of the coupler (block701). In some embodiments, the AUTOMATIC LOCKING state may be activated by operating a coupler switch, which may be located on the work machine1or located remotely. For example, the AUTOMATIC LOCKING state may be activated by switching the coupler switch to an ‘automatic locking’ setting.

In other embodiments, the AUTOMATIC LOCKING state may be activated if/when the operator executes a specific order of actions. For example, the AUTOMATIC LOCKING state may be activated if and/or only if the operator first curls the coupler, and switches the coupler switch to a ‘temporary unlock’ setting, thereby first activating an UNLOCKED state of the coupler. In such embodiments, an onboard computer of the work machine, the controller of the coupler, or another system may detect the order of actions, which effectively command the coupler to activate the AUTOMATIC LOCKING state. In other embodiments, alternative switches, inputs, and series of actions may be programmed to activate the AUTOMATIC LOCKING state, where no limitation is intended herein. Finally, in the same or other embodiments, the coupler may always enter the UNLOCKED state before activating the AUTOMATIC LOCKING state.

During the UNLOCKED state, a directional control assembly may operate in a third position operatively connecting a rod end of the cylinder to a pump and a cap end of the cylinder to a tank, as best seen inFIG.10A. The cylinder may retract such that both the primary blocking member and the secondary blocking member move to an unlocked position, as best seen inFIG.9A. At the same time, a biasing member may bias the secondary blocking member toward a locked position. However, when the coupler is in the UNLOCKED state, the force applied by the biasing member may be negated by the cylinder's hydraulic pressure.

After a predetermined period in the UNLOCKED state, such as a time require to fully retract the cylinder, the coupler may enter the AUTOMATIC LOCKING state. Accordingly, the directional control assembly may operate in a float position operatively connecting the rod end and the cap end to the tank, as best seen inFIG.10B. This may reduce hydraulic pressure to the cylinder, such that the biasing force of the spring is no longer negated. The secondary blocking member may thus be biased by the biasing member to move to the locked position, while the primary blocking member may remain in the unlocked position, as best seen inFIG.9B.

Returning now toFIG.7, the method700may comprise an operator maneuvering the coupler to automatically lock the second tool pin within the hook (block702). More specifically, the coupler may be maneuvered such that second tool pin forces the secondary blocking member to move from the locked position into the unlocked position; such that the second tool pin enters the hook; and such that the secondary blocking member returns to the locked position. In an exemplary embodiment seen inFIG.9C, the second tool pin may exert an entry force against a secondary lock rotatably attached to a rocker, and may rotate the secondary lock to force the secondary blocking member from the locked position to the unlocked position. Once the second tool pin enters the hook, the biasing member may return the secondary blocking member to the locked position. In some embodiments, the coupler may be configured such that no amount of exit force exerted by the second tool pin can move the secondary blocking member from the locked state into the unlocked state. Furthermore, throughout block702of the method700, the directional control assembly may continue to operate in the float position, as seen in FIG.10B. Accordingly, automatically locking the second tool pin within the hook may occur without any actuation of the cylinder.

With reference again toFIG.7, the method700may further comprise the first tool pin entering a notch of the coupler (block703). In some embodiments, this step may entail an operator lifting the work tool off a surface and curling the coupler, i.e. pivoting the coupler with respect to an implement arm of the work machine. As the work tool is raised from the surface, it may lose any normal forces exerted by the surface and may hang from the hook of the coupler by the second tool pin. Furthermore, as the coupler is curled, the coupler may rotate with respect to the work tool about a rotation axis T1 of the second tool pin, while an orientation of the work tool may stay relatively unchanged due to gravity. As best seen inFIG.9D, the coupler may be rotated with respect to the work tool such that the first tool pin freely enters the notch. Moreover, throughout block703, the directional control assembly may continue to operate in the float position, as seen inFIG.10C, again without any additional actuation of the cylinder.

Returning once again toFIG.7, the method700may finally comprise activating a LOCKED state of the quick coupler (block704). In some embodiments, the LOCKED state may be activated by operating the coupler switch, e.g. by switching to a ‘permanent lock’ setting. In the same or other embodiments, when the LOCKED state is activated, the directional control assembly may operate in the second position connecting the cap end of the cylinder to the pump and the rod end of the cylinder to the tank, as best seen inFIG.10D. Accordingly, the cylinder may partially or fully extend such that both the primary blocking member and the secondary blocking member move to the locked position, as best seen inFIG.9E. Accordingly, both the first tool pin and the second tool pin of the work tool may be securely attached to the coupler, thereby completing the coupling process.

It may be appreciated that in some or all of the above embodiments, each step of method700may be operatively performed by an operator of the work machine.

Turning now toFIG.8, a method of decoupling a work tool from a quick coupler is generally referred to by a reference numeral800. The method800may best be understood in consideration ofFIGS.11A-11EandFIGS.12A-12D, the former depicting an operation of the coupler and the latter illustrating an operation of the hydraulic assembly throughout the process. The method800may comprise activating an AUTOMATIC LOCKING state of the coupler (block801), maneuvering the work tool to rest on a surface (block802), activating an UNLOCKED state of the coupler (block803), and fully separating the coupler from the work tool (block804), each step of which will be discussed in greater detail below. Note that the method800assumes a starting configuration wherein the work tool is attached to the coupler, as seen inFIG.11A.

The method may comprise first activating an AUTOMATIC LOCKING state of the quick coupler (block801). In some embodiments, the AUTOMATIC LOCKING state may be activated by operating a coupler switch, for example by switching the coupler switch to an ‘automatic locking’ setting.

In other embodiments, the AUTOMATIC LOCKING state may be activated if/when the operator executes a specific order of actions. For example, the AUTOMATIC LOCKING state may be activated if and/or only if the operator first curls the coupler, and switches the coupler switch to a ‘temporary unlock’ setting, thereby first activating an UNLOCKED state of the coupler. In such embodiments, an onboard computer of the work machine, the controller of the coupler, or another system may detect the order of actions, which effectively command the coupler to activate the AUTOMATIC LOCKING state.

During the UNLOCKED state, a directional control assembly may operate in a third position connecting a rod end of the cylinder to a pump and a cap end of the cylinder to a tank, as best seen inFIG.12A. Accordingly, the cylinder may retract such that both the primary blocking member and the secondary blocking member move to an unlocked position, as best seen inFIG.11B. At the same time, a biasing member may bias the secondary blocking member toward a locked position. However, when the coupler is in the UNLOCKED state, the force applied by the biasing member may be negated by the cylinder's hydraulic pressure.

After a predetermined period in the UNLOCKED state, such as a time require to fully retract the cylinder, the coupler may enter the AUTOMATIC LOCKING state. The directional control assembly may operate in a float position connecting the rod end and the cap end to the tank, as best seen inFIG.12B. This may reduce hydraulic pressure to the cylinder, such that the biasing force of the spring is no longer negated. The secondary blocking member may thus be biased by the biasing member to move to the locked position, while the primary blocking member may remain in the unlocked position, as best seen inFIG.11C.

Returning now toFIG.8, the method800may comprise the operator maneuvering the work machine to move the work tool to rest on a surface (block802). In some embodiments, the work tool may be attached to the coupler only by the second tool pin, which is hanging from the hook of the coupler and prevented from exiting said hook by the secondary blocking member, as best seen inFIG.11C. And as previously discussed, the coupler may be configured such that no amount of exit force exerted by the second tool pin can move the secondary blocking member away from the locked. Meanwhile, the first tool pin of the work tool may freely exit the notch of the coupler. More specifically, as the operator maneuvers the work tool, the coupler may rotate with respect to the work tool about the rotation axis T1 of the second tool pin, such that the first tool pin freely exits the notch. Furthermore, throughout block802, the directional control assembly may continue to operate in the float position, as seen inFIG.12C. Accordingly, manipulation of the work tool during block802may occur without any actuation of the cylinder.

With continued reference toFIG.8, the method800may finally comprise activating the UNLOCKED state of the coupler (block803). In some embodiments, the UNLOCKED state may be activated by operating the coupler switch, e.g. by switching to a ‘permanent unlock’ setting. The ‘permanent unlock’ setting may differ from the ‘temporary unlock’ setting in that it is not followed by the AUTOMATIC LOCKING state. In the same or other embodiments, when the UNLOCKED state is activated, the directional control assembly may operate in the third position connecting the rod end of the cylinder to the pump and connecting the cap end to the tank, as best seen inFIG.12D. Accordingly, the cylinder may retract such that the primary blocking member remains in the unlocked position, and such that the secondary blocking member moves to the unlocked position, as best seen inFIG.11D. While the biasing member may still provide a biasing force on the secondary blocking member, said force may be negated by the cylinder's hydraulic pressure.

In the UNLOCKED state, the first tool pin may freely exit the notch if it has not already done so. Moreover, the second tool pin may freely exit the hook. Thus, in a final step of method800, the operator may fully separate the coupler from the work tool (block804), as seen inFIG.11E. Since the two components are not longer interlocked, the operator may simply maneuver the work machine to physically move the coupler away from the tool, thereby completing the decoupling process.

It may be appreciated that in some or all of the above embodiments, each step of the method800may be operatively performed by an operator of the work machine.