The present invention relates to improvements to couplers, and more particularly, to couplers used to secure work attachments to work vehicles.
Couplers are devices used to secure work attachments to work vehicles. These devices generally function through the coupler having a plurality of jaws to engage a pair of pins on the work attachment.
There are many configurations for the jaws used in available couplers. For instance, some couplers include a single fixed jaw, used in combination with either a sliding jaw or a pivoting jaw (hook). Alternatively, a coupler may include a pair of fixed jaws, at least one of which includes a secondary (moveable) jaw or locking portion to secure the work attachment's pins in the immoveable jaw(s).
Work vehicles such as diggers and their work attachments are frequently used in the construction industry. The use of this type of equipment creates health and safety risks. Therefore, it is important to ensure that the work attachments are securely connected to the work vehicle. In fact, many countries have regulations that couplers must include locking mechanisms to secure a pin in the coupler's jaw(s).
Many of the available couplers have configurations that could potentially cause the coupler to be in an unsafe position for use e.g. one of the jaws or locking portions do not adequately engage the pin(s). This can lead to inadvertent release of the pins, and thereby dropping of the work attachment. Obviously, this will create health and safety risks and should be minimized or reduced.
United States Patent Application Publication No. 2013/0164080 to Miller describes a coupler having a trigger to activate a locking mechanism when the coupler body is brought into alignment/contact with the work attachment's pin. Once activated, the locking mechanism is moved by actuators into a position in which it secures a pin in a jaw of the coupler. This coupler includes a locking member which is pivotally secured to the coupler body. That locking member, when engaged, secures a pin in an immoveable jaw of the coupler body.
The locking member is positioned above the moveable jaw and below a quick connect that secures the coupler to a work vehicle. As the locking member needs to pivot to move between release position and a lock position, it requires a large space between the immoveable jaw and the quick connect. That space accentuates the coupler's vertical offset. Increasing a coupler's vertical offset increases the tip radius for a work attachment such as a bucket. The tip diameter is related to the power which a work vehicle can transfer to the work attachment. Increasing tip diameter decreases the effective power of the work attachment in use. Therefore, decreasing vertical offset would be beneficial.
However, the configuration of the locking member used in United States Patent Application Publication No. 2013/0164080 does not enable the vertical offset to be minimized. As a result, this coupler does not provide a completely satisfactory solution to the problems experienced with existing couplers.
Another problem of the coupler described in United States Patent Application Publication No. 2013/0164080 arises from the use of two separate locking members. Engagement of the trigger causes the locking members to be released, so that actuators such as springs can move those locking members to a position in which they engage the work attachment's pins. However, there are several moving parts. This increases the complexity of the coupler from the design and manufacturing perspective. In addition, these additional moving parts are a potential source of wear and failure for the coupler.
As a result, it would be beneficial to have a coupler having fewer moving parts than that described in United States Patent Application Publication No. 2013/0164080, yet that activates locking portions when a pin is brought into a predetermined position with respect to the coupler.
It would also be beneficial to have a coupler which could reduce the vertical offset while activating locking portions when a pin is moved into a predetermined position with respect to the coupler.
In addition, it would be an advantage to provide the public with an improved coupler that addresses any or all of the foregoing problems.
Alternatively, it is objective of the present invention to provide the public with a useful choice.
Certain embodiments of the present invention may provide solutions to the problems and needs in the art that have not yet been fully identified, appreciated, or solved by current coupler technologies. For example, some embodiments of the present invention pertain to a coupler to secure a work attachment to a work vehicle. The work attachment includes a first pin and a second pin. The coupler includes a coupler body having a first engagement portion that is configured to accept the first pin, a second engagement portion configured to accept the second pin, and a guide. The coupler also includes a slider configured to slide along the guide. A body of the slider includes a first locking portion and a second locking portion. The coupler further includes a trigger located on the coupler body such that the trigger is released by contact with the second pin and a first actuator that is activated by release of the trigger. When the trigger is released, the first actuator can move the slider along the guide into an engaged position where the first locking portion engages and retains the first pin in the first engagement portion of the coupler body, and the second locking portion engages and retains the second pin in the second engagement portion of the coupler body, at the same time.
In some embodiments the first engagement portion and the second engagement portion are located at fixed positions on the coupler body and are spaced apart by a fixed distance. In certain embodiments, the locking portion and the second locking portion are located at fixed positions on the slider body and are spaced apart by the fixed distance. In some embodiments, the fixed distance corresponds to a separation between the first pin and the second pin of the work attachment. In certain embodiments, the first actuator is a coil spring. In some embodiments, the coupler includes a locking mechanism configured to hold the slider in a disengaged position, in which the first pin is not retained in the first engagement portion and the second pin is not retained in the second engagement portion, until the trigger is released.
According to some embodiments of the present invention, there is provided a coupler substantially as described above including a second actuator that, when activated, is configured to move the slider from the engaged position to the disengaged position. In some embodiments, activation of the second activator to move the slider into the disengaged position includes resetting the trigger. In certain embodiments, the second actuator is a hydraulically operated actuator.
According to some embodiments of the present invention, there is provided a method of securing a work attachment to a work vehicle. The work attachment includes a first pin and a second pin, and the coupler includes a coupler body having a first engagement portion that is configured to accept the first pin, a second engagement portion configured to accept the second pin, and a guide. The coupler also includes a slider configured to slide along the guide. A body of the slider includes a first locking portion and a second locking portion. The coupler further includes a trigger located on the coupler body such that the trigger is released by contact with the second pin and a first actuator that is activated by release of the trigger. The method includes locating the first pin on the work attachment in the first engagement portion of the coupler body and inserting the second pin into the second engagement portion of the coupler body so that the second pin contacts and releases the trigger. The method also includes activating the first actuator to move the slider along the guide into an engaged position where the first locking portion engages and retains the first pin in the first engagement portion of the coupler body, and the second locking portion engages and retains the second pin in the second engagement portion of the coupler body, at the same time.
In some embodiments, the method includes releasing the work attachment from the coupler by moving the slider with respect to the coupler body into a disengaged position in which the first pin is not retained in the first engagement portion and the second pin is not retained in the second engagement portion. In certain embodiments, the slider is moved manually. In other embodiments, the slider is moved by action of a second activator. In some embodiments, the step of moving the slider into the disengaged position includes resetting the trigger.
Throughout the present specification reference to the term slider should be understood meaning a component that is configured to move with a sliding motion with respect to the coupler body.
The coupler including a slider provides a number of benefits. For instance, the slider requires a comparatively smaller cavity in the coupler body to provide it with the necessary range of motion than a pivoting hook. Therefore, the slider enables the coupler's vertical offset to be minimized compared to different types of couplers.
In addition, the slider is able to provide two locking portions that can each engage a pin on a work attachment, e.g., a different pin to the other. This is due to the range of motion of the slider. In contrast, using a hook style coupler requires several separate components to be used to engage two separate pins. That increases the complexity of the hook style couplers. It also means that hook style couplers include more parts to the present invention which increases manufacturing costs, and may reduce the reliability of the coupler. Therefore, the use of a slider assists in reducing the moving parts in the coupler.
Throughout the present specification reference to the term “locking portion” should be understood as meaning a component to engage a pin of a work attachment.
Engagement of the pin can occur in a number of different ways. For instance, a locking portion may have a substantially “c” shaped cross section. Therefore, in use, the locking portion surrounds a substantial portion of a pin.
Alternatively, the locking portion may be a detent secured to the slider, or an end of the slider. In use, these embodiments abut the pin, and also decrease the opening of a fixed jaw in the coupler. The interaction of the locking portion with the pin and fixed jaw secures the pin to the coupler.
However, the foregoing should not be seen as limiting on the scope of the present invention. It is also envisaged that the locking portion could take alternative forms. For instance, a locking portion may be provided by a pair of movable jaws which both engage the same pin. In these embodiments the interaction of the two moveable jaws secures the pin with respect to the coupler.
Throughout the present specification reference to the term “trigger” should be understood as meaning a component which when engaged enables an actuator to move the locking portions to a locking position.
In preferred embodiments, the trigger is configured to move a locking mechanism so that it releases the locking portion(s) to thereby allow them to be moved by an actuator.
The use of a trigger may assist in providing a coupler that automatically moves two locking portions to an engaged position when the coupler engages with the second pin, without operator involvement.
Throughout the present specification reference will be made to the terms disengaged position and engaged position.
The term “disengaged position” should be understood as meaning a position in which a locking portion does not engage a pin on a work attachment. It should be appreciated that the term does not refer to the position of the coupler body with respect to a work attachment. Rather, the term refers to the position of the locking portion(s) with respect to the coupler body, and in which the coupler can move with respect to the pins.
In some embodiments, the locking portions are moved by an actuator such as a spring. However, the actuator may take other forms such as being a worm drive, hydraulic actuator, or chain drive mechanism. Therefore, the foregoing should not be seen as limiting.
In some embodiments, the coupler is configured so that the locking portions are manually moved to a disengaged position. For instance, a person can apply force to the slider so as to cause it to move with respect to the coupler body.
The actuator in some embodiments may be a hydraulic cylinder or other suitable component as would be known to one skilled in the art. As a result, the foregoing should not be seen as limiting on the scope of the present invention.
Some embodiments include a locking mechanism.
Throughout the present specification reference to the term “locking mechanism” should be understood as meaning a component to limit, and preferably prevent movement of, the locking portion(s).
In some embodiments, the locking mechanism secures the locking portions in the disengaged and/or engaged positions. Therefore, the locking mechanism prevents the locking portions inadvertently disengaging the pin(s).
In addition, the locking mechanism can hold the locking portions in a disengaged position. This enables a trigger to be used to release the locking portions on engagement by a pin of a work attachment.
However, the foregoing should not be seen as limiting on the scope of the present invention. For instance, it is also envisaged that the locking mechanism could be provided by check valves that restrict expansion or contraction of a hydraulic cylinder which is configured to move the locking portions.
It should be appreciated that the present invention may have a number of advantages. These include, but are not limited to, automatically causing a locking portion(s) to be moved to an engaged position to thereby secure a work attachment to the coupler without operator involvement. This reduces the potential for a work attachment to be improperly connected to the coupler and thereby provides a potentially safer coupler. Also, the number of moving parts of the coupler may be reduced compared to those currently available. Accordingly, the coupler may be more cost effective to manufacture, easier to maintain, and less prone to failure. Further, the coupler's vertical offset may be reduced while achieving the above.
In order that the advantages of certain embodiments of the invention will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. While it should be understood that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:
Some embodiments pertain to couplers that automatically cause a locking portion(s) to be moved to an engaged position to thereby secure a work attachment to the coupler without operator involvement. This reduces the potential for a work attachment to be improperly connected to the coupler and thereby provides a potentially safer coupler. Also, the number of moving parts of the coupler may be reduced compared to conventional couplers. Accordingly, the coupler of some embodiments may be more cost effective to manufacture, easier to maintain, and less prone to failure. Further, the coupler's vertical offset may be reduced while activating locking portions when a pin is moved into a predetermined position with respect to the coupler.
Referring first to
The coupler body (2) includes a first engagement portion in the form of a first fixed jaw (9). The first fixed jaw (9) has a substantially “C” shaped cross-section as is best seen in
The coupler body also includes a second engagement portion in the form of a second fixed jaw (25). The second fixed jaw is in the form of a curved face on the underside of the coupler body. The opening of the first fixed jaw is directed towards the front of the coupler body while the opening of the second fixed jaw is directed towards the rear of the coupler body.
The coupler body (2) includes a guide in the form of channels (4). The channels (4) are configured to receive the side edges (6) of a slider, generally indicated by arrow (5) in
For clarity of description we will use the term “upper”, “lower”, “front” and “back”, and similar terms in relation to the coupler, where the terms are those that would normally be used to describe the orientation of the coupler as shown in the figures (with the front being to the right hand side).
The slider (5) includes a second locking portion in the form of a slider fixed jaw (8) that is substantially “C” shaped in cross-section. The opening of the slider fixed jaw is directed towards the front of the slider, so that the slider fixed jaw (8) forms a clamp with the second fixed jaw of the coupler body (25). The first locking portion (7) and the second locking portion (8) are located at fixed positions on the slider. Therefore, movement of the slider (5) with respect to the coupler body (2) does not alter the separation between the first and second locking portions (7, 8).
The slider includes a beam (26) which forms part of a locking mechanism. The beam has a cross section like a truncated rectangle; i.e. a rectangle with a cut made from a corner on one side to a point partially along the opposite side, the cut forming a ramp between the two sides. The beam is located across the slider body near the rear of the slider body, such that the shorter side of the rectangle is facing forwards.
A first actuator in the form of a spring (13) is connected at one end to an attachment portion (14) on the slider. The attachment portion (14) is pivotally secured to the slider (5) near the front end. The other end of the spring (13) is attached to a trigger (15) at a trigger attachment portion (50). The trigger (15) is pivotally mounted to the coupler body (2) by an axle (16) that extends from the edges of the trigger (15). The axle (16) sits within apertures (see, for example,
A trigger locking mechanism in the form of a member (18) extends away from the trigger's body (17). The trigger locking mechanism is configured to operate in conjunction with the beam (26). The locking member (18) includes a first portion (19) and a second portion (20). The second portion is in the form of a ledge extending downward from the locking member. In use the ledge (20) engages with the beam (26) to lock and/or unlock the slider with respect to the coupler body.
An underside (21) of the trigger's body (17) provides an engagement portion (21) which extends between the axle (16) and the second portion (20). An upward force applied to the engagement portion (21) causes the trigger's body (17) to rotate around the axle (16). This rotation lifts the ledge (20) up the longer rear side of the beam onto the ramp. This action releases the slider to move forward with respect to the coupler body. When the beam (26) has passed beneath the ledge (20) the rear side of the ledge drops down over the forward side of the beam into an indent, which may prevent the slider from moving and releasing the pins (until the locking mechanism is reset).
The slider (5) includes a hook (22). The hook (22) provides a point at which the slider (5) may be engaged so as to move that along the length of channels (4). In the embodiment shown in
Referring now to
The next step involves rotating the coupler body (2) so that the second pin (24) is bought into contact with the second engagement portion (25) on the underside of the coupler body (2). In doing so, the second pin (24) is bought into contact with the engagement portion (21) of the trigger's body (17). This causes the trigger (15) to pivot about the axle (16), thus moving the ledge (20) up the rear face of the beam (26) onto the ramp of the beam allowing the slider to move. This is illustrated in
The stored energy in the compressed spring (13) applies a force between the trigger attachment portion (50) (which is essentially fixed relative to the coupler body) and the attachment portion (14) at the front of the slider body. The force causes the slider (5) to move along the channels (4) towards the first fixed jaw (9) in the direction shown by arrow (27) in
The cradle (10) and the first locking portion (7) engage the first pin (23) to prevent movement with respect to the coupler body (22). Accordingly, the second pin (24) is not able to move longitudinally with respect to the channels (4). As a result, the second pin (24) does not exert a substantial or significant force having a horizontal component against the second locking portion (8). Therefore, the second pin (24) only exerts force having a vertical component against the second locking portion (8). This helps to reduce the chances that in operation the forces which the second pin (24) may exert against the coupler (1) could lead to the coupler (1) being moved to a release position.
The spring (13) exerts a force against the trigger (17) causing it to rotate about axle (17) in the direction shown by arrow (27) in
To release the work attachment an operator can engage engagement portion (19) of the locking mechanism to lift the ledge (20) above the beam (26), thus allowing the slider to be moved backwards, for example by pulling on the hook (22). Continued movement of the slider (5) along the channels (4) causes the first and second locking portions (7, 8) to disengage (release) the first and second pins (23, 24).
Referring now to
The second actuator (37) is in the form of a hydraulic cylinder including a housing (38) and ram (39). The hydraulic cylinder (37) is connected to a hydraulic control system (not shown in the Figures) as should be understood by one skilled in the art. The hydraulic cylinder (37) is located in the front portion of the slider.
Rods (40) extend from the side of the housing (38). The rods (40) are configured to sit within transverse channels (36) near the front end of the slider (32), so that the hydraulic cylinder can pivot about the rods (40).
The ram (39) includes a mounting (42) configured to connect the second actuator (37) to the trigger (30). The first actuator, in the form of a coil spring (43), is wound around the ram (39) between the housing (38) and the mounting (42). The hydraulic cylinder is configured to retract the ram into the cylinder when pressure is applied (i.e. shorten the distance between the hydraulic cylinder and the trigger). Hence the effective action of the coil spring is to exert a force against the trigger counteracting the force applied by the hydraulic cylinder as it retracts.
Pressure is applied to the hydraulic cylinder (37) when the coupler is to be operated to release the pins. The hydraulic cylinder is configured to retract the ram (39) into the cylinder body (38) when pressure is applied. This does several things: firstly it pulls the trigger (30) towards the front of the coupler body causing the trigger to rotate and release the locking mechanism from the beam (35) of the locking mechanism; secondly after the initial rotation of the trigger further retraction of the ram pulls the slider towards the trigger, thus moving the slider backwards with respect to the coupler body and into the release position in which the first locking portion (33) and a second locking portion (34) do not engage pins on a work attachment; and thirdly it compresses the coil spring, all as shown in
The hydraulic system is configured to release the pressure to the hydraulic cylinder when the slider reaches the full release position. This allows the coil spring (13) to push against the trigger (30), which is no longer pulled by the ram, thus initially causing the trigger to rotate towards the rear of the slide where it engages with the front face of the beam (35) of the locking mechanism, preventing further movement towards the rear.
The sequence of actions performed when the coupler is next used to move the slider into the engaged position is as described previously for the first embodiment. No pressure is applied to the hydraulic cylinder during the engagement process. A key feature again is that the trigger (30) is released by upward pressure on the trigger when the second pin is engaged in the second engagement portion of the coupler body.
The coupler (28) of this embodiment therefore includes a mechanism to cause automatic engagement of the first and second pins (23, 24) on the work attachment when a designated pin is bought into a position relative to the coupler body (29). Furthermore, the coupler (28) can subsequently be moved to a disengaged position through activation of the second actuator, thereby releasing the work attachment, without the operator exiting the work vehicle.
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
Throughout this specification, the word “comprise”, or variations thereof such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
It will be readily understood that the components of various embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the detailed description of the embodiments of the present invention, as represented in the attached figures, is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention.
The features, structures, or characteristics of the invention described throughout this specification may be combined in any suitable manner in one or more embodiments. For example, reference throughout this specification to “certain embodiments,” “some embodiments,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in certain embodiments,” “in some embodiment,” “in other embodiments,” or similar language throughout this specification do not necessarily all refer to the same group of embodiments and the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
It should be noted that reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussion of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment.
Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.
One having ordinary skill in the art will readily understand that the invention as discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, although the invention has been described based upon these preferred embodiments, it would be apparent to those of skill in the art that certain modifications, variations, and alternative constructions would be apparent, while remaining within the spirit and scope of the invention. In order to determine the metes and bounds of the invention, therefore, reference should be made to the appended claims.
Number | Date | Country | Kind |
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619300 | Dec 2013 | NZ | national |
This application is a U.S. national stage application under 35 U.S.C. §371 of PCT Application Number PCT/NZ2014/000246 filed on Dec. 17, 2014, which claims the benefit of New Zealand Patent Provisional Application Number 619300 filed on Dec. 24, 2013. The subject matter of these earlier filed patent applications is hereby incorporated by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/NZ2014/000246 | 12/17/2014 | WO | 00 |