AU2014370524A1

AU2014370524A1 - Improvements to couplers

Info

Publication number: AU2014370524A1
Application number: AU2014370524A
Authority: AU
Inventors: Jeremy Glen Doherty; Paul James Doherty
Original assignee: Doherty Engineered Attachments Ltd
Current assignee: Doherty Engineered Attachments Ltd
Priority date: 2013-12-24
Filing date: 2014-12-17
Publication date: 2016-08-04
Also published as: GB201612507D0; US20160319508A1; GB2541536A; GB2541536B; WO2015099543A1

Abstract

A coupler to secure a work attachment to a work vehicle is disclosed. The work attachment includes a first pin and a second pin, while the coupler body has a first engagement portion which is configured to accept the first pin and a second engagement portion configured to accept the second pin. The coupler body has a guide and a slider configured to slide along the guide. The body of the slider includes a first locking portion and a second locking portion. The coupler has 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 moves 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.

Description

IMPROVEMENTS TO COUPLERS TECHNICAL FIELD

The present invention relates to improvements to couplers and particularly to couplers used to secure work attachments to work vehicles.

BACKGROUND ART

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 countless 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 minimised or reduced.

United States Patent Publication No. 20130164080 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 Publication No. 20130164080 does not enable the vertical offset to be minimised. 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 Publication No. 20130164080 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. There are though 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 Publication No. 20130164080, yet 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.

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.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

DISCLOSURE OF THE INVENTION

According to one aspect of the present invention there is provided a coupler to secure a work attachment to a work vehicle, wherein the work attachment includes a first pin and a second pin, the coupler including: a coupler body having a first engagement portion which is configured to accept the first pin, a second engagement portion configured to accept the second pin, and a guide; a slider configured to slide along the guide, wherein a body of the slider includes a first locking portion and a second locking portion; 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, wherein 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 a preferred embodiment 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 a preferred embodiment 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 a preferred embodiment the fixed distance corresponds to a separation between the first pin and the second pin of the work attachment.

In a preferred embodiment the first actuator is a coil spring.

In a preferred embodiment 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 another aspect of the present invention there is provided a coupler substantially as described above including a second actuator which, when activated, is configured to move the slider from the engaged position to the disengaged position.

In a preferred embodiment activation of the second activator to move the slider into the disengaged position includes resetting the trigger.

In a preferred embodiment the second actuator is an hydraulically operated actuator.

According to another aspect of the present invention, there is provided a method of securing a work attachment to a work vehicle, wherein the work attachment includes a first pin and a second pin, and wherein the coupler includes: a coupler body having a first engagement portion which is configured to accept the first pin, a second engagement portion configured to accept the second pin, and a guide; a slider configured to slide along the guide, wherein a body of the slider includes a first locking portion and a second locking portion; 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 including the steps of: a) locating the first pin on the work attachment in the first engagement portion of the coupler body; b) inserting the second pin into the second engagement portion of the coupler body so that the second pin contacts and releases the trigger; c) 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 a preferred embodiment the method includes the step of: d) 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 a preferred embodiment the slider is moved manually.

In other embodiments the slider is moved by action of a second activator.

In a preferred embodiment 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 which 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 a preferred embodiment, 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.

In a preferred embodiment the present invention includes 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 a preferred embodiment 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, such as: • Automatically causes 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. • Reduces the number of moving parts of the coupler compared to those currently available. Accordingly the coupler may be more cost effective to manufacture, easier to maintain, and less prone to failure. • Reduces the coupler’s vertical offset while achieving the above.

BRIEF DESCRIPTION OF DRAWINGS

Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which:

Figure 1 is a side perspective exploded view of a coupler according to one embodiment of present invention;

Figure 2 is a front view of an assembled coupler according to a first embodiment of the present invention;

Figure 3 is a top view of Figure 2;

Figure 4 is a perspective view of Figures 2 and 3;

Figure 5 is a side view of Figures 2-4;

Figures 6D are side cross-sectional schematics showing the process of securing a work attachment to a vehicle using a coupler according to the first embodiment of the present invention;

Figure 7 is an exploded perspective of a second embodiment of a coupler according to the present invention;

Figure 8 is a side view of a coupler according to the second embodiment of the present invention;

Figure 9 is a top view of Figure 8;

Figure 10 is a side-cross sectional view of a coupler according to the second embodiment of the present invention in a locked position;

Figure 11 a view of Figure 11 in a release position.

BEST MODES FOR CARRYING OUT THE INVENTION

Referring first to Figure 1, there is provided a coupler (1) according to a first embodiment of the present invention.

The coupler (1) includes a coupler body (2).

The coupler body (2) includes apertures (3) forming part of a quick connect configured to secure the coupler (1) to an arm of a work vehicle (not shown in the Figures).

The apertures (3) and quick connect (not shown) are as should be known to one skilled in the art.

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 Figure 5.

The first fixed jaw (9) includes a cradle section (10) and a lip (11). The linear (shortest) distance between a first edge of cradle (10A) and a second edge of cradle (10B) is sufficient to enable a first pin (12) on a work attachment (not shown in the Figures) to be inserted into the jaw (9).

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 Fig. 1.

Interaction between the channels (4) and the side edges (6) of the slider (5) defines a path of movement for the slider (5) with respect to the coupler body (2).

The slider (5) provides a first locking portion (7). In the embodiment shown in the Figures, the first locking portion is provided by a surface on an underside of a front end of the slider. Preferably the surface is flat.

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 Fig. 6B) in the coupler body (2) so as to pivotally secure the trigger (15) to the coupler body (2). 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 Figures 1 - 5, the hook (22) is orientated to extend in an upwards direction in the coupler (1) normal orientation in use of the coupler (1). However, the hook (22) can take other shapes and/or orientations.

Referring now to Figures 6A - 6D, showing the steps involved in using the coupler (1) to secure a work attachment (not shown) to a work vehicle (not shown). The work attachment includes a first pin (23) and a second pin (24) as should be known to one skilled in the art.

Initially the work vehicle is used to manoeuver the coupler (1) so that the first pin (23) is inserted into the immovable jaw (9) (i.e. the first engagement portion). At this stage the coupler body is typically inclined with respect to the two pins of the work attachment, as shown in Fig. 6A, so that only the first pin is engaged with the coupler.

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 Fig. 6B.

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 Figure 6C.

The spring (13) moves the slider (5) into the position shown in Figure 6D. In doing so, the first locking portion (7) is bought into a position in which it engages the first pin (23). The first locking portion (7) reduces the opening of the jaw (9) to thereby secure the first pin (23) in the jaw (9).

At the same time the second locking portion (8) is moved to engage the second pin (24) against the second fixed jaw (25).

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 Figure 6D. This causes the ledge (20) to bear against the front side of the beam (26). As a result, the locking mechanism prevents the slider (5) moving backwards, which could disengage (release) the first pin (23) and the second pin (24). This is an engaged (locked) position for the coupler (1). The locking portions (7, 8) have engaged the first and second pins (23, 24). In addition, the locking mechanism (20, 26) may reduce or prevent movement of the slider (5).

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 Figures 7, 8, 9, 10, and 11 which show a coupler (28) which is similar to that described above (and in Figures 1-6),but including a second activator configured to move the slider back into the disengaged position, in the process compressing the coil spring and resetting the trigger

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.

Figures 9 and 10 show this embodiment of the coupler in the engaged position. The trigger (30) is held against the rear face of the locking mechanism preventing forward movement of the slider under the action of the coil spring (13). In this position there is no pressure applied to the hydraulic cylinder.

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 Fig. 11. This series of actions releases the pins and resets the coil spring ready for re-engagement with the pins.

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.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.

Claims

WHAT WE CLAIM I:

1. A coupler to secure a work attachment to a work vehicle, wherein the work attachment includes a first pin and a second pin, the coupler including: a coupler body having a first engagement portion which is configured to accept the first pin, a second engagement portion configured to accept the second pin, and a guide; a slider configured to slide along the guide, wherein a body of the slider includes a first locking portion and a second locking portion; 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, wherein 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.
2. A coupler as claimed in claim 1 wherein 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.
3. A coupler as claimed in claim 2 wherein the first engagement portion and the second engagement portion are located at fixed positions on the slider body spaced apart by the fixed distance.
4. A coupler as claimed in either one of claims 2 or 3 wherein the fixed distance corresponds to a separation between the first pin and the second pin of the work attachment.
5. A coupler as claimed in any one of claims 1 to 4 wherein the first engagement portion is a first fixed jaw.
6. A coupler as claimed in any one of claims 1 to 5 wherein the second engagement portion is a second fixed jaw.
7. A coupler as claimed in any one of claims 1 to 6 wherein the first locking portion of the slider is an end of the slider that enters into the space created by the first fixed jaw of the coupler body.
8. A coupler as claimed in any one of claims 1 to 7 wherein the second locking portion of the slider is a third fixed jaw.
9. A coupler as claimed in any one of claims 1 to 8 including 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.
10. A coupler as claimed in any one of claims 1 to 9 wherein the trigger is configured to operate the locking mechanism so that, when the trigger is released, it releases the slider allowing it to be moved by the first actuator into the engaged position.
11. A coupler as claimed in either one of claims 9 or 10 wherein the slider is moved to the disengaged position manually.
12. A coupler as claimed in any one of claims 1 to 11 wherein the first actuator is a coil spring.
13. A coupler as claimed in any one of claims 9 to 12 including a second actuator which, when activated, is configured to move the slider from the engaged position to the disengaged position.
14. A coupler as claimed in claim 13 wherein activation of the second activator to move the slide into the disengaged position includes resetting the trigger.
15. A coupler as claimed in either one of claims 13 or 14 wherein the second actuator is a hydraulically operated actuator.
16. A method of securing a work attachment to a work vehicle using a coupler, wherein the work attachment includes a first pin and a second pin and wherein the coupler includes: a coupler body having a first engagement portion which is configured to accept the first pin, a second engagement portion configured to accept the second pin, and a guide; a slider configured to slide along the guide, wherein a body of the slider includes a first locking portion and a second locking portion; 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 including the steps of: a) locating the first pin on the work attachment in the first engagement portion of the coupler body; b) inserting the second pin into the second engagement portion of the coupler body so that the second pin contacts and releases the trigger; c) 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.
17. A method as claimed in claim 16 including the step of: d) 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.
18. A method as claimed in claim 17 wherein the slider is moved manually.
19. A method as claimed in claim 17 wherein the slider is moved by action of a second activator.
20. A method as claimed in any one of claims 17 to 19 wherein the step of moving the slider into the disengaged position includes resetting the trigger.