A coupler includes first and second spaced-apart ribs each defining first and second bores. The first bore of the first rib is aligned with the first bore of the second rib on a first pin-on axis, and the second bore of the first rib aligned with the second bore of the second rib on a second pin-on axis. A first hook assembly includes a first hook adapted to receive a first associated attachment pin. The first hook assembly is fixed relative to the first and second ribs. A second hook assembly includes a second hook adapted to receive a second associated attachment pin. The second hook assembly is selectively pivotable relative to the first and second ribs toward and away from the first hook assembly. An actuator is operatively connected to the second hook assembly to pivot the second hook assembly selectively relative to the first and second ribs.

BACKGROUND OF THE INVENTION

The present invention relates to couplers used to secure attachments such as buckets, air-operated hammers, shears, etc. fixedly and operatively to the distal end of a arm of a tractor, backhoe, excavator or other type of arm-equipped construction/agricultural equipment. As is generally well known, couplers are used as an alternative to a pin-on connection for fixedly and operatively securing an implement to the distal end of an arm which is, in turn, secured to a boom of a construction/agricultural machine such as a backhoe or excavator.

Spread-style couplers are generally known. These couplers are connected to an arm by a pin-on connection at a first pivot point and are connected to a control link by a pin-on connection at a second pivot point. These prior couplers include front and rear hooks that open in respective opposite directions oriented outwardly away from each other. Each hook is pivotably connected to the body of the coupler, i.e., each hook pivots about a separate axis. In use, the hooks are collapsed toward each other are placed between front (first) and rear (second) pins of a bucket or other attachment and the hooks are then spread-apart from each other, using a screw jack or other means. Upon being spread sufficiently far apart, the rear hook engages the rear pin of the implement and the front hook engages the front pin of the implement which results in the implement being operatively connected to the arm.

Known spread-style couplers are deficient for many reasons. One notable disadvantage of known spread-style couplers is that both hooks pivot relative to the coupler body. This results in an excessive amount of pivot points and reduces the strength of the coupler. Similarly, during digging and other operations, large loads are exerted upon the rear hook (inwardly located toward the boom-equipped machine) and the pivotable nature of this hook is not a desirable trait to encounter these large loads. Another deficiency of these known couplers results from the fact that the pivot points of the hooks are not coincident with the pivot points where the coupler is pinned to the arm and control link.

In light of the foregoing, a need has been identified for a new and improved spread-style coupler that overcomes the foregoing deficiencies and others while providing better overall results.

SUMMARY OF THE INVENTION

In accordance with a first aspect of the present invention, a coupler comprises first and second spaced-apart ribs each defining first and second bores. The first bore of the first rib is aligned with the first bore of the second rib on a first pin-on axis, and the second bore of the first rib aligned with the second bore of the second rib on a second pin-on axis. A first hook assembly includes a first hook adapted to receive a first associated attachment pin. The first hook assembly is fixed relative to the first and second ribs. A second hook assembly includes a second hook adapted to receive a second associated attachment pin. The second hook assembly is selectively pivotable relative to the first and second ribs toward and away from the first hook assembly. An actuator is operatively connected to the second hook assembly to pivot the second hook assembly selectively relative to the first and second ribs.

In accordance with another aspect of the present invention, a method of operatively connecting an attachment to a coupler comprises inserting a first attachment pin into a first hook of the coupler and pivoting the coupler about the first attachment pin until a second attachment pin is aligned with a second hook of the coupler. The second hook is then pivoted away from the first hook about a pivot axis until said first and second attachment pins are fully seated in the first and second hooks, respectively. The pivot axis is coincident with a pin-on axis about which the coupler pivots relative to a control link to which the coupler is connected.

In accordance with another aspect of the present invention, a coupler comprises an upper portion defining a first pin-on axis and a second pin-on axis. The coupler further comprises a first hook assembly including a first hook adapted to receive a first associated attachment pin. The coupler further comprises a second hook assembly including a second hook adapted to receive a second associated attachment pin. The second hook assembly is pivotably connected to the upper portion and selectively pivotable about the first or second pin-on axis toward and away from the first hook assembly. An actuator is operatively connected to the second hook assembly to pivot the second hook assembly.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring initially toFIGS. 1-3, a coupler C formed in accordance with the present invention comprises two main sections: (i) an upper section U configured or adapted for pivotable pin-on connection to an arm and control link of an associated excavator, wheel-loader backhoe or any other associated machine having an arm and control link to which the coupler C is operatively connected; and, (ii) a lower section L configured or adapted for releasable operative connection to first and second spaced-apart, parallel pins (see pins P1,P2inFIGS. 12A-12C) that are connected to an associated bucket, shear, grapple, blade or any other associated attachment. The term “parallel” as used herein is intended to mean exactly parallel and slight variations therefrom as caused by tolerances, minor deformation during welding or use, etc.

The upper section U comprises first and second parallel spaced-apart ribs R1,R2that define an open channel UC therebetween. The first rib R1comprises first and second spaced-apart bosses S1a,S1bthat define respective first and second bores B1a,B1b. Likewise, the second rib R2comprises first and second spaced-apart bosses S2a,S2bthat define respective first and second bores B2a,B2b. The bores B1a,B2aand bores B1b,B2bare aligned with each other and preferably cylindrically defined about respective parallel axes L1,L2. The aligned bores B1a,B2aare dimensioned for close, sliding receipt of a first associated pin-on pin PO1. The aligned bores B2a,B2bare dimensioned for close, sliding receipt of a second associated pin-on pin P02. In the illustrated embodiment, the first associated pin-on pin PO1is used to effect a pivotable pin-on connection between the coupler C and an arm of the associated excavator, backhoe or other machine, while the second associated pin-on pin PO2is used to effect a pivotable pin-on connection between the coupler C and the control link of the associated excavator, backhoe or other machine. The upper section U, including the ribs R1,R2and bosses S1a,S1b,S2a,S2b(and pins PO1,PO2), is defined from any suitable material(s) known in the art such as various metals and alloys thereof such as steel alloys or the like. The spacing between the ribs R1,R2and position and size of the bosses S1a,S1b,S2a,S2bcan vary as required to allow for suitable pin-on connections with the associated machine.

The lower section L of the coupler C comprises first and second hook assemblies H1,H2that are connected to the upper section U and project outwardly therefrom. Unless otherwise noted, the lower section L and the subassemblies thereof are defined from any suitable material(s) known in the art such as various metals and alloys thereof such as steel alloys or the like. The first hook assembly H1comprises a first cross-plate XP1to which first and second rear hook plates K1a,K1bare connected in parallel spaced-apart relation. The first and second rear hook plates K1a,K1bdefine respective recesses RC1a,RC1bthat cooperate to define a first hook FH. A first fill plate FP1extends between and interconnects the hook plates K1a,K1b. The fill plate is conformed and dimensioned to cooperate with the recesses RC1a,RC1bto define the first hook FH.

Thus, the first and second rear hook plates K1a,K1band the first fill plate FP1together define the first hook FH. The first hook FH, as described in further detail below, is conformed and dimensioned to receive a first associated pin P1(FIGS. 12A-12C) of an associated attachment such as a bucket or blade. The first cross-plate XP1is preferably fixedly and immovably secured to the ribs R1,R2and laterally spans the channel UC.

The second hook assembly H2comprises a second cross-plate XP2to which first and second front hook plates K2a,K2bare connected in parallel spaced-apart relation. The first and second front hook plates K2a,K2bdefine respective recesses RC2a,RC2bthat cooperate to define a second hook SH. A second fill plate FP2extends between and interconnects the first and second front hook plates K2a,K2b, and the second fill plate FP2is conformed and dimensioned to cooperate with the recesses RC2a,RC2bin the definition of the second hook SH, i.e., the recesses RC2a,RC2band the second fill plate FP2together cooperate to define the second hook SH.

The second hook assembly H2further comprises first and second ears E1,E2and the second cross-plate XP2extends between and is connected at its opposite ends to the respective ears E1,E2. The ear E1is pivotably connected to the rib R1and the ear E2is pivotably connected to the rib R2. More particularly, the ears define apertures EA1,EA2that closely rotatably receive the bosses S1b,S2b, respectively. In some cases it may be desirable to utilize a brass or other bushing located between the ear apertures EA1,EA2and respective bosses S1b,S2bto minimize wear and to provide a replaceable wear element. Also, in another alternative embodiment, the bosses S1b,S2bcan, themselves, be provided as or defined by removable and replaceable bushings made of brass or the like (e.g., flanged bushings having enlarged flanges abutted with the ribs R1,R2and cylindrical bodies extending through the ribs R1,R2and ears E1,E2, respectively).

Thus, the first and second front hook plates K2a,K2band the second fill plate FP2cooperate to define the second hook SH. The second hook SH, as described further below, is conformed and dimensioned to receive a second associated pin P2of a bucket, blade or other associated attachment (see FIGS.12A-12C).

The first hook FH and the second hook SH open outwardly away from each other in generally opposite directions. Because the ears E1,E2of the second hook assembly SH are pivotably connected to the ribs R1,R2, the second hook assembly H2, including the second hook SH, is movable toward and away from the first hook FH as shown by the arrows A1inFIGS. 12A-12Cand as described further detail below.

The coupler C further comprises mechanical, hydraulic, electro-mechanical and/or other type actuator or means for selective moving the second hook assembly H2relative to the first hook assembly H1and for selectively fixedly securing the second hook assembly H2in a desired select operative position relative to the first hook assembly H1. In the illustrated embodiment, the coupler C comprises a manually driven (or optionally an electro-mechanically or hydraulically driven) screw jack assembly J connected between the second hook assembly H2and the first hook assembly H1(or some other fixed part of the coupler C) so that the screw jack assembly J controls the movement and position of the second hook assembly H2and the second hook SH relative to the first hook assembly H1and first hook FH. In another embodiment, the screw jack assembly J is replaced by a conventional hydraulic cylinder that extends and retracts axially in response to hydraulic pressure applied in first and second orientations, respectively.

With reference now toFIGS. 10A-10C, the screw jack assembly J comprises a screw member J10and first and second housing assemblies J12,J14. The first housing assembly J12is secured to the first hook assembly H1and the second housing assembly J14is secured to the second hook assembly H2. The screw member J10is threaded along at least a portion of its length and extends along a longitudinal axis L3. It is to be noted that inFIGS. 10A,10B,12A-12C and13, certain internal and/or hidden components are illustrated in solid lines rather than broken lines to facilitate understanding of the invention.

The first housing assembly J12includes an internally threaded nut member or like structure J30that is threadably engaged with the first end J10aof the screw member J10. Thus, the screw member J10is advanced and retracted relative to the first housing assembly J12upon rotation of the screw member J10in first and second directions about the axis L3, respectively. The first housing J12comprises an enclosed hollow tail or extension J16that receives and accommodates the portion of the screw member J10that protrudes through the nut J30when the screw member is threadably advanced through the nut structure J30. The hollow extension J16helps to prevent contamination of and damage to the portion of the screw member J10received therein.

The second end J10bof the screw member J10is connected to the second housing assembly J14in a manner that allows rotational movement of the screw member J10about the axis L3without any threaded engagement between the screw member J10and the second housing assembly J14. As such, rotation of the screw member J10does not result in threaded advancement or retraction of the second housing assembly J14relative to the screw member J20. More particularly, the second housing assembly J14includes or defines a recess J15that receives a portion of the second end J10bof the screw member J10, and a shank J11of the screw member projects through an aperture J19defined in the second housing assembly J14. A removable C-collar J18or the like is used to secure the screw member J10to the second housing assembly J14to prevent axial separation between these two members J10,J14while allowing the screw member J10to rotate about its longitudinal axis L3. The C-collar J18(see alsoFIG. 8) is positioned axially between the second housing assembly J14and a shoulder J11cof shank J11and secured to the second housing assembly using a screw or other fastener J18F. The C-collar J18captures the second housing assembly J14between itself (the C-collar J18) and an enlarged radial flange J10dof the screw member J10so that the screw member J10cannot be separated axially from the second housing member J14(limited axial movement or “play” of the screw member J10relative to the second housing assembly J14is allowed and desirable for reasons noted below).

As noted, the first and second housing assemblies J12,J14are secured respectively to the first and second hook assemblies H1,H2in the illustrated embodiment. During use of the screw jack assembly to pivot the second hook assembly H2relative to the first hook assembly H1, limited angular movement between the screw member J10and the hook assemblies H1,H2must be accommodated. In the illustrated embodiment, the first housing assembly J12is pivotably connected to the first hook assembly H1and the second housing assembly J14is pivotably connected to the second hook assembly H2.

More particularly, as illustrated herein, the first housing assembly J12comprises first and second cylindrical hubs J32a,J32bprojecting outwardly from opposite lateral sides thereof. These hubs J32a,J32bare pivotably or rotatably engaged with respective cylindrical hub-receiving portions J33a,J33bof the first hook assembly H1as shown in FIG.7. Likewise, the second housing assembly J14comprises first and second cylindrical hubs J34a,J34bprojecting outwardly from opposite lateral sides thereof. These hubs J34a,J34bare pivotably or rotatably engaged with respective cylindrical hub-receiving portions J35a,J35bof the second hook assembly H2as shown in FIG.7. It is preferred that each the hub-receiving portions J33a,J33b,J35a,J35bcomprise a recess and a keeper that is selectively secured adjacent the recess by a fastener to capture the hub J32a,J32b,J34a,J34badjacent the recess.FIG. 10Dshows a suitable arrangement for the hub-receiving portions J33a,J33b,J35a,J35b(only the portion J35bis visible inFIG. 10Dbut the others J33a,J33b,J35aare identical). The hub-receiving portion J35bcomprises a first or base member36athat is connected to or an integral part of the second hook assembly H2and defines a partially-cylindrical recess36b. A keeper37adefines a partially-cylindrical recess37band is selectively and releasably connected to the first member36avia fastener37f. It can be seen that the recesses36b,37bof the base36aand keeper37acooperate to define a cylindrical hub-receiving space for the cylindrical hubs J32a,J32bJ34aJ34b.

The shank J11of the screw member J10comprises a head portion J30defined as a polygon or other suitable shape for being drivingly engaged by an associated tool (see also FIG.8). Thus, the screw member J10is rotatable clockwise and counter-clockwise about its longitudinal axis L3via torque applied to the head J30from an associated tool. It is preferred that the screw jack assembly J be configured as shown herein, with the driving head J30located near the second hook assembly H2rather than the first hook assembly H1, in that the driving head J30is easily visible during coupling and decoupling of attachments, although it is not intended that the invention be limited only to the illustrated arrangement.

As noted, a wrench or other took is used on the head portion J30to rotate the screw member J10as desired to control the position of the front or second hook assembly H2on the arc A1(FIGS. 12A-12C) which, in turn, controls the distance between the first hook FH and second hook SH. With reference toFIGS. 12A-12C, the coupler C is used to operatively couple with a bucket or other associated attachment by positioning the first and second hooks FH,SH between first and second pins P1,P2of the associated attachment, with the first pin P1fully or partially received in the first recess FH as shown in FIG.12A. Thereafter, the screw J10is rotated by a tool acting on the head portion J30to pivot the second hook assembly H2on the arc A1away from the first hook portion H1so that the second pin P2of the bucket or other associated attachment moves partially (FIG. 12B) and then fully (FIG. 12C) into the second hook SH. The screw member J10is rotated still further until both the first pin P1and second pin P2are fully and firmly seated in the respective recesses FH,SH so that the associated bucket or other attachment is operatively secured to the coupler C.

The threads J32on the screw member J10are designed to inhibit rotation of the screw member J10under axial loading thereof. For example, in one preferred embodiment, it is preferred that ACME threads be used to achieve this result. Thus, when the coupler C is in use and loads are exerted on the second hook assembly H2in a direction toward the first hook assembly H2, the screw member J10will resist rotation owing to the ACME threads. In one example the screw member J10is a 1.25 inch diameter screw with ACME threads that are configured as five threads/inch single lead or as otherwise deemed appropriate for the size and rating of the coupler C.

As noted above, limited axial movement or “play” is present between the second housing assembly J14and the screw member J10. This is desirable for operation of a disc lock mechanism J50that forms a part of the present coupler C. With reference toFIGS. 10A,10B and11, the second housing assembly J14defines an internal bearing wall J52(see enlargedFIG. 11) that partially defines the recess J15. As noted above, the screw member J10includes an enlarged radial flange J10dlocated adjacent the bearing wall J52. A Belleville spring/washer or disc spring member J54is arranged coaxial with the screw member J10axially between the flange J10dand the bearing wall J52, preferably with the concave portion thereof oriented toward the bearing wall J52. The disc spring J54preferably requires a high force of about 700-800 pounds to be completely compressed or flattened.

In use, rotation of the screw member J10results in spreading of the second hook assembly H2away from the first hook assembly H1as described above, and the disc lock mechanism has no material effect on this initial operation. However, as the first and second hooks FH,SH engage their respective attachment pins P1,P2and resist further spreading relative to each other, the flange J10dand bearing wall J52are urged forcibly toward each other against the biasing force of the disc spring J54. Upon sufficient rotation of the screw member J10, the disc spring will become partially and, ultimately, fully compressed when the first and second attachment pins P1,P2are fully and operatively seated in the respective hooks FH,SH. When compressed or partially compressed, the disc spring J54exerts constant axial forces on the flange J10dand bearing wall J52in opposite axial directions, i.e., the disc spring J54attempts to urge the flange J10dand bearing wall J54axially away from each other. This axial loading results in high friction at the interface of the flange J10dwith the disc J54and also results in high friction at the interface of the disc J54with the bearing wall J52. These high friction conditions prevent or severely inhibit unintended or free rotation of the screw member J10during use and, thus, “lock” the screw member J10in position when the first and second pins P1,P2are fully and operatively seated in the first and second hooks FH,SH. Those of ordinary skill in the art will recognize that the disc lock mechanism J50is “touch sensitive” in that it has no meaningful effect on rotation of the screw member J10until both the first and second hooks FH,SH are at least partially engaged with the respective pins P1,P2. Furthermore, the use of a Belleville spring J54as described herein is preferred because the spring J54requires only a very small axial compression or displacement to be fully compressed.

The screw jack assembly J preferably comprises a bellows J60, made from rubber, plastic or the like (see e.g.,FIGS. 1-7and10C). The bellows J60is secured at its opposite ends adjacent the first and second housing assemblies J12,J14, respectively, by clamps J62a,J62bor the like. The bellows J60encases the screw member J10between the first and second housing assemblies J12,J14and lengthens and shortens as required to accommodate different spacing between the housings J12,J14. The bellows J60prevents or at least inhibits flow of dirt and water to the screw member J10and the housings J12,J14.

The first hook FH is conformed or defined so that its open mouth J90(seeFIG. 4) is fanned or widely diverging moving outwardly away from an innermost end J94. This shape facilitates insertion of the first attachment pin P1into the first hook FH. The mouth J90of the first hook FH is defined between first and second terminal ends J90a,J90bof the first hook FH, and these first and second terminal ends J90a,J90bare spaced at least approximately the same distance from the innermost end J94of the first hook FH. The second hook SH comprises a mouth J92defined between first and second terminal ends J92a,J92bof the second hook SH. The second terminal end J92bis spaced farther from the innermost end J96of the second hook SH as compared to the first terminal end J92a. Preferably the second terminal end J92bis spaced from the innermost surface J96at least 1.5-2.0 times the distance between the first terminal end J92aand the innermost surface J96. The second hook SH thus comprises a smooth guide ramp J98located opposite the first terminal end J92aand that extends outwardly away from the innermost surface J96toward and into the second terminal end J92b. In use during coupling operations, a first attachment pin P1is received in the first hook FH and the coupler C is then pivoted about the first attachment pin P1so that the second attachment pin P2abuts the ramp J98of the second hook SH. The second hook SH is then pivoted away from the first hook FH as described above so that the second attachment pin P2slides on the ramp J98toward the innermost surface J96and until the second pin P2is fully received in the second hook SH.

As illustrated, it is preferred that both the first and second hooks FH,SH be defined by multiple arcuate or circular surfaces defined along respective multiple radii. This allows multiple pin diameters for the pins P1,P2to be accommodated in each hook FH,SH and also increases the contact surface area between each pin P1,P2and the surfaces defining the hooks FH,SH. As shown, e.g., inFIGS. 1-3and5, the first hook FH includes a first surface S1defined by a first radius centered at a first point, second surfaces S2a,S2beach defined by a second radius centered at a second point and third surfaces S3a,S3beach defined by a third radius centered at a third point. In one example, the first radius equals 1.50 inches, the second radius equals 1.75 inches and the third radius equals 2.16 inches. Similarly, the second hook SH includes a first surface T1defined by a first radius centered at a first point, second surfaces T2a,T2bdefined by a second radius centered at a second point and third surfaces T3a,T3bdefined by a third radius centered at a third point. In one example, the radius defining the first surface T1is equal to 1.5 inches, the radius defining the second surfaces T2a,T2bis equal to 1.75 inches and the radius defining the third surfaces T3a,T3bis equal to 2.0 inches.

FIG. 13illustrates an alternative coupler C′ formed in accordance with the present invention. Except as shown and/or described, the coupler C′ is identical to the coupler C andFIG. 13uses reference characters that are identical to those used inFIGS. 1-12Cto indicate like parts relative to the coupler C. Unlike the coupler C, however, the coupler C′ includes at least one lift eye LE that projects outwardly from the second hook assembly H2.

FIG. 13also illustrates a preferred construction of the coupler C,C′ wherein the surfaces S1; S2a,S2b; S3a,S3bare defined by radii centered respectively at O1;O2;O3and the surfaces T1; T2a,T2b; T3a,T3bare defined by radii centered respectively at O4;O5;O6. A line interconnecting the origins O1-O3is parallel or nearly parallel (within 5 degrees of parallel) to a plane PL1including the axes L1,L2. On the other hand, when the second hook SH is fully pivoted away from the first hook FH as shown inFIG. 13, a line interconnecting the origins O4-O6is inclined relative to the plane PL1so that it intersects the plane PL1moving away from the first hook FH at an angle of 10 to 20 degrees, preferably about 15 degrees. This arrangement ensures that a second attachment pin P2will be effectively captured in the second hook SH for all operative positions of the second hook SH, i.e., the line interconnecting the origins O4-O6will always lie between a position parallel to the plane PL1and the position shown inFIG. 13when the first and second attachment pins P1,P2are fully and operatively seated in the hooks FH,SH for all spacings between the first and second attachment pins P1,P2. This ensures that the second attachment pin P2will always be effectively captured in the second hook SH even when the second attachment pin P2is located relatively close to the first attachment pin P1.

It is preferred that the coupler C,C′ be constructed so that, whenever possible, a connection of two plates or other components is carried out by insertion of one or more tabs projecting from the first component into corresponding mating slot(s) defined in the second component and then welding the first and second components together. As shown inFIG. 6, for example, the plates K1a,K1b,K2a,K2binclude tabs K3that are received in slots K4defined in the cross-plates XP1,XP2. Also, although they are not all visible, the cross-plates XP1,XP2include tabs XP3that are received in slots XP4defined by the ribs R1,R1(see, e.g., FIG.2). This construction technique facilitates construction without a “jig” and also can be used to ensure that parts are not improperly positioned.

The coupler C,C′ can include an optional screw jack assembly J′ that is identical to the screw jack assembly J, except as otherwise shown and/or described here. Accordingly, like components of the screw jack assembly J′ relative to the screw jack assembly J are identified with like reference characters that include a primed (′) suffix. New components are identified with new reference characters.

The screw jack assembly J′ comprises a screw member J10′ and first and second housing assemblies J12′,J14′. The first housing assembly J12′ is secured to the first hook assembly H1and the second housing assembly J14′ is secured to the second hook assembly H2. The screw member J10′ is threaded along at least a portion of its length and extends along a longitudinal axis L3′.

The first housing assembly J12′ comprises a first tube member TU1and the second housing member comprises a second tube member TU2. The first tube member TU1is telescopically received inside the second tube member TU2so that the first and second tube members TU1,TU2cooperate to enclose at least a portion of the screw member J10′ that extends between the housing assemblies J12′,J14′. A seal JS is connected to the second tube member TU2and sealingly engages the first and second tube members TU1,TU2to inhibit entry of water, dirt and other contaminants between these members into the space enclosing at least a portion of the screw J10′.

An internally threaded nut member or like structure J30′ is connected to the first tube member TU1or other portion of the first housing assembly J12′ and is threadably engaged with the screw member J10′. Thus, upon rotation of the screw member J10′ about the axis L3′ the nut member J30′ and the first housing assembly J12′ are advanced or retracted on the screw member J10′ relative to the second housing assembly J14′ depending upon the direction in which the screw member J10′ is rotated. The tube members TU1,TU2slidably extend and retract relative to each other but always cooperate to enclose and protect the portion of the screw member J10′ extending between the first and second housing assemblies J12′,J14′. Advancement of the nut member J30′ on the screw member J10′ is limited by a first flange stop member ST1in a first direction and is limited by a second flange stop member ST2(or by abutment of the tube members TU1,TU2) is a second direction.

The second end J10b′ of the screw member J10is connected to the second housing assembly J14′ in a manner that allows rotational movement of the screw member J10′ about the axis L3′ without any threaded engagement between the screw member J10′ and the second housing assembly J14′. The second housing assembly J14′ includes or defines a recess J15′ that receives a portion of the second end J10b′ of the screw member J10′, and a shank J11′ of the screw member J10′ projects through an aperture J19′ defined in the second housing assembly J14′. A clamp J18′ or the like is engaged with a circumferential groove of the shank J11′ to secure the screw member J10′ to the second housing assembly J14′ to prevent axial separation between these two members J10′,J14′ while allowing the screw member J10′ to rotate about its longitudinal axis L3′.

The first housing assembly J12′ comprises first and second cylindrical hubs J32a′,J32b′ projecting outwardly from opposite lateral sides thereof (FIG.14A). The second housing assembly J14′ comprises first and second cylindrical hubs J34a′,J34b′ projecting outwardly from opposite lateral sides thereof (FIG.14A). The first and second housing assemblies J12′,J14′ are secured to the first and second hook assemblies H1,H2in the same manner as described above.

The shank J11′ of the screw member J10′ comprises a head portion J30′ that is drivingly engaged by a output shaft102of an associated rotary hydraulic motor100. Thus, the screw member J10′ is rotatable clockwise and counter-clockwise about its longitudinal axis L3′ via torque applied to the head J30′ by the output shaft102of the motor100. The motor100is bolted or otherwise secured to the second housing assembly J14′. In the preferred embodiment, when the motor100is bolted to the second housing assembly J14′, the motor100abuts and holds the clamp J18′ in its operative position where the clamp J18′ axially secures the screw member J10′.

During use of the coupler C,C′ including the screw jack assembly J′, the motor100is used to selectively rotate the screw member J10′ as desired to pivot the second hook assembly H2relative to the first hook assembly H1. The motor100is also used to prevent undesired rotation of the screw member J10′ under axial loading of the screw member J10′ during use of the coupler. The screw member J10′ also preferably utilizes ACME threads as described above for threadably connecting to the nut member J30′. In one example, the screw member J10′ is a three inch diameter screw member having single lead ACME threads arranged at four threads/inch.

The screw jack assembly J′ also preferably includes a disc lock mechanism J50′ that operates in a corresponding manner as described above in relation to the disc lock J50.

The motor100is preferably a hydraulic motor operating at about 1250 psi. The motor100is pressurized in a first orientation to rotate the output shaft102(and screw member J10′) in a first direction to spread the second housing assemblies J14′ away from the first housing assembly J12′. The motor100is pressurized in a second orientation to rotate the output shaft102(and screw member J10′) in a second direction to draw the second housing assembly J14′ toward the first housing assembly J12′. During use of the coupler C,C′ with an attachment operatively connected thereto via first and second attachment pins P1,P2seated in the respective hooks FH,SH, it is preferred that the motor100be continuously pressurized in the first orientation to bias or urge the output shaft102in the first direction (even though further rotation in the first direction is not possible when the pins P1,P2are fully seated in the hooks FH,SH) to prevent unintended rotation of the output shaft102in the opposite second direction as could lead to decoupling of the attachment from the coupler C,C′. Furthermore, it is preferred that a pilot check valve be used to ensure that the output shaft102is rotatable in the second direction only upon the hydraulic motor100being actively pressurized in the second orientation with pressure above a select threshold. The use of a pilot check valve in this manner prevents rotation of the output shaft102in the second direction upon mere loss of hydraulic pressure in the first orientation due to a cut hose or the like.

The hydraulic fluid used to drive the motor100can also serve as a lubricant for the screw member J10′. In this arrangement, hydraulic fluid expelled by the motor100or otherwise available to drive the motor is communicated into the space enclosed by the telescoped members TU1,TU2to lubricate the screw member J10′.

The coupler C,C′ including the hydraulic motor100is also manually operable in the same manner as the screw jack assembly J simply by removal of the hydraulic motor100to allow the screw member J10′ to be drivingly engaged, either directly by a mating tool or indirectly through a shaft or adapter. In the latter case, the motor100is replaced by a shaft having a first end that drivingly mates with the screw member J10′ and a second end that includes or defines a driving head adapted for driving engagement by an associated tool.

It is most preferred that the first hook assembly H1be fixed relative to the ribs R1,R2and that the second hook assembly H2be movable relative to the ribs R1,R2because the first hook assembly H1, which connects to a first or inner attachment pin P1, will typically encounter higher loads during digging and other operations as compared to the second hook assembly H2. Furthermore, as disclosed herein, it is preferred that the ears E1,E2of the second hook assembly H2pivot about the bosses S1b,S2bthrough which a pin-on pin PO2passes so that the second hook assembly H2pivots about the pin-on axis L2(or stated another way, the hook assembly H2pivots about an axis coincident with the pin-on axis L2). This arrangement provides added strength relative to prior designs and minimizes pivot points. The fact that the ears E1,E2of the second hook assembly H2pivot about the pin-on axis L2is also thought to be desirable to save space and provide a preferred geometry relative to prior spread-style couplers.

It is preferred that the first hook assembly H1be permanently fixed in position relative to the ribs R1,R2as by welding or the like as disclosed above. However, as used herein, the term “fixed” and other equivalent terms are intended to encompass any other arrangement where the first hook assembly H1is made immovable relative to the first and second ribs R1,R2during use of the coupler C,C′. Thus, for example, the term “fixed” as used herein is intended to encompass an arrangement wherein bolts or other fasteners or other means are used to secure the first hook assembly H1immovably relative to the ribs R1,R2, even if the position of the first hook assembly H1relative to the ribs R1,R2is selectively adjustable when the coupler is not in use.

The size of the coupler C,C′ will vary depending upon the machine to which it is to be connected and the size of the associated attachments to be operatively engaged by the coupler. For example, the width of the first hook FH and second hook SH can be set to a minimum width for a group or class of attachments. Thus, the coupler C,C′ can be operatively coupled to all attachments in the class (spacers can be used between the opposite lateral sides of the hooks FH,SH and the attachment if needed).

Those of ordinary skill in the art will recognize that the second hook assembly H2can alternatively be pivotable about the first pin-on axis L1without departing from the overall scope and intent of the present invention. Also, the second hook assembly H2can be fixed and the first hook assembly H1pivotable about either the first pin-on axis L1or second pin-on axis L2.

Modifications and alterations will occur to those of ordinary skill in the art to which the invention pertains upon reading and understanding this specification. It is intended that the invention be construed as including all such modifications and alterations as encompassed by the claims.