GB2238035A

GB2238035A - Coupling

Info

Publication number: GB2238035A
Application number: GB8925537A
Authority: GB
Inventors: John Donachie
Original assignee: Christopher John Littler
Current assignee: Christopher John Littler
Priority date: 1989-11-11
Filing date: 1989-11-11
Publication date: 1991-05-22
Anticipated expiration: 2009-11-11
Also published as: GB8925537D0; GB2238035B

Abstract

An excavator accessory coupling is in the form of a coupling body (10) which in use is secured to a dipper arm and ram arm of an excavator by means of apertures (14). The front surface of the coupling body is provided with a channel-section member (16), which in use is manoeuvred such that it receives an elongate bar (28) secured to an accessory such as a tool. An additional attachment member (18) having an elongate aperture (22) is movable and is securable in position by means of three bolts (26) passing through elongate apertures (24) in the coupling body. A retaining pin can be inserted through apertures in lugs on the accessory to be secured, and by suitable adjustment of the position of the lower member (18), the accessory can be secured to the arm. The adjustability of the lower member (18) permits the rapid securing of accessories of different manufacture. Further couplings in the form of open ended hooks adjustable in position by a screwed member (Fig 3) and a two part locking coupling (Fig 2) are also disclosed. <IMAGE>

Description

DESCRIPTION COUPLING The present invention relates to couplings, and in particular, but not exclusively, to couplings for use with excavators.

Excavators are often provided with accessories, such as a bucket, attached to an arm which is pivotally connected to the excavator and which is movable by means of application of hydraulic pressure to suitably-located hydraulic rams. Normally, the accessory is pivotally attached to a first, "dipper arm", and the bucket may be pivotally attached about the pivot point by means of a "ram arm", which is extensible by means of application of hydraulic pressure to a fluid ram, and which is pivotally attached at one end to further lugs on the accessory. By appropriate manipulation of the hydraulic rams, the digging mechanism can, for example, effect a digging motion.

The accessories are attached by means of aligning apertures in the dipper arm and ram arm with corresponding apertures in lugs located on the upper and lower portions respectively of the accessory, and the accessory is then secured to the arm by passing stainless steel pins through the aligned apertures and then securing the pins in position. Such a securing arrangement allows the accessory to be detached from the excavator if it is desired to remove it, e.g. in order to replace it with a different accessory, or for the purposes of repair.

One problem with the known coupling arrangement is that each excavator manufacturer normally manufactures accessories which are designed for use specifically with its own equipment. For example, two excavators of different manufacture will not be able to use each other's buckets since the different types of buckets from the two manufacturers are not compatible or interchangeable.

It is thus an object of the present invention to provide a excavator coupling which overcomes the aforementioned disadvantage.

In accordance with a first aspect of the present invention, an excavator accessory coupling comprises a coupling body having attachment means for connection to a dipper arm and ram arm of an excavator, a channelsection member, located on one of the coupling body and an excavator accessory, adapted to receive a member secured to the other of the coupling body and the excavating accessory, and a further accessory attachment means, movable to vary its separation from the channelsection member.

In this way, in order to pick up an excavator accessory, it is necessary merely to engage the elongate bar in the channel-section member whereupon lifting of the accessory will permit the further attachment means to be secured.

In one embodiment, the position of the further attachment means is adjusted before the accessory is lifted, thus allowing a securing member to be connected once the accessory is lifted. In another embodiment, the further attachment means is adjusted when the accessory is lifted, and engagement of the further attachment means with a portion of the accessory secures the accessory to the coupling. The adjustment may be effected by means of a screw-threaded connection, and in one embodiment comprises a channel-section member on one of the coupling and the accessory movable relative to, and into engagement with, an elongate member on the other of the coupling and the accessory.

The coupling body is preferably designed to be connected permanently to an excavator, and in view of the adjustability of the further attachment means of the coupling, it is possible to use it with accessories manufactured by different manufacturers.

A further problem encountered with known devices is that it takes a considerable length of time to couple an accessory to the excavator, since it is firstly necessary to align the apertures in the arms with corresponding apertures in the accessory, and then to insert the necessary securing pins manually. This can take a considerable length of time, especially since it is necessary to align the apertures accurately before the securing pins can be inserted.

It is thus a further object of the present invention to provide a coupling which overcomes this disadvantage.

In accordance with a second aspect of the present invention, an excavator coupling comprises a first portion adapted to be connected to the dipper arm and ram arm of an excavator and a second portion adapted to be secured to an excavator accessory, one of the first and second portions being provided with a channelsection member adapted to receive a portion of the other of the first and second portions, the coupling further comprising a first power-operated securing member located on the first portion adapted to be releasably engageable with a second securing member of the second portion.

In this way, it is merely necessary to engage the elongate portion with the channel-section member, whereupon lifting of the dipper arm causes the second portion and the accessory attached to it to move into the required position by pivoting about the channel section member/elongate portion to permit engagement of the power-operated securing member with the securing member on the second coupling portion. This enables an operator to engage and disengage an excavator accessory without leaving the cab of the excavator.

In one embodiment, the first securing member on the first portion comprises a latch, which is preferably engageable with a lug on the second protion which, in use, may project through an aperture in the first portion.

In another embodiment, one securing member comprises a member which in one orientation may pass through an aperture in the other securing member and which are relatively rotatable to prevent disengagement of the first and second members from the aperture.

Preferably, the coupling comprises a fluidactivated, e.g. hydraulic ram.

By way of example only, specific embodiments of the present invention will now be described, with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a first embodiment of excavator coupling in accordance with the present invention; Fig. 2 is a perspective view of a second embodiment of excavator coupling in accordance with the present invention; and Fig. 3 is a perspective view of a third embodiment of excavator coupling in accordance with the present invention.

Referring firstly to Fig. 1, the coupling device comprises a generally flat plate 10, from whose rear surface two parallel flanges 12 extend perpendicularly.

Each flange 12 is provided with two apertures 14, one located adjacent each end of the flange. In use, the upper apertures (as seen in Fig. 1) are aligned with complementarily-positioned and shaped apertures on the end of an excavator dipper arm, and the lower two apertures are aligned with corresponding apertures in the excavator ram arm, securing pins being pushed through and secured in each set of aligned apertures, thereby securely connecting the coupling to the excavator arm or arms.

The front surface of the plate 10 is provided with a upper channel-section member 16 and a lower, adjustable securing member 18. The channel-section member 16 is generally U-shaped in cross-section, and is provided with an outwardly-flaring front lip 20 to aid in the coupling operation, as will be described later.

The lower coupling member 18 is in the form of an elongate bar which is provided with a cylindrical bore 22 therethrough, extending parallel to the plane of the plate 10 and perpendicularly to the longitudinal direction of the flanges 12. The elongate aperture 22 in the adjustable attachment means 18 is adapted to be alignable with the apertures in each of the two lugs (not illustrated) on a conventional accessory, e.g. a bucket, whereupon a stainless steel retaining pin can be inserted through the apertures in the bucket lugs and through the bore 22 and secured in position.

It will also be noted from Fig. 1 that the additional attachment means 18 is movable in a direction parallel to the longitudinal direction of the flanges 12. This is achieved by providing three parallel apertures 24 in the plate 10, each of which is adapted to receive the shank of a bolt 26, each of which is screw-threadedly received in a correspondingly-tapped bore in the adjustable attachment member 18. The head of each of the bolts 26 is too large to pass through the aperture 24, and thus the undersurface of each bolt bears upon the rear surface of the plate 10. By partially unscrewing the bolts 26, it is thus possible to adjust the location of the attachment means 18, but the engagement of the shanks of the bolts 26 with the corresponding slots 24 permits adjustment of the position of the attachment means 18 only in a direction parallel to the two flanges 12.When the desired position of the attachment means 18 is obtained, the three bolts 26 are tightened to secure the attachment member 18 in that position.

In use, a cylindrical metal rod 28 (illustrated schematically in Fig. 1) is passed through two aligned apertures in lugs positioned towards the top of a bucket to be attached. The separation between the upper lugs and lower lugs located on the bucket is then measured, and the position of the attachment member 18 is adjusted accordingly as previously described. The dipper arm and the ram arm are then manipulated to locate the rod 28 within the channel-section member 16, and this is aided by the outwardly-tapering lip 20. When the bar 28 is received within the channel-section member 16, the dipper arm and ram arm are then manipulated to move the bucket upwardly, which causes the bucket to pivot about the bar 28, thus bringing the bore 22 in the attachment member 18 into aligned with the apertures in the lower lugs of the bucket.The bucket is then finally secured to the coupling by passing a stainless steel pin through the aligned lug apertures and the bore 22, thus releasably securing the bucket to the excavator.

Use of this coupling enables an excavator to use accessories having different lug spacings, and thus enables an excavator of one particular manufacturer to use accessories provided by another manufacturer.

A second embodiment of the present invention is illustrated in Fig. 2, and comprises an excavator portion 30 and a bucket portion 32. The excavator portion 30 comprises a flat planar plate 34 having two upstanding parallel flanges 36 extending perpendicularly to its plane. As in the first embodiment, each flange is provided with two apertures 38 by means of which the excavator portion is attached to the dipper arm and ram arm of an excavator.

The excavator portion is also provided with a latch 40 which is displaceable along the rear surface of the plate 34 by means of an hydraulically-actuated ram 42, which is connected to a metal abutment member 44 secured between the two flanges 36. The latch 40 is constrained to move in a plane parallel to that of the plate 34 by means of two guide brackets 46 which are secured to the rear surface of the plate 34. A lug-receiving aperture 48 is provided in the planar plate 34.

The bucket coupling member 32 comprises a flat rectangular plate 50 having two elongate, parallel flanges 52 extending perpendicularly thereto. An aperture 54 is provided adjacent each end of each of the flanges 52, so that the bucket attachment member 32 may be securely connected to a bucket by aligning the apertures 54 with corresponding apertures in lugs on the bucket. The upper edge of the bucket attachment member is also provided with a downwardly-facing channelsection member 56, which is adapted to receive the upper edge 58 of the excavator attachment member.

A lug 60 is provided towards the base of the plate 50, and is adapted to extend through the aperture 48 when the upper edge 58 of the excavator attachment portion is located in the channel-section member 56 of the bucket attachment member. As can be seen from Fig.

2, the lug 60 is provided with an overhang 62, and in this way the hydraulic cylinder 42 is able to displace the latch 42 beneath the overhang 62 when the lug 60 is in the aperture 48, thereby securing the two coupling portions together.

In use, the dipper arm and ram arm of the excavator are manipulated to engage the upper edge 58 of the excavator attachment portion in the channel-section member 56 of the bucket attachment portion. If the excavator attachment portion is then pivoted and moved upwardly, the bucket attachment portion pivots about the upper edge 58 of the excavator attachment portion, and causes the lug 60 to engage with an pass through the aperture 48, whereupon the hydraulic ram 42 may be actuated to engage the latch 40 underneath the overhang of the lug 60, thereby securing the excavator arm to the bucket.

It will be noted that, since the hydraulic ram 42 may be controlled from the excavator cab, engagement and disengagement of an excavator accessory may be effected without the need for an operator to leave the cab.

A third embodiment of the present invention is illustrated in Fig. 3, and comprises a flat plate 66, from whose rear surface two parallel flanges 68 extend perpendicularly. As in the previous embodiments, each flange is provided with two apertures 70, one located adjacent each end of the flange. In use, the upper apertures are aligned with complementarily-positioned and shaped apertures on the end of an excavator dipper arm, and the lower two apertures are aligned with corresponding apertures in the excavator ram arm, securing pins being pushed through and secured in each set of aligned apertures, thereby securely connecting the coupling to the excavator arm or arms.

The front surface of the plate 68 is provided with an upper, upwardly open, channel-section member 72 and two parallel lower, downwardly open channel-section members 74. Each channel-section member is generally Ushaped in cross-section, and is provided with an outwardly flaring lip 76, 78. The upper channel-section member 72 is fixedly attached to the front surface of the plate 66. In contrast, the lower channel-section members are movable in a direction perpendicular to the longitudinal direction of the channel-section members.

The movement of the lower channel-section members 74 is achieved by mounting them on a block 80. The block 80 is provided with a boss 82 which projects through an elongate aperture 84 in the plate 66. Two threaded portions (not visible) also extend from the block 80 and project through two further elongate apertures 86 in the plate 66. The threaded portions are each provided with a nut 87 which may be tightened or loosened to lock the lower channel-section members in position or to enable adjustment, as necessary.

The adjustment of the lower channel-section members is achieved by passing an elongate threaded bar 88 through a complementarily-threaded aperture 90 in the block boss 82. The axis of the bar 88 is aligned with the longitudinal direction of the elongate apertures 84, 86 in the block, and is rotatably mounted in bearings provided in lugs 92, 94 at the upper and lower portions of the plate 66. The upper end of the bar 88 projects out of the upper lug 92 and is provided with a hexagonal head 96. Thus, by rotating the head 96 and bar 88, the screw-threaded engagement of the bar 88 and the block boss 82 causes the lower channel-section members to move towards or away from the upper channelsection member, as desired.

In use, a cylindrical metal rod (similar to that shown for the first embodiment, but not illustrated in Fig. 3) is passed through and secured in two aligned apertures in lugs positioned towards the top of a bucket to be attached. An identical rod is passed through and secured in two aligned apertures in lugs positioned towards the base of the bucket. The rod 88 of the coupling is then rotated to move the lower channelsection members 74 towards the upper channel-section member 72 with the securing nuts 87 slackened off. The dipper arm and ram arm are then manipulated to locate the upper rod on the bucket within the upper channelsection member 72, and this aided by the outwardlytapering lip 76.When the bar is received within the channel-section member, the dipper and ram arms are then manipulated to move the bucket upwardly, which causes the bucket to pivot about the bar, thus causing the lower channel-section members to lie above the lower bar attached to the bucket. The rod 88 is then rotated (this may be done conveniently by use of a ratchet spanner on the hexagonal head 96) thus causing the lower bar to be seated within the lower channel-section members 74. The nuts 87 are then tightened, and the bucket is then securely and releasably attached to the excavator. The adjustability of the lower-channelsection members allows buckets of different types and sizes to be attached. Removal of the bucket is achieved by the reverse operation of the above.

The invention is not restricted to the details of the foregoing embodiments. For example, although the embodiments have been shown with the channel-section member attached to the excavator, it would be possible to locate the channel-section member (or, for Fig. 3, the upper channel-section member) on the accessory, opening downwardly, which would receive an elongate portion located on the coupling.

Claims

1. An excavator accessory coupling comprising a coupling body having attachment means for connection to a dipper arm and ram arm of an excavator, a first channel-section member, located on one of the coupling body and an excavator accessory, adapted to receive a member secured to the other of the coupling body and the excavating accessory, and a further accessory attachment means, movable to vary its separation from the channel-section member.

2. A coupling as claimed in claim 1, wherein the channel-section member is located above the further accessory attachment means.

3. A coupling as claimed in claim 1 or claim 2, wherein the further accessory attachment means is slidably disposed on the coupling body.

4. A coupling as claimed in any of claims 1 to 3, wherein the further accessory attachment means is provided with an aperture adapted to receive a retaining pin which is connectible to the excavator accessory to be coupled.

5. A coupling as claimed in any of claims 1 to 3, wherein the further accessory attachment means comprises a second channel-section member which is adapted to receive a member secured to the excavator accessory.

6. A coupling as claimed in claim 5, wherein the second channel-section member is adapted to receive an elongate bar.

7. A coupling as claimed in claim 5 or claim 6, wherein the second channel-section member is open in the opposite direction to the first channel-section member.

8. A coupling as claimed in any of claims 4 to 7, wherein the position of the further accessory attachment means is adjustable by means of a screwthreaded rod pivotally mounted with respect to the coupling body and engageable with a complementarily screw-threaded portion of the further accessory attachment means.

9. A coupling as claimed in any of the preceding claims, comprising securing means for securing the further accessory attachment means in a desired position.

10. A coupling as claimed in claim 9, wherein the securing means comprises one or more bolts passing through an aperture in the coupling body into a threaded aperture in the further accessory attachment means.

11. A coupling as claimed in any of the preceding claims, wherein the first channel-section member is located on the coupling body, and the member to be received in the channel-section member is located on the excavator accessory.

12. A coupling as claimed in any of the preceding claims, wherein the member to be received in the channel-section member comprises an elongate bar.

13. An excavator accessory coupling comprising a first portion adapted to be connected to the dipper arm and ram arm of an excavator and a second portion adapted to be secured to an excavator accessory, one of the first and second portions being provided with a first channel-section member adapted to receive a portion of the other of the first and second portions, the coupling further comprising a first securing member located on the first portion adapted to be releasably engageable with a second securing member of the second portion.

14. A coupling as claimed in claim 13, wherein the first securing member is displaceably mounted on the first portion.

15. A coupling as claimed in claim 14, wherein the first securing member is displaceable by power operated means.

16. A coupling as claimed in claim 15, wherein the first securing member is displaceable by means of a fluid-actuated ram.

17. A device as claimed in any of claims 13 to 16, wherein the first securing member on the first portion comprises a latch.

18. A device as claimed in any of claims 13 to 17, wherein the second securing member of the second portion comprises a lug.

19. A coupling as claimed in claim 18, wherein, in use, the lug on the second portion projects through an aperture in the first portion.

20. A coupling as claimed in claim 13 or claim 14, wherein the first securing member also comprises a channel-section member.

21. A coupling as claimed in claim 20, wherein the channel-section member is open in the opposite direction to the first channel-section member.

22. A coupling as claimed in claim 20 or claim 21, wherein the second channel section member is displaceable by means of a screw-threaded rod pivotally mounted on the first portion and engageable with a complementarily screw-threaded portion of the second channel-section member.

23. A coupling as claimed in any of claims 20 to 22, wherein the second securing member comprises a rod or bar attached to the accessory.

24. A coupling as claimed in any of claims 14 to 23, wherein the first channel-section member is provided on the first portion.

25. A coupling as claimed in any of claims 14 to 23, wherein the first channel section member is provided on the second portion.

26. An excavator accessory coupling substantially as herein described, with reference to, and as illustrated in, the accompanying drawings.