GB2413544A

GB2413544A - Combined bucket and grab assembly

Info

Publication number: GB2413544A
Application number: GB0508383A
Authority: GB
Inventors: James Lyons
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-04-27
Filing date: 2005-04-26
Publication date: 2005-11-02
Also published as: GB0508383D0

Abstract

The invention relates to an excavator bucket assembly (10) which is adapted for use in a conventional digging capacity, but which is also capable of being used as a grab or claw, with particular application in the field of erecting telegraph poles, wherein the bucket assembly (10) may first be used to excavate the hole or trench into which the pole is to be inserted, and then used in the grab capacity to lift and insert the pole into position within the hole or trench, the dual functionality being realised by the use of a pair of hinged arms (16,18) which may be displaced relative to one another.

Description

24 1 3544 "An Excavator Bucket Assembly" The present invention is

concerned with a bucket assembly, and in particular a bucket assembly for connection to an excavator vehicle or the like.

When erecting poles, for example telegraph poles or the like, a number of sequential operations must be carried out for each pole, which operations are time consuming and labour intensive. Initially, a hole or trench must be dug with suitable excavating equipment, generally a hydraulically powered excavating bucket or the like. Each pole must then be lifted into a vertical position, and seated within the hole. The hole is then back filled and compacted in order to secure the pole in place.

Although an excavator with a bucket attachment may be used for the digging and back filling of the holes, separate provisions must be made for lifting and transporting the actual poles. This may be achieved using a separate vehicle with a suitable grab, although in practice it is more usual for the bucket attachment to be removed from the excavator, and a grab attachment connected in place of same. Obviously the necessity to change attachments greatly increases the time taken to complete the work, as the bucket attachment must first be connected in order to dig the necessary holes, and must then be removed in order to allow the connection of a grab attachment. The grab attachment can then be used to lift and transport the poles into the various holes. Once this step has been completed, the grab attachment must then be removed, and the bucket attachment re-connected, in order to allow back filling of the various holes.

It is therefore an object of the present invention to mitigate the above mentioned problems of the prior art.

The present invention therefore provides an excavator bucket assembly comprising a pair of arms hingedly mounted relative to one another; and articulation means operable to displace the pair of arms between a first position in which the arms abut one another to define a cavity therebetween, and a second position in which the arms are separated from one another.

Preferably, the cavity is open at opposed ends to allow an elongate component to project from either end of the cavity when such a component is being held between the arms.

Preferably, the cavity extends from one open end to the other open end in a direction substantially perpendicular to the direction in which the arms are Misplacable.

Preferably, the bucket assembly comprises a body housing the articulation means, to which body the pair of arms are hingedly mounted along respective axes.

Preferably, each arm is substantially L shaped in cross- section, comprising a wall portion and a base portion projecting substantially perpendicularly therefrom, the base portion of adjacent arms abutting when the arms are in the first position.

Preferably, each arm is hingedly mounted to the body via the respective wall portion.

Preferably, one arm extends beyond the respective axis to define a lug on which the articulation means acts in order to effect displacement of the arms relative to one another.

Preferably, the articulation means comprises a link mounted between the lug and the opposed arm, at a position on the opposed arm between the axis and the base portion thereof.

Preferably, the articulation means comprises an actuator mounted at one end to the body and at an opposed end to the lug.

Preferably, the lug is housed within the body.

Preferably, the actuator comprises a fluid powered ram.

Preferably, the lever ratio of the lug and the respective arm is at least 1:1, and preferably 1:3, such that a given displacement of the lug will result in an equal or magnified displacement of the arms.

Preferably, each arm includes a plurality of reinforcing webs extending between the wall portion and the base portion.

Preferably, the bucket assembly comprises a coupling enabling the releasable engagement of the bucket assembly to an excavating vehicle or the like.

The present invention will now be described with references to the accompanying drawings, in which; Figure 1 illustrates a perspective view of a bucket assembly according to the present invention, in which a pair of arms thereof are in a first closed position; Figure 2 illustrates an end view of the bucket assembly of figure 1, in which the pair of arms are in a second open position, and in which articulation means are exposed for illustrative purposes; Figure 3 illustrates a perspective partially sectioned view of the bucket assembly of the present invention; and Figure 4 illustrates a sectioned side elevation of the bucket assembly of the invention.

Referring now to the accompanying drawings, there is illustrated a bucket assembly, generally indicated as 10, which is capable of both conventional digging operations, in addition to grabbing and lifting elongate items such as poles (not shown) or the like, as will be described hereinafter in detail.

The assembly 10 is primarily intended for use at the end of an articulated arm (not shown) of an excavator (not shown) or the like, and thus the preferred embodiment illustrated is provided with a coupling 12 mounted to a body 14 of the assembly 10. The coupling 12 enables the assembly 10 to be releasably engaged to such an articulated arm in conventional fashion. It will of course be appreciated that the coupling 12 could be replaced with any other suitable form of coupling (not shown), depending on what type of machinery the assembly is to be mounted. In the preferred embodiment illustrated, the coupling 12 is of the conventional quick hitch type.

Hingedly mounted to the body 14 is a first arm 16 and a second arm 18, which is effectively a mirror image of the first arm 16. The first arm 16 is hingedly mounted to the body 12 along an axis defined by a first hinge 20, while the second arm 18 is hingedly mounted to the body 14 along an axis defined by a second hinge 22. The hinged mounting of the first arm 16 and the second arm 18 facilitates the displacement of the arms 16, 18 relative to one another, between a first position as illustrated in figure 1, in which the arms 16, 18 abut against one another, to a second position as illustrated in figure 2, in which the arms are displaced outwardly from one another, as will be described hereinafter in detail. In order to effect this displacement, the assembly 10 is provided with articulation means in the form of a hydraulic ram 24, the configuration and operation of which will again be described hereinafter in detail.

Each arm 16, 18 comprises a wall portion 26 and a base portion 28 projecting substantially perpendicularly therefrom. The arms 16, 18 are shaped and dimensioned such that when in the first position as illustrated in figure 1, the assembly 10 is substantially bucket shaped, whereby a cavity is defined between the pair of arms 16, 18, which may then be employed in this configuration to dig/remove earth or the like, in conventional fashion. To this end, each base portion 28 is provided with a plurality of teeth 30 at the front end thereof, the array of teeth 30 defining a front or cutting edge of the bucket assembly 10.

Each arm 16, 18 is also provided with a plurality of webs 32 evenly spaced along the length thereof, which webs 32 ensure that the digging strength of a conventional bucket (not shown) is maintained, despite the split nature of the assembly 10. The assembly 10 does differ from conventional buckets in that the rear end of the cavity defined by the pair of arms 16, 18 is also open, thereby allowing the assembly 10 to dig earth in both a forward and rearward direction. The open ended nature of the cavity defined between the pair of arms 16, 18 also enables the assembly 10 to grip and retain elongate components such as telegraph poles (not shown) or the like, which can project from either end of the cavity when being held between the arms 16, 18, as will be described in greater detail hereinafter. The underside of the assembly 10, as defined by the pair of base portions 28, is substantially flat in order to allow the assembly 10 to be used for compacting earth or the like. Thus the operation of the assembly 10 in its earth digging capacity is wholly conventional.

However, as described above, the assembly 10 is also capable of operating in the manner of a grab or claw, as clearly illustrated in figure 2, whereby the arms 16, 18 may be articulated relative to one another in order to allow items such as poles or the like to be gripped and manoeuvred as required. The pair of arms 16, 18 may be opened into the position illustrated in figure 2, as will be described in detail hereinafter, and then advanced about a telegraph pole (not shown) or the like, and then closed back into the configuration illustrated in figure 1. The pole is therefore located and gripped between the arms 16, 18. The open ended cavity defined by the arms 16, 18 when closed, allows such a pole to project out of either end of the cavity, thereby allowing the arms 16, 18 to fully or substantially fully close when gripping such an object. This feature provides added security when lifting and manocuvring poles or the like, as the pair of base portions 28 are closed together beneath the pole, such that the arms 16, 18 essentially circumscribe the pole. This prevents the pole from dropping out of the assembly 10 were the grip effected by the arms 16, 18, and in particular the webs 32, to become insufficient, for whatever reason, to lock or fix the pole in position between the arms 16, 18.

In order to effect the displacement of the arms 16, 18 relative to one another, the first arm 16 is provided with a pair of lugs 34 which project beyond the first hinge 20, on which lugs 34 the hydraulic ram 24 acts. The hydraulic ram 24 is mounted, at one end thereof, to the lugs 34 by means of a first anchor 36, which in the embodiment illustrated is a basic shaft and bush type bearing. It will of course be appreciated that any other suitable form of coupling (not shown) could be used. The hydraulic ram 24 is mounted, at the opposed end thereof, to the body 14, adjacent the second hinge 22. This end of the hydraulic ram 24 is hingedly mounted to the body 14, in order to allow slight pivoting of the hydraulic ram 24 during the compression and extension thereof.

Thus it will be appreciated that compression of the hydraulic ram 24 will force the first arm 16 outwardly, while extension of the ram 24 will force the first arm 16 inwardly towards the second arm 18. In order to generate sufficient force during both the compression and extension strokes, the ram 24 is preferably a double acting ram. A pair of single acting rams (not shown) could be used, but this would result in a bulkier and more complex construction. It will also be appreciated that any other mechanical equivalent could be used in place of the ram 24, which is capable of extending and retracting to exert the requisite force on the first arm 16. For example, the ram 24 could be replaced with a rack and pinion based mechanism (not shown), or a motor driven rotary to linear transducer arrangement (not shown).

In order to effect the simultaneous displacement of the second arm 18, the articulation means further comprises a rigid link 38 mounted between the lugs 34 and the second arm 18, as can be seen in figures 2 and 3. The link 38 is mounted to the pair of lugs 34 by a second anchor 40, which is again of the shaft and bush type, and is located beneath the first anchor 36. The opposed end of the link 38 is mounted to the second arm 18, beneath the second hinge 22, by means of a third anchor 42, which is of the shaft and bush type. Therefore, during compression of the ram 24, the lugs 34 are hinged inwardly about the first hinge 20, thereby forcing the link 38 against the second arm 18, beneath the second hinge 22, thus forcing the second arm 18 to simultaneously hinge outwardly.

Conversely, upon extension of the ram 24, the lugs 34 are hinged outwardly, causing the link 38 to pull against the second arm 18, forcing same to hinge closed against the first arm 16.

It will therefore be appreciated that the link 38 enables the single hydraulic ram 24 to effect the simultaneous displacement of the arms 16, 18, thus allowing an extremely compact design. This is beneficial in allowing the moving parts, namely the ram 24, lugs 34 and link 38 to be housed entirely within the body 14, thus being shielded from dirt and damage during use of the assembly 10. The compact nature of the design also allows the width of the assembly 10 to be kept to a minimum, thereby allowing the assembly 10 to dig relatively narrow holes or trenches, which are best suited for erecting poles or the like. To this end, it is preferable, as in the preferred embodiment illustrated, that the ram 24 is mounted at an angle across the body 14, thereby allowing the width of the body 14 to be kept below the full length of the ram 24.

In addition, the ratio of the distance between the first hinge 20 and the first anchor 36, which is essentially the length of the lugs 34, and the distance between the first hinge 20 and the base portion 28 of the first arm 16, results in a lever affect. Therefore, a relatively small displacement of the lugs 34 is required in order to effect a suitable displacement of the pair of arms 16, 18. This allows the ram 24 to have a short stroke, allowing a further reduction in the width of the body 14, and thus the width of holes/trenches which the assembly 10 is capable of excavating.

It will be appreciated that when picking up poles or the like with the assembly 10, the plurality of webs 32 will act as gripping means, providing a secure grip on objects clamped between the pair of arms 16, 18. However, the assembly 10 is also preferably provided with a foot 44 mounted in a corresponding bracket 46 on the front face of the body 14. The foot 44 is secured within the bracket 46 by means of a pin 48, which may be seated in any one of a number of corresponding apertures in the foot 44, thereby allowing the depth to which the foot 44 projects to be varied. Thus, when a pole having a relatively small diameter is to be gripped by the assembly 10, the foot 44 can be lowered considerably into the cavity defined by the pair of arms 16, 18, in order to press against the pole when gripped therebetween. The foot 44 therefore acts to further secure an object gripped between the pair of arms 16, 18.

The assembly 10 is preferably provided with a chain 50 releasably securable to the body 14 via a number of holes provided, which chain 50 acts as a secondary or backup safety feature, preventing a pole from falling from the assembly 10 in the event of mechanical/hydraulic failure.

Once a pole has been grabbed by the assembly 10, the chain is uncoupled from the body 14 at one end, passed beneath the pole, and reconnected to the body 14. Thus, in the event of a mechanical/hydraulic failure in the assembly 10, the chain 50 will catch and hold the pole in place.

The chain 50 does still however allow the assembly 10 to be slid down the length of a pole, once secured vertically, in order to allow the chain 50 to be manually disconnected, at one end, from the body 14, in order to allow the assembly 10 to be separated from the pole.

The present invention therefore provides a bucket assembly which allows conventional digging operations to be undertaken, in addition to allowing elongate objects such as telegraph poles or the like to be gripped and transported, in particular when erecting such poles.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features

disclosed in this specification (including any

accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

Claims 1. An excavator bucket assembly comprising a pair of arms hingedly

mounted relative to one another; and articulation means operable to displace the pair of arms between a first position in which the arms abut one another to define a cavity therebetween, and a second position in which the arms are separated from one another.
2. An excavator bucket assembly according to claim 1 in which the cavity is open at opposed ends to allow an elongate component to project from either end of the cavity when such a component is being held between the arms.
3. An excavator bucket assembly according to claim 2 in which the cavity extends from one open end to the other open end in a direction substantially perpendicular to the direction in which the arms are Misplacable.
4. An excavator bucket assembly according to any preceding claim comprising a body housing the articulation means, to which body the pair of arms are hingedly mounted along respective axes.
5. An excavator bucket assembly according to any preceding claim in which each arm is substantially L shaped in cross-section, comprising a wall portion and a base portion projecting substantially perpendicularly therefrom, the base portion of adjacent arms abutting when the arms are in the first position.
6. An excavator bucket assembly according to claim 5 in which each arm is hingedly mounted to the body via the respective wall portion.
7. An excavator bucket assembly according to any of claims 4 to 6 in which one arm extends beyond the respective axis to define a lug on which the articulation means acts in order to effect displacement of the arms relative to one another.
8. An excavator bucket assembly according to claim 7 in which the articulation means comprises a link mounted between the lug and the opposed arm, at a position on the opposed arm between the axis and the base portion thereof.
9. An excavator bucket according to claim 7 or 8 in which the articulation means comprises an actuator mounted at one end to the body and at an opposed end to the lug.
10. An excavator bucket assembly according to any of claims 7 to 9 in which the lug is housed within the body.
11. An excavator bucket assembly according claim 9 or in which the actuator comprises a fluid powered ram.
12. An excavator bucket assembly according to any of claims 7 to 11 in which the lever ratio of the lug and the respective arm is at least 1:1, and preferably 1:3, such that a given displacement of the lug will result in an equal or magnified displacement of the arms.
13. An excavator bucket assembly according to any of claims 5 to 12 in which each arm includes a plurality of reinforcing webs extending between the wall portion and the base portion.
14. An excavator bucket assembly according to any preceding claim comprising a coupling enabling the releasable engagement of the bucket to an excavating vehicle or the like.