GB2209149A - Excavator bucket - Google Patents

Abstract

An excavator bucket comprises an open-fronted body member (2) having a base region which includes a transverse plate portion (14) to which are attached a plurality of teeth (16), a transverse blade portion (20) rearwardly of the plate portion (14) and extending downwardly and forwardly of the base region (4), and a slot (18) defined in the base region (4) between the blade portion (20) and the plate portion (14) whereby the blade portion (20) can be used to level off the surface of ground under treatment accurately and to feed loose particulate material from said surface through the slot (18) and into the body member (2). <IMAGE>

Description

IMPROVED EXCAVATOR BUCKET This invention relates to excavator buckets.

Excavators are commonly used to remove and prepare ground for subsequent treatment, the removal and/or replacement of material being effected by means of a hydraulicallycontrolled excavator bucket mounted on the free end of a boom or jib on the excavator.

Excavator buckets commonly comprise an open-fronted body member having a base plate or adaptor plate to the front of which are mounted a plurality of teeth, said teeth being present to enable penetration of the bucket into hard ground.

However, it is often necessary, once the basic digging operation has been completed, to remove the teeth-marks and loose material left by the bucket thereby to leave a level, clean-cut finish to the ground.

It is known to provide a bucket in which the teeth are removable from the base plate thereof to enable the levell ing process to be carried out. However this removal of the teeth can be a difficult and time-consuming exercise, the bolts securing the teeth to the bucket normally being damaged such that they require replacement once removed.

In the case of excavator buckets in which the teeth are welded to the base plate or adaptor plate of the bucket and cannot therefore be removed therefrom, it would be possible to provide an extra bucket having a flat cutting edge thereto. However this adds considerably to the expense of the machinery, particularly bearing in mind the numerous different shapes and sizes of toothed buckets currently available each of which would require its own straight-edged substitute bucket.

It would be desirable to be able to provide an excavator bucket capable of both digging hard ground and providing a level, clean-cut finish to the ground without the aforementioned disadvantages of the known arrangements.

According to the present invention there is provided an excavator bucket comprising an open-fronted body member having a base region thereto, said base region including a plate portion extending transversely of the bucket and a plurality of teeth secured to said plate portion to project forwardly therefrom, characterised in that the base region of the body member further includes, rearwardly of said plate portion, a transverse blade portion extending downwardly and forwardly of said base region, a transverse slot being defined in the base region of the body member between the blade portion and the plate portion.

With such an arrangement, the bucket can be used in the conventional manner for digging purposes, the teeth displacing the material into the body member for subsequent removal or displacement. When it is desired to finish off the surface of a previously-dug area, however, the bucket is tipped slightly to locate the teeth thereof just above the surface with the leading edge of the blade portion engaging said surface. Thus, forward movement of the bucket will result in the blade portion levelling the surface of the ground and collecting loose material in front thereof, subsequent manoeuvring of the bucket resulting in loose material being fed by the blade portion through the transverse slot and into the body member.

Preferably, with the base region of the body member located substantially horizontally, the free edge of the blade portion extends downwardly just below the level of the base of the teeth.

The blade portion may be permanently secured to the body member, for example by welding, or may be releasably and reversibly attached to said bod member.

Conveniently the blade portion makes an angle of between 0 450 and 70 with the horizontal with the bucket in its normal rest position.

By way of example only, an embodiment of the invention will now be described in greater detail with reference to the accompanying drawings of which: Fig. 1 is a vertical section through an excavator bucket according to the invention, and Fig. 2 is a perspective view from the front and one side of part of the bucket of Fig. 1.

Referring to the drawings, the illustrated bucket comprises an open-fronted body member indicated generally at 2 and including a base region 4, a backwall 6, a topwall 8 and a pair of sidewalls 10,12.

The backwall, topwall and sidewalls are of relatively conventional shape and construction, the novelty of the illustrated bucket lying in the configuration of the base region 4.

More particularly, the base region 4 includes, at the front thereof, a base plate or adaptor plate 14 extending transversely the full width of the body member 2, the ends of the plate 14 being secured to the sidewalls 10,12.

Welded to the adaptor plate 14 are a plurality of teeth 16 again of substantially conventional shape spaced along the length of the plate 14, said teeth 16 projecting forwardly from the plate 14 and beyond the open front of the body member 2.

Defined in the base region 4, rearwardly of the plate 14, is a slot 18 extending the full width of the body member, the rear edge of the plate 14 forming the front edge of said slot 18 and the rear edge of the slot being defined by the front face of a rigid blade 20 welded to the body member 2 as best seen in Fig. 1.

More particularly, the blade 20 extends transversely the full width of the base region 4 of the bucket and extends downwardly from the bucket to a level just below that of the base of the teeth 16. The illustrated blade makes an angle of about 700 with the plane of the base region 4 of the bucket, but this angle may lie anywhere within the range of, typically, 450 to 700.

The slot may be, typically,l5cms to 20cms wide compared with a length of, typically, 60cms for a conventional trenching bucket.

The described bucket can be used for excavation purposes in the normal manner with the teeth 16 digging into any hard ground and loose material being fed into the body member 2 by appropriate manoeuvring of the bucket by the operator. The presence of the slot 18 has little, if any, effect during normal excavation and transportation of the material.

On completion of major excavation and/or when it is desired to provide a satisfactory, clean-cut surface at an accurate predetermined level to the ground, the described bucket can be used to achieve this as follows.

With the bucket so positioned that the teeth 16 are located just above the ground and the blade 20 is located with its free, cutting edge engaging the ground, the bucket is moved forwards whereby loose material is collected in front of the angled blade 20 and any surface irregularities such as those left by the teeth 16 are removed by the blade 20 which leaves behind it alevel, clean-cut finish to the ground. The bucket is periodically tilted whereby the blade 20 feeds the loose material so collected in front thereof through the slot 18 and into the body member 2 for subsequent disposal.

The blade 20 thus enables the removal of particulate material from the ground and also permits controlled scraping of the ground to an accurate desired working level, the nature of the invention being such as to enhance considerably the operator's tolerances compared with existing arrangements.

Although the blade 20 is shown and described as projecting below the level of the teeth 16, the blade may terminate above this level in which case the scraping and levelling of the surface in question can still be effected but with the bucket tilted slightly further from its normal working position and whereby the teeth 16 are clear of the ground.

Clearly the accuracy of the finished surface will depend upon the skill of the operator, but the multipurpose nature of the bucket is such that no alteration or modification thereto is required to enable the operator to progress from the excavation process to the finishing-off process.

As well as having application on construction sites, the described bucket is ideal for open-cast sites in which the bulk of the over-burden can be removed using the teeth 16 and the loose material remaining can then be removed in a finely controlled manner using the blade 20 to reveal the surface of the coal seam for subsequent working and without changing over the bucket or removing the teeth as is currently necessary.

The depth of the blade 20 is chosen to suit particular requirements and, as mentioned above, may or may not project below the level of the teeth 16. The blade 20 may be permanently welded to the bucket or may be removably bolted thereto. In the latter case, the blade 20 could be replaced when worn out, or could be constructed to be of a reversible nature such that, when one edge is worn out, the blade is reversed to introduce a fresh cutting edge thereto.

The slot 18 may be created by cutting away the front and two side edges of part of the continubus base region of a bucket and bending this cut-away portion downwardly to form a backing plate to which the blade 20 can subsequently be attached, removably or otherwise. Strengtheners can be welded or otherwise secured to the blade 20 as necessary.

Claims (5)

1. !. An excavator bucket comprising an open-fronted body member having a base region thereto, said base region including a plate portion extending transversely of the bucket and a plurality of teeth secured to said plate portion to project forwardly therefrom, characterised in that the base region of the body member further includes, rearwardly of said plate portion, a transverse blade portion extending downwardly and forwardly of said base region, a transverse slot being defined in the base region of the body member between the blade portion and the plate portion.
2. 2. An excavator bucket as claimed in claim 1 in which the free edge of the blade portion projects just beyond the level of the base of the teeth.
3. 3. An excavator bucket as claimed in claim 1 or claim 2 in which the blade portion is releasably and reversibly attached to the body member.
4. 4. An excavator bucket as claimed in any one of claims 1 to 3 in which the blade portion makes an angle of between 450 and 700 with the plane of the base region of the body member.
5. 5. An excavator bucket substantially as described with reference to and as illustrated by the accompanying drawings.