IES940183A2 - Excavator bucket - Google Patents

Abstract

An excavator bucket includes a hollow top stiffener which is of integral construction and which is simpler to manufacture and lighter in weight than a traditional hollow excavator bucket top stiffener. Gussets for transmitting stress from the top stiffener to the side walls are of modified wedge shape so as to better transmit the stress and so as to facilitate flow of material into and out of the bucket.

Description

EXCAVATOR BUCKET The present invention relates to excavator buckets.

In use of an excavator bucket, the top stiffener of the bucket is subject to considerable stress. It is the top stiffener which is attached by means of brackets to the lift arms of the prime mover used to operate the bucket. When the bucket is full and the lift arms are slewed from side to side, the top stiffener is subject to very large stresses. When digging large torsional and bending forces are induced on the top stiffener by the action of the prime mover on the excavator bucket.

A traditional excavator bucket is provided with a reinforced top stiffener so as to cope with the stresses. A substantially flat top stiffener is reinforced by attaching thereto an additional member which is channel shaped in profile as seen from the side of the bucket. The result is a top stiffener which is generally rectangular in profile as seen from the side of the bucket. This construction is considerably stronger than a simple flat top stiffener. This construction is manufactured by cutting the flat top stiffener, cutting the channel shaped reinforcing member, and then manually welding the two parts - 2 5 4 0 ΐ η j ν together to form the reinforced top stiffener.

A traditional excavator bucket can also be provided with a pair of side gussets within the bucket connecting the underside of the top stiffener to each side wall so as to cater for stresses induced due to the slew action of the prime mover, in particular to distribute stress from the top stiffener to the side walls. Each gusset is essentially wedge shaped, that is to say the gusset has a triangular profile as viewed from the front looking into the open mouth of the bucket, and has a rectangular profile as viewed from one side of the bucket.

In accordance with a first aspect, the invention provides an excavator bucket including a hollow top stiffener, characterised in that the top stiffener is of integral construction.

Preferably, the top stiffener is made from a sheet of material folded back onto itself.

In accordance with a second aspect, the invention provides an excavator bucket including a gusset for distributing stresses from the top stiffener to the side wall, the gusset being generally wedge shaped, characterised in that the gusset has a modified triangular profile as viewed from the front looking into the open mouth of the bucket, the modification being that the hypotenuse of the triangle is concave, and further characterised in that the gusset has a modified rectangular profile as seen from the side of the excavator, the modification comprising flaring or tapering towards the front and towards the back of the bucket.

According to a particularly advantageous feature the invention provides an excavator bucket including a reinforced top stiffener and a pair of gussets one each between the top stiffener and each side wall, characterised in that the top stiffener is an integral top stiffener in accordance with the first aspect of the invention, and the gussets are of modified wedge shape in accordance with the second aspect of the invention.

The reinforced top stiffener and gussets according to the 940183 - 3 invention offer many advantages. The reinforced top stiffener according to the invention is stronger than a traditional reinforced top stiffener of the same material. The gussets according to the invention are stronger than the traditional gussets of the same material, in particular the continuously curved profile better transmits stress from the top stiffener to the sidewalls. By using the reinforced top stiffener and gussets according to the invention, it is possible to employ thinner gauge top stiffener material than has heretofore been possible, thereby reducing the weight of the top stiffener by up to one quarter, and the overall weight of the bucket by up to ten percent. This reduction greatly reduces shipping costs bearing in mind that excavator buckets may weigh one tonne or more. Also, the swept profile of the reinforced top stiffener of the invention is more asthetically pleasing than the traditional rectangular profile top stiffener. Furthermore, the top stiffener is simpler to manufacture, involving cutting one piece of sheet material instead of cutting two pieces, and joining the edge of the folded back piece of sheet material to the body of the sheet material by means of a single straight line automatic weld whereas the traditional method involved joining the two pieces by means of a rectangular manual weld. The tapered profile of the gussets allows material to flow more easily into and out of the excavator bucket and prevents clogging within the bucket. Other advantages may become apparent from the description which follows.

The invention will now be described in more detail with reference to the accompanying drawings which show, by way of example only, one construction of excavator bucket in accordance with the invention. In the description which follows front view means a view looking into the open mouth of the bucket when the bucket is freestanding and upright. In the drawings: Figure 1 is a front perspective view of an excavator bucket including a top stiffener and gussets according to the invention; Figures 2, 3 and 4 are front perspective, rear and side views of a top stiffener according to the invention, and 0 1 8 3^1 - 4 Figures 5, 6 and 7 are front perspective, front and side views of a gusset according to the invention.

Referring initially to Figure 1, the bucket comprises two side walls 1, 2, a curved floor 3, a top stiffener generally designated 4, a pair of brackets 5, 6 attached to the top stiffener and gussets 7 and 8 (the latter shown in broken lines) between the underside of the top stiffener 4 and side walls 1, 2. In use, the front lift arms of an agricultural tractor or other prime mover (not shown) are connected to the brackets 5, 6 and are used to raise and lower the bucket and to move the bucket from side to side. A hydraulic ram (not shown) is used to tilt the bucket about the horizontal axis of the brackets 5, 6.

Referring now to Figures 2, 3 and 4, the top stiffener generally designated 4 comprises a single sheet of metal which is folded over to provide an approximately tubular top stiffener. The free edge 9 of the folded over part 4a of the top stiffener 4 is joined to the rearwardly extending part 4b of the top stiffener 4 by means of a single straight line weld 10. The weld 10 is in a straight line and may be easily applied by means of an automatic welding machine. Thereafter, the top stiffener 4 is joined to the side walls 12 and to the curved floor 3 by means of manual welding. The brackets 5, 6 are then attached to the top stiffener 4. It will be appreciated that the tubular construction is extremely strong, and that accordingly a thinner gauge of material may be used than is used in the top stiffener of a traditional reinforced excavator bucket.

Referring now to Figures 5, 6 and 7, the gusset 7 comprises a leading wall 20, a trailing wall 21, and a sloped load bearing wall 22. In accordance with the invention the sloped load bearing wall 22 is concave in shape, and this concave shape provides a better transmission of the stress forces between the top stiffener 4 and the side wall 1. Also, in accordance with the invention, the leading wall 20 and trailing wall 21 are tapered, and this allows material such as earth to flow into the excavator bucket and to flow back out again more readily than was the case with the traditional non-tapered walls which had a tendency to block the passage of material, for example trapping a substantial body of wet earth within the excavator bucket.

Claims (5)

CLAIMS 94 0 1 8 3^1

1. An excavator bucket including a hollow top stiffener, characterised in that the top stiffener is of integral construction.

2. An excavator bucket according to claim 1 in which the top stiffener is made from a sheet of material folded back onto itself.

3. An excavator bucket including a gusset for distributing stresses from the top stiffener to the side wall, the gusset being generally wedge shaped, characterised in that the gusset has a modified triangular profile as viewed from the front looking into the open mouth of the bucket, the modification being that the hypotenuse of the triangle is concave, and further characterised in that the gusset has a modified rectangular profile as seen from the side of the excavator, the modification comprising flaring or tapering towards the front and towards the back of the bucket.

4. An excavator bucket in accordance with claim 1 and claim 3.

5. An excavator bucket substantially as herein described with reference to and as shown in the accompanying drawings.