The invention relates to an attachment for a bucket front which constitutes a wear part in an digging bucket, the digging bucket comprising side portions forming cou- pling portions between the digging bucket and the bucket front, each side portion comprising an abutment surface facing a sliding surface of the bucket front, there be- ing several first cut-outs extending from the abutment surface into the side portion, and a bolt hole extending from a front face of each side portion and through the cou- pling portion transversely to the longitudinal direction of said first cut-outs.

By a digging bucket is meant, in this connection, any form of bucket for digging or loading, for example an excavator bucket or a front-loader bucket.

A front piece of a digging bucket is subjected to considerable wear. Even though the front piece may be provided with wear strips or similar protective elements that are designed to extend the life of the front piece, it is necessary at irregular intervals to replace the front piece. US patent 4550512 discloses a bucket in which the bucket front is provided with pro- jecting tangs extending into side attachments and a bottom attachment formed as cut-outs in the side walls and bottom of the bucket. The bucket front is locked into the side attachments by means of screws extending through the side walls and the side tangs of the bucket front. The screws are utilized relatively poorly, as only two shear areas are subjected to load.

US 2005/0172524 A1 describes a bucket front with replaceable, cast wear parts bolted to a front plate with at least one screw that sits in recesses in the wear part. Each end of the front plate is provided with a vertical end piece that encloses an attachment portion projecting from the front edge of each side wall of the bucket and being weld- ed to said edge. The connections between the front plate and the attachment portions are secured with screws and nuts extending transversely to the working direction of the bucket through the end pieces and the attachment portions and being recessed

P28218PC00 description and claims into the end pieces.

Systems have been developed for replacing laborious and costly welding operations in the replacing of front pieces on a digging bucket. From the applicant's own NO patent 333294, an attachment for a bucket front is known, the digging bucket comprising side portions that are formed with coupling pieces, the coupling pieces and the bucket front being connected by means of locking bolts extending through openings in the coupling pieces and in the bucket front, the coupling piece comprising at least two projections that fit complementarily into cut-outs in the bucket front, and the locking bolts extending through openings in the projections of the coupling pieces and in the bucket front.

The invention has for its object to remedy or reduce at least one of the drawbacks of the prior art or at least provide a useful alternative to the prior art. It is an object of the invention to simplify the screw-free attachment principle described in NO 333294.

The object is achieved through the features that are specified in the description below and in the claims that follow.

An attachment for a bucket front which constitutes a wear part in a digging bucket has been provided, the digging bucket comprising side portions forming coupling portions between the digging bucket and the bucket front. Each side portion includes an abut- ment surface facing a sliding surface of the bucket front. From the abutment surface, several first cut-outs extend into the side portion. A bolt hole extends from a front face of the side portion and through the coupling portion transversely to the longitudi- nal direction of the cut-outs. Each cut-out is preferably provided with a bevelled mouth portion.

The bucket front is provided with through second cut-outs that correspond with the cut-outs in the side portions. The cut-outs of the bucket front are arranged to receive coupling pins extending through the bucket front, up from said sliding surface and into the cut-outs of the side portions. Each coupling pin is provided with a projecting first end portion which can be accommodated in countersunk mouth portions of the cut- outs of the bucket front. A second end portion of the coupling pin is provided with a transverse bolt hole which, when the bucket front is abutting against the abutment surfaces of the side portions and the coupling pin has been inserted through the buck- et front into the cut-out of the respective side portion, is in line with the bolt hole through the coupling portion of the side portion, in order thereby to enable attachment of the bucket front to the side portion by an attachment bolt being inserted through

P28218PC00 description and claims the corresponding bolt holes. Thereby the bucket front can be attached to the bucket without any screwing.

In a preferred embodiment, the coupling pin has a rectangular or square cross section. In a preferred embodiment the cross section of the coupling pin is rectangular. The first end portion may be projecting at least at two opposite side edges, preferably with abutment surfaces falling in an outward slope towards a side edge, with an angle of slope typically in the order of 40-50°. An advantage of this is that it is easier to orient the coupling pins with the correct direction of the transverse bolt holes. In another embodiment, the abutment surface is conical.

In one embodiment the bucket front projects outwards from outward-facing side faces of the respective side portions. The advantage of this is that the side edges of the bucket front may thereby be subjected to greater wear before the coupling pins lose their lateral support in the cut-outs in the bucket front.

The invention is defined by the independent claim. The dependent claims define ad- vantageous embodiments of the invention.

The invention relates, more specifically, to an attachment for a bucket front that con- stitutes a wear part in a digging bucket, the digging bucket comprising side portions forming coupling portions between the digging bucket and the bucket front, wherein each side portion comprises an abutment surface facing a sliding surface of the bucket front,

several first cut-outs extend from the abutment surface into the side portion, and

a bolt hole extends from a front face of each side portion and through the cou- pling portion transversely to the longitudinal direction of said first cut-outs, character- ized by

the bucket front being provided with several through second cut-outs corre- sponding with the first cut-outs of the side portions to receive coupling pins that are arranged to extend through the bucket front, up from said sliding surface and into the cut-outs of the side portions,

each coupling pin being provided with a projecting first end portion and a sec- ond end portion provided with a transverse bolt hole,

the cut-outs of the bucket front being provided with countersunk mouth por- tions arranged to accommodate the projecting first end portions of the coupling pins, and

the transverse bolt hole of each coupling pin, when the bucket front is abutting

P28218PC00 description and claims against the abutment surfaces of the side portions and the coupling pins have been inserted through the bucket front and into the cut-outs of the respective side portion, being in line with the bolt hole through the coupling portion of the respective side por- tion, in order thereby to be able to receive an attachment bolt. The cut-outs of the side portion may be provided with bevelled mouth portions. This simplifies the insertion of the coupling pins into the coupling portion when the bucket front is not positioned accurately relative to the coupling portion.

The coupling pins may have a rectangular cross section. An advantage of this is that the bolt holes of the coupling pins will always be oriented correctly by insertion into the cut-outs.

The projecting first end portions of the coupling pins may be projecting with one or more abutment surfaces falling in an outward slope with an angle of slope in the order of 40-50°. Alternatively, the projecting first end portions of the coupling pins may be projecting with a conical abutment surface falling in an outward slope with an angle of slope in the order of 40-50°.

End portions of the bucket front may project outwards from outward-facing side faces of the respective side portions. This reduces the wear on the coupling portions.

A bolt-hole extension may extend from an edge face opposite the front face of the side portion and into the bolt hole. An advantage of this is that the attachment bolt may be loosened with simple means, for example a hammer and a punch.

In what follows, an example of a preferred embodiment is described, which is visual- ized in the accompanying drawings, in which :

Figure 1 shows, in perspective, a digging bucket with a bucket-front attachment according to the invention; Figure 2 shows, on a larger scale, a section of an exploded perspective drawing of the digging bucket with the attachment elements and the bucket front; and

Figure 3 shows, on a larger scale, a cross section through a portion of a bucket side, in which the bucket front is attached according to the invention, and in which, for the sake of exposure, only one coupling pin is shown.

Reference is first made to figure 1, in which the reference numeral 1 indicates a dig-

P28218PC00 description and claims ging bucket provided with a bucket bottom 11 which bends upwards, a bucket front 12 and two bucket sides 13 defining the digging bucket 1 sideways. The bucket front 12 forms a sliding surface 121 which forms an extension of an internal bottom surface 111 of the bucket bottom 11. The bucket sides 13 are provided with side portions 14 forming boundaries of the bottom sides 13 against end portions 122 of the bucket front 12.

Reference is now made to figures 2 and 3.

Each side portion 14 forms a coupling portion 141 provided with several first cut-outs

143 extending from an abutment surface 142 facing the sliding surface 121 of the bucket front 12. In the embodiment shown, said first cut-outs 143 completely pene- trate the abutment surface 142, thereby creating a divided abutment surface 142. The cut-outs 143 are shown with a rectangular cross section and a bevelled mouth portion 1431. From a front face 144 facing away from the bucket side 13, a bolt hole 145 ex- tends into the side portion 14 and through the cut-outs 143, perpendicularly to the longitudinal axes of the cut-outs 143. A bolt-hole extension 148 extends from a bot- tom portion of the bolt hole 145 and ends in an edge face 147 opposite the front face

144 of the side portion.

The end portions 122 of the bucket front 12 are provided with several second cut-outs 123 corresponding with the cut-outs 143 in the coupling portions 141 of the bucket sides 13. Said second cut-outs 123 are provided with countersunk mouth portions 1231 and are arranged to receive coupling pins 15.

The coupling pins 15 are provided with projecting first end portions 151, shown here with conical abutment surfaces 1511, complementary to the mouth portions 1231 of the cut-outs 123 of the bucket front 12. A second end portion 152 of each coupling pin 15 is provided with a transverse bolt hole 153 arranged, when the bucket front 12 is abutting against the abutment surfaces 142 of the side portions 14 and the coupling pins 15 have been inserted through the cut-outs 123 of the bucket front 12 and into the cut-outs 143 of the respective side portion 14, to be in line with the bolt hole 145 through the coupling portion 141 of the respective side portion 14. It is an advantage if the coupling pins 15 have a rectangular cross section so that the bolt holes 153 of the coupling pins 15 are oriented correctly when the coupling pins 15 are inserted into the cut-outs 123 of the bucket front 12.

An elongated attachment bolt 16 is arranged to be inserted into the bolt holes 145 in the coupling portion 141 of the side portion 14.

P28218PC00 description and claims When the bucket front 12 is being attached to the digging bucket 1, the bucket front 12 is brought into position on the abutment surfaces 142 of the coupling portions 141. The coupling pins 15 are inserted through the cut-outs 123 of the bucket front 12 into the cut-outs 143 of the coupling portions 141 so that the bolt holes 153 of the cou- pling pins 15 and the bolt holes 145 of the respective coupling portion 141 are in line. The attachment bolt 16 is then inserted into the coupling portion 141 so that the cou- pling pins 15 are locked to the coupling portion 141 and thereby attach the bucket front 12 to the digging bucket 1.

When detaching the bucket front 12, for example because of wear or damage, the attachment bolt 16 may be released from its position in the coupling portion 141 by a suitable tool (not shown), for example a punch, being inserted into the bolt-hole ex- tension 148 of the coupling portion 141 and the attachment bolt 16 being pushed out, for example by the punch being struck.

It should be noted that all the above-mentioned embodiments illustrate the invention, but do not limit it, and persons skilled in the art may construct many alternative em- bodiments without departing from the scope of the attached claims. In the claims, reference numbers in brackets are not to be regarded as restrictive.

The use of the verb "to comprise" and its different forms does not exclude the pres- ence of elements or steps that are not mentioned in the claims. The indefinite article "a" or "an" before an element does not exclude the presence of several such elements.

The fact that some features are indicated in mutually different dependent claims does not indicate that a combination of these features cannot be used with advantage.

P28218PC00 description and claims