US2727318A - Tooth for digger bucket - Google Patents

Description

Dec. 2U, 1955 Q E EVANS EVAL 2,727,318

TOOTH FOR BIGGER BUCKET 1 i Z4 a if l I 2 5 11 1;) mi 1 f 1w Mrt :.1

fr/577i 572-5# baz/@e555 F2/@22,5 ./izffg/A. Baza@ er Dec. 20, 1955 c. E. EVANS TAL TOGTH FOR BIGGER BUCKET 2 Sheets-Sheet 2 Filed Feb. 19, 1951 65E Haz/0f We L 575 United States Patent 'Office 2,727,318 Patented Dec. 20, 1955 Toorn Fok BIGGER BUCKET Charles E. Evans, Naperville, and Harry A. Barber, Aurora, Ill., assignors to Barber-Greene Company, Aurora, lll., a corporation of Illinois Application February 19, 1951, Serial No. 211,648 Claims. (Cl. 37-142) This invention relates to toothed diggers and more particularly to a tooth for detachable insertion in an edge portion of a bucket.

In the past it has been common practice in the art to provide the edge of a bucket with a plurality of sockets in which bucket teeth can be detachably secured as by means of fastening bolts or pins or the like. It has been conventional to space the tooth sockets along the edge of the bucket as well as to provide a diagonal socket on either or both corners of the bucket. Usually if the bucket has a diagonally located tooth at only one corner, the next succeeding bucket in the series of digger buckets will have the tooth in the opposite corner so that these corner teeth alternate in the series of buckets.

In the use of such digger buckets, it has been found that the usual square end cutter teeth chip or wear olf at the corners. This is especially true of the diagonally located corner teeth which rapidly wear back, decreasing the cutting width of the bucket to a point that the ditch width is not enough to provide proper clearance for the bucket line and supporting boom.

Also, the square end cutter teeth cut a series of rectangular grooves in the face of the ditch which causes the sides' as well as the front of the teeth to cut the material, which action adds to the power requirements.

In addition, due to strength requirements, the body of the tooth is so thick that as the edge wears back an additional thickness of metal is presented for cutting which requires more pressure and more power for digging and also slows up the digging action.

lt is an object, therefore, of this invention to provide an improved digger tooth having a convexly curved cutting edge on the end of a relatively thin concave-convex blade section which due to its form is relatively strong and as the edge wears back presents substantially the same thickness of metal at the cutting end of the tooth, the cutting action being done by the forward convex curved edge and not by the sides. In reality the curved cutting edges of the teeth, when they are spaced alternately on the forward edge of the successive brackets, remove the material or soil in the form of scallops, thereby enabling the soil to be cut freely and with less power especially in the case of a clay type soil. In gravel soil such curved teeth in cutting approach a pick action.

Another object of this invention is to provide a digger tooth which has at each of its ends a convexly curved cutting edge so that the tooth may be reversed in position in its socket when one edge is worn or damaged.

Another object of this invention is to provide in a digger bucket structure an improved digger tooth which in conjunction with its mating socket will be self-locating and to a certain extent self-clamping, under digg-ing action, but will not jam so as to be hard to remove, and also, to provide means to keep it from falling out under other conditions.

We have found if a digger tooth is this feature lto be advantageous since provided with a bolt of sufficient size tooth socket portions '14, each of which to hold it in place, considerable diculty is encountered when changing teeth due to jamming or eezing to the nut, etc. On the other hand, if tapered fits, of such proportions as to be self-retaining were used, as in our invention, the freezing disadvantage of bolted teeth is eliminated. We propose to use a wedge arrangement such as to overcome previous objections and make practical forging and casting practices. The wedging angle We use, is such that the projection length of the tooth beyond the socket is held to a reasonable tolerance in spite of a relatively loose iit of the tooth in the socket.

We therefore provide for use in a bucket tooth socket of curved cross-section, a digger tooth comprising a 1ongitudinally channeled element terminating in a blade of concave-convex curved cross-section with a convexly curved cutting edge at its outermost extremity; the blade being of substantially uniform cross-section so that the cutting edge as it wears back, is not substantially thickened.

Another feature of the invention relates to providing the channeled tooth element with identical blade sections at its opposite extremities which are selectively usable by reversal of position of the element in the bucket socket.

Yet another feature of the invention relates to providing an intermediate portion of the channeled tooth element with a thickened boss inside of the channel and having a sloping surface for wedging contact with a portion of the bucket inside of the bucket tooth socket, whereby the tooth will be self-positioning and self-clamping in the socket.

Another and further feature of the invention relates to providing the wedging boss of the channeled tooth with a hole loosely receiving a pin-like member which serves to prevent the tooth element from dropping out of its socket upon any disengagement of the wedged contact between the tooth and the wall of the socket.

Another feature of our tooth is that the sloping surface nearest the cutting edge, in conjunction with the leading edge of the bucket above the same, forms a stripper that promotes a scouring action and tends' to deflect the material upward so that it is less liable to become packed in the bucket.

Other objects and features of this invention will more fully appear from the following detailed description taken in connection with the accompanying drawings which illustrate a single embodiment thereof and in which:

Figure 1 is a plan view of a bucket having spaced curved sockets with channeled digging teeth which embody the features of the invention;

Figure 2 is a cross-sectional View taken on substantially the line II-Il of Figure 1, looking in the direction of the arrows;

Figure 3 is an enlarged plan view of one of the digger teeth;

Figure 4 is a longitudinal cross-sectional View taken lon substantially the line IV-IV of Figure 3, looking in the direction indicated by the arrows;

Figure 5 is an end view of the tooth shown in Figlure 3; and

Figure 6 is a fragmentary end view of one of the sockets in the bucket edge and showing the socket with the tooth removed.

As shown on the drawings:

The reference character 10 (Figs. l and 2) designates generally a digger bucket which may be of any suitable construction as long as its forward edge is provided with sockets of such type that they will accommodate the digger teeth of our invention. This bucket, as shown, includes a bottom 11 and opposite sides 12-12; the bottom terminating in a forward edge portion 13 having spaced is adapted to receive a digger tooth 15 embodying this invention.

In Figures 2 and 6, we have shown the construction of the socket portions 14 which are substantially identical in construction; and hence a description of one will suftice for all. Y

Each socket portion 14 includes an elongated socket hole 16 of concave-convex cross-sectional shape corresponding with the cross-sectional contour of the tooth so that a tooth may be inserted endwise into such socket hole.

Also each socket portion has a projection 17 extending into the socket hole 16 and which terminates on its forward or outer side in a sloping or inclined surface 18 for wedging cooperation with the teeth 15 (Fig. 2).

Since all of the digger teeth 15 are identical and interchangeable, a description of one will suce for all. The digger tooth 15 of our invention is best shown in Figures 3, 4 and 5. It will be noted that this digger tooth comprises an elongated channeled element of concave-convex curved cross-section. The ends of this element are formed into opposite blade sections 20-20 which are identical and each of which terminates on its outermost extremity in a convexly curved cutting edge 21.

The two blade sections 20 have between them an enlargement or boss 22 projecting into the channel of the tooth. This boss 22 is provided with a transverse hole 23 substantially midway between the cutting edges 21-21. Also the boss 22 is connected at opposite sides to the blade sections 20-20 by sloping out wedge surfaces 24-24.

As noted before the channeled tooth is of generally the same cross-sectional contour as that of the bucket socket hole 16 so vthat either of its ends may be inserted endwise into the socket portion.

Now due to the fact that the projection 17 of the socket portion is in the path of a tooth inserted in the socket its slanting surface 18 will come into wedging contact with one of the wedge surfaces 24 on the tooth, depending on which end of the tooth is inserted in a socket. Once the tooth is inserted in the socket a slight pressure of its exposed cutting edge 21 will result in the tooth being frictionally clamped or wedged against the sloping surface 18 of the socket projection 17. This enables the tooth to be self-clamping and positioning in the socket during the digging action. In other words the sloping surfaces provide for tight frictional load bearing contact between the tooth and the bucket.

However, in order to prevent any possibility of the tooth becoming accidentally displaced or dropping out of the bucket when the bucket is upside down, a cotter pin 25 is used. From Figure 2, it will be apparent that the pin extends through the hole 23 in the tooth, which hole is considerably larger than the shank of the pin although the pin is tightly clamped to the cooperating socket portion 14.

Now'by reason of the fact that the boss 22 of the tooth is loosely fitted around the shank of the cotter pin 25,'it follows that the pin is not subjected to any pressure during the digging operation. As a matter of fact any pressure against the exposed cutting edge 21 of the tooth is translated into increased wedging pressure between the tooth and the bucket socket portion.

It is further clear that upon the cutting edge becoming badly worn or damaged the tooth may be easily removed by first removing the pin and then lightly tapping on the innermost end of the tooth to disengage the wedge contact between the surfaces 18 and 24. Thereafter, since the ends of the tooth are identical, the tooth may be reversed in position so as to expose the other cutting edge for digging action.

A very important feature of the invention relates to the convex curving of cutting edge 21 so that its medial portion is forwardmost and whereby there are no corners presented at the ends of the cutting edge such as would be present in a straight edge. This convex curving of the edge provides' clearance at the ends of the edge for material or soil to ow freely as the same is cut and with less power. When a series of these teeth are used in spaced relationship, they will remove or cut the soil in the form of scallops which is especially advantageous in digging clay soil. In a gravel type of soil our novel curved tooth will approach in action a pick action.

In addition, when one of our curved teeth is set at an angle in the corner socket of the bucket, we find it cuts more freely than a square or straight edge tooth and does not have any corners to wear off. Therefore, it maintains ditch width and proper clearance much longer.

From Figure 4 it will be clear that each socket portion or section 20 is of substantially uniform cross-sectional thickness so that relatively little or substantially no thickness occurs at the cutting edge as it wears in continued digging. This is very important as these teeth of our invention have been found to require less pressure to be forced into the face of the cut, use less power when digging and also enable faster ditching action.

In the foregoing description it has been assumed that the concave side of the tooth is located uppermost, however, in some cases it might be advantageous to form the bucket socket with its concave side lowermost so that the tooth can be used with its convex side uppermost in order to get a so-called rooting action.

While we have found that a double ended tooth is especially desirous from the standpoint of economy in manufacture, strength in construction and double duty in usage, it may be desirable in some instances to use only a single ended tooth.

The shape of the tooth in combination with the tooth support or socket, strips material from the tooth and thus minimizes packing in the bucket. This feature is evident from Fig. 2 wherein it will be observed that the socket or tooth retaining wall portion 14 is below the top surface of the bucket bottom 11 and wherein the channel in each tooth 15 is arranged to guide the material upwardly over the forward edge 13 of the bucket.

We claim as our invention:

l. ln combination in a digger bucket structure, a bucket having a bottom terminating in anV edge provided with a multiple of spaced digger tooth sockets and a digger tooth mounted in each socket and each comprising a longitudinally channeled member of generally concaveconvex cross section having opposite ends formed with rounded cutting edges, said member having extending transversely into its channel a thickened intermediate mounting boss tapering at opposite sides toward said edges to define wedge mounting surfaces each of which is spaced from the adjoining cutting edge by a section of said member of relatively thin cross section leading into the cutting edge, said channeled member dening a trough for conducting dug material toward and above said boss, each of said tooth sockets having a concavely formed tooth supporting wall for telescopingly receiving lengthwise said channeled tooth and aninternal inclined wall complementary to a tapered side of said tooth boss and against which said boss is wedged when the tooth is inserted in the concavely formed wall of the Socket.

2. In a digger bucket structure, a bucket having a bottom terminating in a forward edge provided with a plurality of spaced tooth receiving sockets each-having a tooth supporting wall extending inwardly of said forward bucket edge below the plane of the bucket bottom, a digger tooth for each socket and each having one end detachably telescoping a socket and supported on said wall, the other and outer end of each tooth being formed into a longitudinally channeled concave-convex relatively thin blade terminating lin an outwardly and uniformly convexly curved transverse cutting edge, said tooth channel comprising a trough for conducting dug material cut by said edge rearwardly up over said forward bucket edge onto the surface of the bucket bottom, each of said u sockets having interiorly thereof a wedge surface Aengageable with the inserted end of the tooth to press the tooth wedgingly against said supporting wall of the socket.

3. A bucket digger tooth comprising a longitudinally channeled member of generally concave-convex cross section having opposite end portions formed with transverse rounded cutting edges, said member having extending therefrom an intermediate boss projecting into said channel substantially midway of said cutting edges and tapering at opposite sides toward said cutting edges to define wedge mounting surfaces, each of which is spaced from the adjoining cutting edge by a section of said member of relatively thin cross section leading into the cutting edge, said channeled member defining a trough for conducting dug material from one cutting edge toward and above said boss.

4. In a digger bucket having a bottom with a leading forward edge portion, an enlargement on said forward edge portion having a channeled tooth receiving socket adapted to detachably support a digger tooth, said socket being dei-ined by generally concentric top and bottom walls of concave-convex curved cross section, one of said walls having a projection extending therefrom within said socket from a point spaced a substantial distance inwardly of the entering end of the socket thereof and having a sloping wedging surface engageable with a digger tooth when inserted in the socket.

5. In a digger bucket structure including a bottom havirig a forward digger tooth supporting edge, said edge having a series of spaced enlargements each of which has a tooth receiving socket dened by top and bottom generally concentric spaced curved walls and one of said walls having in said socket a projection extending toward the other wall inside the space separating the Walls and provided interiorly of the socket with an inclined tooth wedging surface.

6. ln a digger bucket structure including a bottom having a forward digger tooth supporting edge, said edge having a series of spaced enlargements each of which has a tooth receiving socket dened by top and bottom generally concentric spaced curved walls and one of said Walls having in said socket a boss extending toward the other wall inside the space separating the Walls and provided with an inclined tooth wedging surface, said concentric Walls having transversely alined fastening element receiving holes intersecting said socket.

7. The digger bucket structure of claim 4 further characterized by a digger tooth of channeled cross section in each socket and having a thickened portion wedgingly engaged by the socket sloping wedging surface.

8. The digger bucket structure of claim 5 further characterized by a longitudinally channeled tooth in each socket and wedgingly engaged by said socket inclined tooth surface.

9. The digger bucket structure of claim 6 further characterized by a tooth detachably mounted in each socket and provided with a fastening element extending into the alined holes in the socket walls.

l0. For use in a digger bucket socket tooth comprising a rigid unitary member having a generally concaveconvex longitudinally channeled section terminating in an outer cutting edge curved convexly outwardly in the direction of the length of the tooth, said member having extending in its channel and generally perpendicular thereto a thickened portion for disposition in the bucket socket, said channeled section between its cutting edge and said thickened portion being longitudinally tapered upwardly in the channel toward said portion and defining a trough with an inclined bottom for conducting material from the cutting edge over said thickened portion.

References Cited in the tile of this patent UNITED STATES PATENTS Re. 8,245 Luse May 21, 1878 265,288 Stonesifer Oct. 3, 1882 841,530 Johnson Jan. 15, 1907 1,258,109 Goeldner Mar. 5, 1918 1,461,136 Moore July 10, 1923 1,522,860 Boots Ian. 13, 1925 1,887,409 Hansen Nov. 8, 1932 2,092,311 Hosmer et al Sept. 7, 1937 2,167,425 Page July 25, 1939 2,220,819 Johnson Nov. 5, 1940 2,251,169 Seal July 29, 1941 2,308,162 Frank Jan. 12, 1943 2,353,685 Askue July 18, 1944 FOREIGN PATENTS 2,949 Great Britain 1892 448,676 Great Britain June 12, 1936 OTHER REFERENCES Dixon: Art Metals Crafts Tools and Supplies, William Dixon Inc., 32-34-36 E. Kinney St., Newark, N. J. Cop right 1933. Received in Patent Oihce August 18, 1936.

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