US3112572A - Dragline bucket trunnion - Google Patents

Description

Dec. 3, 1963 P. v. LARSEN DRAGLINE BUCKET TRUNNION 3 Sheets-Sheet 1 Filed Sept. 6, 1962 by V 9/2 L 11 a 2L) P. V- LARSEN DRAGLINE BUCKET TRUNNION Dec. 3, 1963 3 Sheets-Sheet 2 Filed Sept. 6, 1962 5 ,f w g United States Patent Ofi ice 3,llZ,57Z l e-dented Dec. 3, 1953 3,112,572 DRAGLEIIE BUCKET TRUNNlGN Paul Vernon Larsen, Portland, Greg, assignor to Eseo Corporation, Portland, Greg, a corporation of Oregon Filed Sept. 6, 1962, Ser. No. 221,792 6 Claims. ((31. 37l35) This invention relates to a dragline bucket trunnion, and, more particularly, to a trunnion characterized by advantageous positionability for stabilizing the bucket during hoisting.

The dragline bucket trunnions are fittings provided on the vertical side walls of the bucket to which the hoist chains are connected. The trunnion locations are calculated from the center of gravity of the bucket so as to carry the loaded bucket in the air tilted back at about a angle and also to carry the bucket in a vertical position after it has dumped the load, i.e., with the front of the bucket hanging down.

It has been difficult to calculate this exact center both vertically and horizontally for different types, sizes and widths of buckets. Also, the center of gravity changes with the bucket loading. Buckets loaded with clay to the top of the bucket have a different carrying factor than if the clay were piled over the bucket as high as the spreader bar. Still further, the center of gravity location would be different if the bucket were loaded with large rocks having considerable void spaces. Yet further, an entirely different centroidal condition is met for a bucket digging under water, where the angle of repose of the material at the front of the bucket changes. It is diiiicult to hold the material in the bucket when loading under water, and it is not uncommon for gravel to load in a bucket on a straight line from the lip to the top of the back of the bucket, which requires still another trunnion location to balance the bucket properly.

From the foregoing, it is seen that it would be especially desirable to have a positionable trunnion, and, although attempts at this have been made in the past, they have een attended by considerable diiiiculty. It is to be appreciated that the trunnion provides a critical connection subject to considerable strain when the loaded bucket is lifted. Therefore, it has not been found practical to make an easily adjustable or releasable connection. V/ith contemporary trunnions, it takes three men 12 to 15 hours, or one man about three days, toremove the rivets and trunnion, burn or drill new holes, and replace the trunnion in the new position. Not only is this expensive, but, more importantly, it puts the bucket out of service during this time. Also, it is necessary to Weld up all of the old holes from the previous location. Further, because of the variation in material and the new location of the trunnion, it must be assumed that it is possible to still have an incorrect location after the trunnion has been adjusted through the lengthy procedure just outlined.

t is therefore an object of the instant invention to provide a novel trunnion that overcomes the shortcomings of previously-employed trunnions, i.e., being characterized by ready repositionability so as to accommodate the bucket to a variety of loading conditions.

Another object is to provide a trunnion for a dragline bucket characterized by a high degree of stability in use and which is constructed to resist a variety of stresses in addition to those normally encountered in hoisting.

Still another object is to provide a novel trunnionequipped bucket wherein the bucket is adapted for a variety of service conditions.

Other objects and advantages of the invention may be seen in the details of construction and operation set down in this specification.

The invention is described in conjunction with the accompanying drawing, in which:

FIG. 1 is a fragmentary rear elevational view of a dragline bucket equipped with the inventive trunnion;

FIG. 2 is a side elevational view of the bucket seen in FIG. 1;

FIG. 3 is an enlarged fragmentary side elevational view of the portion of the bucket equipped with inventive trunnion;

FIG. 4 is a sectional view, taken along the line 44 of FIG. 3;

FIG. 5 is a reduced size rear the sight line 55 of FIG. 4;

FIG. 6 is a view similar to FIG. 4 but of a modified form of trunnion;

FIG. 7 is a view similar to FIG. 5 but taken along the si ht line 7-7 applied to FIG. 6; and

FIG. 8 is a fragmentary perspective view of the trunnion-equipped bucket.

in the illustration given, and with reference to FIGS. 1 and 2, the environment for the invention is seen to include a dragline bucket generally designated 10 which is made up of side walls 11 and 12, a rear end Wall 13, and a bottom wall 14. This provides an open top and open front for the accumulation of gravel, rock, etc. by virtue of a dragging operation initiated by a pulling force exerted on the drag chain 15. The drag chain 15 is secured by virtue of a hitch extension 16 to a hitch plate 17 on the forward side walls 11 and 12.

Pulling of the bucket by exerting a pulling force on the drag chain 15 advances the bucket with its forward lip and teeth 1i biting into the ground. Dumping of the bucket is achieved through a cable 19 reeved in a hoist socket 2t? and connected to the arch anchor 21.

Hoisting of the bucket is achieved through a cable 22 connected to a hoist socket wedge 23, and this in turn to the hoist chains 24. The hoist chains 24 are maintained in spaced-apart fashion by a spreader bar 25 with the lower end of the chains 24 being connected to a trunnz'on link 26 connected to the trunnion generally desigated 27.

Referring now to FIGS. 3-5, the trunnion 27 is seen in enlarged form and is secured to a trunnion plate 28 provided as a reinrorcement for the side wall 12.

The trunnion is seen to include a unitary body made up of a circular plate-like portion 29 (see FIG. 5). One quadrant as generally designated 34 in FIG. 3 is interrupted to provide a transversely thickened portion generally designated 31 in FIG. 4. The thickened portion 31 is equipped with aligned openings 32 and 33 in which the trunnion pin 34 is received. The trunnion pin 34 is maintained in place by virtue of a keeper 35 extending through the head 34a of the pin and through aligned openings in the enthickened portion 31. The enthickened portion 31 is clevis-like in nature and provides spaced-apart, pin-receiving arms 36 and 37 carrying, respectively, the holes 32 and 33. The space between the arms 36 and 37 receives the trunnion link 26.

The circular plate-like portion 29 is seen to include a plurality of arcuately-disposed holes 38. Similarly-arranged holes 39 (see FIG. 4) are provided in the side wall 12 of the bucket it) for the receipt of securing bolts 49. It will be appreciated that other securing means, such as rivets, may be employed. However, it will be seen that the trunnion pin 34- is positioned eccentrically relative to the center of the bolt holes 38.

The enthickened portion 31 is seen to taper downwardly and inwardly as at 41 (see FIG. 4). and this is advantageous L1 maintaining the bearing of the trunnion against the reinforcing plate 28 so that the trunnion mounting plan view, taken along B :9 will not be knocked off by impact with rocks while the bucket is being dragged.

Reference to FIG. 5 reveals that the bolt openings 33 are disposed about an arc of about 270-ieaving with out openings the quadrant providing the trunnion pin support. However, the bucket side wall has openings over a 360 arc. Also, the bearin face of the trunnion 27 is equipped with a reinforcing web 4-2 extending along a a diameter bisecting the quadrant 30.

On a 35 cubic yard bucket, the holes 38 are provided at 15 intervals, with the center of the pin 34 lying on the continuation of the periphery of circular plate-like portion 29, being on a radius of 11%". This arrangement yields 105 of are as the full adjustment of the trunnion, and the maximum possible adjustment of the bucket provides dumping at 6 /2 from the vertical.

In the operation of the device, the eccentric trunnion pin 34 is positioned according to calculation to develop the proper lifting and dumping action. Normally, this is at 30 to the vertical, as shown in FIG. 3. Should this prove erroneous, the bolts are removed from the various openings 39 and 38 and the trunnion rotated to a new position, after which the bolts are reinstalled.

The size of the trunnion and the arcuate spacing of bolt holes may be varied according to the size of the bucket. The modification seen in FIGS. 6 and 7 is for use with an 85 cubic yard bucket, and in this installation, the openings are arcuately spaced by 18. Other spacings, of the order of 1020, depending upon the size of the bucket, may be advantageously employed. I prefer, however, to limit the openings to the 270 arc shown so as to have maximum metal in the important bearing area under the trunnion pin. In the case of larger buckets requiring larger trunnions, as seen in FIGS. 6 and 7,

the inventive trunnion 127 is equipped wtih a centering pin 143, which extends through an opening 144 provided in the bucket side wall. The integrally cast pin 143 serves as a center to fit into the hole 144 so that the trunnion may be rotated on the center when adjusting and assembling. The pin 143 also acts as a shear pin in assisting the rivets or bolts to hold it tightly to the side of the bucket.

While, in the foregoing specification, a detailed description of an embodiment of the invention has been a set down for the purpose of explanation thereof, many variations in the details herein given may be made by those skilled in the art without departing from the spirit and scope of the invention.

I claim:

1. In a dragline bucket a body having upstanding side walls, and connective rear and bottom walls, a trunnion on each side wall for connecting a hoist chain thereto, each trunnion comprising a unitary body having a plurality of holes extending therethrough,

said holes being arcuately arranged, said body being equipped with a pin-carrying portion eccentrically related to the center of the hole arc, said side walls having a plurality of openings also arcuately arranged to register with said holes, and means extending through said openings and holes for releasably securing said trunnions to said side walls.

2. The structure of claim 1 in which each of said trunnions is equipped with holes over about an arc of 270.

3. The structure of claim 1 in which said holes are spaced apart by an angle of about 10-20".

4. The structure of claim 1 in which said pin-carrying portion tapers inwardly and downwardly.

5. The structure of claim 4 in which said body is equipped with. an integral pin centered relative to said arcuately arranged holes, each of said side walls being apertured centrally relative to said openings, with said pin being iournaled therein.

6. In a dragline bucket, a body having upstanding side walls and connective rear and bottom walls, a trunnion on each side wall for connecting a hoist chain thereto, each trunnion comprising a unitary, generally circular body having one side bearing against the outside of a bucket side wall, the opposite side of said body being tapered toward said one side to provide an enthickened portion oflset relative to the center of said circular body, aligned pin-carrying openings in said enthickened portion for connection to a hoist chain, a plurality of holes arcuately arranged about said center and extending through said body, said side walls having a plurality of openings also arcuately arranged to register with said holes, and means extending through said side wall openings and holes for releasably securing said trunnions to said side walls.

References Gited in the file of this patent UNITED STATES PATENTS Re. 19,683 Pollock Aug. 27, 1935 7 1,050,838 King Jan. 21, 1913 1,104,771 Bjorge July 28, 1914 2,092,556 Page Sept. 7, 1937 2,909,352 Van Buren Oct. 20, 1959

Claims (1)

1. IN A DRAGLINE BUCKET, A BODY HAVING UPSTANDING SIDE WALLS, AND CONNECTIVE REAR AND BOTTOM WALLS, A TRUNNION ON EACH SIDE WALL FOR CONNECTING A HOIST CHAIN THERETO, EACH TRUNNION COMPRISING A UNITARY BODY HAVING A PLURALITY OF HOLES EXTENDING THERETHROUGH, SAID HOLES BEING ARCUATELY ARRANGED, SAID BODY BEING EQUIPPED WITH A PIN-CARRYING PORTION ECCENTRICALLY RELATED TO THE CENTER OF THE HOLE ARC, SAID SIDE WALLS HAVING

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