US2826838A - Four-rope clamshell cleanup type bucket - Google Patents

Description

8 March 18, 1958 E. J, SCHEIB ET AL- 2,828,838

FOUR-ROPE CLAMSHELL CLEANUP TYPE BUCKET Filed April 8, 1954 2 Sheets-Sheet 1 Q 628% vIIVVEIVTOVR. BY W March 18, 1958 Filed April 8, 1954 E. J. SCHEIB ETAL 2,826,838

FOUR-ROPE CLAMSHELL CLEANUP TYPE BUCKET 2 Sheets-Sheet 2 INVENTOR.

United States Patent C) FOUR-ROPE CLAMSHELL CLEANUP TYPE BUCKET Elmer J. Scheib, Aspinwall, and George J. Ehrhardt, Oakmont, Pa., assiguors to Blaw-Knox Company, Pittsburgh, Pa., a corporation of Delaware Application April 8, 1954, Serial N0. 421,896

6 Claims. 01. 37-186) This invention relates to a new and useful improvement in a clamshell bucket and more particularly to an arrangement of sheaves and reeving of the cables in the bucket. cleanup buckets used for unloading boats having nar row hatch openings where a wide spread of the scoops is required to clean up the final portion of the cargo, the main portion of which cargo has been removed by digging buckets. t

Such cleanup buckets are required to secure a very long spread when in the open position and at the same time to have a short closed length so that they may be passed through the narrow hatch openings into the hold of the ship. Cleanup buckets require only sufficient closing power to enable them to scrape together the material between their widely spread jaws or scoops and then close the scoops to contain the material so gathered. Such buckets are operated and manipulated by cables reeved over sheaves within the bucket, and the cables are actuated by drums mounted on a movable carriage that travels on an overhead track or runway.

Such buckets are of the class known as four-rope buckets, indicating that four sections of cable pass from the carriage towards the bucket. Two of these sections are for opening the bucket while the other two are to close the bucket. pass directly into the bucket and around the opening sheave, but each section of closing cable generally has The invention is particularly adapted for use in I cleanup bucket during the opening and closing operations of the bucket so that none of the sheaves have any bodily movement with respect to either the bucket or the cables.

The invention will become more apparent from a consideration of the accompanying drawings constituting a part hereof in which like reference characters designate like parts in the figures.

Figure 1 is the side elevation of the bucket in wide open position. I

Figure 2 is a similar view showing the bucket in closed position. I

Figure 3 is a section taken along the line AA in Figure 2 showing the lefthand scoop of Figure 2.

Figure 4 is a diagrammatic plan view of a carriage used to manipulate the bucket which is suspended by the cables shown.

Figure 5 is a partial sectional end elevation along the lines BB of Figure 2 showing the cable and sheave arrangement in the upper part of the lefthand scoop arm of Figure 2.

In Figure 1 of the drawings the bucket, according to our, invention, is indicated generally at 2 and comprises a pair, of hinged arm frames 4 and 6 having scoops 8 and 10 respectively, secured to the lower ends thereof, the arm frames being pivoted on a head 12.

The head 12 is a simple box-like structure formed by fabricating channels or plates into a generally rectangular structure. As best seen in Figure 3, the top of the head structure is provided with rotatable cable guide rollers 14 and 16 journaled in the head at right angles to each other. The'lower part of the head is provided with parallel hinge shafts 18 which provide pivot axes for the arm frames to be suspended from the head. A bumper 20 is attached to the lowermost part of the head structure so that it will restrict the upward movement of t s an opening-cable sheave block disposed between the arms.

The two sections of opening cable generally above the bucket head, each such set of cable sections being mutuallyconnected to the customary spreaderbeam, two of which are required per bucket and which at all times must be suspended below the carriage but above thebucket, within a substantial vertical zone determined by the range of vertical movement of the spreader-beams. This limits the extreme elevated position of the bucket to a distance considerably below the carriage, above which the bucket may not be raised,.and thus seriously restricts the height which the bucket can clear on the particular bridge with which it is used.

It is among the objects of our invention to reduce the minimum distance between our cleanup bucket and the drum on the over-head carriage and thus to improve the operations of the cleanup bucket with a given hoist structure above the cleanup bucket.

It is a further object to provide cleanup buckets with sheaves arranged so that the closing cables within the buckets will be reeved directly from sheave to sheave and to dead-end connections without any off-leads or fleet The arm frames 4 and 6 are substantially identical and are of fabricated metal plate construction comprising inner webs 22 and outer webs 24 as seen in Figure 3. These webs are connected at the front and back by side plates 26, Figure l. The outer webs 24 are connected together by back plates 28. The arms are provided with meshing gear teeth 7, 7a which interact to coordinate the arm movements. The scoops 8 and 10 are likewise of fabricated metal plate construction and are secured to the lower ends of arm frames 4 and 6 by any suitable means such as rivets or welding (not shown).

Top guide sheave 30 having a pitch circle 32, is mounted in the upper part of each arm frame on hinge shaft 18. The hinge shafts 18 are parallel to one another and are mounted at each end in journals 34 that are fixed in upper ends of inner and outer webs 22 and 24. This construction allows the arm frames to swing on the hinge shaft and still maintain the same relative position to the top guide sheave. The hinge shaft 18 is also fixed in the proper position in the lower part of the head so that the pitch circle 32 will be in alignment with the cable guide rollers 14 and 16.

Each arm frame has a pair of closing sheaves 36 and 37 that are mounted on pins 38 and 40 at the lower ends of the arm frames. Pins 38 and 46 are journaled in fixed position between bearing brackets 42 and 44 and inner webs 22 in such a manner that the diametral planes of closing sheaves 36 are parallel to and spaced on either side of the diametral plane of top guide sheave 3%. The

ametral planes of the closing sheaves are perpendicular" to the parallel axes about which the scoops of the bucket rotate.

Hence any point on an opposite scoop penta trated by the extended dianietral plane of .a closing sheave must always lie in such plane for all positions of the scoops; and the opposite pairs of closing sheaves 36, 36 and 37, 37 therefore always occupy thesam'e di'ametral plane. Intermediate the topcguide sheaves andrclosing sheaves, there are auxiliary guidesheaves as follows. First auxiliary guide sheaves 46 are journa'led between upper support channels 48 and 50 which extend transversely between side plates 26 so that they provide .a fixed support for the sheaves. Ityvill be noted 'by inspection of Figure 1 that these first auxiliary guide sheaves are placed so that their diametral plane is tangent to the pitch circle 32 of top'guide sheave 30. Similarly, second auxiliary guide sheaves 52 are journaled between lower support channels 54 and "56 that likewise extend transversely between the inner webs 22. Second auxiliary guide sheaves 52 are also placed so that, their diametral plane is tangent to the pitchcircle 58 of closing sheaves 36 and 37 respectively in the right and left arm frames of Figure 1. These auxiliary guide sheaves arenecessary to maintain true leads of the cable to the top guide sheave and to a closing sheave.

An opening sheave block 60 is disposed between arm frames 4 and 6 and generally between the diametral planes of the pairs of closing sheaves. The block 60 has a sheave wheel 62 journaled in the center portion of the block. The upper part of the. block is provided with a pad 64 (Figure 3) that will engage bumper 20 in the head, if the block is moved to its extreme. upward position between the arms. The lower part of. the rblock60 has pins 66 fixed therein so as to provide attachment points for toggle links 68.

Toggle links 68 are pivoted at their lower ends to shafts 66 and provided with meshing gear segments 70 r to insure that the toggle links will move in coordination with any vertical movement of block 60. The upper part of toggle links 68 are provided withhubs 72 which are pivoted to pins 74 that are fixed in intermediate locations in the arm frame. Toggle links 68 arealso provided with an open central portion 76. of suflicient size so that a cable may be passed through the opening without interference from the toggle link. Itmay thus be seen that the togglelinks will cause the arm frames to be spread apart or moved together in accordance with the vertical position of opening sheave block 60.

The arm frames themselves, are coordinated by the meshing gear segments 7, 7a of the upper arm frames so that they will move together when toggle links v68 act on pins 74 to change the positionof the arm frames.

An opening cable 80 is passed in a closedlooparound sheave 62 to determine vertical position of block 60 within the arm frames. Leads-of opening cable 80 are guided in a straight linethrough the head 12 by rollers 14.'and 16 in thehead, and pass directly to an overhead carriage 82. Both ends of opening cable 80 are fixed at opposite ends of opening drum 84, as shown in Figure 4. Since the opening drum 84 may be rotated by suitable power means (not shown) in-the carriage 82, the opening cable 80 may be used to vary the vertical positionof sheave block 60 and thereby to establish the position of the bucket which is attached thereto.

A closing cable 86 is dead-ended at a point88'fixed by a bracket 90 in the left-hand scoop as seen in Fig. 1. The point 88 is in the diametral plane of the pair'of sheaves 36, 36; and the closing cable 86 lies in this plane as'it extends across the bucket lengthwise about the righthand sheave 36 as seen in Fig. l, and thence back across the bucket lengthwise to the left-hand sheave 36, and upwards in the same diametral plane to its point of tangency with the guide sheave 52. At this point the cableis translated to a plane at right angles to the diame'tral plane of the sheaves 36, in which it remains as it passes up-' wards around the sheaves 52 and 46. The cable 86 leaves the sheave 46 at its point of tangency with the diamctral planeof theupper guide sheave 30, and in that .plane finally passes around sheave 30 and out of the a cable end maybe secured at a. point 92 in the bracket 94 at the lower part of the righthand arm frame in such a manner that the cable need pass around only one closing she-ave in its operations. In any case, the points 88or 92 are in the diametral planes of the closing sheaves.

In a similar manner, closing cable, 96 may be dead ended at the rear of righthand arm frame at point 98 in bracket 100 in the common diametral planes of the pair of opposite sheaves 37, 37; and passed across the bucket around the lefthand closing sheave 37 to the righthand closing sheave 37 and then upward around the auxiliary sheaves and top guide sheaves and cable guide rollers to drum 90 in the same manner as closing cable 86.

Closing cable 96 may alternatively be dead ended at point102 in the bracket 104 at lefthand bucket arm, if it is desired to use only one closing sheave for this closing cable. Such point 102, of course, is understood to be in the diametral plane of sheaves 37.

'The opening and closing of the bucket arms may thus be controlled by rotating closing drum 90 on carriage 82 by suitable power means (not shown) so that cables 86 and 96 may be payed out or drawn in. As can be seen in Figure 4, closing cables 86 and 96 each have their upper end fixed in closing drum 90.

The lateral position of the bucket may be determined by moving carriage 82 on rollers 106 along track 108. Track 108 is mounted on a suitable crane structure moved above the ships to be unloaded.

As seen in Figures 1 and 4, the opening cables and the closing cables 86 and 96 are all maintained in the common plane in alignment with drums 84 and on the carriage; no spreader bars being employed for aligning the cables between the carriage drums and the sheaves of the bucket. By placing all the cables in the central plane, the bucket when suspended by the cables will, in all positions, therefore be balanced on either side of the cables (see Figure 3).

Having described the structure of a preferred embodiment of the invention, it now remains to explain the operation thereof. Figure 1 illustrates the parts in the positions they occupy at the start of the loading operation, the exposed edges of the scoops resting on a layer of material to be handled in that itmay be lying, for example, in the bottom of a ships hold. With the parts in this position, theopening cable 80 is slightly slacked and the closing operation is effected by taking in closing cables 86 and 96 by rotation of closing drum 90 in the overhead carriage82- It will be apparent from a consideration of Figure 1 that intaking inthe closing cables 86 and 96, there will be exerted a strong force tending to close the bucketscoops 8 and 10. As the scoops 8 and 10 are drawn together, the opening sheave block 60 is forced downwardly between the arm frames by movement of both of the toggle links 68,-and the opening cable 80 musttherefore be slackedsufiiciently as above stated, to permit this. Otherwise, the bucket may be bodily lifted .beforelit has been fully closed'and may thus pick up, oulypart of the load or none at all.

With sufiicient slack in the opening cable 80, the exposed edgesof scoops 8 and 10 scrape across the surface 'ofthe :floor deck on which the material to be cleaned up remains. When the scoops are finally brought to gether as shown in Figure 2, they will have gathered a load of material and the bucket is now ready to be hoisted and dumped. The bucket is readily ho'isted' by taking in both the ,opening and closing cables by simul tane'dusly rotating drums 84 and 90in the'overhead carriage- 82. This distributes the load among the several assasss cables and the parts of the bucket remain balanced about the common central plane of the cables. The bucket will remain in the position shown in Figure 2 until it is desired to dump the load. When the bucket has been moved to the desired point by moving carriage 82 on track 108 and, if need be, moving the supporting crane on which the tracks rest to a desired position, it may be dumped by paying out the closing cables 86 and 96 while securing the opening cable 80, or simultaneously taking up the opening cable 80. Considering Figure 2, it will be apparent that if the entire weight of the bucket and load are carried on the opening cable 80, as will be the case when the closing cable is payed out, this whole weight will be effective to cause all the parts of the bucket to descend relative to the sheave block 60 which is held fixed in space between the arm frames. As the remaining portions of the bucket descend, the bucket is opened by the pivoting of toggle links 68 about pins 66 due to the combined weight of the load and the arm frames. The downward movement of the bucket as a whole relative to block 60 is limited by the engagement of pad 64 on the upper part of the block with bumper 20 in the head of the bucket.

The arrangement of the closing sheaves, top guide sheaves and the auxiliary guide sheaves and the reeving of the closing cable herein disclosed, permits the closing cable to be maintained in the diametral plane of each sheave as it enters and leaves each sheave. Thus, the center hne of the closing cable will always be maintained in the diametral plane of whatever sheave it is approaching, since all of the aforementioned sheaves are in fixed journals to prevent any undesirable off leads. The disclosed arrangement of these sheaves and reeving of the cables will, at the same time, avoid interference with the moving parts such as the sheave block 60 and the toggle links 68. The entire construction is further simplified in that no intermediate tackle need be placed between the head of the bucket and the overhead carriage, since only four cables are necessary, if they are spaced and placed in the manner disclosed, to both balance and operate the bucket.

Although we have illustrated and described the preferred embodiment of the invention, it will be apparent that changes may be made in the invention by modifying the construction and arrangement of the parts.

We claim as follows:

1. In a clamshell bucket of the Wide-opening type comprising a pair of arm frames hinged at individual parallel pivot axes in the upper ends of the arm frame to an upper head structure, cooperating opposed scoops at the lower extremities of said arm frames and cable operating mechanisms for spreading said scoops apart and drawing them together, said operating mechanism for drawing said scoops together having in each of said arm frames a top guide sheave rotatable about the pivot axis of the arm frame, a closing sheave journaled in a plane perpendicular to said pivot axes at the lower end of the arm frame at a point close to the scoop, a first auxiliary guide sheave journaled in the upper end of the arm frame at right angles to said top guide sheave, a second auxiliary guide sheave journaled in the lower end of said arm frame at right angles to said closing sheave, a separate closing cable passing through said head structure to the top of each arm frame to be reeved around the top guide sheave and maintained in a common plane by said first and second auxiliary guide sheaves while passing between said top guide sheave and the closing sheave, then reeved around said closing sheave, and passed in a straight line across to the opposite arm frame to be subsequently attached at a dead end in the bucket.

2. In a clamshell bucket of the wide-opening type comprising a pair of arm frames hinged at individual parallel pivot axes in the upper ends of the arm frame to an upper head structure, cooperating opposed scoops at the lower extremities of said arm frames and cable operating mechanism for spreading said scoops apart and drawing them 6 together, said operating, mechanismfor drawing said scoops together having in each of said arm frames a top guide sheave rotatable about the pivot axis of the arm frame, a closing sheave journaled in a plane perpendicular to said pivot axes at the lower end of the arm frame at a guide sheave and the closing sheave, then reeved around said closing sheave, and passed in a straight line across to the opposite arm frame and attached to the lower part of the opposite arm frame at a point in the plane of the said closing sheave.

3. In a clamshell bucket of the wide-opening type comprising a pair of arm frames hinged at individual parallel pivot axes in the upper ends of the arm frame to an upper head structure, cooperating opposed scoops at the lower extremities of said arm frames and cable operating mechanism for spreading said scoops apart and drawing them together, said operating mechanism for drawing said scoops together having in each of said arm frames a top guide sheave rotatable about said pivot axis of the arm frame in a plane parallel with the plane in which said frames swing, a closing sheave journaled in the arm frame at the lower end of the arm frame at a point close to the scoop, in a plane parallel to but laterally offset from the plane of said top guide sheave, a first auxiliary guide sheave journaled in the upper end of the arm frame in a plane at right angles to the plane of said top guide sheave, a second auxiliary guide sheave journaled in the lower end of said arm frame in a plane at right angles to the plane of said closing sheave, and a closing cable passing through said head structure to the top of one of said arm frames being partially reeved around said top guide and closing sheaves, said cable being guided in a straight line between said top guide sheave and said closing sheave by the first and second auxiliary guide sheaves, and then passing to the lower part of the opposed arm frame and fastened to the bucket.

4. A clamshell bucket comprising a head, a pair of hinged arm frames hinged at their upper ends on parallel shafts at the same level in said head, cooperating scoops at the lower end of each of said arm frames, a top guide sheave mounted within each of said frames on said parallel shafts, a pair of closing sheaves journaled in the lower portion of each of said arm frames in a plane parallel to the plane of the top guide sheave, an auxiliary guide sheave journaled in the upper portion of said arm frames in a plane at right angles to plane of said top guide sheave, a second guide sheave journaled in the lower portions of said arm frames in a plane at right angles to one of the closing sheaves, a pair of closing cables passing through the top of said head and having a bight around both pairs of sheaves and guided in the diametral planes of said top guide sheave and said closing sheaves by the auxiliary sheaves as it approaches these respectivesheaves.

5. In a clamshell bucket of the wide-opening type having a pair of arm frames hinged at individual pivot shafts in the upper ends of the arm frame with cooperating opposed scoops at the lower extremities of the arm frames that are coordinated by meshing toggle links having an open frame center portion pivoted to a sheave block disposed between the arm frames, an opening sheave in said block, a top guide sheave mounted for rotation on said pivot shaft, a pair of closing sheaves in the lower part of said arm frame, the said closing sheaves being in a plane laterally beyond the sides of said opening sheave, a closing cable retaining its relative position to said top guide and closing sheaves in all positions of said bucket 7 so 'fth'a tlthe center line of-the cable advances towar'ds said to'pfguide sheave and the closing shavein the diamtral planeof said top ,guide "sheave and said closing sheave by means of apair of spaced auxiliary guide sheaves mounted between support channels that-extend transversely of the arm frames and which are jonrnaled-with their diametral planes tangent to the top guide sheave and the closing sheaves. I

6. In a clamshell bucket of the wide-opening type comprisinga pair of arm frames hingedat individual pivot pointsin the upper ends of the arm frame to an upper head'structure, cooperating opposed scoops at the lower extremities of said arm frames and cable .operating'mecn anisrn for spreading said scoops'apart and drawing them together, said operating mechanism for drawing said 1 scoops together having a top guide sheave in each of 'said arm frames rotatable about said pivot point of the arm frame, a closing sheave journaled in a plane par'allel to the plane of said top guide sheave at the lower end of the arm frame at a point closeto the scoop, anda separate closing cable passing through said head structure to the top of each one of said arm frames to be partially reevcd around said top guide and, closing sheaves so that the closing cableis retained in such a position during the movements of said bucket that the center line of the closing cable always advances in the respective diametral planes of the top guide sheave and closing sheave by means of a'pair of spaced auxiliary sheaves mounted between support channels that extend transversely of the arm frames and which are journaled with their diametral planes tangent to the first guide sheave and said closing sheave.

References Cited in the file of this patent UNITED STATES PATENTS 768,1T8 Ferguson Aug. 23, 1904 1,099,278 Bond June 9, 1914 1,171,393 Morris Feb. 8, 1916 1,422,601 Moore July 11, 1922 1,671,444 Norris May 29, 1928 2,284,390 Harrington May 26, 1942 FOREIGN PATENTS 369,637 Great Britain Marr23, 1930

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