Claims
- 1. A bucket for loading and unloading cargo comprising:
- a first bucket half and a second bucket half, each bucket half having a top, a closed bottom, a front wall and a back wall which are spaced apart from each other, a closed outside wall and an open inside end,
- means for pivotally securing the tops of said bucket halves together so that said bucket halves are movable between an open position and a closed position pivoting about said means, wherein in said closed position said open ends register with each other to contain cargo within an interior of the bucket and wherein in said open position said open ends of said bucket halves are spaced apart to encompass the cargo to be loaded,
- a head,
- a first pair of cables, said first pair of cables being secured at one end to said head and being secured at their other ends adjacent the outside wall of one bucket half,
- a second pair of cables, said second pair of cables being secured at one end to said head and being secured at their other ends adjacent the outside wall of the other bucket half, and
- means for pivotally moving said bucket halves from said open to said closed position comprising a closure cable extending through said head and through a guide pulley assembly swivelably mounted to at least one bucket half about a vertical axis, said closure cable then being connected within and to each of said bucket halves below said means pivotally securing the tops of said bucket halves together,
- wherein said closure cable returns through said head.
- 2. The invention as defined in claim 1 and comprising two guide pulley assemblies, one guide pulley assembly being mounted to each bucket half, and each guide pulley assembly having two guide pulleys with said closure cable extending between said guide pulleys.
- 3. The invention as defined in claim 1 wherein each bucket half is of a welded steel construction.
- 4. The invention as defined in claim 1 wherein said pivotal securing means comprises a cylindrical tube extending through registering openings on said bucket halves.
- 5. The invention as defined in claim 1 wherein said guide pulley assembly comprises two guide pulleys and a housing, said housing having a central tubular cylindrical portion mounted in a tubular cylindrical journal on one bucket half.
- 6. The invention as defined in claim 5 wherein said guide pulleys are adjacent each other, centered above said tubular housing portion with said closure cable extending between said pulleys and through said tubular housing portion.
- 7. The invention as defined in claim 1 wherein the connection within and to each of said bucket halves is a pulley around which said closure cable passes for pivotally moving said bucket halves from said open to said closed position.
- 8. A bucket for loading and unloading cargo comprising:
- a first bucket half and a second bucket half, each bucket half having a top, a closed bottom, a front wall and a back wall which are spaced apart from each other, a closed outside wall and an open inside end,
- means for pivotally securing the tops of said bucket halves together so that said bucket halves are movable between an open position and a closed position pivoting about said means, wherein in said closed position said open ends register with each other to contain cargo within an interior of the bucket and wherein in said open position said open ends of said bucket halves are spaced apart to encompass the cargo to be loaded,
- a head,
- a first pair of cables, said first pair of cables being secured at one end to said head and being secured at their other ends adjacent the outside wall of one bucket half,
- a second pair of cables, said second pair of cables being secured at one end to said head and being secured at their other ends adjacent the outside wall of the other bucket half, and
- means for pivotally moving said bucket halves from said open to said closed position comprising a closure cable extending through said head and through a guide pulley assembly swivelably mounted to at least one bucket half about a vertical axis, said closure cable then being connected within and to each of said bucket halves below said means pivotally securing the tops of said bucket halves together,
- wherein the connection within and to each of said bucket halves is a pulley around which said closure cable passes for pivotally moving said bucket halves from said open to said closed position, and
- wherein said means for pivotally moving said bucket halves from said open to said closed position includes first and second guide pulleys assemblies and first, second and third closure pulleys, said first guide pulley assembly and said first and third closure pulleys being attached to one of said bucket halves and said second guide pulley assembly and said second closure pulley being attached to said other bucket half, and said closure cable passes through said head, through said first guide pulley assembly, around said first closure pulley, around said second closure pulley, around said third closure pulley, through said second guide pulley assembly and through said head.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. Ser. No. 341,488, filed on Apr. 20, 1989 now abandoned, and entitled POWER BUCKET. .spsb.
I. Field of the Invention
The present invention relates to power shovels for loading and unloading cargo.
II. Description of the Prior Art
The previously known clam shell buckets of the type used with power shovels typically comprise a pair of bucket halves which are pivotally secured adjacent their upper end. The upper end of the bucket is also known as the bucket "head" and this head is connected by a cable to a power mechanism which raises and lowers the bucket. Additionally, a closure cable extends through the head and is secured to the bucket halves for moving the bucket halves between their open and closed positions.
A primary disadvantage of these previously known buckets is that the buckets are made of a cast construction. The cast construction is not only expensive to manufacture but also significantly increases the overall weight of the bucket. This, in turn, reduces the overall cargo capacity of the bucket since the capacity of the power shovel is determined not only by the weight of the cargo within the bucket, but also the weight of the bucket itself. For example, if the power winch for raising the bucket is capable of lifting 15 tons and the bucket itself weighs 5 tons, then only 10 tons of cargo can be lifted by the power shovel.
One reason for the excessive weight of these previously known scoops or buckets for power shovels is that the head is cast as a one-piece construction with at least one of the bucket halves so that the extra metal between the head and the bucket half significantly increases the overall weight of the bucket. Additionally, a cast construction is typically relatively thick which also increases the overall weight of the bucket.
A still further disadvantage of these previously known buckets for power shovels is that the volume carrying capability of the shovel remains fixed even though the density or weight per volume of the cargo varies. Consequently, for particularly dense cargo, overloading of the power winch mechanism can occur when the bucket becomes fully loaded.
A still further disadvantage of these previously known clam shell buckets for power shovels is that, due to the weight of the head, the bucket is top heavy when placed in an at rest position on the ground. This in turn can result in capsizing of the clam shell bucket.
A still further disadvantage of these previously known buckets is that the bucket galls the closure cable during closure and lifting of the bucket. This is especially true when the bucket twists about a vertical axis.
The present invention provides a bucket for a power shovel which overcomes all the above mentioned disadvantages of the previously known devices.
In brief, the bucket of the present invention comprises a first bucket half and a second bucket half wherein each bucket half has a top, a closed bottom, spaced apart front and back walls, a closed outside wall and an open inside. The bucket halves are preferably secured at their tops so that the bucket halves are movable between an open and a closed position. In their open position, the open inside of the bucket halves engage the cargo while, in their closed position, the open insides of the bucket halves register with each other so that the cargo is contained within the bucket.
Unlike the previously known buckets for power shovels, however, the head for the bucket of the present invention is not secured directly to one of the bucket halves. Instead, the head of the present invention is disposed above the bucket halves and is secured to the bucket halves by four cables. Two cables extend to the outside corners of one bucket half and, similarly, the other two cables extend to the outside corners of the other bucket half. The cables, which are much lighter than an integral metal construction, effectively decrease the overall weight of the bucket for a given cargo carrying capability.
A closure cable also extends through the head and is secured to both bucket halves. The closure cable, when retracted, causes the bucket halves to move from their open and to their closed position. Conversely, the normal weight of the bucket halves urges the bucket from its closed and towards its open position. Unlike the previously known buckets, the closure cable extends through a first and second swivelable guide pulley assemblies as it enters and exits the bucket, respectively. The guide pulley assemblies protect the bucket from galling from the closure cable despite twisting movement of the bucket.
Moreover, unlike the previously known buckets, the present invention comprises a welded steel construction. Such a construction is much less expensive not only in fabrication costs but is also lighter in overall weight.
US Referenced Citations (3)
Foreign Referenced Citations (1)
| Number |
Date |
Country |
| 1435528 |
Nov 1988 |
SUX |
Continuation in Parts (1)
|
Number |
Date |
Country |
| Parent |
341488 |
Apr 1989 |
|
Patent Grant
4998762
