Endless belt power transmission systems or components – Means for adjusting belt tension or for shifting belt,... – Guide roll mounted for movement of its axis along...
Utility Patent
1999-02-12
2001-01-02
Underwood, Donald W. (Department: 3652)
Endless belt power transmission systems or components
Means for adjusting belt tension or for shifting belt,...
Guide roll mounted for movement of its axis along...
C037S397000, C414S693000
Utility Patent
active
06168542
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to mining shovels, and in particular to an improved system for adjusting the length of a crowd rope on a mining shovel.
Mining shovels use a dipper bucket mounted on the end of a handle which is supported on a boom. A crowd system is used to power and position the dipper through its cycle of digging and dumping a load. The crowd system will either push or “crowd” the dipper and handle out away from the supporting boom or will “retract” the dipper and handle back toward the boom.
A steel rope system is often used to accomplish the crowd and retract motion of the shovel handle. The steel rope system is often a continuous loop system. The continuous loop system must be tightened at the time of initial installation as well as after a period of shovel operation since the crowd and retract ropes will be stretched by the large working loads to which they are subjected. Such a rope adjustment is required whenever the rope system has excessive slack. Typically, the rope adjustment may be required about once a week.
One existing take-up system for adjusting the length of the rope is located at the front end of the shovel handle behind the dipper. This current system utilizes a hydraulic jack and steel plate shims for adjusting and locking the ropes. When this rope system needs to be adjusted, the handle is extended until the dipper is set on the ground. Even with the dipper resting on the ground, the rope take-up system can be about 20 feet above the ground in large modern electric mining shovels. Workers need to climb to that height to perform the work and need to move the heavy shims, weighing 30 to 60 pounds each, this awkward elevated position. Also, the current position of the crowed rope take-up mechanism near the dipper means that the heavy weight of the mechanism detracts from the allowable pay load that can be carried in the dipper.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a crowd rope take-up mechanism which is readily accessible to workers for physical adjustment and which is positioned on the handle away from the dipper to increase the allowable pay load in the dipper.
It is a further object of the invention to provide a crowd rope take-up system having simplified means for adjustment.
In accordance with the invention, the crowd rope take-up system is located at the end of the handle remote from the dipper. A loop of the crowd rope extends about a sheave that is mounted on a member that can move parallel to the longitudinal axis of the handle. Means are provided to extend and retract the member relative to the handle to adjust the position of the sheave and thereby adjust the length of the rope. Preferably, the member is a cylinder having external screw threads engaged by a nut wheel. The nut wheel has external gear teeth engaged by a worm gear. The cylinder is held against rotation and the nut wheel is restrained longitudinally so that turning the worm gear advances or retracts the cylinder and its sheave.
The worm gear has a square notch at one end to receive a power wrench. The square notch is also used to receive a retainer plug that locks the worm gear against accidental rotation and thereby locks the crowd rope into an adjusted position.
The exterior of the cylinder and its screw threads can be covered by a bellows extending along the cylinder.
The foregoing and other objects and advantages of the invention will appear in the detailed description which follows. In the description, references are made to the accompanying drawings which illustrate a preferred embodiment of the invention.
REFERENCES:
patent: 106248 (1870-08-01), Bechtel
patent: 1464411 (1923-08-01), Genova
patent: 2472461 (1949-06-01), Blackburn
patent: 3481489 (1969-12-01), Stauffer
patent: 3608755 (1971-09-01), Solokhin et al.
patent: 3843095 (1974-10-01), Rupert
patent: 3933260 (1976-01-01), Kronlokken et al.
patent: 5259821 (1993-11-01), Bryant
patent: 1463269 (1967-03-01), None
patent: 2161244 (1973-07-01), None
patent: 491191 (1938-01-01), None
patent: 1170170 (1969-11-01), None
Bucyrus International, Inc.
Quarles & Brady LLP
Underwood Donald W.
LandOfFree
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