US 2249117 A
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July 15, 1941. R. CRANDALL CABLE SPOOLING DEVICE Filed Dec. 23, I939 INVENTOR. R.L.Crandall 19yi ATTORNEYS.
lllllllllllllllllllllllllllllllllllllllllll Patented July 15, 1941 Roberthflrandall,Yuba'City, CaIifJ Y i "Appliance December 23, 1939;,jseeawtzlzimgi.ji ioiai (cram-n90) 1 This invention relates to a cable spooling de vice, and particularly to one especially designed for use in a well drilling rig of the type having a relatively short boom or walking beam and a wide cable-winding drum.
Heretofore, with rigs of this type, there has been considerable trouble with the cable piling up on the drum adjacent its center instead of winding thereon evenly from side to side, and causing subsequent tangling of the cable or a too rapid run-out of the same, due to the piled up cable tending sooner or later to fall over to one side or the other.
It is therefore the principal object of my invention to eliminate this objectionable cable pileup by providing a spooling pulley over which the cable passes between'the boom pulley and the drum, and a means mounting said pulley so that it will automatically shift back and forth along the drum as the latter is rotated in a cable winding direction and insuring an even spooling of the cable along the drum from side to side thereof.
A further object is to provide a device for the purpose which will function with a minimum of which will be exceedingly effective for the purpose for which it is designed.
These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claim.
In the drawing similar characters of reference indicate corresponding parts in the several views:
Figure 1 is a fragmentary diagrammatic top plan of a well drilling rig, showing my improved cable spooling device mounted thereon.
Figure 2 is a side section on line 2-2 of Fig. 1, showing the position occupied by the boom when the spooling device is functioning.
Figure 3 is an enlarged fragmentary plan of the spooling pulley in section and a portion of the shaft on which it is mounted.
Referring now more particularly to the characters of reference on the drawing, the rig on which my improved spooling device is mounted comprises essentially a mounting or base frame structure I, a boom or walking beam having diverging side arms 2, a cable guide pulley 3 on the walking beam at its head end and a cable drum 4 onto which the cable 5 is wound.
The arms 2 are turnably mounted on the straight end portions 6 of a shaft which; is curyed intermediate its ends and for its-fullextentbetween said portions on a constant radius as at I; the end portions outwardly of arms 2 being supported against rotation in clamping boxes 8' mounted on the frame structure. The drum 4 is mounted on said structure below and somewhat ahead of the shaft; its length being substantially the same as the distance between the arms 2 at the shaft.
The spooling pulley 9 is mounted on the shaft between the arms 2 and is movable along and turnable on the curved portion of said shaft. In order that the pulley will thus readily move without either undue loose play or any tendency to bind, a relatively long bushing I0 is mounted in the hub ll of the pulley; said bushing being concavely bored intermediate its ends on a radius the same as the largest or convex radius of curvature of the shaft as at 12, and at its ends is convexly bored in the opposite direction on a radius the same as the smallest or concave radius 7 of curvature of the shaft as at 13. As a result, the bushing at the middle always engages the shaft on one side, while at its ends the bushing always engages the shaft on the opposite side, thus positively preventing rocking or binding of the bushing without interfering with its rotation: or movement alon the shaft. To aid in reducing friction, a grease cup 14 is mounted on the hub II to supply lubricant to the bushing bore. Since the pulley and bushing are of course always rotating, the opposed points of contact of drum, is substantially the same regardless of the position of pulley 9 along the curved portion 1 of the shaft. In other words, the length of cable between pulley 3 and the drum is always the same, and it is this featurewhich provides the even spooling of the cable from oneside to the other of the drum..
Since pulley 3 is disposed symmetrically'relative to therends of the drum and the rear shaft engaged ends of the arms the center of curvature 'of shaft portion 1 lies on a line centrally of and at right angles to the axis of pulley 3.
Since the said curved portion of the shaft, to function as desired, must lie in a plane substansubstantially fulfills the objects of the invention as set forth herein.
While this specification sets forth in detail the present and preferred construction of the device,
still in practice such deviations from such detail may be resorted to as do not form av departure from the spirit of the invention, as defined by the appended claim.
Having thus described my invention, what I claim as new and useful and desire to secure by Letters Patent is:
A cable spooling device comprising, with a relatively stationary cable-guide pulley and a cable drum spaced from said pulley; a cable spooling pulley disposed between the drum and guide pulley and means mounting the spooling pulley relative to the guide pulley and drum for guided movement lengthwise of the drum in a path such that the length of the portion of the cable from the guide pulley to the drum will be substantially the same from any point in the length of the drum; saidjpulleymountin'g meanscomprising a shaft having a constant curvature for the length of the drum and on which the spooling pulley is both turnable and axially movable, the pulley being concavely bored intermediate its ends on a curvature whose radius is that of the convex side of the shaft and at its ends is convexly bored on a'curvature' whose radius is that of the concave side of'the shaft.