US3078060A

US3078060A - Fleet angle correction apparatus

Info

Publication number: US3078060A
Application number: US58988A
Authority: US
Inventors: Sr Franklin L Le Bus
Original assignee: LE BUS ROYALTY CO
Current assignee: LE BUS ROYALTY CO
Priority date: 1960-09-28
Filing date: 1960-09-28
Publication date: 1963-02-19
Anticipated expiration: 1980-02-19

Description

Feb. 19, 1963 F. LE BUS, SR 3,07

FLEET ANGLE CORRECTION APPARATUS Filed Sept. 28, 1960 2 Sheets-Sheet l ,F (Zg. 2.

INVENTOR. F L. Le BUS 5R.

Feb. 19, 1963 F. L. LE Bus, SR 3,073,060

FLEET ANGLE CORRECTION APPARATUS Filed Sept. 28, 1960 2 Sheets-Sheet 2 W INVENTOR. F L. L e B U 5 SP.

ATT ORNE Y 3,078,060 FLEET ANGLE CQRRECTH'GN APPARATUS Franklin L. Le Bus, Sr., Longview, Tern, assignor to Le Bus Royalty Company, Longview, Tera, a partnership Filed Sept. 28, 196i Ser. No. 58388 6 Claims. (Cl. 242l57.l)

This invention relates to improvements in cable spooling apparatus and more particularly, but not by way of limitation, to a cable reeving apparatus particularly designed and constructed for correcting the fleet angle of the cable, whereby the cable may be spooled on the drum efliciently and evenly without distortion or entangling of the cable during the winding operation.

Many problems are encountered in the winding or spooling of a wire line or cable onto a drum. The cable having a bad fleet angle from the stationary sheave to the drum core has a tendency to wind unevenly on the core of the drum, which results in a jerking and tangling of the cable as it is unspooled. This is a particular disadvantage in a housing or cable winding operation wherein a relatively short mast is utilized with a relatively long spooling drum. Under this type of circumstances, the fleet angle of the cable between the fixed sheave and the drum is usually extremely excessive or bad, and it is very diflicult to maintain a control of the spooling operation. In addition, it is important that each layer of the cable extend across the drum core from flange to flange with each successive wrap or turn of each layer of the cable being disposed in a close relationship to the adjacent wrap without piling up or laying on top of each other other in the proximity of the flange, or pile up in the middle or either side of the drum core between the flanges. It is diflicult to control the Winding of the cable with the successive turns close together, particularly in well bore drilling operations wherein the load on the cable frequently causes a twisting of the cable. If the initial layer of the cable is inefliciently wound on the drum, and the fleet angle is bad, the error will be increased with each successive layer until the control of the cable Will be substantially lost.

Many elforts have been made to improve the efliciency of the cable winding operation. Frequently, an operator will stand in the vicinity of the drum as the cable having a bad fleet angle is being spooled thereon, and with the assistance of a crowbar, or the like, will attempt to manually guide the cable and correct or overcome the bad fleet angle, which is obviously ineflicient and dangerous. As a result, many devices have been developed for guiding the cable. However, for the most part, these devices have not solved the problem in that there is frequently a manual operation thereof required, or the structure provides a considerable amount of friction which must be overcome during the operation thereof, thus greatly reducing the eficiency of operation.

The present invention contemplates a novel fleet angle control apparatus providing for an automatic operation in accordance with the pressure or tension of the cable to maintain a smooth and even spooling operation. The friction in the operation of the novel reeving device for eliminating fleet angle of the lines as it is reeved onto the drum is reduced to a minimum for optimum efliciency of control of the cable during the winding thereof onto the drum. The cable passes over a movable sheave particularly designed to move laterally in response to pressure of the cable whereby the cable is orientated with respect to the drum at the optimum angle therebetweeen for providing an eflicient spooling thereof. The present invention may be utilized for controlling the spooling operation, as well as correcting the fleet angle of the cable. However, it is preferable to utilize the novel apparatus Patented Feb. 19, 1953 in combination with a grooved or controlled spooling drum, thus assuring a complete and eflicient spooling of the cable.

The sheave is rotatably journalled on and movable along a shiftable shaft, which is carried by a substantially accordion type linkage mechanism whereby the angular disposition of the shaft may vary in accordance with the longitudinal movement of the sheave therealong. The plane of the sheave is automatically maintained substantially parallel with the pull point of the cable as it leaves the drum. The linkage mechanism is provided with oppositely acting link arms which permit the shaft to vary in angular disposition with respect to the axis of the drum, but substantially precludes any lateral shifting of the shaft. In other words, the shaft will remain within substantially the same longitudinal confines, but will pivot about the center point of the longitudinal axis thereof. This permits the installation of the fleet angle correction apparatus in juxtaposition to the drum in a minimum of lateral area. In addition, the linkage mechanism is provided with a pivotal connection to a base member, or base structure, whereby vertical fluctuations or adjustments of the shaft are automatically provided in accordance with the inherent vibrations and movement of the cable during the spooling operation. Furthermore, the vertical adjustment of the shaft greatly improves the efliciency of the spooling of multiple layers of cable on the drum.

The movable sheave cooperates with a stationary sheave for automatically maintaining a substantially perpendicular path for the cable with respect to the axis of the drum during the winding operation. Thus, if the first layer of cable is properly spooled onto the drum, this invention assures an eflicient spooling of the cable for any additional layers of the line wraps regardless of excessive fieet angles without any entanglement of the line. The movable pulley responds to the normal action of the cable for automatically adjusting to maintain a constant length for the cable between the stationary sheave and the drum if the first or controlled layer of wraps is properly spooled, thus facilitating the true and accurate multi-layer winding of the cable on the drum. The control of the fleet angle in the winding of the cable with the novel reeving apparatus assures that there is a level and accurate and non-distorted winding of any number of layers of the line on the drum at all angles, regardless of what the fleet angle may be.

It is an important object of this invention to provide a novel reeving apparatus for controlling the fleet angle during the spooling of a line into a drum in a true and accurate manner for substantially eliminating any distortion or entanglement of the cable during the spooling operation.

It is another object of this invention to provide a reeving apparatus wherein the control of the fleet angle during the winding of the cable onto the drum is automatic, thereby eliminating human errors inherent in a manual operation.

It is another object of this invention to provide a novel reeving apparatus wherein the friction from a bad fleet angle during the operation thereof is reduced to a minimum for greatly increasing the efliciency thereof.

Another object of this invention is to provide a reeving apparatus particularly designed and constructed to provide an automatic control of the fleet angle during the spooling of the cable whereby the cable will be maintained substantially perpendicular to the axis of the drum throughout the spoolin g operation.

Still another object of this invention is to provide a reeving apparatus to substantially eliminate fleet angle wherein the length of the cable between the drum and the stationary sheave is constant throughout the winding of the cable onto the drum.

It is a further object of this invention to provide a fleet angle correction apparatus which may be secured in juxtaposition to a drum in a minimum of space.

It is a still further object of this invention to provide a novel fleet angle control apparatus which is simple in both operation and construction with a resultant increased efficiency in the control of the cable spooling operation.

Other objects and advantages of the invention will be evident from the following detailed description, read in conjunction with the accompanying drawings, which illustrate my invention.

In the drawings:

FiGURE l is a side elevational view of a fleet angle control apparatus embodying the invention.

FIGURE 2 is a plan view of a fleet angle correction apparatus embodying the invention, and depicting one position thereof during the cable spooling operation.

FIGURE 3 is a view similar to FIG. 2 showing another position of the cable spooling operation.

FIGURE 4 is a view similar to FIG. 2 depicting still another position of the cable spooling operation.

Referring to the drawings in detail, reference character generally indicates a drum or winch having a cable 12 spooled thereon. The drum 10 may be journalled on a suitable shaft 14 for rotation, and is provided with

opposed end flanges

16 and 18 as is well known. It is preferable that the drum be provided With a core 20 (FIG. 4) having a plurality of cable receiving grooves 22 on the outer periphery thereof for facilitating the winding or spooling of the first layer or Wrap of the cable 12 onto the drum 16, as is well known in the industry. However, it is to be noted that any suitable drum or winch may be utilized with the invention.

A fleet angle correction or cable reeving apparatus, generally indicated at 24, is secured in juxtaposition to the drum 10, as will be hereinafter set forth, and is interposed between the drum 1%} and a fixed position sheave 26 (FIG. 1). The cable 12 extends from the drum 10, through the reeving apparatus or fleet angle correction apparatus 24, around the sheave 26, and thence to the load (not shown) being manipulated thereby. The sheave 26 may be secured to a support member 28 in any suitable manner, such as by a pair of spaced link arms 36, only one of which is shown, and which are pivotally secured at 32 to a bracket member 34. The sheave 26 rotates about an axis or pin 36 and the pivotal connection of the link arms 30 in combination with the weight of the sheave 26 permits the sheave to move in a counterclockwise direction about the pivot 32 substantially instantaneously with a release of tension on the cable 12 whereby the cable will be clamped between the sheave 26 and the bracket 34. The clamping of the cable will substantially preclude slack in the cable 12 from being transmitted to the drum 10. It will be apparent that the pivotal mounting of the sheave 26 is preferred, but substantially any conventional type of fixed position sheave may be utilized with the drum 10 and reeving apparatus 24.

The fleet angle correction apparatus 24 comprises a circular rod or shaft 38 having a transversely movable sheave or pulley 40 journalled thereon in any suitable manner (not shown). The opposed ends of the shaft 38 are flattened or reduced as at 42 and 43 for receiving one end of substantially identical pivot arms or

link members

44 and 46. The link member 46 preferably comprises an upper link 46 and a spaced lower link member 46', as shown in FIG. 1, pivotally secured to the opposed sides of the end 42 by a pivot pin 48. The link arm 44 is preferably of a similar construction, and is pivotally secured to the end portion 43 by a pivot pin 50. The opposite ends of the spaced link members 46 and 46' are pivotally secured at 52 to one end 54 of an adjustable tie bar 56. The link member 44 is similarly secured to the opposite end 53 of the bar 56 by a pivot pin 60. The tie bar 56 may be of a unitary construction, if desired. However, it has been found preferable to provide a pair of inwardly directed

bar members

62 and 64 threadedly secured to a centrally disposed turnbuckle 66 in any well known manner whereby the overall length of the tie bar 56 may be adjusted for spacing the pivot points 52 and 60 at the optimum distance according to the utilization of the reeving apparatus 24.

A second pair of spaced pivotal

link arm members

68 and 70 are secured to the ends 54 and 58, respectively, of the tie bar 56 and are oppositely disposed from the

arms

46 and 44. The arm or link member 68 preferably comprises an upper link 68 and a spaced lower link 68 (FIG. 1) pivotally secured to the opposed sides of the end portion 54 by a pivot pin 72. The link arm 70 is preferably of a similar construction and is secured to the end portion 58 by a pivot pin 74. The opposite ends of the arms 68 and 68' are pivotally secured at 76 to an outwardly extending bracket member 78. The opposite end of the arm 70 is similarly secured to a second bracket by a pivot pin 82. It will be apparent that the

arms

68 and 70 co-act in opposite directions from the

arms

44 and 46 with respect to the tie bar 56, thus providing a substantially accordion type action for the fleet angle correction apparatus 24, as will be hereinafter set forth in detail. The

brackets

78 and 80 are spaced on a bar member 84 and rigidly secured thereto in any suitable manner (not shown) whereby the pivot pins 78 and 80 will be in substantial alignment with the pivot pins 48 and 50 for a purpose as will be hereinafter set forth. The bar member 84 is preferably constructed from an angle iron, or the like, and is provided with a pair of spaced downwardly depending flange members 86 and 83 for receiving aligned pivot pins 90, only one of which is shown (FIG. 1), whereby the bar 84 may be pivotally secured between a pair of spaced outwardly extending bracket members 92, only one of which is shown, for supporting the entire reeving apparatus 24. The pivot pins 90 are disposed in substantially the same longitudinal axis, as indicated by the line 94, whereby a pivotal action is provided for the bar 84, thus transmitting a pivotal action for the entire apparatus 24.

The cable 12 extends from the drum 10, under the movable sheave 40 and under the fixed position sheave 26 and to the load (not shown) being manipulated thereby. As the cable 12 progresses in a transverse direction across the drum core 20 during the spooling or unspooling operation, as will be hereinafter set forth, the reeving apparatus 24 automatically shifts for permitting movement of the pulley 40' transversely in accordance with the pull or tension of the cable 12. The pressure of the cable 12 and the correction of movable sheave 40 on the shaft 38 automatically changes the angular disposition of the shaft through the action of the

pivot arms

44, 46, 68 and 70. This is caused by the accordion type action of the reeving apparatus 24. The cable or line 12 pulls the sheave 40, the sheave 40 does not pull the line. The tension in the cable 12 is the important feature in the eflicient operation of the apparatus 24. Furthermore, it will be apparent that any suitable type of friction guide member (not shown) may be utilized in lieu of the sheave 40.

A pair of outwardly extending

flange members

89 and 91 are secured to the bar 84 each spaced outwardly thereon from the

pivotal arms

68 and 70, respectively, as shown in FIGS. 2, 3 and 4. An adjustable stop member, such as the threaded stud 93, extends transversely through the flange 89 in order to limit the clockwise rotation of the arm 68 about the pivot 76. A similar stop member extends transversely through the flange 91 for limiting the counter-clockwise rotation of the arm 70 about the pivot 82. It will be apparent that the

stop members

93 and 95 are optional and may be omitted, if desired.

Operation In order to effect the compensation of the fleet angle or correction of the cable 12 for assuring an efficient spooling or unspooling operation, the reeving apparatus 24- is interposed between the drum and the fixed position sheave 26 whereby the movable sheave 40 receives the cable thereunder, as particularly depicted in FIG. 1. Any movement of the cable to the left or right of the mean or center point 96 (FIG. 3) of the drum 10 will cause the correction pulley 4G to move to either the left or right of the center point in accordance with the direction of the spooling, or unspooling of the line or cable. The pressure of the cable 12 and the sheave 413 changes the angular disposition of the shaft 38, as clearly shown in FIGS. 2, 3 and 4, whereby the sheave 40 will always be in substantial parallel alignment with the pull point of the cable 12 coming off the drum 10. This is caused by the accordion type action of the

arms

44, 46, 68 and 70 in cooperation with the tie bar 56.

The friction contact of the cable being wound on the drum exerts a pressure through the cable which is transmitted to one side of the sheave 40, thus causing the sheave 40 to move in the direction in which the pressure is exerted. Since the sheave 41! is transversely movable on the shaft 33, the sheave will follow the pressure, and move along the shaft 38 in accordance with the winding of the cable on the drum, or unwinding thereof, as desired. Therefore, if the cable 12 is moved from a left to a right position, as shown in FIG. 2, the winding of the drum 10 is toward the right flange 1S, and the sheave 40 will move along the shaft 33 in a right hand direction due to the pressure of the cable acting against the portion 98 of the sheave. This movement of the sheave 40 along the shaft 38 pulls the pivot pin 48 in a direction toward the drum 10, whereby the

pivot arms

46 and 68 tend to seek a substantially straight line in cooperation with the end 54 of the tie bar 56. Simultaneously, the tie bar 56 will move in a left hand direction (FIG. 2) whereby the pivot pins 60 and 74 will move outwardly for collapsing or providing an accordion type action between the arms 44 and 74). This accordion action of the arms 44 and '70 permits the shaft 38 to shift angularly, thus maintaining the plane of the sheave 40 substantially parallel with the pull point of the cable moving onto the drum, whereby the cable is maintained in a line substantially perpendicular to the axis of the drum 1%.

Similarly, when the cable is moving in a left hand direction, or toward the flange 16, such as in the unspooling operation depicted in FIG. 4, the pressure of the cable 12 acting against the portion 1% of the sheave 49 moves the sheave along the shaft 38 in a left hand direction whereby the pivot pin 50 is urged in a direction toward the drum It). This action tends to straighten the arms 44 and 7t} in combination with the end portion 58 of the tie bar, as shown in FIG. 4. Simultaneously, the tie bar 56 will shift or move into a right hand direction to provide an accordion action for the

arms

46 and 68. This permits the pivot pin 48 to move in a direction away from the drum for reversing the angular shifting of the shaft 38. It will be apparent that the angular shifting of the shaft 33 is continual as the sheave 40 moves longitudinally therealong, thus maintaining the cable in a substantially perpendicular path with respect to the axis of the drum 10. The tie bar 56 reciprocates in response to the movement of the sheave 40 along the shaft for adjusting the arms 44, 7t), 46 and 68. As shown in FIG. 3, when the cable 12 is in the substantial center 96 of the drum 16, both the arms 44 and 7t and the

arms

46 and 68 will be flexed slightly outwardly, and the relative position therebetween will be constantly adjusted or changed throughout the spooling or unspooling of the cable on the drum 19. Furthermore, due to the accordion action of the reeving apparatus 24, and particularly the fact that the pivot pins 78 and 80 are in substantial alignment with the pivot pins 4S and 54 there will be substantially no lateral movement of the shaft during the angular shifting or movement thereof.

The length of the cable 12 between the tangent point A (FIG. 1) of the fixed position sheave 26 and the tangent point C of the drum core 20 remains constant, and the movable sheave 40, which divides the cable portion A-C into two sections, namely A-B and B-C, maintains the constant length for the cable portion A-C. As the sheave 49 moves along the shaft 38 in either direction from the center position thereof, it will be apparent that the fleet angle (not shown) between the fixed position sheave 26 and the movable sheave 40 will increase, whereby the length of the cable portion A-B will increase, and the cable portion B-C will simultaneously shorten by a corresponding amount. However, the combined lengths of the cable portions A-B and BC will always remain the same or remain constant throughout the cable spooling operation. This is caused by the shifting of the angular axis of the shaft 38.

The same pressure in the cable that causes the movement of the sheave 40 is sufficient to cause a pivoting of the shaft so that the pivot pin 51 on the end 43 of the shaft 38 moves in a direction toward the drum as the sheave 4t} nears or moves toward the pin 50 and the flange 16. Conversely, the pivot pin 48 on the opposite end 42 of the shaft will move in a direction away from the drum. Similarly, when the sheave 4i approaches the pin 48 and the flange 18, the pin 48 will be moved in a direction toward the drum and the pin 50 will move in a direction away from the drum. This angular shifting of the shaft 38 is accomplished through the accordion action of the

linkage members

44, 46, 68 and 7t) and the tie bar 56. It is to be noted, however, that the overall length of the cable portion A-C remains constant regardless of the longitudinal position of the sheave 40 on the shaft 38.

The stop members 93 and are provided in order to assure an eflicient reversal of the cable 12 as the cable nears the

drum flange

16 or 18. For example, as the cable 12 nears the left hand flange 16 (FIG. 4), the shifting of the shaft 38 brings the pivot arm 68 into contact with the stop member 93. This precludes any further outward movement of the arm 68, and the cable 12 then reverses the direction of transverse travel on the drum and begins the return wrap across the drum. Conversely, when the cable nears the right hand flange 18 (FIG. 2), the angular shifting of the shaft 38 brings the arm 70 into contact with the stop member 95. This precludes any further outward movement of the arm 76, and the cable 12 will then reverse in movement to begin the return wrap on the drum. Of course, the helical grooves 22 on the drum core 29 are normally designed and constructed for providing a cross-over action of the cable 12 at each drum flange, but the

stop members

93 and 95 are provided to facilitate the reversal action of the cable.

The pivotal action of the bar 84 about the axis 94 transmits a vertical movement of the entire reeving apparatus 24 during the spooling or unspooling operation. This permits the shaft 38 to automatically adjust or assume the optimum position with respect to the drum, particularly during the winding of multiple layers of cable thereon. It has been found during the operation of the apparatus 24 that the entire apparatus fluctuates substantially continually in a vertical direction during the spooling operation due to the inherent vibrations of the cable. This vertical play or vertical pivotal movement of the bar 84 permits an automatic adjustment of the shaft 38 in the vertical direction for greatly increasing the efficient operation of the reeving apparatus 24. In addition, in the event the load on the cable, or tension in the cable is suddenly released or decreased, the fixed position sheave 26 will drop downwardly or rotate in a counter-clockwise direction about the pivot pin 32 and clamp the cable between the sheave 26 and the bracket 34 to reduce any slack in the line in the proximity of the drum. Simultaneously, the

emaoeo pivotal action of the bar 84 will permit the entire fleet angle control apparatus 24 to rotate in a clockwise direction about the pivot axis 94 for maintaining the cable 12 in a taut position around the sheave 40.

By way of summary, the fleet angle correction apparatus 24 automatically corrects the fleet angle of the cable coming from the fixed position sheave 26 and maintains the cable in a substantially perpendicular relationship with regard to the axis of the drum during the spooling or unspooling operation. The pressure of the cable passing under the movable sheave 4t) automatically causes an adjustment of angular shifting of the shaft 33 simultaneously with a transverse movement of the sheave 40 therealong for maintaining the sheave 44] in a constant parallel alignment with the pull point of the cable on the drum. The accordion action of the reeving apparatus 24 provides for an angular shifting of the shaft 38 in response to the movement of the sheave 4%) therealong for maintaining the length of the cable between the drum and the fixed position sheave 26 constant throughout the spooling operation. The piling up of the cable at the flanges upon the reversing of the winding at the end and beginning of each layer is eliminated by the limitation of the left and right hand movement of the fleet angle control apparatus. Thus, the winding of the cable onto the drum, or unwinding thereof, is controlled automatically to provide a true and accurate winding, layer after layer. In addition, the entire reeving apparatus is pivotally mounted for a vertical movement to provide an automatic vertical movement or shifting of the shaft 38 and sheave 40 in response to the position and pressure of the cable during the spooling operation.

From the foregoing, it will be apparent that the present invention provides a novel reeving apparatus for the correction or compensation of the fleet angle in the spooling or unspooling of a line from a winch or drum for effecting an eflicient winding of the line onto the drum without any distortion or entanglement thereof. The novel reeving apparatus is automatically shifted by the pressure of the cable or line being spooled for maintaining the line substantially perpendicular to the axis of the drum throughout the spooling operation. This angular shifting of the shaft effects the position of the movable sheave thereon for correcting the fleet angle accordingly. The limitation of the left and right hand movement of the apparatus facilitates the reversal of the cable at the end and beginning of each layer for substantially eliminating any piling up of the cable adjacent the drum flanges. Furthermore, vertical fluctuations of the shaft are automatic in response to the position and pressure or tension in the cable for assuring a completely automatic control of the spooling operation and a simultaneous correction of the fleet angle of the cable throughout the winding or unwinding thereof.

Changes may be made in the combination and arrangement of parts as heretofore set forth in the specification and shown in the drawings, it being understood that any modification in the precise embodiment of the invention may be made within the scope of the following claims without departing from the spirit of the invention.

1 claim:

1. In combination with the drum having a cable wound thereon, a fleet angle corrector apparatus comprising a shaft, a movable sheave journalled on the shaft for receiving the cable, a double acting linkage mechanism pivotally secured to each end of the shaft, said linkage mechanism comprising a first pair of oppositely acting link members pivotally secured at one end of the shaft, a second pair of oppositely acting link members pivotally secured to the opposite end of the shaft, adjustable means extending between the said pairs of link members and a greater length than the length of the shaft whereby the action of the first of said pairs is reversed to the action of the second of said pairs for substantially precluding longitudinal shifting of the shaft, said sheave responsive to pressure of the cable for moving longitudinally along the shaft, said linkage mechanism providing for an angular shifting of the shaft in response to the movement of the sheave therealong for maintaining the plane of the sheave substantially parallel with the pull point of the cable from the drum, and means providing for vertical movement of the shaft upon winding and unwinding of multiple layers of cable on the drum.

2. In combination with the drum having a cable wound thereon, a fleet angle corrector apparatus comprising a shaft, movable sheave journalled on the shaft for receiving the cable, a double acting linkage mechanism pivotally secured to each end of the shaft, said sheave responsive to pressure of the cable for moving longitudinally along the shaft, said linkage mechanism provided with oppositely acting pairs of link members having adjustable tie bar means therebetween of a length greater than the length of the shaft for an angular shifting of the shaft with substantially no longitudinal movement thereof in response to the movement of the sheave therealong for maintaining the plane of the sheave substantially parallel with the pull point of the cable from the drum, and means moving the shaft for automatic adjustment thereof upon winding and unwinding of multiple layers of cable on the drum.

3. In combination with the drum having a cable wound thereon, a fleet angle corrector apparatus comprising a shaft, a movable sheave journalled on the shaft for receiving the cable, a double acting linkage mechanism pivotally secured to each end of the shaft and comprising oppositely acting pairs of pivotal link members having adjustable connecting means therebetween of a length greater than the length of the shaft for assuring a reverse movement between the said pairs of link members, said sheave responsive to pressure of the cable for moving longitudinally along the shaft, said linkage mechanism providing for an angular shifting to the sheave with substantially no longitudinal movement thereof in response to the movement of the sheave therealong for maintaining the plane of the sheave substantially parallel with the pull point of the cable from the drum, and means providing for automatic vertical adjustment of the shaft upon winding and unwinding of multiple layers of the cable on the drum.

4. A fleet angle control apparatus comprising a shaft, a movable sheave journalled on the shaft and interposed between a drum and a fixed position sheave having a cable extending therebetween, a double acting linkage mechanism pivotally secured to the shaft, said movable sheave responsive to pressure of the cable for moving longitudinally along the shaft as the cable is wound onto the drum, said linkage mechanism comprising an adjustable tie bar member of a length greater than the length of the shaft and having a pair of opposed link arms pivotally secured to each end thereof, said link arms operable in reverse directions for controlling the shifting movements of the shaft, said linkage mechanism responsive to movement of the movable sheave along the shaft for angular shifting of the shaft with respect to the axis of the drum with substantially no longitudinal movement of the shaft, said shifting of said shaft maintaining the movable sheave in a plane substantially perpendicular to the axis of the drum, and means providing for vertical movement of the shaft upon the Winding of multiple layers of cable on the drum.

5. A fleet angle control apparatus comprising a shaft, a movable sheave journalled on the shaft and interposed between a drum and a fixed position sheave having a cable extending therebetween, a double acting linkage mechanism of a substantially accordion-ty e arrangement pivotally secured to the shaft, said movable sheave responsive to pressure of the cable for moving longitudinally along the shaft as the cable is wound onto the drum, said linkage mechanism comprising a tie bar of a length greater than the length of the shaft and having a pair of opposed link arms pivotally secured to each end thereof, said pairs of link arms connected between the shaft and a base member whereby the said pivotal connections are in substantial alignment, said linkage mechanism responsive to movement of the movable sheave along the shaft for angular shifting of the shaft with respect to the axis of the drum with substantially no longitudinal movement of the shaft, said shifting of said shaft maintaining the movable sheave in a plane substantially perpendicular to the axis of the drum, and means providing for vertical movement of the shaft upon the winding of multiple layers of cable on the drum.

6. A fleet angle control apparatus comprising a tie bar, a pair of pivotal link members carried by one end of the bar, a second pair of pivotal link members carried by the opposite end of the bar, a shaft pivotally secured to one of each of said pairs of link arms, the other of each of said pairs of link arms pivotally secured to a support member with the pivotal connection thereof in substantial alignment with the pivotal connection of the first of said link arms with the shaft, 21 sheave joumalled on the shaft and movable therealong, said shaft movable in variable angular dispositions in response to the movement of the sheave therealong, said support member pivotally secured for vertical movement to provide for automatic vertical fluctuations of the shaft, and said tie bar of a length greater than the length of the shaft whereby longitudinal shifting of the shaft is substantially eliminated.

References Cited in the file of this patent UNITED STATES PATENTS 1,684,367 Foster Sept. 11, 1928 2,595,584 Jones May 6, 1952 2,660,382 Wilson Nov. 24, 1953 2,855,163 Powers Oct. 7, 1958 FOREIGN PATENTS 686,105 Germany Jan. 3, 1940

Claims

1. IN COMBINATION WITH THE DRUM HAVING A CABLE WOUND THEREON, A FLEET ANGLE CORRECTOR APPARATUS COMPRISING A SHAFT, MOVABLE SHEAVE JOURNALLED ON THE SHAFT FOR RECEIVING THE CABLE, A DOUBLE ACTING LINKAGE MECHANISM PIVOTALLY SECURED TO EACH END OF THE SHAFT, SAID LINKAGE MECHANISM COMPRISING A FIRST PAIR OF OPPOSITELY ACTING LINK MEMBERS PIVOTALLY SECURED AT ONE END OF THE SHAFT, A SECOND PAIR OF OPPOSITELY ACTING LINK MEMBERS PIVOTALLY SECURED TO THE OPPOSITE END OF THE SHAFT, ADJUSTABLE MEANS EXTENDING BETWEEN THE SAID PAIRS OF LINK MEMBERS AND A GREATER LENGTH THAN THE LENGTH OF THE SHAFT WHEREBY THE ACTION OF THE FIRST OF SAID PAIRS IS REVERSED TO THE ACTION OF THE SECOND OF SAID PAIRS FOR SUBSTANTIALLY PRECLUDING