US3494595A

US3494595A - Cable-to-hoist drum attachment mechanism

Info

Publication number: US3494595A
Application number: US740234A
Authority: US
Inventors: James P Bohan
Original assignee: United Aircraft Corp
Current assignee: Raytheon Technologies Corp
Priority date: 1968-06-26
Filing date: 1968-06-26
Publication date: 1970-02-10
Anticipated expiration: 1987-02-10

Description

Feb. 10, 1970 J, P, BOHAN v 3,494,595 I CABLE-TOHOIST DRUM ATTACHMENT MECHANISM Filed June 26, 1968 9 s sheets-sheer 1 r-l G l /Z j;

,f f /Z FIG 2 F|G-3 REM/,ND

A /J UNwrND il g/ if WV V' ff.

if f y/fz ,0f/'ORNE Y Feb.1o, 1970 J. P. Bol-'AN .3,494,595

CABLE-T0HOIST DRUM ATTACHMENT MECHANISM Filed June 26. 1968 3 Sheets-Sheet 2 Feb. 10, 1970 J. P. Bol-MN Y; 3,494,595

CABLE-TO-HOIST DRUM ATTACHMENT MECHANISM Filed June 26, 1968 v 3 Sheets-Sheet. 5

5&4 24

47m/@VEZ 'United States Patent O 3,494,595 CABLE-TO-HOIST DRUM ATTACHMENT MECHANISM James P. Bohan, Southport, Conn., assignor to United Aircraft Corporation, East Hartford, Conn., a corporation of Delaware Filed June 26, 1968, Ser. No. 740,234 Int. Cl. B66d l/00, 1/34 U.S. Cl. 254-150 9 Claims ABSTRACT OF THE DISCLOSURE A cable hoist system including a rotating drum having a continuous track mechanism in which a sliding block member is positioned for motion relative to the drum and with the cable end attached thereto and further including a blocking member which rotates with the drum and is biased to extend into the track passage and is contoured so that the sliding block member can pass thereby when moving in one direction within the track but cannot pass thereby in the other direction so that this arrangement not only connects the cable to the drum but permits the drum to rotate after the cable has been fully paid out without inadvertently rewinding the cable onto the drum in the opposite direction.

BACKGROUND OF THE INVENTION Field of invention This invention relates to mechanism for attaching the end of a cable to the hoist drum onto which the cable is to be wound and from which the cable is to be paid out and, more particularly, to such mechanism so that the drum can continue to rotate after the cable is fully paid out without rewinding the cable onto the drum in the opposite direction.

Description of the prior art In the cable hoist a-rt, the friction of the cable on the drum has been used to retain the cable on the drum and down-limit switches have been used to signal the pilot when the last three or so revolutions of the cable remain on the drum so that the pilot may stop the drum from rotating and thereby stop paying out cable and thereby avoid dropping the load. Experience has shown that these limit switches malfunction and that pilots, due to inadvertence or distraction, fail to heed their warning signal so that the drum continues to rotate and pay out the cable until the cable and load are lost from the drum.

In addition, the prior art constructions have positively anchored the cable end to the drum or reel and while this accomplishes the purpose of retaining the cable and its load, it presents a serious problem when the drum continues to rotate after the cable is fully paid out in that this continued rotation of the drum causes the cable to rewind onto the drum in the opposite direction and therefore inadvertently commences hoisting in the load.

SUMMARY OF INVENTION A primary object of the present invention is to provide an improved cable-to-hoist drum connection which not only prevents the cable and its pay load from being separated from the drum but also prevents the cable from being inadvertently rewound onto the drum if the drum should continue to -rotate after the cable has been fully paid out.

"ice

In accordance with the present invention, the drum is mounted for rotation in either direction so as to either wind in or pay out the cable and its load and is provided with a continues track or groove de'ning mechanism lwhich rotates with the drum and which carries a sliding block therewithin to which the cable end attaches to retain the cable attached to the drum. The invention further includes a block mechanism which is biased to extend into the track or groove and which is shaped so that the sliding block may pass thereby when moving with respect to the drum in one direction but is prevented from passing thereby when moving with respect to the drum in the opposite direction. This one directional or diode-type sliding block prevents the cable from being rewound onto the hoist drum or -reel when the drum continues to rotate after the cable is fully paid out and also permits the cable to be `wound upon the drum depending upon the direction of rotation of the drum.

`Other abjects and advantages will be apparent from the specication and claims and from the accompanying drawings which illustrate an embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevation of a modern helicopter of the crane type embodying my invention.

FIG. 2 is a showing of a hoist system including a cable and drum embodying my invention, and is partially broken away for purpose of illustration.

FIG. 3 is a side of the embodiment of my invention shown in FIG. 2 wherein the housing has been removed, the cable unwound, and the drum is partially broken away for purpose of illustration.

FIG. 4 is an enlarged partially broken away showing of a portion of my invention.

FIGS. 5, 6 and 7 are schematic showings of another embodiment of my invention for the purpose of illustrating the operation of the device.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 we see modern aircraft helicopter 10 of the crane type which consists of fuselage 12 supported from the landing strip by landing gear 14 and 16 and defining pilot compartment 18. Lift rotor 20 is supported for rotation from fuselage 12 and carries rotary blades or Wings 22 therewith to generate lift. Engine 24 drives rotor 20. Tail rotor 26, which performs the function of reacting the torque generated by lift rotor 20, is also driven through conventional drive mechanism 28 by engine 24.

Lift or hoist system 30 is supported in fuselage 12 and, as described hereinafter, carries a cable 32 with a conventional cargo hook 34 suspended from the end thereof to be attached to any load which is to be carried by helicopter 10. This load may be a passenger pod, a pallet of ammunition or the like.

Helicopter 10 may be of the type more fully described in U.S. Patent No. 2,925,130 and rotor 20, may be either 0f the articulated or rigid rotorl type disclosed in U.S. Patent Nos. 3,097,701 and 3,135,335, respectively. Blades 22 may be of the type more fully disclosed in U.S. Patent No- 3,333,642 and engine 24 and transmission therebetween to lift rotor 20 and anti-torque rotor 24 may be of f the type more fully described in U.S. Patent No.

Viewing FIGS. 2, 3 and 4 we see hoist system 30 in greater particularity. Hoist system 30 includes drum 40, which is preferably cylindrical and mounted for rotation in clockwise or counterclockwise direction about axis 42 by drive motor 44. The method of supporting and driving hoist drum or reel 40 is conventional and may be of the 3 type more fully disclosed in U.S. Patent No. 2,403,099. Cable 32 is either wound onto in spool fashion or paid out from drum 40 as the drum is caused to rotate in opposite directions. Disc members, such as 48, are positioned at the opposite ends of the cable receiving portion of drum 40 to prevent the cable from sliding off the ends of drum 40, and may or may not rotate therewith.

As explained above, it is an important teaching of this inventionto attach cable 32 to drum 40 so that the load being supported by the cable is not lost if the cable is fully paid out and also, so that if the drum continues to rtate after the cable is fully paid out the cable will not rewind upon the drum in the opposite direction from its normal winding action. The portion of my invention which permits this cable attachment and anti-rewind function is more fully disclosed in the broken away portions of FIGS. 2, 3 and 4 and includes continuous, annular track or slot 50, which is defined within drum 40 by drum `wall members 52 and therefore rotates with drum about axis 42, and sliding block member 54 which is loosely received in track 50 so that block 54 may slide Within track 50 with respect to drum 40, and still further includes stop, blocking or intercepting member 60, which is pivotally connected to drum 40 about pivot axis 62 and which is biased by spring 64, which extends between irum housing 52 and blocking member 60, to extend across continuous, circumferential slot or track 50 aS shown in FIGS. 3 and 4. Spring 64 could also be of the :oil type positioned about axis 62 and reacting against drum 40 to bias blocking members 60 to its FIG. 4 solid line position. It will be obvious that the cross-sectional shape of slot 50 may be any shape consistant with the shape of member 54.

By viewing FIGS. 3 and 4 it will be noticed that blocking member 60 is pivotally connected to rotating drum 40 at pivot axis 62 which is recessed in indented chamber 66in drum housing or wall member 52 so that, with spring 64 overcome, pivotable blocking member 60 can be recessed fully into recess chamber 66, as shown in phantom in FIG. 4, so as to clear track or slot passage 50 for the passage of sliding member 54 therepast. Member 60 may be gravity actuated but is preferably biased by a suitable mechanism such as spring 64. It will further be noted by viewing FIGS. 3 and 4 that blocking member 60 cannot move in a clockwise direction past its FIG. 3 and FIG. 4 (solid line) position in view of the fact that it abuts recess 70 in drum 40.

As best shown in FIGS. 3 and 4 itis important to note that blocking or intercepting member 60 is positioned, supported and selectively contoured so that it will not block the passage of sliding block 54 when the block 54 :ravels in a counterclockwise direction in track or slot 50 of drum 40 but will block the passage of sliding block 54 through track or slot 50 when drum 40 rotates in a :ounterclockwise direction. More specifically, if, as shOwn in FIGS. 3 and 4, drum 40 rotates in a clockwise direc- :ion withl respect to block 54, block 54 would contact :locking member 60 at angular surface 72 and overcome :he force of spring 64 and depress blocking member 60 into cavity 66 so as to permit the passage of sliding block 54 thereby. If, however, drum 40 rotates in a counter- :lockwise direction with respect to sliding block 54, when iliding block 54 reaches blocking member 60, its at iurface 74 comes into direct engagement with flat surface 76 of blocking member 60. Since blocking member 60 is VJrevented by the detent action of recesses 66 and 70 from Jivoting further in a clockwise direction as shown in FIGS. 3, and 4, blocking member 60 will prevent the Jassage of sliding block 54 therepast in track 50 with re- ;pect to drum 40 and block 54 will thereafter -rotate with lrum 40. Accordingly, it will be seen that sliding block i4 is free to pass blocking element 60 when drum 40 ro- :ates in a clockwise direction but is not free to pass elenent 60 when drum 40 rotates in a counterclockwise di- 'ection so that We, in effect, have a mechanical diode.

As best shown in FIGS. 3 and 4, the end of cable 32 opposite to the load carrying end is connected in any convenient fashion to sliding block 54 and extends therefrom through circumferential slot to the exterior of drum 40. It will be noted that circumferential slot 80 communicates with track 50 and also communicates with the exterior of drum or reel 40 so that cable 32 can pass therethrough unrestricted. Slot 80 is dened between drum 40 and end plate 82 which is attached thereto in spaced Irelation in conventional fashion and which may be formed in disc 48.

By way of operation of hoist system 30, let us assume that cable 32 is wound onto drum 40 as best shown in FIG. 2 and we wish to lower the load which is suspended from hook 34 at the end of cable 32.

To accomplish this cargo lowering function, the pilot will operate drive motor 44 and its associated mechanism to cause drum 40 to rotate in a clockwise direction as viewed in FIG. 3. This clockwise rotation of drum 40 will cause the Various layers of cable 32 `to be consecutively paid out from drum 40 until the cable is fully paid out and in the condition shown in FIG. 3. Since the nonload carrying end of the cable 32 is attached to drum 40 by sliding block 54 and is free to move within track 50 with sliding block 54 as the drum 40 continues to rotate in a clockwise direction when angular surface 72 of blocking member 60 eventually comes into contact with curved surface 78 of sliding block 54, and this will occur at the bottom of drum 40 since gravity will cause the free sliding block 54 to assume the bottom-of-thedrum position, blocking means 60 will be depressed into cavity 66 to permit the passage of blocking member 60 and sliding block 54 past each other so that drum 40 can continue to rotate in a clockwise direction without inadvertently rewinding cable 32 onto drum 40 in the opposite direction to its normal winding motion.

If, with cable 32 in its fully paid-out condition as shown in FIG. 3, the pilot wished to hoist the load or rewind the cable onto the drum 40, he actuates drive motor 44 so as to cause drum 40 to rotate in a counterclockwise direction as shown in FIG. 3 so that, with sliding block 54 and cable 32 remaining at the bottom of rotating drum 40, blocking member 60 will be carried with drum 40 in a counterclockwise direction until it eventually travels through almost 350 in that direction from its FIG. 3 position until atsurface 76 thereof contacts corresponding at surface 74 of sliding block 54, whereupon, due to the coaction of blocking member 60 against detents 70 and 66, blocking member 60 will prevent the passage of sliding block 54 therepast in track 50 and thereby cause sliding block S4 and hence cable 32 to rotate in a counterclockwise direction with drum 40 and thereby wind or rewind cable 32 onto drum 40.

A second embodiment of my invention is shown in FIGS. 5-7 and will not be described. Reference numerals have been used in FIGS. 5-7 which correspond wherever possible with the reference numerals already used to describe corresponding apparatus in the FIG. 2-4 construction. The FIG. 5-7 construction differs from the FIGS. 2-4 construction in that it utilizes two blocking members 60a and 60b which are pivotally connected to rotating drum 40 at pivot points 62a and 62b and which are biased toward one another by spring member 64, which may be either attached to both blocking members 60a and 60b as shown or may extend between

end discs

46 and 48 of drum 40 and the blocking members, or may be of t6he27 coil variety and concentric about pivot axes 62a and As ybest shown in FIG. 5 hoist drum 40 is rotating in a counterclockwise direction as indicated and carrying blocking members 60a and 60b therewith so that they extend across track 50 to block the passage of sliding block 54 thereby. Sliding blo-ck 54 is riding in the bottom of annular track 50 and is shown in FIG. 5 in a position where blocking members 60a and 60b are positively contacting sliding block 54 and carrying sliding block 54 and hence cable 32, which is attached to sliding block 54, therewith in counterclockwise rotation with drum 40 so as to vcause cable 32 to wind onto drum 40 in layer fashion, thereby hoisting the loadY which is attached to the other end of cable 32.

If it is desired to lower the load, the cable is caused to unwind from drum 40 by causing the drum to rotate in a clockwise direction as shown in FIGS. 6 and 7. After the last layer of cable 32 has been paid out, and drum 40 continues to rotate in a clockwise direction, blocking

members

60a and 62 will continue to rotate in that clockwise direction with drum 40 while sliding block 54 and cable 32 will ride in the bottom of circumferential track 50. Each time that blocking members 60a and 60b revolve so as to be at the bottom of drum 40, they encounter sliding block 54 and, due to their selectively contoured surfaces 72a and 72b, which coact with selectively contoured surfaces 78a and 78b of sliding block 54, blocking members 60a and 60h are caused to pivot about their pivot axes 62a and 62b into their FIG. 6 position to permit sliding block 52 and hence cable 32 to pass thereby in track 50 so that the continued clockwise rotation of drum 40 after cable 32 is fully paid out will not cause cable 32 to rewind onto drum 40 in the direction opposite to the normal cable winding action.

Hoist drum 40 is preferably housed in housing 90 as shown in FIG. 2. Should the pilot wish to release cable 32 and its load from drum 40 on an emergency basis, remotely actuatable guillotine assembly 92 is provided as best shown in FIGS. 2 and 3. Guilloti'ne assembly 92 may be of the knife-edge or scissors type.

While the invention has been described in the aircraft cable-hoist drum environment, it will be obvious to those having ordinary skill in the art that it is equally applicable to any environment in which a load carrying line or cable must be reeled-in and paid-out.

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.

I claim:

1. In a hoist system:

(l) a hoist drum mounted for rotation and adapted to have a load-carrying cable wound thereonto and paid out therefrom in response to drum rotation,

(2) means adapted to attach the end of the cable to the drum and to permit said drum to rotate after the cable has been fully paid out without having the cable rewind onto the drum comprising:

(a) continuous track slot-defining means adapted for rotation with said drum,

(b) a slidable member received loosely in said slot-defining means so as to be freely movable therearound and adapted to have the cable end attached thereto,

(c) stop means attached to said drum for rotation therewith and positioned and biased so as to extend into said slot-defining means and selectively shaped so that as said slidable member moves in said slot-defining means with respect to said drum in a first direction, said slidable member will displace said stop means and pass thereby and, further, so that as said slidable member moves with respect to said drum in said slot-defining means in the opposite direction, said slidable member will positively abut said stop means so that said slidable member thereafter is not free to move in said second direction with respect to said drum.

2. Apparatus according to claim 1 wherein said stop means is pivotally connected to said drum and spring biased so as to normally extend across said slot-defining means.

3. A hoist system including:

(1) a cyclindrical hoist drum mounted for rotation about an axis and including:

(a) a continuous circumferential track mechamsm,

(2) a slide member slidably connected to said track mechanism and free to move thereabout with respect to said hoist drum,

(3) an intercepting member pivotally connected to said hoist drum and biased so as to normally intercept the path of said slide member about said track mechanism and being selectively shaped so that said slide member will depress said intercepting member when travelling about said track mechanism in a rst direction so as to pass by said intercepting member and, further, so that said slide member will positively abut and be restrained by said intercepting member from further motion about said track mechanism with respect to said drum in the opposite direction,

(4) a hoist cable having one end connected to said slide member so as to move .therewith about said track mechanism and to be wound therefrom about said hoist drum so that as said drum is rotated in a rst direction, said cable is paid out from said drum to lower any load attached to the cable and, so that, when said cable is fully paid out from said drum said cable is still attached to said drum through said slide member and is able to move about said track mechanism with said slide member with respect to said drum as said drum continues to rotate in said first direction without rewinding onto said drum, and, further so that, as said drum is rotated in the opposite direction, said slide member will abut said stop member and be prevented from further motion thereby about said track mechanism so that said cable will Wind onto said hoist drum, thereby elevating any load attached from the cable.

4. Apparatus according to claim 3 and including means to cause said hoist dnum to rotate in both a clockwise and a counterclockwise direction.

5. Apparatus according to claim 3 wherein said track mechanism is a continuous annular chamber concentric about said drum axis of rotation and positioned within said drum and is of substantially rectangular cross-section to receive said slide member and which includes a circumferential slot communicating therewith and with the exterior of said drum and through which slot said cable Ipasses and is free to travel with respect to said drum as 4said slide member moves with respect to said drum.

6. A cable hoist system including:

(l) a hoist drum mounted for rotation about an axis So that cable may be paid out therefrom or wound thereonto as said drum is rotated about said axis, and including:

(a) a continuous track means extending around said drum,

(2) sliding block means slidably connected to said track means for motion thereabout with respect to said drum and adapted to receive a cable end,

(3) blocking means connected to said drum for rotation therewith and positioned with respect to said track means and shaped to permit passage of said sliding block therepast with respect to said dnum in a first direction and to Iprevent passage of said sliding block therepast with respect to said drum in the opposite direction.

7. In a hoist system:

(1) a hoist drum mounted for rotation and adapted to have a load-carrying cable wound thereonto and paid out therefrom in response to drum rotation,

(2) continuous track means connected to said drum for rotation therewith,

7 (3) means adapted to connect the end of the vcable to the said track means and to slidably carry the cable end in said track means when said cable has been fully paid out to thereby prevent the cable rewinding onto the drum. 8. Apparatus according to claim 7 and including rousing means to house said hoist drum.

9. Apparatus according to claim. 7 and including means )peratively associated with said hoist drum and actuatable o disconnect the cable from the hoist drum.

8 References Cited UNITED STATES PATENTS s/1953 Badik 242-1-117 7/1956 sarah 242-125.1