US2303002A

US2303002A - Tag-line device

Info

Publication number: US2303002A
Application number: US383968A
Authority: US
Inventors: Ruddock William
Original assignee: McCaffrey Ruddock Tagline Corp
Current assignee: McCaffrey Ruddock Tagline Corp
Priority date: 1941-03-18
Filing date: 1941-03-18
Publication date: 1942-11-24
Anticipated expiration: 1959-11-24
Also published as: BE474018A; ES178745A1

Description

' Nov. 24, 1942. L

W; RUDDOCK 0 TAGLINE DEVICE Fi led March 1 1941 2 Sheets-Sheet l INVENTOR: 41AM Bannock, W

ATTORNEYS.

w. RUDDOCK 2,303,002

TAGLINE DEVICE Nov. 24, 1942.

Filed March 18. 1941 2 Sheets-She et z INVENTOR: MAL/AM .(Puaaoax,

' ATTORNEYS.

Patented Nov. 24, 1942 William Ruddock, South Pasadena,

or, by direct and mesne assignmen Ruddock Tagline Corporation, Los

Calif., assignts, to The Angeles, Calif., a corporation of California Application March 18, 1941, Serial No. 383,968

5 Claims.

This invention relates to material handling devices, such as crane mechanisms and the like, and

particularly to mechanisms for preventing a bucket, or other material engaging device suspended from a boom, from turning or spinning in operation. Such mechanisms are commonly known as taglines.

In order to prevent turning of the bucket, it has been customary. to fasten. a line to a portion of the bucket and to provide some means. for maintaining the line under tension during operation of the crane. In-the" past, this has been done by the utilization of counterweights sliding on the boom, but such mechanisms are ineffective when the boom approaches a horizontal position. Spring driven reels, attached to the boom, winding the tagline to maintain it under tension have also been used, and work very well. .MyUnited States Patent No. 2,166,479, shows one form of spring driven tagline device. This type of mechanism is subject to limitation in use, however, in that any turning effort on the spring in the direction of winding tends to snap or kink the spring.

Coiled springs, used to produce a torque, are very easily broken by any torque tending to unwind them, and when the line parts or becomes detached from the bucket, the reel, free of any restraining influence, tends to spin. Because of its high rotational inertia, such spinning wil1 cause it to continue turning after the spring has reached its neutral condition, thus kinking the spring, often so badly that it cannot be removed from the casing, thus renderingthe entire device useless.

When lifting magnetic materials with a lifting electromagnet operated by a crane, in addition to the provision of means for preventing the hoisting lines from twisting by reason of the magnet spinning, some provision must bemade to prevent the electric cables leading to the magnet from breaking. As the cable is relatively weak, it must be held clear of obstructions, and at the same time, must not be placed under undue tension. Various makeshift methods have been employed in accomplishing this result, none of which are very satisfactory. 7

It is therefore an object of the present invention to provide a tagline reel which wi11 not be damaged by parting of the tagline.

It is a further object of the present invention to provide a tagline reel which willprotect the power cable of a lifting magnet.

It is a further object of the present invention to provide a tagline' device in which the'tension on the line can be readily increased without the necessity of coiling the line for insertion over the reel.

It is a further object of the present invention to provide a tagline reel in which the spring can be readily replaced.

This invention possesses many other advantages and has other objects which may be made more easily apparent from a consideration of one embodiment of the invention. For this purpose there is shown a form in th drawing accompanyingand forming part of the present specification. This form will now bedescribed in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since. the scope of the invention is best defined by the appended claims.

Figure 1 is a side elevation of part of a crane, showing the device of the present invention in place on the boom thereof;

Figure 2 is an enlarged sectional elevation taken on line 2-2 of Figure 1;

Figure 3 is anenlarged fragmentary section of a portion of the device of Figure 1, taken on line 2-2of Figure 1; v

Figure .4 is a section taken on line i4 ofFigure 2;,

Figure 5 is a section taken on line 5-5 of Fi ure.2; j I 4 Figure 6 is a fragmentary elevation of a portion of the device of Figure 2 in one condition of operation; and, v Figure '7 is a view similar to Figure 6 of the device in another condition of operation. 7

The device has been shown in Figure 1 as applied to a crane having a boom B and supporting a lifting electromagnet' M for handling magnetic materials. It is to be understood, of course, that the device is equally applicable to other forms of lifting or hoisting machines.

In order to prevent the magnet M from spinning' and thus tangling the hoisting line L, a

tagline T is provided which passes over a sheave S attached to the boomand is maintained under suitable tension by the device-with which the present invention is primarily concerned. The power cable for operating the electromagnet M is indicated at C- In operation the reel R main tainstheftagline T under tension and thus preventsjthe magnet from twisting and at the same time protects the cable C against, undue tensioning in a manner hereinafter described.

Referring moreparticularly to Figure 2, and

the sections indicated thereon, the device em- 55 bodies flanged reel 10 for receiving the tagline This shaft I3 is rotatably mounted in a flanged bearing 4 and is' secured against outward axial movement by aa collar |5 pinned to the shaft |3. The bearing I4 is secured to a housing l6 by any'suitable means, as by bolts |1 passing through the flange of the bearing and threaded into the housing l6. This housing l6 may be secured to the boom B by U-bolts l8 and clamps l9, or in any other suitable manner. Thus the bearing l4 and housing l6 are held stationary with respect to the boom B and the reels I and l are free to rotate with the shaft 3.

Within the housing I6 ismounted a mechanism for producing a torque on the shaft 3 to produce the tension desired on the tagline T. 1'

This mechanism consists of a coiled spring 28 one end of which is held against movement under normal operation by the bearing l4'and the other end of which turns about the axis of the shaft l3 upon rotation of the shaft. This has been done in the present instance by the provision of a tube 2| which is mounted for rotation with the shaft 3 by being secured at one end to the collar and the shaft by the pin l5. The

other end of the tube 2| is mounted for rotation on the housing IS. A stub shaft 22 is secured to a plate 23 which is in turn secured to the housing l6 by welding or the'like. Secured to the tube 2| against rotation is a bushing 24. This may be done by cutting away the tube 2| and providing a projection 24' on the bushing for engaging the cutaway portion of the tube 2|. The

bushing 24 is provided witha bore rotatably engaging the stub shaft 22, thus supporting the tube 2| for rotation in the housing.

In order to transmit the torque from the spring 29 to the tube 2| and to the bearing M the spring has its ends formed with the

hooks

25 and 26, of a form shown in Figures 2, 3, 6 and 7.. The bushing 24 and the bearing |

4have projections

21 and 28 for engaging the

hooks

25 and 26 respectively. As best shown in Figures 2, 3 and 6, these projections take the form of short portions extending almost to the interior. surface of. the housing I6, said projections having one end rounded as at 21a and 23a for engaging the

hooks

25 and 26 respectively and the other ends 21?) and 28b slanting towards the ends of the housing. With this construction it can be readily seen that rotation of the tube 2| in the direction of the arrow in Figure 6 will cause the

hooks

25 and 26 to engage the ends 21a and 28a of the projections, but rotation in an opposite direction will'cause the disengagement of the hooks from the projections and will permit them to ride past the slanting or outwardly extending portions 21b and 28b thereof. This forms a ratchet and prevents the development of an unwinding torque in the spring 20 thus preserving it from destruction. The spring 20 is of such length'that upon insertion in the housing and assembly of the device, it is under some degree of compression, in order to insure that the hooks will engage the projections-upon movement-of thereel in an'unwinding direction against the tension of the spring.

Thus 'if the tagline T should break or become unfastened from the bucket, magnet, or the reel, the spinning of the reel under its inertia will not damage the spring but will merely cause the ends of the spring to become unfastened from and ride over the projections. Reverse movement on the other hand will cause the immediate engagement of the hooks on the projections and the development of a winding torque on the reels.

As was previously mentioned, when lifting magnets are used, some provision must be made to protect the power cable during operation of the hoist. As shown in Figure 2 the power cable reel is of a slightly smaller diameter than the diameter of the tagline reel l0. Thus winding of the tagline on the reel I0 is accompanied by a slightly slower winding of the power cable C on the reel I The power cable is thus never under tension except that which results from its own weight.

Provision must be made, of course, for connecting the cable electrically to a source of electric current. This has been done by the provision of a pair of insulated collector rings 30 and 3|. These collector rings are mounted on the plate I3 with insulating spacers between them and the plate I3, by

studs

33 and 34, which are suitably insulated by sleeves and washers in a well known manner. The

studs

33 and 34 may serve as connection points for the cable C, as clearly shown in Figure 3.

In order to provide a mounting for brushes 35 which cooperate with the collector rings, a plate 36 is secured to the bearing M by the bolts II. A rod 31, secured to the plate 36, forms a convenient point of attachment for the brush carrier-arms 38, which are secured to said rod for pivotal movement, and are preferably formed of insulating material, and carry brush holders 39 on their free ends. The brush holders are electrically connected to a source of power through insulated studs passing through the plate 36.

In order to protect the brush assembly from the weather and against injury, a housing 40 is secured to plate 36, and extends to near adjacency with plate |3 thus effectively enclosing the entire brush and collector. ring assembly.

In order to provide for lubrication of the spring assembly, it is desirable to fill the entire housing with grease or other lubricant. When this is done, it is necessary to provide some means for preventing the lubricant from leaking around shaft l3, to protect the brush assembly from grease. An insulating tube 4| is inserted in a bore of the collector ring assembly, and a spring 42 is inserted in the tube, surrounding the shaft l3. This spring bears against felt packing washers 43, which in turn bear against a shoulder of the shaft I3, and serve to make the space between the bearing I4 and the shaft |3 grease tight.

I claim:

1. A tagline takeup device including a support, a reel mounted for rotation thereon, a coiled spring, means connecting one end'of the coiled spring to said support and means connecting the other end of said spring to the reel to cause rotation of said reel relative to said support under the influence of said spring, at least one of said connecting means including means for releasing said spring upon rotation of thereel ahead of the spring and operativeto reconnect said spring upon rotation of the reel in the opposite direction.

2. A tagline takeup device including a support, a. reel mounted for rotation thereon, a coiled spring, said spring having a hook on at least one end thereof, means connecting one end of the coiled spring to said support and means connecting the other end of said spring to the reel to cause rotation of said reel relative to said support under the influence of said spring, at least one of said connecting means including said hook and a projection engageable thereby, said hook and projection transmitting the driving torque of the spring but disengaging upon rotation of the reel ahead of the spring and formed to reengage upon rotation of said reel in the opposite direction.

3. A tagline takeup device including a housing, a helical coiled spring having a hook at each end thereof in said housing, a cylindrical element within said coiled spring, a bushing on each end of said housing and said cylindrical element, one of said bushings being fixed against rotation in said housing and the other rotatable therein, a projection on each of said bushings extending to closely adjacent the interior surface of the housing, each projection having one portion formed to engage a hook of the spring, and the other end sloping away from the spring,

whereby rotation of the bushings relative to each other in one direction causes engagement of the hooks on the projections but rotation in the op- 5. A tagline takeup device including a housing, a reel mounted for rotation thereon, a coiled. helical spring in said housing, said spring having a hook formed on at least one end thereof, means securing said spring atone end to the reel and at the other end to the housing, said means inciuding a projection within said housing extending to closely adjacent the interior wall of the housing, said projection being formed with one end extending at a slant toward the end of the housing and at the other end formed to engage the hook of the springsaid spring being under compression, whereby rotation of the reel with respect to the housing in one direction causes engagement of the hook with the projection, but rotation in the opposite direction past the neutral point of the spring causes the hook to disengage from the projection and ride thereover.

WILLIAM RUDDOCK.