US2890905A

US2890905A - Lock for swiveled lifting hook

Info

Publication number: US2890905A
Application number: US529173A
Authority: US
Inventors: Raymond O Peters
Original assignee: United States Steel Corp
Current assignee: United States Steel Corp
Priority date: 1955-08-18
Filing date: 1955-08-18
Publication date: 1959-06-16
Anticipated expiration: 1976-06-16
Also published as: GB795909A; FR1155763A

Description

June 16, 1959 R. O. PETERS LOCK FOR SWIVEL-ED LIFTING HOOK Filed Aug. 18, 1955 l/EN TOR. RAYMOND 0. PE TEES,

his Afforhgy.

United States Patent O Raymond 0. Peters, Clairton, Pa., assignor to United 6 States Steel Gorporation, a corporation of New Jersey Application AugustlS, 1955, Serial No. 529,173 *4 Claims. '(Cl. 294- 78) The present invention relates to lift cranes and more particularly to a device for restricting the swiveling movement of a lift crane hook. T

1 Frequently, electromagnets are attached to cranehooks.

to. facilitate the handlingof material such as coils of steel, steel scrap in sheet and bundle form, etc. :The

electromagnet is usually provided with a lifting eye whereby it may be easily and quickly installed or removed from the hook sothat the versatility of the crane is not affected.

d When attached-to a crane hook, the electromagnet is powered by means of anelectric cable carried by the crane. "The'cable is wound on a reelwhich is arranged to wind and unwind at speeds compatible with the vertical travel of the crane hook. The lower end of the cable is usually fitted with a female electric contact plug which is ordinarily anchored on the hook block above the hook. The electromagnet itself is provided with a short length of electric cable which has a male electric contact plug fitted on its free end. The plugs are connected when the electromagnet is attached to the hook to supply electrical current to the magnet.

Prior to the present invention considerable difiiculty was encountered in maintaining an uninterrupted flow of current to the electromagnet during operation of the crane. This difiiculty arose mainly because the crane hook was free swiveling and caused the cable to twist about itself or the crane block which caused the connecting plugs to part or the cable itself to become damaged or broken. This not only necessitated frequent repairs and replacements of the cable but also created a safety hazard for workmen on the floor under the crane. Free swiveling of the hook is usually desired when it is used without an electromagnet so that it can be manipulated by a floor man to engage lifts or loads from locations which are not freely accessible.

I propose to eliminate the foregoing disadvantages by providing a locking device for locking the hook of a lift crane in non-swiveling position when it is used with an electromagnet attached.

It is, accordingly, an object of my invention to provide a crane hook lock which includes a locking plate having a bifurcated edge pivotally attached to the cross beam of a crane hook block with its bifurcated edge depending therefrom to engage the crane hook.

It is a further object of my invention to provide a locking plate pivotally carried by brackets attached to the cross beam of a crane hook block which is adapted to be placed in one position where it will engage the crane hook and restrain swiveling movement thereof and in another position where it will be carried by the brackets out of engagement with the hook so as to permit free swiveling thereof.

These and other objects will become more apparent after referring to the following specification and attached drawings in which:

Figure 1 is a side elevational view; and

Figure 2 is an end view looking toward the left of Figure 1. a f

Referring more particularly to the drawings reference numeral 2 designates thehook block of an overhead lift crane having the device of the invention mounted thereon. The hook block 2 is provided with a transverse cross beam 4extending between the side plates 6 thereof. 1 A hook 8 is mounted for free swiveling movement in the center of the cross beam 4 as at 10 by means of a bolt 12 and washer 14 in the conventional manner.

The structure just described is conventional and is not claimed as part of the invention the details of which will now be described;

Reference numeral 16 designates a base plate vertically disposed on one side ofthe cross beam 4 by means of a pair'of tightly fitting spaced

metal straps

18 and 20.

Straps

18 and 20 are connected with the back surface of the plate 16 by welding orother'wise and extend around the cross beam 4 on each side of the bolt 12.

2A Qpair oflaterally' spaced brackets 22 are attached aswby welding or otherwise on the front surfaceof the plate 16 adjacent its side edgesu If desired the brackets 22 maybe attached directly onto'the side surface of thef cross beam. However, I'prefe'r to mount themas shown in order to eliminate any'possibility of weakening the 4:11; cross lieamby making welds thereon. Each of the brackets 22 is'provided withan L-shaped-slot 24i *Th long leg of each of the slots extends in a horizontal plane substantially normal to the front surface of the plate 16 while the short legs extend downwardly from the ends of the long legs adjacent the plate 16. The ends of the slots 24 remote from the plate 16 are closed by means of a strip 26 welded thereacross. The short legs of the slots 24 terminate short of the bottom of each bracket and are therefore also closed at their bottom ends.

A locking plate 28 having a bifurcated edge 30 and laterally projecting lugs 32 adjacent the edge remote from the bifurcated edge is pivotally mounted on the brackets by means of hanging the lugs 32 in the short legs of the slots 24.

The plate 28 is mounted in locking position by fitting the lugs 32 into slots 24 so that the bifurcated edge 30 depends from the brackets and engages the body of the hook 8 opposite its point. The diameter of the hook 8 which extends from its point 34 to its outer edge 36 is greater than the width of cross beam 4, so that the body portion of the hook projects beyond the outer edge of the beam 4 where it may be engaged by the plate 28. When the plate 28 is in engagement with the hook 8, the hook is restricted movement and is no longer free swiveling.

When it is desired to use the crane with the hook in free swiveling or unlocked position the plate 28 may be pivoted upwardly about degrees from the hook and pulled forward so that the lugs 32 are fitted in the outer ends of the long leg of the slots 24 as shown in dotted lines in Figure 1. The plate 28 will remain in this position out of engagement with the hook 8 since the width of the lugs 32 from the top and bottom are greater than the opening of the slot 24 at the outer ends of the long legs thereof. The plate 28 may also be placed in disengaged or unlocked position by pivoting it upwardly about degrees, as shown by broken lines in Figure 1, with the lugs 32 remaining confined within the short legs of the slots 24.

While one embodiment of my invention has been shown and described, it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

I claim: 7

1. In a hook block including a cross-beam having a,

longitudinal axis and a hook having a hook portion and 1 afiixed to one side of said cross-beam, a plate havingaa,

iiDEQ Q :O 'F I #idgs ia ld being=0f :suflicientzlength -.t a a said -'h Q 'iP E n andnnreans :pivotally :moun-ting saidplate on, 1 said brackets about ;a pivot-parallel :to .said

longitudinal of said cross-1bearn, said plate ibeing pivotal from a loeking position wherein vsaid bifurcated edge engages said hook portionrtotanon-lockingposition wherein ,said bifurcated edge is remote=from said hook portion. p v

2. 1m a-hook block inolndinga 'vcross-beatn' having a longitudinal axis land a hook having a :hooksportion and a shank swivelly mounted on said cross-beam with the shankiaxis normal to the longitudinal axis of said vcrossbeam, the improvement therewith of an anti-swivel lock Which comprises a pair of longitudinally spaced -brackets aifixed to one side of-said cross-beam, said brackets each having an -L-shape slot therein, the long leg of each of said slots extending in a horizontal-planesubstantially normal to the longitudinal of ,said beam and the short leg of each of said slots extending downwardly from the end of said long leg adjacent said beam, said slot having a widened, Portion at the junction of. the .two legs thereof, a locking plate having a bifurcated edge and a lug projecting laterally from each side of said plate adjacent the edge;thereof remote from saidbifurcated edge, the thickness of each of said logs from the 4 7 bottom to the top thereof being greater than the width of the long leg of .eachof said slots adjacent .the end thereof remote from said beam, said plate being mounted on said brackets about a pivot parallel to said longitudinal axis of said cross-beam for movement between a first position wherein said lugs are disposed in the short legs of said slots and said bifurcated edge depends from said brackets and engages said hook portion to restrain the swiveling thereof and a second position wherein said lugs are confined in the long legs of said slots and said plate extends substantiallygnormal to .said rbeamand out of engagement with said hook portionto permit free swiveling of the hook.

3. In a free swiveling crane "hook theimprovement therewith as defined in claimZ in which said locking plate is pivotal on its lugs within the short legs of said slots substantially 180 degrees counterclockwise away from said hook.

.4. 1111.21 free .swivelingscrane hook the t-improv ement therewith asxdefined by .claim '2.-inoluding a base plate said base plate and a central portion extending around said beam to secure said base plateonsaid' beam.

References Cited inthe file of this patent UNITED STATES PATENTS