US1920989A

US1920989A - Portable crane

Info

Publication number: US1920989A
Application number: US666715A
Authority: US
Inventors: Arthur J Layhon
Original assignee: RAYMOND D HART
Current assignee: RAYMOND D HART
Priority date: 1933-04-18
Filing date: 1933-04-18
Publication date: 1933-08-08
Anticipated expiration: 1950-08-08

Description

z- 8, 1933- A. J. LAYHON l,920;989

PORTABLE CRANE Filed April 18, 1953 1'7 JrfhurJLa/z Zm.

Patented Aug. 8, 1933' PORTABLE" CRANE Arthur J; Layhon, Lowell, Mass, assignor of onehalf to Raymond D. Hart, Lowell, Mass.

Application April 18, 1933. Serial No. 666,715 8 Claims. ('01. 254-1391) This'invention relates in general. to a portable crane, and more particularly has'reference to a device of thischaracter for-use in the lifting and handling of various small but heavy objects;

Previously, in devices of this kind it has been customary to provide aboom which is either fixed with respect to the base of the crane, or else ismovable about a' pivot locatedv substantially on the base of the crane. Also, it has been customary to provide the end of this boom with a pulley adapted to receive a cable, and to extend this cable downwardly to a point on or near the base of the crane and there to provide a means -for drawing the cable downwardly over the pulley to raise the outer end of the cable and any object which might be attached thereto. Also,

' tion; the relative position and many times the the bases of such cranes have of necessity ex tended outwardly past the'outermost end of the boom thereby preventing anyobject from being either lifted from or placed on the floorwithoutv thenecessity of first swinging it so that it would not strike the base.

In the construction just described, several dif-' ficulties have been encountered, among the first v of these being that due to the usual upwardly inclined' position of the'boom, it has been. im-

possible to reach certain objects which are desired to be lifted such for'example as an automobile engine or'parts'thereof because of the fact that the other portions of the automobile would interfere with the boomin itsinclined position.

Furthermore, due to the fact that the means for drawing the cable during the hoisting operation have previously been-positioned on'the base of the crane and have consisted essentially of a reel upon which the cable is wound, considerable difficulty has been encountered due to thefact that the cable is not always 1 drawn directly in line with the. pulley and the boom. Also during. the adjustment of the boom to ahighi or low posioperation of the means for drawing the cable has been seriously affected and has served to limit the amount by which the boom'might. be adjusted." 1.

The principal object of this invention is therefore to provide a crane of the portable type within which the defects existing in prior structures will be eliminated, by whichan object" may be picked'up ordeposited on the floor directly without swinging the object or the boom for that purpose, in which the boom ispositioned in a inanner to permit it to bridge many objects which could not be bridged by the booms previously in use, and in which the means for drawing the cable during the hoisting operation is positively guided at all times so that the cable will be in direct line with the pulley at the end of the boom, and also in which the entire means for drawing the cable positioned upon the boom itself as distinguished from any other part of the crane thus avoiding the complications involved in passing the cable by pivotal joints or other connections necessary to render the boom adjust- 'spiritand scope of this invention istto be limited only by the prior art taken in connection with the accompanying claims.

Referring now more particularly to they drawing in'which like numerals indicate correspondingparts throughout: a

Figure 1 is a side View of the crane embodying this invention.

Figure 2 is a plan view of the 'sam'e.

Figure 3 is a sectional view taken along the line 3-3 of Figure l.

Figure. 4 is a sectionalview taken along the line 4-4 ofFigu re l.

Figure 5 is a sectional view taken along the line 55 of Figure 1. 7

As clearly illustrated in the drawing, this crane structure consists in general of a base .1, a substantially upright mast 2, a boom 3 extending outwardly from the mast at a point above the base and overlying the base, a cable 4 to which the article to be hoisted is, secured, and a means for moving said cable in a direction to carry out the hoisting operation. t

It willbe'seen that the base 1 consists'ingeneral of a central beam 5. having a pair of supporting arms formed by the cross beam 6extending laterally therefrom in opposite directions at one end which will be'termed its rearward end, and having a pair of supporting arms or beams '7 extending laterally therefrom at its opposite'or forward end. Thesearms 7 as illustrated not only extend laterally from the central beam 5 of the base but also extend beyond the end of this beam thereby'leaving an open space 8 adjacent the ends of thebody portion and between the two arms '7. Adjacent their outerends, each of the arms 6 and '7 is provided with casters 9 adapted to support the base 1 so that it may be rolled wherever desired. These casters 9 are so mounted that they may be pivoted about their axes 1 to permit the base to be rolledin any direction desired.

The arms 7 are provided at their rearward-ends with angularly disposed portions 11 which are rigidly secured to theopposite sides 'of the beam by means of rivets 12 or the like.

At the rear end of the beam 5 and onppposite sides thereof there are mounted a pair of upstanding brackets 13 each having a flange 14lat right angles to the beam 5. These brackets 13 are secured in place on the beam 5 by the rivet 15 or the like which passesthrough the: beam 5 and both brackets. The cross beam 6 is then secured to the rear faces of the flanges 14 by opening 37in a sliding block'38 The boom 3 is'formed essentially ofa pair of angle '5 beams having downwardly extendingflanges 22 and laterally extending flanges 23, and

a spacer bar 24 securedb etween the flanges 22 offthe angle beamsjto space them apart. The

spacer bar 24 is secured in place by two or. more rivets 25'. The spacer bar 24 is shorter than the angle beams and spaced from. either end thereof, and is of such thickness as to space the flanges 22. apart sufliciently to allow them'to" re-" ceive the upper end of the .mast 2 between them. Theyv are pivotally secured to the upper end of the mast by means such as the rivet. 26. Pivotall'ysecuredbetween the flanges 2 2 by'ajrivet 2'! at a point spaced forwardly of the mast is an adjustable bracing bar 28; The lower end or this bar is beveled off at 29 to selectively engage the notches 30 formed in the frontface of the mast 2, thus adjustably positioning the boom with respect to the remainder of the device. Forthe purpose of guiding the"portionj29initscontact with the mast and preventing it from sliding latemn out of place, a pair of plates 31 aresecured on opposite faces of the bar 28 by'rivets 32 and,

are arranged to project past the end thereof to engage the opposite'faces of {the mast. v

.Pivotally mounted on the rivet 33 between the. outerendsv of the angle beams is a pulley 34 having a peripheral groove 35for the purpose of receiving and guiding the cable 4. This cable 4 carriesa book 36' or the like at its outer end for the purpose of securing it to a lead'to'be lifted; The inner or rearward end of the'cable 4 is secured in any suitable manner within the carried on the upper surface of the boom3. This block, is formed 'with a pair of downwardly facing shoulders 39- opposing the upper. surfaces of the flanges 23 and. has a guiding tongue 40 projectinginto and guided by the slot formed between the spaced angle beams. For additionally guiding the cable 4 over the pulley 34,a combined guide and guard member '41 is secured to the flanges 23 on opposite sides of the pulleyby rivets 42 and extends over the upper edge thereof- This means of rivets or the like.

end of the boom there is a bracket 51 secured to guard is provided with a downwardly and forwardly extending portion 43 and a flared portion 44 for thepurpose of additionally guiding and guarding the cable.

The sliding block 38 is provided. with a threaded opening 45 therethrough below the opening 37 for the purpose of receiving the threaded portion 46 of the-shaft 47. Shaft 47'has a reduced portion48 at its forward end'journaled in a bracket 49 which is in turn secured to the flanges 23 by At the opposite the flanges 23 by the rivets 52 and having a bearing for journalling the shaft 4'7. The shaft is prevented from forward endwise movement by virtue of the threaded portion thereof which is larger than the reduced bearing portion 48. It is prevented from rearward endwise movement by the sleeve 53 secured to shaft 4'7 by means such as key 54. v

The rearward end of the shaft 46 is extended beyond the bracket 51 and bent to form a crank 55 by which the shaftmay be rotated to cause the 'block38 to slide back and forth in the slot between the angle beams and the hook 36 to move upward or downward as desired.

From the above description, it will be seen that a device has been provided for carrying out all of the objects of this invention, the space 8 between the arms 7 being directly below the pulley T 34 and permitting objects to be raised from or lowered to the floor between these arms without the necessity of swinging either the object or the boom to avoid the base of the crane. At the same time, means has been provided for positively guiding the cable 4 and maintaining it in alignment with thepulley 34 at all times, said means being sopositively guided by virtue of its engagement withthe slot between the angle beams and with shaft .46 that there will be no possibility of its failing in its function. At the same time, a means has been mounted entirely upon the boom 3 for raising or lowering thecable, this means .being such that it will not be interfered with by any adjustment of the. boom nor in any manner changed in its operation thereby. ..The entire de vice-is'simple and practical and of verysturdy construction. v p p .It is pointed outthat the position of the boom is adjustable to anydesired angle by virtue of 1 the adjustable brace 28.. Also it is notable that the entire device'of this invention may be readily collapsed forstorage or shipping purposes by merely removing the single bolt 17 soas to allow the mast 2 to pivot about the

rivets

20 and 21 and lie flat againstthe'base. The boom 3 may likewise be pivoted about the rivet 26 to lie closely adjacent the'under side of the base. As will be readily seen; this allows'the machine to be folded or. collapsed into'a much more convenient form for storing or shipping. I

It is to-be understood of course that various changes and modifications may be made in the details of constructionand design of this invention as set forth in the above description without departing from the spirit or scope of the invention as defined in-the appended claims.

What I claim is-'- .iSO

1. In a portable cranefan elongated base, cas- V ters for supporting said base, a substantially up- 1 right mast at one'end of said base, a brace extending between said 'base and said mast for maintaining it in upright position with respect to said'base, a boom extending from said mast in a direction to overlie saidbase, said boom pivotally axis, an adjustable brace extending between said,

mast and said boom to adjustably position said boom with respect to said mast and to prevent it from swinging downwardly about its pivot, said boom being bifurcated at its free end, a pulley mounted in said bifurcation, acable passing over said pulley and having one of its ends extending downwardly from said pulley and the other along the upper surface of said boom, a block secured to the last mentioned end of said cable, guide means on said block and said boom slidably mounting said block on said boom, and manually operated screw means for sliding said block outwardly and inwardly along said boom to lower and raise the downwardly extending portion of the cable, said base being bifurcated at aposition below the free end of said boom to allow articles suspended by said cable'to be lowered past said pulley mounted on the free end of said boom and positioned directly above the aforementioned opening between the supporting arms of the base,

said pulley being adapted to receive a cable, a slot'in said boom, a block adapted to receive one end of such cable and having a portion slidable within said slot, and screw means onsaid boom for sliding said block forwardly and rearwardly in said slot.

3. In a portable crane, a base comprising an elongated body portion and laterally extending supporting arms at the opposite ends thereof, caster means adjacent the end of each arm for supporting said base, the arms at one end of'sai d elongated body portion extending forwardly be yond the remainder of 'saidbodyportion to provide an opening therebetween, a substantially upright mast at the other end of said base,'a

boom pivoted to' said mast above said base and.

overlying the base, means for adjustably' positioning said boom with respect to said mast, a

' pulley mounted on the free end of said boom and positioned directly above the aforementioned opening between the supporting arms of the base, said pulley being adapted to receive a cable, a

slot in said boom, a block adapted to receive one end of such cable and having a portion slidable within said slot, and means on said boom for sliding said block forwardly and rearwardly i said slot.

4. In a portable crane, a base comprising an elongated body portion and laterally extending supporting arms at the opposite ends thereof,

caster means adjacent the end of each arm for supporting said base, the arms at one end of said elongated body portion extending forwardly beyond the'remainder of said body portion to pro vide an opening therebetween, a substantially upright mast at the other end of said base, a boom pivoted to said mast above said base and overlying the base, means for adjustably positioning said boom with respect to said mast, a pulley mounted on the free end of said boom and positioned directly above the aforementioned opening between the supporting arms of the base, said,

pulley being adapted to receive a cable, and means on said boom for receiving such cable and drawing it upwardly over said pulley.

5. In a crane, a base having a forward and a rearward end and comprising an elongated body 7 portion and laterally extending supporting arms at the opposite ends thereof, caster means adja cent the end of each arm for supporting said base, a substantially upright mast at the rearward end of said base, a boom pivoted to said mast above said base and overlying the base, means for adjustably positioning said boom with respect to said mast, a pulley mounted on the free end of said boom and positioned above said base rearwardly of the caster means at the forward end of the base, said pulley being adapted to receive a cable, and means on said boom for receiving such cable and drawing it upwardly over said pulley. I

6. In a crane, a base having a forward and a rearward end and comprising an elongated body portion and laterally extending supporting arms at the opposite ends thereof, meansadjacent the end of each arm for supporting said base, a substantially upright mast at the rearward end of said base, a boom pivoted to the mast above said base and overlying the base, means for adjustably positioning said boom with respect to said mast, a pulley mounted on the free end of the boom and positioned above said base rearwardly of the supporting means on the arms at the forward end of the base, said pulley, being adapted to. receive a cable, a slot in said boom, a block adapted to receive one end of such cable and having a portion slidable within said slot, and means on said boom-for sliding saidblock forwardly and rearwardly in said slot.

7. In a crane, a base having a forward and a rearward end and comprising an elongated body portion and laterally extending supporting arms at the opposite ends thereof, means adjacent the end of each arm for supporting said base, a

substantially upright mast at the rearward end of said base, a boom pivoted to the mast above said base and overlying the base, means for adjustably positioning said boom with respect to said mast, a pulley mounted on'the free end of theboom and positioned above said base rear wardly of the supporting means on the arms at the forward end of the base, said pulley being adapted to receive a cable, and means on said boom for receiving such cable and drawing it. i

upwardly over saidpulle 8. In a crane, a base, a substantially upright mast, means detachably securing said mast to said base adjacent one end thereof, a boom pivoted to the mast above said base and "overlying the base, hoisting means on said boom, means for adjustably positioning said boom with respect to said mast, and bracing means pivotally connecting said mast and said base to maintain said mast in upright position when said first mentioned securing means is in normal secured position and to permit said mast to fold against said base when said securing means is released.

ARTHUR J; LAYHON.