US2552698A - Portable hoist and load transporting device - Google Patents

Description

15, 1951 R. A. WALLACE 2,552,393

PORTABLE HOIST AND LOAD TRANSPORTING DEVICE Filed May 16, 1947 3 Sheets-Sheet 1' "M o my 15, 1951 re. A. WALLACE f2,552,69&

PORTABLE HOIST AND LOAD TRANSPORTING DEVICE Filed May 16, 1947 15'%00t8-5h69t 2 R. A. WALLACE PORTABLE HOIST AND LOAD TRANSPORTING names:

May 15, 1951 3 Shins-Sheet 3 Filed May 16, 1947 NEW llFiV////////.1II//A INVENTOR. flaw/0554. [IQ/lace w kn 9v Qw Wh n.

Patented May 15, 1951 UNITED STATES; PATENT OFFICE PORTABLE HOIST AND LOAD TRANSPORTIN G DEVICE Richard A. Wallace, Hagerstown, Md.

Application May 16, 1947, Serial No. 748,457

1.2 Claims.

bodying a base of channeliron construction, a

mast of I-beam constructionrisingfrom the'base, and a boom of channel" iron construction supported by the mast whereby the crane is relatively light in weight and thus easily: transported to and from different operative positions, while onthe other hand; crane is strong and capableof withstandingzsubstantiel weight in the lifting operations thereof.

A still further object of" the invention is the provision of a. portable crane" embodying a caster supported base, a mastextending vertically from one end of the base and a boom slidably supported at one end thereof on the mast for vertical adjustment thereon to different operative positions upwardly from. a; point. adjacent the base, awindlass supported by the mast, and a cable extending from a drum on the Windlass successively over pulleys on the, mast and. boom and supporting a hook at its: free end depending beneath the free end of the:- boom, the base being of substantially greater. length than the boom for, positioning of the free end portion thereof beneath an object to be lifted and handled by the boom.

A still further object of the invention. is the provision of a portable crane embodying an elongated caster supported base and awindlass operated lifting hook disposed above the base in spaced relation to anend thereof, and the base being provided with a removable support beneath the hook whereby an object may be lifted by the hook and loweredionto the removable sup,- port, and the object: then conveyedtoa desired point through movement of the caster'supported base.

A still further object of-the invention is the provision of a portable crane including a base, a mast, and a boom slidable on the mast and. supported thereby at desired predetermined positions above the base, a Windlass. operated cable extending from. the mast along the boom to depend from the free end, thereof formovement relative thereto, and the'cable being providedwith a hook. on its free end adapted; to engage the boom to arrest relative movement between the cable and boom whereby theboomwill move with the cable uponfurther operation of the windlass.

2 A still further. object, of the invention isthe provision of a portable craneincluding a base, a mast, and a boomslidably supported on the mast, a2 Windlass operated. cable extending along'the boom and movable relatively thereto, and clamp means for selectively locking the cable to the boom for-movement of the boom along the mast upon movement of the cable.

A: still further: object of the invention is the provision of a portable crane including a base, a mast extending vertically from the base and a. boom having one end thereof slidably supported on the mast, wherein provisionis: made forselectively. holding the boom in successive vertical adjusted positions on the mast and: for permitting the boom todescend on the mast, and wherein the boom isfree to rise on themast,

either when engaged by the cable hook or when" thecable is locked by-the: clamp means.

Other: objects and advantages of the invention will: become apparent, in the course of the following disclosure:

Fig. l is aside elevational view of the improved crane, with theboomthereof in an in termediate position on thezmastand' the Windlass operated v cable depending fully from'the; free end of the boom; an upper extreme position of the boom being illustrated in dot-and-dash lines;

Fig. 2 is an enlarged section in the plane of line 2-4, Fig. 1;

Fig; 3lisa rear elevational view of the crane of. Fig. 1;

Fig. 4 is a front elevational view of the crane with the parts in thefull-line position of Fig. 1;

Fig; 5' is'an enlarged vertical sectional. view in the plane of line 55, Fig. 1;

Fig; 6 is a top plan view ofthe crane showing the supporting base and relation of the boom thereto;

Fig; '7 is a side; elevational view on a substantially enlarged scale, of a combined cable clamp and boom retaining means forming one of the structural features of my improved crane, the

view being partially in section;

Fig; 8. is a, right hand end elevational. of the structure as illustrated in Fig; 7' and showing a section of the boom with which it is operatively associated.

Referring nowin detail to the-drawings, and

structure while the boom I2 is slidably supported? on the mast for vertical movement relative to the base.

An important feature of the invention is in the structures of the base,,mast and boom, which constitute the major elements of thecrane, so that the device will be relatively-light in. weight.

while possessing maximum strength. Accordingly, the base I and boom l2 are formed of joined channel sections whereas the mast II is an I-section beaml5. The base lllcomprises a pair of channel sections 13 which in the side elevational view are shown to taper from the mast toward the free ends thereof. The base sections" l3 have their wider flanged end portions curved upwardly as at I4, whose free edges engage beneath a side flange of the I-beam |,5 which is cut away at the base of the beam for assembly of the the-like in a manner later referred to. The rigid base and mast structure is readily transportable in the'provision. of a caster H) at the front end of each' base or frame section l3. A third caster has a swivel connection 2| at the lower bev elled end of the beam l5 which is provided with a' flange 22 in continuation of the'outer side flange of the beam thereby providing proper support for the caster 20. a The boom I2 comprises a pair of channel sec-' tions 24 which taper toward their free ends in both side and top views, and these sections as well as the base sections l3 have theiropposing channels facing outwardly of the vertical center plane of the crane. The channel sections 24 have their base walls 25 in uniform spaced relation, as is clearly indicated in' Figs. 4 and 6, for a purpose later to appear. The sections 24 are of substantial widthadjacent the mast beam l5, and such sections'curve'downwardly as at 26 in the provision of substantial depth of the sections adjacent'themas't' beam l5. s

The twosections 24 are of substantially greater combined width than the beam l5 and they are outwardly recessed from the center vertical plane thereof to provide walls 21 laterally displaced from thewalls 25 for slidable engagement with the edges of the side flanges of the mast beam l5. Theforward flange of the beam is slidably engaged by the forward end of the recess; and thefreai" ends of the sections 24 are turned inwardly as at 28 for slidable engagement with the rear flange of the beam IS.

The boom sections 24 are preferably interconnected by suitable means suchas plates 30 welded to'their upper and lower flanges whereby to hold the-sections as a rigid boom unit. Thus, it will be seen that the boom 12 by the provision of the constructionof'its rearenlarged end as above described is "vertically slidably supported on the mast'beam I5.

A Windlass 3| is rigidly supported on the rear flange-of the mast beam l5, and which comprises anopen' top box-like support 32 connected by block 33 tothe beam l5 and which block is disposed between the guide flanges 28 of the boom sections 24. Rotatably supported in the support 32 isa cable drum 34 which is driven by a worm gear 3'5'flxed on the drumshaft 35' and a worm 36 carried by shaft 36 meshes with the wormgear 35.: A worm operating handle 31 is provided with' seve'ral rectangular apertures 3'! for selective engagement with asquared end of shaft 36' for provision of suitable variable torques.

A cable C having a substantial length thereof wound on drum 34 extends upwardly along the rear flange of the mast beam |5 and thence over horizontally spaced pulleys 38 and 39 rotatably supported in a frame 40 rigidly secured to the upper end of the mast beam l5 by means of the lap joint construction 40. The cable continues from pulley 39 downwardly along the front flange of beam l5 and thence under a pulley 4| rotatably supported between the base walls 25 of sections '24, and the cable continues from the pulley 4| between the spaced walls 25 and thence extends over a pulley 42 rotatably supported between the walls 25 at the free ends of the boom sections 24.

A plate 43 is secured to? the lower flanges of the sections 24 andis provided with an aperture through which the cableqC. freely extends but' which. precludes passage of the swivel hook 44 connected to the free endo-f the cable; The plate 43 cooperates with plates 30 in maintaining the boom sections 24 rigidly interconnected. 'In order.

to preclude binding between the boom IZ'andv the mast H. a pair of upper rollers 45 and a like pair of lower rollers '46 are/rotatably supported by the walls 21 of sections-"24, the first pair of rollers engaging the front flange of the beam [5- and the second pair of rollers engaging the 'rear flange of the beam. From the foregoing it will be observed that the mast provides laterally spaced slideways engaged one end of the boom.

The invention comprises means for holding the boom l2 against downward movement on themast. ||gandfor holding the cable C against movement relative to the boom. Such means, in

a preferred embodiment thereof, comprises an elongated block 48 disposed between and suitably secured to the wa1ls'25 of the boom sections 24 and such block is provided with opposed wedge walls 49. Also disposed between the walls 25 and suitably secured thereto is a second block 513 provided with a cylindrical recess 5| whose open end is disposed adjacent 'a suitable plate 52,'secured' to one of the side flanges of the I-beam I5 in vertical position and having'a plurality of suitably spaced circular apertures 53 corresponding in diameter to that of the recess 5|.

The cable C extends through the block 48 and between a pair ofclamping jaws 54 which have ,wedge 'walls 55 cooperating with the walls 49.

The jaws 54 extend outwardly of the block 43 and have floating pivotal'connections 56 with a pair of level" arms '51 whose upper ends are piv-' otally'connected at 58 to the walls 25.

. The lower endso'f'le'ver arms '51 are pivotally connected at 59 to an end of a link 50 havinga' right angular extension 6| on its opposite end. 7 A

second and similar link 62 is provided with a right angular end extension63 facing oppositelyto the extension 6|, the links being in laterally spaced relation at the region of said extensions.

The opposite end of the link 62 is provided with Y a lengthwise slot 64 in whichis disposed a pivot pin 65 carried by one end of a stem 66 which extends through an aperture 61 at the base of the recess 5| and is provided with a latch bolt 67 disposed within the block recess 5| which is provided with an end adjacent plat 52 upwardly and inwardly bevelled, as indicated at 68. A coil spring 69 is disposed within the recess 5| in encircling relation to the stem 66 with its opposed ends engaging the bottom of recess 5| and the adjacent end of the latch bolt 61.

'An'ope'rating handle 69 includes an elongated end member 10 disposed between links 60, 62 and" by rollers supported bylatch bolt 6! is withdrawn from anaperture 53- in the plate 52-. These operations are efiectedi by movement of handle 69 towardthe free endof the boom and in which movement,.member l llmoves' links 60, 62 slightly toward each other inalengthwise direction. The link 60 pivots arms. 51 ina direction to force jaws 54 into clamping engage-= ment with the cable C, the link 62 withdrawing the latch bolt 61 from within one of. theaper tures 53.

Upon swinging the handle 59 toward the mast ll into the position indicated by dotted lines in Fig. 7 and in full lines in Fig. l, the cable C is released by the jaws 54 and the latch bolt fi'l moves into contact with plate 52 for engagement with an aperture 53 when the block recess becomes aligned therewith. The slot 64 in link 62 providesfor movement of latch bolt 61 through camming action of the bevelled end 68 with theedge of an aperture 53 against the action of. spring 69 when the cable is unclamped and when the hook 44 engages the plate 43 for raising of the boom. It is to be noted that the pivots H are disposed on opposite sides of a line' arall'el to the axis of stem 66 and extending through the pivot ll whereby the spring 69 maintains the cable in clamped position through a toggle action;

From the foregoing, it will be apparent that the improved crane is relatively light inweight, thereby adapting it to ready movement from place to place by pushing the same through han dles 13 secured toor unitary with the Windlass support 32, the casters I9 and providing for either straight line or angular movement of the crane along a floor. Notwithstanding suchlightness, the crane is strong and capable of withstanding heavy loads, as well" as rugged use.

The base IB is preferably provided with a removable panfor supporting a motor or the like for transportation from one point-to another, and such pan is disposed immediately below the cable hook 44, as will be apparent-in- Fig. 6; The pan preferably comprisesa pair of L-sec'tions 14=hav'-- ing a block l5 carried thereby, theblock being provided with a recess defined by the opposed angular walls It. The sections 14 are-provided with hooks T! on their opposite ends-for'engagement over the base sections 1-8 and: the-rearm'ost hooks are preferably provided with slots 18 for removably receiving pins 19 on sections 18, which pins restrain movement of the pan down the sloped'forward end of the base.

In operation of the crane, it maybe positioned with the base H] which is substantially longer than the boom l2 disposed with its forepart beneath a motor or other object to be raised, with. orwithout the pan in position. The boom is positioned at the most convenient altitude on the mast and so retained by the latch bolt 61. Should it be desired to raise the boom to-a higher position on the mast, the knob 12. is graspedv and the handle 69'moved to the fullline position of Fig. 7 wherein the cable is clamped to. the boom and the latch bolt 61 retracted. Upon rotation of the Windlass worm 36 and consequent rotation of the drum34 the boom will be raised by the cableC and upon release of the cable'by moving handle 69 in the opposite direction thelatch bolt 61 will snap into the next adjacent aperture 53 below the axis of the latch bolt.

While the latch bolt 61 will permit upward: movement of the boom in either position of the handle 69, it is necessary that it be withdrawn as in Fig. 7 when it is desired to lower the boom. With the boom positioned in a desirable position, the cable is moved by Windlass 3| to spring the hook 44 into adjacency to the object to belifted. Upon engagement of the objectby the hook the Windlass is operated and the cable moved with aresulting lifting of the object. Should it be desired to lift the object to a height greater than that at which the boom may be positioned, the hook 44 will engage the plate 43 and lift the boom with the object, the latch bolt 61 riding into and out of the successive apertures 53 against the action of spring 69. It is to be noted at this point that the cooperating worm gear 35 and worm 36, while providing for movement of the cable upon actuating of the handle 31, act as a lock against reverse movement of the gear and worm whereby a load being lifted will be retained thereby.

While I. have disclosed my invention in accordance with a single specific structural embodiment thereof, it is to be understood that changes may be made which fairly fall within the scope of the appended claims.

What I claim is: 1. A portable lifting devicecomprising a caster supported base, a mast upstanding" from the base, said mast having laterally spaced slideways extending vertically from the base, a horizontal boom having a slide at one end thereof engaging the spaced slideways of the mast, retractible latch means between the mast and boom operative to hold the latter against downward movement while permitting upward movement thereof, a windlassfixed to said mast, a pulley adjacent the upper end of the mast, a pair of pulleys mounted on the boom, one adjacent the slide and the other adjacent the free end of the boom, 2. cable extending from the Windlass over' the said respective pulleys and depending from the free end of the boom, interlocking means between the boom and the cable adjacent the inner end of the boom, and connecting means at the free end of the cable for engagement with the load, whereby a load may be moved to and from the boom or the boom moved to and from the base by the cable.

i A portable hoist and load transporting device comprising a caster supported base having a load support, a mast upstanding from the base, a boom slidably mounted on the mast and extending from one side thereof over the base for movements relative thereto, manually releasable latch means between the mastand boom for restraining downward movement of the boom while permitting upward movement thereof, a Windlass mounted on the opposite side of the mast, a pulley adjacent the upper end. of. the mast, a pair of pulleys mounted on the boom, one adjacent the inner andone adjacent the outer end thereof, a cable extendinglfrom the Windlass over the said respective pulleys and depending from the outer end of the boom, and manually operable clamp means supported by the boom for re straining movement of the cable relative to the pulleys on the boom.

, 3. A portable crane'comprising a verticall'y' and a boom formed of a pair of channel sections. I

with corresponding ends thereof slidably supported on the mast.

4. A portable crane according to claim 3 wherein the boom channel sections at said correspond ing ends are recessed in the provision of a guide slidably receiving the side flanges of the I-beam section.

5. A portable crane according to claim '3 wherein the base walls of the boom sections are in spaced relation providing a channel therebetweenfa windlass supported onthe rear flange of the I-beam section, a pulley rotatably supported on the upper end of the I-beam section, a pair of pulleys rotatably supported by said basewalls between the boom sections, and a cableextending from the windlass and successively engaging said; pulleys and extending from one of said pairof pulleys to a position beneath the free end of the boom and having a hook, on the free end thereof.

6,.- A portable crane according to claim 3 wherein said base extends substantially beyond said-boom, and a removable load support carried between and by said base channel sections beneath the free end of the boom. 7

7. A portable crane comprising a'caster supported base, a mast of I-beam formation extending upwardly from one end ofthe base with its flanges fore and aft of the crane, a boom slidably supported by the mast and including opposed walls'slidably engaged with opposed edges of the flanges of the I-beam and in spaced relation to the web thereof, the boom including spaced walls defining a channel therebetween extending from the mast to the free end of the boom, a windlass supported by the aft flange of the I-beam section, a pulley supported by the upper end of the mast, a pair of pulleys supported by said walls and disposed in said channel, a cable extending from said windlass and extending successively over said pulleys with the free end'thereof depending from the free end of the boom, releasable latch means for retaining the boom in selected adjusted positions on the mast, and clamp means for locking the cableto the boom.

8. The structure according to claim 7 wherein said latch means and cable clamp means are disposed in said channel, and a handle'operatively connected to the latch means and cable clamp: means accessible beneath the boomand opera-- tive to simultaneously actuate both of said means.

9, A portable crane comprising a caster supported base, a mast rising from one end of the base, and a boom disposed above the base and having one end thereof slidably engaged with the mast, a windlass supported on the mast, a

pulley at the upper'end of the mast, a pair of pulleys supported by the boom, a cable extending from the windlass over the respective pulleysand depending from'the outer end of the boom, a plate connected with the mast and having a series of vertically spaced apertures therein, the boom including a pair of spaced sections defining a channel therebetween, a pair of blocks sup, ported in said channel with the cable extending through one of theblocks, normally retractible clamping jaws disposed in said onev of the blocks, a' spring urged latch bolt slidably disposed in'th'e: other of "said blocks for normal engagement within one of said apertures, a handle pivotally' connected to'said boomsections and depending from beneath the-boom, and operative connections between the handle and the clamping'jaws and the latch bolt for simultaneously moving the jaws to cable clamping position and for retracting the latch bolt from engagement with the plate aperture. 7

' 10. A portable crane according to claim 9 wherein said connections comprise a pair of links pivotally connected to an elongated member on the handle with the pivotal connections on opposite sides of the pivotal connection of the'han and an actuating handle provided with spaced apertures for selectively receiving the second named shaft. I I

12. A derrick [comprising a wheeled chassis having a winding .drum mounted thereon; a

mast supported bysaid chassis and extending upwardly therefrom; a pulley mounted on the upper end of said mast; a boom slidably mounted on said mast and extending substantially; horizontally therefrom at a level beneath said pulley; means for-securing said boom against sliding movement relative to said mast at a selected vertical position of the boom; a second pulley mounted on said boom at one end thereof.

adjacent to said mast; a third pulley mounted on said boom at the other end thereof; a cable extending from said winding drum and engaging said pulleys in the order stated; hoisting means at the end of the cable beyond said third pulley; and engaging means on the boom adapted to engage said hoisting means to prevent movement of said cable relatively to said boom, whereby said boom may be moved to a desired vertical position with respect to said mast by said cable and winding drum when said-hoisting means is engaged with said engaging means on the boom; and the boom is released from the mast, and the' hoisting -means, cable and winding drum may be used to hoist objects when the boom is secured against sliding movement..

RICHARD A. WALLACE,

REFERENCES CITED The following references are of record in the file of this patent;

UNITED STATES PATENTS Number Name Date 1,103,823 Padgett et a1. July 14, 1914 1,428,887 I-Iescock Sept. 12, 1922' 1,551,132 Butler Aug. 25, 1925 1,563,768" Mallinckrodt Dec. 1, 1925 2, 88,793 Delano -11.. July 7, 1942 2,315,873 Richards Apr. 6, 1943 2,329,008 Smith. Sept. 7, 1943 2,344,134 Davis Mar. 14, 1944 2,433,921 Nelson -Janz6, 1948

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