US2726781A - Lift truck attachment - Google Patents

Description

Dec. 13, 1955 H. H. STANLEY 2,726,781

LIFT TRUCK ATTACHMENT Filed March 2, 1953 2 Sheets-Sheet l fmxewfor f/am/c/ Zi ffim/gg f uq Dec. 13, 1955 H. H. STANLEY 2,726,731

LIFT TRUCK ATTACHMENT Filed March 2, 1955 2 Sheets-Sheet 2 f a 2 02 flaw/0 352/ gym AM United States Patent 6 LmT TRUCK ATTACHMENT Harold H. Stanley, Hales Corner, Wis, assignor to General Electric Company, a corporation of New York Application March 2, 1953, Serial No. 339,627

8 Claims. (Cl. 214654) This invention relates to material handling equipment, and in particular, to a lift-truck attachment by means of which crates, drum-pack cartons and the like may be handled with equal facility.

In the manufacturing of major domestic appliances, such as clothes washing and dishwashing machines, water heaters and the like, it is not unusual to conduct the manufacture in the same plant. Because of differences in dimension, weight, and other factors, some types of appliances may be packed for shipment in wire-bound crates, whereas others may be packed in what is known as drumpack cartons. The wire-bound crates have slatted side walls, whereas the drum-pack carton most frequently embodies solid corrugated cardboard walls and cover and base portions having strong marginal structures which engage the carton walls in interlocking relationship. Insofar as I am aware, before my invention there was no single lift-truck attachment which would adapt a truck for handling both types of packages, and it was necessary to have a specialized lift-truck for each type. Such a situation was, obviously, inefi'icient when mixed shipments were to be handled.

It is therefore a general object of my invention to provide a lift-truck elevator which will automatically adapt itself both to crates and drum-pack cartons.

It is another object of my invention to provide a lifttruck attachment which utilizes a novel combination of relatively narrow hook members insertable between the slats of a crate and relatively broad hook members arranged to pass between the cover and side wall portions of a drum-pack carton.

It is a further object of my invention to provide a lifttruck elevator having mutually cooperating sets of hook members for respectively handling drum-pack cartons and crates, and in which one set of hook members supports the second set when the latter is engaged in lifting crates or. similar slatted containers.

I Other features and advantages will be apparent from the following description of a presently preferred embodiment of the invention, read in connection with the accompanying drawings, in which:

Fig. l is a side elevation of a lifting truck equipped with an embodiment of my invention;

Figs. 2 and 3 are upper-portion views of a drum-pack carton to illustrate the relationship of the cover and side walls thereof;

' Fig. 4 is a front elevation of the invention;

Fig. 5 is a side elevation of the invention in section on lines 55 of Fig. 4, showing the manner of engagement of the lifting hooks with a carton; and

Fig. 6 is a similar view showing operation of the cratelifting hooks.

A con entional lift-truck T has the usual elevator mechanism E arranged to be raised and lowered along the upstanding guide rails R by any conventional means (not shown) under control of an operator.

The present invention includes the lifting carriage 1 arranged for securement to the truck elevator mechanism. In the specific embodiment illustrated, the lifting carriage comprises a rigid framework having the spaced substantially vertical side rails 2 and rearwardly extending upper and lower members 3 which are secured by any suitable means to the elevator mechanism. A transversely extending lower structural member (Fig. 4) is welded or otherwise rigidly secured to the lower portions of rails 2 and preferably is structurally reinforced with respect to said rails by the welded gusset plates 5. The rails 2 and structural member 4 may be of any appropriate structural shape; the illustrated channel section of rails 2 and barlike nature of member 4 is not intended to be restrictive. At each end of the member 4, there extends a short shaft 6 which rotatably receives a, shoe 7. Each shoe includes a flat working face 8 preferably rearwardly curved at its upper edge as shown; and the inboard web 9 of each shoe has an arcuate slot 10 within which freely extends a pin 11 anchored appropriately to the member 4. It is understood that the shoes are freely rotatable about their shafts within the limits permitted by the lengh of slots 10.

Suitably above the cross member 4 is a second transversely extending structural member 12 fixed securely to the rails 2. The member 12 carries the lifting device presently described.

Considering first the construction of a typical drumpack carton, a carton X, Figs. 2, 3 and 5, is usually a rigid corrugated cardboard structure having the cover and base portions X1 and X2 in an interfolded relation with flanges X3 of side walls X4 as clearly appears. The top and base portions are ordinarily secured to the side walls by spaced wire staples, as is well understood. It is sometimes the practice additionally to strengthen the cover and base portion by steel strapping (not shown) extending about the four margins of the cover and base.

A typical crate Y, Fig. 5, includes upper and lower structures having frame members Y1, cover slats Y2, and spaced side slats Y3, arranged in suitable open patterns about the four sides of the crate. The respective crate elements are usually secured together by stapling or nailing and are often additionally reinforced by wire bindings (not shown). In such typical crate constructions, there are therefore open areas which will permit the entry of lifting devices for engagement with the undersides of the top frame structure elements Y1.

For use with the drum-pack cartons, I apply to the upper transverse member 12, as by welding thereto and to the rails 2, a set of plate-like lifting hooks 14 which extend angularly outwardly from the rails 2 and then upwardly in suitably spaced parallel relation therewith. The spacing between the books 14 and the rails should, of course, be somewhat greater than the multiple thickness of carton material at the juncture of the cover and side wall portions thereof. The relatively large front wall of each hook 14 is in the same vertical plane, and the top of each hook is preferably in the same horizontal plane. To facilitate entry of the top edges into the space between the carton wall and the interfolded cover and wall portions, said top edges may have an ogival formation.

For use with crates, I mount on the transverse member 12 as by pivot'rods 15 projecting from the support blocks 16 secured to said member, a plurality of relatively narrow lifting hooks 17 which freely rotate on the associated pivot rods. Each hook of this second set is biased into rotation forwardly of the rails 2 by the coil springs or equivalent 18. As best appears in Figs. 5 and 6, these hooks are substantially S-shaped. The olf-set center portions 17.1 terminate in the upwardly extending billed ends 17.2. Means are provided to limit the forward rotation of the hooks. As respects the right and left pairs position the hooks 17 for operating, but provide a base to support them when under load. specifically the outermo'sti edges? of thehooks 1'4 are stepped to provide a shoulder 14 .1 which extends beneath the offset 17.1'of 'the'hooks' to support the same. To support theo'ther hooks 17 disposed directly behindtlie plate portions of hooks 14-, said plate'portions are slotted to provide the base'walls 14.21 I It will be unders'tood'tliat the slots pro vide' for the: unimpaired withdrawal of the hooks 17 to an inoperativeposition when the lift-truck is, handling cartons ratherthan'crates; The centrally disposed hook 1'7 cooperates: with a supp'ort'pla'te 18 fixed'tot'ran'sverse bar 12 and of suitable size and shape to position its associated hook inoperative alignment with. the :other fingers ofthegroup' V p As best'shown' in Fig. 5} when the truck is to'lift cartons; the operator'maneuvers thetruck until the shoes 7 andthe hooks 14 abut the side wall of thecarton. As these elements press against the carton wall,'the shoes take a position in vertical alignment with the faces of the hooks. 'The upper edges of the hooks will at this time be below thejcover side wall. Then as the operator begins to raise the lift truck elevator, the upper edges of the hooks enter the interleaved cover elements and ultimately begin to lift the carton. The shoes hold the carton steady against any swing or twist which might tear the carton at its upper wall portion. It'will be noted that as the hooks'ldengage the side wall of thecarton, the hooks'17 will withdraw to'the rear of the hooks 14 so 1 as not to interfere with the operation of said hooks.

Whenha'ndling crates or other containers in' which the side walls have openings thru which the hooks 17 may extend; the operator maneuvers his truck until sets of said-hooks enter thru the open spaces of the crate below the upper framestructure thereof. In any areas in which the hooks may contact slats or other side wall portions,

they will yield rearwardly and will not interfere with;

the" proper alignment and securement of those hooks which haveentered the crate below the top frame'strue' m're; As" the elevtaor of the 'truck' begins to raise, the

upper ends' of the hooks will engage the crate structure an'dlift' the crate. The plate-like hooks 14will'provide a base for certain of the hooks 17, and plate 18 serves'a similar function with its associated hook. There are several'p'ossibilities as respects the operation of the' hooks-17. "The'ir bills may bite into thelower surface of the rails Y1, in which event the crate will be relatively free to swing about the hooks as a pivot. Obviously,-the 'lower portion of the crate will swing toward the rails 2 and will strike and thereafter be steadied by the shoes 7. Again, it'rnay be that one of the cross frame members Y1 will be straddled by the upper port'ion of the hooks 17 and'the face of the adjacent hook 14, as suggested-in: Fig. 6. Both sets ofho'ok's will thus coopcrate to grasp theframe members se'curely. Finally, it is-possiblefor the lift-truck to handlea'structure of such shape or arrangement that an upper railis' best engaged between the book 14 and the adjacent vertical rails 2.

The horizontally extending portion 17 .1 of the hookstrue spirit and scope of my invention.

1. Ina lift truck'having' anelevator arranged tobera 'ised'or lowered along-upstanding guide rails, theimp'rove'ment comprising a structural element fixed to said 4 elevator for movement therewith, saidelement extending transversely of said guide rails, a plurality of upwardly directed plate-like hook members fixed to said element at intervals along the length thereof, each said hook member having an elongated article engaging edge portion disposed'in a common horizontal and vertical plane forj ward of said structural element, a plurality of mutually spaced relatively narrow, upwardly directed, hook members pivotally mounted on said element rearwardly of said first-named hook members for rotation in a vertical plane, each of said sec'ond-na'med hook members having a relatively sharp article-engaging end portion, and means for biasing said second-named hook members into an operative position with the end portions thereof in a common vertical and horizontal plane forward of and' below the said article-engaging edge portion of said firstnamed hook members while permitting retraction with respect thereto. I

2. In a lift truck having an elevator arranged tobe raised or lowered along upstanding guide rails, theimprovernent comprising a structural element fixed to said elevator for movement therewith, said elementextending. transversely of said guide rails, a plurality of rigid'hook members of substantial frontal area fixed to said element at intervals along the length thereof, each said hook member having-a" substantially vertical plate-like stiucture in which the upperfedge comprises an elongated article-engaging portion disposed in a common horizontal and vertical plane forward of said structural element, a

plurality'of relatively narrow, upwardly directed, hook member's pivotally mounted on saide1ement-forrotation in a vertical plane, each of said second-named hookf members having a' relatively" sharp articleengaging end' portion; means carried by said" structural element forsupporting said second-named hook" members in anoperative position with the end portions thereof in a common vertical and horizontal plane forward of and below' the said article engaging portion of said firstnarned hook members and normally intersecting the plane of the vertical plate portions of said first-named hook members, and means for biasing'sa id secondnamed hook members into said operative position, while permit} ting retraction with respect to said first-named hook m'embersl 3. Lift truck mechanism according to claim" 2,Lin.

which certain of said' second-named hookrnembers project'through apertures insaid first n'amed hook members and are supported in operative positit jnlby a wall thereof. 4. In a" lift truck'having' an a plurality ofplate-like,hook members secured to said. structural element in spaced" relation therealong the frontal portions of'said-hook'mjembers extending vertically in a commenvertic'al'plane'forward" of said structural element and terminating in article-engaging edge portions disposed in horizontal and'yertical'alignment, a

plurality of relatively narrow, substantially S' sh'a'ped- V hook-members pivotally supported' at one end on 'said structural element rearwardly of said first-namedhook members and reaching forwardly and upwardlywithrespect thereto, spring means ass'oeiatedwith said S-shaped hook'rnembers tobias said hoek members into rotation forwardly of said first-named hook members to positionthe free end portions of said" ,S 'shape'd hook .rn'ernbers forwardly of and heneatl'i' the article-engaging edge per tions of said first-named hook members. said free end" portions slopin'g' 'arigul'arly upwardly, and' me'aiis including saidplate-like hook manners? toTs'uppTorf said' 8 sh'a'pe'd ho'ok members ip saidiforward positioii'with the.

free ends of said hook' menibers tenhinatingin" amen; engagingtips disposed in" substantially a" cornnrn hori- Zontal and vertical plane.

7 eleva'torfarrangedto be raised or lowered, thejimprov'enient comprisinga struc- 5. In a lift truck having an elevator arranged to be raised or lowered, the improvement comprising a rigid substantially rectangular-structure fixed to said elevator for movement therewith, upper and lower portions of said structure extending substantially horizontally, a plurality of plate-like hook members secured to said upper portion at spaced intervals therealong, the frontal portions of said hook members being in a common vertical plane forward of said structure and terminating in article-engaging edge portions disposed in horizontal and vertical alignment, a plurality of other hook members pivotally supported on said structure in spaced relation to said first-named hook members and reaching forwardly through said plate-like hook members and then angularly upwardly with respect thereto, spring means biasing said other book members into rotation forwardly of said first-named hook members while permitting retraction with respect thereto, means to support said other hook members in said forward position with the free ends thereof terminating in article-engaging portions disposed in substantially the same horizontal and vertical plane below the article-engaging edge portions of said platelike hook members, and relatively large-area shoe members secured to the lower portion of said rectangular structure and having article-engaging faces disposed in a common plane with the front portions of said first-named hook members.

6. A lift truck according to claim 5, in which said shoe members are pivotally afiixed to said structure.

7. A lift truck according to claim 5, in which said shoe members are pivotally aflixed to said structure and are guided for limited rotation from the vertical.

8. A lift truck according to claim 5, in which certain of said other hook members project through said firstnamed hook members and are releasably supported thereby in operative position.

References'Cited in the file of this patent UNITED STATES PATENTS 1,835,431 Ryerson Dec. 8, 1931 2,304,649 McDaniels Dec. 8, 1942 2,447,300 Williams Aug. 17, 1948 2,582,663 Weiss Jan. 15, 1952 2,620,937 Halloran Dec. 9, 1952- 2,634,875 Trautner Apr. 14, 1953 2,650,732 Hartquist Sept. 1, 1953 2,650,733 Blatz Sept. 1, 1953 2,670,095 Blatz Feb. 23, 1954 2,676,672 Lepkowski Apr. 27, 1954 2,676,722 Ulinski Apr. 27, 1954 2,693,289 Ulinski Nov. 2, 1954

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