US2987339A - Articulated lifter - Google Patents

Description

June 6, 1961 L. G. KAPLAN ETAL 2,987,339

ARTICULATED LIFTER Filed Jan. 27, 1960 a Sheets-Sheet 1 llllllr INVENTORS Lows G-KAPLAN Dommm .Mono

June 6, 1961 L. G. KAPLAN ETAL 2,987,339

ARTICULATED LIFTER 3 Sheets-Sheet 2 Filed Jan. 27, 1960 S m w m m LOUIS G. KAPLAN Dommm J. Mono June 6, 1961 Filed Jan. 27, 1960 L. G. KAPLAN ETAL 2,987,339

ARTICULATED LIFTER 3 Sheets-Sheet 3 uvmvrons Louls G. KAPLAN BY DOMINIK J.Moao

United States latent Oflice 2,987,339 Patented June 6, 1961 2,987,339 ARTICULATED LIFTER Louis G. Kaplan, 'Evanston, and Dominik J. Moro, Villa Park, Ill., assignors to Cullen-Friestedt Company, -Chicago, Ill., a corporation oflllinois Filed Jan. 27, 1960, Ser. No. 4,999 '5 Claims. '(Cl. 294-67) The present invention relates to lifting and transporting mechanism and has particular reference to an articulated lifter capable of use in lifting and transporting either one or two objects without requiring any adjustment or modification whatsoever of the mechanism in adapting the same to either its single or double use.

The improved lifting and transporting mechanism comprising the present invention has been designed for use primarily in connection with the lifting and transportation of sheet metal stock in coil form. Coils of the type with which the lifter mechanism of the present invention is concerned consist of elongated strips or sheets of sheet metal stock wound in convolute fashion to produce a series of continuous laminations and produce, in the final shape of each coil, a generally tubular integral laminated spool-like structure, the innermost convolutions of which define a central ibore through the spool.

'The handling of sheet metal coils of the character set forth .above, either at the steel mill for loading purposes, .or at .a consumer location where the coils are distributed through the plant for unwinding =at punch presses, for example, presents a problem due to the relatively great mass and weight of these coils, as well as due to the fact that their cylindrical shape makes them awkward to handle. Although special up-ending coil handling mechanism has been designed which is capable of receiving .a .coil in one position and depositing the same in a different position at another remote location, an extremely simple and effective type of non-upending coil lifter which is widely in use is known as a C-hook lifter. Such a lifter consists essentially of a O- shaped structure having its upper and lower legs horizontally and in parallelism and having a' connecting bight portion extending vertically. The upp r overlying. leg is provided with an eye which sometimes is in the form of a hole through the leg, and sometimes is in the form of a hail, the eye being so disposed that when the lifting hook of an overhead crane is passed therethrough and the entire C-hook lifter elevated, the mechanism will assume a degree of stable equilibrium with the lower leg extending parallel to the floor or other supporting surface. The crane may be manipulated to cause the lower leg of the C-hook to become aligned with and enter the bore of a given coil positioned horizontally on the supporting surface, after which vertical displacement of the c-hook up a dly i l serve to lift th il f om the upporting surface and cause the coil to be suspended from the lower leg with the axis of the coil remaining substantially horizontal and without causing appreciable tilting f' e Q kr L ft rs of th g ne a typ r cei e the il in a ho zo a p sit and d p i t e ame in such horizontal position with no provision being made for ipn ng he co s.

In an efiort to accommodate the simultaneous lifting and transportation of two similar relatively massive coils, dual Q-hook-coil lifters-have been devised. These lifters consist essentially of two. parallel fi-hooks rigidly connected together by one or more connecting bars or struts including an upp r strut which extends between the medi-v al regions of the top legs. of the two C-hooks and: which itself is provided with a medial eye designed. for re ception of the lifting hook of the overhead crane. While such compound structures serve, efiiciently in the lifting;- and transportation of two coils of substantially equal size and weight, they are not readily adaptable for use in the lifting and transportation of a single coil due to the fact that the weight of a single coil thereon will cause tilting of the structure when it is elevated by the crane hook from the supporting surface. With the cage-like structure thus displaced from its normal horizontal position, the vertical center line of the crane hook will be displaced laterally from the vertical plane extending through the longitudinal axis of the coil so that it is difficult for the crane operator correctly to judge distances in placing the coil and, furthermore, the angular position of the structure as a whole, when the single coil is supported thereby, is such that interference is frequently ofiered by adjacent objects so that it is impossible, for example, to deposit the coil on the supporting surface in close proximity to a wall or to a tall object.

Another limitation that is attendant upon the construction and use of conventional dual C-hook lifters resides in the fact that such structures will become unbalanced when employed for lifting and transporting tWo coils which vary appreciably in weight, the heavier of the two coils presenting an unbalanced weight on one side of the structure tending to elevate the other coil and, in so elevating it, moving it to an undesirable position of wide lateral displacement which renders handling of the lifter by the crane operator awkward.

The present invention is designed to overcome the above-noted limitations that are attendant upon the construction and use of present day single and dual C-hook lifters and, toward this end, it contemplates the provision of a novel form of lifter construction embodying two C-hooks, each capable of supporting a coil, and with the C-hooks being operatively connected together by articulated joints which operate, when a single coil'is operatively supported by the structure, to maintain the axis of the crane lifting hook vertically centered above the C-hook on which the coil is carried, regardless of which of the two C-hooks is employed for lifting purposes.

The provision of a dual C-hook lifter of the character briefly outlined above being among the principal objects of the invention, it is a further object of the invention to provide such a lifter which, when a single coil is supported thereby, consumes a minimum of free space and has a relatively narrow lateral spread so that there will be minimum interference with adjacent objects during crane manipulation.

It is a still further object of the invention to provide a dual O-hook lifter which is completely automatic in its operation, which is to say that the articulated joints thereof automatically adjust themselves to any given load without requiring manual presetting of the parts or any sort of attention whatsoever on the part of an operator except for the usual floor guidance of the device as a whole. Stated in other words, it is an object of the invention to provide an articulated dual C-hook lifter which may be applied to a single load or to a dual load without requiring manual adjustment, the application thereto of adapter parts, the removal therefrom of such parts, or any other attention whatsoever on the part of a floor operator other than the usual guidance of the device into loading position.

A similar and related object is to provide such a device which, when employed for lifting and transporting a single coil or other load, will, after lifting operations have commenced, automatically assume its position of maximum lifting effectiveness wherein the vertical axis of the crane lifting hook is coincident with the center of gravity of the coil and lifter.

Another and important object of the invention is to provide a dual 0-hook lifting device capable of handling two coils or other loads of unequal weight and which,

when such unequal loads are operatively supported by the device, will automatically assume a position wherein the center of gravity of the entire structure, including both the load and the elements of the lifter device, lies directly beneath and in the vertical plane of the lifting hook of the overhead crane hoist.

The provision of a coil lifting device of this character which is extremely simple in its construction, one which is comprised of a minimum number of parts and which therefore is unlikely to get out of order; one which is rugged and durable and which therefore will withstand rough usage; one which employs no intricate or special machined parts and which may therefore be manufactured at a relatively low cost; and one which otherwise is well adapted to perform the services required of it are further desirable features which have been borne in mind in the production and development of the present invention.

With these and other objects in view, which will become more readily apparent as the nature of the invention is better understood, the same consists in the novel construction, combination and arrangement of parts shown in the accompanying three sheets of drawings forming a part of this specification.

In these drawings:

FIG. 1 is a perspective view of an articulated lifter assembly constructed in accordance with the principles of the present invention and showing the same operatively suspended from an overhead hoisting crane;

FIG. 2 is a front elevational view of the lifter assembly shown in FIG. 1;

FIG. 3 is a side elevational view of the lifter assemy; a a

FIG. 4 is a rear elevational view of the lifter assembly;

FIG. 5 is a sectional view taken substantially along the line 55 of FIG. 4;

FIG. 6 is a front elevational view similar to FIG. 2, showing the position of the lifter assembly when the same is employed in connection with the lifting and transportation of a single, load;

FIG. 7 is a sectional view taken substantially along the line 7-7 of FIG. 3; and

FIG. 8 is a sectional view taken substantially the line 88 of FIG. 3.

Referring now to the drawings in detail and in partic lar to FIG. 1, an articulated lifter assembly constructed in accordance with the principles of the present invention has been designated in its entirety at 10. The lifter dis-1 closed herein constitutes a preferred form or embodialong tions 20 of the sheet metal, and the mandrel subsement of the invention. It is adapted to be attached to and used in connection with the lifting hook 11 associated with the crane of an overhead hoist. If desired, a power swivel 12 having a hook 14 may be interposed between the lifting hook 11 and the lifter 10. The lifter constitutes a medium or instruinentality for handling laminated sheet metal coils, such as the coils shown at 116 and 18 in dotted lines, in moving the coils from one location to another. As shown in FIG. 2, the lifter assembly 10 is capable of lifting, supporting and transporting a pair of coils, or, as shown in FIG. 6, the assembly may be employed for lifting, supporting and transporting a single coil. The necessary transition of the articulated lifter assembly to adapt the same to either a single ora dual load, as exemplified in FIGS. 2 and 6 respectively, takes place automatically, Without requiring adjustment or other attention on the part of a floor operator upon initial application of thelifte r to its load and the application to the load of a lifting force, all in a manner thatwill become clear presently as the nature of the invention is better understood. I

The coils 16 and 18 are of conventional design and in the environment of the lifter assembly shown herein these coils are equal in size and weight. Each coil consists of a single unitary elongated strip of flat sheet metal stock which has been wound in convolute fashion on a mandrel to produce a series of adjacent convoluquently withdrawn so that a spool-like article having a central bore 22 extending therethrough and presenting a substantially cylindrical outer surface 24 and substan tially flat end faces 26 is produced. The coils 16 and 18 are relatively heavy and may weigh as much as 90,000 pounds, and thus the lifter assembly 10 is, of necessity, relatively massive. The assembly 10 has been designed primarily for transporting one or two such coils at a time from one location to another with the lifter receiving the coils in a horizontal position and depositing the same in a similar position wherein the cylindrical surface 24 rests tangentially on the supporting surface at the time the coil is released.

The lifter 10 involves in its general organization a pair of specially constructed modified G- hooks 30 and 32 respectively, the two C-hooks being substantially identical in construction. Each C-hook is'in the form of a plate having an upper horizontalleg 34, a lower horizontal leg 36 extending parallel to the leg 34, and a connecting vertical bight portion 38. Each C-hook is substantially flat, which is to say that it is relatively. thin in transverse cross section with the two legs and connecting bight portion lying in the. same vertical plane.

The medial regions of the bight portions 38 of the two C-hooks 30-and 32 are connected together by means of a transverse connectinglink 40, the latter being of a composite nature as will be described presently. Similarly the medial regions of the upper horizontal legs of the two C-hooks are connected together by a transverse suspension link 42 and the latter link is capable of being supported medially of its ends from the lifting hook 14 of the overhead hoist 12 by means of a bail 44.

The connecting link 40 is of composite design and it is in the form of an elongated hollow tubular box-like structure including spaced vertical side plates 46 and spaced upper and lower horizontal plates 48 having their side edges welded to the inside faces of the vertical plates 46. At the'ends of the box-like structure, the plates 46 extend beyond the ends of the plates 48 and are welded to solid attachment ears 50 which are square in transverse cross sectionas best seen in FIG. 6. Each attachment ear is formed with a horizontal bore 52 therethrough, the function of which will appear presently.

Secured to and spaced from the rear end face of the bight portion 38 of each C-hook is an elongated vertical plate 54,'a series of spacer members 56 being welded at their ends to the C-hook and plate 54 respectively to maintain the plate in its spaced relationship. A pivot pin 58 having its enlarged head 60 seated within a countersunk recess 62provided in the outside face of the plate 54 extends through the plate and through the bore 52 and is secured in operative position by means of a cotter pin 64 which extends through an anchor plate 66-, and the pivot pin 58. A bushing 68 surrounds the pin 58 within the bore 52. The anchor plate 66 is welded to the rear face of the bight portion 38 of the C-hook. The arrangement of parts just described at each end of the composite link 40 serves as a strong and efiective pivotal connection between the link and the two C-hooks 30 I and 32 to which the link is attached.

The transverse suspension 42 is in the form of an elongated member having downturned attachment ears 70 at its ends. Each attachment ear 70 extends between a pair of spaced attachment plates 72 which are welded to the upper horizontal leg 34 of one of theC- hooks 30 or 32 as the case maybe and which project a slight distance thereabove. A pivot pin assembly including the pin proper 74, washers 76 and bushings 78 serves to pivotally connect the ends of the transverse suspension link 42 to theplates 72 and consequently to the C-hooks.

The medial region of the transverse suspension link 42 is formed with an upwardly projecting suspension ear 80 which is reinforced by the provision of two side plates 82 which are welded thereto. A pin 84 extends through threadedly received, on an end. of the pin. A cottec pin- 90 maintains the nut; 88 against turningrelative to the The distal end' of the upperhorizontal leg'34 of each C-hook has mounted thereon a counterweight assembly 92, such assembly consisting of a plurality of thick plates 94 secured together by bolts 26 with the entire assembly being welded to thedistal end face of-theleg 34. The two counterweight assemblies. serve to: compensate for the normally. unbalanced. weight. of the" relatively massive bight portions 38 of the C-hooks.

In the operation of the herein described articulated lifter assembly, assuming for example that it is desired to transport two coils 16 and 18 of equal weight from one location to another by means of the overhead hoist, the coils are positioned on the supporting surface with their axes extending horizontally and in parallelism and spaced apart a distance substantially equal to the spacing of the two C-hooks 30 and 32. The crane operator may then elevate the lifter mechanism 10 from the supporting surface a slight distance and with or without floor assistance, guide the lower legs 36 of the C-hooks into the bores 22 of the respective coils. Thereafter, upon elevating the structure 10, the coils will be picked up by the C-hooks and supported on the upper edges of the legs 36. It is to be noted at this point that the upper edges 100 of the legs 36 are arcuate in cross section so as to make a blunt band of contact with the bores of the coils. Since the coils are of equal weight, and since the articulated lifter mechanism is balanced on opposite sides of the lifting bail 44, the structure will assume the level position in which it is shown in FIG. 1 with both coils being supported at the same general elevation above the supporting surface. Deposition of the two coils at any desired location may be effected by the crane operator by a reversal of the operations just described.

When it is desired to lift and transport a single coil 18, from one location to another, the lower leg 36 of either C- hook 30 or 32 may be passed through the horizontally disposed coil bore 22 in the manner previously described with the structure 10 as a whole assuming the horizontal position in which it is illustrated in FIG. 1. Thereafter, upon elevation of the structure 10 by the crane operator, the weight of the coil 18 will initially restrain the C-hook which has thus been projected into the bore '22 and prevent the same from immediately rising from the supporting surface. As the lifting book 14 continues to rise, the various elements of the articulated structure, including the upper and lower connecting link members 42 and 40, and the upper horizontal legs 34 of the two C-hooks 30 and 32 respectively, together with approximately onehalf of the two vertical bight portions 38, will function in the manner of an articulated parallelogram so that the link members 42 and 40 will move into positions of close proximity to each other as shown in FIG. 6 with the axis of the lifting hook and of the bail 44 moving into the vertical plane of the axis of the coil 18. Thus, the center of gravity of the structure 10 with the coil 18 supported thereon will lie directly beneath the point of ap plication of lifting tension. Furthermore, in this position of the parts, the lifter mechanism 10 as a whole occupies but very little lateral space and, in fact, but little more lateral space than that occupied by the coil itself, so that considerable freedom of movement of the lifter in close quarters is made possible.

The lifter mechanism described above is self-equalizing, which is to say that in the event that two coils of unequal weight are positioned on the two C-hooks 30 and 32 respectively, the center of gravity of the lifter with the coils thereon will assume a position directly beneath the lifting hook 14 of the hoist 12.

While one specific embodiment of the improved artic ulated; dual: G-hook: mechanism of the present invention has been shown and described herein for illustrative purposes, it will be understood that the illustrated form of theinvention does not by'any means indicate all thedifferent forms of apparatus suitable for the functions intended; the form illustrated being only one of those which have been developed. for commercial application. The invention therefore is; notto be limited to the exact arrangement of parts shown in the accompanying drawings. or described in this specification and various changes in; the details of construction may be resorted to without departing from the spirit of the invention. Only insofar as the invention; has particularly been pointed out in the accompanying claims is the same to be limited.

Having thus described the invention what we claim as new and desire to secure by Letters Patent is:

1. In an articulated lifter of the character described, in combination, a pair of C-hooks each having an upper horizontal leg, a lower horizontal leg and a vertical connecting bight portion, a lower horizontal connecting link pivoted at its opposite ends to said C-hooks respectively at corresponding elevations thereon, a transverse suspension link pivoted at its opposite ends to said C-hooks respectively at corresponding elevations thereon above the elevations at which said connecting link is pivoted, said connecting link and said suspension link, in combination with portions of the O-hooks, providing in effect an articulate collapsible parallelogram structure, and a lifting bail pivotally connected to said transverse suspension link substantially midway between the ends of the latter and designed for lifting engagement with the lifting hook of an overhead hoist.

2. In an articulated lifter of the character described, in combination, a pair of substantially parallel C-hooks each having an upper horizontal leg, a lower horizontal leg, and a connecting bight portion, a transverse con necting link pivoted at its opposite ends to the bight portions of said C-hooks respectively and at corresponding elevations thereon, a transverse suspension link pivoted at its opposite ends to the upper horizontal legs of said C-hooks respectively, said suspension link and said connecting link, in combination with an adjoining portion of each bight portion, providing in effect an articulate collapsible parallelogram structure, the plane of which extends at a right angle to the planes of said C-hooks, and a lifting bail pivotally connected to said transverse suspension link substantially at the midpoint thereof and designed for lifting engagement with the lifting hook of an overhead hoist.

3. In an articulated lifter of the character described, in combination, a pair of substantially parallel C-hooks each having an upper horizontal leg, a lower horizontal leg, and a connecting bight portion, a transverse connecting link pivoted at its opposite ends to the bight portions of said C-hooks respectively and at corresponding elevations thereon, a transverse suspension link pivoted at its opposite ends to the upper horizontal legs of said C-hooks respectively, said suspension link and said connecting link, in combination with an adjoining portion of each bight portion, providing in efiect an articulate collapsible parallelogram structure, the plane of which extends at a right angle to the planes of said C-hooks, and a lifting bail pivotally connected to said transverse suspension link and designed for lifting engagement with the lifting hook of an overhead hoist, said lifting bail being pivoted to the transverse suspension link at a point which lies directly above the center of gravity of the lifter as a whole and at a point above the center of gravity of the suspension link.

4. In an articulated lifter of the character described, the combination set forth in claim 3 wherein said connecting link is pivoted to said bight portions of the respective C-hooks at points which are substantially midway in combination, a pair of C-hooks each having an upper horizontal leg, a lower horizontal leg, and a connecting bight portion, a transverse connecting link pivoted at its opposite ends to the bight portions of said O-hooks respectively and at corresponding elevations thereon, a transverse suspension link pivoted at its opposite ends to the upper horizontal legs of said C-hooks respectively, said suspension link and said connecting link, in combination with an adjoining portion of each bight portion, 1

providing in effect an articulate collapsible parallelogram structure, the plane ofwhich extends at a right'angle to the planes of said C-hooks, and means on said transverse suspension link midway between the ends of the link and above the center of gravity of the latter afiording a downwardly facing shoulder for receiving the upward thrust of the lifting hook of an overhead hoist.

References Cited in the file of this patent UNITED STATES PATENTS 1,541,090 Yunkes June 9, 1925 FOREIGN PATENTS 1,102,250 France May 4, 1955- 791,430 Great Britain Mar. 5, 1958

Images