US2719643A - Material handling attachment for a fork lift truck - Google Patents

Description

4 Oct. 4, 1955 w. J. MCDONALD ,719,643

MATERIAL HANDLING ATTACHMENT FOR A FORK LIFT TRUCK Filed Dec. 3, 1953 W/ am 4/. McDona/a JNVENTOR.

By 9M ATTORNEY $113165 Paten r MATERIAL HANDLING ATTACHMENT FOR A FORK LIFT TRUCK William J. McDonald, San Antonio, Tex. Application December 3, 1953, Serial No. 395,988 1 Claim. .(Cl. 214-620) This invention relates ,to material handling apparatus and more particularly to improved load carrying means adapted'to be used with a fork lift truck.

Conventional fork lift .trucks such-as, for example, the Hyster fork lift truc'k, are designed so that the arms of the fork may be moved both laterally 'and vertically by hydraulic, mechanical, or electrical means. -Lateral movement of the arms brings them closertogether or farther apart, as desired, while vertical movement lowers or raises them as necessary for loading, transporting, and unloading the object being handled. In lifting boxes and the like, which can be readily tilted, the fork arms are lowered and then moved under the raised edge of the box, the bottom of the box is permitted to engage the top of the arms, and the fork is then raised in order to transport the article. In the case of handling articles packaged in relatively soft containers, handling devices with projecting spines or the like are often provided on the fork arms. Upon laterally moving the arms toward the object to be carried between them, the spines will enter into and grab the soft material, eliminating the necessity of manually lifting or tilting the article. In the case of the handling of many rigid articles, moreover, devices have been designed for use with the arms of the fork lift truck to accommodate the special shape of the article to be lifted. To date, however, no simple and practical means has been provided for handling substantially flat and relatively thin metal objects and the like, without the necessity of manual loading and unloading. This problem is particularly serious in the case of handling the running boards used to bridge the gap from the loading platform to the door threshold plate of railway freight cars, or from car to car, which running boards generally weigh over 300 pounds and require at least two men to load and unload them from the lift truck. This manual operation involves a considerable hazard to hands and fingers because of the weight of the running boards and the relative sharpness of their edges. Many of the older running boards are merely flat plates of steel, while the more modern running boards have a slight curvature along one axis. The handling of either type of running board by lift trucks presents a very serious and special problem both from the standpoint of injury to employees and the amount of time required.

Accordingly, it is an object of my invention to provide improved means for lifting and handling substantially fiat and relatively thin metal plates.

It is another object of my invention to provide load carrying apparatus adapted to be supported on the arms of a fork lift truck so that the truck operator can load, transport, and unload metal plates such as freight car running boards without the necessity of any manual handling of the plates.

In carrying out these objects in the presently preferred form of my invention I provide a telescoping lifting apparatus provided at each end with grab hooks. Suitable brackets are attached to the telescoping apparatus by which it can be supported on the two arms of a fork lift 2,719,643 Patented Oct. 4, 1955 truck of the type inwhich the arms can be moved both laterally and vertically. Upon "lowering of the arms, the telescoping apparatus is lowered until the grab hook portions at its ends are below the undersurface of the plate. Then the arms are movedi'laterally toward each other, telescoping .the apparatus and sliding .the hooks beneath the plate. The plate is then supported on the hooks while the truck, after the arms. are suitably raised, is driven to any desiredlocation.

In the accompanying drawings Fig. l is a side view of a conventional fork lift truck to which my lifting apparatus have been applied, showing the lifting of a freight car running board of modern design; Fig. 2 is a front view of the same lift truck showing my lifting apparatus with its hooks supporting the, edges of a freight car running board of conventional flat'de'sign', to the edges of which rivets have" been added; :Fig. 3 is a detailed side view, partly in section, of one end of my improved lifting apparatus, showing the telescoping tubes and one of the hooks; and Fig. 4 :is a section taken along the lines 4-4 of Fig. 3.

Referring now to Figs. 1 and 2 of the drawings, a conventional fork lift truck 1 having arms 2 and 3 is shown with the arms in a partially elevated position. Suspended from the arms 2 and 3 is my telescoping material handling apparatus. This apparatus includes a pipe or other tubular member 4 of relatively large diameter and another pipe 5 of smaller diameter, the pipe 5 extending into and being slidable within the pipe 4. On the pipe 4 and 5 are secured, preferably by welding, suitable hangers 6 and 7. Each hanger is formed, in the preferred embodiment as shown in Fig. 4, from a single piece of sheet metal bent double with diverging portions 8 and 9 forming a pocket for receiving the pipe. The portions 8 and 9 terminate in oppositely extending end members 10 and 11, respectively, for a purpose described hereinafter.

The upper portions .12 of the hangers vided with suitable openings of the lift truck, so that the apparatus will be supported thereon. These openings are of only slightly greater width than that of the fork arms, so that the two pipes move almost immediately in response to lateral movement of the arms.

The free ends of the tubes or pipes 4 and 5 are formed into the shape of grab hooks 14 and 15 preferably by heating followed by flattening and bending. The hooks 14 and 15 slope downwardly and inwardly, and are adapted to be moved toward or away from each other as the tubes 4 and 5 are telescoped or extended by lateral movement of the truck arms.

As shown in Fig. l, the flat end members 10 and 11 engage the top surface of the running board, preventing tilting as it is lifted and transported. This permits the hooks 14 and 15 to be formed with a relatively small contact surface, as thesteadying effect of the hanger end members makes it unnecessary for the hooks to accurately balance the boards.

When my lift apparatus is used the operation of the fork lift truck in moving freight car running boards is relatively simple. In the case of the more modern designs of running boards the oval shape causes the center line of the board to be suificiently elevated to permit the hooks to slide beneath, while boards of the older flat design may be provided with one or more rivets on each side of the board to provide a space in the order of of an inch between it and the floor, or between it and the next board when they are stacked. In preparing for handling these boards the telescoping lift apparatus is removed from its place of storage and into position on the truck arms. The truck arms are lowered and then moved laterally together until the hook 6 and 7 are pro- 13 for receiving the arms portions of the respective ends of the apparatus slide beneath the undersurface of the running board. The arms are then raised to a suitable carrying position, the truck driven to the desired place, and the arms then are lowered either to set the running board in place or to store the board for future use. Then the arms of the truck are moved laterally outwardly to free the hooks. This operation eliminates handling the plates manually from the platform to the freight car and from car to car, reducing the hazard involved and resulting in a considerable saving of time.

While I have shown a particular embodiment of my invention, it will be understood, of course, that I do not wish to be limited thereto since many modifications may be made; and I therefore contemplate by the appended claim to cover any such modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

A freight car running board lifting and handling device for use with a fork lift truck of the type having laterally and vertically movable arms, comprising a pair of telescoping tubular members, a separate hanger on each of said tubular members with each hanger forming a slot for receiving an arm of said truck for support thereon, hook members on the free ends of said tubular members, said hook members being inwardly turned and providing an inclined surface for engagement with the underside of the running board, and substantially fiat load balancing members fixed to each of said tubular members and adapted to engage the top of said running board at areas spaced laterally from the areas of engagernent of said hook member surfaces.

References Cited in the file of this patent UNITED STATES PATENTS 2,461,678 Christensen Feb. 15, 1949 2,490,772 Benner Dec. 13, 1949 2,512,409 Adde June 20, 1950 2,562,247 Van Schie July 31, 1951 2,571,550 Ehmann Oct. 16, 1951 2,613,823 Johns Oct. 14, 1952 2,655,278 Daniels Oct. 13, 1953 FOREIGN PATENTS 137,952 Australia July 13, 1950

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