US2796187A - Mobile loading fork lift machine - Google Patents

Description

June 18, 1957 GIRARDI 2,796,187

MOBILE LOADING FORK LIFT MACHINE Filed June 14. 1954 S'Sheets-Sheet 1 LM 1NVENTOR..

' fi m/w 4- 6 4 /71 Iff/ June 1957 A. L. GIRARDI OBI-LE LOADING FORK LIFT MACHINE 3 Shee'ts-Sheet 2 Filed June 14. 1954 MW 1 M E\ A. L. GIRARDI MOBILE LOADING FORK LIFT MACHINE June 18, 1957 3 Sheets-Sheet 3 Filed June 14, 1954 United States Patent MOBILE LOADING FORK LIFT MACHINE AntonioLawrenceGirai-di, Stockton, Calif.

Application June 14, 1954,'Serial N0.'436,392

lClaim. (Cl. 214-731) This-inventionrelates to loading mechanism,'and particularly to a mobile fork lift 'for lifting and stacking boxes and the like.

It is among the Objects of this invention toprovid'e a mobile lift adapted for operation in orchards, fields and vineyards, and operable for loading boxes onto trucks or platforms in high tiers.

Another object is to provide a mobile fork lift in which the lifting fork is movable transversely to deposit boxes in closely abutting stacks.

A further object is to provide a fork lift in which the fork may be tilted slightly during the lifting operation to guard against inadvertent tumbling of'stacked-boxesfrom the fork.

Another object is to'provide a mobile fork lift provided with a hold-down mechanism for clamping a'-1oad on the fork during movement from a loading to an unloading position.

It'is also an object of this invention to'provide a mobile fork-lift provided with'means actuated byhydraulic pressure produced by the power plant'of the vehicleand controlled by the operator of the vehicle fromthedrivers seat.

The invention'has other'objects and features of advantage, some of which with the foregoing will Lbe'explained in the following description of that 'form of the invention illustrated in the drawings. -It is to beunderstood that the invention is not *limited to the embodiment shown in the accompanying drawingsas it may be embodied in other forms within the definition of the appended claim.

In the drawings:

Fig. 1 is a'plan view of portions of a mobile fork lift embodying the present invention, parts being broken away, and parts being-illustrated'indiagrammatic form.

Fig. 2 is a fragmental-perspective -view of the for'krlift guide "and control mechanism.

':Fig. 8 is a fragmental frontelevational view of portions \ofithe lift mechanism-of Figs. 1-and 2.

'=Fig. 4 is a fragmental sectional view illustrating the rmountingrofthe fork lift for-vertical andtransverse move- :ment, :theplaneof the section being in'dicated by the line .4 -i4.ef Fig.2..

Fig. S5 is .a sectionaLdetail view, the plane of the section being indicated .b.y.the line .55 of Fig. 4.

Fig. 6 is a fragmental detail view'illustrating a 4-wheel asteerin g connection.

versely with respect to the vehicle to permit movement of a load laterally into close proximity with a previously stacked load. The fork lift ismoved vertically, laterally and pivotally by means of hydraulic pressure applied to pistons operably connected to the moving parts and controlled by valves accessible to an operator while seated in the drivers seat of the vehicle. Preferably the vehicle is of the four-wheel type provided -with. four-wheel drive and four-wheel steering connections to facilitate operation over rough terrain, and to permit turning .upon a very short radius. A hold-down member is provided for clamping a loadonto the fork lift duringmovement from a loading position to an unloading position.

In terms of greater detail, the mobile fork lift of the present invention, in the embodiment selected .for illustration, comprises a vehicle having a frame designated in general by the numeral 1 supported by wheels 2, and having an internal combustion engine 3 mountedon-the rearward end thereof. The engine 3 is preferably arranged to deliver power to all fourof the wheels 2 through suitable four-wheel drive connections of conventional form and arrangement. A hydraulic pump of any suitable size and construction is mounted upon the frame 11 in association with the engine .3, and is operated thereby to provide hydraulic'pressure for actuating'moving parts of the lift mechanism. Since the drive mechanism and hydraulic pressure means of the device are well known, 'andthe particular construction thereof does not form a part of the present invention, a detailed disclosure .and description of the structure thereof is "herein unnecessary and is omitted herefrom.

Upon the forward end of the vehicle frame 1 is secured a guide'frame comprising a pair of upright channel members 4 and atop cross piece "5. The guide frame is pivoted to the vehicle frame by mounting plates 6 engaging a shaft 7 extending transversely across the forward end of the frame '1. The guide frame is normally held in a substantially vertical position, and is arranged to be tilted about the shaft 7, to incline its upper endslightly toward the rear, by means of a piston rod 8 actuated by hydraulic pressure introduced into a cylinder9 through a-suitable valve controlled connection 10. The cylinder 7 is pivotally anchored to the frame 1 by a pivot block 1 1, as best indicated in Fig. 2 of the drawings.

'Slidably'telescoping with the channel guide members 4 are extensible guide members 12 of channel shaped cross section movable to extend upwardly'from the top of the guide frame. The upper ends of the extensible'members 1-2 are connected by a yoke comprising a pair of arms =14 secured in transverse alignment to a mounting block 16. Braces I7 incline from the block '16 to the tops :of the-channels 12. 'The arms are provided with=bearing portions at the outer ends thereof upon which are journaled sprockets '18. The block 16 'is secured-to the upper end-of apiston rodl 9- operating through the upper head of a vertically disposed cylinder .21. The piston rod 19 is arranged to move the extensible channels 12 :upwardly from their normal position, telescoped withinthe channels 4-, to :extend upwardly there'from to a desired :height in 'respons'e to hydraulic pressure operating'through aa'suitablezvalvecontrolled connectionZZ-Z.

A pair of cross guides 23 are mounted upon the guide members 4 and 12 by means of brackets 24 rigidly secured to the cross guides adjacent the upright guides 4 and 12. Each bracket 24 is provided with a pair of rollers 25 engaged between the inwardly disposed flanges of the channel members 12. Fittings connect the upper and lower brackets '25 associated with the corresponding guides so that the brackets with their rollers are joined to form a carriage movable vertically up and down along the upright guides.

A pair of lifting fork members 27 are slidably mounted upon the cross guides 23 by means of slide bearing arms 28. The fork members 27 are provided with piston rods 29 operating through opposite ends of a cylinder 31. The cylinder is provided with suitable connections 32 operable for directing hydraulic pressure into the cylinder for displacing piston means connected to the rods within the cylinder, whereby the fork members may be shifted laterally with respect to the upright guides at any position therealong. The fork members 27 are of approximately L-shape, with lower arms forwardly disposed to engage and support a load.

Sprocket chains 33 extend over the sprockets 18 and are anchored at one end'to the fork carriage formed by the cross guides 23, brackets 24 and rollers 25. At the other end, each chain is anchored to a cross bar 34 secured to the upright guide channels 4 near their upper ends.

Across the front end of the guide frame is mounted a guard frame 36 upon which is slidably mounted a holddown frame 37. A pressure cylinder 38 is mounted in spaced parallel relation to the cylinder 24; and a piston rod 39, connected to a piston within the cylinder, is arranged to move the hold-down frame into clamping engagement with a load supported upon the fork. The cylinder 38 and guard frame 36 are secured to and are movable with the upper cross guide 23. The hold-down frame is movable independently of the fork members into clamping engagement with a load supported by the fork members. After it has reached its clamping position the hold-down frame is movable with the fork members as they are raised and shifted to deposit a load upon a truck or platform.

Controls for the hydraulic pressure directed to the cylinders 9, 21, 31 and 38 are preferably mounted at a point accessible to the operator of the vehicle so that the fork may be operated to engage, clamp, tilt, elevate, shift laterally and finally deposit a load without need for the operator to descend from the drivers seat. Connections to the movable cylinders are of fiexible hose adapted to accommodate movement of the various cylinders through their full range of movement.

In operation for loading lug boxes of fruit onto a truck for transportation from an orchard to a point of shipment or packing, loaded boxes are stacked, preferably upon pallet boards, at various points throughout the orchard. The vehicle is driven to advance the lift portions of the lift forks 27 under a stacked pile of boxes. After the fork members have been properly positioned under the stacked boxes, the hold-down frame 37 is moved downwardly to clamp the boxes against the fork members. Hydraulic pressure is then applied through the cylinder 21 to move the extensible guides 12 upwardly along the upright guides 4. As this movement is initiated, the piston rod 8 is moved to tilt the guide frame bodily about its pivot support 7, so that gravity will tend to move the boxes against the guard frame 36. This action, coupled with the clamping action of the hold-down frame, prevents the stacked boxes from tipping and tumbling from the fork as they are raised to a desired elevation and transported to an unloading station.

As the extensible guide channels are moved upwardly through the upright guides 4, the chains 33 are moved over the sprockets 18 to raise the fork carriage and fork members upwardly. Thus, the ends of the chains which 4 are anchored to the cross piece 34, remain stationary and, as the sprockets are raised with the guide channels 12, the chain is drawn over the sprockets and the lift fork is progressively raised.

The load is elevated sufficiently to clear ground obstructions as it is transported to a truck or platform onto which it is to be loaded. The fork is then elevated to whatever height is necessary to deposit the load upon the truck or platform. In practice, stacks of boxes, stacked five or more high, may be easily lifted and deposited upon a truck. When the desired elevation is reached, the fork may be shifted laterally to deposit each stack flush against a previously deposited stack. This tends to stabilize the load upon a truck, and to utilize all available space. A second tier of stacks may then be deposited upon pre viously deposited stacks to load the truck to its maximum capacity. The upright guides may be quite high and the lifting action of the sprocket chains 33, operating over the sprockets 18, permits boxes to be readily stacked to a height of twelve feet or more.

The steering mechanism, designated in general by the number 41, preferably actuates all four wheels of the vehicle. A hydraulic booster 42 may be provided to facilitate the steering, as indicated in Fig. 6 of the drawmgs.

By employing four-wheel drive and four-wheel steering mechanism, the vehicle may be driven over plowed land between rows of trees, and may be turned upon the short radius necessary to advance from row to row across an orchard. The rearwardly tilted support and the clamping action of the hold-down frame permits the device to progress over broken surfaces without loss or injury to the load. Likewise, the hydraulic piston and chain lift and lateral shifting action permits boxes to be stacked closely and neatly to a greater height than has been practicable with fork lift equipment heretofore available. The device, of course, is useful for many purposes other than field and orchard use; and the invention is in no way limited to that particular utility.

Having thus described the invention, what I claim is:

A loading machine comprising a power driven vehicle having four-wheel drive and four-wheel steering connections, a fork lift mounted for vertical and transverse movement relative to the vehicle, hydraulic pressure means for actuating the fork lift vertically and transversely relative to the vehicle, and hydraulically actuated means for clamping a load onto the fork during lifting movement thereof.

References Cited in the file of this patent UNITED STATES PATENTS 2,421,472 Way June 3, 1947 2,483,745 Vossenberg Oct. 4, 1949 2,545,021 Ooupland et a1 Mar. 13, 1951 2,571,550 Ehmann Oct. 16, 1951 2,578,802 Heidrick et a1 Dec. 18, 1951 2,611,497 Backofen Sept. 23, 1952 2,621,811 Lull Dec. 16, 1952 2,621,822 Melin Dec. 16, 1952 2,663,443 Schenkelberger Dec. 22, 1953 2,684,165 Hill July 20, 1954 FOREIGN PATENTS 144,506 Australia Dec. 28, 1951

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