Shelf Handling Device

Abstract

A shelf handling device includes vertically extending masts with either top or bottom guide wheels which are adapted to move along trackways between shelves and which includes a lower base with a basket stand providing a reinforcement for the mast and which includes four columns interconnected by longitudinal and transverse beams which carry a load receiving means such as a lift truck or extendible load receiving table.

Description

SUMMARY OF THE INVENTION

This invention relates in general to the construction of shelf handling and in particular, to a new and useful shelf handling device having an upstanding mast formed by spaced apart vertical mast members which are connected at their bottom end to a basket stand of a lift truck which is movable vertically along the masts, the truck also being movable, along with the masts, along a shelf corridor on a defined trackway.

Shelf handling devices of the type with which the invention is concerned include an operator's stand for the operator so that he can move along the shelves and move upwardly with the lift stand to remove stored material from the shelves or to store it thereon. In order to facilitate this handling of storage material the lift trucks of the known shelf handling devices are provided as needed with various load carriers, for example, with fork-lifts or telescoping tables which are extendible in transverse directions and which facilitate the placing in and taking out of storage of the various shelf items. In accordance with the shelves to be handled and with the load carriers which are provided at the lift truck, the operators entrance to the stand on the lift truck is provided from the front end or if this is not possible due to any existing load carriers, it is located on the side of the lift truck opposite to the lift masts. Such an arrangement, however, involves the disadvantage that for the operators to step in and out, the lift truck must be run out of the shelf corridor until the entrance is cleared. The diversity of requirements for the load carriers to be arranged at the lift carrier force the manufacturer of the shelf handling device into a manufacturing program of a great number of different truck lift designs; which, of course, is very unprofitable.

In the construction and design of lift trucks, special attention must be given to the transmission and removal of the vertical forces which originate from the loads and the dead weight of the lift truck and of the load carriers which are arranged at the load as well as the moments or torques imparted by the suspension and the drive of the lift truck. Fork lifters require an extraordinary bending and torsional stiffness of the lift truck frame or stand. Access to the stand for the operator weakens the cross section thereof and loads the receiving tables and produces high vertical forces. Consequently, it is hardly possible with the known shelf handling devices to replace individual load carriers by others, for example, tables by fork lifters, or lateral operator accesses by an access on a longitudinal side, in order to take account of changed operating conditions or to expand the possibilities of existing devices.

In accordance with the invention, there is provided a shelf handling device which is constructed with a base stand which is movable upwardly and downwardly in respect to a vertical mast and which is of such a sturdy construction, so that the load receiving means, for example the supporting tables, or forks, can be constructed in an optimum manner adequately adapted to the particular storage conditions. With the inventive construction, the manufacturer of such shelf handling devices may manufacture certain portions of the device as standard elements unchanged in all of the various designs so that they may be manufactured in relatively large quantities. These basic elements are supplemented by independently produced elements of uniform design sized to the variations required. Such changes and additions may be installed subsequently, that is after delivery of the unit.

In accordance with the invention, the lift stand is constructed with four columns which are interconnected by longitudinal and transverse beams in order to dispose load receiving means and access doors at the columns. A shelf handling device with such features may be provided with any desired load receiving means in accordance with the customers' desires, and access to the stand for the operator may occur from the side which does not carry a load receiving means. The columns on the lift mast side are interconnected by a traverse type longitudinal beam and the columns on the outer side away from the mast are interconnected by an additional longitudinal beam. The longitudinal beams of opposite sides are interconnected by two transverse beams. The transverse beams are preferably made of L-shaped configuration. The transverse beams transmit the vertical forces and moments acting on the columns farther away from the lift masts to the longitudinal beam arranged between the columns on the lift mast side which also receive the vertical forces and moments and conduct them into a cable for moving lift truck vertically on the masts.

The longitudinal and transverse beams are, in accordance with a feature of the invention, dimensioned to accommodate the highest moment to be absorbed by the two columns in order to permit the fork lifters, vertically adjustable lift tables, and/or folding tables to be arranged on both sides of the lift truck at the columns, and to arrange at the longitudinal side of the lift truck stand further removed from the lift mast at one of the two ends of the stand, an access door permitting access to the stand without removal of the loads.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention .

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a front elevational view of a floor traveling shelf handling device having a lift mechanism drive at the bottom thereof shown in a direction crossways to the direction of travel and constructed in accordance with the invention;

FIG. 2 is a section taken along the line II--II of FIG. 1;

FIG. 3 is a section taken along the line III--III of FIG. 1;

FIG. 4 is a view similar to FIG. 1 of another embodiment of shelf loader;

FIG. 5 is a side elevational view of the device indicated in FIG. 4; and

FIG. 6 is a top plan view of the device indicated in FIGS. 4 and 5.

GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings in particular, the invention embodied therein in FIGS. 1 to 3 comprises a lift truck generally designated 1 which is movable vertically upwardly and downwardly in respect to two upright lift masts 2, 2 by the action of a lift mechanism drive (not shown). The lift truck 1 together with the lift mast are mounted so that they be moved together along the shelf corridors and for this purpose a travel drive 4 located at the bottom of the truck 1 is arranged to drive rollers 50 which run over rails 5. The lift truck 1 includes a basket portion or stand 7 for the operator. The stand carries a treadle 8 and preferably, on the lift mast side, control devices 51 for the operation of the truck. The lift mast side is provided with safety means for the protection of the operator and in particular, the overhead roof 9.

In accordance with the invention, the four corners of the stand 7 are formed by columns 10, 11, 12 and 13. The two columns 10 and 11 on the lift mast side are rigidly interconnected by a traverse type longitudinal beam 14 which extends approximately at mid-height of the columns. Within the two columns 10 and 11, two L-shaped transverse beams 15 have an upper leg fastened in a symmetrically equal manner to the longitudinal beam. These two transverse beams 15 carry the foot board 8 and are fastened at the outer end of their other leg to a longitudinal beam 16 which rigidly connects the two columns 12 and 13 at the side further away from the lift mast 2.

When smaller loads, in the order of magnitude of 200 kg., are to be lifted, one L-shaped transverse beam would be sufficient.

By constructing the stand 7 with this strong frame construction, there results an especially torsionally and bending stiff construction. Vertical forces and moments acting from the load receiving means on the columns 12 and 13 are transmitted through the longitudinal beam 16 and the transverse beams 15 to the longitudinal beam 14 without burdening the lateral walls of the lift truck or the treadle 8. In addition, vertical forces and moments acting on the corner columns 10 and 11 which are located on the lift mast side are transmitted to the longitudinal beam 14. The weld connection between the longitudinal beam 14 and the columns 10 and 11 is relieved of the forces and moments transmitted into the longitudinal beam 14 through the columns 12 and 13. The moments thus transmitted to the longitudinal beam 14 are also transmitted to the lift mast 2 while the vertical forces are transmitted to the cable moving the lift truck vertically.

The columns 10, 11, 12 and 13 of the transverse beams 15, and the longitudinal beams 14 and 16 are so dimensioned as to strength that they are able to absorb the highest moment which can occur in the load receiving means in question for the attachment to the lift truck under the most unfavorable load distribution. This thereby provides a possibility for using the lift truck frame structure for all possible customary requirements provided the dimensions are changed correspondingly. Thus, for example, the lift truck 1 of the form of construction of FIG. 1 is provided on the broad side with a fork lifter 20 and on the opposite broad side with a vertically displaceable table 21. Since in a lift truck equipped with such load receiving means access cannot occur from the broad side an access door 22 is arranged on the longitudinal side, namely at one end of the longitudinal side so that the lift truck must be moved out of the shelf corridor by as small an amount as possible. A similar access might be provided additionally or alternatively at the other end of the longitudinal side of the lift truck as the walls of the lift truck have no supporting functions to fulfill.

It is also possible to provide a folding table in place of one or both load receiving elements 20 and 21 and to create additionally or alternatively an access to the stand from the broad side of the lift truck.

A variation of the type referred to above is shown in the embodiment of FIGS. 4 to 6 wherein similar parts are similarly designated but with primes. The travel drive generally designated 52 for driving the wheels 54 at the upper end of the masts 2' is provided to permit the rolling of the device along the rail trackway 6 which is located adjacent the top of the mast 2'.

In both types of construction the lift truck 1, 1' is designed primarily as a basket type stand 7, 7' for the operator. The lift truck 1' presents on one transverse side a folding table 23 which is pivotal to permit access to the basket, and on the opposite transverse side, there is a telescoping table 24 which is displaceable crosswise to the shelf corridors. Despite the previously mentioned possibility of access from the transverse side which is also present, in the example as shown in FIGS. 4 to 6, access through a folding door 25 from the longitudinal side is provided. It is thereby made possible for the operator to leave the lift space without first having to clear the folding table 23.

The shelf handling device described offers, besides the fully explained advantages of the selected lift truck design, the substantial advantage that it can be produced similar to a modular constructional system so as to be operable for movement on a trackway defined on the floor or along a trackway at the upper end of the mast or can be converted subsequently from one model to the other.

Claims

What is claimed is:

1. In a shelf handling device of the type including a mast formed by at least one upright vertically extending member, a truck movable upwardly and downwardly along the mast, and means for moving the mast with the truck along a trackway: an improved truck comprising, in combination, four vertical columns arranged at the corners of a substantially rectangular stand portion, and including two columns on the side toward said mast interconnected by a first longitudinal beam and two columns on the side remote from said mast interconnected by a second longitudinal beam; said first longitudinal beam interconnecting its associated columns at points spaced substantially from their upper ends, and said second longitudinal beam interconnecting the bottom ends of its associated columns; at least one transverse beam interconnecting said first and second longitudinal beams; an operator's stand supported on said transverse beams; load receiving means carried on said columns; and at least one access door for the operator on said stand portion; the upper ends of said columns being free of interconnection to each other; whereby said stand portion is open and unobstructed above said operator's platform at both opposite ends and on its side remote from said mast, whereby said load receiving means may be mounted at any selected location with respect to said operator's stand.

2. A shelf handling device, according to claim 1, wherein said first longitudinal beam is a traverse type, and wherein said longitudinal beams are interconnected by at least one additional transverse beam.

3. A shelf handling device, according to claim 1, wherein said transverse beams are L-shaped.

4. A shelf handling device, according to claim 1, wherein said longitudinal and transverse beams are dimensioned in respect to strength to accommodate the highest moment to be received by said corner columns.

5. A shelf handling device, according to claim 1, including a trackway defined along the floor, and said means for moving said device along said trackway includes roller means engageable with said trackway.

6. A shelf handling device, according to claim 1, wherein said means for moving said device along a trackway includes an overhead trackway and drive means at the top of said mast engageable with said trackway for moving said device.

7. A shelf handling device, according to claim 1, wherein said transverse beams are L-shaped, and an operator's platform mounted on said transverse beams.