GB2252096A

GB2252096A - Handling device

Info

Publication number: GB2252096A
Application number: GB9200060A
Authority: GB
Inventors: Yoji Tsuboi; Setsuo Azuma
Original assignee: Okura Yusoki KK
Current assignee: Okura Yusoki KK
Priority date: 1991-01-14
Filing date: 1992-01-03
Publication date: 1992-07-29
Anticipated expiration: 2012-01-03
Also published as: GB2252096B; JPH04235899A; GB9200060D0

Abstract

A main frame 8 is installed on rails 7, and is provided with elevating frame 18. Ten pairs of forks 26, 27, project from elevating frame 18. The forks are able to move together laterally and the group of five pairs of forks 27 at the left side are laterally movable towards and away from the group of five pairs of forks 28 at the right side. By means of laterally moving all the forks 26 and 27 and laterally moving the five pairs of forks 27 at the left side, forks 26 and 27 are respectively positioned to correspond to openings Pa of pallets P aligned on conveyors 2. Forks 26 and 27 are advanced and inserted into pallets P, and then elevated to lift pallets P to a loading bay (1) for loading a truck (T). <IMAGE>

Description

Loading Device The present invention relates to a loading device for moving a plurality of pallets arranged in side-by-side relation. A particular application of the invention is to a cargo handling system comprising a loading bay, at least one conveyor arranged parallel to the loading bay and a device for moving a plurality of pallets arranged in side-by-side relation between the conveyor(s) and the loading bay where a truck is waiting to receive or discharge the pallets Examples of convention truck cargo handling devices include those disclosed in Japanese Patent Publication No. 19675/1973 and Japanese Utility Model Publication Laid-Open No. 41134/1986.

Although the above conventional truck cargo handling devices differ in that one is a high suspension type while the other is a ground travelling type. They are common in that spaces between a plurality of forks which are installed to scoop a plurality of pallets at once are fixed, in accordance with pallets arranged closely adjacent to each other.

As described above, in case of convention truck cargo handling devices, spaces between a plurality of forks are fixed in accordance with pallets arranged closely adjacent to each other. Therefore, if the pallets are not arranged close to each other but have space in between them because of overhanging cargo it is sometimes impossible to insert all the forks into the pallets.

In order to solve the above problems the present invention has as its objective the provision of a handling device which is capable of coping with changes in the spacing of pallets.

According to the first aspect of the present invention a loading device for moving a plurality of pallets arranged in side-by-side relation between a first position and a second position comprises: a main frame movable in the direction between said positions; an elevating frame supported from the main frame and movable vertically with respect to the main frame; a plurality of pairs of forks projecting in sideby-side relation from the front of said elevating frame, each pair of forks being arranged to engage and support a pallet and wherein at least some of the pairs of forks are movable in the lateral direction and that spaces between at least some of the pairs of forks are adjustable.

According to a second aspect of the invention a cargo handling system comprises a loading bay, at least one conveyor arranged parallel to the loading bay and to one side thereof and a loading device for moving a plurality of pallets arranged in side-by-side relation between the loading bay and the conveyor(s), said device comprising a main frame movable in the direction between said conveyors and said loading bay, an elevating frame supported from the main frame and movable vertically with respect to the main frame and a plurality of pairs of forks projecting in sideby-side relation from the front of said elevating frame, each pair of forks being arranged to engage and support a pallet and wherein at least some of the pairs of forks are movable in the lateral direction and that spaces between at least some of the pairs of forks are adjustable.

The above and other objects, features and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings, in which like reference numerals designate the same elements.

Figure 1 is a top view of an embodiment of a loading system for cargo according to the present invention; Figure 2 is a front view of the loading device; Figure 3 is a side view of the loading system; and Figure 4 is an explanatory figure to illustrate the adjusting of spaces between forks of the loading device.

An embodiment of a cargo loading device according to the present invention is explained hereunder, referring to the drawings.

In Figures 1 through 3, numeral 1 denotes a loading bay for a truck T. Adjacent to one side of a loading bay 1, there are a pair of conveyors 2 installed in parallel side-by-side relation. A pair of conveyors 3, similarly in parallel side-by-side relation, are installed at one end of the said pair of conveyors 2 so as to be aligned with them. The adjacent ends of the conveyors 2, 3, are spaced apart but can be bridged by a pair of conveyors 4 which are pivoted to the conveyors 3. A plurality of pallets P loaded with cargo W are sequentially carried from each conveyor 3 over the connecting conveyor 4 to each conveyor 2, and then stopped on conveyor 2 by a stopper or a similar device (not shown in the drawings). Thus up to 10 pallets can be arranged on each of the two conveyors 2.

A pair of rails 7 are provided on the floor and extend from the far side of conveyors 2 towards the loading bay 1. The rails 7 pass the respective opposite ends of conveyors 2. A main frame 8 is movably supported on the pair of rails 7 by a plurality of wheels 9. The main frame has an approximately U shaped opening at the front, i.e. the end facing the conveyors 2. Thus, by driving some of the wheels 9, the frame 8 moves along the pair of rails 7 in the direction towards or away from the loading bay 1.

A pair of frames 12 are pivotally supported at the opposite front corners of frame 8. The frames are pivotable about shafts 13 and can be pivoted forward and rearward from their respective vertical positions, by means of synchronised operation of a pair of hydraulic cylinders (not shown) through respective rods 14, the hydraulic cylinders being mounted on both sides of the upper part of frame 8.

A coupling beam 15 is attached between the upper ends of the frames 12.

Between frames 12 an elevating frame 18, in the form of a horizontal bar, is so supported as to be able to move vertically with respect to frames 12. Whilst maintaining its horizontal state, elevating frame 18 is raised and lowered by chains 20 by means of synchronised operation of a pair of hydraulic cylinders 19 respectively mounted on the outside of the pair of frames 12.

The left half of Figure 2 shows elevating frame 18 in its lowered state, while the right half shows same in its elevated state.

A plurality of slide frame 23 (10 in the case of the present embodiment) are so supported at the front of elevating frame 18 as to be movable in the lateral direction along the elevating frame. The group of five slide frames 23 at the left hand side of the elevating frame are connected in equal spaced relation by connecting rod 25 and the group of five slide frames at the right hand side of the frame connected are in equal spaced relation by connecting rod 24.

A pair of forks 26 project horizontally from the bottom front portion of each one of the right end group of slide frames 23 with equal space between the forks, and a pair of forms 27 project horizontally from the bottom front portion of each one of the five left end group of slide frames 23 with equal space between the forks. Out of the total of ten pairs of forks 26 and 27, forks 27 are able to be rotated upward when they are not needed by means of hydraulic cylinders 28 respectively mounted on slide frames 23.

Connecting rod 24 that connects the right end group of slide frames 23 is laterally movable along elevating frame 18 by means of a hydraulic cylinder 31 mounted on elevating frame 18. The adjacent slide frames of the two groups are connected by hydraulic cylinder 32, by means of which the left end group of five slide frames 23 are laterally moved along elevating frame 18, towards or away from the right end group of five slide frames 23. In other words, the ten pairs of forks 26 and 27 are laterally moved together by means of hydraulic cylinder 31, and the left end group of forks 27 are laterally moved in a body towards or away from the right end pairs of forks 26 by means of hydraulic cylinder 32.

Next, the operation of the device will be explained.

Pallets P loaded with cargo W are conveyed from the conveyors 3 through connecting conveyors 4, onto conveyors 2.

When a specified number of pallets P (for example, 10 for each row in a total of 20 pallets) have been lined up in two rows on conveyors 2, transportation of subsequent pallets P is stopped, and connecting conveyors 4 are raised from their horizontal position in order to be spaced from conveyors 2.

Under the above condition, respective positions of the ten pairs of forks 26 and 27 are adjusted in relation to the openings of aligned pallets P, which consist of two rows of, ten pallets, by laterally moving the ten pairs of forks 26 and 27 in a body by using hydraulic cylinder 31 and/or laterally moving the left five pairs of forks 27 in a body towards or away from the right five pairs of forks 26 by using hydraulic cylinder 32.

There is a difference in position of opening Pa of pallets P between cases shown in the lower half of Figure 4 that shows the pallets and forks upside down, wherein cargo W does not overhand each pallet P so that pallets P are aligned adjacently to each other, and cases shown in the upper half of Figure 4 wherein cargo W overhangs each pallet P so that pallets P are aligned with space between each other. Should this differential be accumulated, opening Pa of pallets P may deviate too much for some of forks 26 and 27 to be inserted. The adjustment of the position described above is conducted in order to prevent this problem.

More precisely, in cases where pallets P are aligned adjacently to each other as shown in the lower half of Figure 4, ten pairs of forks 26 and 27 are moved collectively by hydraulic cylinder 31 to the position where fork 26 at the right end as it is shown in Figure 4 can be inserted into the right end of the inside of opening Pa of the pallet facing the said fork, i.e. pallet P at the right end, and five pairs of forks 27 at the left side are moved collectively towards five pairs of forks 26 at the right side by hydraulic cylinder 32 to the position where fork 27 at the left end as it is shown in Figure 4 can be inserted into the left end of the inside of opening Pa of the pallet facing the said fork, i.e. pallet P at the left end. A s a result, each and every fork 26 or 27 is positioned within a usable range of opening Pa of corresponding pallet P.In other words, every fork can be inserted into opening Pa of pallet P facing it.

Then, frame 8 is moved forward in order to insert ten pairs of forks 26 and 27, which are positioned in their horizontal state, into respective openings Pa of ten pairs of pallets P.

Then, by raising elevating frame 18, each pallet P is lifted by its corresponding pair of forks 26 and 27. The support of pallets P by forks 26 and 27 is stabilised by rotating the pair of frames 12 a little rearward around shafts 13, thereby inclining forks 26 and 27 somewhat upward from their horizontal position.

Next, frame 8 is moved forward again in order to move pallets P respectively supported by forks 26 and 27 above rear body Ta of truck T at loading bay.

Then, the ten pairs of forks 26 and 27 are moved all together to the right by means of hydraulic cylinder 31, and pallet P at the right end is moved to the forefront of rear body Ta of truck T.

Then, by lowering elevating frame 18, each pallet P is placed on rear body Ta of truck T, while forks 26 and 27 are returned to their horizontal position by rotating the pair of frames 12 a little forward around shafts 13.

Next, by moving frame 8 rearward, forks 26 and 27 are removed from pallets P and returned to their original position.

Then, elevating frame 18 is lowered to its original position, while the ten pairs of forks 26 and 27 are collectively moved leftward by hydraulic cylinder 31 to their original position.

When loading cargo on Truck T in such a manner described above, in cases where rear body Ta of truck t is short and the number of pallets P in each row for loading is therefore less than ten (however, there must be at least five per row in case of the present embodiment), it is possible to move the left end group of forks 27 out of the way by rotating them upward, using hydraulic cylinders 28 mounted on slide frames 23. Therefore, should truck T be equipped with a flap of the gull-wing type, there is no danger of unwanted forks 27 colliding with a supporting post of the flat at the rear end of rear body Ta.

In case of the present embodiment, the device is configurated in such a manner that the left end group of forks 27 are collectively moved in the lateral direction towards or away from the right end group of forks 26 in order to cope with changes in the spacing of pallets P.

However, application of the present invention is not limited to this configuration; it is also possible to adjust all the spaces between adjacent slide frames 23, each of which is provided with a pair of forks 26 or 27.

Although the above explanation concerns cases where pallets P are transported from conveyors 2 onto the rear body Ta of truck T, the present invention may also be applicable to the transport of pallets P from the rear body Ta of truck T onto conveyors or from between any two positions.

As described above, advice for handling truck cargo according to the present invention, which loads and unloads a plurality of pallets loaded with cargo onto and off of a truck and conveyors by means of a plurality of forks, is capable of adjusting spaces between the forks.

Therefore, regardless of changes in the spacing of pallets, it is possible to insert all forks into respective pallets without fail.

Having described preferred embodiments of the invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope of the invention as defined in the appended claims.

Claims

CLAIMS:

1. A loading device for moving a plurality of pallets arranged in side-by-side relation between a first position and a second position comprising: a main frame movable in the direction between said positions; an elevating frame supported from the main frame and movable vertically with respect to the main frame; a plurality of pairs of forks projecting in sideby-side relation from the front of said elevating frame, each pair of forks being arranged to engage and support a pallet and wherein at least some of the pairs of forks are movable in the lateral direction and that spaces between at least some of the pairs of forks are adjustable.

2. A device as claimed in claim 1, in which the pairs of forks are arranged in two groups and the forks of one group are displaceable laterally with respect to the forks of the other group to adjust the spacing between the two groups.

3. A device as claimed in claim 1, in which at least some of the pairs of forks are rotatable upwardly with respect to the elevating frame.

4. A device as claimed in claim 3 in which the pairs of forks are arranged in two groups and the pairs of forks in one group are rotatable upwardly with respect to the elevating frame.

5. A device as claimed in any preceding claim, in which the main frame has wheels which enable it to be moved along rails.

6. A device as claimed in any preceding claim in which each pair of forks is capable of engaging and supporting two pallets arranged one behind the other.

7. A loading device for moving a plurality of pallets arranged in side-by-side relation between a first position and a second position substantially as hereinbefore described with reference to the accompanying drawings.

8. A cargo handling system comprising a loading bay, at least one conveyor arranged parallel to the loading bay and to one side thereof and a loading device as claimed in any preceding claim for moving a plurality of pallets arranged in side-by-side relation between the conveyor(s) and the loading bay.