Container Random Access Storage System

Abstract

A three-dimensional multi-tier, open frame, structure defining spaces or cells for receiving modular shipping containers is arranged with a movable cradle in each cell for holding the container. Each cradle can be moved horizontally one cell width so that a particular container stored within the structure is accessible to a crane from above.

Description

BACKGROUND OF THE INVENTION

This invention relates to containerized cargo systems and more particularly to methods of storing containerized cargo.

The conventional method of storing modular containers containing cargo while in transit at distribution points where space is at a premium is to stack one container on top of another. To reach a particular container in the pile requires the removal by a crane of the upper containers which must be restacked in another location before the particular container can be removed.

Container ships must be loaded in a sequence which is dictated by Port of Destination sequence and balanced ship loading to avoid whipping and excessive ship roll action and assure safe handling of the vessel.

The stacking, restacking and double and triple handling of containers to load a ship in a particular sequence is time consuming and thus expensive.

Although pre-storage systems have been developed, they are, in fact, operationally unrealistic since the containers are not delivered to the distribution point according to any fixed schedule.

SUMMARY OF THE INVENTION

The apparatus of the present invention permits the three-dimensional storage of modular containers in a random manner while permitting access to individual containers without multiple handling of the other containers in the stack, by moving those containers above the particular container aside for access from above.

It is, therefore, an object of the present invention to provide a device for three-dimensional storing of modular containers.

It is another object of the present invention to provide a device for three-dimensional storing of modular containers in which any particular individual container is readily accessible.

It is also an object of the present invention to provide a device for three-dimensional storing of modular containers in which individual containers are accessible by automated means.

Other and more particular objects of this invention will be manifest upon study of the following detailed description when taken together with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view, from above, of the container storage device of the present invention showing the general configuration of the apparatus,

FIG. 2 is an isometric view, from below, showing the apparatus for moving the cradles one cell width to one side,

FIG. 3 is a sectional view taken at line 3--3 of FIG. 2,

FIG. 4 is a diagrammatric illustration of the typical arrangement of hydraulic cylinder and pistons for part of a typical tier,

FIG. 5 is a schematic diagram of part of the hydraulic system of the apparatus,

FIG. 6 is a schematic electrical diagram of part of the control system for the container storage apparatus of the present invention,

FIGS. 7A and 7B are diagrammatric elevationed views of one bay of the apparatus showing how access to a particular container is achieved, and

FIG. 8 is a block diagram of an automatic control system for the apparatus of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows the basic configuration of the modular container storage apparatus of the present invention in use.

Basically, the apparatus comprises a three-dimentional multi-tiered frame structure 11 defining open spaces or cells 12 which are adapted to receive modular cargo containers 14. Then each cargo container in a cell above ground level is supported on a cradle 15 which is also adapted to move horizontally sideways one cell width along support bracket assembly 17.

A crane 20, having a moveable hoist trolly 21, is used to raise and lower container 14 out of and into the apparatus through the use of a typical lifting spreader 22.

For reference, each cell 12 can be identified by a set of three coordinates. For the presently illustrated embodiment each tier on level beginning from the top is labelled T1, T2, T3 and T4. Each bay, beginning from the top is labelled A, B, C and D. Each row, beginning from the left, is labelled R1, R2, R3, R4 and R5.

Thus, in FIG. 1, crane 20 is lifting a container from bay B, row R3, tier T3 (hidden from view), or, in a shorter form, B-R3-T3.

The basic configuration for a filled bay is that shown for bay A of FIG. 1 in which all cells are filled except the end rows on each side above the ground level (R1-T1, R1-T2, R1-T3, R5-T1 R5-T2 and R5-T3). As will be seen, these empty spaces are necessary to permit the horizontal sideways movement of cradles 15.

To provide such movement, FIG. 2 illustrates the method and apparatus by which each cradle 15 is moved horizontally sideways one cell width.

The apparatus of FIG. 2 comprises guide channel 24 which is attached to support bracket assembly 17 (which in turn is attached to multi-tier frame structure 11 and also acts as a structural member thereof), and hydraulic motive means 23.

Channel 24 is adapted to receive load bearing wheels 25 which are journaled to shaft 26 connected to each end of cradle 15 to allow cradle 15 to roll sideways one cell width along channel 24.

Hydraulic motive means 23 provides the force necessary to move cradle 15 sideways one cell width and comprises an hydraulic cylinder 27 having a double acting piston 28 which is provided with first and second piston rods 29 and 30, respectively, which are in turn connected to cradle 15 through various sheaves in cooperation with cable 39.

With particular reference to FIG. 2 and part of FIG. 3, at the end of first piston rod 29 is connected first movable sheave 31, while at the corresponding end of second piston rod 30 is connected second movable sheave 32.

A first fixed sheave 34 is journaled to shaft 35 which is attached to support bracket assembly 17 adjacent first piston rod 29 but located at a slightly greater distance than the length of travel of rod 29 from cylinder 27.

Cable 39 is provided with one end attached to first fixed end clamp 40 which is attached to support bracket assembly 17 below first fixed sheave 34 then received through first movable sheave 31, next through first fixed sheave 34, down under guide channel 24 where it is attached to cradle bracket arms 41 with clamps 42, through second fixed sheave 36, through second movable sheave 32 and finally attached to second fixed end clamp 43 which is attached to support bracket 17 below second fixed sheave 36.

Thus it can be seen from FIG. 2 that as piston 28 moves to the right, first movable sheave 31 will travel away from first fixed sheave 34 and first fixed end clamp 40.

Since one end of cable 39 is held by clamp 40, this movement will pull cable 39 through and around sheave 34 pulling cradle 15 to the left since cable 39 is connected thereto through clamp 42 and brackets 41.

Since second movable sheave 32 is, concurrently, moving toward second fixed sheave 36 and clamp 43, so that take-up of slack in cable 39 is provided for.

When the direction of piston 28 is reversed, the direction of travel of cradle 15 is also reversed.

It can also be seen from FIG. 2 that with the present receiving system a mechanical advantage is obtained in that for every unit length of travel of piston 28, cradle 15 moves two unit lengths. In other words, for one cell width of travel by cradle 15, piston 28 travels only one-half a cell width. By adding additional movable and fixed sheaves other ratios of piston to cradle travel can be achieved.

FIG. 3 is a sectional view through support bracket assembly 17 showing the alignment of cylinder 27, sheaves 31 and 32 and cable 39. As will be apparent in FIG. 4 for overlapping cable systems, the next adjacent system (not shown) must be offset from bracket 17 and attached to bracket 41 at a point closer to cradle 15 to prevent interference with each neighboring system.

It will also be noted in FIG. 3 that as hydraulic motive means 23 pulls cradle 15, unequal forces may be exerted on the ends of cradle 15. To prevent jamming in channel 24, stabilizing wheels 44 are provided which are journalled to shaft 45 which is attached to cradle 15.

With respect to FIG. 4, illustrated is a diagrammatric elevational view of a typical tier of one bay showing the overlapping of the individual hydraulic cylinder-piston-cable systems.

In FIG. 4, a lower case letters is used after the reference numeral to distinguish those elements which are used to move a cradle in each row. The reference numerals themselves correspond to the reference numerals used in FIGS. 2 and 3 to identify that corresponding element of the apparatus for moving cradle 15.

For example, hydraulic cylinder 17 is used to move cradle 15a containing cargo container 14a and comprises cable 39a which is attached at one end to support bracket assembly 17 by first fixed end clamp 40a, and is reeved through first movable sheave 31a, then through first fixed sheave 34a, then attached to cradle 15a by clamps 42a, then through second fixed sheave 36a, through second movable sheave 32a and finally attached to support bracket assembly 17 by second fixed end clamp 43a.

In the next row to the left, hydraulic cylinder 27b is used to move cradle 15b containing cargo container 14b and comprises cable 39b, which is attached at one end to support bracket assembly 17 by first fixed end clamp 40b, and is then reeved through first movable sheave 31b, then through first fixed sheaves 34'b and 34b, then attached to cradle 15b by clamps 42b, then through second fixed sheaves 36b and 36'b, through second movable sheave 32b and finally attached to support bracket assembly 17 by second fixed clamp 43b.

It will be noted that two pair of fixed sheaves 34'b-34b and 36'b-36b are used in the last example because of the overlapping of cables 39 with neighboring systems.

Cable 39b must be set off, i.e., spaced apart from support bracket assembly 17 a slightly greater distance than cable 39a to allow for clearance. Also, the alignment of cylinders 27b and its associated sheaves must also be spaced from bracket 17 to allow for such clearance.

With reference to FIG. 5, there is illustrated a schematic diagram of a part of the hydraulic system of the present invention showing two typical hydraulic cylinders, for moving cradle 15, one cylinder for row R4, tier T1, which is in the activated state, and one cylinder for row R4, tier T3, which is in the inactivated or normal state.

FIG. 6 is an electrical circuit diagram for row R3 of a typical bay, in the present case, bay B, to coordinate the illustration with FIGS. 1, 5, 7A and 7B.

With reference to FIG. 5, basically the hydraulic system of the present invention comprises a pump 51 for creating the hydraulic pressure and pumping the hydraulic fluid through pipes 52 in the direction as indicated by arrow 53, an accummulator 54 to absorb any hydraulic fluid pressure surges and maintains a steady fluid pressure, and multiple port, spring return, solenoid valves 55 at each hydraulic cylinder 27.

Each solenoid valve is equipped with an electrical solenoid coil 57, a plunger 58 having its longitudinal axis coincident with that of coil 57 and a spring return arranged to opposing movement of plunger 58 into coil 57.

When coil 57 is not energized, the flow of hydraulic fluid through the valve is that shown for SOL R4-T3 as indicated by arrows 61. Piston 28 is positioned at the right end of cylinder 27, since the pressure of hydraulic fluid is greater on the left side of the piston.

When coil 57 is energized or activated, the flow of hydraulic fluid through the valve is that shown for valve 55' or SOL R3-T1 as shown by arrows 61'. Piston 28' is positioned at the left end of cylinder 27' since now the pressure of hydraulic fluid is greater on the right side of the piston. Also, plunger 58' is now drawn into energized coil 57' compressing spring 59'.

The typical circuit for selecting access to a particular container is shown in FIG. 6 in which a typical graphic control panel 63, illustrating one bay (Bay B in the present example), comprising a plurality of momentary contact push buttons switches 64 arranged in ordered array which are used to control the operation of solenoid valves 55 and a normally closed "return" push button switch 65 which returns all solenoid valves 55 to their original or normal (inactivated) position.

Generally, the control system of the present apparatus comprises power source 67 used to provide electrical energy to the system, multiple contact, normally open, relays 66 and control panel 63.

The negative side of power source 67 has been treated as the common side of the electrical system with the positive side of power source 67 being treated as the switched side.

Normally closed push button switch 65 in panel 63 has been connected so that when depressed, all power to relays 66 and coils 57 of solenoid valve 55 is disconnected.

It will be noted also that each relay 66 has been provided with an extra set of contacts 71 connected in parallel with its corresponding control panel push button switch to maintain relay 66 closed when the push button is released.

OPERATION

A typical bay, such as Bay B, when filled to capacity, is as shown graphically in FIG. 7A. All five rows of tier 4 are filled with all tiers filled except those for rows R-1 and R-5 above the ground level.

To obtain access to a particular container, for example, the one located at R3-T3, an operator depresses push button 64 on control panel 63 corresponding to location R3-T3, (FIG. 6), thus closing contacts 69.

An electrical current is thus permitted to flow from power source 67, through the normally closed contacts of "return" push button 65 to one side of relay 66 for R3-T3. Since the other side of relay 66 for R3-T3 is connected to the other side of power source 67, the relay will close as shown in FIG. 6. Since contacts 71 of relay 66 for relay R3-T3 are also connected to power source 67 in parallel with push button 64, the relay will remain energized when push button 64 for R3-T3 is released. At the same time, electrical current flows to coil 57 of solenoid valves 55 through contacts 70 of relay R3-T3 to energize coil 57 of solenoid valve 55 for SOL R3-T1, SOL R4-T1, SOL R3-T2 and SOL R4-T2 causing the corresponding cradles 15 for each of those locations to move one cell width to the right as shown in FIG. 7B. Now, lifting trolley 21, located above cell R3-T3, can lower its lifting spreader 22 down to the container in that cell for attachment and removal of the container.

After removing the container, "return" push button 65 is depressed by the operator to disconnect all power to relays 66 and solenoid valves 55 thus permitting them to return to their normal positions.

In a similar manner, if access were desired to cell R2-T3, the cradles in cells R2-T1 and R2-T2 would be moved to the left one cell width to row R-1, and then returned to their original position after access was achieved.

For small installations, only one row above the ground level need be left open into which cradles may be moved since the power requirements for movement would be small. In large installation, spaces on each side may prove more desirable in that, at most, only one half of the containers above the deepest one in the stack would have to be moved.

The apparatus of the present invention can also be adapted for automatic control as shown in FIG. 8 which illustrates a block diagram of a typical control system.

A sequence selector 74 is arranged so that an operator can select either the sequence he wishes the containers to be placed in particular cells or the sequence he wishes containers to be removed from the cells.

Sequence selector 74 is connected to a control unit 75 which also contains a memory as to filled or unfilled cells and translates the information from the sequence selector to the three coordinate system as previously described, then conveys the information as to "bay" location to crane position control 76, "row" location to trolley position control 77, and "tier" location to lifting spreader position control 78, concurrently with instructing cradle position control 79 as to which cradles to move one cell width sideways for access to the cell location.

The following tabulation is an illustration of the time required to retrieve a container from the storage device of the present invention for a crane travel velocity of 150 FPM (feet per minute), trolley travel velocity of 400 FPM and hoist velocity of 150 FPM.

sequence Components Function Time (Secs.) 1 Crane Travel to designated bay 30 2 Spreader Lower to container on vehicle 5 3 Spreader Locks onto container 2 4 Spreader Lifts container 5 5 Trolley Travel horizontally 5 6 Spreader Lowers container in cell 5 7 Spreader Unlocks container 2 8 Spreader Lifts from container 5 9 Crane Travel to designated bay 30 10 Spreader Lower to container 5 11 Spreader Locks onto container 2 12 Spreader Lifts container 5 13 Trolley Travels horizontally 5 14 Spreader Lowers container to vehicle 5 15 Spreader Unlocks container 2 16 Spreader Lifts from container 5 118 seconds

Total time to complete one cycle = 1.97 min.

Thus, using the apparatus of the present invention, more rapid and efficient handling of cargo containers is achieved.

Claims

I claim:

1. An apparatus for storing modular containers comprising

a multiple tier frame structure defining a plurality of cells adapted to receive a modular container, each cell accessable from the top of the structure,

cradles in said cells adapted to support a modular container and to move horizontally one cell width,

an hydraulic cylinder connected to said frame structure,

a piston slidably disposed in said hydraulic cylinder,

means for providing pressurized hydraulic fluid to said cylinder, and

means connected to said piston for moving said cradle one cell width for a movement of said piston of a distance of less than one cell width.

2. The apparatus for storing modular containers as claimed in claim 1 wherein said means for moving said cradle comprises a double acting piston contained in said cylinder, a first and second movable sheave attached to opposite ends of said piston, a first and second fixed sheave attached to said frame structure at opposite ends of said piston and disposed a distance equal to or greater than the length of piston travel from the end of said cylinder and cable having a first end attached to said frame structure adjacent said first fixed sheave and a second end attached to said frame structure adjacent said second fixed sheave and said cable from said first fixed end reeved through said first movable sheave, then through said first fixed sheave, then through said second fixed sheave, then through said second movable sheave to said second fixed end, with said cradle attached to said cable between said first and second fixed sheaves.