Automatic warehouse

Abstract

To provide a device for earthquake countermeasures in existing automatic warehouses, which can be installed at a low cost and has a control system independent of existing control systems.SOLUTION: There is provided a device for earthquake countermeasures in existing automatic warehouses, in which the device realizes a falling prevention function requiring no separate external power by disposing a falling prevention fence for preventing an article on a pallet from falling when an earthquake occurs and interlocking an opening / closing mechanism of the falling prevention fence with the vertical movement of the pallet.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention is an automated warehouse having a mechanism for preventing items on a pallet from falling due to a collapse of the load caused by an earthquake or the like, which operates when the pallet is placed on a storage shelf. [Background technology]

[0002] In large-scale automated warehouses, the storage shelves are arranged high and three-dimensionally, so if items on pallets fall during an earthquake, the entire automated warehouse will stop functioning, and in some cases it may take several months to restore operation. As a means to prevent this, some automated warehouses incorporate vibration isolation or seismic isolation structures for the entire storage shelves of the warehouse, but this increases the scale and equipment costs, and it is almost impossible to install vibration isolation or seismic isolation devices later in existing automated warehouses. For this reason, there is a strong demand for a means to prevent items stored on pallets from collapsing and falling due to earthquake shaking. There is also a demand for devices that function even during power outages, which are likely to occur during earthquakes, and devices that can be installed later in existing automated warehouses. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 8-29809 [Patent Document 2] Japanese Patent Application Publication No. 10-218180 [Patent Document 3] JP 2003-300608 A [Patent Document 4] Publication number 1-152906 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional earthquake countermeasures for automated warehouses involve the use of vibration isolation and seismic isolation structures for the entire warehouse storage shelves to prevent items on pallets from shaking and falling. However, adopting these vibration control and seismic isolation devices increases the cost of the warehouse, and the vibration isolation and seismic isolation devices also worsen the space factor, which can impair the functionality of the automated warehouse. Furthermore, all of the prior art patent documents provide measures to prevent the pallet from falling alone, and do not provide any function for preventing the individual items placed on the pallet from falling.

[0005] Furthermore, most existing automated warehouses do not have the vibration and seismic isolation structures mentioned above, so these will have to be installed later. In most cases, however, the existing storage shelves cannot be used and all of them will have to be replaced. [Means for solving the problem]

[0006] The present invention has been devised in consideration of the above circumstances, and its purpose is to provide earthquake countermeasures for existing automated warehouses that are not earthquake-proof, and also to provide a method for implementing earthquake countermeasures for newly constructed automated warehouses more simply and at lower cost than before.

[0007] Installing fences to prevent items from falling in a conventional automated warehouse requires a large-scale installation, including a drive for opening and closing the fence, a mechanical transmission mechanism, electrical circuits to operate these, a controller to control them, and new sensors to detect the position of the pallets.

[0008] In addition, because it must be linked to the automated warehouse's original control mechanism and controller, it is necessary to make new modifications to the original control program, which requires a huge development time and cost.

[0009] Considering these points, the gist of the present invention is that no external power is used, no modifications are made to the current controller or control functions, no position control of the pallet is performed, no electrical components are used, etc. Therefore, in the present invention, the driving force for opening and closing the fall prevention fence is the vertical movement of the pallet, and the vertical movement is linked to the opening and closing of the fall prevention fence. In the procedure for installing the pallet on the storage shelf, the slide fork or slide table (hereinafter referred to as the slide fork) on the carriage carrying the pallet stops at a position slightly higher than the installation height of the storage shelf, and the slide fork is inserted into the storage shelf. When the pallet is directly above the installation location of the storage shelf, the carriage lowers, the pallet rests on the ground surface of the storage shelf, the carriage lowers further, and when the installation of the pallet on the storage shelf is completed, the slide fork is stored in the carriage. Usually, the height when the slide fork moves back and forth is about 10 cm higher than the height when the pallet is installed on the storage shelf, and this height difference becomes the driving force for opening and closing the fall prevention fence.

[0010] The driving force for the up and down movement of the pallet is a mechanism in which a pedal is set on the surface of the pallet, and when the pallet is placed, the pedal is pressed, and the movement of the pedal is transmitted to the opening and closing of the fall prevention fence using a wire. The movement of the wire links the movement of the pedal to the opening and closing of the fall prevention fence. Since the wire transmits power only in the pulling direction, when used to open and close a fall prevention fence, the wire is loosened when it is open, and the fence closes when the wire is pulled. Therefore, the force that returns the pedal upwards is applied by the fence's own weight in the direction that the fence opens. If the fence's own weight cannot be used sufficiently, a separate weight or a spring can be used to provide the force that returns the pedal.

[0011] In this invention, the force that the pallet pushes the pedal is the weight of the pallet on which the goods are placed, so that weight must exceed the force required to close the fall prevention fence. As an example, the weight of a single pallet used in a normal automated warehouse is 10kg to 20kg, and when the weight of the goods is added, it becomes about 50kg or more. The weight of a single fall prevention fence is about 10kg, and the moment force to close the fall prevention fence is 300kg cm if the arm length of the fall prevention fence is 30cm. If the pedal moves up and down about 10cm, the moment force acting is 500kg cm if the pallet weight is 10kg, which is sufficient, but if the goods are very light, a balance weight may be attached to the arm of the fall prevention fence to reduce the downward moment force of the fall prevention fence.

[0012] However, pallets are not usually stored alone in an automated warehouse. In the case of pallets alone, or pallets carrying a small number of items, the load will not fall in the first place, so there is almost no problem in the event of an earthquake even if the safety fence does not close due to the pallet's insufficient weight.

[0013] In this invention, the pedal and fall prevention fence work in tandem, but even if they do not work together due to some abnormality, the tension transmitted between the pedal and the wire is mediated by a spring, so even if an unexpected force is applied, it will not damage the equipment. Furthermore, if any abnormality occurs, the spring will expand or contract more than the set value, and by detecting this change, it is possible to indicate the abnormality. Effect of the Invention

[0014] The present invention provides equipment that can be installed at low cost and with control independent of existing control systems, which has previously been considered difficult to implement as earthquake countermeasures for existing automated warehouses, thereby making it possible to minimize damage to automated warehouses in the event of an earthquake. Conventional fall prevention technology only prevented the pallet from falling, but the present invention makes it possible to prevent not only the items on the pallet from falling. Furthermore, because the mechanical structure is extremely simple, earthquake-proof automated warehouses can be constructed very inexpensively even for new warehouses. [Brief description of the drawings]

[0015] [Figure 1] Conceptual diagram of an automated warehouse [Diagram 2] Enlarged view of the lifting carriage (when transporting pallets) [Diagram 3] Close-up of the lifting carriage (with pallet storage installed) [Figure 4] Fall prevention fence illustration: When the fence is closed [Diagram 5] Fall prevention fence illustration: When the fence is open [Figure 6] Overall view of pedal mechanism [Figure 7] When the pedal is released [Figure 8] When the pedal is activated (pressed against the pallet) [Figure 9] When the pedal is not working properly (when the fence does not move even when pressed by the pallet) [Figure 10] When the pedal is not working properly (when the fence does not open even after being released from the pallet) [Figure 11] Wire tension abnormality detection mechanism (1 sensor 2 magnet type) [Figure 12] Wire tension abnormality detection mechanism (2 sensor 1 magnet type) [Figure 13] Wire tension abnormality detection mechanism signal line wiring diagram DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLES

[0016] The carriage 6 of a stacker crane 4 that is installed in a typical automated warehouse like the one in Figure 1 is shown in Figures 2 and 3. Figure 2 shows the state in which the slide fork 7 that delivers the pallet 3 loaded with articles is delivering the pallet, and Figure 3 shows the state in which the slide fork 7, stacker crane 4, or carriage 6 is moving.

[0017] In an embodiment of the present invention, as shown in Figures 4 and 5, one end of two opening / closing arms 10 is rotatably attached to frame 5 of an existing automated warehouse, and the opposite end of the arm 10 is rotatably attached to a fall prevention fence 9. Similarly, two arms 10 and a fall prevention fence 9 are attached to the frame on the opposite side. Figure 4 shows a state where there is no pallet 3 or where the pallet 3 is at the height it was at when it was transported before installation, and there is no contact between the pedal 8 and the pallet 3. Figure 5 shows a state where the pallet 3 is installed on a storage shelf, and the pedal 8 is pressed by the pallet.

[0018] As shown in Figure 6, the pedal part consists of a pedal 13, a wire arm 14 integrated with the pedal, a rod housing 15 connected to the wire arm 14, a wire rod 16 which pulls the wire 11 housed in the rod housing 15, the wire 11 being connected to the wire rod and the other end of the wire 11 being connected to the arm 10. A spring 19 located between the rod housing 15 and the wire rod 16 constitutes the transmission of force and drive, and a shaft 22 of the pedal 13 is fixed to the bottom part of the automated warehouse via a bearing 23.

[0019] When the pedal 13 is pressed by the pallet 3, the wire 11 is pulled via the above-mentioned components. The wire 11 rotates the fall prevention fence opening / closing arm 10, which is connected by the wire outer 21, and closes the fall prevention fence 9. The tension required for the wire 11 to rotate the fall prevention fence opening / closing arm 10 is the downward moment force due to the weight of the fall prevention fence 9 and the arm 10, and when the fall prevention fence 9 is in the open position, the tension is small, and when the fall prevention fence 9 is in the closed position, the tension increases and the length of the spring 19 shortens slightly. This change in the length of the spring 19 is used to detect operational abnormalities, which will be described later.

[0020] An explanation of detecting normal or abnormal operation based on the change in length of the spring 19 is shown in Figs. Figures 7 and 8 show normal operation, and in Figure 7, when the pallet is not placed and the rack is open, the pedal 13 is stopped at the top by a stopper (not shown) and the fall prevention fence 9 is also open, but the length of the wire 11 is adjusted so that the fence 9 is slightly weighted and tension remains in the wire 11. The length of the spring 19 at this time is slightly shorter than the natural length of the spring (L1). The pedal 13 is stopped by the aforementioned stopper due to the tension of the wire 11.

[0021] Figure 8 shows the state where the pedal is pressed on the pallet 3. In normal operation, the weight of the fall prevention fence 9 on the wire 11 becomes large, the tension of the wire 11 increases, and the length of the spring 19 becomes slightly shorter than in the state shown in Figure 7. (L2)

[0022] Figures 9 and 10 show a state in which some abnormality occurs during operation. Figure 9 shows a case in which the wire 11 does not move even when the pedal 13 is pressed by the pallet 3, and the fall prevention fence 9 does not close normally. At this time, the spring 19 further compresses (L4).

[0023] FIG. 10 shows that even if the pedal 13 is released, the fall prevention fence 9 does not return to the open state completely due to some abnormality, and the spring returns to almost its natural length (L3).

[0024] We will now explain the mechanism that can determine whether the opening and closing function of the fall prevention fence 9 is operating normally or whether an abnormality has occurred based on the change in the length of the spring 19. Two methods are considered: one in which two permanent magnets 17 are placed on the rod 16 and one magnetic reed switch 18 is placed in the rod housing as a sensor, as shown in Figure 11, and the other in which one permanent magnet 17 is placed on the rod 16 and two magnetic reed switches 18 are placed in the rod housing as sensors, as shown in Figure 12. The former requires only one signal line, but cannot determine what type of abnormality has occurred. The latter requires two signal lines, but makes it possible to determine whether an abnormality has occurred when the fall prevention fence 9 is closing or when it has returned to the open position.

[0025] In the case of Figure 11, in normal operation the magnetic reed switch 18 moves back and forth between the two permanent magnets 17 and does not activate the magnetic reed switch 18. If the tension of the wire 11 exceeds the normal range, the magnetic reed switch 18 activates to notify of an operational abnormality.

[0026] Also, in the case of Figure 12, in normal operation, the permanent magnet 17 moves back and forth between the two magnetic reed switches 18, and neither of the magnetic reed switches 18 is activated. When the left magnetic reed switch 18a is activated, the spring 19 is excessively compressed, indicating that an abnormality has occurred when the fall prevention fence 9 is closing. When the right magnetic reed switch 18b is activated, the spring 19 is at almost its natural length, indicating that an abnormality has occurred when the fall prevention fence 9 is opening.

[0027] A schematic diagram of the operation monitoring circuit is shown in Figure 13. The signal line connects in series the magnetic reed switches 18 of the device of the present invention installed in multiple storage shelves. If any one of the magnetic reed switches becomes open, indicating an abnormality, the signal line becomes open and the open circuit detector is activated to notify the abnormality.

[0028] When two magnetic reed switches 18 are installed as in Figure 12, each magnetic reed switch 18 is connected in series to form two signal lines. Each can identify whether there is an abnormality when closing the fall prevention fence or when opening the fall prevention fence. [Explanation of symbols]

[0029] 1. Conceptual diagram of an automated warehouse 2 Stacker crane movement rails 3. Pallets and items on pallets 4 Stacker Crane 5 Automatic warehouse frame 6 Pallet Transport Carriage 7 Slide fork for pallet loading and unloading 7a Slide fork extended 7b Slide fork retracted state 8. Fall prevention fence opening / closing pedal 9. Fall prevention fence 10. Fence opening and closing arm 11 Fall prevention fence opening and closing wire 12 Rotating lever part 13 Pedals 14 Wire Arm 15 Rod housing 16 Wire Rod 17 Rod position detection magnet 17a Rod position detection magnet High tension side 17b Magnet for detecting rod position Low tension side 18 Magnetic Reed Switch 18a Magnetic Reed Switch High Tension Side 18b Magnetic reed switch low tension side 19 Outer rod connecting spring 21 Wire Outer 22 Bearings 23 Pedal shaft L Spring length L1 Spring length when the fall prevention fence is open L2 Spring length when the fall prevention fence is closed L3 The length of the spring when the fall prevention fence cannot be opened L4 The length of the spring when there is a problem closing the fall prevention fence

Claims

1. This automated warehouse has an item storage shelf with storage sections arranged in multiple vertical levels and multiple horizontal rows for storing items placed on pallets, and a stacker crane that travels along a travel path installed in front of the storage shelf, and a fall prevention fence is provided to prevent items on the pallets on the item storage shelf from collapsing and falling off the shelf in the event of an earthquake, and the fall prevention fence is provided with a mechanism that opens and closes in response to the up and down movement of the pallets positioned on the storage shelf.

2. The automated warehouse of claim 1, having a mechanism in which the fall prevention fence is attached parallel to the vertical frame of the automated warehouse by two upper and lower arms for inserting and removing the fall prevention fence, the arm and the frame, and the arm and the fall prevention fence each have a degree of rotational freedom, and when opened, the arm rotates downward due to the weight of the fall prevention fence and arm, and the fall prevention fence is stored on the frame side, and when a pallet carrying articles is placed on the storage shelf, the arm becomes nearly horizontal in conjunction with the movement of the pallet, and the fall prevention fence extends to prevent articles from falling.

3. An automated warehouse as claimed in claim 1 or 2, further comprising a mechanism in which a pedal that comes into contact with the bottom surface of the pallet is installed on the storage shelf to facilitate the opening and closing operation of the fall prevention fence, the pedal being positioned upward when there is no pallet or when the pallet is at the height of the pallet when it is being put into or taken out of the storage shelf, and when the pallet is placed on the storage shelf, the pedal is pushed downward by the pallet, thereby closing the fall prevention fence connected by a wire or the like.

4. 4. The automated warehouse according to claim 3, further comprising a mechanism in which the pedal is fixed to the bottom surface of the article shelf via a bearing on a rotating shaft, an arm for pulling a wire is fixed to the shaft on the opposite side of the pedal, the arm being integrated with the pedal, and when the pedal is pressed down, the arm rotates to close the fall prevention fence via the wire at the tip of the arm.

5. 5. The automated warehouse according to claim 4, wherein the wire is not directly attached to the arm, but is attached to a rod, the rod is in a housing connected to the arm, the rod is movable in the housing in the direction of the wire, the rod and the housing are connected via a coil spring, and tension acting on the wire is transmitted through the coil spring to close the fall prevention fence.

6. 6. The automated warehouse according to claim 5, wherein the length of the coil spring changes according to the tension of the wire, and the system is provided with an operation confirmation function that notifies an abnormality when the length of the coil spring exceeds an allowable range.

7. 7. The automated warehouse of claim 6, wherein the coil spring is attached so that tension is generated in the direction in which it contracts, one reed switch is attached to the housing to detect the length of the coil spring, two permanent magnets are attached to the rod with a distance slightly greater than the amount of change in spring length during normal opening and closing operations of the fall prevention fence, the amount of contraction of the spring due to the tension of the wire caused by the weight of the fall prevention fence etc. is length L1 when the fall prevention fence is open and length L2 when the fall prevention fence is closed, and if the actual amount of contraction L of the spring is L2<L<L1, this indicates that the device is operating normally, and if not, a mechanism is provided in which a magnet attached to the rod passes through the reed switch to notify of an abnormality.

8. 7. The automated warehouse of claim 6, wherein the coil spring is attached so that tension is generated in the direction in which it extends, one reed switch is attached to the housing to detect the length of the coil spring, two permanent magnets are attached to the rod at a distance slightly greater than the change in spring length during normal opening and closing operations of the fall prevention fence, the amount of extension of the spring due to the tension of the wire generated by the weight of the fall prevention fence etc. is length L1 when the fall prevention fence is open and length L2 when the fall prevention fence is closed, and if the actual amount of extension L of the spring is L1<L<L2, it indicates that the device is operating normally, and if not, a mechanism is provided in which a magnet attached to the rod passes through the reed switch to notify of an abnormality.

9. An automated warehouse as claimed in claim 7, in which two reed switches are attached to the housing at a distance slightly greater than the change in spring length during normal opening and closing operations of the fall prevention fence in order to detect the length of the coil spring, and one permanent magnet is attached to the rod at a location midway between the two reed switches, and which has an operation confirmation function which indicates that when L, L1, and L2 are such that L≦L2, the fall prevention fence will not operate normally even if the pedal is pressed by the pallet, and when L1≦L, the wire has become loose and the fall prevention fence will not return to its normal open position.

10. An automated warehouse as claimed in claim 8, in which two reed switches are attached to the housing at a distance slightly greater than the change in spring length during normal opening and closing operations of the fall prevention fence in order to detect the length of the coil spring, and one permanent magnet is attached to the rod at a location midway between the two reed switches, and which has an operation confirmation function which indicates that when L2≦L for L, L1, and L2, the fall prevention fence will not operate normally even if the pedal is pressed by the pallet, and which indicates that when L≦L1, the wire has become slack and the fall prevention fence will not return to the open position normally.

11. 11. The automated warehouse according to claim 7, 8, 9 or 10, wherein the reed switch is connected to a similar reed switch in each storage shelf, and the operation of all connected storage shelves can be confirmed by one or two signal lines.

12. 12. The automated warehouse of claim 11, wherein the reed switches are connected in series for normally closed reed switches and in parallel for normally open reed switches to fulfill the functions of the reed switches.

13. An automated warehouse according to any one of claims 5 to 10, wherein the coil springs according to any one of claims 5 to 10 are replaced with leaf springs, spiral springs, or the like having the same functions.

14. An automated warehouse that uses the vertical movement of a pallet to open and close a fall prevention fence, not limited to the fall prevention fences described in claims 1 and 2, and that has the function of any one of claims 3 to 11.

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