CN1235782C - automatic storage system - Google Patents

Abstract

An automated storage system employing multiple cranes, comprising: a pair of storage areas for storing workpieces, the storage areas being arranged in parallel with each other; two stacker cranes for conveying the work pieces; a crane path disposed between the storage areas to allow the two stacker cranes to move; two crane stops are provided at the two ends of the crane path, respectively, for placing the crane. Since two cranes are used simultaneously, one automated storage system can handle very large transport volumes. Therefore, the cost of the production facility is reduced, and even if one crane malfunctions, other cranes can be used. The faulty crane does not affect the whole system.

Description

automatic storage system

technical field

The present invention relates generally to automated storage systems for storing and retrieving workpieces. More specifically, the present invention relates to an automatic storage system with at least two multiple cranes and a control method thereof.

Background technique

According to different purposes, people have developed storage systems for storing workpieces with various structures and functions. Specifically, the storage systems used on the production line are combined with various processing equipment on the production line. Therefore, storage systems must supply accurate quantities of workpieces to processing equipment within the required time, and securely store other workpieces.

The automatic storage system disclosed in US Pat. No. 3,817,406 has a storage area in which workpieces can be reliably loaded and a stacker crane for loading workpieces in the storage area. The storage area is multi-layered, in which the frames are connected horizontally and vertically to continuously form a square space with regular dimensions. Since the lower part of the stacker crane is coupled with the rail formed on the lower surface of the stacker crane, the stacker crane can move along the storage area. Therefore, the workpieces carried by the automatic storage system are transferred by the stacker crane. And, when the workpiece reaches the designated position in the storage area, the stacker crane automatically places the workpiece in the designated position.

However, in this automatic storage system, only one crane can be operated in the stacker. If fewer workpieces are transported in the stacker, only one crane can be used to transport the workpieces. However, if the transportation volume is large and the transportation path is complicated, one crane cannot meet the transportation volume of the stacker, and multiple stackers need to be used at the same time.

If one crane fails and stops its delivery operations, the entire production line cannot work until the crane is fully restored.

Contents of the invention

Accordingly, an object of the present invention is to provide an automatic storage system and a control method thereof with improved transport capacity.

Another object of the present invention is to provide an automatic storage system in which a failure of a crane does not affect the entire production line.

In order to achieve the object of the invention, according to one aspect of the present invention, an automatic storage system is provided, comprising: a pair of storage areas for storing workpieces, the storage areas are arranged in parallel to each other; a storage controller for controlling the automatic storage system; conveying workpieces The first and second stacker cranes; respectively control the first and second stacker crane controllers of the first and second stacker cranes, the first and second stacker crane controllers are controlled by the storage controller; set at a crane path between storage areas to enable movement of said first and second stacker cranes, wherein the crane path has a first crane operating area on which the first crane can operate, and a second crane can operate on the second crane operating area; a buffer area having a temporary storage unit in one of the storage areas, the buffer area divides the crane path into a first crane operating area and a second crane operating area, by Either one of said first and second cranes loads workpieces into a temporary storage unit, and the other of said first and second cranes receives workpieces from a temporary storage unit; for placing the first and second cranes The first and second docking stations are set at the two ends of the crane path respectively.

Description of drawings

1 is a perspective view of a stacker crane and a loading unit in an automatic storage system according to a preferred embodiment of the present invention;

Fig. 2 is the top plan view of the automatic storage system of a preferred embodiment of the present invention;

Fig. 3 is the perspective view showing the transportation relation between the automatic storage system of a preferred embodiment of the present invention;

Figure 4 is a flowchart showing the steps of controlling the automatic storage system of the preferred embodiment of the present invention;

Fig. 5 is a detailed flowchart of the initialization step shown in Fig. 4;

Fig. 6 is a detailed flowchart of the mode conversion step shown in Fig. 4;

FIG. 7 is a detailed flow chart of the additional zone transport processing steps shown in FIG. 4;

Fig. 8 is the top view of the modified automatic storage system of the present invention;

Figure 9 is a top plan view of an automated storage system according to another embodiment of the present invention.

Detailed ways

The invention provides a new and improved automatic storage system, which includes a storage area with constant space, a loading device for loading workpieces in the storage area, and a controller. This automatic storage system is of the stacker type with a storage area and a loading device.

In the place of the stacker 100 shown in FIG. 3, the system is integrated with the processing equipment of the production line, or separate from the processing equipment in order to load workpieces subjected to constant processing steps. Automated guided vehicles (AGVs) 150 are used to transport workpieces 120 in the bay. AGV150 transports workpieces in and between warehouse partitions. Compared with the rail-guided vehicle (RGV) that moves along the track, the AGV does not need a track and can move directly to the floor of the production line. As shown in FIG. 3 , the AGV receiving the workpiece 120 from the stacker 100 performs an operation of transporting the workpiece 120 to a designated stacker according to a control command. As another method of transporting the workpieces 120 to a given stacker, a monorail 142 coupled to the stacker 100 is used to transport the workpieces 120 from one stacker 100 to another stacker 100, or between different warehouse partitions. Shipping between. A monorail 142 passes from one side of the stacker 100 . The monorail vehicle 110 running on the monorail 142 loads and transports the workpiece 120 from the stacker 100, performs a series of transfer operations to transport the workpiece 120 to another stacker 100a.

The transfer instruction is transmitted from the host computer 200 to the stacker controller 202 which controls the stacker 100 . In the stacker controller 202 , a series of transfer commands are then transmitted to the crane controller 204 .

The workpiece 120 conveyed by the automatic guided vehicle 150 or the monorail vehicle 110 is loaded in the stacker 110 . In this case, a method of loading the workpiece 120 to a designated position is described in more detail with reference to FIGS. 1 and 2 .

The automatic storage system of the present invention has a storage area 101 loaded with workpieces, a first stacker crane 112, a second stacker crane 114, a crane path 103 on which the first stacker crane 112 and the second stacker crane 114 move , the controller 202 (see FIG. 3 ) that controls the automated storage system, and the crane controller 204 that controls the first stacker crane 112 and the second stacker crane 114 (see FIG. 3 ). The structure of the storage area 101 is shown in FIG. 1 . In order to place workpieces efficiently, the frames 121 are horizontally formed at regular intervals. Protruding pieces 122 with regular heights are formed on lateral surfaces of the frame 121 . The storage area 101 is finally multi-layered to form a square space with regular dimensions in length and width. The square space can be adjusted according to the kind and size of stored workpieces.

Stacker cranes 112 and 114 are used to load workpieces 120 in the square space. The structure of the first stacker crane 112 will be described below. Wheels 130 are formed at the lower portion of the first stacker crane 112 , which run on the crane path 103 . The mount 132 supports the main body 134 . The cable 137 is connected with the support 132 for transmitting the command of the crane controller 204 . A constant length slot 135 is formed on the main body 134 so that the horizontal arm 136 can move vertically along the slot 135 of the main body 134 . At one end of the horizontal arm 136 , a rotating arm 138 , which is rotatable about the vertical axis of the horizontal arm 136 , is formed. A wider flat-shaped contact piece 140 is formed on one side of the rotating arm 138 to securely load a workpiece. In the stacker crane 112 having such a structure, the steps of safely loading the workpiece 120 will be described below with reference to FIG. 2 . Through the above-mentioned automatic guided vehicle 150 (see FIG. 3 ), the workpiece 120 reaches the first entrance 104 of the automatic storage system 100 to be transferred. Subsequently, in the automated storage system 100, the alignment devices 108 and 108a rotate the conveyed workpiece 120 by 90°. Thus, as shown in FIG. 2, all workpieces 120 in the automatic storage system are aligned in one direction. As described above, the aligned workpieces 120 are loaded by the crane 112 at a specific location in the storage area 101 . Specific locations are designated by the controller 202 which receives transfer instructions summarizing the entire production line from the host computer and controls the automatic storage system 100 . The transfer command is transmitted to the crane controller 204 which controls the crane 112 which loads the workpiece 120 at a specific location in the storage area 101 . Crane 112 moving along crane path 103 near a particular location moves horizontal arm 136 vertically to load a workpiece at the particular location. Also, the crane 120 rotates the swivel arm 138 to safely load the workpiece 120 at a specific location. Of course, the recovery operation can be performed in the same manner. Since automated storage systems may have multiple inlets and outlets, as shown in FIG. 2, a second inlet 102 and a first outlet 106 are formed in the system.

As mentioned above, the adjustment devices 116 and 118 and the monorail vehicle 110 transfer workpieces from one operating warehouse section to another, or between automated storage systems. First, the workpiece 120 reaches the adjustment devices 116 and 118 by means of the crane 112 . Since there is a constant height difference between devices 116 and 118 and monorail 110 , adjustment devices 116 and 118 move workpiece 120 vertically to mate with monorail 110 . Accordingly, adjustment devices 116 and 118 function to securely place workpiece 120 onto monorail 110 .

If the storage and transfer of workpieces is large, in a preferred embodiment, the automatic storage system for storing and retrieving workpieces uses two cranes at the same time. The stacker crane of the present invention will be described with reference to FIGS. 4 to 7 .

Fig. 4 shows the control steps of the automatic storage system of the present invention. The automatic storage system divides the operation mode into dual mode using at least two cranes and single mode using only one crane. In the case of a dual mode, as a rule, delivery operations are generally carried out in each designated area. If a shipping order is issued in an additional designated area, the shipping operation adopts a control method based on processing steps in the additional area.

The method of controlling the automatic storage system of the present invention includes the following steps. The operation mode is set in the automatic storage system with at least two cranes (initialization step S100); the transport operation is performed (S110). In case the current operation mode is changed to single mode or dual mode during the shipping operation, it is checked whether the current mode is changed during the shipping operation (S120). If the current mode needs to be changed, a mode change processing operation is performed (S130). It is checked whether it is an extra area delivery (S140). If yes, an additional area delivery operation is performed (S150). Subsequently, it is checked whether the shipping operation is completed (S160). If done, stop the operation.

FIG. 5 shows details of the initialization steps shown in FIG. 4 . Check previous modes, either single mode with only one crane or dual mode (S200) with two cranes. In case of the single mode, it is checked whether there is an operable crane executing the single mode (S210). If there is no operable crane, an alarm is issued (S220). Then, the system operator handles the above situation (S230). The system operator corrects the error of the crane, makes the crane operable or issues another command. If there is an operable crane, it is checked whether there is an unselected crane on the entire transfer path of the operable crane (S240). If there is an unselected crane, it is transported out of the transfer path (S250). Subsequently, the initialization step ends.

In the dual mode, check whether both cranes are normal (S260). If abnormal, an alarm is issued (S270). Then the system operator handles the above situation (S280). If normal, the positions of the cranes are checked in order to transfer each crane to a designated position (S250). Subsequently, the initialization step ends.

The initialized automatic control system checks whether a substantially non-operating stacker is located in a safe area (such as a docking station). Well, another operating stacker crane has all the operating powers. In the case of dual mode, the two cranes in the stacker are basically transported in one area and operate independently. If two cranes trespass into each other's area, the cranes operate by other methods specified.

If it is necessary to change the mode due to a failure of the stacker crane or a change in the conveying amount, the automatic storage system is controlled by the control method shown in FIG. 6 .

As shown in FIG. 6, if it is necessary to change the mode (S310), the operation is stopped (S320) and the current operation mode is changed. If the previous mode was single mode (S340), it is required to change the mode in two cases. One case is to increase the operation of a stacker crane not employed in single mode or to restart a stacker crane for fault repair. In the above case, the single mode is converted to the dual mode (S332). Even though it is not shown in the figure, another situation is to replace the faulty stacker crane currently used in single mode with another stacker crane. In the above cases, single mode is converted to single mode.

In yet another case, the dual mode continues and is later converted to single mode. If one of the two cranes is out of order and only the other can be operated, or the system operator switches modes as needed, the dual mode is changed to the single mode (S334).

Since the next steps of the mode conversion are the same as the above-mentioned steps, descriptions thereof are omitted.

As mentioned above, in dual mode, two cranes operate independently in one area of the stacker. However, if the delivery order exceeds the respective operating areas, the two cranes will operate according to the method shown in Figure 7.

Referring to FIG. 7 , in the case of extra area delivery ( S400 ), it is necessary to check whether the preset parameter is direct delivery or buffer delivery ( S410 ). In direct transfer, the operating crane moves directly to the other transfer area to transfer the workpiece to the final destination. In buffer transport, a buffer area is set between the transport areas to transport the workpiece to the end point without causing the crane to leave an operating area.

In the direct delivery, if the crane of the terminal area is located on the transfer path (S420), the crane moves out of the transfer path (S440) to load the workpiece. In buffer delivery, the cranes in the delivery area transfer the workpiece to the buffer zone (S450), and the cranes in the terminal zone deliver the workpiece to the terminal (S460).

The above control method is exemplarily described with reference to FIG. 2 as follows. Assuming that the crane path is intentionally divided into areas A and B, there are first and second instructions (the first instruction loads the workpiece from A1 to A2 via the monorail, and the second instruction loads the workpiece from B1 to B2.) If both Both cranes 112 and 114 are checked to be normal, and the first crane 112 is selected to execute the first transfer command. Since there are no other cranes when the first crane 112 moves from A1 to A2 in the first transfer order, the other crane 114 need not move. Another crane 114 is selected as the second crane 114 . Since the conveying paths do not overlap, the first crane 112 moves from A1 to A2, and the second crane 114 moves from B1 to B2, respectively executing the conveying instructions. Therefore, it is possible to simultaneously perform the transfer operations of carrying the workpieces from A1 and B1 to A2 and B2, respectively. With this control method, two cranes can be operated simultaneously.

There may also be another situation where the first transfer command is a transfer command from A1 to A2 and the second command is a transfer command from A3 to A4.

In this case, since the transmission paths of the first order and the second order do not overlap with each other, the two cranes can also operate simultaneously. Regardless of the intentional division of zone A or zone B, two cranes operate in one zone at the same time. Certainly, those of ordinary skill in the art will understand that: a boundary area should be set to prevent two cranes from colliding with each other.

However, in the case where the first command is an A1 to B2 transfer command and the second command is a B1 to A2 transfer command, the transfer paths of the first and second transfer commands overlap each other. In order to execute the first order, the first crane 112 selected for execution of the first transfer order must move to zone B. Therefore, in order for the second crane 114 to execute the second delivery order from B1 to A2, the transfer paths inevitably overlap each other. In this case, the two cranes operate sequentially. That is, one crane runs first, and after the crane finishes running, the other crane runs again to prevent them from colliding on their respective conveying paths.

FIG. 8 shows a modification of the automatic storage system 100 shown in FIG. 2 . The modified system includes an auxiliary stacker crane 160 and two stacker cranes. Descriptions of the same parts as those shown in FIG. 2 are omitted. The auxiliary stacker crane 160 is located in the center of the crane path (Zone C). If the two cranes of the automated storage system are operating normally, the auxiliary stacker crane 160 remains on standby. If, for example, the crane 112 breaks down, the auxiliary crane 160 replaces the failed crane 112 to execute the transmission command in the A area. And the faulty crane 112 is placed at the docking station in the C area for repair. In this way, a faulty stacker crane does not affect the throughput of the entire system, and the entire system can operate constantly and safely under all circumstances.

Figure 9 shows another preferred embodiment of the automated storage system. Compared with the automatic storage system, the automatic storage system shown in Fig. 9 only operates in its own area intentionally set, except that the two cranes operate at the same time.

Detailed descriptions of the same parts between FIG. 9 and FIG. 2 are omitted. Area C shown in FIG. 9 is a kind of buffer zone, and represents an instruction to carry a workpiece from A1 to B1. The crane 112 runs freely in zone A as indicated by the arrow, but cannot enter zone C. Therefore, the crane 112 stores the workpiece in the temporary storage unit 164 and returns to the A area. The crane 114 in the B zone moves to the temporary storage unit 164, receives the workpiece and loads the workpiece at B1 in the B zone.

As mentioned above, an automated storage system can handle very large transfer volumes thanks to the possibility of using two cranes at the same time. Therefore, the cost of production equipment is reduced, and, even if one crane fails, other cranes can be used. A faulty crane therefore does not affect the entire system.

Although the present invention has been described in detail with respect to specific embodiments, it should be understood that the present invention is not limited to the embodiments, and various changes and modifications can be made without departing from the spirit and scope of the present invention.

Claims (2)

1. An automatic storage system comprising: a pair of storage areas for storing workpieces, the storage areas being arranged parallel to each other; a storage controller controlling the automated storage system; first and second stacker cranes for conveying workpieces; first and second stacker crane controllers respectively controlling the first and second stacker cranes, the first and second stacker crane controllers being controlled by the storage controller; a crane path disposed between the storage areas to enable movement of the first and second stacker cranes, wherein the crane path has a first crane operating area on which the first crane can operate, and a second crane on which the The second crane operation area on which the crane operates; a buffer area having a temporary storage unit in one of the storage areas, the buffer area divides the crane path into a first crane operating area and a second crane operating area, whereby the first and second crane operating areas any one of the two cranes loads the workpiece into the temporary storage unit, and the other of the first and second cranes receives the workpiece from the temporary storage unit; First and second docking stations for placing the first and second cranes, the two docking stations are respectively arranged at the two ends of the crane path. 2. The automated storage system of claim 1, wherein the first and second controllers prevent collisions between the first and second cranes.

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