Patent Application
20080077273
The embodiments of the invention will be better understood from the following detailed description with reference to the drawings, in which:
In view of the foregoing, an embodiment of the invention provides a method of transporting workpieces to tools in an automated transportation system. More specifically as shown in flowchart form in
Next, as shown in item 102, the method directs the automated transport vehicle to travel from the first loadport, along an interbay loop, to an intrabay loop. The intrabay loop comprises a transport route around the tool and the interbay loop comprises a transport route that connects the loadport to a plurality of intrabay loops. The then method directs the automated transport vehicle to travel along the intrabay loop in item 104.
As show by the decision box in item 106, the automated transport vehicle is directed to stop at a tool loadport of the tool (in item 108) only if the tool is available to work on the workpieces. If the tool is not available to work on the workpieces when the automated transport vehicle arrives at the intrabay loop, as shown by the arrow from item 106 to item 104, the method directs the automated transport vehicle to continuously travel around the intrabay transport loop until the tool is available.
Referring now to
The “first location” mentioned above is shown as a first loadport 206, but can be any loadport at any of the tools 214-218. Many intrabay loops 210-213 are shown connected to the first loadport 206 by an interbay loop 208. The intrabay loops 210-213 comprises transport routes around one or more tools 214-218. The interbay loop 208 comprise one or more transport routes that connects the loadport 206 to the different intrabay loops 210-213 and can overlap with some of the intrabay loops 210-213.
The method directs one of the automated transport vehicles (e.g., vehicle 222) to travel along the interbay loop 208 and stop at a tool loadport of one of the tools (e.g., tool 218) only if tool 218 is available to work on the workpieces 204. If tool 218 is not available to work on the workpieces 204 when automated transport vehicle 222 arrives at intrabay loop 213, the method directs automated transport vehicle 222 to continuously travel around intrabay transport loop 213 until tool 218 is available.
Each of the intrabay loops 210-213 comprise a circular transport route, as shown by the travel direction arrows, that can be continuously traversed. Thus, the automated transport vehicles 220-224 can continuously move along the intrabay loops 210-213 without having to exit the interbay loops 210-213 and without having to stop. Thus, the automated transport vehicles 220-224 comprise portable zero footprint storage locations while they are continuously circling the intrabay loops 210-213 waiting for the tools 214-218 to become available to accept the workpieces 204 they hold.
Thus, as shown above, the dispatching (in item 100) of the automated transport vehicles 220-224 is performed irrespective of whether the tool is available to receive the workpieces. Thus, workpieces can be sent to the next tool on which they need to be processed, without having to wait in a dedicated waiting location or automated transport vehicle storage facility 230 for the tool to become available, and such storage location(s) 230 can be minimized or eliminated. Further, because the intrabay loops 210-213 are closer to their respective tools than are the storage locations 230, there is less delay in moving the automated transport vehicles 220-224 to the tools 214-218 when the tools become available. In addition, controls can be put in place to ensure that limits are placed on the number of automated transport vehicles that are allowed in any given interbay loop to avoid inefficiencies associated with overcrowding.
The embodiments of the invention and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments of the invention. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments of the invention may be practiced and to further enable those of skill in the art to practice the embodiments of the invention. Accordingly, the examples should not be construed as limiting the scope of the embodiments of the invention. The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments of the invention have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments of the invention can be practiced with modification within the spirit and scope of the appended claims.
