Mobile trolley for storing and retrieving payloads within a warehouse

Abstract

The present invention relates to a material handling system using a mobile dolly that provides efficient storage and retrieval of payloads at multiple levels in a three-dimensional warehouse system. In one embodiment, the mobile dolly includes a first frame having eight wheels, wherein four first wheels of the first frame are configured to move the mobile dolly in an "X" direction, and a second wheel, which is a pinion-mounted wheel of the first frame, is configured to move the mobile dolly in a "Z" direction. The mobile dolly further includes a second frame movably mounted to the first frame, wherein the second frame includes a gear motor, a drive pulley, a drive belt, four lead screw units, a plurality of sensors, and four third wheels, wherein the third wheels are configured to move the mobile dolly in a "Y" direction.

Description

Technical Field

[0001] The present invention relates to a mobile cart, and more particularly to a mobile cart system controlled and managed by a computer subsystem for controlling the guidance to one or more storage locations and the retrieval of payloads from the storage locations.

Background Art

[0002] In the field of material handling, in the most common warehouse environment, many items need to be stored as inventory and taken out and used irregularly. The larger the warehouse facilities, the more items can be stored. Furthermore, large-scale warehouse facilities require a large geographical space. Modern warehouses not only spread over a large distance but also, due to their height, many items can be stacked one above the other for storage. The position and bin of each item can be specified in the three axes of X, Y, and Z. Therefore, the warehouse position of a specific item can be uniquely specified.

[0003] In many warehouses, only a small fraction of the available vertical space is utilized due to reasons such as limited access to items stored at higher levels. Three-dimensional rack systems in the form of automated storage and retrieval systems (often called ASRS or AS / RS) that store items in vertical storage racks have been proposed. However, these vertical systems have several significant commercial drawbacks. In conventional ASRS systems, a single gantry robot moved along long aisles to perform storage and retrieval tasks. While the travel speed was usually good, a limitation was that only one item could be stored or retrieved from the aisle at a time. Parallel processing was also not possible. Next-generation ASRS introduced robots that moved in the XY plane, solving the parallel processing problem. However, this problem is only solved for a specific XY plane. To cover the Z axis, the robot cannot move vertically. Another solution was to install lifts in strategic locations to allow movement in the Z direction. However, such lifts became a bottleneck, requiring the robots to form a queue to move to a different Z level.

[0004] Automated Guided Vehicles (AGVs) are commonly used in warehouses to automatically perform various material handling functions with little to no human intervention. AGVs are generally used to improve safety and reduce overhead by limiting the number of employees required to complete specific material handling tasks. Furthermore, AGVs are reliable and capable of 24-hour continuous operation. Such superior performance compared to manual labor leads to increased efficiency in warehouse facilities. Conventional AGVs have very limited movement directions, with some restricted to movement along the horizontal axis / horizontal plane, and others restricted to movement along the vertical axis / vertical plane.

[0005] While conventional technologies propose movement along the XY and YZ axes, the overall structure, along with the rack system, is extremely complex and cumbersome to operate. Although progress has been made in such automated delivery systems, there is still a need for automated AVGs that are less complex in terms of structure and operation, in order to increase scalability and speed when deploying large-scale systems.

[0006] Furthermore, technologies are needed to improve the efficiency of using limited warehouse space and available energy. [Overview of the project]

[0007] This invention was conceived in view of the above-mentioned limitations, and its purpose is to provide an automated three-axis mobile trolley that can move in all three dimensions, enabling efficient storage and retrieval of payloads (luggage) and maximizing the use of storage space.

[0008] In one aspect of the present invention, a mobile cart for storing and retrieving payloads between at least two collection and delivery stands in a warehouse-type facility. In one embodiment, it includes a first frame comprising a drive system, a control system, and a payload area. The first frame has eight wheels, the first four wheels of the first frame configured to move the mobile cart in the "X" direction. The second wheels of the first frame, which are pinion-integrated wheels, are configured to move the mobile cart in the "Z" direction. Furthermore, it includes a second frame movably mounted on the first frame, the second frame comprising a gear motor, a drive pulley, a drive belt, four lead screw units, a plurality of sensors, and a third four wheels, the third four wheels configured to move the mobile cart in the "Y" direction. A wheel changing mechanism for changing from the "X" direction to the "Y" direction, from the "Y" direction to the "Z" direction, and vice versa enables the mobile cart to achieve three-dimensional movement during operation.

[0009] It should be understood that the systems, apparatus, and technologies described and illustrated herein can be used in a number of situations and environments, including but not limited to warehousing, manufacturing, distribution, and retail. Further forms, purposes, features, aspects, benefits, advantages, and embodiments of the present invention will become apparent from the detailed description and drawings provided herein. [Brief explanation of the drawing]

[0010] The present invention will be more fully understood from the detailed description below, the appended claims, and the appended drawings.

[0011] [Figure 1] Figure 1 shows a mobile trolley (a top view and b bottom view) including a first frame and a second frame positioned to facilitate the storage and retrieval of a payload within a warehouse-type facility, according to one embodiment of the present invention.

[0012] [Figure 2] Figure 2(a) shows a second frame separated from the first frame of a mobile trolley according to one embodiment of the present invention. Figures (b) and (c) show the elevation mechanism of the second frame according to an example of one embodiment of the present invention.

[0013] [Figure 3] Figure 3 shows the operation of a mobile trolley in a multi-tiered storage structure of a warehouse-type facility according to one embodiment of the present invention.

[0014] Those skilled in the art will understand that drawings may be illustrated for simplification and clarity and may not be drawn to scale. For example, the dimensions of some elements in the drawings may be exaggerated relative to others in order to improve understanding of the various exemplary embodiments of this disclosure.

[0015] Note that throughout the drawings, similar reference numbers are used to depict the same or similar elements, features, and structures. [Modes for carrying out the invention]

[0016] For the purpose of facilitating an understanding of the principles of the present invention, embodiments illustrated in the drawings will now be referred to and described using the same language. Nevertheless, it will be understood that no limitation of the scope of the present invention is intended thereby. Any changes and further modifications in the embodiments described, as well as any further applications of the principles of the present invention described herein, are intended to occur in a manner that would ordinarily occur to those skilled in the art to which the invention relates. Although one embodiment of the present invention is shown in great detail, it will be apparent to those skilled in the art to which the invention relates that some features not relating to the present invention may not be illustrated for the sake of clarity.

[0017] The mobile cart systems described below may include any type of automated guided vehicle (AGV), including but not limited to shuttles and powered trolleys. A mobile cart is typically an unmanned, self-propelled vehicle that moves around a guided path or route, such as in a factory, warehouse, distribution center, or on a ramp. Some examples of potential mobile cart applications include handling materials, distributing parts in a warehouse, and moving workpieces or assemblies, such as vehicle chassis, through various stages of a manufacturing process. As will be further described herein, mobile carts can also be used to guide manufacturing equipment to a stationary workpiece and perform a manufacturing process on it. A skilled technician will recognize that there are numerous different types of mobile carts, including, to name a few, those that use optical sensors, magnetic sensors, field sensors, Global Positioning System (GPS) sensors, inertial guidance means, laser guidance, and human control via a joystick or other control device to move the mobile cart along a desired path. The mobile cart systems described below are not limited to any particular type of mobile cart and may be used with any of the examples mentioned above, as well as with other types of mobile carts known in the art.

[0018] Figures 1(a) and (b) show an exemplary mobile cart including a frame, a payload area or platform, a pair of drive mechanisms, and wheels. Of course, the mobile cart may also include other components such as sensors, electronic control units, battery packs, battery chargers, docking systems, and component lifting mechanisms. These other components can be configured and assembled in ways known to those skilled in the art and are therefore not described in further detail. The frame functions as the chassis or structural framework of the mobile cart and can be constructed from various materials according to any number of different arrangements. The payload area or platform is firmly attached to the frame and is preferably designed to carry any cargo for which the mobile cart is designed to transport. In some cases, the mobile cart is expected to transport objects or assemblies (e.g., materials, parcels, etc.), in which case the frame and / or platform may need to be reinforced. As its name suggests, the drive mechanism generally drives or propels the mobile cart as it moves along a guided path. The drive mechanism can also drive the mobile cart or perform other tasks in combination with it. The mobile vehicle is equipped with a power supply consisting of lithium-ion batteries. The power supply may be, but is not limited to, busbars, capacitors, or contactless power supply. The mobile vehicle uses a LIDAR (Light Detection and Ranging) sensor to detect one or more obstacles along its path. Other sensors for obstacle detection may be ultrasonic sensors, IR-based proximity sensors, laser sensors, or vision-based sensors.

[0019] A more detailed description of the drive mechanism is provided below, but it should be understood that the number and position of the drive mechanism on the mobile trolley may vary according to the specific needs of the application. For example, the exemplary mobile trolley includes multiple drive mechanisms with the help of gear motors. In this particular embodiment, both the front and rear drive mechanisms are located on the first frame of the mobile trolley, but other positions of the drive mechanisms are also possible. The wheels of the mobile trolley may be casters or any other suitable type of rotating body, which can help to move the mobile trolley smoothly along a guided path.

[0020] In embodiments of the present invention, a mobile cart is for the storage and retrieval of payloads between at least two collection and delivery stands within a warehouse-type facility. The mobile cart includes a first frame and a second frame that are superimposed on each other and together form a frame structure. In embodiments, the first frame functions as a housing for the second frame. The first frame includes a drive system, a control system, and a payload area. The drive system generally drives, moves, or propels the mobile cart as it moves along the ground or other surface. The drive system may be mounted on the frame, and the number and location of the drive systems may vary depending on the specific needs of the application. For example, an exemplary mobile cart may include a first drive system in front of the mobile cart and a second drive system in the rear, but this is not necessary, and it may include as few as one drive system to propel the mobile cart. The exact number, location, and arrangement of the drive systems may be determined by the nature of the payload that the mobile cart is expected to transport and the operations or turns that the mobile cart needs to perform to follow an intended route or guided path. The first frame consists of four wheels, the first four wheels of the first frame configured to move the mobile trolley in the "X" direction, and the second wheels of the first frame, which are pinion-integrated wheels, configured to move the mobile trolley in the "Z" direction. A second frame is movably mounted to the first frame, and the second frame includes a gear motor, drive pulleys, drive belt, four lead screw units, multiple sensors, and a third set of four wheels, the third set of four wheels configured to move the mobile trolley in the "Y" direction. In this embodiment, the mobile trolley can change axes using the lead screw mechanism (i.e., XY axis change and X / YZ axis change). Relative movement of the frames enables the mobile trolley to change XYZ axes. This mobility allows the mobile trolley to move independently in the Z direction from any point on the storage structure, thus eliminating the need for lifts and bottlenecks.

[0021] A first frame covering the payload area has retractable means for storing and retrieving (storing and retrieving) the payload, the retractable means comprising a plurality of casings having finger-like objects. In exemplary embodiments, the retractable means comprises a retractable arm for pushing / pulling the payload into or out of the payload area for the functionality (i.e., rotatable) of the finger-like objects. Other mechanisms for storage and retrieval may include an underslide fork, a mechanism using a chain and finger-like objects, a gripper mechanism, and the like.

[0022] In one embodiment, a mobile carriage using four mounted first wheels assists in moving the vehicle horizontally, and four mounted second wheels assist in moving the vehicle vertically. In this embodiment, the first / second / third wheels selectively engage or disengage from the track depending on the relative frame position. Thus, the wheels of the mobile carriage are always equipped to move in any direction in which movement is desired. The axis changing mechanism of the mobile carriage is solely responsible for engaging the first wheels with the X-axis, the second wheels with the Z-axis, or the third wheels with the Y-axis. In one embodiment, detection of the relative frame position is performed by an IR-based proximity sensor. Other sensors may be limit switches, laser sensors, ultrasonic sensors, etc. To guide across the track, the mobile carriage uses a vision-based barcode reader. Other positioning systems include laser-based barcode readers, magnetic tape, LIDAR-based navigation, vision-based navigation, laser-guided navigation, and guided wire-based navigation.

[0023] Figure 2 shows a second frame (a) separated from the first frame of a mobile trolley according to one embodiment of the present invention. In one embodiment of the present invention, the second frame, which is movably mounted on the first frame, includes a gear motor, a lifting drive pulley, a drive belt, four lead screw units, a plurality of sensors, and a third set of four wheels, the third set of four wheels configured to move the mobile trolley in the "Y" direction. In an exemplary embodiment, the second frame functions as a support structure for the first frame. The wheel changing mechanism of the mobile trolley enables three-dimensional movement during operation. This mechanism is used to change movement from the "X" to the "Y" direction, from the "Y" to the "Z" direction, from the "X" to the "Z" direction, and both in the reverse direction. The wheel changing mechanism mainly includes a gear motor, a drive pulley, a drive belt, four lead screw units, and proximity sensors (17) mounted for lifting position confirmation. When changing the direction of the mobile trolley, the third set of four wheels is raised or lowered using a gear motor that rotates the wheels clockwise or counterclockwise.

[0024] Sensors used in a mobile cart can include one or more sensors electronically coupled to a control unit or multiple units that provide or collect information regarding the position, alignment, and / or orientation of the mobile cart. The sensors can, of course, be any other type known in the art and, alternatively or additionally, can be included or used as part of a positioning mechanism. In an exemplary embodiment, the sensors are multiple LIDAR sensors that provide 360-degree protection from obstacles. Other examples of sensors include, but are not limited to, infrared, ultrasonic, vision, and laser-based sensors. Further, the lead screw can be of any of several types known in the art that convert or transform rotational motion into linear motion. The lead screw functions by rotating a threaded rod within an internally threaded nut, and the nut is fixed to the part to be moved up and down. The nut moves along the threaded rod as the threaded rod rotates. As is known in the art, the lead screw can be a ball screw, and the nut is a ball assembly that moves and recirculates load-bearing balls along the threads of the threaded rod to enable conversion in a lower-friction and more accurate manner. Further, FIGS. 2-(b) and (c) are diagrams showing an elevation or lifting mechanism using a gear motor of a second frame according to an exemplary embodiment of the present invention.

[0025] Referring to Figure 3, a portion of a warehouse system generally represented by 21 is shown, further defining a multi-level grid of paths and mobile carts (which may also be called carts or shuttles) controlled to move through the grid. The rack structure 21 includes multiple spaced rails extending in all directions, which collectively define multiple paths on which the mobile carts can travel. As will be described later, the multiple directional paths pass beneath storage areas where payloads or materials are stored. The warehouse system may include multiple payload storage levels and multiple cart storage levels on which carts can be stored. The rack structure also includes assemblies configured to move carts between different levels, with or without payloads. Thus, the rack structure defines paths for carts to travel long distances between different level locations. Although the illustrated embodiment is of limited size with only a few levels and storage areas, the warehouse system can have any appropriate number of levels, storage areas, and x, y, and z directional paths. As shown in Figure 3, the mobile carts with second wheels move vertically. The second wheel, which has a built-in pinion, is configured to move the mobile trolley in the "Z" direction.

[0026] A warehouse system may include a controller that executes software instructions to implement control logic for operating the system. The controller may be programmed to control the movement of carts, and the carts may include a processing system that receives instructions from the controller and executes software instructions to control their movement and operation. The carts can determine their own position by any suitable method, such as via a local positioning system, via location markers in the system, or by distance and direction tracking. The controller may communicate directly or indirectly with the carts and with other processing systems of the warehouse system by any suitable method, such as wireless, wired, or IR.

[0027] It should be understood that the foregoing description relates to one or more preferred exemplary embodiments of the present invention. The present invention is not limited to the specific embodiment(s) disclosed herein, but rather is defined only by the following claims. Further, the descriptions included above relate to specific embodiments, and unless a term or phrase is explicitly defined above, should not be construed as limiting the definitions of terms used in the scope of the present invention or the scope of the claims. Various other embodiments and various changes and modifications to the disclosed embodiment(s) will be apparent to those skilled in the art. All such other embodiments, changes, and modifications are intended to fall within the scope of the appended claims.

[0028] As used herein and in the claims, the terms “for example,” “e.g.,” and “such as,” and the verbs “comprising,” “having,” “including,” and their other verb forms, when used in combination with a list of one or more components or other items, are each to be construed as open-ended, meaning that the list is not considered to exclude other, additional components or items. Other terms are to be construed using the broadest reasonable meaning unless used in a context that requires a different interpretation. Reference number JPEG2023550292000002.jpg118143

Claims

1. 1. A mobile dolly for storing and retrieving payloads between at least two pickup and delivery stations within a warehouse-type facility, comprising: a first frame including a drive system, a control system, and a payload area; a second frame movably attached to the first frame; the first frame has four wheels, the first four wheels of the first frame are configured to move the transport carriage in an "X" direction, and the second wheel of the first frame, which is a pinion-integrated wheel, is configured to move the transport carriage in a "Z" direction; the second frame includes a gear motor, a drive pulley, a drive belt, four lead screw units, a plurality of sensors, and a third four wheels, the third four wheels being configured to drive the moving carriage in a "Y" direction of motion; Mobile trolley.

2. 2. The mobile carriage of claim 1, further comprising a wheel changing mechanism for achieving three-dimensional movement during operation, the mechanism being used to change movement from the "X" direction to the "Y" direction, from the "Y" direction to the "Z" direction, and from the "X" direction to the "Z" direction, and vice versa.

3. 3. The moving carriage according to claim 2, wherein the wheel changing mechanism comprises a gear motor (9), a drive pulley (12), a drive belt (16), four lead screw units (14, 15) and a proximity sensor (17).

4. 2. The mobile carriage according to claim 1, wherein the third four wheels are raised or lowered by using a gear motor that rotates the wheels clockwise or counterclockwise when changing direction.

5. 4. The moving cart according to claim 3, wherein a sensor is attached to confirm the lifting position.

6. 2. The mobile carriage of claim 1, wherein the first frame covering the payload area has retractable means for storing and retrieving the payload, the retractable means including a plurality of casings having fingers.

7. 2. The mobile dolly of claim 1, wherein the first four wheels are mounted to assist in moving the vehicle horizontally, and the second four wheels are mounted to assist in moving the vehicle vertically.

8. 10. The mobile carriage of claim 1, wherein the relative movement of the frames allows the mobile carriage to change its X, Y, and Z axes, thereby allowing the mobile carriage to move independently in the Z direction from any point on the storage structure, eliminating the need for lifting and bottlenecks.

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