Pallet transport device

Abstract

A pallet transportation device 10 comprises: a top plate 20 on which a wheeled pallet is placed; and a drive unit provided below the top plate 20. The top plate 20 has rails 21 for the wheels of the pallet. The wheels can be rotated along the rails 21 so that after the pallet has been placed on the rails, the pallet can be secured. The drive unit has a sensor 12 for detecting peripheral conditions, and a drive wheel 11 that performs driving on the basis of the results of detection by the sensor 12. This configuration makes it possible to provide a highly versatile pallet transportation device that obviates the need for machining of the wheeled pallet and that enables movement similar to manual transportation.

Description

Technical Field

[0001] The present invention relates to a pallet handling device.

Background Art

[0002] Conventionally, the transportation of goods using a pallet with wheels has been carried out. A pallet with wheels is a trolley with wheels attached to a platform on which an object to be transported is placed. For example, if it has a structure with wheels attached to a cage, it is called a cage trolley, a cage car, a roll box pallet, a cargo container, a combi container, etc.

[0003] Pallets with wheels are widely used assuming manual transportation, but technologies for automating the movement of pallets with wheels are also being studied. For example, Patent Document 1 discloses "an embodiment related to an autonomous mobile device such as a self-propelled robot 1 that automatically connects to and pulls a towed trolley such as a cage trolley 2, and a transportation system using this self-propelled robot 1."

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As a robot for automatically transporting a pallet with wheels such as a cage trolley, in addition to the towing type disclosed in the cited reference 1, a forklift type, a lifting type, etc. can be considered. Among these, the towing type has disadvantages such as a large turning radius and inability to rotate in place. The forklift type has disadvantages such as very high requirements for the weight, size, and output of the robot for lifting the pallet. The lifting type has several disadvantages, including reduced safety against tipping depending on the relationship between the top plate size and wheel position, increased design difficulty due to limited space when the design involves the robot tucked under the floor of the cage trolley, the orientation of the cage trolley's casters potentially interfering with the robot's sensing and movement control, and the need for a mechanism on the cage trolley side for docking with the robot. Common challenges in all these methods include the need for a person to position the cart in the designated location, the need to align the direction of the casters, the time required for positioning for docking, and the need for time to move the empty cart.

[0006] Cage carts and similar equipment are standardized based on the assumption of manual transport, and the layout of aisles and other areas is also based on the assumption of manual transport. Furthermore, they are widely used as returnable containers that are repeatedly transported between designated locations. To automate the movement of these cage carts and similar equipment, it is necessary that they can be rotated on-site, require no modification to the cage carts, and be inexpensive. However, conventional technology could not satisfy these requirements, and the automated transport of wheeled pallets such as cage trolleys lacked versatility. For example, it was not possible to automate the operation of existing cage trolleys as is.

[0007] Therefore, the present invention aims to provide a highly versatile pallet transport device. [Means for solving the problem]

[0008] To achieve the above objective, one representative pallet transport device of the present invention comprises a top plate on which a wheeled pallet is placed, and a drive unit provided below the top plate, wherein the top plate has rails for the wheels of the pallet, and the pallet can be fixed after the wheels are rotated along the rails and the pallet is placed on it, and the drive unit comprises a sensor for detecting the surrounding conditions and a drive wheel that is driven based on the detection result from the sensor.

[0009] According to the present invention, a highly versatile pallet transport device can be provided. Other problems, configurations, and effects will be clarified by the following description of the embodiments. [Brief explanation of the drawing]

[0010] [Figure 1] External perspective view of a pallet transport device (Part 1) [Figure 2] External perspective view of a pallet handling device (part 2) [Figure 3] External perspective view (part 1) of a pallet transport device with a cage trolley mounted on it. [Figure 4] External perspective view (part 2) of a pallet transport device with a cage trolley mounted on it. [Figure 5] Three-view drawing of a pallet transport device (Part 1) [Figure 6] Three-view drawing of a pallet transport device (Part 2) [Figure 7] Three-view drawing (Part 1) of a pallet transport device with a cage trolley mounted on it. [Figure 8] Three-view drawing (part 2) of a pallet transport device with a cage trolley mounted on it. [Figure 9] External perspective view (part 1) of the pallet transport device of Example 2 [Figure 10] External perspective view (part 2) of the pallet transport device of Example 2 [Figure 11] Side view of the pallet transport device of Example 2 [Figure 12] Front view of the pallet transport device of Example 2 [Figure 13] Diagram illustrating the operation control of the pallet transport device according to Example 3. [Modes for carrying out the invention]

[0011] The following examples will be described with reference to the drawings. [Examples]

[0012] Figure 1 is an external perspective view of the pallet transport device 10 disclosed in Example 1. The pallet transport device 10 includes a top plate 20 on which a wheeled pallet (e.g., a cage cart) is placed, and a drive unit provided under the top plate 20.

[0013] The top plate 20 is substantially rectangular and has two rails 21 along two longitudinal sides (long sides). Each rail 21 has a rotating member 22 at both ends. Also, two drive wheels 11 are provided at the center of the long side and between the two rails 21. Furthermore, sensors 12 and swivel casters 13 are provided on two short sides (short sides) of the top plate 20, respectively. The sensor 12 is an external sensor such as a LiDAR, a camera, etc., and detects the surrounding conditions. The swivel caster 13 improves the tipping safety by maintaining the inclination of the top plate 20.

[0014] The sensor module including the sensor 12 and the drive wheel module including the drive wheels 11 are communicatively connected to form a drive unit. The drive unit controls the autonomous driving of the pallet transport device 10 based on the surrounding conditions detected by the sensor 12, the preset route information, etc. Here, the two drive wheels 11 can be independently controlled in rotation, and the pallet transport device 10 can move forward, backward, rotate in place, etc. by differential two-wheel drive.

[0015] In FIG. 1, the rotating member 22 functions as a slope connecting the surface on which the drive wheels 11 travel and the surface of the rail 21. FIG. 2 shows a second state in which the rotating member 22 functions as a vehicle stopper that keeps the wheels of the pallet on the rail. The first state and the second state can be switched by the rotation of the rotating member 22. Furthermore, the structure may include a locking mechanism to stop the rotation of the rotating member 22 itself. For example, a receiving round hole can be provided on the rail 21 side, and the rotating member 22 can be fixed by a round drop. Adopting a round drop structure has the advantage that workers can approach the cage trolley 30 from the position in which it was pushed in. Since multiple cage trolleys are sometimes lined up with their long sides aligned, being able to approach them directly from the position in which they were pushed in is important from the standpoint of work efficiency. Also, since cage trolleys can weigh around 300 kg, the rotating member 22 must be strong enough not to break even if the wheels 31 hit it when it is in a wheel-stopping state during acceleration or deceleration, and the round drop structure can meet this requirement. In addition, the components that make up the round drop structure can be made of general-purpose parts, making it easy to lock and unlock, inexpensive, and readily available.

[0016] Figures 3 and 4 are external perspective views of the pallet transport device 10 with the cage trolley 30 mounted on it. In Figure 3, the rotating member 22 is in the first state (slope), and in Figure 4, the rotating member 22 is in the second state (wheel stopper).

[0017] The cage trolley 30 is equipped with four wheels 31 on its bottom. As shown in Figure 3, when the rotating member 22 is functioning as a ramp, the worker can push the cage trolley 30 and rotate the wheels 31 along the rail 21 to place the cage trolley 30 onto the top plate 20 of the pallet transport device 10.

[0018] Subsequently, as shown in Figure 4, if the worker rotates the rotating member 22 to function as a wheel stopper, the wheels 31 of the cage trolley 30 can be prevented from falling off the rail 21, thereby fixing the cage trolley 30 in place.

[0019] Figures 5 and 6 show three-view drawings of the pallet transport device 10. In Figure 5, the rotating member 22 is in the first state (slope), and in Figure 6, the rotating member 22 is in the second state (wheel stopper). Similarly, Figures 7 and 8 show three-view drawings of the pallet transport device 10 with the cage trolley 30 mounted on it. In Figure 7, the rotating member 22 is in the first state (slope), and in Figure 8, the rotating member 22 is in the second state (wheel stopper).

[0020] As shown in Figures 5 to 8, the rail 21 is formed by a surface lower than the top surface of the top plate 20. Therefore, the cage trolley 30 can be easily placed on the pallet transport device 10. Furthermore, the drive wheels 11 are positioned between the two rails 21. This allows the drive wheels 11 to fit inside the footprint of the trolley 30. Furthermore, by making the underside of the top plate 20 higher than the surface of the rails 21 and arranging the drive wheels 11 between the two rails 21, the space for arranging the drive unit can be increased, and the diameter of the drive wheels 11 can be made larger than the height from the surface on which the drive wheels 11 run to the surface forming the rails 21. Increasing the diameter of the drive wheels 11 contributes to improving the running performance of the pallet transport device 10.

[0021] Here, the size of the cage trolley 30 is standardized, but there is not just one size; multiple sizes exist. It is desirable that the size of the top plate 20 and the width of the rails 21 match the standard of the cage trolley 30. Since the drive unit is modular, it can be fixed to top plates of different sizes in a positional relationship that matches the size of the top plate. In this case, the drive unit controls the movement based on parameters set according to the size of the top plate.

[0022] Alternatively, a docking mechanism may be provided between the top plate 20 and the drive unit, allowing the drive unit to be attached to and detached from the top plate 20, and the drive unit may autonomously perform positioning and attachment / detachment to the top plate 20. With this configuration, no processing is required for the cage trolley 30. In addition, the wheels 31 of the cage trolley are fixed by the rails 21 and do not interfere with sensing or driving control. Furthermore, a larger space can be secured than in a configuration where the cage trolley 30 is tucked under the floor surface, thus reducing the difficulty of the design. Furthermore, in a configuration where the drive unit autonomously performs positioning and attachment / detachment to the top plate 20, the number of top plates 20 and the number of drive units can be determined independently, enabling flexible operation at a low cost. Alternatively, a docking mechanism may be provided between the top plate 20 and the drive unit, allowing for manual positioning and attachment / detachment. In this configuration, the worker can manually switch the top plate 20 and the drive unit depending on the situation at the site (for example, when the item to be transported changes).

[0023] In this manner, the disclosed pallet transport device 10 is loaded with a cage trolley 30 by an operator. At this time, the wheels 31 of the cage trolley 30 are guided by the rail 21, eliminating the need for operator positioning. Furthermore, there is no need to dock the cage trolley 30 with the pallet transport device 10. In addition, there is no need to consider the orientation of the casters when controlling the movement of the pallet transport device 10. Since the cage trolley 30, once loaded, remains on the trolley until the worker unloads it, it is particularly suitable for regularly scheduled transportation. Furthermore, by adding a mechanism for lowering the cage trolley 30 and making it controllable in conjunction with the rotation mechanism of the rotating member 22, it will be possible to handle a type of transportation where there is a worker at the delivery source and deliveries are made to multiple destinations from there. To give a specific example, • At the distribution center on the first floor, the worker only performs the task of placing the cage trolley onto the pallet transport device 10. The pallet transport device 10 goes to the delivery destination, unloads the cage trolley, and returns to the collection and delivery center. • The worker places the next cage cart onto the returned pallet transport device 10. Transportation can be carried out by repeating the above process. When returning the cage trolley to the distribution center, the relationship between the delivery destination and the origin should be reversed. This type of transportation is suitable for situations such as construction sites, where a very large number of cage trolleys need to be delivered in a single day, and where the delivered cage trolleys are left there for several days. Furthermore, the pallet transport device 10 has a structure that allows for equivalent forward and reverse movement, and enables on-the-spot direction changes (pivot turns). It can also utilize aisles and elevators in the same way as when transporting pallets manually. By positioning the drive wheels 11 near the rails 21, the width between the two drive wheels 11 can be increased, providing high stability against tipping. The pallet transport device 10 requires fewer parts, resulting in low cost. Its weight, size, and power output can also be kept low. Therefore, it is possible to make the pallet transport device 10 light enough for a person to lift. Moreover, because the pallet transport device 10 is thin and has a top plate 20, it can be stacked. That is, it can be used by stacking and storing the pallet transport devices 10 and then unloading them for use. Additionally, regular courier services can be used to transport the robot itself for shipping, returns, etc. [Examples]

[0024] Figure 9 is an external perspective view of the pallet transport device 110 disclosed in Example 2. Figure 10 is an external perspective view of the pallet transport device 110 disclosed in Example 2 with a wheeled pallet placed on it. Figure 11 is a side view of the pallet transport device 110 disclosed in Example 2. Figure 12 is a front view of the pallet transport device 110 disclosed in Example 2.

[0025] As shown in Figures 9 to 12, the pallet transport device 110 comprises a top plate 120 on which wheeled pallets 130 are placed, and a drive unit provided beneath the top plate 120. The top plate 120 is roughly rectangular in shape and has two rails 121 on it. The rails 121 extend in the longitudinal direction of the top plate 120.

[0026] The drive shaft of the drive unit is located below the top plate 120, but the drive wheels 111 are positioned outside the long side of the top plate 120. This allows the diameter of the drive wheels 111 to be larger than the height of the top plate 120 from the floor. The larger drive wheels 111 contribute to improved running performance, and the lower top plate 120 contributes to easier loading of pallets 130. The drive wheel 111 has a rotation axis perpendicular to the rail 121. That is, it can travel in the direction of extension of the rail 121 (the longitudinal direction of the top plate 120).

[0027] The pallet transport device 110 is equipped with four drive wheels 111 corresponding to the four corners of the top plate 120. Furthermore, the pallet transport device 110 is equipped with auxiliary wheels 113 near the center of the long side of the top plate 120. For example, Mecanum wheels or omnidirectional casters may be provided on the outside of the center of the long side. Alternatively, conventional casters may be provided on the inside of the center of the long side.

[0028] The four drive wheels 111 are preferably Mecanum wheels, for example. If the drive wheels 111 are Mecanum wheels, in addition to traveling along the longitudinal direction of the top plate 120, movement in the short direction and pivot turns become possible. The two auxiliary wheels 113 contribute to improving the load-bearing capacity of the pallet transport device 110. Using omni-wheels as auxiliary wheels 113 can improve driving force. Using omni-directional casters allows for smooth movement in all directions while reducing costs and weight compared to a configuration using omni-wheels. Using standard casters allows for even greater cost reduction than a configuration using omni-directional casters.

[0029] The pallet 130 is equipped with two rows of six wheels 131. By placing these two rows of wheels 131 into two rails 121, the pallet 130 can be placed on the pallet transport device 110. At least some of the wheels 131 are equipped with a locking mechanism 132. Since the pallet 130 can be fixed in place by locking the locking mechanism 132 while the pallet 130 is on the pallet transport device 110, a locking mechanism is not required for the pallet transport device 110. Furthermore, if a ramp is provided on the floor to guide the running surface of the pallet 130 to the height of the rails 121, a ramp member is not required for the pallet transport device 110.

[0030] There is a space 122 between the two rails 121. A sensor and a control unit that determines the control content of the drive wheel 111 based on the detection results from the sensor can be placed in this space. [Examples]

[0031] As Example 3, an example of operation control for a pallet transport device will be described. For convenience, the pallet transport device 10 from Example 1 will be used as an example, but similar operation control is possible even with the pallet transport device 110. Figure 13 is an explanatory diagram of the operation control of the pallet transport device 10. The pallet transport device 10 determines the control content based on route data 51 and sensor data 52 (53). The route data 51 may be provided from an external source, or it may be generated by the pallet transport device 10 from map data, etc. The sensor data 52 is the result of detection of the surrounding conditions of the pallet transport device 10.

[0032] Furthermore, the pallet transport device 10 receives information about the operator's operation from the operator's terminal 40 (54) and switches whether or not it is allowed to move (56). Specifically, the pallet transport device 10 executes drive control on the condition that it has received permission from the operator (56).

[0033] Thus, in the operation of Embodiment 3, the pallet transport device 10 automatically determines how to travel, but whether or not to travel depends on the operator. That is, it only travels while the operator is performing the authorized operation. In this way, even in places where the possibility of unexpected objects being present along the travel path must be considered, such as construction sites, pallets can be safely transported with the assistance of the operator.

[0034] As described above, the disclosed pallet transport device 10 comprises a top plate 20 on which a wheeled pallet is placed, and a drive unit provided below the top plate 20, wherein the top plate 20 has rails 21 for the wheels of the pallet, and the pallet can be fixed after the wheels are rotated along the rails 21 and the pallet is placed on it, and the drive unit is characterized by having a sensor 12 for detecting the surrounding conditions and a drive wheel 11 that is driven based on the detection result of the sensor 12. Therefore, it is possible to provide a highly versatile pallet transport device that does not require processing of wheeled pallets and can be moved in the same way as manual transport.

[0035] Furthermore, the rail 21 is formed by a surface lower than the upper surface of the top plate 20, the top plate 20 has two rails 21 along a pair of opposing sides, the drive wheel 11 is positioned between the two rails 21, and the diameter of the drive wheel 11 is greater than the height from the surface on which the drive wheel 11 runs to the surface forming the rail. Therefore, it is possible to provide a pallet transport device that facilitates pallet loading and unloading and has high navigation performance.

[0036] Furthermore, the top plate 20 is substantially rectangular in shape, the two rails 21 are provided along the two long sides of the top plate 20, the drive wheels 11 are provided on each of the two rails near the center of the long sides, the two drive wheels 11 can be controlled to rotate independently, and the sensors 12 are provided on each of the two short sides of the top plate. Therefore, it is possible to provide a pallet transport device in which forward and reverse movement are equivalent.

[0037] Furthermore, by providing swivel casters 13 on each of the two shorter sides of the top plate 20, the safety of tipping over can be improved.

[0038] Furthermore, a rotating member 22 is provided at least one end of the rail 21, and the rotating member 22 can be switched by rotation between a first state in which it functions as a slope connecting the surface on which the drive wheels 11 travel and the surface forming the rail 21, and a second state in which it functions as a wheel stopper that keeps the wheels of the pallet on the rail 21. Therefore, loading, unloading, and securing pallets can be easily done.

[0039] Furthermore, the drive unit may be detachable from the top plate 20, and may autonomously perform positioning and attachment / detachment to the top plate 20. In this configuration, the number of top panels 20 and the number of drive units can be determined independently, enabling flexible operation at a low cost. Furthermore, if the positioning and attachment / detachment of the top plate 20 are performed manually, costs can be further reduced.

[0040] Furthermore, the drive unit has a configuration in which a sensor module including the sensor 12 and a drive wheel module including the drive wheel 11 are connected, and the sensor module and the drive wheel module can be fixed to a top plate of different sizes in a positional relationship that matches the size of the top plate, and the drive unit controls the vehicle's movement based on parameters set according to the size of the top plate. Therefore, it can flexibly accommodate a variety of tabletop sizes at a low cost.

[0041] Furthermore, the pallet transport device 110 of Embodiment 2 is equipped with two rails 121 on the top plate 120, the rails 121 extending in the longitudinal direction of the top plate 120, the drive wheels 111 positioned outside the longitudinal side of the top plate 120, and the drive wheels 111 have a rotation axis perpendicular to the rails 121. Therefore, it is possible to move along the longitudinal direction of the top plate 120 with high driving force.

[0042] Furthermore, the pallet transport device 110 of Embodiment 2 is equipped with four drive wheels 111 corresponding to the four corners of the top plate 120. Furthermore, auxiliary wheels 113 can be provided near the center of the long side of the top plate 120. For example, Mecanum wheels or omnidirectional casters may be provided on the outside of the center of the long side. Alternatively, regular casters may be provided on the inside of the center of the long side. These configurations allow for stable loading of pallets.

[0043] Furthermore, in the pallet transport device 110 of Embodiment 2, the sensor and the control unit that determines the control content of the drive wheel based on the detection result from the sensor can be arranged between the two rails 121. Therefore, the space between the rails can be used effectively, and the device can be made smaller.

[0044] Furthermore, the disclosed pallet transport device determines the control content of the drive wheels based on the detection results from the sensor and drives the drive wheels on the condition that it has received permission from the operator to perform the operation. By operating in this manner, pallets can be safely transported with the assistance of a worker, even in locations where fully autonomous driving is difficult.

[0045] It should be noted that the present invention is not limited to the embodiments described above, and various modifications are included. For example, the embodiments described above are explained in detail to make the present invention easier to understand, and are not necessarily limited to those having all the configurations described. Furthermore, it is possible to replace or add configurations, not just delete them. For example, the rotating member 22 may be provided at one end and a fixed stopper at the other end. Also, the shape of the top plate is not limited to a rectangle and can be designed as appropriate. In addition, any type of swivel caster, such as a ball caster, can be used. Furthermore, instead of the pallet transport device 10 having a ramp, the ramp may be installed on the floor side, and after the worker places the cage trolley 30 on the pallet transport device 10, the work of installing wheel stops between the rail 21 and the wheels 31 may be performed manually. Furthermore, although the above embodiment illustrates a configuration in which the outer edge of the rail 21 is curved upward, the orientation of the wheel 31 may also be restricted by eliminating the curvature of the outer edge of the rail 21 and screwing an L-shaped guide member having the same length as the rail 21 to the rail 21. In such a configuration, even if the distance between the wheels of the trolley 30 or the width of the wheels themselves changes by adjusting the fixing position of the L-shaped guide member, the same member can be used to accommodate the change while maintaining strength. [Explanation of Symbols]

[0046] 10,110: Pallet transport device, 11,111: Drive wheel, 12: Sensor, 13: Swivel caster, 20,120: Top plate, 21,121: Rail, 22: Rotating member, 30: Cage trolley, 31,131: Wheel, 113: Auxiliary wheel, 130: Pallet, 132: Locking mechanism

Claims

1. A top plate on which wheeled pallets are placed, It comprises a drive unit located beneath the top plate, The top plate has rails for the wheels of the pallet, and after the wheels are rotated along the rails and the pallet is placed on it, the pallet can be fixed in place. The drive unit includes a sensor for detecting the surrounding conditions and a drive wheel that is driven based on the detection results from the sensor. The aforementioned top plate is roughly rectangular in shape. The aforementioned top plate is provided with two rails along two opposing longitudinal sides, The diameter of the drive wheel is greater than the height from the surface on which the drive wheel travels to the surface forming the rail. The drive wheel has a rotation axis perpendicular to the rail. A pallet transport device characterized by the following features.

2. A pallet transport device according to claim 1, The rail is formed by a surface lower than the top surface of the top plate. The pallet transport device is characterized in that the drive wheels are arranged between the two rails.

3. A pallet transport device according to claim 2, The drive wheels are provided in pairs near the center of the longitudinal side, corresponding to each of the two rails. The two drive wheels can be controlled to rotate independently. The sensors are provided on each of the two shorter sides of the top plate. A pallet transport device characterized by the following features.

4. A pallet transport device according to claim 3, A pallet transport device characterized by having swivel casters on each of the two shorter sides of the top plate.

5. A pallet transport device according to claim 1, A rotating member is provided at at least one end of the rail, The pallet transport device is characterized in that the rotating member can be switched by rotation between a first state in which it functions as a slope connecting the surface on which the drive wheels travel and the surface forming the rail, and a second state in which it functions as a wheel stopper that keeps the wheels of the pallet on the rail.

6. A pallet transport device according to claim 1, The pallet transport device is characterized in that the drive unit is detachable from the top plate and autonomously performs positioning and attachment / detachment to the top plate.

7. A pallet transport device according to claim 1, The drive unit has a configuration in which a sensor module including the sensor and a drive wheel module including the drive wheel are connected, The sensor module and the drive wheel module can be fixed to top plates of different sizes in a positional relationship that matches the size of the top plate. The drive unit controls the movement based on parameters set according to the size of the top plate. A pallet transport device characterized by the following features.

8. A pallet transport device according to claim 1, The top plate is provided with two of the aforementioned rails, The rail extends in the longitudinal direction of the top plate, The pallet transport device is characterized in that the drive wheels are positioned outside the long side of the top plate.

9. A pallet transport device according to claim 8, A pallet transport device characterized by having four drive wheels attached to the four corners of the top plate.

10. A pallet transport device according to claim 9, A pallet transport device characterized by having auxiliary wheels provided near the center of the long side of the top plate.

11. A pallet transport device according to claim 8, A pallet transport device characterized in that the aforementioned sensor and a control unit that determines the control content of the drive wheel based on the detection result of the aforementioned sensor are arranged between the two rails.

12. A pallet transport device according to claim 1, A pallet transport device characterized by determining the control content of the drive wheel based on the detection results of the aforementioned sensor, and driving the drive wheel on the condition that permission for operation by the operator has been received.

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