Vehicle charging system

Abstract

Provided is a vehicle charging system, wherein a vehicle (2) comprises: a vehicle-side connector (5) that is connected to a charging device (4); a switching device that brings about a connected state in which a power storage device and the vehicle-side connector (5) are electrically connected when the vehicle-side connector (5) is connected to the charging device (4), and brings about a disconnected state in which the electrical connection between the power storage device and the vehicle-side connector (5) is disconnected when the vehicle-side connector (5) is not connected to the charging device (4); a power-receiving unit; and a power supply circuit. The charging device (4) comprises: a charging connector (13) connected to the vehicle-side connector (5); and a power-supplying unit for supplying power to the power-receiving unit. The switching device is configured so as to perform a forced switching operation for switching from the disconnected state to the connected state when the power received by the power-receiving unit is supplied in a state in which the power of the power storage device has been used up.

Description

Vehicle Charging System

[0001] The present invention relates to a vehicle charging system.

[0002] For example, Japanese Patent Laid-Open No. 2021-132524 (Patent Document 1) discloses a technology related to a vehicle charging system. In the following description of the background art, the reference numerals in parentheses refer to those in Patent Document 1.

[0003] The vehicle charging system disclosed in Patent Document 1 includes a vehicle (mobile object 3) and a charging device (charging station 1). The vehicle includes a power receiving terminal (36) and a power storage device (battery 35) connected to the power receiving terminal (36). The power receiving terminal (36) is provided at the rear of the vehicle body. The charging device includes a charging unit (11) that charges the vehicle and a plate unit (13). The charging unit (11) is provided with a charging power source (19) and a power supply terminal (15). In this charging device, when the vehicle moves onto the plate unit (13), the plate unit (13) rotates. As a result, the vehicle is positioned so that the power receiving terminal (36) at the rear of the vehicle faces the power supply terminal (15) of the charging unit (11). When the vehicle then approaches the power supply terminal (15), the power receiving terminal (36) and the power supply terminal (15) are connected. As a result, power is supplied from the charging power source (19) to the power storage device.

[0004] Japanese Patent Application Laid-Open No. 2021-132524

[0005] In the vehicle disclosed in Patent Document 1, when the vehicle-side connector (power receiving terminal 36) connected to the charging device is exposed to the outside, there is a risk of electric shock if an operator comes into contact with the connector. Although not described in Patent Document 1, a possible solution to avoid this situation is to provide a switching device that electrically disconnects the connector from the power storage device except when the vehicle is being charged and electrically connects the connector to the power storage device when charging begins. However, if the power of the power storage device is depleted, the switching device cannot be operated using the power from the power storage device, and charging may not be possible even if the connector is connected to the charging device. In such a situation, it may be necessary to perform a separate task, such as removing the power storage device from the vehicle and directly charging the power storage device, which is time-consuming.

[0006] Therefore, there is a demand for a vehicle charging system that can ensure safety when using the vehicle and can easily charge the battery even when the power of the power storage device is used up.

[0007] The vehicle charging system according to the present disclosure is a vehicle charging system including a vehicle equipped with a power storage device and a charging device that charges the power storage device, wherein the vehicle includes: a vehicle-side connector that is exposed to the outside of the vehicle body and connected to the charging device; a switching device that receives power from the power storage device, and that, when the vehicle-side connector is connected to the charging device, places the power storage device and the vehicle-side connector in an electrically connected state, and when the vehicle-side connector is not connected to the charging device, places the electrical connection between the power storage device and the vehicle-side connector in a disconnected state; a power receiving unit different from the vehicle-side connector; and a power supply circuit that supplies the power received by the power receiving unit to the switching device; and the charging device includes a charging connector that is connected to the vehicle-side connector, and a power supply unit that is connectable to the power receiving unit and supplies power to the power receiving unit, and the switching device is configured to perform a forced switching operation to switch to the connected state if the disconnected state is present, when the power received by the power receiving unit is supplied via the power supply circuit when the power of the power storage device is used up.

[0008] According to this configuration, when the vehicle-side connector is not connected to the charging device, the switching device electrically disconnects the power storage device from the vehicle-side connector, preventing electric shock even if a person comes into contact with the vehicle-side connector exposed to the outside of the vehicle body. Because this switching device operates by receiving power from the power storage device, it cannot switch from the disconnected state to the connected state when the power storage device's power is depleted. However, according to this configuration, when the power supply unit and the power receiving unit are connected when the power storage device's power is depleted, the switching device can perform a forced switching operation using the power supplied from the power supply unit. This electrically connects the power storage device to the vehicle-side connector, so even if charging must be performed from a state in which the power storage device's power is depleted, charging of the power storage device can be started as long as the vehicle-side connector is connected to the charging device. Thus, according to this configuration, the power storage device can be easily charged even when its power is depleted while ensuring safety when using the vehicle.

[0009] Further features and advantages of the vehicle charging system will become apparent from the following description of exemplary, non-limiting embodiments that refer to the drawings.

[0010] A perspective view of a vehicle. A front view schematically showing a state in which the vehicle is in use. A perspective view of a charging device. A perspective view showing a state in which the vehicle and the charging device are connected. A cross-sectional view showing a state in which the vehicle-side connector and the charging connector are connected. A circuit diagram connecting a switching device, a power storage device, a power receiving unit, and a vehicle-side connector of a vehicle. A control block diagram and a control flow diagram. A perspective view schematically showing a connection mechanism of another embodiment. A perspective view schematically showing a holding mechanism of another embodiment.

[0011] Hereinafter, an embodiment of a vehicle charging system will be described with reference to the drawings.

[0012] As shown in FIGS. 1 to 4 , the vehicle charging system 1 includes a vehicle 2 equipped with a power storage device 3 and a charging device 4 that charges the power storage device 3. The vehicle charging system 1 also includes a connection mechanism 40. In this embodiment, the vehicle 2 is an article transport vehicle that transports articles W. In this example, as shown in FIG. 2 , the vehicle 2 transports the articles W in an article transport facility 100. The article transport facility 100 includes a first transport device 8 and a second transport device 7. The article transport facility 100 also has a travel path 50 along which the vehicle 2 travels, which is preset. As shown in FIG. 2 , the first transport device 8 is disposed adjacent to each of the outer sides of the travel path 50. The second transport device 7 is disposed adjacent to the first transport device 8 on the opposite side of the travel path 50. A plurality of containers K are disposed on the second transport device 7. Here, both the first transport device 8 and the second transport device 7 are conveyors.

[0013] The vehicle 2 is configured to travel along the travel path 50 and transport items to a container K on the second conveying device 7. In this example, one of multiple containers K lined up in a row on the conveying surface of the second conveying device 7 (here, a conveyor) is set as the destination. Multiple first conveying devices 8 are arranged to correspond to the multiple containers K. The vehicle 2 stops on the travel path 50 at a position corresponding to the set container K and transfers the item W to the first conveying device 8. The first conveying device 8 transports the item W toward the second conveying device 7 (in the direction of the arrow in FIG. 2 ). The item W is then loaded from the first conveying device 8 into the container K on the second conveying device 7. In this example, as shown in FIGS. 3 and 4 , a charging area 10 is set in the item conveying equipment 100. A charging device 4 is arranged in the charging area 10. The vehicle 2 can travel along the travel path 50 to move to the charging area 10. The vehicle 2 moves to the charging area 10 as needed. The vehicle 2 stops at a position adjacent to the charging device 4 and is charged by the charging device 4. A specific charging configuration will be described in detail later. In the article conveying facility 100, multiple vehicles 2 can travel along a travel route 50. In addition, in the article conveying facility 100, the travel route 50 can be set arbitrarily. For example, the travel route 50 can be a combination of straight and curved lines. The travel route 50 can also be provided on multiple floors. Naturally, the charging area 10 can also be located at any location.

[0014] In the following description, the direction in which the vehicle 2 and the charging device 4 are adjacent to each other is referred to as the first direction X, and the direction perpendicular to the first direction X when viewed from above is referred to as the second direction Y. One side of the first direction X is referred to as the first direction first side X1, and the other side is referred to as the first direction second side X2. In this example, the first direction X is the same as the traveling direction of the vehicle 2, and the second direction Y is the same as the width direction of the vehicle 2. The first direction first side X1 is the front side in the traveling direction of the vehicle 2, and the first direction second side X2 is the rear side in the traveling direction of the vehicle 2.

[0015] As shown in Figures 1 and 7, the vehicle 2 includes a traveling device 20 and a transfer device 30. The vehicle 2 also includes a car body 31 and an electricity storage device 3. In this example, the traveling device 20 includes wheels 24 (here, a plurality of wheels 24), a drive mechanism (not shown) that drives the wheels 24, and a bogie body 22. The drive mechanism is configured to drive at least one of the plurality of wheels 24. In this example, the drive mechanism is connected to the electricity storage device 3. This allows the drive mechanism to obtain power to rotate the wheels 24. The wheels 24 and the drive mechanism are supported by the bogie body 22.

[0016] The car body 31 is supported from below by the carriage main body 22. The car body 31 includes a first cover portion 25 facing the first direction X and a second cover portion 23 facing the second direction Y. A storage space capable of accommodating devices and the like is formed inside the car body 31. The transfer device 30 includes a placement portion 26 on which an item W is placed, and a turning mechanism 32 that turns the placement portion 26 around either the first axis A1 or the second axis A2. The turning mechanism 32 is housed in the storage space of the car body 31. The placement portion 26 is disposed above the car body 31 and is supported by the turning mechanism 32. The turning mechanism 32 is connected to the power storage device 3. This allows the turning mechanism 32 to obtain power to turn the placement portion 26. Here, the first axis A1 and the second axis A2 are arranged along the first direction X and spaced apart from each other in the second direction Y. Specifically, the first axis A1 is arranged at one end of the mounting portion 26 in the second direction Y, and the second axis A2 is arranged at the other end of the mounting portion 26 in the second direction Y. As shown in FIG. 2 , the turning mechanism 32 includes a cam mechanism. The cam mechanism causes the mounting portion 26 to turn around the first axis A1 or the second axis A2 and assume an inclined position. As a result, the article W placed on the upper surface (mounting surface 26 a) of the mounting portion 26 slides down the mounting surface 26 a and is placed on the conveying surface of the first conveying device 8. The power storage device 3 includes a battery 3 a. The power storage device 3 is stored in a storage area of ​​the vehicle body 31. In the example of Figure 1, the top surface of the first cover part 25 (here, the first cover part 25 on the second side X2 of the first direction) is provided with a display part 27 that displays the remaining charge of the battery 3a and a stop button 28 for manually stopping the vehicle 2.

[0017] 1 and 7 , the vehicle 2 includes a vehicle-side connector 5, a switching device 6, a power receiving unit 11 different from the vehicle-side connector 5, and a power supply circuit 12. The vehicle 2 further includes a vehicle-side connection unit 17 and a control device 37 that controls each device of the vehicle 2. The control device 37 includes, for example, a processor such as a microcomputer, peripheral circuits such as a memory, and the like. Each function is realized by cooperation between these pieces of hardware and a program executed on a processor such as a computer.

[0018] As shown in FIGS. 1 and 5 , the vehicle-side connector 5 is exposed to the outside of the vehicle body 31 and is connected to the charging device 4. In this embodiment, the vehicle-side connector 5 is provided on the first cover portion 25 on the first side X1 in the first direction (here, the first cover portion 25 on the forward side in the traveling direction of the vehicle body 31). The vehicle-side connector 5 is configured to be connectable to a charging connector 13 included in the charging device 4 ( FIG. 5 ). As shown in FIG. 6 , the vehicle-side connector 5 is connected to the power storage device 3 (battery 3a) and the switching device 6. In the example shown in FIGS. 1 and 5 , the vehicle-side connector 5 has a concave shape in the first cover portion 25 that is recessed toward the second side X2 in the first direction and opens toward the first side X1 in the first direction. Therefore, when a person looks inside, the connection terminals of the vehicle-side connector 5, members supporting the connection terminals, and the like can be seen. When the charging connector 13 is inserted through the opening, the connection terminals of the vehicle-side connector 5 and the charging connector 13 come into contact with each other, thereby enabling electrical connection between these connectors. The battery 3 a is configured to be charged by the charging device 4 when the vehicle-side connector 5 and the charging connector 13 are electrically connected.

[0019] As shown in FIGS. 5 and 7 , the vehicle-side connection unit 17 operates by receiving power from the power storage device 3. The vehicle-side connection unit 17 is configured to be connectable to the charging-side connection unit 18 of the charging device 4. In this example, the vehicle-side connection unit 17 operates by receiving power from the power storage device 3 and functions as a communication device capable of communicating with the charging device 4. Specifically, the vehicle-side connection unit 17 communicates with the charging-side connection unit 18. In the example of FIGS. 1 and 5 , the vehicle-side connection unit 17 is disposed on a surface of the bogie body 22 facing the first side X1 in the first direction. More specifically, the vehicle-side connection unit 17 is disposed below the vehicle-side connector 5 so as to overlap with the vehicle-side connector 5 in the second direction Y. Here, the vehicle-side connection unit 17 is configured to be able to communicate with the charging-side connection unit 18 via infrared communication. Note that the vehicle-side connection unit 17 and the charging-side connection unit 18 may be configured to be able to communicate via wireless LAN communication, short-range wireless communication, wired connection, or the like.

[0020] The power receiving unit 11 is configured to be able to receive power from the power supply unit 14 of the charging device 4. As shown in FIG. 6 , the power receiving unit 11 is connected to the switching device 6 via a power supply circuit 12. In this embodiment, as shown in FIG. 4 , the power receiving unit 11 and the power supply unit 14 are connected by a connection mechanism 40. The power receiving unit 11 includes a power receiving connector 11a that is connected to a tip end 9a of a connection cable 9 (described below) that is provided in the connection mechanism 40. In this example, as shown in FIG. 1 , the power receiving unit 11 is provided inside the vehicle body 31. In the illustrated example, an opening is formed in the upper surface of the first cover portion 25 on the first side X1 in the first direction. When the tip end 9a of the connection cable 9 is inserted into the opening, the power receiving connector 11a (connection terminal) and the tip end 9a are fitted together. In this embodiment, the power receiving unit 11 and the power supply unit 14 on the charging device 4 side are connected to each other by the connection cable 9 , so that the power receiving unit 11 can receive power from the power supply unit 14 .

[0021] 6 , the power supply circuit 12 supplies the power received by the power receiving unit 11 to the switching device 6. In this embodiment, the power supply circuit 12 is a circuit that connects the power receiving unit 11 and the switching device 6. The power received by the power receiving unit 11 from the power supply unit 14 is supplied to the switching device 6 via the power supply circuit 12.

[0022] As shown in FIG. 6 , the switching device 6 receives power from the power storage device 3 and operates to electrically connect the power storage device 3 and the vehicle-side connector 5 when the vehicle-side connector 5 is connected to the charging device 4, and electrically disconnects the power storage device 3 and the vehicle-side connector 5 when the vehicle-side connector 5 is not connected to the charging device 4. In this embodiment, the switching device 6 is arranged to connect the vehicle-side connector 5 and the power storage device 3 (battery 3 a). More specifically, the switching device 6 is arranged to connect one terminal of the vehicle-side connector 5 to the power storage device 3. In other words, one terminal of the vehicle-side connector 5 is connected to the power storage device 3 via the switching device 6. In this example, the switching device 6 is a contact relay. Note that the switching device 6 may include various types of contactless relays instead of a contact relay. Here, in this example, the control device 37 includes a vehicle-side connection determination unit 33. The vehicle-side connection determination unit 33 determines whether the vehicle-side connector 5 is connected to the charging connector 13 based on the connection (communication) between the vehicle-side connection unit 17 and the charging-side connection unit 18. When the vehicle-side connection determination unit 33 determines that the vehicle-side connector 5 is connected to the charging connector 13, the control device 37 controls the switching device 6 to switch the switch from an OFF state to an ON state. This electrically connects the power storage device 3 and the vehicle-side connector 5 (connected state). When the vehicle-side connection determination unit 33 determines that the vehicle-side connector 5 is not connected to the charging connector 13, the control device 37 controls the switching device 6 to switch the switch from an ON state to an OFF state. This disconnects the electrical connection between the power storage device 3 and the vehicle-side connector 5 (disconnected state). Therefore, when the vehicle 2 is being charged by the charging device 4 in the charging area 10, the power storage device 3 and the vehicle-side connector 5 are electrically connected. On the other hand, in other states, the electrical connection between the power storage device 3 and the vehicle-side connector 5 is disconnected. Therefore, even if a person accidentally touches the vehicle-side connector 5 when charging is not being performed by the charging device 4, electric shock can be prevented.

[0023] The switching device 6 is configured to perform a forced switching operation to switch the disconnected state to the connected state when power received by the power receiving unit 11 is supplied via the power supply circuit 12 in a state where the power storage device 3 is depleted (hereinafter, sometimes referred to as a "starved state"). Here, the switching device 6 operates by receiving power from the power storage device 3 as described above. Therefore, when the power storage device 3 is depleted, even if the vehicle-side connector 5 and the charging connector 13 are connected, the switch of the switching device 6 does not turn on. That is, the switching device 6 cannot switch from the disconnected state to the connected state. Therefore, the charging device 4 and the vehicle-side connector 5 are not electrically connected, and the charging device 4 cannot charge the power storage device 3. On the other hand, when power is supplied from the power receiving unit 11 to the switching device 6 via the power supply circuit 12 in the starved state and a voltage equal to or higher than a certain level is input, the switch of the switching device 6 switches from the off state to the on state. This allows the power storage device 3 and the vehicle-side connector 5 to be electrically connected (connected). In addition, the "state in which the power of the storage device 3 has been used up (depleted state)" does not only mean a state in which all the power of the battery 3a has been used up, but also includes, for example, a state in which the remaining amount of power in the battery 3a is such that control by the control device 37 is not performed, and also includes a state in which the remaining amount of power in the battery 3a is less than the amount required for the operation of the switching device 6.

[0024] As shown in FIGS. 3 , 4 , and 7 , the charging device 4 includes a charging connector 13 connected to the vehicle-side connector 5 and a power supply unit 14 connectable to the power receiving unit 11 and supplying power to the power receiving unit 11. The charging device 4 also includes a connection determination unit 19 that determines whether the charging connector 13 is connected to the vehicle-side connector 5 based on the connection between the charging-side connection unit 18 and the vehicle-side connection unit 17, and a manually operable charging start switch 21. The charging device 4 also includes a holding mechanism 81 that holds the vehicle 2 so that the vehicle-side connector 5 and the charging connector 13 do not separate when the vehicle-side connector 5 and the charging connector 13 are connected. In this embodiment, the charging device 4 also includes a power supply unit 16 that is directly or indirectly connected to an external commercial power source and a control unit 15 that controls each component of the charging device 4. The control unit 15 includes, for example, a processor such as a microcomputer, peripheral circuits such as a memory, and the like. Each function is realized by cooperation between these hardware components and a program executed on the processor of a computer or the like. In this example, the connection determination unit 19 determines whether the charging connector 13 is connected to the vehicle-side connector 5 based on communication between the charging-side connection unit 18 and the vehicle-side connection unit 17 .

[0025] In this example, the charging device 4 includes a housing 101. As shown in FIG. 3 , the housing 101 is oriented in the up-down direction, the first direction X, and the second direction Y. The charging connector 13 and the charging-side connection portion 18 are provided on a surface of the housing 101 facing the first direction second side X2 (the side on which the vehicle 2 is disposed). The charging connector 13 is disposed at a position corresponding to the vehicle-side connector 5 to be connected. The charging connector 13 is also provided so as to be exposed to the outside of the housing 101. The charging-side connection portion 18 is also disposed at a position corresponding to the vehicle-side connection portion 17. In this example, the charging-side connection portion 18 functions as a communication device capable of communicating with the vehicle-side connection portion 17. The charging connector 13 has a convex shape that protrudes from the housing 101 toward the first direction second side X2. As shown in FIG. 5 , the convex charging connector 13 is inserted relatively into the concave vehicle-side connector 5, and the tip of the connection terminal of the charging connector 13 abuts against the connection terminal of the vehicle-side connector 5, thereby enabling these connectors to be electrically connected to each other.

[0026] Here, the connection mechanism 40 is configured to be able to connect the power receiving unit 11 and the power supply unit 14 when the distance between the vehicle connector 5 and the charging connector 13 is equal to or less than a specified length. In this example, the "specified length" is a length that prevents a person's finger from entering the gap between the vehicle connector 5 and the charging connector 13 (set to 1 cm in this example, but is not limited to this). The connection mechanism 40 is configured to be unable to connect the vehicle connector 5 and the charging connector 13 when the distance between the vehicle connector 5 and the charging connector 13 is greater than the specified length. In this embodiment, as shown in FIGS. 3 to 5 , the connection mechanism 40 includes the above-described connection cable 9 that connects the power receiving unit 11 and the power supply unit 14. The connection mechanism 40 is configured to be unable to connect the power receiving unit 11 and the power supply unit 14 via the connection cable 9 when the distance between the vehicle connector 5 and the charging connector 13 is greater than the specified distance (here, 1 cm).

[0027] The power supply unit 14 is disposed inside the housing 101. The connection cable 9 is provided in the charging device 4 while connected to the power supply unit 14. In this example, a through hole 14a is formed in the top surface of the housing 101. The connection cable 9, which is connected to the power supply unit 14, is disposed so as to be exposed to the outside of the housing 101 through the through hole 14a. In this manner, one end of the connection cable 9 is always connected to the power supply unit 14. The length of the connection cable 9 is set so that the power receiving unit 11 and the power supply unit 14 can be connected when the vehicle-side connector 5 and the charging connector 13 are connected, and so that a person's finger cannot be inserted into the gap between the vehicle-side connector 5 and the charging connector 13 when the power receiving unit 11 and the power supply unit 14 are connected. Specifically, the length of the connection cable 9 is set so that the power receiving unit 11 and the power supply unit 14 cannot be connected when the gap between the vehicle-side connector 5 and the charging connector 13 is large enough for a person's finger to fit through the gap. In other words, the length of connection cable 9 is set to a length that makes it impossible to connect power receiving unit 11 and power supply unit 14 when a human finger or something larger than a human finger is inserted in the gap between vehicle-side connector 5 and charging connector 13. Therefore, the operation of connecting power receiving unit 11 and power supply unit 14 with connection cable 9 is performed after the operation of connecting vehicle-side connector 5 and charging connector 13 is completed.

[0028] The connection determination unit 19 is provided in the control unit 15. When the connection determination unit 19 determines that the charging connector 13 is connected to the vehicle-side connector 5 based on communication between the charging-side connection unit 18 and the vehicle-side connection unit 17, the control unit 15 controls the power supply unit 16 to supply power to the vehicle-side connector 5 via the charging connector 13. In this example, the vehicle 2 autonomously travels along a travel route 50. When the control device 37 of the vehicle 2 determines that the remaining power of the battery 3a of the vehicle 2 is, for example, less than 30% of the total, the control device 37 causes the vehicle 2 to travel to a charging area 10. The control device 37 of the vehicle 2 stops the vehicle 2 at a position where the vehicle-side connector 5 is connected to the charging connector 13. When the control unit 15 of the charging device 4 determines that the charging connector 13 is connected to the vehicle-side connector 5 as described above, the control unit 15 automatically starts supplying power to the vehicle-side connector 5. Note that the remaining power used as the criterion for the determination is not limited to less than 30% of the total capacity and may be, for example, less than 40% of the total capacity, and this percentage can be changed appropriately as needed. The charging start switch 21 is a switch for manually starting power supply to the vehicle-side connector 5 (FIG. 7). In this example, the charging start switch 21 is provided on a surface of the housing 101 facing the first side X1 in the first direction (not shown), but may be provided on another surface.

[0029] As shown in FIGS. 3 and 4 , the holding mechanism 81 includes a holding portion 81a and a position change portion 81b. In this example, the holding mechanism 81 is attached to the top surface of the housing 101. Here, the holding portion 81a is an L-shaped bracket. The position change portion 81b is a hinge. The holding portion 81a is attached to the top surface of the housing 101 via the position change portion 81b. The position change portion 81b is configured to be position-changeable between a protruding position in which the holding portion 81a protrudes from the housing 101 toward the second side X2 in the first direction and a protrusion-released position in which the holding portion 81a is disposed on the top surface of the housing 101 by rotating the position change portion 81b. As shown in FIG. 4 , when the vehicle 2 is connected to the charging device 4, i.e., when the vehicle-side connector 5 and the charging connector 13 are connected, the holding portion 81a is in the protruding position, and the bracket engages with the groove 29 formed in the vehicle 2. The groove 29 is a gap between the upper part of the first cover part 25 (here, the first cover part 25 on the first side X1 in the first direction) and the mounting part 26 of the transfer device 30, and is formed in a groove shape along the second direction Y. In this way, the holding mechanism 81 can lock the vehicle 2 to the charging device 4 by utilizing the gap between the first cover part 25 and the mounting part 26.

[0030] The charging mechanism in the vehicle charging system 1 will be described in more detail below.

[0031] 8 , the charging device 4 supplies power to the charging connector 13 when the connection determination unit 19 determines that the charging connector 13 is connected to the vehicle-side connector 5. In this example, when the connection determination unit 19 determines that the charging connector 13 is connected to the vehicle-side connector 5 (S01: Yes), the control unit 15 controls the power supply unit 16 to supply power to the charging connector 13 (S03). As described above, when the charging connector 13 is electrically connected to the vehicle-side connector 5 of the vehicle 2 that is not in a depleted state, the charging-side connection unit 18 and the vehicle-side connection unit 17 are able to communicate with each other. Therefore, the connection determination unit 19 can appropriately determine that the charging connector 13 is connected to the vehicle-side connector 5. Therefore, when the control unit 15 recognizes the connection, the power supply unit 16 supplies power to the charging connector 13, thereby starting power supply to the power storage device 3 of the vehicle 2. Note that the control unit 15 may start supplying power to the charging connector 13 based on the connection information acquired from the charging-side connection unit 18, even before the charging connector 13 and the vehicle-side connector 5 are completely connected. Furthermore, the charging device 4 is configured not to supply power to the charging connector 13 when the connection determination unit 19 has not determined that the charging connector 13 is connected to the vehicle-side connector 5. Furthermore, even when the connection determination unit 19 has not determined that the charging connector 13 is connected to the vehicle-side connector 5, if the charging start switch 21 is operated while the power supply unit 14 is supplying power to the power receiving unit 11, the charging device 4 supplies power to the charging connector 13. In this example, when the connection determination unit 19 has determined that the charging connector 13 is not connected to the vehicle-side connector 5 (S01: No), the control unit 15 determines whether power is being supplied from the power supply unit 14 to the power receiving unit 11 (S02). Then, when the control unit 15 determines that power is being supplied from the power supply unit 14 to the power receiving unit 11 (S02: Yes), and the charging start switch 21 is pressed, the control unit 15 controls the power supply unit 16 to supply power to the charging connector 13 (S03).

[0032] For example, when a vehicle 2 in a depleted state is stopped on a travel route 50, an operator connects the vehicle 2 to the charging device 4. Specifically, as shown in FIGS. 4 , 5 , and 7 , the vehicle-side connector 5 and the charging connector 13 are connected. However, as described above, in the depleted state, the switching device 6 is not switched on and remains in a disconnected state, so that power supply from the charging device 4 to the power storage device 3 is not started. Note that in the depleted state, the vehicle-side connection unit 17 does not function, so the charging-side connection unit 18 cannot communicate with the vehicle-side connection unit 17. Therefore, even if the vehicle-side connector 5 and the charging connector 13 are connected, the connection determination unit 19 determines that they are not connected (or may determine that the connection state is unknown). When the tip end 9 a of the connection cable 9 is connected to the power receiving unit 11 (power receiving connector 11 a) of the vehicle 2, power is supplied from the power supply unit 16 of the charging device 4 to the switching device 6 via the power supply unit 14, the connection cable 9, the power receiving unit 11, and the power supply circuit 12. This switches the switch of the switching device 6 from the off state to the on state, electrically connecting the vehicle-side connector 5 and the charging device 4 (battery 3a), and when the charging start switch 21 is operated, charging of the charging device 4 begins. When power is supplied using the connection cable 9, it is desirable to supply power not only to the switching device 6 but also to the vehicle-side connection unit 17. This enables communication between the charging-side connection unit 18 and the vehicle-side connection unit 17, and the control unit 15 can recognize the connection between the vehicle-side connector 5 and the charging connector 13, and can appropriately start charging of the charging device 4.

[0033] Other Embodiments (1) In the above embodiment, the vehicle 2 is described as an article transport vehicle that autonomously travels along the travel route 50, but the present invention is not limited to this. The vehicle 2 may be, for example, a rail-guided vehicle (including an overhead transport vehicle) that travels while being guided by a rail to transport the article W. Furthermore, the vehicle 2 may not be intended to transport the article W.

[0034] (2) In the above embodiment, the charging device 4 is configured to supply power to the charging connector 13 when the charging start switch 21 is operated while the power supply unit 14 is supplying power to the power receiving unit 11, even if the connection determination unit 19 has not determined that the charging connector 13 is connected to the vehicle-side connector 5. However, the present invention is not limited to this. The charging device 4 can also be configured to automatically supply power to the charging connector 13 when the power supply unit 14 supplies power to the power receiving unit 11 and the charging connector 13 is thereby electrically connected to the vehicle-side connector 5, even without operating the charging start switch 21. In this case, the charging device 4 does not need to include the charging start switch 21. Furthermore, in the above embodiment, the connection determination unit 19 is configured to determine whether the charging connector 13 is connected to the vehicle-side connector 5 based on communication between the charging-side connection unit 18 and the vehicle-side connection unit 17. However, the present invention is not limited to this. For example, charging-side connection unit 18 and vehicle-side connection unit 17 may each be a connection terminal, and connection determination unit 19 may determine that charging connector 13 is connected to vehicle-side connector 5 when they come into contact with each other. Alternatively, charging-side connection unit 18 may include a button, and vehicle-side connection unit 17 may include a member for pressing the button, and connection determination unit 19 may determine that charging connector 13 is connected to vehicle-side connector 5 when the member of vehicle-side connection unit 17 presses the button of charging-side connection unit 18. Alternatively, charging-side connection unit 18 may function as a light-projecting unit that projects laser light, and vehicle-side connection unit 17 may function as a light-receiving unit that receives the laser light, and connection determination unit 19 may determine that charging connector 13 is connected to vehicle-side connector 5 when vehicle-side connection unit 17 receives the laser light.

[0035] (3) In the above embodiment, the connection mechanism 40 is configured to connect the power receiving unit 11 and the power supply unit 14 when the distance between the vehicle connector 5 and the charging connector 13 is equal to or less than a specified length. However, the present invention is not limited to this. The connection mechanism 40 may be configured to connect the power receiving unit 11 and the power supply unit 14 when the vehicle connector 5 and the charging connector 13 are connected.

[0036] (4) In the above embodiment, the connection cable 9 is provided in the charging device 4 while connected to the power supply unit 14. However, this is not limiting. The connection cable 9 may be fixed to the power supply unit 14 or may be configured to be detachable from the power receiving unit 11 and the power supply unit 14. A spare connection cable 9 may be accommodated inside the charging device 4. In the above embodiment, the connection mechanism 40 includes the connection cable 9, and the length of the connection cable 9 is set to a length that prevents connection between the power receiving unit 11 and the power supply unit 14 when the gap between the vehicle-side connector 5 and the charging connector 13 is large enough for a person's finger to fit in the gap. However, this is not limiting. As shown in FIG. 9 , the connection mechanism 40 preferably further includes a cover 41 that covers the power receiving connector 11a in addition to the connection cable 9. Here, the cover 41 is configured to be positionally changeable between a position (closed position) in which it covers the power receiving connector 11a from above and a position (open position) in which it does not cover the power receiving connector 11a from above. The cover 41 is preferably configured to be in the closed position when the distance between the vehicle connector 5 and the charging connector 13 is greater than a specified length, and to be positionally changeable from the closed position to the open position when the distance between the vehicle connector 5 and the charging connector 13 is equal to or shorter than the specified length. Naturally, when the cover 41 is in the closed position, the tip 9a of the connection cable 9 cannot be connected to the power receiving connector 11a. On the other hand, when the cover 41 is in the open position, the tip 9a of the connection cable 9 can be connected to the power receiving connector 11a. Therefore, unlike the above embodiment, when a forced switching operation is performed, it is possible to prevent a person from touching the vehicle connector 5 or the charging connector 13 and receiving an electric shock, regardless of the length of the connection cable 9.

[0037] (5) In the above embodiment, the holding mechanism 81 has been described as including a holding portion 81a and an attitude change portion 81b that engage using the groove 29 of the vehicle 2. However, this is not limiting. The holding mechanism 81 may be, for example, a mechanism for positioning the vehicle 2 at a stopping position in the charging area 10 or a mechanism for locking the rotation of the wheels 24. Furthermore, in a configuration in which the holding mechanism 81 includes a holding portion 81a and an attitude change portion 81b that engage using the groove 29 of the vehicle 2, as shown in FIG. 10 , the holding portion 81a may include a first plate-shaped portion 87 and a second plate-shaped portion 88. In this example, the first plate-shaped portion 87 and the second plate-shaped portion 88 are integrally formed. The first plate-shaped portion 87 is a plate-shaped member fixed to the attitude change portion 81b. The second plate-shaped portion 88 is a plate-shaped member that is inserted into the groove 29 of the vehicle 2 when the attitude of the first plate-shaped portion 87 is changed. When the first plate-shaped portion 87 is placed on the upper surface of the charging device 4, the second plate-shaped portion 88 is disposed so as to protrude upward relative to the surface of the first plate-shaped portion 87. In the illustrated example, the second plate-shaped portion 88 is formed by cutting, bending, or the like, a single flat plate (sheet metal) from which the first plate-shaped portion 87 is formed. Therefore, a through hole is formed in the first plate-shaped portion 87. In this example, the position-changing portion 81b is a torque hinge. An operator can use the portion of the first plate-shaped portion 87 where the through hole is formed to rotate the first plate-shaped portion 87 and insert the second plate-shaped portion 88 into the groove portion 29.

[0038] (6) Note that the configurations disclosed in the above-described embodiments can be applied in combination with configurations disclosed in other embodiments (including combinations of embodiments described as other embodiments) as long as no contradictions arise. Regarding other configurations, the embodiments disclosed in this specification are merely examples in all respects. Therefore, various modifications can be made as appropriate within the scope of the present disclosure.

[0039] Summary of the Above-described Embodiments The following provides a summary of the above-described vehicle charging system.

[0040] The vehicle charging system according to the present disclosure is a vehicle charging system including a vehicle equipped with a power storage device and a charging device that charges the power storage device, wherein the vehicle includes: a vehicle-side connector that is exposed to the outside of the vehicle body and connected to the charging device; a switching device that receives power from the power storage device, and that, when the vehicle-side connector is connected to the charging device, places the power storage device and the vehicle-side connector in an electrically connected state, and when the vehicle-side connector is not connected to the charging device, places the electrical connection between the power storage device and the vehicle-side connector in a disconnected state; a power receiving unit different from the vehicle-side connector; and a power supply circuit that supplies the power received by the power receiving unit to the switching device; and the charging device includes a charging connector that is connected to the vehicle-side connector, and a power supply unit that is connectable to the power receiving unit and supplies power to the power receiving unit, and the switching device is configured to perform a forced switching operation to switch to the connected state if the disconnected state is present, when the power received by the power receiving unit is supplied via the power supply circuit when the power of the power storage device is used up.

[0041] According to this configuration, when the vehicle-side connector is not connected to the charging device, the switching device electrically disconnects the power storage device from the vehicle-side connector, preventing electric shock even if a person comes into contact with the vehicle-side connector exposed to the outside of the vehicle body. Because this switching device operates by receiving power from the power storage device, it cannot switch from the disconnected state to the connected state when the power storage device's power is depleted. However, according to this configuration, when the power supply unit and the power receiving unit are connected when the power storage device's power is depleted, the switching device can perform a forced switching operation using the power supplied from the power supply unit. This electrically connects the power storage device to the vehicle-side connector, so even if charging must be performed from a state in which the power storage device's power is depleted, charging of the power storage device can be started as long as the vehicle-side connector is connected to the charging device. Thus, according to this configuration, the power storage device can be easily charged even when its power is depleted while ensuring safety when using the vehicle.

[0042] Here, the vehicle includes a vehicle-side connection unit that operates by receiving power from the power storage device, and the charging device includes a charging-side connection unit connected to the vehicle-side connection unit, a connection determination unit that determines whether the charging connector is connected to the vehicle-side connector based on the connection between the vehicle-side connection unit and the charging-side connection unit, and a charging start switch that can be operated by a human, and the charging device is configured to supply power to the charging connector when the connection determination unit determines that the charging connector is connected to the vehicle-side connector, and not to supply power to the charging connector when the connection determination unit does not determine that the charging connector is connected to the vehicle-side connector, and further preferably, even when the connection determination unit does not determine that the charging connector is connected to the vehicle-side connector, supply power to the charging connector when the charging start switch is operated while the power supply unit is supplying power to the power receiving unit.

[0043] According to this configuration, when it is determined based on the determination by the connection determination unit that the charging connector is connected to the vehicle-side connector, power is supplied from the charging device to the charging connector, so that power can be supplied appropriately from the charging device to the vehicle-side connector as needed. Furthermore, according to this configuration, even when the vehicle-side connection unit is not operating because the power storage device is out of power, and the connection determination unit cannot determine that the charging connector is connected to the vehicle-side connector, the power storage device can be easily charged by operating the charging start switch.

[0044] Furthermore, in the configuration in which the forced switching operation is performed, a connection mechanism is provided that can connect the power receiving unit and the power supply unit when the distance between the vehicle-side connector and the charging connector is equal to or less than a specified length, and it is preferable that the power supply unit supplies power to the power receiving unit when connected to the power receiving unit by the connection mechanism.

[0045] According to this configuration, the connection mechanism can connect the power receiving unit and the power supply unit when the distance between the vehicle-side connector and the charging connector is less than a specified length, thereby preventing people from accidentally touching the vehicle-side connector or the charging connector and receiving an electric shock when a forced switching operation is performed.

[0046] Furthermore, in a configuration in which the above-mentioned forced switching operation is performed, it is preferable that the connection mechanism includes a connection cable that connects the power receiving unit and the power supply unit, and is configured such that the power receiving unit and the power supply unit cannot be connected by the connection cable when the distance between the vehicle-side connector and the charging connector is greater than the specified distance.

[0047] According to this configuration, the forced switching operation can be easily performed by connecting the power receiving unit and the power supply unit with a connection cable. Furthermore, if the distance between the vehicle-side connector and the charging connector is greater than the specified distance, the power receiving unit and the power supply unit cannot be connected with the connection cable. Therefore, the forced switching operation can be performed appropriately while preventing a person from touching the vehicle-side connector or the charging connector and getting an electric shock.

[0048] Preferably, the charging device further includes a holding mechanism that holds the vehicle so that the vehicle-side connector and the charging connector do not separate when the vehicle-side connector and the charging connector are connected to each other.

[0049] According to this configuration, even if the power of the storage device is used up and the vehicle cannot brake to prevent itself from moving, the vehicle-side connector and the charging connector can remain connected, allowing the storage device to continue charging appropriately.

[0050] It is sufficient for the vehicle charging system according to the present disclosure to achieve at least one of the above-described effects.

[0051] REFERENCE SIGNS LIST 1: Vehicle charging system 2: Vehicle 3: Power storage device 4: Charging device 5: Vehicle-side connector 6: Switching device 9: Connection cable 9a: Tip 11: Power receiving unit 11a: Power receiving connector 12: Power supply circuit 13: Charging connector 14: Power supply unit 17: Vehicle-side connection unit 18: Charging-side connection unit 19: Connection determination unit 21: Charging start switch 31: Vehicle body 81: Holding mechanism

Claims

1. A vehicle charging system comprising: a vehicle equipped with a power storage device; and a charging device that charges the power storage device, wherein the vehicle comprises: a vehicle-side connector that is exposed to the outside of the vehicle body and connected to the charging device; a switching device that operates by receiving power from the power storage device and that, when the vehicle-side connector is connected to the charging device, places the power storage device and the vehicle-side connector in an electrically connected state, and when the vehicle-side connector is not connected to the charging device, places the electrical connection between the power storage device and the vehicle-side connector in a disconnected state; a power receiving unit different from the vehicle-side connector; and a power feeding circuit that supplies the power received by the power receiving unit to the switching device, wherein the charging device comprises: a charging connector that is connected to the vehicle-side connector; and a power feeding unit that is connectable to the power receiving unit and feeds power to the power receiving unit, wherein the switching device is configured to perform a forced switching operation to switch to the connected state if the disconnected state is present when power received by the power receiving unit is supplied via the power feeding circuit when the power of the power storage device has been used up.

2. The vehicle charging system according to claim 1, wherein the vehicle includes a vehicle-side connection unit that operates by receiving power from the power storage device, and the charging device includes a charging-side connection unit connected to the vehicle-side connection unit, a connection determination unit that determines whether the charging connector is connected to the vehicle-side connector based on the connection between the vehicle-side connection unit and the charging-side connection unit, and a charging start switch that can be operated by a human, and the charging device is configured to supply power to the charging connector when the connection determination unit determines that the charging connector is connected to the vehicle-side connector, and not to supply power to the charging connector when the connection determination unit does not determine that the charging connector is connected to the vehicle-side connector, and further, even when the connection determination unit does not determine that the charging connector is connected to the vehicle-side connector, if the charging start switch is operated while power is being supplied to the power receiving unit by the power supply unit, the charging device supplies power to the charging connector.

3. A vehicle charging system as described in claim 1 or 2, further comprising a connection mechanism that can connect the power receiving unit and the power supply unit when the distance between the vehicle-side connector and the charging connector is equal to or less than a specified length, and wherein the power supply unit supplies power to the power receiving unit when connected to the power receiving unit by the connection mechanism.

4. The vehicle charging system described in claim 3, wherein the connection mechanism includes a connection cable that connects the power receiving unit and the power supply unit, and is configured such that the power receiving unit and the power supply unit cannot be connected by the connection cable when the distance between the vehicle-side connector and the charging connector is greater than the specified distance.

5. A vehicle charging system as described in claim 1 or 2, wherein the charging device is provided with a holding mechanism that holds the vehicle so that the vehicle-side connector and the charging connector do not separate when the vehicle-side connector and the charging connector are connected.

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