JP2023161282A - charging system - Google Patents

Abstract

To provide a charging system in which a contact state between a power reception unit and a power supply unit can be reliably detected without any sensor or switch.SOLUTION: A charging system 10 includes an electric travel body including a power reception unit 19, and a charging device 12 including a power supply unit 32 that can contact the power reception unit 19. The electric travel body includes a travel motor 17, an on-vehicle controller 25 that controls the travel motor 17, and a power storage device that can be charged via the power reception unit 19. The power supply unit 32 includes an urge member that can advance and retract in accordance with movement of the electric travel body when the power reception unit 19 and the power supply unit 32 contact each other, and that urges the power supply unit 32 to a direction to contact the power reception unit 19. The controller controls the travel motor 17 to stop the electric travel body to the charging device 12 when the torque of the travel motor 17 is equal to or greater than a threshold after the power reception unit 19 and the power supply unit 32 contact.SELECTED DRAWING: Figure 1

Description

The present invention relates to a charging system that includes a traveling body including a power receiving section and a charging device including a power feeding section connectable to the power receiving section.

As a conventional technique of a charging system, for example, an automatic charging device for an unmanned vehicle disclosed in Patent Document 1 is known. In the automatic charging device for an unmanned vehicle disclosed in Patent Document 1, the unmanned vehicle is provided with positive and negative charging terminals on the unmanned vehicle side for charging the battery mounted on the unmanned vehicle, and the ground side charger is provided with a ground side charging terminal. Positive and negative charging terminals are provided. Then, the automatic charging device for the unmanned vehicle automatically charges the battery with the charger in a state where the positive and negative charging terminals on the ground side are connected to the positive and negative charging terminals on the unmanned vehicle side.

In the automatic charging device for an unmanned vehicle disclosed in Patent Document 1, the ground side positive and negative charging terminals are slidably supported by the housing. The ground side positive and negative charging terminals are biased in a direction to protrude from the housing by a compression coil spring, and the tips of the ground side positive and negative charging terminals protrude from the housing. A limit switch is fixed to the housing. When the ground side positive and negative charging terminals move a predetermined amount against the biasing force of the compression coil spring, the limit switch is turned on.

When the ground-side positive and negative charging terminals come into contact with the unmanned vehicle-side positive and negative charging terminals and are further moved, the ground-side positive and negative charging terminals move relatively within the housing, and the limit switch is turned on. The limit switch signal is sent to the charge controller. When the charge controller determines that the ground-side positive and negative charging terminals and the unmanned vehicle-side positive and negative charging terminals are in proper contact after the limit switch is turned on, charging by the charger is started. A limit switch is provided on the ground side, and by checking the contact with the limit switch and stopping the moving operation of the ground side positive and negative charging terminals, charging is possible even if the unmanned vehicle is in a different position as long as it is within the movement stroke.

Japanese Patent Application Publication No. 2010-88215

However, the automatic charging device for an unmanned vehicle disclosed in Patent Document 1 requires a limit switch in order to determine the contact state between the positive and negative charging terminals on the ground side and the positive and negative charging terminals on the unmanned vehicle side after the limit switch is turned on. There is a problem. In other words, a limit switch is required to stop an unmanned vehicle. If a limit switch is required, not only a space for installing the limit switch is required, but also parts for installing the limit switch are required, which increases the manufacturing cost of the charging device.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a charging system that can reliably detect the contact state between a power receiving part and a power feeding part without using a sensor or a switch. On offer.

In order to solve the above problems, the present invention includes an electric traveling body including a power receiving section, and a charging device comprising a power feeding section that can come into contact with the power receiving section, and the electric traveling body has a In a charging system including a motor, a controller that controls the traveling motor, and a power storage device that can be charged via the power receiving section, at least one of the power receiving section and the power feeding section is connected to the power receiving section and the power feeding section. When the parts come into contact with each other, the power receiving part and the power feeding part can be moved forward and backward according to the movement of the electric traveling body, and at least one of the power receiving part and the power feeding part is attached in a direction in which the power receiving part and the power feeding part come into contact with each other. a biasing member that biases the electric vehicle, and the controller causes the electric vehicle to stop relative to the charging device when the torque of the travel motor is equal to or greater than a threshold after the power reception unit and the power supply unit come into contact with each other. The present invention is characterized in that the traveling motor is controlled as follows.

In the present invention, the controller controls the traveling motor so that the electric traveling body stops relative to the charging device when the torque of the traveling motor becomes equal to or greater than a threshold value after the power receiving section and the power feeding section come into contact with each other. After the electric traveling body is stopped, the contact between the power receiving section and the power feeding section is maintained by the urging force of the urging member. That is, by monitoring the torque of the driving motor, the contact state between the power receiving section and the power supply section can be reliably detected, so there is no need to use a sensor or a switch to detect the contact state.

Further, in the above-mentioned charging system, the power feeding unit includes a power feeding side electrode body that is biased by the biasing member and can move forward and backward, and the power receiving unit includes a running body side electrode body that is fixed to the electric running body. It is good also as a structure provided with.
In this case, by allowing the power feeding side electrode body to move forward and backward, there is no need to move the traveling body side electrode body of the electric traveling body forward and backward, and there is no need to secure a space on the electric traveling body for the movement of the traveling body side electrode body.

Furthermore, in the charging system described above, the biasing member may be a coil spring.
In this case, by using a coil spring as the biasing member, the torque of the traveling motor increases continuously until it reaches a threshold value or more, and the controller is able to increase the torque due to reasons other than contact between the power receiving part and the power supply part. It becomes easier to distinguish.

Further, in the above-mentioned charging system, a charging area is set around the charging device, and the controller includes a communication unit that enables communication between the electric traveling object and the charging device, and the controller is configured to When present in the charging area, the charging device may be controlled via the communication unit so as to start charging after the electric vehicle stops.
In this case, the in-vehicle controller can limit the area where charging is possible by setting the charging area, and can control the charging device through communication from the communication unit.

Furthermore, in the charging system described above, the controller may be configured to start charging when the torque exceeds a threshold value in a preset torque fluctuation pattern.
In this case, when the torque becomes equal to or greater than the threshold value in a preset torque fluctuation pattern, charging of the power storage device via the power reception unit and the power supply unit can be started. Furthermore, it is also possible to prevent charging when the battery voltage exceeds a threshold value in a variation pattern other than a preset variation pattern.

According to the present invention, it is possible to provide a charging system that can reliably detect the contact state between a power receiving section and a power feeding section without using a sensor or a switch.

FIG. 1 is a schematic plan view of a charging system according to a first embodiment. FIG. 1 is a schematic side view of a charging system according to a first embodiment. FIG. 1 is a schematic configuration diagram of a charging system according to a first embodiment. FIG. 2 is a flow diagram showing a charging procedure by the charging system according to the first embodiment. FIG. 2 is a graph diagram showing the relationship between the torque of the traveling motor and the distance traveled by the automatic guided vehicle after contact with the power receiving unit. (a) is a side view showing a state immediately after the power receiving part and the power feeding part are in contact with each other, and (b) is a side view showing a state in which the power receiving part pushes the power feeding part. FIG. 3 is a schematic side view of a charging system according to a second embodiment. FIG. 3 is a schematic side view of a charging system according to a third embodiment.

(First embodiment)
Hereinafter, a charging system according to a first embodiment will be described with reference to the drawings. This embodiment will be described by exemplifying a charging system that includes an automatic guided vehicle as an electric vehicle and a charging device that charges the automatic guided vehicle.

As shown in FIG. 1, the charging system 10 includes an automatic guided vehicle 11 as an electric vehicle and a charging device 12. The automatic guided vehicle 11 is an automatic guided vehicle that autonomously travels while avoiding obstacles. As shown in FIG. 2, the upper part of the vehicle body 13 of the automatic guided vehicle 11 is provided with a loading platform 14 on which a load W can be placed. The front portion of the vehicle body 13 is provided with a pair of left and right steering wheels 15 as front wheels, and the rear portion of the vehicle body 13 is provided with a pair of left and right drive wheels 16 as rear wheels. The steering wheel 15 is steered by a steering motor (not shown). A pair of left and right drive wheels 16 are rotated by driving a travel motor 17 .

A battery 18 as a power storage device is mounted on the vehicle body 13. The battery 18 is a rechargeable and dischargeable secondary battery, for example, a lithium ion battery. The battery 18 is connected to various parts that require electric power, such as the steering motor and the traveling motor 17, through power wiring (not shown). Therefore, the power of the battery 18 is supplied to each part of the vehicle body 13 through the power wiring. Furthermore, power generated during regeneration is stored in the battery 18 through power wiring.

In this embodiment, a power receiving section 19 for charging the battery 18 is provided at the front of the vehicle body 13. The power receiving unit 19 includes a positive terminal 21 and a negative terminal 22 as a traveling body side electrode body. The positive electrode terminal 21 and the negative electrode terminal 22 are arranged in a recess 23 formed in the front part of the vehicle body 13. The power receiving unit 19 is fixed to the vehicle body 13 so that the positive terminal 21 and the negative terminal 22 are located above and below each other (see FIG. 2). The positive terminal 21 and the negative terminal 22 are connected to corresponding terminals of the battery 18 via power lines 28 and 29. The power receiving unit 19 includes an on-vehicle communication device 24 for communicating with the charging device 12 by optical communication. Since the positive electrode terminal 21 and the negative electrode terminal 22 are arranged in the recess 23, they are unlikely to interfere with obstacles.

The vehicle body 13 is equipped with an on-vehicle controller 25 as a controller that controls each part of the automatic guided vehicle 11 . As shown in FIG. 3, the in-vehicle controller 25 includes a CPU 26 and a storage section 27 including a RAM, a ROM, and the like. The on-vehicle controller 25 may include dedicated hardware that executes at least some of the various processes, such as an application specific integrated circuit (ASIC). The on-vehicle controller 25 may be configured as a circuit including one or more processors operating according to a computer program, one or more dedicated hardware circuits such as an ASIC, or a combination thereof.

The storage unit 27 stores program codes or instructions configured to cause the CPU 26 to execute processes. The storage unit 27 stores various programs for controlling each part of the automatic guided vehicle 11. The on-vehicle controller 25 can control the direction and speed of the automatic guided vehicle 11 by controlling the steering motor and the traveling motor 17, for example. be.

The storage unit 27 stores an environmental map related to the movement space in which the automatic guided vehicle 11 moves. The environmental map is a map that the automatic guided vehicle 11 creates while moving in the movement space. A technique for simultaneously estimating the self-position of the automatic guided vehicle 11 and constructing an environmental map is called SLAM (Simultaneous Localization and Mapping). Storage 27, or computer readable media, includes anything that can be accessed by a general purpose or special purpose computer. By mounting a laser range finder (LRF: light wave range finder) on the automatic guided vehicle 11, the vehicle-mounted controller 25 creates an environmental map while estimating its own position.

The environmental map includes position information of a charging area E set around the charging device 12. The vehicle-mounted controller 25 sets the driving mode of the automatic guided vehicle 11 to the normal driving mode outside the charging area E, and to the charging driving mode inside the charging area E. In the normal driving mode, charging of the battery 18 by the charging device 12 is disabled, and in the charging driving mode, charging of the charging device 12 is enabled.

The on-vehicle controller 25 of this embodiment performs charging control based on communication with the charging device 12. When the automatic guided vehicle 11 is connected to the charging device 12 in a chargeable state, a charging command is issued to the charging device 12 to charge the battery 18. The charging control procedure will be described later. Furthermore, the on-vehicle controller 25 has a function of monitoring the torque of the running motor 17 while being driven, and calculates the torque based on the current value of the running motor 17.

Next, the charging device 12 will be explained. The charging device 12 of this embodiment is installed on a road surface (floor surface). The charging device 12 includes a device main body 31, a power feeding section 32, a coil spring 33 as a biasing member, and a charging side controller 34.

A power supply section 32 is provided on the side of the box-shaped device main body 31. The power feeding unit 32 includes a power feeding base 35, and a positive terminal 36 and a negative terminal 37 as power feeding side electrode bodies. The power supply base 35 has a space 38 into which the positive electrode terminal 36 is movably inserted and a space 39 into which the negative electrode terminal 37 is movably inserted. The positive electrode terminal 36 is a cylindrical body inserted into the space 38, protrudes from the side of the device main body 31, and is provided so as to be movable forward and backward relative to the power supply base 35. The negative electrode terminal 37 is a cylindrical body inserted into the space 39, protrudes from the side of the device main body 31, and is provided so as to be movable forward and backward relative to the power supply base 35.

The positive electrode terminal 36 and the negative electrode terminal 37 are arranged one above the other (see FIG. 2). The power supply unit 32, which includes a positive terminal 36 and a negative terminal 37, is connected to a charger 40 via power lines 42 and 43, and the charger 40 is connected to an external power source (not shown) (FIG. 3). ). The positive electrode terminal 36 and the negative electrode terminal 37 are biased in a protruding direction by a coil spring 33 as a biasing member. The coil spring 33 is a compression coil spring, and is housed in the spaces 38 and 39, respectively. When the protruding ends of the positive terminal 36 and the negative terminal 37 are pushed in, the ends of the positive terminal 36 and the negative terminal 37 on the space side move in a direction that compresses the coil spring 33. The biasing force of the coil spring 33 follows Hooke's law.

The power feeding unit 32 includes a charging side communication device 41 for communicating with the automatic guided vehicle 11 by optical communication. The on-vehicle communication device 24 and the charging side communication device 41 correspond to a communication unit that enables communication between the automatic guided vehicle 11 and the charging device 12. The charging side controller 34 controls each part of the charging device 12. Specifically, in addition to controlling the power supply unit 32, the charging side communication device 41 is also controlled. The charging side controller 34 issues a command regarding charging by the power supply unit 32.

Next, a procedure for detecting a contact state between the power receiving section 19 of the automatic guided vehicle 11 and the power feeding section 32 of the charging device 12 by the charging system 10 will be described. As shown in FIG. 4, when a charging request is generated for the running automatic guided vehicle 11, the on-vehicle controller 25 first runs toward the charging device 12 (step S101). At this time, the automatic guided vehicle 11 is running in the normal running mode. A charging request is determined based on the remaining capacity of the battery 18. In the normal running mode, when the torque of the running motor 17 exceeds a threshold value, the on-vehicle controller 25 determines that there is an abnormality and makes an emergency stop.

Next, it is determined whether the current position of the automatic guided vehicle 11 is within the charging area E (step S102). When it is determined that the current position of the automatic guided vehicle 11 is within the charging area E, the on-vehicle controller 25 switches the driving mode of the automatic guided vehicle 11 from the normal driving mode to the charging driving mode. Then, the vehicle travels toward the charging device 12 in the charging travel mode (step S103). In the charging driving mode, charging is possible when the torque of the driving motor 17 is equal to or higher than a threshold value. If the on-vehicle controller 25 determines that it is not within the charging area E, the process returns to step S101.

Next, the on-vehicle controller 25 determines whether the torque of the travel motor 17 is equal to or greater than a threshold value T (step S104). The torque of the traveling motor 17 is monitored by an on-vehicle controller 25. When the on-vehicle controller 25 determines that the torque of the travel motor 17 is equal to or greater than the threshold value T, it determines whether the torque increase of the travel motor 17 follows a preset variation pattern (step S105).

When the automatic guided vehicle 11 continues to travel with the power receiving section 19 and the power feeding section 32 in contact with each other, the positive terminal 36 and the negative terminal 37 of the power feeding section 32 are pushed against the spring force (biasing force) of the coil spring 33. It will be done. Therefore, the coil spring 33 is compressed, and the spring force of the coil spring 33 becomes a reaction force to the power receiving unit 19, but the increase in the spring force is continuous and linear, according to Hooke's law. Since the automatic guided vehicle 11 attempts to travel against the spring force, the torque of the travel motor 17 is continuous and linear in response to the increase in the spring force, as shown in FIG. It will increase. A continuous and linearly increasing variation pattern (hereinafter referred to as "set torque variation pattern") of the torque of the driving motor 17 is preset in the on-vehicle controller 25. If the fluctuation in torque increase is in the set torque fluctuation pattern, the on-vehicle controller 25 can recognize that the power receiving section 19 and the power feeding section 32 are in contact with each other. The threshold T may be a torque corresponding to the urging force when the height of the coil spring 33 is between the free height and the close contact height.

When the on-vehicle controller 25 determines that the increase in torque of the travel motor 17 corresponds to the set torque fluctuation pattern, the vehicle controller 25 controls the travel motor 17 to stop the automatic guided vehicle 11 (step S106). Next, the in-vehicle controller 25 performs optical communication between the in-vehicle communication device 24 and the charging side communication device 41 (step S107). Then, the on-vehicle controller 25 determines whether charging is possible based on the communication result (step S108). Specifically, the on-vehicle controller 25 issues a command to the charging device 12 through communication, causes a current to flow from the power feeding section 32 to the power receiving section 19, and detects the voltage at the power receiving section 19, thereby allowing charging. Discern. When the in-vehicle controller 25 determines that the power receiving unit 19 and the power feeding unit 32 can be charged, it sends a command to the charging side controller 34 of the charging device 12 to start charging through communication (step S109). The charging side controller 34 starts charging the battery 18 in response to a command from the on-vehicle controller 25 (step S110). The series of flows ends with the start of charging.

If it is determined in step S105 that the torque increase of the driving motor 17 is not in the set torque fluctuation pattern, it is assumed that an abnormality has occurred in which the power supply section 32 is in contact with an obstacle other than the power reception section 19, and the flow is terminated ( Step S111). Further, if it is determined in step S107 that the connection between the power receiving unit 19 and the power feeding unit 32 is not normal, the flow is terminated as the connection is abnormal (step S111).

Next, charging of the battery 18 of the automatic guided vehicle 11 by the charging system 10 of this embodiment will be described. The automatic guided vehicle 11 travels in a normal travel mode to transport the load W. When the automatic guided vehicle 11 is running, the on-vehicle controller 25 constantly monitors the torque of the running motor 17. When the remaining capacity of the battery 18 decreases to a predetermined remaining capacity due to repeated driving of the automatic guided vehicle 11, the on-vehicle controller 25 issues a command to request charging. When a charge request command is issued, the on-vehicle controller 25 controls each part including the travel motor 17 so that the automatic guided vehicle 11 travels toward the charging device 12.

The automatic guided vehicle 11 travels toward the charging device 12, but when the automatic guided vehicle 11 exists outside the charging area E of the charging device 12, it continues to travel in the normal traveling mode. At this time, if the automatic guided vehicle 11 interferes with an obstacle and tries to continue traveling for some reason, the torque of the traveling motor 17 may exceed the threshold T, but the on-vehicle controller 25 recognizes this as an abnormality. The automatic guided vehicle 11 is stopped. On the other hand, when the automatic guided vehicle 11 exists within the charging area E of the charging device 12, the on-vehicle controller 25 switches the driving mode from the normal driving mode to the charging driving mode, and the automatic guided vehicle 11 runs in the charging driving mode. , aiming at the charging device 12.

As shown in FIG. 6A, as the automatic guided vehicle 11 travels, the power receiving section 19 and the power feeding section 32 come into contact with each other. Furthermore, as the automatic guided vehicle 11 continues to travel, the positive terminal 36 and the negative terminal 37 of the power feeding section 32 are pushed in against the biasing force of the coil spring 33, for example, as shown in FIG. 6(b). The biasing force of the coil spring 33 increases according to the amount of compression of the coil spring 33 based on Hooke's law. The positive terminal 21 and the negative terminal 22 in the power receiving section 19 receive the biasing force of the coil spring 33 as a reaction force. Therefore, when the automatic guided vehicle 11 moves in the direction of pushing the positive terminal 36 and the negative terminal 37 of the power feeding section 32 after the power receiving section 19 comes into contact with the power feeding section 32, the torque of the driving motor 17 of the automatic guided vehicle 11 increases. Similarly to the increase in the biasing force of the coil spring 33, the biasing force of the coil spring 33 also increases.

The on-vehicle controller 25 is in the charge driving mode, and the torque of the driving motor 17 is equal to or greater than the threshold value T. Then, when the torque fluctuation of the traveling motor 17 is in the set torque fluctuation pattern, the in-vehicle controller 25 determines that the connection between the power receiving section 19 and the power feeding section 32 is normal and that the automatic guided vehicle 11 can be stopped. issue a command to stop. When the automatic guided vehicle 11 is stopped, a biasing force corresponding to the torque of the coil spring 33 that is equal to or greater than the threshold value T always acts on the positive terminal 21 and the negative terminal 22 of the power receiving unit 19 . Therefore, even if the automatic guided vehicle 11 stops, the contact between the positive electrode terminal 21 and the positive electrode terminal 36 and the contact between the negative electrode terminal 22 and the negative electrode terminal 37 are maintained.

After the automatic guided vehicle 11 is stopped, the on-vehicle controller 25 performs optical communication with the charging side communication device 41 via the on-vehicle communication device 24, and if charging is possible, issues a charging command to the charging device 12. The charging device 12 starts charging the battery 18 in response to a command from the on-vehicle controller 25. When charging of the battery 18 is completed, the vehicle-mounted controller 25 controls the driving motor 17 to move the automatic guided vehicle 11 away from the charging device 12. When the automatic guided vehicle 11 separates from the charging device 12 and goes outside the charging area E, the automatic guided vehicle 11 switches the driving mode from the charging driving mode to the normal driving mode.

The charging system 10 of this embodiment has the following effects.
(1) The on-vehicle controller 25 controls the driving so that the automatic guided vehicle 11 stops relative to the charging device 12 when the torque of the driving motor 17 becomes equal to or higher than a threshold value T after the power receiving unit 19 and the power feeding unit 32 come into contact with each other. Controls the motor 17. After the automatic guided vehicle 11 is stopped, the contact between the power receiving section 19 and the power feeding section 32 is maintained by the biasing force of the coil spring 33. In other words, by monitoring the torque of the traveling motor 17, the contact state between the power receiving section 19 and the power supply section 32 can be reliably detected, so it is not necessary to use a sensor or a switch to detect the contact state. There is no. As a result, the manufacturing cost of the charging system 10 can be suppressed.

(2) The power feeding unit 32 is biased by a coil spring 33 and includes a positive terminal 36 and a negative terminal 37 that can move forward and backward, and the power receiving unit 19 has a positive terminal 21 and a negative terminal 37 fixed to the vehicle body 13 of the automatic guided vehicle 11. A negative electrode terminal 22 is provided. Therefore, by making the positive terminal 36 and the negative terminal 37 movable, it is not necessary to move the positive terminal 21 and the negative terminal 22 of the automatic guided vehicle 11 back and forth, and the positive terminal 21 and the negative terminal 22 of the automatic guided vehicle 11 can be moved back and forth. There is no need to secure space for advancing and retreating.

(3) By using the coil spring 33 as the biasing member, the torque of the driving motor 17 increases continuously until it reaches the threshold value or more, and the in-vehicle controller 25 can connect the power receiving section 19 and the power feeding section 32. This makes it easier to distinguish that the torque increase is caused by something other than contact. Moreover, when the automatic guided vehicle 11 stops, the ground pressure required for charging can be ensured between the power receiving section 19 and the power feeding section 32 by the biasing force of the coil spring 33.

(4) A charging area E is set around the charging device 12. Charging system 10 includes a communication unit that enables communication between automatic guided vehicle 11 and charging device 12 . When the automatic guided vehicle 11 is present in the charging area E, the on-vehicle controller 25 controls the charging device 12 via the on-vehicle communication device 24 and the charging side communication device 41 so as to start charging after the automatic guided vehicle 11 has stopped. do. The on-vehicle controller 25 can limit the area where charging is possible by setting the charging area E, and can control the charging device 12 through communication from the communication section.

(5) The on-vehicle controller 25 can start charging when the torque of the driving motor 17 exceeds the threshold value T in the set torque fluctuation pattern. It is also possible to not perform charging when the torque exceeds the threshold T in a pattern other than the set torque fluctuation pattern. An example where the torque exceeds the threshold T outside of the set torque fluctuation pattern may be due to interference between the automatic guided vehicle 11 and an obstacle where the torque suddenly increases, and the on-vehicle controller 25 immediately stops the automatic guided vehicle 11 as an abnormality has occurred. can do.

(Second embodiment)
Next, a charging system according to a second embodiment will be described. This embodiment differs from the first embodiment in that the positive terminal and negative terminal included in the power receiving unit can move forward and backward according to the movement of the automatic guided vehicle, and the positive terminal and negative terminal included in the power feeding unit are fixed. It differs from In this embodiment, the first embodiment is used for the same configuration as the first embodiment, and common symbols are used.

As shown in FIG. 7, the charging system 50 includes an automatic guided vehicle 51 as an electric vehicle and a charging device 52. A power receiving section 53 for charging the battery 18 is provided at the front of the vehicle body 13. The power receiving unit 53 includes a positive terminal 54 and a negative terminal 55 as a traveling body side electrode body. The power receiving section 53 has a space 56 into which the positive electrode terminal 54 is inserted so as to be movable forward and backward, and a space 57 into which the negative electrode terminal 55 is inserted so as to be movable forward and backward.

The positive electrode terminal 54 is a cylindrical body inserted into the space 56, protrudes from the front part of the vehicle body 13, and is provided so as to be movable relative to the vehicle body 13. The negative electrode terminal 55 is a cylindrical body inserted into the space 57, protrudes from the front part of the vehicle body 13, and is provided so as to be movable forward and backward with respect to the vehicle body 13. The positive terminal 54 and the negative terminal 55 are biased in the protruding direction by a coil spring 33 as a biasing member. The coil spring 33 is a compression coil spring, and is housed in the spaces 56 and 57, respectively.

The power feeding unit 58 of the charging device 52 includes a power feeding base 35, and a positive terminal 59 and a negative terminal 61 as power feeding side electrode bodies. The positive electrode terminal 59 and the negative electrode terminal 61 are arranged in a recess 62 formed on the side of the device main body 31. The positive terminal 59 and the negative terminal 61 are fixed to the power supply base 35.

This embodiment provides effects equivalent to effects (1), (3) to (5) of the first embodiment. The power receiving section 53 is biased by the coil spring 33 and includes a positive terminal 54 and a negative terminal 55 that can move forward and backward, and the power feeding section 58 has a positive terminal 59 and a negative terminal 61 fixed to the power feeding base 35. We are prepared. Therefore, by making the positive terminal 54 and the negative terminal 55 movable, it is not necessary to move the positive terminal 59 and the negative terminal 61 of the charging device 52 back and forth, and the charging device 52 can move the positive terminal 59 and the negative terminal 61 back and forth. Therefore, there is no need to secure space.

(Third embodiment)
Next, a charging system according to a third embodiment will be described. This embodiment differs from the first embodiment in that not only the power feeding section but also the positive terminal and the negative terminal provided in the power receiving section can move forward and backward in accordance with the movement of the automatic guided vehicle. In this embodiment, the first embodiment is used for the same configuration as the first embodiment, and common symbols are used.

As shown in FIG. 8, the charging system 70 includes an automatic guided vehicle 71 as an electric vehicle and a charging device 12. A power receiving section 73 for charging the battery 18 is provided at the front of the vehicle body 13. The power receiving section 73 includes a positive terminal 74 and a negative terminal 75 as a traveling body side electrode body. The power receiving section 73 has a space 76 into which the positive electrode terminal 74 is inserted so as to be movable back and forth, and a space 77 into which the negative electrode terminal 75 is inserted so as to be movable back and forth.

Although the positive electrode terminal 74 is inserted into the space 76, it does not protrude from the front part of the vehicle body 13 and is provided so as to be movable forward and backward relative to the vehicle body 13. Although the negative electrode terminal 75 is inserted into the space 77, it does not protrude from the front of the vehicle body 13 and is provided so as to be movable forward and backward relative to the vehicle body 13. The positive electrode terminal 74 and the negative electrode terminal 75 are biased in a protruding direction by a coil spring 33 as a biasing member. The coil spring 33 is a compression coil spring, and is housed in the spaces 76 and 77, respectively.

This embodiment provides effects equivalent to effects (1), (3) to (5) of the first embodiment. The power receiving unit 73 is biased by the coil spring 33 and includes a positive terminal 74 and a negative terminal 75 that can move forward and backward, and the power feeding unit 32 includes a positive terminal 36 and a negative terminal 37 that can move forward and backward in the power feeding base 35. ing. Therefore, by moving the positive terminals 36, 74 and the negative terminals 37, 75 back and forth, the state of contact between the power receiving section 73 and the power feeding section 32 can be reliably detected.

The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the invention. For example, the following modifications may be made.

In the above embodiment, a compression coil spring is used as an example of the biasing member, but the present invention is not limited thereto. The biasing member may be, for example, a tension coil spring. Further, the biasing member is not limited to a coil spring, but may be an elastic member made of a rubber-based material whose biasing force increases continuously.
○ In the above embodiment, the case where the charging area is set around the charging device has been described, but the present invention is not limited to this. For example, the charging device may be controlled via the communication unit so as to start charging after the electric vehicle has stopped without setting a charging area.
In the above embodiment, charging is started when the torque of the driving motor exceeds a threshold value in a preset torque fluctuation pattern, but the present invention is not limited to this. For example, charging may be started even when the torque of the driving motor simply exceeds a threshold value.
In the above embodiment, the torque increase in the set torque variation pattern is continuous and linear, but the present invention is not limited to this. Although the torque increase in the set torque variation pattern does not have to be linear, it is preferable that the torque increase be continuous.
○ In the above embodiment, the controller determines whether the torque of the travel motor is equal to or higher than the threshold value, and when it is determined that the torque of the travel motor is equal to or higher than the threshold value, the controller increases the torque of the travel motor by setting the increase in the torque of the travel motor in advance. However, the present invention is not limited to this. For example, the controller determines whether or not the torque increase of the travel motor is in a preset variation pattern, and when determining that the torque increase is in the set torque fluctuation pattern, the controller determines whether the torque of the travel motor is equal to or higher than a threshold value. It may also be determined whether or not there is one.
〇 In the above embodiment, the controller issues a stop command when it determines that the torque of the travel motor is equal to or higher than the threshold value, and furthermore, when the torque increase of the travel motor is in a preset set torque fluctuation pattern. However, it is not limited to this. For example, if the controller determines that the torque of the travel motor is equal to or higher than a threshold value, the controller may issue a stop command, and the torque increase of the travel motor after the electric vehicle stops is a preset torque fluctuation pattern. It may be determined whether or not.
In the embodiments described above, it is assumed that the automatic guided vehicle as an electric vehicle travels autonomously using SLAM, but the present invention is not limited to this. For example, it may be an electric vehicle that travels while being guided by a magnetic tape or the like installed on the road surface.
In the above embodiment, an automatic guided vehicle including a steered wheel and a driving wheel was described as an example of an electric vehicle, but the present invention is not limited thereto. For example, the electric vehicle may be an electric vehicle equipped with omnidirectional wheels such as omni wheels.
In the above embodiment, an automatic guided vehicle has been described as an example of an electric vehicle, but the present invention is not limited thereto. The electric vehicle may be, for example, an unmanned forklift or an unmanned towing tractor, or an autonomously traveling electric vacuum cleaner or a security robot. Further, the present invention can be applied to an electric traveling body that can be operated by a man on board an operator, or an electric traveling body that can be operated remotely. In an electric vehicle that can be operated manually or remotely, when the torque of the driving motor exceeds a threshold value, the driving motor is stopped, thereby preventing generation of excessive load on the driving motor due to operation.

10, 50, 70 Charging system 11, 51, 71 Automatic guided vehicle 12, 52 Charging device 13 Vehicle body 15 Steering wheel 16 Drive wheel 17 Traveling motor 18 Battery 19, 53, 73 Power receiving unit 21, 54, 74 Positive terminal (power receiving Department)
22, 55, 75 Negative terminal (power receiving part)
24 On-vehicle communication device 25 On-vehicle controller 32, 58 Power supply part 33 Coil spring 34 Charging side controller 36, 59 Positive terminal (power supply part)
37, 61 Negative terminal (power supply part)
41 Charging side communication device E Charging area W Load

Claims (5)

An electric traveling body including a power receiving unit;
a charging device including a power feeding part that can come into contact with the power receiving part,
The electric traveling body is
A running motor,
a controller that controls the traveling motor;
A charging system comprising: a power storage device that can be charged via the power receiving unit;
At least one of the power receiving unit and the power feeding unit,
When the power receiving section and the power feeding section are in contact with each other, the power receiving section and the power feeding section can move forward and backward according to the movement of the electric traveling body, and the power receiving section and the power feeding section can connect at least one of the power receiving section and the power feeding section. A biasing member that biases in a direction in which they come into contact with each other,
The controller controls the traveling motor so that the electric traveling body stops relative to the charging device when the torque of the traveling motor is equal to or higher than a threshold after the power receiving unit and the power feeding unit come into contact with each other. A charging system characterized by: The power feeding unit includes a power feeding side electrode body that is biased by the biasing member and can move forward and backward;
The charging system according to claim 1, wherein the power receiving unit includes a traveling body side electrode body fixed to the electric traveling body. The charging system according to claim 1 or 2, wherein the biasing member is a coil spring. A charging area is set around the charging device,
a communication unit that enables communication between the electric vehicle and the charging device;
2. The controller controls the charging device via the communication unit to start charging after the electric vehicle stops when the electric vehicle is present in the charging area. Or the charging system described in 2. 5. The charging system according to claim 4, wherein the controller starts charging when the torque exceeds a threshold value in a preset torque fluctuation pattern.

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