ASPHALT FINISHER AND POWER SUPPLY SYSTEM FOR ASPHALT FINISHER

Abstract

An asphalt finisher is provided that includes a tractor; a hopper mounted on a front side of the tractor; a conveyor that conveys a paving material in the hopper to a rear side of the tractor; a screw that spreads the paving material, which is scattered on a road surface by the conveyor, in a vehicle width direction; a screed device that lays and levels the paving material, which is spread by the screw, at a rear side of the screw; an actuator that drives at least one selected from the group consisting of the tractor, the conveyor, the screw, and the screed device using electric power; a power storage unit; and a power supply unit that is connectable to an external device and can receive electric power supplied from the external device.

Claims

1. An asphalt finisher, comprising: a tractor; a hopper mounted on a front side of the tractor; a conveyor that conveys a paving material in the hopper to a rear side of the tractor; a screw that spreads the paving material, which is scattered on a road surface by the conveyor, in a vehicle width direction; a screed device that lays and levels the paving material, which is spread by the screw, at a rear side of the screw; an actuator that drives at least one component selected from the group consisting of the tractor, the conveyor, the screw, and the screed device using electric power; a power storage unit; and a power supply unit that is connectable to an external device and can receive electric power supplied from the external device.

2. A power supply system for an asphalt finisher, the power supply system comprising: the asphalt finisher according to claim 1.

3. The power supply system for the asphalt finisher, according to claim 2, wherein the power supply unit is configured to supply electric power from a power source of the external device to the power storage unit, and is configured to supply electric power from the power source of the external device to the actuator.

4. The power supply system for the asphalt finisher, according to claim 2, wherein the power supply unit is configured to supply both electric power from the power source of the external device and electric power from the power storage unit to the actuator.

5. The power supply system for the asphalt finisher, according to claim 2, further comprising: a dump truck as the external device, where the dump truck includes a power source and a truck-side power supply unit, wherein the power supply unit is electrically connectable to the truck-side power supply unit, and is configured to supply electric power from the power source of the dump truck to the power storage unit, thereby charging the power storage unit.

6. The power supply system for the asphalt finisher, according to claim 5, wherein the power supply unit is configured to receive electric power supplied from the dump truck, when the screed device spreads the paving material while the asphalt finisher is moved in a predetermined travel direction by the tractor, and wherein the dump truck is configured to perform speed control based on speed of the asphalt finisher.

7. The power supply system for the asphalt finisher, according to claim 5, wherein the truck-side power supply unit is disposed at a rear side of the dump truck, and wherein the power supply unit is arranged at a front side of the hopper, and is arranged at a position at which the power supply unit can receive electric power from the truck-side power supply unit, when the dump truck is docked on a front side of the asphalt finisher.

8. The power supply system for the asphalt finisher, according to claim 5, further comprising: a detection unit that detects whether it is possible to perform power supply between the power supply unit and the truck-side power supply unit, wherein, when the detection unit detects that it is possible to perform power supply between the power supply unit and the truck-side power supply unit, the power supply unit is configured to receive electric power supplied from the power source of the dump truck.

9. The power supply system for the asphalt finisher, according to claim 8, wherein the detection unit is an imaging device capable of detecting whether the power supply unit and the truck-side power supply unit are in connectable positions.

10. The power supply system for the asphalt finisher, according to claim 5, further comprising: a detection unit that detects a charge rate of the power storage unit, wherein the power supply system is configured to perform control of power supply from the truck-side power supply unit via the power supply unit based on the charge rate of the power storage unit detected by the detection unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 is a view illustrating a configuration example of a construction management system according to an embodiment;

[0007] FIG. 2 is an explanatory diagram illustrating a scene of the embodiment where loading of a paving material from a plant to a dump truck and charging of a battery are performed;

[0008] FIG. 3 is a configuration diagram illustrating a hydraulic system and a power supply system mounted on the asphalt finisher according to the embodiment;

[0009] FIG. 4A is a left side view illustrating a scene of the embodiment where the dump truck is moved backward to approach the asphalt finisher;

[0010] FIG. 4B is a top view illustrating a scene of the embodiment where the dump truck is moved backward to approach the asphalt finisher;

[0011] FIG. 5A is a left side view illustrating a state before the dump truck is docked on the asphalt finisher 100 according to Modification Example 3; and

[0012] FIG. 5B is a top view illustrating the state before the dump truck is docked on the asphalt finisher 100 according to Modification Example 3.

DETAILED DESCRIPTION

[0013] Asphalt finishers of the related art generally include internal combustion engines, such as diesel engines, and electrification of asphalt finishers has not been considered.

[0014] In view of the above, an asphalt finisher including an electric actuator instead of an internal combustion engine, such as a diesel engine, is proposed.

[0015] According to one aspect of the present disclosure, an asphalt finisher is driven by electric power supplied to a power storage unit, thus an environmentally friendly asphalt finisher can be provided.

[0016] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding components are denoted by the same or corresponding reference numerals, and the description thereof may be omitted.

[0017] First, a configuration of a construction management system SYS according to one embodiment of the present disclosure will be described with reference to FIG. 1. FIG. 1 is a view illustrating a configuration example of construction management system SYS.

[0018] The construction management system SYS mainly includes an asphalt finisher 100, a dump truck 200, and a plant 300.

[0019] The asphalt finisher 100 is a machine used for paving roads and the like. Specifically, the asphalt finisher 100 mainly includes a tractor 1, a hopper 2, and a screed 3.

[0020] The asphalt finisher 100 according to the present embodiment is an asphalt finisher configured as an electric vehicle (EV), and includes an electric motor 7 for pumps (see FIG. 3) serving as a prime mover, a power supply connector (one example of a power supply unit) 70, and a battery 71 serving as a power storage unit. In the asphalt finisher 100 of the present embodiment, the battery 71 is provided within a tractor 1. Electric power supplied from the battery 71 is supplied to the electric motor 7 for pumps. Thus, the electric motor 7 for pumps transmits power to the tractor 1 and the screed 3. The concrete configuration of the asphalt finisher 100 will be described later.

[0021] As the battery 71 serving as the power storage unit, for example, a lithium-ion secondary battery is used, but any rechargeable secondary battery can be used.

[0022] The asphalt finisher 100 is configured such that the battery 71 can be charged by electric power supplied from the dump truck 200. For this purpose, the asphalt finisher 100 includes the power supply connector (one example of the power supply unit) 70 for connecting to the dump truck 200.

[0023] The tractor 1 is a mechanism for causing the asphalt finisher 100 to travel. In the example illustrated in FIG. 1, the tractor 1 is configured to move the asphalt finisher 100 by rotating rear wheels 5 using a rear-wheel driving motor and rotating front wheels 6 using a front-wheel driving motor. The rear-wheel driving motor and the front-wheel driving motor are hydraulic motors that rotate by receiving a hydraulic fluid supplied by a hydraulic pump. The tractor 1 may have a crawler instead of the wheels.

[0024] The hopper 2 is a mechanism for receiving a paving material. The paving material is, for example, an asphalt mixture (asphalt composite). In the example illustrated in FIG. 1, the hopper 2 is mounted on the front side of the tractor 1, and is configured to open and close in a vehicle width direction by a hopper cylinder 2c. The asphalt finisher 100 generally receives the paving material discharged from a bed 201 of the dump truck 200 with the hopper 2 being fully open. Simultaneously with receipt of the paving material discharged from the bed 201 of the dump truck 200, the asphalt finisher 100 can continue traveling, while pushing the dump truck 200 forward with a push roller 2b. As the paving material in the hopper 2 decreases, an operator of the asphalt finisher 100 closes the hopper 2 so that the paving material near inner walls of the hopper 2 can be gathered into the center of the hopper 2. This allows a conveyor provided at the center of the bottom surface of the hopper 2 to convey the paving material to the rear side of the tractor 1. The paving material conveyed to the rear side of the tractor 1 is scattered on a road surface, which is located behind the tractor 1 and in front of the screed 3, by the screw, followed by spreading the scattered paving material in the vehicle width direction.

[0025] Moreover, the asphalt finisher 100 receives supply of electric power via the power supply connector 70 connected to a truck-side power supply connector 203 provided on the dump truck 200, when receiving the paving material discharged from the bed 201 of the dump truck 200.

[0026] A space recognition device M1 for monitoring the state of the front of the tractor 1 may be attached to the tractor 1. The space recognition device M1 includes, for example, a monocular camera, a stereo camera, a millimeter wave radar, an ultrasonic sensor, a laser radar, a LIDAR, or the like. In the example illustrated in FIG. 1, the space recognition device M1 includes a monocular camera that captures an image of the state of the front of the tractor 1. A controller 30 (see FIG. 3) of the asphalt finisher 100 may determine, for example, whether the dump truck 200 is approaching the asphalt finisher 100, or whether the dump truck 200 is in contact with the asphalt finisher 100 based on an image captured by the monocular camera serving as the space recognition device M1. Then, the controller 30 may notify the determination result to the operator.

[0027] The screed 3 is a mechanism for laying and leveling the paving material. In the example illustrated in FIG. 1, the screed 3 mainly includes a main screed and a telescopic screed. The telescopic screed includes a left telescopic screed and right telescopic screed. The main screed, the left telescopic screed, and the right telescopic screed are arranged to be shifted from one another in a front-back direction. Specifically, the left telescopic screed is arranged behind the main screed, and the right telescopic screed is arranged behind the left telescopic screed. The screed 3 is a floating screed towed by the tractor 1, and is linked with the tractor 1 via leveling arms 3a. The screed 3 moves up and down together with the leveling arms 3a by extension and contraction of screed-lifting cylinders 3b.

[0028] The dump truck 200 is one example of a transport vehicle that transports a paving material to be supplied into the hopper 2 of the asphalt finisher 100. In the example illustrated in FIG. 1, the dump truck 200 is a dump truck, which includes a movable bumper and is dedicated to transport the paving material. The dump truck 200 includes a cabin 202 and a bed 201.

[0029] The dump truck 200 of the present embodiment is a dump truck configured as an electric vehicle (EV), and includes a battery (one example of a power source unit) 204 and a truck-side power supply connector (truck-side power supply unit) 203.

[0030] The dump truck 200 includes the battery 204 serving as the power storage unit, which is embedded in a center portion of a chassis of the vehicle. As the battery 204, for example, a lithium-ion secondary battery is used, but any rechargeable secondary battery can be used.

[0031] The truck-side power supply connector (truck-side power supply unit) 203 is provided for connecting to the power supply connector 70 of the asphalt finisher 100. For example, the truck-side power supply connector (truck-side power supply unit) 203 is provided at a position adjacent to the rear end of the dump truck 200. Thus, the truck-side power supply connector 203 is connected to the power supply connector 70 of the asphalt finisher 100, when the dump truck 200 is docked on the asphalt finisher 100 to discharge the paving material from the bed 201 to the hopper 2. Therefore, the dump truck 200 can supply electric power stored in the battery 204 (one example of a power source that can supply electric power) to the asphalt finisher 100.

[0032] The plant 300 is one example of a production facility for the paving material. In the example illustrated in FIG. 1, the plant 300 mainly includes a mixer 80, a trolley 81, hot silos 82, and the like.

[0033] The mixer 80 is a device for homogeneously mixing aggregates, filler (stone powder), asphalt, and the like. The trolley 81 is a device for transporting the mixture discharged from the mixer 80 to the hot silos 82. The hot silos 82 are devices for maintaining the temperature of the mixture produced by the mixer 80 and storing the mixture. In addition, a controller C3, a space recognition device M3, and a communication device T3 are installed in the plant 300.

[0034] The controller C3 is a control device installed in the plant 300. In the example illustrated in FIG. 1, the controller C3 is a computer including a CPU, a volatile storage device, and a non-volatile storage device, and is installed in a building built on the site of the plant 300. The controller C3 is configured to control the space recognition device M3 and the communication device T3. Functions of the controller C3 can be implemented, for example, by causing the CPU to execute one or more programs stored in the non-volatile storage device. The functions implemented by the controller C3 include, for example, functions of controlling operations of the mixer 80, the trolley 81, the hot silos 82, and the like.

[0035] Further, the controller C3 has functions of controlling supply of electric power using a ground-side power transmission coil 83 and a ground-side power transmission device 84. The ground-side power transmission coil 83 and the ground-side power transmission device 84 will be described later.

[0036] Moreover, the functions implemented by the controller C3 include functions of recognizing the dump truck 200 based on output of the space recognition device M3.

[0037] The space recognition device M3 is configured to monitor a state of the dump truck 200 to which the paving material is loaded in the plant 300. The space recognition device M3 includes, for example, a monocular camera, a stereo camera, a millimeter wave radar, an ultrasonic sensor, a laser radar, a LIDAR, or the like. When the millimeter wave radar, ultrasonic sensor, laser radar, or the like is used as the space recognition device M3, the space recognition device M3 may be configured to transmit a large number of signals (e.g., laser light, etc.) to an object and receive the reflected signals. The space recognition device M3 may be configured to detect a distance between the space recognition device M3 and the object and the direction of the object viewed from the space recognition device M3 based on the reflected signals. In the case where the space recognition device M3 is configured to receive reflected signals transmitted by the LIDAR or the like, the space recognition device M3 may identify the dump truck 200 by recognizing characters displayed on a license plate of the dump truck 200 based on the surface profile of the license plate. As described above, the controller C3 can determine a position, shape, and type of the dump truck 200 using the space recognition device M3. Moreover, the space recognition device M3 may include a combination of two or more devices, such as a combination of a monocular camera and a LIDAR. In the example illustrated in FIG. 1, the space recognition device M3 is a monocular camera that captures an image of a state of the dump truck 200 which is stopped below the mixer 80. In this case, the controller C3 can recognize, for example, a vehicle registration number of the dump truck 200 displayed on the license plate of the dump truck 200 based on an image captured by the monocular camera serving as the space recognition device M3.

[0038] The communication device T3 is configured to control communication between the plant 300 and an external device. In the example illustrated in FIG. 1, the communication device T3 is configured to control wireless communication between the plant 300 and a battery controller (not illustrated) mounted on the dump truck 200.

[0039] FIG. 2 is an explanatory view illustrating a scene according to the present embodiment, where loading of the paving material from the plant 300 to the dump truck 200 and charging of the battery 204 are performed. FIG. 2 illustrates a scene in which a dump truck 200A that is an example of the dump truck 200 is stopped below the mixer 80, and a dump truck 200B that is another example of the dump truck 200 is stopped below the hot silos 82.

[0040] In the present embodiment, the controller C3 determines whether the dump truck 200A is stopped at a predetermined position below the mixer 80 based on output of the space recognition device M3.

[0041] The predetermined position below the mixer is a position at which the paving material can be loaded and the battery 204 of the dump truck 200 can be charged.

[0042] In the case where the controller C3 determines that the dump truck 200A is stopped, the controller C3 acquires an identification number of the dump truck 200A. In the present embodiment, the identification number of the dump truck 200A is a vehicle registration number displayed on a front license plate 210a of the dump truck 200A.

[0043] Specifically, the controller C3 can recognize the vehicle registration number of the dump truck 200A as the identification number by carrying out image recognition processing on the image of the front license plate 210a captured by the monocular camera serving as the space recognition device M3. The controller C3 may recognize the vehicle registration number of the dump truck 200A as the identification number by carrying out image recognition processing on an image of a rear license plate 210b captured by the monocular camera.

[0044] Thereafter, the controller C3 cross-checks the acquired identification number against the identification number prestored in the non-volatile storage device. By this cross-checking, the controller C3 can determine whether the dump truck 200 is a registered dump truck 200 so that, for example, loading of the paving material to an unregistered dump truck 200 can be avoided. Moreover, the controller C3 can prevent the paving material, which will be loaded to a certain dump truck 200, from being loaded to another dump truck 200. Alternatively, the controller C3 can minimize any excess or shortage caused between a weight of the paving material to be loaded to the dump truck 200 and a weight of the paving material actually loaded to the dump truck 200.

[0045] In the case where the controller C3 detects that a predetermined weight of the paving material is discharged from the mixer 80 based on the information from the mixer 80, the controller C3 determines that loading of the paving material to the bed 201 of the dump truck 200A has been completed.

[0046] In the present embodiment, the plant 300 is a batch-type plant, and is configured, for example, to produce 1 ton of the paving material in one batch process. A weight of the paving material to be loaded to the bed 201 of the dump truck 200A is set in advance in association with the identification number of the dump truck 200A. In the case where it is set to load 9 tons of the paving material to the dump truck 200, for example, the controller C3 can therefore determine that loading of the paving material has been completed when nine batch processes are completed based on the information from the mixer 80.

[0047] However, the controller C3 can also determine whether loading of the paving material has been completed based on information other than the information from the mixer 80. For example, the controller C3 may recognize fall of the paving material from the mixer 80 to the bed 201 of the dump truck 200A, namely, recognize that a batch process is completed, by carrying out image recognition processing on an image captured by the monocular camera serving as the space recognition device M3. When the controller C3 detects that a predetermined number of batch processes is completed, the controller C3 may determine that loading of the paving material has been completed.

[0048] Alternatively, the controller C3 may determine whether loading of the paving material is completed based on output of a weight measuring device, such as a truck scale or the like. In this case, the controller C3 may calculate a weight of the paving material loaded to the bed 201 of the dump truck 200 based on output of the weight measuring device.

[0049] Simultaneously with the above loading of the paving material to the bed 201 of the dump truck 200, charging of the battery 204 of the dump truck 200 is performed.

[0050] In the plant 300, a ground-side power transmission coil 83 and a ground-side power transmission device 84 are installed to charge the battery 204.

[0051] The ground-side power transmission device 84 is a power transmission device for charging the battery 204 of the dump truck 200. In the present embodiment, the example where the dump truck 200 is charged by wireless charging is described, but it is merely an example of a charging method for the battery 204 of the dump truck 200. For the charging, another charging method, such as a charging method using a charge gun for electric vehicles, may be used.

[0052] The ground-side power transmission device 84 and the ground-side power transmission coil 83 are connected with each other via an electric power line. A vehicle-side power receiving coil 205 is mounted on the dump truck 200. When the dump truck 200 (200A) is parked in a position at which the vehicle-side power receiving coil 205 vertically overlaps the ground-side power transmission coil 83, the ground-side power transmission device 84 allows an electric current to flow through the ground-side power transmission coil 83 to generate the magnetic flux in the vertical direction relative to the ground surface so that voltage is generated in the vehicle-side power receiving coil 205. Thus, electric power is supplied from the vehicle-side power receiving coil 205 to the battery 204 in the dump truck 200.

[0053] The communication device T3 communicates with the battery controller of the dump truck 200 to acquire SOC of the battery 204. When SOC of the battery 204 acquired by the communication device T3 is detected to be equal to or higher than a set value, the controller C3 determines that charging of the battery 204 of the dump truck 200A has been completed.

[0054] When loading of the paving material and charging of the battery 204 are completed, the dump truck 200 starts moving to supply the paving material to the asphalt finisher 100.

[0055] Next, a hydraulic system and a power supply system mounted on the asphalt finisher 100 will be described with reference to FIG. 3. FIG. 3 is a configuration diagram illustrating the hydraulic system and the power supply system mounted on the asphalt finisher 100.

[0056] The controller 30 controls the entire configuration of the asphalt finisher 100.

[0057] The hydraulic system mainly includes a hydraulic source 14, a rear wheel drive unit F1, and a conveyor-screw drive unit F2.

[0058] The hydraulic source 14 is a functional component that supplies a hydraulic fluid for operating various hydraulic drive units including the rear wheel drive unit F1 and the conveyor-screw drive unit F2. In the present example, the hydraulic source 14 mainly includes an electric motor 7 for pumps, a rear-wheel driving pump 14R, a charge pump 14C, and a conveyor-screw pump 14S.

[0059] The electric motor 7 for pumps (one example of an electric actuator that is a kind of prime mover) is a driving source for driving the rear-wheel driving pump 14R, the charge pump 14C, and the conveyor-screw pump 14S with electric power supplied from the battery 71. Specifically, the electric motor 7 for pumps (an example of an actuator) supplies power to the rear-wheel driving pump 14R, the charge pump 14C, and the conveyor-screw pump 14S to drive the tractor 1, the conveyor, the screw, and the screed 3. In the present embodiment, an example where the electric motor 7 for pumps (an example of an actuator) drives all of the tractor 1, the conveyor, the screw, and the screed 3 is described. However, a control method is not limited to the above control method, and one actuator may drive at least one component selected from the group consisting of the tractor 1, the conveyor, the screw, and the screed 3.

[0060] The rear-wheel driving pump 14R is a variable displacement pump that supplies the rear wheel drive unit F1 with a hydraulic fluid for driving. In the present example, the rear-wheel driving pump 14R is a swash-plate variable displacement bidirectional hydraulic pump used in a closed hydraulic circuit (hydrostatic transmission (HST)), and a discharge amount of the hydraulic fluid from the rear-wheel driving pump 14R is regulated by a pump regulator 15. Strictly speaking, the discharge amount is a discharge amount per rotation of the pump, and is also referred to as a displacement volume.

[0061] The pump regulator 15 is a device that controls the discharge amount of the rear-wheel driving pump 14R. In the present example, the pump regulator 15 adjusts the discharge amount of the rear-wheel driving pump 14R according to a pump command current from the controller 30 of the asphalt finisher 100. For example, the discharge amount of the rear-wheel driving pump 14R is increased as the current value of the command current increases.

[0062] The charge pump 14C is a fixed displacement hydraulic pump that supplies the rear wheel drive unit F1 with a hydraulic fluid for controlling.

[0063] The conveyor-screw pump 14S is a variable displacement pump that supplies the conveyor-screw drive unit F2 with a hydraulic fluid. In the present example, the conveyor-screw pump 14S is a swash-plate variable displacement hydraulic pump. In the present example, a discharge amount of the conveyor-screw pump 14S is regulated by a pump regulator 15A. The pump regulator 15A adjusts the discharge amount of the conveyor-screw pump 14S according to a pump command current from the controller 30. For example, the discharge amount of the conveyor-screw pump 14S is increased as the current value of the pump command current increases.

[0064] The rear wheel drive unit F1 is a functional component that drives rear wheels of the tractor 1. In the present example, the rear wheel drive unit F1 includes a left rear-wheel driving motor 20L and a right rear-wheel driving motor 20R.

[0065] The left rear-wheel driving motor 20L is a hydraulic motor that drives a left rear wheel 5 (see FIG. 1) of the tractor 1. Moreover, the right rear-wheel driving motor 20R is a hydraulic motor that drives a right rear wheel 5 (see FIG. 1) of the tractor 1. In the present example, the left rear-wheel driving motor 20L and the right rear-wheel driving motor 20R are variable displacement motors, and form a closed hydraulic circuit (HST) together with the rear-wheel driving pump 14R. The left rear-wheel driving motor 20L and the right rear-wheel driving motor 20R may be fixed displacement motors. The rear-wheel driving pump 14R is connected to the left rear-wheel driving motor 20L and the right rear-wheel driving motor 20R via pipe lines C1 and C2 through which a hydraulic fluid flows.

[0066] A reduction-ratio control device 21L is a device that controls a reduction ratio of a reduction gear linked with the left rear-wheel driving motor 20L. In the present example, the reduction-ratio control device 21L adjusts the reduction ratio of the reduction gear linked with the left rear-wheel driving motor 20L using a hydraulic fluid discharged by the charge pump 14C according to a control command from the controller 30. The same applies to a reduction-ratio control device 21R that adjusts a reduction ratio of a reduction gear linked with the right rear-wheel driving motor 20R.

[0067] A brake control device 22L is a device that controls a braking force of a left rear wheel brake that brakes the left rear wheel 5 of the asphalt finisher 100. In the present example, the brake control device 22L adjusts the braking force of the left rear wheel brake using a hydraulic fluid discharged by the charge pump 14C according to a control command from the controller 30. The same applies to a brake control device 22R that adjusts a braking force of a right rear wheel brake.

[0068] The conveyor-screw drive unit F2 is a functional component that drives the conveyor and the screw. In the present example, the conveyor-screw drive unit F2 mainly includes a left screw motor 42SL, a right screw motor 42SR, a left conveyor motor 42CL, a right conveyor motor 42CR, and a conveyor-screw valve 41.

[0069] Each of the left screw motor 42SL, the right screw motor 42SR, the left conveyor motor 42CL, and the right conveyor motor 42CR is a fixed displacement motor that forms an open circuit.

[0070] The conveyor-screw valve 41 includes a conveyor control valve and a screw control valve. The conveyor control valve switches in response to a control command from the controller 30. A hydraulic fluid discharged from the conveyor-screw pump 14S flows into a suction port of the left conveyor motor 42CL, a suction port of the right conveyor motor 42CR, or both. The hydraulic fluid flown out from the suction port of the left conveyor motor 42CL, the suction port of the right conveyor motor 42CR, or both is discharged to a hydraulic fluid tank T. The screw control valve switches in response to a control command from the controller 30. A hydraulic fluid discharged from the conveyor-screw pump 14S flows into a suction port of the left screw motor 42SL, a suction port of the right screw motor 42SR, or both. The hydraulic fluid discharged from the suction port of the left screw motor 42SL, the suction port of the right screw motor 42SR, or both is discharged to the hydraulic fluid tank T.

[0071] The power supply system mainly includes a power supply connector 70 (one example of a power supply unit), a battery 71, a drive control unit 72, and a detection sensor 73. The battery 71 is as described above, thus description thereof is omitted here.

[0072] The detection sensor 73 is a sensor that detects whether it is possible to perform power supply between the power supply connector 70 and the truck-side power supply connector 203. The detection sensor 73 of the present embodiment detects whether the power supply connector 70 is connected to the truck-side power supply connector 203. The detection sensor 73 can be any sensor. For example, the detection sensor 73 may be an imaging device capable of detecting whether the truck-side power supply connector 203 is in the connectable position.

[0073] As illustrated in FIG. 3, the power supply connector 70 and the drive control unit 72 are connected with each other via an electric power line 75A for supplying electric power. The drive control unit 72 and the battery 71 are connected with each other via an electric power line 75B for supplying electric power to the battery 71 or receiving electric power supplied from the battery 71. The drive control unit 72 and the electric motor 7 for pumps are connected with each other via an electric power line 75C for supplying electric power from the battery 71 to the electric motor 7 for pumps.

[0074] The power supply connector 70 (one example of the power supply unit) can be connected to the truck-side power supply connector 203 of the dump truck 200, and can receive electric power supplied from the dump truck 200 (one example of the external device). In the case where the power supply connector 70 is connected to the truck-side power supply connector 203, for example, electric power from the battery 204 mounted on the dump truck 200 is supplied to the battery 71 of the asphalt finisher 100 via the electric power line 75A and the electric power line 75B.

[0075] A connection method between the power supply connector 70 and the truck-side power supply connector 203 may be any method. The connection method between the power supply connector 70 and the truck-side power supply connector 203 may use a contact connection or non-contact connection system. For example, power supply may be performed in a non-contact manner by bringing the power supply unit of the dump truck 200 and the power supply unit of the asphalt finisher 100 close to each other by a predetermined distance. In the case where the non-contact power supply is possible, the electric power line 75A and the electric power line 75B may not be provided.

[0076] The drive control unit 72 includes a controller 720, and performs drive control of the asphalt finisher 100.

[0077] Moreover, the drive control unit 72 may include an inverter for controlling driving (e.g., rotational speed) of the electric motor 7 for pumps when the electric power from the battery 71 is supplied to the electric motor 7 for pumps. Further, the drive control unit 72 may include a converter for controlling charging and discharging of the battery 71 (e.g., reduction in voltage of the electric power supplied from the dump truck 200).

[0078] The controller 720 includes a contact detection unit 721, a charge rate detection unit 722, a charging control unit 723, and an abnormality detection unit 724, and controls charging of the battery 71 with the electric power supplied from the battery 204 of the dump truck 200.

[0079] The contact detection unit 721 detects whether the truck-side power supply connector 203 is connected to the power supply connector 70 based on a signal input from the detection sensor 73.

[0080] The charge rate detection unit 722 detects SOC (charge rate) of the battery 71.

[0081] When the contact detection unit 721 detects that the power supply connector 70 and the truck-side power supply connector 203 are connected with each other (power supply from the truck-side power supply connector 203 to the power supply connector 70 becomes possible), the charging control unit 723 controls charging of the battery 71 with the electric power supplied from the battery 204 of the dump truck 200. Moreover, the charging control unit 723 may adjust an amount of electric power to be supplied by transmitting information to and receiving information from the controller of the dump truck 200 through wireless communication.

[0082] The abnormality detection unit 724 detects whether any abnormality has occurred in charging of the battery 71. For example, the abnormality detection unit 724 may detect whether the battery 71 is overcharged based on the SOC detected by the charge rate detection unit 722 and the control state of the charging control unit 723. In the case where the abnormality detection unit 724 has detected overcharging, the abnormality detection unit 724 may instruct the charging control unit 723 to stop charging.

[0083] Moreover, in the case where the abnormality detection unit 724 detects that abnormality has occurred, the abnormality detection unit 724 may notify an operator of the asphalt finisher 100 that the abnormality has occurred with sounds or the like.

[0084] FIGS. 4A and 4B are explanatory views of a scene where the dump truck 200 of the present embodiment is reversed to the vicinity of the asphalt finisher 100. FIG. 4A is a left side view, and FIG. 4B is a top view.

[0085] In the example illustrated in FIGS. 4A and 4B, the asphalt finisher 100 is moved by the tractor 1 in the X-axis positive direction (one example of a predetermined travel direction). Then, the asphalt finisher 100 lays and levels a pavement material in a vehicle width direction over a road surface in a position that is behind the tractor 1 and in front of the screed 3, while traveling.

[0086] The dump truck 200 depicts an example in which the dump truck 200 approaches the docking position that is at the X-axis positive direction side of the asphalt finisher 100, while the asphalt finisher 100 lays and levels the paving material simultaneously with traveling of the asphalt finisher 100 in the X-axis positive direction. The docking position of the dump truck 200 is, for example, a position where the rear wheels 206 of the dump truck 200 come in contact with the push roller 2b of the asphalt finisher 100. The docking position of the dump truck 200 is not limited to the position where the rear wheels come into contact with the push roller 2b, and the rear wheels may not be in contact with the push roller 2b as long as the dump truck 200 is close enough to supply the paving material on the bed 201 to the hopper 2.

[0087] In the present embodiment, a worker may guide the dump truck 200 to dock the dump truck 200 on the front side (the X-axis positive direction side) of the travel direction of the asphalt finisher 100. In order to dock the dump truck 200 on the front side of the asphalt finisher 100, further, communication between the asphalt finisher 100 and the dump truck 200 or the like is performed to automatically guide the dump truck 200. In this case, the speed of the dump truck 200 is controlled based on the speed of the asphalt finisher 100, while part of the bed 201 of the dump truck 200 and part of the hopper of the asphalt finisher 100 are maintained to be overlapped. To this end, information (e.g., a speed command to travel at the same speed) may be transmitted and received between the dump truck 200 and the asphalt finisher 100. In the manner as described above, the position of the dump truck 200 may be controlled to maintain a predetermined distance with the asphalt finisher 100.

[0088] After docking the dump truck 200 on the front side (the +X-axis positive direction side) of the asphalt finisher 100 in the travel direction as illustrated in FIG. 4A, the dump truck 200 raises the bed 201 using the hydraulic cylinder 250 to supply the paving material to the hopper 2 of the asphalt finisher 100.

[0089] When the dump truck 200 is docked on the front side of the asphalt finisher 100, the power supply connector 70 of the asphalt finisher 100 and the truck-side power supply connector (truck-side power supply unit) 203 of the dump truck 200 are connected to each other so that power supply can be performed.

[0090] Specifically, the power supply connector 70 is arranged in the position at which the power supply connector 70 can be connected to the truck-side power supply connector 203 disposed at the rear side of the dump truck, when the dump truck 200 comes into contact with the front side of the asphalt finisher 100. For example, in order to electrically connect the power supply connector 70 with the truck-side power supply connector 203 of the dump truck 200, the power supply connector 70 is mounted on the front side of the hopper 2 (side of the X-axis positive direction).

[0091] In addition, the height 401A of the power supply connector 70 of the asphalt finisher 100 from the ground surface in the vertical direction (Z-axis direction) is approximately equal to the height 401D of the truck-side power supply connector 203 of the dump truck 200 from the ground surface in the vertical direction (Z-axis direction).

[0092] Similarly, the position 402A of the power supply connector 70 of the asphalt finisher 100 from the center line in the vehicle width direction (Y-axis direction) is approximately equal to the position 402D of the truck-side power supply connector 203 of the dump truck 200 from the center line in the vehicle width direction (Y-axis direction).

[0093] Thus, the power supply connector 70 and the truck-side power supply connector 203 are connected on a plane indicated by a line 403. While the screed 3 lays and levels the paving material simultaneously to the traveling of the asphalt finisher 100 in the travel direction (X-axis positive direction) by the tractor 1, the charging control unit 723 charges the battery 71 with electric power supplied from the battery 204 of the dump truck 200 via the power supply connector 70. The positions of the power supply connector 70 and the truck-side power supply connector 203 described in the present embodiment are merely an example, and should not be construed as limiting positions of the power supply connector 70 and the truck-side power supply connector 203. When the dump truck 200 is docked on the asphalt finisher 100, for example, a worker may connect the power supply connector 70 and the truck-side power supply connector 203 with a charging cable or the like.

[0094] As a modification example, when the dump truck 200 approaches the asphalt finisher 100, a worker may carry out an operation of connecting the power supply connector 70 and the truck-side power supply connector 203 with a charging cable as described above. This enables supply of electric power from the dump truck 200 to the asphalt finisher 100. A length of the charging cable may be any length as long as electric power can be supplied to the asphalt finisher 100 while the dump truck 200 is traveling. In the present modification example, moreover, a dump truck that supplies a paving material to the asphalt finisher 100 may be different from a dump truck that supplies electric power to the asphalt finisher 100. For example, while the dump truck that supplies a paving material to the asphalt finisher 100 is docked on the front side of the asphalt finisher 100, the dump truck that supplies electric power may be connected to the asphalt finisher 100 with a charging cable and may supply electric power to the asphalt finisher 100 from a position set apart from the asphalt finisher 100 by the length of the charging cable. A device connected to the asphalt finisher 100 with the charging cable is not limited to the dump truck 200 as long as it is an external device that can travel parallel to the asphalt finisher 100.

[0095] When the dump truck 200 finishes supplying the paving material to the hopper 2 of the asphalt finisher 100, the charging control unit 723 determines whether SOC (charge rate) of the battery 71 detected by the charge rate detection unit 722 is lower than a set reference value. The set reference value is a value determined according to an embodiment, for example, a value at which the asphalt finisher 100 can operate until a subsequent dump truck 200 comes into contact.

[0096] In the case where the charging control unit 723 determines that the SOC (charge rate) of the battery 71 detected by the charge rate detection unit 722 is higher than the set reference value, supply of electric power from the dump truck 200 is stopped. Then, the dump truck 200 leaves the asphalt finisher 100 and starts moving toward the plant 300.

[0097] In the case where the charging control unit 723 determines that the SOC (charge rate) of the battery 71 detected by the charge rate detection unit 722 is lower than the set reference value, the charging control unit 723 requests the dump truck 200 to continue to be in contact with the asphalt finisher 100. A method of requesting the continuation of contact may be any method. The continuation request may be performed by output of a sound, or the request may be made to a driver of the dump truck 200 using wireless communication.

[0098] Then, the charging control unit 723 continues charging of the battery 71 with electric power from the battery 204 of the dump truck 200. When the charging control unit 723 determines that SOC of the battery 71 has reached the set reference value or higher, supply of electric power from the dump truck 200 is stopped. Then, the dump truck 200 leaves the asphalt finisher 100 and starts moving toward the plant 300.

[0099] In the above embodiment, the example where the dump truck 200 charges the battery 204 at the plant 300 is described. However, the present embodiment does not limit the method of supplying electric power to the dump truck 200. For example, the dump truck 200 may be supplied with power from an overhead wire while traveling or while in contact with the asphalt finisher 100.

[0100] Moreover, power supply to the battery 71 of the asphalt finisher 100 is not limited to the embodiment where electric power is supplied from the battery 204 of the dump truck 200. For example, the power supply connector 70 of the asphalt finisher 100 may supply power to the battery 71 at a power supply station before work starts. Further, the power supply connector 70 of the asphalt finisher 100 may receive electric power directly from an overhead wire or the like that supplies electric power.

[0101] In the case where the SOC of the battery 204 of the dump truck 200 becomes lower than the set value while supplying electric power to the asphalt finisher 100, the dump truck 200 may stop power supply from the battery 204 to the battery 71 of the asphalt finisher 100. The set value is, for example, a value at which the dump truck 200 can move to a position where the dump truck 200 can receive power supply. This can avoid a situation such that the dump truck 200 becomes immobile before reaching the position where the dump truck 200 can receive power supply.

Second Embodiment

[0102] In the above embodiment, the example where charging of the battery 204 of the dump truck 200 is performed when loading of the paving material from the plant 300 to the dump truck 200 is performed is described. However, the above embodiment should not be construed as limiting the method of charging the dump truck 200 at the plant 300. In the second embodiment, an example where the dump truck 200 has a power generation function instead of being charged at the plant 300 will be described.

[0103] The power generation function provided to the dump truck 200 of the present embodiment may be implemented by any method regardless of any embodiment known in the related art. For example, the dump truck 200 may include a fuel cell. As a fuel mounted as a fuel for the fuel cell, for example, hydrogen is used. In this case, the dump truck 200 generates power through a chemical reaction between hydrogen and oxygen when the dump truck 200 is controlled to supply a stored hydrogen gas to a fuel cell. Then, the electric power generated by the dump truck 200 may be supplied to the asphalt finisher 100.

[0104] The dump truck 200 includes a storage module for storing a hydrogen gas together with the fuel cell. When loading of the paving material from the plant 300 to the dump truck 200 is performed, the dump truck 200 may receive supply of a hydrogen gas from the plant 300. Then, the dump truck 200 stores the supplied hydrogen gas in the storage module.

[0105] Thereafter, the dump truck 200 supplies the paving material to the hopper 2 of the asphalt finisher 100 when the dump truck 200 is docked on the front side (the +X-axis direction side) of the asphalt finisher 100 in the travel direction. At this time, the power supply connector 70 of the asphalt finisher 100 and the truck-side power supply connector (truck-side power supply unit) 203 of the dump truck 200 are connected to each other so that power supply can be performed, and the electric power generated by the fuel cell of the dump truck 200 is supplied to the asphalt finisher 100.

[0106] In the present embodiment, the example where the fuel cell is used as the power generation function of the dump truck 200 has been described. However, the power generation function of the dump truck 200 is not limited to the fuel cell. For example, a hydrogen engine or an engine driven by an e-fuel or a biofuel may be mounted on the dump truck 200. The dump truck 200 may drive the engine and operate the power generation device by the driving of the engine. The electric power generated by the power generator is supplied to the asphalt finisher 100. In the present embodiment, the dump truck 200 replenishes a fuel, such as hydrogen or the like, at the plant 300. In this case, the dump truck 200 can shorten the period in which the dump truck 200 is stopped compared to the case where the dump truck 200 is charged at the plant 300. Thus, the dump truck 200 can efficiently supply electric power to the asphalt finisher 100.

Modification Example 1

[0107] In the above embodiment, the embodiment where the asphalt finisher 100 charges the battery 71 with electric power supplied from the dump truck 200 has been described. However, the above embodiment should not be construed as limiting the embodiment to an embodiment where electric power supplied from the dump truck 200 is used only for charging the battery 71. Therefore, in the present modification example, another embodiment of use of electric power supplied from the dump truck 200 will be described.

[0108] For example, in the case where the charging control unit 723 determines that SOC (charge rate) of the battery 71 detected by the charge rate detection unit 722 is higher than the set reference value, the asphalt finisher 100 is controlled to supply both electric power supplied from the dump truck 200 and electric power supplied from the battery 71 to the electric motor 7 for pumps. In the case where the charging control unit 723 determines that the SOC (charge rate) of the battery 71 detected by the charge rate detection unit 722 is higher than the set reference value, moreover, the charging control unit 723 may perform control such that only electric power supplied from the dump truck 200 is supplied to the electric motor 7 for pumps.

[0109] When the electric motor 7 for pumps is driven, the electric power supplied from the dump truck 200 is used so that consumption of electric power of the battery 71 can be minimized. Therefore, the operation time of the asphalt finisher 100 can be extended. Moreover, deterioration of the battery 71 can be inhibited.

[0110] As another example, in the case where the charging control unit 723 determines that the SOC (charge rate) of the battery 71 detected by the charge rate detection unit 722 is lower than the set reference value, the asphalt finisher 100 is controlled so that the electric power supplied from the dump truck 200 is supplied to the electric motor 7 for pumps, as well as charging the battery 71.

[0111] Accordingly, even when the SOC of the battery 71 is low, disruption to the operation of the asphalt finisher 100, such as laying and leveling of the paving material, can be avoided by supplying the electric power supplied from the dump truck 200 to the electric motor 7 for pumps as well as charging the battery 71 with the electric power supplied from the dump truck 200.

[0112] In the present modification example, as described above, the electric power supplied from the dump truck 200 to the asphalt finisher 100 needs to be changed depending on the situation. Therefore, the charging control unit 723 adjusts an amount of electric power to be supplied according to the situation by transmitting and receiving information to and from the controller of the dump truck 200 through wireless communication. This allows the asphalt finisher 100 to minimize reduction in SOC of the battery 71 as well as avoiding disruption to an operation of the asphalt finisher 100.

Modification Example 2

[0113] In the above embodiment and modification example, the example where the asphalt finisher 100 includes the battery 71 has been described. In Modification Example 2, an example where the asphalt finisher 100 does not include the battery 71 will be described.

[0114] Specifically, the asphalt finisher 100 of the present modification example does not include the battery 71, and illustrates an example in which the asphalt finisher 100 operates with electric power supplied from the dump truck 200. The connection method between the dump truck 200 and the asphalt finisher 100 may be a method of any embodiment. The dump truck 200 and the asphalt finisher 100 may be connected with a charging cable or the like.

[0115] In the present modification example, electric power supplied from the dump truck 200 is supplied to the electric motor 7 for pumps of the asphalt finisher 100. Then, the electric motor 7 for pumps drives the rear-wheel driving pump 14R, the charge pump 14C, and the conveyor-screw pump 14S with the electric power supplied from the dump truck 200.

[0116] Thus, the asphalt finisher 100 can lay and level the paving material without the battery 71.

[0117] In the present modification example, the asphalt finisher 100 may include a battery (e.g., a 24 V weak power battery) for supplying electric power to auxiliary machines of the asphalt finisher 100 and the like, as long as the battery 71 for supplying electric power to the electric motor 7 for pumps is not provided.

[0118] In the above embodiment and modification example, the example where the asphalt finisher 100 is driven by operation of the operator has been described. The driving of the asphalt finisher 100 includes, for example, control for traveling the asphalt finisher 100, and laying and leveling a paving material, and the like. However, in the above embodiment and modification example, the driving of the asphalt finisher 100 is not limited to the operation performed by the operator, and may be performed by automatic control. For example, the controller 30 of the asphalt finisher 100 may store information regarding travel paths of the asphalt finisher 100 and drive control may be automatically performed according to the information.

[0119] Similarly, in the above embodiment and modification example, the example where the dump truck 200 is driven by operation of the operator has been described. However, in the above embodiment and modification example, the driving of the dump truck 200 is not limited to the operation performed by the operator and may be performed by automatic control. For example, the controller (not illustrated) of the dump truck 200 may perform automatic control so that the dump truck 200 reciprocates between the plant 300 and the asphalt finisher 100. Moreover, the controller (not illustrated) of the dump truck 200 may automatically control supplying of electric power to the asphalt finisher 100 according to SOC of the battery 71 of the asphalt finisher 100 and SOC of the battery 204 of the dump truck 200.

Modification Example 3

[0120] As a method of docking the dump truck 200 on the front side of the asphalt finisher 100, any method may be used. As one example of the method, autonomous control may be performed when the dump truck 200 is docked. In the present modification example, a case where docking of the dump truck 200 is autonomously controlled will be described.

[0121] FIGS. 5A and 5B are explanatory views illustrating a state before the dump truck 200 of the present modification example is docked on the asphalt finisher 100. FIG. 5A is a left side view and FIG. 5B is a top view.

[0122] The asphalt finisher 100 according to the present modification example includes a wireless communication device 40 and an imaging device 62.

[0123] The wireless communication device 40 performs wireless communication with a device existing in the surroundings of the asphalt finisher 100, such as a dump truck 200 or the like. In the present embodiment, as a wireless communication standard of the wireless communication device 40, for example, Wi-Fi (registered trademark) may be used. The wireless communication of the present embodiment is not limited to the method using Wi-Fi (registered trademark), and wireless LAN, Bluetooth (registered trademark), or the like may be used.

[0124] The imaging device 62 is a device that acquires an image of a space in front of the asphalt finisher 100. In the present embodiment, the imaging device 62 is a camera, and outputs the acquired image to the controller 30. The imaging device 62 may be LIDAR, a range image camera, an infrared camera, a stereo camera, or the like. In the present embodiment, the example where the imaging device 62 is used as one example of a device capable of recognizing a space is described. However, the present embodiment should not be construed as limiting the space recognition device to the imaging device 62. Specifically, any space recognition device that can recognize a space with reference to the asphalt finisher 100 may be used. For example, a laser sensor or the like may be used.

[0125] The imaging device 62 according to the present embodiment captures an image of a space within an imaging region RA1 indicated with a dot dash line in FIGS. 5A and 5B, which is present in front of the asphalt finisher 100. The imaging device 62 outputs image information regarding the captured image to the controller 30. In the example illustrated in FIGS. 5A and 5B, the imaging device 62 can capture an image of the dump truck 200 in the imaging region RA1.

[0126] In addition to the configuration illustrated in FIG. 1, the dump truck 200 includes a first imaging device 261, a second imaging device 262, a controller 230, and a wireless communication device 240.

[0127] The first imaging device 261 is a device that acquires an image of a space in front of the dump truck 200. The second imaging device 262 is a device that acquires an image of a space behind the dump truck 200. The first imaging device 261 and second imaging device 262 according to the present embodiment are cameras, and output acquired images to the controller 230. The first imaging device 261 and second imaging device 262 may be LIDARs, range image cameras, infrared cameras, stereo cameras, or the like. The present embodiment describes the example in which the first imaging device 261 and the second imaging device 262 are used as one example of the device capable of recognizing a space. However, the present embodiment should not be construed as limiting the space recognition device to the first imaging device 261 and the second imaging device 262. Specifically, any space recognition device capable of recognizing a space with reference to the dump truck 200 may be used. For example, a laser sensor or the like may be used.

[0128] The first imaging device 261 according to the present embodiment captures an image of a space in an imaging region RT1 indicated with a two-dot dash line in FIGS. 5A and 5B, which is present at the front of the dump truck 200. The first imaging device 261 outputs the image information regarding the captured image to the controller 230.

[0129] The second imaging device 262 according to the present embodiment captures an image of a space within an imaging region RT2 indicated with a two-dot dash line in FIGS. 5A and 5B, which is present behind the dump truck 200. The second imaging device 262 outputs the image information regarding the captured image to the controller 230.

[0130] The wireless communication device 240 performs wireless communication with a device existing in the surroundings of the dump truck 200, such as the asphalt finisher 100 or the like. In the present embodiment, as a wireless communication standard of the wireless communication device 240, for example, Wi-Fi (registered trademark) may be used. The wireless communication of the present embodiment is not limited to the method using Wi-Fi (registered trademark), and wireless LAN, Bluetooth (registered trademark), or the like may be used.

[0131] The controller 230 is a control device that controls the dump truck 200. The controller 230 includes, for example, a computer that includes a central processing unit (CPU), internal memory, and a recording medium. The controller 230 causes the CPU to execute one or more programs stored in the recording medium to implement a variety of control.

[0132] The controller 230 according to the present embodiment can assist driving operation according to advanced driver-assistance systems (ADAS) based on the image information received from the first imaging device 261, the image information receiving from the second imaging device 262, and detection signals received from various detection sensors (not illustrated). The driving operation assistance system that the controller 230 of the present embodiment uses is not limited to the driving operation assistance system of ADAS, and may be another driving operation assistance system. For example, the controller 230 may use autonomous driving (AD). Further, the controller 230 may use any system as long as the system is a system capable of controlling the dump truck 200 to travel to the vicinity of the hopper 2 of the asphalt finisher 100.

[0133] The controller 230 according to the present embodiment implements control of stopping the dump truck 200 in the vicinity of the hopper 2 of the asphalt finisher 100 using the parking assistance of ADAS. At this time, the controller 230 of the present embodiment receives a control demand from the asphalt finisher 100 via the wireless communication device 240, and implements driving control of the dump truck 200 based on the received control command.

[0134] In order to connect the truck-side power supply connector 203 of the dump truck 200 with the power supply connector 70 of the asphalt finisher 100, positioning of the truck-side power supply connector 203 and the power supply connector 70 needs to be performed. For example, in the case where the power supply connector 70 of the asphalt finisher 100 and the truck-side power supply connector 203 of the dump truck 200 are misaligned in a lateral direction, the steering angle of the dump truck 200 needs to be adjusted.

[0135] The misalignment in the lateral direction can be determined, for example, from the image captured by the imaging device 62 of the asphalt finisher 100.

[0136] In the present embodiment, the controller 30 of the asphalt finisher 100 generates a control demand for adjusting the steering angle of the dump truck 200 or the like based on the image information from the imaging device 62.

[0137] The controller 230 generates a control command related to driving control based on the image information from the first imaging device 261, the image information from the second imaging device 262, control signals from detection sensors (not illustrated), or the like. Then, the controller 230 outputs the generated control demand to a driving system controller (not illustrated). Thus, the controller 230 implements the driving operation assistance with ADAS.

[0138] In the case where the controller 230 receives a control demand from the asphalt finisher 100 via the wireless communication device 240, the controller 230 outputs the received control demand to the driving system controller (not illustrated). Thus, the controller 230 implements the driving operation assistance for the dump truck 200 with ADAS in response to the request from the asphalt finisher 100.

[0139] In the present embodiment, the imaging device 62 is disposed on the asphalt finisher 100 in a manner such that an optical axis of the imaging device 62 overlaps the center line of the asphalt finisher 100 in the travel direction in a top view. When the dump truck 200 reverses such that the center line of the dump truck 200 overlaps the center line of the asphalt finisher 100 in a top view, the truck-side power supply connector 203 of the dump truck 200 can be connected to the power supply connector 70.

[0140] For this purpose, the controller 30 determines whether a section of the image corresponding to the center position of the dump truck 200 is laterally misaligned with the center of the image captured by the imaging device 62. Thus, the controller 30 determines whether the truck-side power supply connector 203 of the dump truck 200 can be connected to the power supply connector 70.

[0141] The present modification example merely describes one example of the method of determining whether the truck-side power supply connector 203 of the dump truck 200 captured on the image can be connected to the power supply connector 70, and another method may be used. For example, whether the truck-side power supply connector 203 of the dump truck 200 can be connected to the power supply connector 70 may be determined from the left and right ends of the dump truck 200.

[0142] The controller 30 generates a control demand for controlling a transport vehicle (e.g., the dump truck 200) detected on the image (one example of detection information) captured by the imaging device 62. The generated control demand includes, for example, a steering command to the right or left, a deceleration command, a braking command, or the like. The control commands that the controller 30 generates are not limited to the above commands, and may be various other control commands. For example, control commands that the controller 30 generates may be any command executable by ADAS or the like, such as turning-on or turning-off of a headlight, warning to a driver, or the like.

[0143] The controller 30 of the present embodiment generates a control command based on a result of determination whether the truck-side power supply connector 203 of the dump truck 200 can be connected to the power supply connector 70. The control command includes, for example, a control command for steering the dump truck 200 so that the truck-side power supply connector 203 of the dump truck 200 is connected to the power supply connector 70. Other control commands include, for example, a control command that instructs the dump truck 200 to reverse or stop so that the rear wheels 206 of the dump truck 200 come into contact with the push roller 2b. In the present modification example, when the rear wheels 206 of the dump truck 200 are brought into contact with the push roller 2b, the truck-side power supply connector 203 and the power supply connector 70 are connected to each other. Thus, electric power can be supplied from the dump truck 200 to the asphalt finisher 100.

[0144] Moreover, the controller 30 generates a control command related to stopping or deceleration based on a positional relationship between the rear wheels 206 of the dump truck 200 and the push roller 2b of the asphalt finisher 100 specified based on the image information from the imaging device 62.

[0145] The controller 30 performs communication control with a transport vehicle, such as the dump truck 200, via the wireless communication device 40. Thus, the controller 30 can transmit a control demand to the dump truck 200. For example, the controller 30 transmits a control demand to the wireless communication device 240 of the dump truck 200.

[0146] The present modification example merely describes one embodiment of the autonomous control when the dump truck 200 is docked on the asphalt finisher 100, and another embodiment may be used. For example, the controller 230 of the dump truck 200 may perform steering control based on the image information transmitted from the asphalt finisher 100 or the image information of the second imaging device 262, instead of transmitting a control demand from the asphalt finisher 100.

<Functions>

[0147] In the above embodiment, the asphalt finisher 100 can charge the battery 71 with electric power supplied from the battery 204 of the dump truck 200. Thus, disruption to operation of the asphalt finisher 100 due to reduction in SOC of the battery 71 can be avoided while the asphalt finisher 100 is spreading the paving material.

[0148] Since electric power is sequentially supplied from the dump truck 200 to the asphalt finisher 100, a capacity of the battery 71 can be reduced, or the asphalt finisher 100 may not include the battery 71. Thus, an increase in weight of the asphalt finisher 100 can be avoided, and cost reduction can be achieved.

[0149] Moreover, the asphalt finisher 100 continues to receive power supply from the battery 204 of the dump truck 200 according to SOC of the battery 71 so that disruption to operation of the asphalt finisher 100 in the middle of work can be avoided. This can improve safety.

[0150] Further, the power supply connector 70 of the asphalt finisher 100 is arranged in a position corresponding to the truck-side power supply connector 203 of the dump truck 200 when the dump truck 200 is in contact with the asphalt finisher 100. This can reduce the load of connecting the power supply connector 70 and the truck-side power supply connector 203 with each other.

[0151] The above asphalt finisher 100 can be driven by electric power supplied from an external device, such as the dump truck 200 or the like. Thus, the asphalt finisher 100 can perform work in an environmentally friendly manner as compared with an asphalt finisher using an internal combustion engine.

[0152] In the above embodiment, the example where electric power supplied from the battery 71 generates rotational power of the electric motor 7 for pumps (one example of the actuator), and the rotational power of the electric motor 7 for pumps drives the rear-wheel driving pump 14R, the charge pump 14C, and the conveyor-screw pump 14S has been described. However, the above embodiment is not limited to such a configuration. As a modification example, at least one component selected from the group consisting of the rear-wheel driving pump 14R, the charge pump 14C, and the conveyor-screw pump 14S may be replaced with an electric actuator (e.g., a pump motor). In the case of this modification example, electric power is supplied from the battery 71 to the replacing electric actuator (e.g., the pump motor). In this configuration, similarly to the above embodiment, the battery 71 can be charged with electric power supplied from the battery 204 of the dump truck 200. Accordingly, the same effects as the effects of the above embodiment can be achieved.

[0153] Although the embodiments of the asphalt finisher and the power supply system for asphalt finisher have been described above, the present disclosure is not limited to the above embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. Such modifications are also included in the technical scope of the present disclosure. It is needless to say that such changes, modifications, substitutions, additions, deletions, and combinations are also within technical scope of the present disclosure.