WO2024150639A1 - Electric work machine, electric work machine control system, and electric work machine control method - Google Patents

Abstract

In the present invention, a battery (31) is charged by a charging facility (50). A travelling body (5) travels by means of electric power supplied from the battery (31). A position sensor (21) acquires position information of an electric excavator (100). A controller (40): calculates a clearance distance between the charging facility (50) and the electric excavator (100) on the basis of position information of the charging facility (50) and position information of the electric excavator (100) acquired by the position sensor (21); calculates a required electricity amount required for movement by the clearance distance; and outputs notification information when the required electricity amount has been determined to be equal to or more than a storage battery residual amount stored in the battery (31).

Description

Electric working machine, control system for electric working machine, and control method for electric working machine

This disclosure relates to an electric work machine, a control system for an electric work machine, and a control method for an electric work machine.

There are electric work machines that run (move) using power supplied from a battery. In such electric work machines, if the remaining battery power falls below the power required to travel to the charging facility, the work machine may be unable to reach the charging facility on its own.

In response to this, in JP 2020-159055 A (Patent Document 1), when the remaining battery charge falls below a preset threshold, the driving motor is switched to the first driving speed regardless of the input from the driving mode instruction device.

In addition, in JP 2020-125625 A (Patent Document 2), the battery loss when the work machine travels from the charging facility to the work site is calculated, and a warning threshold is set based on the value obtained by adding this battery loss to the battery remaining limit.

JP 2020-159055 A JP 2020-125625 A

However, in the above-mentioned patent documents 1 and 2, the exact amount of electricity required to reach the charging facility is not known.

The objective of this disclosure is to provide an electric work machine, an electric work machine control system, and an electric work machine control method that can determine the exact amount of electricity required to reach a charging facility.

Each of the electric work machine and the electric work machine control system disclosed herein includes a battery, a running body, a position sensor, and a controller. The battery is charged by a charging facility. The running body runs on power supplied from the battery. The position sensor acquires position information of the electric work machine. The controller calculates the distance between the charging facility and the electric work machine based on the position information of the charging facility and the position information of the electric work machine acquired by the position sensor, calculates the amount of electricity required to move the distance, and outputs notification information when it determines that the amount of electricity required is equal to or greater than the remaining battery charge stored in the battery.

The disclosed method for controlling an electric work machine includes a battery that is charged by a charging facility and a vehicle that runs on power supplied from the battery, and includes the following steps:

The distance between the charging equipment and the electric work machine is calculated based on the position information of the charging equipment and the position information of the electric work machine. The amount of electricity required to move the distance is calculated. If it is determined that the amount of electricity required is equal to or greater than the remaining battery charge stored in the battery, a notification is output.

According to the present disclosure, it is possible to realize an electric work machine, an electric work machine control system, and an electric work machine control method that can determine the exact amount of electricity required to reach a charging facility.

1 is a diagram showing a configuration of an electric working machine according to an embodiment of the present disclosure. FIG. 2 is a diagram showing functional blocks of a control system for an electric working machine according to an embodiment of the present disclosure. FIG. 3 is a diagram showing functional blocks of a controller shown in FIG. 2 . FIG. 4 is a flow chart showing a control method for an electric working machine in one embodiment of the present disclosure.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
In the specification and drawings, the same or corresponding components are denoted by the same reference numerals, and redundant explanations are not repeated. In addition, in the drawings, configurations may be omitted or simplified for the convenience of explanation.

In the following description, "up," "down," "front," "rear," "left," and "right" refer to directions based on the operator seated in the driver's seat 4S in the driver's cab 4 shown in Figure 1.

<Configuration of electric powered working machine>
As an example of the electric work machine of the present disclosure, the configuration of an electric shovel will be described with reference to Fig. 1. The electric work machine of the present disclosure may be any other work machine such as a wheel loader, a bulldozer, or a motor grader, so long as it is a work machine that runs on electric power stored in a battery.

FIG. 1 is a diagram showing a schematic configuration of an electric shovel in one embodiment of the present disclosure. As shown in FIG. 1, the electric shovel 100 of this embodiment has a main body 1 and a working machine 2. The main body 1 has a rotating body 3 and a running body 5.

The running body 5 has a pair of tracks 5Cr and a travel motor 5M. The electric excavator 100 can travel by rotating the tracks 5Cr. The travel motor 5M is provided as a drive source for the running body 5. The travel motor 5M is, for example, a hydraulic motor that is operated by hydraulic pressure. The running body 5 may also have wheels (tires).

The rotating body 3 is placed on the running body 5 and is supported by the running body 5. The rotating body 3 can rotate around a rotation axis RX relative to the running body 5 by a rotation motor (not shown). The rotation motor is, for example, a hydraulic motor that is operated by hydraulic pressure. The rotation axis RX is an imaginary straight line that is the center of rotation of the rotating body 3. The traveling motor 5M or the rotation motor may be an electric motor.

The rotating body 3 has a driver's cab 4. A driver's seat 4S is provided in the driver's cab 4 where the operator sits. The operator (crew) sits in the driver's cab 4 and can operate the work equipment 2, rotate the rotating body 3 relative to the running body 5, and operate the electric shovel 100 using the running body 5. The rotating body 3 has an exterior cover 9. The exterior cover 9 covers the machine room. The electric shovel 100 may be remotely operated.

The work machine 2 is supported by the rotating body 3. The work machine 2 has a boom 6, an arm 7, and a bucket 8. The work machine 2 further has a boom cylinder 10, an arm cylinder 11, and a bucket cylinder 12.

The boom 6 is rotatably connected to the main body 1. Specifically, the base end of the boom 6 is rotatably connected to the rotating body 3 with the boom foot pin 13 as a fulcrum. The arm 7 is rotatably connected to the boom 6. Specifically, the base end of the arm 7 is rotatably connected to the tip of the boom 6 with the boom top pin 14 as a fulcrum. The bucket 8 is rotatably connected to the arm 7. Specifically, the base end of the bucket 8 is rotatably connected to the tip of the arm 7 with the arm top pin 15 as a fulcrum.

One end of the boom cylinder 10 is connected to the rotating body 3, and the other end is connected to the boom 6. The boom 6 can be driven relative to the main body 1 by the boom cylinder 10. This drive allows the boom 6 to rotate vertically relative to the rotating body 3, with the boom foot pin 13 as a fulcrum.

One end of the arm cylinder 11 is connected to the boom 6, and the other end is connected to the arm 7. The arm 7 can be driven relative to the boom 6 by the arm cylinder 11. This drive allows the arm 7 to rotate up and down or back and forth relative to the boom 6, with the boom top pin 14 as a fulcrum.

One end of the bucket cylinder 12 is connected to the arm 7, and the other end is connected to the bucket link 17. The bucket 8 can be driven relative to the arm 7 by the bucket cylinder 12. This drive allows the bucket 8 to rotate vertically relative to the arm 7, with the arm top pin 15 as a fulcrum.

Each of the boom cylinder 10, arm cylinder 11 and bucket cylinder 12 is a hydraulic cylinder driven by hydraulic pressure, but may also be another actuator such as an electric cylinder.

The electric shovel 100 further has a position sensor 21. The position sensor 21 is, for example, a GNSS (Global Navigation Satellite Systems) receiver. The position sensor 21 includes two GNSS receivers 21a, 21b. Each of the two GNSS receivers 21a, 21b is installed at a different position on the rotating body 3. Each of the GNSS receivers 21a, 21b receives a satellite positioning signal from a satellite that indicates the position of the rotating body 3 in the global coordinate system.

The electric excavator 100 further has a surrounding information sensor 24. The surrounding information sensor 24 is attached, for example, to the top surface of the cab 4 near the front end. The surrounding information sensor 24 is arranged so that it can capture an image of, for example, the area in front of the main body 1. The surrounding information sensor 24 is arranged so that it can capture an image of, for example, the area near the cutting edge of the work machine 2 or the area near the object to be excavated.

Multiple surrounding information sensors 24 may be arranged on the main body 1. The multiple surrounding information sensors 24 may be arranged so as to be able to capture images of the front, left and right sides, and rear of the main body 1.

The surrounding information sensor 24 may be, for example, a LiDAR (Light Detection and Ranging) that emits laser light to acquire information about an object. The surrounding information sensor 24 may also be a Radar (Radio Detection and Ranging) that acquires information about an object by emitting radio waves. The radar may be, for example, a millimeter wave radar that uses a receiving antenna to detect how millimeter wave band radio waves emitted from a transmitting antenna are reflected off the surface of an object and returned. The surrounding information sensor 24 may be a visual sensor including a camera. The surrounding information sensor 24 may be an infrared sensor.

<Electric power machine control system>
Next, the control system for the electric working machine in this embodiment will be described with reference to FIG.

FIG. 2 is a diagram showing the functional blocks of a control system for an electric working machine in one embodiment of the present disclosure. In FIG. 2, one line indicates an electric circuit, two lines indicate a hydraulic circuit, and dashed lines indicate mechanical connections.

As shown in FIG. 2, the control system of the electric shovel 100, which is an electric work machine, has a position sensor 21, a receiver 22, a communication device 23, a surrounding information sensor 24, an alarm device 25, and an operating device 26.

The position sensor 21 outputs a satellite positioning signal indicating the position of the rotating body 3 in the global coordinate system received from a satellite to the controller 40. The controller 40 calculates the position of the electric excavator 100 in the global coordinate system from this satellite positioning signal.

The receiver 22 is capable of communicating with the charging equipment 50. Wireless communication between the receiver 22 and the charging equipment 50 is performed, for example, using a specific low-power radio or a wireless LAN. The receiver 22 receives position information of the charging equipment 50 from the charging equipment 50. The receiver 22 outputs a position signal indicating the received position of the charging equipment 50 to the controller 40. The controller 40 calculates the position of the charging equipment 50 in the global coordinate system based on the position signal received from the charging equipment 50.

The charging equipment 50 charges the battery 31 of the electric shovel 100. The charging equipment 50 may be a fixed type that is grounded on the ground, or may be a mobile type that is mounted on a truck or the like. The charging equipment 50 has a position sensor 51, a memory unit 52, and a transmission device 53. The position sensor 51 is, for example, a GNSS receiver. The position sensor 51 receives from a satellite a satellite positioning signal that indicates the position of the charging equipment 50 in the global coordinate system. The memory unit 52 may store the position of the charging equipment 50 received by the position sensor 51. The transmission device 53 transmits the position information of the charging equipment 50 received by the position sensor 51 or stored in the memory unit 52 to the receiver 22.

The communication device 23 is capable of communicating with the remote control device 60. The communication device 23 receives an operation signal from the remote control device 60. The communication device 23 outputs the operation signal received from the remote control device 60 to the controller 40. The communication device 23 also transmits notification information to the communication device 61 of the remote control device 60, such as a notification signal acquired from the controller 40, the working status of the electric excavator 100 detected by the surrounding information sensor 24, the current topography, and the designed topography.

The remote control device 60 is a device that allows an operator to operate the electric shovel 100 from a remote location. The remote control device 60 has, for example, a communication device 61, an operation device 62, and a display device 63 (alarm device). Each of the communication device 61, the operation device 62, and the display device 63 is disposed in a location remote from the electric shovel 100. The operator may board the electric shovel 100 to operate the electric shovel 100.

The communication device 61 can communicate wirelessly with the communication device 23. Wireless communication between the communication device 61 and the communication device 23 is performed, for example, using a specific low-power radio or a wireless LAN.

The operating device 62 includes, for example, an operating lever, an operating switch, and the like for the operator to operate. An operating signal input to the operating device 62 by the operator is received by the communication device 23 via the communication device 61 and output to the controller 40 of the electric excavator 100.

The remote operation device 60 may be a remote management device that has a communication device 61 and a display device 63, but does not have an operation device 62. In this case, various information (such as notification information) received by the communication device 61 of the remote management device 60 from the communication device 23 of the electric excavator 100 is displayed on the display device 63 of the remote management device 60. The remote management device 60 may also have a notification speaker, and may emit a sound from the notification speaker when notification information is received from the communication device 23.

The display device 63 displays various information such as notification information, the working status of the electric shovel 100, the current topography, and the designed topography. The display device 63 can display information obtained from the electric shovel 100 via the communication device 23 and the communication device 61.

The surrounding information sensor 24 outputs a signal indicating the surrounding information of the electric excavator 100 detected by the surrounding information sensor 24 to the controller 40. The controller 40 transmits this surrounding information to the alarm device 25, the display device 63 of the remote control device 60, etc.

The notification device 25 may be, for example, a display device or a notification speaker. The notification device 25 is arranged, for example, in the driver's cab 4. The display device as the notification device 25 displays, for example, notification information. The display device as the notification device 25 may also display surrounding information detected by the surrounding information sensor 24, current topography data, designed topography data, the cutting edge position of the work machine 2, etc., or construction plan data. The notification speaker emits a warning sound.

The operating device 26 is disposed in the cab 4. The operating device 26 controls the travel of the electric excavator 100, the operation of the work machine 2, the rotation of the rotating body 3, etc., and is operated by the operator. The amount of operation of the operating device 26 is detected by, for example, a potentiometer or a Hall IC (Integrated Circuit). When the operating device 26 is operated, an operation signal indicating the amount of operation of the operating device 26 is transmitted to the controller 40. The controller 40 transmits the operation signal as an operation command to the electromagnetic control valve 36 for the work machine, the electromagnetic control valve 37 for the travel motor, etc.

The battery 31 is connected to the controller 40 and the inverter 33 via electrical wiring. The controller 40 provides a control signal to the inverter 33, which is connected via electrical wiring. The battery 31 supplies power to the electric motor 34, which serves as a power source, via the inverter 33. The battery 31 is a unit made up of multiple lithium-ion battery cells, for example.

The inverter 33 converts the DC power output from the battery 31 into AC power with controlled frequency, etc., based on a control signal from the controller 40. The inverter 33 supplies the AC power to the electric motor 34 through electrical wiring. As a result, the electric motor 34 is driven by the AC power supplied from the inverter 33, using the battery 31 as a power source.

The electric motor 34 and the hydraulic pump 35 are mechanically linked. The driving force of the electric motor 34 is transmitted to the hydraulic pump 35, which drives the hydraulic pump 35. When the hydraulic pump 35 is driven, it pumps hydraulic oil from the hydraulic oil tank TA. The hydraulic pump 35 supplies and discharges the hydraulic oil pumped from the hydraulic oil tank TA to each of the work machine actuators 10, 11, and 12 through the work machine electromagnetic control valve 36. The supply and discharge of hydraulic oil operates each of the work machine actuators 10, 11, and 12. The hydraulic pump 35 also supplies and discharges the hydraulic oil pumped from the hydraulic oil tank TA to the travel motor 5M through the travel motor electromagnetic control valve 37. The supply and discharge of hydraulic oil operates the travel motor 5M.

The controller 40 controls the opening and closing of the work machine electromagnetic control valve 36. This controls the drive of each of the work machine actuators 10, 11, and 12. The controller 40 controls the opening and closing of the travel motor electromagnetic control valve 37. This controls the drive of the travel motor 5M.

The controller 40 outputs control signals to the inverter 33, the electromagnetic control valve for the work machine 36, and the electromagnetic control valve for the travel motor 37 based on the acquired operation signal. This controls the travel of the running body 5 of the electric excavator 100 and the operation of the work machine 2 based on the operation signal from the operation device 26 or the remote operation device 60.

The charge remaining sensor 32 detects the charge remaining in the battery 31. The charge remaining sensor 32 outputs a signal indicating the detected charge remaining in the battery 31 to the controller 40.

The controller 40 calculates the distance between the charging equipment 50 and the electric shovel 100 based on the position information of the charging equipment 50 and the position information of the electric shovel 100 received by the receiver 22. The controller 40 calculates the amount of electricity required to move the above-mentioned distance. The controller 40 outputs notification information when it determines that the above-mentioned required amount of electricity is equal to or greater than the remaining battery charge stored in the battery 31.

<Controller 40>
Next, the functional blocks of the controller 40 will be described with reference to FIG.

FIG. 3 is a diagram showing functional blocks of the controller shown in FIG. 2. As shown in FIG. 3, the controller 40 includes a processor, a main memory, and a storage. The processor is, for example, a CPU (Central Processing Unit). The main memory includes, for example, a non-volatile memory such as a ROM (Read Only Memory) and a volatile memory such as a RAM (Random Access Memory). The controller 40 reads out a program stored in the storage, expands it into the main memory, and executes a predetermined process according to the program.

The controller 40 may be mounted on the electric shovel 100, or may be disposed remotely outside the electric shovel 100. When the controller 40 is disposed remotely outside the electric shovel 100, the controller 40 may be wirelessly connected to each device, sensor, etc. mounted on the electric shovel 100. In this case, the controller 40 may be stored in a server separate from the electric shovel 100.

The controller 40 has a work machine position acquisition unit 41, a charging equipment position acquisition unit 42, a remaining charge acquisition unit 43, a distance calculation unit 44, a memory unit 45, a required electricity amount calculation unit 46, a movement feasibility determination unit 47, a notification control unit 48, and a travel speed limiting unit 49.

The work machine position acquisition unit 41 acquires a signal indicating the position of the electric shovel 100 in the global coordinate system from the position sensor 21. The work machine position acquisition unit 41 outputs the acquired signal indicating the position of the electric shovel 100 to the separation distance calculation unit 44.

The charging equipment position acquisition unit 42 acquires a signal indicating the position of the charging equipment 50 in the global coordinate system from the receiver 22. The charging equipment position acquisition unit 42 outputs the acquired signal indicating the position of the charging equipment 50 to the separation distance calculation unit 44. This allows the charging equipment position acquisition unit 42 to acquire the accurate position of the charging equipment 50 even if the charging equipment 50 is mobile and mounted on a truck or the like.

The remaining charge acquisition unit 43 acquires a signal indicating the remaining charge of the battery 31 from the remaining charge sensor 32. The remaining charge acquisition unit 43 outputs the acquired signal indicating the remaining charge of the battery 31 to the movement feasibility determination unit 47.

The separation distance calculation unit 44 calculates the separation distance between the charging equipment 50 and the electric shovel 100 based on the acquired signal indicating the position of the electric shovel 100 and the signal indicating the position of the charging equipment 50. The separation distance calculation unit 44 outputs the calculated separation distance to the required amount of electricity calculation unit 46.

When the charging equipment 50 is fixed and grounded, the separation distance calculation unit 44 may calculate the separation distance based on the position information of the electric excavator 100 acquired from the work machine position acquisition unit 41 and the position information of the charging equipment 50 stored in advance in the storage unit 45. In this case, the separation distance calculation unit 44 does not need to acquire a signal indicating the position of the charging equipment 50 from the charging equipment position acquisition unit 42.

The required amount of electricity calculation unit 46 calculates the amount of electricity required to move to the charging equipment 50 based on the acquired separation distance. At this time, the required amount of electricity calculation unit 46 refers to information (table) that indicates the relationship between the separation distance stored in the memory unit 45 and the amount of electricity required for the electric shovel 100 to move. The amount of electricity required for the electric shovel 100 to move is calculated in advance based on known information such as the set traveling speed, the specifications of the electric motor 34, and the efficiency and pressure loss of the hydraulic pump 35 and the traveling motor 5M. The required amount of electricity calculation unit 46 outputs a signal indicating the calculated amount of electricity required to the movement feasibility determination unit 47.

The required electricity calculation unit 46 may calculate the required electricity taking into account at least one of the slip ratio based on the soil information of the work site and the slope based on the difference in elevation between the charging equipment 50. The slip ratio based on the soil information of the work site may be calculated in advance by investigating the soil information of the work site and stored in the storage unit 45. The slip ratio based on the soil information of the work site may also be calculated from surrounding soil information detected by the surrounding information sensor 24. The slip ratio is a measure of the degree of slippage that occurs between the tracks 5Cr (or tires) and the ground when a braking force or driving force is applied. When the vehicle speed is V, the wheel angular velocity is ω, and the wheel effective radius is r, the slip ratio during driving is expressed as (V-ωr)/ωr, and the slip ratio during braking is expressed as (V-ωr)/V.

The inclination based on the difference in elevation between the electric shovel 100 and the charging equipment 50 may be calculated from the difference between the elevation position of the ground where the electric shovel 100 is located and the elevation position of the ground where the charging equipment 50 is located, and the distance between them. The position of the electric shovel 100 in the global coordinate system acquired by the position sensor 21 is used as the elevation position of the ground where the electric shovel 100 is located. The elevation position of the charging equipment 50 acquired by the receiver 22, or the elevation position of the charging equipment 50 previously stored in the memory unit 45 may be used as the elevation position of the ground where the charging equipment 50 is located.

The movement feasibility determination unit 47 determines whether or not the electric excavator 100 can move to the charging equipment 50 based on a signal indicating the required amount of electricity acquired from the required amount of electricity calculation unit 46 and a signal indicating the remaining charge acquired from the remaining charge acquisition unit 43. Specifically, the movement feasibility determination unit 47 determines whether or not the remaining charge is equal to or less than the required amount of electricity (remaining charge≦required amount of electricity). The movement feasibility determination unit 47 outputs a determination signal indicating the determination result to the notification control unit 48 and the traveling speed restriction unit 49. The movement feasibility determination unit 47 also outputs a difference signal indicating the magnitude of the difference between the required amount of electricity and the remaining charge to the notification control unit 48 and the traveling speed restriction unit 49.

The notification control unit 48 controls the notification device 25 and the display device 63 of the remote control device 60 based on the acquired determination signal and difference signal. Specifically, when the notification control unit 48 acquires a signal indicating a determination result that the remaining charge is equal to or less than the required amount of electricity from the mobility determination unit 47, it outputs a notification signal to the notification device 25 and the communication device 23.

When the alarm device 25 receives an alarm signal from the alarm control unit 48, it issues the necessary warning using an image, light, sound, or the like based on the alarm signal. The alarm device 25 may also change the output form of the warning depending on the magnitude of the difference between the required amount of electricity in the difference signal and the remaining charge. For example, when the alarm device 25 issues a warning using an image or light, it changes the color of the image or light to yellow, red, or the like. When the alarm device 25 issues a warning using sound, it changes the sound to an intermittent sound or a continuous sound.

When the communication device 23 receives the notification signal from the notification control unit 48, it transmits the notification signal to the remote control device 60. Based on the notification signal, the remote control device 60 issues a necessary warning by displaying an image on the display device 63 or by emitting a sound from a speaker or the like. As with the notification device 25, the remote control device 60 may change the output form of the warning depending on the magnitude of the difference between the required amount of electricity and the remaining charge in the difference signal.

The traveling speed limiting unit 49 controls the traveling motor electromagnetic control valve 37 based on the acquired judgment signal or difference signal. Specifically, when the traveling speed limiting unit 49 of the controller 40 acquires a judgment signal indicating that the required amount of electricity is equal to or greater than the remaining battery charge, it controls the traveling motor electromagnetic control valve 37 to limit the traveling speed of the electric shovel 100. For example, even if the operating device 26 is operated to travel at the maximum speed, when the traveling speed limiting unit 49 acquires a judgment signal indicating that the required amount of electricity is equal to or greater than the remaining battery charge, it controls the traveling motor electromagnetic control valve 37 to set a speed limit lower than the maximum speed. The speed limit can be set by adjusting the opening of the traveling motor electromagnetic control valve. The traveling speed limiting unit 49 may also control the inverter 33 based on the acquired judgment signal. For example, the traveling speed limiting unit 49 may control the inverter 33 to change the frequency given to the electric motor 34 to set the speed limit. The traveling speed limiting unit 49 may change the traveling speed limit according to the acquired difference signal.

<Method for controlling electric working machine>
Next, a control method for the electric working machine in this embodiment will be described with reference to FIGS.

FIG. 4 is a flow diagram showing a method for controlling an electric work machine in one embodiment of the present disclosure. As shown in FIGS. 3 and 4, the work machine position acquisition unit 41 acquires a signal indicating the position of the electric excavator 100 in the global coordinate system from the position sensor 21 (step S1: FIG. 4). The work machine position acquisition unit 41 outputs the acquired signal indicating the position of the electric excavator 100 to the separation distance calculation unit 44.

The charging equipment position acquisition unit 42 acquires a signal indicating the position of the charging equipment 50 in the global coordinate system from the receiver 22 (step S2: FIG. 4). The charging equipment position acquisition unit 42 outputs the acquired signal indicating the position of the charging equipment 50 to the separation distance calculation unit 44.

The remaining charge acquisition unit 43 acquires a signal indicating the remaining charge of the battery 31 from the remaining charge sensor 32 (step S3: FIG. 4). The remaining charge acquisition unit 43 outputs the acquired signal indicating the remaining charge of the battery 31 to the movement feasibility determination unit 47.

The separation distance calculation unit 44 calculates the separation distance between the charging equipment 50 and the electric shovel 100 based on the acquired signal indicating the position of the electric shovel 100 and the signal indicating the position of the charging equipment 50 (step S4: FIG. 4). The separation distance calculation unit 44 outputs the calculated separation distance to the required amount of electricity calculation unit 46.

The required amount of electricity calculation unit 46 calculates the amount of electricity required to move to the charging equipment 50 based on the acquired separation distance (step S5: FIG. 4). At this time, the required amount of electricity calculation unit 46 refers to information indicating the relationship between the separation distance stored in the memory unit 45 and the amount of electricity required for the electric excavator 100 to move. The required amount of electricity calculation unit 46 outputs a signal indicating the calculated required amount of electricity to the movement feasibility determination unit 47.

The movement feasibility determination unit 47 determines whether or not the electric excavator 100 can move to the charging facility 50 based on the acquired signal indicating the required amount of electricity and the signal indicating the remaining charge. Specifically, the movement feasibility determination unit 47 determines whether or not the remaining charge is equal to or less than the required amount of electricity (remaining charge amount≦required amount of electricity) (step S6: FIG. 4). Note that the required amount of electricity may be calculated by adding a predetermined margin to the required amount of electricity, so that notification information can be output early in step S8 described below.

If the mobility determination unit 47 determines that the remaining charge is greater than the required amount of electricity, the notification control unit 48 does not output notification information (notification signal) to the notification device 25 and the communication device 23 (step S7).

On the other hand, if the mobility determination unit 47 determines that the remaining charge is less than the required amount of electricity, the notification control unit 48 outputs notification information (notification signal) to the notification device 25 and the communication device 23 (step S8).

When the alarm device 25 receives an alarm signal from the alarm control unit 48, it issues the necessary warning using an image, light, or sound based on the alarm signal.

When the communication device 23 receives a notification signal from the notification control unit 48, it transmits the notification signal to the remote control device 60. In response to the notification signal, the remote control device 60 issues a warning by displaying an image or light on the display device 63, or by emitting a sound from a speaker or the like.

The control method for the electric working machine in this embodiment is carried out as described above.
＜Effects＞
Next, the effects of this embodiment will be described.

In the case of small electric shovels used for landscaping, water pipe work, etc., the batteries installed are also small. This means that a replacement battery can be carried on the electric shovel, and when the remaining charge of the battery in use becomes low, it can be replaced with the replacement battery.

However, in the case of medium- and large-sized electric excavators, the batteries installed are also large. This makes it difficult to transport replacement batteries on an electric excavator or truck, and the task of replacing the battery itself is also difficult.

In addition, in work sites that involve large premises, rivers, mountains, or remote areas, it is difficult to install charging equipment, so electric excavators may be used at sites far away from the charging equipment. In such cases, the electric excavator must travel back and forth between the distant charging equipment and the work site.

In addition, with electric shovels, excavation and other tasks are performed using power stored in the battery, so power is also consumed by the operation of the work equipment. For this reason, if the operator of an electric shovel does not accurately grasp the remaining charge in the battery, the battery charge may reach 0 (zero) before arriving at the charging facility or during work. Furthermore, if the operator does not accurately grasp the remaining charge in the battery, there is a risk that he or she will stop work and start moving to the charging facility even though there is still sufficient charge left in the battery, which could reduce work efficiency.

In contrast, in this embodiment, as shown in FIG. 3, the controller 40 outputs notification information when it determines that the amount of electricity required to move the distance between the charging equipment 50 and the electric shovel 100 is equal to or greater than the remaining battery charge stored in the battery 31. This makes it possible to know the exact amount of electricity required to reach the charging equipment 50.

Furthermore, according to this embodiment, as shown in FIG. 3, the controller 40 calculates the separation distance based on the position information of the charging equipment 50 that is pre-stored in the memory unit 45. This eliminates the need to obtain the position information of the charging equipment 50 through the receiver 22, and the device configuration can be simplified.

Furthermore, according to this embodiment, as shown in FIG. 3, the controller 40 refers to information indicating the relationship between the separation distance and the amount of electricity required for the electric shovel 100 to move, and calculates the required amount of electricity based on the separation distance. This makes it possible to easily calculate the required amount of electricity.

Furthermore, according to this embodiment, as shown in FIG. 3, the controller 40 calculates the required amount of electricity by taking into account at least one of the slip rate based on the soil information of the work site and the slope based on the elevation difference to the charging facility. This makes it possible to know the amount of electricity required to reach the charging facility 50 more accurately.

Furthermore, according to this embodiment, as shown in FIG. 3, the controller 40 changes the alarm output format according to the difference between the required amount of electricity and the remaining battery charge. This allows the operator to properly grasp the remaining battery charge.

Also, according to this embodiment, as shown in FIG. 3, when the controller 40 determines that the required amount of electricity is equal to or greater than the remaining charge in the storage battery, it controls the running body 5 (running motor 5M) to impose a limit on the running speed. This makes it possible to suppress unnecessary power consumption that occurs when the running speed is increased.

Furthermore, according to this embodiment, as shown in FIG. 3, when the controller 40 determines that the required amount of electricity is equal to or greater than the remaining battery charge stored in the battery, it outputs notification information to the display device 63 (notification device) via the communication device 23 to notify the display device 63. As a result, if there is a remote manager away from the electric shovel 100, that manager can recognize the status of the battery 31 in the electric shovel 100.

<Additional Notes>
The above description includes the following additional features.

(Appendix 1)
An electric powered working machine,
A battery that is charged by a charging facility;
a traveling body that travels using power supplied from the battery;
a position sensor for acquiring position information of the electric working machine;
and a controller that calculates a separation distance between the charging facility and the electric work machine based on position information of the charging facility and position information of the electric work machine acquired by the position sensor, calculates a required amount of electricity needed to move the separation distance, and outputs notification information when it determines that the required amount of electricity is equal to or greater than the remaining battery charge stored in the battery.

(Appendix 2)
Further comprising a storage unit,
The electric working machine according to claim 1, wherein the controller calculates the separation distance based on position information of the charging facility that is pre-stored in the memory unit.

(Appendix 3)
The electric working machine according to claim 1 or 2, wherein the controller calculates the required amount of electricity based on the separation distance by referring to information indicating a relationship between the separation distance and an amount of electricity required for the electric working machine to move.

(Appendix 4)
The electric work machine according to any one of Supplementary Note 1 to Supplementary Note 3, wherein the controller calculates the required amount of electricity taking into account at least one of a slip ratio based on soil information of a work site and a slope based on an elevation difference to the charging equipment.

(Appendix 5)
The electric working machine according to any one of Supplementary Note 1 to Supplementary Note 4, wherein the controller changes a form of an alarm output in accordance with a difference between the required amount of electricity and the remaining charge of the storage battery.

(Appendix 6)
The electric working machine according to any one of Supplementary Note 1 to Supplementary Note 5, wherein the controller controls the traveling body so as to impose a limit on a traveling speed when it determines that the required amount of electricity is equal to or greater than the remaining charge of the storage battery.

(Appendix 7)
An electric powered working machine,
A battery that is charged by a charging facility;
a traveling body that travels using power supplied from the battery;
a position sensor for acquiring position information of the electric working machine;
a controller that calculates a separation distance between the charging facility and the electric work machine based on position information of the charging facility and position information of the electric work machine acquired by the position sensor, calculates a required amount of electricity needed to move the separation distance, and outputs notification information when it determines that the required amount of electricity is equal to or greater than the remaining battery charge stored in the battery.

(Appendix 8)
an alarm device disposed away from the electric working machine;
A transmitter that transmits notification information to the notification device,
The control system for an electric working machine as described in Appendix 7, wherein the controller outputs the notification information via the transmitter to notify the notification device when it determines that the required amount of electricity is equal to or greater than the remaining battery charge stored in the battery.

(Appendix 9)
A control method for an electric working machine including a battery that is charged by a charging facility and a traveling body that travels using electric power supplied from the battery, comprising:
calculating a separation distance between the charging facility and the electric working machine based on position information of the charging facility and position information of the electric working machine;
Calculating the amount of electricity required to move the separation distance;
and outputting notification information when it is determined that the required amount of electricity is equal to or greater than a remaining battery charge stored in the battery.

The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims.

1 Main body, 2 Work equipment, 3 Swivel body, 4 Cab, 4S Cab, 5 Running body, 5Cr Track, 5M Running motor, 6 Boom, 7 Arm, 8 Bucket, 9 Exterior cover, 10 Boom cylinder, 11 Arm cylinder, 12 Bucket cylinder, 13 Boom foot pin, 14 Boom top pin, 15 Arm top pin, 17 Bucket link, 21, 51 Position sensor, 21a, 21b GNSS receiver, 22 Receiver, 23 Communication device, 24 Surrounding information sensor, 25 Notification device, 26, 62 Operation device, 31 Back 32 remaining charge sensor, 33 inverter, 34 electric motor, 35 hydraulic pump, 36 electromagnetic control valve for work equipment, 37 electromagnetic control valve for travel motor, 40 controller, 41 work equipment position acquisition unit, 42 charging equipment position acquisition unit, 43 remaining charge acquisition unit, 44 distance calculation unit, 45, 52 memory unit, 46 required electricity amount calculation unit, 47 movement possibility determination unit, 48 notification control unit, 50 charging equipment, 53 transmission device, 60 remote control device, 61 communication device, 63 display device, 100 electric shovel, RX rotation axis, TA hydraulic oil tank.

Claims (9)

An electric powered working machine,
A battery that is charged by a charging facility;
a traveling body that travels using power supplied from the battery;
a position sensor for acquiring position information of the electric working machine;
and a controller that calculates a separation distance between the charging facility and the electric work machine based on position information of the charging facility and position information of the electric work machine acquired by the position sensor, calculates a required amount of electricity needed to move the separation distance, and outputs notification information when it determines that the required amount of electricity is equal to or greater than the remaining battery charge stored in the battery. Further comprising a storage unit,
The electric operating machine according to claim 1 , wherein the controller calculates the separation distance based on position information of the charging facility that is pre-stored in the storage unit. The electric work machine according to claim 1, wherein the controller calculates the required amount of electricity based on the distance by referring to information indicating the relationship between the distance and the amount of electricity required for the electric work machine to move. The electric work machine according to claim 1, wherein the controller calculates the required amount of electricity by taking into account at least one of a slip ratio based on soil information of the work site and a slope based on the difference in elevation to the charging facility. The electric work machine according to claim 1, wherein the controller changes the alarm output form according to the difference between the required amount of electricity and the remaining charge of the storage battery. The electric work machine according to claim 1, wherein the controller controls the vehicle to impose a limit on the travel speed when it is determined that the required amount of electricity is equal to or greater than the remaining charge in the storage battery. An electric powered working machine,
A battery that is charged by a charging facility;
a traveling body that travels using power supplied from the battery;
a position sensor for acquiring position information of the electric working machine;
a controller that calculates a separation distance between the charging facility and the electric work machine based on position information of the charging facility and position information of the electric work machine acquired by the position sensor, calculates a required amount of electricity needed to move the separation distance, and outputs notification information when it determines that the required amount of electricity is equal to or greater than the remaining battery charge stored in the battery. an alarm device disposed away from the electric working machine;
A transmitter that transmits notification information to the notification device,
8. The control system for an electric working machine according to claim 7, wherein the controller outputs the notification information to the notification device via the transmitter when it determines that the required amount of electricity is equal to or greater than the remaining battery charge stored in the battery. A control method for an electric working machine including a battery that is charged by a charging facility and a traveling body that travels using electric power supplied from the battery, comprising:
calculating a separation distance between the charging facility and the electric working machine based on position information of the charging facility and position information of the electric working machine;
Calculating the amount of electricity required to move the separation distance;
and outputting notification information when it is determined that the required amount of electricity is equal to or greater than a remaining battery charge stored in the battery.

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