Shovel

Abstract

To improve safety when de-icing a glass surface of a shovel.SOLUTION: A shovel, which is driven by a hydraulic pump, has a cab for operating the shovel, an electric motor for driving the hydraulic pump, a battery for supplying power to the electric motor, and a control unit for controlling an operation of the shovel. The control unit has an ice-melting mode that warms the glass surface of the cab when the electric motor is not operating.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a shovel. [Background technology]

[0002] BACKGROUND ART It is known that in an electric excavator, the heat of heated hydraulic oil is used to warm the inside of the operator's cab (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-0236871 Summary of the Invention [Problem to be solved by the invention]

[0004] In an electric shovel, the electric motor is operated to warm up the hydraulic oil, and therefore, in order to warm the inside of the operator's cab using the heat of the warmed hydraulic oil in the electric shovel, it is necessary to operate the electric motor.

[0005] Incidentally, in areas with heavy snowfall or cold climates, if snow or ice accumulates on the glass surface of a shovel, it becomes difficult to work with the shovel. In particular, when snow or ice accumulates on the glass surface of a shovel, visibility is reduced, increasing the danger of work. Furthermore, when a shovel operator attempts to get on the shovel, snow or ice adhering to the glass surface may hinder the operator's access. Therefore, it is preferable to remove snow or ice adhering to the glass surface by, for example, melting it before work begins.

[0006] When removing snow or ice from the windshield, the electric motor is operated and the heat of the warmed hydraulic oil is used to warm the windshield and the driver's cab. Therefore, when defrosting and removing snow or ice from the windshield before work, operating the electric motor while the excavator is unmanned means that the hydraulic pump that drives the excavator's attachments will be operating unmanned, which raises safety concerns.

[0007] Therefore, there is a need to improve safety when de-icing glass surfaces in excavators that operate by driving a hydraulic pump with an electric motor. [Means for solving the problem]

[0008] In order to achieve the above object, the present disclosure: A shovel operated by driving a hydraulic pump, a driver's cab for operating the shovel; an electric motor that drives the hydraulic pump; a battery that supplies power to the electric motor; a control unit that controls the drive of the shovel, The control unit has an ice-thawing mode for warming the glass surface of the driver's cab while the electric motor is not operating. [Effects of the Invention]

[0009] According to the present disclosure, safety can be improved when de-icing glass surfaces in an excavator that operates by driving a hydraulic pump with an electric motor. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a side view showing a shovel according to an embodiment. FIG. [Figure 2] FIG. 1 is a block diagram illustrating an example of a configuration of a shovel according to an embodiment of the present invention. [Figure 3] FIG. 2 is a schematic diagram of a power supply system and an air conditioning system mounted on the shovel according to the present embodiment. [Figure 4] 10 is a flowchart for explaining the operation of the shovel according to the present embodiment when an ice-melting mode is executed. [Figure 5] FIG. 1 is a diagram illustrating an example of a system in which a shovel is remotely controlled. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments described below are examples and do not limit the invention, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention. Note that the same or corresponding components in each drawing are denoted by the same or corresponding reference numerals, and descriptions thereof may be omitted.

[0012] First, an outline of a shovel according to an embodiment will be described.

[0013] [Outline of the Excavator] FIG. 1 is a side view showing a shovel according to an embodiment.

[0014] As shown in Figure 1, the excavator 200 of this embodiment comprises a lower running body 1, an upper rotating body 3 mounted on the lower running body 1 so as to be rotatable via a rotating mechanism 2, a boom 4, an arm 5, and a bucket 6 as attachments, and a cabin 10.

[0015] The lower traveling body 1 includes, for example, a pair of left and right crawlers, and is self-propelled by the crawlers being hydraulically driven by traveling hydraulic motors 1R, 1L (see FIG. 2).

[0016] The upper swing body 3 swings relative to the undercarriage 1 by being hydraulically driven by a swing hydraulic motor 2M (see FIG. 2) through the swing mechanism 2. All driven elements (for example, the swing hydraulic motor 2M) are hydraulically driven by hydraulic oil supplied from a main pump 14 (see FIG. 2). This corresponds to a configuration in which the power source (engine) of a so-called hydraulic excavator is replaced with a pump electric motor 12. In this way, the excavator 200 in this embodiment operates by driving the main pump 14, which is an example of a hydraulic pump, by the pump electric motor 12, which is an example of an electric motor.

[0017] Furthermore, the upper rotating body 3 may be electrically driven by a rotating electric motor driven by power supplied from a battery module 19 (see FIG. 2) through the rotating mechanism 2, instead of the rotating hydraulic motor 2M. In this case, for example, the excavator 200 is connected to the rotating electric motor from the battery module 19 via a power conversion device 100 (see FIG. 2) and an inverter. The rotating electric motor may perform a power running operation to drive the upper rotating body 3 to rotate, and a regenerative operation to generate regenerative power to brake the upper rotating body 3 while rotating, under the control of the excavator controller 30 and the inverter. Furthermore, the rotating electric motor may supply regenerative power to the battery module 19 or the pump electric motor 12 (see FIG. 2) via an inverter.

[0018] A boom 4 is attached to the front center of the upper rotating body 3 so as to be able to tilt up and down, an arm 5 is attached to the tip of the boom 4 so as to be able to rotate up and down, and a bucket 6 is attached to the tip of the arm 5 so as to be able to rotate up and down. The boom 4, arm 5, and bucket 6 are hydraulically driven by a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9, which serve as hydraulic actuators, respectively.

[0019] The bucket 6 is an example of an end attachment, and other end attachments may be attached to the tip of the arm 5 instead of the bucket 6 depending on the type of work, etc. The other end attachments may be buckets of a different type from the bucket 6, such as a slope bucket or a dredging bucket. The other end attachments may also be end attachments of a different type from the bucket, such as a breaker, a mixer, a grapple, etc.

[0020] The cabin 10 is an example of a driver's cab for operating the excavator 200. The cabin 10 is mounted on the front left side of the upper rotating body 3, and inside (inside) it is provided with a driver's seat where an operator sits, an operating device 26 (see FIG. 2) described later, and the like.

[0021] In response to operations by an operator seated in a cabin 10, the excavator 200 operates driven elements such as a lower traveling body 1 (left and right crawlers), an upper rotating body 3, a boom 4, an arm 5, and a bucket 6.

[0022] The excavator 200 may automatically operate the actuators regardless of the operation by the operator. This allows the excavator 200 to realize a function (so-called "automatic driving function" or "machine control function") that automatically operates at least some of the driven elements such as the lower traveling structure 1 (crawlers 1CL, 1CR), upper rotating structure 3, boom 4, arm 5, and bucket 6.

[0023] The automatic driving function may include a function (so-called "semi-automatic driving function") that automatically operates driven elements (actuators) other than the driven element (hydraulic actuator) to be operated in response to an operator's operation of the operating device 26 or remote control, which will be described later. The automatic driving function may also include a function (so-called "fully automatic driving function") that automatically operates at least some of the multiple driven elements (actuators) on the assumption that there is no operation of the operating device 26 by the operator or remote control. In the shovel 200, when the fully automatic driving function is enabled, the inside of the cabin 10 may be unmanned. The semi-automatic driving function, the fully automatic driving function, etc. may also include a mode in which the operation content of the driven element (actuator) to be operated automatically is determined according to predetermined rules. The semi-automatic driving function, the fully automatic driving function, etc. may also include a mode in which the shovel 200 autonomously makes various decisions and autonomously determines the operation content of the driven element (actuator) to be operated automatically in accordance with the decision results (so-called "autonomous driving function").

[0024] [Excavator configuration] Next, the configuration of a shovel 200 according to this embodiment will be described with reference to FIG. 2 in addition to FIG.

[0025] Fig. 2 is a block diagram showing an example of the configuration of a shovel 200 according to this embodiment. In Fig. 2, mechanical power lines are indicated by double lines, hydraulic lines by thick solid lines, pilot lines by dashed lines, and electric drive and control lines by thin solid lines.

[0026] <Hydraulic drive system> The hydraulic drive system of the excavator 200 according to this embodiment includes hydraulic actuators such as traveling hydraulic motors 1R, 1L, swing hydraulic motor 2M, boom cylinder 7, arm cylinder 8, and bucket cylinder 9, which hydraulically drive each of the driven elements such as the lower traveling structure 1, boom 4, arm 5, and bucket 6. The hydraulic drive system of the excavator 200 according to this embodiment also includes a pump electric motor 12, a main pump 14, and a control valve 17.

[0027] The pump electric motor 12 is a power source for the hydraulic drive system. The pump electric motor 12 is, for example, an IPM (Interior Permanent Magnet) motor. The pump electric motor 12 is connected to a high-voltage power supply including a battery module 19 and a power conversion device 100 via an inverter 18A. The pump electric motor 12 is powered by three-phase AC power supplied from the battery module 19 via the inverter 18A, and drives the main pump 14 and the pilot pump 15. Drive control of the pump electric motor 12 may be performed by the inverter 18A under the control of a shovel controller 30, which will be described later.

[0028] The main pump 14 draws hydraulic oil from a hydraulic oil tank T and discharges it into a high-pressure hydraulic line 16, thereby supplying the hydraulic oil to a control valve 17 through the high-pressure hydraulic line 16. The main pump 14 is driven by a pump electric motor 12. The main pump 14 is, for example, a variable displacement hydraulic pump, and a regulator (not shown) controls the angle (tilting angle) of the swash plate under the control of an excavator controller 30 (described later). This allows the main pump 14 to adjust the stroke length of the piston and thereby adjust the discharge flow rate (discharge pressure).

[0029] The main pump 14 may be driven by power from another power source in addition to the pump electric motor 12. For example, the main pump 14 may be driven by regenerating energy of hydraulic oil discharged from the boom cylinder 7 or arm cylinder 8 to a hydraulic oil tank due to the weight of the boom 4 or arm 5 when the boom 4 is lowered or the arm 5 is closed. Specifically, a hydraulic motor disposed coaxially with the rotation shaft of the main pump 14 may be driven by the energy of hydraulic oil discharged from the boom cylinder 7 or arm cylinder 8 to a hydraulic oil tank due to the weight of the boom 4 or arm 5 when the boom 4 is lowered or the arm 5 is closed. Furthermore, the energy of hydraulic oil discharged from the boom cylinder 7 or arm cylinder 8 to a hydraulic oil tank due to the weight of the boom 4 or arm 5 when the boom 4 is lowered or the arm 5 is closed may be regenerated to cause a generator to generate electricity. Specifically, the hydraulic motor arranged coaxially with the generator may be driven by the energy of hydraulic oil discharged from the boom cylinder 7 or the arm cylinder 8 into the hydraulic oil tank due to the weight of the boom 4 or the arm 5 when the boom 4 is lowered or the arm 5 is closed, thereby causing the generator to generate electricity. In this case, the generated power of the generator may be supplied to the pump motor 12 or may be used to charge the battery module 19.

[0030] The control valve 17 is a hydraulic control device that controls the hydraulic drive system in response to an operation command corresponding to an operator's operation or an automatic driving function. As described above, the control valve 17 is connected to the main pump 14 via the high-pressure hydraulic line 16, and is configured to be able to selectively supply hydraulic oil supplied from the main pump 14 to the hydraulic actuators (travel hydraulic motors 1R, 1L, swing hydraulic motor 2M, boom cylinder 7, arm cylinder 8, and bucket cylinder 9). For example, the control valve 17 is a valve unit including a plurality of control valves (directional switching valves) that control the flow rate and flow direction of hydraulic oil supplied from the main pump 14 to each of the hydraulic actuators. The hydraulic oil supplied from the main pump 14 and flowing through the control valve 17 and the hydraulic actuators is discharged from the control valve 17 to the hydraulic oil tank T.

[0031] <Electric drivetrain> The electric drive system of the shovel 200 according to this embodiment includes the pump motor 12, the sensor 12s, and the inverter 18A. The electric drive system of the shovel 200 according to this embodiment also includes a high-voltage power supply configured by a battery module 19, a power conversion device 100, etc.

[0032] The sensors 12s include a current sensor 12s1, a voltage sensor 12s2, and a rotation state sensor 12s3.

[0033] The current sensor 12s1 detects the current of each of the three phases (U phase, V phase, and W phase) of the pump motor 12. The current sensor 12s1 is provided, for example, on a power path between the pump motor 12 and the inverter 18A. Detection signals corresponding to the current of each of the three phases of the pump motor 12 detected by the current sensor 12s1 are directly input to the inverter 18A via a communication line. The detection signals may also be input to the shovel controller 30 via the communication line and input to the inverter 18A via the shovel controller 30.

[0034] The voltage sensor 12s2 detects the voltages applied to each of the three phases of the pump motor 12. The voltage sensor 12s2 is provided, for example, on a power path between the pump motor 12 and the inverter 18A. Detection signals corresponding to the voltages applied to each of the three phases of the pump motor 12 detected by the voltage sensor 12s2 are directly input to the inverter 18A via a communication line. The detection signals may also be input to the shovel controller 30 via the communication line and input to the inverter 18A via the shovel controller 30.

[0035] The rotation state sensor 12s3 detects the rotation state (for example, the rotation position (rotation angle), the rotation speed, etc.) of the pump motor 12. The rotation state sensor 12s3 is, for example, a rotary encoder or a resolver.

[0036] The inverter 18A drives and controls the pump motor 12 under the control of the shovel controller 30. The inverter 18A includes, for example, a conversion circuit that converts DC power into three-phase AC power and converts three-phase AC power into DC power, a drive circuit that switches and drives the conversion circuit, and a control circuit that outputs a control signal (for example, a PWM (Pulse Width Modulation) signal) that defines the operation of the drive circuit.

[0037] The control circuit of the inverter 18A controls the drive of the pump motor 12 while grasping the operating state of the pump motor 12. For example, the control circuit of the inverter 18A grasps the operating state of the pump motor 12 based on the detection signal of the rotation state sensor 12s3. Alternatively, the control circuit of the inverter 18A may grasp the operating state of the pump motor 12 by successively estimating the rotation angle of the rotating shaft of the pump motor 12, etc., based on the detection signal of the current sensor 12s1 and the detection signal of the voltage sensor 12s2 (or a voltage command value generated in the control process).

[0038] At least one of the drive circuit and the control circuit of the inverter 18A may be provided outside the inverter 18A.

[0039] The battery module 19 is configured to supply the charged power to electronic components within the shovel 200.

[0040] The power conversion device 100 boosts the power of the battery module 19, or reduces the power from the pump motor 12 via the inverter 18A and stores the power in the battery module 19. The power conversion device 100 switches between a boost operation and a step-down operation depending on the operating state of the pump motor 12 so that the voltage value of a DC (Direct Current) bus 110 falls within a certain range. The control for switching between the boost operation and the step-down operation of the power conversion device 100 may be executed by the shovel controller 30 based on, for example, the detected voltage value of the DC bus 110, the detected voltage value of the battery module 19, and the detected current value of the battery module 19.

[0041] If there is no need to boost the output voltage of the battery module 19 and apply it to the pump motor 12, the power conversion device 100 may be omitted.

[0042] <Operation system> The operating system of the shovel 200 according to this embodiment includes a pilot pump 15, an operating device 26, and a pressure control valve 31.

[0043] The pilot pump 15 supplies pilot pressure to various hydraulic devices (e.g., pressure control valve 31) mounted on the shovel 200 via a pilot line 25. As a result, the pressure control valve 31 can supply pilot pressure to the control valve 17 according to the operation content (e.g., operation amount and operation direction) of the operating device 26 under the control of the shovel controller 30. Therefore, the shovel controller 30 and the pressure control valve 31 can realize the operation of the driven element (hydraulic actuator) according to the operation content of the operating device 26 by the operator. Furthermore, under the control of the shovel controller 30, the pressure control valve 31 can supply pilot pressure to the control valve 17 according to the remote operation content specified by the remote operation signal. The pilot pump 15 is, for example, a fixed displacement hydraulic pump, and is driven by the pump electric motor 12 as described above.

[0044] The operation device 26 is provided within reach of the operator in the driver's seat of the cabin 10 and is used by the operator to operate each driven element (i.e., the left and right crawlers of the undercarriage 1, the upper revolving body 3, the boom 4, the arm 5, the bucket 6, etc.). In other words, the operation device 26 is used by the operator to operate hydraulic actuators (e.g., the traveling hydraulic motors 1R and 1L, the swing hydraulic motor 2M, the boom cylinder 7, the arm cylinder 8, the bucket cylinder 9, etc.) and electric actuators that drive each driven element. The operation device 26 is, for example, electric, and outputs an electric signal (hereinafter referred to as an "operation signal") corresponding to the operation content by the operator. The operation signal output from the operation device 26 is input to the excavator controller 30 via a signal line 28. In this way, the excavator controller 30 can control the pressure control valve 31 and control the operation of the driven elements (actuators) of the excavator 200 in accordance with the operation content of the operator and operation commands corresponding to the automatic driving function.

[0045] The operation device 26 includes, for example, levers 26A to 26C. The lever 26A may be configured to be able to receive operations related to the arm 5 (arm cylinder 8) and the upper rotating body 3 (swing operation) in accordance with operations in the front-rear direction and the left-right direction. The lever 26B may be configured to be able to receive operations related to the boom 4 (boom cylinder 7) and the bucket 6 (bucket cylinder 9) in accordance with operations in the front-rear direction and the left-right direction. The lever 26C may be configured to be able to receive operations related to the lower traveling body 1 (crawler), for example.

[0046] In addition, when the control valve 17 is configured as an electromagnetic pilot type control valve (directional control valve), an operation signal from the electric operating device 26 may be input directly to the control valve 17, and each hydraulic control valve may perform an operation according to the operation content of the operating device 26. Also, the operating device 26 may be of a hydraulic pilot type that outputs a pilot pressure according to the operation content. In this case, the pilot pressure according to the operation content is supplied to the control valve 17.

[0047] The pressure control valve 31 outputs a predetermined pilot pressure using hydraulic oil supplied from the pilot pump 15 through the pilot line 25 under the control of the excavator controller 30. The pilot line on the secondary side of the pressure control valve 31 is connected to the control valve 17, and the pilot pressure output from the pressure control valve 31 is supplied to the control valve 17.

[0048] <Power system> The shovel 200 includes, as components for charging the battery module 19, a normal charging vehicle inlet 101 and a rapid charging vehicle inlet 102.

[0049] Normal charging vehicle inlet 101 is configured to be connectable to a charging connector provided at the tip of a predetermined cable (hereinafter referred to as a "charging cable") of an external power source.

[0050] The charging AC-DC converter 103 converts AC power supplied from an external power source via the normal charging vehicle inlet 101 into DC power that can be charged into the battery 192 and supplies it to the battery module 19.

[0051] The quick-charging vehicle inlet 102 is configured to be connectable to a charging connector provided at the tip of a charging cable of an external power source (e.g., a charging station). The quick-charging vehicle inlet 102 is an inlet for performing quick charging based on, for example, CHAdeMO (registered trademark). In this embodiment, by using such a DC charging method, DC power can be supplied to the battery module 19 without going through an AC-DC converter.

[0052] The battery module 19 of the shovel 200 according to this embodiment supplies power to each component within the shovel 200. The battery module 19 includes a battery 192 and a battery controller 191.

[0053] The battery 192 supplies power to various components within the shovel 200. For example, the battery 192 supplies charged (stored) power to the pump motor 12. The battery 192 also stores power generated by the pump motor 12 (regenerated power).

[0054] The battery 192 is charged (stores electricity) by being connected to an external power source via a charging cable.

[0055] The battery 192 is, for example, a lithium ion battery, and has a relatively high output voltage (for example, several hundred volts).

[0056] The battery controller 191 controls the internal configuration of the battery module 19. For example, the battery controller 191 calculates the SOC (State Of Charge) of the battery 192. Then, the battery controller 191 outputs the SOC to the shovel controller 30. This enables the shovel controller 30 to display the SOC of the battery 192 on the output device 50 (display device) inside the cabin 10.

[0057] The battery controller 191 determines whether power supply is possible based on whether a connection to an external power source is made via a charging cable via the normal charging vehicle inlet 101 or the quick charging vehicle inlet 102. In this embodiment, whether power supply is possible is determined based on whether a charging cable is connected between the external power source and the shovel 200. Note that this embodiment does not limit the method for determining whether power supply is possible to a determination based on whether a charging cable is connected. For example, when wireless power supply is performed, other methods may be used, such as determining whether power supply is possible through mutual communication with charging equipment provided with an external power source.

[0058] <Control system> The control system of the shovel 200 according to this embodiment includes a shovel controller 30, an output device 50, and an input device 52.

[0059] The output device 50 is provided in the cabin 10, and outputs various types of information to the operator under the control of the shovel controller 30. The output device 50 includes, for example, a display device that outputs (notifies) information to the operator in a visual manner. The display device may be installed, for example, in a location that is easily visible to the operator in the cabin 10, and may display various information images under the control of the shovel controller 30. The display device is, for example, a liquid crystal display or an organic EL (Electroluminescence) display. The output device 50 also includes, for example, a sound output device that outputs information to the operator in an auditory manner. The sound output device is, for example, a buzzer, a speaker, etc.

[0060] The input device 52 is provided in the cabin 10 and accepts various inputs from the operator. The input device 52 may include, for example, an operation input device that accepts operation inputs from the operator. The operation input device includes, for example, a button, a toggle, a lever, a touch panel, a touchpad, etc. The input device 52 may also include, for example, a voice input device that accepts voice inputs from the operator and a gesture input device that accepts gesture inputs from the operator. The voice input device includes, for example, a microphone that captures the voice of the operator in the cabin 10. The gesture input device includes, for example, an indoor camera that can capture images of the operator's gestures in the cabin 10. A signal corresponding to the input from the operator accepted by the input device 52 is taken into the excavator controller 30.

[0061] The shovel controller 30 is one example of a control unit in the present invention, and each function may be realized by any hardware or any combination of hardware and software, etc. For example, the shovel controller 30 may be configured mainly with a computer including a processor such as a CPU (Central Processing Unit), a memory device (main storage device) such as a RAM (Random Access Memory), a non-volatile auxiliary storage device such as a ROM (Read Only Memory), and an interface device for input / output with the outside.

[0062] The shovel controller 30 controls the drive of the shovel 200. For example, the shovel controller 30 outputs a control command to the pressure control valve 31 in response to an operation signal input from the operating device 26, and causes the pressure control valve 31 to output a pilot pressure corresponding to the operation content of the operating device 26. In this way, the shovel controller 30 can realize the operation of the driven element (hydraulic actuator) of the shovel 200 corresponding to the operation content of the electric operating device 26.

[0063] The shovel controller 30 may perform control related to, for example, an automatic driving function. Specifically, the shovel controller 30 may output a control command to the pressure control valve 31 and cause the pressure control valve 31 to apply a pilot pressure corresponding to an operation command corresponding to the automatic driving function to the control valve 17. In this way, the shovel controller 30 can realize the operation of the driven element (hydraulic actuator) of the shovel 200 corresponding to the automatic driving function.

[0064] The shovel controller 30 may comprehensively control the operation of the entire shovel 200 (various devices mounted on the shovel 200).

[0065] The shovel controller 30 performs drive control of the electric drive system based on various input information (for example, control commands including operation signals from the operation device 26, etc.).

[0066] Furthermore, the shovel controller 30 may, for example, drive the power conversion device 100 based on the operation state of the operation device 26, and perform switching control between step-up operation and step-down operation of the power conversion device 100, in other words, between the discharge state and the charge state of the battery module 19. Furthermore, for example, when the automatic operation function of the shovel 200 is enabled, the shovel controller 30 may drive the power conversion device 100 based on an operation command corresponding to the automatic operation function, and perform switching control between the discharge state and the charge state of the battery module 19.

[0067] The shovel controller 30 may control an air conditioning system 90 (see FIG. 3 ) of the shovel 200, which will be described later. Furthermore, as part of the control of the air conditioning system 90, the shovel controller 30 may control the operation and stopping of an HVAC (Heating, Ventilation, and Air Conditioning) 91, a water pump 92, and a water heater 93. The HVAC 91, the water pump 92, and the water heater 93 will be described later. The shovel controller 30 is equipped with a melting mode that performs the operation described later using the air conditioning system 90.

[0068] <Excavator air conditioning system configuration> 3 is a schematic diagram of a power supply system and an air conditioning system mounted on the shovel 200 according to this embodiment. The power cable is indicated by a double line, the refrigerant flow path is indicated by a thick solid line, and the signal line is indicated by a dotted line.

[0069] In the example shown in Fig. 3, the rapid charging vehicle inlet 102 provided on the excavator 200 is connected to the charging station 1301 via a charging cable 1311 so that power can be supplied from the charging station 1301. Note that this embodiment describes an example in which the rapid charging vehicle inlet 102 is connected to the charging station 1301 so that rapid charging can be performed. However, this embodiment does not limit the inlet or the like to be connected as long as the battery 192 can receive power from an external power source (for example, the charging station 1301). For example, the charging station 1301 may be connected to the normal charging vehicle inlet 101.

[0070] The air conditioning system 90 of this embodiment includes an HVAC 91 , a water pump 92 , a water heater 93 , a reserve tank 94 , and a water circulation passage 96 .

[0071] The water circulation flow path 96 is a path for circulating water among the water pump 92, the water heater 93, the reserve tank 94, and the HVAC 91. Note that, although this embodiment will be described as an example of circulating water, the circulation is not limited to water circulation, and any liquid circulation may be used.

[0072] The water pump 92 circulates the water within the water circulation flow path 96 by sucking in and discharging water flowing from the water circulation flow path 96 under the control of the shovel controller 30 .

[0073] The HVAC 91 is configured to be able to adjust the state of air inside the cabin 10 under control of the excavator controller 30. The state of air refers to, for example, temperature or humidity. The HVAC 91 according to this embodiment is an apparatus unit that integrally includes devices for adjusting the state of air, such as a blower, a heat exchanger, and a humidifier. For example, the HVAC 91 adjusts the temperature of the air inside the cabin 10 by exchanging heat between water flowing through a water circulation flow path 96 and the air inside the cabin 10.

[0074] The water heater 93 heats the water flowing through the water circulation flow path 96 under control of the shovel controller 30. The water heater 93 may be any heater capable of heating water. For example, a PTC heater may be used.

[0075] The reserve tank 94 is a tank provided to temporarily store water flowing through the water circulation flow path 96. For example, even if the temperature of the water changes due to heating by the water heater 93 or the like and the volume of the water flowing through the water circulation flow path 96 changes, the reserve tank 94 can temporarily store water, so the internal pressure within the water circulation flow path 96 can be adjusted and the load on the water circulation flow path 96 can be reduced.

[0076] <Excavator controller function blocks> Each functional block in the shovel controller 30 will be described. Each functional block in the shovel controller 30 is conceptual and does not necessarily have to be physically configured as shown in the figure. All or part of each functional block can be configured by functionally or physically distributing or integrating it in any unit. All or any part of the processing functions performed by each functional block are realized by a program executed by a CPU. Alternatively, each functional block may be realized as hardware using wired logic.

[0077] In this embodiment, the shovel controller 30 controls charging of the battery 192 when the shovel controller 30 is connected via a charging cable 1311 between a charging station (an example of an external power source) 1301 and either a normal charging vehicle inlet 101 or a quick charging vehicle inlet 102 so that the battery can be charged. In addition, in the thawing mode, the shovel controller 30 controls each component of the air conditioning system 90 while the pump motor 12 is not operating to warm the glass surface of the cabin 10.

[0078] For this reason, the shovel controller 30 includes an acquisition unit 301, a determination unit 302, a heating control unit 303, and a charging control unit 304. Furthermore, the shovel controller 30 includes a set time holding unit 305 in the non-volatile auxiliary storage device.

[0079] The set time holding unit 305 holds time information indicating the work start time at which the shovel 200 starts work. The time information for the work start time held by the set time holding unit 305 may be time information input by an operator aboard the shovel 200 via the input device 52 or time information transmitted by the operator from an external device. As another example, the set time holding unit 305 may hold time information indicating the work start time for each schedule, which is automatically set in accordance with work schedule information created in advance by a management center (an example of a management device) that manages the work site. Furthermore, the auxiliary storage device may store work history information including the past work start and end times of the shovel 200, the shovel controller 30 may estimate the work start time for each schedule based on the work history information, and the set time holding unit 305 may store the time information for the estimated work start time for each schedule. In this way, any setting method, including well-known methods, may be used to set the time information held by the set time holding unit 305.

[0080] The acquisition unit 301 acquires signals from various components within the shovel 200. For example, the acquisition unit 301 acquires information indicating whether or not the shovel 200 is connected to an external power source (for example, the charging station 1301) from the battery controller 191. Furthermore, when the shovel 200 is connected to an external power source (for example, the charging station 1301), the acquisition unit 301 may acquire information (for example, the maximum power that can be supplied) about the connected external power source (for example, the charging station 1301) from the battery controller 191.

[0081] The acquisition unit 301 also acquires the SOC of the battery 192 output from the battery controller 191.

[0082] The acquisition unit 301 also acquires the detection results of the snow accumulation sensor S1 and the open / close sensor S2, and information received via the communication device T1.

[0083] The snow sensor S1 is an example of a detection means in the present invention, and is attached to the glass surface of the cabin 10 to detect snow accumulation (whether snow or ice is attached) on the glass surface. The open / close sensor S2 is attached to the door of the cabin 10 to detect whether the door of the cabin 10 is open or closed. The communication device T1 is attached to, for example, the roof of the cabin 10, and is capable of acquiring information by receiving public radio waves, etc.

[0084] The determining unit 302 determines whether to charge the battery 192 or start or end the ice-thawing mode using the air conditioning system 90 based on the information acquired by the acquiring unit 301 .

[0085] The heating control unit 303 controls each component of the air conditioning system 90 according to the determination result by the determination unit 302, and heats the interior of the cabin 10, thereby warming the glass surface of the cabin 10. Specifically, as heating control, the heating control unit 303 starts driving the water pump 92 and controls the water heater 93 to start heating.

[0086] The charging control unit 304 controls charging of the battery 192 with power supplied from an external power source (for example, a charging station 1301) according to the determination result by the determination unit 302. For example, when the determination unit 302 determines that the charging station 1301 is connected to the battery 192 so that the battery 192 can be charged, charging of the battery 192 starts at a time according to the time information stored in the set time storage unit 305 and the SOC of the battery 192 acquired by the acquisition unit 301. The set time storage unit 305 stores the time at which the shovel 200 is to be started in order to perform work using the shovel 200.

[0087] [Thawing mode operation] As described above, in the excavator 200, if snow or ice adheres to the glass surface of the cabin 10, reducing visibility and increasing the risk of work, it is preferable to remove the snow and ice that has adhered to the glass surface. At that time, since there is a high possibility that the bucket 6 will operate high up during work using the excavator 200, it is preferable to also remove snow and ice that has adhered near the upper edge of the glass surface. However, since the glass surface of the cabin 10 has a long shape in the vertical direction and its upper edge is located at a high position, it is extremely difficult to remove snow and ice that has adhered near the upper edge of the glass surface by manual snow removal work.

[0088] Therefore, in the shovel 200 of this embodiment, the shovel controller 30 has a thawing mode in which the air conditioning system 90 is used to warm the glass surface of the cabin 10. The operation when the thawing mode is executed will be described below.

[0089] FIG. 4 is a flowchart for explaining the operation of the excavator according to this embodiment when the ice-melting mode is executed.

[0090] For example, when the charging cable 1311 is connected to the rapid charging vehicle inlet 102 in order to charge the battery 192, the battery controller 191 determines this. Then, the acquisition unit 301 acquires information that the charging cable 1311 has been connected to the rapid charging vehicle inlet 102 (YES in step ST11). At this time, the acquisition unit 301 may acquire the SOC of the battery 192 from the battery controller 191. Note that, in order to operate the shovel 200 for a full day after operating it for a full day the next day, it is usually preferable to charge the battery 192 after operating the shovel 200 for a full day. Therefore, after operating the shovel 200 for a day, the charging cable 1311 is connected to the rapid charging vehicle inlet 102. Alternatively, the normal charging vehicle inlet 101 may be connected to an external power supply depending on the time until the next time the shovel 200 is operated and the SOC of the battery 192.

[0091] Then, the determination unit 302 determines whether to start charging the battery 192 with power supplied from the charging station 1301, which is an external power source (step ST12). The determination unit 302 determines whether to start charging the battery 192 based on the time information stored in the set time storage unit 305 and the SOC of the battery 192 acquired by the acquisition unit 301. For example, if the time required to complete charging the battery 192 is eight hours based on the SOC of the battery 192 acquired by the acquisition unit 301, the determination unit 302 determines whether the current time is eight hours before the next startup time of the shovel 200, which is indicated by the time information of the shovel 200 stored in the set time storage unit 305.

[0092] If determination unit 302 determines that charging of battery 192 should be started (YES in step ST12), charging control unit 304 starts control to charge battery 192 with power supplied from charging station 1301 (step ST13). When charging battery 192 by connecting normal charging vehicle inlet 101 to an external power supply, AC power supplied from the external power supply via normal charging vehicle inlet 101 is converted by charging AC-DC converter 103 into DC power that can be charged into battery 192, and is supplied to battery module 19.

[0093] Thereafter, the determination unit 302 determines whether charging of the battery 192 is complete based on the SOC of the battery 192 transmitted from the battery controller 191 and acquired by the acquisition unit 301 (step ST14). In this embodiment, charging of the battery 192 is completed when the SOC of the battery 192 reaches 100%. In this embodiment, charging of the battery 192 is not limited to being completed when the SOC reaches 100%, and other states may also be considered. For example, the SOC may reach a predetermined reference value between 80% and 100% in consideration of the lifespan of the battery 192, or may be completed when a charging condition set by the user is satisfied.

[0094] Then, if the determination unit 302 determines that charging of the battery 192 is completed (YES in step ST14), the charging control unit 304 ends the control of charging the battery 192 with the power supplied from the charging station 1301 (step ST15).

[0095] Here, the acquisition unit 301 acquires, as weather information, a detection result indicating whether snow or ice is attached to the glass surface of the cabin 10 from the snow accretion sensor S1 attached to the glass surface of the cabin 10. If the detection result acquired by the acquisition unit 301 from the snow accretion sensor S1 indicates that snow or ice is attached to the glass surface of the cabin 10 (YES in step ST16), the determination unit 302 determines to execute the ice-thawing mode (step ST17).

[0096] In the ice-thawing mode, first, the heating control unit 303 starts driving the water pump 92 and controls the water heater 93 to start heating. When the water pump 92 starts driving, the water pump 92 sucks in and discharges water flowing from the water circulation flow path 96, thereby circulating the water within the water circulation flow path 96. The water circulating within the water circulation flow path 96 is then heated by the water heater 93. The water is heated by the water heater 93 using power supplied to the water heater 93 from the charging station 1301, which serves as an external power source.

[0097] The water heated by the water heater 93 is supplied to the HVAC 91 via a reserve tank 94 .

[0098] As described above, the HVAC 91 is an apparatus unit that integrally includes devices for adjusting the air condition, such as a blower, a heat exchanger, and a humidifier. Therefore, by exchanging heat between the water flowing through the water circulation path 96 and the air inside the cabin 10, the air conditioning system 90 can warm the air inside the cabin 10. This can melt snow adhering to the glass surface of the cabin 10. Furthermore, air warmed by heated water may be sent into the cabin 10 using a blower. In this case, a movable louver may be provided at the outlet of the blower, and the air warmed by the heated water may be blown onto the entire glass surface of the cabin 10. In particular, since the glass surface of the cabin 10 is wide in the height direction, as described above, the air warmed by the heated water may be blown onto the entire glass surface of the cabin 10 by moving the movable louver up and down. This allows the warmed air to be blown onto the entire glass surface of the cabin 10.

[0099] As described above, in the de-icing mode, the pump motor 12 does not operate, and the glass surface of the cabin 10 is heated by the power supplied from the charging station 1301 to the battery 192.

[0100] As described above, in this embodiment, the shovel 200 is operated by driving the main pump 14 and includes the cabin 10 for operating the shovel 200, the pump motor 12 that drives the main pump 14, the battery 192 that supplies power to the pump motor 12, and the shovel controller 30 that controls the driving of the shovel 200. The shovel controller 30 is provided with a thawing mode that warms the glass surface of the cabin 10. The thawing mode warms the glass surface of the cabin 10 while the pump motor 12 is not operating. This allows the thawing mode to be executed while the main pump 14 is not driven, thereby improving safety when thawing the glass surface of the cabin 10. For example, the thawing mode can be executed while the shovel 200 is unmanned.

[0101] Furthermore, in this embodiment, the ice-thawing mode heats the glass surface of the cabin 10 using power supplied from an external power source connected to the battery 192. This makes it possible to heat the inside of the cabin 10 without consuming the battery 192. As a result, the operating time of the excavator 200 can be extended.

[0102] Here, when the inside of the cabin 10 is heated using the hydraulic oil of the shovel 200, the hydraulic oil of the shovel 200 needs to be heated by warm air. In that case, it takes time for the hydraulic oil to be warmed by the warm air, and therefore it takes time to warm the inside of the cabin 10. Therefore, in this embodiment, the defrosting mode heats the glass surface of the cabin 10 by exchanging heat between the water, which serves as a medium heated by the water heater 93, and the air inside the cabin 10. This makes it possible to warm the inside of the cabin 10 immediately after the defrosting mode is started, for example.

[0103] Thereafter, when the charging cable 1311 is unplugged from the rapid charging vehicle inlet 102 and the acquisition unit 301 acquires this information (YES in step ST18), the heating control unit 303 terminates the operation of the water pump 92 and controls the water heating heater 93 to terminate heating, thereby terminating the de-icing mode (step ST19).

[0104] As described above, in this embodiment, the shovel controller 30 ends the thawing mode when the connection between the battery 192 and the charging station 1301 is released. This allows the operator of the shovel 200 to end the thawing mode without having to operate a switch or the like. Furthermore, when the power supply from the charging station 1301, which is an external power source, is stopped, the operation of the air conditioning system 90 stops, thereby reducing power consumption of the battery 192.

[0105] Note that, because the open / closed state of the door of the cabin 10 is detected by the open / close sensor S2, the thawing mode may be terminated based on the open / closed state of the door of the cabin 10. For example, in order for the operator of the shovel 200 to perform work using the shovel 200, he or she opens the door of the cabin 10, gets into the cabin 10, and closes the door. Therefore, if the detection result of the open / close sensor S2 acquired by the acquisition unit 301 indicates that the door of the cabin 10 has been opened and closed, it may be determined that work using the shovel 200 will be started, and the thawing mode may be terminated. This makes it possible to terminate the thawing mode in accordance with the start of work using the shovel 200, thereby preventing a situation in which water generated when the ice is thawed refreezes and forms ice on the glass surface.

[0106] Furthermore, in this embodiment, after charging of battery 192 is completed, it is determined whether snow or ice has adhered to the glass surface of cabin 10, and if snow or ice has adhered to the glass surface of cabin 10, the de-icing mode is executed. However, it may also be determined whether snow or ice has adhered to the glass surface of cabin 10 when charging of battery 192 is started. In this case, charging of battery 192 may be started taking into consideration the time required to melt the snow or ice adhered to the glass surface of cabin 10. For example, if the time required to complete charging of battery 192 is eight hours and the time required to melt the snow or ice adhered to the glass surface of cabin 10 is one hour, charging of battery 192 may be started nine hours before the work start time, and the de-icing mode may be started when charging of battery 192 is completed.

[0107] In this manner, in a configuration in which the battery 192 is charged by being connected to an external power source, the shovel controller 30 starts the thawing mode at a timing determined by the charge status of the battery 192. This allows the thawing mode to be executed automatically after the battery 192 is charged. Also, the operator of the shovel 200 can heat the glass surface of the cabin 10 and remove snow and ice adhering to the glass surface without having to operate a switch or the like, thereby improving work efficiency.

[0108] Furthermore, in this embodiment, the acquisition unit 301 acquires, as weather information, the detection result of the snow accretion sensor S1 attached to the glass surface of the cabin 10, and the thawing mode is executed when snow accretion is detected. However, a camera (not shown) installed inside the cabin 10 may be used as an example of a detection means, and the acquisition unit 301 may acquire, as weather information, an image captured by the camera installed inside the cabin 10. In this case, for example, the determination unit 302 may determine whether snow or ice has adhered to the glass surface of the cabin 10 based on the image acquired by the acquisition unit 301, and execute the thawing mode when snow has adhered. In this way, the acquisition unit 301 acquires, as weather information, the detection result of the snow accretion sensor S1 or camera attached to the shovel 200, and executes the thawing mode when snow accretion is detected. This makes it possible to reliably determine that snow or ice has adhered to the glass surface of the cabin 10.

[0109] The acquisition unit 301 may acquire weather information for the current position of the shovel 200. For example, the current position of the shovel 200 may be determined using a GPS device (not shown) mounted on the shovel 200, weather forecast data may be received via the communication device T1, and weather information corresponding to the current position of the shovel 200 may be acquired from the weather forecast data via the communication device T1. The thawing mode may then be executed in accordance with the weather information corresponding to the current position of the shovel 200. In this case, the thawing mode may be combined with time information. For example, the thawing mode may be executed when the charging cable 1311 is connected to the rapid charging vehicle inlet 102 at a time when snow accumulation is expected. This allows the thawing mode to be executed in accordance with the weather conditions at the current position of the shovel 200.

[0110] In this way, the acquisition unit 301 acquires weather information, and the shovel controller 30 executes the thawing mode in accordance with the weather information acquired by the acquisition unit 301. This allows the thawing mode to be executed automatically in accordance with the weather conditions. Also, the operator of the shovel 200 can heat the glass surface of the cabin 10 and remove snow and ice adhering to the glass surface without having to operate a switch or the like, thereby improving work efficiency.

[0111] In this embodiment, the water circulating through the water circulation flow path 96 is heated by the water heater 93, and heat is exchanged between the heated water and the air inside the cabin 10, thereby warming the glass surface of the cabin 10. However, the glass surface of the cabin 10 may also be heated by using air as a heat exchange medium, heating the air using an air heater, and exchanging heat between the heated air and the air inside the cabin 10. Also, in an air conditioning system that heats the cabin 10 by directly blowing air heated by an air heater into the cabin 10, the glass surface of the cabin 10 may be heated by air heated by an air heater. In this way, the thawing mode can be executed without driving the main pump 14 by heating the glass surface of the cabin 10 using a function for heating the interior of the cabin 10, thereby improving safety when thawing the ice on the glass surface of the cabin 10.

[0112] Furthermore, in this embodiment, when the charging cable 1311 is connected to the rapid charging vehicle inlet 102, the battery 192 is charged first, and the thawing mode is executed after charging of the battery 192 is completed. However, charging of the battery 192 and execution of the thawing mode may be executed simultaneously.

[0113] (Other embodiments) Instead of or in addition to being configured to be operable by an operator inside the cabin 10, the shovel 200 may be configured to be remotely operable from outside the shovel 200. When the shovel 200 is remotely operated, the inside of the cabin 10 may be unmanned.

[0114] FIG. 5 is a diagram showing an example of a system in which a shovel 200 is remotely controlled.

[0115] As shown in FIG. 5, the excavator 200 may be operated from a remote control room RC.

[0116] The remote control room RC is equipped with a remote controller 40, a sound output device A2, an indoor imaging device C2, a display device D1, a communication device T2, etc. The remote control room RC also is equipped with a driver's seat DS where an operator OP who remotely operates the excavator 200 sits.

[0117] The remote controller 40 is a calculation device that executes various calculations. In this embodiment, the remote controller 40 is configured with a microcomputer including a CPU and memory, similar to the shovel controller 30. The various functions of the remote controller 40 are realized by the CPU executing programs stored in the memory.

[0118] The sound output device A2 is configured to output sound. In this embodiment, the sound output device A2 is a speaker and is configured to reproduce sound collected by a sound collection device (not shown) attached to the shovel 200.

[0119] The indoor imaging device C2 is configured to capture an image of the inside of the remote control room RC. In this embodiment, the indoor imaging device C2 is a camera installed inside the remote control room RC, and is configured to capture an image of the operator OP seated in the driver's seat DS.

[0120] The communication device T2 is configured to control wireless communication with the communication device T1 attached to the shovel 200.

[0121] A remote control device 126 including an engine speed adjustment dial 75 is provided near the driver's seat DS. The engine speed adjustment dial 75 is a dial for adjusting the speed of the engine 11 and is configured to be able to switch the engine speed between, for example, four levels. The remote control device 126 is provided with an operation sensor 29 for detecting the operation content of the remote control device 126. The operation sensor 29 is, for example, an inclination sensor that detects the inclination angle of the operation lever, or an angle sensor that detects the swing angle of the operation lever around the swing axis. The operation sensor 29 may be configured with other sensors such as a pressure sensor, a current sensor, a voltage sensor, or a distance sensor. The operation sensor 29 outputs information regarding the detected operation content of the remote control device 126 to the remote controller 40. The remote controller 40 generates an operation signal based on the received information and transmits the generated operation signal to the excavator 200. The operation sensor 29 may be configured to generate an operation signal. In this case, the operation sensor 29 may output the operation signal to the communication device T2 without passing through the remote controller 40.

[0122] The display device D1 is configured to display information relating to the situation around the shovel 200. In this embodiment, the display device D1 is a multi-display made up of nine monitors arranged in three rows and three columns, and is configured to be able to display the state of the space in front of, to the left of, and to the right of the shovel 200. Each monitor is a liquid crystal monitor, an organic EL monitor, or the like. However, the display device D1 may be made up of one or more curved monitors, or may be made up of a projector.

[0123] The display device D1 may be a display device that can be worn by the operator OP. For example, the display device D1 may be a head-mounted display configured to be able to transmit and receive information to and from the remote controller 40 via wireless communication. The head-mounted display may be connected to the remote controller 40 by wire. The head-mounted display may be a transparent head-mounted display or a non-transparent head-mounted display. The head-mounted display may be a monocular head-mounted display or a binocular head-mounted display.

[0124] The display device D1 is configured to display an image that enables the operator OP in the remote control room RC to visually recognize the surroundings of the shovel 200. In other words, the display device D1 displays an image so that the operator can confirm the situation around the shovel 200 as if he or she were inside the cabin 10 of the shovel 200, even though he or she is in the remote control room RC.

[0125] In a system configured in this manner, if an image of the outside (for example, in front of the shovel 200) captured from inside the cabin 10 of the shovel 200 is displayed on the display device D1, when snow adheres to the glass surface of the shovel 200, this is displayed on the display device D1, allowing the operator OP to recognize that snow has adhered to the glass surface of the shovel 200. Therefore, the operator OP can also specify execution of the thawing mode by operating the remote control device 126. When the operator OP specifies execution of the thawing mode by operating the remote control device 126, the thawing mode can be remotely executed if the charging cable 1311 is connected to the quick charging vehicle inlet 102. In this way, the shovel controller 30 may execute the thawing mode in response to an instruction from a remote control device that remotely operates the shovel 200. This allows the thawing mode to be executed from the remote control device that remotely operates the shovel 200. Furthermore, the operator OP remotely operating the shovel 200 can heat the glass surface of the cabin 10 and remove snow and ice adhering to the glass surface without having to operate a switch or the like, thereby improving work efficiency. Also, instead of the remote control room RC, a mobile communication terminal such as a smartphone that can communicate with the shovel 200 may be used as the remote control device. In this case, an image of the outside taken from inside the cabin 10 can be displayed on the screen of the mobile communication terminal, so that the worker working on the shovel 200 can recognize that snow and ice have adhered to the glass surface of the shovel 200 and can execute the ice-melting mode even if he or she is not at the work site. This allows the worker to start work immediately after arriving at the work site. [Explanation of symbols]

[0126] 1 Undercarriage 1L, 1R Travel hydraulic motor 2. Swivel mechanism 2M Swing Hydraulic Motor 3 Upper rotating body 4. Boom 5 Arm 6 buckets 7 Boom cylinder 8 Arm Cylinder 9 Bucket cylinder 10 Cabins 12 Pump motor 12s sensor 14 Main pump 15 Pilot pump 16 High-pressure hydraulic lines 17 Control valve 19 Battery Module 25 Pilot Line 26 Operating device 28 Signal Line 30 Excavator Controller 31 Pressure control valve 50 Output Device 52 Input Device 90 Air Conditioning System 91 HVAC 92 Water pump 93 Water heater 94 Reserve Tank 96 Water circulation channel 100 Power conversion device 110 DC Bus 126 Remote Control Device 191 Battery Controller 192 Battery 200 Shovel 301 Acquisition Department 302 Judgment section 303 Heating control unit 304 Charging control unit 305 Setting time holding section S1 Snow Accumulation Sensor S2 Open / Close Sensor T Hydraulic oil tank T1 communications equipment

Claims

1. A shovel operated by driving a hydraulic pump, an operator's cab for operating the shovel; an electric motor that drives the hydraulic pump; a battery that supplies power to the electric motor; a control unit that controls the drive of the shovel, The control unit has an ice-thawing mode that warms the glass surface of the driver's cab while the electric motor is not operating.

2. The excavator according to claim 1 , wherein the ice-thawing mode heats a glass surface of the operator's cab using power supplied from an external power source.

3. An acquisition unit for acquiring weather information, The shovel according to claim 1 , wherein the control unit executes the ice-melting mode in accordance with weather information acquired by the acquisition unit.

4. The shovel according to claim 3 , wherein the acquisition unit acquires weather information at a current location of the shovel.

5. The shovel according to claim 3 , wherein the acquisition unit acquires the weather information using a detection means attached to the shovel.

6. The shovel according to claim 1 , wherein the ice-thawing mode uses a function for heating the interior of the cab to warm a glass surface of the cab.

7. The shovel according to claim 6, wherein the defrosting mode warms a glass surface of the operator's cab by exchanging heat between a heated medium and air in the operator's cab.

8. The battery is charged by being connected to the external power source; The shovel according to claim 2 , wherein the control unit starts the ice-melting mode at a timing according to a charge state of the battery.

9. The shovel according to claim 8 , wherein the control unit terminates the ice-thawing mode when the connection between the battery and the external power supply is released.

10. The shovel according to claim 8 , wherein the control unit terminates the ice-melting mode based on an open / close state of a door of the operator's cab.

11. The shovel according to claim 1 , wherein the control unit executes the ice-melting mode in response to an instruction from a remote control device that remotely controls the shovel.

Images