JP2021147859A - Shovel - Google Patents

Abstract

To provide a technology capable of more properly adjusting degree of heat exchange in an apparatus exchanging heat with outside air, in a shovel.SOLUTION: A shovel in one embodiment of this disclosure comprises a plurality of fans 90 blowing air to a heat exchange apparatus exchanging heat with outside air (such as a radiator 62, an oil cooler 72, and a capacitor 82B). For example, there is an operation state case where only a part of the plurality of fans 90 is stopped or has a lower rotation speed than that of other fans 90.SELECTED DRAWING: Figure 5

Description

This disclosure relates to excavators.

Conventionally, the number of rotations of a fan that blows air toward a device (for example, an oil cooler) that exchanges heat with the outside air in response to a change in the temperature of a fluid (for example, hydraulic oil) flowing through the device. Is known (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2019-208568

However, in the case of the above technique, only the rotation speed of one fan is changed. Therefore, it is desirable that the degree of heat exchange (cooling degree and heating degree) in the target device can be adjusted more finely.

Therefore, in view of the above problems, it is an object of the present invention to provide a technique capable of more appropriately adjusting the degree of heat exchange in a device that exchanges heat with the outside air in the excavator.

In order to achieve the above object, in one embodiment of the present disclosure,
Equipped with multiple fans that blow air toward a given device that exchanges heat with the outside air,
Excavator is provided.

According to the above-described embodiment, it is possible to provide a technique capable of more appropriately adjusting the degree of heat exchange in a device that exchanges heat with the outside air in the excavator.

It is a side view of an excavator. It is a block diagram which shows an example of the structure of the excavator schematicly. It is a figure which shows an example of the cooling circuit of an electric drive system. It is a figure which shows an example of the heat pump cycle of an air conditioner. It is a figure which shows the 1st example of the arrangement of a radiator, an oil cooler, a condenser, and a fan. It is a figure which shows the 1st example of the arrangement of a radiator, an oil cooler, a condenser, and a fan. It is a flowchart which shows the 1st example of the control process of a radiator fan by a controller schematicly. It is a flowchart which shows the 1st example of the control process of a radiator fan by a controller schematicly. It is a flowchart which shows the 1st example of the control process of the oil cooler fan by a controller schematicly. It is a flowchart which shows the 1st example of the control process of the oil cooler fan by a controller schematicly. It is a flowchart which shows the 1st example of the control process of a condenser fan by a controller schematicly. It is a figure which shows the 2nd example of the arrangement of a radiator, an oil cooler, a condenser, and a fan. It is a figure which shows the 2nd example of the arrangement of a radiator, an oil cooler, a condenser, and a fan. It is a flowchart which shows the 2nd example of the control process of a radiator fan by a controller schematicly. It is a flowchart which shows the 2nd example of the control process of a radiator fan by a controller schematicly. It is a flowchart which shows the 2nd example of the control process of the oil cooler fan by a controller schematicly. It is a flowchart which shows the 2nd example of the control process of the oil cooler fan by a controller schematicly. It is a flowchart which shows the 2nd example of the control process of a condenser fan by a controller schematicly.

Hereinafter, modes for carrying out the invention will be described with reference to the drawings.

[Outline of excavator]
First, an outline of an excavator as an example of a working machine will be described with reference to FIG.

FIG. 1 is a side view showing an example of a shovel according to the present embodiment.

The excavator according to the present embodiment includes a lower traveling body 1, an upper swivel body 3 mounted on the lower traveling body 1 so as to be swivelable via the swivel mechanism 2, a boom 4, an arm 5, and a bucket 6 as attachments. , The cabin 10 on which the operator is boarded.

The lower traveling body 1 includes, for example, a pair of left and right crawlers, and the lower traveling bodies 1 self-propelled by being hydraulically driven by the traveling hydraulic motors 1A and 1B (see FIG. 2).

The upper swivel body 3 is electrically driven by a swivel motor 21 (see FIG. 2) described later through the swivel mechanism 2 to swivel with respect to the lower traveling body 1. Further, the upper swivel body 3 may be hydraulically driven by a swivel hydraulic motor instead of the swivel motor 21 through the swivel mechanism 2. In this case, the excavator of the present embodiment is a power source (engine) of a so-called hydraulic excavator in which all driven elements are hydraulically driven by hydraulic oil supplied from a main pump 14 (see FIG. 2) powered by an engine. ) Is replaced with the pump motor 12.

The boom 4 is vertically attached to the center of the front portion of the upper swing body 3, an arm 5 is attached to the tip of the boom 4 so as to be vertically rotatable, and a bucket 6 is vertically rotated to the tip of the arm 5. Can be installed. The boom 4, arm 5, and bucket 6 are hydraulically driven by the boom cylinder 7, arm cylinder 8, and bucket cylinder 9 as hydraulic actuators, respectively.

The bucket 6 is an example of an end attachment, and another end attachment may be attached to the tip of the arm 5 instead of the bucket 6 depending on the work content and the like. The other end attachment may be, for example, a bucket of a type different from that of the bucket 6, such as a slope bucket or a dredging bucket. Further, the other end attachment may be, for example, an end attachment of a type different from that of a bucket such as a breaker, a stirrer, or a grappler.

The cabin 10 is mounted on the left side of the front portion of the upper swing body 3, and inside the cabin 10, a driver's seat on which the operator sits, an operation device 26 described later, and the like are provided.

The excavator operates the driven elements such as the lower traveling body 1 (left and right crawlers), the upper turning body 3, the boom 4, the arm 5, and the bucket 6 in response to the operation of the operator boarding the cabin 10.

Further, the excavator may be configured to be operable by an operator boarding the cabin 10, or may be configured to be remotely controlled (remote control) from the outside of the excavator. When the excavator is remotely controlled, the inside of the cabin 10 may be unmanned. Hereinafter, the description will proceed on the premise that the operator's operation includes at least one of the operation of the cabin 10 with respect to the operation device 26 and the remote control of the external operator.

The remote control includes, for example, a mode in which the shovel is operated by an operation input regarding the actuator of the shovel performed by a predetermined external device. In this case, the excavator is equipped with a communication device capable of communicating with a predetermined external device, and for example, transmits image information (image captured) output by the image pickup device included in the peripheral information acquisition device 40 described later to the external device. good. Then, the external device may display the image information (captured image) received by the display device (hereinafter, “remote control display device”) provided in the external device. Further, various information images (information screens) displayed on the output device 50 (display device) inside the cabin 10 of the excavator may be similarly displayed on the remote control display device of the external device. As a result, the operator of the external device can remotely control the excavator while checking the display contents such as the captured image and the information screen showing the surrounding state of the excavator displayed on the remote control display device, for example. Then, the excavator operates the hydraulic actuator in response to the remote control signal indicating the content of the remote control received from the external device by the communication device, and causes the lower traveling body 1 (left and right crawlers), the upper turning body 3, and the boom. Driven elements such as 4, the arm 5, and the bucket 6 may be driven.

Further, the remote control may include a mode in which the excavator is operated by, for example, an external voice input or a gesture input to the excavator of a person (for example, a worker) around the excavator. Specifically, the excavator is a voice or work uttered by surrounding workers or the like through a voice input device (for example, a microphone) or a gesture input device (for example, an image pickup device) mounted on the excavator (own machine). Recognize gestures, etc. performed by people. Then, the excavator operates the actuator according to the recognized voice, gesture, etc., and is driven by the lower traveling body 1 (left and right crawlers), the upper rotating body 3, the boom 4, the arm 5, the bucket 6, and the like. You may drive the element.

Further, the excavator may automatically operate the actuator regardless of the content of the operator's operation. As a result, the excavator has a function of automatically operating at least a part of driven elements such as the lower traveling body 1 (crawler 1CL, 1CR), the upper rotating body 3, the boom 4, the arm 5, and the bucket 6 (so-called "automatic"). Realize "driving function" or "machine control function").

The automatic operation function is a function (so-called "semi-automatic operation") in which a driven element (hydraulic actuator) other than the driven element (hydraulic actuator) to be operated is automatically operated in response to an operator's operation on the operation device 26 or a remote control. Function ") may be included. Further, the automatic operation function is a function (so-called "fully automatic operation function") in which at least a part of a plurality of driven elements (hydraulic actuators) is automatically operated on the premise that there is no operation or remote control of the operator's operation device 26. ) May be included. When the fully automatic driving function is enabled in the excavator, the inside of the cabin 10 may be unmanned. Further, the semi-automatic operation function, the fully automatic operation function, and the like may include a mode in which the operation content of the driven element (hydraulic actuator) to be automatically operated is automatically determined according to a predetermined rule. In addition, for the semi-automatic operation function, fully automatic operation function, etc., the excavator autonomously makes various judgments, and according to the judgment results, the operation contents of the driven element (hydraulic actuator) to be autonomously operated. The mode in which is determined (so-called “autonomous driving function”) may be included.

[Excavator configuration]
Next, the configuration of the excavator according to the present embodiment will be described with reference to FIGS. 2 to 4 in addition to FIG.

FIG. 2 is a block diagram schematically showing an example of the configuration of the excavator according to the present embodiment. FIG. 3 is a diagram showing an example of a cooling circuit 60 of an electric drive system mounted on an excavator according to the present embodiment. FIG. 4 is a diagram showing an example of a heat pump cycle 82 of the air conditioner 80 mounted on the excavator according to the present embodiment.

In the figure, the mechanical power line is indicated by a double line, the high-pressure hydraulic line is indicated by a thick solid line, the pilot line is indicated by a broken line, and the electric drive / control line is indicated by a thin solid line.

<Flood drive system>
The excavator hydraulic drive system according to the present embodiment includes traveling hydraulic motors 1A and 1B, a boom cylinder 7, and an arm cylinder that hydraulically drive each of the driven elements such as the lower traveling body 1, the boom 4, the arm 5, and the bucket 6. 8 and a hydraulic actuator such as a bucket cylinder 9 are included. The excavator hydraulic drive system according to the present embodiment includes a pump motor 12, a main pump 14, and a control valve 17.

The pump motor 12 is a power source for the hydraulic drive system. The pump motor 12 is, for example, an IPM (Interior Permanent Magnet) motor. The pump motor 12 is connected to the high-voltage power supply including the power storage device 19 and the swivel motor 21 via the inverter 18A. The pump motor 12 is driven by three-phase AC power supplied from the power storage device 19 and the swivel motor 21 via the inverter 18A to drive the main pump 14 and the pilot pump 15. The drive control of the pump motor 12 may be executed by the inverter 18A under the control of the controller 30B described later.

The main pump 14 sucks the hydraulic oil from the hydraulic oil tank T and discharges it to the high-pressure hydraulic line 16 to supply the hydraulic oil to the control valve 17 through the high-pressure hydraulic line 16. The main pump 14 is driven by a pump motor 12. The main pump 14 is, for example, a variable displacement hydraulic pump, and a regulator (not shown) controls the angle (tilt angle) of the swash plate under the control of the controller 30A, which will be described later. As a result, the main pump 14 can adjust the stroke length of the piston and control the discharge flow rate (discharge pressure).

The control valve 17 is a hydraulic control device that controls a hydraulic drive system in response to an operator's operation or an operation command corresponding to an automatic operation function. As described above, the control valve 17 is connected to the main pump 14 via the high-pressure hydraulic line 16 and uses hydraulic oil supplied from the main pump 14 as hydraulic actuators (running hydraulic motors 1A and 1B, boom cylinder 7, arm cylinder). 8 and the bucket cylinder 9) can be selectively supplied. For example, the control valve 17 is a valve unit including a plurality of control valves (direction switching valves) that control the flow rate and the flow direction of the 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 actuator is discharged from the control valve 17 to the hydraulic oil tank T.

<Electric drive system>
The electric drive system of the excavator according to the present embodiment includes a pump motor 12, a sensor 12s, and an inverter 18A. Further, the electric drive system of the excavator according to the present embodiment includes the swivel drive device 20, the sensor 21s, and the inverter 18B. The electric drive system of the excavator according to the present embodiment includes a high-voltage power source configured by a power storage device 19 or the like.

The sensor 12s includes a current sensor 12s1, a voltage sensor 12s2, and a rotation state sensor 12s3.

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, in the power path between the pump motor 12 and the inverter 18A. The detection signals corresponding to the currents of the three phases of the pump motor 12 detected by the current sensor 12s1 are directly taken into the inverter 18A through the communication line. Further, the detection signal may be taken into the controller 30B through the communication line and input to the inverter 18A via the controller 30B.

The voltage sensor 12s2 detects the applied voltage of each of the three phases of the pump motor 12. The voltage sensor 12s2 is provided, for example, in the power path between the pump motor 12 and the inverter 18A. The detection signal corresponding to the applied voltage of each of the three phases of the pump motor 12 detected by the voltage sensor 12s2 is directly taken into the inverter 18A through the communication line. Further, the detection signal may be taken into the controller 30B through the communication line and input to the inverter 18A via the controller 30B.

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

The inverter 18A drives and controls the pump motor 12 under the control of the controller 30B. The inverter 18A defines, for example, a conversion circuit that converts DC power into three-phase AC power or three-phase AC power into DC power, a drive circuit that switches the conversion circuit, and the operation of the drive circuit. A control circuit for outputting a control signal (for example, a PWM (Pulse Width Modulation) signal) is included.

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. Further, the control circuit of the inverter 18A sequentially determines the rotation angle of the rotation shaft of the pump motor 12 and the like based on the detection signal of the current sensor 12s1 and the detection signal of the voltage sensor 12s2 (or the voltage command value generated in the control process). By estimating, the operating state of the pump motor 12 may be grasped.

The swivel drive device 20 includes a swivel motor 21, a resolver 22, a mechanical brake 23, and a swivel reducer 24. Under the control of the controller 30B and the inverter 18B, the turning electric motor 21 performs a power running operation for turning and driving the upper turning body 3 and a regenerative operation for turning and braking the upper turning body 3 by generating regenerative power. The swivel motor 21 is connected to a high-voltage power source (that is, a power storage device 19) via an inverter 18B, and is driven by three-phase AC power supplied from the power storage device 19 via the inverter 18B. Further, the swivel motor 21 supplies regenerative power to the power storage device 19 and the pump motor 12 via the inverter 18B. As a result, the power storage device 19 can be charged and the pump motor 12 can be driven by the regenerative electric energy. The switching control between the power running operation and the regenerative operation of the turning motor 21 may be executed by the inverter 18B under the control of the controller 30B, for example. A resolver 22, a mechanical brake 23, and a swivel reducer 24 are connected to the rotary shaft 21A of the swivel motor 21.

The resolver 22 detects the rotation state (for example, rotation position (rotation angle), rotation speed, etc.) of the turning motor 21. The detection signal corresponding to the rotation angle or the like detected by the resolver 22 may be directly taken into the inverter 18B through the communication line. Further, the detection signal may be taken into the controller 30B through the communication line and input to the inverter 18B via the controller 30B.

The mechanical brake 23 mechanically generates a braking force with respect to the rotating shaft 21A of the turning motor 21 under the control of the controller 30B. As a result, the mechanical brake 23 can perform turning braking of the upper turning body 3 and maintain the stopped state of the upper turning body 3.

The swivel speed reducer 24 is connected to the rotating shaft 21A of the swivel motor 21 and decelerates the output (torque) of the swivel motor 21 at a predetermined reduction ratio to increase the torque and swivel the upper swivel body 3. Drive. That is, during the power running operation, the turning electric motor 21 swivels and drives the upper swivel body 3 via the swivel speed reducer 24. Further, the turning speed reducer 24 increases the inertial rotational force of the upper turning body 3 and transmits it to the turning electric motor 21 to generate regenerative electric power. That is, during the regenerative operation, the swivel electric motor 21 regenerates power by the inertial rotational force of the upper swivel body 3 transmitted via the swivel speed reducer 24, and swivels and brakes the upper swivel body 3.

The sensor 21s includes a current sensor 21s1 and a voltage sensor 21s2.

The current sensor 21s1 detects the currents of the three phases (U phase, V phase, and W phase) of the swivel motor 21. The current sensor 21s1 is provided, for example, in the power path between the turning motor 21 and the inverter 18B. The detection signal corresponding to the current of each of the three phases of the turning motor 21 detected by the current sensor 21s1 may be directly taken into the inverter 18B through the communication line. Further, the detection signal may be taken into the controller 30B through the communication line and input to the inverter 18B via the controller 30B.

The voltage sensor 21s2 detects the applied voltage of each of the three phases of the turning motor 21. The voltage sensor 21s2 is provided, for example, in the power path between the turning motor 21 and the inverter 18B. The detection signal corresponding to the applied voltage of each of the three phases of the turning motor 21 detected by the voltage sensor 21s2 is directly taken into the inverter 18B through the communication line. Further, the detection signal may be taken into the controller 30B through the communication line and input to the inverter 18B via the controller 30B.

The inverter 18B drives and controls the turning motor 21 under the control of the controller 30B. The inverter 18B defines, for example, a conversion circuit that converts DC power into three-phase AC power or three-phase AC power into DC power, a drive circuit that switches the conversion circuit, and the operation of the drive circuit. A control circuit for outputting a control signal (for example, a PWM signal) is included.

For example, the control circuit of the inverter 18B performs speed feedback control and torque feedback control on the turning motor 21 based on the detection signals of the current sensor 21s1, the voltage sensor 21s2, and the resolver 22.

For example, as shown in FIG. 3, the inverters 18A and 18B may be housed in, for example, one housing, and the inverter unit 18 may be integrally formed.

At least one of the drive circuit and the control circuit of the inverter 18B may be provided outside the inverter 18B.

The power storage device 19 is charged (stored) by being connected to an external commercial power source with a predetermined cable, and the charged (stored) power is transferred to a pump motor via a DC (Direct Current) bus 110. It is supplied to 12 and the turning motor 21. Further, the power storage device 19 charges the generated power (regenerative power) of the turning motor 21. The power storage device 19 is, for example, a lithium ion battery and has a relatively high output voltage (for example, several hundred volts).

A power conversion device for boosting the output voltage of the power storage device 19 and applying it to the pump motor 12 and the swivel motor 21 may be provided between the power storage device 19 and the DC bus 110. In this case, the power conversion device boosts the power of the power storage device 19, or lowers the power of the pump motor 12 and the swivel motor 21 via the inverters 18A and 18B, and stores the power in the power storage device 19. The power conversion device may switch between a step-up operation and a step-down operation so that the voltage value of the DC (Direct Current) bus 110 falls within a certain range according to the operating state of the pump motor 12 and the swivel motor 21. .. The switching control between the step-up operation and the step-down operation of the power conversion device is executed by the controller 30B based on, for example, the voltage detection value of the DC bus 110, the voltage detection value of the power storage device 19, and the current detection value of the power storage device 19. good.

<Operation system>
The shovel operating system according to the present embodiment includes a pilot pump 15, an operating device 26, and a pressure control valve 31.

The pilot pump 15 supplies pilot pressure to various hydraulic devices (for example, pressure control valve 31) mounted on the excavator via the pilot line 25. As a result, the pressure control valve 31 can supply the pilot pressure to the control valve 17 according to the operation content (for example, the operation amount and the operation direction) of the operation device 26 under the control of the controller 30A. Therefore, the controller 30A and the pressure control valve 31 can realize the operation of the driven element (hydraulic actuator) according to the operation content of the operator with respect to the operation device 26. Further, the pressure control valve 31 can supply the pilot pressure to the control valve 17 according to the content of the remote control specified by the remote control signal under the control of the controller 30A. The pilot pump 15 is, for example, a fixed-capacity hydraulic pump, and is driven by a pump motor 12 as described above.

The operating device 26 is provided within reach of the operator in the driver's seat of the cabin 10, and the operator can use each of the driven elements (that is, the left and right crawlers of the lower traveling body 1, the upper swivel body 3, the boom 4, and the arm 5). , And bucket 6 etc.). In other words, the operating device 26 is a hydraulic actuator (for example, traveling hydraulic motors 1A, 1B, boom cylinder 7, arm cylinder 8, bucket cylinder 9, etc.) or an electric actuator (swivel) in which the operator drives each driven element. It is used to operate the electric motor 21 and the like). The operation device 26 is, for example, an electric type, and outputs an electric signal (hereinafter, “operation signal”) according to the operation content by the operator. The operation signal output from the operation device 26 is taken into the controller 30A. As a result, the control device 30 including the controller 30A controls the pressure control valve 31 and the inverter 18B, and the driven element (actuator) of the excavator is adjusted according to the operation content of the operator and the operation command corresponding to the automatic operation function. The operation can be controlled.

The operating device 26 includes, for example, levers 26A-26C. The lever 26A may be configured to be able to accept operations related to each of the arm 5 (arm cylinder 8) and the upper swivel body 3 (swivel operation) according to, for example, operations in the front-rear direction and the left-right direction. The lever 26B may be configured to be able to accept operations related to the boom 4 (boom cylinder 7) and the bucket 6 (bucket cylinder 9) in response to operations in the front-rear direction and the left-right direction, for example. The lever 26C may be configured to be able to accept the operation of the lower traveling body 1 (crawler), for example.

When the control valve 17 is composed of an electromagnetic pilot type hydraulic control valve (direction switching valve), the operation signal of the electric operation device 26 is directly input to the control valve 17, and each hydraulic control valve operates. The mode may be such that the operation is performed according to the operation content of the device 26. Further, the operation device 26 may be 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.

The pressure control valve 31 outputs a predetermined pilot pressure under the control of the controller 30A by using the hydraulic oil supplied from the pilot pump 15 through the pilot line 25. 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.

<Control system>
The shovel control system according to the present embodiment includes a control device 30, an ambient information acquisition device 40, an output device 50, an input device 52, a temperature sensor 54, and an oil temperature sensor 56.

The control device 30 includes controllers 30A to 30C.

The respective functions of the controllers 30A to 30C may be realized by arbitrary hardware or a combination of arbitrary hardware and software. For example, the controllers 30A to 30C are a processor such as a CPU (Central Processing Unit), a memory device (main storage device) such as a RAM (Random Access Memory), and a non-volatile auxiliary storage device such as a ROM (Read Only Memory), respectively. , And a computer including an interface device with the outside and the like.

The controller 30A controls the drive of the excavator in cooperation with various controllers constituting the control device 30 including the controllers 30B and 30C.

For example, the controller 30A outputs a control command to the pressure control valve 31 in response to an operation signal input from the operation device 26, and causes the pressure control valve 31 to output a pilot pressure according to the operation content of the operation device 26. As a result, the controller 30A can realize the operation of the driven element (hydraulic actuator) of the excavator corresponding to the operation content of the electric operation device 26.

Further, when the excavator is remotely controlled, the controller 30A may control the remote control, for example. Specifically, the controller 30A may output a control command to the pressure control valve 31 and output a pilot pressure according to the content of the remote control from the pressure control valve 31. As a result, the controller 30A can realize the operation of the excavator (driven element) corresponding to the content of the remote control.

Further, the controller 30A may control the automatic driving function, for example. Specifically, the controller 30A may output a control command to the pressure control valve 31 and apply a pilot pressure corresponding to the operation command corresponding to the automatic operation function from the pressure control valve 31 to the control valve 17. As a result, the controller 30A can realize the operation of the driven element (hydraulic actuator) of the excavator corresponding to the automatic operation function.

Further, the controller 30A may integrally control the operation of the entire excavator (various devices mounted on the excavator) based on bidirectional communication with various controllers such as the controllers 30B and 30C.

Further, the controller 30A may control, for example, a function of automatically stopping the main pump 14 (hereinafter, “pump stop function”).

Specifically, the controller 30A uses the main pump 14 when the excavator is not being operated (operated by the operating device 26 or remotely) by the operator while the excavator is operating (during operation). It may be stopped automatically. As a result, the controller 30A can stop the operation of the main pump 14, that is, the pump motor 12, which is unnecessary when the excavator is not operated. Therefore, the electric power of the power storage device 19 consumed by the pump motor 12 can be suppressed. Further, the controller 30A may stop the main pump 14 when a predetermined input indicating an intention to stop the main pump 14 is received through the input device 52 while the excavator is in operation (during operation). As a result, the controller 30A can stop the main pump 14 (pump electric motor 12) by reflecting the intention of the operator. Therefore, for example, the operator inputs a predetermined input through the input device 52 in a situation where the operating noise of the main pump 14 (pump motor 12) in operation hinders communication with surrounding workers. By doing so, it is possible to temporarily reduce the operating noise and communicate with the surrounding workers.

For example, the control device 30 (controllers 30A and 30B) has a main pump 14, that is, a pump motor, regardless of whether or not the operation device 26 is operated when the excavator is started (for example, when the key switch is turned on). 12 is started. As a result, the control device 30 can start the pump motor 12 once when the excavator is started, and shift the pump motor 12 to a controllable state. In addition, the control device 30 can start the pump motor 12 once when the excavator is started, and perform diagnostic processing such as the presence or absence of an abnormality in the pump motor 12. For example, the controller 30B diagnoses the presence or absence of an abnormality by energizing the pump motor 12 through the inverter 18A. If there is an abnormality, the controller 30B may notify the operator that there is an abnormality in the pump motor 12 through the output device 50 or the like. On the other hand, the controller 30B may stop the pump motor 12 by the pump stop function when there is no abnormality in the pump motor 12 and the operation of the operating device 26 is not started thereafter. Then, the controller 30A automatically starts the pump motor 12 when the operator's operation is started, and then automatically stops the pump motor 12 every time the continuation of the non-operation state is detected, and the operator When the operation is started, the process of automatically starting the pump motor 12 may be repeated.

Further, the controller 30A may control, for example, the operation and stop of the fan 90. Details will be described later (see FIGS. 5 to 18).

The controller 30B controls the drive of the electric drive system based on various information input from the controller 30A (for example, a control command including an operation signal of the operation device 26).

For example, the controller 30B may drive the inverter 18B based on the operation content of the operating device 26 to perform switching control of the operating state (power running operation and regenerative operation) of the turning motor 21. Further, for example, when the excavator is remotely controlled, the controller 30B may drive the inverter 18B and perform switching control of the operating state (power running operation and regenerative operation) of the turning motor 21 based on the content of the remote control. .. Further, for example, when the automatic operation function of the excavator is enabled, the controller 30B drives the inverter 18B based on the operation command corresponding to the automatic operation function, and determines the operating state (power running operation and regenerative operation) of the turning motor 21. Switching control may be performed.

When the above-mentioned power conversion device is provided between the power storage device 19 and the DC bus 110, the controller 30B drives the power conversion device based on, for example, the operating state of the operation device 26, and boosts the power conversion device. Operation and step-down operation, in other words, switching control between the discharge state and the charge state of the power storage device 19 may be performed. Further, for example, when the excavator is remotely controlled, the controller 30B may drive the power conversion device and perform switching control between the discharge state and the charge state of the power storage device 19 based on the content of the remote control. Further, for example, when the automatic operation function of the excavator is enabled, the controller 30B drives the power conversion device based on the operation command corresponding to the automatic operation function, and controls switching between the discharge state and the charge state of the power storage device 19. You may go.

Further, the controller 30B may control the stop and start of the pump motor 12 in response to a control command from the controller 30A regarding the pump stop function.

The controller 30C controls the peripheral monitoring function of the excavator.

The controller 30C determines a predetermined value around the excavator based on, for example, information about the situation of the three-dimensional space around the excavator (for example, detection information about an object around the excavator and its position) taken from the surrounding information acquisition device 40. Detects an object and its position (hereinafter referred to as "monitoring target").

Further, for example, when the controller 30C detects a monitoring target in an area relatively close to the excavator, the controller 30C outputs an alarm through an output device 50 (for example, a display device, a sound output device, etc.) in the cabin 10 room. good.

The functions of the controllers 30B and 30C may be integrated into the controller 30A. That is, the various functions realized by the control device 30 may be realized by one controller, or may be distributed and realized by two or more controllers that are appropriately set.

The surrounding information acquisition device 40 outputs information regarding the situation of the three-dimensional space around the excavator. The ambient information acquisition device 40 may include, for example, an ultrasonic sensor, a millimeter wave radar, a monocular camera, a stereo camera, a depth camera, a LIDAR (Light Detection and Ranging), a range image sensor, an infrared sensor, and the like. The output information of the surrounding information acquisition device 40 is taken into the controller 30C.

The output device 50 is provided in the cabin 10 and outputs various information to the operator under the control of the control device 30 (for example, the controller 30A). The output device 50 includes, for example, a display device that outputs (notifies) information to the operator by a visual method. The display device may be installed in a place easily visible to the operator in the cabin 10, and may display various information images under the control of the controller 30A. The display device is, for example, a liquid crystal display or an organic EL (Electroluminescence) display. Further, the output device 50 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, or the like.

The input device 52 is provided in the cabin 10 and receives various inputs from the operator. The input device 52 may include, for example, an operation input device that receives an operator's operation input. The operation input device includes, for example, a button, a toggle, a lever, a touch panel, a touch pad, and the like. Further, the input device 52 may include, for example, a voice input device that accepts voice input from the operator and a gesture input device that accepts gesture input from the operator. The voice input device includes, for example, a microphone that acquires the voice of the operator in the cabin 10. Further, the gesture input device includes, for example, an indoor camera capable of capturing the state of the operator's gesture in the cabin 10. The signal corresponding to the input from the operator received by the input device 52 is taken into the control device 30 (for example, the controller 30A).

The temperature sensor 54 detects the temperature of the electric drive system device to be cooled by the cooling circuit 60, which will be described later. The temperature sensor 54 includes, for example, a temperature sensor that detects the temperature of the pump motor 12. Further, the temperature sensor 54 includes a temperature sensor that detects the temperature of the inverter 18A. Further, the temperature sensor 54 includes a temperature sensor that detects the temperature of the inverter 18B. Further, the temperature sensor 54 includes, for example, a temperature sensor that detects the temperature of the power storage device 19. Further, the temperature sensor 54 includes, for example, a temperature sensor that detects the temperature of the turning motor 21. Further, the temperature sensor 54 includes, for example, a temperature sensor that detects the temperature of the DC-DC converter 44 described later. The detection signal of the temperature sensor 54 is taken into, for example, the controller 30A. As a result, the controller 30A can grasp the temperature state of the electric drive system equipment.

When a power conversion device is provided between the power storage device 19 and the DC bus 110, the temperature sensor may include a temperature sensor that grasps the temperature state of the power conversion device.

The oil temperature sensor 56 detects the temperature of the hydraulic oil that drives the hydraulic actuator (hereinafter, “hydraulic oil temperature”). The oil temperature sensor 56 may detect, for example, the temperature of the hydraulic oil inside the hydraulic oil tank T. The detection signal of the oil temperature sensor 56 is taken into, for example, the controller 30A. As a result, the controller 30A can grasp the temperature state of the hydraulic oil.

<Other components>
The excavator according to the present embodiment includes a DC-DC converter 44, a battery 46, a cooling circuit 60, an oil cooler 70, an air conditioner 80, and a fan 90.

The DC-DC converter 44 is provided on the upper swing body 3, for example, and steps down a very high voltage DC power output from the power storage device 19 to a predetermined voltage (for example, about 24 volts) and outputs the DC power. The output power of the DC-DC converter 44A is supplied to the battery 46 and charged (stored), or is supplied to an electric device driven by the power of the battery 46 such as the controllers 30A to 30C.

The DC-DC converter 44 may be replaced with an alternator. In this case, the alternator may be provided on the upper swing body 3 and generate electricity by the power of the pump motor 12. The generated power of the alternator is supplied to the battery 46 as in the case of the DC-DC converter 44, and is charged (stored) in the battery 46 or supplied to electric devices such as the controllers 30A to 30C that are driven by the power of the battery 46. It is done.

The battery 46 is provided on the upper swing body 3 and has a relatively low output voltage (eg, 24 volts). The battery 46 supplies electric power to electric devices other than the electric drive system (for example, controllers 30A to 30C, air conditioner 80, etc.) that require relatively high electric power. The battery 46 is, for example, a lead storage battery, a lithium ion battery, or the like, and is charged by the output power of the DC-DC converter 44 as described above.

The cooling circuit 60 cools the equipment of the electric drive system and the like. For example, as shown in FIG. 3, the equipment to be cooled by the cooling circuit 60 includes a pump motor 12, an inverter unit 18, a power storage device 19, a swivel drive device 20, a DC-DC converter 44, and the like.

As shown in FIG. 3, the cooling circuit 60 includes a radiator 62, a water pump 64, and a refrigerant flow path 66A, 66B, 66C, 66C1, 66C2, 66D, 66D1, 66D2, 66E, 66F.

The radiator 62 cools the refrigerant (for example, cooling water) in the cooling circuit 60. Specifically, the radiator 62 cools the refrigerant by exchanging heat between the ambient air and the refrigerant.

The water pump 64 sucks the refrigerant from the refrigerant flow path 66F and discharges it to the refrigerant flow path 66A to circulate the refrigerant in the cooling circuit 60.

The refrigerant flow path 66A connects between the water pump 64 and the swirl drive device 20, and allows the refrigerant discharged from the water pump 64 to flow into the refrigerant flow path inside the swirl drive device 20. As a result, the turning motor 21 and the like in the turning drive device 20 can be cooled by the refrigerant. The refrigerant that has passed through the inside of the swivel drive device 20 flows out to the refrigerant flow path 66B.

The refrigerant flow path 66B connects between the swirl drive device 20 and the power storage device 19, and allows the refrigerant flowing out of the swirl drive device 20 to flow into the refrigerant flow path inside the power storage device 19. As a result, the power storage device 19 can be cooled by the refrigerant. The refrigerant that has passed through the inside of the power storage device 19 flows out to the refrigerant flow path 66C.

The refrigerant flow paths 66C, 66C1, 66C2 connect the power storage device 19 to the inverter unit 18 and the DC-DC converter 44, and allow the refrigerant flowing out of the power storage device 19 to flow inside the inverter unit 18 and the DC-DC converter 44. Inflow into the refrigerant flow path of. Specifically, the refrigerant flow path 66C to which one end is connected to the power storage device 19 branches into the refrigerant flow paths 66C1 and 66C2 at the other end, and the refrigerant flow paths 66C and 66C2 are the inverter unit 18 and DC-, respectively. It is connected to the DC converter 44. As a result, the inverters 18A and 18B and the DC-DC converter 44 included in the inverter unit 18 can be cooled. The refrigerant that has passed through the inside of the inverter unit 18 flows out to the refrigerant flow path 66D1. Further, the refrigerant that has passed through the inside of the DC-DC converter 44 flows out to the refrigerant flow path 66D2.

The refrigerant flow paths 66D, 66D1, 66D2 are connected between the inverter unit 18 and the DC-DC converter 44 and the pump motor 12, and the refrigerant flowing out from the inverter unit 18 and the DC-DC converter 44 is connected to the pump motor 12. It flows into the internal refrigerant flow path. Specifically, the refrigerant flow paths 66D1 and 66D2, one ends of which are connected to the inverter unit 18 and the DC-DC converter 44, respectively, merge with one end of the refrigerant flow path 66D, and the other end of the refrigerant flow path 66D is for a pump. It is connected to the electric motor 12. As a result, the pump motor 12 can be cooled by the refrigerant. The refrigerant that has passed through the inside of the pump motor 12 flows out to the refrigerant flow path 66E.

When a power conversion device is provided between the power storage device 19 and the DC bus 110, the power conversion device may be cooled by the cooling circuit 60. In this case, the power conversion device may be arranged in parallel with the inverter unit 18 and the DC-DC converter 44 in the cooling circuit 60, and may be cooled by the refrigerant flowing out from the power storage device 19. Further, the DC-DC converter 44 may be air-cooled. In this case, the refrigerant flow paths 66C2 and 66D2 are omitted.

The refrigerant flow path 66E connects between the pump motor 12 and the radiator 62, and supplies the refrigerant flowing out of the pump motor 12 to the radiator 62. As a result, by cooling the various devices of the electric drive system, the refrigerant whose temperature has risen can be cooled by the radiator, and the various devices of the electric drive system can be returned to a coolable state again.

The refrigerant flow path 66F connects between the radiator 62 and the water pump 64, and supplies the refrigerant cooled by the radiator 62 to the water pump 64. The water pump 64 can circulate the refrigerant cooled by the radiator 62 in the cooling circuit 60.

The oil cooler 70 is provided in, for example, a return oil passage between the control valve 17 and the hydraulic oil tank T, and cools the hydraulic oil in the hydraulic drive system. Specifically, the oil cooler 70 cools the hydraulic oil by exchanging heat between the surrounding air and the hydraulic oil flowing inside.

The air conditioner 80 adjusts the temperature, humidity, and the like in the cabin 10. The air conditioner 80 operates on the electric power supplied from, for example, the DC-DC converter 44 or the battery 46. The air conditioner 80 is, for example, a heat pump type for both cooling and heating, and includes a heat pump cycle 82.

The air conditioner 80 may include, for example, a refrigeration cycle and a heater for heating instead of the heat pump cycle 82. The heater for heating is, for example, a PTC (Positive Temperature Coefficient), a combustion type heater, or the like.

As shown in FIG. 4, the heat pump cycle 82 includes a compressor 82A, a condenser 82B, an expansion valve 82C, and an evaporator 82D.

The arrow in FIG. 4 represents the flow of the refrigerant during the cooling operation of the air conditioner 80, and the flow of the refrigerant during the heating operation of the air conditioner 80 is in the opposite direction.

The compressor 82A compresses the refrigerant in the heat pump cycle 82. The compressor 82A includes, for example, a built-in electric motor, an inverter circuit for driving the electric motor, and the like, and is electrically driven by electric power supplied from the power storage device 19. The refrigerant compressed by the compressor 82A is sent to the condenser 82B during the cooling operation of the air conditioner 80, and is sent to the evaporator 82D during the heating operation of the air conditioner 80.

The compressor 82A may be mechanically driven by the pump motor 12.

The condenser 82B is compressed by the compressor 82A during the cooling operation of the air conditioner 80, and cools the refrigerant in a gaseous state in which the temperature has risen relatively high. Specifically, the condenser 82B dissipates the heat of the refrigerant to the outside air by exchanging heat between the refrigerant flowing inside and the outside air, and cools the refrigerant. The refrigerant cooled by the capacitor 82B changes to a liquid state.

Further, during the heating operation of the air conditioner 80, the condenser 82B takes heat from the outside air by heat exchange between the refrigerant flowing inside and the outside air, and is depressurized through the expansion valve 82C to lower the temperature to a relatively low temperature. Raise the temperature of the refrigerant.

The expansion valve 82C sharply lowers the pressure of the passing refrigerant and lowers the temperature of the refrigerant. The expansion valve 82C sharply lowers the pressure of the liquid and high-pressure refrigerant sent from the condenser 82B during the cooling operation of the air conditioner 80, and lowers the temperature. Further, the expansion valve 82C sharply lowers the pressure of the refrigerant in the liquid state and the high pressure state sent from the evaporator 82D during the heating operation of the air conditioner 80, and lowers the temperature.

The evaporator 82D exchanges heat between the refrigerant flowing inside and the air sent from the air conditioner 80 into the cabin 10. The evaporator 82D removes heat from the air by a relatively low temperature refrigerant (gas-liquid mixed state) sent from the expansion valve 82C during the cooling operation of the air conditioner 80, and removes the air sent into the cabin 10. cool. Further, the evaporator 82D warms the air sent into the cabin 10 in a form in which the air takes heat from the relatively high temperature refrigerant (gas state) sent from the compressor 82A during the heating operation of the air conditioner 80. ..

The fan 90 operates under the control of the control device 30 (for example, the controller 30A) and blows air toward a predetermined device (hereinafter, “heat exchange device”) that exchanges heat with the outside air. The fan 90 operates on the electric power supplied from, for example, the DC-DC converter 44 or the battery 46.

The fan 90 may, for example, blow air toward the radiator 62 to cool the radiator 62, as shown in FIG. As a result, air capable of exchanging heat with the refrigerant flowing inside is sequentially supplied around the radiator 62, and the degree of cooling of the refrigerant by the radiator 62 can be increased. ..

Further, the fan 90 may cool the oil cooler 70 by blowing air toward the oil cooler 70, for example, as shown in FIG. As a result, air capable of exchanging heat with the hydraulic oil flowing inside is sequentially supplied around the oil cooler 70, and the degree of cooling of the hydraulic oil by the oil cooler 70 is adjusted. Can be enhanced.

Further, for example, as shown in FIG. 4, the fan 90 may blow air toward the condenser 82B to cool or heat the condenser 82B. As a result, air capable of exchanging heat with the refrigerant flowing inside is sequentially supplied around the condenser 82B, and the degree of cooling and heating of the refrigerant by the condenser 82B is increased. be able to.

[First example of fan control method]
Next, a first example of the control method of the fan 90 will be described with reference to FIGS. 5 to 11.

<Arrangement of heat exchange equipment and fans>
First, the arrangement of the heat exchange device and the fan 90 according to this example will be described.

5 and 6 are a front view and a side view showing a first example of the arrangement of the radiator 62, the oil cooler 70, the condenser 82B, and the fan 90. Hereinafter, for convenience, the arrangement relationship will be described using the directions in the figure (up, down, left, right, front, and back).

The radiator 62, the oil cooler 70, the condenser 82B, and the fan 90 are provided, for example, on the rear left side of the upper swing body 3.

As shown in FIGS. 5 and 6, the radiator 62 and the oil cooler 70 are of the downflow type, respectively, and tanks are arranged at both ends in the vertical direction. The radiator 62 and the oil cooler 70 have a vertically long rectangular shape that is longer in the vertical direction than in the horizontal direction, and are arranged side by side.

The condenser 82B has a horizontally long rectangular shape that is longer in the left-right direction than in the up-down direction, and is arranged adjacent to the radiator 62 and the oil cooler 70.

The fan 90 includes fans 90A to 90F.

The fans 90A and 90B are arranged behind the radiator 62, and blow air to the radiator 62 by sucking air from the front to the rear. The fans 90A and 90B are arranged side by side so that the fan 90A is on the upper side and the fan 90B is on the lower side. Hereinafter, the fans 90A and 90B may be comprehensively or individually referred to as "radiator fans".

The fans 90C and 90D are arranged behind the oil cooler 70, and blow air to the oil cooler 70 by sucking air from the front to the rear. The fans 90C and 90D are arranged side by side so that the fans 90C and 90C are on the upper side and the fans 90D are on the lower side. Hereinafter, the fans 90C and 90D may be collectively or individually referred to as "oil cooler fans".

The fans 90E and 90F are arranged behind the condenser 82B, and blow air to the condenser 82B by sucking air from the front to the back. The fans 90E and 90F are arranged side by side so that the fan 90E is on the right side and the fan 90F is on the left side.

As described above, in this example, a plurality of (two in this example) fans 90 capable of blowing air to one heat exchange device (an example of a predetermined device) are installed.

As a result, as will be described later, the control device 30 may stop only some of the fans 90 or have a relative rotation speed according to the degree of heat exchange (cooling degree or heating degree) required for the heat exchange device. It can be operated in a low state. Therefore, the control device 30 can finely adjust the degree of heat exchange of the heat exchanger.

In particular, the calorific value of the electric drive system of the present embodiment is smaller than the calorific value of the engine in the excavator on which the engine is mounted, and the degree of cooling required for the radiator 62 may be relatively low. Therefore, if one radiator fan is rotated at a relatively high rotation speed to cool the radiator 62, the degree of cooling of the radiator 62 becomes higher than necessary, and supercooling and waste of current consumption may easily occur. There is sex.

On the other hand, in this example, the control device 30 can control a plurality of fans 90A and 90B capable of blowing air to the radiator 62, and can more appropriately control the degree of cooling of the radiator 62 as described later. ..

It should be noted that three or more fans 90 capable of blowing air may be installed in one heat exchanger (radiator 62, oil cooler 70, condenser 82B). Hereinafter, the same applies to the second example described later.

Further, in this example, a dedicated fan 90 capable of blowing air to the heat exchanger is installed for each of the plurality of heat exchange devices.

As a result, the efficiency (cooling efficiency and heating efficiency) related to heat exchange can be improved as compared with the case where one fan 90 blows air to a plurality of heat exchange devices.

Further, in this example, a plurality of fans 90 capable of blowing air to the heat exchange devices are installed for each of the plurality of heat exchange devices.

As a result, the control device 30 is in a state where only some of the fans 90 are stopped or the rotation speed is relatively low according to the degree of heat exchange required for the heat exchange equipment for each of the plurality of heat exchange devices. It can be operated with.

The number of radiator fans may be one. The same may apply to the oil cooler fan and the condenser fan.

<Control processing related to the radiator fan of the control device>
Subsequently, the control process relating to the radiator fan of the control device 30 will be described with reference to FIGS. 7 and 8. In this example, when the radiator fan operates, the description will proceed on the assumption that it rotates at a relatively high rotation speed (for example, the maximum allowable rotation speed). Hereinafter, the same applies to the second example (FIGS. 14 and 15) described later.

7 and 8 are flowcharts schematically showing a first example of control processing related to the radiator fan by the control device 30 (controller 30A). This flowchart is repeatedly executed at predetermined control cycles, for example, during operation from the start (for example, ON of the key switch) to the stop (for example, OFF of the key switch) of the excavator. Hereinafter, the same may apply to the flowcharts of FIGS. 9 and 10, the flowchart of FIG. 11, the flowcharts of FIGS. 14 and 15, the flowcharts of FIGS. 16 and 17, and the flowchart of FIG.

As shown in FIG. 7, in step S102, the controller 30A determines whether or not the radiator fan (at least one of the fans 90A and 90B) is in operation. The controller 30A proceeds to step S104 when the radiator fans (both fans 90A and 90B) are not operating, and proceeds to step S110 when the radiator fan is operating.

In step S104, the controller 30A determines whether or not the temperature of at least one of the devices of the electric drive system to be cooled in the cooling circuit 60 exceeds the threshold value TDth11 based on the detection signal of the temperature sensor 54. The threshold value TDth 11 is, for example, a conforming value predetermined for each device of the electric drive system to be cooled in the cooling circuit 60. That is, the threshold values TDth11 for any two devices to be cooled in the cooling circuit 60 may be different from each other, and the controller 30A uses the value of the threshold TDth11 suitable for the devices to be cooled in the cooling circuit 60 for each device to be cooled. Then, the determination of this step is performed. Hereinafter, the same applies to the cases of the threshold values TDth12, TDth21, and TDth22 described later. The controller 30A proceeds to step S106 when the temperature of at least one of the devices of the electric drive system to be cooled in the cooling circuit 60 exceeds the threshold value TDth11, and ends the processing of the current flowchart when the temperature does not exceed the threshold value TDth11. do.

In step S106, the controller 30A determines whether or not the temperature of at least one of the devices of the electric drive system to be cooled by the cooling circuit 60 exceeds the threshold value TDth12 (> TDth11) based on the detection signal of the temperature sensor 54. .. The controller 30A proceeds to step S108 when the temperature of at least one of the devices of the electric drive system to be cooled in the cooling circuit 60 does not exceed the threshold value TDth12, and proceeds to step S114 when the temperature exceeds the threshold value TDth12.

In step S108, the controller 30A puts only one radiator fan into operation. Specifically, the controller 30A activates one of the fans 90A and 90B. One of the operations to be started may be the fan 90A or the fan 90B. As a result, the controller 30A starts the operation of one of the radiator fans in a situation where the temperature of the electric drive system device to be cooled by the cooling circuit 60 is relatively high, and increases the cooling degree of the radiator 62. Can be done. Therefore, the controller 30A can increase the degree of cooling of the refrigerant that flows through the radiator 62 and is cooled, and can lower the temperature of the equipment of the electric drive system.

When the process of step S108 is completed, the controller 30A completes the process of the current flowchart.

On the other hand, in step S110, the controller 30A determines whether or not there is only one radiator fan in operation. The controller 30A proceeds to step S112 when there is one radiator fan in operation, and proceeds to step S120 when there is not one (that is, both) radiator fans in operation.

In step S112, the controller 30A determines whether or not the temperature of at least one of the devices of the electric drive system to be cooled in the cooling circuit 60 exceeds the threshold value TDth12 based on the detection signal of the temperature sensor 54. The controller 30A proceeds to step S114 when the temperature of at least one of the devices of the electric drive system to be cooled in the cooling circuit 60 exceeds the threshold value TDth12, and proceeds to step S116 when the temperature does not exceed the threshold value TDth12.

In step S114, the controller 30A brings both radiator fans into operation. For example, when the determination condition in step S106 is satisfied (YES in step S106), the controller 30A outputs a control command to both the fans 90A and 90B to start the operation. Further, for example, when the determination condition of step S112 is satisfied (YES in step S112), the controller 30A outputs a control command to the other of the fans 90A and 90B, which is different from the operating one, and starts the operation. As a result, the controller 30A can drive both radiator fans in a situation where the temperature of the electric drive system device to be cooled by the cooling circuit 60 is very high, and the degree of cooling of the radiator 62 can be further increased. .. Therefore, the controller 30A can further increase the degree of cooling of the refrigerant that flows through the radiator 62 and is cooled, and can lower the temperature of the equipment of the electric drive system.

When the process of step S114 is completed, the controller 30A completes the process of the current flowchart.

On the other hand, in step S116, the controller 30A determines whether or not the temperature of all the electric drive system devices to be cooled by the cooling circuit 60 is equal to or lower than the threshold value TDth21 (≦ TDth11) based on the detection signal of the temperature sensor 54. judge. The controller 30A proceeds to step S118 when the temperatures of all the electric drive system devices to be cooled by the cooling circuit 60 are equal to or lower than the threshold value TDth21, and ends the processing of the current flowchart when the temperature is not equal to or lower than the threshold value TDth21.

In step S118, the controller 30A outputs a control command to one of the operating radiator fans and stops the controller 30A. That is, the controller 30A puts both radiator fans in a stopped state. As a result, the controller 30A can stop both radiator fans in accordance with the situation where the temperature of the electric drive system device to be cooled by the cooling circuit 60 has dropped to a very low state. Therefore, the controller 30A can suppress excessive cooling of the radiator 62, suppress unnecessary continuation of operation of the radiator fan, and suppress power consumption.

When the process of step S118 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, as shown in FIG. 8, in step S120, the controller 30A determines whether the temperatures of all the electric drive system devices to be cooled by the cooling circuit 60 are equal to or lower than the threshold value TDth22 based on the detection signal of the temperature sensor 54. The following is determined (TDth11 <TDth22≤TDth12). The controller 30A proceeds to step S122 when the temperatures of all the electric drive system devices to be cooled by the cooling circuit 60 are equal to or lower than the threshold value TDth22, and ends the processing of the current flowchart when the temperature is not equal to or lower than the threshold value TDth22.

In step S122, the controller 30A determines whether or not the temperature of all the electric drive system devices to be cooled by the cooling circuit 60 is equal to or less than the threshold value TDth21 based on the detection signal of the temperature sensor 54. The controller 30A proceeds to step S124 when the temperature of all the electric drive system devices to be cooled by the cooling circuit 60 is equal to or less than the threshold value TDth21, and proceeds to step S126 when the temperature is not equal to or less than TDth21.

In step S124, the controller 30A outputs a control command to both radiator fans and stops them. That is, the controller 30A puts both radiator fans in a stopped state. As a result, the same effect as in the case of step S120 is obtained.

When the process of step S124 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S126, the controller 30A outputs a control command to one of the radiator fans and stops the controller 30A. That is, the controller 30A is in a state where only one of the fans is operating. As a result, the controller 30A can stop one of the radiator fans in accordance with the situation where the temperature of the electric drive system device to be cooled by the cooling circuit 60 has dropped to a relatively low state. Therefore, the controller 30A can suppress excessive cooling of the radiator 62, suppress unnecessary continuation of operation of the radiator fan, and suppress power consumption.

The controller 30A changes the rotation speed of the radiator fan from a relatively low rotation speed to a relatively high rotation speed according to the temperature of the electric drive system device to be cooled by the cooling circuit 60. You may let me. For example, when the temperature of at least one of the devices of the electric drive system to be cooled by the cooling circuit 60 exceeds the threshold value TDth11, the controller 30A has a higher rotation speed as the amount exceeding the threshold value exceeds the threshold value TDth11. One radiator fan may be controlled so as to be. Then, when the temperature of at least one of the devices of the electric drive system to be cooled by the cooling circuit 60 exceeds the threshold value TDth11 and the excess amount exceeds a certain range, the controller 30A exceeds the threshold value. One radiator fan may be rotated at the maximum permissible rotation speed regardless of the amount of rotation. Further, for example, when the temperature of at least one of the devices of the electric drive system to be cooled in the cooling circuit 60 exceeds the threshold value TDth12, the controller 30A has a rotation speed as the amount exceeding the threshold value increases in a certain range. The other radiator fan may be controlled so that Then, when the temperature of at least one of the devices of the electric drive system to be cooled by the cooling circuit 60 exceeds the threshold value TDth12 and the excess amount exceeds a certain range, the controller 30A exceeds the threshold value. The other radiator fan may be rotated at the maximum permissible rotation speed regardless of the amount of rotation.

As described above, in this example, the plurality of radiator fans (fans 90A and 90B) are in a stopped state only in a part of the radiator fans under the control of the controller 30A, or the rotation speed is relative to that of the other radiator fans. It may be in a low operating condition.

As a result, the controller 30A can stop some of the radiator fans or operate them at a relatively low rotation speed according to the degree of cooling required for the radiator 62. Therefore, the controller 30A can suppress excessive cooling of the radiator 62 and can suppress power consumption due to the operation of the radiator fan.

Further, in this example, the controller 30A controls a plurality of radiator fans so that all the radiator fans operate at a relatively high rotation speed when the degree of cooling required for the radiator 62 is relatively high. On the other hand, the controller 30A has a plurality of radiator fans so that when the degree of cooling required for the radiator 62 is relatively low, only some of the radiator fans are stopped or the rotation speed is lower than that of the other fans. To control.

Specifically, when the temperature of the electric drive system equipment (an example of the equipment to be cooled) cooled by the refrigerant (an example of the fluid to be cooled) flowing inside the radiator 62 is relatively high, the controller 30A is used. Control multiple radiator fans so that they all operate at relatively high rotational speeds. On the other hand, in the controller 30A, when the temperature of the electric drive system device cooled by the refrigerant flowing inside the radiator 62 is relatively low, only a part of the radiator fans is stopped or the controller 30A is more than the other radiator fans. Control multiple radiator fans so that the rotation speed is relatively low.

As a result, the controller 30A can specifically stop a part of the plurality of radiator fans or operate the controller 30A in a state where the rotation speed is relatively low according to the degree of cooling required for the radiator 62. can.

<Control processing related to the oil cooler fan of the control device>
Subsequently, the control process relating to the oil cooler fan of the control device 30 will be described with reference to FIGS. 9 and 10. In this example, when the oil cooler fan operates, the description will proceed on the assumption that the fan rotates at a relatively high rotation speed (for example, the maximum allowable rotation speed). Hereinafter, the same applies to the second example (FIGS. 16 and 17) described later.

9 and 10 are flowcharts schematically showing a first example of control processing related to the oil cooler fan by the control device 30 (controller 30A).

As shown in FIG. 9, in step S202, the controller 30A determines whether or not the oil cooler fan (at least one of the fans 90C and 90D) is in operation. The controller 30A proceeds to step S204 when the oil cooler fan (both fans 90C and 90D) is not operating, and proceeds to step S210 when the oil cooler fan is operating.

In step S204, the controller 30A determines whether or not the hydraulic oil temperature exceeds the threshold value TORth11 based on the detection signal of the oil temperature sensor 56. The threshold value TORth11 is, for example, a predetermined conforming value. The same applies to the threshold values TORth12, TORth21, and TORth22, which will be described later. The controller 30A proceeds to step S206 when the hydraulic oil temperature exceeds the threshold value TORth11, and ends the processing of the current flowchart when the hydraulic oil temperature does not exceed the threshold value TORth11.

In step S206, the controller 30A determines whether or not the hydraulic oil temperature exceeds the threshold value TORth12 (> TORth11) based on the detection signal of the oil temperature sensor 56. The controller 30A proceeds to step S208 when the hydraulic oil temperature does not exceed the threshold value TORth12, and proceeds to step S214 when the hydraulic oil temperature exceeds the threshold value TORth12.

In step S208, the controller 30A puts only one oil cooler fan into operation. Specifically, the controller 30A activates one of the fans 90C and 90D. One of the operations to be started may be the fan 90C or the fan 90D. As a result, the controller 30A can start the operation of one of the oil cooler fans in a situation where the hydraulic oil temperature is relatively high, and can increase the degree of cooling of the oil cooler 70. Therefore, the controller 30A can increase the cooling degree of the hydraulic oil to be cooled by flowing through the oil cooler 70 and lower the temperature of the hydraulic oil.

When the process of step S208 is completed, the controller 30A completes the process of the current flowchart.

On the other hand, in step S210, the controller 30A determines whether or not there is only one oil cooler fan in operation. The controller 30A proceeds to step S212 when there is one operating oil cooler fan, and proceeds to step S220 when there is not one (that is, both) operating oil cooler fans.

In step S212, the controller 30A determines whether or not the hydraulic oil temperature exceeds the threshold value TORth12 based on the detection signal of the oil temperature sensor 56. The controller 30A proceeds to step S214 when the hydraulic oil temperature exceeds the threshold value TORth12, and proceeds to step S216 when the hydraulic oil temperature does not exceed the threshold value TORth12.

In step S214, the controller 30A brings both oil cooler fans into operation. For example, when the determination condition in step S206 is satisfied (YES in step S206), the controller 30A outputs a control command to both the fans 90C and 90D to start the operation. Further, for example, when the determination condition of step S212 is satisfied (YES in step S212), the controller 30A outputs a control command to the other of the fans 90C and 90D, which is different from the operating one, and starts the operation. As a result, the controller 30A can drive both oil cooler fans in a situation where the hydraulic oil temperature is very high, and can further increase the degree of cooling of the oil cooler 70. Therefore, the controller 30A can further increase the degree of cooling of the hydraulic oil that is cooled by passing through the oil cooler 70, and can lower the hydraulic oil temperature.

When the process of step S214 is completed, the controller 30A completes the process of the current flowchart.

On the other hand, in step S216, the controller 30A determines whether or not the hydraulic oil temperature is equal to or less than the threshold value TORth21 (≦ TORth11) based on the detection signal of the oil temperature sensor 56. The controller 30A proceeds to step S218 when the hydraulic oil temperature is equal to or less than the threshold value TORth21, and ends the processing of the current flowchart when the hydraulic oil temperature is not equal to or less than the threshold value TORth21.

In step S218, the controller 30A outputs a control command to one of the operating oil cooler fans and stops the controller 30A. That is, the controller 30A puts both oil cooler fans in a stopped state. As a result, the controller 30A can stop both oil cooler fans according to the situation where the hydraulic oil temperature has dropped to a very low state. Therefore, the controller 30A can suppress excessive cooling of the oil cooler 70, suppress unnecessary continuation of operation of the oil cooler fan, and suppress power consumption.

When the process of step S218 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, as shown in FIG. 10, in step S220, the controller 30A determines whether the hydraulic oil temperature is equal to or less than the threshold value TORth22 or less based on the detection signal of the oil temperature sensor 56 (TORth11 <TORth22 ≦ TORth12). The controller 30A proceeds to step S222 when the hydraulic oil temperature is equal to or less than the threshold value TORth22, and ends the processing of the current flowchart when the hydraulic oil temperature is not equal to or less than the threshold value TORth22.

In step S222, the controller 30A determines whether or not the temperature of all the electric drive system devices to be cooled by the cooling circuit 60 is equal to or less than the threshold value TORth21 based on the detection signal of the oil temperature sensor 56. The controller 30A proceeds to step S224 when the hydraulic oil temperature is TORth21 or less, and proceeds to step S226 when the hydraulic oil temperature is not TORth21 or less.

In step S224, the controller 30A outputs a control command to both oil cooler fans and stops them. That is, the controller 30A puts both oil cooler fans in a stopped state. As a result, the same effect as in the case of step S220 is obtained.

When the process of step S224 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S226, the controller 30A outputs a control command to one of the oil cooler fans and stops the controller 30A. That is, the controller 30A is in a state where only one of the fans is operating. As a result, the controller 30A can stop one of the oil cooler fans according to the situation where the hydraulic oil temperature has dropped to a relatively low state. Therefore, the controller 30A can suppress excessive cooling of the oil cooler 70, suppress unnecessary continuation of operation of the oil cooler fan, and suppress power consumption.

The controller 30A may change the rotation speed of the oil cooler fan from a relatively low rotation speed to a relatively high rotation speed according to the height of the hydraulic oil temperature. For example, the controller 30A may control one of the oil cooler fans so that when the hydraulic oil temperature exceeds the threshold value TORth11, the rotation speed increases in a certain range as the amount exceeding the threshold value increases. .. Then, when the hydraulic oil temperature exceeds the threshold value TORth11 and the excess amount exceeds a certain range, the controller 30A allows one oil cooler fan regardless of the excess amount. It may be rotated at the maximum rotation speed. Further, for example, when the hydraulic oil temperature exceeds the threshold value TORth12, the controller 30A controls the other oil cooler fan so that the rotation speed increases as the amount exceeding the threshold value increases in a certain range. It's okay. Then, when the hydraulic oil temperature exceeds the threshold value TORth12 and the excess amount exceeds a certain range, the controller 30A allows the other oil cooler fan regardless of the excess amount. It may be rotated at the maximum rotation speed.

As described above, in this example, the plurality of oil cooler fans (fans 90C, 90D) are in a stopped state only in a part of the oil cooler fans under the control of the controller 30A, or rotate more than other oil cooler fans. The speed may be relatively low.

As a result, the controller 30A can stop a part of the oil cooler fan or operate it at a relatively low rotation speed according to the degree of cooling required for the oil cooler 70. Therefore, the controller 30A can suppress excessive cooling of the oil cooler 70 and can suppress power consumption due to the operation of the oil cooler fan.

Further, in this example, the controller 30A controls a plurality of oil cooler fans so that all the oil cooler fans operate at a relatively high rotation speed when the degree of cooling required for the oil cooler 70 is relatively high. do. On the other hand, when the degree of cooling required for the oil cooler 70 is relatively low, the controller 30A has a plurality of oil cooler fans so that only some of the oil cooler fans are stopped or the rotation speed is lower than that of the other fans. Control the oil cooler fan.

Specifically, when the temperature (hydraulic oil temperature) of the hydraulic oil (an example of the fluid to be cooled) flowing through the inside of the oil cooler 70 is relatively high, all of the controllers 30A have a relatively high rotation speed. Control multiple oil cooler fans to operate. On the other hand, when the hydraulic oil temperature flowing through the inside of the oil cooler 70 is relatively low, the controller 30A has only a part of the oil cooler fans stopped or has a rotation speed relatively higher than that of the other oil cooler fans. Control multiple oil cooler fans so that they are in a low state.

As a result, the controller 30A specifically stops a part of the plurality of oil cooler fans or operates in a state where the rotation speed is relatively low according to the degree of cooling required for the oil cooler 70. be able to.

<Control processing related to the condenser fan of the control device>
Subsequently, the control process relating to the condenser fan of the control device 30 will be described with reference to FIG. In this example, when the radiator fan operates, the description will proceed on the assumption that it rotates at a relatively high rotation speed (for example, the maximum allowable rotation speed). Hereinafter, the same applies to the second example (FIG. 18) described later.

FIG. 11 is a flowchart schematically showing a first example of a control process relating to a condenser fan by the control device 30 (controller 30A).

As shown in FIG. 11, in step S302, the controller 30A determines whether or not the condenser fans (fans 90E and 90F) are in operation. The controller 30A proceeds to step S304 when the condenser fan is not in operation, and proceeds to step S308 when it is in operation.

In step S304, the controller 30A determines whether or not the compressor 82A has started operation. When the compressor 82A starts operating, the controller 30A proceeds to step S306, and when the compressor 82A is not operating, the controller 30A ends the processing of the current flowchart.

In step S306, the controller 30A outputs a control command to both condenser fans to start operation of both condenser fans.

When the process of step S306 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S308, the controller 30A determines whether or not the compressor 82A has stopped. When the compressor 82A is stopped, the controller 30A proceeds to step S310, and when the compressor 82A is not stopped, the controller 30A ends the processing of the current flowchart.

In step S310, the controller 30A outputs a control command to both condenser fans and stops both condenser fans.

When the process of step S310 is completed, the controller 30A ends the process of the current flowchart.

As described above, in this example, the controller 30A operates the condenser fan when the compressor 82A is operating, and stops the condenser fan when the compressor 82A is not operating.

As a result, the controller 30A can operate the condenser fan when the heat exchange in the condenser 82B is required, and stop the condenser fan when the heat exchange in the condenser 82B is not required. Therefore, the power consumption due to the operation of the condenser fan can be suppressed.

[Second example of fan control method]
Next, a second example of the control method of the fan 90 will be described with reference to FIGS. 12 to 18.

<Arrangement of heat exchange equipment and fans>
First, the arrangement of the heat exchange device and the fan 90 according to this example will be described.

12 and 13 are a front view and a side view showing a second example of the arrangement of the radiator 62, the oil cooler 70, the condenser 82B, and the fan 90. Hereinafter, for convenience, the arrangement relationship will be described using the directions in the figure (up, down, left, right, front, and back).

As shown in FIGS. 12 and 13, the radiator 62 and the oil cooler 70 are of the downflow type, respectively, as in the case of the first example (FIGS. 5 and 6) described above, and tanks are provided at both ends in the vertical direction. Be placed. The radiator 62 and the oil cooler 70 have a vertically long rectangular shape that is longer in the vertical direction than in the horizontal direction, and are arranged side by side.

The capacitor 82B has a horizontally long rectangular shape that is longer in the horizontal direction than in the vertical direction, as in the case of the first example described above. The condenser 82B is arranged adjacent to the front of the radiator 62 and the oil cooler 70, unlike the case of the first example described above. Specifically, the capacitor 82B is arranged so that its substantially left half covers the front of the substantially upper half of the heat exchange portion of the radiator 62, and its substantially right half is substantially the upper half of the heat exchange portion of the oil cooler 70. It is arranged so as to cover the front.

The fan 90 includes fans 90G to 90J.

The fans 90G and 90H are arranged behind the radiator 62, and blow air to the radiator 62 by sucking air from the front to the rear. The fans 90G and 90H are arranged side by side so that the fan 90G is on the upper side and the fan 90H is on the lower side. Hereinafter, the fans 90G and 90H may be collectively or individually referred to as "radiator fans".

The fans 90I and 90J are arranged behind the oil cooler 70, and blow air to the oil cooler 70 by sucking air from the front to the rear. The fans 90I and 90J are arranged side by side so that the fans 90C and 90C are on the upper side and the fans 90D are on the lower side. Hereinafter, the fans 90C and 90D may be collectively or individually referred to as "oil cooler fans".

As described above, the fan 90G is arranged behind the substantially upper half portion of the heat exchange portion of the radiator 62, that is, the portion where the front portion of the heat exchange portion of the radiator 62 is covered with the condenser 82B. Therefore, the fan 90G can blow air to both the condenser 82B and the radiator 62 by sucking air from the front to the rear.

As described above, the fan 90I is arranged behind the substantially upper half portion of the heat exchange portion of the oil cooler 70, that is, the portion where the front portion of the heat exchange portion of the oil cooler 70 is covered with the condenser 82B. Therefore, the fan 90I can blow air to both the condenser 82B and the radiator 62 by sucking air from the front to the rear.

Hereinafter, the fans 90G and 90I may be collectively or individually referred to as "condenser fans". Further, the fan 90G may be referred to as a "shared radiator fan", and the fan 90I may be referred to as a "shared oil cooler fan". Further, the fan 90H may be referred to as a "non-shared radiator fan", and the fan 90J may be referred to as a "non-shared oil cooler fan".

As described above, in this example, as in the case of the first example described above, a plurality of (two in this example) fans 90 capable of blowing air to one heat exchange device are installed. Further, in this example, as in the case of the first example described above, a plurality of fans 90 capable of blowing air to the heat exchange devices are installed for each of the plurality of heat exchange devices. As a result, the same actions and effects as in the case of the first example described above are obtained.

Further, in this example, the fans 90G and 90I are shared between the condenser 82B and the radiator 62 and the oil cooler 70, respectively. As a result, the number of installed fans 90 can be relatively reduced.

<Control processing related to the radiator fan of the control device>
Subsequently, the control process relating to the radiator fan of the control device 30 will be described with reference to FIGS. 14 and 15.

14 and 15 are flowcharts schematically showing a second example of control processing related to the radiator fan by the control device 30 (controller 30A). Hereinafter, the flag F1 indicates whether or not the operating conditions of the shared radiator fan (fan 90G) regarding the degree of cooling required for the radiator 62 are satisfied. The explanation of the flag F1 will proceed on the assumption that the initial state is "0" and the flag F1 is initialized to "0" when the excavator is started.

As shown in FIG. 14, in step S402, the controller 30A determines whether or not the non-shared radiator fan (fan 90H) is in operation. The controller 30A proceeds to step S404 when the non-shared radiator fan is not operating, and proceeds to step S410 when the non-shared radiator fan is operating.

Step S404 is the same as the process of step S104 of FIG. If the determination condition is satisfied, the controller 30A proceeds to step S406, and if the determination condition is not satisfied, the controller 30A ends the processing of the current flowchart.

Step S406 is the same as the process of step S106 of FIG. If the determination condition is not satisfied, the controller 30A proceeds to step S408, and if it is satisfied, the controller 30A proceeds to step S414.

In step S408, the controller 30A outputs a control command to the non-shared radiator fan, and starts operation of only the non-shared oil cooler fan. As a result, the controller 30A preferentially operates the shared radiator fan regardless of the degree of cooling required for the condenser 82B, and suppresses a situation in which the condenser 82B is supercooled or overheated. Can be done. Further, in the controller 30A, by preferentially operating the shared radiator fan, the air after passing through the condenser 82B is blown to the radiator 62, and as a result, the cooling degree of the radiator 62 is relatively lowered. It can be suppressed.

When the process of step S408 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S410, the controller 30A determines whether or not the flag F1 is "1", that is, whether or not the operating condition of the shared radiator fan regarding the degree of cooling required for the radiator 62 is satisfied. The controller 30A proceeds to step S412 when the flag F1 is not "1", and proceeds to step S420 when the flag F1 is "1".

Step S412 is the same as the process of step S112 of FIG. The controller 30A proceeds to step S414 if the determination condition is satisfied, and proceeds to step S416 if the determination condition is not satisfied.

In step S414, the controller 30A puts both radiator fans into operation and sets the flag F1 to "1". For example, when both radiator fans are stopped, the controller 30A outputs a control command to both radiator fans to start the operation, and sets the flag F1 to "1". When both radiator fans are stopped, the operating conditions of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B are not satisfied (that is, the flag F3 described later is "0"), and in step S406. Corresponds to the case where the judgment condition is satisfied. Further, for example, when only the shared radiator fan is operating, the controller 30A outputs a control command to the non-shared radiator fan to start the operation, and sets the flag F1 to "1". When only the shared radiator fan is operating, the operating conditions of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B are satisfied (that is, the flag F3 is "1"), and the determination in step S406 is performed. Corresponds to the case where the condition is satisfied. Further, for example, when only the non-shared radiator fan is operating, the controller 30A outputs a control command to the shared radiator fan to start the operation. When only the non-shared radiator fan is operating, the operating conditions of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B are not satisfied (that is, the flag F3 described later is "0"), and in step S412. Corresponds to the case where the judgment condition is satisfied. Further, the controller 30A only sets the flag F1 to "1" when both radiator fans are already in operation. When both radiator fans are already in operation, the operating conditions of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B are satisfied (that is, the flag F3 is "1"), and step S412 Corresponds to the case where the judgment condition of is satisfied.

When the process of step S414 is completed, the controller 30A ends the process of the current flowchart.

Step S416 is the same as the process of step S116 of FIG. If the determination condition is satisfied, the controller 30A proceeds to step S418, and if the determination condition is not satisfied, the controller 30A ends the processing of the current flowchart.

In step S418, the controller 30A outputs a control command to the non-shared radiator fan to stop the non-shared radiator fan.

When the process of step S418 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, as shown in FIG. 15, step S420 is the same as the process of step S120 in FIG. If the determination condition is satisfied, the controller 30A proceeds to step S422, and if the determination condition is not satisfied, the controller 30A ends the processing of the current flowchart.

Step S422 is the same as the process of step S122 of FIG. If the determination condition is satisfied, the controller 30A proceeds to step S424, and if not, the controller 30A proceeds to step S430.

In step S424, the controller 30A determines whether or not the flag F3 is "1", that is, whether or not the operating condition of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B is satisfied. The controller 30A proceeds to step S426 if the flag F3 is not "1", and proceeds to step S428 if the flag F3 is "1".

In step S426, the controller 30A outputs a control command to both radiator fans to stop them, and sets the flag F1 to "0".

When the process of step S426 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S428, the controller 30A outputs a control command to the non-shared radiator fan, stops the controller, and sets the flag F1 to "0". As a result, the controller 30A can continue the operation of the shared radiator fan even when the degree of cooling required for the radiator 62 is very low in the situation where the degree of heat exchange required for the capacitor 82B is relatively high. Can be done. Therefore, it is possible to suppress a situation in which the degree of heat exchange required for the condenser 82B is insufficient and the cooling performance and the heating performance of the air conditioner 80 are deteriorated.

When the process of step S428 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S430, the controller 30A determines whether or not the flag F3 is "1", that is, whether or not the operating condition of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B is satisfied. The controller 30A proceeds to step S432 when the flag F3 is not "1", and proceeds to step S434 when the flag F3 is "1".

In step S432, the controller 30A outputs a control command to the shared radiator fan, stops the controller, and sets the flag F1 to "0".

When the process of step S432 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S434, the controller 30A only performs the process of setting the flag F3 to "1". As a result, the controller 30A continues the operation of the shared radiator fan even when the degree of heat exchange required for the condenser 82B is relatively high and the degree of cooling required for the radiator 62 is relatively low. be able to. Therefore, it is possible to suppress a situation in which the degree of heat exchange required for the condenser 82B is insufficient and the cooling performance and the heating performance of the air conditioner 80 are deteriorated.

When the process of step S434 is completed, the controller 30A ends the process of the current flowchart.

As described above, in this example, the plurality of radiator fans include a shared radiator fan (an example of a shared fan) shared as a part of the plurality of condenser fans. When the degree of heat exchange required for the radiator 62 (an example of the first device) is relatively low, the controller 30A gives priority to non-shared radiator fans other than the shared radiator fan among the plurality of radiator fans. Make it work. On the other hand, when the degree of heat exchange required for the radiator 62 is relatively high, the controller 30A operates the shared radiator fan in addition to the non-shared radiator fan.

As a result, the controller 30A can suppress the influence on the degree of heat exchange of the condenser 82B, which may occur when operating the radiator fan, based on the degree of cooling required for the radiator 62.

Further, in this example, the controller 30A is a case where the condition for stopping the shared radiator fan based on the degree of heat exchange (cooling degree) required for the radiator 62 is satisfied while the shared radiator fan is operating. Even if there is, if the condition for stopping the shared fan based on the degree of heat exchange required for the condenser 82B (an example of the second device) is not satisfied, the operation of the shared radiator fan is continued.

As a result, the controller 30A can suppress a situation in which the degree of heat exchange in the condenser 82B is insufficient and the air conditioning performance of the air conditioner 80 is affected.

The radiator 62, the condenser 82B, and the fan 90 may be arranged so that all of the plurality of condenser fans become shared radiator fans. Also in this case, the controller 30A achieves the same operation and effect by adopting the same control method.

<Control processing related to the oil cooler fan of the control device>
Subsequently, the control process relating to the oil cooler fan of the control device 30 will be described with reference to FIGS. 16 and 17.

16 and 17 are flowcharts schematically showing a second example of control processing related to the oil cooler fan by the control device 30 (controller 30A). Hereinafter, the flag F2 indicates whether or not the operating conditions of the shared oil cooler fan (fan 90I) regarding the degree of cooling required for the oil cooler 70 are satisfied. The explanation of the flag F2 will proceed on the assumption that the initial state is "0" and the flag F2 is initialized to "0" when the excavator is started.

As shown in FIG. 16, in step S502, the controller 30A determines whether or not the non-shared oil cooler fan (fan 90J) is in operation. The controller 30A proceeds to step S504 when the non-shared oil cooler fan is not operating, and proceeds to step S510 when the non-shared oil cooler fan is operating.

Step S504 is the same as the process of step S204 of FIG. If the determination condition is satisfied, the controller 30A proceeds to step S506, and if the determination condition is not satisfied, the controller 30A ends the processing of the current flowchart.

Step S506 is the same as the process of step S206 of FIG. If the determination condition is not satisfied, the controller 30A proceeds to step S508, and if it is satisfied, the controller 30A proceeds to step S514.

In step S508, the controller 30A outputs a control command to the non-shared oil cooler fan, and starts operation of only the non-shared oil cooler fan. As a result, the controller 30A preferentially operates the shared oil cooler fan regardless of the degree of cooling required for the condenser 82B, and suppresses a situation in which the condenser 82B is overcooled or overheated. be able to. Further, in the controller 30A, by preferentially operating the shared oil cooler fan, the air after passing through the condenser 82B is blown to the oil cooler 70A, and as a result, the cooling degree of the oil cooler 70A is relatively lowered. It is possible to suppress the situation where it ends up.

When the process of step S508 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S510, the controller 30A determines whether or not the flag F2 is "1", that is, whether or not the operating conditions of the shared oil cooler fan regarding the degree of cooling required for the oil cooler 70 are satisfied. do. The controller 30A proceeds to step S512 if the flag F2 is not "1", and proceeds to step S520 if the flag F2 is "1".

Step S512 is the same as the process of step S212 of FIG. The controller 30A proceeds to step S514 if the determination condition is satisfied, and proceeds to step S516 if the determination condition is not satisfied.

In step S514, the controller 30A sets both oil cooler fans to operate and sets the flag F2 to "1". For example, when both oil cooler fans are stopped, the controller 30A outputs a control command to both oil cooler fans to start the operation, and sets the flag F2 to "1". When both oil cooler fans are stopped, the operating conditions of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B are not satisfied (that is, the flag F3 described later is "0"), and step S506 Corresponds to the case where the judgment condition of is satisfied. Further, for example, when only the shared oil cooler fan is operating, the controller 30A outputs a control command to the non-shared oil cooler fan to start the operation, and sets the flag F2 to "1". When only the shared oil cooler fan is operating, the operating conditions of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B are satisfied (that is, the flag F3 is "1"), and step S506 is performed. Corresponds to the case where the judgment condition is satisfied. Further, for example, when only the non-shared oil cooler fan is operating, the controller 30A outputs a control command to the shared oil cooler fan to start the operation. When only the non-shared oil cooler fan is operating, the operating conditions of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B are not satisfied (that is, the flag F3 described later is "0"), and step S512. Corresponds to the case where the judgment condition of is satisfied. Further, the controller 30A only sets the flag F2 to "1" when both oil cooler fans are already in operation. If both oil cooler fans are already in operation, the operating conditions for the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B are met (ie, flag F3 is "1") and step. This corresponds to the case where the determination condition of S512 is satisfied.

When the process of step S514 is completed, the controller 30A ends the process of the current flowchart.

Step S516 is the same as the process of step S216 of FIG. If the determination condition is satisfied, the controller 30A proceeds to step S518, and if the determination condition is not satisfied, the controller 30A ends the processing of the current flowchart.

In step S518, the controller 30A outputs a control command to the non-shared oil cooler fan to stop the non-shared oil cooler fan.

When the process of step S518 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, as shown in FIG. 17, step S520 is the same as the process of step S220 in FIG. If the determination condition is satisfied, the controller 30A proceeds to step S522, and if the determination condition is not satisfied, the controller 30A ends the processing of the current flowchart.

Step S522 is the same as the process of step S222 of FIG. The controller 30A proceeds to step S524 if the determination condition is satisfied, and proceeds to step S530 if the determination condition is not satisfied.

In step S524, the controller 30A determines whether or not the flag F3 is "1", that is, whether or not the operating condition of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B is satisfied. The controller 30A proceeds to step S526 if the flag F3 is not "1", and proceeds to step S528 if the flag F3 is "1".

In step S526, the controller 30A outputs a control command to both oil cooler fans to stop them, and sets the flag F2 to "0".

When the process of step S526 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S528, the controller 30A outputs a control command to the non-shared oil cooler fan to stop the controller 30A, and sets the flag F2 to "0". As a result, the controller 30A continues to operate the shared oil cooler fan even when the degree of heat exchange required for the condenser 82B is relatively high and the degree of cooling required for the oil cooler 70 is very low. Can be made to. Therefore, it is possible to suppress a situation in which the degree of heat exchange required for the condenser 82B is insufficient and the cooling performance and the heating performance of the air conditioner 80 are deteriorated.

When the process of step S528 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S530, the controller 30A determines whether or not the flag F3 is "1", that is, whether or not the operating condition of the shared oil cooler fan regarding the degree of heat exchange required for the condenser 82B is satisfied. The controller 30A proceeds to step S532 when the flag F3 is not "1", and proceeds to step S534 when the flag F3 is "1".

In step S532, the controller 30A outputs a control command to the shared oil cooler fan to stop the controller 30A, and sets the flag F2 to "0".

When the process of step S532 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S534, the controller 30A only performs the process of setting the flag F3 to "1". As a result, the controller 30A operates the shared oil cooler fan even when the degree of heat exchange required for the condenser 82B is relatively high and the degree of cooling required for the oil cooler 70 is relatively low. Can be continued. Therefore, it is possible to suppress a situation in which the degree of heat exchange required for the condenser 82B is insufficient and the cooling performance and the heating performance of the air conditioner 80 are deteriorated.

When the process of step S534 is completed, the controller 30A ends the process of the current flowchart.

As described above, in this example, the plurality of oil cooler fans include a shared oil cooler fan (an example of a shared fan) shared as a part of the plurality of condenser fans. When the degree of heat exchange required for the oil cooler 70 (an example of the first device) is relatively low, the controller 30A is a non-shared oil cooler fan other than the shared oil cooler fan among the plurality of oil cooler fans. To operate preferentially. On the other hand, when the degree of heat exchange required for the oil cooler 70 is relatively high, the controller 30A operates the shared oil cooler fan in addition to the non-shared oil cooler fan.

As a result, the controller 30A can suppress the influence on the degree of heat exchange of the condenser 82B, which may occur when the oil cooler fan is operated, based on the degree of cooling required for the oil cooler 70.

Further, in this example, in the controller 30A, a condition for stopping the shared oil cooler fan based on the degree of heat exchange (cooling degree) required for the oil cooler 70 is satisfied while the shared oil cooler fan is operating. Even if there is, if the condition for stopping the shared oil cooler fan based on the degree of heat exchange required for the condenser 82B is not satisfied, the operation of the shared oil cooler fan is continued.

As a result, the controller 30A can suppress a situation in which the degree of heat exchange in the condenser 82B is insufficient and the air conditioning performance of the air conditioner 80 is affected.

The oil cooler 70, the condenser 82B, and the fan 90 may be arranged so that all of the plurality of condenser fans are shared oil cooler fans. Also in this case, the controller 30A achieves the same operation and effect by adopting the same control method.

<Control processing related to capacitors in control devices>
Subsequently, the control process relating to the condenser fan of the control device 30 will be described with reference to FIG.

FIG. 18 is a flowchart schematically showing a second example of the control process relating to the condenser fan by the control device 30 (controller 30A). Hereinafter, the flag F3 indicates whether or not the operating conditions of the condenser fans (fan 90G, fan 90I) regarding the degree of heat exchange required for the condenser 82B are satisfied. The explanation of the flag F3 will proceed on the assumption that the initial state is "0" and the flag F3 is initialized to "0" when the excavator is started.

As shown in FIG. 18, in step S602, the controller 30A determines whether or not the flag F3 is "1", that is, whether or not the operating condition of the capacitor fan is satisfied based on the degree of heat exchange required for the capacitor 82B. To judge. The controller 30A proceeds to step S604 if the flag F3 is not "1", and proceeds to step S608 if the flag F3 is "1".

Step S604 is the same process as step S304 of FIG. If the determination condition is satisfied, the controller 30A proceeds to step S606, and if the determination condition is not satisfied, the controller 30A ends the processing of the current flowchart.

In step S606, the controller 30A sets both condenser fans to operate and sets the flag F3 to "1". For example, when both condenser fans are stopped, the controller 30A outputs a control command to both condenser fans to start the operation, and sets the flag F3 to "1". When both condenser fans are stopped, both the operating conditions of the shared radiator fan based on the cooling degree required for the radiator 62 and the operating conditions of the shared oil cooler based on the cooling degree required for the oil cooler 70 are not satisfied ( That is, it corresponds to the case where the flags F1 and F2 are both "0"). Further, for example, when only the shared radiator fan is operating, the controller 30A outputs a control command to the shared oil cooler fan to start the operation, and sets the flag F3 to "1". When only the shared radiator fan is operating, the operating condition of the shared radiator fan based on the cooling degree required for the radiator 62 is satisfied (that is, the flag F1 is "1"), and the cooling degree required for the oil cooler 70 is satisfied. It corresponds to the case where the operating condition of the shared oil cooler based on the above is not satisfied (that is, both flags F2 are "0"). Further, for example, when only the shared oil cooler fan is operating, the controller 30A outputs a control command to the shared radiator fan to start the operation, and sets the flag F3 to "1". When only the shared oil cooler fan is operating, the operating conditions of the shared radiator fan based on the cooling degree required for the radiator 62 are not satisfied (that is, the flag F1 is "0"), and the cooling degree required for the oil cooler 70 is not satisfied. It corresponds to the case where the operating condition of the shared oil cooler based on the above is satisfied (that is, the flag F2 is "1"). Further, the controller 30A only performs a process of setting the flag F3 to "1" when, for example, both condenser fans are already in operation. If both condenser fans are already in operation, both the operating conditions of the shared radiator fan based on the cooling degree required for the radiator 62 and the operating conditions of the shared oil cooler based on the cooling degree required for the oil cooler 70 are satisfied. (That is, it corresponds to the case where the flags F1 and F2 are both "0").

When the process of step S606 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, step S608 is the same process as step S308 in FIG. If the determination condition is satisfied, the controller 30A proceeds to step S610, and if the determination condition is not satisfied, the controller 30A ends the processing of the current flowchart.

In step S610, the controller 30A determines whether or not both the flags F1 and F2 are "0". That is, whether or not the controller 30A is in a state in which both the operating condition of the shared radiator fan based on the cooling degree required for the radiator 62 and the operating condition of the shared oil cooler based on the cooling degree required for the oil cooler 70 are not satisfied. To judge. The controller 30A proceeds to step S612 when the flags F1 and F2 are both "0", and proceeds to step S614 when at least one of the flags F1 and F2 is not "0" (that is, "1").

In step S612, the controller 30A outputs a control command to both condenser fans to stop them, and sets the flag F3 to "0".

When the process of step S612 is completed, the controller 30A ends the current flowchart.

On the other hand, in step S614, the controller 30A determines whether or not the flag F1 is "0". The controller 30A proceeds to step S616 when the flag F1 is "0", and proceeds to step S618 when the flag F1 is not "0" (that is, "1").

In step S616, the controller 30A outputs a control command to the shared radiator fan, stops the controller, and sets the flag F3 to "0". As a result, the controller 30A operates the shared oil cooler fan under the condition that the degree of heat exchange required for the condenser 82B is relatively low, but the degree of cooling required for the oil cooler 70 is very high. Can be continued.

When the process of step S616 is completed, the controller 30A ends the current flowchart.

On the other hand, in step S618, the controller 30A determines whether or not the flag F2 is "0". The controller 30A proceeds to step S620 when the flag F2 is "0", and proceeds to step S622 when the flag F2 is not "0" (that is, both the flags F1 and F2 are "1").

In step S620, the controller 30A outputs a control command to the shared oil cooler fan to stop the controller 30A, and sets the flag F3 to "0". As a result, the controller 30A continues the operation of the shared radiator fan even in a situation where the degree of heat exchange required for the condenser 82B is relatively low, but in a situation where the degree of cooling required for the radiator 62 is very high. be able to.

When the process of step S620 is completed, the controller 30A ends the process of the current flowchart.

On the other hand, in step S622, the controller 30A only performs a process of setting the flag F3 to "0". As a result, the controller 30A can use the shared radiator fan and the controller 30A even when the degree of heat exchange required for the condenser 82B is relatively low, but when the degree of cooling required for the radiator 62 and the oil cooler 70 is very high. The operation of the shared oil cooler fan can be continued.

When the process of step S622 is completed, the controller 30A ends the process of the current flowchart.

As described above, in this example, the controller 30A is a case where the condition for stopping the shared radiator fan based on the degree of heat exchange required for the capacitor 82B is satisfied while the shared radiator fan is operating. However, if the condition for stopping the shared radiator fan based on the degree of heat exchange (cooling degree) required for the radiator 62 is not satisfied, the operation of the shared radiator fan is continued.

As a result, the controller 30A can suppress a situation in which the degree of cooling in the radiator 62 is insufficient and the cooling performance of the cooling circuit 60 is affected.

Further, in this example, the controller 30A is a case where the condition for stopping the shared oil cooler fan based on the degree of heat exchange required for the condenser 82B is satisfied while the shared oil cooler fan is operating. However, if the condition for stopping the shared oil cooler fan based on the degree of heat exchange (cooling degree) required for the oil cooler 70 is not satisfied, the operation of the shared oil cooler fan is continued.

As a result, the controller 30A can suppress a situation in which the degree of cooling in the oil cooler 70 is insufficient and the cooling performance of the hydraulic oil is affected.

[Third example of fan control method]
Next, a third example of the fan control method will be described.

In this example, the control device 30 (controller 30A) limits the operation of the operating fan 90 according to the intention of the operator while the fan 90 is operating.

For example, when a predetermined input is made through the input device 52 while the fan 90 is in operation, the controller 30A temporarily (for example, a predetermined fixed time) causes the operating fan 90 regardless of other conditions. Only) may be stopped.

Further, when a predetermined input is performed through the input device 52 while the fan 90 is in operation, the controller 30A temporarily puts the operating fan 90 in a relatively low rotation speed regardless of other conditions. You may limit it.

Further, the controller 30A may stop all of the plurality of fans 90 that can blow air to one heat exchange device, or set the rotation speed to a low state, or set only a part of them in the stopped state. Alternatively, the rotation speed may be set to a low level.

As described above, in this example, when a predetermined input is received by the input device 52, the controller 30A shifts a part or all of the plurality of fans to a stopped state or a state in which the rotation speed is relatively low.

As a result, the operator makes a predetermined input through the input device 52, for example, in a situation where the operating sound of the operating fan 90 hinders communication with surrounding workers. Can be reduced and communication with surrounding workers can be achieved.

[Transform / Change]
Although the embodiments have been described in detail above, the present disclosure is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist described in the claims.

For example, in the above-described embodiment, the configuration of the heat exchange device and the fan mounted on the excavator not equipped with the engine and the control method of the fan have been described, but the same configuration and the control method can be applied to the excavator on which the engine is mounted. May be applied. Specifically, the same configuration and control method as those in the above-described embodiment may be applied to the configuration of the radiator of the cooling circuit that cools the engine, the configuration of the fan that cools the radiator, and the control method of the fan. ..

Further, in the above-described embodiments and modifications, the configurations of the heat exchanger and the fan mounted on the excavator and the control method of the fan have been described, but the same configuration and control method include the heat exchanger and the fan. It may be applied to other working machines. Other work machines include, for example, industrial vehicles, forklifts, cranes, bulldozers and the like.

1 Lower traveling body 1A, 1B Traveling hydraulic motor (hydraulic actuator)
3 Upper swing body 4 Boom 5 Arm 6 Bucket 7 Boom cylinder (flood actuator)
8 Arm cylinder (hydraulic actuator)
9 Bucket cylinder (hydraulic actuator)
12 Pump motor (motor)
14 Main pump (hydraulic pump)
15 Pilot pump 18 Inverter unit 18A Inverter 18B Inverter 19 Power storage device 26 Operating device 30 Control device 30A to 30C controller 44 DC-DC converter 46 Battery 50 Output device 52 Input device 54 Temperature sensor 56 Oil temperature sensor 60 Cooling circuit 62 Radiator (predetermined) Equipment, first equipment)
64 Water pump 70 Oil cooler (predetermined equipment, first equipment)
80 Air conditioner 82 Heat pump cycle 82A Compressor 82B Condenser (predetermined equipment, second equipment)
82C Expansion valve 82D Evaporator 90, 90A-90J Fan

Claims (10)

Equipped with multiple fans capable of blowing heat to a given device that exchanges heat with the outside air,
Excavator. Of the plurality of fans, only some of them may be stopped or may be in an operating state where the rotation speed is lower than that of the other fans.
The excavator according to claim 1. When the degree of heat exchange required for the predetermined device is relatively high, the plurality of fans are controlled so as to have a relatively high rotation speed, and the degree of heat exchange required for the predetermined device is achieved. When is relatively low, the plurality of fans are controlled so that only a part of the plurality of fans is stopped or the rotation speed is lower than that of the other fans.
The excavator according to claim 1 or 2. When the temperature of the fluid to be cooled that flows through the inside of the predetermined device or the device to be cooled that is cooled through the fluid to be cooled is relatively high, the plurality of fans so as to have a relatively high rotation speed. When the temperature is relatively low, the plurality of fans are set so that only a part of the fans is stopped or the rotation speed is lower than that of the other fans. Control,
The excavator according to claim 3. There are a plurality of the predetermined devices.
The excavator according to any one of claims 1 to 4. The plurality of predetermined devices include at least a radiator of a cooling circuit for cooling the device of the electric drive system, an oil cooler for cooling the hydraulic oil supplied to the hydraulic actuator, and a capacitor included in the air conditioner for air-conditioning the cabin. Including two
The excavator according to claim 5. The plurality of predetermined devices include a first device and a second device.
The plurality of fans corresponding to the first device include, in a part thereof, a shared fan shared as a part or all of the plurality of fans corresponding to the second device.
When the degree of heat exchange required for the first device is relatively low, the fans other than the shared fan among the plurality of fans corresponding to the first device are preferentially operated, and the first device is operated. When the degree of heat exchange required for one device is relatively high, the shared fan is operated in addition to the fans other than the shared fan among the plurality of fans corresponding to the first device.
The excavator according to claim 5 or 6. Even if the condition for stopping the shared fan based on the degree of heat exchange required for the first device is satisfied while the shared fan is operating, the second device can be used. If the condition for stopping the shared fan based on the required degree of heat exchange is not satisfied, the operation of the shared fan is continued.
The excavator according to claim 7. Equipped with an input device that accepts input
When a predetermined input is received by the input device, a part or all of the plurality of fans is shifted to a stopped state or a state in which the rotation speed is relatively low.
The excavator according to any one of claims 1 to 8. With hydraulic actuator,
A hydraulic pump for supplying hydraulic oil to the hydraulic actuator and
The electric motor for driving the hydraulic pump is provided.
The excavator according to any one of claims 1 to 9.

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