Cooling system for electric construction machine, and electric construction machine including same

Abstract

Provided is a cooling system for an electric construction machine which comprises an electric pump device that is driven by electric power supplied from a battery. The cooling system includes a plurality of cooling instruments that respectively cool a plurality of objects to be cooled including the battery and the electric pump device. The plurality of cooling instruments include at least one first cooling instrument and at least one second cooling instrument. The first cooling instrument and the second cooling instrument are arranged on one side in a first direction and on the other side in the first direction with the battery interposed therebetween.

Description

Cooling system for electric construction machine and electric construction machine equipped with same

[0001] The present disclosure relates to a cooling system for an electric construction machine equipped with an electric pump device driven by power supplied from a battery, and to an electric construction machine equipped with the same.

[0002] A construction machine is equipped with a plurality of cooling system devices such as a radiator and a coolant for a hydraulic fluid to cool objects to be cooled such as hydraulic oil. For example, a shovel disclosed in Patent Document 1 is known as such a construction machine.

[0003] Japanese Patent Application Laid-Open No. 2021-63339

[0004] The excavator in Patent Document 1 is an electric excavator that has a battery storage compartment in the rear of the rotating body. Also, a main storage compartment is formed in the rotating body to the front right of the battery storage compartment, and all of the heat exchangers, which are cooling system equipment, are housed in the main storage compartment. Therefore, it is conceivable that the weight balance of the electric excavator will be biased to the right.

[0005] Therefore, an object of the present disclosure is to provide a cooling system that can improve the weight balance of an electric construction machine.

[0006] The cooling system for an electric construction machine disclosed herein is a cooling system for an electric construction machine equipped with an electric pump device driven by power supplied from a battery, and is equipped with a plurality of cooling system devices that cool a plurality of cooling objects including the battery and the electric pump device, respectively, and the plurality of cooling system devices include at least one first cooling system device and at least one second cooling system device, and the first cooling system device and the second cooling system device are respectively arranged on one side of the battery in a first direction and on the other side of the first direction.

[0007] According to the present disclosure, the first cooling system device and the second cooling system device are disposed on one side of the battery in the first direction and the other side of the battery in the first direction, respectively. This prevents the cooling system devices from being disposed biased to one side of the battery in the first direction. This improves the weight balance of the electric construction machine in the first direction.

[0008] The electric construction machine of the present disclosure comprises the cooling system of the electric construction machine described above, a traveling device, a rotating body rotatably mounted on the traveling device, a boom swingably mounted on the rotating body, the battery, and the electric pump device driven by power supplied from the battery, wherein the rotating body has the cabin, the electric pump device is arranged on one side in a first direction within the rotating body, the cabin is arranged on the opposite side of the electric pump device across the boom, and the battery is arranged on one side in a second direction perpendicular to the first direction with respect to the electric pump device and the cabin.

[0009] According to the above configuration, the electric pump unit is disposed on one side in a first direction within the rotating body. The cabin is disposed on the opposite side of the boom from the electric pump unit. The battery is disposed on one side in a second direction perpendicular to the first direction relative to the electric pump unit and the cabin. The hydraulic fluid coolant, the capacitor, the inverter radiator, and the battery radiator are disposed on both sides of the battery in the first direction. This improves the weight balance of the electric construction machine.

[0010] According to the present disclosure, the weight balance of an electric construction machine can be improved.

[0011] The above and other objects, features, and advantages of the present disclosure will become apparent from the following detailed description of preferred embodiments, which proceeds with reference to the accompanying drawings.

[0012] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, and are not intended to be limiting of the invention, as claimed.

[0013] A cooling system 1 according to an embodiment of the present disclosure and an electric construction machine 2 equipped with the same will be described below with reference to the drawings. Note that the concepts of directions used in the following description are used for convenience of explanation and do not limit the orientation of the configuration of the present disclosure to those directions. Furthermore, the cooling system 1 and electric construction machine 2 described below are merely one embodiment of the present disclosure. Therefore, the present disclosure is not limited to the embodiment, and additions, deletions, and modifications are possible within the scope of the spirit of the present disclosure.

[0014] [Construction Machine] The electric construction machine 2 shown in FIG. 1 performs various tasks by moving an attachment. The electric construction machine 2 is, for example, an electric shovel (hereinafter simply referred to as "shovel"). However, the electric construction machine 2 is not limited to a shovel, and may be a crane, a wheel loader, or the like. The shovel 2 includes a traveling device 11, a revolving body 12, a boom 13, an arm 14, and a bucket 15. The traveling device 11 includes, for example, a pair of crawlers 11L, 11R. Each of the crawlers 11L, 11R can be driven to move in various directions. The revolving body 12 is attached to the traveling device 11 so as to be rotatable about a rotation axis extending in the vertical direction. The boom 13 is attached to the revolving body 12 so as to be swingable in the vertical direction. The arm 14 is attached to the tip of the boom 13 so as to be swingable in the front-rear direction. Furthermore, the bucket 15 is attached to the tip of the arm 14 so as to be swingable in the front-rear direction or the up-down direction. The front-rear direction is, for example, the direction in which the boom 13 extends.

[0015] The traveling unit 11, the revolving unit 12, the boom 13, the arm 14, and the bucket 15 are each provided with a hydraulic actuator, such as a hydraulic motor and a cylinder. That is, each of the crawlers 11L, 11R of the traveling unit 11 is provided with a traveling hydraulic motor (not shown). The traveling motor drives the crawlers 11L, 11R by supplying hydraulic fluid. This allows the traveling unit 11 to move in various directions. The hydraulic fluid is, for example, a liquid such as oil. The revolving unit 12 is provided with a swing hydraulic motor (not shown). The swing hydraulic motor swings the revolving unit 12 by supplying hydraulic fluid. The boom 13 is provided with a boom cylinder 13a. The arm 14 and the bucket 15 are each provided with an arm cylinder and a bucket cylinder (not shown). The boom cylinder 13a, the arm cylinder, and the bucket cylinder are supplied with hydraulic fluid to swing the boom 13, the arm 14, and the bucket 15, respectively. The excavator 2 also includes a hydraulic drive system 3 and a cooling system 1.

[0016] [Hydraulic Drive System] The hydraulic drive system 3 is disposed within the revolving bed 12 as shown in FIG. 2. The hydraulic drive system 3 supplies hydraulic fluid to each of the hydraulic actuators described above to operate each of the hydraulic actuators. The hydraulic drive system 3 also controls the movement of each of the hydraulic actuators by controlling the flow (flow rate and flow direction) of hydraulic fluid supplied to each of the hydraulic actuators. The hydraulic drive system 3 configured in this manner includes a tank 21, an electric pump device 22, and a battery 23 as shown in FIG. 2. In more detail, the hydraulic drive system 3 further includes a multi-control valve 24.

[0017] [Tank] The tank 21 stores hydraulic fluid discharged from the electric pump device 22, which will be described in detail later. The hydraulic fluid in the tank 21 is sucked into the electric pump device 22, discharged, and then supplied to each hydraulic actuator via the multi-control valve 24. The hydraulic fluid is also returned from each hydraulic actuator to the tank 21 via the multi-control valve 24. The tank 21 is disposed on the right side (i.e., one side in the first direction) in the left-right direction, which is an example of a first direction, within the revolving unit 12. More specifically, the revolving unit 12 has a cabin 12a in which a driver (or operator) can ride. As described above, the revolving unit 12 is provided with a boom 13. In this embodiment, the boom 13 is disposed on one side (front side in this embodiment) in a second direction perpendicular to the first direction of the revolving unit 12, in a middle portion in the left-right direction. The cabin 12a is disposed on the front left side (i.e., the other side in the first direction) of the revolving unit 12, adjacent to the boom 13. The tank 21 is disposed on the opposite side of the cabin 12a across the boom 13. That is, the tank 21 is disposed on the front right side of the rotating unit 12 so as to be adjacent to the boom 13.

[0018] [Electric Pump Device] The electric pump device 22 is an electric hydraulic pump device mounted on the excavator 2. The electric pump device 22 is disposed adjacent to the tank 21 within the revolving body 12. More specifically, the electric pump device 22 is provided rearward of the tank 21. That is, the electric pump device 22 is disposed on the right side within the revolving body 12. The electric pump device 22 is electrically connected to the battery 23. The electric pump device 22 is further connected to the tank 21 via a suction pipe 22a and to the multi-control valve 24 via a discharge pipe 22b. The electric pump device 22 is driven by current supplied from the battery 23. When driven, the electric pump device 22 draws in hydraulic fluid from the tank 21 via the suction pipe 22a. When driven, the electric pump device 22 discharges hydraulic fluid to the multi-control valve 24 via the discharge pipe 22b.

[0019] More specifically, the electric pump device 22 includes a hydraulic pump 31 and an electric motor 32. The electric pump device 22 is a so-called vertically mounted electric pump device. That is, in the electric pump device 22, the hydraulic pump 31 and the electric motor 32 are mounted on a frame 33 so as to be aligned in the vertical direction, which is an example of a third direction. The third direction is a direction perpendicular to the first and second directions.

[0020] The hydraulic pump 31 discharges hydraulic fluid when rotated. In this embodiment, the hydraulic pump 31 is a tandem pump consisting of two swash plate pumps. However, the hydraulic pump 31 is not limited to a tandem pump and may be a single pump. Furthermore, the hydraulic pump 31 is not limited to a swash plate pump and may be a bent-axis pump, a gear pump, or the like. The hydraulic pump 31 is connected to the tank 21 via the suction pipe 22a and to the multi-control valve 24 via the discharge pipe 22b.

[0021] The electric motor 32 drives the hydraulic pump 31 to rotate, thereby discharging hydraulic fluid from the hydraulic pump 31. The electric motor 32 is, for example, a three-phase AC motor. However, the electric motor 32 may also be a DC motor. The electric motor 32 is, for example, formed in a cylindrical shape and arranged on the same axis as the hydraulic pump 31. However, the electric motor 32 does not necessarily have to be aligned in a straight line with the hydraulic pump 31, and the electric motor 32 may be arranged parallel to but with their axes offset from each other, or the axis of the electric motor 32 may be arranged so as to intersect the hydraulic pump 31 at an angle or at a right angle.

[0022] The electric pump device 22 further includes an inverter 34. The inverter 34 converts direct current into alternating current. The inverter 34 is electrically connected to the battery 23 and the electric motor 32, which will be described later. The inverter 34 converts the direct current supplied from the battery 23 into alternating current and supplies the alternating current to the electric motor 32. This causes the electric motor 32 to rotate and drive the hydraulic pump 31. The inverter 34 is provided, for example, integrally with the electric motor 32. In this embodiment, the inverter 34 is provided on the electric motor 32 so as to be located on the opposite side of the hydraulic pump 31 in the up-down direction.

[0023] [Multi-Control Valve] The multi-control valve 24 supplies the hydraulic fluid discharged from the electric pump device 22 to each of the hydraulic actuators and controls the flow of the supplied hydraulic fluid. Explaining in more detail, as described above, the multi-control valve 24 is connected to the hydraulic pump 31 of the electric pump device 22 via the discharge pipe 22b. The multi-control valve 24 configured in this manner is located behind the boom 13 within the revolving unit 12. In this embodiment, the multi-control valve 24 is located adjacent to the electric pump device 22 within the revolving unit 12.

[0024] [Battery] The battery 23 is electrically connected to the electric pump device 22 (more specifically, the inverter 34). The battery 23 supplies direct current to the inverter 34. The battery 23 is disposed inside the revolving structure 12. More specifically, the battery 23 is disposed rearward of the electric pump device 22 inside the revolving structure 12. In this embodiment, the counterweight 16 is disposed at the rearmost position inside the revolving structure 12. The battery 23 is disposed between the counterweight 16 and the electric pump device 22. The battery 23 is also disposed inside the revolving structure 12 between the counterweight 16 and the electric pump device 22 with a space on both the left and right sides.

[0025] [Cooling System] The cooling system 1 is a system that cools multiple cooling targets in the excavator 2. The cooling system 1 includes multiple cooling system devices 41 to 44. In this embodiment, the cooling targets are the hydraulic fluid, the electric motor 32, the inverter 34, the battery 23, and the interior of the cabin 12a. The cooling system 1 includes four cooling system devices 41 to 44: a hydraulic fluid coolant 41, a motor radiator 42, a battery radiator 43, and an air condenser 44. Note that the cooling targets described above are merely examples, and do not necessarily include all of the hydraulic fluid, the inverter 34, the battery 23, and the interior of the cabin 12a. For example, the cooling targets cooled by the cooling system 1 described above may be at least two of the four targets described above. Furthermore, the cooling targets may be targets other than the four targets described above. Each component of the cooling system 1 will be described in more detail below.

[0026] The hydraulic fluid coolant 41 cools the hydraulic fluid returned to the tank 21. In this embodiment, the hydraulic fluid coolant 41 cools the actuators returned to the tank 21 from the hydraulic actuators via the multi-control valve 24. The hydraulic fluid coolant 41 includes a coolant core 41a and a coolant fan 41b. The coolant core 41a is a so-called heat exchanger and is disposed, for example, in the tank piping 21a connecting the multi-control valve 24 and the tank 21. The coolant core 41a cools the hydraulic fluid by passing the hydraulic fluid through it and exchanging heat between the hydraulic fluid and the air around the coolant core 41a. The coolant fan 41b further cools the hydraulic fluid by blowing air onto the coolant core 41a.

[0027] A coolant that cools the electric motor 32 flows through the electric motor radiator 42. More specifically, the coolant that cools the electric motor 32 and the inverter 34 flows through the electric motor radiator 42. As shown in FIG. 3 , the electric motor radiator 42 includes a radiator core 42a and a cooling fan 42b. The radiator core 42a is a heat exchanger and is connected to the inverter 34 via a pipe 42c. More specifically, a liquid path (not shown) is formed in the inverter 34. A liquid path (not shown) is also formed in the electric motor 32, and the liquid paths of the electric motor 32 and the inverter 34 are connected to each other. The radiator core 42a is connected to the liquid path of the inverter 34 via a pipe 42c. A circulation pump 42d is provided in the pipe 42c, and the circulation pump 42d circulates the coolant between the radiator core 42a and the liquid paths of the electric motor 32 and the inverter 34. The radiator core 42a cools the circulating coolant by passing it through and exchanging heat between the coolant and the air around the radiator core 42a. The cooled coolant flows through the liquid path, cooling the motor 32 and the inverter 34. The cooling fan 42b blows air onto the radiator core 42a, further cooling the coolant.

[0028] The battery radiator 43 shown in FIG. 2 cools the battery 23 with coolant. The battery radiator 43 includes a radiator core 43a and a cooling fan 43b. The radiator core 43a is a so-called heat exchanger and is connected to the battery 23 via piping 43c. More specifically, a liquid passage 23a is formed in the case of the battery 23. The radiator core 43a is connected to the liquid passage 23a of the battery 23 via piping 43c. A circulation pump 43d is also provided in the piping 43c. The circulation pump 43d circulates the coolant between the radiator core 43a and the liquid passage 23a. The radiator core 43a cools the coolant by passing the circulating coolant through it, thereby exchanging heat between the coolant and the air surrounding the radiator core 43a. The battery 23 is cooled by the cooled coolant flowing through the liquid passage 23a. The cooling fan 43b blows air onto the radiator core 43a to further cool the coolant.

[0029] The air condenser 44 is included in an air conditioner 45 that cools the interior of the cabin 12a and cools the refrigerant (e.g., cooling gas) circulating in the air conditioner 45. More specifically, the air conditioner 45, which is an example of air conditioning equipment, includes a compressor 45a, an air condenser 44, and an evaporator 45b. The compressor 45a pressurizes refrigerant gas to the air condenser 44. The air condenser 44 has a condenser core 44a and a condenser fan 44b. The refrigerant pressurized from the compressor 45a is guided to the condenser core 44a. The condenser core 44a passes the pressurized refrigerant gas through, thereby exchanging heat between the refrigerant gas and the air surrounding the condenser core 44a, thereby cooling the refrigerant. The condenser fan 44b further cools the refrigerant by blowing air onto the condenser core 44a. The refrigerant cooled by the condenser core 44a is sprayed onto the evaporator 45b by an evaporator (not shown). This vaporizes the refrigerant and cools the evaporator 45b. Cool air can be generated by passing air from a blower fan (not shown) through the cooled evaporator 45b. This allows the interior of the cabin 12a to be cooled. Furthermore, the refrigerant is heated by passing air from the blower fan through the evaporator 45b. The heated refrigerant is then sent to the compressor 45a. The refrigerant is then pressure-fed from the compressor 45a to the air condenser 44 again. Therefore, the refrigerant circulates within the air conditioner 45 while repeatedly absorbing and emitting heat, thereby cooling the evaporator 45b and thereby cooling the interior of the cabin 12a.

[0030] [Arrangement of Cooling System Devices] In the cooling system 1 configured as described above, the cooling system devices 41 to 44 are arranged in the excavator 2 (in the revolving bed 12 in this embodiment) as follows. That is, in the cooling system 1, the first cooling system devices 41, 42, that is, the hydraulic fluid coolant 41 and the electric motor radiator 42, are arranged on the right side of the battery 23. On the other hand, the second cooling system devices 43, 44, that is, the battery radiator 43 and the air capacitor 44, are arranged on the left side of the battery 23. In this way, the four cooling system devices 41 to 44 are arranged so as to sandwich the battery 23 in the left-right direction. Therefore, the left-right weight balance of the excavator 2 can be improved.

[0031] More specifically, the hydraulic fluid coolant 41 is disposed behind the tank 21, which is disposed on the right side within the revolving unit 12. This prevents the length of the tank piping 21a connecting the tank 21 and the hydraulic fluid coolant 41 from becoming too long. The motor radiator 42 is disposed behind the electric pump device 22, which is disposed on the right side. In this embodiment, the motor radiator 42 is disposed adjacent to the hydraulic fluid coolant 41 and is arranged side by side in the front-to-rear direction. The motor radiator 42 is disposed forward of the hydraulic fluid coolant 41. This prevents the length of the piping 42c connecting the motor radiator 42 and the inverter 34 from becoming too long.

[0032] Furthermore, the battery radiator 43 is disposed on the left side within the revolving unit 12. This prevents the length of the piping 43c connecting the radiator core 43a and the battery 23 from increasing. In this embodiment, the battery radiator 43 is disposed rearward of the cabin 12a. Furthermore, the air condenser 44 is disposed on the left side and rearward of the cabin 12a. In this embodiment, the air condenser 44 is adjacent to the battery radiator 43 and is disposed side by side in the front-to-rear direction. The air condenser 44 is disposed forward of the battery radiator 43. This prevents the length of the piping 45c connecting the air condenser 44 and the evaporator 45b from increasing.

[0033] In the cooling system 1 of this embodiment, the first cooling system devices 41, 42 and the second cooling system devices 43, 44 are disposed on both the left and right sides of the battery 23. This prevents the cooling system devices 41 to 44 from being disposed unevenly on one side of the battery 23 in the left-right direction. This improves the weight balance of the excavator 2 in the left-right direction.

[0034] Furthermore, in the cooling system 1 of this embodiment, the two first cooling system devices 41, 42 include a working fluid coolant 41 that cools the working fluid to be returned to the tank 21. Therefore, it is possible to prevent the portion of the tank piping 21a that connects the working fluid coolant 41 and the tank 21 from becoming long.

[0035] Furthermore, in the cooling system 1 of this embodiment, the two second cooling system devices 43, 44 include an air condenser 44 of an air conditioner 45 that cools the interior of the cabin 12a. Therefore, it is possible to prevent the length of the pipe 45c connecting the evaporator 45b of the air conditioner 45 and the air condenser 44 from increasing.

[0036] Furthermore, in the cooling system 1 of this embodiment, the two first cooling system devices 41, 42 include the motor radiator 42 through which the refrigerant flows to cool the inverter 34. Therefore, it is possible to prevent the length of the pipe 42c connecting the inverter 34 and the motor radiator 42 from becoming too long.

[0037] Furthermore, in the cooling system 1 of this embodiment, the two second cooling system devices 43, 44 include a battery radiator 43 through which a refrigerant flows to cool the battery 23. Therefore, it is possible to prevent the length of the pipe 43c connecting the battery 23 and the battery radiator 43 from becoming too long.

[0038] Furthermore, in the cooling system 1 of this embodiment, the two first cooling system devices 41, 42 include a hydraulic fluid coolant 41 and an electric motor radiator 42. The two second cooling system devices 43, 44 include an air condenser 44 of an air conditioner 45 and a battery radiator 43. Therefore, the hydraulic fluid coolant 41, the electric motor radiator 42, the air condenser 44, and the battery radiator 43 provided in the excavator 2 can be arranged in a balanced manner on both the left and right sides of the battery 23. Furthermore, the hydraulic fluid coolant 41, the electric motor radiator 42, the air condenser 44, and the battery radiator 43 can be arranged near the objects to be cooled. Therefore, the length of each of the pipes 21a, 42c, 43c, and 45c can be reduced.

[0039] In the excavator 2 of this embodiment, the electric pump device 22 is disposed on the right side within the revolving body 12. The cabin 12a is disposed on the opposite side of the boom 13 from the electric pump device 22, i.e., on the left side. The battery 23 is disposed rearward of the electric pump device 22 and the cabin 12a. The hydraulic fluid coolant 41, the electric motor radiator 42, the air capacitor 44, and the battery radiator 43 are disposed on both left and right sides of the battery 23, respectively. This enables the weight balance of the excavator 2 to be improved.

[0040] <Other Embodiments> In this embodiment, the excavator 2 is used as an example of an electric construction machine equipped with the cooling system 1. However, the electric construction machine may also be a crane, a bulldozer, or a wheel loader. The cooling target may also be something other than those described above. Furthermore, in the cooling system 1, the coolant for cooling the inverter 34 flows from the motor radiator 42 to the inverter 34 as well as the motor 32. In the cooling system, a separate inverter radiator may be provided to supply coolant to the inverter 34, separate from the motor 32. In this case, the cooling system 1 includes a pump radiator and a motor radiator as first cooling system devices and pump device radiators. Furthermore, the first cooling system devices 41, 42 do not necessarily need to be arranged in the front-to-rear direction, but may also be arranged in the up-down direction or in a staggered arrangement. The same applies to the second cooling system devices 43, 44. Furthermore, there may be only one first cooling system device and one second cooling system device. Furthermore, the battery radiator 43 does not necessarily have to be located on the left side, but may be located on the right side. Furthermore, the first cooling system devices and the second cooling system devices do not necessarily have to be the same number, but one of them may be more. In addition, in this embodiment, the electric pump device 22 is a vertically mounted electric pump device in which the hydraulic pump 31 and the electric motor 32 are aligned vertically, but it may also be a horizontally mounted electric pump device in which the hydraulic pump 31 and the electric motor 32 are aligned horizontally or longitudinally, etc.

[0041] <Illustrative embodiment> A cooling system for an electric construction machine in a first aspect is a cooling system for an electric construction machine equipped with an electric pump device driven by power supplied from a battery, and is equipped with a plurality of cooling system devices that cool a plurality of cooling objects including the battery and the electric pump device, respectively, and the plurality of cooling system devices include at least one first cooling system device and at least one second cooling system device, and the first cooling system device and the second cooling system device are respectively arranged on one side of the battery in a first direction and on the other side of the first direction.

[0042] According to the above aspect, the first cooling system device and the second cooling system device are respectively disposed on one side in the first direction and the other side in the first direction with the battery in between. This makes it possible to prevent the cooling system devices from being disposed biased to one side of the battery in the first direction. This makes it possible to improve the weight balance in the first direction of the electric construction machine.

[0043] In a second aspect, the cooling system for an electric construction machine is the cooling system for an electric construction machine of the first aspect, wherein a tank for storing working fluid discharged from the electric pump device is arranged on one side in a first direction in the electric construction machine, and the at least one first cooling system device includes a working fluid coolant for cooling the working fluid to be returned to the tank.

[0044] According to the above aspect, the at least one first cooling system device includes a working fluid coolant that cools the working fluid to be returned to the tank, thereby preventing the length of the piping connecting the working fluid coolant and the tank from becoming too long.

[0045] In a third aspect, the cooling system for an electric construction machine is the cooling system for an electric construction machine of the first or second aspect, wherein the electric pump device is arranged on one side in a first direction and a cabin is arranged on the other side in the first direction, and the at least one second cooling system device includes a condenser of an air conditioning system that cools the inside of the cabin.

[0046] According to the above aspect, the at least one second cooling system device includes a condenser of an air conditioning system that cools the cabin, thereby preventing a pipe connecting the evaporator and the condenser of the air conditioning system from becoming long.

[0047] A cooling system for an electric construction machine in a fourth aspect is the cooling system for an electric construction machine of any one of the first to third aspects, wherein the electric pump device is arranged on one side in a first direction in the electric construction machine, the electric pump device includes a hydraulic pump that discharges working fluid, and an electric motor that drives the hydraulic pump, and the at least one first cooling system device includes an electric motor radiator through which a refrigerant that cools the electric motor flows.

[0048] According to the above aspect, the at least one first cooling system device includes a motor radiator, which makes it possible to prevent the length of the piping connecting the electric motor and the motor radiator from increasing.

[0049] In a fifth aspect, the cooling system for an electric construction machine is the cooling system for an electric construction machine of the fourth aspect, wherein the electric pump device further includes an inverter connected to the battery and the electric motor, and a refrigerant that cools the electric motor and the inverter flows through the electric motor radiator.

[0050] According to the above aspect, the radiator for the electric motor allows the coolant for cooling the electric motor and the inverter to flow, thereby cooling the inverter as well as the electric motor.

[0051] In a sixth aspect, the cooling system for an electric construction machine is the cooling system for an electric construction machine of any one of the first to fifth aspects, wherein the at least one second cooling system device includes a battery radiator through which a refrigerant that cools the battery flows.

[0052] According to the above aspect, the at least one second cooling system device includes a battery radiator through which a refrigerant for cooling the battery flows, thereby preventing the length of the piping connecting the battery and the battery radiator from increasing.

[0053] A cooling system for an electric construction machine in a seventh aspect is the cooling system for an electric construction machine of the second aspect, wherein the electric pump device is arranged on one side in a first direction and a cabin is arranged on the other side in the first direction of the electric construction machine, the at least one first cooling system device includes a pump device radiator through which a refrigerant that cools the electric pump device flows, and the at least one second cooling system device includes a condenser of an air conditioning system that cools the inside of the cabin, and a battery radiator through which a refrigerant that cools the battery flows.

[0054] According to the above aspect, the at least one first cooling system device includes a pump device radiator. The at least one second cooling system device includes a condenser for the air conditioning system and a battery radiator. Therefore, the hydraulic fluid coolant, the pump device radiator, the condenser, and the battery radiator provided in the electric construction machine can be arranged in a balanced manner on both sides of the battery in the first direction. Furthermore, because the hydraulic fluid coolant, the pump device radiator, the condenser, and the battery radiator can each be arranged near the object to be cooled, the length of each piping can be reduced.

[0055] In an eighth aspect, the shovel comprises the cooling system of the electric construction machine of any one of the first to seventh aspects, a traveling device, a rotating body rotatably mounted on the traveling device, a boom swingably mounted on the rotating body, the battery, and the electric pump device driven by power supplied from the battery, wherein the rotating body has the cabin, the electric pump device is arranged on one side in a first direction within the rotating body, the cabin is arranged on the opposite side of the electric pump device across the boom, and the battery is arranged on one side in a second direction perpendicular to the first direction with respect to the electric pump device and the cabin.

[0056] According to the above aspect, the electric pump unit is disposed on one side in a first direction within the revolving body. The cabin is disposed on the opposite side of the boom from the electric pump unit. The battery is disposed on one side in a second direction perpendicular to the first direction relative to the electric pump unit and the cabin. The hydraulic fluid coolant, the capacitor, the inverter radiator, and the battery radiator are disposed on both sides of the battery in the first direction. This improves the weight balance of the electric construction machine.

[0057] From the above description, many modifications and other embodiments of the present disclosure will be apparent to those skilled in the art. Therefore, the above description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode for carrying out the present disclosure. Details of the structure and / or function thereof can be substantially changed without departing from the spirit of the present disclosure.

Claims

1. A cooling system for an electric construction machine equipped with an electric pump device driven by power supplied from a battery, comprising a plurality of cooling system devices that cool a plurality of cooling objects including the battery and the electric pump device, the plurality of cooling system devices including at least one first cooling system device and at least one second cooling system device, the first cooling system device and the second cooling system device being respectively arranged on one side in a first direction and the other side in the first direction with the battery in between.

2. A cooling system for an electric construction machine as described in claim 1, wherein a tank for storing the working fluid discharged from the electric pump device is disposed on one side in a first direction in the electric construction machine, and the at least one first cooling system device includes a working fluid coolant for cooling the working fluid returned to the tank.

3. A cooling system for an electric construction machine as described in claim 1, wherein the electric pump device is disposed on one side in a first direction of the electric construction machine and a cabin is disposed on the other side in the first direction, and the at least one second cooling system device includes a condenser of an air conditioning facility that cools the inside of the cabin.

4. A cooling system for an electric construction machine as described in claim 1, wherein the electric pump device is arranged on one side in a first direction in the electric construction machine, the electric pump device includes a hydraulic pump that discharges hydraulic fluid, and an electric motor that drives the hydraulic pump, and the at least one first cooling system device includes a motor radiator through which a refrigerant that cools the electric motor flows.

5. A cooling system for an electric construction machine as described in claim 4, wherein the electric pump device further includes an inverter connected to the battery and the electric motor, and a refrigerant for cooling the electric motor and the inverter flows through the electric motor radiator.

6. A cooling system for an electric construction machine according to claim 1, wherein the at least one second cooling system device includes a battery radiator through which a coolant for cooling the battery flows.

7. A cooling system for an electric construction machine as described in claim 2, wherein the electric pump device is disposed on one side in a first direction and a cabin is disposed on the other side in the first direction, the at least one first cooling system device includes a pump device radiator through which a refrigerant for cooling the electric pump device flows, and the at least one second cooling system device includes a condenser of an air conditioning equipment that cools the cabin, and a battery radiator through which a refrigerant for cooling the battery flows.

8. An electric construction machine comprising: the cooling system of the electric construction machine described in claim 7; a traveling gear; a rotating body rotatably mounted on the traveling gear; a boom swingably mounted on the rotating body; the battery; and the electric pump unit driven by power supplied from the battery, wherein the rotating body has the cabin, the electric pump unit is arranged on one side in a first direction within the rotating body, the cabin is arranged on the opposite side of the electric pump unit across the boom, and the battery is arranged on one side in a second direction perpendicular to the first direction with respect to the electric pump unit and the cabin.

Images