Electric shovel

Abstract

To provide an electric shovel which can shorten a length of a hydraulic pipe.SOLUTION: A rotating frame 20 rotates around a center CP of rotation. A battery 31 is supported on the rotating frame 20. An electric motor 33 is supported on the rotating frame 20, and power is supplied to the electric motor from the battery 31. A hydraulic pump 34 is supported on the turning frame 20, is driven by the electric motor 33, and is arranged near the center CP of rotation rather than the electric motor 33 in plan view.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] Conventionally, battery-powered electric shovels are disclosed, for example, in JP 11-140906 A (Patent Document 1) and JP 2012-1933 A (Patent Document 2). Patent Documents 1 and 2 disclose a small electric shovel in which a battery, an electric motor, and a hydraulic pump are arranged in this order from the rear to the front of a rotating body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-140906 [Patent Document 2] JP 2012-1933 A Summary of the Invention [Problem to be solved by the invention]

[0004] The battery is disposed at the rear of the rotating body so as to also function as a counterweight. However, in the case of a large battery-powered electric shovel (hereinafter referred to as an "electric shovel"), the space occupied by the battery becomes large. As a result, the battery protrudes from the arrangement area as a counterweight into the machine room, making it difficult to arrange necessary components such as an electric motor and a hydraulic pump in the machine room. Therefore, if the arrangement of the battery, electric motor, and hydraulic pump as described in Patent Documents 1 and 2 is applied to a large electric shovel, the hydraulic piping becomes long, causing pressure loss in the hydraulic pressure and deteriorating energy efficiency.

[0005] An object of the present disclosure is to provide an electric shovel that can shorten the length of hydraulic piping. [Means for solving the problem]

[0006] The electric excavator of the present disclosure includes a hydraulic actuator, a revolving frame, a battery, an electric motor, and a hydraulic pump. The revolving frame revolves around a revolving center. The battery is supported by the revolving frame. The electric motor is supported by the revolving frame and is driven by the battery as a power source. The hydraulic pump is supported by the revolving frame, driven by the electric motor to supply oil to the hydraulic actuator, and disposed closer to the revolving center than the electric motor in a plan view. Effect of the Invention

[0007] According to the present disclosure, it is possible to realize an electric shovel that can shorten the length of hydraulic piping. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a schematic configuration of an electric shovel according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a perspective view showing the configuration of a revolving frame and its mounted items in the electric excavator shown in FIG. [Diagram 3] 2 is a plan view showing the configuration of a revolving frame and its mounted items in the electric excavator shown in FIG. 1. [Figure 4] FIG. 2 is a side view showing a state in which a hydraulic pump is disposed below the hydraulic oil tank. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the specification and drawings, the same or corresponding components are denoted by the same reference numerals, and redundant explanations are not repeated. In addition, in the drawings, configurations may be omitted or simplified for convenience of explanation. In addition, at least some of the embodiments and modifications may be combined with each other in any desired manner.

[0010] In the following description, the terms "up," "down," "front," "rear," "left," and "right" refer to directions based on an operator seated in the operator's seat 4S in the operator's cab 4 shown in FIG.

[0011] <Electric excavator configuration> First, the configuration of the electric shovel of this embodiment will be described with reference to FIG.

[0012] FIG. 1 is a perspective view showing a schematic configuration of an electric shovel in one embodiment of the present disclosure. As shown in FIG. 1, the electric shovel 100 has a main body 1 and a working machine 2 operated by hydraulic pressure. The main body 1 has a revolving body 3 and a traveling body 5. The traveling body 5 has a pair of tracks 5Cr and a traveling motor 5M. The electric shovel 100 can travel by rotation of the tracks 5Cr. The traveling motor 5M is provided as a drive source for the traveling body 5. The traveling motor 5M is a hydraulic motor operated by hydraulic pressure. The traveling body 5 may have wheels (tires). The traveling motor 5M or the revolving motor 37 may be an electric motor.

[0013] The rotating body 3 is disposed on the running body 5 and is supported by the running body 5. The rotating body 3 can be rotated relative to the running body 5 about a rotation axis RX by a rotation motor 37 (FIG. 3). The rotation motor 37 is a hydraulic motor that is hydraulically operated. The rotation axis RX is an imaginary straight line that serves as the rotation center of the rotating body 3.

[0014] The rotating body 3 has a driver's cab 4. A driver's seat 4S where an operator sits is provided in the driver's cab 4. The operator (crew) gets into the driver's cab 4 and can operate the work equipment 2, rotate the rotating body 3 relative to the running body 5, and travel the electric excavator 100 using the running body 5.

[0015] The rotating body 3 has an exterior cover 9. The exterior cover 9 covers a machine room in which a battery, an inverter, an electric motor, a hydraulic pump, a rotating motor, a switching valve, a hydraulic oil tank, and the like are disposed.

[0016] The work machine 2 is supported by a rotating body 3. The work machine 2 has a boom 6, an arm 7, and a bucket 8. The work machine 2 further has a boom cylinder 10, an arm cylinder 11, and a bucket cylinder 12.

[0017] The boom 6 is rotatably connected to the main body 1 (the traveling body 5 and the rotating body 3). Specifically, a base end of the boom 6 is rotatably connected to the rotating body 3 with a boom foot pin 13 as a fulcrum.

[0018] The arm 7 is rotatably connected to the boom 6. Specifically, a base end of the arm 7 is rotatably connected to the tip of the boom 6 with a boom top pin 14 as a fulcrum. The bucket 8 is rotatably connected to the arm 7. Specifically, a base end of the bucket 8 is rotatably connected to the tip of the arm 7 with an arm top pin 15 as a fulcrum.

[0019] One end of the boom cylinder 10 is connected to the rotating body 3, and the other end is connected to the boom 6. The boom 6 can be driven relative to the main body 1 by the boom cylinder 10. By this drive, the boom 6 can be rotated in the vertical direction relative to the rotating body 3 with the boom foot pin 13 as a fulcrum.

[0020] One end of the arm cylinder 11 is connected to the boom 6, and the other end is connected to the arm 7. The arm 7 can be driven relative to the boom 6 by the arm cylinder 11. By this drive, the arm 7 can rotate up and down or back and forth relative to the boom 6 with the boom top pin 14 as a fulcrum.

[0021] One end of the bucket cylinder 12 is connected to the arm 7, and the other end is connected to a bucket link 17. The bucket 8 can be driven relative to the arm 7 by the bucket cylinder 12. By this drive, the bucket 8 can rotate in the vertical direction relative to the arm 7 with the arm top pin 15 as a fulcrum.

[0022] Each of the boom cylinder 10, the arm cylinder 11 and the bucket cylinder 12 is a hydraulic cylinder and is driven by hydraulic pressure.

[0023] <Configuration of rotating frame and placement of mounted items> Next, the configuration of the revolving frame and the arrangement of the mounting parts of the revolving frame in the electric excavator shown in FIG. 1 will be described with reference to FIGS. 2 and 3. FIG.

[0024] Fig. 2 and Fig. 3 are a perspective view and a plan view, respectively, showing the configuration of a revolving frame and the arrangement of objects mounted thereon in the electric excavator shown in Fig. 1. As shown in Fig. 2, the revolving body 3 (Fig. 1) has a revolving frame 20. The revolving frame 20 revolves around a revolving axis RX relative to the traveling body 5 (Fig. 1).

[0025] The rotating frame 20 has a center frame CF, a left deck DL, and a right deck DR. The center frame CF is located approximately in the center in the left-right direction of the rotating frame 20. The left deck DL is disposed on the left side of the center frame CF. The right deck DR is disposed on the right side of the center frame CF.

[0026] The center frame CF has a pair of center beams CB. The pair of center beams CB are arranged to face each other with a gap in the left-right direction. The pair of center beams CB support a work machine 2 (FIG. 1). In this way, the center frame CF supports the work machine 2.

[0027] Each of the pair of center beams CB has through holes TH1 and TH2. A boom foot pin 13 (FIG. 1) is inserted through the through hole TH1. A boom 6 (FIG. 1) is rotatably supported by the pair of center beams CB by the boom foot pin 13.

[0028] A pin (not shown) that supports the boom cylinder 10 (FIG. 1) is inserted through the through hole TH2. The boom cylinder 10 is rotatably supported by the center beam CB by this pin.

[0029] The front end FL of the left deck DL and the front end FR of the right deck DR are each located forward of the front end FF of the center frame CF. The rear end RC of each of the pair of center beams CB are located rearward of the rear ends RL of the left deck DL and RR of the right deck DR. The rear end RC of each of the pair of center beams CB forms the rearmost end of the center frame CF.

[0030] A bracket 22 is connected to the upper rear surfaces of the pair of center beams CB by, for example, welding. A rear end 22R of the bracket 22 is located forward of the rear ends RC of the pair of center beams CB and rearward of the rear ends RL of the left deck DL and RR of the right deck DR. A front end 22F of the bracket 22 is located forward of the rear ends RL of the left deck DL and RR of the right deck DR.

[0031] 3, the rotating frame 20 supports loads such as a battery 31, an inverter 32, an electric motor 33, a hydraulic pump 34, a switching valve 35, a hydraulic oil tank 36, and a rotating motor 37. The output shaft of the electric motor 33 is mechanically connected to the input shaft of the hydraulic pump 34.

[0032] The battery 31 includes, for example, a plurality of battery modules, each of which has a battery cell. The battery 31 is a power source and stores electrical energy obtained from an external power source. The battery 31 extracts the stored electrical energy as electromotive force. The battery 31 supplies power to the inverter 32 through electrical wiring.

[0033] The inverter 32 converts the DC power output from the battery 31 into AC power with frequency and other factors controlled. The inverter 32 supplies the AC power to the electric motor 33 through electrical wiring. In this way, the inverter 32 controls the driving of the electric motor 33. The electrical energy stored in the battery 31 in this manner is supplied to the electric motor 33.

[0034] The electric motor 33 is driven by AC power supplied from the inverter 32, using the battery 31 as a power source. The rotation speed of the electric motor 33 is controlled by the frequency of the AC power supplied from the inverter 32. When the electric motor 33 is driven, a hydraulic pump 34 to which the driving force of the electric motor 33 is transmitted is driven.

[0035] When the hydraulic pump 34 is driven, it supplies hydraulic oil to each of the hydraulic actuators 5M, 37, 10-12 through a switching valve 35 (main valve). Specifically, when the hydraulic pump 34 is driven, it pumps out hydraulic oil from a hydraulic oil tank 36 through hydraulic piping. The hydraulic oil tank 36 serves to supply oil to the hydraulic pump 34. The hydraulic oil discharged from the hydraulic pump 34 is supplied to the switching valve 35 through the hydraulic piping.

[0036] The switching valve 35 is configured as an assembly of a large number of control valves, pilot valves, etc. The switching valve 35 is disposed in an oil passage (hydraulic piping) between the hydraulic pump 34 and the hydraulic actuators. The switching valve 35 supplies and discharges hydraulic oil pumped from a hydraulic oil tank 36 by the hydraulic pump 34 to and from the hydraulic actuators. The hydraulic actuators have, for example, hydraulic cylinders (boom cylinder 10, arm cylinder 11, bucket cylinder 12), a swing motor 37, and a travel motor 5M. The hydraulic actuators 5M, 37, 10-12 are operated by the supply and discharge of hydraulic oil from the switching valve 35.

[0037] The opening and closing of each valve in the switching valve 35 is controlled in response to driving operations by the operator. This allows the main body 1 and the work equipment 2 of the electric excavator 100 to be operated in response to driving operations by the operator in the driver's cab 4. Specifically, the operator can operate the work equipment 2 by operating the hydraulic cylinders 10-12, can operate the rotation of the rotating body 3 by operating the swing motor 37, and can operate the traveling of the electric excavator 100 by operating the traveling motor 5M.

[0038] The battery 31 is supported by the revolving frame 20 by being disposed on the bracket 22. The left-right dimension W1 of the battery 31 is larger than the left-right dimension W2 of the center frame CF. The left-right dimension W1 of the battery 31 is the dimension from the right end RE to the left end LE of the battery 31. The left-right dimension W2 of the center frame CF is the dimension from the right end to the left end of the center frame CF.

[0039] Therefore, in a plan view, the right end RE of the battery 31 is located directly above the right deck DR, and the left end LE of the battery 31 is located directly above the left deck DL. In this specification, a plan view refers to a viewpoint looking down from above in a direction perpendicular to the bottom plate BP of the rotating frame 20 (the up-down direction).

[0040] The electric shovel 100 of this embodiment does not have a counterweight, and the battery 31 serves as the counterweight. For this reason, the battery 31 is disposed at the rear of the rotating body 3.

[0041] The area behind the rear end RL of the left deck DL and the rear end RR of the right deck DR is originally an area where a counterweight is placed. The battery 31 has a portion located behind the rear end RL of the left deck DL and the rear end RR of the right deck DR in a plan view to serve as a counterweight. Therefore, the rear end 31R of the battery 31 is located behind the rear end RL of the left deck DL and the rear end RR of the right deck DR in a plan view.

[0042] However, in a large electric excavator, the battery 31 also becomes large. If the height of the battery is increased, the rear visibility of the operator seated in the driver's seat 4S becomes poor. For this reason, the battery 31 cannot be contained within the arrangement area of ​​the counterweight and protrudes into the machinery room. As a result, in a plan view, the front end 31F of the battery 31 is located forward of both the rear end RL of the left deck DL and the rear end RR of the right deck DR. As a result of the battery 31 protruding into the machinery room in this way, restrictions are imposed on the arrangement of items mounted other than the battery 31.

[0043] The machine room refers to a space located forward of each of the rear ends RL and RR of the left deck DL and the right deck DR, and is covered by an exterior cover 9.

[0044] In this embodiment, the inverter 32, the electric motor 33, the hydraulic pump 34, and the hydraulic oil tank 36 are each supported on the right deck DR. The inverter 32, the electric motor 33, the hydraulic pump 34, and the hydraulic oil tank 36 are each disposed on the front side of the battery 31 (on the front end FR side of the right deck DR).

[0045] The hydraulic oil tank 36, the hydraulic pump 34, the electric motor 33, and the inverter 32 are arranged in this order from the rear end RR side to the front end FR side of the right deck DR. That is, the hydraulic oil tank 36 is arranged in front of the battery 31, the hydraulic pump 34 is arranged in front of the hydraulic oil tank 36, the electric motor 33 is arranged in front of the hydraulic pump 34, and the inverter 32 is arranged in front of the electric motor 33.

[0046] In a plan view, a gap is provided between the front end 31F of the battery 31 and the rear end of the hydraulic oil tank 36, between the front end of the hydraulic oil tank 36 and the rear end of the hydraulic pump 34, and between the front end of the electric motor 33 and the rear end of the inverter 32.

[0047] The rear end of the hydraulic pump 34 is located rearward of the position of the through hole TH1 in the front-rear direction (toward the rear end RR of the right deck DR). The rear end of the electric motor 33 is located forward of the position of the through hole TH1 in the front-rear direction (toward the front end FR of the right deck DR). The rear end of the inverter 32 is located forward of the position of the front end FF of the center frame CF in the front-rear direction (toward the front end FR of the right deck DR).

[0048] In a plan view, the hydraulic oil tank 36 is disposed between the hydraulic pump 34 and the battery 31. In a plan view, the hydraulic pump 34 is disposed closer to the battery 31 than the electric motor 33 is.

[0049] The center frame CF supports each of the switching valve 35 and the swing motor 37. Each of the switching valve 35 and the swing motor 37 is disposed in an area sandwiched between a pair of center beams CB in a plan view.

[0050] The switching valve 35 and the swing motor 37 are each disposed on the front side of the battery 31 (on the front end FF side of the center frame CF).

[0051] The switching valve 35 and the swing motor 37 are disposed in this order from the rear end RC side to the front end FF side of the center frame CF. That is, the switching valve 35 is disposed in front of the battery 31, and the swing motor 37 is disposed in front of the switching valve 35. The switching valve 35 is disposed between the battery 31 and the swing motor 37, and is disposed closer to the battery 31 than the swing motor 37.

[0052] An opening 21 is disposed in front of the revolving motor 37. The opening 21 is a through hole provided in the bottom plate BP of the revolving frame 20. For example, a swivel joint (not shown) is inserted into the opening 21. The opening 21 has a substantially circular shape in a plan view. Note that a protrusion protruding from the circular periphery of the opening 21 toward the inner periphery may be provided to fix the body of the swivel joint. The revolving axis RX passes through the center of the substantially circular shape of the opening 21 in a plan view. Therefore, the center CP of the substantially circular shape of the opening 21 in a plan view becomes the revolving center (rotation center) of the revolving body 3 with respect to the traveling body 5. In other words, the revolving frame 20 revolves around the revolving center CP.

[0053] In a plan view, the hydraulic pump 34 is disposed closer to the rotation center CP (rotation axis RX) than the electric motor 33. Specifically, in a plan view, the shortest distance L1 between the rotation center CP and the hydraulic pump 34 is shorter than the shortest distance L2 between the rotation center CP and the electric motor 33.

[0054] The hydraulic pump 34 is disposed closer to the switching valve 35 than the electric motor 33. Specifically, in a plan view, the shortest distance L3 between the switching valve 35 and the hydraulic pump 34 is shorter than the shortest distance L4 between the switching valve 35 and the electric motor 33.

[0055] A driver's cab 4 (FIG. 1) is supported at the front of the left deck DL. The inverter 32, the electric motor 33, the hydraulic pump 34, and the hydraulic oil tank 36 may each be supported on the left deck DL, and the driver's cab 4 may be disposed on the right deck DR.

[0056] Further, in the above embodiment, the hydraulic pump and the hydraulic oil tank are arranged side by side in the front-to-rear direction. However, the hydraulic pump and the hydraulic oil tank may be arranged side by side above and below each other.

[0057] Fig. 4 is a side view (A) and a plan view (B) showing a state in which a hydraulic pump is disposed below a hydraulic oil tank. As shown in Figs. 4(A) and (B), the hydraulic oil tank 36 is disposed directly above the hydraulic pump 34. Therefore, in the plan view shown in Fig. 4(B), the entire hydraulic pump 34 overlaps with the hydraulic oil tank 36. Also, unlike the arrangement in Fig. 3, when the hydraulic oil tank 36 is disposed in front of the right deck DR, it may be located directly above the electric motor 33. In this case, a part or the entire electric motor 33 overlaps with the hydraulic oil tank 36.

[0058] 4(A), in this arrangement, the underside LS2 of the hydraulic oil tank 36 is located above the hydraulic pump 34. For this reason, the oil piping OL connecting the hydraulic oil tank 36 and the hydraulic pump 34 is connected to the underside LS2 of the hydraulic oil tank 36 at a position higher than the hydraulic pump 34. The oil piping OL extends downward from the connection portion with the hydraulic oil tank 36 behind the hydraulic pump 34, passes between the underside LS1 of the hydraulic pump 34 and the bottom plate BP of the revolving frame 20, and is then connected to the underside LS1 of the hydraulic pump 34.

[0059] <Effects> Next, the effects of this embodiment will be described.

[0060] As shown in Fig. 3, the hydraulic oil is supplied from the switching valve 35 to the traveling motor 5M (Fig. 1) through a swivel joint inserted into the opening 21 of the revolving frame 20. The revolving motor 37 is disposed near the revolving center CP so that the rotary shaft of the revolving motor 37 meshes with the revolving gear. The work machine 2 is supported by the revolving frame 20 near the revolving center CP.

[0061] Therefore, by arranging the switching valve 35 near the swing center CP, it is possible to shorten the length of the hydraulic piping from the switching valve 35 to the traveling motor 5M, the swing motor 37, and the hydraulic cylinders 10 to 12. Therefore, by arranging the hydraulic pump 34 near the swing center CP, it is possible to shorten the length of the hydraulic piping from the hydraulic pump 34 to the switching valve 35.

[0062] 3, in the present embodiment, the hydraulic pump 34 is disposed closer to the rotation center CP in plan view than the electric motor 33. Therefore, as described above, the length of the hydraulic piping from the hydraulic pump 34 through the switching valve 35 to each of the hydraulic actuators 5M, 37, 10 to 12 can be shortened. This makes it possible to suppress pressure loss occurring in the hydraulic pressure, and achieves good energy efficiency.

[0063] 3, according to this embodiment, the hydraulic pump 34 is disposed closer to the switching valve 35 than the electric motor 33. This makes it possible to shorten the length of the hydraulic piping from the hydraulic pump 34 to the switching valve 35. This makes it possible to further reduce pressure loss occurring in the hydraulic pressure from the hydraulic pump 34 to the switching valve 35, thereby achieving even better energy efficiency.

[0064] 3, according to this embodiment, the electric motor 33 and the hydraulic pump 34 are supported on either the right deck DR or the left deck DL. This allows the electric motor 33 and the hydraulic pump 34 to be disposed on the revolving frame 20 even if the battery 31 is enlarged.

[0065] 3, the battery 31 has a portion located rearward of the rear end RR of the right deck DR and the rear end RL of the left deck DL in the front-rear direction, which allows the battery 31 to function as a counterweight.

[0066] 3, in this embodiment, the switching valve 35 is disposed in an area sandwiched between a pair of center beams CB in a plan view. This makes it possible to shorten the length of the hydraulic piping extending from the switching valve 35 to each of the hydraulic actuators 5M, 37, 10-12.

[0067] 3, the hydraulic oil tank 36 is disposed between the hydraulic pump 34 and the battery 31 in a plan view. This allows the length of the oil piping connecting the hydraulic pump 34 and the hydraulic oil tank 36 to be shortened.

[0068] 4, the hydraulic pump 34 is disposed below the hydraulic oil tank 36. This improves the oil suction performance of the hydraulic pump 34. Furthermore, by arranging the hydraulic pump 34 and the hydraulic oil tank 36 one above the other, the hydraulic pump 34 and the hydraulic oil tank 36 can be arranged compactly in the front-rear direction.

[0069] 3, according to this embodiment, the inverter 32 is disposed in front of the electric motor 33. This allows the length of the electrical wiring connecting the inverter 32 and the electric motor 33 to be shortened.

[0070] In addition, when the electric shovel 100 is remotely operated and there is no need for an operator to board the electric shovel 100, the operator's cab 4 may be omitted.

[0071] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0072] 1 main body, 2 work machine, 3 rotating body, 4 driver's cab, 4S driver's seat, 5 running body, 5Cr track, 5M running motor, 6 boom, 7 arm, 8 bucket, 9 exterior cover, 10 boom cylinder, 11 arm cylinder, 12 bucket cylinder, 13 boom foot pin, 14 boom top pin, 15 arm top pin, 17 bucket link, 20 rotating frame, 21 opening, 22 bracket, 22F, 31F, FF, FL, FR front end, 22R, 31R, RC, RL, RR rear end, 31 battery, 32 inverter, 33 electric motor, 34 hydraulic pump, 35 switching valve, 36 hydraulic oil tank, 37 rotating motor, 100 electric shovel, BP bottom plate, CB center beam, CF center frame, CP rotating center, DL left deck, DR right deck, LE left end, LS1, LS2 Bottom surface, OL oil piping, RE right end, RX rotation axis (rotation center), TH1, TH2 through holes.

Claims

1. A work machine, A hydraulic actuator that drives the working machine; A rotating frame is disposed on the upper portion of the traveling body and rotates around a rotation center by a rotation motor; A battery supported by the rotating frame; an electric motor supported by the rotating frame and driven by the battery; a hydraulic pump driven by the electric motor to supply oil to the hydraulic actuator; A switching valve is disposed in an oil passage between the hydraulic pump and the hydraulic actuator, The rotating frame includes a center frame that supports the working machine, and a pair of decks disposed on the left and right of the center frame, the battery is disposed to have a portion located rearward of the rear end positions of the pair of decks, the electric motor and the hydraulic pump are supported on one of the pair of decks; The center frame has a pair of center beams that support the work machine, An electric excavator, wherein, in a plan view, the switching valve and the swing motor are disposed in an area sandwiched between the pair of center beams, and the hydraulic pump is adjacent to the switching valve and the swing motor across the center beam.

2. An electric excavator as described in claim 1, wherein the hydraulic pump is positioned closer to the switching valve than the electric motor.

3. The electric energy stored in the battery is supplied to the electric motor, The electric motor is driven by the supply of the electric energy, 3. The electric shovel according to claim 1, wherein the oil from the hydraulic pump is supplied to the hydraulic actuator via the switching valve by driving the electric motor.

4. A hydraulic oil tank is further provided to supply oil to the hydraulic pump. The electric shovel according to claim 1 , wherein the hydraulic oil tank is disposed between the hydraulic pump and the battery in a plan view.

5. A hydraulic oil tank is further provided to supply oil to the hydraulic pump. The electric shovel according to claim 1 , wherein the hydraulic pump is disposed below the hydraulic oil tank.

6. The electric motor is further provided with an inverter for controlling the driving of the electric motor. The electric shovel according to claim 1 , wherein the inverter is disposed in front of the electric motor.

7. An electric excavator as described in any one of claims 1 to 3, wherein the hydraulic actuator is a hydraulic cylinder that drives the working machine.

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