Electric work machine

Abstract

To provide an electric work machine that can increase battery capacity by providing as large a battery unit as possible in a limited space inside a machine body, while efficiently cooling devices inside a machine body.SOLUTION: A hydraulic shovel as an electric work machine comprises, within the machine body: a battery unit storing electricity; an electric motor driven by electricity supplied from the battery unit; a hydraulic pump driven by the electric motor; an oil cooler cooling hydraulic oil discharged from the hydraulic pump; and a fan drawing air into the machine body. The machine body has a first opening and a second opening, the first opening is provided at one lateral side of the machine body, and the second opening is provided at the other lateral side of the machine body. The fan is disposed so as to face the first opening in the machine body, and the oil cooler is disposed so as to face the second opening in the machine body.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an electric work machine. [Background technology]

[0002] 2. Description of the Related Art Electric construction machinery equipped with a battery unit inside the machine body is known as a conventional technique (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-97079 Summary of the Invention [Problem to be solved by the invention]

[0004] In a small electric work machine, it is desirable to provide a large battery unit in the limited space inside the machine to increase the battery capacity and extend the operating time. At the same time, it is also desirable to efficiently cool the equipment inside the machine (including the battery unit). Patent Document 1 takes into consideration the issue of ensuring a large space for arranging the battery unit, but does not take into consideration the issue of efficiently cooling the equipment inside the machine. In this respect, the electric construction machine of Patent Document 1 has room for improvement.

[0005] The present invention has been made to solve the above problems, and its object is to provide an electric work machine that can efficiently cool equipment inside the machine while allowing as large a battery unit as possible to be installed in the limited space inside the machine, thereby increasing battery capacity. [Means for solving the problem]

[0006] An electric working machine according to one aspect of the present invention includes, within a body of the machine, a battery unit that stores electric power, an electric motor that is driven by receiving a supply of electric power from the battery unit, a hydraulic pump driven by the electric motor, an oil cooler that cools hydraulic oil discharged from the hydraulic pump, and a fan that takes in air into the body of the machine, the body having a first opening and a second opening, the first opening being provided on one side of the body and the second opening being provided on the other side of the body, the fan being positioned opposite the first opening within the body, and the oil cooler being positioned opposite the second opening within the body of the machine. Effect of the Invention

[0007] According to the above configuration, it is possible to efficiently cool devices inside the aircraft, while providing as large a battery unit as possible in a limited space inside the aircraft, thereby increasing the battery capacity. [Brief description of the drawings]

[0008] [Figure 1] 1 is a left side view showing a schematic configuration of a hydraulic excavator, which is an example of an electric working machine according to an embodiment of the present invention. FIG. [Diagram 2] FIG. 2 is a right side view of the hydraulic excavator. [Diagram 3] FIG. 2 is a block diagram showing a schematic configuration of an electrical system and a hydraulic system of the hydraulic excavator. [Figure 4] FIG. 2 is a plan view showing an internal configuration of a first arrangement example in an engine room of the hydraulic excavator. [Diagram 5] FIG. 2 is a rear view showing the internal configuration of the engine room in the first arrangement example. [Figure 6] FIG. 2 is a left side view showing the internal configuration of the engine room in the first arrangement example. [Figure 7] FIG. 2 is a left side view of the hydraulic excavator in which the internal configuration of the engine room is a second arrangement example. [Figure 8] FIG. 2 is a right side view of the hydraulic excavator. [Figure 9]FIG. 4 is a plan view showing the internal configuration of the second arrangement example of the engine room. [Figure 10] FIG. 4 is a rear view showing the internal configuration of the second arrangement example of the engine room. [Figure 11] FIG. 2 is a left side view showing the internal configuration of the second arrangement example of the engine room. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The following describes an embodiment of the present invention with reference to the drawings.

[0010] [1. Electric working machines] FIG. 1 is a left side view showing a schematic configuration of a hydraulic excavator 1 (electric excavator) which is an example of an electric work machine according to an embodiment of the present invention. FIG. 2 is a right side view of the hydraulic excavator 1. The hydraulic excavator 1 comprises a lower traveling body 2, a working machine 3, and an upper rotating body 4 (also called a machine body). In this embodiment, the internal configuration of the upper rotating body 4 (particularly an engine room 44 described later) will be described based on two examples (a first arrangement example and a second arrangement example). Below, the internal configuration of the upper rotating body 4 (the engine room 44) will be described in the first arrangement example.

[0011] Here, the directions are defined as follows. The direction in which the operator (operator, driver) seated in the driver's seat 43a arranged in the control section 43 of the upper rotating body 4 faces forward is defined as "forward," and the opposite direction is defined as "rearward." When the upper rotating body 4 is in a non-rotating state (rotation angle 0 degrees) relative to the lower running body 2, the front-rear direction of the upper rotating body 4 coincides with the front-rear direction of the lower running body 2. In the drawings, the hydraulic excavator 1 is shown in a state in which the upper rotating body 4 is in a non-rotating state relative to the lower running body 2. In addition, the left side as viewed from the operator seated in the driver's seat 43a is defined as "left," and the right side is defined as "right." Furthermore, the direction of gravity perpendicular to the front-rear direction and the left-right direction is defined as the up-down direction, and the upstream side of the direction of gravity is defined as "up," and the downstream side is defined as "down." In the drawings, the front is indicated with the symbol "F," the rear with the symbol "B," the right with the symbol "R," the left with the symbol "L," the up with the symbol "U," and the down with the symbol "D," as necessary.

[0012] The lower traveling structure 2 includes a pair of left and right crawlers 21, a pair of left and right traveling motors 22, and a blade 23. The left and right traveling motors 22 drive the left and right crawlers 21, respectively, to move the hydraulic excavator 1 forward and backward. The traveling motors 22 are configured as hydraulic motors. The blade 23, which performs ground leveling work and the like, is provided on the front side of the lower traveling structure 2. The blade 23 is rotated by a blade cylinder 23a. The blade cylinder 23a is configured as a hydraulic cylinder.

[0013] The work machine 3 includes a boom 31, an arm 32, and a bucket 33. By independently driving the boom 31, the arm 32, and the bucket 33, it is possible to perform work of excavating earth and sand, etc.

[0014] The boom 31 is rotated by a boom cylinder 31a. The boom cylinder 31a has a base end supported on the front part of the upper rotating body 4 and is movable so as to be telescopic. In the drawings, the boom cylinder 31a is arranged so that the rod side is the base end, but it may be arranged so that the tube side is the base end. The arm 32 is rotated by an arm cylinder 32a. The arm cylinder 32a has a base end supported by the boom 31 and is movable so as to be telescopic. The bucket 33 is rotated by a bucket cylinder 33a. The bucket cylinder 33a has a base end supported by the arm 32 and is movable so as to be telescopic. The boom cylinder 31a, the arm cylinder 32a, and the bucket cylinder 33a are each composed of a hydraulic cylinder.

[0015] A base end of the boom 31 is swingably connected to a tip end 41a of a revolving frame 41, which will be described later, via a bracket (not shown). That is, the hydraulic excavator 1 of this embodiment has a boom swing function in which the boom 31 swings left and right from the tip end 41a as a starting point.

[0016] The upper rotating body 4 is located above the lower traveling body 2, and is provided so as to be rotatable relative to the lower traveling body 2 via a swivel bearing (not shown). The upper rotating body 4 includes a swivel frame 41, a swivel motor 42, a control unit 43, and an engine room 44. The upper rotating body 4 rotates relative to the lower traveling body 2 by driving the swivel motor 42 arranged on the swivel frame 41. The swivel frame 41 is constituted by a plurality of metal members joined by welding or the like. The swivel motor 42 is constituted by a hydraulic motor.

[0017] A left bonnet 44L and a right bonnet 44R are provided in the engine room 44, which serve as left and right side walls. The left bonnet 44L is located on the left side (one side) of the engine room 44, and the right bonnet 44R is located on the right side (the other side) of the engine room 44. The left bonnet 44L and the right bonnet 44R are each fixed to the revolving frame 41 via a support member (not shown). A first opening 44L1 of the left bonnet 44L and a second opening 44R1 and a third opening 44R2 of the right bonnet 44R will be described later.

[0018] The engine room 44 houses the battery unit BU and the fan 45. That is, the hydraulic excavator 1 is equipped with the battery unit BU and the fan 45 within the machine body. The battery unit BU is formed of, for example, a lithium ion battery, and stores power for driving the electric motor EM (see FIG. 3). The battery unit BU may be formed by unitizing a plurality of batteries, or may be formed of a single battery cell. In addition, a power feed port (not shown) is provided on the upper rotating body 4. The battery unit BU can be charged by connecting the power feed port to an external power source (not shown).

[0019] The fan 45 is an electric fan, and takes in air (outside air) into the engine room 44. That is, the fan 45 takes in air into the aircraft body. This creates a wind flow in the engine room 44. The fan 45 has a first fan 45a and a second fan 45b. The first fan 45a is located above the second fan 45b. That is, the multiple fans 45 are arranged vertically.

[0020] A hydraulic pump 61 (see FIG. 3) and an oil cooler 46 are further accommodated in the engine room 44. That is, the hydraulic excavator 1 is equipped with the hydraulic pump 61 and the oil cooler 46 within the machine body. The hydraulic pump 61 is driven by an electric motor EM, and supplies hydraulic oil (pressurized oil) to hydraulic motors (e.g., the left and right traveling motors 22, the swing motor 42) and hydraulic cylinders (e.g., the blade cylinder 23a, the boom cylinder 31a, the arm cylinder 32a, the bucket cylinder 33a). The hydraulic motors and hydraulic cylinders that are driven by the supply of hydraulic oil from the hydraulic pump 61 are collectively referred to as hydraulic actuators 63 (see FIG. 3).

[0021] The oil cooler 46 is connected to an oil passage through which the hydraulic oil discharged from the hydraulic pump 61 circulates (see FIG. 3). In the above-mentioned oil passage, the hydraulic oil that has generated heat as the hydraulic actuator 63 is driven flows into the oil cooler 46 via a control valve 62. The oil cooler 46 is configured as a heat exchanger that cools the hydraulic oil by exchanging heat with wind (air) that hits the oil cooler 46. In other words, the oil cooler 46 cools the hydraulic oil that is discharged from the hydraulic pump 61 and generates heat as the hydraulic actuator 63 is driven.

[0022] The control unit 43 is provided on the upper part of the upper rotating body 4. A driver's seat 43a is arranged in the control unit 43. A plurality of control members 43b are arranged around the driver's seat 43a. The plurality of control members 43b include levers, switches, pedals, etc. An operator sits in the driver's seat 43a and operates the plurality of control members 43b to drive the hydraulic actuator 63. This allows the lower traveling body 2 to travel, the blade 23 to perform ground leveling work, the work machine 3 to perform excavation work, the upper rotating body 4 to rotate, etc.

[0023] The hydraulic excavator 1 may be configured to use, as the actuator, a hydraulic actuator 63 in combination with an electric actuator driven by electricity. The electric actuator includes, for example, an electric travel motor, an electric swing motor, and an electric cylinder.

[0024] [2. Electrical and hydraulic system configuration] Fig. 3 is a block diagram showing a schematic configuration of an electric system and a hydraulic system of the hydraulic excavator 1. In Fig. 3, wiring through which an electric signal or current flows is shown by a solid line, and oil paths through which hydraulic oil flows are shown by a dashed line. The hydraulic excavator 1 includes an electric motor EM, a charger 51, an inverter 52, a PDU (Power Drive Unit) 53, a junction box 54, a DC-DC converter 55, a lead battery 56, and a system controller 57. The charger 51, the inverter 52, the PDU 53, the junction box 54, the DC-DC converter 55, and the lead battery 56 are collectively referred to as electrical equipment EQ. The electrical equipment EQ is housed in the engine room 44 (see Fig. 4).

[0025] The electrical equipment EQ is directly connected to the battery unit BU, or is electrically connected to the battery unit BU via another electrical equipment. For example, the PDU 53 as the electrical equipment EQ is directly connected to the battery unit BU. Also, the inverter 52 as the electrical equipment EQ is electrically connected to the battery unit BU via the junction box 54 as another electrical equipment EQ.

[0026] The electric motor EM is driven by electric power supplied from the battery unit BU via a junction box 54 and an inverter 52. The electric motor EM is configured as a synchronous motor, an induction motor, or the like. The electric motor EM is housed in the engine room 44. In other words, the hydraulic excavator 1 is provided with an electric motor EM inside the machine body that is driven by receiving a supply of electric power from the battery unit BU.

[0027] The charger 51 (also called a power supply device) converts the AC voltage supplied from the external power source into a DC voltage. The inverter 52 converts the DC voltage supplied from the battery unit BU into an AC voltage and supplies it to the electric motor EM. This drives the electric motor EM. The supply of the AC voltage from the inverter 52 to the electric motor EM is performed based on a rotation command output from a system controller 57.

[0028] The PDU 53 is a battery control unit that controls an internal battery relay to control input and output of the battery unit BU. The junction box 54 includes a charger relay, an inverter relay, a fuse, etc. The voltage output from the charger 51 is supplied to the battery unit BU via the junction box 54 and the PDU 53. The voltage output from the battery unit BU is supplied to the inverter 52 via the PDU 53 and the junction box 54.

[0029] The DC-DC converter 55 steps down a high-voltage (e.g., 300 V) DC voltage supplied from the battery unit BU via the junction box 54 to a low voltage (e.g., 12 V). The lead battery 56 outputs a low-voltage DC voltage. The low-voltage DC voltage output from the DC-DC converter 55 and the lead battery 56 is supplied to the drive unit of the fans 45 (the first fan 45a and the second fan 45b), the system controller 57, and the like. In this embodiment, a plurality of DC-DC converters 55 are provided (see FIG. 4), but only one may be provided. The system controller 57 is configured by an electronic control unit also called an ECU (Electronic Control Unit). The system controller 57 electrically controls each part of the hydraulic excavator 1.

[0030] A plurality of hydraulic pumps 61 are connected to a rotating shaft (output shaft) of the electric motor EM. The plurality of hydraulic pumps 61 include a variable displacement pump and a fixed displacement pump. FIG. 3 illustrates only one hydraulic pump 61 as an example. Each hydraulic pump 61 is connected to a hydraulic oil tank 64 that stores hydraulic oil. When the hydraulic pump 61 is driven by the electric motor EM, hydraulic oil in the hydraulic oil tank 64 is supplied to the hydraulic actuator 63 via the control valve 62. This drives the hydraulic actuator 63. In other words, the hydraulic actuator 63 is driven by the supply of hydraulic oil by the hydraulic pump 61. The control valve 62 is a directional switching valve that controls the flow direction and flow rate of the hydraulic oil supplied to the hydraulic actuator 63 by the hydraulic pump 61.

[0031] The hydraulic oil discharged from the hydraulic actuator 63 flows into the hydraulic oil tank 64 via the control valve 62 and the oil cooler 46. Therefore, the hydraulic oil that generates heat as the hydraulic actuator 63 is driven is cooled by the oil cooler 46 and then flows into the hydraulic oil tank 64. In this manner, the hydraulic excavator 1 is equipped with the oil cooler 46, the control valve 62, the hydraulic actuator 63, and the hydraulic oil tank 64.

[0032] [3. Internal structure of engine room] The arrangement of each device (e.g., fan 45, oil cooler 46, battery unit BU, etc.) in the engine room 44 will be described with reference to Figs. 4, 5, and 6. Figs. 4, 5, and 6 are a plan view, a rear view, and a left side view showing the internal configuration of the engine room 44. Each device arranged in the engine room 44 is supported on the revolving frame 41 via a support member such as a stay, but in Figs. 4 to 6, the support member is omitted in order to clarify the arrangement position of each device. Also, Figs. 4 and 5 show the left bonnet 44L cut horizontally and vertically at the position of the first opening 44L1 in order to clarify the arrangement position of the fan 45 relative to the first opening 44L1. Similarly, the right bonnet 44R cut horizontally and vertically at the position of the second opening 44R1 in order to clarify the arrangement position of the oil cooler 46 relative to the second opening 44R1.

[0033] As shown in FIG. 4 and FIG. 5, the left bonnet 44L is located on the left side (one side) of the engine room 44. The left bonnet 44L is provided with a first opening 44L1 penetrating in the left-right direction. Two first openings 44L1 are provided corresponding to the first fan 45a and the second fan 45b. The right bonnet 44R is located on the right side (the other side) of the engine room 44. The right bonnet 44R is provided with a second opening 44R1 and a third opening 44R2 penetrating in the left-right direction. In other words, the aircraft (particularly the engine room 44 of the upper rotating body 4) has the first opening 44L1 provided on one side of the aircraft and the second opening 44R1 provided on the other side of the aircraft.

[0034] The third opening 44R2 is located forward of the second opening 44R1. The third opening 44R2 is provided at a position overlapping with a front part BU1 of the battery unit BU when the engine room 44 is viewed from the right. The front part BU1 of the battery unit BU refers to a portion including the frontmost part of the battery unit BU. The range of the front part BU1 in the fore-and-aft direction is not particularly limited, and may be appropriately set within a range forward of the center of the battery unit BU in the fore-and-aft direction.

[0035] In this embodiment, the third opening 44R2 is provided so that the entirety of the third opening 44R2 overlaps with the front part BU1 of the battery unit BU, but the configuration of the third opening 44R2 is not limited to the above configuration. For example, only the rear part of the third opening 44R2 may be provided so as to overlap with the front part BU1. In this manner, the vehicle body has the third opening 44R2 provided on the other lateral side and located forward of the second opening 44R1. And, at least a part of the third opening 44R2 is located so as to overlap with the front part BU1 of the battery unit BU in a side view.

[0036] Fans 45 (first fan 45a and second fan 45b) are disposed inside the engine room 44 (i.e., on the right side) relative to the first opening 44L1 and at a position facing the first opening 44L1. An oil cooler 46 is disposed inside the engine room 44 (i.e., on the left side) relative to the second opening 44R1 and at a position facing the second opening 44R1. That is, the fan 45 is disposed opposite the first opening 44L1 within the aircraft body, and the oil cooler 46 is disposed opposite the second opening 44R1 within the aircraft body.

[0037] When the engine room 44 is viewed from the rear, the battery unit BU is disposed between the fan 45 and the second opening 44R1 (right bonnet 44R). That is, the battery unit BU is disposed between the fan 45 and the second opening 44R1 when viewed from the rear. Three battery units BU are provided and are disposed side by side in the vertical direction.

[0038] Below the battery unit BU, the electric motor EM and the hydraulic oil tank 64 are arranged side by side. The electric motor EM is provided on the left side (one side) of the engine room 44, and the hydraulic oil tank 64 is provided on the right side (the other side) of the engine room 44.

[0039] The oil cooler 46 and a part of the electrical equipment EQ (first electrical equipment EQ1) are arranged behind the battery unit BU. The first electrical equipment EQ1 includes a charger 51, an inverter 52, a DC-DC converter 55, and a lead battery 56. The inverter 52 and the DC-DC converter 55 are arranged to the right of the fan 45. The inverter 52 is located below the DC-DC converter 55. The charger 51 is arranged to the right of the inverter 52 and the DC-DC converter 55. The lead battery 56 is arranged below the charger 51 and shifted to the left of the charger 51. The oil cooler 46 is located to the right of the charger 51. Therefore, the first electrical equipment EQ1 is arranged between the fan 45 and the oil cooler 46 inside the aircraft body.

[0040] As shown in Figures 4 and 6, the rest of the electrical equipment EQ (second electrical equipment EQ2) and the fan 45 are arranged to the left of the battery unit BU. That is, the second electrical equipment EQ2 and the fan 45 are arranged to the side of the battery unit BU. The second electrical equipment EQ2 includes a PDU 53 and a junction box 54. The second electrical equipment EQ2 is located forward of the fan 45. The fan 45 is provided so as to protrude rearward beyond the rear end of the battery unit BU when the engine room 44 is viewed from the left. That is, a part of the fan 45 is located rearward of the battery unit BU in a side view of the aircraft.

[0041] According to the above configuration, when the fan 45 is driven, air is taken in (sucked in) into the aircraft body (particularly the engine room 44 of the upper rotating body 4) through the first opening 44L1. The taken in air flows from the left side (one side) to the right side (the other side) inside the aircraft body, and is discharged through the second opening 44R1. This creates a wind flow from the left side to the right side inside the aircraft body. The above wind cools each device (e.g., the oil cooler 46, the battery unit BU, the electric motor EM, the electrical equipment EQ, etc.) arranged inside the aircraft body. The taken in air is also discharged through the third opening 44R2, but the wind flow toward the third opening 44R2 will be described later.

[0042] As described above, the oil cooler 46 is disposed opposite the second opening 44R1. Therefore, the wind hits the oil cooler 46 last among the devices disposed in the aircraft body. That is, the oil cooler 46 is cooled last among the devices in the aircraft body. Then, the wind (relatively high temperature wind) after cooling the relatively high temperature oil cooler 46 is directly discharged to the outside of the aircraft body from the second opening 44R1. Therefore, the relatively high temperature wind can be discharged to the outside of the aircraft body while preventing the relatively high temperature wind from hitting the battery unit BU, the electric motor EM, and the electrical equipment EQ in the aircraft body. Therefore, each device in the aircraft body can be efficiently cooled. In addition, the fan 45 is disposed close to the left side of the aircraft body, and the oil cooler 46 is disposed close to the right side of the aircraft body. This makes it possible to easily arrange the remaining devices while ensuring as wide an arrangement space for the battery unit BU as possible in the left-right direction (width direction of the aircraft body) in the aircraft body. As a result, it is possible to efficiently cool each device inside the vehicle body, while providing as large a battery unit BU as possible in the limited space inside the vehicle body, thereby increasing the battery capacity.

[0043] When the battery unit BU is disposed between the fan 45 and the second opening 44R1, it becomes easier to expand the arrangement space of the battery unit BU in the left-right direction compared to disposing the battery unit BU between the fan 45 and the oil cooler 46. In other words, it becomes easier to expand the arrangement space of the battery unit BU in the left-right direction at least by the width of the oil cooler 46 in the left-right direction. From this perspective, it is desirable that the battery unit BU be disposed between the fan 45 and the second opening 44R1 in rear view, as in this embodiment.

[0044] By disposing the first electrical equipment EQ1 (e.g., the charger 51) between the fan 45 and the oil cooler 46, it is possible to prevent the wind (relatively high-temperature wind) after cooling the relatively high-temperature oil cooler 46 from hitting the first electrical equipment EQ1. This allows the first electrical equipment EQ1 and the oil cooler 46 inside the machine body to be cooled efficiently. Therefore, in a configuration such as this embodiment in which the hydraulic excavator 1 is provided with electrical equipment EQ connected to the battery unit BU, and the electrical equipment EQ includes the first electrical equipment EQ1 located on the rear side of the machine body relative to the battery unit BU, it is desirable to dispose the first electrical equipment EQ1 between the fan 45 and the oil cooler 46 inside the machine body.

[0045] By arranging the electric motor EM and the hydraulic oil tank 64 side by side below the battery unit BU, it becomes easier to ensure the horizontal arrangement space for the battery unit BU. This makes it easy to provide a battery unit BU that is large in the horizontal direction. Therefore, in a configuration in which the hydraulic excavator 1 further includes the hydraulic oil tank 64 in addition to the electric motor EM, as in this embodiment, it is desirable to arrange the electric motor EM and the hydraulic oil tank 64 side by side below the battery unit BU inside the machine body.

[0046] The electric motor EM is provided on the same side as the fan 45 (one side of the aircraft body), and the hydraulic oil tank 64 is provided on the same side as the oil cooler 46 (the other side of the aircraft body). In this case, below the battery unit BU, the electric motor EM is disposed on the upstream side of the wind flowing from the first opening 44L1 to the second opening 44R1, and the hydraulic oil tank 64 is disposed on the downstream side. In this arrangement, the wind after cooling the electric motor EM hits the hydraulic oil tank 64 and cools the hydraulic oil tank 64. Then, the wind (relatively high temperature wind) after cooling the hydraulic oil tank 64 is discharged outside the aircraft body from the second opening 44R1. In other words, it is possible to prevent the relatively high temperature wind from hitting the electric motor EM. Therefore, the electric motor EM and the hydraulic oil tank 64 are efficiently cooled. From the above viewpoints, it is preferable that the electric motor EM is provided on one side of the aircraft body, and the hydraulic oil tank 64 is provided on the other side of the aircraft body.

[0047] By arranging the multiple fans 45 (the first fan 45a and the second fan 45b) in a vertical line, the range in which the wind flows within the machine body can be expanded in the vertical direction. This allows the electrical equipment EQ that needs to be cooled within the machine body to be arranged in a vertical line, improving the degree of freedom in arranging the electrical equipment EQ. In addition, by arranging the multiple fans 45 in the vertical direction, the diameter of each fan 45 becomes smaller than in a configuration in which one fan is arranged in the same vertical range. This allows the first opening 44L1 facing the fan 45 to be formed with the minimum necessary size, and prevents a decrease in the strength of the machine body (especially the left bonnet 44L). From this perspective, it is desirable to arrange the multiple fans 45 in a vertical line, as in this embodiment.

[0048] By disposing the fan 45 on the side of the battery unit BU (on the left side in this embodiment), the wind blowing from the fan 45 hits the battery unit BU efficiently. This allows the battery unit BU to be cooled efficiently. From this perspective, it is desirable to dispose the fan 45 on the side of the battery unit BU as in this embodiment.

[0049] If a portion of the airflow from the fan 45 flows rearward of the battery unit BU, the first electrical device EQ1 disposed rearward of the battery unit BU is efficiently cooled. From this viewpoint, it is desirable that a portion of the fan 45 is located rearward of the battery unit BU in the airframe in a side view.

[0050] By arranging the oil cooler 46 behind the battery units BU, it becomes easy to provide a battery unit BU that is large in the left-right direction. Also, behind the battery units BU, the wind flowing from the fan 45 efficiently hits the oil cooler 46. This improves the cooling efficiency of the oil cooler 46. From this perspective, it is desirable to arrange the oil cooler 46 behind the battery units BU on the aircraft body, as in this embodiment.

[0051] Here, the flow of wind toward the third opening 44R2 will be described with reference to FIG. 4. The air taken into the engine room 44 from the first opening 44L1 by the fan 45 passes through the engine room 44, and is discharged through the second opening 44R1 and also through the third opening 44R2. As described above, the third opening 44R2 is located forward of the second opening 44R1. Therefore, the air from the first opening 44L1 toward the third opening 44R2 flows from the left side to the right side inside the aircraft body along the side of the battery unit BU (if a plurality of battery units BU are stacked, it passes through the gaps between the upper and lower battery units BU), and flows from the rear side to the front side. This creates a flow of wind that flows from the left side to the right side inside the aircraft body, and from the rear side to the front side.

[0052] As described above, at least a part of the third opening 44R2 is positioned so as to overlap with the front part BU1 of the battery unit BU in a side view. In this case, the wind taken in from the first opening 44L1 flows through the vicinity of the front part BU1 of the battery unit BU and is discharged from the third opening 44R2. Therefore, it is possible to cool the battery unit BU by blowing the wind against the front part BU1 of the battery unit BU. Therefore, from the viewpoint of increasing the cooling efficiency of the battery unit BU, as in this embodiment, it is desirable that the aircraft has the third opening 44R2 provided on the other lateral side and positioned forward of the second opening 44R1, and that at least a part of the third opening 44R2 is positioned so as to overlap with the front part BU1 of the battery unit BU in a side view.

[0053] By arranging the second electrical equipment EQ2 (e.g., PDU 53) in front of the fan 45 and to the side of the battery unit BU (to the left in this embodiment), the wind flowing from the fan 45 toward the third opening 44R2 hits the second electrical equipment EQ2 on the side of the battery unit BU efficiently. This allows the second electrical equipment EQ2 to be efficiently cooled. From the viewpoint of efficiently cooling the second electrical equipment EQ2 while effectively utilizing the empty space on the side of the battery unit BU, it is desirable that the electrical equipment EQ includes the second electrical equipment EQ2 located on the front side of the aircraft body than the fan 45, and that the second electrical equipment EQ2 be arranged on one side of the aircraft body, to the side of the battery unit BU, as in this embodiment.

[0054] [4. Other internal configurations of the engine room] The case where the internal configuration of the engine room 44 is the second arrangement example will be described. Figs. 7 and 8 are left side and right side views of the hydraulic excavator 1 in the above case. Figs. 9, 10, and 11 are plan, rear, and left side views showing the internal configuration of the engine room 44 in the second arrangement example. In Figs. 9 to 11, similar to Figs. 4 to 6, support members such as stays are omitted in order to clarify the arrangement positions of each device (e.g., the fan 45, the oil cooler 46, the battery unit BU, etc.). Also, in Figs. 9 and 10, similar to Figs. 4 and 5, the left bonnet 44L is shown cut horizontally and vertically at the position of the first opening 44L1 in order to clarify the arrangement position of the fan 45 relative to the first opening 44L1. Similarly, the right bonnet 44R is shown cut horizontally and vertically at the position of the second opening 44R1 in order to clarify the arrangement position of the oil cooler 46 relative to the second opening 44R1.

[0055] As shown in Figs. 7 to 11, the left bonnet 44L is provided with a first opening 44L1 penetrating in the left-right direction. A fan 45 is disposed in a position facing the first opening 44L1 in the engine room 44. Here, one fan 45 is provided. The right bonnet 44R is provided with a second opening 44R1 penetrating in the left-right direction. An oil cooler 46 is disposed in a position facing the second opening 44R1 in the engine room 44. A battery unit BU and a third electrical equipment EQ3, which is a part of the electrical equipment EQ, are disposed between the fan 45 and the oil cooler 46. Four battery units BU are provided, and are arranged side by side in the front-rear direction.

[0056] The third electrical equipment EQ3 includes a charger 51, an inverter 52, a PDU 53, and a DC-DC converter 55. The inverter 52 is disposed to the right of the fan 45. The PDU 53 is disposed to the right of the inverter 52. The charger 51 is disposed in front of the PDU 53. The charger 51, the inverter 52, and the PDU 53 are positioned above the battery unit BU. The DC-DC converter 55 is disposed behind the PDU 53 and on the rear side of the battery unit BU. The oil cooler 46 is positioned to the right of the charger 51, the PDU 53, and the DC-DC converter 55. More specifically, the oil cooler 46 is positioned on the right side of the battery unit BU.

[0057] The space below the floor section 43c, which is provided forward of the battery unit BU and below the control section 43, is included inside the engine room 44. The above space accommodates a hydraulic oil tank 64. That is, the hydraulic oil tank 64 is disposed inside the aircraft body, further forward of the battery unit BU. Also, when viewed from the rear side of the aircraft body, the hydraulic oil tank 64 is positioned offset to the left with respect to the battery unit BU.

[0058] A support portion 43b1 for the control member 43b is provided on the front side of the floor portion 43c, and extends upward from the floor portion 43c. A part of the control members 43b is provided on the support portion 43b1. A control valve 62 is accommodated in the support portion 43b1. Therefore, the control valve 62 is located above the hydraulic oil tank 64.

[0059] The remainder of the electrical equipment EQ (fourth electrical equipment EQ4) is disposed behind the hydraulic oil tank 64 and in front of the fan 45. The fourth electrical equipment EQ4 includes a junction box 54 and a lead battery 56. The junction box 54 and the lead battery 56 are disposed side by side on the left of the battery unit BU. The lead battery 56 is located to the left of the junction box 54. An electric motor EM is disposed behind the hydraulic oil tank 64 and below the fan 45.

[0060] As described above, in the second arrangement example, the first opening 44L1 is provided on the left side (one side) of the machine body (particularly the engine room 44 of the upper rotating body 4) and the second opening 44R1 is provided on the right side (the other side) of the machine body, similarly to the first arrangement example. In addition, the fan 45 is disposed in the machine body so as to face the first opening 44L1, and the oil cooler 46 is disposed in the machine body so as to face the second opening 44R1. Therefore, in the second arrangement example, the same effect as in the first arrangement example can be obtained. More specifically, the arrangement space for the battery unit BU can be secured as wide as possible while efficiently cooling each device (e.g., the oil cooler 46, the battery unit BU, the electric motor EM, the electrical equipment EQ, etc.) in the machine body.

[0061] By disposing the battery unit BU between the fan 45 and the oil cooler 46, it is possible to prevent the relatively high-temperature wind that has cooled the oil cooler 46 from hitting the battery unit BU. This allows the battery unit BU and the oil cooler 46 inside the aircraft to be cooled efficiently. Therefore, as in the second arrangement example, the battery unit BU may be disposed between the fan 45 and the oil cooler 46.

[0062] By arranging the third electrical equipment EQ3 (e.g., the charger 51) between the fan 45 and the oil cooler 46, it is possible to prevent the relatively high-temperature air after cooling the oil cooler 46 from hitting the third electrical equipment EQ3. This allows the third electrical equipment EQ3 and the oil cooler 46 inside the machine body to be cooled efficiently. Therefore, in a configuration in which the hydraulic excavator 1 is equipped with electrical equipment EQ, a part of the electrical equipment EQ (the third electrical equipment EQ3) may be arranged between the fan 45 and the oil cooler 46 inside the machine body, as in the second arrangement example.

[0063] By arranging the hydraulic oil tank 64 forward of the battery unit BU, it is easier to ensure vertical arrangement space for the battery unit BU compared to the first arrangement example in which the hydraulic oil tank 64 is arranged below the battery unit BU. This makes it easy to provide a battery unit BU that is large in the vertical direction. Also, the empty space in the machine body forward of the battery unit BU is effectively utilized as arrangement space for the hydraulic oil tank 64. From this perspective, in a configuration in which the hydraulic excavator 1 is provided with the hydraulic oil tank 64, the hydraulic oil tank 64 may be arranged in the machine body forward of the battery unit BU, as in the second arrangement example.

[0064] In this case, if the hydraulic oil tank 64 is arranged offset to the left or right with respect to the battery unit BU, the arrangement space of the battery unit BU can be extended forward, and the capacity of the battery unit BU can be further increased. Also, instead of expanding the arrangement space of the battery unit BU forward, it is possible to arrange other members in the space forward of the battery unit BU. For example, it is possible to arrange a swing cylinder (not shown) that swings the boom 31 (see Figs. 7 and 8) in the space forward of the battery unit BU. Thus, in order to increase the capacity of the battery unit BU or to effectively utilize the space as an arrangement space for other members, it is desirable to arrange the hydraulic oil tank 64 offset to the left or right with respect to the battery unit BU, as in the second arrangement example (leftward in the second arrangement example).

[0065] From the standpoint of effectively utilizing the empty space within the aircraft located rearward of the hydraulic oil tank 64 and below the fan 45, it is desirable to position the electric motor EM rearward of the aircraft from the hydraulic oil tank 64 and below the fan 45, as in the second arrangement example.

[0066] From the standpoint of effectively utilizing the empty space within the aircraft that is located rearward of the hydraulic oil tank 64 and forward of the fan 45, it is desirable to arrange the fourth electrical device EQ4 (e.g., junction box 54) rearward of the aircraft from the hydraulic oil tank 64 and forward of the aircraft from the fan 45, as in the second arrangement example.

[0067] When the control valve 62 is disposed above the hydraulic oil tank 64, even if hydraulic oil leaks from the control valve 62, the leaked hydraulic oil can be prevented from adhering to the battery unit BU. In addition, as shown in Figs. 7 and 8, in a configuration in which the support part 43b1 is located above the hydraulic oil tank 64 via the floor part 43c, a layout in which the control valve 62 is disposed inside the support part 43b1 is possible. In this case, it is easy to realize a small hydraulic excavator 1 of an ultra-small turning type by effectively utilizing the space inside the support part 43b1. Therefore, in a configuration in which the hydraulic excavator 1 includes the control valve 62 in addition to the hydraulic oil tank 64, the control valve 62 may be disposed above the hydraulic oil tank 64 as in the second arrangement example.

[0068] [5. Supplementary Information] In the present embodiment, a configuration including three (first arrangement example) or four (second arrangement example) battery units BU has been described, but the configuration of the battery units BU is not limited to the above. The battery units BU may be configured as large as possible depending on the space available for arranging the battery units BU.

[0069] In this embodiment, a configuration including two (first arrangement example) or one (second arrangement example) fans 45 has been described, but the configuration of the fans 45 is not limited to the above. It is sufficient that the wind (air volume) required for cooling each device (e.g., the oil cooler 46, the battery unit BU, etc.) in the engine room 44 is secured, and the size and number of the fans 45 may be selected according to the required air volume.

[0070] In Figs. 1 and 7, the first opening 44L1 is illustrated as being smaller than the outer diameter of the fan 45 (the first fan 45a and the second fan 45b), but may be formed larger than the outer diameter of the fan 45. Similarly, in Figs. 2 and 8, the second opening 44R1 is illustrated as being smaller than the outer diameter of the oil cooler 46, but may be formed larger than the outer diameter of the oil cooler 46. In addition, a protective member (e.g., louver, mesh, etc.) may be attached to the first opening 44L1, the second opening 44R1, and the third opening 44R2. When the above-mentioned protective member is attached, a part of the opening is blocked by the protective member, so it is desirable to select the size of the opening taking the protective member into consideration.

[0071] In this embodiment, the configuration in which the body (right bonnet 44R) has the third opening 44R2 has been described, but the third opening 44R2 is not essential. Even if the third opening 44R2 is not provided, the air taken into the body from the first opening 44L1 is discharged to the outside of the body from the second opening 44R1. Therefore, the wind still flows from the left side to the right side inside the body. And, the above-mentioned wind still cools each device inside the body (for example, the oil cooler 46, the battery unit BU, etc.). In other words, even in this case, it is possible to obtain the effect of providing as large a battery unit BU as possible in the limited space inside the body while efficiently cooling each device inside the body.

[0072] In this embodiment, the first opening 44L1, the second opening 44R1, and the third opening 44R2 are provided in the engine room 44 so that air flows from the left side to the right side inside the engine room 44, and the fan 45 is provided in a position facing the first opening 44L1 inside the engine room 44, but the arrangement is not limited to this. For example, the openings and the fan 45 may be arranged so that air flows from the right side to the left side inside the engine room 44. In this case, the arrangement of each device (each component) in the engine room 44 is reversed in the left-right direction from this embodiment.

[0073] In this embodiment, the electric work machine has been described taking a hydraulic excavator 1, which is a construction machine, as an example, but the electric work machine is not limited to the hydraulic excavator 1 and may be a construction machine such as a wheel loader. Furthermore, the electric work machine may be an agricultural machine such as a combine harvester or a tractor.

[0074] [6. Notes] The hydraulic excavator 1 described in this embodiment can also be expressed as an electrically powered working machine as described in the following supplementary notes.

[0075] The motorized working machine referred to in Appendix (1) is Inside the aircraft, A battery unit for storing power; an electric motor that is driven by receiving the supply of electric power from the battery unit; a hydraulic pump driven by the electric motor; an oil cooler that cools the hydraulic oil discharged from the hydraulic pump; A fan that takes in air into the aircraft body, The fuselage has a first opening and a second opening, The first opening is provided on one side of the fuselage, The second opening is provided on the other lateral side of the fuselage, The fan is disposed in the airframe opposite the first opening, The oil cooler is disposed inside the aircraft body opposite the second opening.

[0076] The electric working machine of appendix (2) is the electric working machine according to appendix (1), The battery unit is disposed between the fan and the second opening in a rear view.

[0077] The electric working machine of appendix (3) is the electric working machine according to appendix (2), an electrical device connected to the battery unit; the electrical equipment includes a first electrical equipment located in the aircraft body and rearward of the aircraft body relative to the battery unit, The first electrical device is disposed inside the aircraft body, between the fan and the oil cooler.

[0078] The electric working machine of appendix (4) is the electric working machine according to appendix (3), A hydraulic oil tank for storing the hydraulic oil is provided. The electric motor and the hydraulic oil tank are disposed side by side below the battery unit within the aircraft body, The electric motor is provided on the one side of the airframe, The hydraulic oil tank is provided on the other lateral side of the aircraft body.

[0079] The electric working machine of appendix (5) is an electric working machine according to appendix (3) or (4), The fan is disposed to the side of the battery unit.

[0080] The electric working machine of appendix (6) is the electric working machine according to appendix (5), A portion of the fan is located rearward of the airframe relative to the battery unit in a side view.

[0081] The electric working machine of appendix (7) is an electric working machine according to any one of appendixes (3) to (6), The oil cooler is disposed rearward of the aircraft body relative to the battery unit.

[0082] The electric working machine of appendix (8) is an electric working machine according to any one of appendixes (3) to (7), The airframe has a third opening provided on the other side and positioned forward of the second opening, At least a portion of the third opening is positioned to overlap a front portion of the battery unit in a side view.

[0083] The electric working machine of appendix (9) is the electric working machine according to appendix (8), the electrical equipment includes a second electrical equipment located in the airframe and forward of the airframe relative to the fan, The second electrical device is disposed to the side of the battery unit and on the one lateral side of the airframe.

[0084] The electric working machine of appendix (10) is an electric working machine according to any one of appendixes (1) to (9), The fans are arranged in a plurality of vertical directions.

[0085] The electric working machine of appendix (11) is the electric working machine according to appendix (1), The battery unit is disposed between the fan and the oil cooler.

[0086] The electric working machine of appendix (12) is the electric working machine according to appendix (11), an electrical device connected to the battery unit; The electrical equipment includes a third electrical equipment located between the fan and the oil cooler inside the aircraft body.

[0087] The electric working machine of appendix (13) is the electric working machine according to appendix (12), A hydraulic oil tank for storing the hydraulic oil is provided. The hydraulic oil tank is disposed within the aircraft body and further forward of the aircraft body than the battery unit.

[0088] The electric working machine of appendix (14) is the electric working machine according to appendix (13), The hydraulic oil tank is disposed offset to either the left or right with respect to the battery unit.

[0089] The electric working machine of appendix (15) is the electric working machine according to appendix (13) or (14), The electric motor is disposed rearward of the airframe relative to the hydraulic oil tank and below the fan.

[0090] The electric working machine of appendix (16) is an electric working machine according to any one of appendix (13) to (15), The electrical equipment includes a fourth electrical equipment disposed in the aircraft body, The fourth electrical device is located rearward of the airframe relative to the hydraulic oil tank and forward of the airframe relative to the fan.

[0091] The electric working machine of appendix (17) is an electric working machine according to any one of appendix (13) to (16), a hydraulic actuator driven by the hydraulic oil; A control valve for controlling a flow direction and a flow rate of the hydraulic oil supplied from the hydraulic pump to the hydraulic actuator, The control valve is disposed above the hydraulic oil tank.

[0092] Although the embodiment of the present invention has been described above, the scope of the present invention is not limited to this, and the invention can be expanded or modified without departing from the spirit of the invention. [Industrial Applicability]

[0093] The present invention can be used in electric work machines such as construction machines and agricultural machines. [Explanation of symbols]

[0094] 1. Hydraulic excavator (electric work machine) 4. Upper rotating body (aircraft) 44L1 1st opening 44R1 2nd opening 44R2 3rd opening 45 Fans 46 Oil cooler 61 Hydraulic Pump 62 Control valve 63 Hydraulic Actuator 64 Hydraulic Oil Tank BU Battery Unit BU1 Front EM Electric Motor EQ electrical equipment EQ1 First Electrical Equipment EQ2 2nd Electrical Equipment EQ3 3rd electrical equipment EQ4 4th electrical equipment

Claims

1. Inside the aircraft, A battery unit for storing power; an electric motor that is driven by receiving the supply of electric power from the battery unit; a hydraulic pump driven by the electric motor; an oil cooler that cools the hydraulic oil discharged from the hydraulic pump; A fan that takes in air into the aircraft body, The fuselage has a first opening and a second opening, The first opening is provided on one lateral side of the airframe, The second opening is provided on the other lateral side of the fuselage, The fan is disposed in the airframe opposite the first opening, The oil cooler is disposed inside the machine body so as to face the second opening.

2. The electric working machine according to claim 1 , wherein the battery unit is disposed between the fan and the second opening when viewed from behind.

3. an electrical device connected to the battery unit; the electrical equipment includes a first electrical equipment located in the aircraft body and rearward of the aircraft body relative to the battery unit, The electric working machine according to claim 2 , wherein the first electrical device is disposed inside the machine body, between the fan and the oil cooler.

4. A hydraulic oil tank for storing the hydraulic oil is provided. The electric motor and the hydraulic oil tank are disposed side by side below the battery unit within the aircraft body, The electric motor is provided on the one side of the airframe, The electric work machine according to claim 3 , wherein the hydraulic oil tank is provided on the other lateral side of the machine body.

5. The electric work machine according to claim 3 , wherein the fan is disposed to a side of the battery unit.

6. The electric work machine according to claim 5 , wherein a portion of the fan is located rearward of the body relative to the battery unit in a side view.

7. The electric work machine according to claim 3 , wherein the oil cooler is disposed rearward of the machine body relative to the battery unit.

8. The airframe has a third opening provided on the other lateral side and positioned forward of the second opening, The electric working machine according to claim 3 , wherein at least a portion of the third opening is positioned so as to overlap a front portion of the battery unit in a side view.

9. the electrical equipment includes a second electrical equipment located in the airframe and forward of the airframe relative to the fan, The electric working machine according to claim 8 , wherein the second electrical device is disposed to the side of the battery unit and on the one lateral side of the body.

10. The electric working machine according to claim 1 , wherein a plurality of the fans are arranged vertically.

11. The electric working machine according to claim 1 , wherein the battery unit is disposed between the fan and the oil cooler.

12. an electrical device connected to the battery unit; The electric working machine according to claim 11 , wherein the electrical equipment includes a third electrical equipment located inside the machine body between the fan and the oil cooler.

13. A hydraulic oil tank for storing the hydraulic oil is provided. The electric work machine according to claim 12, wherein the hydraulic oil tank is disposed inside the machine body and further forward of the machine body than the battery unit.

14. The electric working machine according to claim 13 , wherein the hydraulic oil tank is disposed offset to either the left or right with respect to the battery unit.

15. The electric work machine according to claim 13, wherein the electric motor is disposed rearward of the machine body relative to the hydraulic oil tank and below the fan.

16. the electrical equipment includes a fourth electrical equipment disposed in the aircraft body, The electric working machine according to claim 13 , wherein the fourth electrical device is located rearward of the machine body relative to the hydraulic oil tank and forward of the machine body relative to the fan.

17. a hydraulic actuator driven by the hydraulic oil; A control valve for controlling a flow direction and a flow rate of the hydraulic oil supplied from the hydraulic pump to the hydraulic actuator, The electric working machine according to any one of claims 13 to 16, wherein the control valve is disposed above the hydraulic oil tank.

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