Electric work machine

Abstract

To provide an electric work machine configured to secure durability of a battery unit, allow installation of a large battery while suppressing increase in height of the body, thereby increasing battery capacity.SOLUTION: A hydraulic excavator as an electric work machine comprises: a body frame located at a bottom part of the body; a hood support part vertically provided in the body frame; a battery unit for storing electric power; an electric motor driven by the power which is supplied from the battery unit; and electrical parts electrically connected to the battery unit. The electrical parts include a first electrical device which is attached, opposite to a side surface of the battery unit, to the hood support part.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] Patent Document 1 discloses an electric working machine that uses an electric motor as a drive source and has a support frame and a standing frame. The support frame is erected on a swivel base and supports an exterior cover. The standing frame is attached to a battery unit and supports electrical equipment (inverter, junction box, converter) above the battery unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-80704 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the configuration of Patent Document 1, the electrical equipment and the battery unit are arranged vertically, so the aircraft tends to be taller in the vertical direction. If the aircraft height increases, the stability of the aircraft may decrease, and the driver's seat may become higher, making it difficult to drive. In addition, if an attempt is made to suppress the increase in the aircraft height in a configuration in which the electrical equipment and the battery unit are arranged vertically, a small battery unit must be installed in the aircraft, making it difficult to increase the battery capacity.

[0005] Furthermore, since the upright frame that supports the electrical equipment is attached to the battery unit, stress caused by the electrical equipment (e.g., the gravity of the electrical equipment) acts on the battery unit via the upright frame, which may result in damage to the battery unit.

[0006] The present invention has been made to solve the above problems, and its object is to provide an electric work machine that can increase the battery capacity by ensuring the durability of the battery unit and enabling the installation of a larger battery unit while minimizing an increase in the height of the machine body. [Means for solving the problem]

[0007] An electric working machine according to one aspect of the present invention comprises a body frame located at the bottom of a body, a bonnet support part erected on the body frame, a battery unit for storing electricity, an electric motor driven by the electricity supplied from the battery unit, and electrical equipment electrically connected to the battery unit, the electrical equipment including a first electrical device attached to the bonnet support part opposite a side surface of the battery unit. Effect of the Invention

[0008] According to the above configuration, the durability of the battery unit can be ensured, and an increase in the height of the aircraft can be suppressed, allowing the installation of a large battery unit, thereby increasing the battery capacity. [Brief description of the drawings]

[0009] [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 block diagram showing a schematic configuration of an electrical system and a hydraulic system of the hydraulic excavator. [Diagram 3] FIG. 2 is a perspective view showing the internal configuration of an engine room provided in an upper rotating body of the hydraulic excavator, as viewed from the left front. [Figure 4] FIG. 2 is a perspective view showing the internal configuration of the engine room from the left rear. [Diagram 5] FIG. 4 is a perspective view showing a configuration of a rear bonnet support portion provided in the engine room, as viewed from the left front. [Figure 6]FIG. 2 is a left side view showing the arrangement of equipment in the engine room. [Figure 7] FIG. 2 is a front view showing the arrangement of the above-mentioned devices. [Figure 8] FIG. 4 is a perspective view showing a mounting configuration of an inverter disposed in the engine room, as viewed from the left front. [Figure 9] FIG. 4 is a left side view showing a support configuration for the battery unit arranged in the engine room. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The following describes an embodiment of the present invention with reference to the drawings.

[0011] [1. Overview of the Electric Working Machine] 1 is a left side view showing a schematic configuration of a hydraulic excavator 1 (electric excavator) which is an example of an electric working machine according to an embodiment of the present invention. The hydraulic excavator 1 includes a lower traveling body 2, a working machine 3, and an upper rotating body 4 (also called a machine body).

[0012] Here, the directions are defined as follows. The direction in which the operator (operator, driver) seated in the driver's seat 44a arranged in the control section 44 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 state where it is not rotating relative to the lower running body 2 (rotation angle of 0 degrees), the front-to-rear direction of the upper rotating body 4 coincides with the front-to-rear direction of the lower running body 2. In the drawings, the hydraulic excavator 1 is shown in a state where the upper rotating body 4 is not rotating relative to the lower running body 2. Also, the left side as viewed from the operator seated in the driver's seat 44a is defined as "left", and the right side is defined as "right". Furthermore, the direction of gravity perpendicular to the front-to-rear direction and the left-to-right direction (also called the width 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, where necessary, forward is indicated with the symbols "F", rear with "B", right with "R", left with "L", upper with "U", and lower with "D".

[0013] 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, 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.

[0014] 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.

[0015] 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.

[0016] The upper rotating body 4 is located above the lower running body 2, and is provided so as to be rotatable relative to the lower running body 2 via a slewing bearing (not shown). The upper rotating body 4 includes a machine body frame 41 (also called a slewing frame), a slewing motor 42, an engine room 43, and a control section 44. The upper rotating body 4 rotates relative to the lower running body 2 by being driven by the slewing motor 42 arranged on the machine body frame 41. The slewing motor 42 is composed of a hydraulic motor.

[0017] The machine body frame 41 is provided at the bottom of the upper rotating body 4. The machine body frame 41 is composed of cast members extending in the horizontal direction, but is not limited to this and may be composed of, for example, a plurality of metal members joined by welding or the like. The lower surface 41D of the machine body frame 41 is included in the bottom surface portion 4D of the upper rotating body 4. In the upper rotating body 4, the portion including the bottom surface portion 4D is called the bottom portion 4a of the upper rotating body 4. Therefore, the machine body frame 41 is located at the bottom portion 4a of the upper rotating body 4.

[0018] The engine room 43 is provided with a rear bonnet member 43B, a left bonnet member 43L, a right bonnet member (not shown), and an upper wall portion 45. The rear bonnet member 43B forms a side wall on the rear side of the engine room 43. The rear bonnet member 43B is formed of a metal plate-shaped member.

[0019] The left bonnet member 43L and the right bonnet member described above constitute the left and right side walls of the engine room 43. The left bonnet member 43L is fixed to the aircraft frame 41 and a rear bonnet support part 103 (see FIG. 4), which will be described later. The right bonnet member is also fixed to the aircraft frame 41 and the rear bonnet support part 103. The left bonnet member 43L and the right bonnet member are fixed to the aircraft frame 41 via a support member (not shown). The left bonnet member 43L and the right bonnet member are made of a metal plate-shaped member.

[0020] The upper wall portion 45 constitutes an upper wall of the engine room 43. The upper wall portion 45 is made of a metal plate-shaped member. The upper wall portion 45 is connected to a front bonnet support portion 102 (see FIG. 3) and a rear bonnet support portion 103 (see FIG. 4), which will be described later.

[0021] The rear bonnet member 43B, the left bonnet member 43L, the right bonnet member, and the upper wall portion 45 constitute the exterior portion 4c of the upper rotating body 4. The exterior portion 4c also includes the aircraft frame 41. The exterior portion 4c constitutes the outer peripheral surface of the upper rotating body 4. In the upper rotating body 4, the inner portion separated by the exterior portion 4c is called the interior 4e of the upper rotating body 4 (see FIG. 3). The interior 4e of the upper rotating body 4 includes the space inside the engine room 43. The side of the exterior portion 4c opposite the interior 4e of the upper rotating body 4 (i.e., the outer portion separated by the exterior portion 4c) is called the exterior of the upper rotating body 4 (not shown).

[0022] A battery unit BU (also referred to as a high-voltage battery) and a hydraulic pump 61 (see FIG. 2) are housed in the engine room 43. That is, the hydraulic excavator 1 is provided with the battery unit BU and the hydraulic pump 61 inside 4e of the upper rotating body 4. The battery unit BU is formed of, for example, a lithium-ion battery, and stores power for driving the electric motor EM (see FIG. 2). 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).

[0023] The hydraulic pump 61 is driven by an electric motor EM and discharges hydraulic oil. The hydraulic oil (pressurized oil) is supplied to hydraulic motors (e.g., the left and right travel 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. 2).

[0024] The control unit 44 is provided on the upper part of the upper rotating body 4. A driver's seat 44a is arranged in the control unit 44. The driver's seat 44a is fixed to the upper surface of the upper wall portion 45. A plurality of control members 44b are arranged around the driver's seat 44a. The plurality of control members 44b include levers, switches, pedals, etc. An operator sits on the driver's seat 44a and operates the plurality of control members 44b 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.

[0025] The hydraulic excavator 1 may be configured to use both the hydraulic actuator 63 and an electric actuator driven by electricity as the actuator. Also, the hydraulic excavator 1 may be configured to include only the above-mentioned electric actuator as the actuator. The electric actuator includes, for example, an electric travel motor, an electric swing motor, and an electric cylinder.

[0026] [2. Electrical and hydraulic system configuration] Fig. 2 is a block diagram showing a schematic configuration of an electrical system and a hydraulic system of the hydraulic excavator 1. In Fig. 2, wiring through which an electrical signal or current flows is shown by solid lines, and oil paths through which hydraulic oil flows are shown by dashed lines.

[0027] 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 low-voltage 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, the low-voltage battery 56, and the system controller 57 are collectively referred to as electrical equipment EP. The electrical equipment EP is accommodated in the engine room 43 (see FIGS. 3 and 4). That is, the hydraulic excavator 1 includes the electrical equipment EP in the interior 4e of the upper rotating body 4.

[0028] The electrical equipment EP includes a first electrical equipment E1, a second electrical equipment E2, a third electrical equipment E3, and a fourth electrical equipment E4. More specifically, the first electrical equipment E1, the second electrical equipment E2, the third electrical equipment E3, and the fourth electrical equipment E4 are each configured to include a part of the electrical equipment EP. For example, the first electrical equipment E1 includes a charger 51. The second electrical equipment E2 includes a system controller 57. The third electrical equipment E3 includes a junction box 54. The fourth electrical equipment E4 includes a DC-DC converter 55.

[0029] The electric equipment EP is electrically connected to the battery unit BU. That is, each device included in the electric equipment EP is directly connected to the battery unit BU, or is electrically connected to the battery unit BU via another device included in the electric equipment EP. For example, the PDU 53 included in the electric equipment EP is directly connected to the battery unit BU. Also, the inverter 52 included in the electric equipment EP is electrically connected to the battery unit BU via a junction box 54, which is another device included in the electric equipment EP.

[0030] The electric motor EM is driven by 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 accommodated in the engine room 43 (see FIG. 4). That is, the hydraulic excavator 1 includes the electric motor EM in the interior 4e of the upper rotating body 4.

[0031] 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 drive command output from a system controller 57.

[0032] 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.

[0033] The DC-DC converter 55 (also simply called a converter) steps down a high voltage (e.g., 48 V) direct current voltage supplied from the battery unit BU via the junction box 54 to a low voltage (e.g., 12 V). The low-voltage battery 56 is formed of, for example, a lead battery. The low-voltage battery 56 is connected to the DC-DC converter 55 and stores the power that is stepped down and output by the DC-DC converter 55. Therefore, the low-voltage battery 56 outputs a voltage lower than that of the battery unit BU.

[0034] The low DC voltage output from the DC-DC converter 55 and the low-voltage battery 56 is supplied to a system controller 57, a drive section for a fan 71 (see FIG. 3) described later, and the like. The system controller 57 is configured as an electronic control unit also called an ECU (Electronic Control Unit). The system controller 57 electrically controls each section of the hydraulic excavator 1.

[0035] 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. In FIG. 2, only one hydraulic pump 61 is illustrated as an example. Each hydraulic pump 61 is connected to a hydraulic oil tank 65 that stores hydraulic oil. When the hydraulic pump 61 is driven by the electric motor EM, the hydraulic oil in the hydraulic oil tank 65 is supplied to the hydraulic actuator 63 via the control valve 62. This drives the hydraulic actuator 63. 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.

[0036] A heat exchanger 64 (also called an oil cooler) is provided in an oil passage connecting the control valve 62 and the hydraulic oil tank 65. Hydraulic oil that has generated heat as the hydraulic actuator 63 is driven flows into the heat exchanger 64 via the control valve 62. The heat exchanger 64 cools the hydraulic oil by exchanging heat with air (wind) that hits the heat exchanger 64. In other words, the heat exchanger 64 cools the hydraulic oil that is discharged from the hydraulic pump 61 and generates heat as the hydraulic actuator 63 is driven.

[0037] [3. Internal structure of engine room] 3 and 4 are perspective views from the left front and left rear showing the internal configuration of the engine room 43. The engine room 43 has a bonnet support part 101. That is, the hydraulic excavator 1 is equipped with the bonnet support part 101. The bonnet support part 101 supports the rear bonnet member 43B (see FIG. 1), the left bonnet member 43L (see FIG. 1), and the right bonnet member. The bonnet support part 101 is configured to include an upper wall part 45, a front bonnet support part 102, and a rear bonnet support part 103.

[0038] As shown in FIG. 3, the front bonnet support part 102 is disposed on the front side of the engine room 43. The front bonnet support part 102 has a vertical plate 102a and a mounting plate 102b. The vertical plate 102a is formed by bending an upper end of a metal plate-shaped member extending in the vertical direction obliquely backward and a lower end forward. The upper end of the vertical plate 102a is joined to the front end of the upper wall part 45 by welding. The lower end of the vertical plate 102a is connected to the support pillar part 104 by a fastening member such as a bolt. The support pillar part 104 is a support member whose lower end part 104a is connected to the aircraft frame 41. Therefore, the vertical plate 102a is provided upright with respect to the aircraft frame 41 via the support pillar part 104.

[0039] The mounting plate 102b is formed by bending forward the left and right ends of a metal plate-shaped member extending in the left-right direction. Each bent end is connected to the rear surface of the vertical plate 102a. The mounting plate 102b is provided with a plurality of mounting holes (not shown) penetrating in the front-rear direction. The second electrical device E2 (system controller 57) is disposed in front of the mounting plate 102b. The second electrical device E2 is fixed to the mounting holes by fastening members such as bolts. Therefore, the second electrical device E2 is attached to the bonnet support portion 101 (particularly the front bonnet support portion 102). The vertical plate 102a is provided with a through-hole portion (not shown) penetrating in the front-rear direction at a position corresponding to the second electrical device E2.

[0040] As shown in Fig. 4, the rear bonnet support part 103 is disposed on the rear side of the engine room 43. The configuration of the rear bonnet support part 103 will be described with reference to Fig. 5. Fig. 5 is a perspective view from the left front showing the configuration of the rear bonnet support part 103. The rear bonnet support part 103 has an upper plate part 103a, a left side plate part 103b, a left bottom plate part 103c, a left stay 103d, a right side plate part 103e, a right bottom plate part 103f, a right stay 103g, and a reinforcing plate 103h.

[0041] The upper plate portion 103a is located above the rear bonnet support portion 103, and is made of a metal plate-like member extending in the left-right direction. The upper plate portion 103a is joined to the upper wall portion 45 (see FIG. 4) by welding. The left side plate portion 103b is connected to the left end portion of the upper plate portion 103a and extends downward from the left end portion. The left side plate portion 103b has a lower end portion connected to the left bottom plate portion 103c. The left bottom plate portion 103c is made of a plate-like member extending in the horizontal direction. The left bottom plate portion 103c is provided with a plurality of first through holes H1 that penetrate in the up-down direction.

[0042] A left stay 103d is located on the left side of the left side plate portion 103b. The left stay 103d is provided so as to protrude leftward from the left side surface of the left side plate portion 103b. The tip portion (left end portion) of the left stay 103d is bent forward. The left bonnet member 43L (see FIG. 1) is fixed to the left stay 103d.

[0043] The right side plate portion 103e is connected to the right end of the upper plate portion 103a and extends downward from the right end. The lower end of the right side plate portion 103e is connected to the right bottom plate portion 103f. The right bottom plate portion 103f is formed of a plate-like member extending in the horizontal direction. The right bottom plate portion 103f is provided with a plurality of second through holes H2 that penetrate in the vertical direction.

[0044] A right stay 103g is located on the right side of the right side plate portion 103e. The right stay 103g protrudes rightward from the right side surface of the right side plate portion 103e. The right bonnet member is fixed to the right stay 103g.

[0045] A reinforcing plate 103h is provided below the upper plate portion 103a and between the left plate portion 103b and the right plate portion 103e in the left-right direction. The reinforcing plate 103h is configured as a plate-like member having a substantially inverted U-shape when viewed from the front. The configuration of the reinforcing plate 103h is not limited to the above, and may be configured as a simple flat plate, for example. The reinforcing plate 103h is disposed with an inclination along one direction. The above-mentioned one direction is a direction in which the upper side is inclined forward with respect to the up-down direction. The reinforcing plate 103h is joined to the upper plate portion 103a, the left plate portion 103b, and the right plate portion 103e by welding. The reinforcing plate 103h improves the rigidity of the rear bonnet support portion 103 (particularly the rigidity in the left-right direction).

[0046] The reinforcing plate 103h is provided with a plurality of fixing holes 103h1. The fixing holes 103h1 penetrate in a direction in which the front side is inclined downward with respect to the front-rear direction. A first electrical device E1 (charger 51) is disposed on the rear surface (surface facing diagonally upward) of the reinforcing plate 103h (see also FIG. 4). The first electrical device E1 is fixed to the fixing holes 103h1 by fastening members such as bolts. Thus, the first electrical device E1 is attached to the bonnet support portion 101 (particularly the rear bonnet support portion 103).

[0047] As shown in Fig. 4, bolts B1 are inserted into the first through-hole H1 and the second through-hole H2 (both see Fig. 5) of the rear bonnet support part 103, and screwed into threaded parts (not shown) of the vehicle frame 41. This fixes the rear bonnet support part 103 to the vehicle frame 41. In particular, the rear bonnet support part 103 has a left side plate part 103b and a right side plate part 103e that stand upright relative to the vehicle frame 41. Note that the above-mentioned "screwed engagement" refers to joining a member having a male thread by meshing it with a member having a female thread.

[0048] As described above, the bonnet support part 101 has members (the vertical plate 102a of the front bonnet support part 102, and the left side plate part 103b and the right side plate part 103e of the rear bonnet support part 103) that are provided upright with respect to the vehicle frame 41. Therefore, it can be said that the bonnet support part 101 is provided upright on the vehicle frame 41.

[0049] In addition to the left bonnet member 43L, a fourth electrical device E4 (DC-DC converter 55) is also fixed to the left stay 103d of the rear bonnet support portion 103. More specifically, the fourth electrical device E4 is disposed in front of the left stay 103d. A support bracket 105 is attached to the rear surface of the fourth electrical device E4. The support bracket 105 is made of a metal plate-like member extending in the vertical direction, and is connected to the tip portion (left end portion) of the left stay 103d. Therefore, the fourth electrical device E4 is attached to the bonnet support portion 101 (particularly the left stay 103d of the rear bonnet support portion 103) via the support bracket 105.

[0050] Next, the arrangement of the equipment (e.g., battery unit BU, electric motor EM, electrical equipment EP, etc.) within the internal configuration of the engine room 43 will be described with reference to Figs. 6 and 7. Figs. 6 and 7 are a left side view and a front view showing the arrangement of the equipment within the engine room 43. Each piece of equipment arranged within the engine room 43 is supported on the aircraft frame 41 via a support member such as a stay (see Figs. 3 and 4), but in Figs. 6 and 7, the support members are omitted in order to clarify the arrangement position of each piece of equipment. Also, for convenience, Fig. 6 omits the illustration of an air guide section 72, which is shown in Fig. 7 and will be described later.

[0051] As shown in Fig. 6, the first electrical equipment E1 (charger 51) is disposed on the rear side of the engine room 43. As described above, the first electrical equipment E1 is attached to the reinforcing plate 103h of the rear bonnet support portion 103 (see Fig. 5). Since the reinforcing plate 103h is inclined along the above-mentioned one direction (a direction in which the upper side is inclined forward with respect to the vertical direction), the first electrical equipment E1 is also disposed at an incline along the one direction.

[0052] The battery unit BU is disposed in front of the first electrical equipment E1. That is, the first electrical equipment E1 is located on one side (rear) of the battery unit BU in the front-rear direction. The battery unit BU has a rectangular box-like outer shape (see also FIG. 7). The battery unit BU has a side surface BU1, an upper surface BU2, and a lower surface BU3. The side surface BU1 includes a left surface BU1a, a right surface BU1b (see FIG. 7), a front surface BU1c, and a rear surface BU1d. In particular, the first electrical equipment E1 is disposed in a position facing the rear surface BU1d. Therefore, the first electrical equipment E1 faces the side surface BU1 (particularly the rear surface BU1d) of the battery unit BU.

[0053] According to the above configuration, for example, compared to a configuration in which the first electrical device E1 (the charger 51 in this embodiment) is arranged vertically next to the battery unit BU, the height of the body can be lowered while increasing the height of the battery unit BU (while keeping the installation area of ​​the battery unit BU constant). Therefore, the battery capacity can be increased while suppressing an increase in the height of the body.

[0054] Furthermore, as described above, since the first electrical device E1 is attached to the bonnet support portion 101, there is no need to prepare a mounting member (a mounting member dedicated to mounting the first electrical device E1) separate from the bonnet support portion 101. This allows the first electrical device E1 to be attached with a reduced number of parts. Therefore, the reduced number of parts makes it possible to expand the arrangement space for the battery unit BU. This also makes it possible to install a large (large-capacity) battery unit BU.

[0055] The bonnet support 101 is provided on the vehicle frame 41, that is, on a member different from the battery unit BU, and the first electrical equipment E1 is attached to the bonnet support 101. Therefore, even in a layout in which the first electrical equipment E1 is disposed facing the side surface BU1 (the rear surface BU1d in this embodiment) of the battery unit BU, there is no risk of stress caused by the first electrical equipment E1 (for example, the gravity of the first electrical equipment E1 or the tensile stress due to the gravity) acting on the battery unit BU. As a result, it is possible to reduce the risk of the battery unit BU being damaged by external stress, and it is possible to ensure the durability of the battery unit BU. As a result, it is possible to ensure the durability of the battery unit BU, and to increase the battery capacity by enabling the installation of a large battery unit BU while suppressing an increase in the height of the vehicle body.

[0056] In particular, from the standpoint of expanding the placement space for the battery unit BU in the width direction (left-right direction) of the aircraft body, it is desirable to place the first electrical equipment E1 on one side in the fore-and-aft direction (rearward in this embodiment) of the battery unit BU, as in this embodiment.

[0057] In this embodiment, as shown in FIG. 6, the second electrical device E2 (system controller 57) is disposed on the opposite side of the battery unit BU from the first electrical device E1 (that is, in front of the battery unit BU).

[0058] With this arrangement, even if the electrical equipment EP includes the second electrical equipment E2 in addition to the first electrical equipment E1, a tall (large in the vertical direction) battery unit BU is provided while keeping the height of the vehicle body low. As described above, the second electrical equipment E2 is attached to the bonnet support portion 101 (see FIG. 3), so there is no need to prepare a mounting member (a dedicated mounting member for mounting the second electrical equipment E2) other than the bonnet support portion 101. This reduces the number of parts required for mounting the second electrical equipment E2. Therefore, even if the electrical equipment EP includes the second electrical equipment E2, the following configuration is desirable from the viewpoint of increasing the battery capacity while suppressing an increase in the height of the vehicle body with a small number of parts. That is, as in this embodiment, it is desirable that the second electrical equipment E2 is disposed on the other side in the front-rear direction (front in this embodiment) of the battery unit BU and attached to the bonnet support portion 101.

[0059] The electric motor EM is disposed at a position facing the underside BU3 of the battery unit BU. Therefore, the electric motor EM is located below the battery unit BU. That is, the electric motor EM is located closer to the bottom 4a (see FIG. 1) of the vehicle body than the battery unit BU. In addition, an inverter 52 is disposed behind the electric motor EM at a position facing the electric motor EM. That is, the inverter 52 is located on one side (rear) of the electric motor EM in the front-to-rear direction. In addition, the inverter 52 faces the electric motor EM.

[0060] The inverter 52 is supported by the vehicle frame 41 (see FIG. 4). More details are as follows. FIG. 8 is a perspective view from the left front showing the mounting configuration of the inverter 52. A first mounting bracket 111 is provided in front of the inverter 52. The first mounting bracket 111 is formed by bending a lower end 111a of a metal plate-like member extending in the vertical direction forward. The lower end 111a of the first mounting bracket 111 is connected to the vehicle frame 41. The inverter 52 is fixed to the rear surface portion of the first mounting bracket 111 by a fastening member such as a bolt. Therefore, the inverter 52 is mounted to the vehicle frame 41 by the first mounting bracket 111. That is, the inverter 52 is supported by the vehicle frame 41 via the first mounting bracket 111.

[0061] In this configuration (the arrangement of the electric motor EM and the inverter 52), it is easier to reduce the size of the vehicle in the horizontal direction compared to, for example, a layout in which the electric motor EM and the inverter 52 are arranged side by side horizontally with the battery unit BU. Also, when the inverter 52 is attached to the vehicle frame 41, the inverter 52 is located at the bottom 4a of the vehicle (see FIG. 8). As described above, the electric motor EM is located closer to the bottom 4a of the vehicle (than the battery unit BU). Therefore, with this configuration (the configuration in which the inverter 52 is attached to the vehicle frame 41), it is easy to arrange the inverter 52 opposite the electric motor EM.

[0062] Even if the electrical equipment EP is configured to include the inverter 52, it is desirable to easily realize a configuration suitable for a small (small turning radius type) hydraulic excavator 1. From this viewpoint, it is desirable that, as in this embodiment, the electric motor EM is disposed below the battery unit BU, and the inverter 52 is attached to the machine frame 41 facing the electric motor EM.

[0063] If the inverter 52 is disposed rearward of the electric motor EM, the inverter 52 can be easily disposed on the rear side of the engine room 43. This makes it easier to access the inverter 52 from the rear of the aircraft. Therefore, from the viewpoint of shortening the work time (improving work efficiency) in maintenance work on the inverter 52, it is desirable to dispose the inverter 52 on one side in the fore-and-aft direction with respect to the electric motor EM (i.e., the same side in the fore-and-aft direction as the side on which the first electrical device E1 is disposed with respect to the battery unit BU), as in this embodiment.

[0064] 6, the third electrical device E3 (junction box 54) is disposed below the first electrical device E1 and above the inverter 52. Therefore, the first electrical device E1, the third electrical device E3, and the inverter 52 are located in this order from the top.

[0065] In this arrangement, the empty space between the first electrical equipment E1 and the inverter 52 is effectively utilized as an arrangement space for the third electrical equipment E3. Even if the electrical equipment EP includes the third electrical equipment E3 in addition to the first electrical equipment E1 and the inverter 52, it is desirable to arrange the third electrical equipment E3 efficiently (compactly) in the engine room 43. From this viewpoint, it is desirable to position the third electrical equipment E3 between the first electrical equipment E1 and the inverter 52, as in this embodiment.

[0066] The fourth electrical device E4 (DC-DC converter 55) and the low-voltage battery 56 are disposed to the left of the battery unit BU. The low-voltage battery 56 is positioned below the fourth electrical device E4 and shifted forward relative to the fourth electrical device E4. In other words, the fourth electrical device E4 is positioned above the low-voltage battery 56.

[0067] In this arrangement, it is easier to reduce the size of the machine body in the front-rear direction compared to a configuration in which, for example, the fourth electrical equipment E4 is arranged side by side with the battery unit BU in the front-rear direction. Also, as described above, since the fourth electrical equipment E4 is attached to the bonnet support part 101 (see FIG. 4), it is not necessary to prepare a mounting member (a mounting member dedicated to mounting the fourth electrical equipment E4) separate from the bonnet support part 101. This reduces the number of parts when mounting the fourth electrical equipment E4. Therefore, when the electrical equipment EP includes the fourth electrical equipment E4, the following configuration is preferable from the viewpoint of easily realizing a configuration suitable for a small (small turning type) hydraulic excavator 1 with a small number of parts when the electrical equipment EP includes the fourth electrical equipment E4. That is, as in this embodiment, it is preferable that the fourth electrical equipment E4 is arranged on one side (left side in this embodiment) in the width direction of the machine body with respect to the battery unit BU and attached to the bonnet support part 101.

[0068] When the fourth electrical equipment E4 and the low-voltage battery 56 are arranged together to the left of the battery unit BU, it becomes easy to simultaneously access the fourth electrical equipment E4 and the low-voltage battery 56 from the left. This shortens the work time when performing maintenance on the fourth electrical equipment E4 and the low-voltage battery 56 simultaneously. Furthermore, when the low-voltage battery 56, which is relatively heavy among the electrical equipment EP, is arranged as low as possible, the center of gravity of the vehicle is lowered. Therefore, from the viewpoint of improving the work efficiency of the maintenance work and stabilizing the vehicle, it is preferable that the low-voltage battery 56 is arranged on the one side of the battery unit BU and the fourth electrical equipment E4 is arranged above the low-voltage battery 56, as in this embodiment.

[0069] A fan 71 is disposed forward of the fourth electrical equipment E4 and the low-voltage battery 56. The fan 71 is an electric fan, and is driven by low-voltage power supplied from the DC-DC converter 55 and the low-voltage battery 56. When the fan 71 is driven, air (outside air) is sucked (taken in) into the engine room 43. This creates a flow of air (wind) in the engine room 43. More specifically, a first opening (not shown) is provided in the exterior part 4c (see FIG. 1, e.g., the machine frame 41) of the upper rotating body 4. In addition, a second opening 43L2 is provided in the left bonnet member 43L included in the exterior part 4c (see FIG. 1). The air flows into the engine room 43 from the first opening and is discharged from the second opening 43L2.

[0070] As shown in FIG. 7, the fan 71 includes a first fan 71a and a second fan 71b arranged side by side in the vertical direction. The first fan 71a is located below the second fan 71b. A heat exchanger 64 is arranged to the left of the first fan 71a and facing the first fan 71a. The heat exchanger 64 and the fan 71 (the first fan 71a and the second fan 71b) are arranged in the air guide section 72 (see also FIGS. 3 and 4). The air guide section 72 is made of a hollow metal member extending in the left-right direction. The left side of the air guide section 72 is entirely open. The right side of the air guide section 72 is partially open. The air guide section 72 forms a flow path for air flowing in the engine room 43. The air guide section 72 is arranged to the left of the battery unit BU and the electric motor EM. The hydraulic pump 61 is arranged to the right of the electric motor EM.

[0071] Next, the support structure of the battery unit BU will be described with reference to Fig. 9. Fig. 9 is a left side view showing the support structure of the battery unit BU. For convenience, Fig. 9 omits illustration of the fourth electrical device E4, the low-voltage battery 56, the left side plate portion 103b of the rear bonnet support portion 103, etc.

[0072] A battery support plate 121 is provided in the engine room 43. That is, the hydraulic excavator 1 includes the battery support plate 121 in the interior 4e of the upper rotating body 4. The battery support plate 121 is configured of a metal plate-shaped member extending horizontally. The battery support plate 121 is disposed below the first electrical equipment E1 (charger 51). The battery support plate 121 is also disposed above the inverter 52.

[0073] The front side of the battery support plate 121 is supported by the support pillar 104 via the vibration-isolating member 122. The vibration-isolating member 122 is configured to include an elastic body (e.g., rubber). As described above, the support pillar 104 is connected to the vehicle frame 41 (see FIG. 3). The rear side of the battery support plate 121 is supported by the vehicle frame 41 via the vibration-isolating member 122.

[0074] The battery unit BU is installed on the battery support plate 121. More specifically, the battery unit BU is arranged with a lower surface BU3 (see FIG. 6) in contact with an upper surface 121U (see FIG. 4) of the battery support plate 121. The battery unit BU is fixed to the upper surface 121U of the battery support plate 121 by fastening members such as bolts. Therefore, the battery support plate 121 supports the battery unit BU from below.

[0075] The third electrical equipment E3 (junction box 54) is attached to the rear side of the battery support plate 121 (particularly the upper surface 121U) via the second mounting bracket 123. More specifically, the second mounting bracket 123 is provided in front of the third electrical equipment E3. The second mounting bracket 123 is configured by bending forward the upper and lower ends of a metal plate-shaped member extending in the vertical direction. The lower end of the second mounting bracket 123 is fixed to the battery support plate 121 by a fastening member such as a bolt. The battery unit BU is located in front of the second mounting bracket 123. The upper end of the second mounting bracket 123 is connected to the rear surface BU1d (see FIG. 6) of the battery unit BU. The third electrical equipment E3 is fixed to the rear surface of the second mounting bracket 123 by a fastening member such as a bolt.

[0076] In this configuration, the battery support plate 121 is effectively used as a mounting member for the third electrical equipment E3. As a result, when mounting the third electrical equipment E3, it is not necessary to prepare a mounting member (a mounting member dedicated to mounting the third electrical equipment E3) other than the battery support plate 121, and the number of parts is reduced. In addition, the battery support plate 121 is located between the first electrical equipment E1 and the inverter 52 in the up-down direction. Therefore, when the third electrical equipment E3 is mounted on the battery support plate 121, the third electrical equipment E3 is located between the first electrical equipment E1 and the inverter 52. Therefore, from the viewpoint of reliably arranging the third electrical equipment E3 between the first electrical equipment E1 and the inverter 52 with a small number of parts and efficiently arranging the third electrical equipment E3 in the engine room 43, the following configuration is desirable. That is, in a configuration in which the hydraulic excavator 1 is provided with a battery support plate 121 that supports the battery unit BU from below, as in this embodiment, it is desirable that the third electrical device E3 be attached to the battery support plate 121.

[0077] [4. Supplementary Information] In the present embodiment, the battery unit BU has a rectangular box-like outer shape, but the outer shape of the battery unit BU is not limited to the above. The battery unit BU may be configured as large as possible, and may be configured with a part of its outer shape protruding, for example.

[0078] In this embodiment, a configuration has been described in which the first electrical device E1 (charger 51) faces the rear surface BU1d of the battery unit BU, but the first electrical device E1 only needs to face a side surface BU1 of the battery unit BU, and is not limited to the rear surface BU1d. For example, the first electrical device E1 may face the front surface BU1c of the battery unit BU. The first electrical device E1 may also face the left surface BU1a of the battery unit BU. Furthermore, the first electrical device E1 may face the right surface BU1b of the battery unit BU.

[0079] Note that the above "facing" is not limited to facing each other completely directly ahead (i.e., facing each other directly). For example, in this embodiment, the first electrical device E1 is arranged at an incline along the one direction mentioned above (a direction in which the upper side inclines forward relative to the up-down direction). Therefore, the first electrical device E1 is also inclined with respect to the side surface BU1 (the rear surface BU1d in this embodiment) of the battery unit BU (see FIG. 6). Even with this configuration, as long as the first electrical device E1 faces (faces) the side surface BU1, the effect of this embodiment can be obtained (by attaching the first electrical device E1 to the bonnet support portion 101).

[0080] 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.

[0081] [5. 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.

[0082] The motorized working machine referred to in Appendix (1) is An aircraft frame located at the bottom of the aircraft; a bonnet support portion provided upright on the aircraft frame; A battery unit for storing power; an electric motor driven by the power supplied from the battery unit; an electrical component electrically connected to the battery unit, The electrical equipment includes a first electrical device attached to the bonnet support portion opposite a side surface of the battery unit.

[0083] The electric working machine of appendix (2) is the electric working machine according to appendix (1), The first electrical device is disposed on one side of the battery unit in a front-rear direction of the vehicle body.

[0084] The electric working machine of appendix (3) is the electric working machine according to appendix (2), The electrical equipment includes a second electrical device attached to the bonnet support portion on the other side in the front-rear direction relative to the battery unit.

[0085] The electric working machine of appendix (4) is an electric working machine according to appendix (2) or (3), The electric motor is disposed below the battery unit, The electrical equipment includes an inverter that is attached to the vehicle frame opposite the electric motor.

[0086] The electric working machine of appendix (5) is the electric working machine according to appendix (4), The inverter is disposed on the one side in the front-rear direction with respect to the electric motor.

[0087] The electric working machine of appendix (6) is the electric working machine according to appendix (5), The electrical equipment includes a third electrical device located between the first electrical device and the inverter.

[0088] The electric working machine of appendix (7) is the electric working machine according to appendix (6), a battery support plate that supports the battery unit from below; The third electrical device is attached to the battery support plate.

[0089] The electric working machine of appendix (8) is an electric working machine according to any one of appendix (1) to (7), The electrical equipment includes a fourth electrical device attached to the bonnet support portion on one lateral side in a width direction of the vehicle body relative to the battery unit.

[0090] The electric working machine of appendix (9) is the electric working machine according to appendix (8), the electrical equipment includes a low-voltage battery that outputs a lower voltage than the battery unit, the low-voltage battery is disposed on the one side with respect to the battery unit; The fourth electrical device is disposed above the low-voltage battery.

[0091] 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]

[0092] The present invention can be used in electric work machines such as construction machines and agricultural machines. [Explanation of symbols]

[0093] 1. Hydraulic excavator (electric work machine) 4. Upper rotating body (aircraft) 4a bottom 41 Aircraft frame 52 Inverter (Electrical equipment) 56 Low voltage battery (electrical equipment) 101 Bonnet support 121 Battery support plate BU Battery Unit BU1 Side E1 First Electrical Equipment (Electrical Equipment) E2 Second electrical equipment (electrical equipment) E3 Third electrical equipment (electrical equipment) E4 4th electrical equipment (electrical equipment) EM Electric Motor EP Electrical Equipment

Claims

1. An aircraft frame located at the bottom of the aircraft; a bonnet support portion provided upright on the aircraft frame; A battery unit for storing power; an electric motor driven by the power supplied from the battery unit; an electrical component electrically connected to the battery unit, The electric working machine, wherein the electrical equipment includes a first electrical device attached to the bonnet support portion opposite a side surface of the battery unit.

2. The electric working machine according to claim 1 , wherein the first electrical device is disposed on one side in a front-rear direction of the body with respect to the battery unit.

3. The electric working machine according to claim 2 , wherein the electrical equipment includes a second electrical device attached to the bonnet support portion on the other side in the front-rear direction relative to the battery unit.

4. The electric motor is disposed below the battery unit, The electric working machine according to claim 2 , wherein the electrical equipment includes an inverter mounted on the machine frame opposite the electric motor.

5. The electric working machine according to claim 4 , wherein the inverter is disposed on the one side in the front-rear direction with respect to the electric motor.

6. The electric working machine according to claim 5 , wherein the electrical equipment includes a third electrical device located between the first electrical device and the inverter.

7. a battery support plate that supports the battery unit from below; The electric working machine according to claim 6 , wherein the third electrical device is attached to the battery support plate.

8. The electric working machine according to claim 1 , wherein the electrical equipment includes a fourth electrical device attached to the bonnet support portion on one lateral side in a width direction of the machine body relative to the battery unit.

9. the electrical equipment includes a low-voltage battery that outputs a lower voltage than the battery unit, the low-voltage battery is disposed on the one side with respect to the battery unit; The electric working machine according to claim 8 , wherein the fourth electrical device is disposed above the low-voltage battery.

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