Electric work machine

Abstract

Provided is an electric working machine in which the durability of a battery cell can be ensured, an increase in the height of the machine body can be suppressed, and a large battery cell can be provided to increase the battery capacity. A hydraulic shovel, which is an electric working machine, is provided with: a machine body frame positioned at the bottom of a machine body; the engine cover supporting part is vertically arranged on the machine body frame; a battery unit storing power; an electric motor driven by power supplied from the battery unit; and an electrical device electrically connected to the battery cell. The electric device includes a first electric device that faces a side surface of the battery unit and is attached to the hood support portion.

Description

Technical Field

[0001] The present invention relates to an electric working machine. Background Art

[0002] Patent Document 1 discloses an electric working machine that uses an electric motor as a drive source and has a support frame and an upright frame. The support frame is erected on a rotary base plate and supports an outer cover. The upright frame is mounted on a battery unit and supports electrical components (inverter, junction box, converter) above the battery unit.

[0003] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2021-80704

[0004] However, in the structure of Patent Document 1, since the electrical components and the battery unit are arranged side by side in the vertical direction, the height of the machine body tends to increase in the vertical direction. If the height of the machine body increases, there is a concern that the stability of the machine body may decrease, and there is also a concern that the driver's seat may become higher and it may become difficult to drive. In addition, in the structure in which the electrical components and the battery unit are arranged side by side in the vertical direction, if it is desired to suppress the increase in the height of the machine body, it is necessary to mount a small battery unit on the machine body, and it is difficult to increase the battery capacity.

[0005] Moreover, since the upright frame that supports the electrical components is mounted on the battery unit, stress (such as the gravity of the electrical components) caused by the electrical components acts on the battery unit via the upright frame. As a result, there is a concern that the battery unit may be damaged. Summary of the Invention

[0006] The present invention has been completed to solve the above problems, and an object thereof is to provide an electric working machine that can ensure the durability of a battery unit, can suppress an increase in the height of the machine body, and can provide a larger battery unit to increase the battery capacity.

[0007] An electric working machine according to one aspect of the present invention includes: a machine body frame located at the bottom of the machine body; an engine hood support portion erected on the machine body frame; a battery unit that stores electric power; an electric motor that is driven by the electric power supplied from the battery unit; and electrical components electrically connected to the battery unit, the electrical components including a first electrical device that faces a side surface of the battery unit and is mounted on the engine hood support portion.

[0008] According to the above structure, it is possible to ensure the durability of the battery unit, suppress an increase in the height of the machine body, and provide a larger battery unit to increase the battery capacity. Brief Description of the Drawings

[0009] Figure 1It is a left view showing a schematic structure of a hydraulic excavator, which is an example of an electric working machine according to an embodiment of the present invention.

[0010] Figure 2 It is a block diagram schematically showing the structures of the electrical system and the hydraulic system of the above hydraulic excavator.

[0011] Figure 3 It is a perspective view observed from the left front showing the internal structure of an engine room provided in the upper revolving body of the above hydraulic excavator.

[0012] Figure 4 It is a perspective view observed from the left rear showing the internal structure of the above engine room.

[0013] Figure 5 It is a perspective view observed from the left front showing the structure of a rear engine hood support portion provided in the above engine room.

[0014] Figure 6 It is a left view showing the arrangement of the equipment in the above engine room.

[0015] Figure 7 It is a front view showing the arrangement of the above equipment.

[0016] Figure 8 It is a perspective view observed from the left front showing the mounting structure of an inverter arranged in the above engine room.

[0017] Figure 9 It is a left view showing the support structure of a battery unit arranged in the above engine room.

[0018] Explanation of Reference Numerals

[0019] 1... Hydraulic excavator (electric working machine); 4... Upper revolving body (machine body); 4a... Bottom; 41... Machine body frame; 52... Inverter (electrical device); 56... Low-voltage battery (electrical device); 101... Engine hood support portion; 121... Battery support plate; BU... Battery unit; BU1... Side surface; E1... First electrical equipment (electrical device); E2... Second electrical equipment (electrical device); E3... Third electrical equipment (electrical device); E4... Fourth electrical equipment (electrical device); EM... Electric motor; EP... Electrical device. Detailed Embodiment

[0020] Embodiments of the present invention will be described below with reference to the drawings.

[0021] 〔1. Schematic Structure of Electric Working Machine〕

[0022] Figure 1The left view shows the schematic structure 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 revolving body 4 (also referred to as a machine body).

[0023] Here, the directions are defined as follows. The direction in which the operator (operator, driver) sitting on the driver's seat 44a arranged in the control section 44 of the upper revolving body 4 faces forward is defined as "front", and the opposite direction is defined as "rear". In a state where the upper revolving body 4 does not revolve relative to the lower traveling body 2 (when the revolving angle is 0 degrees), the front-rear direction of the upper revolving body 4 coincides with the front-rear direction of the lower traveling body 2. In the drawings, the hydraulic excavator 1 is shown in a state where the upper revolving body 4 does not revolve relative to the lower traveling body 2. In addition, from the perspective of the operator sitting on the driver's seat 44a, the left side is defined as "left" and the right side is defined as "right". And, the direction of gravity perpendicular to the front-rear direction and the left-right direction (also referred to as the width direction) is defined as the up-down direction, the upstream side of the direction of gravity is defined as "up", and the downstream side is defined as "down". In the drawings, as needed, the symbol "F" is used to represent the front, the symbol "B" is used to represent the rear, the symbol "R" is used to represent the right side, the symbol "L" is used to represent the left side, the symbol "U" is used to represent the upper side, and the symbol "D" is used to represent the lower side.

[0024] The lower traveling body 2 includes a pair of left and right crawlers 21, a pair of left and right traveling motors 22, and a bulldozer blade 23. The left and right traveling motors 22 can drive the left and right crawlers 21 respectively to move the hydraulic excavator 1 forward and backward. The traveling motor 22 is composed of a hydraulic motor. The bulldozer blade 23 for performing land leveling work is provided on the front side of the lower traveling body 2. The bulldozer blade 23 is rotated by a bulldozer blade cylinder 23a. The bulldozer blade cylinder 23a is composed of a hydraulic cylinder.

[0025] The working 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, excavation work such as sand and soil can be performed.

[0026] The boom 31 is rotated by a boom cylinder 31a. The base end portion of the boom cylinder 31a is supported on the front portion of the upper revolving body 4, and the boom cylinder 31a is movable in a telescopic manner. In the drawings, the boom cylinder 31a is arranged such that the piston rod side becomes the base end portion, but it may also be arranged such that the cylinder barrel side becomes the base end portion. The arm 32 is rotated by an arm cylinder 32a. The base end portion of the arm cylinder 32a is supported on the boom 31, and the arm cylinder 32a is movable in a telescopic manner. The bucket 33 is rotated by a bucket cylinder 33a. The base end portion of the bucket cylinder 33a is supported on the arm 32, and the bucket cylinder 33a is movable in a telescopic manner. The boom cylinder 31a, the arm cylinder 32a, and the bucket cylinder 33a are each composed of a hydraulic cylinder.

[0027] The upper revolving body 4 is located above the lower traveling body 2 and is configured to be rotatable relative to the lower traveling body 2 via a slewing bearing (not shown). The upper revolving body 4 includes a body frame 41 (also referred to as a slewing frame), a slewing motor 42, an engine room 43, and an operation unit 44. The upper revolving body 4 rotates relative to the lower traveling body 2 by driving the slewing motor 42 disposed on the body frame 41. The slewing motor 42 is constituted by a hydraulic motor.

[0028] The body frame 41 is disposed at the lower part of the upper revolving body 4. The body frame 41 is constituted by a cast member extending in the horizontal direction, but is not limited thereto. For example, it may also be a structure including a plurality of metal members joined by welding or the like. The lower surface 41D of the body frame 41 is included in the bottom surface portion 4D of the upper revolving body 4. The portion of the upper revolving body 4 including the bottom surface portion 4D is referred to as the bottom 4a of the upper revolving body 4. Therefore, the body frame 41 is located at the bottom 4a of the upper revolving body 4.

[0029] In the engine room 43, a rear engine hood member 43B, a left engine hood member 43L, a right engine hood member (not shown), and an upper wall portion 45 are provided. The rear engine hood member 43B constitutes the side wall on the rear side of the engine room 43. The rear engine hood member 43B is constituted by a plate-like member made of metal.

[0030] The left engine hood member 43L and the above-mentioned right engine hood member constitute the left and right side walls of the engine room 43. The left engine hood member 43L is fixed to the body frame 41 and a rear engine hood support portion 103 (see Figure 4 ). The right engine hood member is also fixed to the body frame 41 and the rear engine hood support portion 103. The left engine hood member 43L and the right engine hood member are fixed to the body frame 41 via a support member (not shown). The left engine hood member 43L and the right engine hood member are constituted by plate-like members made of metal.

[0031] The upper wall portion 45 constitutes the upper side wall of the engine room 43. The upper wall portion 45 is constituted by a plate-like member made of metal. The upper wall portion 45 is connected to a front engine hood support portion 102 (see Figure 3 ) and a rear engine hood support portion 103 (see Figure 4 ).

[0032] The rear engine hood member 43B, the left engine hood member 43L, the right engine hood member, and the upper wall portion 45 constitute the exterior portion 4c of the upper revolving body 4. The exterior portion 4c further includes the body frame 41. The outer peripheral surface of the upper revolving body 4 is constituted by the exterior portion 4c. In the upper revolving body 4, the inner portion separated by the exterior portion 4c is referred to as the interior 4e of the upper revolving body 4 (see Figure 3)。The interior 4e of the upper revolving body 4 includes the space inside the engine room 43. The side opposite to the interior 4e of the upper revolving body 4 with respect to the exterior part 4c (i.e., the outer part separated by the exterior part 4c) is referred to as the exterior of the upper revolving body 4 (not shown).

[0033] The battery unit BU (also referred to as the high-voltage battery) and the hydraulic pump 61 are housed in the engine room 43 (see Figure 2 ). That is, the hydraulic excavator 1 has the battery unit BU and the hydraulic pump 61 inside the interior 4e of the upper revolving body 4. The battery unit BU is constituted by, for example, a lithium-ion battery and stores the electric power for driving the electric motor EM (see Figure 2 ). The battery unit BU can be constituted by unitizing a plurality of battery units or can be constituted by a single cell. In addition, a power supply port (not shown) is provided on the upper revolving body 4. By connecting the above power supply port and an external power source (not shown), the battery unit BU can be charged.

[0034] The hydraulic pump 61 is driven by the electric motor EM and discharges the working oil. The above working oil (pressure oil) is supplied to the hydraulic motors (such as the left and right traveling motors 22 and the swing motor 42) and the hydraulic cylinders (such as the blade cylinder 23a, the boom cylinder 31a, the arm cylinder 32a, and the bucket cylinder 33a). The hydraulic motors and the hydraulic cylinders that are supplied with the working oil from the hydraulic pump 61 and are driven are collectively referred to as the hydraulic actuators 63 (see Figure 2 ).

[0035] The operation part 44 is provided on the upper part of the upper revolving body 4. The driver's seat 44a is arranged on the operation part 44. The driver's seat 44a is fixed to the upper surface part of the upper wall part 45. A plurality of operation members 44b are arranged around the driver's seat 44a. The plurality of operation members 44b are configured to include levers, switches, pedals, etc. By an operator sitting on the driver's seat 44a and operating the plurality of operation members 44b, the hydraulic actuators 63 are driven. Thereby, the traveling of the lower traveling body 2, the land leveling operation by means of the blade 23, the excavation operation by means of the working machine 3, the swing of the upper revolving body 4, etc. can be performed.

[0036] The hydraulic excavator 1 may also be configured to use both the hydraulic actuators 63 and the electric actuators driven by electricity as the actuators. In addition, the hydraulic excavator 1 may also be configured to have only the above electric actuators as the actuators. The electric actuators include, for example, an electric traveling motor, an electric swing motor, and an electric cylinder.

[0037] 〔2. Structure of the electrical system and the hydraulic system〕

[0038] Figure 2 is a block diagram schematically showing the structure of the electrical system and the hydraulic system of the hydraulic excavator 1. In addition, Figure 2The wiring for the power supply signal or current flow is shown by a solid line, and the oil passage for the working oil flow is shown by a dashed line.

[0039] 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 the electrical components EP. The electrical components EP are housed in the engine room 43 (refer to Figure 3 and Figure 4 ). That is, the hydraulic excavator 1 has the electrical components EP inside the upper swing body 4 at 4e.

[0040] In addition, the electrical components EP include a first electrical device E1, a second electrical device E2, a third electrical device E3, and a fourth electrical device E4. More specifically, the first electrical device E1, the second electrical device E2, the third electrical device E3, and the fourth electrical device E4 are each configured to include a part of the electrical components EP. For example, the first electrical device E1 includes the charger 51. The second electrical device E2 includes the system controller 57. The third electrical device E3 includes the junction box 54. The fourth electrical device E4 includes the DC-DC converter 55.

[0041] The electrical components EP are electrically connected to the battery unit BU. That is, each device included in the electrical components EP is directly connected to the battery unit BU, or is electrically connected to the battery unit BU via other devices included in the electrical components EP. For example, the PDU 53 included in the electrical components EP is directly connected to the battery unit BU. In addition, the inverter 52 included in the electrical components EP is electrically connected to the battery unit BU via the junction box 54, which is other equipment included in the electrical components EP.

[0042] The electric motor EM is driven by the electric power supplied from the battery unit BU via the junction box 54 and the inverter 52. The electric motor EM is composed of a synchronous motor, an induction motor, or the like. The electric motor EM is housed in the engine room 43 (refer to Figure 4 ). That is, the hydraulic excavator 1 has the electric motor EM inside the upper swing body 4 at 4e.

[0043] The charger 51 (also called a power supply) converts the AC voltage supplied from the above external power supply 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. Thereby, the electric motor EM is driven. The supply of the AC voltage from the inverter 52 to the electric motor EM is performed based on the drive command output from the system controller 57.

[0044] The PDU 53 is a battery control unit that controls the internal battery relay and the input / output of the battery unit BU. The junction box 54 is configured to include 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. In addition, the voltage output from the battery unit BU is supplied to the inverter 52 via the PDU 53 and the junction box 54.

[0045] The DC-DC converter 55 (also simply referred to as a converter) steps down the high-voltage (e.g., 48V) DC voltage supplied from the battery unit BU via the junction box 54 to a low voltage (e.g., 12V). The low-voltage battery 56 is composed of, for example, a lead battery. The low-voltage battery 56 is connected to the DC-DC converter 55 and stores the power 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.

[0046] The low-voltage DC voltage output from the DC-DC converter 55 and the low-voltage battery 56 is supplied to the system controller 57, the drive unit of the fan 71 (to be described later) (refer to Figure 3 ). The system controller 57 is composed of an electronic control unit also known as an ECU (Electronic Control Unit). The system controller 57 performs electrical control of each part of the hydraulic excavator 1.

[0047] A plurality of hydraulic pumps 61 are connected to the 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. Figure 2 In, only one hydraulic pump 61 is shown as an example. Each hydraulic pump 61 is connected to a work oil tank 65 that stores work oil. When the hydraulic pump 61 is driven by the electric motor EM, the work oil in the work oil tank 65 is supplied to the hydraulic actuator 63 via the control valve 62. Thereby, the hydraulic actuator 63 is driven. The control valve 62 is a direction switching valve that controls the flow direction and flow rate of the work oil supplied to the hydraulic actuator 63.

[0048] A heat exchanger 64 (also called an oil cooler) is provided in the oil passage connected to the control valve 62 and the work oil tank 65. The work oil heated along with the driving of the hydraulic actuator 63 flows into the heat exchanger 64 via the control valve 62. The heat exchanger 64 cools the work oil by exchanging heat with the air (wind) blown onto the heat exchanger 64. That is, the heat exchanger 64 cools the work oil discharged from the hydraulic pump 61 and heated due to the driving of the hydraulic actuator 63.

[0049] 〔3. Internal Structure of the Engine Room〕

[0050] Figure 3 and Figure 4It is a perspective view of the internal structure of the engine compartment 43 as viewed from the left front and a perspective view as viewed from the left rear. The engine compartment 43 has a hood support portion 101. That is, the hydraulic excavator 1 is provided with the hood support portion 101. The hood support portion 101 supports the rear hood member 43B (refer to Figure 1 ), the left hood member 43L (refer to Figure 1 ), and the above-mentioned right hood member. The hood support portion 101 is configured to include an upper wall portion 45, a front hood support portion 102, and a rear hood support portion 103.

[0051] As Figure 3 shown, the front hood support portion 102 is disposed on the front side of the engine compartment 43. The front hood support portion 102 has a vertical plate 102a and a mounting plate 102b. The vertical plate 102a is formed by bending the upper end portion of a metal plate-like member extending in the vertical direction obliquely rearward and bending the lower end portion forward. The upper end portion of the vertical plate 102a is joined to the front end portion of the upper wall portion 45 by welding. The lower end portion of the vertical plate 102a is connected to the support column portion 104 by fastening members such as bolts. The lower end portion 104a of the support column portion 104 is a support member connected to the body frame 41. Therefore, the vertical plate 102a is erected on the body frame 41 via the support column portion 104.

[0052] The mounting plate 102b is formed by bending the left and right end portions of a metal plate-like member extending in the left-right direction forward. The bent end portions are connected to the rear surface portion of the vertical plate 102a. A plurality of mounting holes (not shown) penetrating in the front-rear direction are provided in the mounting plate 102b. The second electrical equipment E2 (system controller 57) is disposed in front of the mounting plate 102b. The second electrical equipment E2 is fixed to the above-mentioned mounting holes by fastening members such as bolts. Therefore, the second electrical equipment E2 is mounted on the hood support portion 101 (particularly, the front hood support portion 102). In addition, a through hole portion (not shown) penetrating in the front-rear direction is provided in the vertical plate 102a at a position corresponding to the second electrical equipment E2.

[0053] As Figure 4 shown, the rear hood support portion 103 is disposed on the rear side of the engine compartment 43. Based on Figure 5 the structure of the rear hood support portion 103 will be described. Figure 5 It is a perspective view of the structure of the rear hood support portion 103 as viewed from the left front. The rear hood support portion 103 has an upper plate portion 103a, a left side plate portion 103b, a left bottom plate portion 103c, a left stay 103d, a right side plate portion 103e, a right bottom plate portion 103f, a right stay 103g, and a reinforcing plate 103h.

[0054] The upper plate portion 103a is located above the rear hood support portion 103 and is composed of a plate-like member made of metal extending in the left-right direction. The upper plate portion 103a is joined to the upper wall portion 45 (see Figure 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 lower end portion of the left side plate portion 103b is connected to the left bottom plate portion 103c. The left bottom plate portion 103c is composed of a plate-like member extending in the horizontal direction. A plurality of first through holes H1 penetrating in the up-down direction are provided in the left bottom plate portion 103c.

[0055] The left stay 103d is located on the left side of the left side plate portion 103b. The left stay 103d is provided to protrude leftward from the left side surface of the left side plate portion 103b. The front end portion (left end portion) of the left stay 103d is bent forward. The left hood member 43L (see Figure 1 ) is fixed to the left stay 103d.

[0056] The right side plate portion 103e is connected to the right end portion of the upper plate portion 103a and extends downward from the right end portion. The lower end portion of the right side plate portion 103e is connected to the right bottom plate portion 103f. The right bottom plate portion 103f is composed of a plate-like member extending in the horizontal direction. A plurality of second through holes H2 penetrating in the up-down direction are provided in the right bottom plate portion 103f.

[0057] The right stay 103g is located on the right side of the right side plate portion 103e. The right stay 103g is provided to protrude rightward from the right side surface of the right side plate portion 103e. The above-mentioned right hood member is fixed to the right stay 103g.

[0058] A reinforcing plate 103h is provided below the upper plate portion 103a and between the left side plate portion 103b and the right side plate portion 103e in the left-right direction. The reinforcing plate 103h is composed of a plate-like member having a substantially inverted U shape when viewed from the front. The structure of the reinforcing plate 103h is not limited to the above structure, and for example, it may also be composed of a simple flat plate. The reinforcing plate 103h is arranged to be inclined along one direction. The above-mentioned one direction is the 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 side plate portion 103b, and the right side plate portion 103e by welding. Through the reinforcing plate 103h, the rigidity (especially the rigidity in the left-right direction) of the rear hood support portion 103 is improved.

[0059] A plurality of fixing holes 103h1 are provided in the reinforcing plate 103h. The fixing holes 103h1 penetrate in a direction inclined downward with respect to the front-rear direction on the front side. The first electrical device E1 (charger 51) is arranged on the rear surface (the surface facing obliquely upward) side of the reinforcing plate 103h (see also Figure 4)。The first electrical device E1 is fixed relative to the fixing hole 103h1 by fastening components such as bolts. Therefore, the first electrical device E1 is installed on the engine hood support portion 101 (specifically, the rear engine hood support portion 103).

[0060] As Figure 4 shown, bolts B1 are respectively inserted into the first through hole H1 and the second through hole H2 of the rear engine hood support portion 103 (both refer to Figure 5 ), and are screwed with the threaded portion (not shown) of the body frame 41. Thus, the rear engine hood support portion 103 is fixed to the body frame 41. In particular, the left side plate portion 103b and the right side plate portion 103e of the rear engine hood support portion 103 are erected relative to the body frame 41. In addition, the above-mentioned screwing means that a component with an external thread and a component with an internal thread are engaged and combined.

[0061] As described above, the engine hood support portion 101 has components erected relative to the body frame 41 (the longitudinal plate 102a of the front engine hood support portion 102, the left side plate portion 103b and the right side plate portion 103e of the rear engine hood support portion 103). Therefore, it can be said that the engine hood support portion 101 is erected on the body frame 41.

[0062] In addition, on the left brace 103d of the rear engine hood support portion 103, in addition to the left engine hood component 43L, the fourth electrical device E4 (DC-DC converter 55) is also fixed. More specifically, the fourth electrical device E4 is disposed in front of the left brace 103d. A support bracket 105 is installed on the rear surface portion of the fourth electrical device E4. The support bracket 105 is composed of a metal plate-like component extending in the vertical direction and is connected to the front end portion (left end portion) of the left brace 103d. Therefore, the fourth electrical device E4 is installed on the engine hood support portion 101 (specifically, the left brace 103d of the rear engine hood support portion 103) via the support bracket 105.

[0063] Next, based on Figure 6 and Figure 7 , the internal structure of the engine compartment 43, especially the arrangement of devices (such as battery unit BU, electric motor EM, electrical device EP, etc.) will be described. Figure 6 and Figure 7 are a left view and a front view showing the arrangement of devices in the engine compartment 43. Each device disposed in the engine compartment 43 is supported on the body frame 41 via support components such as braces (refer to Figure 3 and Figure 4 ), and in Figure 6 and Figure 7 , for the sake of clarity of the arrangement positions of each device, the illustration of the support components is omitted. In addition, in Figure 6 , for convenience, Figure 7Illustration of the aforementioned air guiding portion 72 shown in the figure.

[0064] As Figure 6 shown, the first electrical device E1 (charger 51) is arranged on the rear side of the engine compartment 43. As described above, the first electrical device E1 is mounted on the reinforcement plate 103h of the rear engine hood support portion 103 (refer to Figure 5 ). Since the reinforcement plate 103h is inclined along the aforementioned one direction (the direction in which the upper side is inclined forward with respect to the vertical direction), the first electrical device E1 is also arranged to be inclined along one direction.

[0065] The battery unit BU is arranged in front of the first electrical device E1. That is, the first electrical device E1 is located on one side (rear side) in the front-rear direction with respect to the battery unit BU. The battery unit BU has a rectangular box shape (also refer to Figure 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 (refer to Figure 7 ), a front surface BU1c, and a rear surface BU1d. In particular, the first electrical device E1 is arranged at a position opposite to the rear surface BU1d. Therefore, the first electrical device E1 faces the side surface BU1 (especially the rear surface BU1d) of the battery unit BU.

[0066] According to the above structure, for example, compared with a structure in which the first electrical device E1 (the charger 51 in the present embodiment) and the battery unit BU are arranged side by side in the vertical direction, the body height can be reduced, and (when the installation area of the battery unit BU remains unchanged), the height of the battery unit BU can be increased. Therefore, an increase in the body height can be suppressed and the battery capacity can be increased.

[0067] In addition, as described above, since the first electrical device E1 is mounted on the engine hood support portion 101, there is no need to prepare mounting components other than the engine hood support portion 101 (special mounting components for mounting the first electrical device E1). Thus, the first electrical device E1 can be mounted with a smaller number of components. Therefore, the arrangement space for the battery unit BU can be expanded corresponding to the smaller number of components. In this regard, a larger (high-capacity) battery unit BU can also be provided.

[0068] The engine hood support portion 101 is provided on the body frame 41, that is, a component different from the battery unit BU, and the first electrical device E1 is mounted on the engine hood support portion 101. Therefore, even in a layout where the first electrical device E1 is disposed opposite to the side surface BU1 (the rear surface BU1d in the present embodiment) of the battery unit BU, there is no concern that stress caused by the first electrical device E1 (for example, the gravity of the first electrical device E1 or tensile stress caused by the above gravity) acts on the battery unit BU. As a result, the concern about damage to the battery unit BU due to external stress can be reduced, and the durability of the battery unit BU can be ensured. Thus, the durability of the battery unit BU can be ensured, the increase in the body height can be suppressed, and a larger battery unit BU can be provided to increase the battery capacity.

[0069] In particular, from the viewpoint of expanding the arrangement space of the battery unit BU in the width direction (left - right direction) of the body, it is preferable that, as in the present embodiment, the first electrical device E1 is arranged on one side in the front - rear direction (the rear side in the present embodiment) with respect to the battery unit BU.

[0070] In the present embodiment, as Figure 6 shown, the second electrical device E2 (system controller 57) is arranged on the side opposite to the first electrical device E1 with respect to the battery unit BU (that is, at a position in front of the battery unit BU).

[0071] In such an arrangement, even in a structure where the electrical device EP includes, in addition to the first electrical device E1, the second electrical device E2, the body height can be reduced, and a battery unit BU with a higher height (larger in the up - down direction) can be provided. Further, as described above, the second electrical device E2 is mounted on the engine hood support portion 101 (refer to Figure 3 ), so there is no need to prepare mounting components other than the engine hood support portion 101 (dedicated mounting components for mounting the second electrical device E2). Thus, the number of components for mounting the second electrical device E2 can be reduced. Therefore, even in a structure where the electrical device EP includes the second electrical device E2, from the viewpoints of fewer component numbers, suppressing the increase in the body height, and increasing the battery capacity, the following structure is preferable. That is, it is preferable that, as in the present embodiment, the second electrical device E2 is arranged on the other side in the front - rear direction (the front side in the present embodiment) with respect to the battery unit BU and is mounted on the engine hood support portion 101.

[0072] The electric motor EM is arranged at a position opposite to the lower surface 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 of the body than the battery unit BU (refer to Figure 1) position. Further, behind the electric motor EM, an inverter 52 is disposed at a position facing the electric motor EM. That is, the inverter 52 is located on one side (rear side) in the front-rear direction with respect to the electric motor EM. Further, the inverter 52 is opposed to the electric motor EM.

[0073] In addition, the inverter 52 is supported by the body frame 41 (see Figure 4 ). More specifically, as follows. Figure 8 is a perspective view of the mounting structure of the inverter 52 as viewed from the left front. A first mounting bracket 111 is provided in front of the inverter 52. The first mounting bracket 111 is formed by bending the lower end portion 111a of a metal plate-like member extending in the vertical direction forward. The lower end portion 111a of the first mounting bracket 111 is connected to the body frame 41. The inverter 52 is fixed to the rear surface portion of the first mounting bracket 111 by fastening members such as bolts. Therefore, the inverter 52 is mounted on the body frame 41 through the first mounting bracket 111. That is, the inverter 52 is supported by the body frame 41 via the first mounting bracket 111.

[0074] In this structure (the arrangement structure of the electric motor EM and the inverter 52), for example, compared with a layout in which the electric motor EM, the inverter 52, and the battery unit BU are arranged side by side in the horizontal direction, it is easy to reduce the body size in the horizontal direction. Further, when the inverter 52 is mounted on the body frame 41, the inverter 52 is located at the bottom 4a of the body (see Figure 8 ). As described above, the electric motor EM is located at a position closer to the bottom 4a of the body (than the battery unit BU). Therefore, in this structure (the structure in which the inverter 52 is mounted on the body frame 41), it is easy to arrange the inverter 52 opposite to the electric motor EM.

[0075] Even in a structure in which the electrical device EP includes the inverter 52, it is preferable to easily realize a structure suitable for the small (small swing type) hydraulic excavator 1. From this viewpoint, it is preferable that, as in the present embodiment, the electric motor EM is disposed below the battery unit BU, and the inverter 52 is opposed to the electric motor EM and mounted on the body frame 41.

[0076] If the inverter 52 is disposed at a position rearward of the electric motor EM, it is easy to dispose the inverter 52 on the rear side of the engine room 43. Thereby, it is easy to access the inverter 52 from the rear of the body. Therefore, from the viewpoint of shortening the working time (improving the working efficiency) in the maintenance work of the inverter 52, it is preferable that, as in the present embodiment, the inverter 52 is disposed on one side in the front-rear direction with respect to the electric motor EM (that is, on the same side as the side on which the first electrical device E1 is disposed with respect to the battery unit BU in the front-rear direction).

[0077] As Figure 6As shown, 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 arranged in sequence from above.

[0078] In this configuration, the free space between the first electrical device E1 and the inverter 52 is effectively used as the configuration space for the third electrical device E3. Even in a structure where the electrical device EP includes the third electrical device E3 in addition to the first electrical device E1 and the inverter 52, it is preferable to efficiently (compactly) arrange the third electrical device E3 in the engine room 43. From this perspective, it is preferable that, as in the present embodiment, the third electrical device E3 is located between the first electrical device E1 and the inverter 52.

[0079] The fourth electrical device E4 (DC-DC converter 55) and the low-voltage battery 56 are arranged at a position to the left of the battery unit BU. The low-voltage battery 56 is arranged at a position below the fourth electrical device E4 and shifted forward relative to the fourth electrical device E4. That is, the fourth electrical device E4 is located above the low-voltage battery 56.

[0080] In this configuration, for example, compared with a structure in which the fourth electrical device E4 and the battery unit BU are arranged side by side in the front-rear direction, it is easier to reduce the body size in the front-rear direction. In addition, as described above, the fourth electrical device E4 is mounted on the engine hood support portion 101 (refer to Figure 4 ), so there is no need to prepare mounting components other than the engine hood support portion 101 (dedicated mounting components for mounting the fourth electrical device E4). Thus, the number of components for mounting the fourth electrical device E4 can be reduced. Therefore, in the case where the electrical device EP includes the fourth electrical device E4, from the viewpoints of a small number of components and easy realization of a structure suitable for a small (small turning type) hydraulic excavator 1, the following structure is preferable. That is, it is preferable that, as in the present embodiment, the fourth electrical device E4 is arranged on one side (the left side in the present embodiment) in the width direction of the body with respect to the battery unit BU and is mounted on the engine hood support portion 101.

[0081] If the fourth electrical device E4 and the low-voltage battery 56 are arranged together to the left of the battery unit BU, it is easy to access the fourth electrical device E4 and the low-voltage battery 56 simultaneously from the left. Thus, when maintaining the fourth electrical device E4 and the low-voltage battery 56 simultaneously, the operation time is shortened. Additionally, if the relatively heavy low-voltage battery 56 in the electrical device EP is arranged at the lowest possible position, the center-of-gravity position of the machine body becomes lower. Therefore, from the viewpoints of improving the operation efficiency of maintenance work and stabilizing the machine body, it is preferable that, as in the present embodiment, the low-voltage battery 56 is arranged on one side of the one side of the battery unit BU, and the fourth electrical device E4 is arranged at a position above the low-voltage battery 56.

[0082] A fan 71 is arranged at a position in front of the fourth electrical device E4 and the low-voltage battery 56. The fan 71 is composed of an electric fan and is driven by low-voltage electric power supplied from the DC-DC converter 55 and the low-voltage battery 56. When the fan 71 is driven, air (outside air) is inhaled (obtained) into the engine room 43. Thereby, a flow of air (wind) is formed in the engine room 43. More specifically, a first opening (not shown) is provided in the exterior portion 4c of the upper rotating body 4 (refer to Figure 1 , for example, the machine body frame 41). In addition, a second opening 43L2 is provided in the left engine hood member 43L included in the exterior portion 4c (refer to Figure 1 ). The above-mentioned air flows into the engine room 43 from the above-mentioned first opening and is discharged from the second opening 43L2.

[0083] As Figure 7 shown, 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. To the left of the first fan 71a, a heat exchanger 64 is arranged at a position opposite to the first fan 71a. The heat exchanger 64 and the fan 71 (the first fan 71a, the second fan 71b) are arranged inside a wind guide portion 72 (also refer to Figure 3 and Figure 4 ). The wind guide portion 72 is composed of a hollow metal member extending in the left-right direction. The entire left side portion of the wind guide portion 72 is open. A part of the right side portion of the wind guide portion 72 is open. The wind guide portion 72 constitutes a flow path of the air flowing in the engine room 43. The wind guide portion 72 is arranged at a position to the left of the battery unit BU and the electric motor EM. In addition, a hydraulic pump 61 is arranged to the right of the electric motor EM.

[0084] Next, the support structure of the battery unit BU will be described based on Figure 9 . Figure 9 is a left view showing the support structure of the battery unit BU. Figure 9In the figure, for the sake of convenience, illustrations of the fourth electrical device E4, the low-voltage battery 56, the left side plate portion 103b of the rear engine hood support portion 103, etc. are omitted.

[0085] A battery support plate 121 is provided in the engine compartment 43. That is, the hydraulic excavator 1 has the battery support plate 121 inside the upper revolving body 4 at 4e. The battery support plate 121 is composed of a plate-shaped member made of metal extending in the horizontal direction. The battery support plate 121 is disposed at a position lower than the first electrical device E1 (charger 51). In addition, the battery support plate 121 is disposed at a position higher than the inverter 52.

[0086] The front side of the battery support plate 121 is supported by the support column portion 104 via a vibration-proof member 122. The vibration-proof member 122 is configured to include an elastic body (such as rubber). The support column portion 104 is connected to the machine body frame 41 as described above (refer to Figure 3 ). The rear side of the battery support plate 121 is supported by the machine body frame 41 via a vibration-proof member 122.

[0087] A battery unit BU is provided on the battery support plate 121. More specifically, the battery unit BU is arranged such that the lower surface BU3 (refer to Figure 6 ) is in contact with the upper surface 121U of the battery support plate 121 (refer to Figure 4 ). 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.

[0088] On the rear side of the battery support plate 121 (especially the upper surface 121U), the third electrical device E3 (junction box 54) is installed via the second mounting bracket 123. More specifically, the second mounting bracket 123 is provided in front of the third electrical device E3. The second mounting bracket 123 is formed by bending the upper and lower end portions of a plate-shaped member made of metal extending in the vertical direction forward. The lower end portion of the second mounting bracket 123 is fixed to the battery support plate 121 by fastening members such as bolts. The battery unit BU is disposed in front of the second mounting bracket 123. The upper end portion of the second mounting bracket 123 is connected to the rear surface BU1d of the battery unit BU (refer to Figure 6 ). The third electrical device E3 is fixed to the rear surface portion of the second mounting bracket 123 by fastening members such as bolts.

[0089] In this structure, the battery support plate 121 is effectively used as a mounting component for the third electrical device E3. Thus, in the installation of the third electrical device E3, there is no need to prepare mounting components other than the battery support plate 121 (a dedicated mounting component for installing the third electrical device E3), and the number of components is reduced. In addition, the battery support plate 121 is located between the first electrical device E1 and the inverter 52 in the vertical direction. Therefore, if the third electrical device E3 is mounted on the battery support plate 121, the third electrical device E3 is located between the first electrical device E1 and the inverter 52. Therefore, from the viewpoints of having a small number of components, reliably arranging the third electrical device E3 between the first electrical device E1 and the inverter 52, and efficiently arranging the third electrical device E3 in the engine room 43, the following structure is preferred. That is, it is preferred that, as in the present embodiment, in the structure of the hydraulic excavator 1 having the battery support plate 121 that supports the battery unit BU from below, the third electrical device E3 is mounted on the battery support plate 121.

[0090] 〔4. Supplementary〕

[0091] In the present embodiment, a structure in which the battery unit BU has a rectangular box-shaped outer shape has been described, but the outer shape of the battery unit BU is not limited to the above outer shape. The battery unit BU may be configured as large as possible, and for example, a part of the outer shape may protrude.

[0092] In the present embodiment, a structure in which the first electrical device E1 (charger 51) faces the rear surface BU1d of the battery unit BU has been described, but the first electrical device E1 may face the 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 also face the front surface BU1c of the battery unit BU. In addition, the first electrical device E1 may also face the left surface BU1a of the battery unit BU. And the first electrical device E1 may also face the right surface BU1b of the battery unit BU.

[0093] Furthermore, the above "facing" is not limited to being completely directly opposite (i.e., directly facing). For example, in the present embodiment, the first electrical device E1 is arranged to be inclined along the above one direction (the direction in which the upper side is inclined forward with respect to the vertical direction). Therefore, the first electrical device E1 is also inclined with respect to the side surface BU1 of the battery unit BU (the rear surface BU1d in the present embodiment) (refer to Figure 6 ). Even in this structure, if the first electrical device E1 faces (opposes) the side surface BU1, (by mounting the first electrical device E1 on the engine hood support portion 101,) the effects of the present embodiment can be obtained.

[0094] In the present embodiment, as an electric working machine, a hydraulic excavator 1 as a construction machine is taken as an example for explanation. However, the electric working machine is not limited to the hydraulic excavator 1, and may also be a construction machine such as a wheel loader. In addition, the electric working machine may also be an agricultural machine such as a combine harvester or a tractor.

[0095] 〔5. Supplementary Note〕

[0096] The hydraulic excavator 1 described in the present embodiment can also be expressed as an electric working machine shown in the following supplementary note.

[0097] The electric working machine of Supplementary Note (1) includes:

[0098] A body frame located at the bottom of the body;

[0099] An engine hood support portion erected on the above-mentioned body frame;

[0100] A battery unit for storing electric power;

[0101] An electric motor driven by the electric power supplied from the above-mentioned battery unit; and

[0102] An electrical device electrically connected to the above-mentioned battery unit,

[0103] The above-mentioned electrical device includes a first electrical equipment, and the first electrical equipment is opposed to the side surface of the above-mentioned battery unit and mounted on the above-mentioned engine hood support portion.

[0104] The electric working machine of Supplementary Note (2) is configured based on the electric working machine described in Supplementary Note (1),

[0105] The above-mentioned first electrical equipment is arranged on one side in the front-rear direction of the body with respect to the above-mentioned battery unit.

[0106] The electric working machine of Supplementary Note (3) is configured based on the electric working machine described in Supplementary Note (2),

[0107] The above-mentioned electrical device includes a second electrical equipment, and the second electrical equipment is arranged on the other side in the front-rear direction with respect to the above-mentioned battery unit and mounted on the above-mentioned engine hood support portion.

[0108] The electric working machine of Supplementary Note (4) is configured based on the electric working machine described in Supplementary Note (2) or (3),

[0109] The above-mentioned electric motor is arranged below the above-mentioned battery unit,

[0110] The above-mentioned electrical device includes an inverter, and the inverter is opposed to the above-mentioned electric motor and mounted on the above-mentioned body frame.

[0111] The electric working machine according to Note (5) is configured based on the electric working machine described in Note (4),

[0112] The above inverter is arranged on the above-mentioned one side in the above front-rear direction with respect to the above electric motor.

[0113] The electric working machine according to Note (6) is configured based on the electric working machine described in Note (5),

[0114] The above electrical device includes a third electrical equipment, and the third electrical equipment is located between the above first electrical equipment and the above inverter.

[0115] The electric working machine according to Note (7) is configured based on the electric working machine described in Note (6),

[0116] It is provided with a battery support plate, and the battery support plate supports the above battery unit from below,

[0117] The above third electrical equipment is installed on the above battery support plate.

[0118] The electric working machine according to Note (8) is configured based on the electric working machine described in any one of Notes (1) to (7),

[0119] The above electrical device includes a fourth electrical equipment, and the fourth electrical equipment is on one side in the width direction of the above body with respect to the above battery unit and is installed on the above engine hood support portion.

[0120] The electric working machine according to Note (9) is configured based on the electric working machine described in Note (8),

[0121] The above electrical device includes a low-voltage battery, and the low-voltage battery outputs a voltage lower than that of the above battery unit,

[0122] The above low-voltage battery is arranged on one side of the above one side with respect to the above battery unit,

[0123] The above fourth electrical equipment is arranged at a position above the above low-voltage battery.

[0124] The embodiments of the present invention have been described above, but the scope of the present invention is not limited thereto, and it can be implemented with expansion or modification without departing from the gist of the invention.

[0125] Industrial applicability

[0126] The present invention can be used, for example, in electric working machines such as construction machinery and agricultural machinery.

Claims

1. An electric working machine, characterized in that, Comprising: A body frame located at the bottom of the body; An engine hood support portion erected on the body frame; A battery unit for storing electric power; An electric motor driven by the electric power supplied from the battery unit; And An electrical device electrically connected to the battery unit, The electrical device includes a first electrical equipment, and the first electrical equipment is opposed to the side surface of the battery unit and mounted on the engine hood support portion.

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

3. The electric working machine according to claim 2, wherein The electrical device includes a second electrical equipment, and the second electrical equipment is arranged on the other side in the front-rear direction with respect to the battery unit and mounted on the engine hood support portion.

4. The electric working machine according to claim 2, wherein The electric motor is arranged below the battery unit, The electrical device includes an inverter, and the inverter is opposed to the electric motor and mounted on the body frame.

5. The electric working machine according to claim 4, wherein The inverter is arranged 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 device includes a third electrical equipment located between the first electrical equipment and the inverter.

7. The electric working machine according to claim 6, wherein There is provided a battery support plate for supporting the battery unit from below, The third electrical equipment is mounted on the battery support plate.

8. The electric working machine according to claim 1, wherein The electrical device includes a fourth electrical equipment, and the fourth electrical equipment is arranged on one side of one side in the width direction of the body with respect to the battery unit and mounted on the engine hood support portion.

9. The electric working machine according to claim 8, wherein The electrical device includes a low-voltage battery for outputting a voltage lower than that of the battery unit, The low-voltage battery is arranged on one side of the one side with respect to the battery unit, The fourth electrical equipment is arranged at a position above the low-voltage battery.

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