Electric construction machinery

Abstract

Increase the strength of the battery support members. [Solution] The electric hydraulic excavator 1 has a vehicle body composed of a lower traveling body 2 and an upper rotating body 4, and a work device 6 provided on the upper rotating body 4. The upper rotating body 4 includes a rotating frame 7 to which the work device 6 is attached to the front, a battery 12 mounted on the rotating frame 7 that supplies power to an electric motor which is the power source, a support member 9 provided on the rotating frame 7 surrounding the battery 12 and supporting an outer cover 20 that covers the battery 12, and a battery support member 8 provided on the rotating frame 7 that supports the middle part of the battery 12 in the vertical direction via a mounting member 13 when the lower end of the battery 12 is separated from the rotating frame 7. A connecting member 18 is provided between the support member 9 and the battery support member 8 to connect the two.

Description

Technical Field

[0001] The present disclosure relates to an electric construction machine such as a hydraulic excavator equipped with an electric motor as a power source.

Background Art

[0002] A hydraulic excavator, which is a representative example of a construction machine, includes a self-propelled lower traveling body, an upper revolving body that is rotatably mounted on the lower traveling body via a slewing device, and a working device provided on the front side of the upper revolving body. In recent years, as a measure to suppress global warming and air pollution, an electric hydraulic excavator using an electric motor as a power source has been put into practical use.

[0003] An electric hydraulic excavator is equipped with a battery. The electric motor is driven by the power from the battery, and the hydraulic pump is driven by the electric motor, whereby hydraulic oil for operation is supplied to the hydraulic actuator. The battery is usually mounted on the upper surface of the vehicle frame that forms the base of the upper revolving body via a mounting member having an elastic body such as rubber (Patent Document 1).

[0004] When the battery generates vibrations such as pitching and rolling during the operation of the electric hydraulic excavator, the upper side of the battery swings in the front-rear direction and the left-right direction. In particular, when performing an excavation operation of earth and sand using the working device or when traveling on a slope, the upper side of the battery swings greatly in the front-rear direction, so that the elastic body constituting the mounting member may be twisted and damaged prematurely.

[0005] On the other hand, a configuration has been proposed in which a battery support member extending in the vertical direction is provided on the rear side of the vehicle frame, and a mounting member is arranged between the battery support member and the vertical intermediate portion of the battery. According to this configuration, since a position close to the center of gravity of the battery can be supported via the mounting member, even if the battery vibrates during the operation of the electric hydraulic excavator, the swing of the battery can be suppressed, and damage to the mounting member can be prevented (Patent Document 2).

Prior Art Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2023-150759 [Patent Document 2] Patent No. 7182748 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, in the electric hydraulic excavator described in Patent Document 2, the load from the battery shaking during operation acts on the battery support member, which extends vertically via the mounting member. Therefore, if the battery capacity is increased to increase the operating time of the electric hydraulic excavator, the mass of the battery increases, which presents a problem as an excessive load is placed on the battery support member.

[0008] The object of the present invention is to provide an electric construction machine that can suppress damage to the battery support member caused by the load when the battery shakes. [Means for solving the problem]

[0009] The present invention comprises a self-propelled vehicle body and a work device provided on the vehicle body, wherein the vehicle body is An electric construction machine comprising: a vehicle frame to which the work device is attached to the front; a battery mounted on the vehicle frame and supplying power to an electric motor that serves as a power source; a support member provided on the vehicle frame surrounding the battery and supporting an outer cover that covers the battery; and a battery support member provided on the vehicle frame and supporting the upper and lower middle portion of the battery via a mounting member, such that the lower end of the battery is spaced apart from the bottom plate of the vehicle frame, wherein a connecting member is provided between the support member and the battery support member to connect the two. [Effects of the Invention]

[0010] According to the present invention, the battery support member is connected to the support member by a connecting member, and the battery support member is reinforced, thereby suppressing damage to the battery support member due to the load when the battery shakes. [Brief explanation of the drawing]

[0011] [Figure 1] This is a left side view showing an electric hydraulic excavator according to an embodiment of the present invention. [Figure 2] This is a perspective view of the swivel frame and support members from the left rear. [Figure 3] This is a plan view of the swivel frame and support members as seen from above. [Figure 4] This is a rear view of the swivel frame and support members, seen from the rear. [Figure 5] This is a perspective view from the left rear of the swivel frame with the support members and battery mounted. [Figure 6] This is a top view of the swing frame with the support members and battery mounted. [Figure 7] This is a perspective view from the left rear of the swivel frame with the support members, battery, and electrical equipment mounted. [Modes for carrying out the invention]

[0012] Hereinafter, an electric construction machine according to an embodiment of the present invention will be described in detail with reference to Figures 1 to 7, using the application of an electric hydraulic excavator as an example. In this embodiment, the travel direction of the electric hydraulic excavator will be described as the front-rear direction, and the direction perpendicular to the travel direction will be described as the left-right direction.

[0013] The electric hydraulic excavator 1, a representative example of electric construction machinery, is equipped with a crawler-type lower vehicle 2 that can move forward and backward, and an upper rotating vehicle 4 that is mounted on the lower vehicle 2 via a slewing device 3 so as to be rotatable. The body of the electric hydraulic excavator 1 is composed of the lower vehicle 2 and the upper rotating vehicle 4. A blade (dozer blade) 5 is mounted on the front of the lower vehicle 2 so as to be rotatable in the vertical direction, and this blade 5 is used for excavation work, etc. A swing-type working device 6 is mounted on the front of the upper rotating vehicle 4, and this working device 6 is used for excavation work of earth and sand, etc.

[0014] The swing-type work device 6 includes a swing post 6A that is pivotably mounted on the front side of the slewing frame 7 (described later) so as to swing in the left-right direction, a boom 6B that is rotatably attached to the swing post 6A, an arm 6C that is rotatably attached to the tip of the boom 6B, and a bucket 6D that is rotatably attached to the tip of the arm 6C so as to swing in the up-down direction. The work device 6 also includes a swing cylinder (not shown) for swinging the swing post 6A, a boom cylinder 6E for rotating the boom 6B, an arm cylinder 6F for rotating the arm 6C, and a bucket cylinder 6G for rotating the bucket 6D.

[0015] The upper rotating body 4 is mounted on the lower traveling body 2 via a rotating device 3 so as to be rotatable, and performs a rotating motion on the lower traveling body 2. The upper rotating body 4 is composed of a rotating frame 7 (described later), a battery support member 8, a support member 9, an electric motor and a hydraulic pump (neither shown), a counterweight 10, a cab 11, and a battery 12.

[0016] The slewing frame 7, which serves as the vehicle body frame, forms the base of the upper slewing body 4. The slewing frame 7 is mounted on the lower traveling body 2 via a slewing device 3, and a work device 6 is attached to the front of the slewing frame 7.

[0017] As shown in FIGS. 2 and 3, the swing frame 7 is composed of a bottom plate 7A, a left vertical plate 7B, a right vertical plate 7C, a left side frame 7E, and a right side frame 7F. The bottom plate 7A is made of a thick steel plate extending in the front-rear direction, and is disposed at the center in the left-right direction and extends in the front-rear direction. The left vertical plate 7B and the right vertical plate 7C are erected on the bottom plate 7A, face each other in the left-right direction, and extend in the front-rear direction. The middle portions of the left vertical plate 7B and the right vertical plate 7C in the front-rear direction are connected to a cross plate 7D extending in the left-right direction. The left side frame 7E is fixed to the tip of a left overhanging beam 7E1 that protrudes leftward from the bottom plate 7A and the left vertical plate 7B, and extends in the front-rear direction. The right side frame 7F is fixed to the tip of a right overhanging beam 7F1 that protrudes rightward from the bottom plate 7A and the right vertical plate 7C, and extends in the front-rear direction.

[0018] The distance between the left vertical plate 7B and the right vertical plate 7C becomes smaller from the rear side to the front side, and cylindrical support cylinders 7G are provided at the front ends of the left vertical plate 7B and the right vertical plate 7C. A swing post 6A of the working device 6 is supported by the support cylinders 7G so as to be swingable (swing) in the left-right direction. A battery support member 8 for supporting the battery 12 is provided on the rear side of the swing frame 7.

[0019] The battery support member 8 is disposed on the rear side of the swing frame 7. The battery support member 8 has a rear plate 8A, a left side plate 8B, and a right side plate 8C, and is formed in a U-shaped frame shape when viewed from above. The rear plate 8A is erected on the rear end side of the bottom plate 7A and extends in the left-right direction. The left side plate 8B extends in the front-rear direction between the left end of the rear plate 8A and the cross plate 7D. The rear end portion of the left side plate 8B is welded to the left end portion of the rear plate 8A, and the front end portion of the left side plate 8B is welded to the cross plate 7D. The right side plate 8C extends in the front-rear direction between the right end of the rear plate 8A and the cross plate 7D. The rear end portion of the right side plate 8C is welded to the right end portion of the rear plate 8A, and the front end portion of the right side plate 8C is welded to the cross plate 7D. The portion from the rear end to the middle portion in the front-rear direction of the right side plate 8C faces the left side plate 8B at a certain interval, and the portion from the middle portion to the front end in the front-rear direction of the right side plate 8C forms a bent portion 8D that bends so that the interval from the left side plate 8B becomes smaller.

[0020] The polygonal area enclosed by the lateral plate 7D of the slewing frame 7 and the battery support member 8 constitutes the battery housing section 7H. The battery 12 is attached to the battery support member 8 via a mounting member 13, which will be described later, and the lower side of the battery 12 is housed in the battery housing section 7H while spaced apart (floating) from the bottom plate 7A of the slewing frame 7.

[0021] A support member-side front bracket 8E, which extends to the left from the right side plate 8C, is fixed to the bent portion 8D of the right side plate 8C. A support member-side rear bracket 8F, which extends to the rear from the rear plate 8A, is fixed to the right end of the rear plate 8A. A support member-side left front bracket 8G, which extends to the left from the left side plate 8B, is fixed to the front of the left side plate 8B, and a support member-side left rear bracket 8H, which extends to the left from the left side plate 8B, is fixed to the rear end of the left side plate 8B. Furthermore, the rear plate 8A is provided with two weight mounting holes 8J, which serve as weight mounting sections, spaced apart in the left-right direction. The two weight mounting holes 8J penetrate the rear plate 8A in the front-rear direction, and the counterweight 10, described later, is attached to the slewing frame 7 using bolts (not shown) inserted through these weight mounting holes 8J.

[0022] The support member 9 is positioned behind the horizontal plate 7D and is erected on the swivel frame 7 so as to surround the battery 12. The support member 9 consists of a left leg portion 9A, a right leg portion 9B, a horizontal beam portion 9C, etc., and supports the rear end of the cab 11 as well as the exterior cover 20, which will be described later.

[0023] The left leg 9A is positioned behind the horizontal plate 7D on the left side frame 7E, and rises upward from the left side frame 7E on the left side of the battery 12. The left leg 9A is formed from an L-shaped bent flat steel member, and its lower end is fixed to the left overhang beam 7E1. The upper end of the left leg 9A is bent to the right (towards the battery 12) and is attached to the crossbeam 9C, which will be described later.

[0024] The right leg section 9B is positioned behind the right side frame 7F and rises upward from the right side frame 7F to the right of the battery 12. The right leg section 9B consists of a front frame section 9B1 and a rear frame section 9B2, which are formed in a frame shape using steel plate material or the like. These front frame section 9B1 and rear frame section 9B2 are joined together in an L-shape when viewed from above by welding or the like. The front frame section 9B1 of the right leg section 9B extends to the right from the right vertical plate 7C, and the rear frame section 9B2 extends rearward from the left end of the front frame section 9B1 along the right side plate 8C of the battery support member 8. The upper end of the front frame section 9B1 is connected to the cross beam section 9C. A radiator (not shown) for cooling electrical equipment such as the charger 16 and inverter 17, which will be described later, is attached to the rear frame section 9B2.

[0025] The crossbeam section 9C connects the upper end of the left leg section 9A and the upper end of the right leg section 9B (front frame section 9B1), and extends horizontally above the battery 12. The crossbeam section 9C is composed of a cab support section 9C1 attached to the upper end of the left leg section 9A, and a connecting section 9C2 connecting the upper end of the right leg section 9B (front frame section 9B1) and the cab support section 9C1. The cab support section 9C1 is formed in the shape of a frame having a strong closed cross-section structure, for example, and extends horizontally. Two mounting holes 9C3 are provided on the upper surface of the cab support section 9C1, spaced apart horizontally, and mounting members (not shown) for supporting the rear end of the cab 11, which will be described later, are attached to the mounting holes 9C3. The connecting section 9C2 is formed in the shape of a flat plate using a steel plate or the like, and extends horizontally. The left end of the connecting portion 9C2 is fixed to the right end of the cab support portion 9C1 using a bolt or the like, and the right end of the connecting portion 9C2 is fixed to the left end of the front frame portion 9B1 that constitutes the right leg portion 9B using a bolt or the like.

[0026] A reinforcing plate 9D is provided between the crossbeam section 9C (cab support section 9C1) and the left side plate 8B of the battery support member 8. The reinforcing plate 9D is formed from a steel plate or the like and is a flat plate extending in the vertical direction. The upper end of the reinforcing plate 9D is fixed to the left end of the cab support section 9C1 using bolts, and the lower end of the reinforcing plate 9D is fixed to the left side plate 8B of the battery support member 8 using bolts, etc. The reinforcing plate 9D reinforces the support member 9 and also functions as a bracket for attaching the AC box 15, which will be described later.

[0027] The counterweight 10 is attached to the rear end of the slewing frame 7 (see Figure 1). The counterweight 10 balances the weight with the work device 6 located in front of the slewing frame 7. The outer surface of the counterweight 10 has an arc shape with the central part in the left-right direction protruding to the rear. This configuration ensures that when the upper slewing body 4 rotates, the outer surface of the counterweight 10 remains within a certain rotation radius.

[0028] The cab 11 is mounted on the front left side of the slewing frame 7. The cab 11 consists of a base floor member 11A and a cab box 11B positioned on the floor member 11A, forming the operator's cabin. The front side of the floor member 11A is attached to the slewing frame 7 via, for example, a tilt support member (not shown), and is capable of tilting in the front-rear direction about a pivot axis extending in the width direction (left-right direction) of the slewing frame 7. The rear side of the floor member 11A is inclined diagonally upward, and the rear end of the floor member 11A is supported by the cab support portion 9C1 of the support member 9. That is, the rear end of the floor member 11A is attached to the cab support portion 9C1 via a vibration-damping mount (not shown) located in the mounting hole 9C3 of the cab support portion 9C1.

[0029] Inside the cab 11, there is a driver's seat 11C where the operator sits, and around the driver's seat 11C are travel levers and pedals and work operation levers (neither of which are shown) for operating the electric hydraulic excavator 1. By operating the travel levers and pedals and work operation levers, the operator can perform travel operations with the lower travel body 2, rotation operations with the upper slewing body 4, excavation work with the work device 6, etc.

[0030] The battery 12 is positioned at the rear end of the slewing frame 7, supported by the battery support member 8. The battery 12 has multiple battery modules (not shown), for example, lithium-ion batteries, and supplies power to electric equipment such as electric motors (not shown). The battery 12 is formed in the shape of a rectangular block having a top surface 12A, a bottom surface (not shown), a front surface 12B, a rear surface 12C, a left side surface 12D, and a right side surface 12E, by housing the multiple battery modules within a housing. The multiple battery modules constituting the battery 12 are densely housed within the housing. As a result, the battery 12 has a large mass, and the center of gravity of the battery 12 is located at the center of the battery 12 in the vertical, front-back, and left-right directions.

[0031] A battery-side front bracket 12F is fixed to the right end of the front surface 12B of the battery 12, and a battery-side rear bracket 12G is fixed to the right end of the rear surface 12C of the battery 12. A battery-side left front bracket 12H is fixed to the front of the left side surface 12D of the battery 12, and a battery-side left rear bracket 12J is fixed to the rear end of the left side surface 12D of the battery 12. These four battery-side front brackets 12F, battery-side rear brackets 12G, battery-side left front bracket 12H, and battery-side left rear bracket 12J are attached to the support member-side front bracket 8E, support member-side rear bracket 8F, support member-side left front bracket 8G, and support member-side left rear bracket 8H provided on the battery support member 8 via mounting members 13 having an elastic material such as rubber.

[0032] These four battery-side front brackets 12F, battery-side rear bracket 12G, battery-side left front bracket 12H, and battery-side left rear bracket 12J are each positioned in the middle of the battery 12 in the vertical direction. As a result, the battery 12 is supported by the battery support member 8 via the four mounting members 13 at a position close to the center of gravity, and the lower end of the battery 12 is housed in the battery housing 7H in a state where it is spaced apart (floating) from the bottom plate 7A of the slewing frame 7. In this way, the battery 12 is supported by the battery support member 8 via the four mounting members 13 at a position close to the center of gravity, which suppresses the upper part of the battery 12 from swaying in the front-rear and left-right directions when the electric hydraulic excavator 1 is in operation.

[0033] A rapid charging inlet 14 is attached to the left overhanging beam 7E1 of the slewing frame 7. The rapid charging inlet 14 connects an external power supply (not shown) for rapid charging to the battery 12. An AC box 15 is attached to the reinforcing plate 9D of the support member 9. The AC box 15 monitors whether AC current is being supplied to the charger 16 from the external power supply and cuts off the supply of AC current if there is an abnormality. Electrical equipment such as the charger 16 and inverter 17 are arranged on the top surface 12A of the battery 12. The charger 16 converts the AC current supplied from the external power supply into DC current and supplies it to the battery 12. The inverter 17 controls the operation of the electric motor (not shown) by controlling the drive voltage supplied from the battery 12 to the electric motor.

[0034] The connecting member 18 is provided between the support member 9 and the battery support member 8 and connects the two. As shown in Fig. 2, the connecting member 18 is formed of a flat steel material bent in an L shape and has a vertical plate 18A extending in the vertical direction and an upper plate 18B bent forward from the upper end of the vertical plate 18A and extending in the front-rear direction. The front end of the upper plate 18B is attached to the upper surface of the cab support portion 9C1 of the cross beam portion 9C constituting the support member 9 using two bolts 18C. The lower end of the vertical plate 18A is attached using two bolts 18D to a position adjacent to a mounting member 13 provided between the support member side rear bracket 8F and the battery side rear bracket 12G of the rear plate 8A of the battery support member 8. Thereby, the swaying of the support member 9 (cross beam portion 9C) in the front-rear direction is suppressed, and the swaying of the rear plate 8A constituting the battery support member 8 in the front-rear direction is suppressed.

[0035] In this case, as shown in Fig. 4, the height dimension A from the bottom plate 7A of the swivel frame 7 to the two weight mounting holes 8J provided in the rear plate 8A of the battery support member 8 is set smaller than the height dimension B from the bottom plate 7A of the swivel frame 7 to the bolts 18D for attaching the lower end of the connecting member 18 (vertical plate 18A) to the rear plate 8A of the battery support member 8 (A < B). Thus, the mounting position of the connecting member 18 with respect to the rear plate 8A of the battery support member 8 (the position of the bolts 18D) is arranged above the two weight mounting holes 8J provided in the rear plate 8A of the battery support member 8. Thereby, a portion of the rear plate 8A of the battery support member 8 that is above the weight mounting holes 8J is configured to be connected to the cross beam portion 9C of the support member 9 via the connecting member 18.

[0036] In this embodiment, since the battery 12, which has a large mass, is supported by the battery support member 8 via the mounting member 13 at a position close to the center of gravity (midway in the vertical direction), even if the battery 12 vibrates when the electric hydraulic excavator 1 is in operation, the shaking of the upper part of the battery 12 can be suppressed. Here, since the electric hydraulic excavator 1 performs excavation work of earth and sand using the work device 6 and travels up slopes, the battery 12 is often subjected to loads in the front-rear direction. As a result, loads in the front-rear direction are repeatedly applied from the battery 12 to the rear plate 8A of the battery support member 8.

[0037] In contrast, the connecting member 18 connects the crossbeam portion 9C (cab support portion 9C1) of the support member 9 and the rear plate 8A of the battery support member 8. As a result, even if a load is applied in the front-rear direction from the battery 12 to the rear plate 8A of the battery support member 8 when the electric hydraulic excavator 1 is in operation, this load can be transmitted to the support member 9 via the connecting member 18. In this way, the load applied from the battery 12 to the rear plate 8A of the battery support member 8 is distributed between the rear plate 8A of the battery support member 8 and the support member 9, thereby preventing the load from concentrating on the battery support member 8.

[0038] In this case, the lower end of the vertical plate 18A constituting the connecting member 18 is attached using two bolts 18D to a position adjacent to the mounting member 13 located between the support member side rear bracket 8F and the battery side rear bracket 12G on the rear plate 8A of the battery support member 8. This configuration prevents the mounting member 13 from deforming (twisting) due to the load applied from the battery 12 to the rear plate 8A of the battery support member 8.

[0039] Furthermore, the mounting position of the connecting member 18 (position of the bolt 18D) to the rear plate 8A of the battery support member 8 is positioned above the two weight mounting holes 8J provided in the rear plate 8A of the battery support member 8. That is, the portion of the rear plate 8A of the battery support member 8 that is above the weight mounting holes 8J is connected to the crossbeam portion 9C of the support member 9 via the connecting member 18. The rear plate 8A of the battery support member 8 is reinforced in the portion below the weight mounting holes 8J compared to the portion above the weight mounting holes 8J by attaching the counterweight 10, which is a strength member, to the weight mounting holes 8J. In contrast, by attaching the lower end of the connecting member 18 to the portion of the rear plate 8A above the weight mounting holes 8J, the portion of the rear plate 8A above the weight mounting holes 8J can be mainly reinforced by the connecting member 18.

[0040] The front connecting member 19 is provided between the support member 9 and the bottom surface 7A of the slewing frame 7, connecting the two. As shown in Figure 3, the front connecting member 19 is formed from a flat steel material bent into a Z shape and has a vertical plate 19A extending in the vertical direction, a lower plate 19B bent forward from the lower end of the vertical plate 19A, and an upper plate 19C bent backward from the upper end of the vertical plate 19A. The front side of the lower plate 19B is attached to the bottom plate 7A of the slewing frame 7 using bolts, etc., and the rear side of the upper plate 19C is attached to the lower surface of the cab support portion 9C1 which constitutes the crossbeam portion 9C of the support member 9 using bolts, etc.

[0041] Here, the connecting member 18 is fixed to the rear plate 8A of the battery support member 8 behind the rear surface 12C of the battery 12, and the front connecting member 19 is fixed to the slewing frame 7 in front of the front surface 12B of the battery 12. As shown in Figure 6, the connecting member 18 and the front connecting member 19 are linearly continuous in the front-rear direction via the cab support portion 9C1 of the support member 9. As a result, the support member 9 is reinforced by the front connecting member 19, and the load in the front-rear direction applied from the battery 12 to the battery support member 8 can be reliably received by the support member 9. Therefore, the load applied from the battery 12 to the rear plate 8A of the battery support member 8 is transmitted to the support member 9 via the connecting member 18, and also from the support member 9 to the slewing frame 7 via the front connecting member 19. As a result, the load due to the shaking of the battery 12 can be distributed among the rear plate 8A of the battery support member 8, the support member 9, and the slewing frame 7, and the concentration of load on the battery support member 8 can be suppressed.

[0042] The exterior cover 20 is positioned on the slewing frame 7 by being supported by the support member 9 (see Figure 1). The exterior cover 20 covers the battery 12, electric motors and other electric equipment (not shown), hydraulic pumps and other hydraulic equipment (not shown), etc., which are mounted on the slewing frame 7.

[0043] The electric hydraulic excavator 1 according to this embodiment has the configuration described above. When performing excavation work using the electric hydraulic excavator 1, the operator boards the cab 11 and operates the electric motor to drive the hydraulic pump. In this state, the operator operates the travel levers and pedals (not shown) inside the cab 11 to move the electric hydraulic excavator 1 to the work site. Furthermore, by operating the work operation levers (not shown), the operator can rotate the upper rotating body 4 and perform excavation work on soil and sand using the work device 6.

[0044] When the electric hydraulic excavator 1 is in operation, the battery 12 generates vibrations such as pitching and rolling. The battery 12 is supported by the battery support member 8 via four mounting members 13 at a position close to its center of gravity. Specifically, the battery side front bracket 12F, battery side rear bracket 12G, battery side left front bracket 12H, and battery side left rear bracket 12J are provided in the middle of the battery 12 in the vertical direction. These four brackets are attached to the support member side front bracket 8E, support member side rear bracket 8F, support member side left front bracket 8G, and support member side left rear bracket 8H, which are provided on the battery support member 8, via mounting members 13. As a result, even if the battery 12 vibrates when the electric hydraulic excavator 1 is in operation, the shaking of the upper part of the battery 12 can be suppressed.

[0045] On the other hand, even when the battery 12 is supported via the mounting member 13 at a position close to the center of gravity, when the electric hydraulic excavator 1 performs excavation work using the work device 6, or when traveling on a slope, the upper part of the battery 12 will swing in the front-to-back direction. In this case, a load in the front-to-back direction from the battery 12 is repeatedly applied to the rear plate 8A of the battery support member 8, which is provided with the support member side rear bracket 8F. As a result, the mounting member 13, which is positioned between the support member side rear bracket 8F and the battery side rear bracket 12G, may deform (twist) and break.

[0046] In contrast, in this embodiment, the crossbeam portion 9C (cab support portion 9C1) of the support member 9 and the rear plate 8A of the battery support member 8 are connected using a connecting member 18. As a result, even if a load is applied in the front-rear direction from the battery 12 to the rear plate 8A of the battery support member 8 when the electric hydraulic excavator 1 is in operation, this load can be transmitted to the support member 9 via the connecting member 18. As a result, the load applied from the battery 12 to the rear plate 8A of the battery support member 8 can be shared between the battery support member 8 and the support member 9, and the concentration of load on the battery support member 8 can be suppressed.

[0047] Furthermore, the lower end of the vertical plate 18A constituting the connecting member 18 is attached using two bolts 18D to a position adjacent to the mounting member 13 located between the support member side rear bracket 8F and the battery side rear bracket 12G on the rear plate 8A of the battery support member 8. This prevents deformation (twisting) of the mounting member 13 caused by the load applied from the battery 12 to the rear plate 8A of the battery support member 8, thereby extending the lifespan of the mounting member 13.

[0048] Furthermore, a front connecting member 19 is provided between the cab support portion 9C1 of the support member 9 and the bottom surface 7A of the slewing frame 7, and the front connecting member 19 and the connecting member 18 are linearly continuous in the front-rear direction via the cab support portion 9C1 of the support member 9. As a result, the support member 9 can be reinforced by the front connecting member 19, and the front-rear load applied from the battery 12 to the battery support member 8 can be reliably received by the support member 9. Consequently, the load applied from the battery 12 to the rear plate 8A of the battery support member 8 can be shared between the battery support member 8 and the support member 9, and the concentration of load on the battery support member 8 can be reliably suppressed.

[0049] Furthermore, the mounting position of the connecting member 18 to the rear plate 8A of the battery support member 8 (the position of the bolt 18D) is positioned above the two weight mounting holes 8J provided in the rear plate 8A. The rear plate 8A of the battery support member 8 is reinforced below the weight mounting holes 8J by attaching the counterweight 10, which is a strength member, to the weight mounting holes 8J. Therefore, by attaching the lower end of the connecting member 18 (vertical plate 18A) to the part of the rear plate 8A above the weight mounting holes 8J using the bolt 18D, the part of the rear plate 8A above the weight mounting holes 8J can be reinforced by the connecting member 18.

[0050] Thus, the electric hydraulic excavator 1 according to this embodiment has a self-propelled body (lower traveling body 2 and upper rotating body 4) and a work device 6 provided on the upper rotating body 4. The upper rotating body 4 includes a rotating frame 7 to which the work device 6 is attached to the front, a battery 12 mounted on the rotating frame 7 and supplying power to an electric motor which is a power source, a support member 9 provided on the rotating frame 7 surrounding the battery 12 and supporting an outer cover 20 that covers the battery 12, and a battery support member 8 provided on the rotating frame 7 that supports the middle part of the battery 12 in the vertical direction via a mounting member 13 when the lower end of the battery 12 is separated from the rotating frame 7. A connecting member 18 is provided between the support member 9 and the battery support member 8 to connect the two.

[0051] With this configuration, even if a load is applied from the battery 12 to the battery support member 8 when the electric hydraulic excavator 1 is in operation, this load can be transmitted to the support member 9 via the connecting member 18. As a result, the load applied from the battery 12 to the battery support member 8 can be shared between the battery support member 8 and the support member 9, preventing the load from concentrating on the battery support member 8.

[0052] In this embodiment, the battery support member 8 includes a rear plate 8A erected on the rear end side of the slewing frame 7, and a left plate 8B and a right plate 8C positioned on both sides of the rear plate 8A in the left-right direction and erected on the slewing frame 7. The support member 9 includes a left leg portion 9A and a right leg portion 9B erected on the slewing frame 7, sandwiching the battery 12 from the left and right directions, and a crossbeam portion 9C connecting the upper ends of the left leg portion 9A and the right leg portion 9B and extending in the left-right direction above the battery 12. The connecting member 18 is attached to the crossbeam portion 9C of the support member 9 and the rear plate 8A of the battery support member 8. With this configuration, when the electric hydraulic excavator 1 is in operation, the load in the front-rear direction applied from the battery 12 to the battery support member 8 can be shared between the battery support member 8 and the support member 9, and the concentration of load on the rear plate 8A of the battery support member 8 can be suppressed.

[0053] In this embodiment, the connecting member 18 connects the crossbeam portion 9C of the support member 9 to the rear plate 8A of the battery support member 8 at a position adjacent to the mounting member 13 provided between the rear plate 8A of the battery support member 8 and the battery 12. With this configuration, deformation (twisting) of the mounting member 13 provided between the rear plate 8A of the battery support member 8 and the battery 12 can be suppressed due to the load applied from the battery 12 to the rear plate 8A.

[0054] In this embodiment, the connecting member 18 is fixed to the battery support member 8 behind the rear surface 12C of the battery 12, and a front connecting member 19 is provided between the swivel frame 7 and the support member 9, fixed to the swivel frame 7 in front of the front surface 12B of the battery 12, connecting the swivel frame 7 and the support member 9. With this configuration, the support member 9 can be reinforced by the front connecting member 19, and the load in the front-rear direction applied from the battery 12 to the battery support member 8 can be reliably received by the support member 9.

[0055] In this embodiment, the rear plate 8A of the battery support member 8 is provided with a weight mounting hole 8J for attaching the counterweight 10, and the mounting position of the connecting member 18 to the rear plate 8A is positioned above the weight mounting hole 8J. With this configuration, by attaching the counterweight 10 to the weight mounting hole 8J of the rear plate 8A, the portion of the rear plate 8A below the weight mounting hole 8J can be reinforced by the counterweight 10, and the portion of the rear plate 8A above the weight mounting hole 8J can be reinforced by the connecting member 18.

[0056] In this embodiment, a weight mounting hole 8J is provided in the rear plate 8A of the battery support member 8, and a counterweight 10 is attached to the rear end of the slewing frame 7 using a bolt inserted through this weight mounting hole 8J. Generally, batteries 12 become more expensive as their capacity increases, so many users prefer a battery 12 with a smaller capacity, even if it means more frequent charging. In this case, a battery 12 with a smaller capacity also has a smaller mass, so in order to ensure weight balance with the work device 6, it is necessary to attach a counterweight 10 to the rear end of the slewing frame 7. However, the present invention is not limited to this, and for example, the mass of the battery 12 may be increased by increasing the capacity of the battery 12 without mounting a counterweight 10, thereby achieving weight balance with the work device 6.

[0057] Furthermore, in this embodiment, a front connecting member 19 is provided between the bottom plate 7A of the swivel frame 7 and the crossbeam portion 9C of the support member 9, connecting the connecting member 18 and the front connecting member 19 in a linear manner in the front-rear direction via the crossbeam portion 9C of the support member 9. However, the present invention is not limited to this, and the front connecting member 19 may be provided at a position offset to the left-right direction relative to the connecting member 18. [Explanation of Symbols]

[0058] 2. Lower running body (vehicle body) 4. Upper rotating body (vehicle body) 6. Working equipment 7. Swivel frame (vehicle frame) 8 Battery support member 8A rear plate 8B Left side plate 8C Right side plate 8J Weight mounting hole (weight mounting section) 9. Support Members 9A Left leg 9B Right leg 9C Cross beam part 10 Counterweights 12 batteries 13 Mounting member 18 Connecting member 19 Front connecting member 20 Exterior Cover

Claims

1. It has a self-propelled vehicle body and a work device installed on the vehicle body, The aforementioned vehicle body is The vehicle frame to which the aforementioned work device is attached on the front side, A battery mounted on the aforementioned vehicle frame supplies power to the electric motor which serves as the power source, A support member is provided on the vehicle frame surrounding the battery and supports the outer cover that covers the battery, An electric construction machine comprising: a battery support member provided on the vehicle frame, which supports the intermediate portion of the battery in the vertical direction via a mounting member, with the lower end of the battery spaced apart from the bottom plate of the vehicle frame; An electric construction machine characterized in that a connecting member is provided between the support member and the battery support member to connect the two.

2. The battery support member comprises a rear plate erected on the rear end side of the vehicle frame, and left and right side plates positioned on both sides of the rear plate in the left-right direction and erected on the vehicle frame. The support member comprises a left leg portion and a right leg portion erected on the vehicle frame, sandwiching the battery from the left and right directions, and a transverse beam portion connecting the upper ends of the left leg portion and the right leg portion and extending in the left-right direction above the battery. The electric construction machine according to claim 1, characterized in that the connecting member is attached to the crossbeam portion of the support member and the rear plate of the battery support member.

3. The electric construction machine according to claim 2, characterized in that the connecting member connects the crossbeam portion of the support member and the rear plate at a position adjacent to the mounting member provided between the rear plate of the battery support member and the battery.

4. The connecting member is fixed to the battery support member behind the rear surface of the battery. The electric construction machine according to claim 1, characterized in that a front connecting member is provided between the vehicle frame and the support member, fixed to the vehicle frame in front of the front of the battery, and connecting the vehicle frame and the support member.

5. The electric construction machine according to claim 2, characterized in that the rear plate of the battery support member is provided with a weight mounting portion for attaching a counterweight, and the mounting position of the connecting member to the rear plate is positioned above the weight mounting portion.

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