Work machine

Abstract

An electric hydraulic shovel (1) comprises: a self-propellable vehicle body; a strong electric unit (11) supported on the vehicle body via a first vibration-proofing member (13); an electric motor (15) supported on the vehicle body via a second vibration-proofing member (17); a harness (22) that electrically connects the electric motor (15) and an inverter (14) of the strong electric unit (11); and a ferrite core (24) that is disposed on the path of the harness (22) and absorbs electromagnetic waves radiated from the harness (22). The ferrite core (24) is fixed to the strong electric unit (11) among the strong electric unit (11) and the electric motor (15).

Description

Work machine

[0001] The present disclosure relates to a work machine such as an electric hydraulic excavator.

[0002] A hydraulic excavator as a work machine includes a self-propelled lower traveling body, an upper revolving body rotatably mounted on the lower traveling body, 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 powered by an electric motor has been put into practical use. Generally, an electric hydraulic excavator is equipped with a battery, and a hydraulic pump is driven by an electric motor that rotates by the power from the battery, so that hydraulic oil for operation is supplied to a hydraulic actuator.

[0003] An electric hydraulic excavator is equipped with a plurality of electrical devices such as an inverter and a DC / DC converter for controlling the power supplied from the battery to the electric motor. These plurality of electrical devices are electrically connected to each other via a harness (Patent Document 1). It is known that these electrical devices generate electromagnetic noise (electromagnetic waves) when semiconductor elements for power conversion perform switching. When this electromagnetic noise is radiated from the harness, there is a risk of problems occurring in an electric circuit or the like to which the electrical devices are connected.

[0004] On the other hand, a technique of absorbing electromagnetic waves radiated from a harness by attaching an electromagnetic wave absorber such as a ferrite core to the harness is known. Here, since the electromagnetic noise propagating through the harness has wavelength components, there is an attachment position of an electromagnetic wave absorber that has a high effect of absorbing electromagnetic waves with respect to the length direction of the harness. In addition, a ferrite core is easily damaged by an impact, and the characteristics of absorbing electromagnetic noise are deteriorated when it is damaged. Therefore, it is necessary to avoid external impacts and interference with peripheral components. For this reason, in a vehicle powered by an electric motor, a technique of preventing displacement of the electromagnetic wave absorber with respect to the harness, damage of the electromagnetic wave absorber, etc. during operation of a machine equipped with electrical devices by fixing the electromagnetic wave absorber to the harness has been applied (Patent Document 2).

[0005] Japanese Unexamined Patent Application Publication No. 2023 - 150759, Japanese Unexamined Patent Application Publication No. 2021 - 72389

[0006] In Patent Document 1, the harness is attached to a support frame fixed to the upper rotating body. However, when the hydraulic excavator performs excavation work, that is, when the hydraulic excavator is in operation, strong vibrations and shocks are applied to the upper rotating body on which the electrical equipment is mounted. Therefore, if an electromagnetic wave absorber described in Patent Document 2 were attached to the harness mounted on the hydraulic excavator, there is a risk that the electromagnetic wave absorber would be damaged when the hydraulic excavator is in operation due to the strong vibrations and shocks from the upper rotating body acting on the electromagnetic wave absorber via the support frame.

[0007] The objective of the present invention is to provide a work machine that can extend the lifespan of an electromagnetic wave absorber when it is attached to a harness connecting multiple electrical devices.

[0008] The present invention relates to a work machine comprising a self-propelled vehicle body, a first electrical device supported on the vehicle body via a first vibration-damping member, a second electrical device supported on the vehicle body via a second vibration-damping member, a harness electrically connecting the first electrical device and the second electrical device, and an electromagnetic wave absorber disposed along the path of the harness to absorb electromagnetic waves radiated from the harness, wherein the electromagnetic wave absorber is fixed to either the first electrical device or the second electrical device.

[0009] According to the present invention, the electromagnetic wave absorber is placed in a first electrical device supported by a first vibration-damping member, or in a second electrical device supported by a second vibration-damping member. This suppresses vibrations during the operation of the work machine from directly acting on the electromagnetic wave absorber, thereby preventing damage to the electromagnetic wave absorber.

[0010] This is a left side view showing an electric hydraulic excavator according to an embodiment of the present invention. This is a perspective view showing the battery, inverter, electric motor, harness, etc. mounted on the slewing frame. This is a top view of the inverter, electric motor, harness, ferrite core, etc. from above. This is a perspective view showing the arrangement of the harness, ferrite core, etc. This is a front view showing the arrangement of the inverter, electric motor, harness, ferrite core, etc. This is a perspective view showing multiple harnesses and a ferrite core connected to the inverter. This is a top view showing the flow of cooling air in the electric equipment room. This is a perspective view showing a modified arrangement of the harness, ferrite core, etc.

[0011] Hereinafter, embodiments of the work machines according to the present invention will be described in detail, using an electric hydraulic excavator as an example, with reference to the attached drawings. In these embodiments, the direction of travel of the electric hydraulic excavator will be described as the front-rear direction, and the direction perpendicular to the direction of travel will be described as the left-right direction.

[0012] In Figure 1, the electric hydraulic excavator 1 comprises a self-propelled crawler-type lower vehicle 2 and an upper rotating vehicle 3 that is rotatably mounted on the lower vehicle 2. The body of the electric hydraulic excavator 1 is composed of the lower vehicle 2 and the upper rotating vehicle 3. A swing-type working device 4 is provided on the front side of the upper rotating vehicle 3. The electric hydraulic excavator 1 performs excavation work of earth and sand using the working device 4.

[0013] The upper rotating body 3 is mounted on the lower traveling body 2 so as to be rotatable, and performs rotating movements on the lower traveling body 2. The upper rotating body 3 is composed of a rotating frame 5, a counterweight 6, a cab 7, an exterior cover 10, a high-power unit 11, a battery 12, an electric motor 15, and the like.

[0014] The slewing frame 5 forms the base of the upper slewing body 3. The slewing frame 5 is mounted on the lower traveling body 2 via a slewing mechanism, and the working device 4 is attached to the front side of the slewing frame 5.

[0015] As shown in Figure 2, the slewing frame 5 is composed of a base plate 5A, a left vertical plate 5B and a right vertical plate 5C, a left side frame 5D and a right side frame 5E. The base plate 5A is located in the center in the left-right direction and extends in the front-rear direction. The left vertical plate 5B and the right vertical plate 5C are erected on the base plate 5A and extend in the front-rear direction while facing each other in the left-right direction. The left side frame 5D is fixed to the tip of the left overhang beam that extends to the left from the base plate 5A and the left vertical plate 5B and extends in the front-rear direction. The right side frame 5E is fixed to the tip of the right overhang beam that extends to the right from the base plate 5A and the right vertical plate 5C and extends in the front-rear direction.

[0016] The distance between the left vertical plate 5B and the right vertical plate 5C in the left-right direction gradually decreases from the rear to the front. Swing posts 5F are provided on the front ends of the left vertical plate 5B and the right vertical plate 5C to pivotally support the swing-type work device 4. Multiple frame-side brackets 5G (only two are shown in Figure 2) are provided on the rear side of the slewing frame 5. The high-voltage unit 11 is supported on the frame-side brackets 5G via a first vibration-damping member 13, which will be described later.

[0017] The counterweight 6 is attached to the rear end of the slewing frame 5. The counterweight 6 maintains weight balance with the work device 4 located in front of the slewing frame 5. The outer surface of the counterweight 6 has an arc shape with the central part in the left-right direction protruding to the rear, so that when the upper slewing body 3 rotates, the outer surface of the counterweight 6 stays within a certain rotation radius.

[0018] The cab 7 is mounted on the front left side of the slewing frame 5 and forms the operator's cabin. Inside the cab 7 is a driver's seat 7A where the operator sits. Around the driver's seat 7A are travel levers and pedals and work operation levers (not 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, slewing operations with the upper slewing body 3, and excavation operations with the work device 4.

[0019] The partition member 8 is positioned in the middle of the pivot frame 5 in the front-rear direction. The partition member 8 rises vertically upward from the bottom plate 5A of the pivot frame 5 and extends horizontally between the left side frame 5D and the right side frame 5E. The partition member 8 has a left partition plate 8A positioned between the left side frame 5D and the left vertical plate 5B, an intermediate partition plate 8B positioned between the left vertical plate 5B and the right vertical plate 5C, and a right partition plate (not shown) positioned between the right vertical plate 5C and the right side frame 5E. An electrical equipment room 9 for housing the high-voltage unit 11, electric motor 15, etc. is formed on the rear side of the partition member 8.

[0020] The exterior cover 10 is positioned on the slewing frame 5. The exterior cover 10 is composed of a top cover 10A, a left side cover 10B, a rear cover 10C, a right side cover (not shown), and the like. Inside the exterior cover 10 are electrical equipment such as the high-voltage unit 11 and electric motor 15 mounted on the slewing frame 5, and hydraulic equipment such as hydraulic pumps that supply hydraulic fluid to various hydraulic actuators.

[0021] The first electrical device, the high-power unit 11, is positioned adjacent to the front of the counterweight 6 and at the rear end of the slewing frame 5. The high-power unit 11 includes a battery 12 and an inverter 14, etc. The battery 12 is formed in the shape of a rectangular parallelepiped block extending in the left-right direction, consisting of a plurality of battery modules (not shown) made of, for example, lithium-ion batteries, and a housing that accommodates the plurality of battery modules. The battery 12 constitutes the base of the high-power unit 11. Specifically, the battery 12 has a top surface 12A, a front surface 12B, a rear surface 12C, a left side surface 12D, and a right side surface 12E. The battery 12 supplies power to electrical devices such as the electric motor 15 mounted on the electric hydraulic excavator 1. The electric hydraulic excavator 1 is equipped with a water-cooled battery cooling device (not shown). By cooling the battery 12 with this battery cooling device, the battery 12 is kept within a predetermined temperature range.

[0022] The battery 12 is provided with multiple (for example, four) battery-side brackets 12F. Specifically, one battery-side bracket 12F is provided on the front 12B and rear 12C of the battery 12, and two battery-side brackets 12F are provided on the left side 12D. Each of these multiple battery-side brackets 12F faces a frame-side bracket 5G provided on the slewing frame 5 in the vertical direction.

[0023] A first vibration-damping member 13 is positioned between each of the battery-side brackets 12F and frame-side brackets 5G. The first vibration-damping member 13 is made of an elastic material such as rubber. The battery 12, which forms the base of the high-voltage unit 11, is elastically supported by the swivel frame 5 via the first vibration-damping member 13. Therefore, the battery 12 and components such as the inverter 14 attached to the battery 12 constitute the same vibration system as the high-voltage unit 11.

[0024] The inverter 14, which together with the battery 12 constitutes the high-voltage unit 11, is mounted on the upper surface 12A of the battery 12. The inverter 14 is formed in the shape of a rectangular block extending in the left-right direction. The inverter 14 is located at the right rear corner where the rear surface 12C and the right side surface 12E of the battery 12 intersect. The inverter 14 is elastically supported by the first vibration-damping member 13 via the battery 12 to the slewing frame 5. The inverter 14 controls the operation of the electric motor 15 by controlling the drive voltage supplied from the battery 12 to the electric motor 15.

[0025] The front side of the inverter 14 is a harness connection surface 14A to which harnesses 22, 23, etc., described later, are connected. The harness connection surface 14A is provided with a motor connection connector 14B and several other connection connectors 14C. The motor connection connector 14B and the electric motor 15 are electrically connected via three harnesses 22. The several connection connectors 14C are each connected via harnesses 23 to the battery 12, the onboard charger, and the rapid charger for external power supply (none of which are shown).

[0026] The electric motor 15, which is a second electrical device, is located on the right front side of the battery 12. The electric motor 15 is, for example, a three-phase induction motor and drives a hydraulic pump (not shown) by rotating with three-phase AC power supplied from the battery 12. As shown in Figures 2 and 3, the electric motor 15 is fixed on a rectangular base plate 16 located to the right of the right vertical plate 5C that constitutes the slewing frame 5. The base plate 16 is attached to the bottom plate 5A of the slewing frame 5 via a plurality (four) of second vibration-damping members 17. The second vibration-damping members 17 are made of an elastic material such as rubber. The electric motor 15 fixed to the base plate 16 is elastically supported by the slewing frame 5 via the second vibration-damping members 17. Therefore, the base plate 16 and the electric motor 15 and other components attached to the base plate 16 constitute the same vibration system as the electric motor 15.

[0027] The radiator 18, which acts as a heat exchanger, is located in the electrical equipment room 9 adjacent to the right side of the battery 12 (see Figure 7). The radiator 18 cools the cooling water supplied to electrical equipment such as the inverter 14 and charger (not shown). The radiator 18 faces the right side cover (not shown), which constitutes the outer cover 10, in the left-right direction. A cooling fan 19, consisting of an electric fan, is positioned between this right side cover and the radiator 18.

[0028] The rear cover 10C, which constitutes the outer cover 10, is provided with an air intake 20, and the right side cover is provided with an exhaust port 21 (see Figure 7). As a result, when the cooling fan 19 rotates, outside air is introduced into the electrical equipment room 9 from the air intake 20. This outside air becomes a cooling breeze and flows through the electrical equipment room 9 in the direction of arrow F, then passes through the radiator 18 and is discharged to the outside from the exhaust port 21. This cools the cooling water supplied to electrical equipment such as the inverter 14 and charger (not shown).

[0029] Three harnesses 22 electrically connect the inverter 14 and the electric motor 15. One end of each harness 22 is connected to the motor connector 14B of the inverter 14, and the other end of each harness 22 is connected to the electric motor 15. A ferrite core 24, which will be described later, is attached to the path of the harness 22 (in the middle of its length). As shown in Figure 6, one end of each of two harnesses 23 is connected to a plurality of connection connectors 14C provided on the harness connection surface 14A of the inverter 14, and the other ends of these harnesses 23 are connected to the battery 12, the onboard charger, and the rapid charger for external power supply (none of which are shown), respectively.

[0030] The ferrite core 24, acting as an electromagnetic wave absorber, is mounted on the path of the three harnesses 22 (in the middle of their length). The ferrite core 24 is a cylindrical body with a harness insertion hole 24A formed in its center, through which the three harnesses 22 are inserted. In this case, the ferrite core 24 is positioned at a predetermined mounting location that has a high effect in absorbing electromagnetic waves (electromagnetic noise) propagating through the harnesses 22 in the length direction of the harnesses 22. As a result, electromagnetic waves radiated from the harnesses 22 when the electric hydraulic excavator 1 is in operation are absorbed by the ferrite core 24. A case 24B made of resin material or the like is integrally fixed to the outer circumference of the ferrite core 24, and the case 24B is fixed to the upper surface 12A of the battery 12 using fasteners 24C such as bolts.

[0031] Thus, the ferrite core 24 is fixed to the battery 12 of the high-voltage unit 11, which is supported on the slewing frame 5 via the first vibration-damping member 13, and to the electric motor 15, which is supported on the slewing frame 5 via the second vibration-damping member 17, which is one of the vibration systems, the battery 12. Here, as shown in Figures 4 and 5, the ferrite core 24 is fixed in a position where the harness connection surface 14A and the harness insertion hole 24A of the inverter 14 constituting the high-voltage unit 11 do not face each other.

[0032] Specifically, the mounting position of the ferrite core 24 is set such that the direction in which one end of the harness 22 connected to the harness connection surface 14A (motor connection connector 14B) extends (front-to-back direction) is perpendicular to the direction in which the middle portion of the harness 22 inserted through the harness insertion hole 24A extends (left-to-right direction). This makes it possible to minimize the area of ​​the ferrite core 24 facing the harness connection surface 14A compared to the case where the harness connection surface 14A and the harness insertion hole 24A are arranged to face each other. As a result, interference between the harness 23 connected to the connection connector 14C on the harness connection surface 14A and the ferrite core 24 is suppressed, and the workability when connecting and routing multiple harnesses 23 to the connection connector 14C is improved.

[0033] Furthermore, the ferrite core 24 is fixed to a position adjacent to the edge portion 12G of the battery 12 where the right side surface 12E and the top surface 12A, located on the electric motor 15 side, intersect. This allows the harness 22, which extends to the electric motor 15 through the harness insertion hole 24A of the ferrite core 24, to be separated from the edge portion 12G of the battery 12.

[0034] Furthermore, the ferrite core 24 is positioned upstream of the radiator 18 with respect to the flow direction of the cooling air generated in the electrical equipment room 9 by the cooling fan 19 (direction F indicated by arrow in Figure 7). This allows the cooling air to be supplied to the ferrite core 24 before it is heated after passing through the radiator 18.

[0035] The harness fasteners 25 and 26, which serve as harness fixing points, are attached to the upper surface 12A of the battery 12 adjacent to the ferrite core 24. One harness fastener 25 is positioned between the electric motor 15 and the ferrite core 24, and the three harnesses 22 are bundled together and fixed to the upper surface 12A of the battery 12 using fasteners such as bolts (not shown). The other harness fastener 26 is positioned between the inverter 14 and the ferrite core 24, and the three harnesses 22 are bundled together and fixed to the upper surface 12A of the battery 12 using fasteners.

[0036] As described above, in this embodiment, the intermediate portions of the three harnesses 22 in the longitudinal direction are fixed to the battery 12 by two harness fasteners 25 and 26 positioned on either side of the ferrite core 24. This prevents the ferrite core 24 from shifting position relative to the length of the harnesses 22, and allows the ferrite core 24 to be held in a mounting position that has a high electromagnetic wave absorption effect. Furthermore, since the harnesses 22 inserted through the harness insertion holes 24A of the ferrite core 24 are securely fixed by the two harness fasteners 25 and 26, it is possible to prevent the harnesses 22 from contacting and wearing down the inner periphery of the harness insertion holes 24A.

[0037] 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 7 and operates the electric motor 15 to drive the hydraulic pump (not shown). In this state, the operator operates the travel levers and pedals (not shown) inside the cab 7 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 slewing body 3 and perform excavation work of soil and sand using the work device 4.

[0038] When the electric hydraulic excavator 1 is in operation, the inverter 14 controls the operation of the electric motor 15 by controlling the drive voltage supplied to the electric motor 15 from the battery 12. Here, the inverter 14 generates electromagnetic waves when the semiconductor elements for power conversion switch. However, these electromagnetic waves are absorbed by the ferrite core 24 and are not radiated from the harness 22 connecting the inverter 14 and the electric motor 15. This prevents the electromagnetic waves from having an adverse effect on electrical equipment placed around the inverter 14.

[0039] In this case, since the ferrite core 24 is fixed to the battery 12 of the high-voltage unit 11 supported by the slewing frame 5 via the first vibration-damping member 13, vibrations of the slewing frame 5 are prevented from being directly transmitted to the ferrite core 24. As a result, the lifespan of the ferrite core 24 can be extended, and the electromagnetic wave absorption effect of the ferrite core 24 can be maintained over a long period of time.

[0040] Furthermore, the harness 22 to which the ferrite core 24 is attached is fixed to the upper surface 12A of the battery 12 by two harness fasteners 25 and 26 positioned on either side of the ferrite core 24. One of the harness fasteners 25 is positioned between the electric motor 15 and the ferrite core 24. This prevents vibrations from the electric motor 15 during operation from being transmitted to the ferrite core 24 via the harness 22, thereby extending the lifespan of the ferrite core 24.

[0041] Furthermore, since the harness 22 is fixed by two harness fasteners 25 and 26 positioned on either side of the ferrite core 24, displacement of the ferrite core 24 in the longitudinal direction of the harness 22 is suppressed, and the ferrite core 24 can be held in an mounting position that has a high electromagnetic wave absorption effect. In addition, since the harness 22 inserted through the harness insertion hole 24A of the ferrite core 24 is securely fixed by the two harness fasteners 25 and 26, wear of the harness 22 due to contact with the peripheral edge of the harness insertion hole 24A can be suppressed.

[0042] Furthermore, the ferrite core 24 is fixed to a position adjacent to the edge portion 12G of the battery 12 where the right side surface 12E and the top surface 12A, located on the electric motor 15 side, intersect. This allows the harness 22, which extends to the electric motor 15 through the harness insertion hole 24A of the ferrite core 24, to be kept away from the edge portion 12G of the battery 12, thereby preventing the harness 22 from contacting and wearing down the edge portion 12G of the battery 12.

[0043] Further, when the electric hydraulic excavator 1 is in operation, the cooling fan 19 rotates, so that outside air is introduced into the electric equipment compartment 9 from the air intake 20. This outside air becomes cooling air and flows through the electric equipment compartment 9 in the direction of the arrow F in FIG. 7, and then passes through the radiator 18 and is discharged to the outside from the exhaust port 21. As a result, the cooling water supplied to electric equipment such as the inverter 14 and a charger (not shown) is cooled. Here, the ferrite core 24 is disposed on the upstream side of the radiator 18 with respect to the flow direction of the cooling air generated in the electric equipment compartment 9 by the cooling fan 19. As a result, the cooling air before being warmed by passing through the radiator 18 can be supplied to the ferrite core 24, and the ferrite core 24 can be cooled by using the cooling air for cooling the electric equipment, so that the life of the ferrite core 24 can be extended.

[0044] Thus, in the embodiment, the electric hydraulic excavator 1 includes a self - propelled vehicle body, a high - voltage unit 11 supported by the vehicle body via a first vibration isolator 13, an electric motor 15 supported by the vehicle body via a second vibration isolator 17, a harness 22 that electrically connects between the inverter 14 of the high - voltage unit 11 and the electric motor 15, and a ferrite core 24 that is disposed on the path of the harness 22 and absorbs electromagnetic waves radiated from the harness 22. In the electric hydraulic excavator 1, the ferrite core 24 is configured to be fixed to one of the high - voltage unit 11 and the electric motor 15 (the high - voltage unit 11).

[0045] According to this configuration, since the ferrite core 24 is fixed to the battery 12 of the high - voltage unit 11 supported by the swing frame 5 via the first vibration isolator 13, it is possible to prevent the vibration of the swing frame 5 from being directly transmitted to the ferrite core 24. As a result, the life of the ferrite core 24 can be extended, and the effect of absorbing electromagnetic waves by the ferrite core 24 can be maintained over a long period.

[0046] In the embodiment, the harness 22 is fixed to the battery 12 of the high-voltage unit 11 by harness fixtures 25 and 26 disposed with a ferrite core 24 therebetween. According to this configuration, displacement of the ferrite core 24 in the length direction of the harness 22 can be suppressed, and the ferrite core 24 can be held at an attachment position having a high effect of absorbing electromagnetic waves. Further, since the harness 22 inserted into the harness insertion hole 24A of the ferrite core 24 is securely fixed by the two harness fixtures 25 and 26, it is possible to suppress the harness 22 from contacting and wearing against the peripheral portion of the harness insertion hole 24A.

[0047] In the embodiment, the ferrite core 24 has a harness insertion hole 24A through which the harness 22 is inserted, and the ferrite core 24 is fixed in a direction in which the harness connection surface 14A of the inverter 14 of the high-voltage unit 11 to which the harness 22 is connected and the harness insertion hole 24A are orthogonal. According to this configuration, the area of the ferrite core 24 facing the harness connection surface 14A can be made as small as possible compared to the case where the harness connection surface 14A and the harness insertion hole 24A are arranged to face each other. As a result, interference between the harness 23 connected to the connection connector 14C of the harness connection surface 14A and the ferrite core 24 can be prevented, and the workability when connecting and arranging a plurality of harnesses 23 to the connection connector 14C can be improved.

[0048] In the embodiment, the ferrite core 24 is fixed to the battery 12 of the high-voltage unit 11, and a radiator 18 for cooling the high-voltage unit 11 by supplying cooling air generated by a cooling fan 19 is provided on the vehicle body, and the ferrite core 24 is disposed on the upstream side of the radiator 18 with respect to the flow direction of the cooling air by the cooling fan 19. According to this configuration, the life of the ferrite core 24 can be extended by cooling the ferrite core 24 using the cooling air before being heated by passing through the radiator 18.

[0049] In this embodiment, the first electrical device is a high-voltage unit 11 including a battery 12 and an inverter 14 that controls the power of the battery 12, and the second electrical device is an electric motor 15 driven by power supplied from the battery 12 via the inverter 14, and the ferrite core 24 is fixed in a position adjacent to the edge portion 12G of the battery 12 located on the electric motor 15 side. With this configuration, the harness 22 extending to the electric motor 15 through the harness insertion hole 24A of the ferrite core 24 can be kept away from the edge portion 12G of the battery 12, and the harness 22 can be prevented from contacting and wearing down the edge portion 12G of the battery 12.

[0050] In this embodiment, the harness 22 is shown as being fixed to the battery 12 by harness fasteners 25 and 26 arranged with the ferrite core 24 in between. However, the present invention is not limited to this, and may be configured as shown in the modified example in Figure 8, for example.

[0051] In other words, the harness 22 may be fixed to the battery 12 of the high-voltage unit 11, specifically to the battery 12 to which the ferrite core 24 is fixed, by a harness fixing device 25, and the harness fixing device 25 may be positioned between the electric motor 15 and the ferrite core 24. In this configuration as well, the vibrations transmitted to the ferrite core 24 via the harness 22 during operation of the electric motor 15 can be suppressed by the harness fixing device 25, thereby extending the lifespan of the ferrite core 24.

[0052] In this embodiment, the ferrite core 24 and harness fasteners 25 and 26 are fixed to the upper surface 12A of the battery 12 that constitutes the high-voltage unit 11. However, the present invention is not limited to this, and may be fixed to other members that constitute the vibration system of the high-voltage unit 11, such as the inverter 14. Furthermore, the ferrite core 24 and harness fasteners 25 and 26 may be fixed to the vibration system of the electric motor 15, such as the base plate 16 supported by the swivel frame 5 via the second vibration-damping member 17.

[0053] In this embodiment, the harness 22 is fixed to the battery 12 by harness fasteners 25 and 26 arranged with the ferrite core 24 in between. However, the present invention is not limited to this, and the harness 22 may be fixed using, for example, three or more harness fasteners.

[0054] Furthermore, the embodiment illustrates an electric hydraulic excavator 1 equipped with an electric motor 15 as a power source. However, the present invention is not limited to this and can be broadly applied to all types of work machines equipped with electric devices other than electric motors, such as hydraulic excavators equipped with engines as a power source.

[0055] 1. Electric hydraulic excavator (construction machine) 2. Lower traveling body (vehicle body) 3. Upper rotating body (vehicle body) 11. High-voltage unit (first electrical equipment) 12. Battery 12G edge section 13. First vibration-damping member 14. Inverter 14A harness connection surface 15. Electric motor (second electrical equipment) 17. Second vibration-damping member 18. Radiator (heat exchanger) 19. Cooling fan 22, 23. Harness 24. Ferrite core (electromagnetic wave absorber) 25, 26. Harness fixing device (harness fixing part)

Claims

1. A work machine comprising a self-propelled vehicle body, a first electrical device supported on the vehicle body via a first vibration-damping member, a second electrical device supported on the vehicle body via a second vibration-damping member, a harness electrically connecting the first electrical device and the second electrical device, and an electromagnetic wave absorber positioned along the path of the harness to absorb electromagnetic waves radiated from the harness, wherein the electromagnetic wave absorber is fixed to either the first electrical device or the second electrical device.

2. The work machine according to claim 1, characterized in that the harness is fixed by a harness fixing portion to one of the first electrical equipment and the second electrical equipment to which the electromagnetic wave absorber is fixed, and the harness fixing portion is positioned between the other electrical equipment and the electromagnetic wave absorber.

3. The work machine according to claim 2, characterized in that the harness is fixed to one of the electrical devices by at least two harness fixing parts arranged on either side of the electromagnetic wave absorber.

4. The work machine according to claim 1, wherein the electromagnetic wave absorber has a harness insertion hole through which the harness is inserted, and the electromagnetic wave absorber is fixed in such a way that the harness connection surface of the first electrical equipment to which the harness is connected and the harness insertion hole are perpendicular to each other.

5. The work machine according to claim 1, wherein the electromagnetic wave absorber is fixed to the first electrical equipment, the vehicle body is provided with a heat exchanger that cools the first electrical equipment by supplying cooling air generated by a cooling fan, and the electromagnetic wave absorber is positioned upstream of the heat exchanger with respect to the flow direction of the cooling air from the cooling fan.

6. The work machine according to claim 1, wherein the first electrical equipment is a high-voltage unit including a battery and an inverter for controlling the power of the battery, the second electrical equipment is an electric motor driven by power supplied from the battery via the inverter, and the electromagnetic wave absorber is fixed at a position adjacent to the edge of the battery located on the electric motor side.

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