EP4621138A1

EP4621138A1 - Electric hydraulic work machine

Info

Publication number: EP4621138A1
Application number: EP23911268.3A
Authority: EP
Inventors: Toshiro Ueta; Toshihiro Sako
Original assignee: Kobelco Construction Machinery Co Ltd
Current assignee: Kobelco Construction Machinery Co Ltd
Priority date: 2022-12-26
Filing date: 2023-08-30
Publication date: 2025-09-24
Also published as: CN120418508A; EP4621138A4; JP2024092508A; WO2024142484A1

Abstract

A slewing frame (16) includes a frame left end (16L), a bottom sheet (160), and a left wall (161) that stands in a front and back direction. A left and right directional dimension of a region between the frame left end (16L) and the left wall (161) is smaller as advancing backward. A battery (50) is arranged on the slewing frame, an electric motor (53) is arranged in a front part of the region, and a hydraulic pump (54) is arranged in a rear part of the region.

Description

Technical Field

The present invention relates to an electric hydraulic working machine.

Background Art

Working machines, such as a hydraulic excavator, which each include a lower travelling body, an upper slewing body having a slewing frame slewably supported by the lower travelling body, and a working device mounted on the upper slewing body are conventionally known.
Such working machine includes a hydraulic pump that discharges hydraulic fluid to move the working device. The hydraulic pump is driven by an engine or an electric motor that is mounted on the working machine. Patent Literatures 1 and 2 disclose a working machine which includes a battery unit provided in a central part of the upper slewing body, an electric motor and a hydraulic pump that are arranged in a side of the battery unit. In the arts, the upper slewing body includes a plurality of vertical plates extending in a front and back direction on a base sheet of the slewing frame. The electric motor and the hydraulic pump are arranged on the base sheet one after the other in the front and back direction in an outer side of a vertical plate.
In such working machine, there is a case that a vertical plate is arranged obliquely to a front and back direction in order to increase the rigidity and the strength of the upper slewing body or from the aspect of layout of devices over the upper slewing body. Further, there is a case where a support plate of the slewing frame has an outer peripheral portion that curves inwardly as advancing backward in order to make the upper slewing body compact. In this case, there arises a problem that the electric motor and the hydraulic pump are hardly arranged within a limited space in the outer side of the vertical plate.

Citation List

Patent Literature

Patent Literature 1: Japanese Unexamined Patent Publication No. 2019-127751
Patent Literature 2: Japanese Unexamined Patent Publication No. 2021-080704

Summary of Invention

An object of the present invention is to provide an electric hydraulic working machine that makes it possible to compactly arrange an electric motor and a hydraulic pump even in a limited space in an end section of a slewing frame.
An electric hydraulic working machine according to the present invention includes a slewing frame that has a center line extending in a front and back direction, a battery unit that is arranged on the slewing frame, an electric motor that is actuated by electric power supplied from the battery unit, and a hydraulic pump that has a width smaller than a width of the electric motor in a left and right direction in a plan view and discharges hydraulic fluid by receiving a driving force from the electric motor. The slewing frame includes a left side end and a right side end, a bottom sheet, and a vertical plate that stands between one of the side ends and the center line in the front and back direction so as to define a side region between the vertical plate and the one side end in the plan view, a left and right directional dimension of a rear part of the side region being smaller than a left and right directional dimension of a front part of the side region, and the electric motor is arranged in the front part of the side region, and the hydraulic pump is arranged in the rear part of the side region.

Brief Description of Drawings

FIG. 1 is a side view showing a hydraulic excavator according to a first embodiment of the present invention.
FIG. 2 is a plan view showing an internal structure of an upper slewing body of the hydraulic excavator.
FIG. 3 is a plan view showing a structure parallel to the structure shown in FIG. 2, but the battery unit and the hydraulic fluid tank being removed.
FIG. 4 is a side view showing the internal structure of the upper slewing body of the hydraulic excavator.
FIG. 5 is a rear view showing the internal structure of the upper slewing body of the hydraulic excavator.
FIG. 6 is a plan view schematically showing an internal structure of an upper slewing body of a hydraulic excavator according to a second embodiment of the present invention.
FIG. 7 is a plan view schematically showing an internal structure of an upper slewing body of a hydraulic excavator according to a third embodiment of the present invention.
FIG. 8 is a plan view schematically showing an internal structure of an upper slewing body of a hydraulic excavator according to a fourth embodiment of the present invention.
FIG. 9 is a plan view schematically showing an internal structure of an upper slewing body of a hydraulic excavator according to a fifth embodiment of the present invention.
FIG. 10 is a plan view schematically showing an internal structure of an upper slewing body of a hydraulic excavator according to a sixth embodiment of the present invention.
FIG. 11 is a plan view schematically showing an internal structure of an upper slewing body of a hydraulic excavator according to a seventh embodiment of the present invention.

Description of Embodiments

Preferred embodiments of the present invention will be described with reference to the drawings.

First Embodiment

FIG. 1 is a side view showing a hydraulic excavator (working machine) 1 according to a first embodiment of the present invention. FIG. 2 is a plan view showing an internal structure of an upper slewing body 12 of the hydraulic excavator 1 according to the embodiment. In FIG. 2, various cover members are not shown. FIG. 3 is a plan view showing a structure parallel to the structure shown in FIG. 2, but a battery unit 50 and a hydraulic fluid tank 51 being removed. FIG. 4 is a side view showing the internal structure of the upper slewing body 12 of the hydraulic excavator 1. FIG. 5 is a rear view showing the internal structure of the upper slewing body 12 of the hydraulic excavator 1. Directions indicated in each figure are based on the upper slewing body 12 of the hydraulic excavator 1.
The hydraulic excavator 1 includes a lower travelling body (lower body) 10 that is travelable on the ground G, an upper slewing body (machine body) 12 mounted on the lower travelling body 10 slewably about a central axis of rotation extending in a vertical direction, and a working device 14 mounted on the upper slewing body 12.
The lower travelling body 10 includes a pair of a right crawler 11R and a left crawler 11L arranged on right and left, respectively. The right crawler 11R and the left crawler 11L are driven to travel the lower travelling body 10 on the ground G.
The upper slewing body 12 includes a slewing frame 16 and a plurality of components mounted thereon. The components include a machine chamber 17, a cab 18 serving as a driving room, and an unillustrated counterweight constituting a rear end section of the upper slewing body 12.
The working device 14 includes a boom 21, an arm 22, and a bucket 24. The boom 21 is tiltably supported at a front end of the slewing frame 16. The arm 22 is connected to a proximal end of the boom 21 swingably in the vertical direction to the boom 21. The bucket 24 is a leading end attachment for works such as excavation, and is mounted on a proximal end of the arm 22 swingably in the vertical direction to the arm 22. The cab 18 is provided in a front end section of the upper slewing body 12 and in a left of the working device 14. The cab 18 may be provided in a right of the working device 14. The slewing frame 16 has a center line CL (FIG. 2) extending in the front and back direction passing a left and right directional center of the slewing frame 16.
The hydraulic excavator 1 further includes a boom cylinder 26, an arm cylinder 27, and a bucket cylinder 28. The boom cylinder 26 extends and retracts to swing the boom 21 in a raising and lowering direction. The arm cylinder 27 extends and retracts to swing the arm 22 in the vertical direction. The bucket cylinder 28 extends and retracts to swing the bucket 24 in the vertical direction to the arm 22. These cylinders use hydraulic cylinders.
The hydraulic excavator 1 further includes a battery unit 50 (FIG. 2), a hydraulic fluid tank 51, a control valve 52, an electric motor 53, a hydraulic pump 54 (FIG. 3), and a solenoid valve unit 55.
The battery unit 50 can be charged with electric power, and output the charged electric power. In this embodiment, the battery unit 50 has a rectangular parallelepiped shape.
The hydraulic fluid tank 51 stores hydraulic fluid therein. The hydraulic fluid tank 51 receives hydraulic fluid flowing out of a hydraulic circuit including the control valve 52, and supplies the hydraulic fluid to the hydraulic pump 54.
The control valve 52 is arranged between the hydraulic pump 54 and a hydraulic actuator (the hydraulic cylinder, the slewing motor) provided in the hydraulic excavator 1, and opens to control a flow passage and a flow rate of the hydraulic fluid to be supplied to each of the actuators.
The electric motor 53 is driven by electric power supplied from the battery unit 50, and has an output shaft (drive shaft) 53S (FIG. 3) for transmitting a driving force to the hydraulic pump 54 by a rotation thereof. An unillustrated inverter may be provided between the battery unit 50 and the electric motor 53.
The hydraulic pump 54 is actuated (rotated) by receiving the driving force from the electric motor 53 to thereby discharge the hydraulic fluid to be supplied to each of the actuators. The hydraulic pump 54 includes a connection portion connected with the output shaft 53S of the electric motor 53, the connection portion receiving the driving force.
The solenoid valve unit 55 (FIG. 3) is provided in a hydraulic circuit for actuating each of the actuators. The solenoid valve unit 55 includes a plurality of valves which receive an instruction signal from an unillustrated control part to execute opening.
The slewing frame 16 has a substantially rectangular shape in the plan view as shown in FIG. 2 and FIG. 3. The slewing frame 16 includes a bottom sheet 160, a swing post 16S, a front wall 16P and a rear wall 16Q (FIG. 4), a left wall (vertical plate) 161, and a right wall 162.
The bottom sheet 160 constitutes a main body of the slewing frame 16, and has a sheet-shape facing upward and downward. The bottom sheet 160 includes a frame front end 16F, a frame rear end 16B, a frame left end (side end) 16L and a frame right end 16R. The frame front end 16F is equivalent to a front end of the bottom sheet 160 and extends in the left and right direction. The frame rear end 16B is equivalent to a rear end of the bottom sheet 160 and extends in the left and right direction. The frame left end 16L is equivalent to a left end (left side end) of the bottom sheet 160 and extends in the front and back direction. The frame right end 16R is equivalent to a right end (right side end) of the bottom sheet 160 and extends in the front and back direction.
The swing post 16S protrudes frontward from a central portion of the frame front end 16F. As shown in FIG. 4, the swing post 16S includes a pair of an upper support and a lower support, and swingably supports the working device 14 shown in FIG. 1.
The front wall 16P (FIG. 4) is a wall portion that stands on the bottom sheet 160 along the frame front end 16F. Similarly, the rear wall 16Q is a wall portion that stands on the bottom sheet 160 along the frame rear end 16B.
The left wall 161 and the right wall 162 (FIG. 3) are wall portions that stand on the bottom sheet 160 and extend from a base end of the swing post 16S backward. The left wall 161 stands between the center line CL and the frame left end 16L in the front and back direction, and the right wall 162 stands between the center line CL and the frame right end 16R in the front and back direction. Standing in the front and back direction means extending at least in the front and back direction. Additionally, as shown in FIG. 3, the left wall 161 and the right wall 162 are arranged in a substantially V-shape in the plan view, the distance between them increasing as advancing backward. Accordingly, the rigidity and strength of the slewing frame 16 can be maintained high by each of the walls including the left wall 161 and the right wall 162.
Further, in this embodiment, while the right wall 162 extends linearly in the plan view, the left wall 161 is in a bent shape. Specifically, the left wall 161 includes, in order from front to back, a first left wall 161A, a second left wall 161B, and a third left wall 161C. The first left wall 161A and the second left wall 161B slant backward and outward in the left and right direction, and a slant angle of the second left wall 161B is larger than a slant angle of the first left wall 161A. The third left wall 161C is connected to a rear end of the second left wall 161B and extends along the front and back direction. Consequently, the first left wall 161A, the second left wall 161B, and the third left wall 161C are getting farther away in the left and right direction from the center line CL in this order.
Further, as shown in FIG. 4, a top end of the first left wall 161A gently slopes downward as advancing backward. A top end of the second left wall 161B is connected to the top end of the first left wall 161A and slopes further downward. The third left wall 161C has a top end connected to the top end of the second left wall 161B, has a substantially constant height, and then gently rises upward. Thus, the top end of the left wall 161 has a shape that is partially indented downward. As shown in FIG. 4, the electric motor 53 and the hydraulic pump 54 are arranged so as to face the indented portion.
With reference to FIG. 3, a region between the left wall 161 and the frame left end 16L on the slewing frame 16 is defined as a side region S. A front part of the side region S is defined as a front region S1, and a rear part of the side region S is defined as a rear region S2. Owing to the slanting configuration of the left wall 161 in the plan view, a left and right directional dimension of the rear region S2 is smaller than a left and right directional dimension of the front region S1.
In this embodiment, the battery unit 50 is arranged on the slewing frame 16 at least in an inner side in the left and right direction than the left wall 161 and so as to overlap the center line CL. Further, as shown in FIG. 5, the battery unit 50 is placed on a supporting structure provided on the bottom sheet 160 and is supported at a position upwardly away from the bottom sheet 160. The supporting structure includes the second left wall 161B, the third left wall 161C, and a rear portion of the right wall 162 shown in FIG. 3. Further, the electric motor 53 may be arranged in such a state that a part protrudes outward from the bottom sheet 160 as shown in FIG. 5. In this case, the outer part of the electric motor 53 is covered by an unillustrated guard (external panel) standing on the bottom sheet 160.
The electric motor 53 is arranged in the front region S1 of the side region S, and the hydraulic pump 54 is arranged in the rear region S2 of the side region S. In other words, the electric motor 53 is arranged in an outer side in the left and right direction than the second left wall 161B, whereas the hydraulic pump 54 is arranged in an outer side in the left and right direction than the third left wall 161C. Further, in this embodiment, the electric motor 53 and the hydraulic pump 54 are arranged one after the other in such a manner that the output shaft 53S of the electric motor 53 extends in the front and back direction.
As shown in FIG. 3 and FIG. 5, in this embodiment, a width (left and right directional width, maximum width) of the hydraulic pump 54 in the left and right direction (width direction) is smaller than a width of the electric motor 53. Therefore, the electric motor 53 and the hydraulic pump 54 can be arranged in the side region S efficiently by taking advantage of a large and small width relationship between the electric motor 53 and the hydraulic pump 54.
With reference to FIG. 2 and FIG. 4, the hydraulic fluid tank 51 described above is arranged on the left (in a side) of the battery unit 50 and above the hydraulic pump 54.
Further, in front of the electric motor 53, the control valve 52 is arranged opposite to the electric motor 53. In other words, the control valve 52 is arranged in an outer side in the left and right direction than the first left wall 161A.
With reference to FIG. 3 and FIG. 5, the electric motor 53 includes an input part 53A and a motor top surface 53T. The input part 53A is connected to an unillustrated cable extended from the battery unit 50 to thereby receive a supply of electric power. The input part 53A faces an inner side of the electric motor 53 in the left and right direction. Since the electric motor 53 faces the indented portion of the left wall 161 as described above, the cable extended from the battery unit 50 can be easily connected to the input part 53A by passing over the indented portion.
The motor top surface 53T of the electric motor 53 is a top surface of the electric motor 53. On the other hand, the battery unit 50 has a unit bottom surface 50S. The unit bottom surface 50S is a bottom surface of the battery unit 50. As shown in FIG. 5, the unit bottom surface 50S of the battery unit 50 is at a position lower than the motor top surface 53T of the electric motor 53 on the slewing frame 16.
As described above, in this embodiment, the left wall 161 slants backward and outward in the left and right direction in order to maintain the high rigidity of the slewing frame 16. In this configuration where the rear region S2 is narrower than the front region S1 in the side region S in the outer side than the left wall 161 in the left and right direction, the electric motor 53 is arranged in the front region S1 and the hydraulic pump 54 is arranged in the rear region S2 by taking advantage of the large and small width relationship in left and right direction between the electric motor 53 and the hydraulic pump 54. The electric motor 53 and the hydraulic pump 54 can be thus arranged compactly even in a limited space in an end section of the slewing frame 16. This makes it possible to reduce the dimension of the slewing frame 16 in the width direction while concurrently preventing the electric motor 53 and the hydraulic pump 54 from coming interfering with the left wall 161. Further, the battery unit 50 is arranged in the central part of the slewing frame 16 in the inner side in the left and right direction than the left wall 161. This arrangement can reduce a risk of water entering the battery unit 50 in a case where the hydraulic excavator 1 leans or the like. Further, "in the inner side in the left and right direction than the left wall 161" means that the battery unit 50 is arranged at least in a region between the left wall 161 and the center line CL that passes a left and right directional center of the slewing frame 16 and extends in the front and back direction. The battery unit 50 may be arranged at least between the left wall 161 and the right wall 162, i.e., between a pair of vertical walls.
Further, since this embodiment eliminates the need to provide below the battery unit 50 a space to accommodate the electric motor 53 and the hydraulic pump 54, a dimension of the battery unit 50 in the vertical direction can be increased so as to secure a capacity of the battery.
Further, in this embodiment, the hydraulic pump 54 is arranged in the rear region S2, whereas the solenoid valve unit 55 is arranged immediately below the battery unit 50 as shown in FIG. 3. This arrangement can shorten the length of a tube connecting the hydraulic pump 54 with the solenoid valve unit 55 compared with a case where the electric motor 53 and the hydraulic pump 54 are placed in the inverted positions to those in FIG. 3. Thus, a pressure loss in the tube can be reduced.
Further, since the electric motor 53 is arranged in the side region S, which is away from a region below the battery unit 50, the unit bottom surface 50S of the battery unit 50 can be arranged at a position lower than the motor top surface 53T of the electric motor 53. Therefore, the capacity of the battery unit 50 can be increased compared with a case where the electric motor 53 is arranged below the battery unit 50. Besides, the capacity may be increased by further arranging another battery unit 50 over the battery unit 50.
Further, in this embodiment, even though the space in front of the electric motor 53 is occupied by the control valve 52, the electric motor 53 and the hydraulic pump 54 can be compactly arranged in the side region S by taking advantage of the large and small width relationship in left and right direction between the electric motor 53 and the hydraulic pump 54.
Further, in this embodiment, the hydraulic fluid tank 51 can be efficiently arranged by utilizing the space that is in the side of the battery unit 50 and above the hydraulic pump 54. Further, since the hydraulic fluid tank 51 is arranged directly above the hydraulic pump 54, a length of a flow path between the hydraulic pump 54 and the hydraulic fluid tank 51 can be shortened. Additionally, the hydraulic piping can be made shorter and simpler while being prevented from becoming long and complicated. This reduces the costs and also simplifies the installation work.

Second Embodiment

FIG. 6 is a plan view schematically showing an internal structure of an upper slewing body 12 of a hydraulic excavator 1 according to a second embodiment of the present invention. In this embodiment, a difference from the first embodiment is mainly described. The same can be applied to subsequent embodiments.
In this embodiment, a slewing frame 16 further includes a middle wall (opposite vertical plate) 170, and includes a left wall 171 and a right wall 172 in place of the left wall 161 and the right wall 162 of the first embodiment described before. The middle wall 170 is a wall portion that stands on the bottom sheet 160 in a substantially middle part in the front and back direction of the slewing frame 16 and extends in the left and right direction.
The left wall 171 includes a first left wall 171A and a second left wall 171B. The right wall 172 includes a first right wall 172A and a second right wall 172B. As shown in FIG. 6, the walls each slant backward and outward in the left and right direction. Owing to a slanting configuration of the second left wall 171B, a left and right directional width of a rear region S2 of a side region S is smaller than a left and right directional width of a front region S1.
In this configuration, an electric motor 53 is arranged in the front region S1 and a hydraulic pump 54 is arranged in the rear region S2. The electric motor 53 and the hydraulic pump 54 can be thus arranged efficiently in the limited side region S.
Further, even in this embodiment where the middle wall 170 faces the electric motor 53 in front of the electric motor 53, the electric motor 53 is arranged in the front region S1 defined by the middle wall 170 and the second left wall 171B, and the hydraulic pump 54 is arranged in the rear region S2 that is relatively smaller. The electric motor 53 and the hydraulic pump 54 can be thus compactly arranged in the side region S. Further, the electric motor 53 is surrounded by the middle wall 170 and the second left wall 171B. This keeps a vibration of the electric motor 53 from being transmitted to a cab 18 (FIG. 1) provided in front of the electric motor 53.

Third Embodiment

FIG. 7 is a plan view schematically showing an internal structure of an upper slewing body 12 of a hydraulic excavator 1 according to a third embodiment of the present invention. In this embodiment, a bottom sheet 160 of a slewing frame 16 has a rear part having a substantially arc shape. On the other hand, a second left wall 171B of a left wall 171 extends in a front and back direction.
In this configuration, a left and right directional width of a rear region S2 of a side region S is smaller than a left and right directional width of a front region S1. However, an electric motor 53 is arranged in the front region S1 and a hydraulic pump 54 is arranged in the rear region S2 by taking advantage of a large and small width relationship in left and right direction between the electric motor 53 and the hydraulic pump 54. The electric motor 53 and the hydraulic pump 54 can be thus arranged compactly even in a limited space in an end section of the slewing frame 16. Similarly, a bottom sheet 160 of a slewing frame 16 in other embodiments may have a rear part having a substantially arc shape.

Fourth Embodiment

FIG. 8 is a plan view schematically showing an internal structure of an upper slewing body 12 of a hydraulic excavator 1 according to a fourth embodiment of the present invention. This embodiment differs from the second embodiment described above in the aspect of a shape of a left wall 171. Specifically, the left wall 171 includes a first left wall 171A, a second left wall 171B, and a third left wall 171C. On the other hand, a right wall 172 includes a first right wall 172A and a second right wall 172B. Further, a middle wall 170 extends in such a manner as to pass between the first left wall 171A and the second left wall 171B and between the first right wall 172A and the second right wall 172B.
The first left wall 171A and the first right wall 172A slant so as to expand their mutual distance as advancing backward. The second left wall 171B has a front end positioned in a slightly inner side than a rear end of the first left wall 171A in the left and right direction. The second left wall 171B slants outward in the left and right direction at an angle steeper than the first left wall 171A. The third left wall 171C connected to the second left wall 171B extends along the front and back direction. Thus, as shown in FIG. 8, the middle wall 170 and the second left wall 171B define a region having a wedge (triangle) shape on the slewing frame 16. The region corresponds to a front region S1 in this embodiment. On the other hand, a left and right directional width of a rear region S2 is smaller than a left and right directional width of the front region S1, but is substantially constant in the front and back direction.
In this embodiment, an electric motor 53 is arranged in the front region S1 and a hydraulic pump 54 is arranged in the rear region S2 described above. The electric motor 53 and the hydraulic pump 54 are arranged one after the other in the front and back direction. Thus, the electric motor 53 and the hydraulic pump 54 can be compactly arranged even in a limited space in an end section of the slewing frame 16 by taking advantage of a large and small width relationship in left and right direction between the electric motor 53 and the hydraulic pump 54.
Further, in this embodiment, the front end of the second left wall 171B is displaced in the inner side in the left and right direction to thereby form the region having the wedge shape. The electric motor 53 is arranged so as to fit in the region. Further, the thus-slanted second left wall 171B provides more area (length) to support the battery unit 50 from below than in a case where a front end of the second left wall 171B is continuously connected from a rear end of the first left wall 171A. This makes it possible to stably support the battery unit 50 and increase the stability of the slewing frame 16. This can further increase the stability of the battery unit 50 in a region that is in periphery of the electric motor 53 and the hydraulic pump 54 and is liable to transmit vibrations to the battery unit 50.

Fifth Embodiment

FIG. 9 is a plan view schematically showing an internal structure of an upper slewing body 12 of a hydraulic excavator 1 according to a fifth embodiment of the present invention. In this embodiment, while a slewing frame 16 includes a left wall 171 and a right wall 172 that are similar to those of the second embodiment, an arrangement pattern of an electric motor 53 and a hydraulic pump 54 is different from that in the second embodiment. Specifically, the electric motor 53 and the hydraulic pump 54 are arranged obliquely to the front and back direction in a side region S so that an output shaft 53S (see FIG. 3) of the electric motor 53 is farther away from a center line CL as advancing backward. In this case, since the electric motor 53 and the hydraulic pump 54 are arranged along a second left wall 171B as shown in FIG. 9, the electric motor 53 and the hydraulic pump 54 are kept from coming into contact with the second left wall 171B. Further, the electric motor 53 and the hydraulic pump 54 can be compactly arranged in a V-shaped region including a front region S1 and a rear region S2 in a plan view by taking advantage of the large and small width relationship in left and right direction between the electric motor 53 and the hydraulic pump 54.
In other words, in this embodiment, a rear portion of the second left wall 171B arranged in an outer side than a front portion of the second left wall 171B in the left and right direction defines a narrower rear region S2 in the side region S. The electric motor 53 is arranged with its output shaft 53S extending obliquely, and accordingly, the hydraulic pump 54 is thus arranged obliquely, thereby enabling a compact arrangement of the electric motor 53 and the hydraulic pump 54 even in a limited space.

Sixth Embodiment

FIG. 10 is a plan view schematically showing an internal structure of an upper slewing body 12 of a hydraulic excavator 1 according to a sixth embodiment of the present invention. This embodiment differs in that a second left wall 171B slants outward in a left and right direction at an angle steeper than in the second embodiment. In this case, as shown in FIG. 10, a right rear end corner 54T of a hydraulic pump 54 overlaps the second left wall 171B in a plan view. Practically, in this embodiment, a top end of the second left wall 171B shown in FIG. 10 is at a position lower than the rear end corner 54T in the same manner as a top end of the third left wall 161C shown in FIG. 4. Consequently, the rear end (the protrusion portion) of the hydraulic pump is kept from coming into contact with the second left wall 171B.
In this embodiment, the positional relationship between the members is described as follows. The hydraulic pump 54 has the rear end corner (protrusion portion) 54T protruding from a side region S toward a center line CL. On the other hand, the second left wall 171B includes a first top end, and a second top end that is at a position lower than the first top end and lies below the rear end corner 54T. In this case, the first top end is in a front portion of the second left wall 171B, and the second top end is in another portion of the second left wall 171B and lies below the rear end corner 54T.
A part of the electric motor 53 may be in the portion that overlaps the second left wall 171B in the plan view and is above the top end of the second left wall 171B. Further, the second left wall 171B may have a constant height smaller than a height of the first left wall 171A. In this case, the top end of the second left wall 171B is the second top end of the present invention, and a top end of the first left wall 171A is the first top end of the present invention.

Seventh Embodiment

FIG. 11 is a plan view schematically showing an internal structure of an upper slewing body 12 of a hydraulic excavator 1 according to a seventh embodiment of the present invention. In this embodiment, while a left wall 171 and a right wall 172 slant in the same manner as in the second embodiment (FIG. 6), a battery unit 50 is arranged in a backward position. Further, a front end of the battery unit 50 is at a further rear position than the electric motor 53. Additionally, a left end of the battery unit 50 is in an outer side than a second left wall 171B and is arranged above a hydraulic pump 54 so as to overlap the hydraulic pump 54. In this embodiment, a portion of the second left wall 171B may be indented downward so as to keep away from the battery unit 50. In this configuration, a space above the hydraulic pump 54 may be used to accommodate a part of the battery unit 50. In FIG. 11, a hydraulic fluid tank 51 described above may be arranged above the hydraulic pump 54 and near to the battery unit 50, or the hydraulic fluid tank 51 may be arranged at another position.
The configuration of this embodiment can produce the same effect as the first embodiment. Further, the arrangement of the battery unit 50 as shown in FIG. 11 makes it possible to secure a space in front of the battery unit 50. The space may be used to accommodate another device.
In this embodiment, further, a bottom surface of the battery unit 50 is arranged at a position lower than a top surface of the electric motor 53 to enable the capacity of the battery unit 50 to be secured. In FIG. 11, in a case where the capacity of the battery unit 50 is relatively small, the bottom surface of the battery unit 50 may be above the top surface of the electric motor 53.
In this embodiment, the battery unit 50 is arranged at a position backward as shown in FIG. 11. Thus, the battery unit 50 can be stably supported in an area where a distance between a left wall 171 and a right wall 172 is greater.
The present invention is not limited to the embodiments described above. The present invention may be a combination of features of the embodiments described above.
Further, in the embodiments, the description is made about a frame left end 16L of a bottom sheet 160 as an exemplary side end of the slewing frame 16. However, the side end of the slewing frame 16 may be that of a member different from the bottom sheet 160. As an example, an inner side surface of an unillustrated guard (external panel) standing on the bottom sheet 160 may be the side end of the present invention. In this case, a side region S described above is defined between the inner side surface of the guard and a left wall (vertical plate) 161 in the plan view.
Further, in the embodiments, the description is made about the configurations where the battery unit 50 is arranged in the inner side in the left and right direction than the left wall 161. However, the battery unit 50 may be arranged in various ways. In FIG. 11, for example, the battery unit 50 may be shifted rightward so that the left end of the battery unit 50 is positioned to a right of the left wall 171, and a right end of the battery unit 50 is near the frame right end 16R.
Further, in FIG. 11, the battery unit 50 may be arranged so as to cover the top of the hydraulic pump 54. In this case, the left end of the battery unit 50 may be near the frame left end 16L, and the right end of the battery unit 50 may be near the center line CL.
Further, as another embodiment, a battery unit 50 may be arranged so as to overlap a T-shaped portion where a middle wall 170 and a second right wall 172B are joined, and in a right of the center line CL. In this case, a length of the battery unit 50 in the front and back direction may be greater than a sum of lengths of an electric motor 53 and a hydraulic pump 54 in the front and back direction.
Further, a small hydraulic excavator is shown as an exemplary hydraulic excavator in FIG. 1. However, a working machine to which the present invention is applied is not limited to this type, but may be a medium or large hydraulic excavator, or a working machine other than the hydraulic excavators.
An electric hydraulic working machine according to the present invention includes a slewing frame that has a center line extending in a front and back direction, a battery unit that is arranged on the slewing frame, an electric motor that is actuated by electric power supplied from the battery unit, and a hydraulic pump that has a width smaller than a width of the electric motor in a left and right direction in a plan view and discharges hydraulic fluid by receiving a driving force from the electric motor. The slewing frame includes a left side end and a right side end, a bottom sheet, and a vertical plate that stands between one of the side ends and the center line in the front and back direction so as to define a side region between the vertical plate and the one side end in the plan view, a left and right directional dimension of a rear part of the side region being smaller than a left and right directional dimension of a front part of the side region, and the electric motor is arranged in the front part of the side region, and the hydraulic pump is arranged in the rear part of the side region.
In the configuration, the rear part is narrower than the front part in the side region in an outer side than the vertical plate in the left and right direction, the electric motor is arranged in the front part of the side region and the hydraulic pump is arranged in the rear part of the side region by taking advantage of the large and small width relationship in left and right direction between the electric motor and the hydraulic pump. The electric motor and the hydraulic pump can be thus arranged compactly even in a limited space in an end section of the slewing frame.
Further, since the configuration eliminates the need to provide below the battery unit a space to accommodate the electric motor and the hydraulic pump, a dimension of the battery unit in the vertical direction can be increased so as to secure a capacity of the battery.
In the configuration, the battery unit may be arranged at least in an inner side in the left and right direction than the vertical plate.
In this configuration, the arrangement of the battery unit in a central part of the slewing frame can reduce the risk of water entering the battery unit in a case where the working machine leans or the like.
In the configuration, it may be appreciated that the electric motor includes a top surface, and the battery unit includes a bottom surface at a position lower than the top surface of the electric motor on the slewing frame.
In this configuration, since the electric motor is arranged in the side region, which is away from a region below the battery unit, a bottom surface of the battery unit can be at a position lower than a top surface of the electric motor. Therefore, the capacity of the battery unit can be increased compared with a case where the electric motor is arranged below the battery unit.
In the configuration, it may be appreciated that at least one of the electric motor and the hydraulic pump includes a protruding portion protruding from the side region to the center line, and the vertical plate includes: a first top end; and a second top end at a position lower than the first top end and below the protruding portion.
This configuration can keep the protruding portion included in at least one of the electric motor and the hydraulic pump from coming into contact with the vertical plate.
In the configuration, it may be appreciated that a rear portion of the vertical plate is apart away greater from the center line in the left and right direction than a front portion of the vertical plate, the electric motor has an output shaft, the hydraulic pump has a connection portion to be connected with the output shaft, and the electric motor and the hydraulic pump are arranged obliquely to the front and back direction in the side region so that the output shaft is farther away from the center line as advancing backward.
In this configuration, the rear portion of the vertical plate arranged in an outer side than the front portion of vertical plate in the left and right direction defines a narrower rear region in the side region. The narrower rear region is obliquely arranged with the output shaft of the electric motor. This enables a compact arrangement of the electric motor and the hydraulic pump even in a limited space.
In the configuration, the electric hydraulic working machine may further include a control valve that is arranged in front of and opposite to the electric motor and receives the hydraulic fluid discharged from the hydraulic pump.
In this configuration, even though the space in front of the electric motor is occupied by the control valve, the electric motor and the hydraulic pump can be compactly arranged in the side region by taking advantage of the large and small width relationship in left and right direction between the electric motor and the hydraulic pump.
In the configuration, the slewing frame may further include an opposite vertical plate that stands in the left and right direction and is in front of and opposite to the electric motor.
In this configuration, even though the space in front of the electric motor is closed by the opposite vertical plate, the electric motor and the hydraulic pump can be compactly arranged in the side region by taking advantage of the large and small width relationship in left and right direction between the electric motor and the hydraulic pump. Further, the arrangement of the opposite vertical plate can increase the rigidity and the strength of the slewing frame.
In the configuration, the electric hydraulic working machine may further include a hydraulic fluid tank that is arranged in a side of the battery unit and above the hydraulic pump and stores hydraulic fluid to be supplied to the hydraulic pump.
In this configuration, the hydraulic fluid tank can be efficiently arranged by utilizing the space that is in the side of the battery unit and above the hydraulic pump. Further, a length of a flow path between the hydraulic pump and the hydraulic fluid tank can be shortened. Additionally, the hydraulic piping can be made shorter and simpler while being prevented from becoming long and complicated. This reduces the costs and also simplifies the installation work.
In the configuration, one of a left end and a right end of the battery unit may overlap the hydraulic pump in the plan view.
In this configuration, a space above the hydraulic pump may be used to accommodate a part of the battery unit.
As described above, the present invention provides an electric hydraulic working machine that makes it possible to compactly arrange an electric motor and a hydraulic pump even in a limited space in an end section of a slewing frame.

Claims

An electric hydraulic working machine, comprising:
a slewing frame that has a center line extending in a front and back direction;

a battery unit that is arranged on the slewing frame;

an electric motor that is actuated by electric power supplied from the battery unit; and

a hydraulic pump that has a width smaller than a width of the electric motor in a left and right direction in a plan view and discharges hydraulic fluid by receiving a driving force from the electric motor, wherein

the slewing frame includes:
a left side end and a right side end;

a bottom sheet; and

a vertical plate that stands between one of the side ends and the center line in the front and back direction so as to define a side region between the vertical plate and the one side end in the plan view, a left and right directional dimension of a rear part of the side region being smaller than a left and right directional dimension of a front part of the side region, and

the electric motor is arranged in the front part of the side region, and the hydraulic pump is arranged in the rear part of the side region.
The electric hydraulic working machine according to claim 1, wherein
the battery unit is arranged at least in an inner side in the left and right direction than the vertical plate.
The electric hydraulic working machine according to claim 1 or 2, wherein
the electric motor includes a top surface, and

the battery unit includes a bottom surface at a position lower than the top surface of the electric motor on the slewing frame.
The electric hydraulic working machine according to any one of claims 1 to 3, wherein
at least one of the electric motor and the hydraulic pump includes a protruding portion protruding from the side region to the center line, and

the vertical plate includes:
a first top end; and

a second top end at a position lower than the first top end and below the protruding portion.
The electric hydraulic working machine according to any one of claims 1 to 4, wherein
a rear portion of the vertical plate is apart away greater from the center line in the left and right direction than a front portion of the vertical plate,

the electric motor has an output shaft,

the hydraulic pump has a connection portion to be connected with the output shaft, and

the electric motor and the hydraulic pump are arranged obliquely to the front and back direction in the side region so that the output shaft is farther away from the center line as advancing backward.
The electric hydraulic working machine according to any one of claims 1 to 5, further comprising:
a control valve that is arranged in front of and opposite to the electric motor and receives the hydraulic fluid discharged from the hydraulic pump.
The electric hydraulic working machine according to any one of claims 1 to 6, wherein
the slewing frame further includes an opposite vertical plate that stands in the left and right direction and is in front of and opposite to the electric motor.
The electric hydraulic working machine according to any one of claims 1 to 7, further comprising:
a hydraulic fluid tank that is arranged in a side of the battery unit and above the hydraulic pump and stores hydraulic fluid to be supplied to the hydraulic pump.
The electric hydraulic working machine according to any one of claims 1 to 8, wherein
one of a left end and a right end of the battery unit overlaps the hydraulic pump in the plan view.