JP2024004141A - Electrically-driven work machine - Google Patents

Abstract

To provide an electrically-driven work machine which can efficiently separate winds having temperature differences for re-use while achieving a compact layout easily.SOLUTION: A hydraulic shovel serving as an electrically-driven work machine includes: a battery unit; an electric motor which is driven by electric power supplied from the battery unit; a first heat exchanger which cools a refrigerant passing through the battery unit; a hydraulic pump which is driven by the electric motor and discharges a working fluid; a second heat exchanger which cools the working fluid; a fan having a rotation axis; and a partition plate. The first heat exchanger and the second heat exchanger are located overlapping with the fan when viewed from a direction of the rotation axis and located offset from each other in one direction intersecting with the rotation axis. The partition plate is located between the first and second heat exchangers and the battery unit when viewed from above and located crossing in the one direction.SELECTED DRAWING: Figure 4

Description

TECHNICAL FIELD The present invention relates to electric working machines.

Conventionally, various electric working machines including electric motors, such as electric hydraulic excavators, have been proposed. For example, Patent Document 1 discloses an electric hydraulic excavator that separately includes a fan for cooling a radiator, an electric motor, an inverter, etc., and a fan for cooling an oil cooler.

JP2021-155991A

In a configuration in which two fans are provided for cooling a heat exchanger (radiator, oil cooler) as in Patent Document 1, it is necessary to secure space for arranging the two fans within the machine. In this case, especially in a small electric working machine with a small equipment layout space, there is a risk that the arrangement space for other components such as a battery unit will be compressed, making it difficult to stack battery units of sufficient capacity. Therefore, in a small electric working machine, it is desirable to realize a compact layout including the fan.

Further, a temperature difference occurs between the air that is blown to the radiator to cool the radiator and the air that is blown to the oil cooler to cool the oil cooler. This is because the temperature of the hydraulic oil used to drive the hydraulic actuator and returned to the oil cooler is higher than the temperature of the refrigerant flowing through the radiator. For this reason, when the air that cools the radiator and the air that cools the oil cooler are mixed, the temperature of the mixed air will be higher than the air that cools the radiator, so it is difficult to air-cool the equipment. It is no longer suitable for reuse. Therefore, for the above-mentioned reuse, it is desirable to efficiently separate winds with different temperatures.

The present invention was made in order to solve the above problems, and its purpose is to create an electric motor vehicle that can efficiently separate wind with different temperatures for reuse while realizing a compact layout. Our goal is to provide type working machines.

An electric working machine according to one aspect of the present invention includes: a battery unit; an electric motor driven by electric power supplied from the battery unit; a first heat exchanger that cools a refrigerant passing through the battery unit; A hydraulic pump driven by an electric motor to discharge hydraulic oil, a second heat exchanger that cools the hydraulic oil, a fan having a rotating shaft, and a partition plate, the first heat exchanger and the The second heat exchanger is positioned overlapping the fan when viewed from the direction of the rotation axis, and is positioned offset from each other in one direction intersecting the rotation axis,
The partition plate is located between the first heat exchanger, the second heat exchanger, and the battery unit when viewed from above, and is located across the one direction.

According to the above configuration, while easily realizing a compact layout, it is possible to efficiently separate wind having different temperatures for reuse.

1 is a side view showing a schematic configuration of a hydraulic excavator, which is an example of an electric working machine according to an embodiment of the present invention. FIG. 2 is a block diagram schematically showing the configuration of an electrical system and a hydraulic system of the hydraulic excavator. FIG. 2 is a perspective view showing the entire configuration inside the engine room of the hydraulic excavator. FIG. 3 is a plan view showing the overall configuration inside the engine room. 5 is a perspective view of section A in FIG. 4. FIG. FIG. 6 is a perspective view of section A in FIG. 5 with illustration of the fan and the housing omitted. FIG. 5 is a side view of section A in FIG. 4 when viewed from the right side. FIG. 7 is a perspective view of section A from FIG. 6 with illustration of the radiator and oil cooler omitted. FIG. 3 is a perspective view of a wind guide section included in the hydraulic excavator, viewed from above. It is a perspective view when the above-mentioned wind guide section is seen from below. It is a perspective view when the said wind guide part is cut in a horizontal cross section. It is a perspective view when the above-mentioned wind guide part is seen from below in a state where an electric motor is housed. FIG. 3 is a cross-sectional view of the first flow path portion of the wind guiding portion taken along a cross section passing through the electrical equipment. It is a perspective view showing the structure of the modification of the above-mentioned hydraulic excavator.

Embodiments of the present invention will be described below based on the drawings.

[1. Electric work machine〕
FIG. 1 is a side view showing a schematic configuration of a hydraulic excavator (electric shovel) 1, which is an example of an electric working machine according to the present embodiment. The hydraulic excavator 1 includes a lower traveling body 2, a working machine 3, and an upper revolving body 4.

Here, the direction is defined as follows. The direction in which the operator (operator, driver) seated on the driver's seat 41a of the revolving superstructure 4 faces forward is defined as the front, and the opposite direction is defined as the rear. Therefore, when the upper rotating body 4 is not rotating with respect to the lower traveling body 2 (swing angle 0°), the longitudinal direction of the upper rotating body 4 coincides with the direction in which the lower traveling body 2 moves forward and backward. Further, the left side as viewed from the operator seated in the driver's seat 41a is referred to as "left", and the right side is referred to as "right". Further, the direction of gravity perpendicular to the front-rear direction and the left-right direction is defined as the up-down direction, the upstream side of the gravity direction is defined as "upper", and the downstream side is defined as "lower". In the drawing, the hydraulic excavator 1 is shown in a state where the upper rotating body 4 is not rotating with respect to the lower traveling body 2. In addition, in the drawings, the symbols "F" for front, "B" for rear, "R" for right, "L" for left, "U" for upper, and "D" for lower are used as necessary. show.

The lower traveling body 2 includes a pair of left and right crawlers 21 and a pair of left and right travel motors 22. Each travel motor 22 is a hydraulic motor. The left and right travel motors 22 drive the left and right crawlers 21, respectively, so that the hydraulic excavator 1 can be moved forward and backward. The lower traveling body 2 is provided with a blade 23 for leveling the ground and a blade cylinder 23a. The blade cylinder 23a is a hydraulic cylinder that rotates the blade 23 in the vertical direction.

The work machine 3 includes a boom 31, an arm 32, and a bucket 33. By independently driving the boom 31, arm 32, and bucket 33, excavation work such as earth and sand can be performed.

The boom 31 is rotated by a boom cylinder 31a. The boom cylinder 31a has a base end supported by the front part of the upper revolving structure 4, and is movable telescopically. Arm 32 is rotated by arm cylinder 32a. The arm cylinder 32a has a base end supported by the distal end of the boom 31, and is movable telescopically. The bucket 33 is rotated by a bucket cylinder 33a. The bucket cylinder 33a has a proximal end supported by the distal end of the arm 32, and is movable telescopically. The boom cylinder 31a, the arm cylinder 32a, and the bucket cylinder 33a are constituted by hydraulic cylinders.

The upper revolving body 4 is located above the lower traveling body 2 and is provided so as to be rotatable relative to the lower traveling body 2 via a swing bearing (not shown). The upper revolving body 4 includes a control section 41, a revolving frame 42 (airframe frame), a revolving motor 43, an engine room 44, and the like. The upper revolving body 4 is driven by a swing motor 43, which is a hydraulic motor, to swing via a swing bearing.

A hydraulic pump 71 (see FIG. 2) is arranged in the upper revolving body 4. The hydraulic pump 71 is driven by an electric motor 61 (see FIG. 2) inside the engine room 44. The hydraulic pump 71 supplies hydraulic oil (pressure oil) to hydraulic motors (for example, left and right travel motors 22, swing motor 43) and hydraulic cylinders (for example, blade cylinder 23a, boom cylinder 31a, arm cylinder 32a, bucket cylinder 33a). do. A hydraulic motor and a hydraulic cylinder that are driven by being supplied with hydraulic oil from the hydraulic pump 71 are collectively referred to as a hydraulic actuator 73 (see FIG. 2).

A driver's seat 41a is arranged in the control section 41. Various levers 41b are arranged around the driver's seat 41a. The hydraulic actuator 73 is driven by the operator sitting on the driver's seat 41a and operating the lever 41b. As a result, the lower traveling body 2 can travel, the blade 23 can level the ground, the working machine 3 can perform excavation work, the upper revolving body 4 can rotate, and the like.

A battery unit 53 is arranged in the upper revolving body 4 . That is, the hydraulic excavator 1 includes a battery unit 53. The battery unit 53 is composed of, for example, a lithium ion battery unit, and stores electric power for driving the electric motor 61. The battery unit 53 may be configured by unitizing a plurality of batteries, or may be configured by a single battery cell. Further, the upper revolving structure 4 is provided with a power feeding port (not shown). The above-mentioned power feeding port and a commercial power source 51 which is an external power source are connected via a power feeding cable 52. Thereby, the battery unit 53 can be charged.

The upper revolving body 4 is further provided with a lead battery 54 . The lead battery 54 outputs a low voltage (for example, 12V) DC voltage. The output from the lead battery 54 is supplied as a control voltage to, for example, the system controller 67 (see FIG. 2), the drive unit of the fan 91 (see FIG. 5), and the like.

The hydraulic excavator 1 may have a configuration in which a hydraulic device such as the hydraulic actuator 73 and an actuator driven by electric power are used together. Examples of actuators driven by electric power include electric travel motors, electric cylinders, and electric swing motors.

[2. Electrical and hydraulic system configuration]
FIG. 2 is a block diagram schematically showing the configuration of the electrical system and hydraulic system of the hydraulic excavator 1. The hydraulic excavator 1 includes an electric motor 61, a charger 62, an inverter 63, a PDU (Power Drive Unit) 64, a junction box 65, a DC-DC converter 66, and a system controller 67. The system controller 67 is composed of an electronic control unit also called an ECU (Electronic Control Unit), and electrically controls each part of the hydraulic excavator 1 .

The electric motor 61 is driven by electric power supplied from the battery unit 53 via the junction box 65 and the inverter 63. The electric motor 61 is composed of a permanent magnet motor or an induction motor. Electric motor 61 is arranged on swing frame 42 .

The charger 62 (also called a power supply device) converts an AC voltage supplied from the commercial power supply 51 shown in FIG. 1 via the power supply cable 52 into a DC voltage. Inverter 63 converts the DC voltage supplied from battery unit 53 into AC voltage and supplies it to electric motor 61 . This causes the electric motor 61 to rotate. Supply of AC voltage (current) from the inverter 63 to the electric motor 61 is performed based on a rotation command output from the system controller 67.

The PDU 64 is a battery control unit that controls the input/output of the battery unit 53 by controlling an internal battery relay. The junction box 65 includes a charger relay, an inverter relay, a fuse, and the like. The voltage output from the charger 62 described above is supplied to the battery unit 53 via the junction box 65 and PDU 64. Further, the voltage output from the battery unit 53 is supplied to the inverter 63 via the PDU 64 and the junction box 65.

The DC-DC converter 66 steps down the high voltage (eg, 300V) DC voltage supplied from the battery unit 53 via the junction box 65 to a low voltage (eg, 12V). The voltage output from the DC-DC converter 66, like the output from the lead battery 54, is supplied to the system controller 67, the drive section of the fan 91, and the like.

Both the DC-DC converter 66 and the inverter 63 are electrical components EQ that convert the voltage supplied from the battery unit 53 into a desired voltage. That is, the hydraulic excavator 1 includes an electrical component EQ to which power is supplied from the battery unit 53.

A plurality of hydraulic pumps 71 are connected to a rotating shaft (output shaft) of the electric motor 61. The plurality of hydraulic pumps 71 include variable displacement pumps and fixed displacement pumps. In FIG. 2, only one hydraulic pump 71 is illustrated as an example. Each hydraulic pump 71 is connected to a hydraulic oil tank 74 that accommodates (reserves) hydraulic oil. When the hydraulic pump 71 is driven by the electric motor 61 , hydraulic oil in the hydraulic oil tank 74 is supplied to the hydraulic actuator 73 via the hydraulic pump 71 and the control valve 72 . Thereby, the hydraulic actuator 73 is driven. The control valve 72 is a direction switching valve that controls the flow direction and flow rate of hydraulic oil supplied to the hydraulic actuator 73. In this way, the hydraulic excavator 1 includes the hydraulic pump 71 that is driven by the electric motor 61 and discharges hydraulic oil.

[3. Composition inside the engine room]
FIG. 3 is a rear perspective view showing the entire configuration inside the engine room 44 of the hydraulic excavator 1. As shown in FIG. FIG. 4 is a plan view showing the entire configuration inside the engine room 44. As shown in FIG. As shown in FIG. 3, in this embodiment, four battery units 53 are arranged side by side in the front-rear direction on the swing frame 42. As shown in FIG. Each battery unit 53 is located along the left-right direction. The four battery units 53 are arranged on the rotating frame 42 to the left of the rear center.

In this embodiment, the two rear battery units 53 are shifted to the right side, that is, toward the center of the swing frame 42, with respect to the two front battery units 53. Further, of the two rear battery units 53, the rearmost battery unit 53 is located further to the right than the battery unit 53 located in front of it. As a result, the plurality of battery units 53 are efficiently arranged in a limited narrow space near the rear end edge of the rotating frame 42, which is formed in a semicircular shape in plan view (see FIG. 4). Note that the number and arrangement of battery units 53 are not limited to the example of this embodiment.

The plurality of battery units 53 are integrally supported on the rotating frame 42. More specifically, the plurality of battery units 53 are vertically sandwiched between an upper plate 81 and a lower plate 82 (see FIG. 3). The upper plate 81 and the lower plate 82 are connected at a plurality of locations by connecting members 83 that extend in the vertical direction. The connection between the upper plate 81 and the connection member 83 and the connection between the lower plate 82 and the connection member 83 are performed, for example, by bolt fastening. The lower plate 82 is supported on the rotating frame 42 by a support portion 84 in a vibration-proof manner. Note that the installation position of the support portion 84 is not limited to the positions shown in FIGS. 3 and 4, and can be changed as appropriate.

A seat mount 85, which serves as the base of the driver's seat 41a, is located between the upper plate 81 and the driver's seat 41a (see FIG. 1). Note that in FIGS. 3 and 4, only a portion of the seat mount 85 is illustrated for convenience.

On the swing frame 42, on the right side of the battery unit 53, the above-mentioned electric motor 61 (see FIG. 2), hydraulic pump 71, etc. are arranged. The details will be explained below.

FIG. 5 is a perspective view of section A in FIG. 4. Note that the section A in FIG. 4 here refers to a section located on the right side of the battery unit 53 located furthest forward in the engine room 44. As shown in the figure, the hydraulic excavator 1 includes a fan 91. Fan 91 is rotatably supported by housing 90. The housing 90 has a frame shape and is open on the left and right sides. The rotation axis CA of the fan 91 is located along the left-right direction. That is, the fan 91 has a rotation axis CA that extends toward the battery unit 53 (see FIG. 4) when viewed from above. The above-mentioned hydraulic pump 71 is located below the fan 91 (casing 90). The hydraulic pump 71 is connected to a hydraulic oil tank 74 (see FIG. 2) via a hydraulic hose H.

A wind guide section 100 is arranged on the left side of the housing 90, that is, between the housing 90 and the battery unit 53. Note that details of the wind guide section 100 will be described later. As shown in FIGS. 3 and 5, electrical components EQ such as the above-mentioned inverter 63 and DC-DC converter 66 are attached to the wind guide section 100 (particularly the first flow path section 110, which will be described later).

In FIG. 5, the above-mentioned charger 62 is arranged on the rear side of the fan 91 (casing 90) and the hydraulic pump 71. Charger 62 is supported by rotating frame 42 via attachment stay 62a and the like.

FIG. 6 is a perspective view of part A in FIG. 5 with illustration of the fan 91 and the housing 90 omitted. The hydraulic excavator 1 further includes a radiator 92 and an oil cooler 93. The radiator 92 is a first heat exchanger connected to the battery unit 53 shown in FIG. 3 etc. via piping, and cools the refrigerant passing through the battery unit 53. By cooling the refrigerant through heat exchange in the radiator 92 and supplying the refrigerant to the battery unit 53 from the radiator 92, the battery unit 53 can be cooled (water-cooled). The above refrigerant is, for example, cooling water.

The oil cooler 93 is a second heat exchanger connected to a circulating oil path via a hydraulic pump 71, a hydraulic actuator 73 (see FIG. 2), and the like. The oil cooler 93 cools the hydraulic oil flowing through the oil passage by driving the hydraulic pump 71 by heat exchange. Oil cooler 93 is located on the left side (battery unit 53 side) with respect to radiator 92. Note that the oil cooler 93 may be located at the same position as the radiator 92 in the left-right direction. That is, the oil cooler 93 may be located side by side with the radiator 92 in the front-rear direction.

FIG. 7 is a side view of section A in FIG. 4 viewed from the right side, that is, from the direction of the rotation axis CA of the fan 91. The radiator 92 and the oil cooler 93 are positioned overlapping the fan 91 when viewed from the direction of the rotation axis CA of the fan 91. That is, the radiator 92 and the oil cooler 93 are arranged facing the fan 91. Further, as shown in FIGS. 6 and 7, the radiator 92 and the oil cooler 93 are positioned offset from each other in one direction (for example, the front-back direction) intersecting the rotation axis CA. Note that the radiator 92 and the oil cooler 93 may be positioned vertically shifted.

The radiator 92 and the oil cooler 93 are supported inside the casing 90 of FIG. 5 via a stay or the like. Radiator 92 and oil cooler 93 are located between fan 91 and wind guide section 100. Therefore, the fan 91 is located on the opposite side of the air guide section 100 with respect to the radiator 92 and the oil cooler 93.

Note that the electric motor 61 described above is supported by the bottom plate 86 while being connected to the hydraulic pump 71 in the direction in which the output shaft 61a (see FIG. 12) extends (left-right direction). The bottom plate 86 is supported on the swing frame 42 (see FIG. 3, etc.) via a vibration isolating member 87. Thereby, the electric motor 61 and the hydraulic pump 71 are supported on the swing frame 42 in a vibration-proof manner.

FIG. 8 is a perspective view of section A from FIG. 6 with illustration of the radiator 92 and oil cooler 93 omitted. The hydraulic excavator 1 includes a wind guide section 100. The wind guide section 100 includes a first flow path section 110 and a second flow path section 120. Wind generated by driving the fan 91 passes through the first flow path section 110 and the second flow path section 120. The details of the wind guiding section 100 will be explained below.

FIG. 9 is a perspective view of the wind guide section 100 viewed from above. FIG. 10 is a perspective view of the wind guide section 100 viewed from below. FIG. 11 is a perspective view of the wind guide section 100 shown in FIG. 9 taken in a horizontal section. In addition, in the drawings after FIG. 9, illustration of the above-mentioned electrical component EQ is omitted for convenience.

The first channel section 110 of the wind guide section 100 has a first channel main body section 111, an opening 112 on one end of the first channel, and an opening 113 on the other end of the first channel. The inside of the first channel main body portion 111 is hollow. A portion of the wind generated by the drive of the fan 91 passes through the inside of the first channel main body portion 111 . The first channel main body 111 may have any shape as long as it has a cavity through which wind passes, and its shape is not particularly limited.

The first flow path one end side opening 112 is an opening formed in the first flow path main body portion 111 at one end in the flow path direction through which the wind flows. In this embodiment, the opening 112 at one end of the first flow path is formed in a semicircular shape, but the shape is not particularly limited. The first flow path one end side opening 112 opens toward the radiator 92 (see FIG. 6) located on the right side with respect to the first flow path main body 111. That is, the opening 112 at one end of the first flow path is located at a position facing the radiator 92 . Therefore, it can be said that the first flow path one end side opening 112 is a first partial opening located at one end of the first flow path portion 110 on the radiator 92 side.

The first channel other end opening 113 is an opening formed at the other end of the first channel main body 111 in the direction of the channel through which the wind flows. In this embodiment, the opening 113 at the other end of the first flow path is formed in a rectangular shape, as shown in FIG. 9, but the shape is not particularly limited. The opening 113 at the other end of the first flow path opens downward. The first flow path other end side opening 113 is a second flow path located at the other end of the first flow path portion 110 on the opposite side from the first flow path one end side opening 112 which is the first partial opening. It can also be said that it is an opening.

The second flow path section 120 of the wind guiding section 100 has a second flow path main body 121, an opening 122 on one end of the second flow path, and an opening 123 on the other end of the second flow path. The inside of the second channel main body portion 121 is hollow. A part of the wind generated by the drive of the fan 91 passes through the inside of the second flow path main body part 121. The second channel main body 121 may have any shape as long as it has a cavity through which wind passes, and its shape is not particularly limited.

The second flow path one end side opening 122 is an opening formed in the second flow path main body portion 121 at one end in the flow path direction through which the wind flows. In this embodiment, the opening 122 at one end of the second flow path is formed in a semicircular shape, but the shape is not particularly limited. The second flow path one end side opening 122 opens toward the oil cooler 93 (see FIG. 6) located on the right side with respect to the second flow path main body 121. That is, the opening 122 at one end of the second flow path is located at a position facing the oil cooler 93. Therefore, it can be said that the second flow path one end side opening 122 is a second partial opening located at one end of the second flow path portion 120 on the oil cooler 93 side.

In the present embodiment, the opening 122 at one end of the second flow path has a shape that is continuously connected to the opening 112 at one end of the first flow path to form one circle (see FIG. 9). Therefore, if the first flow path one end side opening 112 and the second flow path one end side opening 122 are combined to form the first opening 100P, the wind guide section 100 has the first opening 100P. I can say that. It can be said that the first opening 100P has the first flow path one end side opening 112 as a first partial opening, and the second flow path one end side opening 122 as a second partial opening. Note that the first flow path one end side opening 112 and the second flow path one end side opening 122 may each be formed in a closed shape and spaced apart from each other.

The second flow path other end side opening 123 is an opening formed at the other end of the second flow path main body portion 121 in the flow path direction through which the wind flows. In this embodiment, the opening 123 at the other end of the second flow path is formed in a substantially rectangular shape, as shown in FIG. 9, but the shape is not particularly limited. The second flow path other end side opening 123 opens downward. The second channel other end side opening 123 is a third channel located at the other end of the second channel section 120 on the opposite side from the second channel one end side opening 122 which is the second partial opening. It can also be said that it is an opening.

Therefore, the wind guide section 100 includes a first opening 100P, an opening 113 on the other end side of the first flow path as a second opening, and an opening on the other end side of the second flow path as a third opening. It can also be said that it has 123.

The wind guide section 100 further includes a partition plate 130. That is, the hydraulic excavator 1 includes the partition plate 130. The partition plate 130 is a partition wall that partitions the first channel main body section 111 of the first channel section 110 and the second channel main body section 121 of the second channel section 120. In other words, the first channel main body 111 and the second channel main body 121 share the partition plate 130 as a partition wall. As shown in FIG. 4, the partition plate 130 is located between the radiator 92 and oil cooler 93, and the battery unit 53 when viewed from above. Further, as shown in FIG. 11, the partition plate 130 extends from the right side toward the left side, and then extends obliquely toward the left front in a bent manner. That is, the partition plate 130 crosses one direction (in this embodiment, the front-rear direction) that intersects the rotation axis CA of the fan (see FIG. 4), and in which the radiator 92 and the oil cooler 93 are positioned offset from each other. located.

At least a portion of the electric motor 61 (see FIG. 8) described above is arranged inside the first flow path section 110. FIG. 12 is a perspective view from below of the wind guide section 100 with the electric motor 61 accommodated in the first flow path section 110. In this embodiment, the electric motor 61 is located at the opening 113 on the other end side of the first flow path of the first flow path portion 110 and crosses the opening 113 on the other end side of the first flow path. Therefore, a part of the electric motor 61 is disposed inside the first flow path section 110. Note that the entire electric motor 61 may be disposed inside the first flow path section 110. The output shaft 61a of the electric motor 61 passes through a through hole 111a provided in the first channel body 111, and is connected to the input shaft of the hydraulic pump 71 (see FIG. 5, etc.).

Next, with reference to FIGS. 4 to 12, the flow of air (cooling air) generated by driving the fan 91 and the effects of the configuration of this embodiment will be described.

Air is sucked into the engine room 44 from the outside of the hydraulic excavator 1 by the rotation of the fan 91 about the rotation axis CA. Note that the drive type of the fan 91 in which air is sucked in from the outside is also referred to as a "suction type" here. The air sucked into the engine room 44 flows inside the housing 90 from the right side to the left side.

More specifically, a portion of the air sucked in from the outside by the fan 91 flows across the radiator 92 within the housing 90 . In other words, part of the air flows within the housing 90 through the gap between the radiators 92 or flows along the surface of the radiators 92 so as to overcome the radiators 92 . This cools the radiator 92. In other words, the refrigerant flowing through the radiator 92 is cooled by heat exchange.

Further, the remainder of the air sucked in by the fan 91 flows across the oil cooler 93 within the housing 90 . That is, the remainder of the air flows within the housing 90 through the gap between the oil coolers 93 or flows along the surface of the oil coolers 93 so as to overcome the oil coolers 93. This cools the oil cooler 93. In other words, the hydraulic oil flowing through the oil cooler 93 is cooled by heat exchange.

The wind that has cooled the radiator 92 (the wind that has licked the radiator 92 ) and the wind that has cooled the oil cooler 93 (the wind that has licked the oil cooler 93 ) flows toward the wind guide section 100 .

Here, as shown in FIG. 9, in the wind guide section 100, the first flow path section 110 and the second flow path section 120 are separated by a partition plate 130. The first flow path section 110 has a first flow path one end side opening 112 that opens toward the radiator 92 (see FIG. 6) at one end. Thereby, the wind after cooling the radiator 92 enters the inside of the first flow path portion 110 (first flow path main body portion 111) via the first flow path one end side opening 112. The wind that has flowed inside the first flow path section 110 is then discharged downward through the opening 113 on the other end side of the first flow path. An arrow W1 in FIG. 9 indicates a flow direction (path) of air after cooling the radiator 92 in the first flow path section 110.

Further, the second flow path section 120 has a second flow path one end side opening 122 that opens toward the oil cooler 93 at one end. Thereby, the air after cooling the oil cooler 93 enters the inside of the second flow path portion 120 (second flow path main body portion 121) via the second flow path one end side opening 122. The wind that has flowed inside the second flow path section 120 is then discharged downward through the opening 123 at the other end of the second flow path. An arrow W2 in FIG. 9 indicates a flow direction (path) of air after cooling the oil cooler 93 in the second flow path section 120.

By the way, high temperature (for example, about 90° C.) hydraulic oil used to drive the hydraulic actuator 73 (see FIG. 2) circulates and returns to the oil cooler 93. On the other hand, the temperature of the cooling water flowing through the radiator 92 is, for example, about 40° C., which is lower than the hydraulic oil flowing through the oil cooler 93. Therefore, the wind after cooling the radiator 92 has a relatively low temperature compared to the wind after cooling the oil cooler 93. This means that the wind flowing through the first passage section 110 (the wind after cooling the radiator 92) is relatively low temperature, and the wind flowing through the second passage section 120 (the wind after cooling the oil cooler 93). means a relatively high temperature.

Therefore, as shown in FIGS. 3 and 4, electrical components EQ such as the inverter 63 and the DC-DC converter 66 may be attached to the first flow path section 110, or as shown in FIG. By arranging the electric motor 61 in the opening 113 on the other end side, the relatively low-temperature wind flowing through the first flow path section 110 is used for cooling (air cooling) heat-generating components such as the electric component EQ and the electric motor 61. can do. Further, the relatively high temperature wind flowing through the second flow path section 120 can be discharged to the outside as it is (without hitting the heat generating component) via the opening 123 on the other end side of the second flow path.

As described above, since the radiator 92 and the oil cooler 93 overlap with the fan 91 when viewed from the direction of the rotation axis CA of the fan 91, the driving of one fan 91 causes both the radiator 92 and the oil cooler 93 to be You can apply the wind. Therefore, unlike the case where a plurality of fans are provided corresponding to each heat exchanger, the plurality of fans does not occupy the space for placing other members such as the battery unit. As a result, a compact layout suitable for the small electric hydraulic excavator 1 can be easily realized.

Furthermore, the partition plate 130 separates the space between the radiator 92 and oil cooler 93 and the battery unit 53 into one side and the other side in one direction (for example, the front-rear direction). This makes it possible to efficiently separate winds with different temperatures by the partition plate 130 and guide them to the respective spaces. Therefore, as in the present embodiment, the first flow path section 110 is arranged on one side in the above-mentioned one direction, and the electrical component EQ is attached to the first flow path section 110, and the opening on the other end side of the first flow path is arranged. By arranging the electric motor 61 at 113, one of the winds with different temperatures separated by the partition plate 130 (that is, the relatively low-temperature wind after cooling the radiator 92) is transferred to the heat generated by the electrical components EQ, etc. It can be applied to parts to cool heat-generating parts. In other words, one of the winds with different temperatures can be reused for cooling the heat generating components.

To summarize the above, according to the configuration of this embodiment, by using one fan 91 as a fan for cooling the radiator 92 and the oil cooler 93, a compact layout can be realized. Furthermore, the partition plate 130 can efficiently separate air having different temperatures so that it can be reused for cooling heat-generating components.

In a configuration in which the hydraulic excavator 1 includes a first flow path section 110 and a second flow path section 120 whose flow paths are separated by a partition plate 130, air after cooling the radiator 92 and after cooling the oil cooler 93 are used. From the viewpoint of efficiently sending the wind into the first flow path section 110 and the second flow path section 120, it is desirable that the first flow path section 110 and the second flow path section 120 are located as follows. That is, as shown in FIG. 4, the first flow path section 110 connects the radiator 92 and the battery unit 53 on one side in the one direction (for example, the rear side in the front-rear direction) separated by the partition plate when viewed from above. It is desirable to be located between. The second flow path section 120 is located between the oil cooler 93 and the battery unit 53 on the other side of the one direction (for example, the front side in the front-rear direction) separated by the partition plate 130 when viewed from above. It is desirable to do so.

Further, from the viewpoint of configuring the wind guiding section 100 compactly and obtaining the effects of the present embodiment described above, it is desirable that the first flow path section 110, the second flow path section 120, and the partition plate 130 are integrated. . From this point of view, it is desirable that the hydraulic excavator 1 includes the wind guide section 100 that holds the partition plate 130, and that the wind guide section 100 has the first flow path section 110 and the second flow path section 120.

The wind after cooling the radiator 92 and the wind after cooling the oil cooler 93 are guided into the inside of the wind guiding section 100, and these winds with different temperatures are discharged outside the machine through separate flow paths. Now, the wind guide section 100 includes the first opening 100P, the opening 113 on the other end side of the first flow path as the second opening, and the other end side of the second flow path as the third opening. It is desirable to have an opening 123. The first opening 100P includes a first passage opening 112 serving as a first partial opening located at one end of the first passage 110 on the radiator 92 side, and a first passage opening 112 at one end of the second passage 120. It is desirable to have an opening 123 at the other end of the second flow path as a second partial opening located at one end on the oil cooler 93 side.

FIG. 13 is a cross-sectional view of the first flow path portion 110 of the wind guiding portion 100 taken along a cross section passing through the electrical component EQ. Note that in FIG. 13, a DC-DC converter 66 is shown as the electrical component EQ. The electric motor 61 described above is located on the fan 91 side with respect to the battery unit 53. From the viewpoint of effectively utilizing the narrow space between the fan 91 and the battery unit 53 above the electric motor 61 as a space for arranging the electrical component EQ, the electrical component EQ is placed above the electric motor 61. It is desirable to be located.

In addition, from the viewpoint of reliably cooling the electrical component EQ by applying the wind flowing through the first flow path section 110, that is, the relatively low-temperature wind after cooling the radiator 92, to the electrical component EQ, the electrical component EQ is , is preferably held (attached) to the first flow path section 110.

Here, the DC-DC converter 66 as the electrical component EQ has a heat radiation section 66F. The heat dissipation section 66F is composed of, for example, a fin. From the viewpoint of increasing the cooling efficiency of the electrical components EQ by applying low-temperature wind (wind after cooling the radiator 92) to the heat dissipation section 66F, the heat dissipation section 66F may be located inside the first flow path section 110. desirable. That is, it is desirable to attach (embed) the electrical component EQ to the first flow path section 110 so that the heat dissipation section 66F is located inside the first flow path section 110.

Note that the configuration in which the heat dissipation section is located inside the first flow path section 110 is also applicable to the inverter 63 as the electrical component EQ. That is, as shown in FIG. 4, in the configuration in which the inverter 63 has the heat dissipation section 63F, from the viewpoint of improving cooling efficiency, the inverter 63 is placed in the first It is desirable to attach (embed) it to the flow path section 110.

From the viewpoint of effectively utilizing the relatively low-temperature wind after cooling the radiator 92 for cooling (air cooling) the electric motor 61, at least a portion of the electric motor 61 is , is preferably disposed inside the first flow path section 110. Furthermore, from the viewpoint of quickly discharging the air that has cooled the electric motor 61, it is desirable that the electric motor 61 be located at the opening 113 on the other end side of the first flow path as the second opening. Note that the electric motor 61 may be located below the opening 113 at the other end of the first flow path.

In addition, in order to increase the cooling efficiency of the electrical components EQ disposed in the first flow path portion 110, it is necessary to use relatively low-temperature air after cooling the radiator 92 to cool the oil cooler 93 and then generate relatively high-temperature air. It is desirable to maintain the temperature of the wind guided to the first flow path portion 110 (the wind after cooling the radiator 92) at a low temperature by preventing it from mixing with the wind on the upstream side of the partition plate 130. From this point of view, as shown in FIG. 4 and the like, it is desirable that the fan 91 be located on the opposite side of the partition plate 130 with respect to the radiator 92 and the oil cooler 93. It is desirable that the fan 91 blows air toward the radiator 92 and the oil cooler 93. In this configuration, the air after cooling the radiator 92 and the oil cooler 93 by air blowing from the fan 91 is distributed between two spaces (the first flow path section 110 and the second flow path section 120) separated by the partition plate 130. You will be guided almost directly to the inside). In other words, both winds are guided to the two spaces in a state where mixing on the upstream side of the partition plate 130 is reduced.

FIG. 14 is a perspective view showing the configuration of a modified example of the suction type. In addition, in FIG. 14, illustration of the 1st flow path part 110 of the wind guide part 100 is abbreviate|omitted for convenience. As shown in the figure, the fan 91 may be located on the partition plate 130 side with respect to the radiator 92 and the oil cooler 93. Even with this arrangement of the fan 91, by driving the fan 91, air from outside the machine is sucked in from the right side in the left-right direction (from the radiator 92 and oil cooler 93 side with respect to the fan 91), and the air is drawn in from the radiator 92 and oil cooler 93 side. There is no change in the fact that 93 can be cooled. Further, the wind that cools the radiator 92 and the wind that cools the oil cooler 93 are guided toward the partition plate 130 side, and the wind that is guided to one space separated by the partition plate 130 (for example, the air that cools the radiator 92 ) can be applied to the electrical equipment EQ to cool the electrical equipment EQ.

However, in this configuration, when the fan 91 is driven, air sucked in from the outside to cool the radiator 92 and air that cools the oil cooler 93 flow across the fan 91 toward the partition plate 130. Since the fan 91 is rotating, the wind that cools the radiator 92 and the wind that cools the oil cooler 93 may mix after crossing the fan 91 (before the partition plate 130). In this respect, as shown in FIG. 4 and the like, it is desirable that the fan 91 be located on the opposite side of the partition plate 130 with respect to the radiator 92 and the oil cooler 93 (on the opposite side of the battery unit 53).

As shown in FIG. 7, etc., the total width of the radiator 92 and the oil cooler 93 in one direction (for example, the front-back direction) intersecting the rotation axis CA is narrowed, and the radiator 92 and the oil cooler 93 are arranged compactly. In addition, it is desirable that the radiator 92 and the oil cooler 93 be located so as to partially overlap (when viewed from the direction of the rotation axis CA).

Furthermore, from the viewpoint of reliably cooling the radiator 92 and the oil cooler 93 at the same time by driving one fan 91, the radiator 92 and the oil cooler 93 are positioned overlapping the fan 91 when viewed from the direction of the rotation axis CA. In other words, it is desirable that the fan 91 be disposed facing the fan 91 .

In the present embodiment, the position of the fan 91 side end 130A (see FIGS. 4 and 11) of the partition plate 130 described above in the front-rear direction is not particularly limited. However, in a configuration in which the radiator 92 and the oil cooler 93 overlap in the direction of the rotation axis CA as in this embodiment, the air after cooling the radiator 92 and the air after cooling the oil cooler 93 are In order to increase separation efficiency, the fan 91 side end 130A of the partition plate 130 should be located opposite the overlapping region RV of the radiator 92 and the oil cooler 93 (see FIG. 4) in the direction of the rotation axis CA. is desirable. Note that in an arrangement where the radiator 92 and the oil cooler 93 do not overlap in the direction of the rotation axis CA (arrangement where they are lined up in the front-rear direction), the end portion 130A may be located opposite the boundary between the radiator 92 and the oil cooler 93. .

In this embodiment, an example has been described in which the wind guiding section 100 is applied to a suction type configuration, but it is also possible to apply the wind guiding section 100 to a discharge type configuration. The discharge type refers to a drive type of the fan 91 in which the air inside the engine room 44 is discharged to the outside by the drive of the fan 91. However, in the discharge type, the arrangement of the radiator 92 and oil cooler 93 is reversed from that of the suction type, or the flow path section where heat generating parts such as the electric component EQ and the electric motor 61 are arranged is reversed from the suction type. It is necessary to do so. In any case, in the case of the discharge type, the heat generating component may be disposed in the second flow path section 120.

[4. supplement〕
In the above description, the hydraulic excavator 1, which is a construction machine, has been described as an example of an electric working machine, but the electric working machine is not limited to the hydraulic excavator 1, and may be other construction machines such as a wheel loader. . Further, the electric working machine may be an agricultural machine such as a combine harvester or a tractor.

[5. Additional notes]
The hydraulic excavator 1 described in this embodiment can also be expressed as an electric working machine as described in the following supplementary notes.

The electric working machine mentioned in appendix (1) is
battery unit and
an electric motor driven by electric power supplied from the battery unit;
a first heat exchanger that cools a refrigerant passing through the battery unit;
a hydraulic pump that is driven by the electric motor and discharges hydraulic oil;
a second heat exchanger that cools the hydraulic oil;
a fan having a rotating shaft;
Comprising a partition plate,
The first heat exchanger and the second heat exchanger are positioned overlapping the fan when viewed from the direction of the rotation axis, and are positioned offset from each other in one direction intersecting the rotation axis,
The partition plate is located between the first heat exchanger, the second heat exchanger, and the battery unit when viewed from above, and is located across the one direction.

The electric working machine described in Supplementary note (2) is the electric working machine described in Supplementary note (1),
further comprising a first flow path section and a second flow path section whose flow paths are separated by the partition plate,
The first flow path section is located between the first heat exchanger and the battery unit on one side of the one direction separated by the partition plate when viewed from above,
The second flow path section is located between the second heat exchanger and the battery unit on the other side of the one direction separated by the partition plate when viewed from above.

The electric working machine set forth in Supplementary note (3) is the electric working machine set forth in Supplementary note (2),
further comprising a wind guide section that holds the partition plate,
The wind guide section has the first flow path section and the second flow path section.

The electric working machine described in appendix (4) is the electric working machine described in appendix (3),
The wind guiding section has a first opening, a second opening, and a third opening,
The first opening has a first partial opening and a second partial opening,
The first partial opening is located at one end on the first heat exchanger side in the first flow path section,
The second partial opening is located at one end of the second heat exchanger side in the second flow path section,
The second opening is located at the other end of the first flow path section opposite to the first partial opening,
The third opening is located at the other end of the second flow path section opposite to the second partial opening.

The electric working machine set forth in appendix (5) is the electric working machine set forth in appendix (4),
further comprising an electrical component to which the power is supplied from the battery unit,
The electrical component is held in the first flow path section.

The electric working machine set forth in Supplementary note (6) is the electric working machine set forth in Supplementary note (4) or (5),
The electric working machine according to claim 4 or 5, wherein at least a portion of the electric motor is located inside the first flow path section.

The electric working machine described in appendix (7) is the electric working machine described in appendix (6),
The electric motor is located at the second opening of the first flow path.

The electric working machine set forth in Supplementary note (8) is the electric working machine set forth in any of Supplementary notes (1) to (7),
The electric working machine according to any one of claims 1 to 7, wherein the fan is located on the opposite side of the partition plate with respect to the first heat exchanger and the second heat exchanger.

The electric working machine described in appendix (9) is the electric working machine described in appendix (8),
The fan blows air toward the first heat exchanger and the second heat exchanger.

The electric working machine set forth in Supplementary Note (10) is the electric working machine set forth in any one of Supplementary Notes (1) to (9),
The first heat exchanger and the second heat exchanger are located partially overlapping each other.

The electric working machine set forth in appendix (11) is the electric working machine set forth in appendix (10),
An end of the partition plate on the fan side is located opposite to an overlapping region of the first heat exchanger and the second heat exchanger in the direction of the rotation axis.

Although the embodiments of the present invention have been described above, the scope of the present invention is not limited thereto, and can be expanded or modified without departing from the gist of the invention.

INDUSTRIAL APPLICATION This invention can be utilized for working machines, such as a construction machine and an agricultural machine, for example.

1 Hydraulic excavator (electric working machine)
53 Battery unit 61 Electric motor 63 Inverter (electrical components)
66 DC-DC converter (electrical equipment)
71 Hydraulic pump 91 Fan 92 Radiator (first heat exchanger)
93 Oil cooler (second heat exchanger)
100 Wind guiding section 100P First opening 110 First flow path section 112 First flow path one end side opening (first partial opening)
113 Opening on the other end side of the first flow path (second opening)
120 Second flow path portion 122 Second flow path one end side opening (second partial opening)
123 Second channel other end side opening (third opening)
130 Partition plate 130A End CA Rotating shaft EQ Electrical components RV Overlapping area

Claims (11)

battery unit and
an electric motor driven by electric power supplied from the battery unit;
a first heat exchanger that cools a refrigerant passing through the battery unit;
a hydraulic pump that is driven by the electric motor and discharges hydraulic oil;
a second heat exchanger that cools the hydraulic oil;
a fan having a rotating shaft;
Comprising a partition plate,
The first heat exchanger and the second heat exchanger are positioned overlapping the fan when viewed from the direction of the rotation axis, and are positioned offset from each other in one direction intersecting the rotation axis,
In the electric working machine, the partition plate is located between the first heat exchanger, the second heat exchanger, and the battery unit, and is located across the one direction when viewed from above. further comprising a first flow path section and a second flow path section whose flow paths are separated by the partition plate,
The first flow path portion is located between the first heat exchanger and the battery unit on one side of the one direction separated by the partition plate when viewed from above,
The second flow path section is located between the second heat exchanger and the battery unit on the other side of the one direction separated by the partition plate when viewed from above. electric working machines. further comprising a wind guide section that holds the partition plate,
The electric working machine according to claim 2, wherein the wind guide section has the first flow path section and the second flow path section. The wind guiding section has a first opening, a second opening, and a third opening,
The first opening has a first partial opening and a second partial opening,
The first partial opening is located at one end on the first heat exchanger side in the first flow path section,
The second partial opening is located at one end of the second heat exchanger side in the second flow path section,
The second opening is located at the other end of the first flow path section opposite to the first partial opening,
The electric working machine according to claim 3, wherein the third opening is located at the other end of the second flow path portion on the opposite side to the second partial opening. further comprising an electrical component to which the power is supplied from the battery unit,
The electric working machine according to claim 4, wherein the electrical component is held in the first flow path section. The electric working machine according to claim 4, wherein at least a portion of the electric motor is located inside the first flow path section. The electric working machine according to claim 6, wherein the electric motor is located at the second opening of the first flow path section. The electric working machine according to claim 1, wherein the fan is located on the opposite side of the partition plate with respect to the first heat exchanger and the second heat exchanger. The electric working machine according to claim 8, wherein the fan blows air toward the first heat exchanger and the second heat exchanger. The electric working machine according to any one of claims 1 to 9, wherein the first heat exchanger and the second heat exchanger are located partially overlapping each other. The electric type according to claim 10, wherein an end of the partition plate on the fan side is located opposite to an overlapping area of the first heat exchanger and the second heat exchanger in the direction of the rotation axis. working machine.