Patent Description:
Conventionally, an electric work machine including an electric motor and a hydraulic pump has been proposed. For example, Patent Document <NUM> discloses an electric work machine in which an electric motor and a hydraulic pump are arranged below a battery unit that supplies electric power to the electric motor.

Patent Document <NUM>: <CIT>. Patent document <CIT> shows an other arrangement.

The hydraulic pump is driven by the electric motor and pumps hydraulic oil to a hydraulic actuator. The hydraulic oil is contained in a hydraulic oil tank. In a configuration of Patent Document <NUM>, the hydraulic oil tank is arranged on a side of the battery unit. Therefore, there is room for improvement in achieving a layout suitable for a small-sized electric work machine, i.e., a compact layout including the hydraulic oil tank and the battery unit. In particular, even when the battery unit is increased in size in order to increase a capacity of the battery unit in a small-sized electric work machine, it is necessary to secure a space for arranging the hydraulic oil tank separately from the battery unit in the configuration of Patent Document <NUM>. For this reason, it is more difficult to achieve the compact layout, and it may become difficult to increase the capacity of the battery unit.

In addition, when the electric motor and the hydraulic pump are driven, heat is generated, and the hydraulic oil flowing through the hydraulic actuator also reaches a high temperature and therefore, the hydraulic oil tank that contains the hydraulic oil also reaches a high temperature. In order to ensure cooling performance of the electric motor, the hydraulic pump, and the hydraulic oil tank, it is desirable to achieve a layout which also takes into consideration cooling efficiency in cooling these components.

The present invention has been made in order to solve the above problems, and an object of the present invention is to provide an electric work machine that has a compact layout and facilitates an increase in capacity of a battery unit while also taking into consideration the cooling efficiency in cooling an electric motor, a hydraulic pump, and a hydraulic oil tank.

An electric work machine according to one aspect of the present invention includes an electric motor, a battery unit that stores electric power for driving the electric motor, a hydraulic oil tank that contains hydraulic oil, and a hydraulic pump that is driven by the electric motor and is connected to the hydraulic oil tank, where the electric motor, the hydraulic pump, and the hydraulic oil tank are arranged below the battery unit on a machine body frame and are arranged side by side in a lateral direction of the machine body frame, according to claims <NUM> or <NUM>.

It is possible to achieve an electric work machine that has a compact layout and facilitates an increase in capacity of the battery unit while also taking into consideration cooling efficiency when cooling the electric motor, the hydraulic pump, and the hydraulic oil tank.

An embodiment of the present invention will be described as follows with reference to the drawings.

<FIG> is a side view illustrating a schematic configuration of a hydraulic excavator (electric excavator) <NUM> provided as an example of an electric work machine according to the present embodiment. <FIG> is a rear view of the hydraulic excavator <NUM>. The hydraulic excavator <NUM> includes a lower traveling body <NUM>, a work machine <NUM>, and an upper turning body <NUM>.

Here, in this embodiment, each direction is defined as follows. A forward direction is a direction in which an operator (manipulator, driver) seated on a driver seat 41a of the upper turning body <NUM> faces front, and a backward direction is a direction opposite to the forward direction. Therefore, in a state where the upper turning body <NUM> does not turn with respect to the lower traveling body <NUM> (<NUM> degree turning angle), a front-back direction of the upper turning body <NUM> coincides with a direction in which the lower traveling body <NUM> moves forward and backward. As viewed from the operator seated on the driver seat 41a, a left side is defined as "left" and a right side is defined as "right". A gravity direction perpendicular to the front-back direction and a left-right direction is defined as an up-down direction, in which an upstream side of the gravity direction is defined as "up", and a downstream side thereof is defined as "down". In the drawings, the hydraulic excavator <NUM> is illustrated in a state where the upper turning body <NUM> does not turn with respect to the lower traveling body <NUM>. Further, in the drawings, as necessary, a forward is denoted by a symbol "F", likewise, backward by "B", rightward by "R", leftward by "L", upward by "U", and downward by "D".

The lower traveling body <NUM> includes a pair of left and right crawlers <NUM> and a pair of left and right traveling motors <NUM>. Each of the traveling motors <NUM> is a hydraulic motor. The left and right traveling motors <NUM> drive the left and right crawlers <NUM>, respectively, thereby allowing the hydraulic excavator <NUM> to move forward and backward. The lower traveling body <NUM> is provided with a blade <NUM> for performing a ground leveling work and a blade cylinder 23a. The blade cylinder 23a is a hydraulic cylinder that rotates the blade <NUM> in the up-down direction.

The work machine <NUM> includes a boom <NUM>, an arm <NUM>, and a bucket <NUM>. The boom <NUM>, the arm <NUM>, and the bucket <NUM> can be independently driven, thereby enabling to perform excavation work of earth, sand, and the like.

The boom <NUM> is rotated by a boom cylinder 31a. The boom cylinder 31a has a base end portion thereof supported by a front portion of the upper turning body <NUM>, and is movable freely in an extendable and retractable manner. The arm <NUM> is rotated by an arm cylinder 32a. The arm cylinder 32a has a base end portion thereof supported by the boom <NUM>, and is movable freely in an extendable and retractable manner. The bucket <NUM> is rotated by a bucket cylinder 33a. The bucket cylinder 33a has a base end portion thereof supported by the arm <NUM>, and is movable freely in an extendable and retractable manner.

The boom cylinder 31a, the arm cylinder 32a, and the bucket cylinder 33a each include a hydraulic cylinder.

The upper turning body <NUM> is located above the lower traveling body <NUM> and provided capable of turning with respect to the lower traveling body <NUM> via a turning bearing (not illustrated). In the upper turning body <NUM>, a steering unit <NUM>, a turning frame <NUM>, a turning motor <NUM>, and an engine room <NUM> are arranged. By driving of the turning motor <NUM> as a hydraulic motor, the upper turning body <NUM> turns via a turning bearing. The hydraulic excavator <NUM> includes the turning frame <NUM> as a machine body frame.

The upper turning body <NUM> includes a hydraulic pump <NUM> (see <FIG>) arranged. Namely, the hydraulic excavator <NUM> includes the hydraulic pump <NUM>. The hydraulic pump <NUM> is driven by an electric motor <NUM> (see <FIG>, etc.) inside the engine room <NUM>. The hydraulic pump <NUM> supplies a hydraulic oil (pressure oil) to hydraulic motors (for example, the left and right traveling motors <NUM> and the turning motor <NUM>), and hydraulic cylinders (for example, the blade cylinder 23a, the boom cylinder 31a, the arm cylinder 32a, and the bucket cylinder 33a). The hydraulic motors and the hydraulic cylinders that are driven with the hydraulic oil supplied from the hydraulic pump <NUM> are collectively referred to as a hydraulic actuator <NUM> (see <FIG>).

The steering unit <NUM> is installed on the turning frame <NUM>. The driver seat 41a is arranged on the steering unit <NUM>. Various levers 41b are arranged around the driver seat 41a. The operator is seated on the driver seat 41a and operates the lever 41b, thereby driving the hydraulic actuator <NUM>. This allows the lower traveling body <NUM> to travel, the blade <NUM> to perform a ground leveling work, the work machine <NUM> to perform an excavation work, the upper turning body <NUM> to turn, and the like.

A battery unit <NUM> is arranged on the upper turning body <NUM>. Namely, the hydraulic excavator <NUM> includes the battery unit <NUM>. The battery unit <NUM> is composed of, for example, a lithium-ion battery unit, and stores electric power for driving the electric motor <NUM>. The battery unit <NUM> may be composed of a plurality of batteries as a unit or may be composed of a single battery cell. In the present embodiment, the battery unit <NUM> is composed of three batteries as a unit (see <FIG>), but the number of batteries to be unitized is not limited to the above three.

Moreover, the upper turning body <NUM> is provided with a power feed port, which is not illustrated. The above-mentioned power feed port and an external power source (commercial power source) are connected via a power feed cable. This allows charging of the battery unit <NUM>.

The upper turning body <NUM> is further provided with a lead battery <NUM>. The lead battery <NUM> outputs a low voltage (<NUM> V, for example) DC voltage. The output from the lead battery <NUM> is supplied as a control voltage to, for example, a system controller <NUM> (see <FIG>), a drive unit of a fan <NUM> (see <FIG>), and the like.

The hydraulic excavator <NUM> may be configured by using hydraulic equipment such as the hydraulic actuator <NUM> and an actuator driven by electric power, in combination. As the actuator driven by electric power, for example, an electric traveling motor, an electric cylinder, and an electric turning motor are included.

<FIG> is a block diagram schematically illustrating a configuration of electric and hydraulic systems of the hydraulic excavator <NUM>. The hydraulic excavator <NUM> includes the electric motor <NUM>, a charger <NUM>, an inverter <NUM>, and a Power Drive Unit (PDU) <NUM>, a junction box <NUM>, a DC-DC converter <NUM>, and a system controller <NUM>. The system controller <NUM> is composed of an electronic control unit also called an Electronic Control Unit (ECU) and electrically controls each unit of the hydraulic excavator <NUM>. The charger <NUM>, the inverter <NUM>, the junction box <NUM>, the DC-DC converter <NUM>, and the above-mentioned lead battery <NUM> are also collectively referred to as electrical equipment EQ.

The electric motor <NUM> is driven by electric power supplied from the battery unit <NUM> via the junction box <NUM> and the inverter <NUM>. The electric motor <NUM> is composed of a permanent magnet motor or an induction motor. The electric motor <NUM> is arranged (vibration-isolation supported) above the turning frame <NUM> (see <FIG>).

The charger <NUM> converts an AC voltage supplied from the external power source via the power feed cable into a DC voltage. The inverter <NUM> converts a DC voltage supplied from the battery unit <NUM> into an AC voltage and supplies the AC voltage to the electric motor <NUM>. This rotates the electric motor <NUM>. The AC voltage (current) from the inverter <NUM> to the electric motor <NUM> is supplied based on a rotation instruction being output from the system controller <NUM>.

The PDU <NUM> is a battery control unit that controls input and output of the battery unit <NUM> by controlling an internal battery relay, and is also called a power management unit (PMU). The junction box <NUM> is configured by including a charger relay, an inverter relay, a fuse, and the like. The voltage being output from the above-mentioned charger <NUM> is supplied to the battery unit <NUM> via the junction box <NUM> and the PDU <NUM>. The voltage being output from the battery unit <NUM> is supplied to the inverter <NUM> via the PDU <NUM> and the junction box <NUM>.

The DC-DC converter <NUM> lowers a high-voltage (<NUM> V, for example) DC voltage supplied from the battery unit <NUM> via the junction box <NUM> to a low voltage (<NUM> V, for example). Similar to the output from the lead battery <NUM>, the voltage being output from the DC-DC converter <NUM> is supplied to the system controller <NUM>, the drive unit of the fan <NUM>, and the like. In the present embodiment, a plurality of the DC-DC converters <NUM> are provided (see <FIG>), but a single DC-DC converter <NUM> may be provided.

The hydraulic pump <NUM> is connected to a rotary shaft (output shaft) of the electric motor <NUM>. The hydraulic pump <NUM> is connected to a hydraulic oil tank <NUM> that contains (stores) hydraulic oil via a hydraulic hose <NUM> (see <FIG> and <FIG>). Namely, the hydraulic excavator <NUM> includes the hydraulic oil tank that contains hydraulic oil. The hydraulic pump <NUM> causes the hydraulic oil in the hydraulic oil tank <NUM> to be supplied to the hydraulic actuator <NUM> via a control valve <NUM>. As a result, the hydraulic actuator <NUM> is driven. The control valve <NUM> is a direction switch valve that controls a flow direction and a flow rate of the hydraulic oil supplied to the hydraulic actuator <NUM>.

<FIG> is a plan view illustrating a configuration of an inside of the engine room <NUM>. <FIG> is a perspective view of the inside of the engine room <NUM> as viewed obliquely from a rear upper side. <FIG> is a perspective view of the inside of the engine room <NUM> as viewed obliquely from a rear lower side. The arrangement of the above-mentioned components in the engine room <NUM> will be described below. In the engine room <NUM>, each component is supported on the turning frame <NUM> via a support member such as a stay, but the support member is not illustrated in the drawings for the purpose of clarifying an arrangement position of each component.

As illustrated in <FIG>, the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM> are arranged below the battery unit <NUM> on the turning frame <NUM>. Further, the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM> are arranged in this order from a right side to a left side of the turning frame <NUM> below the battery unit <NUM>. In other words, the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM> are arranged side by side in a lateral direction (left-right direction) of the turning frame <NUM>. At this time, the electric motor <NUM> is arranged on the right side (one side) in the lateral direction, and the hydraulic oil tank <NUM> is arranged on the left side (another side) in the lateral direction.

The charger <NUM> is arranged above the turning frame <NUM> and behind the battery unit <NUM>. The lead battery <NUM> is arranged above the turning frame <NUM> and behind the hydraulic pump <NUM>. In other words, the lead battery <NUM> is arranged even further below the charger <NUM>. The inverter <NUM> is arranged behind the battery unit <NUM> and between the charger <NUM> and the lead battery <NUM>.

The junction box <NUM> is arranged even further below the inverter <NUM> and even further behind the electric motor <NUM>. The DC-DC converter <NUM> is arranged behind the junction box <NUM>. The PDU <NUM> is arranged on a right side of the battery unit <NUM> (see <FIG>).

The fan <NUM> is arranged in the engine room <NUM> that contains the battery unit <NUM>. Namely, the hydraulic excavator <NUM> includes the engine room <NUM> and the fan <NUM>. The fan <NUM> is an electric fan, and generates a wind flow in the engine room <NUM>. In the present embodiment, the fan <NUM> includes a first fan 81a and a second fan 81b. The first fan 81a is arranged behind the battery unit <NUM>. The second fan 81b is arranged behind the battery unit <NUM> and below the first fan 81a.

When the fan <NUM> (the first fan 81a and the second fan 81b) is driven, air is sucked into the engine room <NUM> from two vent holes 44R1 and 44R2 (both are second openings; see <FIG>) provided in a right hood 44R serving as a sidewall on the right side of the engine room <NUM>. The sucked air flows from the right side toward the left side in the engine room <NUM>, and is discharged to the outside through two exhaust ports 44B1 and 44B2 (both are first openings; see <FIG>) provided in a rear hood 44B serving as a rear wall of the engine room <NUM>. The two vent holes 44R1 and 44R2 are vertically arranged side by side in the right hood 44R. The two exhaust ports 44B1 and 44B2 are vertically arranged side by side in the rear hood 44B, and are arranged facing the first fan 81a and the second fan 81b, respectively. The right hood 44R is detachably connected to a right end of the rear hood 44B.

The components (including the electric motor <NUM>, the battery unit <NUM>, etc.) arranged in the engine room <NUM> can be cooled (air-cooled) by the flow of air in the engine room <NUM>.

In the present embodiment, as described above, the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM> are arranged below the battery unit <NUM> on the turning frame <NUM>, and are arranged side by side in the lateral direction of the turning frame <NUM>. Thus, a space below the battery unit <NUM> on the turning frame <NUM> can be effectively utilized as a space for arranging the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM>. Therefore, in the small-sized hydraulic excavator <NUM>, it is possible to achieve a compact layout including the hydraulic oil tank <NUM> and the battery unit <NUM>, for example, as compared with a configuration in which the hydraulic oil tank <NUM> is arranged on a side of the battery unit <NUM>.

Further, in the present embodiment, even when the battery unit <NUM> is increased in capacity (increased in size) in the small-sized hydraulic excavator <NUM>, only the battery unit <NUM> can be increased in size while the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM> are arranged below the battery unit <NUM>. This facilitates an increase in size of the battery unit <NUM>, i.e., an increase in capacity of the battery unit <NUM>, while keeping the layout compact as described above.

Further, even in an assumed case in which the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM> are arranged side by side in the lateral direction of the turning frame <NUM>, thereby driving the fan <NUM> and cooling (air-cooling) the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM>, the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM>, which are located below the battery unit <NUM>, can be collectively and efficiently cooled by wind blown in the lateral direction of the turning frame <NUM>.

Therefore, according to the arrangement of the electric motor <NUM> and the like according to the present embodiment, it is possible to achieve the small-sized hydraulic excavator <NUM> having a compact layout and capable of facilitating an increase in capacity of the battery unit <NUM> while taking into consideration a cooling efficiency of the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM>.

From the viewpoint of cooling the electric motor <NUM> and the hydraulic oil tank <NUM> in a well-balanced manner, it is desirable to cool the electric motor <NUM> having a relatively low temperature first and then cool the hydraulic oil tank <NUM> having a relatively high temperature by wind blown by the fan <NUM>. For this purpose, it is desirable that the electric motor <NUM> and the hydraulic oil tank <NUM> are arranged on opposite sides to each other in the lateral direction on the turning frame <NUM>. In other words, as illustrated in <FIG> and the like, the electric motor <NUM> and the hydraulic oil tank <NUM> are desirably arranged on one side (for example, the right side) and another side (for example, the left side) in the lateral direction, respectively, on the turning frame <NUM>.

In addition, from the viewpoint of cooling the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM> in a well-balanced manner, it is desirable to cool the electric motor <NUM> having a relatively low temperature first, and then cool the hydraulic pump <NUM> having a high temperature, and finally cool the hydraulic oil tank <NUM> having the highest temperature by wind blown by the fan <NUM>. For this purpose, as shown in <FIG> and the like, the hydraulic pump <NUM> is desirably arranged between the electric motor <NUM> and the hydraulic oil tank <NUM>.

From the viewpoint of avoiding an increase in lateral dimension of the engine room <NUM> due to the installation of the fan <NUM>, the fan <NUM> is desirably arranged behind the battery unit <NUM>. In short, it is desirable that the fan <NUM> be arranged between the battery unit <NUM> and the rear hood 44B serving as the rear wall of the engine room <NUM>.

In addition, it is desirable that the fan <NUM> be arranged in the vicinity of the hydraulic oil tank <NUM> in the engine room <NUM> from the viewpoint of efficiently cooling the hydraulic oil tank by efficiently making wind hit the hydraulic oil tank <NUM>, which tends to have a high temperature, by driving the fan <NUM>. In this respect, it is desirable that the fan <NUM> be arranged on a side of the hydraulic oil tank <NUM> in the lateral direction in the engine room <NUM>. In short, the fan <NUM> is desirably arranged on another side in the lateral direction in the engine room <NUM>.

From the viewpoint of cooling the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM> in this order in a well-balanced manner in the engine room <NUM>, it is desirable to generate a flow of wind from a side of the electric motor <NUM> toward the hydraulic oil tank <NUM> side in the engine room <NUM>. For this purpose, it is desirable that, when the fan <NUM> is driven, air is sucked into the engine room <NUM> from the vent holes 44R1 and 44R2 (second openings) close to the electric motor <NUM>, and the air is discharged to the outside of the engine room <NUM> from the exhaust ports 44B1 and 44B2 close to the hydraulic oil tank <NUM>. From this point of view, it is desirable that the exhaust ports 44B1 and 44B2 as the first openings be provided at a position facing the fan <NUM> in the rear hood 44B serving as the rear wall of the engine room <NUM>. Further, it is desirable that the right hood 44R as a sidewall connected to the rear hood 44B of the engine room <NUM> and located on one side (for example, the right side) in the lateral direction with respect to the rear hood 44B is provided with the vent holes 44R1 and 44R2 as the second openings.

From the viewpoint of simultaneously and efficiently cooling the battery unit <NUM>, the electric motor <NUM> arranged below the battery unit <NUM>, and the like, it is desirable to cool the battery unit <NUM>, the electric motor <NUM>, and the like by wind generated by the driving of separate fans <NUM>. In short, it is desirable to cool the battery unit <NUM> by the wind generated by the driving of the first fan 81a. Further, it is desirable to cool the electric motor <NUM> and the like arranged below the battery unit <NUM> by the wind generated by the driving of the second fan 81b arranged below the first fan 81a. Therefore, the fan <NUM> desirably includes the first fan 81a and the second fan 81b arranged side by side in the up-down direction in the engine room <NUM>.

In the present embodiment, as illustrated in <FIG> and <FIG>, the hydraulic excavator <NUM> further includes an oil cooler <NUM>. The oil cooler <NUM> is a heat exchanger that cools the hydraulic oil by heat exchange, and is arranged in the engine room <NUM>. Further, the oil cooler <NUM> is connected to a hydraulic oil tank <NUM> and supplies the cooled hydraulic oil to the hydraulic oil tank <NUM>. It is desirable that the oil cooler <NUM> be arranged between the fan <NUM> and the first opening from the viewpoint of making the wind generated in the engine room <NUM> by the driving of the fan <NUM> hit the oil cooler <NUM> and effectively utilizing the wind for cooling the oil cooler <NUM> and from the viewpoint of efficiently discharging the wind after hitting the oil cooler <NUM> to the outside via the exhaust ports 44B1 and 44B2 (first openings).

Herein, for example, the wind used for cooling the hydraulic oil tank <NUM> arranged below the battery unit <NUM> is increased in temperature by the high-temperature hydraulic oil tank <NUM>. For this reason, when the wind generated by the driving of the second fan 81b arranged below hits the oil cooler <NUM>, the wind that has increased in temperature after hitting the hydraulic oil tank <NUM> hits the oil cooler <NUM>, and there is concern that the cooling efficiency of the oil cooler <NUM> will decrease.

Therefore, from the viewpoint of efficiently cooling the oil cooler <NUM>, it is desirable to make the wind (having a relatively low temperature) used for cooling the battery unit <NUM> located above the hydraulic oil tank <NUM> hit the oil cooler <NUM>. In this respect, it is desirable that the oil cooler <NUM> be arranged between the first fan 81a located at the uppermost part and the first opening (particularly, the exhaust port 44B1).

When the wind generated by the driving of the fan <NUM> and used for cooling the battery unit <NUM> and the like in the engine room <NUM> can be effectively utilized for cooling the electrical equipment EQ (the charger <NUM>, the inverter <NUM>, the junction box <NUM>, the DC-DC converter <NUM>, and the lead battery <NUM>), a fan dedicated to cooling the electrical equipment EQ is not required, which is desirable in that the configuration can be simplified. In this respect, it is desirable that the electrical equipment EQ is arranged on a side (for example, the right side) of the fan <NUM>.

In this case, since the wind generated by the driving of the fan <NUM> flows against the electrical equipment EQ (hits the electrical equipment EQ or flows along a surface of the electrical equipment EQ) in the engine room <NUM>, the electrical equipment EQ is cooled (air-cooled).

In the present embodiment, an example in which the electric motor <NUM>, the hydraulic pump <NUM>, and the hydraulic oil tank <NUM> are arranged in this order from the right side toward the left side in the lateral direction in the engine room <NUM> has been described, but the components may be arranged in this order from the left side toward the right side in the lateral direction. In other words, one side in the lateral direction may be the left side, and another side in the lateral direction may be the right side. In this case, the arrangement of the components in the lateral direction of the turning frame <NUM> may be reversed from that in the present embodiment.

The hydraulic excavator <NUM>, which is a construction machine, has been described as the example of the electric work machine in the present embodiment, but the electric work machine is not limited to the hydraulic excavator <NUM> and may be any other construction machine such as a wheel loader. The electric work machine may be an agricultural machine such as a combine harvester or a tractor.

The hydraulic excavator <NUM> described in the present embodiment can also be referred to as an electric work machine as illustrated in the following supplementary notes.

An electric work machine according to supplementary note (<NUM>) includes: an electric motor, a battery unit that stores electric power for driving the electric motor; a hydraulic oil tank that contains hydraulic oil; and a hydraulic pump that is driven by the electric motor and connected to the hydraulic oil tank, where the electric motor, the hydraulic pump, and the hydraulic oil tank are arranged below the battery unit on a machine body frame and are arranged side by side in a lateral direction of the machine body frame.

An electric work machine according to supplementary note (<NUM>) is the electric work machine according to supplementary note (<NUM>), where the electric motor and the hydraulic oil tank are respectively arranged on one side and another side in the lateral direction on the machine body frame.

An electric work machine according to supplementary note (<NUM>) is the electric work machine according to supplementary note (<NUM>), where the hydraulic pump is arranged between the electric motor and the hydraulic oil tank.

An electric work machine according to supplementary note (<NUM>) is the electric work machine according to supplementary note (<NUM>) or (<NUM>), further including: an engine room that contains the battery unit (and also contains the electric motor and the hydraulic pump); and a fan that generates a flow of wind in the engine room, where the fan is arranged between the battery unit and a rear wall of the engine room.

An electric work machine according to supplementary note (<NUM>) is the electric work machine according to supplementary note (<NUM>), where the fan is arranged on the another side in the lateral direction in the engine room.

An electric work machine according to supplementary note (<NUM>) is the electric work machine according to supplementary note (<NUM>), where a first opening is provided at a position facing the fan in the rear wall of the engine room and a second opening is provided in a side wall connected to the rear wall of the engine room and located on one side in the lateral direction with respect to the rear wall.

An electric work machine according to a supplementary note (<NUM>) is the electric work machine according to the supplementary note (<NUM>), where the fan includes a first fan and a second fan arranged side by side in a vertical direction in the engine room.

An electric work machine according to supplementary note (<NUM>) is the electric work machine according to supplementary note (<NUM>), where an oil cooler for cooling the hydraulic oil is arranged between the fan and the first opening.

An electric work machine according to supplementary note (<NUM>) is the electric work machine according to supplementary note (<NUM>), where the oil cooler is arranged between the first fan located at the uppermost part and the first opening.

An electric work machine according to supplementary note (<NUM>) is the electric work machine according to any one of supplementary notes (<NUM>) to (<NUM>), further including electrical equipment arranged on a side (in a lateral direction) of the fan.

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

Claim 1:
An electric work machine (<NUM>) comprising: an electric motor (<NUM>); a battery unit (<NUM>) that stores electric power for driving the electric motor; a hydraulic oil tank (<NUM>) that contains hydraulic oil; and a hydraulic pump (<NUM>) that is driven by the electric motor and is connected to the hydraulic oil tank, wherein the electric motor, the hydraulic pump, and the hydraulic oil tank are arranged below the battery unit on a machine body frame (<NUM>) and are arranged side by side in a lateral direction of the machine body frame, characterized in that the electric motor (<NUM>) and the hydraulic oil tank (<NUM>) are respectively arranged on one side and another side in the lateral direction on the machine body frame (<NUM>).