Small electric excavator

Abstract

An aspect of the present disclosure provides a small electric excavator including a lower traveling body, an upper rotating body, and a working device, wherein: the upper rotating body includes a vehicle body frame, a cabin installed on the left side on the vehicle body frame, and a counterweight installed on the rear side of the vehicle body frame; inside the vehicle body frame, with respect to a center line, a MCV and a hydraulic tank are disposed on the left side and a cooling fan, a radiator, an oil cooler, a battery, an electric motor, a hydraulic pump, and electric devices are disposed on the right side; at least one inlet through which cold air is introduced is formed in the vehicle body frame; an outlet through which hot air is discharged is formed in a front surface portion of the vehicle body frame; and the cooling fan is disposed directly behind the outlet so as to be configured in a manner of blowing air inside the vehicle body frame forward.

Description

compact electric excavator

[0001] The present disclosure generally relates to a small electric excavator. In particular, the present disclosure relates to a small electric excavator having a structure and arrangement that can improve the cooling efficiency of internal components. The present disclosure can be applied to large vehicles, such as trucks, buses, and construction equipment, among other vehicle types. While the present disclosure may be described with respect to a specific vehicle, the present disclosure is not limited to any particular vehicle.

[0002] An excavator is a type of construction machine that performs various tasks, such as digging the ground at construction sites, loading soil, excavating for foundations, demolishing buildings, leveling the ground, and leveling the ground. Such construction machines may generally include an undercarriage that functions as a moving device, an upper swivel body that is swivellably mounted on the lower swivel body, and a work device mounted at the front of the upper swivel body.

[0003] Conventional excavators are usually equipped with an engine such as a diesel engine to obtain driving power, and the power of this engine is used to drive a hydraulic pump, and the hydraulic oil discharged from the hydraulic pump is supplied to a hydraulic actuator such as a hydraulic motor or hydraulic cylinder, thereby rotating the driving crawler or tires or operating equipment such as a boom, arm, or bucket.

[0004] Conventional excavators equipped with engines like diesel engines suffer from high fuel costs and high fuel consumption, which increases operating costs. Furthermore, there is a persistent demand for stricter exhaust gas regulations for construction equipment, increased demand for low-noise equipment, and lower maintenance costs.

[0005] Accordingly, relatively efficient and environmentally friendly compact electric excavators are emerging to improve energy efficiency and work performance. However, these compact electric excavators have limited internal space, leaving little room for components. Therefore, efficient placement of each component is crucial. For example, considering the location of the battery module, it is desirable to place the cooling device in a direction that does not affect battery cooling. Furthermore, compact electric excavators require various electrical devices (motors, inverters, converters, various ECUs, etc.) other than the battery to be placed within the frame, so heat generation from each component must also be managed. While the engine was the largest heat source in conventional excavators, in electric excavators, the largest heat source is the various devices that use hydraulic oil (hydraulic tank, main control valve (MCV), hydraulic pump, etc.). Therefore, in order to efficiently manage the heat of each component placed inside a small electric excavator, it is important to determine how to place the inlet section where cold air flows in and the outlet section where the heated air passes through each component and the radiator and is discharged.

[0006] The present disclosure is intended to solve the problems of the prior art described above, and an object of the present disclosure is to provide a small electric excavator having a structure and arrangement capable of improving the cooling efficiency of internal components.

[0007] A first aspect of the present disclosure provides a small electric excavator including a lower body, an upper slewing body, and a work device, wherein the upper slewing body includes a body frame, a cabin installed on the left side of the body frame, and a counterweight installed on the rear side of the body frame, and inside the body frame, an MCV and a hydraulic tank are arranged on the left side with respect to the centerline, and a cooling fan, a radiator, an oil cooler, a battery, an electric motor, a hydraulic pump, and electric devices are arranged on the right side, and at least one inlet for introducing cold air is formed in the body frame, an outlet for discharging heated air is formed in the front part of the body frame, and the cooling fan is arranged immediately behind the outlet and configured to blow the internal air of the body frame forward.

[0008] In some examples, optionally including at least one preferred example, the radiator and the oil cooler may be positioned directly behind the cooling fan, which may be a small electric excavator.

[0009] In some examples, optionally including at least one preferred example, the MCV may be a small electric excavator characterized in that it is arranged on the left front side with respect to the centerline inside the body frame, and ventilation is formed on the lower part of the body frame where the MCV is located so that heat generated from the MCV can circulate.

[0010] In some examples, optionally including at least one preferred example, a small electric excavator may be characterized in that a baffle is installed inside the body frame to at least partially block the inflow of air from the left to the right with respect to the centerline.

[0011] In some examples, including at least one preferred example, the hydraulic tank may be disposed at the left rear side with respect to the centerline inside the body frame, and a third inlet is formed on the lower part of the body frame where the hydraulic tank is located to allow air to be introduced for cooling the hydraulic tank, which may be a small electric excavator.

[0012] In some examples, optionally including at least one preferred example, the electric motor, the hydraulic pump and the electric devices are arranged at the right rear side with respect to the centerline inside the body frame, and a first inlet is formed at the rear of the body frame to allow air to be introduced for cooling the electric motor, the hydraulic pump and the electric devices, which may be a small electric excavator.

[0013] In some examples, optionally including at least one preferred example, the battery may be disposed behind the radiator and the oil cooler, and a second inlet is formed on the right side of the body frame to allow air to flow in for cooling the battery, which may be a small electric excavator.

[0014] In some examples, optionally including at least one preferred example, a small electric excavator may be characterized in that a fourth inlet is formed on the upper surface of the body frame where the radiator and oil cooler are located to allow air to be introduced for cooling the radiator and oil cooler.

[0015] In some examples, optionally including at least one preferred example, the first inlet may be a small electric excavator, characterized in that it includes a long hole extending horizontally and an inclined hole extending downwardly from one end of the long hole.

[0016] In some examples, optionally including at least one preferred example, the fourth inlet may be formed in an inclined shape with an open rear side on the upper surface of the body frame, which may be a small electric excavator.

[0017] According to the small electric excavator according to the present disclosure, a radiator and an oil cooler are arranged immediately behind a cooling fan, and the cooling fan is configured to blow the internal air of the body frame forward, so that the air heated while passing through the radiator can be discharged to the outside without affecting the battery.

[0018] According to the small electric excavator according to the present disclosure, a blocking wall is installed inside the body frame to at least partially block the inflow of air from the left to the right with respect to the center line, thereby blocking the air that has become hot while passing through the MCV located at the left front inside the body frame from moving to the radiator and oil cooler located at the right front, thereby preventing the cooling efficiency of the radiator and oil cooler from being reduced.

[0019] According to the small electric excavator according to the present disclosure, the first to fourth inlets through which cold air is introduced into the body frame and the outlets through which hot air is discharged are efficiently arranged, thereby improving the cooling efficiency of components arranged inside the body frame.

[0020] The effects of the present disclosure are not limited to the effects described above, but should be understood to include all effects that can be inferred from the detailed description of the present disclosure or the composition of the disclosure described in the claims.

[0021] The disclosed aspects, embodiments (including any preferred embodiments), and / or accompanying claims may be suitably combined with one another as would be apparent to one skilled in the art.

[0022] Additional features and advantages are set forth in the following description, claims and drawings, and in part will be readily apparent to those skilled in the art or may be recognized by practicing the teachings herein.

[0023] The example is described in more detail below with reference to the attached drawings.

[0024] FIG. 1 is a drawing showing the basic configuration of a small electric excavator according to one aspect of the present disclosure.

[0025] Figure 2 is a front perspective view of the upper swivel body according to one aspect of the present disclosure.

[0026] Figure 3 is a rear perspective view of the upper swivel body according to one side of the present disclosure.

[0027] Figure 4 is a plan view of the upper swivel body according to one side of the present disclosure.

[0028] Fig. 5 is a drawing partially showing the internal space of the upper swivel body according to one side of the present disclosure.

[0029] Fig. 6 is a cross-sectional view taken along line AA' of Fig. 2, schematically showing the air flow inside the body frame according to one side of the present disclosure.

[0030] Fig. 7 is a cross-sectional view taken along line BB' of Fig. 3, schematically showing the air flow inside the body frame according to one side of the present disclosure.

[0031] Figure 8 is a rear perspective view of the upper swivel body according to another aspect of the present disclosure.

[0032] The detailed description set forth below provides information and examples of the disclosed technology with sufficient detail to enable those skilled in the art to practice the present disclosure. However, the present disclosure may be implemented in many different forms and is therefore not limited to the aspects described herein. In addition, for the purpose of clearly illustrating the present disclosure, parts irrelevant to the description are omitted in the drawings, and like reference numerals are used throughout the specification to designate like parts.

[0033] The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting of the present disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. The terms "comprises," "comprising," as used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0034] While terms such as "first" and "second" may be used herein to describe various elements, it is to be understood that these elements should not be limited by these terms. These terms are used solely to distinguish one element from another. For example, without departing from the scope of the present disclosure, a first element could be referred to as a "second element," and similarly, a second element could also be referred to as a "first element."

[0035] Relative terms such as "below" or "above" or "upper" or "lower" or "horizontal" or "vertical" may be used herein to describe one element's relationship to another, as illustrated in the drawings. It will be understood that these terms and the terms discussed above are intended to encompass different orientations of the device in addition to the orientations depicted in the drawings. When a component is referred to as being "connected" or "coupled" to another component, it will be understood that it may be directly connected or coupled to the other component, or that intervening components may be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, no intervening elements are present.

[0036] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should be further understood that terms used herein should be interpreted to have a meaning consistent with their meaning within the context of this specification and related technologies, and will not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0037] Hereinafter, one aspect of the present disclosure will be described in detail with reference to the attached drawings.

[0038] FIG. 1 is a drawing showing the basic configuration of a small electric excavator according to one aspect of the present disclosure, FIG. 2 is a front perspective view of an upper slewing body according to one aspect of the present disclosure, FIG. 3 is a rear perspective view of an upper slewing body according to one aspect of the present disclosure, FIG. 4 is a plan view of an upper slewing body according to one aspect of the present disclosure, and FIG. 5 is a drawing partially showing an internal space of an upper slewing body according to one aspect of the present disclosure.

[0039] As illustrated in FIGS. 1 to 5, a small electric excavator (1000) according to one aspect of the present disclosure comprises a lower body (10), an upper slewing body (20) rotatably supported on the lower body (10), and a boom (31), an arm (32), and an attachment (33) operated by respective cylinders, and a working device (30) supported on the upper slewing body (20).

[0040] The lower drive body (10) is configured to support the load of the upper slewing body (20) and the work device (30) and move the small electric excavator (1000) forward and backward or left and right for work purposes.

[0041] The upper swing body (20) is a structure supported on the lower driving body (10) and is designed to rotate on the lower driving body (10) by a swing device including a swing motor, a swing reduction gear, etc.

[0042] The work device (30) is installed to be supported by the upper slewing body (20) and is configured to perform the work of a small electric excavator (1000). At this time, the work may refer to various tasks at civil engineering and construction sites. The work device (30) may be configured to include a boom (31), an arm (32), and an attachment (33) each operated by a cylinder, and is installed while being supported toward the front of the upper slewing body (20). Therefore, when the upper slewing body (20) rotates, the work device (30) rotates together with the upper slewing body (20).

[0043] Meanwhile, the upper swing body (20) includes a body frame (100), a cabin (200), and a counterweight (300).

[0044] More specifically, the upper swing body (20) is configured to include a body frame (100), a cabin (200) installed on the left side of the body frame (100), and a counterweight (300) installed on the rear side of the body frame (100).

[0045] The body frame (100) is rotatably installed on the lower driving body (10) by a swivel device. That is, the body frame (100) forms a supporting structure and constitutes the base of the upper swivel body (20).

[0046] The body frame (100) is a supporting structure surrounded by a front portion (100a), a rear portion (100b), a left side portion (100c), a right side portion (100d), an upper portion (100e), and a lower portion (100f). At this time, the rear portion (100b) of the body frame (100) may be in the form of a rear cover. A counterweight (300) is installed at the rear of the body frame, i.e., on the lower side of the rear portion (100b). In addition, a cabin (200) may be installed on the body frame (100), and the cabin (200) may preferably be installed on the left side of the centerline (CL) on the body frame (100). An internal space capable of accommodating components is formed inside the body frame (100).

[0047] The cabin (200) may be provided with a driver's seat for the operator to sit in. In front of the driver's seat, various handles or pedals for operating or driving the small electric excavator (1000) may be provided.

[0048] A counter weight (300) is installed at the rear of the body frame (100). This counter weight (300) is intended to balance the weight with the work device (30) and may be formed of a weight having a rearward convex shape.

[0049] FIG. 6 is a cross-sectional view taken along line AA' of FIG. 2, schematically showing air flow inside a body frame according to one side of the present disclosure, and FIG. 7 is a cross-sectional view taken along line BB' of FIG. 3, schematically showing air flow inside a body frame according to one side of the present disclosure.

[0050] Referring to FIGS. 2 to 7, the small electric excavator (1000) of the present disclosure may include components such as a cooling fan (110), a radiator (120), an oil cooler (130), a main control valve (MCV) (140), an air conditioning system (HAVC) (150), a hydraulic tank (160), an electric motor (170), a hydraulic pump (180), a battery (ESS) (190), and other electric devices. In addition, the other electric devices may include a converter, an inverter, a junction box, a motor drive, and the like. These components of the small electric excavator (1000) may be provided in the internal space of the upper swivel body (20), more specifically, the body frame (100).

[0051] Meanwhile, the compact electric excavator (1000) has a narrow interior space, which does not provide sufficient space to accommodate various components. Therefore, it is important to efficiently arrange each component. In particular, considering the location of the battery (190), it is desirable to form an airflow in a direction that does not affect battery cooling. Furthermore, since components such as the MCV (140), hydraulic tank (160), and hydraulic pump (180) that use hydraulic oil are the largest heat sources in the compact electric excavator (1000), it is important to efficiently manage the heat of these components.

[0052] Referring to FIGS. 6 and 7, inside the body frame (100), an MCV (140), an HVAC (150), and a hydraulic tank may be arranged on the left side based on the center line (CL), and a cooling fan (110), a radiator (120), an oil cooler (130), a battery (190), an electric motor (170), a hydraulic pump (180), and other electrical devices may be arranged on the right side.

[0053] In addition, one or more inlets (102, 103, 104, 105) through which cold air flows in may be formed in the body frame (100), and an outlet (106) through which air heated while passing through internal components flows out may be formed in the front part (100a) of the body frame (100) based on the center line (CL).

[0054] At this time, the cooling fan (110) is for cooling the heat generated from the components constituting the small electric excavator (1000) with air, and can be placed right behind the outlet (106). This cooling fan (110) blows the internal air of the body frame (100) to force it to flow forward, thereby causing the internal air to flow out to the outside through the outlet (106).

[0055] Meanwhile, the radiator (120) and oil cooler (130) constituting the heat exchanger may be placed immediately behind the cooling fan (110). The radiator (120) is an element for releasing heat of cooling water for an electric device such as an electric motor (170), and the oil cooler (130) is an element for cooling hydraulic oil returning to the hydraulic tank (160) from a hydraulic device such as a work device (30).

[0056] These radiators (120) and oil coolers (130) can be arranged in a row laterally behind the cooling fan (110) and can be positioned downstream in the flow of cooling air by the cooling fan (110). That is, since the radiator (120) and oil cooler (130) are arranged immediately behind the cooling fan (110) and the cooling fan (110) is configured to blow the internal air of the body frame (100) forward, the air heated while passing through the radiator (120) can be discharged to the outside without affecting the battery (190).

[0057] The MCV (140) is for controlling the direction of hydraulic oil discharged from the hydraulic pump (180) to operate the work device (30), and may be placed on the left front side and the lower part of the cabin (200) based on the centerline (CL) inside the body frame (100). A ventilation (101) may be formed on the lower part (100f) of the body frame (100) where the MCV (140) is positioned so that heat generated from the MCV (140) can be circulated by natural convection. That is, the ventilation (101) may be positioned on the lower side of the MCV (140).

[0058] The temperature of the MCV (140) can rise to approximately 90° due to oil, and the air flowing in through the ventilation (101) can become hot as it passes through the MCV (140). In this way, if the air that becomes hot as it passes through the MCV (140) passes through the radiator (120) and the oil cooler (130), a problem may occur in which the cooling efficiency of the radiator (120) and the oil cooler (130) decreases.

[0059] Accordingly, as illustrated in FIGS. 5 and 6, a blocking wall (107) may be installed inside the body frame (100) to at least partially block the inflow of air from the left to the right based on the center line (CL). That is, the blocking wall (107) blocks the air heated while passing through the MCV (140) located at the left front inside the body frame (100) from moving to the radiator (120) and oil cooler (130) located at the right front, thereby preventing the cooling efficiency of the radiator (120) and oil cooler (130) from being reduced.

[0060] The hydraulic tank (160) is a hydraulic oil storage tank for supplying hydraulic oil to the hydraulic pump (180), and can be placed on the left rear side based on the center line (CL) inside the body frame (100).

[0061] A third inlet (104) may be formed on the lower surface (100f) of the body frame (100) where the hydraulic tank (160) is located to allow air to flow in for cooling the hydraulic tank (160). That is, the third inlet (104) may be located on the lower side of the hydraulic tank (160).

[0062] Referring to FIGS. 6 and 7, the electric motor (170), hydraulic pump (180), and electric devices can be placed on the right rear side with respect to the center line (CL) inside the body frame (100).

[0063] The electric motor (170) is configured to generate power to drive the small electric excavator (1000) using the electric energy of the battery (190), and the hydraulic pump (180) is configured to provide pressure to drive each component of the small electric excavator (1000) using the power generated from the electric motor (170). That is, the hydraulic pump (180) is driven by the power from the electric motor (170) and discharges a flow rate to drive the work device (30) and the lower travel body (10). For example, the hydraulic pump (180) provides pressure to the boom cylinder, the arm cylinder, and the attachment cylinder to drive the boom (31), the arm (32), and the attachment (33). At this time, the hydraulic pump (180) can receive hydraulic pressure from the hydraulic tank (160) and provide pressure to the work device (30).

[0064] The electrical devices may include a converter, an inverter, a junction box, a motor drive, etc. These electrical devices may be arranged on the right rear side with respect to the centerline (CL) inside the body frame (100), preferably above the electric motor (170) and the hydraulic pump (180). A converter is a device that changes the shape of a signal or energy. Such a converter may include a DC / DC converter that converts direct current of a certain voltage into direct current of a different voltage. An inverter is a device that converts direct current into alternating current. That is, the inverter converts direct current of the battery (190) into alternating current of a certain voltage required to drive the electric motor (170). The junction box controls the power transmitted to the battery (190) and controls the transmission of the power stored in the battery (190) to peripheral components. That is, the junction box controls the transmission of the power of the battery (190) to the converter, inverter, etc. The motor drive is an electronic control device that controls an electric motor (170) and can perform torque control, speed control, position control, etc. of the electric motor (170).

[0065] Meanwhile, referring to FIGS. 6 and 7, a first inlet (102) may be formed in the rear portion (100b) of the body frame (100) to allow air to flow in for cooling the electric motor (170), hydraulic pump (180), and electric devices arranged at the rear of the body frame (100). This first inlet (102) may include one or more long holes (102a) extending in a horizontal direction. The cold air introduced through the first inlet (102) may sequentially pass through the electric motor (170), hydraulic pump (180), electric devices, radiator (120), and oil cooler (130) arranged at the rear, and then be discharged to the outside through the cooling fan (110).

[0066] In this way, as the first inlet (102) is formed in the rear portion (100b) of the body frame (100), the electric motor (170), hydraulic pump (180), and electric devices located at the rear can be efficiently cooled.

[0067] Referring to FIGS. 6 and 7, the battery (190) may be placed in the right center relative to the centerline (CL) inside the body frame (100). More specifically, the battery (190) may be placed behind the radiator (120) and the oil cooler (130), and in front of the electric motor (170) and the hydraulic pump (180), and may be placed toward the right side (100d) of the body frame (100).

[0068] A second inlet (103) may be formed on the right side (100d) of the body frame (100) to allow air to be introduced for cooling the battery (190). The cold air introduced through the second inlet (103) may sequentially pass through the battery (190), radiator (120), and oil cooler (130) and then be discharged to the outside through the cooling fan (110).

[0069] Meanwhile, since the first inlet (102), second inlet (103), and third inlet (104) described above are far from the cooling fan (110) positioned at the front, cold air introduced through the first inlet (102), second inlet (103), and third inlet (104) passes through several parts before reaching the radiator (120) and oil cooler (130), and thus the cooling efficiency of the radiator (120) and oil cooler (130) may not be good.

[0070] That is, referring to FIGS. 3 to 5 and FIG. 7, in order to increase the cooling efficiency of the radiator (120) and oil cooler (130) positioned at the rear of the cooling fan (110), a fourth inlet (105) may be formed on the upper surface (100e) of the body frame (100) where the radiator (120) and oil cooler (130) are positioned so that air for cooling the radiator (120) and oil cooler (130) may be introduced.

[0071] Since the cold air flowing in through the fourth inlet (105) can directly affect the radiator (120) and oil cooler (130), the cooling efficiency of the radiator (120) and oil cooler (130) can be increased.

[0072] For example, the fourth inlet (105) may be formed in an inclined shape with the rear end open on the upper surface (100e) of the body frame (100). When the fourth inlet (105) is formed in an inclined shape with the rear end open, hot air blown forward by the cooling fan (110) and discharged through the outlet (106) formed in the front end (100a) can be prevented from entering the fourth inlet (105) again, thereby reducing cooling efficiency.

[0073] Figure 8 is a rear perspective view of the upper swivel body according to another aspect of the present disclosure.

[0074] Referring to FIGS. 7 and 8, the first inlet (102) may include one or more horizontal long holes (102a), and an inclined hole (102b) extending obliquely from one end of the long hole (102a). That is, in order to improve the cooling efficiency of the hydraulic tank (130) and the hydraulic pump (180) arranged at the rear inside the body frame (100), an inclined hole (102b) extending from the long hole (102a) may be further formed, and it is preferable that the inclined hole (102b) be formed to be inclined downward in order to increase the amount of air introduced into the hydraulic tank (130) and the hydraulic pump (180).

[0075] In this way, the small electric excavator of the present disclosure can efficiently manage the heat generation of hydraulic devices such as the MCV, hydraulic tank, and hydraulic pump that use hydraulic oil, which is the largest heat source, while simultaneously arranging internal components and various cooling devices (cooling fan, radiator, oil cooler, inlet, outlet) so as not to affect the cooling of the battery, thereby improving the overall cooling efficiency of the small electric excavator.

[0076] It should be understood that the present disclosure is not limited to the embodiments described above and illustrated in the drawings. Rather, those skilled in the art will recognize that numerous modifications and variations can be made within the scope of the present disclosure and the appended claims. In the drawings and specification, aspects are disclosed for illustrative purposes only, not for purposes of limitation, and the scope of the present disclosure is set forth in the claims below.

[0077]

[0078] Description of the symbol

[0079] 1000 compact electric excavator

[0080] 10 Lower body

[0081] 20 upper swivel

[0082] 30 working devices

[0083] 31 Boom

[0084] 32 Aam

[0085] 33 Attachment

[0086] 100 body frame

[0087] 100a front

[0088] 100b rear

[0089] 100c left side

[0090] 100d right side

[0091] 100e top surface

[0092] 100f lower part

[0093] 101 Ventilation

[0094] 102 First Inlet

[0095] 103 Second Inlet

[0096] 104 Third Inlet

[0097] 105 4th Inlet

[0098] 106 Outlet

[0099] 107 barrier

[0100] 110 cooling fan

[0101] 120 radiator

[0102] 130 oil cooler

[0103] 140 MCV

[0104] 150 HAVC

[0105] 160 hydraulic tank

[0106] 170 electric motor

[0107] 180 hydraulic pump

[0108] 190 battery

[0109] 200 cabins

[0110] 300 counterweight

[0111] CL centerline

Claims

1. A small electric excavator including a lower drive body, an upper swing body and a working device, The upper swing body includes a body frame, a cabin installed on the left side of the body frame, and a counterweight installed on the rear of the body frame. Inside the above body frame, the MCV and hydraulic tank are placed on the left side of the center line, and the cooling fan, radiator, oil cooler, battery, electric motor, hydraulic pump, and electrical devices are placed on the right side. The body frame is provided with one or more inlets through which cold air flows in, and an outlet through which heated air flows out is provided at the front of the body frame. A small electric excavator, wherein the cooling fan is positioned immediately behind the outlet and configured to blow the internal air of the body frame forward.

2. In paragraph 1, A compact electric excavator, characterized in that the radiator and the oil cooler are positioned immediately behind the cooling fan.

3. In paragraph 2, A small electric excavator characterized in that the MCV is positioned on the left front side based on the centerline inside the body frame, and ventilation is formed on the lower part of the body frame where the MCV is positioned so that heat generated from the MCV can circulate.

4. In paragraph 3, A small electric excavator, characterized in that a blocking wall is installed inside the body frame to at least partially block the inflow of air from the left to the right based on the center line.

5. In paragraph 2, A small electric excavator characterized in that the hydraulic tank is positioned at the left rear side based on the center line inside the body frame, and a third inlet is formed on the lower part of the body frame where the hydraulic tank is located to allow air to flow in for cooling the hydraulic tank.

6. In paragraph 2, A small electric excavator characterized in that the electric motor, hydraulic pump and electric devices are arranged on the right rear side based on the center line inside the body frame, and a first inlet is formed at the rear of the body frame to allow air to flow in for cooling the electric motor, hydraulic pump and electric devices.

7. In paragraph 2, A compact electric excavator characterized in that the battery is placed behind the radiator and the oil cooler, and a second inlet is formed on the right side of the body frame to allow air to flow in for cooling the battery.

8. In paragraph 2, A small electric excavator, characterized in that a fourth inlet is formed on the upper surface of the body frame where the radiator and oil cooler are located to allow air to flow in for cooling the radiator and oil cooler.

9. In paragraph 6, The above first inlet is, A small electric excavator characterized by comprising a long hole extending horizontally and an inclined hole extending downwardly from one end of the long hole.

10. In paragraph 8, A small electric excavator, characterized in that the fourth inlet is formed in an inclined shape with an open rear end on the upper surface of the body frame.

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