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

[Technical Field]

[0001] The present disclosure relates generally to a small electric excavator. In particular aspects, the disclosure relates to a small electric excavator having a structure and arrangement capable of improving cooling efficiency of internal components. The disclosure can be applied to heavy-duty vehicles, such as trucks, buses, and construction equipment, among other vehicle types. Although the disclosure may be described with respect to a particular vehicle, the disclosure is not restricted to any particular vehicle.[Background Art]

[0002] An excavator is a type of construction machine that performs various tasks, such as a drilling task for digging into the ground, a loading task for transporting soil, an excavating task for creating a foundation, a crushing task for dismantling a building, a preparing task for preparing the ground, and a leveling task for leveling the ground, at a construction site. Such a construction machine may generally include a lower traveling body that serves to move the equipment, an upper slewing body that is slewably mounted on the lower traveling body, and a working device that is mounted on a front of the upper slewing body.

[0003] The conventional excavators usually have an engine, such as a diesel engine, mounted therein to obtain power for traveling, drive a hydraulic pump using the force of the engine, and supply a hydraulic oil discharged from the hydraulic pump to a hydraulic actuator such as a hydraulic motor or a hydraulic cylinder, thereby rotating a traveling crawler or a tire or operating a working device such as a boom, an arm, or a bucket.

[0004] The conventional excavators having an engine, such as a diesel engine, mounted therein as above has a disadvantage that operation costs increase due to an expensive fuel cost and a large amount of consumed fuel. In addition, regarding construction machines, there is continuing demand for tightened emission regulations, low-noise equipment, low maintenance costs, etc.

[0005] Accordingly, eco-friendly small electric excavators with relatively high efficiency have emerged in order to improve energy efficiency, workability, etc. However, such small electric excavators have a narrow inner space and thus have an insufficient space for accommodating components. Therefore, it is important to efficiently arrange each component. For example, preferably, a cooling device may be arranged in a direction not affecting battery cooling, in consideration of the position of a battery module. In addition, because various electric devices (motor, inverter, converter, various electronic control units (ECUs), etc.) other than a battery should all be arranged within a frame of a small electric excavator, there is also a need to manage heat generation of each component. While an engine is the largest heat source in existing excavators, various devices using a hydraulic oil (a hydraulic tank, a main control valve (MCV), a hydraulic pump, etc.) are the largest heat sources in electric excavators. Therefore, for efficient heat management of each component arranged in a small electric excavator, how an inlet portion through which cold air is introduced and an outlet portion through which air, which has become hot while passing through each component and a radiator, is discharged are arranged is important.[Disclosure][Technical Problem]

[0006] The present disclosure is for addressing the above-described problems of the related art and is directed to providing a small electric excavator having a structure and arrangement capable of improving cooling efficiency of internal components.[Technical Solution]

[0007] A first aspect of the disclosure provides a small electric excavator including a lower traveling body, an upper slewing body, and a working device, wherein the upper slewing body includes a body frame, a cabin installed on a left side on the body frame, and a counterweight installed on a rear side of the body frame, inside the body frame, with respect to a center line, a main control valve (MCV) and a hydraulic tank are disposed at a left side, and a cooling fan, a radiator, an oil cooler, a battery, an electric motor, a hydraulic pump, and electric devices are disposed at a right side, one or more inlets through which cold air is introduced are formed in the body frame, an outlet through which hot air is discharged is formed in a front surface portion of the body frame, and the cooling fan is disposed right behind the outlet and configured to blow air inside the body frame forward.

[0008] In some examples, including in at least one preferred example, optionally, the radiator and the oil cooler may be disposed right behind the cooling fan.

[0009] In some examples, including in at least one preferred example, optionally, the MCV may be disposed on a front on the left side with respect to the center line inside the body frame, and a ventilation may be formed in a lower surface portion of the body frame, where the MCV is located, to allow heat generated from the MCV to circulate.

[0010] In some examples, including in at least one preferred example, optionally, a blocking wall for at least partially blocking introduction of air from the left side to the right side with respect to the center line may be installed inside the body frame.

[0011] In some examples, including in at least one preferred example, optionally, the hydraulic tank may be disposed on a rear on the left side with respect to the center line inside the body frame, and a third inlet may be formed in the lower surface portion of the body frame, where the hydraulic tank is located, to allow air for cooling the hydraulic tank to be introduced.

[0012] In some examples, including in at least one preferred example, optionally, the electric motor, the hydraulic pump, and the electric devices may be disposed on a rear on the right side with respect to the center line inside the body frame, and a first inlet may be formed in a rear surface portion of the body frame to allow air for cooling the electric motor, the hydraulic pump, and the electric devices to be introduced.

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

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

[0015] In some examples, including in at least one preferred example, optionally, the first inlet may include a long hole extending in a horizontal direction and an inclined hole extending to be inclined downward from one end of the long hole.

[0016] In some examples, including in at least one preferred example, optionally, the fourth inlet may be formed in a form that is inclined and has an open rear in the upper surface portion of the body frame.

[0017] With a small electric excavator according to the disclosure, because a radiator and an oil cooler are disposed right behind a cooling fan, and the cooling fan is configured to blow air inside a body frame forward, air that has become hot while passing through the radiator can be discharged to the outside without affecting a battery.

[0018] With a small electric excavator according to the disclosure, because a blocking wall for at least partially blocking introduction of air from a left side to a right side with respect to a center line is installed inside a body frame, air, which has become hot while passing through a MCV located at a front left side inside the body frame, is blocked from moving to a radiator and an oil cooler that are located at a front right side, and a decrease in cooling efficiency of the radiator and the oil cooler can be prevented.

[0019] With a small electric excavator according to the disclosure, by efficiently arranging first to fourth inlets through which cold air is introduced and an outlet through which hot air is discharged in a body frame, cooling efficiency of components disposed inside the body frame can be improved.

[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, examples (including any preferred examples), and / or accompanying claims may be suitably combined with each other as would be apparent to anyone of ordinary skill in the art.

[0022] Additional features and advantages are disclosed in the following description, claims, and drawings, and in part will be readily apparent therefrom to those skilled in the art or recognized by practicing the disclosure as described herein.[Description of Drawings]

[0023] Examples are described in more detail below with reference to the appended drawings. FIG. 1 is a view illustrating a 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 the upper slewing body according to one aspect of the present disclosure. FIG. 4 is a top view of the upper slewing body according to one aspect of the present disclosure. FIG. 5 is a view partially showing an inner space of the upper slewing body according to one aspect of the present disclosure. FIG. 6 is a cross-sectional view along line A-A' of FIG. 2 and schematically shows an air flow inside a body frame according to one aspect of the present disclosure. FIG. 7 is a cross-sectional view along line B-B' of FIG. 3 and schematically shows an air flow inside the body frame according to one aspect of the present disclosure. FIG. 8 is a rear perspective view of an upper slewing body according to another aspect of the present disclosure. [Modes of the Invention]

[0024] 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 disclosure. However, the present disclosure may be implemented in various different forms and thus is not limited to aspects described herein. In addition, parts irrelevant to the description are omitted from the drawings to clearly describe the present disclosure, and like parts are denoted by like reference numerals throughout.

[0025] The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms "comprises," "comprising," "includes," and / or "including" when 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.

[0026] It will be understood that, although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element without departing from the scope of the present disclosure.

[0027] Relative terms such as "below" or "above" or "upper" or "lower" or "horizontal" or "vertical" may be used herein to describe a relationship of one element to another element as illustrated in the Figures. It will be understood that these terms and those discussed above are intended to encompass different orientations of the device in addition to the orientation depicted in the Figures. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or intervening elements may be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements present.

[0028] 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 belongs. It will be further understood that terms used herein should be interpreted as having a meaning consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0029] Hereinafter, one aspect of the present disclosure will be described in detail with reference to the attached drawings.

[0030] FIG. 1 is a view illustrating a 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 the upper slewing body according to one aspect of the present disclosure, FIG. 4 is a top view of the upper slewing body according to one aspect of the present disclosure, and FIG. 5 is a view partially showing an inner space of the upper slewing body according to one aspect of the present disclosure.

[0031] As illustrated in FIGS. 1 to 5, a small electric excavator 1000 according to one aspect of the present disclosure is configured to include a lower traveling body 10, an upper slewing body 20 that is rotatably supported on the lower traveling body 10, and a working device 30 that includes a boom 31, an arm 32, and an attachment 33, each operating by a cylinder thereof, and is supported by the upper slewing body 20.

[0032] The lower traveling body 10 is a configuration that moves the small electric excavator 1000 in a front-rear direction or a left-right direction for a working purpose while supporting loads of the upper slewing body 20 and the working device 30.

[0033] The upper slewing body 20 is a configuration that is supported on the lower traveling body 10 and is designed to rotate on the lower traveling body 10 by a slewing device including a swing motor, a swing reduction gear, etc.

[0034] The working device 30 is a configuration that is installed to be supported by the upper slewing body 20 to perform work of the small electric excavator 1000. Here, work may refer to various tasks in civil engineering and construction sites. The working device 30 may be configured to include the boom 31, the arm 32, the attachment 33 each operating by the cylinder thereof, and is installed to be supported toward the front of the upper slewing body 20. Accordingly, when the upper slewing body 20 rotates, the working device 30 rotates together with the upper slewing body 20.

[0035] Meanwhile, the upper slewing body 20 includes a body frame 100, a cabin 200, and a counterweight 300.

[0036] More specifically, the upper slewing body 20 is configured to include the body frame 100, the cabin 200 installed on a right side on the body frame 100, and the counterweight 300 installed on a rear side of the body frame 100.

[0037] The body frame 100 is installed to be slewable on the lower traveling body 10 by the slewing device. That is, the body frame 100 forms a support structure and constitutes a base of the upper slewing body 20.

[0038] The body frame 100 is a support structure surrounded by a front surface portion 100a, a rear surface portion 100b, a left side surface portion 100c, a right side surface portion 100d, an upper surface portion 100e, and a lower surface portion 100f. Here, the rear surface portion 100b of the body frame 100 may be in the form of a rear cover. The counterweight 300 is installed on the rear of the body frame, that is, a lower side of the rear surface portion 100b. In addition, the cabin 200 may be installed on the body frame 100, and preferably, the cabin 200 may be installed at a left side with respect to a center line CL on the body frame 100. An inner space that can accommodate components is formed inside the body frame 100.

[0039] A driver's seat on which an operator can sit after entering the cabin 200 may be provided in the cabin 200. A handle, a pedal, or the like for manipulating working or traveling of the small electric excavator 1000 may be provided in various ways in front of the driver's seat.

[0040] The counterweight 300 is installed on a rear of the body frame 100. The counterweight 300 is for counterbalancing the weight of the working device 30 and may be formed of a heavy weight having a shape that is convex toward the rear.

[0041] FIG. 6 is a cross-sectional view along line A-A' of FIG. 2 and schematically shows an air flow inside a body frame according to one aspect of the present disclosure, and FIG. 7 is a cross-sectional view along line B-B' of FIG. 3 and schematically shows an air flow inside the body frame according to one aspect of the present disclosure.

[0042] 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, a heating, ventilation, and air conditioning (HVAC) system 150, a hydraulic tank 160, an electric motor 170, a hydraulic pump 180, a battery (an energy storage system (ESS)) 190, and other electric devices. In addition, other electric devices may include a converter, an inverter, a junction box, a motor drive, etc. Such components of the small electric excavator 1000 may be provided in the upper slewing body 20, more specifically, the inner space of the body frame 100.

[0043] Meanwhile, the small electric excavator 1000 has a narrow inner space and thus have an insufficient space for accommodating the components. Therefore, it is important to efficiently arrange each component. In particular, an air flow may be formed in a direction not affecting battery cooling, in consideration of the position of the battery 190. In addition, because components such as the MCV 140, the hydraulic tank 160, and the hydraulic pump 180 that use a hydraulic oil are the largest heat sources in the small electric excavator 1000, it is important to efficiently perform heat management of such components.

[0044] Referring to FIGS. 6 and 7, inside the body frame 100, with respect to the center line CL, the MCV 140, the HVAC system 150, and the hydraulic tank may be disposed at the left side, and the cooling fan 110, the radiator 120, the oil cooler 130, the battery 190, the electric motor 170, the hydraulic pump 180, and other electric devices may be disposed at the right side.

[0045] In addition, one or more inlets 102, 103, 104, and 105 through which cold air is introduced may be formed in the body frame 100, and an outlet 106 through which air, which has become hot while passing through the internal components, may be formed in the front surface portion 100a of the body frame 100 with respect to the center line CL.

[0046] Here, the cooling fan 110 is for cooling heat generated from the components constituting the small electric excavator 1000 using air, and may be disposed right behind the outlet 106. The cooling fan 110 blows air inside the body frame 100 and forcibly causes the air to flow forward so that the air inside the body frame 100 is discharged to the outside through the outlet 106.

[0047] Meanwhile, the radiator 120 and the oil cooler 130 that constitute a heat exchanger may be disposed right behind the cooling fan 110. The radiator 120 is an element for releasing heat of a coolant for an electric device such as the electric motor 170, and the oil cooler 130 is an element for cooling a hydraulic oil that returns to the hydraulic tank 160 from a hydraulic device such as the working device 30.

[0048] The radiator 120 and the oil cooler 130 may be disposed in a row in a side direction behind the cooling fan 110 and may be located at a downstream side of a flow of cooling air that is caused by the cooling fan 110. That is, because the radiator 120 and the oil cooler 130 are disposed right behind the cooling fan 110, and the cooling fan 110 is configured to blow air inside the body frame 100 forward, air, which has become hot while passing through the radiator 120, may be discharged to the outside without affecting the battery 190.

[0049] The MCV 140 is for controlling a direction of a hydraulic oil discharged from the hydraulic pump 180 to operate the working device 30, and may be disposed on a front on the left side with respect to the center line CL inside the body frame 100 and at a lower portion of the cabin 200. A ventilation 101 may be formed in the lower surface portion 100f of the body frame 100, where the MCV 140 is located, to allow heat generated from the MCV 140 to circulate by natural convection. That is, the ventilation 101 may be located at a lower side of the MCV 140.

[0050] A temperature of the MCV 140 may increases to about 90 °C due to oil, and air introduced through the ventilation 101 may become hot while passing through the MCV 140. In this way, when the air that has become hot while passing through the MCV 140 passes through the radiator 120 and the oil cooler 130, a problem in which cooling efficiency of the radiator 120 and the oil cooler 130 decreases may occur.

[0051] Accordingly, as illustrated in FIGS. 5 and 6, a blocking wall 107 for at least partially blocking introduction of air from the left side to the right side with respect to the center line CL may be installed inside the body frame 100. That is, the blocking wall 107 may block movement of air, which has become hot while passing through the MCV 140 located at the front left side inside the body frame 100, to the radiator 120 and the oil cooler 130 that are located at the front right side, thereby preventing a decrease in the cooling efficiency of the radiator 120 and the oil cooler 130.

[0052] The hydraulic tank 160 is a hydraulic oil reservoir for supplying a hydraulic oil to the hydraulic pump 180 and may be disposed on a rear on the left side with respect to the center line CL inside the body frame 100.

[0053] A third inlet 104 may be formed in the lower surface portion 100f of the body frame 100, where the hydraulic tank 160 is located, to allow air for cooling the hydraulic tank 160 to be introduced. That is, the third inlet 104 may be located at a lower side of the hydraulic tank 160.

[0054] Referring to FIGS. 6 and 7, the electric motor 170, the hydraulic pump 180, and electric devices may be disposed on a rear on the right side with respect to the center line CL inside the body frame 100.

[0055] The electric motor 170 is a configuration for producing power for driving the small electric excavator 1000 using electrical energy of the battery 190, and the hydraulic pump 180 is a configuration for providing pressure for driving each component of the small electric excavator 1000 using the power generated by the electric motor 170. That is, the hydraulic pump 180 operates by power of the electric motor 170 and drives the working device 30 and the lower traveling body 10 by discharging a flow. For example, the hydraulic pump 180 provides pressure to a boom cylinder, an arm cylinder, and an attachment cylinder to drive the boom 31, the arm 32, and the attachment 33. Here, the hydraulic pump 180 may receive a hydraulic pressure from the hydraulic tank 160 and provide pressure to the working device 30.

[0056] Electric devices may include a converter, an inverter, a junction box, a motor drive, etc. Such electric devices may be disposed on the rear on the right side with respect to the center line CL inside the body frame 100, preferably at an upper side of the electric motor 170 and the hydraulic pump 180. The converter is a device that changes the shape of a signal or energy. The converter may include a DC / DC converter that converts DC power of one voltage into DC power of another voltage. The inverter is a device that converts DC power into AC power. That is, the inverter converts DC power of the battery 190 into AC power of a predetermined voltage that is necessary for driving the electric motor 170. The junction box serves to control the power transferred to the battery 190 and control the power stored in the battery 190 to be transferred to peripheral components. That is, the junction box controls the power of the battery 190 to be transferred to the converter, the inverter, etc. The motor drive is an electronic control device that controls the electric motor 170 and may perform torque control, speed control, position control, etc., of the electric motor 170.

[0057] Meanwhile, referring to FIGS. 6 and 7, a first inlet 102 may be formed in the rear surface portion 100b of the body frame 100 to allow air for cooling the electric motor 170, the hydraulic pump 180, and electric devices, which are disposed at the rear inside the body frame 100, to be introduced. The first inlet 102 may include one or more long holes 102a that longitudinally extend in the horizontal direction. Cold air introduced through the first inlet 102 may be discharged to the outside through the cooling fan 110 after sequentially passing through the electric motor 170, the hydraulic pump 180, the electric devices, the radiator 120, and the oil cooler 130 that are disposed at the rear.

[0058] In this way, because the first inlet 102 is formed in the rear surface portion 100b of the body frame 100, the electric motor 170, the hydraulic pump 180, the electric devices that are disposed at the rear can be efficiently cooled.

[0059] Referring to FIGS. 6 and 7, the battery 190 may be disposed on a central portion on the right side with respect to the center line CL inside the body frame 100. More specifically, the battery 190 may be disposed 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 disposed to lean toward the right side surface portion 100d of the body frame 100.

[0060] A second inlet 103 may be formed in the right side surface portion 100d of the body frame 100 to allow air for cooling the battery 190 to be introduced. Cold air introduced through the second inlet 103 may be discharged to the outside through the cooling fan 110 after sequentially passing through the battery 190, the radiator 120, and the oil cooler 130.

[0061] Meanwhile, because a distance from each of the above-described first inlet 102, second inlet 103, and third inlet 104 to the cooling fan 110 disposed at the front is far, the cold air introduced through the first inlet 102, the second inlet 103, and the third inlet 104 reaches the radiator 120 and the oil cooler 130 after passing through several components, and accordingly, the cooling efficiency of the radiator 120 and the oil cooler 130 may not be high.

[0062] That is, referring to FIGS. 3 to 5 and FIG. 7, in order to increase the cooling efficiency of the radiator 120 and the oil cooler 130 that are disposed behind the cooling fan 110, a fourth inlet 105 may be formed in the upper surface portion 100e of the body frame 100, where the radiator 120 and the oil cooler 130 are located, to allow air for cooling the radiator 120 and the oil cooler 130 to be introduced.

[0063] Because cold air introduced through the fourth inlet 105 can directly affect the radiator 120 and the oil cooler 130, the cooling efficiency of the radiator 120 and the oil cooler 130 can be increased.

[0064] According to one example, the fourth inlet 105 may be formed in a form that is inclined and has an open rear in the upper surface portion 100e of the body frame 100. When the fourth inlet 105 is formed in the form that is inclined and has an open rear, hot air that is blown forward by the cooling fan 110 and discharged through the outlet 106 formed in the front surface portion 100a can be prevented from re-entering through the fourth inlet 105 and decreasing the cooling efficiency.

[0065] FIG. 8 is a rear perspective view of an upper slewing body according to another aspect of the present disclosure.

[0066] Referring to FIGS. 7 and 8, the first inlet 102 may include one or more long holes 102a extending in the horizontal direction and an inclined hole 102b extending to be inclined from one end of the long hole 102a. That is, the inclined hole 102b extending from the long hole 102a may be further formed to improve cooling efficiency of the hydraulic tank 130 and the hydraulic pump 180 that are disposed at the rear inside the body frame 100, and preferably, the inclined hole 102b may be formed to be inclined downward to increase the amount of air introduced into the hydraulic tank 130 and the hydraulic pump 180.

[0067] In this way, because internal components and various cooling devices (a cooling fan, a radiator, an oil cooler, an inlet, and an outlet) are disposed in a small electric excavator of the present disclosure to not affect battery cooling while efficiently managing heat generation of hydraulic devices such as a MCV, a hydraulic tank, and a hydraulic pump using a hydraulic oil, which are the largest heat sources, the overall cooling efficiency of the small electric excavator can be improved.

[0068] It should be understood that the present disclosure is not limited to the embodiments described above and illustrated in the drawings. Rather, those of ordinary skill in the art will recognize that many changes and modifications 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 and not for purposes of limitation, and the scope of the present disclosure is set forth in the claims below.Description of reference numerals

[0069] 1000 small electric excavator 10 lower traveling body 20 upper slewing body 30 working device 31 boom 32 arm 33 attachment 100 body frame 100a front surface portion 100b rear surface portion 100c left side surface portion 100d right side surface portion 100e upper surface portion 100f lower surface portion 101 ventilation 102 first inlet 103 second inlet 104 third inlet 105 fourth inlet 106 outlet 107 blocking wall 110 cooling fan 120 radiator 130 oil cooler 140 MCV 150 HVAC 160 hydraulic tank 170 electric motor 180 hydraulic pump 190 battery 200 cabin 300 counterweight CL center line

Examples

Embodiment Construction

[0024]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 disclosure. However, the present disclosure may be implemented in various different forms and thus is not limited to aspects described herein. In addition, parts irrelevant to the description are omitted from the drawings to clearly describe the present disclosure, and like parts are denoted by like reference numerals throughout.

[0025]The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms "comprises," "comprising...

[Technical Field]

[0001] The present disclosure relates generally to a small electric excavator. In particular aspects, the disclosure relates to a small electric excavator having a structure and arrangement capable of improving cooling efficiency of internal components. The disclosure can be applied to heavy-duty vehicles, such as trucks, buses, and construction equipment, among other vehicle types. Although the disclosure may be described with respect to a particular vehicle, the disclosure is not restricted to any particular vehicle.[Background Art]

[0002] An excavator is a type of construction machine that performs various tasks, such as a drilling task for digging into the ground, a loading task for transporting soil, an excavating task for creating a foundation, a crushing task for dismantling a building, a preparing task for preparing the ground, and a leveling task for leveling the ground, at a construction site. Such a construction machine may generally include a lower traveling body that serves to move the equipment, an upper slewing body that is slewably mounted on the lower traveling body, and a working device that is mounted on a front of the upper slewing body.

[0003] The conventional excavators usually have an engine, such as a diesel engine, mounted therein to obtain power for traveling, drive a hydraulic pump using the force of the engine, and supply a hydraulic oil discharged from the hydraulic pump to a hydraulic actuator such as a hydraulic motor or a hydraulic cylinder, thereby rotating a traveling crawler or a tire or operating a working device such as a boom, an arm, or a bucket.

[0004] The conventional excavators having an engine, such as a diesel engine, mounted therein as above has a disadvantage that operation costs increase due to an expensive fuel cost and a large amount of consumed fuel. In addition, regarding construction machines, there is continuing demand for tightened emission regulations, low-noise equipment, low maintenance costs, etc.

[0005] Accordingly, eco-friendly small electric excavators with relatively high efficiency have emerged in order to improve energy efficiency, workability, etc. However, such small electric excavators have a narrow inner space and thus have an insufficient space for accommodating components. Therefore, it is important to efficiently arrange each component. For example, preferably, a cooling device may be arranged in a direction not affecting battery cooling, in consideration of the position of a battery module. In addition, because various electric devices (motor, inverter, converter, various electronic control units (ECUs), etc.) other than a battery should all be arranged within a frame of a small electric excavator, there is also a need to manage heat generation of each component. While an engine is the largest heat source in existing excavators, various devices using a hydraulic oil (a hydraulic tank, a main control valve (MCV), a hydraulic pump, etc.) are the largest heat sources in electric excavators. Therefore, for efficient heat management of each component arranged in a small electric excavator, how an inlet portion through which cold air is introduced and an outlet portion through which air, which has become hot while passing through each component and a radiator, is discharged are arranged is important.[Disclosure][Technical Problem]

[0006] The present disclosure is for addressing the above-described problems of the related art and is directed to providing a small electric excavator having a structure and arrangement capable of improving cooling efficiency of internal components.[Technical Solution]

[0007] A first aspect of the disclosure provides a small electric excavator including a lower traveling body, an upper slewing body, and a working device, wherein the upper slewing body includes a body frame, a cabin installed on a left side on the body frame, and a counterweight installed on a rear side of the body frame, inside the body frame, with respect to a center line, a main control valve (MCV) and a hydraulic tank are disposed at a left side, and a cooling fan, a radiator, an oil cooler, a battery, an electric motor, a hydraulic pump, and electric devices are disposed at a right side, one or more inlets through which cold air is introduced are formed in the body frame, an outlet through which hot air is discharged is formed in a front surface portion of the body frame, and the cooling fan is disposed right behind the outlet and configured to blow air inside the body frame forward.

[0008] In some examples, including in at least one preferred example, optionally, the radiator and the oil cooler may be disposed right behind the cooling fan.

[0009] In some examples, including in at least one preferred example, optionally, the MCV may be disposed on a front on the left side with respect to the center line inside the body frame, and a ventilation may be formed in a lower surface portion of the body frame, where the MCV is located, to allow heat generated from the MCV to circulate.

[0010] In some examples, including in at least one preferred example, optionally, a blocking wall for at least partially blocking introduction of air from the left side to the right side with respect to the center line may be installed inside the body frame.

[0011] In some examples, including in at least one preferred example, optionally, the hydraulic tank may be disposed on a rear on the left side with respect to the center line inside the body frame, and a third inlet may be formed in the lower surface portion of the body frame, where the hydraulic tank is located, to allow air for cooling the hydraulic tank to be introduced.

[0012] In some examples, including in at least one preferred example, optionally, the electric motor, the hydraulic pump, and the electric devices may be disposed on a rear on the right side with respect to the center line inside the body frame, and a first inlet may be formed in a rear surface portion of the body frame to allow air for cooling the electric motor, the hydraulic pump, and the electric devices to be introduced.

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

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

[0015] In some examples, including in at least one preferred example, optionally, the first inlet may include a long hole extending in a horizontal direction and an inclined hole extending to be inclined downward from one end of the long hole.

[0016] In some examples, including in at least one preferred example, optionally, the fourth inlet may be formed in a form that is inclined and has an open rear in the upper surface portion of the body frame.

[0017] With a small electric excavator according to the disclosure, because a radiator and an oil cooler are disposed right behind a cooling fan, and the cooling fan is configured to blow air inside a body frame forward, air that has become hot while passing through the radiator can be discharged to the outside without affecting a battery.

[0018] With a small electric excavator according to the disclosure, because a blocking wall for at least partially blocking introduction of air from a left side to a right side with respect to a center line is installed inside a body frame, air, which has become hot while passing through a MCV located at a front left side inside the body frame, is blocked from moving to a radiator and an oil cooler that are located at a front right side, and a decrease in cooling efficiency of the radiator and the oil cooler can be prevented.

[0019] With a small electric excavator according to the disclosure, by efficiently arranging first to fourth inlets through which cold air is introduced and an outlet through which hot air is discharged in a body frame, cooling efficiency of components disposed inside the body frame can be improved.

[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, examples (including any preferred examples), and / or accompanying claims may be suitably combined with each other as would be apparent to anyone of ordinary skill in the art.

[0022] Additional features and advantages are disclosed in the following description, claims, and drawings, and in part will be readily apparent therefrom to those skilled in the art or recognized by practicing the disclosure as described herein.[Description of Drawings]

[0023] Examples are described in more detail below with reference to the appended drawings. FIG. 1 is a view illustrating a 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 the upper slewing body according to one aspect of the present disclosure. FIG. 4 is a top view of the upper slewing body according to one aspect of the present disclosure. FIG. 5 is a view partially showing an inner space of the upper slewing body according to one aspect of the present disclosure. FIG. 6 is a cross-sectional view along line A-A' of FIG. 2 and schematically shows an air flow inside a body frame according to one aspect of the present disclosure. FIG. 7 is a cross-sectional view along line B-B' of FIG. 3 and schematically shows an air flow inside the body frame according to one aspect of the present disclosure. FIG. 8 is a rear perspective view of an upper slewing body according to another aspect of the present disclosure. [Modes of the Invention]

[0024] 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 disclosure. However, the present disclosure may be implemented in various different forms and thus is not limited to aspects described herein. In addition, parts irrelevant to the description are omitted from the drawings to clearly describe the present disclosure, and like parts are denoted by like reference numerals throughout.

[0025] The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms "comprises," "comprising," "includes," and / or "including" when 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.

[0026] It will be understood that, although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element without departing from the scope of the present disclosure.

[0027] Relative terms such as "below" or "above" or "upper" or "lower" or "horizontal" or "vertical" may be used herein to describe a relationship of one element to another element as illustrated in the Figures. It will be understood that these terms and those discussed above are intended to encompass different orientations of the device in addition to the orientation depicted in the Figures. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or intervening elements may be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements present.

[0028] 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 belongs. It will be further understood that terms used herein should be interpreted as having a meaning consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0029] Hereinafter, one aspect of the present disclosure will be described in detail with reference to the attached drawings.

[0030] FIG. 1 is a view illustrating a 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 the upper slewing body according to one aspect of the present disclosure, FIG. 4 is a top view of the upper slewing body according to one aspect of the present disclosure, and FIG. 5 is a view partially showing an inner space of the upper slewing body according to one aspect of the present disclosure.

[0031] As illustrated in FIGS. 1 to 5, a small electric excavator 1000 according to one aspect of the present disclosure is configured to include a lower traveling body 10, an upper slewing body 20 that is rotatably supported on the lower traveling body 10, and a working device 30 that includes a boom 31, an arm 32, and an attachment 33, each operating by a cylinder thereof, and is supported by the upper slewing body 20.

[0032] The lower traveling body 10 is a configuration that moves the small electric excavator 1000 in a front-rear direction or a left-right direction for a working purpose while supporting loads of the upper slewing body 20 and the working device 30.

[0033] The upper slewing body 20 is a configuration that is supported on the lower traveling body 10 and is designed to rotate on the lower traveling body 10 by a slewing device including a swing motor, a swing reduction gear, etc.

[0034] The working device 30 is a configuration that is installed to be supported by the upper slewing body 20 to perform work of the small electric excavator 1000. Here, work may refer to various tasks in civil engineering and construction sites. The working device 30 may be configured to include the boom 31, the arm 32, the attachment 33 each operating by the cylinder thereof, and is installed to be supported toward the front of the upper slewing body 20. Accordingly, when the upper slewing body 20 rotates, the working device 30 rotates together with the upper slewing body 20.

[0035] Meanwhile, the upper slewing body 20 includes a body frame 100, a cabin 200, and a counterweight 300.

[0036] More specifically, the upper slewing body 20 is configured to include the body frame 100, the cabin 200 installed on a right side on the body frame 100, and the counterweight 300 installed on a rear side of the body frame 100.

[0037] The body frame 100 is installed to be slewable on the lower traveling body 10 by the slewing device. That is, the body frame 100 forms a support structure and constitutes a base of the upper slewing body 20.

[0038] The body frame 100 is a support structure surrounded by a front surface portion 100a, a rear surface portion 100b, a left side surface portion 100c, a right side surface portion 100d, an upper surface portion 100e, and a lower surface portion 100f. Here, the rear surface portion 100b of the body frame 100 may be in the form of a rear cover. The counterweight 300 is installed on the rear of the body frame, that is, a lower side of the rear surface portion 100b. In addition, the cabin 200 may be installed on the body frame 100, and preferably, the cabin 200 may be installed at a left side with respect to a center line CL on the body frame 100. An inner space that can accommodate components is formed inside the body frame 100.

[0039] A driver's seat on which an operator can sit after entering the cabin 200 may be provided in the cabin 200. A handle, a pedal, or the like for manipulating working or traveling of the small electric excavator 1000 may be provided in various ways in front of the driver's seat.

[0040] The counterweight 300 is installed on a rear of the body frame 100. The counterweight 300 is for counterbalancing the weight of the working device 30 and may be formed of a heavy weight having a shape that is convex toward the rear.

[0041] FIG. 6 is a cross-sectional view along line A-A' of FIG. 2 and schematically shows an air flow inside a body frame according to one aspect of the present disclosure, and FIG. 7 is a cross-sectional view along line B-B' of FIG. 3 and schematically shows an air flow inside the body frame according to one aspect of the present disclosure.

[0042] 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, a heating, ventilation, and air conditioning (HVAC) system 150, a hydraulic tank 160, an electric motor 170, a hydraulic pump 180, a battery (an energy storage system (ESS)) 190, and other electric devices. In addition, other electric devices may include a converter, an inverter, a junction box, a motor drive, etc. Such components of the small electric excavator 1000 may be provided in the upper slewing body 20, more specifically, the inner space of the body frame 100.

[0043] Meanwhile, the small electric excavator 1000 has a narrow inner space and thus have an insufficient space for accommodating the components. Therefore, it is important to efficiently arrange each component. In particular, an air flow may be formed in a direction not affecting battery cooling, in consideration of the position of the battery 190. In addition, because components such as the MCV 140, the hydraulic tank 160, and the hydraulic pump 180 that use a hydraulic oil are the largest heat sources in the small electric excavator 1000, it is important to efficiently perform heat management of such components.

[0044] Referring to FIGS. 6 and 7, inside the body frame 100, with respect to the center line CL, the MCV 140, the HVAC system 150, and the hydraulic tank may be disposed at the left side, and the cooling fan 110, the radiator 120, the oil cooler 130, the battery 190, the electric motor 170, the hydraulic pump 180, and other electric devices may be disposed at the right side.

[0045] In addition, one or more inlets 102, 103, 104, and 105 through which cold air is introduced may be formed in the body frame 100, and an outlet 106 through which air, which has become hot while passing through the internal components, may be formed in the front surface portion 100a of the body frame 100 with respect to the center line CL.

[0046] Here, the cooling fan 110 is for cooling heat generated from the components constituting the small electric excavator 1000 using air, and may be disposed right behind the outlet 106. The cooling fan 110 blows air inside the body frame 100 and forcibly causes the air to flow forward so that the air inside the body frame 100 is discharged to the outside through the outlet 106.

[0047] Meanwhile, the radiator 120 and the oil cooler 130 that constitute a heat exchanger may be disposed right behind the cooling fan 110. The radiator 120 is an element for releasing heat of a coolant for an electric device such as the electric motor 170, and the oil cooler 130 is an element for cooling a hydraulic oil that returns to the hydraulic tank 160 from a hydraulic device such as the working device 30.

[0048] The radiator 120 and the oil cooler 130 may be disposed in a row in a side direction behind the cooling fan 110 and may be located at a downstream side of a flow of cooling air that is caused by the cooling fan 110. That is, because the radiator 120 and the oil cooler 130 are disposed right behind the cooling fan 110, and the cooling fan 110 is configured to blow air inside the body frame 100 forward, air, which has become hot while passing through the radiator 120, may be discharged to the outside without affecting the battery 190.

[0049] The MCV 140 is for controlling a direction of a hydraulic oil discharged from the hydraulic pump 180 to operate the working device 30, and may be disposed on a front on the left side with respect to the center line CL inside the body frame 100 and at a lower portion of the cabin 200. A ventilation 101 may be formed in the lower surface portion 100f of the body frame 100, where the MCV 140 is located, to allow heat generated from the MCV 140 to circulate by natural convection. That is, the ventilation 101 may be located at a lower side of the MCV 140.

[0050] A temperature of the MCV 140 may increases to about 90 °C due to oil, and air introduced through the ventilation 101 may become hot while passing through the MCV 140. In this way, when the air that has become hot while passing through the MCV 140 passes through the radiator 120 and the oil cooler 130, a problem in which cooling efficiency of the radiator 120 and the oil cooler 130 decreases may occur.

[0051] Accordingly, as illustrated in FIGS. 5 and 6, a blocking wall 107 for at least partially blocking introduction of air from the left side to the right side with respect to the center line CL may be installed inside the body frame 100. That is, the blocking wall 107 may block movement of air, which has become hot while passing through the MCV 140 located at the front left side inside the body frame 100, to the radiator 120 and the oil cooler 130 that are located at the front right side, thereby preventing a decrease in the cooling efficiency of the radiator 120 and the oil cooler 130.

[0052] The hydraulic tank 160 is a hydraulic oil reservoir for supplying a hydraulic oil to the hydraulic pump 180 and may be disposed on a rear on the left side with respect to the center line CL inside the body frame 100.

[0053] A third inlet 104 may be formed in the lower surface portion 100f of the body frame 100, where the hydraulic tank 160 is located, to allow air for cooling the hydraulic tank 160 to be introduced. That is, the third inlet 104 may be located at a lower side of the hydraulic tank 160.

[0054] Referring to FIGS. 6 and 7, the electric motor 170, the hydraulic pump 180, and electric devices may be disposed on a rear on the right side with respect to the center line CL inside the body frame 100.

[0055] The electric motor 170 is a configuration for producing power for driving the small electric excavator 1000 using electrical energy of the battery 190, and the hydraulic pump 180 is a configuration for providing pressure for driving each component of the small electric excavator 1000 using the power generated by the electric motor 170. That is, the hydraulic pump 180 operates by power of the electric motor 170 and drives the working device 30 and the lower traveling body 10 by discharging a flow. For example, the hydraulic pump 180 provides pressure to a boom cylinder, an arm cylinder, and an attachment cylinder to drive the boom 31, the arm 32, and the attachment 33. Here, the hydraulic pump 180 may receive a hydraulic pressure from the hydraulic tank 160 and provide pressure to the working device 30.

[0056] Electric devices may include a converter, an inverter, a junction box, a motor drive, etc. Such electric devices may be disposed on the rear on the right side with respect to the center line CL inside the body frame 100, preferably at an upper side of the electric motor 170 and the hydraulic pump 180. The converter is a device that changes the shape of a signal or energy. The converter may include a DC / DC converter that converts DC power of one voltage into DC power of another voltage. The inverter is a device that converts DC power into AC power. That is, the inverter converts DC power of the battery 190 into AC power of a predetermined voltage that is necessary for driving the electric motor 170. The junction box serves to control the power transferred to the battery 190 and control the power stored in the battery 190 to be transferred to peripheral components. That is, the junction box controls the power of the battery 190 to be transferred to the converter, the inverter, etc. The motor drive is an electronic control device that controls the electric motor 170 and may perform torque control, speed control, position control, etc., of the electric motor 170.

[0057] Meanwhile, referring to FIGS. 6 and 7, a first inlet 102 may be formed in the rear surface portion 100b of the body frame 100 to allow air for cooling the electric motor 170, the hydraulic pump 180, and electric devices, which are disposed at the rear inside the body frame 100, to be introduced. The first inlet 102 may include one or more long holes 102a that longitudinally extend in the horizontal direction. Cold air introduced through the first inlet 102 may be discharged to the outside through the cooling fan 110 after sequentially passing through the electric motor 170, the hydraulic pump 180, the electric devices, the radiator 120, and the oil cooler 130 that are disposed at the rear.

[0058] In this way, because the first inlet 102 is formed in the rear surface portion 100b of the body frame 100, the electric motor 170, the hydraulic pump 180, the electric devices that are disposed at the rear can be efficiently cooled.

[0059] Referring to FIGS. 6 and 7, the battery 190 may be disposed on a central portion on the right side with respect to the center line CL inside the body frame 100. More specifically, the battery 190 may be disposed 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 disposed to lean toward the right side surface portion 100d of the body frame 100.

[0060] A second inlet 103 may be formed in the right side surface portion 100d of the body frame 100 to allow air for cooling the battery 190 to be introduced. Cold air introduced through the second inlet 103 may be discharged to the outside through the cooling fan 110 after sequentially passing through the battery 190, the radiator 120, and the oil cooler 130.

[0061] Meanwhile, because a distance from each of the above-described first inlet 102, second inlet 103, and third inlet 104 to the cooling fan 110 disposed at the front is far, the cold air introduced through the first inlet 102, the second inlet 103, and the third inlet 104 reaches the radiator 120 and the oil cooler 130 after passing through several components, and accordingly, the cooling efficiency of the radiator 120 and the oil cooler 130 may not be high.

[0062] That is, referring to FIGS. 3 to 5 and FIG. 7, in order to increase the cooling efficiency of the radiator 120 and the oil cooler 130 that are disposed behind the cooling fan 110, a fourth inlet 105 may be formed in the upper surface portion 100e of the body frame 100, where the radiator 120 and the oil cooler 130 are located, to allow air for cooling the radiator 120 and the oil cooler 130 to be introduced.

[0063] Because cold air introduced through the fourth inlet 105 can directly affect the radiator 120 and the oil cooler 130, the cooling efficiency of the radiator 120 and the oil cooler 130 can be increased.

[0064] According to one example, the fourth inlet 105 may be formed in a form that is inclined and has an open rear in the upper surface portion 100e of the body frame 100. When the fourth inlet 105 is formed in the form that is inclined and has an open rear, hot air that is blown forward by the cooling fan 110 and discharged through the outlet 106 formed in the front surface portion 100a can be prevented from re-entering through the fourth inlet 105 and decreasing the cooling efficiency.

[0065] FIG. 8 is a rear perspective view of an upper slewing body according to another aspect of the present disclosure.

[0066] Referring to FIGS. 7 and 8, the first inlet 102 may include one or more long holes 102a extending in the horizontal direction and an inclined hole 102b extending to be inclined from one end of the long hole 102a. That is, the inclined hole 102b extending from the long hole 102a may be further formed to improve cooling efficiency of the hydraulic tank 130 and the hydraulic pump 180 that are disposed at the rear inside the body frame 100, and preferably, the inclined hole 102b may be formed to be inclined downward to increase the amount of air introduced into the hydraulic tank 130 and the hydraulic pump 180.

[0067] In this way, because internal components and various cooling devices (a cooling fan, a radiator, an oil cooler, an inlet, and an outlet) are disposed in a small electric excavator of the present disclosure to not affect battery cooling while efficiently managing heat generation of hydraulic devices such as a MCV, a hydraulic tank, and a hydraulic pump using a hydraulic oil, which are the largest heat sources, the overall cooling efficiency of the small electric excavator can be improved.

[0068] It should be understood that the present disclosure is not limited to the embodiments described above and illustrated in the drawings. Rather, those of ordinary skill in the art will recognize that many changes and modifications 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 and not for purposes of limitation, and the scope of the present disclosure is set forth in the claims below.Description of reference numerals

[0069] 1000 small electric excavator 10 lower traveling body 20 upper slewing body 30 working device 31 boom 32 arm 33 attachment 100 body frame 100a front surface portion 100b rear surface portion 100c left side surface portion 100d right side surface portion 100e upper surface portion 100f lower surface portion 101 ventilation 102 first inlet 103 second inlet 104 third inlet 105 fourth inlet 106 outlet 107 blocking wall 110 cooling fan 120 radiator 130 oil cooler 140 MCV 150 HVAC 160 hydraulic tank 170 electric motor 180 hydraulic pump 190 battery 200 cabin 300 counterweight CL center line

Examples

Embodiment Construction

[0024]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 disclosure. However, the present disclosure may be implemented in various different forms and thus is not limited to aspects described herein. In addition, parts irrelevant to the description are omitted from the drawings to clearly describe the present disclosure, and like parts are denoted by like reference numerals throughout.

[0025]The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms "comprises," "comprising...

Claims

1. A small electric excavator comprising: a lower traveling body; an upper slewing body; and a working device, wherein the upper slewing body includes a body frame, a cabin installed on a left side on the body frame, and a counterweight installed on a rear of the body frame, inside the body frame, with respect to a center line, a main control valve (MCV) and a hydraulic tank are disposed at a left side, and a cooling fan, a radiator, an oil cooler, a battery, an electric motor, a hydraulic pump, and electric devices are disposed at a right side, one or more inlets through which cold air is introduced are formed in the body frame, an outlet through which hot air is discharged is formed in a front surface portion of the body frame, and the cooling fan is disposed right behind the outlet and configured to blow air inside the body frame forward.

2. The small electric excavator of claim 1, wherein the radiator and the oil cooler are disposed right behind the cooling fan.

3. The small electric excavator of claim 2, wherein the MCV is disposed on a front on the left side with respect to the center line inside the body frame, and a ventilation is formed in a lower surface portion of the body frame, where the MCV is located, to allow heat generated from the MCV to circulate.

4. The small electric excavator of claim 3, wherein a blocking wall for at least partially blocking introduction of air from the left side to the right side with respect to the center line is installed inside the body frame.

5. The small electric excavator of claim 2, wherein the hydraulic tank is disposed on a rear on the left side with respect to the center line inside the body frame, and a third inlet is formed in the lower surface portion of the body frame, where the hydraulic tank is located, to allow air for cooling the hydraulic tank to be introduced.

6. The small electric excavator of claim 2, wherein the electric motor, the hydraulic pump, and the electric devices are disposed on a rear on the right side with respect to the center line inside the body frame, and a first inlet is formed in a rear surface portion of the body frame to allow air for cooling the electric motor, the hydraulic pump, and the electric devices to be introduced.

7. The small electric excavator of claim 2, wherein the battery is disposed behind the radiator and the oil cooler, and a second inlet is formed in a right side surface portion of the body frame to allow air for cooling the battery to be introduced.

8. The small electric excavator of claim 2, wherein a fourth inlet is formed in an upper surface portion of the body frame, where the radiator and the oil cooler are located, to allow air for cooling the radiator and the oil cooler to be introduced.

9. The small electric excavator of claim 6, wherein the first inlet includes a long hole extending in a horizontal direction and an inclined hole extending to be inclined downward from one end of the long hole.

10. The small electric excavator of claim 8, wherein the fourth inlet is formed in a form that is inclined and has an open rear in the upper surface portion of the body frame.

Images