Work machine

Abstract

To provide a work machine provided with a dustproof net that can be easily attached and detached.SOLUTION: A work machine includes: a vehicle body; a work device attached to a front of the vehicle body; a counterweight supported at a rear of the vehicle body; and a building provided in the vehicle body between the work device and the counterweight. Inside the building, the work machine further comprises: an engine; a cooling fan using driving force of the engine to generate cooling air flowing from the outside of the building toward the inside of the building; a heat exchanger disposed at an upstream side of the cooling fan in a flow direction of the cooling air and exchanging heat between a fluid and the cooling air; and a dustproof net disposed at the upstream side of the heat exchanger in the flow direction of the cooling air to collect dust contained in the cooling air. Inside the building, interior components disposed at an upstream side of the dustproof net in the flow direction of the cooling air are housed. In the counterweight, an end positioned at the upstream side in the flow direction of the cooling air is cut out to form a recess allowing the dustproof net to be inserted and removed.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a working machine in which a dust-proof net is disposed indoors.

Background Art

[0002] In a working machine such as a hydraulic excavator, an engine room is disposed between a working device and a counterweight. In the engine room, in addition to an engine, a cooling fan, a heat exchanger, etc., a dust-proof net for collecting dust contained in the cooling air generated by the cooling fan is accommodated.

[0003] When the operating time of the working machine becomes long, the dust-proof net becomes clogged. And as the clogging of the dust-proof net progresses, the supply amount of the cooling air to the heat exchanger decreases, and the heat exchange performance deteriorates. Therefore, it is necessary to periodically remove and clean the dust-proof net (see, for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] A small working machine has a small engine room size and there is no room in the space for accommodating the components of the working machine. Therefore, the dust-proof net may be disposed in a narrow gap between the heat exchanger and other components (for example, an air cleaner, electrical components, etc.).

[0006] In this type of machinery, dustproof nets are typically inserted and removed from above the engine housing. Therefore, each time the dustproof net is attached or removed, the operator must climb up and down into the engine housing, which presents a challenge in terms of work efficiency.

[0007] This invention has been made in view of the above-described circumstances, and its purpose is to provide a work machine equipped with a dustproof net that is easy to attach and detach. [Means for solving the problem]

[0008] To achieve the above objective, the present invention provides a work machine comprising a vehicle body, a work device attached to the front of the vehicle body, a counterweight supported at the rear of the vehicle body, and a building provided on the vehicle body between the work device and the counterweight, wherein the building contains an engine, a cooling fan that generates cooling air flowing from the outside to the inside of the building by the driving force of the engine, a heat exchanger positioned upstream of the cooling fan in the direction of cooling air flow and exchanging heat between a fluid and the cooling air, and a dustproof net positioned upstream of the heat exchanger in the direction of cooling air flow and collecting dust contained in the cooling air, wherein the building contains interior components positioned upstream of the dustproof net in the direction of cooling air flow, and the counterweight has a cutout at the end located upstream in the direction of cooling air flow to form a recess that allows the dustproof net to be inserted and removed. [Effects of the Invention]

[0009] According to the present invention, it is possible to obtain a work machine equipped with a dustproof net that is easy to attach and detach. Other problems, configurations, and effects will be clarified by the following description of embodiments. [Brief explanation of the drawing]

[0010] [Figure 1] This is a side view of a hydraulic excavator, which is a typical example of a work machine according to the present invention. [Figure 2]This is a plan view conceptually showing the layout of the components housed within the interior space of the engine building. [Figure 3] This is a perspective view of the main part of the upper rotating body with the cover removed. [Figure 4] This is a perspective view of the main part of the upper rotating body with the cover and counterweight removed. [Figure 5] This is a perspective view of the key parts around the dustproof unit. [Figure 6] This is a perspective view of the main parts of the dustproof unit with the dustproof net removed. [Figure 7] This is a perspective view of the main parts of the dustproof unit with the dustproof net attached. [Figure 8] This is a plan view of the dustproof unit with the dustproof net attached to the frame. [Figure 9] This is a plan view of the dustproof unit with the protruding piece removed from the slit. [Modes for carrying out the invention]

[0011] Embodiments of the work machine according to the present invention will be described with reference to the drawings. Figure 1 is a side view of a hydraulic excavator 1, which is a representative example of the work machine according to the present invention. In this specification, front, back, left, and right directions are based on the viewpoint of the operator riding and operating the hydraulic excavator 1, unless otherwise specified.

[0012] The hydraulic excavator 1 comprises a lower traveling body 2 and an upper rotating body 3 supported by the lower traveling body 2. The lower traveling body 2 and the upper rotating body 3 are examples of a vehicle body. However, the vehicle body does not have to consist of the lower traveling body 2 and the upper rotating body 3.

[0013] The lower travel body 2 is equipped with a pair of left and right crawlers. When the rotation of the travel motor (not shown) is transmitted and the pair of left and right crawlers rotate, the hydraulic excavator 1 moves. However, the lower travel body 2 may be wheeled instead of having crawlers.

[0014] The upper revolving body 3 is supported by the lower traveling body 2 so as to be rotatable. The upper revolving body 3 mainly includes a revolving frame 5 serving as a base, a front working machine 4 (working device), a counterweight 6, a cab (driver's seat) 7, and an engine house 8 (house).

[0015] The front working machine 4 is attached to the front part of the revolving frame 5 and operates (rises and falls). The front working machine 4 includes a boom 4a supported by the upper revolving body 3 so as to be able to rise and fall, an arm 4b supported by the tip of the boom 4a so as to be able to swing, a bucket 4c supported by the tip of the arm 4b so as to be able to swing, and hydraulic cylinders 4d, 4e, 4f for driving the boom 4a, the arm 4b, and the bucket 4c.

[0016] The counterweight 6 is arranged at the rear part of the revolving frame 5. The counterweight 6 is for taking a weight balance with the front working machine 4 and is a heavy object attached to the rear part of the upper revolving body 3. Also, the counterweight 6 has an outer shape in an arc shape in plan view. And a recess 6a described later with reference to FIG. 3 is formed in the counterweight 6.

[0017] The cab 7 is supported by the revolving frame 5 on the left side of the front working machine 4 and in front of the engine house 8. An internal space for an operator to board and operate the hydraulic excavator 1 is formed in the cab 7. In the internal space of the cab 7, a seat (not shown) on which the operator sits and an operating device (such as a steering wheel, pedals, levers, switches, etc.) operated by the operator sitting on the seat are arranged. And by the operator boarding the cab 7 operating the operating device, the lower traveling body 2 travels, the upper revolving body 3 revolves, and the front working machine 4 operates.

[0018] The engine housing 8 is supported by the swing frame 5 behind the front work implement 4 and the cab 7 and in front of the counterweight 6. That is, the engine housing 8 is provided on the upper swing body 3 between the front work implement 4 and the counterweight 6 in the front-rear direction. The engine housing 8 has an internal space 8a (see FIG. 2) that houses components of the hydraulic excavator 1 (for example, the engine 9, cooling fan 10, heat exchanger 11, dust-proof unit 12, air cleaner 13, and electrical components 14 shown in FIG. 2).

[0019] The engine housing 8 is provided with an openable and closable cover 8b. The cover 8b is configured to be rotatable about a rotation axis extending in the vertical direction at the front end of the engine housing 8. The closed cover 8b closes the internal space 8a of the engine housing 8 and forms part of the left side surface and the left rear surface of the upper swing body 3. On the other hand, the opened cover 8b exposes the internal space 8a of the engine housing 8 to the outside of the hydraulic excavator 1 at a part of the left side surface and the left rear surface of the engine housing 8. Further, a plurality of slits 8c penetrating in the thickness direction are formed in the cover 8b at a position corresponding to the left side surface of the engine housing 8. Therefore, even when the cover 8b is closed, outside air flows into the internal space 8a of the engine housing 8 through the slits 8c.

[0020] FIG. 2 is a plan view conceptually showing the layout of the components housed in the internal space 8a of the engine housing 8. As shown in FIG. 2, the engine 9, cooling fan 10, heat exchanger 11, dust-proof unit 12, air cleaner 13, and electrical components 14 are mainly housed in the internal space 8a of the engine housing 8.

[0021] Engine 9 generates the driving force to operate the hydraulic excavator 1 by mixing fuel (e.g., diesel fuel) and air and burning it. The cooling fan 10 generates cooling air when it rotates in response to the driving force transmitted from engine 9. In this embodiment, the cooling air flows into the internal space 8a through the slit 8c and flows through the internal space 8a from left to right. That is, the cooling fan 10 generates cooling air that flows from the outside to the inside of the engine building 8 through the slit 8c. The cooling fan 10 is positioned upstream of engine 9 in the direction of cooling air flow (on the left side in this embodiment).

[0022] The heat exchanger 11 is located upstream of the cooling fan 10 in the direction of the cooling airflow. The heat exchanger 11 exchanges heat between a fluid (e.g., cooling water, air, refrigerant, fuel) and the cooling air. More specifically, the heat exchanger 11 includes a radiator that exchanges heat between the cooling water that has cooled the engine 9 and the cooling air, an intercooler that exchanges heat between compressed air from a supercharger (not shown) and the cooling air, a condenser that exchanges heat between the refrigerant from an air conditioner (not shown) and the cooling air, and a fuel cooler that exchanges heat between the fuel supplied to the engine 9 and the cooling air.

[0023] The dustproof unit 12 is positioned upstream of the heat exchanger 11 in the direction of cooling airflow. The dustproof unit 12 collects dust contained in the air flowing in through the slit 8c of the cover 8b and supplies the dust-free cooling air to the heat exchanger 11. The detailed configuration of the dustproof unit 12 will be described later with reference to Figure 3 and subsequent figures.

[0024] The air cleaner 13 and electrical components 14 are positioned upstream of the dustproof unit 12 with respect to the direction of cooling airflow. The air cleaner 13 collects dust contained in the air supplied to the engine 9. The electrical components 14 include components (e.g., controller, relay, fusible link, disconnect switch, etc.) that electrically control the operation of the hydraulic excavator 1. In this embodiment, the air cleaner 13 and electrical components 14 are positioned in the space between the cover 8b and the dustproof unit 12. However, the components (interior components) positioned in the space between the cover 8b and the dustproof unit 12 are not limited to the air cleaner 13 and electrical components 14, but may also include a battery, urea tank, reserve tank, etc.

[0025] The heat exchanger 11 and the dustproof unit 12 are panel-shaped members that extend in directions intersecting (perpendicular to) the direction of cooling airflow (i.e., vertical and front-to-back directions). The heat exchanger 11 and the dustproof unit 12 also have gaps that penetrate in the thickness direction, allowing the cooling air to pass through. Therefore, the cooling air generated by the cooling fan 10 flows into the internal space 8a through the slit 8c, passes between the components arranged between the cover 8b and the dustproof unit 12, has dust removed as it passes through the dustproof unit 12, exchanges heat with the fluid as it passes through the heat exchanger 11, and is discharged from the internal space 8a through slits (not shown) provided on the top and right sides of the engine building 8.

[0026] Figure 3 is a perspective view of the main parts of the upper rotating body 3 with the cover 8b removed. Figure 4 is a perspective view of the main parts of the upper rotating body 3 with the cover 8b and counterweight 6 removed. Figure 5 is a perspective view of the main parts around the dustproof unit 12. Figure 6 is a perspective view of the main parts of the dustproof unit 12 with the second dustproof net 21 removed. Figure 7 is a perspective view of the main parts of the dustproof unit 12 with the second dustproof net 21 attached.

[0027] As shown in Figure 3, the recess 6a is formed by cutting out a portion of the left end of the counterweight 6 (the upstream end in the direction of cooling airflow). The recess 6a also penetrates the counterweight 6 in the thickness direction. When the cover 8b is opened, the recess 6a exposes a portion of the left rear surface of the engine building 8 to the outside of the hydraulic excavator 1. The amount of cutouts at the upper and lower ends of the counterweight 6 may be set to be smaller than the amount of cutout at the center of the counterweight 6 in the vertical direction (the position facing the dustproof nets 20 and 21, which will be described later).

[0028] As shown in Figure 4, the slewing frame 5 includes a center frame 5a, a D-pipe 5b, and a corner frame 5c. The center frame 5a is a member that constitutes the central part of the slewing frame 5 and is rotatably supported by the lower traveling body 2 via a slewing bearing (not shown). The D-pipe 5b is a hollow member with a D-shaped cross-section. The D-pipe 5b extends in the front-rear direction from the left end of the slewing frame 5. The corner frame 5c connects the left rear corner of the center frame 5a to the rear end of the D-pipe 5b. The D-pipe 5b and corner frame 5c are also located on the right side of the slewing frame 5.

[0029] As shown in Figures 3 and 4, the air cleaner 13 and electrical components 14 are supported by a common bracket 15. The bracket 15 extends vertically as a whole. The bracket 15 supports the air cleaner 13 and electrical components 14 at a position spaced upstream from the dustproof unit 12 in the direction of cooling airflow. The bracket 15 consists of a first support portion 16, a second support portion 17, and a handhold 18.

[0030] The first support section 16 is supported by the top wall of the engine building 8. The first support section 16 supports the air cleaner 13. The second support section 17 is supported by the corner frame 5c. The second support section 17 supports the electrical components 14. In other words, the second support section 17 supports the electrical components 14 below the air cleaner 13.

[0031] Furthermore, the handhold 18 is supported at its upper end by the first support portion 16 and at its lower end by the second support portion 17. In other words, the handhold 18 is double-supported by the first support portion 16 and the second support portion 17. The handhold 18 is the part that an operator grips to maintain their posture while working with the cover 8b open.

[0032] The dustproof unit 12 consists of a frame 19 fixed to the engine building 8, and a first dustproof net 20 and a second dustproof net 21 (hereinafter, these may be collectively referred to as "dustproof nets 20 and 21") that are detachably supported by the frame 19. The number of dustproof nets provided in the dustproof unit 12 is not limited to two; it may be one or three or more.

[0033] As shown in Figures 3 and 4, when the cover 8b is opened, the dustproof unit 12, air cleaner 13, and electrical components 14 are exposed. However, the operator cannot remove the dustproof nets 20 and 21 from the frame 19 to the left because the air cleaner 13 and electrical components 14 get in the way. Therefore, as shown in Figure 5, the dustproof nets 20 and 21 according to this embodiment are configured to be detachable from the frame 19 in the front-rear direction through the recess 6a of the counterweight 6. The configuration for attaching and detaching the dustproof nets 20 and 21 to the frame 19 will be described in detail below.

[0034] As shown in Figure 5, the frame 19 is a frame-shaped member with an opening formed in the center. The opening of the frame 19 is set to be larger than the heat exchanger 11. The frame 19 has a rectangular (more specifically, rectangular) outer shape. The frame 19 is composed of an upper side 22, a lower side 23, a front side 24, a rear side 25, and an intermediate side 26. Each of the sides 22 to 26 is a rod-shaped member (for example, an L-shaped angle).

[0035] The upper edge 22 and the lower edge 23 are spaced apart vertically, and each extends in the front-to-back direction. The front edge 24 is connected to the front ends of the upper edge 22 and the lower edge 23 and extends vertically. The rear edge 25 is connected to the rear ends of the upper edge 22 and the lower edge 23 and extends vertically. The middle edge 26 extends in the front-to-back direction between the upper edge 22 and the lower edge 23 and is connected to the front edge 24 and the rear edge 25. In other words, the opening of the frame 19 is divided into two parts vertically by the middle edge 26.

[0036] Furthermore, the frame 19 is provided with guide sections 27 and 28. Guide sections 27 and 28 are members that guide the dustproof nets 20 and 21 that are attached to and removed from the frame 19. Guide section 27 is attached to the upper edge 22 and guides the upper end of the first dustproof net 20 that is inserted into and removed from the frame 19. Guide section 28 is attached to the lower edge 23 and guides the lower end of the second dustproof net 21 that is inserted into and removed from the frame 19.

[0037] Guide sections 27 and 28 are inclined with respect to the extension direction (i.e., the front-to-back direction) of the dustproof nets 20 and 21 attached to the frame 19. More specifically, the ends of each guide section 27 and 28 are inclined such that they are located further to the left (upstream in the direction of cooling airflow) as they are towards the rear of the upper rotating body 3. In other words, the guide sections 27 and 38 are inclined such that the distance between them and the frame 19 increases as they are towards the inlet side (i.e., the rear side) where the dustproof nets 20 and 21 are inserted into the frame 19. That is, the dustproof nets 20 and 21 are inserted diagonally to the right and forward from the left rear to the right front along the guide sections 27 and 28, and removed diagonally to the left and backward from the right front to the left rear.

[0038] Although not shown in Figure 5, a guide portion for guiding the lower end of the first dustproof net 20 inserted into and removed from the frame 19, and a guide member for guiding the upper end of the second dustproof net 21 inserted into and removed from the frame 19 may be attached to the intermediate side 26.

[0039] Furthermore, as shown in Figure 5, the frame 19 is provided with contact portions 29 and 30. The contact portions 29 and 30 are parts that restrict the front-to-back position of the dustproof nets 20 and 21 when the front ends (downstream ends in the insertion direction) of the dustproof nets 20 and 21 inserted into the frame 19 come into contact with them. The contact portion 29 is attached to the front edge 24 above the middle edge 26 and restricts the position of the front end of the first dustproof net 20. The contact portion 30 is attached to the front edge 24 below the middle edge 26 and restricts the position of the front end of the second dustproof net 21.

[0040] Furthermore, as shown in Figures 5 and 6, the frame 19 is provided with protruding pieces 31 and 32. The protruding pieces 31 and 32 are the parts that enter the slits 33 and 35, which will be described later, when the dustproof nets 20 and 21 are attached to the frame 19. The protruding pieces 31 and 32 also have through holes that penetrate in the vertical direction. The protruding piece 31 protrudes to the left from the rear edge 25 (upstream in the direction of cooling airflow, in other words, the side facing the dustproof net 20) at two locations above the middle edge 26. The protruding piece 32 protrudes to the left from the rear edge 25 (upstream in the direction of cooling airflow, in other words, the side facing the dustproof net 21) at two locations below the middle edge 26.

[0041] The dustproof nets 20 and 21 are panel-shaped members in which a net is attached to a frame with an opening formed in the center. Furthermore, the area of ​​the surface of the dustproof nets 20 and 21 perpendicular to the direction of cooling airflow is set to be larger than the area of ​​the opening of the frame 19 which is divided into two by the middle side 26. The first dustproof net 20 is attached to the top side 22, front side 24, rear side 25, and middle side 26. The second dustproof net 21 is attached to the bottom side 23, front side 24, rear side 25, and middle side 26. In other words, the dustproof nets 20 and 21 are attached to the frame 19 spaced apart in the vertical direction. The gap between the dustproof nets 20 and 21 is closed by the middle side 26.

[0042] The first dustproof net 20 is provided with slits 33 that penetrate in the thickness direction and a handle 34 for the operator to grip when attaching or detaching the first dustproof net 20. The slits 33 are provided at two locations spaced apart vertically at the rear end (upstream end in the insertion direction) of the first dustproof net 20. The handle 34 is positioned between the pair of slits 33 at the rear end (upstream end in the insertion direction) of the first dustproof net 20.

[0043] The second dustproof net 21 is provided with slits 35 that penetrate in the thickness direction and a handle 36 for the operator to grip when attaching or detaching the second dustproof net 21. The slits 35 are provided at two locations spaced apart vertically at the rear end (upstream end in the insertion direction) of the second dustproof net 21. The handle 36 is positioned between the pair of slits 35 at the rear end (upstream end in the insertion direction) of the second dustproof net 21.

[0044] Next, the positional relationship between the recess 6a of the counterweight 6 and the dustproof unit 12, and the inclination angles of the guide sections 27 and 28 will be explained with reference to Figures 8 and 9. Figure 8 is a plan view of the dustproof unit 12 with the dustproof net 20 attached to the frame 19. Figure 9 is a plan view of the dustproof unit 12 with the protruding piece 31 removed from the slit 33. The following explanation will focus on the first dustproof net 20, but the same applies to the second dustproof net 21.

[0045] As shown in Figure 8, the first dustproof net 20 attached to the frame 19 extends in the front-rear direction. When the upper rotating body 3 is viewed from above in a plan view, the extension line L1 of the first dustproof net 20 attached to the frame 19 coincides with the counterweight 6. In other words, the recess 6a of the counterweight 6 is located upstream of the extension line L1 in the direction of cooling airflow. Therefore, the first dustproof net 20 cannot be inserted into or removed from the frame 19 along the extension line L1.

[0046] Furthermore, as shown in Figure 9, when the upper rotating body 3 is viewed from above in a plan view, the extension line L2 of the first dustproof net 20, which is inclined guided by the guide sections 27 and 28, coincides with the recess 6a of the counterweight 6. In other words, the recess 6a of the counterweight 6 is located on the extension line L2. Therefore, the first dustproof net 20 can be inserted into and removed from the frame 19 along the extension line L2.

[0047] Furthermore, as shown in Figure 9, extension line L2 is positioned between extension lines L3 and L4. Extension line L3 coincides with the extension direction of the first dustproof net 20 when the front end of the first dustproof net 20 is in contact with the contact portion 29 and the protruding piece 31 is in contact with the slit 33. Extension line L4 coincides with the extension direction of the first dustproof net 20 when the front end of the first dustproof net 20 is in contact with the air cleaner 13 and electrical components 14 when the front end of the first dustproof net 20 is in contact with the contact portion 29. In other words, the inclination angle of the guide portions 27 and 28 of the upper rotating body 3 with respect to the front-rear direction (the inclination angle of extension line L2 with respect to the front-rear direction) is set to be greater than the inclination angle of extension line L3 with respect to the front-rear direction and smaller than the inclination angle of extension line L4 with respect to the front-rear direction.

[0048] Next, the method for inserting the first dustproof net 20 into the frame 19 will be described. First, the operator inserts the first dustproof net 20 into the internal space 8a of the engine building 8 through the recess 6a of the counterweight 6. As a result, the front end of the first dustproof net 20 comes into contact with the upper edge 22 and the middle edge 26, and is guided to the guide portion 27 by being inserted further inward.

[0049] Next, the operator inserts the first dustproof net 20, guided by the guide section 27, into the back of the internal space 8a along the extension line L2. When the front end of the first dustproof net 20 contacts the contact section 29, the operator brings the rear end of the first dustproof net 20 into contact with the rear edge 25 of the frame 19. This causes the protruding piece 31 to enter the slit 33. The operator then inserts the pin 37 into the through hole of the protruding piece 31 that has entered the slit 33. This attaches the first dustproof net 20 to the frame 19. The method for inserting the second dustproof net 21 is the same.

[0050] Next, the method for removing the first dust net 20 from the frame 19 will be described. First, the operator removes the pin 37 from the through hole of the protruding piece 31. Next, the operator separates the rear end of the first dust net 20 from the rear edge 25 of the frame 19 until the first dust net 20 contacts the guide portion 27. Next, the operator pulls the first dust net 20, guided by the guide portion 27, to the left rear along the extension line L2. As a result, the first dust net 20 is removed from the internal space 8a of the engine building 8 through the recess 6a of the counterweight 6. The method for removing the second dust net 21 is the same.

[0051] According to the above embodiment, the dust nets 20 and 21 can be inserted and removed horizontally through the recess 6a of the counterweight 6. This eliminates the need for the operator to climb up and down into the engine building 8 each time the dust nets 20 and 21 are attached or removed. As a result, attaching and detaching the dust nets 20 and 21 becomes easier. The weight of the counterweight 6 reduced by forming the recess 6a can be compensated for, for example, by increasing the height of the counterweight 6.

[0052] Furthermore, according to the above embodiment, by guiding the dustproof nets 20 and 21, which are inserted into and removed from the frame 19, by the guide portions 27 and 28, it is possible to prevent interference with the counterweight 6, air cleaner 13, and electrical components 14 when inserting or removing the dustproof nets 20 and 21.

[0053] Furthermore, according to the above embodiment, the insertion and removal direction of the dustproof nets 20 and 21 (i.e., the direction of the extension line L2) is inclined upstream of the cooling airflow direction with respect to the front-rear direction. As a result, the recess 6a can be made smaller (i.e., the amount of cutout for the counterweight 6 can be reduced) compared to the case where it is not inclined. This minimizes the increase in height required to compensate for the weight of the counterweight 6. Consequently, the rearward visibility of the operator seated in the cab 7 can be ensured.

[0054] Furthermore, according to the above embodiment, by dividing the dustproof nets 20 and 21 into two vertical sections, insertion and removal from the frame 19 becomes even easier compared to a single-piece dustproof net. Moreover, according to the above embodiment, by closing the gap between the dustproof nets 20 and 21 at the intermediate edge 26, it is possible to prevent dust from adhering to the surface of the heat exchanger 11.

[0055] Furthermore, the present invention exhibits particularly advantageous effects when applied to small work machines, often referred to as "small swing machines." However, the present invention is not limited to small work machines and can also be applied to large work machines. Moreover, the present invention is not limited to hydraulic excavators 1, but can also be applied to motor graders, wheel loaders, cranes, and the like.

[0056] The embodiments described above are illustrative for explaining the present invention and are not intended to limit the scope of the invention to those embodiments only. Those skilled in the art can implement the present invention in various other forms without departing from the spirit of the invention. [Explanation of Symbols]

[0057] 1. Hydraulic excavator (working machine) 2. Lower running body (vehicle body) 3. Upper rotating body (vehicle body) 4. Front work equipment (working device) 4a Boom 4b Arm 4c bucket 4d, 4e, 4f Hydraulic Cylinders 5. Swivel Frame 5a Center frame 5b D pipe 5c corner frame 6 counterweights 6a Recess 7 Cab 8. Engine building (building) 8a Interior space 8b Cover 8c slit 9 Engines 10 Cooling Fans 11 Heat exchanger 12 Dustproof Units 13. Air cleaner 14. Electrical components 15 brackets 16 1st support part 17 Second support part 18 Handholds 19 Frame 20. First dustproof net 21. Second dustproof net 22 Top 23 Bottom edge 24 Front side 26 Middle side 27,28 Guide Section 29,30 Contact part 31,32 Projecting piece 33,35 Slits 34,36 Handle 37 pins

Claims

1. The car body and A working device attached to the front of the vehicle body; A counterweight supported on a rear portion of the vehicle body; A building provided on the vehicle body between the working device and the counterweight; Equipped with Inside the building, The engine, a cooling fan that generates cooling air flowing from the outside to the inside of the building by the driving force of the engine; a heat exchanger disposed upstream of the cooling fan in a flow direction of the cooling air, for exchanging heat between the fluid and the cooling air; a dustproof net disposed upstream of the heat exchanger in a flow direction of the cooling air and configured to collect dust contained in the cooling air; In a work machine comprising: Inside the building, An interior part is housed in the compartment, the interior part being arranged upstream of the dustproof net in the direction of the cooling air flow. The counterweight has: The end portion located on the upstream side in the flow direction of the cooling air is cut out to form a recess that allows the dustproof net to be inserted and removed. A working machine characterized by:

2. 2. The work machine according to claim 1, Inside the building, a frame for detachably supporting the dustproof net is fixed upstream of the heat exchanger in the direction of flow of cooling air; The frame body includes: A guide portion for guiding the dustproof net when it is inserted into or removed from the frame body is provided on each of the upper and lower edges extending in the front-rear direction and spaced apart from each other in the vertical direction. A working machine characterized by:

3. 3. The work machine according to claim 2, The guide portion is The dustproof net is inclined so that the gap between the dustproof net and the frame body becomes wider toward the entrance side where the dustproof net is inserted. A working machine characterized by:

4. 4. The working machine according to claim 3, The frame body is a rear side that connects rear ends of the upper side and the lower side to each other and extends in the up-down direction; a protruding piece protruding from the rear side toward a side facing the dustproof net, The dustproof net includes: A slit is formed in which the protruding piece enters while being supported by the frame body, The inclination angle of the guide portion with respect to the front-rear direction of the vehicle body is larger than the angle of the dustproof net when the tip of the protruding piece contacts the slit and is smaller than the angle of the dustproof net when it contacts the interior part. A working machine characterized by:

5. 5. The working machine according to claim 4, The recess of the counterweight is When the vehicle body is viewed from above, the dustproof net is provided on the upstream side in the flow direction of the cooling air from the extension line of the dustproof net supported by the frame body, and on the extension line of the dustproof net guided by the guide section and inclined. A working machine characterized by:

6. 3. The work machine according to claim 2, The frame body is an intermediate side extending in the front-rear direction between the upper side and the lower side; The dustproof net is A first dustproof net detachably supported on the upper side and the middle side; a second dustproof net detachably supported on the middle side and the lower side. A working machine characterized by:

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