JP2011235673A - Dust-proof device for construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dust-proof device for a construction machine in which the clogging of dust-proof nets in a specified zone is suppressed to elongate the operation time of the dust-proof device.SOLUTION: The second dust-proof net 9 is arranged at the upstream side of the cooling air of the first dust-proof net 8 and in a zone corresponding to a cooling flow path to a radiator 11 being a heat exchanger having the lowest ventilation resistance. Due to the installation of the secure dust-proof net 9, the second dust-proof net 9 serves as ventilation resistance, the ventilation resistance to the cooling air passing through the second dust-proof net 9, the first dust-proof net 8, and the radiator 11 becomes high and the cooling air is restrained from being concentrated in the zone corresponding to the cooling flow path to the radiator 11. Dust which is concentrated and accumulated in the opposed zone of the first dust-proof net 8 to the radiator 11 in a conventional technology is accumulated dispersedly in the opposed zone of the dust-proof net 8 to an oil cooler 12 or an intercooler 13. As a result, the operation time of the dust-proof device can be made longer as compared with a conventional art.

Description

  The present invention relates to a dustproof device for a construction machine such as a hydraulic excavator, and more particularly to a dustproof device for a construction machine provided with a dustproof net that captures dust in cooling air.

  In construction machines such as hydraulic excavators, excavation work is performed by operating actuators that drive booms, arms, and buckets. A hydraulic pump is driven by an engine as a power source, and hydraulic actuators are pumped to a hydraulic cylinder to operate each actuator. When the engine and hydraulic pump are operated, heat is generated in the engine and hydraulic fluid. Therefore, heat exchangers such as radiators and oil coolers are installed for cooling engine coolant and hot hydraulic oil. The cooling air induced by the cooling fan passes through the heat exchanger, whereby the heat exchanger is cooled. A device for cooling the heat exchanger is called a cooling device.

  Furthermore, due to recent regulations on exhaust gas, construction machines equipped with an intercooler are becoming mainstream in order to reduce the concentration of nitrogen oxides and the like in the exhaust gas. The intercooler cools the engine intake air that is turbo-charged and adiabatically compressed to a predetermined temperature, increases the charging efficiency, and lowers the combustion temperature, thereby suppressing the generation of NOx (nitrogen oxides) in the exhaust. . In addition, a condenser for cooling the refrigerant of the air conditioner may be installed.

  Such construction machines often operate in spaces where dust is floating around, such as industrial waste treatment plants and forestry, so that the surrounding dust is not sucked into the heat exchanger together with the cooling air. In addition, a dustproof net is provided on the upstream side of the cooling air of the heat exchanger so as to face the heat exchanger.

  The dust-proof net captures dust in the cooling air, but if dust accumulates on the dust-proof net and becomes clogged, the amount of cooling air is reduced and the cooling performance of the heat exchanger is reduced. Therefore, it is necessary to frequently clean the dustproof net to remove clogging. In a so-called series arrangement type heat exchanger unit that has been widely employed in the past, it is necessary to provide a dustproof net for each heat exchanger, and it is also necessary to clean the dustproof net individually.

  In order to improve the ease of cleaning of such a dustproof net, the technique described in Patent Document 1 has been proposed. The dustproof device described in Patent Document 1 is provided with a common dustproof net so as to face a parallel heat exchanger unit in which heat exchangers such as a radiator, an oil cooler, and an intercooler are arranged in parallel. Thereby, it is only necessary to clean one dustproof net, and the ease of cleaning can be improved.

JP 2006-52689 A

  As described above, the dustproof device described in Patent Document 1 can improve the ease of cleaning by providing a common dustproof net upstream of the heat exchanger units arranged in parallel. As a result, the following new problems occur.

  Heat exchangers such as a radiator, an oil cooler, and an intercooler constituting the heat exchanger unit have different ventilation resistances. Cooling air is concentrated in heat exchangers with low ventilation resistance. Therefore, the initial cooling performance of the heat exchanger with low ventilation resistance is high. However, when the cooling air is concentrated in a specific range, dust sucked together with the cooling air is concentrated and accumulated in a specific range of the dust-proof net (a range corresponding to the cooling flow path to the heat exchanger with low ventilation resistance). In this range, the dustproof net is clogged. Due to the clogging of the dustproof net, the cooling performance of a specific heat exchanger may be significantly reduced. For example, if the dustproof net is not cleaned and it continues to operate, the cooling performance of the radiator is lowered, and the engine is often overheated. Therefore, even if the problem concerning heat exchangers other than a specific heat exchanger does not arise, it was necessary to clean a dustproof net frequently. On the other hand, since cleaning of the dustproof net involves attaching and detaching the dustproof net, it is preferable that the frequency of cleaning is low (the operation time of the dustproof device is long). Thus, although the dustproof device according to the prior art is easy to clean, there is a problem that the operation time is short.

  The ventilation resistance of each heat exchanger is determined by various factors such as the shape of the apparatus, and it is difficult to make the ventilation resistance of each heat exchanger uniform.

  An object of the present invention is to provide a dustproof device for a construction machine that can suppress clogging in a specific range of a dustproof net and extend the operation time.

  (1) To achieve the above object, the present invention cools a heat exchanger unit composed of a plurality of heat exchangers arranged in parallel by cooling air induced by a cooling fan and taken in from an opening. In the dust-proof device of the construction machine provided with a first dust-proof net provided in the apparatus, facing the heat exchanger unit at a position upstream of the cooling air of the heat exchanger unit, and capturing dust in the cooling air, In the range corresponding to the cooling flow path to the heat exchanger having the lowest ventilation resistance among the plurality of heat exchangers on the cooling air upstream side of the first dustproof net, facing the first dustproof net. A second dustproof net is provided.

  In the present invention configured as described above, since the second dustproof net also becomes ventilation resistance by the installation of the second dustproof net, it passes through the second dustproof net, the first dustproof net, and the heat exchanger having the lowest ventilation resistance. Ventilation resistance to cooling air is increased. Concentration of the cooling air in a range corresponding to the cooling flow path to the heat exchanger having the lowest ventilation resistance is suppressed. On the other hand, the wind speed of the cooling air to other ranges is higher than before.

  As a result, the dust that has been concentrated in a specific range in the prior art is distributed and accumulated. As a result, the period until the next cleaning is required (the operation time of the dustproof device) can be made longer than in the past.

  (2) In the above (1), preferably, the second dustproof net has a main surface portion facing the first dustproof net and a side surface portion protruding from the main surface portion to the cooling air downstream side.

  Thereby, even when clogging occurs in the second dustproof net main surface portion, the cooling air cools the heat exchanger via the second dustproof net side surface portion, and the cooling performance of the heat exchanger can be maintained.

  (3) In the above (1), preferably, the second dustproof net is downstream of the cooling air from the heat exchanger side having the lowest ventilation resistance toward the heat exchanger side adjacent to the heat exchanger having the lowest ventilation resistance. Inclined to approach the side.

  (4) In the above (3), preferably, the heat exchanger having the lowest ventilation resistance is adjacent to other heat exchangers on both sides, and the second dustproof net has a ridge line between the first surface and the second surface. And the first surface of the second dustproof net approaches the cooling air downstream side from the heat exchanger side having the lowest ventilation resistance toward one heat exchanger side adjacent thereto. The second surface of the second dustproof net is inclined so as to approach the cooling air downstream side from the heat exchanger side having the lowest ventilation resistance toward the other heat exchanger side adjacent thereto. .

  Since the second dustproof net has an inclination in this way, a part of the dust accumulated on the second dustproof net is urged along the inclination by the cooling air and is adjacent to the heat exchanger having the lowest ventilation resistance. It moves toward the heat exchanger and is captured and deposited in the first dust net. Thereby, the dispersion | distribution effect by installation of a 2nd dustproof net can be improved.

  (5) In the above (1), preferably, the second dustproof net is added to the existing first dustproof net.

  Thus, since it is the structure which only installed the 2nd dustproof net in the prior art, the conventional dustproof apparatus can be used effectively as it is.

  ADVANTAGE OF THE INVENTION According to this invention, clogging in the specific range of a dust-proof net can be suppressed, and dust can be disperse | distributed. As a result, the operation time of the dustproof device can be extended.

It is sectional drawing which shows the engine room with which the dustproof apparatus of the construction machine concerning 1st Embodiment of this invention is provided. It is a top view of an engine room. It is a perspective view of a dustproof device. 1 is an overall view of a hydraulic excavator that is an example of a construction machine to which the present embodiment is applied. It is sectional drawing of the conventional dustproof apparatus. FIG. 3 is a cross-sectional view of a dustproof device for explaining a first effect of the first embodiment. It is sectional drawing of the dustproof apparatus for demonstrating the 2nd effect of 1st Embodiment. It is sectional drawing of the dustproof apparatus of 2nd Embodiment. It is sectional drawing of the dustproof apparatus of 3rd Embodiment. It is sectional drawing of the dustproof apparatus of 4th Embodiment. It is sectional drawing of the dustproof apparatus of 5th Embodiment. It is sectional drawing of the dustproof apparatus of 6th Embodiment. It is sectional drawing of the dustproof apparatus of 7th Embodiment.

<First Embodiment>
A first embodiment of the present invention will be described with reference to the drawings.

~Constitution~
FIG. 1 is a cross-sectional view showing an engine room 1 provided with a dustproof device for a construction machine according to a first embodiment of the present invention. FIG. 2 is a plan view of the engine compartment 1. The configuration of the first embodiment will be described with reference to FIGS.

  The dustproof device of the present embodiment is provided in the engine compartment 1. The engine compartment 1 is covered with a building cover 27 on the outside, and openings 21 and 22 for taking in cooling air are formed in the building cover 27. In the engine chamber 1, a heat exchanger unit 10, a fuel cooler 14, a condenser 15, a shroud 4 provided on the downstream side of the heat exchanger unit 10, and cooling air for cooling the heat exchanger unit 10 are induced. A cooling fan 3 is provided, and these constitute a cooling device.

  The engine 2 is supported in the engine chamber 1 via an engine mount (not shown). A hydraulic pump (not shown) is attached to a drive shaft on the flywheel side of the engine 2. The cooling fan 3 is attached to a drive shaft opposite to the hydraulic pump, and is driven by the engine 2 to induce cooling air.

  The heat exchanger unit 10 is disposed to face the cooling fan upstream of the cooling fan 3, and includes a radiator 11, an oil cooler 12, and an intercooler 13 that are arranged in parallel with the cooling air direction. In the present embodiment, for convenience of explanation, the radiator 11 is disposed in the center, the oil cooler 12 is disposed adjacent to the left side of the radiator 11 when viewed from the upstream side of the cooling air, and the intercooler 13 is disposed on the upstream side of the cooling air. It is assumed that they are arranged adjacent to the right side of the radiator 11 when viewed from the side. The radiator 11 is a heat exchanger having the lowest ventilation resistance among the heat exchangers 11 to 13, the intercooler 13 is a heat exchanger having the next lowest ventilation resistance, and the oil cooler 12 is the heat exchangers 11 to 13. It is assumed that the heat exchanger has the highest ventilation resistance. In addition, the arrangement of the heat exchangers 11 to 13 and the order of the airflow resistance are assumed for convenience of explanation, and are appropriately changed depending on design convenience.

  The fuel cooler 14 and the air conditioner condenser 15 are arranged in parallel so as to face each other on the cooling air upstream side of the heat exchanger unit 10.

  The cooling fan 3 is a so-called axial fan, and is attached to the auxiliary rotating shaft 34. A fan pulley 32 is fixed to the auxiliary rotating shaft 34 so as to be at a position corresponding to the crank pulley 31 of the engine crankshaft 35. A fan belt 33 is stretched between the crank pulley 31 and the fan pulley 32. The cooling fan 3 includes a boss 3a fixed to an auxiliary rotating shaft 34 to which a driving force from the engine crankshaft 35 is transmitted, and a plurality of blades 3b fixed around the boss 3a. Driven by the rotation of the shaft 34, a negative pressure is generated between the cooling fan 3 and the heat exchanger unit 10 to induce cooling air.

  A battery 16 is installed upstream of the cooling air at the bottom of the engine compartment 1. The battery 16 turns the cell motor as a power source for electrical components, for example, when the engine is started.

  The dustproof device of this embodiment is comprised from the 1st dustproof net 8, the 2nd dustproof net 9, and the member which fixes these. FIG. 3 is a perspective view of the dustproof device.

  The first dust net 8 captures dust in the cooling air taken from the openings 21 and 22 and is located on the upstream side of the heat exchanger unit 10 on the downstream side of the cooling air of the fuel cooler 14 and the condenser 15. To do. Brackets 18a and 18b are provided on the upper frame 17a and the lower frame 17b for fixing the heat exchanger unit 10, respectively. The upper end 8a (not shown) of the first dust net 8 is fixed to the bracket 18a by a bolt 20a, and the lower end 8b (not shown) of the first dust net 8 is fixed to the bracket 18b by a support structure member 20b. ing. Thereby, the first dustproof net 8 is vertically installed so as to face the heat exchanger unit 10.

  The second dust-proof net 9 is a characteristic configuration of the present embodiment, and is provided on the cooling flow path to the radiator 11 that is the heat exchanger upstream of the first dust-proof net 8 and has the lowest ventilation resistance. Located in the corresponding range. The brackets 18a and 18b for fixing the first dustproof net 8 are provided with additional brackets 19a and 19b, respectively, by bolting 20a and a supporting structure member 20b. The upper end portion 9a of the second dustproof net 9 is fixed to the additional bracket 19a by bolts 20a and 20c, and the lower end portion 9b of the second dustproof net 9 is fixed to the additional bracket 19b by the supporting structural member 20b and bolt stops 20d. That is, the shaft portion of the bolt stop 20a passes through the through hole of the first dustproof net 8, the through hole of the second dustproof net 9, and the through hole of the additional bracket 19, and is screwed and locked with the bolt stop 20a butterfly screw. The support structure member 20 b sandwiches the second dust-proof net 9, the additional bracket 19, and the bracket 18, whereby the second dust-proof net 9 and the additional bracket 19 are fixed to the bracket 18. Thus, the second dust net 9 is vertically installed so as to face the first dust net 8.

  The second dust-proof net 9 has a main surface portion 9c facing the first dust-proof net 8 and a side surface portion 9d protruding from the main surface portion 9c to the cooling air downstream side, and has a substantially U-shaped shape. The additional bracket 19 has a substantially Ω-shape corresponding to the substantially U-shape of the second dust-proof net 9 (exactly, a shape in which flat bars protrude from both sides of the substantially U-shape, the same applies hereinafter). The side surface portion 9d is in contact with the first dustproof net 8 so that there is no gap.

  The first dust-proof net 8 and the second dust-proof net 9 have a mesh structure, and in a normal case, the mesh roughness is configured with an interval smaller than the fin pitch interval of the heat exchanger.

  FIG. 4 is an overall view of a hydraulic excavator that is an example of a construction machine to which the present embodiment is applied.

  The excavator 101 includes a frame 104 that constitutes an upper swing body 103 on a lower traveling body 102, and includes an engine chamber 1, a cabin 105, and a counterweight 106 on the frame 104. Further, a front attachment 110 including a boom 111 and a boom cylinder 112, an arm 113 and an arm cylinder 114, a bucket 115 and a bucket cylinder 116 is provided in front of the vehicle body.

~ Operation ~
Next, the operation of the present embodiment configured as described above will be described.

  When the engine 2 is driven during operation of the hydraulic excavator, the rotation of the crankshaft 35 is transmitted to the auxiliary rotation shaft 34 via the crank pulley 31, the fan belt 33, and the fan pulley 32. Thereby, the cooling fan 3 is driven and rotated. By the rotation of the cooling fan 3, outside air is taken into the engine compartment 1 from the openings 21 and 22 and flows as cooling air from the upstream side to enter the fuel cooler 14, the condenser 15, and the heat exchanger unit 10 (the radiator 11, After cooling the oil cooler 12 and the intercooler 13), the oil cooler 12 and the intercooler 13) are squeezed through the inside of the shroud 4 on the downstream side of the heat exchanger unit 10 and introduced into the suction side of the cooling fan 3. Thereafter, the cooling air blown out from the cooling fan 3 cools the engine 2, the hydraulic pump, and the like on the downstream side of the cooling fan 3, and then is discharged from the openings 23 and 24 to the outside of the engine room 1.

  When the excavator 101 is operated in a place where there is a lot of dust or dust, the cooling air flowing from the openings 21 and 22 flows into the engine compartment 1 with dust. At this time, dust having a particle size smaller than the mesh of the dust-proof nets 8 and 9 passes through the dust-proof nets 8 and 9, and passes between the heat exchanger units 10 by the cooling air in the engine compartment 1 because the specific gravity is small. Then, the cooling air is discharged from the openings 23 and 24 to the outside of the engine compartment 1. On the other hand, dust having a particle size larger than the roughness of the mesh of the dustproof nets 8 and 9 is captured by the dustproof nets 8 and 9. If the dust continues to be trapped and accumulated in the dust nets 8 and 9, clogging occurs, the cooling air volume decreases, and the cooling performance of the heat exchanger decreases. Therefore, it is necessary to clean the dust nets 8 and 9 to remove clogging. The period from when the cleaning is performed to when the next cleaning is performed is called the operation time of the dustproof device.

  The dustproof nets 8 and 9 are cleaned by opening and closing the building cover 27, removing the bolts 20 a, 20 c and 20 d and the supporting structural member 20 b, and adding the additional bracket 19, the second dustproof net 9, and the first dustproof net. Removal is performed in the order of 8. After cleaning the dust-proof nets 8 and 9, the first dust-proof net 8, the second dust-proof net 9 and the additional bracket 19 are fixed to the bracket 18 again by the bolt stops 20a, 20c and 20d and the supporting structural member 20b.

  Dust that is not captured by the dust nets 8 and 9 accumulates at the bottom of the engine compartment 1. Cleaning in the engine room 1 is performed by opening and closing the building cover 27 and using a compressor. The dust accumulated on the bottom of the engine room 1 is blown off by the wind pressure of the compressor and discharged from an opening (not shown) provided on the upstream side of the cooling air at the bottom of the engine room 1.

~effect~
The first effect of the present embodiment configured as described above will be described in comparison with a conventional dustproof device.

  FIG. 5 is a cross-sectional view of a conventional dustproof device for comparison. The same components as those in FIGS. In the first embodiment, the second dustproof net 9 and the additional bracket 19 are provided, whereas the conventional dustproof device does not have these configurations.

  Incidentally, for convenience of explanation, in the heat exchanger unit 10, the intercooler 13, the radiator 11, and the oil cooler 12 are arranged in parallel from the right when viewed from the upstream side of the cooling air, and the radiator 11 is the most ventilated among the heat exchangers 11 to 13. It is assumed that the heat exchanger has a low resistance, the intercooler 13 is the next heat exchanger having the lowest ventilation resistance, and the oil cooler 12 is the heat exchanger having the highest ventilation resistance among the heat exchangers 11 to 13. .

  In the case of such arrangement of the heat exchangers 11 to 13 and the order of the ventilation resistance, the cooling air is concentrated in a range corresponding to the cooling flow path to the radiator 11 disposed in the center and having the lowest ventilation resistance. Therefore, the initial cooling performance of the radiator 11 is high. However, when the cooling air is concentrated in the cooling flow path range to the radiator 11, the dust sucked together with the cooling air is also concentrated and accumulated in the region facing the radiator 11 of the dust-proof net 8. Clogging occurs. If this is left unattended, the cooling performance of the radiator 11 is significantly reduced, and the engine 2 may overheat.

  At this time, in the range of the dust net 8 facing the oil cooler 12 and the intercooler 13, the dust hardly accumulates compared to the range facing the radiator 11, and the problem related to the oil cooler 12 and the intercooler 13 arises. Absent. However, since the problem concerning the radiator 11 may occur, it is necessary to clean the dust-proof net 8 frequently. On the other hand, since cleaning of the dustproof net 8 involves attaching / detaching work of the dustproof net 8, it is preferable that the frequency of cleaning is low (the operation time of the dustproof device is long). Thus, the dustproof device according to the prior art has a problem that the operation time is short.

  FIG. 6 is a cross-sectional view of the dustproof device of the present embodiment for explaining the first effect. The same components as those in FIG. 2 are denoted by the same reference numerals. That is, the dustproof device of this embodiment is obtained by adding the second dustproof net 9 and the additional bracket 19 which are characteristic configurations to the configuration of the conventional dustproof device.

  By the way, the ventilation resistance of each heat exchanger 11-13 is decided by factors, such as a device shape, and adjusting the ventilation resistance of the radiator 11 itself so that the ventilation resistance of each heat exchanger 11-13 may be made uniform, for example. difficult.

  In the present embodiment, the second dust-proof net 9 is provided on the upstream side of the cooling air of the first dust-proof net 8 and in a range corresponding to the cooling flow path to the radiator 11 that is the heat exchanger having the lowest ventilation resistance. Yes. By installing the second dustproof net 9, the second dustproof net 9 also becomes a ventilation resistance, so the ventilation resistance against the cooling air passing through the second dustproof net 9, the first dustproof net 8, and the radiator 11 is increased. Concentration of the cooling air in a range corresponding to the cooling flow path to the radiator 11 is suppressed. On the other hand, the air velocity of the cooling air to the range corresponding to the cooling flow path to the oil cooler 12 and the intercooler 13 is increased as compared with the conventional case.

  As a result, the dust that has been concentrated and accumulated in the range of the conventional technology facing the radiator 11 of the dustproof net 8 is dispersed and accumulated in the range of the dustproof net 8 facing the oil cooler 12 and the intercooler 13 (dispersion). effect). As a result, the period until the next cleaning is required (the operation time of the dustproof device) can be made longer than in the past.

  On the other hand, although the initial cooling performance of the radiator 11 is slightly lowered, the operation time of the dustproof device becomes longer in a state where the required cooling performance of the radiator 11 is maintained. The hydraulic excavator 101 often operates for a long period of time at a site where dust is floating, and an overall plan that considers maintenance is more important than improving the performance of one component (eg, the radiator 11).

  The second effect of this embodiment will be described. As described in the first effect, the second dust-proof net 9 also has ventilation resistance. Here, if the ventilation resistance of the second dust-proof net 9 is too high, the cooling air speed is too low and the original cooling performance of the radiator 11 cannot be obtained. Therefore, the ventilation resistance of the second dustproof net 9 is preferably not too high (low). As a result, although the concentration of the cooling air is suppressed as described in the first effect, the second dustproof net 9 provided in the cooling flow path range to the radiator 11 includes the oil cooler 12 of the dustproof net 8 and the interface. Compared to the range facing the cooler 13, dust is likely to accumulate. That is, the second dust net 9 may be clogged.

  FIG. 7 is a cross-sectional view of the dustproof device of the present embodiment for explaining the second effect. The second dustproof net 9 has a main surface portion 9c facing the first dustproof net 8, and a side surface portion 9d protruding from the main surface portion 9c to the cooling air downstream side.

  Cooling air that cools the radiator 11 passes through the second dust-proof net main surface portion 9 c, the first dust-proof net 8, and the radiator 11. At this time, dust is trapped and deposited on the second dustproof net main surface portion 9c. On the other hand, since the second dustproof net side surface portion 9d is parallel to the cooling air, the dust hardly accumulates on the second dustproof net side surface portion 9d. When clogging occurs in the second dustproof net main surface portion 9c, the cooling air changes the flow path, passes through the second dustproof net side surface portion 9d, the first dustproof net 8, and the radiator 11, and cools the radiator 11.

  Thereby, even when clogging occurs in the second dust-proof net main surface portion 9c, the cooling air cools the radiator 11 via the second dust-proof net side surface portion 9d, and the cooling performance of the radiator 11 can be maintained.

  The third effect of this embodiment will be described. The dustproof device of this embodiment is obtained by adding a second dustproof net 9 and an additional bracket 19 which are characteristic configurations to the configuration of a conventional dustproof device. Further, the second dust-proof net 9 and the additional bracket 19 are fixed by a bolt stop 20 common to the first dust-proof net 8. Thereby, the conventional dustproof device can be effectively used as it is.

Second Embodiment
FIG. 8 is a cross-sectional view of the dustproof device of the second embodiment. Whereas the second dust-proof net 9 of the first embodiment has a main surface portion 9c and a side surface portion 9d, the second dust-proof net 9A of the second embodiment has cooling air from the radiator 11 side toward the oil cooler 12 side. Second dustproof net first surface portion 9Ac that is inclined so as to approach the downstream side, and second dustproof net second surface portion that is inclined so as to approach the cooling air downstream side from the radiator 11 side toward the intercooler 13 side. 9Ad. That is, the second dust-proof net 9 of the first embodiment is substantially U-shaped, whereas the second dust-proof net 9A of the second embodiment is the second dust-proof net first surface portion 9Ac and the second dust-proof net The two-surface portion 9Ad has a mountain shape that is in contact with the ridgeline. The additional bracket 19A has a substantially chevron shape corresponding to the chevron shape of the second dustproof net 9A.

  Also in the present embodiment, the second dustproof net 9A is provided in the range corresponding to the cooling flow path to the radiator 11 that is the heat exchanger upstream of the first dustproof net 8 and has the lowest ventilation resistance. And since the 2nd dustproof net 9A becomes ventilation resistance, the same effect as the 1st effect of a 1st embodiment is acquired.

  Since the second dustproof net 9A does not have the second dustproof net side surface portion 9d of the first embodiment, the second effect of the first embodiment cannot be obtained. However, the following effects are obtained by the inclination of the mountain shape.

  Cooling air that cools the radiator 11 passes through the second dustproof net 9 </ b> A, the first dustproof net 8, and the radiator 11. At this time, dust is trapped and accumulated in the second dust-proof net 9A. Part of the dust accumulated on the second dust-proof net first surface portion 9Ac is energized along the inclination by the cooling air, moves toward the oil cooler 12 side, and in a range facing the oil cooler 12 of the dust-proof net 8. , Trapped and deposited. Part of the dust accumulated on the second dust-proof net second surface portion 9Ad is energized along the inclination by the cooling air, moves toward the intercooler 13 side, and in a range facing the intercooler 13 of the dust-proof net 8. , Trapped and deposited.

  Thereby, the dust deposited on the second dustproof net 9 </ b> A is dispersed and accumulated in a range of the dustproof net 8 facing the oil cooler 12 and the intercooler 13. That is, the first effect of the first embodiment can be improved.

  In addition, the dustproof device of this embodiment adds the 2nd dustproof net 9A and the additional bracket 19A to the structure of the conventional dustproof device, and can obtain the 3rd effect of 1st Embodiment.

<Third Embodiment>
FIG. 9 is a cross-sectional view of the dustproof device of the third embodiment. The second dustproof net 9 of the first embodiment has the main surface portion 9c and the side surface portion 9d, whereas the second dustproof net 9B of the third embodiment has only the main surface portion 9Bc. That is, there is no configuration corresponding to the side surface portion 9d of the second dustproof net 9 of the first embodiment, and the opening 7 is formed.

  The additional bracket 19 for fixing the second dustproof net 9B is the same as the additional bracket 19 of the first embodiment, and has a substantially Ω-shape. The upper end portion 9Ba of the second dustproof net 9B is fixed to the additional bracket 19a, the lower end portion 9Bb of the second dustproof net 9B is fixed to the additional bracket 19b, and the additional bracket 19a is fixed to the bracket 18a by the bolt stopper 20a. 19b is fixed to the bracket 18b by a support structure member 20b.

  Also in this embodiment, the second dust-proof net 9B is provided in the range corresponding to the cooling flow path to the radiator 11 which is the upstream side of the cooling air of the first dust-proof net 8 and has the lowest ventilation resistance. In addition, since the second dust-proof net 9B has ventilation resistance, the first effect of the first embodiment can be obtained.

  The second dust-proof net 9B does not have the second dust-proof net side surface portion 9d of the first embodiment, but even when clogging occurs in the second dust-proof net main surface portion 9Bc, the cooling air flows through the opening portion 7. The radiator 11 can be cooled, and the cooling performance of the radiator 11 can be maintained. That is, the same effect as the second effect of the first embodiment can be obtained.

  In addition, the dustproof device of this embodiment adds the 2nd dustproof net 9B and the additional bracket 19 to the structure of the conventional dustproof device, and can obtain the 3rd effect of 1st Embodiment.

<Fourth embodiment>
FIG. 10 is a cross-sectional view of the dustproof device of the fourth embodiment. The fourth embodiment is a modification of the third embodiment. The additional bracket 19 of the third embodiment has a substantially Ω-shape, whereas the additional bracket 19C of the fourth embodiment has a flat bar shape. Accordingly, there is no configuration corresponding to the opening 7 of the third embodiment, and the first dustproof net 8 and the second dustproof net 9C are close to each other.

  Also in this embodiment, the second dust-proof net 9C is provided in the range corresponding to the cooling flow path to the radiator 11 which is the upstream side of the first dust-proof net 8 and is the heat exchanger having the lowest ventilation resistance. And since the 2nd dustproof net 9C serves as ventilation resistance, the 1st effect of a 1st embodiment is acquired.

  Moreover, the dustproof device of this embodiment adds the 2nd dustproof net 9C and the additional bracket 19C to the structure of the conventional dustproof device, and can obtain the 3rd effect of 1st Embodiment. However, the second effect of the first embodiment cannot be obtained.

<Fifth Embodiment>
In the first to fourth embodiments, for convenience of explanation, the radiator 11 among the heat exchangers 11 to 13 is the heat exchanger having the lowest ventilation resistance, but may be changed as appropriate for convenience of design. For example, the oil cooler 12 may be a heat exchanger with the lowest ventilation resistance. In this case, in the conventional dustproof device, the dust is concentrated and accumulated in a range facing the oil cooler 12 of the dustproof net 8.

  FIG. 11 is a cross-sectional view of the dustproof device of the fifth embodiment. In the present embodiment, the same second dust net 9D as the second dust net 9 of the first embodiment is provided in a range corresponding to a cooling flow path to the oil cooler 12, which is a heat exchanger having the lowest ventilation resistance. is there.

  The characteristic configuration which is the essence of the present embodiment is the same as the configuration of the first embodiment, and the first to third effects of the first embodiment can be obtained.

<Sixth Embodiment>
FIG. 12 is a cross-sectional view of the dustproof device of the sixth embodiment. This embodiment is a modification of the second embodiment when the oil cooler 12 is a heat exchanger having the lowest ventilation resistance.

  The second dustproof net 9E is inclined so as to approach the cooling air downstream side from the oil cooler 12 side having the lowest ventilation resistance toward the adjacent radiator 11 side. The additional bracket 19E has a substantially square shape corresponding to the inclination of the second dustproof net 9E.

  Also in the present embodiment, the second dust-proof net 9E is provided in the range corresponding to the cooling flow path to the oil cooler 12, which is the heat exchanger upstream of the first dust-proof net 8 and has the lowest ventilation resistance. In addition, since the second dust-proof net 9E provides ventilation resistance, the first effect of the first embodiment can be obtained.

  A part of the dust deposited on the second dustproof net 9E is urged along the inclination by the cooling air, moves toward the radiator 11, and is dispersed and accumulated on the dustproof net 8. That is, the first effect can be improved.

  In addition, the dustproof device of this embodiment adds the 2nd dustproof net 9E and the additional bracket 19E to the structure of the conventional dustproof device, and can obtain the 3rd effect of 1st Embodiment.

<Seventh embodiment>
In the first to sixth embodiments, for convenience of explanation, in the heat exchanger unit 10, the intercooler 13, the radiator 11, and the oil cooler 12 are arranged in parallel from the right when viewed from the cooling air upstream side. However, it is changed as appropriate for design reasons. For example, the radiator 11, which is a heat exchanger with the lowest ventilation resistance, may be arranged on the left side when viewed from the upstream side of the cooling air. In this case, in the conventional dustproof device, dust is concentrated and accumulated in a range facing the radiator 11 of the dustproof net 8 on the left side when viewed from the upstream side of the cooling air.

  FIG. 13 is a cross-sectional view of the dustproof device of the seventh embodiment. In the present embodiment, the same second dust net 9F as the second dust net 9 of the first embodiment is provided in a range corresponding to a cooling flow path to the radiator 11, which is a heat exchanger having the lowest ventilation resistance. .

  The characteristic configuration which is the essence of the present embodiment is the same as the configuration of the first embodiment, and the first to third effects of the first embodiment can be obtained.

DESCRIPTION OF SYMBOLS 1 Engine chamber 2 Engine 3 Cooling fan 4 Shroud 7 Opening 8 1st dust net 9, 9A-F 2nd dust net 10 Heat exchanger unit 11 Radiator 12 Oil cooler 13 Intercooler 14 Fuel cooler 15 Capacitor 16 Battery 17a Upper frame 17b Lower frame 18a, 18b Bracket 19a, 19b Additional bracket 20a, 20c, 20d Bolt stop 20b Supporting structural member 21, 22, 23, 24 Opening 27 Building cover 31 Crank pulley
32 Fan pulley
33 Fan Belt
34 Auxiliary rotating shaft 35 Engine crankshaft 101 Hydraulic excavator 102 Lower traveling body
113 Upper swing body
104 frame 105 cabin
106 Counterweight 110 Front attachment 111 Boom 112 Boom cylinder 113 Arm 114 Arm cylinder
115 buckets
116 bucket cylinder

Claims (5)

The cooling device for cooling the heat exchanger unit composed of a plurality of heat exchangers arranged in parallel by the cooling air induced by the cooling fan and taken in from the opening is provided on the upstream side of the cooling air of the heat exchanger unit. In a dustproof device for a construction machine provided with a first dustproof net provided opposite to the heat exchanger unit and capturing dust in cooling air,
In the range corresponding to the cooling flow path to the heat exchanger having the lowest ventilation resistance among the plurality of heat exchangers on the cooling air upstream side of the first dustproof net, facing the first dustproof net. A dustproof device for a construction machine, comprising a second dustproof net provided. The dustproof device for a construction machine according to claim 1,
The second dust-proof net has a main surface portion facing the first dust-proof net and a side surface portion protruding from the main surface portion to the cooling air downstream side. The dustproof device for a construction machine according to claim 1,
The second dustproof net is inclined so as to approach the cooling air downstream side from the heat exchanger side having the lowest ventilation resistance toward the heat exchanger side adjacent to the heat exchanger having the lowest ventilation resistance. A dustproof device for construction machinery. The dustproof device for a construction machine according to claim 3,
The heat exchanger with the lowest ventilation resistance is adjacent to other heat exchangers on both sides,
The second dustproof net has a mountain shape in which the first surface and the second surface are in contact with each other by a ridgeline,
The first surface of the second dustproof net is inclined so as to approach the cooling air downstream side from the heat exchanger side having the lowest ventilation resistance toward one heat exchanger side adjacent thereto,
The second surface of the second dustproof net is inclined so as to approach the cooling air downstream side from the heat exchanger side having the lowest ventilation resistance toward the other heat exchanger side adjacent thereto. Dustproof device for construction machinery. The dustproof device for a construction machine according to claim 1,
The second dustproof net is added to the existing first dustproof net. A dustproof device for a construction machine.

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