JP4384776B2 - Engine room cooling structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cooling structure for an engine room of a hydraulic excavator, and more particularly to a cooling structure for an engine room in which the amount of cooling air is increased.
[0002]
[Prior art]
In a small turning type hydraulic excavator, in order to reduce the turning radius, it is important to arrange a lot of equipment on the upper turning body, and also to ensure the amount of cooling air in the engine room with the set arrangement. This is an important issue. An example of an engine room of a conventional small turning hydraulic excavator will be described with reference to FIGS. FIG. 7 is a side view of a conventional small swivel excavator, and FIG. 8 is a cross-sectional view taken along the line CC in FIG. As shown in FIGS. 7 and 8, the small turning excavator 10 </ b> A includes an upper turning body 32 that is turnable on an upper portion of the lower traveling body 1. On the upper surface of the revo frame 33 of the upper revolving structure 32, a cab 34 is located at the front of one side in the left-right direction of the vehicle, a fuel tank 38 is located behind the cab 34, a hydraulic oil tank 37 is located at the other side in the left-right direction. A counterweight 36 is provided. An engine room 35 is formed in a space surrounded by the cab 34, fuel tank 38, hydraulic oil tank 37, counterweight 36, and the like. In the engine room 35, an engine 11, a radiator 12, a cooling fan 13, an oil cooler 18, and the like are housed.
[0003]
As shown in FIG. 8, the cooling air sucked by the cooling fan 13 and cooling the radiator 12, the oil cooler 18, and the like is formed between the engine 11 and the fuel tank 38 and between the engine 11 and the counterweight 36. Flows in the direction of the arrow through the passage. The engine 11, the fuel tank 38, the hydraulic oil tank 37, the hydraulic pump 9 and the like are discharged to the outside while cooling.
[0004]
[Problems to be solved by the invention]
However, the above prior art has the following problems. Since the cooling air passage on the side of the engine 11 (that is, in the vehicle longitudinal direction) is narrow, the flow resistance is large, and the amount of cooling air sucked by the cooling fan 13 is reduced. For this reason, it is necessary to increase the size of the cooling fan 13 or to set the engine speed to a higher value, which causes problems that cooling efficiency is reduced, fuel consumption is reduced, and noise is high.
[0005]
By the way, as a prior art for reducing the flow resistance of cooling air in the engine room of a construction machine, there is one disclosed in, for example, Japanese Patent Laid-Open No. 11-82015, and FIG. 9 shows an engine described in the same publication. It is a side view which shows the apparatus arrangement configuration in a room. In the figure, the engine 51 is placed on tail frames 59A and 59B provided at the lower part in the engine room. Further, the lower cover 56 of the engine room located below the engine 51 is formed with a convex part 58 projecting outward from the engine room, and the convex part 58 has a wider range than the interval between the tail frames 59A and 59B. It is formed to span. Thus, even if the tail frames 59A and 59B are present, the flow path 58F is formed by the convex portion 58, so that the cooling air sucked by the cooling fan 52 passes through the flow path 58F and passes through the oil pan 51a of the engine 51. It is said to be cooled efficiently and discharged outside the engine room.
[0006]
However, in the technique disclosed in Japanese Patent Application Laid-Open No. 11-82015, since the convex portion 58 is formed on the lower cover 56, the convex portion 58 may come into contact with an obstacle during turning and may be damaged. is there. Further, since the small swing hydraulic excavator described above has a narrow gap between the lower cover lower surface of the engine room 35 and the upper surface of the crawler belt of the lower traveling body 1, the lower cover of the engine room 35 depending on the work situation when the above technique is applied. The lower surface and the lower traveling body 1 may interfere with each other, and this application is difficult.
[0007]
An object of the present invention is to provide a cooling structure for an engine room that can increase the amount of cooling air without causing the engine room to protrude outward from the vehicle body, focusing on the above-mentioned conventional problems.
[0008]
[Means for solving the problems and effects]
In order to achieve the above-described object, the present invention provides a hydraulic system in which an engine room is provided at the rear of a cab disposed on the front part on the left and right sides of the upper swing body, and the engine, radiator and cooling fan are accommodated in the engine room. In the cooling structure of the engine room of the excavator, a space portion is provided at the rear of the rear wall by forming the lower portion of the rear wall of the cab toward the inside of the cab, and the engine and the radiator are disposed at the rear portion of the lower portion of the rear wall. remote disposed behind has a structure in which the space and the passage of the cooling air of the cooling fan. According to the above configuration, the lower portion of the rear wall of the cab is formed so as to enter inside using the space behind the operator seat in the cab, thereby providing a space portion having a predetermined gap behind the rear wall. The space is used as a cooling air passage by a cooling fan. Therefore, the passage area of the cooling air can be increased without causing the engine room to protrude outward from the vehicle body and without sacrificing the comfort in the cabin. As a result, the cooling air volume can be increased and the cooling efficiency can be improved, so that the fuel consumption can be improved and the noise can be reduced.
[0009]
In the present invention, it is preferable that a partition plate for preventing the return of cooling air to the intake side of the radiator is provided in the space provided behind the lower portion of the rear wall of the cab. According to this configuration, the partition plate provided in the space behind the rear wall of the cab prevents the cooling air from returning to the intake side of the radiator via the space, that is, recirculation of the cooling air. Therefore, the cooling air can be used effectively. Therefore, it is possible to improve the cooling efficiency, improve fuel efficiency and reduce noise.
[0010]
Further, a through hole may be provided in the partition plate, and a pipe of a hydraulic device such as an oil cooler housed in the engine room may be passed through the hole. According to this configuration, since the piping of hydraulic equipment such as an oil cooler is passed through the partition plate, these piping are cooled by the cooling air flowing through the space (passage) provided behind the lower rear wall of the cab. The cooling efficiency of hydraulic equipment can be improved. Further, by using the space portion, the piping can be laid with a small number of bent portions without being greatly affected by the arrangement of other devices, thereby facilitating the laying.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments will be described below with reference to FIGS. 1 to 6. Note that the same components as those in FIGS. 7 and 8 are denoted by the same reference numerals and description thereof is omitted. First, a small turning hydraulic excavator 10 to which a cooling structure for an engine room according to the present invention is applied will be described with reference to FIGS. FIG. 1 is a side view of a small swing type hydraulic excavator 10, and FIG. 2 is a cross-sectional view taken along line AA of FIG. The revo frame 3 provided at the lower end of the upper swing body 2 is provided with a cabin 4 on the left and right front, a hydraulic oil tank 7 and a fuel tank 8 on the left and right sides, and a rear end. A counterweight 6 is mounted. In addition, a work machine 30 including a boom 25 and the like is pivotally supported at the front center of the revo frame 3 so as to be swingable. The engine room 5 is surrounded by a cab 4, a counterweight 6, a hydraulic oil tank 7, a fuel tank 8, and the like, and an upper surface is covered by an upper cover 5a. Inside the engine room 5, an engine 11, a radiator 12, a cooling fan 13, a hydraulic pump 9, an oil cooler 18, and the like are housed.
[0012]
As will be described in detail later, the lower portion of the rear wall 4a of the cab 4 is inserted into the inside of the cab 4, and a space portion with a predetermined gap is provided behind the lower portion of the rear wall 4a. The engine 11 is disposed at a substantially central position between the cab rear wall 4a and the counterweight 6. At this time, the engine room 5 is widened by an amount corresponding to the newly provided space portion, and is formed between the passage R <b> 1 formed between the cab 4 and the engine 11, and between the counterweight 6 and the engine 11. The passage width of the passage R2 is wider than before. Further, a partition plate 15 for preventing backflow is provided between the rear wall 4 a and the radiator 12. The partition plate 15 is made of a hard material such as iron or hard resin.
[0013]
Next, the cooling air passage R1 behind the cab 4 will be described with reference to FIGS. 3 is an explanatory view of the passage R1 behind the cab 4 and the partition plate 15, FIG. 4 is a sectional view taken along the line BB of FIG. 3, and FIG. 5 is an explanatory view of the piping of the partition plate 15. As shown in FIG. 3, the lower part of the rear wall 4 a of the cab 4 is formed so as to enter the space behind the operator seat 4 b in the cab 4. A passage R <b> 1 is secured in the space between the rear wall 4 a that enters the inside of the cab 4 and the engine 11. In addition, a partition plate 15 is provided between the lower portion of the rear wall 4a of the cab 4 and the side surface of the radiator 12 to prevent the cooling air from flowing backward to the outside air intake side of the radiator 12 via the passage R1. The partition plate 15 is attached to the side surface of the radiator 12 by bolts 16, and a seal member 17 is provided between the lower portion of the rear wall 4a and the partition plate 15 to prevent cooling air from leaking.
[0014]
Further, the partition plate 15 is provided with a plurality of holes for piping. As shown in FIG. 5, the plurality of holes of the partition wall plate 15 have pipes 18 a, 18 a, such as an oil cooler 18, an aftercooler 19, a condenser 20, and an air cleaner 21 disposed on the outside air intake side of the radiator 12. 19a, 20a, and 21a are pierced and laid, and are connected to the respective connected devices via the passage R1.
[0015]
Next, the operation of the present embodiment will be described with reference to FIGS. FIG. 6 is a diagram showing the flow of cooling air in the engine room 5. As shown in FIG. 6, the cooling air sucked from the inlet S formed in the upper cover (not shown) of the engine room 5 by the cooling fan 13 cools the oil cooler 18, the radiator 12, and the like, and then the rear of the cab 4. It flows through the passage R1 behind the wall 4a in the direction of the arrow. Then, the engine 11, the hydraulic oil tank 7, the fuel tank 8, the hydraulic pump 9, and the like are cooled and discharged to the outside from the exhaust ports E1, E2, and E3 through the three routes a, b, and c, respectively. Similarly, the cooling air is discharged to the outside from the exhaust ports E1 and E2 via the passage R2. The exhaust port E1 and the exhaust ports E2 and E3 are formed in, for example, a right side cover and an upper cover (not shown) of the engine room 5, for example.
[0016]
Here, the gap between the passages R1 and R2 is larger than the conventional space by the space newly provided behind the recessed portion of the rear wall 4a of the cab 4, so that the flow path resistance is reduced and the cooling air volume is increased. To do. Therefore, the engine room 5 is not protruded outward as in the conventional convex portion 58 described in the section of the problem, for example, and without sacrificing the comfortability in the cab 4, the cooling air passage R1. , R2 can be sufficiently secured to increase the air volume. As a result, the cooling efficiency can be improved, fuel efficiency can be improved, and noise can be reduced.
[0017]
In addition, the partition plate 15 provided in the space between the side surface of the radiator 12 and the rear wall 4a of the cab 4 is made of a hard material, so that it is not deformed by heat or the like. The plate 15 is reliably blocked and does not flow backward to the intake side of the radiator 12. Thereby, the recirculation of the cooling air passing through the space portion behind the cab 4 can be prevented, and the cooling efficiency can be improved. In the above-described embodiment, the example of the cooling method in which the air is sucked from the front of the cooling fan, blown into the engine room behind the fan, and discharged is described. However, the present invention is not limited to this. It may be applied to a method in which the air is sucked by a cooling fan via the air and discharged from the front of the fan to the outside.
[0018]
Also, the partition plate 15 is provided with holes for hydraulic piping as shown in FIG. 3, and as shown in FIG. 5, piping for equipment such as an oil cooler 18, an aftercooler 19, a condenser 20 and an air cleaner 21 on the intake side of the radiator 12. Since 18a, 19a, 20a, and 21a are laid through the holes, the penetrated pipes are exposed in the cooling air passage R1 and are forcibly cooled by the cooling air. Thereby, cooling efficiency can be improved. Moreover, since piping is laid using the inside of the said space part behind the cab 4 provided widely, it can lay easily.
[0019]
As described above, the present invention has the following effects. The lower part of the cab's rear wall is shaped so as to enter the inside, and a space is provided behind the cab, and this space is used as a cooling air passage. It is possible to sufficiently secure the cooling air volume without sacrificing the above. Therefore, it is possible to improve the cooling efficiency, reduce the size of the radiator, and reduce noise by reducing the engine speed. Further, since the partition plate is provided between the side surface of the radiator and the rear wall of the cab, recirculation of the cooling air can be prevented and the cooling air can be used effectively. Therefore, the equipment and piping in the engine room can be efficiently cooled. Furthermore, since the pipes are passed through the holes in the partition plate, it is easy to lay pipes such as an oil cooler disposed on the intake side of the radiator, and the pipes are efficiently cooled by cooling in the cooling air passages. it can.
[Brief description of the drawings]
FIG. 1 is a side view of an applicator for an engine room cooling structure according to the present invention.
FIG. 2 is a cross-sectional view taken along the line AA of FIG.
FIG. 3 is an explanatory diagram of a passage behind a cab and a partition plate.
4 is a cross-sectional view taken along the line BB in FIG.
FIG. 5 is an explanatory diagram of piping of a partition plate.
FIG. 6 is a diagram showing a flow of cooling air in an engine room.
FIG. 7 is a side view of a conventional small turning hydraulic excavator.
8 is a cross-sectional view taken along the line CC of FIG.
FIG. 9 is a side view of another prior art engine room.
[Explanation of symbols]
1 ... Lower traveling body, 2 ... Upper revolving body, 3 ... Revo frame, 4 ... Cab, 5 ... Engine room, 6 ... Counterweight, 7 ... Hydraulic oil tank , 8 ... Fuel tank, 9 ... Hydraulic pump, 10 ... Small swivel excavator, 11 ... Engine, 12 ... Radiator, 13 ... Cooling fan, 15 ... Bulkhead plate , 16 ... Bolt, 17 ... Sealing material, 18 ... Oil cooler, 19 ... After cooler, 20 ... Condenser, 21 ... Air cleaner, 25 ... Boom, 30 ... Work Machine.

Claims (4)

An engine room (5) is provided behind the cab (4) disposed on the left and right front portions of the upper swing body (2), and the engine (11), the radiator (12) and the engine room (5) are provided in the engine room (5). In the cooling structure of the engine room of a hydraulic excavator that houses the cooling fan (13), the rear wall (4a) is formed in a shape in which the lower part of the rear wall (4a) of the cab (4) is entered toward the inside of the cab (4). ) A space is provided at the rear, and the engine (11) and the radiator (12) are arranged behind the space at the lower rear of the rear wall (4a), and the space is cooled by the cooling fan (13). Engine room cooling structure characterized by a passage (R1).   2. A cooling structure for an engine room according to claim 1, wherein a partition wall for preventing cooling air from returning to the intake side of the radiator (12) is provided in the space provided at the rear of the lower portion of the rear wall (4a) of the cab (4). Engine room cooling structure characterized by a plate (15).   3. A cooling structure for an engine room according to claim 2, wherein a through hole is provided in the partition plate (15), and a pipe for a hydraulic device such as an oil cooler (18) housed in the engine room (5) is provided in the hole (18a- Engine room cooling structure characterized by passing through 21a). The engine room cooling structure according to claim 2,
The partition wall plate (15) is formed from the side surface of the radiator (12) along the rear wall (4) of the cab (4) along the shape in which the lower part of the rear wall (4a) of the cab (4) is inserted toward the inside of the cab (4). 4a) Engine room cooling structure characterized in that the upper side is inclined toward the bottom.

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