JP6717265B2 - Construction machinery - Google Patents

Description

The present invention relates to a construction machine.

Construction machines such as cranes and hydraulic excavators generally include an internal combustion engine as a power source. The internal combustion engine is housed in an engine guard (casing). In addition, the internal combustion engine has a heat exchanger (radiator) that cools the cooling water and a fan that sucks air to pass through the heat exchanger in order to cool the cylinder block with the cooling water. For this reason, the engine guard is provided with an opening for taking in the air passing through the heat exchanger. In such a construction machine, noise caused by the sound of the fan leaking through the opening of the engine guard is regarded as a problem.

Many fan improvements have been proposed to reduce such noise. As an example, Japanese Patent Laid-Open No. 2006-226200 has a structure of a mixed flow fan inside a cylindrical boss portion as a fan that sucks air so as to pass through a heat exchanger, and is provided outside the boss portion. A fan having a structure of an axial fan (propeller fan) has been proposed. However, it is difficult to sufficiently reduce the noise only by improving the fan.

For this reason, we also adopted a method to reduce noise by installing a louver with multiple strips arranged parallel to each other in the opening of the engine guard and tilted in side view to prevent the fan sound from passing through the opening straight. Has been done. However, when the louver is provided, the flow passage resistance increases and the amount of air passing through the heat exchanger decreases, so that a fan with a higher output is required, and as a result, noise may not be sufficiently reduced.

JP, 2006-226200, A

In view of the above situation, it is an object of the present invention to provide a construction machine with low engine noise.

The construction machine according to the present invention made to solve the above problems includes a heat exchanger and an engine having a fan that sucks air through the heat exchanger, an engine guard that covers an upstream side of the heat exchanger, and A sound absorbing material is provided so as to penetrate the engine guard so as to provide an air flow path for supplying outside air to the heat exchanger, has a protruding length to the outside and the inside of the engine guard, and has at least a part of an inner surface thereof. And a suction duct arranged.

Since the construction machine is provided with the suction duct in the engine guard, the construction machine can suck outside air and supply it to the heat exchanger with a relatively small air resistance. Further, since the sound absorbing material is arranged inside the suction duct, it is possible to absorb the sound of the fan and reduce the noise. Further, in the construction machine, since the ducts project inside and outside the engine guard, it is possible to secure the length of the suction duct and increase the sound absorbing area. Further, by increasing the length of the suction duct, the angle region in which the engine, which is the sound source, can be directly viewed through the suction duct from the outside is reduced, so that the sound absorbing effect of the sound absorbing material can be improved. Here, since the sound absorbing material is arranged on the inner surface of the suction duct, the area of the air flow path does not become small even if the area is increased. For this reason, in the construction machine, the sound of the fan can be relatively efficiently absorbed by the sound absorbing material, so that the noise of the engine observed outside the engine guard is small.

In the construction machine, the suction duct may extend substantially horizontally, and an upper protruding length of the suction duct outward from the engine guard may be larger than a lower protruding length of the lower portion from the engine guard. According to this configuration, it is possible to prevent rainwater and the like from entering the suction duct due to the upper portion of the suction duct (upper part of the peripheral wall) serving as an eaves. Note that “substantially horizontal” means that the angle of inclination with respect to the horizontal is 5° or less.

In the construction machine, the upper surface of the protruding portion of the suction duct from the engine guard may also serve as a step for moving up and down. According to this structure, the projecting portion of the suction duct can be effectively used, and the opening area of the suction duct can be increased.

In the construction machine, it is preferable that the suction duct does not exist on the rotation axis of the fan. With this configuration, it is possible to prevent the sound wave emitted from the fan from passing straight through the suction duct, and to promote the absorption of the sound wave by the sound absorbing material.

In the construction machine, the inside of the suction duct may be divided into a plurality of parts. With this configuration, it is possible to more reliably suppress the sound wave from passing through the suction duct.

In the construction machine, an opening may be provided in a part of the suction duct located inside the engine guard. According to this configuration, by providing the opening in the suction duct, the air introduced from the suction duct can be efficiently diffused into the engine guard, and the air can be relatively evenly supplied to the entire heat exchanger. You can

A sound absorbing material may be arranged on at least a part of an outer surface of the suction duct, which is located inside the engine guard. According to this configuration, since the sound wave reflected inside the engine guard can be absorbed, the noise can be further reduced.

In the construction machine, the sound absorbing material may not be arranged at the bottom of the inner surface of the suction duct. With this configuration, liquid such as rainwater that has entered the suction duct can be easily discharged.

As described above, the construction machine according to the present invention has low engine noise.

It is a typical side view showing the construction machine of one embodiment of the present invention. It is a schematic diagram which shows the structure of the engine vicinity of the construction machine of FIG. FIG. 3 is a schematic perspective view of the engine guard of FIG. 2. FIG. 3 is a schematic cross-sectional view of a suction duct provided in the engine guard of FIG. 2 in a flow path direction. 5 is a schematic cross-sectional view of the suction duct of FIG. 4 in a direction perpendicular to the flow path.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

[Construction machinery]
FIG. 1 shows a construction machine according to an embodiment of the present invention. The construction machine is a crawler crane.

The construction machine includes a self-propelled lower traveling body 1 and an upper revolving body 2 provided on the lower traveling body 1 so as to be horizontally rotatable.

The lower traveling body 1 has a pair of crawlers 3 as a traveling device.

A crane attachment (work implement) 4 is tiltably attached to the front of the upper swing body 2. The upper revolving structure 2 includes an engine 5, a hydraulic pump 6 driven by the engine 5, an engine guard 7 that covers the engine 5 and the hydraulic pump 6, and a plurality of units arranged so as to penetrate the engine guard 7. And the suction duct 8 of.

The construction machine is configured to drive the turning of the upper revolving structure 2, the rotation of the crawler 3, the tilting of the crane attachment 4 and the hoisting of the rope by the hydraulic oil supplied from the hydraulic pump 6.

<Engine>
As shown in FIG. 2, the engine 5 includes an engine body 9 including an internal combustion engine, a heat exchanger (radiator) 10 that lowers the temperature of cooling water that cools the engine body 9, and an air through the heat exchanger 10. And a fan 11 for sucking.

The engine body 9 may be, for example, a reciprocating engine that combusts fuel in a cylinder to reciprocate a piston, such as a diesel engine. Such a reciprocating engine may be of a direct injection type in which fuel is directly sprayed into the cylinder, or may have a supercharger such as a turbocharger which compresses air and supplies the compressed air into the cylinder.

The heat exchanger 10 has a large number of thin tubes having fins, and can have a well-known configuration for exchanging heat between the cooling water flowing in the thin tubes and the outside air. The heat exchanger 10 may be configured by arranging a plurality of heat exchange units.

As the fan 11, for example, an axial fan, a diagonal fan, or the like can be used.

The engine 5 preferably has a guide duct 12 connecting the heat exchanger 10 and the fan 11 so that the fan 11 sucks only the air passing through the heat exchanger 10.

<Engine guard>
As shown in FIG. 3, the engine guard 7 is provided so as to cover at least the upstream side of the heat exchanger 10, and surrounds the engine 5 alone or integrally with other components, so that the sound generated by the engine 5 is generated. Absorbs.

Further, the engine guard 7 preferably has sufficient strength so that an operator can climb on the engine guard 7 and use it as a scaffold for attaching and detaching the crane attachment 4, disassembling and assembling, and maintaining the crane attachment 4.

Further, the engine guard 7 preferably has a door that can be opened in a portion that covers the side of the engine 5 in order to facilitate maintenance of the engine 5.

The engine guard 7 can be formed of, for example, a plated steel plate, a stainless steel plate, or the like. Further, the engine guard 7 preferably has a sound absorbing material on its inner surface in order to absorb the sound of the engine 5. As the sound absorbing material provided on the inner surface of the engine guard 7, for example, urethane foam on a sheet or a plate can be used.

<Suction duct>
The suction duct 8 is arranged on the upstream side of the heat exchanger 10 so as to penetrate the engine guard 7. The suction duct 8 is preferably arranged so as to extend in a substantially horizontal direction. By thus extending the suction duct 8 in a substantially horizontal direction, it is possible to allow the outside air to flow into the inside of the engine guard 7 in a horizontal direction, and the fan 11 is arranged so that its rotation axis is horizontal, and the upstream side of the fan 11 is Air can be efficiently supplied to the heat exchanger 10 installed vertically in the vertical direction. Such arrangement of the heat exchanger 10 and the fan 11 can easily improve the space efficiency and also improve the maintainability.

Further, it is preferable that the suction duct 8 is arranged so as not to exist on the rotation axis of the fan 11. In this way, by providing the suction duct 8 offset with respect to the rotation axis of the fan 11, it is possible to prevent the sound waves emitted from the fan 11 from passing straight through the suction duct 8 and leaking to the outside.

As shown in FIGS. 4 and 5, the suction duct 8 includes an outer wall 13 having a rectangular tubular shape, a plurality of partition walls 14 provided upright so as to divide the inside of the outer wall 13 into a plurality of parts in the horizontal direction, and an outer wall 13. Other than the bottom of the inner surface (top surface and both side surfaces) and the sound absorbing material 15 arranged on both surfaces of the partition wall 14. Further, the suction duct 8 further includes a mesh body 16 that prevents foreign matter from entering and a flange 17 that is fixed to the engine guard 7.

Since the inside of the suction duct 8 is divided into a plurality of air passages that are horizontally aligned by a plurality of partition walls 14, the angle range where the inside of the suction duct 8 can be seen from the outside becomes small, and The sound wave emitted from 11 hits the sound absorbing material 15 provided on the surface of the partition wall 14 and is easily absorbed.

The spacing between the plurality of partition walls 14 is preferably substantially equal to the spacing between the upper wall and the lower wall of the outer wall 13. That is, it is preferable that the cross-sectional shapes of the plurality of air flow paths formed in the suction duct 8 are substantially square. Specifically, the ratio of the spacing between the plurality of partition walls 14 to the spacing between the upper wall and the lower wall of the outer wall 13 is preferably 0.8 or more and 1.2 or less, for example. Thereby, the horizontal component and the vertical component of the sound wave emitted from the fan 11 can be absorbed substantially equally.

Further, since the sound absorbing material 15 is not arranged at the bottom of the inner surface of the suction duct 8, rainwater or the like that has entered the suction duct 8 is easily discharged.

The suction duct 8 has a protruding length outward from the engine guard 7 at the upper portion (upper wall) of the outer wall 13 is longer than a protruding length outward from the engine guard 7 at the lower portion (lower wall). As a result, the upper portion of the suction duct 8 serves as an eaves and rainwater and the like can be prevented from entering the suction duct 8.

Further, the upper surface of the projecting portion of the suction duct 8 from the engine guard 7 can also serve as a step for the operator to move up and down. In this way, by effectively utilizing the projecting portion of the suction duct 8 as a step, the opening area of the suction duct 8 can be increased and the number of parts can be reduced.

Further, the suction duct 8 may have an opening on the inner wall of the engine guard 7. By forming the opening in the wall of the suction duct 8 in this way, the air introduced through the suction duct 8 can be easily diffused into the engine guard 7, so that the air can be supplied more uniformly to the entire heat exchanger 10. can do.

The opening of the wall of the suction duct 8 is preferably formed in a wall near the outer edge of the fan 11 when viewed in the rotation axis direction of the fan 11. Since the flow velocity of the air sucked at the outer edge of the fan 11 is high, the diffusion effect of the air can be further improved by forming the opening in the wall near the outer edge of the fan 11.

The construction machine shown in the drawing has not only the step formed by the protruding portion of the suction duct 8 but also an independent step that is not shared with the suction duct 8 between the steps formed by the suction duct 8. The construction machine may also have a handrail that the operator can use to climb the engine guard 7 using these steps.

The total flow passage cross-sectional area of the plurality of suction ducts 8 can be, for example, 10% or more and 25% or less of the projected area of the effective portion of the heat exchanger 10. If the total flow passage cross-sectional area of the plurality of suction ducts 8 is less than the above lower limit, the engine body 9 may not be cooled sufficiently. On the contrary, when the total flow passage cross-sectional area of the plurality of suction ducts 8 exceeds the above upper limit, the amount of sound waves emitted from the engine guard 7 may not be sufficiently suppressed.

The width of the suction duct 8 in the direction vertical and horizontal to the flow path direction may be, for example, 50 cm or more and 100 cm or less. When the width of the suction duct 8 is less than the above lower limit, it is difficult to increase the flow passage area. On the other hand, if the width of the suction duct 8 exceeds the above upper limit, the engine guard 7 may unnecessarily increase in size.

The height of the suction duct 8 in the direction perpendicular to the flow path direction and the vertical direction may be, for example, 10 cm or more and 30 cm or less. If the height of the suction duct 8 is less than the above lower limit, it is difficult to increase the flow passage area. On the contrary, if the height of the suction duct 8 exceeds the upper limit, rainwater or the like may easily enter the suction duct 8.

The length in the flow path direction of the region where the wall exists on the entire circumference of the suction duct 8 can be, for example, 20 cm or more and 80 cm or less. If the length of the suction duct 8 is less than the above lower limit, the sound generated by the fan 11 may not be sufficiently absorbed. On the contrary, if the length of the suction duct 8 exceeds the upper limit, the engine guard 7 may unnecessarily increase in size.

The outer wall 13 can be formed of, for example, a plated steel plate, a stainless steel plate, or the like.

The plate thickness of the outer wall 13 can be, for example, 0.8 mm or more and 3.2 mm or less. If the plate thickness of the outer wall 13 is less than the above lower limit, the strength of the suction duct 8 may be insufficient, or the suction duct 8 may vibrate to generate another noise. On the contrary, when the plate thickness of the outer wall 13 exceeds the above upper limit, the formation cost of the suction duct 8 may unnecessarily increase.

The inner end portion of the engine guard 7 on the bottom wall of the outer wall 13 is folded back upward to prevent rainwater and the like that have entered the suction duct 8 from falling inside the engine guard 7, and to prevent the engine guard 7 from the suction duct 8. May be discharged to the outside.

The outer end of the outer wall 13, in particular, the tip of the upper wall may be bent inward to form a rib for improving strength.

The partition wall 14 can be provided in a portion where the outer wall 13 inside the net body 16 exists over the entire circumference.

The partition wall 14 can be formed of, for example, a plated steel plate, a stainless steel plate, or the like, and may be formed of a plate (for example, punching metal or the like) provided with one or a plurality of openings sealed by the sound absorbing material 15. .. In other words, it suffices that the partition wall 14 cooperate with the sound absorbing material 15 to divide the internal space of the suction duct 8.

As the sound absorbing material 15, for example, a sheet-shaped or plate-shaped urethane foam or the like can be used and may be attached to the outer wall 13 and the partition wall 14 with an adhesive or the like. The average thickness of the sound absorbing material 15 can be, for example, 10 mm or more and 45 mm or less. When the average thickness of the sound absorbing material 15 is less than the above lower limit, sound absorption may be insufficient. On the contrary, when the average thickness of the sound absorbing material 15 exceeds the upper limit, the cross-sectional area of the air flow path may be unnecessarily reduced.

The sound absorbing material 15 can also be arranged on the outer surface of the outer wall 13 inside the engine guard 7 in order to improve the sound absorbing effect.

The mesh 16 can be provided inside the outer wall 13 perpendicularly to the flow path direction. Further, by providing the net body 16 at a position retracted from the outer end of the outer wall 13, it is possible to prevent an operator from accidentally kicking and damaging the net body 16 when using the suction duct 8 as a step. ..

As the net body 16, for example, a wire mesh formed by combining a plurality of wires, a punching metal in which a plurality of openings are formed in a metal plate, or the like can be used. When a metal plate having a plurality of openings formed therein is used as the net body 16, the metal plate forming the outer wall 13 may be extended to form the net body 16.

The average mesh size of the mesh 16 can be, for example, 5 mm or more and 50 mm or less. If the average mesh size of the mesh 16 is less than the above lower limit, the aperture ratio may not be increased. On the contrary, when the average mesh size of the net body 16 exceeds the above and below, there is a possibility that the invasion of foreign matter cannot be prevented.

The aperture ratio of the net 16 may be, for example, 40% or more and 90% or less. If the opening ratio of the mesh 16 is less than the above lower limit, the suction resistance becomes large and the engine body 9 may not be sufficiently cooled. On the contrary, when the aperture ratio of the net body 16 exceeds the above upper limit, the strength of the net body 16 may be insufficient.

The flange 17 may be fixed so as to overlap the outer surface side of the engine guard 7. As a result, the suction duct 8 can be easily attached, and the sound absorbing material can be arranged on the inner surface of the engine guard 7 in the vicinity of the suction duct 8.

<Advantages>
In the construction machine, by providing the intake duct 8 on the engine guard 7 to form a flow path of air for cooling the heat exchanger 10, the sound wave emitted from the fan 11 is arranged on the inner surface of the intake duct 8. It is easily absorbed by the material 15. Therefore, in the construction machine, the sound of the fan 11 is difficult to be emitted to the outside of the engine guard 7, and the noise of the engine 5 is relatively small.

[Other Embodiments]
The above embodiment does not limit the configuration of the present invention. Therefore, in the above-mentioned embodiment, it is possible to omit, replace or add the constituent elements of each part of the above-mentioned embodiment based on the description and technical common sense of the present specification, and all of them are construed as belonging to the scope of the present invention. Should be.

In the construction machine, the sound absorbing material may be disposed on at least a part of the inner surface of the suction duct, and there may be a surface other than the bottom portion on which the sound absorbing material is not disposed. Further, in the construction machine, the sound absorbing material may be arranged on the bottom portion of the suction duct.

The construction machine is not limited to the crawler crane as in the embodiment, and may be, for example, a wheel crane or a hydraulic excavator.

The construction machine may be one that mechanically transmits and uses the rotation of the output shaft of the engine without hydraulic pressure, or one that drives a generator and converts it into electric power.

The construction machine may have an air flow path capable of introducing air into the engine guard other than the suction duct.

The construction machine according to the present invention can be particularly suitably used for a relatively large crane.

1 Lower Traveling Body 2 Upper Revolving Body 3 Crawler 4 Crane Attachment 5 Engine 6 Hydraulic Pump 7 Engine Guard 8 Suction Duct 9 Engine Body 10 Heat Exchanger 11 Fan 12 Guide Duct 13 Outer Wall 14 Partition Wall 15 Sound Absorbing Material 16 Net 17 Flange

Claims (7)

An engine having a heat exchanger and a fan sucking air through the heat exchanger;
An engine guard covering the upstream side of the heat exchanger,
The sound absorbing member is disposed so as to penetrate the engine guard so as to provide an air flow path for supplying outside air to the heat exchanger, has a protruding length to the outside and the inside of the engine guard, and has at least a part of an inner surface thereof. And a suction duct where
A guide duct connecting the heat exchanger and the fan,
While the suction duct and the rotation axis of the fan are arranged in the horizontal direction, the suction duct does not exist on the rotation axis of the fan,
The suction duct has an outer wall for forming the air flow path, and a flange for being fixed on the outer surface side of the engine guard,
A construction machine in which the suction duct includes a lower wall having an end bent upward inside the engine guard and an upper wall having an end bent downward outside the engine guard. .. With a plurality of the suction ducts ,
Construction machine of the protruding length from the engine guard of the upper portion to the outside, wherein the lower portion of the engine guard to claim 1 greater than the length of projection to the outside. The construction machine according to claim 1 or 2, which also serves as a step for ascending and descending an upper surface of a projecting portion of the suction duct from the engine guard. The construction machine according to claim 1 , wherein the inside of the suction duct is divided into a plurality of parts. The construction machine according to any one of claims 1 to 4 , wherein an opening is provided in a part of the suction duct located inside the engine guard. The construction machine according to any one of claims 1 to 5 , wherein a sound absorbing material is arranged on at least a part of an outer surface of the suction duct located inside the engine guard. The construction machine according to any one of claims 1 to 6 , wherein the sound absorbing material is not arranged at the bottom of the inner surface of the suction duct.

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