1. Field of the Invention
The present invention relates to an engine room for construction equipment, which can minimize emission of noise generated in an engine room of an excavator and so on to an outside of the engine room.
More particularly, the present invention relates to an engine room for construction equipment, which can minimize emission of noise generated in an engine room due to driving of an engine and a ventilating fan to an outside of the engine room by absorbing the noise through a noise trap, and can improve the cooling performance of corresponding components by smoothing inhalation/discharge of an external air to/from the airtight engine room.
2. Description of the Prior Art
Generally, in the case of performing a work using construction equipment such as an excavator and so on, noise generated from the construction equipment (e.g. an engine, a cooling fan, a hydraulic pump, and the like) has become influential as environmental problems, and its regulations have been gradually strengthened. Particularly, as technologies for low noise have been highlighted due to the strengthening of noise regulations in Europe, there is a need to minimize the noise emission from an engine room to an outside.
As illustrated in FIG. 1, a general excavator includes a lower driving structure 1; an upper swing structure 2 mounted to swing on the lower driving structure 1 in left or right direction; a cab 3 and an engine room 4 mounted on the upper swing structure 2; a working device 11 fixed to the upper swing structure 2, and composed of a boom 6 driven by a boom cylinder 5, an arm 8 driven by an arm cylinder 7, and a bucket 10 driven by a bucket cylinder 9; and a counter weight 12 mounted on the upper swing structure 1, and provided with a built-in weight body to maintain a balance of the equipment during the operation of the equipment.
As illustrated in FIG. 2, a power generator for driving a drive part of the excavator includes an engine 13, a main hydraulic pump 15 driven by the engine 13 to supply hydraulic fluid to an actuator (e.g. a hydraulic cylinder and so on) 14 of the working device; a control valve (MCV) 16 installed in a flow path between the hydraulic pump 15 and the actuator 14 to control the flow direction of the hydraulic fluid being supplied to the actuator 14; a radiator 23 cooling an engine cooling water; an oil cooler 24 cooling the high-temperature hydraulic fluid returning from the control valve 16 to a hydraulic tank T; an auxiliary hydraulic pump 19 supplying the hydraulic fluid to a hydraulic motor 18 driving a radiator fan 17; and an auxiliary hydraulic pump 22 supplying the hydraulic fluid to a hydraulic motor 21 driving the oil cooler fan 20.
As illustrated in FIG. 3, according to a conventional engine room for construction equipment, the external air (the moving directions of which are indicated as arrows in the drawing) inhaled into the engine room through an inlet port A formed on an outer wall 27 during rotation of a radiator fan 17 is discharged to an outside through outlet ports B and C. The external air inhaled into the engine room passes through the radiator 23, and cools the engine cooling water in a tube through mutual heat exchange. The external air, having passed through the radiator 23 cools the engine body, passes through the circumference of the engine 13 to cool the engine body.
The exhaust gas discharged from the engine 13 is discharged to the atmosphere through a muffler 25. Dust and so on included in the external air inhaled into an inhalation system of the engine 13 can be filtered by an air cleaner 26.
As illustrated in FIG. 4, according to another conventional engine room for construction equipment, the engine 13 is arranged in an airtight space to prevent the noise generated in the engine room 13 from emitting out of the engine room 13. In this case, it is required to cool heat-generating components such as the radiator 23 and so on, and thus openings for circulating the external air are formed on the outer wall 27.
If the diameters of an inlet port E formed on the outer wall 27 of the engine room to inhale the external air and an outlet port D to discharge the internal air to an outside are reduced, it becomes difficult to smoothly discharge the air in the engine room to the outside. Accordingly, due to high heat generated in the engine room, a sound-absorbing material and so on installed in the engine room may catch fire.
In addition, even in the case of making the engine room airtight due to the noise generated during operation of the radiator fan 17, the noise problem cannot be basically solved. Accordingly, schemes for lowering the rotating speed of the radiator fan 17 to reduce the noise of the radiator fan 17 and to enlarge the size of the radiator fan 17 have been proposed.
The enlarged radiator fan 17 occupies much space in the engine room, and causes the manufacturing cost to be increased.