Abstract: A cooling device includes: a cooling fan; a shroud provided at an outer circumferential side of the cooling fan; an inner circumferential wall provided on the shroud and adjacent to the outer circumference of the cooling fan so as to surround the cooling fan; an outer circumferential wall provided to surround the inner circumferential wall. An air-flow-direction downstream side end of the outer circumferential wall is positioned at a further downstream position in an air flow direction than an air-flow-direction downstream side end of the inner circumferential wall. The cooling fan is rotatable within a space provided on a radially inner side of the inner circumferential wall. The air-flow-direction downstream side end of the outer circumferential wall is provided at a further upstream position in the air flow direction than an air-flow-direction downstream side end of the cooling fan.

Abstract: A cooling device includes: a cooling fan; a shroud provided at an outer circumferential side of the cooling fan; an inner circumferential wall provided on the shroud and adjacent to the outer circumference of the cooling fan; and an outer circumferential wall provided to surround the inner circumferential wall. An air-flow-direction downstream side end of an outer circumferential edge of the cooling fan is positioned at a further downstream position in an air flow direction than an air-flow-direction downstream side end of the inner circumferential wall. An angle between: an line connecting the air-flow-direction downstream side end of the inner circumferential wall to the air-flow-direction downstream side end of the outer circumferential wall in cross section along the air flow direction of the inner circumferential wall and the outer circumferential wall; and a line orthogonal to the air flow direction, is 9 degrees or more and 45 degrees or less.

Abstract: A cooling device includes: a cooling fan; a shroud provided at an outer circumferential side of the cooling fan; an inner circumferential wall provided on the shroud and adjacent to the outer circumference of the cooling fan; and an outer circumferential wall provided to surround the inner circumferential wall. An air-flow-direction downstream side end of the outer circumferential wall is positioned at a further downstream position in an air flow direction than an air-flow-direction downstream side end of the inner circumferential wall. An air-flow-direction downstream side end of the cooling fan is positioned at a further downstream position than the air-flow-direction downstream side end of the inner circumferential wall. A ratio between a length of the outer circumferential wall and a length of the inner circumferential wall in the air flow direction is 1.07 or more and 1.81 or less, and a width between the outer circumferential wall and the inner circumferential wall is 15 mm or more and 55 mm or less.

Abstract: A cooling device includes: a cooling fan; a shroud provided at an outer circumferential side of the cooling fan; and a ring having an inner circumferential wall and an outer circumferential wall. The inner circumferential wall is provided on the shroud and adjacent to an outer circumference of the cooling fan. The outer circumferential wall surrounds the inner circumferential wall, and an air-flow-direction downstream side end of the outer circumferential wall is positioned at a further downstream position in an air flow direction than an air-flow-direction downstream side end of the inner circumferential wall. An air-flow-direction downstream side end of an outer circumferential edge of the cooling fan is positioned at a further downstream position in the air flow direction than the air-flow-direction downstream side end of the inner circumferential wall.

Abstract: A cooling device includes: a cooling fan; a shroud provided at an outer circumferential side of the cooling fan; an inner circumferential wall provided on the shroud and adjacent to the outer circumference of the cooling fan; and an outer circumferential wall provided to surround the inner circumferential wall. An air-flow-direction downstream side end of an outer circumferential edge of the cooling fan is positioned at a further downstream position in an air flow direction than an air-flow-direction downstream side end of the inner circumferential wall. An angle between: an line connecting the air-flow-direction downstream side end of the inner circumferential wall to the air-flow-direction downstream side end of the outer circumferential wall in cross section along the air flow direction of the inner circumferential wall and the outer circumferential wall; and a line orthogonal to the air flow direction, is 9 degrees or more and 45 degrees or less.

Abstract: A cooling device includes: a cooling fan; a shroud provided at an outer circumferential side of the cooling fan; an inner circumferential wall provided on the shroud and adjacent to the outer circumference of the cooling fan so as to surround the cooling fan; an outer circumferential wall provided to surround the inner circumferential wall. An air-flow-direction downstream side end of the outer circumferential wall is positioned at a further downstream position in an air flow direction than an air-flow-direction downstream side end of the inner circumferential wall. The cooling fan is rotatable within a space provided on a radially inner side of the inner circumferential wall. The air-flow-direction downstream side end of the outer circumferential wall is provided at a further upstream position in the air flow direction than an air-flow-direction downstream side end of the cooling fan.

Abstract: A cooling device includes: a cooling fan; a shroud provided at an outer circumferential side of the cooling fan; and a ring having an inner circumferential wall and an outer circumferential wall. The inner circumferential wall is provided on the shroud and adjacent to an outer circumference of the cooling fan. The outer circumferential wall surrounds the inner circumferential wall, and an air-flow-direction downstream side end of the outer circumferential wall is positioned at a further downstream position in an air flow direction than an air-flow-direction downstream side end of the inner circumferential wall. An air-flow-direction downstream side end of an outer circumferential edge of the cooling fan is positioned at a further downstream position in the air flow direction than the air-flow-direction downstream side end of the inner circumferential wall.

Abstract: A cooling device includes: a cooling fan; a shroud provided at an outer circumferential side of the cooling fan; an inner circumferential wall provided on the shroud and adjacent to the outer circumference of the cooling fan; and an outer circumferential wall provided to surround the inner circumferential wall. An air-flow-direction downstream side end of the outer circumferential wall is positioned at a further downstream position in an air flow direction than an air-flow-direction downstream side end of the inner circumferential wall. An air-flow-direction downstream side end of the cooling fan is positioned at a further downstream position than the air-flow-direction downstream side end of the inner circumferential wall. A ratio between a length of the outer circumferential wall and a length of the inner circumferential wall in the air flow direction is 1.07 or more and 1.81 or less, and a width between the outer circumferential wall and the inner circumferential wall is 15 mm or more and 55 mm or less.

Abstract: A hydraulic oil flow controller for a construction machine comprises an operating valve 6 for supplying hydraulic oil discharged from hydraulic pimps 1 and 2 to an attachment, an attachment operating unit 11 for transmitting a pilot signal corresponding to the manipulated variable of the operating valve 6 and a solenoid control valve 12 for changing the flow characteristics of the pilot signal in accordance with a command from a controller 19. An increase and/or decrease signal is sent to the solenoid control valve 12 through the controller 19 from a monitor device 18 so that the flow of the hydraulic oil supplied to the actuator of the attachment is increased and/or decreased. Accordingly, a coefficient of fluctuation of the flow relative to a coefficient of fluctuation of the manipulated variable can be decreased in the work of the attachment of a hydraulic shovel and the operation efficiency upon operation of the attachment can be improved.

Abstract: A hydraulic oil flow controller for a construction machine comprises an operating valve 6 for supplying hydraulic oil discharged from hydraulic pimps 1 and 2 to an attachment, an attachment operating unit 11 for transmitting a pilot signal corresponding to the manipulated variable of the operating valve 6 and a solenoid control valve 12 for changing the flow characteristics of the pilot signal in accordance with a command from a controller 19. An increase and/or decrease signal is sent to the solenoid control valve 12 through the controller 19 from a monitor device 18 so that the flow of the hydraulic oil supplied to the actuator of the attachment is increased and/or decreased. Accordingly, a coefficient of fluctuation of the flow relative to a coefficient of fluctuation of the manipulated variable can be decreased in the work of the attachment of a hydraulic shovel and the operation efficiency upon operation of the attachment can be improved.