JP3415003B2 - Work machine engine cooling system - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cooling device for a working machine such as a combine machine, and more particularly to a fan for cooling an engine and a dust-proof net at an intake port of a radiator. Provided,
A first driving state for cooling, in which the fan is driven forward, so as to supply the air to the radiator by sucking air from the dust-proof net, and a second driving state, for dust removal, in which the fan is driven reversely so as to exhaust the air from the dust-proof net. Providing a switchable drive mechanism, switching the drive mechanism from the second drive state to the first drive state for a first set time based on a control signal input;
The present invention relates to a device provided with a control device for performing fan control that alternately repeats switching of a drive mechanism from a first drive state to a second drive state for a second set time shorter than the set time. 2. Description of the Related Art In a conventional engine cooling device for a working machine of this type, fan control performed by starting a control device based on a control signal input switches a drive mechanism to a first drive state first. Was the control to execute. [0003] However, according to the above-described conventional technique, work is interrupted or stopped during the cooling of the engine by driving the fan in the normal direction, and the control signal is not transmitted. When the control signal is input and the control device is restarted after the control device is stopped, and the control device is restarted, the dust-prevention net includes the fan in the previous fan control after the reverse drive to remove the dust. Since the amount of dust corresponding to the engine cooling time has already adhered due to the cooling of the engine by driving the fan in the forward direction, the dust-proof net when the dust is started by driving the fan in the reverse direction after restarting is started. The amount of dust adhering to the vehicle is the sum of the dust adhering to the dust net and the dust already adhering to the engine after cooling down the engine. This may lead to a situation in which dust cannot be reliably removed by the dust removal action by driving the fan in reverse for the second set time, or clogging that may hinder engine cooling before dust removal is performed. Invite. That is, even if dust is removed periodically by driving the fan in the reverse direction, the dust cannot be removed reliably, and the engine cooling performance may be reduced. An object of the present invention is to improve dust removal performance. [0005] The features, functions and effects of the first invention according to claim 1 are as follows. [Features] A fan for cooling the engine is provided,
A dust-proof net is provided at the inlet of the radiator, and the fan is driven in the normal direction to draw air from the dust-proof net and supply it to the radiator, and the fan is driven in reverse to exhaust air from the dust-proof net to the outside. A drive mechanism that is switchable between a second drive state for dust removal and a drive mechanism that switches from the second drive state to the first drive state for a first set time based on a control signal input; An engine cooling device for a working machine provided with a control device for performing a fan control that alternately repeats switching a drive mechanism from a first drive state to a second drive state over a second set time shorter than the time, A timer that starts timing from the time when the drive mechanism switches from the second drive state to the first drive state, and a control signal input is cut off before the timer measures the first set time. And a non-volatile memory for storing the time measured by the timer provided in the case, first from when the control signal is input after the measured time is stored in the memory
The point is that the drive mechanism is configured to switch to the second drive state when a time obtained by subtracting the measured time from the set time has elapsed. According to the first aspect of the present invention, when the control signal is re-input after the control signal is cut off and the control device is stopped, and the control device is restarted, the control device is restarted. After the first set time has elapsed from the first set time, the drive mechanism is not switched to the second drive state, that is, the fan is driven in the reverse direction to switch to dust removal, but the time measured in the memory is subtracted from the first set time. Is switched to dust removal after the restart, so the amount of dust attached to the dust prevention net after the restart will be reduced due to the engine cooling before the control signal input is cut off. The sum of the dust adhering to the net and the dust adhering to the dust-proof net due to the engine cooling until the time after the restart has elapsed, that is, the dust adhering to the dust net due to the engine cooling for the first set time Becomes amount, amount of dust to be removed is not increased. In addition, it is also conceivable to perform the fan control that first performs dust removal by driving the fan in the reverse direction, thereby performing dust removal after restarting the dust attached to the dust prevention net with the engine cooling before the interruption as a dust removal target. But,
In this case, the cooling of the engine by driving the fan in the forward direction is delayed. [Effect] Therefore, according to the first aspect of the present invention, dust adhering to the dustproof net can be reliably removed by driving the fan in the reverse direction after the restart, regardless of the interruption of the fan control. In addition, it is possible to prevent the engine cooling performance from being lowered due to delay of dust removal. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a combine, which is an example of a working machine, cuts planted grain culms at the front of a self-propelled body frame 2 provided with a crawler traveling device 1. A harvesting unit 3 to be conveyed backward is connected to be able to move up and down freely, and a threshing device 4 for threshing the culm from the harvesting unit 3, a boarding operation unit 5, and a tank 6 for storing threshing grain are provided on the self-propelled body frame 2. And is configured. A water-cooled engine 7, a radiator 8 for cooling the engine, and a fan 9 for cooling the engine are arranged below the driver's seat 5A of the boarding driver 5. As shown in FIG. 2, the intake port 8 of the radiator 8
A is provided with a dustproof net 10 for removing dust in the intake air to the radiator 8. As shown in FIG. 2, the drive mechanism 11 of the fan 9 is provided with a first driving state for cooling in which the fan 9 is driven to rotate in a normal direction so as to draw air from the dustproof net 10 and supply it to the radiator 8. The engine 7 and the engine can be switched to a second driving state for dust removal in which the fan 9 is reversely driven so as to exhaust the dust from the net 10 to the outside and blow off dust adhering to the dustproof net 10 to the outside. The rotation switching mechanism 12 is configured to switch between a first state in which power is transmitted to the fan 9 as forward rotation power and a second state in which power is transmitted as reverse rotation power. As shown in FIG. 2, the engine cooling device is started by turning on an engine start switch 13 to switch the drive mechanism 11 to the first drive state, that is, to set the rotation switching mechanism 12 to the first state. The first control unit 14 for switching and the threshing switch 15 that is reversibly turned on by the engagement of a threshing clutch interposed in the transmission system from the engine 7 to the threshing device 4 are turned on, and the engine speed is higher than a set value. Is activated when a control signal is input and the rotation control mechanism 12 is controlled in preference to the first control unit 14, and either the threshing switch 15 is turned off or the rotation speed less than the set value is detected. The second control unit 18 which stops operation when the operation is performed, the timer T, and the non-volatile memory M
And a control device 19 having: As shown in FIG. 3, the second control unit 18 basically changes the rotation switching mechanism 12 from the second state to the first state for the first set time T1 based on the input of the control signal. The fan control is performed so that the switching and the switching of the rotation switching mechanism 12 from the first state to the second state are alternately performed over a second set time T2 shorter than the first set time T1. The fan control is started by switching the rotation switching mechanism 12 to the first state. The timer T has a rotation switching mechanism 12
Starts timing from time t1 when the second state is switched to the first state and time ta when the control signal is input, and is reset when the rotation switching mechanism 12 switches to the second state. [0015] The memory M stores the timer T
When the input of the control signal is stopped before the set time T1 is measured, the measured time T3 of the timer T at t2 is stored. When the control signal is input after the clock time T3 is stored in the memory M, the second control unit 18 starts from the first set time T1 through the clock time T1 when the control signal is input.
The rotation switching mechanism 12 is switched to the first state until the time T4 after subtracting 3 has elapsed, and when the time has elapsed, the rotation switching mechanism 12 is switched from the first state to the second state at t3. As a specific numerical example, the set value is 500 rpm, the first set time T1 is 150 seconds, and the second set time T2 is 30 seconds. Therefore, according to the above configuration, when the engine start switch 13 is turned on, the fan 9 is rotated forward to cool the engine, the threshing switch 15 is turned on, and the engine tachometer 16 exceeds the set value. When the rotation speed is detected and a control signal is input, the engine cooling is performed by driving the fan 9 in the normal direction over the first set time T1 and the dust is removed by driving the fan 9 in the reverse direction over the second set time T2 to cool the engine. It is performed alternately in the state of being executed first. And FIG.
As shown in the figure, when the control signal is cut off during the cooling of the engine and the control device 19 stops operating, and then the control signal is input and the control device 19 is restarted, the deducted time T
4, the engine is cooled by driving the fan 9 in the normal direction, and when the subtracted time T4 elapses, dust is removed by driving the fan 9 in the reverse direction. Engine cooling by driving the fan 9 forward for one set time T1 and dust removal by reverse driving the fan 9 for the second set time T2 are alternately repeated. [Alternative Embodiment] In the above-described embodiment, the drive mechanism 11 is composed of the engine 7 and the rotation switching mechanism 12, but the drive mechanism 11 is an electric motor that can be switched between forward and reverse rotation. May be. In the above embodiment, an example in which the combine is applied to an engine cooling device is shown. However, the present invention can be applied to an engine cooling device of various working machines such as a tractor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a combine. FIG. 2 is a control block diagram. FIG. 3 is a time chart showing a drive state of a fan when an engine start switch is turned on and off. 8 Radiator 8A Intake port 10 Dustproof net 11 Drive mechanism 19 Controller T Timer M Memory T1 First set time T2 Second set time T3 Timed time T4 Time

Claims (1)

(57) [Claims] [Claim 1] A fan for cooling an engine is provided, a dust-proof net is provided at an intake port of a radiator, and the fan is driven to rotate forward so that air is taken from the dust-proof net and supplied to the radiator. A driving mechanism is provided which can be switched between a first driving state for cooling and a second driving state for dust removal in which the fan is driven in reverse so as to exhaust air from the dustproof net to the outside. Switching the drive mechanism from the second drive state to the first drive state for a set time;
An engine cooling device for a working machine provided with a control device that performs a fan control that alternately repeats switching a driving mechanism from a first driving state to a second driving state for a set time, wherein the driving mechanism is a second driving state. A timer that starts counting from the point in time when the state is switched to the first driving state, and a nonvolatile memory that stores the counting time of the timer when the input of the control signal is interrupted before the timer counts the first set time. And the drive mechanism is switched to the second drive state when a time obtained by subtracting the clock time from the first set time has elapsed since the control signal was input after the clock time was stored in the memory. The engine cooling device of the working machine configured as follows.