JPH11193719A - Engine cooling device of working equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability of a driving means by making an interval longer between dust removals by reversely driving a fan, while ensuring engine cooling with good operability. SOLUTION: This engine cooling device is provided with a fan 9 for engine cooling, a dustproof net 11, a driving means 12 that can be switched between a first driving state for cooling that positively drives the fan 9 and a second driving state for dust removal that reversely drives the fan 9, and a control means 35 that controls the driving means 12 so that it repeats switching to the first driving state for a first set period and to the second driving state for a second set period. This device is also provided with a sensor 60 that detects a temperature of cooling water, and a control means 36 that switches the control means 35 to a control mode for controlling the driving means 12 when the result detected by the sensor 60 is at or under the set temperature and switches the driving means 12 to the second driving state for a third set period when the result detected by the sensor 60 is higher than the set temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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, a dust net for removing dust from cooling air in a cooling air path, and a dust net through the dust net. A drive means is provided which can be switched between a first driving state for cooling, in which the fan is driven to rotate in a normal direction so as to take in air, and a second driving state for dust removal, in which the fan is driven in a reverse direction so as to exhaust air through a dustproof net. The driving means is switched to the first driving state over time and
The present invention relates to a device provided with a control device for controlling the driving means so that switching of the driving means to the second driving state over a set time is repeated as one interval.

[0002]

2. Description of the Related Art When an engine cooling device for a work machine of this type is used, the driving means switches to a second driving state for a second set time at each interval, and the fan is driven in reverse, so that dust in the dustproof net is reduced. Clogging due to backwashing is eliminated by backwashing and the expected cooling performance is maintained, so the operator does not need to consider the deterioration of cooling performance due to dust clogging and operates the expected cooling performance Remember that you can do it with good operability.

[0003] Conventionally, as an engine cooling device of a combine as an example of an engine cooling device of a work machine, a control device is started by a start signal accompanying the engagement of a threshing clutch to control a driving means, that is, a fan. It is known that control is performed. Conventionally, the driving means is switched to the second state at a relatively short interval of about three minutes to ensure that dust is removed and that the engine cooling performance is reduced due to dust adhesion. The prevention was ensured.

[0004]

However, considering the durability of the driving means, it is desirable to reduce the number of times the driving means is switched between the first driving state and the second driving state as much as possible. Especially,
As shown in an embodiment described later, when mechanical switching between forward rotation and reverse rotation is performed, mechanical elements such as belts and bearings are significantly worn compared to the case where switching is not performed,
The degree of decrease in durability is large.

SUMMARY OF THE INVENTION An object of the present invention is to improve the durability of the driving means by extending the interval of dust removal by driving the fan in the reverse direction, while reliably cooling the engine with good operability.

[0006]

The features, functions and effects of the first aspect of the present invention are as follows.

[Features] An engine cooling fan is provided,
A cooling dust path is provided in the cooling air path, and a first driving state for cooling the fan to rotate in a normal direction so as to draw air through the dust preventing screen and a dust driving apparatus for driving the fan in a reverse direction so as to exhaust air through the dustproof mesh. A drive means that can be switched between the second drive state and the second drive state, and switching the drive means to the first drive state for a first set time and switching the drive means to the second drive state for a second set time are repeated as one interval. Control device for controlling the driving means, the engine cooling device of the working machine provided with a sensor for detecting the temperature of the cooling water, the control for performing the above control when the detection result of this sensor is below the set temperature The control unit is switched to a mode, and when the detection result of the sensor is higher than the set temperature, the drive unit is turned over for a third set time. The second lies in is provided with control means for switching the drive state Te.

[Operation] If the first set time is lengthened and the dust removal interval is increased by driving the fan in the reverse direction, the amount of dust adhering to the dust net increases. On the other hand, when the amount of dust adhering to the dustproof net increases, the amount of intake air by the fan decreases, and the engine cooling performance decreases. Focusing on the above points,
According to the first aspect of the present invention, the sensor and the control unit are provided, and when the cooling water temperature is equal to or lower than the set temperature, the dustproof net can be properly ventilated by removing dust at set intervals defined by the first set time. It is determined that the engine cooling performance can be maintained satisfactorily while maintaining the state, and control in the control mode is performed by the control device.On the other hand, when the cooling water temperature exceeds the set temperature, dust is removed at set intervals. The engine cooling performance is determined to deteriorate if left unattended without being able to eliminate the clogging of the dust-proof net, and the driving means is immediately switched to the second
Since dust is removed by driving the fan in the reverse direction by switching to the driving state, it is possible to maintain the engine cooling performance satisfactorily while extending the first set time and extending the dust removal interval. In other words, if the dust removal interval is lengthened, clogging of the dust-proof net, which lowers the engine cooling performance, is likely to occur.However, as the clogging progresses, the cooling water temperature rises and when the temperature exceeds the set temperature, the fan reverses. Since the dust is removed by driving, the clogging of the dust-proof net can be eliminated before the engine cooling performance is reduced, and the engine cooling performance can be maintained satisfactorily.

[Effects] Therefore, according to the first aspect of the present invention, by automatically driving the fan in the reverse direction to remove dust at set intervals, the fan can be reliably cooled with good operability. The durability of the driving means can be improved by increasing the interval of dust removal by reverse rotation driving.

According to the second aspect of the present invention, the features, actions,
The effects are as follows.

[Features] In the features of the first invention,
As the control means, after the third set time has elapsed, the fourth
The point is that means for switching the driving means to the first driving state over the set time is provided.

According to the second aspect of the present invention, the engine is cooled by switching the driving means to the first driving state for the fourth set time after the dust is removed by reversely driving the fan for the third set time. As a result, the temperature of the cooling water that has risen during dust removal can be reduced.

[Effects] Therefore, according to the second aspect of the present invention, engine cooling can be performed more reliably and stably.

[0014]

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-type traveling device 1 and rearwards. And a threshing device 4 for threshing the culm from the reaping unit 3, a boarding operation unit 5, and a tank 6 for storing threshing grains. It is configured with.

A water-cooled engine 7 is arranged below the driver's seat 5A of the boarding driver 5, as shown in FIG.

As shown in FIG. 2, in the engine cooling device, a radiator 8 for cooling the engine and a fan 9 for cooling the engine are arranged below the driver's seat 5A, and a cooling air passage to the radiator 8 is provided. 10, more specifically, a dustproof net 11 for removing dust from cooling air is provided at an intake port 8A of the radiator 8, and a driving means 12 for driving the fan 9 and a fan control means 13 are provided.

The fan 9 is rotatably mounted on a support shaft 14 attached to the engine 7 while being located between the engine 7 and the radiator 8.

The driving means 12 includes a first driving state for cooling in which the fan 9 is driven to rotate in a normal direction so as to draw air through the dustproof net 11 and the radiator 8 in the order described, and the radiator 8 and the dustproof net 11 This is a means that can be switched to the second driving state for dust removal in which the fan 9 is driven in the reverse direction so as to exhaust air in the order described. Specifically, as shown in FIGS. 3 to 6, an output pulley 15 mounted on an output shaft 7 a of the engine 7, an input pulley 17 of an alternator 16 mounted on the engine 7, and rotatably mounted on the support shaft 14. A first transmission belt 19 is wound around the idler pulley 18, and the rotation of the first transmission belt 19 can be switched between a forward transmission state in which the fan 9 is forwardly transmitted and a reverse rotation state in which the first transmission belt 19 is reversely transmitted. A switching mechanism is provided. As shown in FIGS. 3 to 6, the transmission switching mechanism rotatably mounts a switching frame 20 on the support shaft 14, and attaches the switching frame 20 to the switching frame 20.
Is in the forward rotation swing posture, the forward rotation passive pulley 21 that contacts the inner peripheral surface of the first transmission belt 19 at the large diameter portion 21a and is driven to rotate forward, and the switching frame 20 is in the reverse rotation swing posture. At this time, a reverse passive pulley 22 that is driven in reverse rotation while being in contact with the outer peripheral surface of the first transmission belt 19 at the large diameter portion 22a is rotatably attached, and the fan pulley 9a that rotates integrally with the fan 9 and the forward passive pulley 21 are rotated. The second transmission belt 23 is wound around the small diameter portion 21b of the reverse rotation pulley 22 and the small diameter portion 22b of the reverse rotation pulley 22, and operating means is provided for switching the switching frame 20 between a forward rotation posture and a reverse rotation posture. I have. In other words, by swinging the switching frame 20 to the forward swinging posture, the rotating power of the first transmission belt 19 is passively transmitted by the forward passive pulley 21 and transmitted to the fan pulley 9 a via the second transmission belt 23. The fan 9 is driven to rotate forward, the switching frame 20 is swung to the reverse swinging posture, and the rotating power of the first transmission belt 19 is passively driven by the reverse passive pulley 22 to the fan pulley 9 a via the second transmission belt 23. The transmission drives the fan 9 in the reverse direction. As shown in FIGS. 5 and 6, the operating means includes a spring 2 for urging the switching frame 20 to the forward swinging posture.
4 and a cable 25 for pulling and swinging the switching frame 20 to the reverse swinging posture against the urging force of the spring 24.
By rotating in one direction, the cable 24 is pulled to actuate the spring 24 while loosening the cable 25, while rotating in the opposite direction causes the spring 2 to rotate.
An operation frame 27 that pulls the cable 25 while loosening the operation frame 4 is provided, and the drive gear 29 that meshes with a passive gear 28 that rotates integrally with the operation frame 27 is rotated forward and reverse to rotate the operation frame 27 forward and backward. The motor 30 is provided. Reference numeral 31 denotes a tension pulley that constantly applies tension for transmission to the first transmission belt 19.

As shown in FIG. 7, the fan control means 13 is a sensor for detecting the on / off state of the key switch 32 for the engine 7 and the temperature of the cooling water of the upper hose of the radiator 8 as the cooling water temperature. A means for controlling the driving means 12 based on the detected temperature t at 60, and includes a control device 35 and a control means 36.

The control device 35, as shown in FIG.
When the key switch 32 is turned on in step # 1 and the detected temperature t of the sensor 60 is equal to or lower than the set temperature t0 in step # 2, as shown in FIG. 8A, the drive unit 12 is turned on for the first set time T1. The driving unit 12 is controlled so that switching to the first driving state and switching of the driving unit 12 to the second driving state for a second set time T2 shorter than the first set time T1 are repeated as one interval (# 3 to # 6). Step).

The set temperature t0 is preferably a temperature higher than the proper cooling water temperature and lower than the dangerous temperature that may cause overheating and the like, and is preferably as close as possible to the proper cooling water temperature.

The control means 36, as shown in FIG.
When the key switch 32 is turned on in step # 1 and the detected temperature t of the sensor 60 exceeds the set temperature t0 in step # 2, as shown in FIG.
After switching to the second drive state for the set time T3, the drive means 12 is switched to the first drive state for the fourth set time T4 longer than the third set time T3 (# 7 to # 10 steps). In addition, as an example of real numerical values, the first
The set time T1 is 8 minutes and 50 seconds, and the second set time T2 is 10
Second, the third set time T3 is 10 seconds, that is, the same as the second set time T2, the fourth set time T4 is 30 seconds, and the set temperature t0 is 103 ° C.

Therefore, when the key switch 32 is turned on and the engine 7 is started, if the temperature t detected by the sensor 60 is equal to or lower than the set temperature t0, the control unit 35 causes the driving unit 1 to operate.
2 is controlled, the engine cooling by the forward rotation of the fan 9 over the first set time T1 and the second set time T2
The dust removal by the reverse rotation of the fan 9 is alternately performed. On the other hand, if the detected temperature t exceeds the set temperature t0, the driving device 12 is controlled by the control means 36, and after the dust is removed by the reverse rotation driving of the fan 9 for the third set time T3, the fourth The fact that the engine is cooled by the forward drive of the fan 9 over the set time T4
The control is repeated until the detected temperature t becomes equal to or lower than the set temperature t0. When the detected temperature t becomes equal to or lower than the set temperature t0, the control is switched to the control by the control device 35. Of course, if the detected temperature t falls below the set temperature t0 in one control,
Immediately, the control is switched to the control by the control device 35. .

[Alternative Embodiment] In the above-described embodiment, the means for mechanically switching the driving direction is shown as the driving means 12, but the driving means 12 is constituted by an electric motor capable of switching between forward and reverse directions. Is also good.

In the above embodiment, an example in which the combine is applied to an engine cooling device is described. However, the present invention can be applied to an engine cooling device for various working machines such as a tractor.

In the above embodiment, the third set time T3 is set to be equal to the second set time T2, but these may be different.

In the above embodiment and other embodiments,
First set time T1, second set time T2, third set time T
3. The fourth set time T4 is configured to be adjustable.

[Brief description of the drawings]

FIG. 1 is a side view of a combine.

FIG. 2 is a longitudinal sectional front view of a main part.

FIG. 3 is a side view of a transmission switching mechanism in a forward drive state.

FIG. 4 is a side view of the transmission switching mechanism in a reverse rotation driving state.

FIG. 5 is a side view of the operating unit in a forward rotation driving state.

FIG. 6 is a side view of the operation unit in a reverse rotation driving state.

FIG. 7 is a control block diagram.

FIG. 8 is a time chart of forward rotation and reverse rotation.

FIG. 9 is a control flowchart of a driving unit.

[Explanation of symbols]

 9 Fan 10 Cooling air path 11 Dustproof net 12 Driving means 35 Control device 36 Control means 60 Sensor T1 First setting time T2 Second setting time T3 Third setting time T4 Fourth setting time

Claims (2)

[Claims] A first cooling fan that is provided with a fan for cooling the engine, a dust screen for removing dust from the cooling air in a cooling air passage, and a normal rotation of the fan so as to draw air through the dust screen;
Driving means is provided which can be switched between a driving state and a second driving state for dust removal, in which the fan is driven in reverse so as to exhaust air through the dustproof net. The driving means is switched to the first driving state for a first set time and the second setting is performed. An engine cooling device for a working machine provided with a control device for controlling the driving means so as to repeat switching the driving means to the second driving state over time as one interval, provided with a sensor for detecting a cooling water temperature, When the detection result of the sensor is equal to or lower than the set temperature, the control device is switched to a control mode for performing the control, and when the detection result of the sensor is higher than the set temperature, the driving unit is turned on for a third set time. An engine cooling device for a working machine, comprising: a control unit for switching to a second drive state over the second driving state. 2. The engine cooling device for a working machine according to claim 1, wherein said control means includes means for switching the drive means to the first drive state for a fourth set time after a third set time has elapsed.