JPH04311619A - Cooler fo engine - Google Patents

Abstract

PURPOSE:To controllably turn on and off an auxiliary motor fan properly if necessary. CONSTITUTION:In an engine cooling device provided with an auxiliary motor fan for sucking from the outside a portion of cooling air sent to an engine or radiator thereof are provided a load condition detecting means for detecting the load condition of the engine and a controlling means H to operate the auxiliary motor fan 18 on the basis of the detecting information only when the engine load exceeds a set value. The Load condition detecting means is provided with a working machine operation detecting means SW1 for detecting the operation of the working machine driven by the engine, a vehicle speed detecting means S1 for detecting vehicle speed and an engine rotational frequency detecting means S2 for detecting the rotational frequency of the engine. The controlling means H judges whether or not the engine load exceeds the set value on the basis of the detecting information from these detecting means SW1, S1, S2.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cooling system equipped with an auxiliary electric fan that draws in a portion of cooling air to an engine or its radiator from the outside.

0002

2. Description of the Related Art Conventionally, such auxiliary electric fans have been operated and stopped by an operator using an on/off switch as necessary.

0003

[Problems to be Solved by the Invention] However, in reality, appropriate on/off switching is rarely performed, and in many cases, the auxiliary electric fan is left operating at all times to prevent the engine from overheating. This is unfavorable from the standpoint of energy saving, and at the same time has the disadvantage that the dustproof screen becomes clogged quickly, which tends to lead to a decrease in cooling capacity.

The present invention has been made in view of the above circumstances, and its purpose is to appropriately control on/off of an auxiliary electric fan as required.

[0005]

[Means for Solving the Problems] The engine cooling device of the present invention is provided with an auxiliary electric fan that takes in a part of the cooling air to the engine or its radiator from the outside, and has a first characteristic configuration. is a load state detection means for detecting the load state of the engine, and based on the detected information,
The present invention is characterized in that a control means is provided for operating the auxiliary electric fan only when the load on the engine is equal to or higher than a set value.

[0006] The second characteristic configuration specifies a preferred specific configuration for implementing the first characteristic configuration, and the engine is mounted on a work vehicle to drive a traveling device and a work implement. , the load state detection means includes a work machine operation detection means for detecting the operation of the work machine, a vehicle speed detection means for detecting vehicle speed, and an engine rotation speed detection means for detecting the rotation speed of the engine, and the control The means stores an engine speed when the working machine is in operation and a vehicle speed is less than a set value as an initial engine speed, and stores the engine speed and the current engine speed as the vehicle speed becomes equal to or higher than the set value. The present invention is configured to determine that the load on the engine is greater than or equal to the set value when the difference between the number and the number is greater than or equal to the set value.

[0007]

[Operation] It is necessary to utilize the auxiliary electric fan's function of increasing cooling capacity and preventing engine overheating when the engine load is large. Therefore, the first
According to the characteristic configuration, the control means operates the auxiliary electric fan only when the engine load is equal to or higher than a set value based on the detection information of the load state detection means.

Although a torque sensor may be used as the load state detection means, according to the second characteristic configuration, it is possible to determine whether the load is equal to or higher than a set value based on the engine rotation speed or the like. can. Here, the engine speed when the work machine is in operation and the vehicle speed is less than the set value means the engine speed when the work machine is under no load. In other words, it is the engine rotation speed before work. The control means stores this as the initial rotation speed.

[0009] When the vehicle speed exceeds a set value and a load is generated on the working machine, the load on the engine increases. Since the engine speed decreases as the load increases, it is determined that the engine load is greater than the set value when the difference between the initial engine speed and the current engine speed exceeds the set value.

0010

According to the first characteristic configuration, it is now possible to perform appropriate on/off control of the auxiliary electric fan according to the needs based on the load condition of the engine. or,
According to the second characteristic configuration, the auxiliary electric fan is appropriately controlled by determining whether the engine load is equal to or higher than the set value based on the engine speed, etc., without using a torque sensor or the like that increases cost. It is now possible to perform on/off control. As a result, the hassle of manual switching is eliminated, and compared to the case where the switch is always on, it is superior in terms of energy savings and the difficulty of clogging the dustproof screen.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a full-culm input type combine harvester will be described below with reference to the drawings.

First, the overall outline of the combine harvester is as shown in a plan view and a side view in FIGS. 3 and 4. A crawler traveling device 2 is provided at the bottom of a machine body on which a threshing device 1 as a working machine is mounted, and a preprocessing device 3 is provided in front of the crawler traveling device 2. The pre-processing device 3 includes a raking device 4 and a reaping device 5 for raking and reaping the planted grain culms, an auger 6 for moving the cut grain culms to the center in the width direction of the machine body, and a gathered grain culm. A conveyor 7 is provided to convey the grains to the threshing device 1. A driving unit 8 and a grain tank 9 are provided on the right side of the threshing device 1, and a control room is provided in front of the driving unit 8.

[0013] The driving unit 8 is equipped with an engine and its auxiliary equipment. As shown in FIG. 2, an engine 12 is mounted on a body frame 10 via a vibration-proof rubber 11, and a frame 13 is provided to surround the engine 12. A radiator 14, a muffler 15, an air cleaner 16, a radiator cooling fan 17, and an auxiliary electric fan 18 are attached to the frame 13.

A chamber is formed in the upper part of the engine 12 by a frame 13. A dustproof net 19 is provided on the surface where the air cleaner 16 is attached, that is, on the outer side of the aircraft.
An exhaust cover 20 is attached to the side where the radiator 14 and the radiator cooling fan 17 are attached, that is, the surface on the side of the thresher 1. The bottom surface is separated from the engine 12 by a dustproof net 21.

The radiator 14, the radiator cooling fan 17, and the auxiliary electric fan 18 constitute an engine cooling system, which operates as follows. That is, the outside air taken in by the radiator cooling fan 17 mainly through the dustproof net 19 cools the radiator 14 as cooling air, and then is exhausted through the exhaust cover 20. The cooling water cooled by the radiator 14 is circulated through the crankcase, cylinder head, etc. in the engine 12 by a water pump (not shown) to cool them.

A part of the cooling air that cools the radiator 14 is also taken in through the dustproof net 21 and is sent to the auxiliary electric fan 18.
acts to increase this. Further, a part of the outside air taken in by the auxiliary electric fan 18 becomes cooling air that directly cools the engine 12.

The engine cooling system also includes a control means H, as shown in the block diagram of FIG. The engine load condition is detected based on the detection information, and the motor 18a of the auxiliary electric fan 18 is driven to rotate only when the engine load is equal to or higher than a set value. An explanation will be added below.

The work machine operation detection means SW1 is a switch (hereinafter referred to as a threshing switch) that is turned on when the threshing device 1 as a work machine is in operation. In reality, the threshing switch SW1 transfers the power of the engine 12 to the threshing device 1.
The threshing clutch is installed so that the contact closes when the threshing clutch is connected.

The vehicle speed detection means S1 is a crawler traveling device 2.
The rotary encoder generates a pulse signal in accordance with the rotation of the drive wheels of the vehicle, and generates a pulse signal with a frequency proportional to the vehicle speed and supplies it to the control means H. The engine rotation speed detecting means S2 is an electromagnetic pickup coil provided so as to face the outer circumference of a spur gear fixed to the camshaft of the engine 12, and is a control means for generating a pulse signal with a frequency proportional to the engine rotation speed. Give to H.

Based on the detection information of the three detection means SW1, S1, and S2, the control means H performs the control shown in FIG. 2. That is, the engine rotation speed when the threshing device 1 is in operation and the vehicle speed is less than a set value (for example, 0.1 m/s) is stored as the initial rotation speed (R0), and when the vehicle speed exceeds the set value, the engine speed is stored as the initial rotation speed (R0). Accordingly, when the difference (ΔR=R0-R) between the initial rotation speed (R0) and the current engine rotation speed (R) exceeds a set value (for example, 20 rpm), the fan motor 18a
Activate.

[0021] "When the thresher 1 is in operation and the vehicle speed is less than the set value" means the state before the threshing clutch is connected and the reaping operation begins. However, it is assumed that the reaping clutch that operates the pre-processing device 3 is also connected. Therefore, the threshing device 1 and the pretreatment device 3 are operating without load. The engine speed at this time is stored as an initial speed, and this initial speed is updated every processing cycle until the vehicle speed reaches a set value or higher.

When the vehicle speed exceeds the set value, the initial rotation speed is fixed at the previous value, and the difference (Δ
R) will be calculated for each processing cycle. When the reaping work and accompanying threshing work begin, the engine speed (R) decreases as the load on the engine 12 increases, and the above-mentioned speed difference (ΔR) increases.

Therefore, the control means H controls the rotational speed difference (ΔR)
If the value exceeds the set value, it is determined that the engine load is greater than the set value, and the fan motor 18a is operated. Note that when the threshing device 1 is not in operation, when the vehicle speed is less than the set value, and when the rotation speed difference (ΔR) is less than the set value, the fan motor 18a is stopped.

Other examples will be listed below. (2) In the above embodiment, the operating state of the threshing device 1 as a working machine was checked, but the operating state of the pre-processing device 3 may be checked instead. In this case, a signal from a reaping switch whose contacts are configured to close when the reaping clutch is connected is detected. Alternatively, an OR condition or an AND condition for both may be used. ■ In order to detect the load state of the engine 12, the method of the above embodiment is not limited. A torque sensor is provided in the power transmission system from the engine 12 to the working machine (threshing device 1, etc.), and the detected information is used to detect the load state of the engine 12.
There is also a method of determining the load status of (2) The rotational speed of the fan motor 18a may be made variable, and the load condition of the engine 12 may be determined in stages based on the engine rotational speed, etc., and the control may be such that the rotational speed of the auxiliary electric fan 18 increases as the load increases. (2) The present invention is applicable not only to the full-culm input type combine harvester of the above embodiment, but also to self-removal type combine harvesters and even construction machines such as bulldozers.

[0025] Note that although reference numerals are written in the claims for convenience of comparison with the drawings, the present invention is not limited to the structure of the accompanying drawings.

[Brief explanation of drawings]

FIG. 1 is a control block diagram of an engine cooling device according to an embodiment of the present invention.

[Figure 2] Flow chart of engine cooling system control

[Figure 3
] A perspective view of the driving part of the combine harvester of this example seen from the back.

[Figure 4] Plan view of the combine harvester

[Figure 5] Side view of the combine harvester

[Explanation of symbols]

1 Work equipment 2 Traveling device 12 Engine 14 Radiator 18 Auxiliary electric fan H Control means S1 Vehicle speed detection means S2 Engine speed detection means SW1　Work machine operation detection means

Claims (2)

[Claims] 1. An engine cooling device provided with an auxiliary electric fan (18) for sucking a part of cooling air into an engine (12) or its radiator (14) from the outside, the engine cooling device comprising: A load state detection means for detecting a load state, and based on the detection information, the engine (
12) An engine cooling device provided with a control means (H) that operates the auxiliary electric fan (18) only when the load on the engine is equal to or higher than a set value. 2. The engine (12) is connected to a traveling device (
2) and is mounted on the work vehicle to drive the work implement (1), and the load state detection means includes work implement operation detection means (SW1) that detects the operation of the work implement (1), and detects the vehicle speed. a vehicle speed detection means (S1), and the engine (12).
The control means (H) detects the engine speed when the work implement (1) is in operation and the vehicle speed is less than a set value. The load on the engine (12) is stored as an initial rotation speed, and when the difference between the initial rotation speed and the current engine rotation speed becomes greater than or equal to the set value as the vehicle speed becomes greater than or equal to the set value. The engine cooling system according to claim 1, wherein the engine cooling system is configured to determine that there is a problem.