JP2017057809A - Engine cooling device for operation vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate a maintenance work of a rotational state switching mechanism, such as repair check work.SOLUTION: A control unit controls an actuator 40 which can switch a fan 20 for sending cooling air to a radiator between a normal rotation state of a normal rotational operation for cooling, and a reverse rotation state of a reverse rotational operation for dust removal, the control unit having a control mode switchable between a normal operation mode and a maintenance mode. In the normal operation mode, the control unit controls the operation of the actuator 40 so as to be switchable between the normal rotation state and the reverse rotation state. In the maintenance mode, the control unit controls the operation of the actuator 40 so as to be switched to a neutral state in which both inner idler wheel 24 and outer idler wheel 25 do not receive a motive power from a driving-side endless rotational body 23.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an engine cooling device for a work vehicle. More specifically, the present invention relates to a fan that is driven by engine power and passes cooling air to a radiator, and a normal rotation state in which the fan is driven to rotate in a normal rotation direction for cooling and dust removal. The present invention relates to an engine cooling device for a work vehicle provided with a rotation state switching mechanism that can be switched to a reverse rotation state that is rotationally driven in the reverse rotation direction.

  The engine cooling device for the work vehicle cools the radiator by rotating the fan in the normal rotation state, and blows away dust attached to the dust removing portion of the radiator by switching the fan to the reverse rotation state. Conventionally, the rotation state switching mechanism includes a transmission belt (endless rotating body on the driving side) rotated by the power of the engine, a forward rotation pulley (one driven wheel body) in contact with the inner peripheral surface of the transmission belt, and an outer periphery. A reversing pulley (the other driven wheel body) in contact with the surface and a driven belt (driven endless rotating body) wound around the input pulley of the fan. The pulley is configured to switch between a normal rotation state where the pulley is pressed against the transmission belt and a reverse rotation state where the reverse rotation pulley is pressed against the transmission belt (see, for example, Patent Document 1).

JP 2001-263063 A

  In the above-described conventional configuration, the rotation state switching mechanism is configured to switch between the normal rotation state and the reverse rotation state, and thus has the following disadvantages.

  When maintenance work such as repair and inspection is performed on the rotation state switching mechanism after the work is completed, after the engine is stopped, the rotation state switching mechanism is removed from the fuselage frame and repair and inspection work is performed. Need to do. That is, the rotation state switching mechanism includes a support portion that supports the driven wheel body, an electric motor that moves and operates the driven wheel body, a linkage mechanism that accompanies the motor, and the like when performing maintenance work. Must be removed from the frame member on the aircraft side.

  However, even when such maintenance work is performed, the rotation state switching mechanism maintains the state when the engine is stopped between the normal rotation state and the reverse rotation state. Is in pressure contact with the transmission belt. When the driven wheel is in pressure contact with the transmission belt, the driven wheel is subjected to a reaction force due to the tension of the transmission belt. As a result, when each member in the rotation state switching mechanism is removed from the frame member on the airframe side, it is difficult to perform the removal work due to the reaction force received by the driven wheel.

  Therefore, it has been desired to easily perform maintenance work such as repair and inspection for the rotation state switching mechanism.

The characteristic configuration of the engine cooling device for a work vehicle according to the present invention is as follows:
Switchable between a fan driven by engine power and passing cooling air through the radiator, a forward rotation state in which the fan is rotated in the forward rotation direction for cooling, and a reverse rotation state in which the fan is rotated in the reverse rotation direction for dust removal A rotation state switching mechanism,
The rotation state switching mechanism is
An endless rotating body on the driving side that is rotated by the power of the engine, an inner driven wheel body that is in contact with an inner peripheral surface of the endless rotating body on the driving side, and an outer driven wheel body that is in contact with the outer peripheral surface of the endless rotating body on the driving side The driven endless rotating body wound around each of the outer driven wheel body, the inner driven wheel body, and the fan driving wheel body, and the outer driven wheel body and the inner driven wheel body. And an actuator capable of changing the position,
A control unit for controlling the actuator is provided so that the control mode can be switched between a normal operation mode and a maintenance mode.
The controller is
In the normal operation mode, the forward driven state in which the inner driven wheel body is pressed against the driving endless rotating body and the outer driven wheel body is separated from the driving endless rotating body; and the outer driven wheel Controlling the operation of the actuator to alternately switch to the reverse state in which the body is pressed against the driving endless rotating body and the inner driven wheel body is separated from the driving endless rotating body;
In the maintenance mode, the operation of the actuator is controlled so that both the inner driven wheel body and the outer driven wheel body are switched to a neutral state in which power is not transmitted from the driving endless rotating body. It is in.

  According to the present invention, when performing work travel, the control unit is switched to the normal control mode, and the fan is rotated in the normal rotation state in which the fan is rotated in the normal rotation direction for cooling and in the reverse rotation direction for the dust removal. The operation of the actuator is controlled so as to alternately switch to the reverse rotation state. Then, the control unit is switched to the maintenance mode in the maintenance work for repair and inspection after the work is completed. In the maintenance mode, the control unit controls the actuator, so that both the inner driven wheel body and the outer driven wheel body are switched to a neutral state in which power is not transmitted from the driving endless rotating body.

  As a result, when removing each member in the rotation state switching mechanism from the frame member on the machine body for maintenance work, the removal work is not received from the endless rotating body on the driving side with respect to the driven wheel body. Is easy to do.

  Therefore, it has become possible to easily perform maintenance work such as repair and inspection for the rotation state switching mechanism.

In the present invention,
Neutral state detection means for detecting that the neutral state is provided,
The control unit is configured to control the operation of the engine, and in the maintenance mode, when the restart is instructed after the operation of the engine is stopped, the neutral state detection unit detects the neutral state. If it is not detected, it is preferable that the engine start process is prohibited.

  According to this configuration, in the maintenance mode, for example, each member in the rotation state switching mechanism is removed and maintenance work is performed with the engine stopped. After the maintenance work, each member in the rotation state switching mechanism is assembled again.

  When maintenance work is performed, both the inner driven wheel body and the outer driven wheel body are switched to a neutral state in which no power is transmitted from the endless rotating body on the driving side. And there exists a possibility that it may assemble | attach in the state which the attachment position of the outer driven wheel body shifted | deviated from the appropriate position. In such an improper assembly state, the neutral state detection means does not detect that the engine is in the neutral state, and therefore the engine start-up process is prohibited even if an engine restart command is issued.

  Therefore, it is possible to avoid operating the engine with the attachment positions of the inner driven wheel body and the outer driven wheel body shifted from the proper positions after the maintenance work is completed.

In the present invention,
If the neutral state detecting means does not detect that the engine is in the neutral state when the restart of the engine is commanded, it is preferable that an informing means for notifying that is provided.

  According to this configuration, in the maintenance mode, when the engine is not started even though the restart of the engine is instructed after the maintenance work is completed, the notification means acts when the engine does not start. It can be recognized that the mounting positions of the driven wheel body and the outer driven wheel body are deviated from the appropriate positions, and that the assembly is not performed properly.

  Therefore, the operator can correct the mounting positions of the inner driven wheel body and the outer driven wheel body to the appropriate positions by performing the assembly work again immediately after the notification means is activated. Can take a good response.

In the present invention,
The rotation state switching mechanism includes a support member that supports the inner driven wheel body and the outer driven wheel body, respectively.
The actuator is configured to change the position of the outer driven wheel body and the inner driven wheel body integrally by moving the support member.
It is preferable that the neutral state detection means is configured to detect the neutral state based on an operation position of the support member.

  According to this configuration, when the actuator moves the support member, the position of the outer driven wheel body and the inner driven wheel body can be changed at once, and the outer driven wheel body and the inner driven wheel body can be separately set. The configuration can be simplified compared to the configuration for moving operation. And the neutral state detection means should just detect the operation position of a support member, and can detect that it is a neutral state appropriately, although it is a simple structure.

In the present invention,
An engine bonnet is provided that is switchable between a closed state that covers the top of the engine and an open state that opens the top of the engine,
It is preferable that the rotation state switching mechanism is detachably attached to the engine bonnet.

  According to this configuration, when the engine is operated to perform normal work, the upper part of the engine is covered with the closed engine bonnet. On the other hand, when performing maintenance work such as engine repair and inspection, the engine bonnet is switched to the open state, and the upper part of the engine is opened.

  Since the rotation state switching mechanism is detachably attached to the engine bonnet, the rotation state switching mechanism can be removed from the engine bonnet when the engine bonnet is switched to the open state. That is, when the engine bonnet is in the closed state, the engine bonnet functions as a frame member on the airframe side and can support the rotation state switching mechanism. When carrying out maintenance work around the engine, the engine hood can be switched to the open state without removing the rotation state switching mechanism from the engine bonnet by removing the rotation state switching mechanism.

It is a whole side view of a combine. It is a whole top view of a combine. It is a front view of a prime mover. It is a vertical side view of a switching operation part. It is a front view which shows a rotation state switching mechanism. It is a side view of the rotation state switching mechanism in a normal rotation state. It is a side view of the rotation state switching mechanism in a reverse rotation state. It is a side view of the rotation state switching mechanism in a neutral state. It is a control block diagram. It is a flowchart of control operation. It is a figure which shows the display state of a liquid crystal display part. It is a figure which shows an alerting | reporting display state.

  Hereinafter, a case where an embodiment of an engine cooling device for a work vehicle according to the present invention is applied to a combine as an example of a work vehicle will be described with reference to the drawings.

  As shown in FIG.1 and FIG.2, the combine which concerns on this invention is provided with the cutting part 2 which reaps a planted grain cocoon in the front part of the traveling body which self-propels by the pair of left and right crawler traveling apparatuses 1,1. . A driving unit 4 whose periphery is covered with a cabin 3 is provided on the right side of the front part of the traveling machine body, and a threshing device 5 for threshing cereals harvested by the reaping part 2 and a threshing are provided at the rear part of the traveling machine body The grain tank 6 which stores the grain obtained by the process is provided in a state of being aligned in the horizontal direction. A driving unit 8 is provided in a state of being positioned below the driving seat 7 in the driving unit 4 of the traveling machine body, and an unloader 9 for discharging the grains stored in the grain tank 6 to the outside of the machine is provided.

  In this embodiment, when defining the front-rear direction of the aircraft, it is defined along the aircraft advancing direction in the working state, and when defining the left-right direction of the aircraft, the left-right direction is defined as viewed in the aircraft advancing direction. . That is, the direction indicated by reference numeral (F) in FIGS. 1 and 2 is the front side of the body, and the direction indicated by reference numeral (B) in FIGS. 1 and 2 is the rear side of the body. The direction indicated by reference sign (L) in FIG. 2 is the left side of the aircraft, and the direction indicated by reference sign (R) in FIG.

  As shown in FIG. 2, the driving unit 4 includes a driving seat 7, a front panel 10 positioned in front of the driving seat 7, a floor 11 positioned between the front panel 10 and the driving seat 7, and the driving seat 7. The side panel 12 etc. which are located in the side of the cutting part 2 side are provided.

  As shown in FIG. 1, the engine bonnet 14 has a front seat portion 14 a located on the front side of the fuselage of the engine 13, an upper surface portion 14 b located on the upper side of the fuselage of the engine 13, and a rear seat of the upper face portion 14 b 7 is provided, and an engine room is formed that is open inward in the lateral direction of the airframe and downward in the airframe. The driver seat 7 is supported on the upper part of the upper surface part 14b. An air cleaner 15 for purifying outside air and supplying combustion air to the engine 13 is provided inside the air supply chamber constituting portion 14c, and the outside air is preliminarily purified at the upper portion of the right rear portion of the cabin 3. A pre-cleaner 16 for supplying the air cleaner 15 is provided.

  As shown in FIG. 2, the engine bonnet 14, the front panel 10, the side panel 12, the floor 11, the driver's seat 7, the cabin 3, and the like are integrally connected to form a driver part structure 17. The driving unit structure 17 is supported by the body frame 18 so as to be rotatable around the vertical axis Y1 on the left rear side of the driving seat 7. The driving unit structure 17 is in a normal use posture (state shown by a solid line in FIG. 2) retreating toward the inward side of the aircraft and a maintenance posture (state shown by a phantom line in FIG. 2) protruding outward. It is configured to be switchable.

  Although the detailed configuration is not shown, the grain tank 6 is also supported by the body frame 18 so as to be rotatable around the rear longitudinal axis Y2 similarly to the operation unit structure 17, and is retracted toward the body side. The normal use posture (state indicated by a solid line in FIG. 2) and the maintenance posture protruding outward (state indicated by a virtual line in FIG. 2) can be switched. And in the state which switched the grain tank 6 to the maintenance attitude | position, it is comprised so that it can switch to the maintenance attitude | position which protruded the operation part structure 17 outward.

  As shown in FIG. 3, the engine 8, the cooling radiator 19 for cooling the engine 13, and the engine 13 are driven by the power of the engine 13 and the cooling air is passed to the driving portion 8 in the engine bonnet 14. A fan 20 is provided, and a dustproof net 21 is provided at a communication port with outside air provided on a lateral side surface of the engine bonnet 14 so as to cover the entire surface.

  A rotation state switching mechanism 22 capable of switching between a normal rotation state in which the fan 20 is rotationally driven in the forward rotation direction for cooling and a reverse rotation state in which the fan 20 is rotationally driven in the reverse rotation direction for dust removal is provided in the driving unit 8. ing. Next, the rotation state switching mechanism 22 will be described.

  As shown in FIGS. 4 and 5, the rotation state switching mechanism 22 is in contact with a first transmission belt 23 as an endless rotating body on the driving side that is rotated by the power of the engine 13 and an inner peripheral surface of the first transmission belt 23. As a forward pulley 24 as an inner driven wheel body, a reverse pulley 25 as an outer driven wheel body in contact with the outer peripheral surface of the first transmission belt 23, a forward pulley 24, a reverse pulley 25, and a fan drive wheel body A second transmission belt 27 as a driven endless rotating body wound around each of the fan drive pulleys 26, and a switching member 28 as a support member for supporting the forward rotation pulley 24 and the reverse rotation pulley 25, respectively. The switching member 28 is provided with a switching operation portion 29 that can move the switching member 28 and change the position of the forward rotation pulley 24 and the reverse rotation pulley 25 integrally.

  As shown in FIG. 8, the switching operation unit 29 is provided at a position spaced above the switching member 28, and includes an electric motor 40 as an actuator and a small-diameter output gear 41 driven by the electric motor 40. A large-diameter driven gear 42 that is engaged and driven, and a rotation operation member 43 that rotates integrally with the driven gear 42 are provided. The switching operation unit 29 is detachably attached to the engine bonnet 14.

  The first transmission belt 23 is wound around an idler pulley 31 that is rotatably supported by a rotating shaft 30 that is supported on a side surface of the engine 13, an output pulley 32 of the engine 13, and an input pulley 34 of an alternator 33. It has been turned. A tension pulley 36 is supported at the tip of a tension arm 35 that is swingably supported around the horizontal axis P1 at the top of the alternator 33. Further, a spring 37 that urges the tension arm 35 toward the first transmission belt 23 is provided. The tension pulley 36 is always pressed against the outer surface of the first transmission belt 23 by the urging force of the spring 37, and tension is applied to the first transmission belt 23.

  The fan driving pulley 26 around which the second transmission belt 27 is wound is supported on the rotary shaft 30 so as to be relatively rotatable. A base portion of the fan 20 is attached to a boss portion of the fan driving pulley 26. Therefore, the fan 20 rotates integrally with the fan driving pulley 26.

  The switching member 28 is formed in a substantially triangular flat plate shape in a side view, and one corner portion of the switching member 28 is rotatably supported on the rotary shaft 30 via a boss portion. The forward rotation pulley 24 and the reverse rotation pulley 25 are rotatably supported by the support shafts 38 and 39 positioned at the other two corner portions of the switching member 28, respectively. As shown in FIG. 5, the forward rotation pulley 24 and the reverse rotation pulley 25 include first contact portions 24 a and 25 a that contact the first transmission belt 23 and a second contact portion 24 b that contacts the second transmission belt 27, respectively. 25b are integrally formed.

  As shown in FIGS. 6 to 8, the output pulley 32 of the engine 13 rotates with the operation of the engine 13, and the first transmission belt 23 is driven in a state of constantly rotating in the direction of the arrow in the figure. . When the switching member 28 is swung to the normal rotation position A1 shown in FIG. 6, the fan 20 is rotated forward in the normal rotation direction for cooling. That is, the first contact portion 24 a of the forward rotation pulley 24 is pressed against the inner peripheral surface of the first transmission belt 23, and the power of the first transmission belt 23 is applied to the second contact portion 24 b and the second transmission belt 27 of the forward rotation pulley 24. Is transmitted to the input pulley 34 as power for normal rotation, and the fan 20 is driven to rotate forward in the clockwise direction shown in FIG.

  When the fan 20 is driven to rotate in the forward direction in this way, a normal ventilation state in which the outside air flows as cooling air from the dust screen 21 through the radiator 19 to the engine 13 side by the suction action of the fan 20.

  When the switching member 28 is swung to the reverse rotation position A2 shown in FIG. 7, the fan 20 is rotated in the reverse rotation direction for dust removal. That is, the first contact portion 25 a of the reverse rotation pulley 25 is pressed against the outer peripheral surface of the first transmission belt 23, and the power of the first transmission belt 23 is applied to the second contact portion 25 b and the second transmission belt 27 of the reverse rotation pulley 25. Is transmitted to the input pulley 34 as power for reverse rotation, and the fan 20 is reversely driven in the counterclockwise direction shown in FIG.

  Thus, when the fan 20 is driven in reverse, air flows in the direction opposite to the normal ventilation state due to the blowing action of the fan 20, and dust and the like adhering to the surface of the radiator 19 and the dust-proof net 21 are blown off.

  When the switching member 28 is swung to the neutral position A3 shown in FIG. 8, both the forward rotation pulley 24 and the reverse rotation pulley 25 are brought into a neutral state in which no power is transmitted without being pressed against the first transmission belt 23. This neutral state is a transmission state used when performing maintenance work such as inspection and repair in the rotation state switching mechanism 22.

Next, the mounting structure of the switching operation unit 29 will be described.
The electric motor 40, the driven gear 42, and the rotation operation member 43 that rotates integrally with the switching operation unit 29 are supported by the support member 44, respectively. As shown in FIGS. 4 and 5, the support member 44 is fixed to the lower side of the upper mounting plate 44 </ b> A in the horizontal posture located on the upper side and the upper mounting plate 44 </ b> A and extended downward. A vertical plate portion 44B and a diagonal reinforcing plate 44C provided over the vertical plate portion 44B are provided.

  The case portion 40a of the electric motor 40 is connected to the vertical plate portion 44B with a bolt and fixed, and the rotary shaft 40b of the electric motor 40 is inserted through the vertical plate portion 44B and protrudes to the opposite side, and the rotary shaft 40b. An output gear 41 is provided at the protruding portion. A large-diameter driven gear 42 with which the output gear 41 is engaged is fixed to a left and right fixed shaft 45 fixed on the opposite side of the vertical plate portion 44B of the support member 44 from the side where the electric motor 40 is disposed around its axis P2. It is provided in a state where it is supported rotatably. A rotating operation member 43 that rotates integrally with the driven gear 42 is attached to a horizontal surface of the driven gear 42.

  A support member 44 is detachably attached to the engine bonnet 14. A pair of left and right mounting brackets 46 having a substantially L-shaped cross section with a space in the left-right direction are fixed to the lower surface side of the bottom of the air supply chamber constituting portion 35 c in the engine bonnet 14, and are integrally fixed over the left and right mounting brackets 46. In this state, a bonnet side mounting plate 47 is provided. Four bolts 48 are fixed to the bonnet side mounting plate 47 so as to protrude downward.

  A bolt insertion hole 49 through which the four bolts 48 are inserted is formed in the upper mounting plate 44 </ b> A of the support member 44. With the four bolts 48 inserted into the bolt insertion holes 49, the upper mounting plate 44A is applied to the lower surface side of the bonnet side mounting plate 47, and the bolt 48 and the nut 50 are tightened, thereby supporting members. 44 is attached to the engine bonnet 14. The support member 44 can be removed from the engine bonnet 14 by removing the four nuts 50.

  Of the four bolts 48 that connect the upper mounting plate 44 </ b> A of the support member 44 to the bonnet side mounting plate 47, the three bolts 48 other than the bolt 48 a positioned on the right side of the front part face the bonnet side mounting plate 47 downward. It is fixed by welding in a protruding state. The bolt 48a located on the right side of the front part is configured to be able to fasten and fix the upper mounting plate 44A of the support member 44 with a nut 50 and to be detachably screw-connected to the bonnet side mounting plate 47. . For example, as shown in FIG. 2, when the operation unit structure 17 is switched to the maintenance posture, the bolt 48a located on the right side of the front portion of the bolt 48 protruding downward from the bonnet side mounting plate 47 is This is for avoiding contact with the pipe h of the intercooler 62 arranged outside the circuit 19.

  As shown in FIGS. 4, 6, and 7, a substantially fan-shaped winding member 51 that rotates integrally with the switching member 28 is provided, and one end side is provided on a pin 43 a provided on the rotation operation member 43. The other end of the connected wire 52 is connected to a pin 51 a provided on the winding member 51. In the winding member 51, a wire guide portion 51 b is formed in which the wire 52 guides in a winding state so as to bypass the outer peripheral portion of the rotating shaft 30 in an arc shape in accordance with the swinging operation of the switching member 28. A pin 43b is provided at a position spaced apart from the wire connecting pin 43a of the rotation operation member 43 in the circumferential direction. A coil spring 53, which is an operation member having a stroke absorbing function, is stretched over the pin 43b and the pin 28a provided on the swing end side of the switching member 28.

  When the electric motor 40 is driven and the rotation operation member 43 is rotated in the forward rotation position side, that is, in the clockwise direction in FIG. 4, the switching member 28 is interlocked with the coil spring 53 to rotate in the clockwise direction. Is operated. As shown in FIG. 6, when the switching member 28 is positioned at an angle corresponding to the forward rotation position A1 and the tension with respect to the first transmission belt 23 is in the proper forward rotation state, the pin 43b overcomes the dead point and 1 The tensile force applied via the coil spring 53 due to the tension of the transmission belt 23 is switched to the opposite direction, that is, the state in which the electric motor 40 rotates, and the electric motor 40 is deactivated. That state is maintained.

  The electric motor 40 has a built-in worm gear speed reduction mechanism, and even after the rotational operation of the electric motor 40 is stopped, a rotational force is applied from the driven gear 42 side by the tension of the first transmission belt 23. The rotation is blocked.

  Next, when the rotation operation member 43 is rotated about 180 ° in the counterclockwise direction by the electric motor 40, the wire 52 is pulled and the switching member 28 is also swung in the counterclockwise direction. The swinging operation is performed to the reverse rotation position A2. Then, as shown in FIG. 7, when the switching member 28 is positioned at an angle corresponding to the reverse rotation position and the tension on the first transmission belt 23 is in the proper reverse rotation state, the pin 43a gets over the dead point, and 1 The tensile force applied via the wire 52 due to the tension of the transmission belt 23 is switched to a state acting in the opposite direction, that is, in the direction of the rotation operation by the electric motor 40, and the electric motor 40 stops operating. The state will be maintained.

  In this case, when the switching member 28 is swung from the forward rotation position A1 to the reverse rotation position A2, the coil spring 53 is pulled toward the switching member 28 as the switching member 28 swings. At the same time, the pin 43a of the rotating operation member 43 to which the coil spring 53 is connected also moves to the switching member 28 side, so that the coil spring 53 has a large resistance to the swinging operation of the switching member 28 from the normal rotation position A1 to the reverse rotation position A2. Never become. In this manner, the forward rotation state and the reverse rotation state can be alternately switched by rotating the electric motor 40 in the forward and reverse directions.

  A potentiometer type operation position sensor 54 is provided as an example of a neutral position detection means that is positioned below the alternator 33 and detects the swing operation position of the switching member 28. The operation position sensor 54 is connected by a link 55 between a swing end side of an operation arm 54b provided on the sensor body 54a so as to be swingable around a horizontal axis P3 and a position on the swing end side of the switching member 28. The detection value corresponding to the swing operation position of the switching member 28 is output in conjunction with the interlocking operation.

  As shown in FIG. 9, a microcomputer-based control unit 56 that controls the operation of the electric motor 40 is provided, and detection information of the operation position sensor 54 is input to the control unit 56. A main switch 57 for turning on and off the power supply to each electric device, and a touch panel type liquid crystal display unit 58 provided on the front panel 10 of the operation unit 4 and capable of displaying various information and capable of commanding operation. Such information is also input to the control unit 56. The control unit 56 controls the operation of the electric motor 40 based on the detection information of the operation position sensor 54, and controls the operation of the engine 13 by controlling the operation of the cell motor 59 and the fuel cutoff valve 60. The operation of the display unit 58 is controlled.

  The main switch 57 is provided so as to be able to be switched to an off position where power supply to each electric device is stopped, an on position where power supply is supplied to each electric device, and a start position where the start of the engine 13 is commanded. When the main switch 57 is operated to the start position while the engine 13 is stopped, the control unit 56 operates the cell motor 59 to start the engine 13. When the main switch 57 is operated to the off position while the engine 13 is operating, the power supply to each electrical device is stopped and the control unit 56 operates the fuel cutoff valve 60 to stop the operation of the engine 13. To do.

  In the normal operation mode, the control unit 56 positions the switching member 28 at the normal rotation position A1, presses the first contact portion 24a of the forward rotation pulley 24 against the first transmission belt 23, and sets the reverse rotation pulley 25 to the first rotation mode. The forward rotation state in which the belt is separated from the transmission belt 23, the switching member 28 is positioned at the reverse rotation position A2, the first contact portion 25a of the reverse rotation pulley 25 is pressed against the first transmission belt 23, and the forward rotation pulley 24 is first transmitted. The operation of the electric motor 40 is controlled so as to be switched alternately to the reverse rotation state separated from the belt 23.

  In the maintenance mode, the control unit 56 controls the operation of the electric motor 40 so that both the forward rotation pulley 24 and the reverse rotation pulley 25 are switched to a neutral state in which power transmission from the first transmission belt 23 is not received. .

  In the maintenance mode, when the restart is instructed after the operation of the engine 13 is stopped, the control unit 56 prohibits the starting process of the engine 13 if the operation position sensor 54 does not detect the neutral state. This is displayed on the liquid crystal display unit 58 as a notification means for notification.

Hereinafter, the control operation of the electric motor 40 by the control unit 56 will be described.
When the main switch 57 is operated to the on position and the power is turned on, the control unit 56 starts the control process. As shown in FIG. 10, when the control is started, the operation is performed in the normal operation mode (step 1). That is, the normal operation mode is initially set as the control mode.

  In the normal operation mode, the switching member 28 is operated to the normal rotation position A1 to switch to the normal rotation state in which the fan 20 is driven to rotate forward, and when the set time for forward rotation (for example, about several minutes) elapses thereafter, the switching member 28 is operated to the reverse rotation position A2 to switch to the reverse rotation state in which the fan 20 is driven in reverse rotation. Then, when a reverse setting time (for example, about several seconds) elapses after switching to the reverse rotation state, the normal rotation state is again switched. The operation of switching between the forward rotation state and the reverse rotation state is repeated, and the fan 20 is driven to rotate reversely at set time intervals to blow off the dust adhering to the dust net 21. When the main switch 57 is operated to the off position and the engine stop is instructed, the fuel cutoff valve 60 is operated to stop the operation of the engine 13 (step 3).

  In order to perform maintenance work on the rotation state switching mechanism 22, when an operator operates the liquid crystal display unit 58 to command the maintenance mode, a flag is set (steps 2 and 4), and the switching member 28 is in the neutral position. The operation of the electric motor 40 is controlled so as to be operated (step 5). Thereafter, when the engine stop is instructed, the operation of the engine 13 is stopped (steps 6 and 7). In this state, the worker performs maintenance work.

  The control unit 56 determines that the switching member 28 has moved to the neutral position based on the detection information of the operation position sensor 54. In the neutral state in which the switching member 28 is in the neutral position A3, as shown in FIG. 8, neither the forward rotation pulley 24 nor the reverse rotation pulley 25 is in pressure contact with the first transmission belt 23 and receives no power transmission. State. In this neutral state, the switching member 28 is not subjected to an operational reaction force against the tension of the first transmission belt 23, so that the switching member 28 and the electric motor 40 are removed from the support member 44 for maintenance work. Can be easily performed.

  The maintenance mode is set using the liquid crystal display unit 58. In the initial setting state, the liquid crystal display unit 58 displays various work information, such as the load state of the threshing device and the grain storage state, in the main display area 58A as shown in FIG. . Below the main display area 58A, a mode display area 58B and a mode switching command section 58C for commanding switching to the maintenance mode are provided.

  When the mode switching command unit 58C is operated, a maintenance mode switching confirmation screen is displayed as shown in FIG. 11B, and when the command unit 58D is operated, the maintenance mode is entered as shown in FIG. 11C. Switch. When the mode switching command unit 58C is operated again, the initial state is restored. As described above, the setting to the maintenance mode requires a plurality of operations, and switching to the maintenance mode is not performed due to an erroneous operation.

  After that, when the main switch 57 is operated to the start position and the engine start is commanded (step 8), the flag is set (maintenance mode) after the maintenance work is completed. If the operation position sensor 54 does not detect that the engine is in the neutral state, the engine 13 is prohibited from being started and maintained in a stopped state, and this is displayed on the liquid crystal display 58 serving as a notification means for notification. (Steps 9, 10, 11, 12). As the display of the liquid crystal display unit 58, for example, as shown in FIG. 12, notification information such as “Fan reverse rotation mechanism is not normally set” is displayed in the main display area. Then, it waits for the next engine start command.

  When the operation position sensor 54 detects that the engine is in the neutral state, the flag is reset, the cell motor 59 is operated, and the engine 13 is started (steps 13 and 14). Even when the flag is reset in step 9, the engine 13 is started (step 15).

[Another embodiment]
(1) In the above embodiment, when the maintenance mode is set, the operation of the engine 13 is stopped based on a manual operation. However, instead of this configuration, when the maintenance mode is set, the switching member After the electric motor 40 is controlled so that 28 is in the neutral position, the power supply to the control unit may be automatically stopped and the operation of the engine 13 may be automatically stopped.

(2) In the above embodiment, it is possible to switch to the maintenance mode even when the engine 13 is operating. Instead of this configuration, power is supplied to the control unit 56. In the state, the switch to the maintenance mode may be permitted on condition that the operation of the engine 13 is stopped.

(3) In the above embodiment, the potentiometer type operation position sensor 54 is used as the neutral state detection means. However, instead of this configuration, for example, a detection switch such as a limit switch may be used. In addition, for example, a pulse motor that rotates by a predetermined transfer with one pulse current may be used as the electric motor, and the neutral position may be detected based on the pulse count value from the start of operation. .

(4) In the above embodiment, when the restart is instructed after the operation of the engine 13 is stopped, if it is not detected that the engine is in the neutral state, the start process of the engine 13 is prohibited and a notification means for this is given. However, only the notification may be performed and the start of the engine 13 may be permitted, the start process of the engine 13 may be prohibited, and the notification by the notification unit may not be performed.

(5) In the above-described embodiment, the notification unit is configured by the liquid crystal display unit 58. However, as the notification unit, instead of the liquid crystal display unit 58, a display lamp is turned on or a buzzer is operated. For example, other notification means may be used.

(6) In the above embodiment, the switching member 28 is moved by an actuator (electric motor) to change the positions of the forward rotation pulley 24 and the reverse rotation pulley 25 integrally. However, two actuators are used. The forward rotation pulley 24 and the reverse rotation pulley 25 may be moved separately.

(7) In the above embodiment, the electric motor 40 is used as the actuator, but other devices such as an electric cylinder, a hydraulic motor, and a hydraulic cylinder may be used instead of the electric motor.

  The present invention can be applied not only to a combine but also to other types of work vehicles such as a tractor and a construction machine.

DESCRIPTION OF SYMBOLS 13 Engine 14 Engine bonnet 19 Radiator 20 Fan 22 Rotation state switching mechanism 23 Endless rotating body on driving side 24 Inner driven wheel body 25 Outer driven wheel body 26 Fan driving wheel body 27 Endless rotating body on driven side 40 Actuator 44 Support member 54 Neutral state detection means 56 Control unit 58 Notification means

Claims (5)

Switchable between a fan driven by engine power and passing cooling air through the radiator, a forward rotation state in which the fan is rotated in the forward rotation direction for cooling, and a reverse rotation state in which the fan is rotated in the reverse rotation direction for dust removal A rotation state switching mechanism,
The rotation state switching mechanism is
An endless rotating body on the driving side that is rotated by the power of the engine, an inner driven wheel body that is in contact with an inner peripheral surface of the endless rotating body on the driving side, and an outer driven wheel body that is in contact with the outer peripheral surface of the endless rotating body on the driving side The driven endless rotating body wound around each of the outer driven wheel body, the inner driven wheel body, and the fan driving wheel body, and the outer driven wheel body and the inner driven wheel body. And an actuator capable of changing the position,
A control unit for controlling the actuator is provided so that the control mode can be switched between a normal operation mode and a maintenance mode.
The controller is
In the normal operation mode, the forward driven state in which the inner driven wheel body is pressed against the driving endless rotating body and the outer driven wheel body is separated from the driving endless rotating body; and the outer driven wheel Controlling the operation of the actuator to alternately switch to the reverse state in which the body is pressed against the driving endless rotating body and the inner driven wheel body is separated from the driving endless rotating body;
In the maintenance mode, an operation for controlling the operation of the actuator so that both the inner driven wheel body and the outer driven wheel body are switched to a neutral state in which power is not transmitted from the endless rotating body on the driving side. Car engine cooling system. Neutral state detection means for detecting that the neutral state is provided,
The control unit is configured to control the operation of the engine, and in the maintenance mode, when the restart is instructed after the operation of the engine is stopped, the neutral state detection unit detects the neutral state. 2. The engine cooling device for a work vehicle according to claim 1, wherein the engine starting process is prohibited when it is not detected that the engine is detected.   The work according to claim 2, further comprising notification means for notifying that the neutral state is not detected by the neutral state detection means when the restart of the engine is instructed. Car engine cooling system. The rotation state switching mechanism includes a support member that supports the inner driven wheel body and the outer driven wheel body, respectively.
The actuator is configured to change the position of the outer driven wheel body and the inner driven wheel body integrally by moving the support member.
The engine cooling device for a work vehicle according to claim 2 or 3, wherein the neutral state detecting means is configured to detect the neutral state based on an operation position of the support member. An engine bonnet is provided that is switchable between a closed state that covers the top of the engine and an open state that opens the top of the engine,
The engine cooling device for a work vehicle according to any one of claims 1 to 4, wherein the rotation state switching mechanism is detachably attached to the engine bonnet.

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