CN106545400B - Engine cooling device for working vehicle - Google Patents

Abstract

The invention provides an engine cooling device of a working vehicle, which can easily perform maintenance operation such as repair and inspection of a rotating state switching mechanism. A control unit for controlling an actuator (40) is provided so as to be capable of switching a control mode between a normal operation mode and a maintenance mode, wherein the actuator (40) is capable of switching a fan (20) for ventilating cooling air to a radiator between a forward rotation state for rotationally driving the fan in a forward rotation direction for cooling and a reverse rotation state for rotationally driving the fan in a reverse rotation direction for removing dust, and wherein the control unit controls the operation of the actuator (40) so as to alternately switch between the forward rotation state and the reverse rotation state in the normal operation mode, and controls the operation of the actuator (40) so as to switch to a neutral state in which both an inner driven wheel body (24) and an outer driven wheel body (25) do not receive power transmission from a driving-side annular rotating body (23) in the maintenance mode.

Description

Engine cooling device for working vehicle

Technical Field

The present invention relates to an engine cooling device for a work vehicle, and more particularly, to an engine cooling device for a work vehicle including a fan that is driven by power of an engine and that ventilates cooling air to a radiator, and a rotational state switching mechanism that is capable of switching the fan between a forward rotational state in which the fan is rotationally driven in a forward rotational direction for cooling and a reverse rotational state in which the fan is rotationally driven in a reverse rotational direction for dust removal.

Background

The engine cooling device of the work vehicle cools the radiator by rotating the fan in the normal rotation state, and blows off dust attached to the dust removing portion of the radiator by switching the fan to the reverse rotation state. Further, conventionally, the rotation state switching mechanism is configured to include: a transmission belt (a driving-side endless rolling body) that rotates by power of an engine; a normal rotation pulley (one driven pulley body) that is in contact with an inner peripheral surface of the transmission belt; a reverse pulley (the other driven pulley) in contact with the outer peripheral surface; a driven-side belt (driven-side endless rotating body) wound around an input pulley of the fan; the operation of the electric motor is switched between a forward rotation state in which the forward rotation pulley is pressed against the transmission belt and a reverse rotation state in which the reverse rotation pulley is pressed against the transmission belt. (see, for example, patent document 1).

Patent document 1: japanese unexamined patent publication No. 2001-263063

In the above-described conventional configuration, the rotational state switching mechanism is configured to switch between the forward rotation state and the reverse rotation state, and therefore, the following disadvantages are present.

After the completion of the operation, when the rotation state switching mechanism is subjected to maintenance work such as repair and inspection, after the operation of the engine is stopped, the rotation state switching mechanism needs to be detached from the machine frame to perform the operation such as repair and inspection. That is, the rotation state switching mechanism includes a support portion for supporting the driven wheel body, an electric motor for moving and operating the driven wheel body, and an accompanying connection mechanism thereof, and these components need to be detached from the frame member on the machine side when maintenance work is performed.

However, even when such maintenance work is performed, the rotation state switching mechanism is maintained in a state in which the engine operation is stopped, which is one of the normal rotation state and the reverse rotation state, and therefore the driven wheel body (pulley) is in pressure contact with the transmission belt. Thus, if the driven sheave body is in pressure contact with the transmission belt, the driven sheave body receives a reaction force of the tension of the transmission belt. As a result, when each member of the rotation state switching mechanism is detached from the frame member on the machine side, the detachment work is difficult due to the reaction force received by the driven wheel body.

Therefore, it is desirable to facilitate maintenance work such as repair and inspection of the rotation state switching mechanism.

Disclosure of Invention

An engine cooling device for a work vehicle according to the present invention is characterized by comprising: a fan driven by the power of the engine and ventilating cooling air to the radiator; a rotational state switching mechanism capable of switching the fan between a forward rotational state in which the fan is rotationally driven in a forward rotational direction for cooling and a reverse rotational state in which the fan is rotationally driven in a reverse rotational direction for dust removal;

the rotation state switching mechanism includes: a ring-shaped rotating body on a driving side rotated by power of the engine; an inner driven wheel body connected to an inner peripheral surface of the annular rotating body on the driving side; an outer driven wheel body connected to the outer peripheral surface of the annular rotating body on the driving side; a driven-side annular rolling body wound around the outer driven wheel body, the inner driven wheel body, and the fan drive wheel body; an actuator capable of integrally performing a position changing operation on the outer driven wheel body and the inner driven wheel body;

the control section controlling the actuator is provided to freely switch the control mode between the normal operation mode and the maintenance mode,

in the normal operation mode, the control portion controls the operation of the actuator so as to alternately switch between the normal rotation state in which the inner driven wheel is pressed against the driving-side annular rolling element and the outer driven wheel body is separated from the driving-side annular rolling element and the reverse rotation state in which the outer driven wheel is pressed against the driving-side annular rolling element and the inner driven wheel body is separated from the driving-side annular rolling element,

in the maintenance mode, the control unit controls the operation of the actuator so as to switch to a neutral state in which both the inner driven wheel body and the outer driven wheel body do not receive power transmission from the annular rotating body on the driving side.

According to the present invention, when the work travel is performed, the control unit switches to the normal control mode and controls the operation of the actuator so as to alternately switch the fan between the forward rotation state in which the fan is rotationally driven in the forward rotation direction for cooling and the reverse rotation state in which the fan is rotationally driven in the reverse rotation direction for dust removal. After the completion of the work, the control unit switches to the maintenance mode during maintenance work such as repair and inspection. In the maintenance mode, the control unit controls the actuator to switch to a neutral state in which both the inner driven wheel body and the outer driven wheel body do not receive power transmission from the driving-side annular rotating body.

As a result, when each member of the rotation state switching mechanism is removed from the frame on the machine side for maintenance work, the driven wheel body is not subjected to a reaction force from the annular rotating body on the driving side, and the removal work is easily performed.

Therefore, maintenance work such as repair and inspection of the rotation state switching mechanism can be easily performed.

In the present invention, it is preferable that,

the engine cooling device for a work vehicle is provided with a neutral state detection means for detecting that the engine cooling device is in the neutral state,

the control unit is configured to control an operation of the engine, and is configured to prohibit a start-up process of the engine if the neutral state detection means does not detect that the engine is in the neutral state when a restart of the engine is instructed after the operation of the engine is stopped in the maintenance mode.

According to this configuration, in the maintenance mode, in a state where the engine operation is stopped, for example, each member in the rotation state switching mechanism is detached to perform maintenance work. After the maintenance work is finished, the components in the rotation state switching mechanism are assembled again.

When the maintenance work is performed, the state is switched to the neutral state in which both the inner driven wheel body and the outer driven wheel body do not receive the power transmission from the driving-side annular rotating body, but after the maintenance work is completed, there is a possibility that the assembly is performed in a state in which the mounting positions of the inner driven wheel body and the outer driven wheel body are shifted from the appropriate positions. In the case of such an improper assembly state, the neutral state detection means does not detect the neutral state, and therefore, even if the restart of the engine is instructed, the engine start processing is prohibited.

Therefore, after the maintenance operation is completed, the engine can be prevented from being directly operated in a state where the mounting positions of the inner driven wheel body and the outer driven wheel body are shifted from the appropriate positions.

In the present invention, it is preferable that,

the engine cooling device for a work vehicle is provided with a notification means for notifying, when a restart of the engine is instructed, if the neutral state detection means does not detect that the engine is in the neutral state.

According to this configuration, in the maintenance mode, when the engine is instructed to restart immediately after the completion of the maintenance operation, and the engine is not started, the notification mechanism performs the notification function, so that the operator can recognize that the mounting positions of the inner driven wheel body and the outer driven wheel body are shifted from the appropriate positions and the mounting is not performed appropriately.

Therefore, the operator can correct the mounting positions of the inner driven wheel body and the outer driven wheel body to appropriate positions by performing the assembly operation again immediately after the notification mechanism is operated.

In the present invention, it is preferable that,

the rotational state switching mechanism includes a support member that supports the inner driven wheel body and the outer driven wheel body,

the actuator is configured to move the support member to integrally change the position of the outer driven wheel body and the inner driven wheel body,

the neutral state detection means is configured to detect that the neutral state is present based on an operation position of the support member.

According to this configuration, the actuator moves the operation support member, so that the outer driven wheel body and the inner driven wheel body can be changed in position together, and the structure can be simplified as compared with a structure in which the outer driven wheel body and the inner driven wheel body are moved and operated separately. The neutral state detection means may detect the operation position of the support member, and the neutral state detection means can appropriately detect the neutral state while simplifying the structure.

In the present invention, it is preferable that,

the engine cooling device for a work vehicle is provided with an engine hood which can be freely switched between a closed state covering the upper part of the engine and an open state opening the upper part of the engine,

the rotation state switching mechanism is detachably attached to the engine cover.

According to this configuration, when the engine is operated to perform a normal operation, the upper side of the engine is covered with the engine cover in a closed state. On the other hand, when maintenance work such as repair and inspection of the engine is performed, the hood is switched to the open state, and the upper side of the engine is opened.

Since the rotating state switching mechanism is detachably attached to the hood, the rotating state switching mechanism can be detached from the hood when the hood is switched to the open state. That is, when the hood is in the closed state, the hood functions as a frame member on the body side and can support the rotation state switching mechanism. Further, when maintenance work around the engine is performed, the hood can be switched to the open state without the rotating state switching mechanism becoming an obstacle by detaching the rotating state switching mechanism from the hood.

Drawings

Fig. 1 is an overall side view of a combine harvester.

Fig. 2 is an overall plan view of the combine harvester.

Fig. 3 is a front view of the power section.

Fig. 4 is a vertical sectional side view of the switching operation portion.

Fig. 5 is a front view showing the rotation state switching mechanism.

Fig. 6 is a side view of the rotation state switching mechanism in the normal rotation state.

Fig. 7 is a side view of the rotational state switching mechanism in the inverted state.

Fig. 8 is a side view of the rotating state switching mechanism in the neutral state.

Fig. 9 is a control block diagram.

Fig. 10 is a flowchart of the control operation.

Fig. 11 is a diagram showing a display state of the liquid crystal display unit.

Fig. 12 is a diagram showing a notification display state.

Description of the reference numerals

13: engine

14: engine hood

19: heat radiator

20: fan with cooling device

22: rotation state switching mechanism

23: drive side ring rotator

24: inner driven wheel body

25: outer driven wheel body

26: wheel body for driving fan

27: driven side ring rotator

40: actuating mechanism

44: support member

54: neutral state detection mechanism

56: control unit

58: notification mechanism

Detailed Description

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 harvester as an example of a work vehicle will be described with reference to the drawings.

As shown in fig. 1 and 2, a combine harvester according to the present invention includes a harvesting unit 2 for harvesting standing straws in a front portion of a traveling machine body traveling by a pair of right and left crawler traveling devices 1, 1. The right side of the front part of the traveling machine body is provided with a driving part 4 whose periphery is covered by a driving cab 3, and the rear part of the traveling machine body is provided with a threshing device 5 which performs threshing processing on the grain stalks harvested by the harvesting part 2 and a grain bin 6 which stores grain obtained through the threshing processing. The driving unit 4 of the traveling machine body is provided with a power unit 8 in a state of being positioned below a driver seat 7, and an unloader 9 for discharging grains stored in the grain bin 6 to the outside of the machine.

In this embodiment, when the front-rear direction of the body is defined, the body forward direction in the working state is defined, and when the left-right direction of the body is defined, the left-right direction is defined in the state of being viewed in the body forward direction. That is, the direction indicated by the reference symbol (F) in fig. 1 and 2 is the front side of the machine body, and the direction indicated by the reference symbol (B) in fig. 1 and 2 is the rear side of the machine body. The direction indicated by the symbol (L) in fig. 2 is the left side of the body, and the direction indicated by the symbol (R) in fig. 2 is the right side of the body.

As shown in fig. 2, the cab 4 includes a cab seat 7, a front panel 10 positioned in front of the cab seat 7, a floor portion 11 positioned between the front panel 10 and the cab seat 7, a side panel 12 positioned on the lateral side of the cab seat 7 on the side of the reaping portion 2, and the like.

As shown in fig. 1, the engine cover 14 includes a front plate portion 14a positioned on the front side of the engine 13 in the machine body, an upper surface portion 14b positioned on the upper side of the engine 13 in the machine body, an intake chamber structure portion 14c formed behind the driver seat 7 in a state of being continuous to the rear of the upper surface portion 14b, and the like, and forms an engine chamber that opens inward in the machine body lateral direction and opens downward in the machine body. The driver seat 7 is supported on the upper portion of the upper surface portion 14 b. Further, an air cleaner 15 that purifies outside air and supplies combustion air to the engine 13 is provided inside the intake chamber structure portion 14c, and a strainer 16 that purifies outside air in advance and supplies the purified air to the air cleaner 15 is provided at an upper position of the right rear portion of the cab 3.

As shown in fig. 2, the hood 14, the front panel 10, the side panels 12, the floor 11, the operator's seat 7, the cab 3, and the like are integrally connected to form an operator structure 17. The cab structure 17 is supported by the body frame 18 to be rotatable about a vertical axis Y1 on the left rear side of the cab seat 7. The cab structure 17 is configured to be switchable between a normal use posture (a state shown by a solid line in fig. 2) in which the cab structure is retracted inward of the machine body and a maintenance posture (a state shown by a broken line in fig. 2) in which the cab structure is extended outward.

Although not shown in detail, the grain silo 6 is also supported by the machine body frame 18 so as to be rotatable about the rear vertical axis Y2, as in the case of the cab structure 17, and is configured so as to be switchable between a normal use posture (a state shown by a solid line in fig. 2) in which it is retracted inward of the machine body and a maintenance posture (a state shown by a broken line in fig. 2) in which it is extended outward. Further, the grain bin 6 can be switched to the maintenance posture in which the cab structure 17 is extended outward in a state switched to the maintenance posture.

As shown in fig. 3, the power unit 8 includes, in the engine cover 14: the engine 13, a radiator 19 for cooling the engine 13, and a fan 20 driven by power of the engine 13 and ventilating cooling air to the radiator 19 are provided with a dust screen 21 in a state of covering the entire surface of a communication opening with outside air provided on the lateral side surface of the engine hood 14.

The power unit 8 includes a rotational state switching mechanism 22 that can switch the fan 20 between a forward rotation state in which the fan is rotationally driven in a forward rotation direction for cooling and a reverse rotation state in which the fan is rotationally driven in a reverse rotation direction for dust removal. Next, the rotating state switching mechanism 22 will be described.

As shown in fig. 4 and 5, the rotating state switching mechanism 22 includes: a first belt 23 as a ring-shaped rotating body on a driving side rotated by the power of the engine 13; a normal rotation pulley 24 as an inner driven pulley body contacting an inner peripheral surface of the first transmission belt 23; a reverse pulley 25 as an outer driven pulley body contacting the outer peripheral surface of the first belt 23; a second belt 27 as a driven-side endless rotating body wound around the forward rotation pulley 24, the reverse rotation pulley 25, and the fan drive pulley 26 as a fan drive wheel body; a switching member 28 serving as a support member for supporting the forward rotation pulley 24 and the reverse rotation pulley 25, respectively; a switching operation part 29 for moving the switching member 28 to integrally change the positions of the forward pulley 24 and the reverse pulley 25.

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; a large-diameter driven gear 42 that is driven by meshing with a small-diameter output gear 41 driven by the electric motor 40; and a rotation operation member 43 that rotates integrally with the driven gear 42. The switching operation portion 29 is detachably attached to the engine hood 14.

The first belt 23 is wound around an idle pulley 31 rotatably supported by a rotary shaft 30, the output pulley 32 of the engine 13, and an input pulley 34 of an alternator 33, the rotary shaft 30 being supported by a side surface of the engine 13. A tension pulley 36 is supported at the tip of a tension arm 35 supported so as to be swingable around a horizontal shaft center P1 at the upper part of the casing of the alternator 33. Further, a spring 37 is provided for biasing the tension arm 35 toward the first belt 23. The tension pulley 36 is constantly pressed against the outer surface of the first belt 23 by the urging force of the spring 37, and a structure is formed to apply tension to the first belt 23.

The fan drive pulley 26 around which the second belt 27 is wound is fitted and supported to the rotary shaft 30 so as to be relatively rotatable. The base of the fan 20 is attached to the boss of the fan drive pulley 26. Therefore, the fan 20 and the fan drive pulley 26 rotate integrally.

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

As shown in fig. 6 to 8, the output pulley 32 of the engine 13 rotates in accordance with the operation of the engine 13, and the first belt 23 is driven in a state of always rotating in the direction of the arrow shown in the figure. When the switching member 28 is swung toward the normal rotation position a1 shown in fig. 6, the fan 20 is rotated in the normal rotation direction for cooling, and is driven in the normal rotation state. That is, the first contact portion 24a of the normal rotation pulley 24 presses the inner peripheral surface of the first transmission belt 23, the power of the first transmission belt 23 is transmitted as the normal rotation power to the input pulley 34 via the second contact portion 24b of the normal rotation pulley 24 and the second transmission belt 27, and the fan 20 is driven in the normal rotation in the clockwise direction shown in fig. 6.

When the fan 20 is driven in the normal rotation manner, a normal ventilation state is achieved, and in this ventilation state, the outside air flows as cooling air from the dust screen 21 to the engine 13 side through the radiator 19 by the suction action of the fan 20.

When the switching member 28 is swung to the reverse position a2 shown in fig. 7, the fan 20 is rotationally driven in the reverse direction for dust removal. That is, the first contact portion 25a of the reverse pulley 25 presses the outer peripheral surface of the first belt 23, the power of the first belt 23 is transmitted as the reverse power to the input pulley 34 via the second contact portion 25b of the reverse pulley 25 and the second belt 27, and the fan 20 is driven in reverse in the counterclockwise direction shown in fig. 7.

When the fan 20 is driven in reverse in this way, the blowing action of the fan 20 causes air to flow in a reverse manner to the normal ventilation state, and dust adhering to the surface of the radiator 19 and the dust screen is blown off.

When the switching member 28 is swung to the neutral position a3 shown in fig. 8, both the forward pulley 24 and the reverse pulley 25 are in a neutral state in which they are not pressed against the first transmission belt 23 and do not receive power transmission. This neutral state is a transmission state used when performing maintenance work such as inspection and repair of the rotational state switching mechanism 22.

Next, a mounting structure of the switching operation unit 29 will be explained.

The electric motor 40, the driven gear 42, and the rotational operation member 43 that rotates integrally therewith in the switching operation portion 29 are supported by a support member 44, respectively. As shown in fig. 4 and 5, the support member 44 includes an upper mounting plate 44A in a horizontal posture positioned on the upper side, a vertical plate portion 44B fixed to the lower side of the left and right intermediate portion of the upper mounting plate 44A and extending downward, and a reinforcement plate 44C provided between the mounting plate 44A and the vertical plate portion 44B in an inclined posture.

The housing 40a of the electric motor 40 is fixed to the vertical plate portion 44B by bolts, and the rotary shaft 40B of the electric motor 40 is inserted into the vertical plate portion 44B and projects to the opposite side, and the projecting portion of the rotary shaft 40B is provided with the output gear 41. The large-diameter driven gear 42 with which the output gear 41 is engaged is supported rotatably about the axis P2 of the fixed shaft 45 in the left-right direction on the fixed shaft 45, and the fixed shaft 45 is fixed to the side of the vertical plate portion 44B of the support member 44 opposite to the side where the electric motor 40 is disposed. A rotation operation member 43 that rotates integrally with the driven gear 42 is attached to one lateral surface of the driven gear 42.

The support member 44 is detachably attached to the engine hood 14. A pair of left and right mounting brackets 46 having a substantially L-shaped cross section are fixed to the lower surface side of the bottom portion of the intake chamber structure portion 35c in the engine hood 14 at a distance in the left-right direction, and a hood-side mounting plate 47 is provided in a state of being integrally fixed between the left and right mounting brackets 46. Four bolts 48 are fixed to the cover-side mounting plate 47 in a state of protruding downward.

Bolt insertion holes 49 into which four bolts 48 are inserted are formed in the upper mounting plate 44A of the support member 44. The upper mounting plate 44A is abutted against the lower surface side of the cover-side mounting plate 47 in a state where the four bolts 48 are inserted into the bolt insertion holes 49, respectively, and the support member 44 is attached to the engine hood 14 by connecting the bolts 48 and the nuts 50. By removing the four nuts 40, the support member 44 can be removed from the engine hood 14.

Of the four bolts 48 that connect the upper mounting plate 44A of the support member 44 to the cover-side mounting plate 47, three bolts 48 other than the front right-hand bolt 48a are welded and fixed to the cover-side mounting plate 47 in a state of protruding downward. The bolt 48a on the front right side is configured to be screwed to the cover-side mounting plate 47 in a detachable manner while being connected to the upper mounting plate 44A of the support member 44 by a nut 50. This is to avoid, for example, as shown in fig. 2, the bolts 48a on the front right side of the bolts 48 projecting downward from the cover-side attachment plate 47 from coming into contact with the pipe h of the intercooler 62 disposed outside the radiator 19 when the cab structure 17 is switched to the maintenance posture.

As shown in fig. 4, 6, and 7, a substantially fan-shaped winding member 51 that rotates integrally with the switching member 28 is provided, and the other end of the wire 52, one end of which is connected to the pin 43a provided on the rotation operation member 43, is connected to the pin 51a provided on the winding member 51. The winding member 51 is provided with a wire guide portion 51b, and the wire guide portion 51b guides the wire 52 in a wound state in which the wire is wound around the outer periphery of the rotary shaft 30 in an arc shape in accordance with the swing operation of the switching member 28. A pin 43b is provided at a position separated in the circumferential direction from the pin 43a for wire connection of the rotational operation member 43. A coil spring 53 as an operating member having a stroke absorbing function is stretched between 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 to rotate the rotational operation member 43 in the clockwise direction in fig. 4 toward the normal rotation position, the switching member 28 is rotated in the clockwise direction in conjunction with the coil spring 53. As shown in fig. 6, when the switching member 28 is positioned at an angle corresponding to the normal rotation position a1 and the first transmission belt 23 is in the normal rotation state in which the tension is appropriate for the tension, the pin 43b goes beyond the limit point, the tension applied via the coil spring 53 by the tension of the first transmission belt 23 is switched to a state in which the tension acts in the direction opposite to the above direction, that is, the direction of the rotational operation of the electric motor 40, and the electric motor 40 stops operating and is held in this state.

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

Subsequently, when the turning operation member 43 is rotated and driven by about 180 ° in the counterclockwise direction by the electric motor 40, the wire 52 is pulled, the switching member 28 is also swung in the counterclockwise direction, and the switching member 28 is swung to the reverse position a 2. Then, as shown in fig. 7, when the switching member is positioned at an angle corresponding to the reverse position and the reverse state is achieved in which the tension of the first belt 23 is appropriate, the pin 43a goes over the limit point, the tensile force applied via the coil spring 52 by the tension of the first belt 23 is switched to a state acting in the direction opposite to the previous direction, that is, the direction of the rotational operation of the electric motor 40, and the electric motor 40 stops operating, and the state is maintained.

In this case, when the switching member 28 is swung from the normal rotation position a1 to the reverse rotation position a2, the coil spring 53 is pulled toward the switching member 28 in association with the swinging of the switching member 28, but at the same time, the pin 43a of the swing operation member 43 to which the coil spring 53 is connected also moves toward the switching member 28, and therefore, the coil spring 53 does not become a large resistance against the swinging operation of the switching member 28 from the normal rotation position a1 to the reverse rotation position a 2. As described above, the electric motor 40 is operated to rotate in the forward and reverse directions, whereby the forward rotation state and the reverse rotation state can be alternately switched.

A potentiometer-type operating position sensor 54, which is an example of a neutral position detecting mechanism for detecting the swing operating position of the switching member 28, is provided on the lower side of the alternator 33. The operation position sensor 54 is configured to be linked by a link 55 between a swing end side of the operation arm 54b provided on the sensor body 54a so as to be swingable around the lateral axis P3 and a swing end side position of the switching member 28, and to output a detection value corresponding to a swing operation position of the switching member 28.

As shown in fig. 9, a control unit 56 using a microcomputer is provided for controlling the operation of the electric motor 40. Information detected by the operation position sensor 54 is input to the control unit 56. The disclosed device is provided with: a main switch 57 for turning on and off power supply to each electrical device; a touch panel type liquid crystal display unit 59 provided on the front panel 10 of the driver unit 4, capable of displaying various information and performing command operations; their information is also input to the control section 56. The control unit 56 controls the operation of the electric motor 40 based on the detection information of the operation position sensor 54, controls the operation of the engine 13 by controlling the operation of the starter motor 59 or the fuel cut valve 60, and further controls the operation of the liquid crystal display unit 58.

The main switch 57 is switchable between an off position for stopping power supply to each electrical device, an on position for performing power supply to each electrical device, and a start position for instructing start of the engine 13. When the main switch 57 is operated to the start position in the state of the engine stop operation, the control unit 56 operates the starter motor 59 to start the engine 13. When the main switch 57 is operated to the off position in the engine operating state, the power supply to each electrical device is stopped, and the control unit 56 operates the fuel cut valve 60 to stop the operation of the engine 13.

In the normal operation mode, the control unit 56 controls the operation of the electric motor 40 so as to alternately switch between the forward rotation state in which the switching member 28 is positioned at the forward rotation position a1, the first contact portion 24a of the forward rotation pulley 24 is brought into pressure contact with the first transmission belt 23, and the reverse rotation pulley 25 is separated from the first transmission belt 23, and the reverse rotation state in which the switching member 28 is positioned at the reverse rotation position a2, the first contact portion 25a of the reverse rotation pulley 25 is brought into pressure contact with the first transmission belt 23, and the forward rotation pulley 24 is separated from the first transmission belt 23.

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

In the maintenance mode, when a restart is instructed after the operation of the engine 13 is stopped, if the operating position sensor 54 does not detect that the engine 13 is in the neutral state, the control unit 56 is configured to display and notify the start processing of the engine 13 on the liquid crystal display unit 58 as notification means.

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 section 56 starts the control process. As shown in fig. 10, after 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 the fan 20 to the normal rotation state of the normal rotation drive, and after a predetermined time for the normal rotation (for example, several minutes or so), the switching member 28 is operated to the reverse rotation position a2 to switch the fan 20 to the reverse rotation state of the reverse rotation drive. Then, after a predetermined time (for example, several seconds) has elapsed from the switching to the reverse rotation state, the switching is performed again to the normal rotation state. The switching operation between the forward rotation state and the reverse rotation state is repeated, and the fan 20 is driven in reverse at predetermined time intervals to blow off dust adhering to the dust screen 21. When the main switch 57 is operated to the off position to command the engine stop, the fuel cut valve 60 is operated and the operation of the engine 13 is stopped (step 3).

When a worker operates the liquid crystal display unit 58 to instruct the maintenance mode in order to perform maintenance work on the rotating state switching mechanism 22, the operator sets a flag (steps 2 and 4) and operates the switching member 28 to the neutral position to control the operation of the electric motor 40 (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 operator 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. As shown in fig. 8, the neutral state in which the switching member 28 is at the neutral position a3 is a state in which both the forward rotation pulley 24 and the reverse rotation pulley 25 are not in pressure contact with the first transmission belt 23 and do not receive power transmission. In this neutral state, the switching member 28 is not subjected to an operation reaction force against the tension of the first transmission belt 23, and therefore, the operation of detaching the switching member 28 or the electric motor 40 from the support member 44 for maintenance can be easily performed.

The maintenance mode is set by the liquid crystal display unit 58. As shown in fig. 11(a), the liquid crystal display unit 58 displays various information for work, for example, a load state of the threshing device, a grain storage state, and the like, in an initial setting state in the main display area 58A. A mode display area 58B and a mode switching command unit 58C that commands switching to the maintenance mode are provided below the main display area 58A.

When the mode switching instruction unit 58C is operated, a screen for confirming switching to the maintenance mode is displayed as shown in fig. 11(b), and when the instruction unit 58D is operated, the mode is switched to the maintenance mode as shown in fig. 11 (C). When the mode switching command unit 58C is operated again, the initial state is returned. In this way, the setting to the maintenance mode requires several operations, and the switching to the maintenance mode is not performed due to an erroneous operation.

Thereafter, when the main switch 57 is operated to the start position to instruct the engine to start (step 8), and at this time, when the maintenance work is completed and the flag is set (in the maintenance mode), if the neutral state is not detected by the operation position sensor 54, the start processing of the engine 13 is prohibited and the stopped state is maintained, and this is displayed on the liquid crystal display unit 58 as the notification means and notified ( steps 9, 10, 11, and 12). As the display of the liquid crystal display unit 58, for example, as shown in fig. 12, a notification message "the fan reversing mechanism is not normally installed" is displayed in the main display area. Then, the next engine start command is waited for.

When the neutral state is detected by the operation position sensor 54, the flag is reset, and the starter motor 29 is operated to start the engine 13 (steps 13 and 14). Even in the case where the flag is reset in step 9, the engine 13 is started (step 15).

[ other embodiments ]

(1) In the above embodiment, the operation of the engine 13 is stopped by manual operation when the maintenance mode is set, but instead of this configuration, the electric motor 40 may be controlled to set the switching member 28 to the neutral position when the maintenance mode is set, and then 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, the switching to the maintenance mode is possible even in a state where the engine 13 is operating, but instead of this configuration, the switching to the maintenance mode may be permitted on condition that the operation of the engine 13 is stopped in a state where the power is supplied to the control unit 56.

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

(4) In the above embodiment, when the restart of the engine 13 is instructed after the operation stop, if the neutral state is not detected, the start-up process of the engine 13 is prohibited and the notification means notifies the start-up of the engine 13.

(5) In the above embodiment, the configuration in which the notification means is constituted by the liquid crystal display unit 58 is shown, but other notification means such as lighting a display lamp or operating a buzzer may be used as the notification means instead of the liquid crystal display unit 58.

(6) In the above embodiment, the switching member 28 is moved by the actuator (electric motor) to integrally change the position of the forward pulley 24 and the reverse pulley 25, but the forward pulley 24 and the reverse pulley 25 may be moved by two actuators.

(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 is not limited to the combine harvester, and can be applied to other types of work vehicles such as tractors and construction machines.

Claims (8)

1. An engine cooling device for a working vehicle, comprising: a fan (20) that is driven by the power of the engine (13) and that ventilates cooling air to the radiator (19); a rotational state switching mechanism (22) capable of switching the fan (20) between a forward rotational state in which the fan is rotationally driven in a forward rotational direction for cooling and a reverse rotational state in which the fan is rotationally driven in a reverse rotational direction for dust removal;

the rotating state switching mechanism (22) is provided with: a drive-side annular rolling body (23) that rotates by the power of the engine (13); an inner driven wheel body (24) that is in contact with the inner peripheral surface of the drive-side annular rolling body (23); an outer driven wheel body (25) that is in contact with the outer peripheral surface of the drive-side annular rolling body (23); a driven-side annular rolling body wound around the outer driven wheel body (25), the inner driven wheel body (24), and the fan driving wheel body (26); an actuator (40) capable of integrally performing a position changing operation on the outer driven wheel body (25) and the inner driven wheel body (24);

a control unit (56) for controlling the actuator (40) is configured to freely switch a control mode between a normal operation mode and a maintenance mode,

when switching to the normal operation mode, the control unit (56) controls the operation of the actuator (40) so as to alternately switch between a normal rotation state in which the inner driven wheel body (24) is brought into contact with the driving-side annular rolling body (23) and the outer driven wheel body (25) is separated from the driving-side annular rolling body (23), and a reverse rotation state in which the outer driven wheel body (25) is brought into contact with the driving-side annular rolling body (23) and the inner driven wheel body (24) is separated from the driving-side annular rolling body (23),

when the maintenance mode is switched, the control unit (56) controls the operation of the actuator (40) so as to switch to a neutral state in which both the inner driven wheel body (24) and the outer driven wheel body (25) do not receive power transmission from the driving-side annular rotating body (23), and so as to maintain the operation of the actuator before switching to the normal operation mode is instructed.

2. The engine cooling apparatus for a work vehicle according to claim 1,

the engine cooling device of the working vehicle is provided with a neutral state detection mechanism (54) for detecting that the working vehicle is in the neutral state,

the control unit (56) is configured to control the operation of the engine (13), and is configured to prohibit a starting process of the engine (13) if the neutral state detection means (54) does not detect that the engine (13) is in the neutral state when a restart of the engine (13) is instructed after the operation stop in the maintenance mode.

3. The engine cooling apparatus for a work vehicle according to claim 2,

the engine cooling device for a working vehicle is provided with a notification means (58), and when the engine (13) is instructed to restart, if the neutral state detection means (54) does not detect that the engine is in the neutral state, the notification means (58) notifies that fact.

4. The engine cooling apparatus for a working vehicle according to claim 2 or 3,

the rotational state switching mechanism (22) is provided with a support member (44) that supports the inner driven wheel body (24) and the outer driven wheel body (25), respectively,

the actuator (40) is configured to move the support member (44) to integrally change the position of the outer driven wheel body (25) and the inner driven wheel body (24),

the neutral state detection means (54) is configured to detect that the neutral state is present based on an operation position of the support member (44).

5. The engine cooling apparatus for a work vehicle according to claim 4,

the engine cooling device for a work vehicle is provided with an engine cover (14) which can freely switch the posture between a closed state covering the upper part of the engine (13) and an open state opening the upper part of the engine (13),

the rotational state switching mechanism (22) is detachably attached to the engine cover (14).

6. The engine cooling device for a working vehicle according to any one of claims 1 to 3,

the engine cooling device for a work vehicle is provided with an engine cover (14) which can freely switch the posture between a closed state covering the upper part of the engine (13) and an open state opening the upper part of the engine (13),

the rotational state switching mechanism (22) is detachably attached to the engine cover (14).

7. The engine cooling apparatus for a work vehicle according to claim 5,

the support member (44) is detachably attached to the engine cover (14).

8. The engine cooling apparatus for a work vehicle according to claim 7,

a pair of left and right mounting brackets (46) are fixed to the lower surface side of the engine cover (14), and a cover-side mounting plate (47) is provided on the mounting brackets (46),

the support member (44) is provided with an upper mounting plate (44A),

the support member (44) is attached to the engine hood (14) by connecting the hood-side attachment plate (47) and the upper attachment plate (44A).

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