JP2016050518A - Prime mover for service vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable an operation to be started after dust adhered to a filter body is blown out when an engine is started again, enable an output of the engine to be improved and operation efficiency to be improved.SOLUTION: A cooling fan [20] and a dust discharging fan [30] of which blade angles are set in opposition values are rotatably arranged on the same central axis between an engine [E] and a radiator [50]. There are provided a cooling clutch [C1] for connecting or disconnecting a transmission of driving force from the engine [E] to a cooling fan [20] and a dust discharging clutch [C2] for connecting or disconnecting a transmission of driving force from the engine [E] to the dust discharging fan [30]. There is provided a driving state changing-over means [45] to be controlled under interval state to connect the cooling clutch [C1] and the dust discharging clutch [C2] alternatively under a prescribed time interval. When the engine [E] is started to operate, the interval control is started from the connection with the dust discharging clutch [C2].SELECTED DRAWING: Figure 10

Description

  The present invention relates to a prime mover for a working vehicle that removes dust and dust adhering to a filter installed outside a radiator and prevents engine overheating.

  Conventionally, a water-cooled engine is used in a work vehicle such as a combine. The cooling water whose temperature has been raised by the engine is cooled by circulating through the radiator, and then circulates through the engine again.

  Combine is a process of harvesting, threshing, sorting, and rejecting cereals, and the front reaping device generates swarf and dust by cutting and transporting napped cereals, and threshing from the rear. Since the waste and dust generated by the waste cutting process after threshing are discharged, a large amount of waste and dust are wound around the combine body. If the wound sawdust etc. adhere to the filter body mounted on the cover of the engine room and these filter bodies are clogged, it will not be possible to inhale sufficient outside air from the outside of the filter body to the inside, The cooling efficiency of the radiator decreases, and in some cases, the engine may overheat.

  In order to solve the above problem, Patent Document 1 discloses that the rotation direction of the fan provided inside the radiator is switched by moving the tension operation body, cooling the radiator, and the dust attached to the filter body cover of the engine room. A configuration for removing dust and the like has been proposed.

  In addition, when the outside air temperature is low, there is a problem that the engine output is reduced when the engine is started, and the work efficiency is lowered. For this reason, conventionally, the operation is started after the warm-up operation is performed after the engine is started.

Japanese Patent Laid-Open No. 2001-263063

  However, in the configuration disclosed in Patent Document 1, the exhaust ability of the outside air to the outside of the engine room in the reverse direction of the fan is lower than the intake ability of the outside air to the inside of the engine room in the forward direction of the fan. Therefore, the dust, dust, etc. adhering to the filter attached to the engine room cover cannot be removed sufficiently, and the filter is clogged with the dust, dust, etc. that cannot be removed, and the cooling efficiency of the radiator is increased. As a result, the engine was overheated.

  In addition, when the work is completed while the fan is rotating forward and the engine is stopped, the fan starts rotating forward when the engine is restarted to resume the work. As a result, the fan starts normal rotation while leaving the dust and dust adhering to the filter body at the end of work, and the filter body is likely to be clogged at the start of work, and the cooling efficiency of the radiator is reduced. Therefore, there is a problem that the engine output decreases and the work efficiency of the work vehicle decreases.

Further, conventionally, when the outside air temperature is low, the output of the engine is reduced, so that it is necessary to perform a warm-up operation before starting work, and there is a problem that work efficiency is lowered.
Therefore, the main problem of the present invention is to eliminate such problems.

The present invention that has solved the above problems is as follows.
According to the first aspect of the present invention, the radiator (50) is disposed outside the engine (E), the filter body (8B) for filtering dust is disposed outside the radiator (50), and the engine (E). And a radiator (50), a cooling fan (20) and a dust exhaust fan (30), whose blade angles are set opposite to each other, are rotatably provided on the same axis, and the cooling fan from the engine (E) is provided. A cooling clutch (C1) that connects and disconnects transmission of driving force to (20), and a dust clutch (C2) that connects and disconnects transmission of driving force from the engine (E) to the dust exhaust fan (30). Provided with drive state switching means (45) that is interval-controlled so as to alternately connect the cooling clutch (C1) and the dust removal clutch (C2) at predetermined time intervals, and at the time of starting the engine (E), Dust removal clutch ( 2) is from the connection that the driving unit of a working vehicle having a configuration in which the interval control is started.

  The invention according to claim 2 is the driving part of the working vehicle according to claim 1, wherein the connection time relationship between the cooling clutch (C1) and the dust exhaust clutch (C2) in the interval control can be changed. It is.

  According to a third aspect of the present invention, both the cooling clutch (C1) and the dust exhaust clutch (C2) are alternately connected at predetermined time intervals, and both the cooling fan (C1) and the dust exhaust clutch (C2) are connected. The driving part of the working vehicle according to claim 1, wherein the driving part can be switched to a state in which the engine is shut off.

  The invention according to claim 4 includes a water temperature sensor (50T) for detecting the temperature of the cooling water of the radiator (50), and the cooling water temperature detected by the water temperature sensor (50T) is lower than a set temperature. 4. The driving portion of the working vehicle according to claim 3, further comprising a control device (U) that automatically shuts off both the cooling clutch (C1) and the dust removal clutch (C2).

  According to a fifth aspect of the present invention, when it is detected that the cooling water temperature detected by the water temperature sensor (50T) has risen to a temperature equal to or higher than a preset temperature, the cooling clutch (C1) is automatically connected. According to a fourth aspect of the present invention, there is provided a driving part of the working vehicle according to claim 4.

  The invention according to claim 6 includes an exhaust temperature sensor (GP) for detecting the temperature of the exhaust gas of the engine (E), and the exhaust temperature detected by the exhaust temperature sensor (GP) is lower than a set temperature. In this case, the driving portion of the working vehicle according to claim 3 is provided with a control device (U) that automatically shuts off both of the cooling clutch (C1) and the dust removal clutch (C2).

  According to a seventh aspect of the present invention, when the exhaust temperature sensor (GP) provided in the exhaust path of the engine (E) detects that the exhaust temperature has risen to a temperature equal to or higher than a set exhaust temperature, the cooling is performed. The working portion of the working vehicle according to claim 6, wherein the clutch (C1) is automatically connected.

  According to an eighth aspect of the present invention, when the cooling clutch (C1) and the dust removal clutch (C2) are alternately connected at a predetermined time interval, a predetermined time is elapsed after the cooling clutch (C1) is disconnected. In this case, the working portion of the working vehicle according to claim 1 is configured to be connected to the dust clutch (C2).

  According to the first aspect of the present invention, the interval control in which the cooling clutch (C1) and the dust removal clutch (C2) are alternately connected and disconnected at a predetermined time interval is performed, and the cooling provided on the same axis is performed. Since the fan (20) and the dust exhaust fan (30) rotate alternately, the dust attached to the filter body (8B) is blown off by the dust exhausted air by the dust exhaust fan (30), and then the cooling fan (20) is used. The intake efficiency of the intake air can be increased and the engine (E) can be prevented from overheating. At this time, by providing the cooling fan (20) and the dust exhaust fan (30) on the same axis, the diameters of both fans (20, 30) can be increased and the blowing power can be increased.

  When the engine (E) is restarted after the engine (E) is stopped while the cooling fan (20) is rotating, the dust exhaust fan (30) connected by the dust clutch (C1) is connected. Since the interval control is started from the rotation, the work can be resumed after the dust attached to the filter body (8B) is blown off, the cooling efficiency of the engine (E) is increased, the output of the engine (E) is improved, Work efficiency can be increased.

  According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, in the interval control described above, depending on the state of dust adhering to the filter body (8B) due to the difference in work conditions. The rotation time relationship between the cooling fan (20) and the dust exhaust fan (30) can be changed to maintain the output of the engine (E).

  According to the third aspect of the present invention, in addition to the effect of the first aspect of the invention, the cooling fan (C1) and the dust clutch (C2) are shut off and the cooling fan (20) and the dust fan ( By stopping the rotation of 30), the water temperature of the radiator (50) rises early, the engine (E) can be warmed up efficiently, the output of the engine (E) is increased, and the work of the work vehicle Efficiency can be improved.

  According to the invention described in claim 4, in addition to the effect of the invention described in claim 3, when the temperature of the cooling water of the radiator (50) is lower than the set temperature, the cooling clutch (C1) and the dust discharge Since both clutches (C2) are automatically disconnected and transmission of driving force to the cooling fan (20) and the dust exhaust fan (30) stops, the water temperature of the radiator (50) rises to an appropriate temperature at an early stage. The combustion efficiency in the engine (E) can be increased, the output of the engine (E) can be increased, and the working efficiency of the work vehicle can be increased.

  According to the invention described in claim 5, in addition to the effect of the invention described in claim 4, the cooling clutch (C1) is automatically connected when the cooling water temperature of the radiator (50) rises above the set temperature. Since the cooling fan (20) rotates, it is possible to prevent a decrease in combustion efficiency due to overheating of the engine (E), to reduce a decrease in output of the engine (E), and to prevent a decrease in work efficiency of the work vehicle.

  According to the invention described in claim 6, in addition to the effect of the invention described in claim 3, when the temperature of the exhaust gas of the engine (E) is lower than the set temperature, the cooling clutch (C1) and the dust Since both clutches (C2) are automatically disconnected and transmission of driving force to the cooling fan (20) and the dust exhaust fan (30) is stopped, the gas combustion temperature of the engine (E) reaches an appropriate temperature early. As a result, the combustion efficiency in the engine (E) is increased, the output of the engine (E) is increased, and the working efficiency of the work vehicle can be increased.

  According to the invention of claim 7, in addition to the effect of the invention of claim 6, when the temperature of the exhaust gas of the engine (E) rises above the set temperature, the cooling clutch (C1) is automatically activated. Since the cooling fan (20) rotates, the combustion efficiency can be prevented from being lowered due to overheating of the engine (E), and the output of the engine (E) can be prevented from being lowered, thereby preventing the working efficiency of the work vehicle from being lowered. .

  According to the invention described in claim 8, in addition to the effect of the invention described in claim 1, the dust clutch (C2) is connected after a predetermined time has elapsed after the cooling clutch (C1) is disconnected. Therefore, since the dust exhaust fan (30) rotates after the rotation due to the inertia of the cooling fan (20) is stopped or decelerated, the dust exhaust fan (30) is sucked by the intake of outside air by the rotation of the cooling fan (20). The blow-out of the inside air due to is less likely to be hindered, and the dust attached to the filter body (8B) can be effectively removed.

It is a right view of a combine. It is a top view of a combine. It is a principal part rear view of an engine room. It is a principal part left view of an engine room. It is a principal part right view of an engine room. It is a principal part right view of the periphery of a drive state switching means. It is a principal part rear view around a radiator fan and a dust exhaust fan. It is a principal part left side view of the 1st and 2nd tension roller periphery. (A) is the principal part rear view of the state which has been biased and arranged in the engine side, and (b) is the biased arrangement in the opposite side of the engine. It is a transmission diagram. It is a right view of an engine and an oxidation catalyst device. It is a top view of an engine and an oxidation catalyst device. It is a rear view of an engine and an oxidation catalyst device. It is a left view of an engine and an oxidation catalyst device. It is a block diagram of a control apparatus.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. For the sake of easy understanding, the explanation is given with the direction shown for the sake of convenience with the front as the front, the rear as the rear, the right hand side as the right side, and the left hand side as the left side, as viewed from the operator boarding the cockpit. However, the configuration is not limited by these.

  As shown in FIGS. 1 and 2, the combine is provided with a traveling device 2 composed of a pair of left and right crawlers below the machine frame 1, and on the upper left side of the machine frame 1 is a threshing device 3 that performs threshing and sorting. Is provided, and on the front side of the threshing device 3, a reaping device 4 for harvesting cereals in the field is provided. The grains threshed and selected by the threshing apparatus 3 are stored in a Glen tank 5 provided on the right side of the threshing apparatus 3, and the stored grains are discharged to the outside by the discharge cylinder 7.

  On the upper right side of the fuselage frame 1, a cockpit 6 including an operation unit on which an operator gets on is provided. Below the cockpit 6, an engine room 8 on which an engine E is mounted is provided. Further, a cover 8A for maintenance / inspection of the engine room 8 is mounted on the right side of the engine room 8, and a filter body formed of a steel plate or the like is formed at the middle and lower parts of the cover 8A in the vertical direction. 8B is attached.

  As shown in FIGS. 3 to 5, an engine E is provided inside the engine room 8. An exhaust pipe connected to the exhaust head of the engine E is provided with an exhaust temperature sensor GP for detecting the exhaust temperature. As shown in FIGS. 11 to 14, an oxidation catalyst device 11 such as a DOC that oxidizes unburned fuel in exhaust gas discharged from the engine E is provided on the upper left side of the engine E. Thereby, the inside air heated by the oxidation catalyst device 11 can be efficiently blown toward the threshing device 3, and drying of the threshing grains in the threshing device 3 can be promoted. The oxidation catalyst device 11 is detachably attached to a stay 11B provided on the upper left side of the engine E by two front and rear support members 11A. The exhaust gas temperature sensor GP may be attached to the oxidation catalyst device 11 to detect the temperature inside the oxidation catalyst device 11. The oxidation catalyst device 11 may be provided with a DPF (Diesel Particulate Filter) having a filter for filtering particulate matter in the exhaust gas flow direction. It is good also as a structure which detects internal temperature.

  On the right side of the engine E, there is provided a radiator 50 that cools cooling water supplied to the engine E at a predetermined interval. A rubber radiator hose 50A that connects the engine E and the radiator 50 is provided in the engine room 8. It is provided at the same height as the oxidation catalyst device 11. Thereby, it is not necessary to provide the radiator hose 50 </ b> A in the space between the engine E and the radiator 50, and a large space can be secured between the engine E and the radiator 50. The radiator 50 is provided with a water temperature sensor 50T that detects the temperature of the cooling water.

  Between the engine E and the radiator 50, a radiator fan (cooling fan) 20 that sucks outside air from the outside of the engine room 8 to the inside, and a left side of the radiator fan 20, from the inside of the engine room 8 to the outside A dust exhaust fan 30 is provided to exhaust the inside air and remove dust adhering to the filter body 8B.

  When the radiator fan 20 rotates, the cooling efficiency of the radiator 50 can be increased by sucking outside air into the engine room 8 through the filter body 8B of the cover 8A and blowing it to the surface of the radiator 50 or the like. . Further, when the dust exhaust fan 30 rotates, the inside air is exhausted to the outside through the filter body 8B of the cover 8A, and the inside air is blown to the filter body 8B, thereby removing dust attached to the filter body 8B. Thus, the efficiency of the outside air suction by the radiator fan 20 can be kept constant. For convenience, the rotation of the radiator fan 20 and the dust exhaust fan 30 is referred to as a drive state, and the stop of the rotation of the radiator fan 20 and the dust exhaust fan 30 is referred to as a stop state.

  The radiator fan 20 is formed of a central portion attached to the rotary shaft 24 and blades extending in the radial direction from the central portion. In this embodiment, eight blades are provided at a predetermined interval in the circumferential direction of the central portion in order to increase the efficiency of sucking outside air by the radiator fan 20. It can be changed to the number of sheets.

  Similarly, the dust exhaust fan 30 is formed of a central portion attached to the cylindrical rotary shaft 34 and blades extending from the central portion in the radial direction. In order to prevent a reduction in outside air suction efficiency by the radiator fan 20, the outer diameter of the blades of the dust exhaust fan 30 is formed smaller than the outer diameter of the blades of the radiator fan 20. Further, in order to simplify the transmission configuration of the radiator fan 20 and the dust exhaust fan 30 and to effectively use the space in the engine room 8, the blade angle of the blade of the dust fan 30 is the blade blade of the radiator fan 20. It is erected at the center with a blade angle opposite to the angle. Thereby, even if the rotation direction transmitted to the cylindrical rotating shaft 34 to which the dust exhaust fan 30 is attached and the rotation direction transmitted to the rotation shaft 24 to which the radiator fan 20 is attached are the same rotation direction, the radiator. The fan 20 can suck outside air and blow it to the inside of the engine room 8, and the dust exhaust fan 30 can exhaust the inside air to the outside of the engine room 8. In addition, although eight blades of the dust exhaust fan 30 are provided at predetermined intervals in the circumferential direction of the central portion, any number can be set within a range in which a desired air blowing capacity can be obtained.

  Between the radiator 50 and the cover 8A, an oil cooler 51 that cools oil supplied to a hydraulic cylinder that moves up and down the reaping device 4 and an intercooler 52 that cools a combustion gas mixture supplied to the engine E are provided. It has been.

  The front part of the oil cooler 51 is attached to the front part of the plate 1F via the butterfly 53, and the rubber hose 54 connecting the oil cooler 51 and the hydraulic cylinder is in an opening 55 formed in the plate 1G. It is inserted. Thereby, at the time of maintenance / inspection work of the radiator 50, the oil cooler 51 can be rotated by the butterfly 53, and the right side of the radiator 50 can be opened to easily perform maintenance / inspection of the radiator 50.

  The upper and lower portions of the intercooler 52 are respectively attached to the plate 1F via support members 56, and a metal pipe 57A located on the right side of the plate 1F connecting the intercooler 52 and the engine E is formed on the plate 1G. It is fixed to the outer periphery of the opening 58.

  Further, the metal pipe 57 </ b> B located on the left side of the plate 1 </ b> F connecting the intercooler 52 and the engine E is provided at the same height as the oxidation catalyst device 11 in the engine room 8. Thereby, it is not necessary to provide the pipe 57B in the space between the engine E and the radiator 50, and a large space can be secured between the engine E and the radiator 50.

  The plate 1F is attached to the right front frame 1A and the right rear frame 1B of the frames 1A to 1D that support the cockpit 6 via support members 59A. Similarly, the plate 1G is attached to the right front frame 1A and the right rear frame 1B via support members 59B.

  As shown in FIG. 10, the rotational power of the engine E is transmitted to the crankshaft 60 extending from the engine E toward the right side, and the rotational power transmitted to the crankshaft 60 is a pulley 61, a belt 62, and a pulley 63. Is transmitted to the rear transmission shaft 110 that supports the pulley 63.

  A water pump shaft 60A positioned above the crankshaft 60 of the engine E instead of the crankshaft 60, an alternator shaft 60D positioned on the upper left side of the crankshaft 60, and a fly extending from the engine E toward the left side. The rotational power transmitted to the wheel shaft 60B can be transmitted to the rear transmission shaft 110 via a pulley, a belt, or the like. A belt 60E is wound around a pulley that is supported by the crankshaft 60, the water pump shaft 60A, and the alternator shaft 60D, and the rotational power of the crankshaft 60 is transmitted through the belt 60E to the water pump. It is transmitted to shaft 60A and alternator shaft 60D.

  The rotational power transmitted to the rear transmission shaft 110 is a rotation that supports the pulley 23 via a pulley 121, a belt (“first belt” in claims) 122, and a pulley (“third pulley” in claims) 23. The radiator fan 20 that is transmitted to the shaft 24 and supported by the right end of the rotating shaft 24 is rotated.

  Similarly, the rotational power transmitted to the rear transmission shaft 110 passes through the pulley 131, the belt (“second belt” in claim) 132, and the pulley (“fourth pulley” in claim) 33. The dust exhaust fan 30, which is transmitted to the supporting cylindrical rotating shaft 34 and supported at the right end of the cylindrical rotating shaft 34, is rotated. The rotating shaft 24 is fitted inside the support portion 25 via a bearing, and the cylindrical rotating shaft 34 is fitted outside the support portion 25 via a bearing.

  The belt 122 wound around the pulley (the “first pulley” in the claims) 121 and the pulley 23 is provided with a tension roller 26. The tension roller 26 changes the tension of the belt 122 to transmit the rotational power. Connect and disconnect. That is, the belt 122 and the tension roller 26 constitute a cooling clutch C1 for the radiator fan 20 that connects and disconnects power transmission. Further, the belt 132 and the tension roller 36 constitute a dust clutch C2 for the dust fan 30 that connects and blocks power transmission.

  Similarly, the pulley 132 (the “second pulley” in the claims) 131 and the belt 132 wound around the pulley 33 are provided with a tension roller 36, and the tension roller 36 changes the tension of the belt 132 to rotate the power. Connect and shut off the transmission.

  The belt 122 that transmits rotational power to the radiator fan 20 is provided closer to the engine E than the belt 132 that transmits rotational power to the dust exhaust fan 30. Thus, maintenance / inspection work of the belt 122 that deteriorates earlier than the belt 132 due to a long driving time can be easily performed.

  Further, the rotational power transmitted to the rear transmission shaft 110 is transmitted to a shaft 71 extending rearward from the transmission gear box 70 through a transmission gear box 70 having a pair of opposed bevel gears.

  The rotational power transmitted to the shaft 71 is transmitted to the discharge spiral shaft 75 that supports the pulley 74 via the pulley 72, the belt 73, and the pulley 74. The discharge spiral shaft 75 is provided in the lower part of the Glen tank 5 so as to extend in the front-rear direction, and transfers the grains stored in the Glen tank 5 to the discharge cylinder 7 and is a spiral built in the discharge cylinder 7. Drive the shaft. The belt 73 wound around the pulley 72 and the belt 73 is provided with a tension roller (not shown), and the tension of the belt 73 is changed by the tension roller to connect and disconnect the transmission of the rotational power.

  In the present specification, the intermediate transmission unit 150 refers to a part composed of the pulley 61, the belt 62, the pulley 63, the rear transmission shaft 110, the pulley 121, the pulley 131, the transmission gear box 70, the shaft 71, and the pulley 72. The fan transmission unit 160 includes a belt 122, a tension roller 26, a pulley 23, a rotating shaft 24, a radiator fan 20, a belt 132, a tension roller 36, a pulley 33, a cylindrical rotating shaft 34, and a dust exhaust fan 30. The discharge transmission part 170 is a part composed of the belt 73, the pulley 74, and the discharge spiral shaft 75.

  As shown in FIGS. 3 to 5, the intermediate transmission unit 150 is provided in the rear part of the engine room 8. The pulley 63, the rear transmission shaft 110, the pulley 121, the pulley 131, the transmission gear box 70, the shaft 71, and the pulley 72 of the intermediate transmission unit 150 are located behind the right rear frame 1B and the left rear frame 1D in a side view. In addition, it is provided in the space S on the front side of the front wall 5A of the Glen tank 5.

  The belt 122, the tension roller 26, the pulley 23, the belt 132, the tension roller 36, and the pulley 33 of the fan transmission unit 160 are disposed on the right side of the engine E and on the left side of the radiator fan 20. It is provided in the space B on the left side of the screen. That is, the fan transmission unit 160 is provided so as to enter the space B from the intermediate transmission unit 150 provided on the rear side of the engine room 8.

  Thereby, the parts provided in the space | interval part B can be decreased, the engine E and the radiator fan 20 can be provided close, and the engine E can be cooled efficiently with the external air suck | inhaled by the radiator fan 20.

  Further, the crankshaft 60 of the engine E and the pulley 63 of the intermediate transmission unit 150 can be provided close to each other, and the transmission loss of the rotational power caused by the belt 62 can be reduced.

Further, maintenance and inspection work of the intermediate transmission unit 150 can be easily performed, and the intermediate transmission unit 150 can be manufactured to be small and light.
Next, the driving state switching means 45 that switches the driving states of the radiator fan 20 and the dust exhaust fan 30 will be described.

  As shown in FIG. 6 and the like, the drive state switching means 45 is provided on the rear side of the left rear frame 1D located on the left rear side of the engine room 8. More specifically, the drive state switching means 45 supports a reservoir tank 92 that temporarily stores a part of the cooling water circulating through the engine E and the radiator 50 extending from the left rear frame 1D toward the rear side. The bracket 91 is detachably connected to the upper portion of the stay 90 by a fastening means such as a bolt. Thereby, the maintenance / inspection work of the drive state switching unit 45 can be easily performed, and the drive state switching unit 45 can be prevented from obstructing the ventilation of the radiator fan 20 and the dust exhaust fan 30.

  The bracket 91 is coupled to the stay 90 by fastening together using a fastening means for supporting the reservoir tank 92 to the stay 90, and the drive state switching means 45 is attached to the left side surface of the bracket 91 on the side opposite to the reservoir tank 92. Installed. Thereby, the number of parts can be reduced, and it is possible to prevent the drive state switching means 45 from being damaged by the cooling water splashed from the reservoir tank 92 when the reservoir tank 92 is damaged.

  A substantially rectangular plate 45E is supported on an output shaft 45D of a drive state switching means 45 having a motor M and a speed reducer. As shown in FIG. 6, two pins 45 </ b> C are erected on the plate 45 </ b> E at a predetermined distance from the output shaft 45 </ b> D in the front-rear direction. The rear ends of the inner cables 80B provided in the outer cable 80A of the connecting means 80 are connected to the two pins 45C. The output shaft 45D extends from the drive state switching means 45 toward the right side, and the plate 45E, the inner cable 80B, and the like are provided above the reservoir tank 92. Thereby, the space above the reservoir tank 92 can be effectively utilized.

Next, the connection of the tension rollers 26 and 36 for connecting and shutting off the transmission of the rotational power by changing the tension of the connecting means 80 and the belts 122 and 132 will be described.
As shown in FIGS. 7 and 8, the front end portion of the outer cable 80 </ b> A of the one side connecting means 80 is supported by a stay 81 provided on the rear upper portion of a rear arm portion 142 of a bracket 140 described later. In addition, the rotary shaft 24 is provided outside the outer periphery of the radiator fan 24 and the dust exhaust fan 30 when viewed in the axial direction. Thereby, the connection means 80 and the stay 81 do not become an obstacle to the ventilation of the radiator fan 20 and the dust exhaust fan 30 and can improve the ventilation efficiency of the radiator fan 20 and the dust exhaust fan 30.

  The front end portion of the inner cable 80B of the connecting means 80 is connected to a belt stopper 26C of a tension roller 26 that connects and shuts off transmission of rotational power by changing the tension of the belt 122 wound around the pulley 23 and the pulley 121. It is connected via an elastic member 82. Thereby, the frequency | count that an excessive load is added to the drive state switching means 45 can be decreased, and the durability of the drive state switching means 45 can be improved.

  The belt stopper 26C is formed in a substantially square shape when viewed in the axial direction of the rotary shaft 24, and includes a belt contact portion on the front end side that contacts the belt 122 and a connection portion that is fixed to the tension arm 26B. Yes. In addition, a front end portion of the inner cable 80B is connected to an intermediate portion of the connection portion via an elastic member 82.

  The tension roller 26 includes a tension arm 26B that is rotatably attached to a support shaft 86 provided in the left and right direction at a rear lower portion of a rear arm portion 142 of a bracket 140, which will be described later, and a tension arm 26B that is rotatable at a tip end portion of the tension arm 26B. The roller 26A is supported, and a belt stopper 26C fixed to the base of the tension arm 26B is provided. The support shaft 86 is provided outside the outer periphery of the radiator fan 24 and the dust exhaust fan 30. Thereby, the support shaft 86 does not become an obstacle to the ventilation of the radiator fan 20 and the dust exhaust fan 30, and the ventilation efficiency of the radiator fan 20 and the dust exhaust fan 30 can be improved.

The tension arm 26 </ b> B of the tension roller 26 and the lower portion of the stay 81 are connected by a spring 85 that urges the tension roller 26 toward the belt 122.
Similarly, as shown in FIGS. 7 and 8, the front end portion of the outer cable 80A of the connecting means 80 on the other side is supported by a stay 81 provided on the rear upper portion of a rear arm portion 142 of a bracket 140 described later, The stay 81 is provided outside the outer periphery of the radiator fan 24 and the dust exhaust fan 30 when viewed in the axial direction of the rotating shaft 24.

  The front end portion of the inner cable 80B of the linking means 80 changes the tension of the belt 33 wound around the pulley 33 and the pulley 131, and connects or disconnects the transmission of the rotational power to the belt stopper 36C of the tension roller 36, such as a spring. It is connected via an elastic member 82. The stay 81 is provided outside the outer periphery of the radiator fan 24 in the axial direction of the rotating shaft 24. The belt stopper 36C is formed in a substantially square shape when viewed in the axial direction of the rotary shaft 24, and includes a belt contact portion on the front end side that contacts the belt 132 and a connection portion fixed to the tension arm 36B. Yes. In addition, a front end portion of the inner cable 80B is connected to an intermediate portion of the connection portion via an elastic member 82.

  The tension roller 36 includes a tension arm 36B that is rotatably attached to a support shaft 86 that is provided in a left-right direction at a rear lower portion of a rear arm portion 142 of a bracket 140, which will be described later, and a tension arm 36B that is rotatable at a tip end portion of the tension arm 36B. The roller 36A is supported, and a belt stopper 36C fixed to the base of the tension arm 26B is provided.

The tension arm 36 </ b> B of the tension roller 36 and the lower portion of the stay 81 are connected by a spring 85 that urges the tension roller 36 toward the belt 132.
FIG. 8 illustrates a state of the tension rollers 26 and 36 in which the radiator fan 20 is in a driving state and the dust exhaust fan 30 is in a stopped state.

  As shown in FIG. 8, when the plate 45E is rotated by the driving state switching means 45 and the inner cable 80B of the connecting means 80 is pulled in and the belt stopper 26C of the tension roller 26 rotates clockwise, the tension roller 26 The roller 26 </ b> A presses the belt 122, and the belt stopper 26 </ b> C of the tension roller 26 is separated from the belt 122 to be in a non-braking state, and transmits the rotational power of the engine E transmitted to the pulley 121 to the pulley 23. That is, the belt 122 and the tension roller 26 constitute a cooling clutch C1, and the cooling clutch C1 is connected by the pressure of the tension roller 26 against the belt 122, and the driving force from the engine E is transmitted to the radiator fan (cooling fan) 20. The

  On the other hand, when the plate 45E is rotated by the drive state switching means 45 to push the inner cable 80B of the connecting means 80 and the belt stopper 36C of the tension roller 36 rotates counterclockwise, the roller 36A of the tension roller 36 is The belt stopper 36 </ b> C of the tension roller 36 is separated from the belt 132 and presses the belt 132 to be in a braking state, thereby quickly interrupting transmission of the rotational power of the engine E transmitted to the pulley 131 to the pulley 23. As a result, in FIG. 8, the rotation of the dust exhaust fan 30 can be quickly stopped, and the air blown by the radiator fan 20 can be prevented from being hindered. That is, the belt 132 and the tension roller 36 constitute a dust removal clutch C 2, and the dust clutch C 2 is connected by the pressure of the tension roller 36 against the belt 132, and the driving force from the engine E is transmitted to the dust removal fan 30. .

  Further, by stopping the operation state of the drive state switching means 45 in the intermediate state, both the cooling clutch C1 and the dust removal clutch C2 can be maintained in a disconnected state. That is, the operating state of the drive state switching means 45 is controlled by the motor M by controlling the operation of the motor M, the cooling state in which the cooling clutch C1 is connected and the dust clutch C2 is shut off, and the cooling clutch C1 is shut off and the dust clutch C2 is turned off. It is switched between a dusting state to be connected and a temperature rising state in which both the cooling clutch C1 and the dusting clutch C2 are shut off.

  The driving state switching means 45 is automatically driven by a control device (not shown) in accordance with the state of the cooling water of the radiator 50 and the like. A switching lever can also be provided in the cockpit 6 or in the space S of the engine room 8 and the front wall 5A of the Glen tank 5 so that the switching can be manually operated.

Next, the rotating shaft 24 to which the radiator fan 20 is attached and the bracket 140 that supports the cylindrical rotating shaft 34 to which the dust exhaust fan is attached will be described.
As shown in FIGS. 7 and 8, the bracket 140 has a rotating shaft 24 fitted in the center portion of the bracket 140 and a support portion 25 that fits the cylindrical rotating shaft 34 is fixed thereto. As shown in FIG. The support part 25 in the bracket 140 is provided at a position biased upward from the center part in the vertical direction of the radiator 50. Thereby, the outside air drawn in by the radiator fan 20 is blown to the upper side of the engine E, and the engine E and the oxidation catalyst device 11 provided on the upper side of the engine E can be efficiently cooled.

  The bracket 140 is formed in a three-pronged shape having three arm portions extending radially in the radial direction around the support portion 25 as viewed in the axial direction of the rotating shaft 24. That is, the bracket 140 extends from the support portion 25 to a substantially upper front side, a rear arm portion 142 extending from the support portion 25 to a substantially rear side, and extends from the support portion 25 to a substantially lower side. The lower arm part 143 to be used is provided.

  The front arm portion 141 is inclined to the right side (outside the fuselage) as it extends to the front end side, and the front end portion is connected to the right front frame 1A. The rear arm part 142 extends in a direction perpendicular to the rotation shaft 24, and the tip part is connected to the right rear frame 1B. The lower arm portion 143 is inclined to the right side (outside the fuselage) as it extends to the distal end side, and the distal end portion is connected to a bracket 1E fixed to the upper side of the fuselage frame 1.

  Thereby, the ventilation efficiency of the radiator fan 20 and the dust exhaust fan 30 can be improved without obstructing the ventilation of the radiator fan 20 and the dust exhaust fan 30. In addition, the rigidity of the bracket 140 is increased, the rotating shaft 24 and the cylindrical rotating shaft 34 can be stably supported, and the radiator fan 20 and the dust exhaust fan 30 can be stably rotated. Furthermore, since the front end portions of the front arm portion 141 and the lower arm portion 143 are inclined toward the right side (outside the fuselage), the spacing portion B can be widely formed on the front side and the lower side of the bracket 140, so that the radiator fan 20, Maintenance / inspection work of the dust exhaust fan 30 and the engine E can be easily performed.

Next, means for changing the mounting position on the rear transmission shaft 110 of the pulley 63 will be described.
As shown in FIG. 9, the pulley 63 to which the rotational power of the engine E is transmitted is fixed to the rear transmission shaft 110 by a key 64. A keyway 111 is formed on the outer peripheral surface of the rear transmission shaft 110. Since the key 64 inserted into the key groove 111 is interposed between the pulley 63 and the rear transmission shaft 110, the pulley 63 is fixed to the rear transmission shaft 110 in a state where relative rotation is impossible. The key grooves 111 are formed at two locations on the outer peripheral surface of the rear transmission shaft 110 with an interval in the axial direction of the rear transmission shaft 110.

  Further, collars 112 and 113 are fitted on the outer peripheral surface of the rear transmission shaft 110. The collars 112 and 113 are members that restrict the pulley 63 from moving in the axial direction of the rear transmission shaft 110. Note that the length of the collar 113 in FIG. 9 in the left-right direction is larger than the length of the collar 112 in the left-right direction.

Thereby, as shown to Fig.9 (a), (b), the attachment position in the axial center direction of the rear part transmission shaft 110 of the pulley 63 can be changed easily.
9A shows a state in which the pulley 63 is attached to the left side in the axial direction of the rear transmission shaft 110, and FIG. 9B shows the right side in the axial direction of the rear transmission shaft 110. The state attached to is shown. When the attachment position of the pulley 63 is changed, the insertion position of the key 64 is changed, and the collars 112 and 113 arranged on the left and right sides of the pulley 63 are exchanged on the left and right sides to be fitted on the rear transmission shaft 110. Further, the position of the tension roller 115A, 115B that presses the pulley 61 and the belt 62 wound around the pulley 63 is changed in accordance with the change of the position of the pulley 63.

  The tension rollers 115A and 115B include a roller 118 and a tension arm 117 that supports the roller 118. In the tension rollers 115A and 115B, a pin 117A provided at the base of the tension arm 117 is rotatably supported on a support portion 116 attached to the body frame 1 by fastening means such as a bolt. A spring (not shown) is connected to the tension arm 117 in order to urge the tension rollers 115A and 115B to the belt 62.

  As shown in FIG. 9A, when the pulley 63 is attached to the left side in the axial direction of the rear transmission shaft 110, the left tension roller 115A provided with the tension arm 117 on the right side of the roller 118 is used. As shown in FIG. 9B, when the pulley 63 is attached to the right side in the axial direction of the rear transmission shaft 110, the right tension roller is provided with a tension arm 117 on the left side of the roller 118. It is preferred to use 115B.

The tension arm 117 of the left tension roller 115A extends in a direction away from the rear transmission shaft 110 while bending in the axial direction of the rear transmission shaft 110. On the other hand, the tension arm 117 of the right tension roller 115B does not bend in the axial direction of the rear transmission shaft 110 but extends away from the rear transmission shaft 110, and a pin 117A provided at the base of the tension arm 117 The left tension roller 115A is longer in the left-right direction than the pin 117A. The right tension roller 115B is preferably provided on the right side of the left tension roller 115A.
(Control circuit)
As shown in FIG. 15, on the input side of the controller CU equipped with a timer circuit, whether the operating state of the drive state switching mechanism 45 is in the above-described cooling state, dust discharge state, or temperature rising state. A switching position detection sensor SS to detect, a water temperature sensor 50T for detecting the temperature of the cooling water of the radiator 50, and an exhaust temperature sensor GP for detecting the temperature of the exhaust gas of the engine E are connected, and the above-mentioned is connected to the output side of the controller CU. A control device U is configured by connecting a relay L1 and a relay L2 for operating the motor M of the operating state switching means 45. The operation state detection sensor SS may be a rotation sensor that detects the number of rotations of the motor M.
(Normal control)
Thus, the timer circuit provided in the controller CU alternately outputs from the controller CU to the relay L1 and the relay L2 at set time intervals. When the motor M is operated, the driving state switching means 45 connects the cooling clutch C1. Interval control is performed in which a cooling state in which the dust clutch C2 is disconnected and a dust state in which the cooling clutch C1 is disconnected and the dust clutch C2 is connected are alternately repeated at predetermined time intervals. Thereby, in the cooling state, the dust exhaust fan 30 is stopped, and the outside air is sucked through the filter body 8B by the rotation of the radiator fan (cooling fan) 20, and passes through the radiator 50 and the engine E. In the dust exhaust state, the radiator fan 20 is stopped, and the dust exhaust blows out from the inside of the radiator 50 toward the outside of the filter body 8B by the rotation of the dust exhaust fan 30, and is adsorbed by the filter body 8B. Dust such as sawdust was blown away. Thereby, the clogging of the filter body 8B is removed, and the intake area of the cooling air is secured.
(Time-related changes in interval control)
In the interval control described above, the length relationship between the connection time of the cooling clutch C1 and the connection time of the dust removal clutch C2 may be changeable.

Accordingly, the rotational time relationship between the cooling fan (20) and the dust exhaust fan (30) in the interval control described above is changed according to the state of dust adhering to the filter body (8B) due to the difference in work conditions, and the engine ( The output of E) can be maintained.
(Time interval setting for reverse operation)
In addition, after the cooling clutch C1 is cut off, a set time (for example, 0.5 seconds) may be set and the dust removal clutch C2 may be connected. As a result, the dust exhaust fan 30 rotates after the rotation due to the inertia of the radiator fan 20 is stopped or decelerated. Therefore, the blowout of the internal air by the dust exhaust fan 30 is less likely to be inhibited by the intake of the outside air due to the rotation of the radiator fan 20. The dust adhering to the filter body 8B can be effectively removed. Further, the load on the power transmission path from the output shaft of the engine E to the radiator fan 20 and the transmission path to the dust exhaust fan 30 is reduced, and durability is improved.
(Changing the time interval of reverse operation)
Further, the set time from when the cooling clutch C1 is disconnected to when the dust clutch C2 is connected may be automatically changed according to the output rotation speed of the engine E. That is, when the output rotation speed of the engine E is lower than the rated rotation speed (for example, 2,800 rotations / minute), the above set time is lengthened, while the output rotation speed of the engine E exceeds the rated rotation speed. If it is high, the set time is shortened. As a result, the stop time of the radiator fan 20 is automatically controlled according to the output state and heat generation state of the engine E, and the reduction in the output of the engine E is reduced to prevent the work efficiency of the work vehicle from being lowered. it can.

  Further, the set time from when the cooling clutch C1 is disconnected to when the dust clutch C2 is connected may be automatically changed according to the temperature of the cooling water of the radiator 50. That is, when the temperature of the cooling water is lower than this with reference to an appropriate range of 85 to 90 degrees Celsius, the above set time is lengthened. On the other hand, when the temperature is higher than this, the above set time is set. To shorten. Thus, when the cooling water temperature is low, the time during which the radiator fan 20 is stopped can be lengthened, the temperature of the cooling water can be raised to an appropriate range, and the output of the engine E can be increased. Further, when the cooling water temperature is high, the time during which the radiator fan 20 is stopped can be shortened to reduce a decrease in output due to overheating of the engine E, thereby preventing a reduction in work efficiency of the work vehicle.

Also, the set time from when the cooling clutch C1 is disconnected until the dust clutch C2 is connected is automatically changed according to the detection result of the exhaust temperature sensor GP that detects the exhaust temperature of the engine E. It may be configured. That is, when the exhaust temperature is lower than the appropriate range, the set time is lengthened. On the other hand, when the exhaust temperature is higher than this range, the set time is shortened. Thereby, when the exhaust temperature is low, the time during which the radiator fan 20 is stopped can be lengthened, the combustion temperature in the cylinder of the engine E can be raised to an appropriate range, and the output of the engine E can be increased. Further, when the exhaust temperature is high, the time during which the radiator fan 20 is stopped can be shortened to reduce the output reduction due to overheating of the engine E, thereby preventing the work efficiency of the work vehicle from being lowered.
(Control by water temperature sensor)
When the engine E is started, if the detection result of the radiator water temperature by the water temperature sensor 50T is lower than a set temperature (for example, 5 degrees Celsius in a cold region), an output is made from the controller CU to the relay L1 / L2, and the driving state is switched. The mechanism 45 is activated. When the switching position detection sensor SS detects that both the cooling clutch C1 and the dust clutch C2 are disconnected, the output from the controller CU to the relay L1 / L2 is stopped, and the drive state switching mechanism 45 is This operating position is maintained.

  As a result, the rotation of the radiator fan 20 and the dust exhaust fan 30 is stopped, and the intake of the cooling air by the radiator fan 20 and the blowing of the dust exhaust air by the dust exhaust fan 30 are stopped. For this reason, the atmosphere does not flow around the engine E and the radiator 50, and the engine E and radiator water temperatures are increased by continuing the driving of the engine E, the combustion efficiency in the cylinder of the engine E is increased, and the engine output is improved.

  When it is detected that the coolant temperature detected by the water temperature sensor 50T has risen to a temperature equal to or higher than the set temperature, an output is made from the controller CU to the relays L1 / L2, and the drive state switching mechanism 45 is activated. When the switching position detection sensor SS detects that the cooling clutch C1 is connected, the output from the controller CU to the relays L1 / L2 stops, and the drive state switching mechanism 45 maintains this operating position.

As a result, the radiator fan 20 rotates and the radiator 50 and the engine E are cooled by the intake of the cooling air, so that a decrease in output due to overheating of the engine E is prevented.
(Control by exhaust temperature sensor)
When the engine E is started, if the detection result of the exhaust temperature by the exhaust temperature sensor GP is lower than the set temperature, an output is made from the controller CU to the relays L1 / L2, and the drive state switching mechanism 45 is activated. When the switching position detection sensor SS detects that both the cooling clutch C1 and the dust clutch C2 are disconnected, the output from the controller CU to the relay L1 / L2 is stopped, and the drive state switching mechanism 45 is This operating position is maintained.

  As a result, the rotation of the radiator fan 20 and the dust exhaust fan 30 is stopped, and the intake of the cooling air by the radiator fan 20 and the blowing of the dust exhaust air by the dust exhaust fan 30 are stopped. For this reason, the atmosphere does not flow around the engine E and the radiator 50, and the combustion temperature in the cylinder of the engine E rises due to the continued driving of the engine E, the combustion efficiency increases, and the engine output improves.

  When it is detected that the exhaust temperature detected by the exhaust temperature sensor GP has risen to a temperature equal to or higher than the set temperature, an output is made from the controller CU to the relays L1 / L2, and the drive state switching mechanism 45 is activated. When the switching position detection sensor SS detects that the cooling clutch C1 is connected, the output from the controller CU to the relays L1 / L2 stops, and the drive state switching mechanism 45 maintains this operating position.

As a result, the radiator fan 20 rotates and the radiator 50 and the engine E are cooled by the intake of the cooling air, so that a decrease in output due to overheating of the engine E is prevented.
(Other control)
In the interval control in which the radiator fan 20 and the dust exhaust fan 30 are alternately driven at a predetermined time interval as described above, during the grain discharging operation by the discharge cylinder 7, the driving time of the dust exhaust fan 30 is It may be set to be longer than the driving time. Thereby, it becomes difficult for the dust generated during the grain discharging operation to be adsorbed to the filter body 8B.

  Moreover, you may comprise so that the cooling clutch C1 and the dust removal clutch C2 may be connected simultaneously. As a result, the radiator fan 20 and the dust exhaust fan 30 rotate together, and the intake of the cooling air by the radiator fan 20 is inhibited, and the warm-up operation of the engine E is promoted.

  Moreover, you may comprise so that the setting time (cycle) by which the cooling clutch C1 and the dust removal clutch C2 are driven alternately may be changed automatically according to the quantity of the harvested cereal. Thereby, when there is much quantity of a harvested cereal grain, the overheating of the engine E by the threshing load can be prevented by lengthening the direction of the connection time of the cooling clutch C1.

  Further, the set time (cycle) in which the cooling clutch C1 and the dust clutch C2 are driven alternately is configured to be automatically changed according to the layer thickness of the processed material on the sorting shelf of the threshing device 3. Also good. Thereby, when there is much quantity of a processed material, the overheating of the engine E by the threshing and selection load can be prevented by lengthening the connection time of the cooling clutch C1.

  Moreover, you may comprise so that the setting time (cycle) by which the cooling clutch C1 and the dust clutch C2 are driven alternately may be changed automatically according to the amount of the waste after threshing. Thereby, when there is much quantity of waste, overheating of the engine E by the threshing load can be prevented by lengthening the connection time of the cooling clutch C1.

  Further, the set time (cycle) in which the cooling clutch C1 and the dust clutch C2 are alternately driven may be automatically changed by switching between the straight traveling state and the turning state. Thereby, in the turning state, the overheating of the engine E due to the turning load can be prevented by extending the connection time of the cooling clutch C1. Conversely, the connection time of the cooling clutch C1 is made longer in the straight traveling state, and the connection time of the dust clutch C2 is made longer in the turning state, so that the filter 8B is adsorbed in the turning state with less dust. The blown dust can be blown away at once.

  Further, it may be set such that the connection time of the cooling clutch C1 is longer during the cutting travel, and the connection time of the dust clutch C2 is longer during the non-cutting travel such as on the road. Thereby, the overheating of the engine E due to the load of the cutting operation can be prevented.

  Further, in a high load state where the rotation speed of the engine E decreases, the connection time of the cooling clutch C1 becomes longer, and in a low load state where the rotation speed of the engine E increases, the connection time of the dust clutch C2 becomes longer. You may set so that it may become long. Thereby, the overheating of the engine E due to the load of the cutting operation can be prevented.

8B Filter body 20 Radiator fan (cooling fan)
30 Dust exhaust fan 45 Driving state switching means 50 Radiator 50T Water temperature sensor C1 Cooling clutch C2 Dust clutch E Engine GP Exhaust temperature sensor U Controller

Claims (8)

  A radiator (50) is disposed outside the engine (E), and a filter body (8B) for filtering dust is disposed outside the radiator (50). Between the engine (E) and the radiator (50), The cooling fan (20) and the dust exhaust fan (30), whose blade angles are opposite to each other, are rotatably provided on the same axis, and the driving force is transmitted from the engine (E) to the cooling fan (20). A cooling clutch (C1) that connects and disconnects the engine, and a dust removal clutch (C2) that connects and disconnects transmission of driving force from the engine (E) to the dust exhaust fan (30). Drive state switching means (45) that is interval-controlled so as to alternately connect the dust clutch (C2) at predetermined time intervals is provided, and when the engine (E) is started, the dust clutch (C2) is connected. The in Driving portion of the structure and the working vehicle Baru control is started.   The driving | running | working part of the working vehicle of Claim 1 made it the structure which can change the connection time relationship of the cooling clutch (C1) and dust removal clutch (C2) in the said interval control.   Switchable between a state in which the cooling clutch (C1) and the dust clutch (C2) are alternately connected at a predetermined time interval and a state in which both the cooling fan (C1) and the dust clutch (C2) are shut off The driving | running | working part of the working vehicle of Claim 1 comprised as a structure.   A water temperature sensor (50T) that detects the temperature of the cooling water of the radiator (50) is provided, and when the cooling water temperature detected by the water temperature sensor (50T) is lower than a set temperature, the cooling clutch (C1) The driving | running | working part of the working vehicle of Claim 3 provided with the control apparatus (U) which interrupts | blocks both dust clutches (C2) automatically.   The cooling clutch (C1) is configured to be automatically connected when it is detected that the cooling water temperature detected by the water temperature sensor (50T) has risen to a temperature equal to or higher than a set temperature. The driving part of the working vehicle.   An exhaust temperature sensor (GP) for detecting the temperature of the exhaust gas of the engine (E) is provided, and when the exhaust temperature detected by the exhaust temperature sensor (GP) is lower than a set temperature, the cooling clutch (C1) 4. The driving part of the working vehicle according to claim 3, further comprising a control device (U) that automatically shuts off both the exhaust gas clutch and the dust clutch (C <b> 2).   When the exhaust temperature sensor (GP) provided in the exhaust path of the engine (E) detects that the exhaust temperature has risen above the set exhaust temperature, the cooling clutch (C1) is automatically connected. The driving | running | working part of the working vehicle of Claim 6 set as the structure comprised.   When the cooling clutch (C1) and the dust clutch (C2) are alternately connected at a predetermined time interval, the dust clutch (C2) is left after a predetermined time after the cooling clutch (C1) is disconnected. The driving | running | working part of the working vehicle of Claim 1 made into the structure to which these are connected.

Images