JP2000229521A - Cooling mechanism of working vehicle equipped with vertical engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent noise from an engine from reaching an operator in a driver's seat in a working vehicle equipped with a vertical type engine. SOLUTION: An intake and exhaust duct is provided in an engine room housing an engine 8, an intake 9a of the intake duct and an exhaust port 46 of the exhaust duct are provided in separated positions on an opposite side from a driver's seat, and an intake side end of an intake pipe 27 of an air cleaner is arranged inside the duct. The duct is divided into an engine side duct attached to the engine 8 and a bonnet side duct 33 attached to a bonnet 9. A filter 35 inclined in regard to a transverse section of the duct is arranged inside the bonnet side duct 33.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for cooling a vertical engine mounted on a riding work machine.

[0002]

2. Description of the Related Art A traveling vehicle equipped with a vertical engine is well known.
Like No. 9. That is, as shown in FIG. 9, a vertical engine 8 'is mounted at a position in front of a driver's seat 7' of a traveling vehicle body (or rearward when the seat direction is opposite), and an output shaft 8'a is connected to a pair of right and left. A traveling device drive pulley 12 'and a work implement output pulley are fixedly protruded downward from between the main frames 2'. A driving force is transmitted from the traveling device drive pulley to the traveling device via a belt. Further, a work implement output pulley is fixed to the output shaft so that a work implement such as a mower 17 'or a tilling device can be driven. Further, a cooling fan 21 'is pivotally supported above the engine, and a radiator 22' which is integrally supported with the engine is disposed above the cooling fan 21 '. The radiator 22' Had to be cooled. Further, the radiator cooling water is circulated between the engine and the engine.

[0003]

In order to cool the above-mentioned conventional vertical engine 8 ', the outside air is sucked from a bonnet 9' above the vertical engine 8 '. There is no need to provide an introduction path, and a battery or fuel tank can be disposed in the space in front of the introduction path so that it can be used effectively. However, the cooling air intake 9a 'provided in the bonnet is located near the driver's seat 7'. As a result, the noise of the engine was transmitted to the operator seated in the driver's seat, which significantly deteriorated the working environment. In addition, when the hood is downsized, the arrangement of the air cleaner and the arrangement of the intake pipe of the air cleaner are restricted, and it is difficult to take in low-temperature air with less dust and dirt. In addition, the radiator filter is disposed inside the cooling air inlet above the bonnet 9 ', so that the inside cannot be directly seen from outside the machine, resulting in poor maintenance. Further, the exhaust air that has cooled the engine and the like is directly discharged downward, and for example, a mower 1
When 7 'is arranged, there is a problem that the cut grass is diffused, and the engine noise also leaks outside from below.

[0004]

The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described. That is, in a working vehicle equipped with a vertical engine, a suction duct and an exhaust duct are provided in an engine room that houses the engine, and an intake of the intake duct and an exhaust of the exhaust duct are provided.
It is provided at a position remote from the driver's seat. Further, in a working vehicle equipped with a vertical engine, an engine-side duct for guiding cooling air is provided above the engine, and an intake-side end of an intake pipe of an air cleaner is arranged in the duct. Further, in a working vehicle equipped with a vertical engine, a duct for sucking the cooling air of the engine is provided in a hood, and an engine-side duct having the duct attached to the engine and a hood-side duct attached to the bonnet. And a filter that is inclined with respect to the duct cross section is disposed in the hood-side duct. Further, in a working vehicle equipped with a vertical engine and covering the engine with a bonnet, the engine is mounted and fixed on a mounting plate, an exhaust port is provided on one side of the mounting plate, and the other surroundings and the engine are mounted. A seal is provided between the cooling plate and a member that covers the cooling duct. In addition, a vertical engine is mounted, the upper part of the engine is covered with a bonnet, the engine is mounted on a mounting plate, the lower part of the engine is mounted, and an HST type stepless is mounted below the mounting plate. A work vehicle in which a transmission is arranged, wherein an introduction port is opened in a mounting plate above the HST-type continuously variable transmission, and a shroud that covers the outside of a cooling fan of the HST-type continuously variable transmission below the introduction port. Is provided. In addition, a vertical engine is mounted, the upper part of the engine is covered with a bonnet, the engine is mounted on a mounting plate, the lower part of the engine is mounted, and an exhaust port is provided on one side of the mounting plate. A muffler is disposed at an end of the exhaust port, and an exhaust communication pipe communicating between the muffler and the engine is fixed to a mounting plate.

[0005]

Next, embodiments of the present invention will be described. FIG. 1 is an overall side view of a traveling work vehicle equipped with a vertical engine at a rear portion, FIG. 2 is a side cross-sectional view illustrating a configuration for introducing cooling air into a hood housing a vertical engine,
FIG. 3 is a plan view partially broken away, FIG. 4 is a rear sectional view of the same, FIG. 5 is a plan view of an anti-vibration support structure of the engine, FIG. 6 is a plan view of an anti-vibration support member, FIG. FIG. 8 is a side cross-sectional view of the same, and FIG. 9 is a side cross-sectional view of a cooling configuration in a hood housing a conventional vertical engine.

First, a working vehicle 1 equipped with a vertical engine 8 will be described with reference to FIG. Front frame 2
and a main frame 2 comprising a rear frame 2b, a front wheel 3 is suspended from the front frame 2a, a rear wheel 4 is suspended from the rear frame 2b, and the front frame 2a and the rear frame 2 are suspended.
b is pivotally supported so as to be able to turn left and right. The front frame 2a
A front column 5 is set up on the front column, and a front wheel 3 can be steered by a steering handle 6 provided on the front column 5. A driver's seat 7 is mounted on a front frame 2 a behind the front column 5. ing. Then, the vertical engine 8 is mounted on the rear frame 2 via a vibration isolating support member 11 described later.
Of the engine 8 is covered with a rear cover 10, and a bonnet 9 is mounted on the rear cover 10.
Is mounted, and a lower rear portion of the hood 9 is a rear cover 10.
Pivotally supported on the rear of the vehicle so as to be pivotable rearward and upward.

As shown in FIGS. 1 and 2, the engine 8 is of a vertical type, and its output shaft 8a is provided between the rear frames 2 and 2 arranged in parallel in the left-right and front-rear directions. The traveling device driving pulley 1 is provided on the output shaft 8a.
2 and a work implement pulley 13 are fixedly connected, and the motive power is transmitted from the traveling device drive pulley 12 to a HST type continuously variable transmission 14 interposed between the rear wheels 4 and 4 below the engine 8 via a belt 15 through a belt, The rear wheels 4 can be driven via an axle projecting left and right from the HST-type continuously variable transmission 14.
A mowing operation is performed by transmitting a driving force to the work machine pulley 13 via a belt 16 to a mower 17 suspended below the front of the work vehicle 1.

Next, as shown in FIG. 5, the structure for mounting and supporting the engine 8 is such that the rear frames 2a are connected by connecting frames 2c and 2d, and the connecting frames 2c and 2d are connected.
The anti-vibration support members 11, 11, 11, 11 are mounted thereon, and an engine mounting plate 20 having a quadrangular shape in a plan view is screwed onto the anti-vibration support members 11, 11, 11, 11.
The mounting plate 20 is formed in a concave shape when viewed from the side. The engine 8 is mounted on the mounting plate 20 in the recessed portion, and the anti-vibration support members 11, 11, 11, 11 are disposed at the four corners to prevent the mounting. I am trying to support it. Further, as shown in FIG. 2, a seal member 32 made of sponge, rubber, synthetic resin, or the like is interposed between the front outer edge of the mounting plate 20 and the front lower inner edge of the rear cover 10. Has been preventing leakage from between. A seal member 32 similar to the above is disposed between the mounting plate 20 and the rear frame 2a or between the mounting plate 20 and the rear cover 20 to prevent leakage. In this way, the mounting plate 20, the rear cover 10, and the hood 9 cover the periphery of the engine 8 and also serve as a sound insulating member, so that there is no need to provide a special sound insulating member, thereby reducing costs.

A substantially circular air outlet 20a is opened at the rear of the mounting plate 20, and the air outlet 46 is provided at a fixed interval between the rear end of the mounting plate 20 and the rear of the rear cover 10. Is formed in the exhaust port 46, and an opening for exhausting the exhaust air, which will be described later, communicates from the engine room to the outside. A silencer 24 is arranged at a lower rear portion of the rear cover 10 which is a lower portion of the opening,
The silencer 24 is fixed via a stay 25 projecting rearward and downward from the left and right center of the rear end of the mounting plate 20, and exhaust gas is exhausted from a position farthest from the driver's seat 7 behind the cooling exhaust port 46. , The sound is muted.

As shown in FIGS. 6 to 8, the vibration isolating support member 11 includes a lower fixing portion 50 and an upper fixing portion 51, each of which has a vibration isolating rubber 5.
2, and the lower fixing portion 50 is formed in a U-shape in cross section, and the bottom portion serving as a closed surface is fixed on the frame 2c or 2d using bolts. Then, the outer peripheral surface of the cylindrical body 53 is fixed or placed in the open surface above the lower fixing part 50, and the cylindrical body 53 is formed into a cylindrical shape with the axial center thereof oriented horizontally. A connection shaft 54 is fitted through the center of the rubber 52.

The upper fixing portion 51 is formed in a U-shape with its lower part opened in a side view, and the lower part of the upper fixing part 51 is provided with a connecting shaft 54 and a protective member in the open surface of the upper fixing part 51. The upper fixing part 51 is connected to the lower fixing part 50 through the vibration-proof rubber 52 by disposing the both ends of the vibration-proof rubber 52 so as to sandwich the same and fitting the connecting shaft 54 into the inner peripheral surface of the vibration-proof rubber 52. Let me.
The upper portion of the upper fixing portion 51 is formed in a rectangular shape in plan view,
A square opening is provided in the center, and screw shafts 55 are projected upward on both sides of the upper fixing portion 51 so that the mounting plate 2
0 can be screwed.

The anti-vibration support member 11 is compared with the elastic constant a in the axial direction of the cylindrical anti-vibration rubber 52.
The elastic constant b in the direction orthogonal to the axis of the shaft is increased.

The anti-vibration support members 11 ・ 11 ・ 11 ・ 11
Are the main frame 2 and the frame 2 as shown in FIG.
c · 2d are arranged in front, rear, left and right, respectively, and a substantially corner portion of a mounting plate 20 having a quadrangular shape in a plan view is mounted thereon, thereby forming an engine mount. Further, the anti-vibration support member 11
The direction perpendicular to the axis having a large elastic constant of 11 ・ 11 ・ 11 is substantially matched with the radial direction of the output shaft 8a.
Therefore, vibrations of the engine 8 in the front-rear and left-right directions are absorbed, and the space between the mounting plate 20 and the rear frame 2b and the rear cover 10 is sealed by the seal member 32, so that noise is leaked even if there is vibration. It is preventing. In addition, the cooling air of the engine 8 is guided by the mounting plate 20 to the exhaust air introduction port 20a and the exhaust port 46. The mounting plate 20 also serves as a part of a cooling duct, an engine mount, and a soundproof material. It has a configuration.

A cooling fan 21 is fixed to the upper end of the crankshaft of the engine 8, a radiator 22 is arranged above the cooling fan 21, an air cleaner 26 is arranged behind the engine 8, and further behind it. The fuel tank 23 is disposed at the center.

As shown in FIGS. 2 to 4, an outer peripheral portion of the cooling fan 21 above the engine 8 is covered by a shroud 29, and the radiator 22 is covered by an engine side duct 30 and the bonnet 9. By opening the filter, the filter arranged on the upper surface of the radiator 22 can be visually checked, and maintenance such as replacement can be easily performed. The engine-side duct 30 is fixed to the engine 8 side, and separates the cooling fan 21 and the radiator 22 from a horizontal plate 30a, and a left and right side portion and a rear portion of the horizontal plate 30a, which are bent upward to rise upward.
0b and 30b and a rear plate 30c, the outer peripheral end of which is formed into an arc shape substantially conforming to the inner shape of the bonnet 9, and a sealing member made of sponge, rubber, synthetic resin, or the like between the outer peripheral end surface and the bonnet 9 31 is interposed to prevent leakage.

A radiator 2 is provided on the horizontal plate 30a.
A communication opening 30d having a rectangular shape in a plan view is opened substantially in conformity with the shape of FIG. 2, and cooling air is sent to the engine 8 by the cooling fan 21. Duct entrance 3 with large width
0e is opened, and an insertion hole 30f is opened on the other side (right side).

A hood-side duct 33 communicates with the duct inlet 30e. The hood-side duct 33 is formed in a substantially inverted L-shape in a side view so as to extend along the rear upper portion and the rear surface of the bonnet 9. It is formed so as to cover the fuel tank 23 and the like, and is fixed to the inner surface of the hood 9. The left and right width of the hood side duct 33 is approximately the radiator 2
2 to secure a large flow path, and the front end of the hood-side duct 33 is shaped to match the width of the duct entrance 30e. An intake pipe 27 is inserted into the insertion hole 30f, and an intake side end of the intake pipe 27 is positioned to face the engine side duct 30 so that cooling air can be sucked. Is connected to an air cleaner 26 disposed at the rear of the engine 8.

The rear portion of the hood-side duct 33 extends to the lower rear portion of the hood 9 and is closed, and the bulging portion 1 bulges above the rear portion of the rear cover 10.
0a is interposed with a seal member. Cooling air inlets 9a, 9a, 9a are opened on the rear surface of the bonnet 9 to take in cooling air from a position further away from the operator, and the cooling air inlets 9a, 9a.
The opening 9a is long at the left and right, and is arranged at a certain interval in the vertical direction to increase the opening area so as to easily take in outside air.

When the cooling fan 21 is driven in this way, outside air is taken into the hood-side duct 33 from the cooling air inlets 9a, 9a, 9a, and
And flows downward through the radiator 22 to cool the engine 8, flow rearward along the mounting plate 20 constituting the engine mount, and exhaust through an opening in the rear of the engine room behind the mounting plate 20. Like that.

Therefore, the cooling air inlets 9a, 9a, 9
a is not above the engine 8 as in the prior art,
Since it is opened at a position further distant from the rear and the other opening is only the exhaust port 46 below it, leakage of engine sound and the like is prevented by the cooling air intake ports 9a, 9a, 9a and the exhaust port The noise leaks to the outside, and the noise on the operator on the driver's seat 7 is considerably reduced.

Further, since the engine-side duct 30 constituting the cooling passage is fixed to the engine 8 and separate from the bonnet-side duct 33 fixed to the bonnet 9, the bonnet 9 is located at the lower rear. When the engine side duct 30 is turned around the turning fulcrum 41 of the
You can eliminate complicated work such as removing more,
Further, maintenance of the engine 4, the air cleaner 26, and the like can be easily performed.

The air taken into the hood 9 is cleaned. That is, the cooling air intake 9
The a, 9a and 9a are covered with a first filter 34 having a coarse mesh so as to prevent large dusts such as cut grass from entering the hood side duct 33. further,
The hood-side duct 33 formed in a substantially inverted L-shape when viewed from the side.
A second filter 35 having a fine mesh is interposed in a middle portion (a bent portion in the present embodiment) of the above. The second filter 35 is mounted so as to rise rearward and inclined so that dust and the like fall down due to the vibration of the engine 8 and the like, fall down to the lower rear portion of the hood-side duct 33 and accumulate, and the hood 9 is easily opened. It can be cleaned. Further, by making the cross section of the second filter 35 inclined with respect to the cross section of the hood side duct 33, the area of the second filter 35 becomes larger than the cross section area of the hood side duct 33.
Dust and the like in the outside air flowing inside are surely removed.

The outside air purified in two stages by the first filter 34 and the second filter 35 is sent from the front end of the hood-side duct 33 into the engine-side duct 30 through the duct inlet 30e, and is disposed on the upper surface of the radiator 22. This prevents dust and the like from adhering to the clogged net and causing clogging. In addition, the air after cleaning in two stages is present in the engine-side duct 30 as described above, and this air is taken into the air cleaner 26 through the intake pipe 27, so that the load on the air cleaner 26 can be reduced. Therefore, the life can be prolonged, and the outside air having a low temperature is sucked, so that the combustion efficiency is improved.

As shown in FIG. 2, the rear part of the mounting plate 20 and the rear cover 1 constituting the engine mount are described.
0, a plurality of cooling air outlets 45
A plate 45 having openings a, 45a,... is arranged to limit the amount of exhaust air discharged outside the engine room.

As shown in FIGS. 2 and 5, the HST-type continuously variable transmission 14 is provided below the rear portion of the mounting plate 20.
A hydraulic pump 14a is disposed, an exhaust air introduction port 20a is opened in the mounting plate 20 at the upper position, and an input pulley 44 is provided on an input shaft 14b of the hydraulic pump 14a projecting upward. A fan 42 is fixed on the upper part, and a cylindrical shroud 43 is further provided on an outer peripheral portion of the fan 42. The shroud 43 has a substantially cylindrical shape that matches the shape of the exhaust air introduction port 20a. The exhaust air is exhausted downward to cool the hydraulic pump 14a. The shroud 43 prevents noise from spreading in all directions.

A cutout portion 20b is provided at a part of the outer peripheral portion of the exhaust air introduction port 20a. The cutout portion 20b passes through the exhaust communication pipe 40 and is connected to the muffler 24. Have been. The exhaust communication pipe 40 is fixed to the mounting plate 20 and is arranged in a flow path of the exhaust air.

Therefore, the exhaust air sent downward by the cooling fan 21 to cool the engine 8 flows rearward along the mounting plate 20 where the opening of the engine room is provided, and The exhaust communication pipe 40 is cooled, and a part of the exhaust air is cooled by the cooling exhaust ports 45a and 45.
a, the muffler 24 provided in the exhaust port 46 is cooled and discharged to the outside of the engine room.

The remaining cooling exhaust air is supplied to a fan 42.
Is driven through the exhaust air inlet 20a, and the HST
The HST type continuously variable transmission 14 is cooled down by flowing downward along the outer periphery of the hydraulic pump 14a, thereby suppressing a rise in oil temperature in the HST type continuously variable transmission 14 so that a stable traveling driving force can be obtained. .

The cooling exhaust vents 45a, 45a,.
By replacing the opening with a larger opening area, the amount of exhaust air flowing to the muffler 24 side can be increased, and the cooling efficiency of the muffler 24 can be increased.
By reducing the opening area of 45a..., The amount of exhaust air exhausted from the exhaust air inlet 20a can be increased, and the cooling efficiency of the HST type continuously variable transmission 14 can be improved.
By providing and changing the plates 45 having different opening areas of the cooling air outlets 45a, the running performance can be adjusted to the region and the use condition.

[0030]

The present invention is configured as described above.
The following effects are obtained. That is, in a working vehicle equipped with a vertical engine, a suction duct and an exhaust duct are provided in an engine room that houses the engine, and an intake of the suction duct and an exhaust duct are provided. By providing the outlet of the wind duct at a position opposite to the driver's seat, as in the conventional configuration, the cooling air intake is provided directly above the engine, and the intake is located in the driver's seat. It became a nearby position, and the noise leaked from the intake and the operating environment of the operator was deteriorated, but since the intake and exhaust of the cooling air were located far from the driver's seat,
The noise from the engine that can be heard by the operator is reduced and reduced, thereby improving the working environment.

According to a second aspect of the present invention, in a working vehicle equipped with a vertical engine, an engine-side duct for guiding cooling air is provided above the engine, and an intake-side end of an intake pipe of an air cleaner is provided in the duct. The air cleaner after removing large dust and dirt is sucked into the duct when sucked into the duct, reducing the burden of clogging, extending the life of the air cleaner, and reducing costs. In addition, the intake noise of the air cleaner can be reduced.

According to a third aspect of the present invention, there is provided a working vehicle equipped with a vertical engine, wherein a duct for sucking cooling air for the engine is provided in the hood, and the duct is attached to the engine. The hood is divided into a side duct and a hood-side duct attached to the bonnet, and a filter that is inclined with respect to the duct cross-section is arranged in the bonnet-side duct. This prevents clogging due to dust or the like adhering to the device.
Also, when the hood is opened, the hood-side duct is lifted together with the hood, and the upper part around the engine can be opened to allow maintenance of the air cleaner and engine oil, etc. The condition of clogging of the filter with dust and the like can be determined from the outside, and the maintainability is improved. Further, the opening and closing structure of the hood can be simplified.

According to a fourth aspect of the present invention, in a work vehicle having a vertical engine mounted thereon and covering the engine with a bonnet, the engine is mounted and fixed on a mounting plate, and one side of the mounting plate. Since the exhaust plate is provided, and the space between the other surroundings and the member covering the engine is sealed, and the mounting plate is made a part of the cooling duct, the sound insulation of the engine room can be improved. The cooling air that has cooled the radiator and the engine can be exhausted to the outside along the mounting plate, so that there is no need to provide a separate exhaust duct, the number of parts can be reduced, and costs can be reduced.

According to a fifth aspect of the present invention, a vertical engine is mounted, an upper portion of the engine is covered with a bonnet, the engine is mounted on a mounting plate, and a lower portion of the engine is mounted. A work vehicle in which an HST-type continuously variable transmission is arranged below the mounting plate, wherein an introduction port is opened in a mounting plate above the HST-type continuously variable transmission, and an HST-type continuously variable transmission is provided below the introduction port. Since the shroud that covers the outside of the cooling fan of the stepped transmission is provided, the cooling air sucked by the cooling fan is adjusted by the shroud to efficiently reduce the H.
It flows to the ST-type continuously variable transmission, and the engine can be cooled at the same time to improve the cooling performance. Further, since the opening is restricted by the shroud, the sound insulation can be improved.

According to a sixth aspect of the present invention, a vertical engine is mounted, an upper portion of the engine is covered with a bonnet, the engine is mounted on a mounting plate, and a lower portion of the engine is mounted. An exhaust port is provided on one side of the mounting plate, a muffler is disposed at an end of the exhaust port, and an exhaust communication pipe communicating between the muffler and the engine is fixed to the mounting plate. Accordingly, the exhaust communication pipe can be cooled, the utilization rate of the exhaust air can be increased, and it is not necessary to separately provide a fixing member for the exhaust communication pipe, and cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an overall side view of a traveling work vehicle equipped with a vertical engine at a rear portion.

FIG. 2 is a side cross-sectional view showing a configuration for introducing cooling air into a hood housing a vertical engine.

FIG. 3 is a partially cutaway plan view of the same.

FIG. 4 is a rear sectional view of the same.

FIG. 5 is a plan view of an anti-vibration support structure of the engine.

FIG. 6 is a plan view of an anti-vibration support member.

FIG. 7 is a front view of the same.

FIG. 8 is a side sectional view of the same.

FIG. 9 is a side cross-sectional view of a cooling configuration in a hood housing a conventional vertical engine.

[Explanation of symbols]

 7 Driver's Seat 8 Vertical Engine 9 Bonnet 9a Cooling Air Inlet 14 HST Type Continuously Variable Transmission 14b Input Shaft 20 Mounting Plate 20a Exhaust Air Inlet 21 Cooling Fan 22 Radiator 26 Air Cleaner 27 Intake Pipe 30 Engine Side Duct Forming Part 33 Bonnet side duct 34 First filter 35 Second filter 40 Exhaust connection pipe 42 Fan 43 Shroud 72 Engine

Claims (6)

[Claims] In a work vehicle equipped with a vertical engine, a suction duct and an exhaust duct are provided in an engine room accommodating the engine, and an intake of the intake duct and an exhaust duct of the exhaust duct are provided. A cooling mechanism for a working vehicle equipped with a vertical engine, wherein the exit is provided at a position opposite to the driver's seat. 2. A work vehicle equipped with a vertical engine, wherein an engine-side duct for guiding cooling air is provided above the engine, and a suction-side end of an intake pipe of an air cleaner is arranged in the duct. Cooling mechanism for work vehicles equipped with vertical engines. 3. A work vehicle equipped with a vertical engine, wherein a duct for sucking cooling air from the engine is provided in a bonnet, and the duct is attached to an engine-side duct attached to the engine and to the bonnet. A cooling mechanism for a working vehicle equipped with a vertical engine, wherein the cooling mechanism is divided into a hood-side duct and a filter that is inclined with respect to a cross section of the duct is disposed in the hood-side duct. 4. A work vehicle having a vertical engine mounted thereon and covering the engine with a bonnet, wherein the engine is mounted and fixed on a mounting plate, and an exhaust port is provided on one side of the mounting plate. A cooling mechanism for a working vehicle equipped with a vertical engine, wherein a seal is provided between the surroundings and a member covering the engine, and the mounting plate is a part of a cooling duct. 5. A vertical engine is mounted, an upper part of the engine is covered with a bonnet, the engine is mounted on a mounting plate, a lower part of the engine is mounted, and an HST is mounted below the mounting plate. A work vehicle provided with a continuously variable transmission, wherein an introduction port is opened in a mounting plate above the HST continuously variable transmission, and a cooling fan of the HST continuously variable transmission is provided below the introduction port. A cooling mechanism for a working vehicle equipped with a vertical engine, which is provided with a shroud for covering the vehicle. 6. A vertical engine is mounted, an upper portion of the engine is covered with a bonnet, the engine is mounted on a mounting plate, a lower portion of the engine is mounted, and one side of the mounting plate is mounted. Cooling a working vehicle with a vertical engine, wherein an exhaust port is provided, a muffler is disposed at an end of the exhaust port, and an exhaust communication pipe communicating between the muffler and the engine is fixed to a mounting plate. mechanism.