BACKGROUND OF THE INVENTION

The invention according to the present application relates to a working vehicle.

Recently, enactment of strict emission regulation on diesel engines has led to increased demands for installing a post-processing device, such as an exhaust gas purifying device, in a farm work machine, a construction machine, a vessel, and the like including the diesel engine. The post-processing device executes purification processing for air pollutants in exhaust gas. In some conventional working vehicles, such as a tractor, the exhaust gas purifying device is disposed together with the diesel engine in an engine compartment below the hood, to be installed in the vehicle (see Japanese Unexamined Patent Application Publication No. 2013-116692).

In the working vehicle such as a tractor, a pair of fuel tanks, storing fuel supplied to the engine, are respectively disposed on left and right sides of a vehicle body to make space for the engine, a transmission, and the like (see Japanese Unexamined Patent Application Publication No. 2010-042779).

SUMMARY OF THE INVENTION

When the diesel engine provided with the exhaust gas treatment device described above is employed in the working vehicle such as a tractor, not only the diesel engine and the exhaust gas treatment device but also a radiator, a battery, and electronic components for the exhaust gas treatment device need to be crammed in a small and limited installation space.

In the installation space of the working vehicle, when the diesel engine is driven, the diesel engine emits heat, and thus temperature of the diesel engine itself as well as the exhaust gas purifying device becomes extremely high. Thus, the temperature in the engine compartment needs to be adjusted so that adverse effect of the heat emitted from the diesel engine and the exhaust gas treatment device can be prevented. All things considered, appropriate arrangement and cooling structures need to be pursued. Furthermore, heating of a driver's seat, disposed on the rear side of the engine compartment, needs to be reduced or else, comfort of an operator in the cabin is compromised.

When the post-processing device such as the exhaust gas purifying device is installed, a large engine compartment space is required. Thus, a hood becomes large, requiring a highly rigid opening/closing structure. The load is especially concentrated on a fulcrum position when the hood is opened, and thus a highly rigid rotatably supporting mechanism is preferably provided. Furthermore, the inside of the engine compartment is required to be easily accessed for performing a maintenance work and the like.

A technical object of the invention according to the present application is to provide an improved working vehicle in view of the current situation described above.

The invention according to the present application is a working vehicle including: an engine installed in a front portion of a traveling machine body; and a post-processing device configured to purify exhaust gas from the engine. The post-processing device is mounted on an upper side of the engine. The engine and the post-processing device are covered with a hood. A hood shield plate is disposed on a rear surface side of the hood and covers at least the post-processing device from a rear surface. A heat insulating layer is formed between an operating seat disposed on a rear side of the hood and the hood shield plate.

In the working vehicle according to the invention according to the present application, the post-processing device may be disposed in parallel with an output shaft of the engine. The hood shield plate may include: a first shield surface that is disposed on one side of the hood and covers a rear side of the post-processing device; a second shield surface extending forward from a side edge of the first shield surface; and a third shield surface that extends toward another side of the hood from a front edge of the second shield surface. On the rear surface of the hood, an open space may be provided between the third shield surface of the hood shield plate and the other side of the hood, and an exhaust pipe connected to an exhaust side of the post-processing device may extend toward the rear side of the hood.

In the working vehicle according to the invention according to the present application, the hood shield plate may have recesses and protrusions formed at a predetermined interval to block sound generated from an engine compartment below the hood.

In the working vehicle, the hood shield plate covering a rear side of the engine may be fixed to the traveling machine body to be disposed on the rear surface of the hood. A heat shield plate may be disposed between the hood and the post-processing device. The hood may pivot about an upper end position of the hood shield plate to be opened and closed.

In this configuration, the hood shield plate may be disposed while being separated from a front side of the operating seat disposed on the rear side of the hood. Beam frames in parallel with the traveling machine body may be disposed on both sides on a front surface of the hood shield plate. The hood may include: a hinge having a pivoting portion connected to a rear end position of the hood; and a damper that has one end connected to a front side of the hood and makes a telescopic movement. A fixed portion of the hinge may be connected to a hood supporting portion provided on an upper edge side of the hood shield plate. Another end of the damper may be rotatably supported by the beam frame.

In the working vehicle, a radiator for cooling the engine with water and a cooling fan for cooling the engine and the radiator with air are provided. The cooling fan may be disposed on a front surface side of the engine. The radiator may be disposed on a front side of the cooling fan. The post-processing device may be mounted on the upper side of the engine. The radiator, the cooling fan, the engine, and the post-processing device may be covered with the hood. Cooling air may be taken into the hood through a front grille formed on the front surface of the hood, by driving the cooling fan. Openings may be formed in both left and right side portions of the hood. Shielding plates may be disposed at positions close to left and right side portions of the radiator.

In this configuration, the radiator may stand on a front portion of the traveling machine body. A fan shroud surrounding the cooling fan may be attached to a rear surface side of the radiator. When the hood is closed, the shielding plates provided to the hood may be in contact with both left and right side portions of the fan shroud. An opening may be further formed on the ceiling portion of the hood. The fan shroud may have an upper surface provided with an upper shielding portion that extends in a left and right direction and left and right surfaces provided with a pair of left and right side shielding portions extending in an upper and lower direction. When the hood is closed, the upper shielding portion may be disposed close to a back surface of the hood ceiling portion, and the side shielding portions may be in contact with the shielding plates of the hood. The openings on the ceiling portion and the both left and right side portions of the hood may be disposed more on a front side than the fan shroud.

In the working vehicle, engine covers formed of a porous plate may be provided on left and right rear lower sides of the hood. The engine cover may have an upper end position positioned below the post-processing device. Thus, air heated by the engine and the post-processing device may be discharged outside, while achieving a high temperature maintaining effect for the post-processing device with the hood, so that a regeneration operation can be performed under high temperature.

In the embodiment of the invention according to the present application, heat from an engine compartment below the hood is shielded by the hood shield plate. The operating seat can be prevented from being heated by exhaust heat from the engine compartment. Thus, an operator on the operating seat can comfortably operate the vehicle without being affected by exhaust heat from the engine and the post-processing device. The operating seat and the hood are separated from each other. Thus, the hood may have a large outer dimension and can still be sufficiently opened. As described above, even when the engine compartment incorporates a heat emitting member such as the post-processing device, with a large volume achieved in the hood, the hood can be less affected by heat emitted from the post-processing device.

The hood shield plate has first to third shield surfaces bent in a crank shape. Thus, rear and side portions of the post-processing device as the heat emitting member shield are shielded, whereby the operating seat on the rear side of the engine compartment can be less affected by the heat. An open space is provided between the third shield surface that is relatively less affected by heat and the hood. Thus, a tail pipe can be disposed at a position less likely to involve an operation of getting ON/OFF the vehicle by the operator. The third shield surface that is relatively less affected by heat is positioned on the front side. Thus, components such as a hydraulic pump can be disposed in a large space extending toward the operating seat.

The hood shield plate is provided with the recesses and the protrusions. Thus, noise generated from the engine in the engine compartment can be attenuated by the recesses and the protrusions of the hood shield plate so as not to be transmitted to the operating seat.

In the embodiment of the invention according to the present application, the heat shield plate is disposed above the post-processing device, whereby the hood can be prevented from being heated by heat emitted from the post-processing device and the engine. The space is formed between the hood and the heat shield plate. Thus, the post-processing device can be operated in a high temperature environment, while insulating the inside of the engine compartment below the heat shield plate from outer air. The operating seat can be prevented from being heated by the heat emitted from the engine compartment, with the heat in the engine compartment under the hood shielded by the hood shield plate. With a gap provided between the hood shield plate and the heat shield plate, the heat is less likely to accumulate in the engine compartment. Thus, the heat damage on the post-processing device itself, the hood, and the like can be prevented.

In the embodiment of the invention according to the present application, the hood pivots about the upper end position of the hood shield plate to be opened and closed. Thus, the hood can be largely opened rearward, so that the operator can easily access inside the engine compartment. All things considered, the operator can not only perform a maintenance work easily but can also perform the maintenance safely and the like by being prevented from coming into contact with the hood.

In the embodiment of the invention according to the present application, the heat in the engine compartment below the hood is shielded by the hood shield plate. Thus, the operating seat can be prevented from being heated by heat emitted from the engine compartment, whereby the operator on the operating seat can comfortably operate the vehicle without being affected by exhaust heat from the engine and the post-processing device. The operating seat and the hood are separated from each other. Thus, the hood may have a large outer dimension and can still be sufficiently opened. As described above, even when the engine compartment incorporates a heat emitting member such as the post-processing device, with a large volume achieved in the hood, the hood can be less affected by heat emitted from the post-processing device.

In the embodiment of the invention according to the present application, the engine covers having an entire surface in a porous form are disposed on both sides of the engine. Thus, the air heated by the engine and the post-processing device can be discharged outside. The engine cover has an upper end position positioned below the post-processing device. Thus, a high temperature maintaining effect for the post-processing device can be achieved with the hood, so that a regeneration operation can be performed under high temperature.

In the embodiment of the invention according to the present application, the heat in the engine compartment below the hood is shielded by the hood shield plate. Thus, the operating seat can be prevented from being heated by heat emitted from the engine compartment, whereby the operator on the operating seat can comfortably operate the vehicle without being affected by exhaust heat from the engine and the post-processing device. The space is formed between the hood and the heat shield plate. Thus, the post-processing device can be operated in a high temperature environment, while insulating the inside of the engine compartment below the heat shield plate from outer air.

In the embodiment of the invention according to the present application, a flow of the cooling air taken in through the openings on the side of the radiator toward the rear side is shielded by the shielding plate, so that the cooling air can be sent to the front surface side of the radiator. Thus, an amount of cooling air passing through the radiator can be increased, whereby the radiator can efficiently be cooled by air. The cooling air is efficiently blown to the engine by the cooling fan surrounded by the fan shroud. Thus, a relaxed heat environment can be achieved around the engine even when the post-processing device that serves as a high temperature heat source is provided.

In the embodiment of the invention according to the present application, when the hood is closed, the shielding plate and the side shielding portions are positioned on the rear side of the opening on the side surface, and the upper shielding portion is positioned on the rear side of the opening of the ceiling portion. Thus, a large amount of cooling air can be taken into the radiator. Thus, a high effect of cooling various cooling members such as the radiator and an intercooler disposed on the front side of the engine compartment can be achieved. A large amount of cooling air can be taken in by the cooling fan surrounded by the fan shroud. Thus, the cooling air can be supplied to the engine that serves as the heat emitting member, whereby an excellent heat balance can be achieved in the engine compartment.

