Patent Description:
Conventionally, there is known a working vehicle in which an engine is mounted on a rear portion of a running vehicle, and a radiator and a radiator fan are attached to an inner side of a cover that opens and closes an engine room for accommodating the engine (see <CIT>).

However, in the above conventional working vehicle, the accessibility to the radiator, maintenance and assembly are improved, but there is a possibility that the air flow stays and sufficient cooling performance for the engine cannot be obtained.

<CIT> and <CIT> disclose a riding lawn mower as specified in the preamble of claim <NUM>.

The invention has been made in view of the above situations, and an object thereof is to provide a riding lawn mower in which an engine can be sufficiently cooled.

In order to solve the above-described problems and achieve the object, there is provided a riding lawn mower as specified in claim <NUM>.

According to the riding lawn mower specified in claim <NUM>, the engine can be sufficiently cooled.

Hereinafter, an embodiment of a riding lawn mower disclosed in the present application will be described in detail with reference to the accompanying drawings. The invention is not limited to the embodiments described below.

First, an overall configuration of a riding lawn mower <NUM> will be briefly described with reference to <FIG>. <FIG> is a side view of the riding lawn mower <NUM> according to an embodiment, <FIG> is a schematic view of the riding lawn mower <NUM>, and <FIG> is an explanatory view showing in detail an engine room <NUM> provided in a running vehicle body <NUM> of the riding lawn mower <NUM>. In <FIG>, the inside of the engine room <NUM> is shown in a sectional view.

The riding lawn mower <NUM> is operated by an operator (also referred to as a worker) who is seated on a driver's seat <NUM> provided in a front portion of the running vehicle body <NUM> having a vehicle body frame <NUM>. In the following, a front and rear direction refers to a running direction when the riding lawn mower <NUM> goes straight. The front side in the running direction is defined as "the front," and the rear side is defined as "the rear. " The running direction of the riding lawn mower <NUM> refers to a direction from the driver's seat <NUM> toward a steering wheel <NUM> when the riding lawn mower <NUM> goes straight.

Further, a left and right direction refers to a direction that is horizontally orthogonal to the front and rear direction. In the following description, the left and right are defined toward "the front" side. That is, the left hand side refers to "the left" and the right hand side refers to "the right" with an operator seated on the driver's seat <NUM> and facing forward. Further, an upper and lower direction refers to a vertical direction. The front and rear direction, the left and right direction, and the upper and lower direction are three-dimensionally orthogonal to each other. The respective directions are defined for the sake of easy understanding of the description, and the invention is not limited to these directions. In the following, the riding lawn mower <NUM> may be referred to as a machine body.

As shown in <FIG>, the riding lawn mower <NUM> includes, as a pair of left and right running wheels, a pair of left and right front wheels <NUM> at the front portion of the running vehicle body <NUM> and a pair of left and right rear wheels <NUM> at the rear portion of the running vehicle body <NUM>.

Further, the riding lawn mower <NUM> includes a mower device <NUM> in front of the lower portion of the running vehicle body <NUM> (see <FIG>). The mower device <NUM> has a cutting blade <NUM> that rotates around a vertical axis (an axis extending in the upper and lower direction in <FIG>), and a motor <NUM> that drives the cutting blade <NUM>. The mower device <NUM> is vertically movably attached to the front of the running vehicle body <NUM> via a mower lifting device <NUM> (see <FIG>).

Further, the riding lawn mower <NUM> includes a control part <NUM> at the front portion of the running vehicle body <NUM>. The control part <NUM> includes the driver's seat <NUM>, a floor step <NUM>, a steering column <NUM>, and the steering wheel <NUM>. The floor step <NUM> is provided in front of the driver's seat <NUM>. The steering column <NUM> is erected on the front portion of the floor step <NUM>. The steering wheel <NUM> is provided above the steering column <NUM>. In addition to the steering wheel <NUM>, an operation panel <NUM>, various operation levers <NUM>, various operation switches, and the like are provided above the steering column <NUM>. Further, a safety bar <NUM> is provided at the rear portion of the control part <NUM> so that it can be tilted back and forth.

Further, a collector <NUM> is provided behind the driver's seat <NUM> on the running vehicle body <NUM>. That is, the collector <NUM> that is a grass collection container for storing grass or the like (hereinafter, referred to as grass) cut by the mower device <NUM> is vertically movably mounted above a bonnet <NUM> (see <FIG>) covering the engine room <NUM> via a lifting arm <NUM>, as shown in <FIG>. The lifting arm <NUM> constitutes a collector lifting device <NUM> (see <FIG>) together with a lifting cylinder and the like (not shown).

Further, as shown in <FIG> and <FIG>, on the rear side of the driver's seat <NUM> (see <FIG>) in the riding lawn mower <NUM>, the engine room <NUM> is formed below the collector <NUM>, and an engine <NUM> is mounted in the engine room <NUM>. Further, the riding lawn mower <NUM> includes the bonnet <NUM> that is provided at an upper portion of the engine room <NUM> and covers the engine <NUM>. As shown, an engine fan <NUM> is attached to the bonnet <NUM>. The bonnet <NUM> will be described in detail later. Further, a radiator <NUM> is arranged on the side of the engine <NUM> and on the back side of the plane of <FIG> (see <FIG>).

The engine <NUM> and an exhaust gas purification device <NUM> for purifying exhaust gas from the engine <NUM> are arranged in parallel inside the engine room <NUM>. The exhaust gas purification device <NUM> is provided in the middle of an exhaust pipe <NUM> (see <FIG>) that guides the exhaust gas from the engine <NUM> to the outside of the machine body.

The engine <NUM> in the present embodiment is a diesel engine with a supercharger (turbocharger). However, the engine <NUM> may not have a supercharger.

The exhaust gas purification device <NUM> has a well-known structure. The exhaust gas purification device <NUM> has a filter called a DPF (Diesel Particulate Filter) housed therein, and collects particles by allowing the exhaust gas to pass through the DPF. Further, since the DPF may be clogged due to the accumulation of the collected particles, the exhaust gas purification device <NUM> has a regeneration function of burning out the accumulated particles.

Further, the riding lawn mower <NUM> includes an air cleaner <NUM> for supplying clean air to the engine <NUM>. The air cleaner <NUM> is connected to a pre-cleaner <NUM> arranged on the upper left side of the driver's seat <NUM>. The pre-cleaner <NUM> is fixed to a machine body frame.

Further, the air cleaner <NUM> in the present embodiment is provided near the outside of the machine body, as shown in <FIG>. Therefore, the degree of freedom in arrangement is higher than when the air cleaner <NUM> is provided inside the machine body.

Further, the riding lawn mower <NUM> includes a transmission case <NUM> to which power from the engine <NUM> is transmitted. The transmission case <NUM> is arranged below the engine <NUM> on the side of the driver's seat <NUM>. In the riding lawn mower <NUM> according to the present embodiment, the exhaust gas purification device <NUM> is arranged above the transmission case <NUM>. With this configuration, the exhaust gas purification device <NUM> can be arranged at a position as low as possible without causing a dead space in the engine room <NUM>.

In this way, although the riding lawn mower <NUM> according to the present embodiment includes the collector <NUM>, and accordingly, has a higher center of gravity, the exhaust gas purification device <NUM> can be arranged at a lower position. Therefore, the riding lawn mower <NUM> enables stable running by lowering the position of the center of gravity as a whole.

Further, as shown in <FIG>, the riding lawn mower <NUM> includes a blower case <NUM> having a blower <NUM> installed therein. The blower case <NUM> and the collector <NUM> are connected by a duct <NUM>. Further, a shooter <NUM> is provided between the blower <NUM> and the mower device <NUM>.

Thus, in the riding lawn mower <NUM>, the grass cut by the mower device <NUM> is sent from a mower deck <NUM> shown in <FIG> to the blower <NUM> via the shooter <NUM>, and is further pneumatically conveyed to the collector <NUM> via the duct <NUM>.

As shown in <FIG>, a grass outlet <NUM> is formed at the end of the duct <NUM>. The grass outlet <NUM> serves as a connecting portion with the collector <NUM>. That is, when the collector <NUM> is in a lowered normal position, the grass outlet <NUM> overlaps an inlet (not shown) of the collector <NUM>, and the duct <NUM> and the collector <NUM> are connected. The grass cut by the mower device <NUM> is sent into the collector <NUM> via the shooter <NUM> and the duct <NUM> by the blower <NUM>.

Next, a transmission configuration of the riding lawn mower <NUM> will be briefly described with reference to <FIG> is a transmission line diagram of the riding lawn mower <NUM> according to the embodiment. As shown in <FIG>, in the riding lawn mower <NUM>, the power (rotational power) output from the engine <NUM> is transmitted to a distribution transmission shaft <NUM> connected to an output shaft <NUM> of the engine <NUM>, and is transmitted to a first PTO (Power Take-off) shaft (also referred to as a blower PTO shaft) 12A. The rotational power output from the blower PTO shaft 12A is transmitted to the above-described blower <NUM> via a blower transmission device (gear transmission device or the like), for example. In <FIG>, reference numerals 16A, 16B indicate PTO clutches.

Further, the rotational power output from the distribution transmission shaft <NUM> is transmitted to driving wheels via a running transmission. That is, through a hydraulic pump 13a of a hydraulic continuously variable transmission (hereinafter, also referred to as HST (Hydro Static Transmission)) <NUM> accommodated in the transmission case <NUM>, a trunnion shaft tilts to shift a hydraulic motor 13b.

By the way, the riding lawn mower <NUM> is configured to be switchable between two-wheel drive (2WD) and four-wheel drive (4WD). Therefore, when the riding lawn mower <NUM> is driven in 2WD, one (e.g., the left and right front wheels <NUM>) of the left and right front wheels <NUM> and the left and right rear wheels <NUM> becomes driving wheels. When the riding lawn mower <NUM> is driven in 4WD, the left and right front wheels <NUM> and the left and right rear wheels <NUM> become driving wheels.

In case of 4WD, the rotational power output from the distribution transmission shaft <NUM> is transmitted to the front wheels <NUM> via the hydraulic pump 13a and the hydraulic motor 13b of the HST <NUM> and via a gear transmission 14a and a differential gear mechanism 14b in a differential gear case <NUM>. Further, the rotational power output from the distribution transmission shaft <NUM> is transmitted to the rear wheels <NUM> via the hydraulic pump 13a and the hydraulic motor 13b of the HST <NUM> and via a gear transmission 15a and a differential gear mechanism 15b in a differential gear case <NUM>.

Further, the rotational power output from the distribution transmission shaft <NUM> is transmitted to a second PTO shaft (also referred to as a mower PTO shaft) 12B. The rotational power output from the mower PTO shaft 12B is transmitted to the above-described cutting blade via a mower input shaft <NUM> shown in <FIG> and a mower transmission (not shown) in the mower deck <NUM>.

Here, a control system of the riding lawn mower <NUM> centering on a control part <NUM> will be described with reference to <FIG> is a block diagram centering on the control part <NUM> of the riding lawn mower <NUM>.

The control part <NUM> can control each unit including various actuators <NUM> provided in the riding lawn mower <NUM> by electronic control, and includes a processing unit having a CPU (Central Processing Unit) and the like.

Further, the control part <NUM> includes a storage unit <NUM> that stores a program for controlling the drive of a first fan motor <NUM> that drives the engine fan <NUM> and a second fan motor <NUM> that drives a radiator fan <NUM> and data necessary for driving the various actuators <NUM> and the like. The storage unit <NUM> includes a hard disk, a ROM (Read Only Memory), a RAM (Random Access Memory), and the like.

Further, the control part <NUM> includes an engine ECU (Electronic Control Unit) <NUM>, a running system ECU <NUM>, and a working machine system ECU <NUM>.

The engine ECU <NUM> controls the output or the like of the engine <NUM>, and the running system ECU <NUM> controls the continuously variable transmission <NUM> or the like, thereby controlling the overall running of the machine body. The working machine system ECU <NUM> controls the overall driving of the mower device <NUM>. The working machine system ECU <NUM> controls a solenoid valve or the like for turning on and off the PTO clutches 16A, 16B (see <FIG>) and also controls the mower lifting device <NUM> to control the lifting and lowering of the mower device <NUM>.

Further, the control part <NUM> is connected with a combustion system sensor <NUM>, a vehicle speed sensor <NUM>, a PTO sensor <NUM>, a differential pressure sensor <NUM>, an airflow sensor <NUM>, a DPF sensor <NUM>, and other various sensors <NUM>.

The combustion system sensor <NUM> detects the combustion state of the engine <NUM>. The vehicle speed sensor <NUM> is provided to calculate the running speed (vehicle speed) of the machine body, and derives a measured value of the vehicle speed from the rotational speeds of the front wheels and the rear wheels. The PTO sensor <NUM> detects the rotation of the blower PTO shaft 12A and the mower PTO shaft 12B (see <FIG>).

The differential pressure sensor <NUM> is provided to detect the exhaust pressure before and after the exhaust gas purification device <NUM> connected in the middle of the exhaust pipe <NUM> (see <FIG>). The airflow sensor <NUM> is a sensor for detecting the amount of air supplied to the engine <NUM> and is provided in the air cleaner <NUM>. The DPF sensor <NUM> detects the degree of clogging of the DPF accommodated in the exhaust gas purification device <NUM>.

In this manner, the control part <NUM> acquires various data in each unit, and controls the operation of each unit of the machine body based on the data and the result calculated from the data and the like.

Next, a mounting structure of the exhaust gas purification device <NUM> will be specifically described with reference to <FIG> and <FIG>. <FIG> is an explanatory view of the exhaust gas purification device <NUM> provided in the riding lawn mower <NUM>, and <FIG> is an explanatory view of a connector <NUM> for mounting the exhaust gas purification device <NUM>.

As shown in <FIG>, the exhaust gas purification device <NUM> has a cylindrical body portion <NUM> that is a body portion of the exhaust gas purification device. An upstream side exhaust pipe <NUM> of the exhaust pipe <NUM> is connected to one end of the body portion <NUM>, and a downstream side exhaust pipe <NUM> of the exhaust pipe <NUM> is connected to the other end.

By the way, in the present embodiment, a leading end of the exhaust pipe <NUM> (the downstream side exhaust pipe <NUM>) has an exhaust port opening toward the left side of the machine body. However, it is preferable to provide a diffuser at the exhaust port. With this configuration, there is no danger of ignition of abandoned grass due to hot exhaust gas.

When the mower device <NUM> is configured to discharge the mowed grass laterally and there is no danger of ignition of the abandoned grass left behind, the leading end of the exhaust pipe <NUM> (the downstream side exhaust pipe <NUM>) may be opened to the rear of the machine body. In that case, the degree of freedom in designing the shape of the exhaust pipe <NUM> is increased, and the piping can be installed in parallel so that water is not collected.

Further, as shown in <FIG>, the exhaust gas purification device <NUM> is arranged at a height that does not protrude upward from the upper end of the engine <NUM>. At that time, the exhaust gas purification device <NUM> is connected to an upper portion of the transmission case <NUM> via the predetermined connector <NUM>.

As shown in <FIG>, the connector <NUM> includes a pair of ring-shaped holder portions <NUM>, <NUM> for holding the body portion <NUM> of the exhaust gas purification device <NUM>, and a stay portion <NUM> to which the holder portions <NUM>, <NUM> are attached and in which a connecting portion <NUM> with the transmission case <NUM> is formed.

Further, the stay portion <NUM> has a first stay member <NUM> connected to the transmission case <NUM>, and a pair of second stay members <NUM>, <NUM> connected to the holder portion <NUM>, respectively.

The first stay member <NUM> is formed in a substantially U-shape that has a flat plate-shaped bottom plate portion serving as the connecting portion <NUM> and upright pieces <NUM>, <NUM> rising from both ends of the bottom plate portion. Further, the first stay member <NUM> can be connected to an upper portion of a flange portion <NUM> of the transmission case <NUM> at the connecting portion <NUM> by bolts <NUM>, <NUM>.

The pair of left and right second stay members <NUM> are connected to the first stay member <NUM> by connecting screws <NUM>, respectively. The holder portion <NUM> is welded to one side edge of the second stay member <NUM> formed in an arc shape.

The holder portion <NUM> includes a semi-circular first holder <NUM> and a semi-circular second holder <NUM> abutted against and connected to the first holder <NUM> by screws <NUM>, <NUM>. The first holder <NUM> is welded to the second stay member <NUM>.

With this configuration, the first holder <NUM> and the second holder <NUM> can firmly hold the substantially cylindrical body portion <NUM> of the exhaust gas purification device <NUM>. Further, when the screws <NUM> are loosened, the body portion <NUM> can be rotated in a circumferential direction and its mounting angle can be adjusted. In this way, the positioning of the body portion <NUM> is also easy, and thus, work such as piping connection is also easy.

Further, the stay portion <NUM> is divided into the first stay member <NUM> connected with the transmission case <NUM> and the second stay members <NUM> connected with the holder portions <NUM>, respectively. Therefore, when the first stay member <NUM> is connected to the transmission case <NUM> in advance, it is easy to install the exhaust gas purification device <NUM> later and it is also easy to dismount it after the installation, so that maintenance is improved.

In this way, although the riding lawn mower <NUM> in the present embodiment includes the collector <NUM>, and accordingly, has a higher center of gravity, the exhaust gas purification device <NUM> can be located as low as possible in the engine room <NUM> where the devices are generally densely installed. Therefore, it is possible to prevent the center of gravity from becoming higher even when the exhaust gas purification device <NUM> is provided, so that the driving stability can be secured.

By the way, the connector <NUM> may have a configuration described below. <FIG> is an explanatory view showing a modification of the connector <NUM>. That is, as shown in <FIG>, the connector <NUM> according to the modification includes an upper stay member <NUM> and a lower stay member <NUM> that are vertically separable. The semi-circular first holder <NUM> is welded to the upper stay member <NUM>. The configuration of the holder portion <NUM> is similar to that shown in <FIG>. The holder portion <NUM> includes the semi-circular first holder <NUM> and the semi-circular second holder <NUM> abutted against and connected to the first holder <NUM> by the screws <NUM>, <NUM>.

The connecting screws <NUM> can be similarly used to connect the upper stay member <NUM> and the lower stay member <NUM>. At this time, the connecting screws <NUM> are welded to the lower stay member <NUM> to form weld buttons. The connecting screws <NUM> can be passed through connecting holes formed in the upper stay member <NUM> and can be tightened with nuts or the like. In this way, it is easy to assemble the upper stay member <NUM> and the lower stay member <NUM>.

The connector <NUM> is configured such that the stay portion is separable like the first stay member <NUM> and the second stay member <NUM>, or the upper stay member <NUM> and the lower stay member <NUM>. Therefore, for example, when the first stay member <NUM> or the lower stay member <NUM> is fixed to the transmission case <NUM> in advance, the second stay member <NUM> or the upper stay member <NUM>, to which the holder portions <NUM> that hold the exhaust gas purification device <NUM> are connected, can be easily attached to the transmission case <NUM>.

Further, as shown in <FIG>, the riding lawn mower <NUM> according to the present embodiment includes a device cover <NUM> that covers the exhaust gas purification device <NUM>. That is, as shown in <FIG>, the engine fan <NUM>, which will be described in detail later, is provided above the exhaust gas purification device <NUM>, and the DPF accommodated in the exhaust gas purification device <NUM> needs to burn the deposited particles, as described above. At that time, the device cover <NUM> is provided to maintain the DPF in a high temperature state, so that the DPF can be protected from the wind of the engine fan <NUM>.

As shown in <FIG>, the device cover <NUM> has a flat surface portion <NUM> and a hanging portion <NUM> formed by bending a long side portion of the flat surface portion <NUM> downward. The device cover <NUM> is shaped to enclose the exhaust gas purification device <NUM>. Therefore, for example, the device cover <NUM> prevents grass and the like from falling from above to the exhaust gas purification device <NUM>, thereby preventing the occurrence of a fire or the like in advance. Further, for example, harnesses, hydraulic hoses, and the like are arranged above the flat surface portion <NUM> and protected from the heat of the DPF when the DPF becomes hot.

Further, the hanging portion <NUM> serves as a baffle plate that guides the wind from the engine fan <NUM> to the engine <NUM> while keeping the wind away from the exhaust gas purification device <NUM>. Although the hanging portion <NUM> in the present embodiment is bent in a substantially vertical direction, the bending angle of the hanging portion <NUM> can be set to an appropriate angle.

Further, the device cover <NUM> is provided with a shielding plate portion <NUM> on the side opposite to the hanging portion <NUM> so that hot wind does not flow to the driver's seat <NUM>. The shielding plate portion <NUM> can prevent a driver sitting on the driver's seat <NUM> from being exposed to hot wind, thereby preventing discomfort to the driver.

Next, the engine fan <NUM> and the radiator fan <NUM> will be described with reference to <FIG>. <FIG> is an explanatory view showing an arrangement of the bonnet <NUM> covering the engine room <NUM> and the radiator fan <NUM>, <FIG> is an explanatory view of the bonnet <NUM>, and <FIG> is an explanatory view of the engine fan <NUM> provided on the back side of the bonnet <NUM>.

First, the radiator <NUM> and the radiator fan <NUM> will be described. As shown in <FIG>, the radiator <NUM> is provided on the right side of the machine body (on the right side of the engine <NUM>). Further, the radiator fan <NUM> is provided on the inner side of a radiator net <NUM> that is provided on the outer side of the radiator <NUM> to prevent entrance of dust. That is, the radiator fan <NUM> for blowing air to the radiator <NUM> is arranged adjacent to the side of the radiator <NUM>.

Although not shown, a pipe of a fuel cooler is arranged along an outer surface of the radiator <NUM> so that it can be cooled by the radiator fan <NUM>. The pipe of the fuel cooler includes a supply pipe and a return pipe, both of which are vertically arranged along the outer surface of the radiator <NUM>.

Further, the bonnet <NUM> is provided above the engine room <NUM> so that it can be opened and closed up and down via a hinge portion <NUM>. That is, the bonnet <NUM> has a substantially rectangular shape and includes a plate-like body <NUM> having a surface facing the engine <NUM>. An air intake portion <NUM> having a plurality of vent holes <NUM> and a cover portion <NUM> covering the upper portion of each vent hole <NUM> is formed in the plate-like body <NUM>. A plurality of the air intake portions <NUM> are provided in two rows between a pair of slits <NUM>, <NUM> provided in parallel along a longitudinal direction of the plate-like body <NUM>. Further, a handle <NUM> is formed on the front side of the surface of the plate-like body <NUM>, and the hinge portion <NUM> is provided at the rear end of the plate-like body <NUM>.

The vent hole <NUM> is formed in an elongated rectangular shape facing the engine <NUM>, and the cover portion <NUM> is formed in a shape rising diagonally rearward from a long side portion on the front side of the vent hole <NUM>.

Further, as shown in <FIG>, the engine fan <NUM> is attached to the back side of the plate-like body <NUM>. That is, the engine fan <NUM> for blowing air to the engine <NUM> is arranged above the engine <NUM>. The same fan can be used for the engine fan <NUM> and the radiator fan <NUM>, so that the parts management can be rationally done and cost reduction can be achieved.

The engine fan <NUM> is connected to the first fan motor <NUM>. The engine fan <NUM> and the first fan motor <NUM> are connected together to a guard body <NUM> for protecting the engine fan <NUM>. The guard body <NUM> is connected to a cut-and-raised piece cut and raised to form the slit <NUM>.

In this manner, the engine fan <NUM> is provided on the back side of the bonnet <NUM> where the air intake portions <NUM> are formed, and, as shown in <FIG>, the engine fan <NUM> and the engine <NUM> are arranged to face each other. Therefore, the outside air can be efficiently drawn into the engine room <NUM>, and the engine <NUM> can be efficiently cooled.

The collector <NUM> for storing grass is arranged above the bonnet <NUM>. However, since the air intake portion <NUM> is provided with the cover portion <NUM> covering the vent hole <NUM>, it is possible to prevent grass or the like from entering the engine room <NUM> as much as possible.

Moreover, as described above, the grass outlet <NUM>, which is a connecting portion between the collector <NUM> and the duct <NUM>, is provided in front of the vent hole <NUM>, and the cover portion <NUM> is formed in a shape rising diagonally rearward from the front side of the vent hole <NUM>. Therefore, it is possible to more efficiently prevent grass or the like from entering the engine room <NUM>.

As described above, the riding lawn mower <NUM> according to the present embodiment includes the engine fan <NUM> and the radiator fan <NUM>. The engine fan <NUM> and the radiator fan <NUM> are configured such that one of both rotates in a suction direction and the other rotates in a blowing direction.

In the present embodiment, the radiator fan <NUM> rotates in the suction direction and the engine fan <NUM> rotates in the blowing direction. Therefore, the engine <NUM> and the radiator <NUM> in the engine room <NUM> can be efficiently cooled. That is, since the flow without heated air staying can be generated between the side and the upper side of the engine <NUM>, the engine <NUM> can be sufficiently cooled.

Further, as shown in <FIG>, the engine fan <NUM> and the radiator fan <NUM> are drive-controlled by the control part <NUM> and can be reversed in the forward and reverse directions according to predetermined conditions. For example, when the exhaust gas purification device <NUM> performs the combustion function (post-treatment regeneration) of the DPF, the control part <NUM> can rotate the radiator fan <NUM> in the blowing direction and rotate the engine fan <NUM> in the suction direction.

By controlling in this way, during the post-treatment regeneration of the DPF, the dust accumulated on the radiator net <NUM> can be blown out and removed by reversing the flow of air. Further, when the forward and reverse directions are switched in conjunction with the post-treatment regeneration of the DPF, the wind for blowing out dust becomes easier to pass through the radiator net <NUM>, and dust can be efficiently removed.

Further, even when the engine fan <NUM> rotates in the suction direction, the control part <NUM> can rotate the engine fan <NUM> in the blowing direction when the collector <NUM> is raised. With this control, it is possible to prevent the grass that has fallen from the collector <NUM> from entering the engine room <NUM>.

In this way, in the riding lawn mower <NUM> according to the present embodiment, it is possible to appropriately cool the engine <NUM> according to its driving state and the like.

Although the riding lawn mower <NUM> according to the present embodiment has the above-described configuration, for example, an inclined portion may be provided in a return portion from a breather (not shown) of the engine <NUM> so that oil return or the like does not occur in the airflow sensor <NUM> provided in an intake path (not shown) from the pre-cleaner <NUM> to the engine <NUM>.

Further, in the present embodiment, the engine <NUM> has a supercharger, so that there is no problem even when the intake path to the engine <NUM> becomes long, and the degree of freedom in designing the air supply path is increased. However, when the engine has no supercharger, it is preferable that the air supply path is as short as possible. In that case, the pre-cleaner <NUM> may be arranged near the air cleaner <NUM> to shorten the air supply path.

Further, it is preferable that a hose of the return portion from the breather is made of oil-resistant AEM (ethylene/acrylic/rubber) in order to increase resistance to oil vapor.

Claim 1:
A riding lawn mower (<NUM>) comprising:
a running vehicle body (<NUM>) which comprises running wheels (<NUM>, <NUM>) and to which a mower device (<NUM>) can be connected;
an engine (<NUM>) mounted on the running vehicle body (<NUM>);
a radiator (<NUM>);
a radiator fan (<NUM>) arranged near the radiator (<NUM>) for blowing air to the radiator (<NUM>); and
an engine fan (<NUM>) for blowing air to the engine (<NUM>),
characterized in that
the engine fan (<NUM>) is arranged above the engine (<NUM>), and
the radiator fan (<NUM>) is a provided on a side of the engine (<NUM>) facing in a direction horizontally orthogonal to a front and rear direction of the riding lawn mower (<NUM>).