JP2023073581A - work vehicle - Google Patents

Abstract

To provide a work vehicle which can prevent appearance from being deteriorated and manufacturing cost from increasing when providing a waste-heat hole on a bonnet etc so as to configure not to impart heat damage to a peripheral component by exhausting, from the waste-heat hole, heat generated by an exhaust gas post-processing device which and an engine are covered with the bonnet.SOLUTION: A work vehicle is configured to cover an exhaust gas post-processing device 16 provided above and in a rear-end approaching part of an engine, with a rear-end approaching part of the bonnet and a front-end approaching part of a spacer cover 37 in front of a heat-shield plate, and comprise the waste-heat holes 37c, 37d in a top plate part and a lateral plate of a spacer cover facing the exhaust gas post-processing device, so as to exhaust hot-air with high temperature raised by the exhaust gas post-processing device from waste-heat holes to outside the work vehicle.SELECTED DRAWING: Figure 7

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to working vehicles such as tractors and ride-on rice transplanters, and more particularly to working vehicles having an engine and an exhaust gas post-treatment device covered by a bonnet.

Diesel engines, which are installed in agricultural work vehicles and drive various parts of the aircraft, are mainly adopted because of their excellent combustion efficiency, good fuel efficiency, and strong power from low revolutions. However, the harmful particulate matter (PM) and nitrogen oxides (NOx) contained in the exhaust gas of diesel engines are regarded as a problem, and currently common rail fuel injection systems, exhaust gas recirculation systems (EGR), etc. Improvements in engine combustion technology and the adoption of exhaust gas aftertreatment devices such as diesel particulate filters (DPFs) and urea SCRs have addressed this problem.

By the way, the diesel particulate filter as the exhaust gas aftertreatment device described above collects particulate matter (mainly solid carbon particles: soot (SOOT)) in the exhaust gas and discharges it into the atmosphere. get rid of However, since the collected particulate matter clogs the filter when the accumulated amount increases, it is necessary to regenerate the filter by reburning it at a high temperature to remove it when it accumulates to a certain extent.

When regenerating this filter, the DPF becomes hot and generates heat, so the temperature inside the bonnet that covers the engine and the exhaust gas aftertreatment device rises, and the parts of the engine and DPF (sensors, rubbers, etc.) There is a risk of exceeding the heat-resistant temperature of Therefore, it is proposed to provide a heat exhaust hole in the top plate of the bonnet located above the DPF to allow the heat around the DPF to escape through the heat exhaust hole to prevent heat damage to peripheral parts due to the high temperature of the DPF. (See Patent Document 1).

In this case, the strength of the bonnet is improved by a reinforcing member provided below the heat exhaust hole, and the reinforcing member is formed as a plate member having a substantially U-shaped cross section to prevent rain or the like from entering through the heat exhaust hole. The reinforcement member receives water droplets to prevent water from splashing on the DPF, which may hinder the regeneration of the filter, turn into water vapor and deteriorate the forward visibility from the driver's seat, or cause rust on the DPF and peripheral parts. is eliminated.

In this work vehicle, a partition wall composed of a heat shield plate and a spacer cover covering the outer peripheral side of the heat shield plate is provided behind the bonnet. improve sexuality. In other words, the radiator that cools the cooling water of the engine cools the cooling water by exchanging heat with the cooling air sucked by the cooling fan, and the cooling air (exhaust air) that has become hot due to this cools the cooling air (exhaust air) inside the hood. If it is left as it is, there is a risk that the control unit will become hot. However, the partition blocks the flow of the exhaust air, preventing the control section from becoming hot.

JP 2014-117963 A

As described above, in the work vehicle, the bonnet covering the engine and the like and the control section including the steering handle and the driver's seat are partitioned by a partition formed by a heat shield plate and a spacer cover covering the outer peripheral side of the heat shield plate, or The front panel of the cabin separates the bonnet from the control section, shielding the control section from hot air discharged from the rear of the bonnet that covers the engine, etc., improving the comfort of the driver in the control section. Let

In addition, in the work vehicle, the control section is supported with anti-vibration in order to improve the riding comfort of the driver against travel vibration, vehicle body vibration, and the like. For this reason, the driving section, which covers the engine, etc. with a bonnet, and the control section, which has the driver's seat, etc., have different vibration systems, and it is necessary to separate them so that they do not transmit each other's vibrations. In this case, the spacer cover hides the heat shield plate and the like to improve the appearance, and at the same time, a cushioning material such as a seal is provided to close the gap between the front portion of the control section and the control section.

On the other hand, if an exhaust gas aftertreatment device is installed inside the bonnet together with the engine in such an environment, the rear part of the bonnet is blocked by the bulkhead or the front panel of the cabin as described above, so an exhaust gas aftertreatment device is generated. The heat generated is trapped in the upper part of the bonnet near the rear and causes heat damage to peripheral parts. Therefore, as described in Patent Literature 1, it has been proposed to provide heat exhaust holes in the top plate of the bonnet and exhaust the trapped hot air through the heat exhaust holes.

However, if heat exhaust holes are provided in the top plate of the bonnet located above the exhaust gas aftertreatment device, the temperature around the exhaust gas aftertreatment device can be lowered, but the strength of the bonnet is not sufficient to provide the heat exhaust holes. Therefore, it is necessary to improve the strength of the bonnet with a reinforcing member. In addition, there is a problem that the heat exhaust holes provided in the bonnet and the punching metal that closes the heat exhaust holes deteriorate the appearance, and the heat exhaust holes, the reinforcing member, or the punching metal increase the production cost of the bonnet.

In addition, the reinforcing member provided under the heat exhaust hole of the bonnet is formed as a plate member having a substantially U-shaped cross section, and the reinforcing member receives water droplets such as rain that enter from the heat exhaust hole, and the reinforcing member receives water droplets such as rain, and the exhaust gas aftertreatment device. In order to prevent water splashing, it is necessary to use a reinforcing member with a substantially U-shaped cross section, and it is necessary to drop water droplets out of the machine along the intermediate plate, inclined plate, and side wall or side plate of the bonnet. However, it is not clear whether water will not splash on the exhaust gas aftertreatment device or whether water droplets will surely fall out of the machine.

In view of the above problems, the present invention provides a configuration in which the heat generated by the exhaust gas aftertreatment device, which is covered with the engine by the bonnet, is exhausted through the heat exhaust hole so as not to cause heat damage to peripheral parts. An object of the present invention is to provide a work vehicle capable of preventing deterioration in appearance and deterioration in manufacturing cost when a heat exhaust hole is provided in a bonnet or the like.

In order to solve the above problems, the work vehicle of the present invention firstly separates a bonnet covering an engine and an exhaust gas aftertreatment device from a control section having a steering handle and a driver's seat by a heat shield plate, and the heat shield plate In a work vehicle in which the outer peripheral side of is covered by a spacer cover, the exhaust gas aftertreatment device provided above the rear side of the engine is covered by the rear side of the bonnet and the front side of the spacer cover in front of the heat shield plate, and the exhaust gas A heat exhaust hole is provided in the top plate portion and the side plate portion of the spacer cover facing the aftertreatment device, and hot air heated by the exhaust gas aftertreatment device is exhausted to the outside of the machine through the heat exhaust hole. Characterized by

Secondly, in the work vehicle of the present invention, a mounting plate for the exhaust aftertreatment device is erected on the rear portion of the engine, and a support plate for mounting the rear portion of the bonnet is attached to the mounting plate. It is characterized in that the exhaust gas aftertreatment device is covered with an upper portion near the rear portion thereof so that rainwater entering through the heat exhaust hole of the spacer cover does not fall on the exhaust gas aftertreatment device.

Thirdly, the work vehicle of the present invention is configured as a heat shield plate for partitioning the bonnet and the control section by providing a heat shield plate piece on the mounting plate of the exhaust gas aftertreatment device and the support plate for mounting the rear portion of the bonnet. In addition, an upper heat shield plate piece extending rearward and upward is provided on the downward inclined surface facing the rear of the support plate to which the rear part of the bonnet is attached, and the side view formed by the inclined surface of the support plate and the upper heat shield plate piece is characterized in that a substantially V-shaped space is formed as a reservoir for rainwater entering from the heat exhaust hole of the spacer cover.

Fourthly, the working vehicle of the present invention is characterized in that a drain hose is provided at the bottom of the rainwater reservoir, and rainwater accumulated in the reservoir is guided to the ground and drained by the drain hose. . Fifthly, in the work vehicle of the present invention, seals are provided at the front and rear ends of the spacer cover, which is formed in a substantially inverted U shape by the top plate portion and the side plate portions provided with the heat exhaust holes. It is characterized by eliminating a gap generated between the rear end of the bonnet and the front end of the control section by the seal. Sixthly, the work vehicle of the present invention is characterized in that the top plate portion of the spacer cover is inclined downward toward the rear.

According to the work vehicle of the present invention, the bonnet covering the engine and the exhaust gas aftertreatment device and the control section including the steering handle and the driver's seat are partitioned by the heat shield plate, and the outer peripheral side of the heat shield plate is covered by the spacer cover. In the work vehicle, the exhaust gas aftertreatment device provided above the rear portion of the engine is covered by the rear side of the bonnet and the front side of the spacer cover in front of the heat shield plate, and the spacer cover faces the exhaust gas aftertreatment device. Heat exhaust holes are provided in the top plate portion and the side plate portions, and hot air heated to a high temperature by the exhaust gas post-treatment device is exhausted to the outside of the machine through the heat exhaust holes.

Therefore, the hot air heated by the heat generated by the exhaust gas aftertreatment device installed in the upper part of the rear part of the engine is placed on the exhaust air flowing backward by the cooling fan of the engine, and the heat shield plate that separates it from the control part behind it. The heat exhaust holes provided in the top plate and side plate of the spacer cover further forward allow the heat to be quickly exhausted to the outside of the machine. can be prevented.

In addition, the heat exhaust holes for exhausting hot air to the outside of the aircraft are provided in the top plate and side plate portions of the spacer cover that covers the outer peripheral side of the heat shield plate that separates the bonnet and the control section, facing the exhaust gas aftertreatment device. Even if the cover is inferior in strength due to the heat exhaust holes, the spacer cover hides the heat shield plate to improve the appearance. Since there is no problem, there is no need to reinforce it with a reinforcing material. Further, from a safety point of view, if the heat exhaust holes are formed by a plurality of slit-shaped elongated holes or the like into which hands or the like cannot be inserted, the spacer cover can be changed and the appearance can be improved.

Further, according to the work vehicle of the present invention, a mounting plate for the exhaust gas aftertreatment device is erected on the rear portion of the engine, and a support plate for mounting the rear portion of the bonnet is mounted on the mounting plate. The upper portion of the aftertreatment device near the rear is covered to prevent rainwater entering from the exhaust heat hole of the spacer cover from falling on the exhaust gas aftertreatment device.

That is, the exhaust gas aftertreatment device provided above the rear part of the engine is covered by the rear part of the bonnet and the front part of the spacer cover in front of the heat shield plate, and the heat exhaust hole provided in the top plate of the spacer cover is Since the exhaust gas post-treatment device faces above the rear portion, the rainwater that has entered the exhaust heat hole provided in the top plate of the spacer cover falls on the rear portion of the exhaust gas post-treatment device.

However, since the upper portion of the exhaust gas aftertreatment device near the rear is covered by the support plate that attaches to the rear portion of the bonnet, it is possible to prevent rainwater from falling on the exhaust gas aftertreatment device. and does not deteriorate the forward visibility. Moreover, the support plate of the bonnet can prevent rainwater from falling on the exhaust gas aftertreatment device, which is convenient because there is no need to provide a new cover for preventing rainwater from falling on the exhaust gas aftertreatment device.

Furthermore, according to the work vehicle of the present invention, the mounting plate of the exhaust gas aftertreatment device and the support plate for mounting the rear portion of the bonnet are provided with heat shielding plate pieces to form a heat shielding plate that partitions the bonnet and the control section. In addition, an upper heat shield plate piece directed rearward and upward is provided on the downward inclined surface toward the rear of the support plate to which the rear part of the bonnet is attached, and in a side view formed by the inclined surface of the support plate and the upper heat shield plate piece A substantially V-shaped space is formed as a reservoir for rainwater entering from the heat exhaust hole of the spacer cover.

Therefore, a heat shield plate that covers the substantially trapezoidal rear surface of the bonnet without gaps, a mounting plate for mounting the exhaust gas aftertreatment device on the rear part of the engine, and a support plate for mounting the rear part of the bonnet on the engine. It is possible to reduce the material cost by filling the remaining gaps with heat shield plate pieces while utilizing each plate surface of the plate.

In addition, the support plate that attaches the rear part of the bonnet to the support plate that is attached to the rear part of the bonnet is protected from rainwater that has entered through the heat exhaust holes of the spacer cover and that the support plate is used as a guide member to prevent problems such as rainwater from falling on sensors that are not waterproofed. is provided with a reservoir for storing rainwater falling on the support plate. An upper heat shield plate piece extending rearward and upward is provided on the downward inclined surface of the support plate facing the rear of the storage portion, and the inclined surface of the support plate and the upper heat shield plate piece form a substantially V shape in side view. A letter-shaped space can be configured in the rainwater reservoir.

Further, according to the work vehicle of the present invention, a drain hose is provided at the bottom of the rainwater reservoir, and the rainwater accumulated in the reservoir is guided to the ground and drained by the drain hose. Therefore, the drain hose can be used to guide the rainwater to the ground before it overflows from the reservoir, preventing the rainwater and car wash water from accumulating in the surrounding parts and causing them to rust. can do.

Further, according to the work vehicle of the present invention, seals are provided at the front and rear ends of the spacer cover, which is formed in a substantially inverted U shape by the top plate portion and the side plate portions provided with the heat exhaust holes, and the front and rear seals are provided. eliminates gaps between the rear end of the bonnet and the front end of the control section. Therefore, the seal provided at the front end of the spacer cover eliminates the gap provided to prevent shock when the bonnet opens and closes. By closing such a gap with a seal, it is possible to prevent rainwater from entering the bonnet through any part other than the aforementioned heat exhaust hole.

Moreover, according to the work vehicle of the present invention, the top plate portion of the spacer cover is inclined downward toward the rear. Therefore, if the exhaust gas aftertreatment device is installed above the rear part of the engine, the height of the rear part of the bonnet will be higher, and even if there is a step between the spacer cover and the spacer cover, this step will be removed from the top plate of the spacer cover. It can be eliminated by sloping downward toward the rear, and the rear end of the top plate of the spacer cover and the front of the control unit play the role of a drainage channel for rainwater to flow left and right, and to the heat exhaust hole Intrusion of rainwater can be reduced.

1 is a front view of a tractor; FIG. 1 is a side view of a tractor; FIG. 1 is a perspective view of an engine and a DPF provided in the engine; FIG. It is a perspective view which shows the open state of a bonnet. FIG. 10 is a perspective view of the control unit viewed from the driver's seat side; FIG. 4 is a plan view of a driving portion; It is the perspective view seen from the right rear of the motor part. It is the perspective view seen from the left rear of the motor part. FIG. 3 is a perspective view of a spacer cover; It is a longitudinal cross-sectional view of a motor part. It is a longitudinal cross-sectional view near the rear of the driving unit. FIG. 4 is a vertical cross-sectional view of a main portion in which a spacer cover is provided between the driving portion and the operating portion; It is the perspective view seen from the slanting front which shows the structure of a heat-insulating plate. It is the perspective view seen from diagonally back which shows the structure of a heat-shielding plate. It is a front view which shows upper side|approaching|deviation of the tractor of 2nd Embodiment. FIG. 11 is a plan view showing the driving portion side of the tractor of the second embodiment; FIG. 11 is a side view showing the driving portion side of the tractor of the second embodiment; FIG. 10 is a vertical cross-sectional view of a main portion in which a spacer cover of the second embodiment is provided between the driving portion and the operating portion; FIG. 3 shows a state in which a fuel filter and a water separator are attached, (a) is a perspective view showing a state covered with a cover, and (b) is a perspective view showing a state in which the cover is removed.

An embodiment of the present invention will be described based on the drawings. As shown in FIGS. 1 to 5, an agricultural tractor 1 as a working vehicle comprises an engine 2 and front and rear transmission cases 3 and 4 integrally connected to form a vehicle body (body). A front axle case 6 is rotatably supported on the underside of a chassis bracket 5 fixed to the left and right near the lower portion of the engine 2 and extending forward. Front axle cases 7 are attached to the left and right ends of the front axle case 6, respectively.

On the other hand, the rear axle cases fixed on the left and right sides of the rear transmission case 4 support the rear axles 10 respectively, and the left and right rear wheels 11 are attached to the respective rear axles 10 . A well-known three-point link mechanism comprising a top link 12 and left and right lower links 13 is provided at the rear portion of the vehicle body. This three-point link mechanism connects a work machine such as a rotary tillage device to the machine body. , and the lower link 13 are provided so as to be movable up and down via lift rods each having one end connected to the middle of the lower link 13 .

Furthermore, as shown in FIG. 3, the above-mentioned engine 2 employs a water-cooled 4-cycle diesel engine, and this engine 2 produces nitrogen oxides generated by complete combustion and incomplete combustion in accordance with the tightening of exhaust gas regulations. A common rail fuel injection system, supercharger, exhaust gas recirculation system (EGR), etc., which reduce the generation of particulate matter such as soot, are also adopted, and nitrogen oxides and particles that have not been purified by the engine itself are eliminated. Such substances are removed using a diesel oxidation catalyst (DOC) and a diesel particulate filter (diesel particulate filter: DPF) as an exhaust gas post-treatment device.

For this reason, the diesel engine 2 has a mounting plate 14 erected at the rear portion of the cylinder head, and a cylindrical DPF case 16 containing a DOC and a DPF is mounted on the front upper portion of the mounting plate 14 via a holder 15 in the longitudinal direction. is installed in the horizontal direction. Therefore, the gas discharged from the engine 2 is introduced from the lower left inlet side of the DPF case 16 provided above the rear part of the engine 2, and then through the tail pipe (not shown) from the right front outlet side of the DPF case 16. to the outside of the machine.

An auxiliary equipment bracket 17 consisting of a bottom plate and a stay is attached to the upper surface side of the chassis bracket 5. A radiator 18 for cooling cooling water of the engine 2 is attached to the auxiliary equipment bracket 17, and clean air is supplied to the engine 2. An air cleaner 19, an oil cooler 20, an intercooler 21, a battery 22, etc. are provided (see FIG. 10).

The engine 2, the DPF case 16, or engine accessories are covered by a bonnet 23. The bonnet 23 has a substantially rectangular ceiling portion 23a, left and right side plate portions 23b, and vent holes 24 on the front surface of the ceiling portion 23a. An inner grille 26 and an outer grille 27 provided with headlamps 25 and a front cover 28 provided therebelow are integrally connected by using a mounting bracket or the like. A front plate 30a of a hinge 30 having a fulcrum shaft 29 is attached to the inner rear portion of the ceiling portion 23a of the bonnet 23 with bolts, and a rear plate 30b of the hinge 30 is attached to the upper portion of the support plate 31 with bolts (see FIG. 11). ).

Furthermore, since the aforementioned support plate 31 is attached to the upper portion of the mounting plate 14 of the DPF case 16 with bolts, the bonnet 23 is a fulcrum in the left-right direction located right above the DPF case 16 provided above the rear portion of the engine 2 . It is rotatably supported around a shaft 29, and its front part is openable and closable as shown in FIG. When the bonnet 23 is removed and the front portion of the bonnet 23 is lifted, the bonnet 23 can be held in an open state by a gas spring 32 provided across the upper portion of the engine 2 and the ceiling portion 23a of the bonnet 23.

A control section is provided behind the driving section that covers the engine 2, the DPF case 16, and the like with a bonnet 23. As shown in FIG. In addition, the operator's seat 33 is provided in the center near the rear of the operator's seat. It consists of left and right fenders 35 that cover the area near the top to the top, and a safety frame 36 that is erected behind the driver's seat 33 so that it can be tilted freely.

A gate-shaped column frame 38 is erected on the front portion of the floor frame 34 described above so as to face a rear cover (spacer cover) 37 provided behind the bonnet 23 described later. A steering handle 39 for steering the left and right front wheels 9 is provided on a column mounting bracket provided near the upper part of the column frame 38 so as to be tilt-adjustable. Further, a full hydraulic power steering unit operated by the steering handle 39 is installed in the front transmission case. It is installed on the upper surface near the center of the front part of 3.

Further, as shown in FIG. 5, below the steering handle 39, a combination switch 40, a quick-up lever 41 for raising and lowering the working machine, an engine control lever 42, and a forward/reverse lever 43 are provided. is entirely covered by a cover 44 . Further, the column mounting bracket is provided with a clutch pedal 45 on the left side as viewed from the driver's seat 33, left and right brake pedals on the right side, and a parking brake lever 46 near the center.

The column mounting bracket in front of the steering handle 39 is provided with a cover for covering itself, and this cover is composed of a panel cover 47 provided near the upper portion and a rear panel cover 48 covering the rear surface near the lower portion. Among them, a meter panel 49 is attached to an opening provided on the rear surface near the upper center of the panel cover 47 so that when an operator sits on the driver's seat 33 and looks forward, the rim of the steering handle 39 and the hub can be seen. The meter panel 49 can be visually recognized from the space, and the board surface of the meter panel 49 is inclined to the panel cover 47 so as to be substantially perpendicular to the forward line of sight of the operator.

The periphery of the opening of the panel cover 47 to which the meter panel 49 is attached is formed into a visor (sunshade) that rises rearward, and the central upper surface of the meter panel 49 as a whole is inclined downward toward the front. . In addition, on the left and right sides of the opening where the cover 44 of the steering handle 39 fits behind the opening where the meter panel 49 is installed, switches for turning on and off various automatic controls (double speed, backup, turning up, etc.) and their on/off states are displayed. A left front unit provided with an LED for controlling the operation and a right front unit 50 provided with an operation switch for setting a display screen of a liquid crystal display provided in the meter panel 49 are provided.

Furthermore, a hazard lamp switch 51 and a horn switch are provided on the panel covers 47 on the upper and lower sides of the left front unit, and a starter switch 52 is provided on the panel cover 47 on the lower side of the right front unit 50 . In addition to the switches and operation levers described above, the tractor 1 is also equipped with panels provided on the left and right sides of the driver's seat 33 and the floor surface of the floor frame 34 for traveling, PTO shift levers and pedals, and lifting and lowering of the working machine. Operation tools such as position levers, various switches, and volume controls are distributed in appropriate locations.

The outline of the tractor 1 has been described above. Next, the regeneration of the diesel particulate filter (DPF) provided in the diesel engine 2 and the switch related to the regeneration will be described. It collects soot (SOOT) contained in the exhaust gas. In addition, an electronic control unit (ECU) that controls the diesel engine 2 controls the diesel particulate filter based on the exhaust temperature sensors 53 to 55 and the exhaust pressure differential pressure sensor 56 provided at the DOC inlet and the DPF inlet and outlet. Estimate the amount of deposited soot (accumulated amount ratio).

Then, the ECU of the engine 2 treats the engine 2 as normal operation when the soot accumulation amount ratio (percentage) is, for example, 0 to less than 80, and issues an automatic regeneration request when it is 80 or more. Here, if an automatic regeneration request is issued and the engine speed is high and the cooling water temperature is high, the common rail fuel injection system mixes unburned fuel into the exhaust pipe by post-injection, and this unburned fuel is injected into the diesel engine. The oxidation catalyst (DOC) causes oxidative combustion to increase the temperature of the exhaust passing through the diesel particulate filter so that the soot deposited on the diesel particulate filter can be reburned and removed from the filter.

In addition, the ECU of the engine 2 issues a manual regeneration request if the soot accumulation amount ratio is 100 or more regardless of the automatic regeneration described above. No limit control is performed, but in the latter period when the engine speed is less than 120 to 140, the engine output is reduced to 50% and the maximum speed is limited to 1500 rpm. Then, when manual regeneration is commanded by the operator, the injection amount of main injection and post injection is increased compared to automatic regeneration, the temperature of the exhaust gas is further raised, and the regeneration speed of the diesel particulate filter is accelerated.

Furthermore, the ECU of the engine 2 issues an excessive deposition request when the soot deposition ratio is 140 or more, and in this case, if the ratio is between 140 and less than 160, the engine output limit control is performed in the first stage. , the engine output is 50% and the rotation limit is set to 1500 rpm, and in the second stage after 7200 seconds, the rotation limit is set to 1200 rpm. Also, in the latter stage of 160 or more, the first stage similarly sets the engine output to 50% and sets the rotation limit to 1500 rpm, and the second stage after 3600 seconds sets the rotation limit to 1200 rpm.

When the ECU of the engine 2 regenerates the diesel particulate filter, the temperature of the exhaust gas, tail pipe, etc. becomes high, and the automatic regeneration described above cannot be performed indoors with poor ventilation or in places close to combustibles (shade of trees, vinyl houses, etc.). Since there is a risk of fire, gas poisoning, etc., in such a case, the operator can issue a command to prohibit automatic regeneration. Also, when instructing manual regeneration, move the tractor 1 to a safe, wide area outdoors with good ventilation and no flammable materials around it. Otherwise, manual regeneration cannot be performed.

Furthermore, if the above-mentioned excessive accumulation request is issued without being able to properly perform automatic regeneration or manual regeneration of the diesel particulate filter, it will be impossible for the operator to regenerate the diesel particulate filter, so the work should be done quickly. Then, the engine will be stopped and a serviceman will attempt to regenerate the engine using a service tool or the like, or in the worst case, the diesel particulate filter will be repaired or replaced.

As shown in FIG. 5, the tractor 1 has a DPF regeneration lamp and an engine lamp for notifying the DPF status (request/regeneration/abnormality) on the meter panel 49 of the panel cover 47 regarding regeneration of the diesel particulate filter as described above. Provide a fault lamp. In addition, a manual regeneration switch for commanding manual regeneration, a regeneration prohibition switch for commanding regeneration prohibition, a manual regeneration lamp for notifying the request and execution of manual regeneration, and a regeneration prohibition lamp for notifying execution of regeneration prohibition are provided.

In addition, the manual regeneration switch and manual regeneration lamp, and the regeneration prohibition switch and regeneration prohibition lamp described above each use a push button switch with an LED ball that integrates the lamp and the switch, and these two manual regeneration switches (with lamps) ) 57 and a regeneration inhibition switch (with a lamp) 58 are attached to the rear surface of a sub-panel cover 59 made of synthetic resin. The sub-panel cover 59 is provided near the center of the upper front portion of the panel cover 47, so that the meter panel 49 of the panel cover 47 and the switches and lamps provided on the sub-panel cover 59 can be Make sure it is within the forward field of view.

The regeneration of the DPF provided in the diesel engine 2 and the switch related to the regeneration have been described above. Particularly, the heated air is trapped above the bonnet 23 near the rear portion and above the spacer cover 37 near the front portion where the DPF case 16 is provided, and causes heat damage to peripheral sensors and rubber parts. Therefore, countermeasures against this problem will be described below.

First, a heat shield plate is provided between the rear portion of the bonnet 23 covering the engine 2 and the DPF case 16 and the handle frame 38 of the control section, and the warm cooling discharged by the cooling fan 60 of the engine 2 is separated by separating the two. To prevent wind (exhaust wind) from flowing to the control part side and hindering its habitability. As shown in FIGS. 6 to 12, this heat shield plate also serves as a mounting plate 14 for the DPF case 16 erected in the rear portion of the engine 2 and a support plate 31 for supporting the rear portion of the bonnet 23. Left and right heat shield plate pieces 60 attached to the support plate 31 with bolts and an upper heat shield plate piece 61 fixed to the support plate 31 form a substantially trapezoidal shape.

As shown in FIGS. 13 and 14, the left and right heat shield plate pieces 60 have mounting portions 60a provided at the top thereof attached to the left and right pedestals 31a fixed to the support plate 31 with bolts, and mounting portions provided at the bottom thereof. 60b is attached to left and right cover attachment brackets 62 with bolts, and the left and right cover attachment brackets 62 are attached to the lower portion of the attachment plate 14 of the DPF case 16 with bolts. Further, the left and right pedestals 31a fixed to the support plate 31 are extended rearward, and the extension portions 31b are provided with anti-vibration rubbers 63 connected to the upper portion of the column frame 38 of the control section.

Further, the outer peripheral side of the heat shield provided between the rear portion of the bonnet 23 and the column frame 38 of the control section is covered with a spacer cover 37 provided behind the bonnet 23 and having a slightly wide front-to-rear width. In this case, four angle-shaped metal fittings (not shown) are fixed to the inner front side of the spacer cover 37 which is formed by bending a steel plate into a substantially inverted U shape.

On the other hand, the left and right pedestals 31a fixed to the support plate 31 are provided with elongated holes, and upper metal fittings 64 are attached with four bolts b1 so as to be positionally adjustable in the front-rear direction. Also, the lower metal fittings 65 are attached to the right and left cover attachment brackets 62 with bolts so that the positions thereof can be freely adjusted in the front-rear direction. Then, the front surfaces of the metal fittings fixed to the spacer cover 37 are overlapped with the front surfaces of the upper metal fittings 64 and the lower metal fittings 65, and the front side of the spacer cover 37 is attached with four bolts b2. Also, the lower part of the spacer cover 37 is brought into contact with the outer surfaces of the left and right lower metal fittings 65 and attached with two bolts b2.

Heat exhaust holes 37c and 37d are provided in the top plate portion 37a facing the DPF case 16 and the left and right side plate portions 37b of the spacer cover 37. configured to exhaust air from More specifically, the top plate portion 37a of the spacer cover 37 is provided with eight heat exhaust holes 37c which are elongated slit-like holes whose longitudinal direction is the horizontal direction. Further, each of the left and right side plate portions 37b of the spacer cover 37 is provided with seven heat exhaust holes 37d which are elongated in a slit-like manner and whose longitudinal direction is obliquely upward and rearward.

Seals 66 and 67 made of weather strips are attached to the front and rear ends of the spacer cover 37, and the front and rear ends of the bonnet 23 and the front end of the control section are opened and closed by the front and rear seals 66 and 67. (Column frame 38) is closed and eliminated. Furthermore, a cap 68 closes the hole in the top plate portion 37a of the spacer cover 37 which is drilled so that the four bolts b1 for attaching the upper metal fitting 64 to the support plate 31 can be removed.

The support plate 31 that supports the rear portion of the bonnet 23 is formed with a descending inclined surface 31b facing rearward at an intermediate portion from the upper portion where the rear plate 30b of the hinge 30 is attached to the lower portion where the attachment plate 14 of the DPF case 16 is attached. The rear part of the DPF case 16 is covered from above. In addition, an upper heat shield plate piece 61 extending rearward and upward is fixed in the middle of the downward inclined surface 31 b of the support plate 31 . Further, the left and right end sides of the upper heat shield plate piece 61 are covered with the pedestal 31a of the support plate 31. As shown in FIG.

Accordingly, rainwater or car wash water that enters from the heat exhaust holes 37c provided in the top plate portion 37a of the spacer cover 37 falls from the top of the support plate 31 to the downward slope 31b, and finally reaches the slope 31b of the support plate 31. and the upper heat shield plate piece 61 , which is substantially V-shaped in side view (storage portion) 69 . In addition, a hole is bored near the bottom of the upper heat shield plate piece 61 in the center in the left-right direction (at the bottom of the reservoir 69), and the starting end of the drain hose 70 is inserted into this hole from behind through the grommet 71 to the reservoir. 69 with instant glue.

Further, the end portion of the drain hose 70 is led from the rear of the mounting plate 14 to the left rear side of the engine 2 while appropriately selecting the piping position by the mounting band, and finally the rainwater accumulated in the reservoir 69 is directed to the ground. Configure to drain. A fixed cover 71 which is attached to the auxiliary equipment bracket 17 and rises up is attached to the left and right lower portions of the bonnet 23, and a front part thereof is attached to the auxiliary equipment bracket 17 in the vicinity of the radiator with a bolt with a knob 72. A side cover 72 is provided which is fixed by inserting a mounting hole provided at the rear end of the pin 62a.

Therefore, the cooling fan 73 of the engine 2 sucks the cooling air from the vent 24 of the bonnet 23, and the cooling air exchanges heat with the cooling water of the engine 2 at the core portion of the radiator 18 to become hot air. Exhaust air passes around the engine 2 provided inside the bonnet 23 and reaches a heat shield plate provided at the rear. Since the blocking plate blocks the flow of the exhaust air to the control section side, most of the exhaust air is discharged to the outside of the machine through the exhaust holes provided on the lower side of the engine 2 and the side cover 72 .

However, the pressure (atmospheric pressure) inside the bonnet 23 where the engine 2 is installed is high due to the exhaust air, and part of the exhaust air flows around the DPF case 16 provided above the rear part of the engine 2, and furthermore, the spacer cover 37 The heat is discharged to the outside of the machine through heat exhaust holes 37c and 37d provided in the top plate portion 37a and the left and right side plate portions 37b. Therefore, when the DPF case 16 generates heat as the DPF is regenerated, and the air surrounding the DPF case 16 is heated by the heat, the heated hot air passes through the exhaust heat holes 37c and 37d together with the exhaust air. It is possible to eliminate the risk of thermal damage to peripheral sensors and rubber parts due to being discharged to the outside.

The first embodiment relating to the heat damage countermeasure of the exhaust gas aftertreatment device for the engine 2, which is the feature of the present invention, has been described above. The tractor 1 according to the second covered embodiment will be described. As shown in FIGS. 15 to 18, in this tractor 1, a cabin 73 covers an operation section in which a driver's seat 33, a steering handle 39, and the like are provided. The cabin 73 is attached to the vehicle body while being supported by the front transmission case 3 and the rear axle case for vibration isolation.

The structure of covering the engine 2 and the DPF case 16 as an exhaust gas post-treatment device with the bonnet 23 is the same as that of the tractor 1 of the first embodiment. If the rear portion of the spacer cover 37 that covers the outer peripheral side of the plate is brought into close contact with the front surface of the cabin 73 and the top plate portion 37a is extended forward as it is, the bonnet 23 is also provided, so that the ceiling portion 23a of the bonnet 23 is also provided. A step is generated between the end portion and the front end portion of the top plate portion 37a of the spacer cover 37, and the gap created by this step can be used as a heat exhaust hole for hot air.

However, since there is a risk that rainwater or car wash water may enter the hood 23 through this step, the front end of the top plate 37a of the spacer cover 37 is closed, and the rear end of the ceiling 23a of the bonnet 23 is closed. It is inclined downward to reach the front surface of the cabin 73 . Therefore, even if the height of the bonnet 23 near the rear is increased by providing the exhaust gas post-treatment device above the rear portion of the engine 2 and a step is generated between the spacer cover 37 and the spacer cover 37, the step is removed by the spacer cover 37. By slanting the top plate portion 37a toward the rear, it can be eliminated, and by changing the shape of the spacer cover 37, the appearance is changed to improve the appearance.

In addition, since the top plate portion 37a of the spacer cover 37 is inclined downward, hot air can easily escape rearward from the heat exhaust hole 37c, and the swing fulcrum position of the wiper 75 provided on the front window 74 of the cabin 73 is lowered. Therefore, a large wiper 75 can be attached to secure the forward visibility of the driver.

Furthermore, the weather strip 67 attached to the rear end of the spacer cover 37 must match the shape of the spacer cover 37, which is the base of the weather strip 67, with the column frame 38 so that it is in close contact with the portal frame of the column frame 38 of the control section. There are restrictions that must be However, this time, the weather strip 67 attached to the rear end of the spacer cover 37 is changed so that it is in close contact with the glass surface of the front window 74 of the cabin 73, so the shape of the spacer cover 37 can be changed without changing the shape of the column frame 38. can decide.

Further, since the top plate portion 37a of the spacer cover 37 is inclined downward and closely contacts the glass surface of the front window 74 of the cabin 73 via the weather strip 67, the top plate portion 37a of the spacer cover 37 is closer to the rear end. , and the front surface of the control section serve as a drainage channel for rainwater to flow left and right, thereby reducing rainwater intrusion into the heat exhaust hole 37c.

As shown in FIG. 19, a fuel filter 77 and a fuel filter 77 are provided in the engine fuel supply path for supplying the engine 2 with light oil stored in left and right fuel tanks 76 provided below the control unit. A separate water separator 78 is provided. These fuel filter 77 and water separator 78 are attached via brackets to the frame of the steering section behind the right front wheel 8 so that the fuel filter can be easily replaced and drained. A cover 79 covers them.

However, there is a risk that mud adhering to the right front wheel 8 will accumulate on the upper surface of the cover 79 as the vehicle is being driven. It is inclined downward to make it easier for mud accumulated during car washing to slide down from the upper surface 79a to the front surface 79b onto the ground. Also, as shown in FIG. 3, a cover 80 is provided between the DPF case 16 and the upper part of the engine 2 to block hot air from the DPF case 16, or is provided near the left side of the DPF case 16 as shown in FIG. A cover 81 covering an exhaust elbow or the like is provided to prevent a worker from being burned by touching a high-temperature part with the cover 81 when the bonnet 23 is opened.

Furthermore, if the cap 68 provided on the top plate portion 37a of the spacer cover 37 is removed and the four bolts b1 are removed, or if the bonnet 23 is opened and the bolts b2 attached to the front and outer surfaces of the lower metal fittings 65 are removed, the spacer cover 37 can be removed. In this state, the bonnet 23 can be removed by removing the bolts that attach the rear plate 30b of the hinge 30 to the support plate 31 and removing the gas spring 32 that is attached to the ceiling 23a of the hood 23. Therefore, when the hood 23 is removed in this way, replacement of the new DPF 16 and maintenance of the engine 2 are facilitated.

Although the embodiments of the present invention have been described above, the heat damage countermeasures of the exhaust gas aftertreatment device, which are the features of the present invention, are summarized here. , and a control section including a steering handle 39 and a driver's seat 33 are separated by a heat shield plate, and the outer peripheral side of the heat shield plate is covered with a spacer cover 37. - 特許庁The exhaust gas aftertreatment device 16 provided above the rear portion of the engine 2 is covered by the rear portion of the bonnet 2 and the front side of the spacer cover 37 in front of the heat shield plate, and the spacer faces the exhaust gas aftertreatment device 16. Heat exhaust holes 37c and 37d are provided in the top plate portion 37a and the side plate portion 37b of the cover 37 so that hot air heated by the exhaust gas aftertreatment device 16 is exhausted outside the machine through the heat exhaust holes 37c and 37d. Configure.

Therefore, the hot air heated by the heat generated by the exhaust gas aftertreatment device 16 provided above the rear part of the engine 2 is carried on the exhaust air flowing backward by the cooling fan 73 of the engine 2, and the control part behind it. The heat exhaust holes 37c and 37d provided in the top plate portion 37a and the side plate portion 37b of the spacer cover 37 in front of the partitioning heat shield plate can quickly exhaust heat to the outside of the machine. It is possible to prevent heat damage to the peripheral parts of the gas post-treatment device 16 and the like.

The exhaust heat holes 37c and 37d for exhausting hot air to the outside of the machine are formed by a top plate portion 37a facing the exhaust gas aftertreatment device 16 of a spacer cover 37 covering the outer peripheral side of a heat shield plate separating the bonnet 2 and the control section. Since the spacer cover 37 is provided on the side plate portion 37b, even if the strength of the spacer cover 37 is deteriorated by providing the heat exhaust holes 37c and 37d, the spacer cover 37 hides the heat shield plate and the like to improve the appearance. It plays the role of a decorative cover, and since its strength is not so important in the first place, there is no need to reinforce it with a reinforcing material. Furthermore, for safety reasons, if the heat exhaust holes 37c and 37d are formed by a plurality of slit-like elongated holes that are not accessible to hands, the spacer cover 37 can be changed and the appearance can be improved.

In the tractor 1, a mounting plate 14 for the exhaust gas aftertreatment device 16 is erected on the rear part of the engine 2, and a support plate 31 for mounting the rear part of the bonnet 2 is mounted on the mounting plate 14. The upper portion of the gas post-treatment device 16 near the rear is covered to prevent rain water entering from the heat exhaust hole 37c of the spacer cover 37 from falling on the exhaust gas post-treatment device 16.例文帳に追加

That is, the exhaust gas aftertreatment device 16 provided above the rear portion of the engine 2 is covered by the rear portion portion of the bonnet 23 and the front portion portion of the spacer cover 37 in front of the heat shield plate. Since the exhaust heat hole 37c provided in the exhaust gas post-treatment device 16 faces upward near the rear portion of the exhaust gas post-treatment device 16, the rainwater entering the heat exhaust hole 37c provided in the top plate portion 37a of the spacer cover 37 Drop down towards the rear.

However, since the upper part of the exhaust gas aftertreatment device 16 near the rear is covered with the support plate 31 for attaching the rear part of the bonnet 23, it is possible to prevent rainwater from falling on the exhaust gas aftertreatment device 16. It does not affect the regeneration of the air or deteriorate the forward visibility due to the generation of water vapor. Moreover, the support plate 31 of the bonnet 23 can prevent rainwater from falling on the exhaust gas aftertreatment device 16, which is convenient because there is no need to provide a new cover for preventing rainwater from falling.

Further, the tractor 1 is provided with heat shield plate pieces 60 and 61 on the mounting plate 14 of the exhaust gas aftertreatment device 16 and the support plate 31 for mounting the rear portion of the bonnet 23, and serves as a heat shield plate separating the bonnet 23 and the control section. In addition, an upper heat shield plate piece 61 directed rearward and upward is provided on the downward inclined surface 31b directed toward the rear of the support plate 31 to which the rear part of the bonnet 23 is attached, and the inclined surface 31b of the support plate 31 and the upper heat shield plate piece are provided. A substantially V-shaped space in a side view formed by 61 is configured as a storage portion 69 for rainwater entering from the heat exhaust hole 37c of the spacer cover 37. As shown in FIG.

Therefore, a heat shield plate that covers the substantially trapezoidal rear surface of the bonnet 23 without gaps, a mounting plate 14 that is provided for mounting the exhaust aftertreatment device 16 on the rear part of the engine 2, and a rear part of the bonnet 23 that is attached to the engine 2 The material cost can be reduced by filling the remaining gaps with the heat shield plate pieces 60 and 61 while utilizing each plate surface of the support plate 31 provided for attachment.

In addition, rainwater that has fallen on the support plate 31 that attaches the rear part of the bonnet 23 and has penetrated through the heat exhaust holes 37c of the spacer cover 37 can fall on, for example, sensors that are not waterproofed using the support plate 31 as a guide member. A storage part 69 for storing rainwater falling on the support plate 31 is provided so as not to cause trouble. The storage portion 69 is formed by the inclined surface 31b of the support plate 31 and the upper heat shield plate piece 61 by providing the upper heat shield plate piece 61 facing rearward and upward on the downward inclined surface 31b facing the rear of the support plate 31. A substantially V-shaped space in a side view can be configured in the rainwater reservoir 69 .

The tractor 1 is provided with a drain hose 70 at the bottom of the rainwater reservoir 69 so that the rainwater accumulated in the reservoir 69 is guided to the ground and drained by the drain hose 70 . Therefore, the drain hose 70 can be used to guide the rainwater to the ground and drain it before the rainwater overflows from the reservoir 69, preventing the rainwater and car wash water from accumulating in the surrounding parts and causing them to rust. can be prevented. The drain hose 70 is provided near the lower portion of the upper heat shield plate piece 61 to catch water flowing backward during forward traveling and facilitate drainage. Furthermore, since the drain hose 70 is attached by the grommet 71, it is not necessary to weld the iron pipe connecting the drain hose 70 to the upper heat shield plate piece 61, thereby reducing the cost.

In addition, the tractor 1 is provided with seals 66 and 67 at the front and rear ends of the spacer cover 37 which is formed in a substantially inverted U shape by the top plate portion 37a and the side plate portion 37b provided with the heat exhaust holes 37c and 37d. The front and rear seals 66, 67 eliminate gaps between the rear end of the bonnet 23 and the front end of the control section. For this reason, the seal 66 provided at the front end of the spacer cover 37 eliminates the gap provided to prevent shock absorption accompanying the opening and closing of the bonnet 23, and the seal 67 provided at the rear end of the spacer cover 37 prevents vibration with the control section. A gap based on the difference can be eliminated, and by closing such a gap with the seals 66, 67, it is possible to prevent rainwater from entering the bonnet 23 through other than the heat exhaust holes 37c, 37d.

In addition, the tractor 1 is provided with the top plate portion 37a of the spacer cover 37 inclined downward toward the rear. Therefore, if the exhaust gas aftertreatment device 16 is provided above the rear part of the engine 2, the height of the bonnet 23 near the rear part is increased, and even if there is a step between the bonnet 23 and the spacer cover 37, the step is removed by the spacer cover 37. can be eliminated by slanting the top plate portion 37a of the spacer cover 37 downward toward the rear, and the rear end of the top plate portion 37a of the spacer cover 37 and the front surface of the control unit serve as a drainage channel for flowing rainwater left and right , and rainwater entering the heat exhaust hole 37c can be reduced.

1 tractor (work vehicle)
2 diesel engine 14 mounting plate 16 DPF case (exhaust gas aftertreatment device)
23 Bonnet 31 Support Plate 33 Driver's Seat 37 Spacer Cover 37c Heat Exhaust Hole 37d Heat Exhaust Hole 39 Steering Handle 60 Heat Insulation Plate Piece 61 Heat Insulation Plate Piece 69 Reservoir 79 Drain Hose

Claims (6)

A work vehicle in which a bonnet covering an engine and an exhaust gas aftertreatment device and a control section including a steering handle and a driver's seat are separated by a heat shield plate, and the outer peripheral side of the heat shield plate is covered by a spacer cover, the rear side of the engine. The exhaust gas aftertreatment device provided above is covered by the rear side of the bonnet and the front side of the spacer cover in front of the heat shield plate, and heat is discharged to the top plate and side plate portions of the spacer cover facing this exhaust gas aftertreatment device. 1. A work vehicle characterized by comprising a hole for exhausting hot air heated by the exhaust gas aftertreatment device to the outside of the machine through the heat exhaust hole. A mounting plate for the exhaust gas aftertreatment device is erected on the rear part of the engine, and a support plate for mounting the rear part of the bonnet is attached to the mounting plate, the support plate covering the upper part of the exhaust gas aftertreatment device near the rear, 2. The work vehicle according to claim 1, wherein the exhaust gas post-treatment device is prevented from rainwater entering through the heat exhaust hole of the spacer cover. A heat shield plate piece is provided on the mounting plate of the exhaust gas aftertreatment device and the support plate for mounting the rear portion of the bonnet to form a heat shield plate for partitioning the bonnet and the control section, and the support plate for mounting the rear portion of the bonnet. An upper heat shield plate piece extending rearward and upward is provided on the downward inclined surface toward the rear, and a substantially V-shaped space in a side view formed by the inclined surface of the supporting plate and the upper heat shield plate piece is removed from the spacer cover. 3. The working vehicle according to claim 2, wherein the rainwater intruding through the heat hole is formed in a reservoir. 4. The work vehicle according to claim 3, wherein a drain hose is provided at the bottom of said rainwater reservoir, and rainwater accumulated in said reservoir is guided to the ground by said drain hose and drained. Seals are provided at the front and rear ends of the spacer cover, which is formed in a substantially inverted U shape by the top plate portion and the side plate portions provided with the heat exhaust holes, and the rear end portion of the bonnet and the front end of the control section are provided by the front and rear seals. 5. The work vehicle according to any one of claims 1 to 4, wherein a gap generated between the parts is eliminated. The work vehicle according to any one of claims 1 to 5, wherein the top plate portion of the spacer cover is inclined downward toward the rear.

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