JP5948894B2 - Work vehicle - Google Patents

Description

  The present invention relates to an exhaust gas treatment apparatus such as a work vehicle, particularly a tractor, to which work machines for agriculture, construction, transportation and the like are connected.

  In large vehicles such as trucks, nitrogen oxide (hereinafter referred to as NOx) emission regulations are a problem, but in the agricultural field, exhaust gas regulations are expected to strengthen NOx regulations. It has become a situation that must consider the mounting position of. A working vehicle such as a tractor, a riding lawn mower, or a combiner is provided with an exhaust device that purifies the exhaust gas of the engine in a reducing atmosphere. and so on.

In Patent Document 1 below, in order to efficiently purify and reduce NOx in the exhaust gas, a reducing agent injection device for injecting a reducing agent such as urea water into the exhaust gas is provided, and a dispersant that further promotes evaporation of the urea water is provided. The provided arrangement is disclosed.
Patent Document 2 below discloses a combine in which a diesel engine is disposed in the vicinity of a step and an exhaust gas purifying device is provided on the lower surface of the step.

JP 2011-236746 A JP 2010-83331 A

  In the reducing agent injection device described in Patent Document 1, exhaust gas can be purified by generating uniform ammonia in the exhaust passage. However, when an exhaust purification device is provided in a work vehicle for farm work, an installation space for that purpose is required. This leads to an increase in the size of the work vehicle itself.

  In the configuration described in Patent Document 2, an exhaust gas purifying device is provided on the lower surface of the step, thereby effectively utilizing the space on the lower surface side of the step. A large work vehicle such as a combine often has a space on the lower surface of the step, but a relatively small work vehicle such as a tractor or a lawn mower may not have such a space. In addition, since the airframe tilts when there are irregularities in the field, it is also necessary to firmly support the exhaust purification device on the airframe.

  An object of the present invention is to provide a work vehicle having a compact configuration that is firmly supported by the airframe and devised the layout of the exhaust emission control device.

The above-described problems of the present invention are solved by the following solution means.
According to the first aspect of the present invention, an engine (E) having a cylinder block (7) at a lower portion and a cylinder head (6) at an upper portion, a pair of left and right traveling devices (17, 18), and the left and right traveling devices (17 , 18), a transmission case (16) having a transmission (15) provided therein for shifting the rotational power of the engine (E) and transmitting it to the traveling devices (17, 18), and the engine An SCR device (38) including a tank (38b) for storing a catalyst for purifying exhaust gas generated from (E) and an injection device (38a) for injecting the catalyst in the tank (38b) into the exhaust gas; A pipe (39) provided on one of the left and right sides of the machine body for discharging the exhaust gas purified by the SCR device (38), and a bracket (on the side of the cylinder block (7) on the pipe (39) side) 53 When a mounting bracket (50) disposed on a side surface of the pipe (39) side of said transmission case (16), said mounting bracket (50) and bracket (53) intermediate bracket (55) which is provided between the And a fixing means (57) for fixing the mounting bracket (50), the bracket (53), and the intermediate bracket (55), and the tank (38b) of the SCR device (38) is provided in the mounting bracket (50). The work vehicle is configured to support the tank (38b) of the SCR device (38) by the bracket (53) and the mount bracket (50).

According to a second aspect of the invention, the intermediate bracket (55) is a working vehicle according to claim 1, wherein the vibration damping material that absorbs vibration of the work vehicle.

  According to the first aspect of the present invention, the urea aqueous solution tank (38b) is supported by the cylinder block (7) of the engine (E) having high strength via the bracket (53), so that the urea aqueous solution tank (38b) is provided. It is stably fixed to the aircraft. A mounting bracket (50) is also provided on the side surface of the transmission case (16) on the pipe (39) side that discharges exhaust gas, and the urea aqueous solution tank (38b) is supported by the bracket (53) and the mounting bracket (50). The urea aqueous solution tank (38b) can be firmly supported by attaching the side surface of the mission case (16) and the side surface of the cylinder block (7). Further, since the urea aqueous solution tank (38b) is on the same side as the pipe (39), the length from the engine (E) to the pipe (39) is shortened, and a compact configuration is obtained.

Further , by fixing the intermediate bracket (55) between the mounting bracket (50) and the bracket (53) by the fixing means (57), and providing the urea aqueous solution tank (38b) on the mounting bracket (50), The support structure of the urea aqueous solution tank (38b) becomes even stronger. Therefore, the urea aqueous solution tank (38b) can be stably supported more firmly on the work vehicle (1).

According to the second aspect of the invention, in addition to the effect of the first aspect of the invention, the intermediate bracket (55) serves as a vibration isolating material and absorbs vibrations during work and travel, thereby In addition, workability is improved because it does not cause discomfort.

It is a left view of the work vehicle of the Example of this invention. It is a front view of the tractor of FIG. It is a front view at the time of removing the bonnet of FIG. It is a right view of the engine vicinity. FIG. 5 is a perspective view of the vicinity of the mount bracket of FIG. 4. It is a top view of the vicinity of the cockpit of the tractor of FIG. It is a perspective view of the engine vicinity of the tractor of FIG. FIG. 2 is a side view of the vicinity of the engine when the position of the urea aqueous solution tank of the tractor in FIG. 1 is changed (reference example). FIG. 9A is a right side view of the vicinity of the engine of FIG. 8 (reference example), and FIG. 9B is a perspective view of the bracket of FIG. 9A. FIG. 10 is a rear view of FIG. 9A (reference example). It is a top view of Fig.9 (a) (reference example). It is a top view at the time of changing arrangement | positioning of the DPF apparatus of the tractor of FIG. It is a perspective view (simplified figure) at the time of seeing the tractor carrying a DOC device from the left front. It is a top view of a tractor carrying a DOC device (reference example). It is a top view at the time of changing the position of the urea aqueous solution tank of the tractor of FIG. It is a top view of a tractor carrying a DOC device. It is a control block diagram of the tractor of this embodiment. It is a side view of the engine vicinity at the time of changing arrangement | positioning of a DPF apparatus. FIG. 19A is a side view of the vicinity of the engine when the arrangement of the DPF device is changed, and FIG. 19B is a view of the cross section of the DPF portion of FIG. It is a side view of the engine vicinity at the time of changing arrangement | positioning of a DPF apparatus. FIG. 21A is a side view of the vicinity of the engine when the arrangement of the DPF device is changed, and FIG. 21B is a plan view of FIG.

  Embodiments of the present invention will be described below with reference to the drawings. In the present specification, left and right are respectively referred to as left and right in the forward direction of the vehicle, and front and rear are referred to as front and rear, respectively. Here, the left and right traveling axles in the present specification refer to traveling axles in the left and right direction facing the traveling direction of the work vehicle. And according to embodiment of this invention, it demonstrates below by taking as an example the tractor which is an example of a working vehicle.

  FIG. 1 shows a left side view of a tractor 1 according to an embodiment of the present invention, and FIG. 2 shows a front view (right side portion) of the tractor of FIG. 3 shows a front view when the hood 26 of FIG. 2 is removed, and FIG. 4 shows a right side view in the vicinity of the engine E. 5 shows a perspective view of the vicinity of the mounting bracket of FIG. 4, and FIG. 6 shows a top view of the vicinity of the cockpit of the tractor 1 of FIG.

  The tractor 1 has an engine E mounted in a hood 26 at the front of the airframe, transmits the rotational power of the engine E to a transmission 15 (transmission) in the transmission case 16, and travels rotational power decelerated by the transmission 15. The information is transmitted to the front wheel 17 and the rear wheel 18 which are devices. The periphery of the cockpit 22 on the fuselage is covered with a cabin 19, and an operator gets on and off the tractor 1 from step 10 provided on both the front left and right sides of the cabin 19.

  A steering handle 20 is erected from the dashboard 13 provided with a meter panel 117 in front of the cockpit 22 inside the cabin 19, and a forward / reverse lever 120 for switching between forward and backward movement of the tractor 1 is disposed on the left side thereof (FIG. 6). ), A parking brake 122, a PTO change lever 124 (changeable to 2nd speed-N (neutral) -1st speed), and the like. The PTO shift lever 124 determines the PTO shift, and the PTO on / off switch (PTO clutch on / off switch) 126 rotates and stops the PTO shaft (not shown).

  The engine E is a diesel engine including a turbocharger 3 that pressurizes intake air into a cylinder, and includes a cylinder block 7 (FIG. 8) with a cylinder head 6 (FIG. 8) fastened on an upper surface. Further, a cooling fan 27 (FIG. 4) for air cooling of the engine E is arranged. As shown in FIG. 4, the turbocharger 3 is attached to the cylinder head 6. A hitch 21 and a three-point link (not shown) are provided between the left and right rear wheels 18 and 18 so that a working machine such as a rotary is mounted.

  An exhaust device is connected to the engine E. The exhaust device is configured by providing an exhaust purification device 35 in an exhaust pipe 41 connected to an exhaust manifold 33 (FIG. 8) of the engine E.

  The exhaust purification device 35 includes a DPF (Diesel Particulate Filter) device 36, an SCR (Selective Catalytic Reduction) device 38, and the like. DPF is a device (filter) that reduces particulate matter (hereinafter referred to as PM) contained in diesel engine exhaust gas. SCR is a selective reduction NOx catalyst that purifies nitrogen oxides in exhaust gas. is there.

  The SCR device 38 includes a urea aqueous solution injection device (for example, an injector) 38a for urea aqueous solution serving as a catalyst, and a tank 38b for storing the urea aqueous solution supplied to the urea aqueous solution injection device 38a. The catalyst is not limited to urea.

  Exhaust gas discharged from each cylinder of the engine E to the exhaust manifold 33 is sent to the DPF device 36 via the first exhaust pipe 41. After PM is collected by the DPF device 36, the exhaust gas is sent to the SCR device 38 through the second exhaust pipe 42. The exhaust gas from which nitrogen oxides have been rendered harmless by the SCR device 38 is discharged upward of the tractor 1 by the tail pipe 39 on the right side of the mission case 16.

  The urea aqueous solution tank 38b of the SCR device 38 is supported by a bracket 53 attached to the vehicle body frame 8 on the side of the cylinder block 7 of the engine E. As shown in FIG. 7, the lower part of the cylinder block 7 of the engine E is inserted between the left and right body frames 8, 8, and the bracket 53 is a cylinder (an example of a fixing means) penetrating through the body frame 8. It is fixed to the block 7.

  By supporting the urea aqueous solution tank 38b by the bracket 53 provided on the right side surface of the cylinder block 7, that is, the cylinder block 7 has high strength. When the urea aqueous solution tank 38b is attached to this portion by a fixing means such as a bolt 57, The urea aqueous solution tank 38b is stably fixed to the tractor 1.

  Further, the mounting bracket 50 is connected to the right side surface of the transmission case 16 so that the urea aqueous solution tank 38b is also supported by the mounting bracket 50. A tail pipe 39 is located on the right side surface of the mission case 16, and the urea aqueous solution tank 38b is disposed on the tail pipe 39 side, so that the exhaust gas piping from the engine E is shortened.

  In relatively small work vehicles such as tractors and lawn mowers, there are cases where there is no space, and when a new member (such as a urea aqueous solution tank) is newly mounted, there is no place, so some contrivance is required. In this embodiment, the urea aqueous solution tank 38b is attached from the cylinder block 7 and the transmission case 16 via the bracket 53, the mount bracket 50, and the like. This configuration is safe because the urea aqueous solution tank 38b can be firmly supported even if the aircraft is tilted due to unevenness in the field or the like.

  The mount bracket 50 has a stepped shape (a shape bent in a Z shape) in a side view, the urea aqueous solution tank 38b is placed on the plane of the lower step 50a, and the mounting stay 40 is attached from the urea aqueous solution tank 38b along the vertical surface 50b. It is good to put out and install.

  Alternatively, the mounting bracket 50 may not be directly provided with the urea aqueous solution tank 38b, but the mounting bracket 50 may be provided with an auxiliary bracket (not shown), and the urea aqueous solution tank 38b may be provided on the auxiliary bracket.

Since it may be difficult to directly provide the urea aqueous solution tank 38b on the mount bracket 50 depending on the size, type, and layout of the device mounted on the tractor 1, providing the auxiliary bracket provides a versatile and reliable urea aqueous solution. The tank 38b can be fixed.
Moreover, it can support firmly because a bracket becomes a double structure.

  The mount bracket 50 may be attached to the bracket 53 via an intermediate bracket 55 serving as a spacer. By sandwiching the intermediate bracket 55 between the mount bracket 50 and the bracket 53 and fixing with a fixing means such as a bolt 57, the mount bracket 50 can be firmly fixed and supported on the bracket 53. Therefore, the urea aqueous solution tank 38b can be stably supported by the tractor 1 and can be supported more firmly.

Further, by devising the material and shape of the intermediate bracket 55, the intermediate bracket 55 functions as a vibration isolator. The anti-vibration material absorbs vibrations of the equipment and device to be operated, and an elastic material such as natural rubber, silicon, urethane, or synthetic rubber may be used as a material or a sponge material.
Since the intermediate bracket 55 also serves as a vibration isolating material, the vibration during the operation of the tractor 1 and the traveling is absorbed and the operator is not uncomfortable, so that the workability is improved.

  As shown in FIG. 3, when the urea aqueous solution tank 38b is provided on the lower surface of the tail pipe 39 and the urea aqueous solution injector 38a is provided on the upper surface of the urea aqueous solution tank 38b, the injector 38a can be disposed so as to face the tail pipe 39. . The injector 38a may be a side surface instead of the upper surface of the urea aqueous solution tank 38b.

By arranging the tail pipe 39 and the urea aqueous solution tank 38b close to each other and injecting the urea aqueous solution into the tail pipe 39 from the injector 38a provided in the urea aqueous solution tank 38b, the distance from the urea aqueous solution tank 38b to the injection position is short. It becomes a compact configuration. Further, it is not necessary to provide a urea aqueous solution piping from the urea aqueous solution tank 38b, the cost is reduced, and there is no problem such as leakage of the urea aqueous solution from the connection portion of the piping.
In this embodiment, an example in which the urea aqueous solution tank 38b is provided on the right side of the aircraft is shown. However, when the tail pipe 39 is on the left side of the aircraft, the urea aqueous solution tank 38b may be provided on the left side as well.

FIG. 8 is a left side view of the front portion when the position of the urea aqueous solution tank 38b of the tractor in FIG. 1 is changed. In the following description, when the position of the urea aqueous solution tank 38b is not on the side of the cylinder block 7 and the transmission case 16 of the engine E, a reference example is given.
9A is a right side view of the vicinity of the engine E in FIG. 8, FIG. 9B is an enlarged view (perspective view) of the bracket 58 in FIG. 9A, and FIG. Is a rear view of FIG.

  As a reference example, a bracket 58 may be provided at the rear portion of the cylinder block 7 of the engine E, and the urea aqueous solution tank 38 b may be supported by the bracket 58. Any shape may be used as long as the urea aqueous solution tank 38b can be supported.

  Since the cylinder block 7 has high strength, if a stay (not shown) is extended rearward from this portion and the urea aqueous solution tank 38b is attached with fixing means such as a bolt, the urea aqueous solution tank 38b is stably fixed to the tractor 1. The Since there is a space between the engine E and the cabin 19 of the tractor 1, the urea aqueous solution tank 38b can be compactly arranged by using this space.

  Also, as shown in FIG. 9B, the bracket 58 is provided with a mounting hole 58a for the cylinder block 7 and a mounting hole 58b for the transmission case 16, and the bracket 58 is attached to the cylinder block 7 and the transmission case 16 to If the urea aqueous solution tank 38b is provided behind the block 7 and on the upper surface of the mission case 16, the periphery of the urea aqueous solution tank 38b is surrounded by the structure, so that it is more stably fixed to the tractor 1.

FIG. 11 shows a plan view (partially added view) of FIG.
Since the tail pipe 39 is on the right side of the mission case 16, in this case, the injector 38a for blowing the urea aqueous solution into the tail pipe 39 cannot be directly provided in the urea aqueous solution tank 38b. Therefore, the urea aqueous solution injection line (which may be a tube, a tube, etc.) 52 is connected to the urea aqueous solution tank 38b, and the urea aqueous solution in the urea aqueous solution injection line 52 may be injected into the tail pipe 39 by the injector 38a.

  FIG. 12 shows a plan view when the arrangement of the DPF device 36 of the tractor 1 of FIG. 11 is changed. Exhaust gas discharged from each cylinder of the engine E to the exhaust manifold 33 is sent to the DPF device 36 via the first exhaust pipe 41. Usually, the DPF device 36 is provided straight along the left-right center line C of the machine body, and the length of the first exhaust pipe 41 is adjusted to connect the pipe to the DPF device 36.

  If the length of the first exhaust pipe 41 is long, the flow path of the exhaust gas becomes long and a curve (curved part) is formed, so that resistance of the gas flow occurs, making it difficult for the exhaust gas to flow or clogging. End up.

  Therefore, the DPF device 36 may be disposed obliquely with respect to the left-right center line C so that the distance between the outlet of the exhaust manifold 33 and the inlet of the DPF device 36 is shortened. In the example of FIG. 12, since there is an exhaust gas inlet at the rear part of the DPF device 36, the rear part is inclined toward the exhaust manifold 33 side (left side in the illustrated example). If the exhaust manifold 33 is on the left side of the fuselage and the exhaust gas inlet is on the left side of the DPF device 36 as shown in FIG. 11, the length of the first exhaust pipe 41 can be made relatively short. By tilting as shown in FIG. 12, the length of the first exhaust pipe 41 can be further shortened.

  By reducing the length of the first exhaust pipe 41 as much as possible, the exhaust gas discharged to the exhaust manifold 33 flows smoothly to the DPF device 36, so that the exhaust gas purification efficiency is also improved.

The above configuration is a case where the DPF device 36 and the SCR device 38 are provided as the exhaust purification device 35, but a DOC (Diesel Oxidation Catalyst) device 45 may be provided in addition thereto. DOC is an oxidation catalyst that removes hydrocarbons and carbon monoxide. DOC also has an oxidation performance of SOF (Solvable Organic Fraction). By providing the DOC device 45 in the upstream of the DPF device 36, HC is first oxidized to water and CO ₂ and CO is oxidized to CO ₂ by the catalytic action of the DOC. Also, of the NOx, NO is oxidized to NO _2. NO ₂ comes into contact with the PM deposited on the DPF and oxidizes (combusts) the PM. Further, the DOC device 45 may be provided before and after the SCR device 38.

  Note that it is not necessary to mount all of the DOC device 45, the DPF device 36, and the SCR device 38 on the tractor 1, and any combination may be used from the viewpoint of fuel consumption and cost as long as exhaust gas regulations are achieved.

  FIG. 13 shows a perspective view of the tractor 1 on which the DOC device 45 is mounted when viewed from the left front side (simplified view of only the front portion). The tractor 1 shown in this figure is equipped with a DOC device 45 and an SCR device 38, and no DPF device 36 is provided.

  Then, if the urea aqueous solution tank 38b is provided so that the upper surface of the urea aqueous solution tank 38b of the SCR device 38 is at the same height as the floor 48 (FIG. 1) of the cabin 19, the urea aqueous solution tank 38b does not interfere with the front of the aircraft. In addition, the field of view near the front wheel 17 is good, and it is easy to see the wrinkles of crops at the time of work, so the workability is excellent.

  The second exhaust pipe 42 connecting the DOC device 45 and the urea aqueous solution tank 38b of the SCR device 38 is formed of a flexible pipe (also referred to as a flexible hose or a flexible tube spiral pipe) that is flexible and can be bent freely. Also good. Even when the DOC device 45 and the SCR device 38 generate vibrations having different frequencies, such vibrations can be absorbed and the exhaust pipe can be prevented from being damaged due to stress.

  Further, when the tail pipe 39 is fixed to the front frame 19a by fixing means (not shown), a flexible joint (not shown) as described above is provided between the urea aqueous solution tank 38b of the SCR device 38 and the tail pipe 39. The tail pipe 39 can be fixed on the cabin 19 side, and the tail pipe 39 is stable and has a strong mounting structure and is resistant to vibration of the airframe.

  Further, the mount bracket 50 that supports the urea aqueous solution tank 38 b may be provided on the side surface of the mission case and in the lower front part of the cabin 19. Also in this case, it is possible to manufacture at low cost without the need to provide a special support member by attaching using the lower front part of the conventional cabin 19.

  When the urea aqueous solution tank 38b is provided at the lower front portion of the cabin 19, the front portion of the urea aqueous solution tank 38b is partially cut away to prevent interference with the front wheel 17 (indicated by a round frame X in FIG. 13). It is also good. By cutting out the front part of the urea aqueous solution tank 38b, a gap can be secured between the front wheel 17 and the front wheel 17 can be set large.

In FIG. 14, the top view of the tractor carrying the DOC apparatus 45 is shown. In this example, the urea aqueous solution tank 38b is provided behind the engine E (reference example).
The exhaust gas passes from the exhaust manifold 33 through the first exhaust pipe 41 and is sent to the DOC device 45 where hydrocarbons, carbon monoxide, SOF, and the like are removed. Further, the exhaust gas sent to the SCR device 38 through the second exhaust pipe 42 and detoxified with nitrogen oxides is discharged upward by the tail pipe 39 toward the tractor 1. The tail pipe 39 extends in the roof direction along the front frame 19 a of the cabin 19.
By adopting such a piping structure, the length of the exhaust pipe from the engine E until it is discharged into the atmosphere is shortened comprehensively, so that it can be manufactured at low cost.

FIG. 15 is a plan view when the position of the urea aqueous solution tank 38b is changed from FIG. As shown in FIG. 15, if the urea aqueous solution tank 38b is provided at a position away from the DOC device 45 and the turbocharger 3, the urea aqueous solution in the urea aqueous solution tank 38b can be prevented from becoming high temperature, and the urea aqueous solution tank 38b Can be installed at low cost.
The urea aqueous solution tank 38b may be positioned as shown in FIG. 13 as long as it is relatively far from the DOC device 45.

  Even if the tail pipe 39 is not connected to the urea aqueous solution tank 38b, the urea aqueous solution injection line 52 is connected to the urea aqueous solution tank 38b, and the urea aqueous solution in the urea aqueous solution injection line 52 is injected into the first exhaust pipe 41 by the injector 38a. It is good also as a structure sprayed on. In this case, the urea aqueous solution tank 38b can be easily detached from the airframe, the maintenance is excellent, and the urea aqueous solution injection position from the urea aqueous solution injection line 52 can be appropriately changed. The degree is improved.

Further, the urea aqueous solution may be injected not only in the upstream flow of the DOC device 45 but also in the downstream flow of the DOC device 45. In this case, the urea aqueous solution may be injected into the tail pipe 39 from the injector 38a provided in the urea aqueous solution tank 38b.
As shown in FIG. 16, when the urea aqueous solution tank 38b is provided behind the DOC device 45 (configuration in FIG. 14), the distance of the urea aqueous solution injection line 52 can be shortened.

  On the other hand, a working machine such as a rotary is mounted on the tractor 1, and power is transmitted from the engine E to the working machine by turning on and off the PTO clutch 28 (hydraulic clutch) by switching the PTO on / off switch 126. .

In FIG. 17, the control block diagram of the tractor 1 of this embodiment is shown.
If the urea aqueous solution in the urea aqueous solution tank 38b decreases, the processing ability of nitrogen oxides in the exhaust gas by the SCR device 38 is lowered, so it is not preferable to continue the operation.

  Therefore, a urea water sensor 54 that detects that the remaining amount of the urea aqueous solution in the urea aqueous solution tank 38b is small (for example, substantially zero) is provided in the urea aqueous solution tank 38b. When a signal from the urea water sensor 54 is input to the controller (control device) 100a of this machine, and the amount of liquid in the urea aqueous solution tank 38b is equal to or less than a predetermined amount, a signal is output to the controller 100b of the PTO. The current to the solenoid 56 of the PTO clutch 28 is cut off and the PTO clutch 28 is turned off. That is, the remaining amount of the urea aqueous solution in the urea aqueous solution tank 38b detected by the urea water sensor 54 and the disengagement operation of the PTO clutch 28 are linked. If the PTO clutch 28 is to be engaged, the entry is checked.

  If the PTO clutch 28 is disengaged, the operation cannot be continued until the urea aqueous solution is replenished, but the transmission from the engine E to the traveling system such as the front wheels 17 and the rear wheels 18 is continued, so that the movement is possible. .

  The engine speed (rpm) is detected by the engine speed sensor 60. The engine speed sensor 60 detects the rotation of the crankshaft of the engine E, and the position of the engine speed sensor 60 varies depending on the type of the engine E.

  Alternatively, a warning device 59 may be provided near the meter panel 117 of the tractor 1 to issue a warning to the worker. The warning device 59 may be activated simultaneously with the PTO clutch 28 being disengaged, or after the warning device 59 is activated, when the injection by the urea aqueous solution injection device 38a is continued (may be measured by a timer). ) The PTO clutch 28 may be disengaged. In the urea aqueous solution injection device 38a, the injection amount is controlled by a signal from the controller 100a. Since NOx basically changes depending on the relationship between the fuel injection amount and oxygen, the NOx value is calculated by monitoring the fuel amount and oxygen amount injected into the cylinder, and the amount of urea is controlled. Other methods may be used. Examples of the warning device 59 include a buzzer that emits sound, a visually recognizable lamp, and a monitor.

FIG. 18 shows a side view of the vicinity of the engine E when the arrangement of the DPF device 36 is changed.
A boss 70 for attachment is provided on the side surface of the cylinder block 7 of the engine E, and the DPF device 36 is attached using the boss 70. By providing the DPF device 36 in the cylinder block 7 having a high strength, the cylinder block 7 is stably fixed to the airframe and becomes a strong structure.
Since the DPF device 36 is heavy, a portion to which the DPF device 36 is attached vibrates with vibration of the airframe. For this reason, it attaches to the cylinder block 7 with strong intensity | strength.

  As shown in FIG. 18, the first exhaust pipe 41 on the exhaust introduction side of the DPF device 36 is disposed on the engine E and the exhaust manifold 33 side, and the second exhaust pipe 42 on the exhaust outlet side is disposed on the side portion of the engine E. Thus, the lengths of the first exhaust pipe 41 and the second exhaust pipe 42 can be shortened.

  In large trucks, etc., there is an engine E below the cabin 19, and an exhaust pipe extends from the engine E toward the rear of the fuselage, so a DPF device 36 is provided in the middle of the exhaust pipe (around the bottom of the loading platform). ing. However, since a small tractor has no space, the DPF device 36 is disposed in the engine room covered with the hood 26.

FIG. 19A shows a side view of the vicinity of the engine E (corresponding to the left side view of FIG. 4), and FIG. 19B shows a cross section of the DPF portion of FIG. The figure is shown.
When the DPF device 36 is provided on the upper rear side of the engine E, if the partition wall 72 is further provided between the partition wall 19b of the cabin 19 and the engine E, the heat of the DPF device 36 is hardly transmitted to the cabin 19 side. Therefore, heat can be prevented from being accumulated in the cabin 19 or the front glass of the cabin 19, and noise generated from the DPF device 36, the engine E, or the like is hardly transmitted, so that there is a soundproofing effect. With this configuration, the operator can work comfortably without feeling uncomfortable, thereby improving workability.
As shown in FIG. 19, hot air generated from the DPF device 36 and the engine E flows in the direction of arrow B in FIG. 19 by the fan 27, hits the partition wall 72, and then is discharged outside the tractor 1.

In addition, when the air guide plate 74 is provided under the partition wall 72, the hot air can be effectively discharged in the lateral direction (outward in the left-right direction) along the air guide plate 74, and the dust can be lifted up by heat and wind. Can be prevented. The air guide plate 74 is provided on the outer side of the DPF device 36 in the left-right direction so as to be left-right symmetrical so as to have a square shape in front view (rear view), so that the hot air is outward in the left-right direction of the DPF device 36 and downward. Flowing.
The upper part of the partition wall 72 is formed along the inner surface of the bonnet 26, and the wind guide plate 74 is provided at the lower part of the partition wall 72 so that the air can escape to the side net (FIG. 1), thereby effectively releasing heat. Can do.

FIG. 20 shows a side view of the vicinity of the engine E when the arrangement of the DPF device 36 is changed.
When the bracket 76 that connects the exhaust manifold 33 and the turbocharger 3 is provided, and the DPF device 36 that is directly attached to the turbocharger 3 is fixed by the bracket 76, the exhaust pressure loss can be reduced. Although the DPF device 36 becomes unstable due to the exhaust gas flow flowing through the DPF device 36, it is stably fixed and supported by fixing with the bracket 76, and there is no piping between the turbocharger 3 and the DPF device 36. Overall, exhaust pressure loss (pressure loss) is reduced. As the length of the exhaust pipe is shorter, the exhaust pressure loss is reduced and the decrease in engine horsepower is suppressed.

  The bracket 76 includes a vertical bracket 76 a that extends in the vertical direction on the upper surface of the exhaust manifold 33 and a connection bracket 76 b that supports the lower surface of the DPF device 36. If the elastic body 77 is provided between the vertical bracket 76a and the connecting bracket 76b, the vibration of the DPF device 36 can be absorbed. Since the DPF device 36 is heavier than a muffler or the like, it is necessary to suppress vibration of the attachment portion.

FIG. 21 (a) shows a side view of the vicinity of the engine E when the arrangement of the DPF device 36 is changed, and FIG. 21 (b) shows a plan view of FIG. 21 (a).
A bracket 78 having a rotation fulcrum 78 a of the bonnet 26 connected to the engine E is provided at the upper rear of the engine E, and the DPF device 36 is fixed to the bracket 78. By attaching using the bracket 78 having the rotation fulcrum 78a of the bonnet 26, another support member becomes unnecessary.

  The bracket 78 may be fixed to the engine E, and an elastic body 80 may be interposed between the bracket 78 and the DPF device 36. By providing the elastic body 80 between the bracket 78 and the DPF device 36, the vibration of the heavy DPF device 36 can be absorbed.

  The present invention can be used for a work vehicle equipped with an SCR device.

DESCRIPTION OF SYMBOLS 1 Tractor 3 Turbocharger 6 Cylinder head 7 Cylinder block 8 Body frame 10 Step 13 Dashboard 15 Transmission 16 Transmission case 17 Front wheel 18 Rear wheel 19 Cabin 20 Steering handle 22 Pilot seat 26 Bonnet 27 Cooling fan 28 PTO clutch 33 Exhaust manifold 35 Exhaust Purification device 36 DPF device 38 SCR device 39 Tail pipe 41 First exhaust pipe 42 Second exhaust pipe 45 DOC device 50 Mount bracket 52 Urea aqueous solution injection line 53 Bracket 54 Urea water sensor 55 Intermediate bracket 56 Solenoid 57 Bolt 58 Bracket 59 Warning device 60 Engine speed sensor 62 Common rail 64 Bracket 67 Mount 70 Boss 72 Bulkhead 74 Air guide plate 76 Bra Tsu DOO 77 elastic body 78 bracket 80 elastic body 82 plate 84 bracket 100 controller 117 meter panel 120 forward-reverse lever 122 parking brake 124 PTO shift lever 126 PTO switching on and off the switch 130 side-netting

Claims (2)

An engine (E) having a cylinder block (7) at the bottom and a cylinder head (6) at the top;
A pair of left and right traveling devices (17, 18);
A transmission case having a transmission (15) provided between the left and right traveling devices (17, 18) for shifting the rotational power of the engine (E) and transmitting it to the traveling devices (17, 18). (16) and
SCR device (38) comprising a tank (38b) for storing a catalyst for purifying exhaust gas generated from the engine (E) and an injection device (38a) for injecting the catalyst in the tank (38b) into the exhaust gas When,
A pipe (39) provided on one side of the left and right sides of the machine body for discharging the exhaust gas purified by the SCR device (38);
A bracket (53) fixed to the side surface of the cylinder block (7) on the pipe (39) side;
A mounting bracket (50) disposed on a side surface of the transmission case (16) on the pipe (39) side ;
An intermediate bracket (55) provided between the mounting bracket (50) and the bracket (53);
Fixing means (57) for fixing the mounting bracket (50), the bracket (53) and the intermediate bracket (55);
With
The tank (38b) of the SCR device (38) is provided on the mount bracket (50), and the tank (38b) of the SCR device (38) is supported by the bracket (53) and the mount bracket (50). A working vehicle characterized by The work vehicle according to claim 1, wherein the intermediate bracket (55) is a vibration isolating material that absorbs vibration of the work vehicle.

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