JP6470107B2 - Work vehicle - Google Patents

Description

  The present invention relates to a work vehicle such as a rice transplanter or a tractor that continuously performs seedling planting work.

  2. Description of the Related Art A conventional passenger rice transplanter is well known in which an engine is mounted between front and rear axles of a traveling machine body (see, for example, Patent Document 1). In this type of passenger rice transplanter, a fuel tank, an exhaust muffler, and an air cleaner are arranged around the engine. In the riding type rice transplanter disclosed in Patent Document 1, a fuel tank is disposed above the engine, and an air cleaner and an exhaust muffler are disposed on the rear side of the engine in such a manner as to be distributed to the left and right. The upper part of the engine, fuel tank, etc. is covered with a vehicle body cover. A control seat is arranged on the body cover. Therefore, an engine, a fuel tank, an exhaust muffler, and an air cleaner are located below the control seat. The left and right rear wheels that support the rear part of the traveling machine body are located on both the left and right sides behind the engine.

JP 2007-308118 A

  The external shape of the exhaust muffler employed in the riding type rice transplanter is generally a cylindrical shape or a rectangular parallelepiped shape. However, depending on the layout of the riding type rice transplanter, the exhaust muffler having a cylindrical shape or a rectangular parallelepiped shape cannot secure a sufficient capacity, and there is a problem that exhaust noise increases.

  This invention makes it a technical subject to provide the working vehicle which considered the above present conditions and improved.

  According to a first aspect of the present invention, in a work vehicle in which an engine and a transmission case are mounted between front and rear axles of a traveling machine body and a control seat is disposed on a vehicle body cover that covers the engine and the transmission case, the engine is sandwiched between the engine and the transmission case. An air cleaner is arranged on one side of the left and right, an exhaust muffler is arranged on the other side of the left and right, and the rear part of the pair of left and right horizontal frames that make up the traveling body is configured as an inclined part that increases in height toward the rear. The exhaust muffler is positioned between the intermediate frame connecting the transmission case and the rear axle case and the inclined portion of the horizontal frame, and the upper surface side of the exhaust muffler is aligned with the inclined portion of the horizontal frame. Is inclined.

  According to a second aspect of the present invention, in the work vehicle according to the first aspect, a suction fan for cooling the engine air is provided on one side of the left and right sides of the engine that is the air cleaner side.

  According to a third aspect of the present invention, in the work vehicle according to the second aspect of the present invention, an inter-stock transmission is located on one side of the left and right sides of the engine and below the air cleaner.

  According to the present invention, in a work vehicle in which an engine and a transmission case are mounted between front and rear axles of a traveling machine body and a control seat is disposed on a vehicle body cover that covers the engine and the transmission case, the engine is sandwiched between the left and right sides. An air cleaner is disposed on the side, an exhaust muffler is disposed on the left and right sides, and the rear side of the pair of left and right horizontal frames constituting the traveling aircraft body is configured as an inclined portion whose height increases toward the rear, The exhaust muffler is positioned between an intermediate frame connecting the transmission case and the rear axle case and the inclined portion of the horizontal frame, and the upper surface side of the exhaust muffler is inclined along the inclined portion of the horizontal frame. Therefore, the exhaust muffler can be increased in capacity while avoiding interference with auxiliary equipment such as the air cleaner around the engine. , It is possible to reduce the exhaust noise. Since the upper surface side of the exhaust muffler has an inclined surface that is not parallel to the lower surface side, the exhaust sound hardly resonates, and the exhaust sound muffling effect by the exhaust muffler is further enhanced. The engine side surface can be covered by the exhaust muffler having a larger size.

  In particular, according to the second aspect of the present invention, the suction fan for engine air cooling is provided on the left and right sides of the engine on the air cleaner side, so that the air cleaner is positioned upstream of the cooling air path by the suction fan. Then, the exhaust muffler is located on the downstream side. Therefore, the possibility that the air cleaner takes in the exhaust gas of the exhaust muffler can be suppressed, and the air cleaner and the exhaust muffler can be efficiently and compactly arranged around the engine. In addition, the large exhaust muffler can be efficiently air-cooled. Since the cooling air passage is between the intermediate frame and the inclined portion of the horizontal frame, the temperature rise of the horizontal frame is suppressed, and the exhaust heat of the engine and the exhaust muffler is reduced to the control seat side (operator side). ) Can be prevented.

It is a left view of the riding type rice transplanter in the embodiment. It is a top view of a riding type rice transplanter. It is a partial enlarged left side view of a riding type rice transplanter. It is a drive system figure of a riding type rice transplanter. It is the perspective view which looked at the engine and its surrounding structure from diagonally right rear. It is a rear view of an engine and its peripheral structure. It is an expanded side sectional view of the upper part of the air cleaner. It is a top view of a control seat and its periphery. It is a top view of the control seat of the state which removed the cover, and its periphery. It is a left view of an engine and its surrounding structure. It is a front view of a front bonnet. It is a left view of a front bonnet. It is a top view of a front bonnet. It is a separation perspective view explaining the attachment mode of a front visor body.

  Hereinafter, an embodiment embodying the present invention will be described with reference to the drawings in a case where the invention is applied to a four-row planting type rice transplanter (hereinafter simply referred to as a rice transplanter). In the following description, the left side in the traveling direction of the traveling machine body 1 is simply referred to as the left side, and the right side in the traveling direction is also simply referred to as the right side.

  First, an outline of a rice transplanter will be described with reference to FIGS. The rice transplanter of the embodiment includes a traveling machine body 1 supported by a pair of left and right front wheels 3 and a pair of left and right rear wheels 4 as traveling parts, and a seedling as a working part connected to the rear part of the traveling machine body 1 so as to be movable up and down. The planting device 2 is provided. The traveling body 1 is provided with a control seat 5 on which an operator sits, a control handle 6 disposed in front of the control seat 5, and a front bonnet 7 that covers the lower end side of the control handle 6. Below the steering handle 6 arranged at the center of the left and right width of the traveling machine body 1, a steering steering mechanism 8 for changing the direction of the left and right front wheels 3 is arranged. On the left and right sides of the front bonnet 7 in the traveling machine body 1, left and right spare seedling stands 9 on which a plurality of mat-like spare seedlings are placed in multiple stages are provided. In addition, it is possible to provide the fertilizer application apparatus (illustration omitted) which embeds granular fertilizer in the mud of the side of the seedling planted on the rice field behind the control seat 5. FIG.

  As shown in FIGS. 1 to 3, the traveling machine body 1 includes a machine body frame 11 and an engine 12. In the embodiment, the engine 12 is supported in an anti-vibration manner in the front and rear center portion of the body frame 11 below the control seat 5. The engine 12 is placed at a position along the longitudinal center line of the traveling machine body 1. That is, the engine 12 is positioned at the center of the left and right width of the traveling machine body 1. A transmission case 16 with a hydraulic continuously variable transmission 17 for shifting the power from the engine 12 is disposed in front of the engine 12. In this case, the crankshaft 13 of the engine 12 extends in the left-right direction, and an output pulley 14 is attached to one end of the crankshaft 13 protruding from the engine 12. The power of the engine 12 is transmitted to the transmission case 16 via a transmission belt 15 wound around the output pulley 14. The power of the engine 12 is transmitted to the front mission case 16 to drive the front wheels 3 and the rear wheels 4 so that the traveling machine body 1 travels forward and backward. In the embodiment, the hydraulic continuously variable transmission 17 is attached to the rear left side of the mission case 16. The power of the engine 12 is transmitted to the input shaft 18 of the hydraulic continuously variable transmission 17 by the transmission belt 15 via the input pulley 19. A tension pulley 20 is in contact with the transmission belt 15.

  As shown in FIGS. 3 to 5 and the like, the machine body frame 11 of the traveling machine body 1 includes a pair of left and right lateral frames 21 extending in the front-rear direction, a left and right laterally long front frame 22 that connects the front portions of the left and right lateral frames 21, and A left and right horizontally long rear frame 23 that connects rear end portions of the left and right horizontal frames 21 is provided. That is, the left and right lateral frames 21, the front frame 22, and the rear frame 23 constitute the body frame 11 of the traveling body 1. On the front side of the left and right horizontal frames 21, two front and rear branch frames 24 projecting outward in the left and right directions are fixed by welding. A left and right laterally long bumper frame 26 is connected to the front end portions of the left and right lateral frames 21 via a front bracket 25.

  Front axle cases 27 are attached to the left and right side surfaces of the front portion of the transmission case 16. A front wheel 3 is attached to a front axle 28 provided on the left and right front axle cases 27 so as to be steerable. A rear axle case 29 is disposed at the lower rear portion of the engine 12. The rear wheel 4 is attached to the rear axle 30 that protrudes left and right outward from the rear axle case 29. The transmission case 16 and the rear axle case 29 are connected to each other by a longitudinal cylindrical frame 31. The front portion of the engine 12 is supported by the cylindrical frame 31 via a front vibration isolation member 32 for vibration isolation. The rear portion of the engine 12 is supported on the rear axle case 29 by vibration isolation via a rear vibration isolation member 33. The left and right front axle cases 27 are connected to the front and rear middle portions of the corresponding left and right horizontal frames 21. The rear axle case 29 is provided with a pair of left and right rear struts 34 that are vertically long and inclined forward. The rear frame 23 is connected to the upper ends of the left and right rear columns 34. The power transmitted from the engine 12 to the transmission case 16 via the hydraulic continuously variable transmission 17 is transmitted to the left and right front axle cases 27 to drive the left and right front wheels 3 and to extend rearward from the transmission case 16. It is transmitted to the inside of the rear axle case 29 via 35 to drive the left and right rear wheels 4.

  As shown in FIGS. 1 and 2, the upper surface side of the traveling machine body 2 is covered with a vehicle body cover 40 on which an operator rides. A front bonnet 7 is erected on the front upper side of the vehicle body cover 40. The steering mechanism 8 is positioned below the front part of the vehicle body cover 40 (below the front bonnet 7). On the upper surface of the vehicle body cover 40, on the rear right side of the front bonnet 11, a step-type transmission pedal 41 and a brake pedal 42 are arranged side by side. The rice transplanter of the embodiment is configured to adjust the engine speed and the speed change power of the hydraulic continuously variable transmission 17 (acceleration / deceleration control) according to the depression amount of the speed change pedal 41.

  On the upper surface side of the front bonnet 7, the steering handle 6, the main speed change lever 43, a speed setting lever 44 as a speed setting operation tool (details will be described later), an accelerator lever 45 and a planting elevating lever 46 as a work clutch operation tool. Is arranged. In the embodiment, the main transmission lever 43 and the speed setting lever 44 are positioned on the left side with the steering handle 6 interposed therebetween, and the accelerator lever 45 and the planting lift lever 46 are positioned on the right side with the steering handle 6 interposed therebetween. The steering handle 6 is fixed to the upper end side of a handle shaft (not shown) in a handle post 37 erected on the upper surface of the steering mechanism 8. Note that a steering output shaft (not shown) protrudes downward on the lower surface side of the steering mechanism 8 and a steering rod mechanism 38 for steering the left and right front wheels 3 is connected to the steering output shaft. The main speed change lever 43 is used to switch the rice transplanter's travel mode between forward, neutral, reverse and seedling transfer modes, and the accelerator lever 45 is used to set and adjust the engine speed. The planting elevating lever 46 is used to elevate and lower the seedling planting device 2. However, the planting clutch (not shown) for switching power transmission to the seedling planting device 2 and the left and right side markers 64 are used. This selection operation can also be executed.

  An instrument panel 47 is provided on the upper surface of the front bonnet 7 to display the moving speed and the like. A headlamp 48 that illuminates the front of the traveling machine body 1 is provided on the upper front side of the front bonnet 7. A front visor body 49 surrounding the front of the instrument panel 47 is attached to the front upper end side of the front bonnet 7. The control seat 5 is supported behind the front bonnet 7 on the upper surface of the vehicle body cover 40 via a seat frame 36 connected to the body frame 11. A differential lock pedal 50 for turning on / off differential driving of the left and right front wheels 3 is arranged on the lower left side of the control seat 5 on the upper surface of the vehicle body cover 40.

  A pair of left and right rear struts 34 erected on the rear axle case 29 is connected to a four-row seedling planting device 2 through a lifting link mechanism 51 including a lower link 52 and a top link 53 so as to be lifted and lowered. . A cylinder base end side of a hydraulic planting elevating cylinder 54 is attached to the left and right center portion of the rear frame 23 so as to be vertically rotatable. The rod tip side of the planting elevating cylinder 54 is connected to the lower link 52. As a result of the vertical movement of the lifting / lowering link mechanism 51 by the expansion / contraction movement of the planting lifting / lowering cylinder 54, the seedling planting device 2 moves up and down.

  The seedling planting device 2 includes a planting input case 55 through which transmission power from the transmission case 16 is transmitted, two sets of four-row (one set of two) planting transmission cases 56 connected to the planting input case 55, A seedling planting mechanism 57 provided on the rear end side of the planting transmission case 56, a seedling mounting table 58 for four-row planting, and a float 59 for flattening on the surface arranged on the lower surface side of each planting transmission case 56. ing. The seedling planting mechanism 57 is provided with a rotary case 60 having two planting claws 61 for one line. Two rotary cases 60 are arranged for one planting transmission case 56. By one rotation of the rotary case 60, the two planting claws 61 cut out and hold one seedling each, and plant it on the rice field leveled with the float 59. On the front side of the seedling planting device 2, a leveling rotor 62 is provided so as to move up and down.

  The power transmitted from the engine 12 to the transmission case 16 is transmitted not only to the front wheels 3 and the rear wheels 4 but also to the planting input case 55 of the seedling planting device 2. Power from the transmission case 16 toward the seedling planting device 2 is once transmitted to the inter-shaft transmission case 63 (see FIG. 3) provided on the right side of the engine 12 (the front right side of the rear axle case 29). It is transmitted to the input case 55. Each seedling planting mechanism 57 and seedling mounting table 58 are driven by the power received by the planting input case 55. Although not shown, the inter-strain shifting case 63 has an inter-strain shifting mechanism that switches between planted seedlings to, for example, sparse planting, standard planting, or dense planting, and planting that interrupts power transmission to the seedling planting device 2. Built-in clutch. Side markers 64 are provided on the left and right sides of the seedling planting device 2. Based on the operation of the planting lift lever 46 on the front bonnet 7, the side marker 64 is divided into a working posture that forms a reference locus in the next process by landing on the surface and a non-working posture separated from the surface. The posture is changed and rotated.

  The operator gets on the vehicle body cover 40, operates the rice transplanter to move in the field, and drives the seedling planting device 2 to execute seedling planting work (rice planting work) for planting seedlings in the field. During the seedling planting operation, the seedling planting apparatus 2 is supplied with a seedling mat on the preliminary seedling stand 9 by the operator as needed.

  A rod-like auxiliary handle 130, which is an example of a guidance operation tool, is attached to the middle part of the bumper frame 26 located at the forefront of the traveling machine body 1 so as to be horizontally rotatable (see FIGS. 1 and 2). The auxiliary handle 130 is used by the operator to get down to the ground and guide the traveling machine body 1 when the vehicle moves at a steep slope such as traveling over a heel or traveling on and off. A grip portion 131 is provided on the distal end side of the auxiliary handle 130. The auxiliary handle 130 is turned into a stowed posture in a horizontal direction (a direction parallel to the bumper frame 26) and a usage posture protruding in a forward direction (a direction perpendicular to the bumper frame 26) by horizontal rotation with the base end side as a fulcrum. It can be changed.

  The grip portion 131 of the auxiliary handle 130 is provided with a travel lever (not shown) having a function (transmission and stop of the travel machine body 1) according to the speed change pedal 41. The travel lever is linked to the shift pedal 41 via an auxiliary travel wire (not shown). When the operator grips the traveling lever together with the grip portion 131, the shift pedal 41 is slightly depressed by the pulling action of the auxiliary traveling wire. For this reason, the traveling machine body 1 starts and travels at a very low speed corresponding to a slight depression amount of the shift pedal 41. When the operator releases his / her hand from the travel lever, the pulling action of the auxiliary travel wire is released and the speed change pedal 41 returns to its original posture. As a result, the traveling machine body 1 stops.

  Next, the power transmission system of the rice transplanter will be described with reference to FIG. In the transmission case 16, the transmission power through the hydraulic continuously variable transmission 17 including the hydraulic pump 101 and the hydraulic motor 102, the planetary gear mechanism 103, the hydraulic continuously variable transmission 17, and the planetary gear mechanism 103 is shifted to a plurality of stages. A gear-type sub-transmission mechanism 104, a main clutch 105 that interrupts power transmission from the planetary gear mechanism 103 to the gear-type sub-transmission mechanism 104, a brake mechanism 106 that brakes a shift output from the gear-type sub-transmission mechanism 104, and the like. I have. The hydraulic pump 101 is driven by power from the input shaft 18, hydraulic oil is supplied from the hydraulic pump 101 to the hydraulic motor 102, and transmission power is output from the hydraulic motor 102. Shift power from the hydraulic motor 102 is transmitted to the gear-type sub-transmission mechanism 104 via the planetary gear mechanism 103 and the main clutch 105. Then, power is transmitted from the gear-type auxiliary transmission mechanism 104 by branching in two directions, the front and rear wheels 3 and 4 and the seedling planting device 2.

  A part of the branching power toward the front and rear wheels 3 and 4 is transmitted from the gear-type auxiliary transmission mechanism 104 to the front axle 28 of the front axle case 27 via the differential gear mechanism 107 and the left and right differential output shafts 108. The left and right front wheels 3 are driven to rotate. The differential gear mechanism 107 is provided with a differential lock mechanism 109 that stops its own differential (drives the left and right differential output shafts 108 at a constant speed). By depressing the differential lock pedal 50 and engaging the differential lock body of the differential lock mechanism 109 with the differential gear case of the differential gear mechanism 107, the differential gear case is fixed to the differential output shaft 108 on the left and right sides. The differential function of the gear case is stopped, and the left and right differential output shafts 108 are driven at a constant speed.

  The remainder of the branching power directed to the front and rear wheels 3 and 4 is transmitted from the gear-type subtransmission mechanism 42 to the rear axle 30 of the rear axle case 29 via the bevel gear mechanism 99 and the travel drive shaft 35 to drive the left and right rear wheels 4 to rotate. Let When the brake mechanism 106 is operated, the output from the gear-type auxiliary transmission mechanism 104 is lost, so that the front and rear wheels 3 and 4 are braked. Further, when turning the rice transplanter, the friction clutch (not shown) inside the turning inside the rear axle case 29 is turned off to actuate the rear wheel 4 inside the turning freely, and the rear wheel outside the turning to which power is transmitted. It turns by the rotational drive of 4.

  The power directed toward the seedling planting device 2 is transmitted from the gear-type sub-transmission mechanism 42 to the inter-plant transmission case 63 (see FIG. 3) via the work power output mechanism 110, and is transmitted from the inter-plant transmission case 63 to the seedling planting device 2. Is done. In addition, when providing a fertilizer, power is transmitted from the inter-strain transmission case 63 to the fertilizer.

  Next, the peripheral structure of the engine 12 will be described mainly with reference to FIGS. As shown in FIGS. 3 and 5, the left and right horizontal frames 21 constituting the fuselage frame 11 extend horizontally in the front half of the front and rear halfway, and the rear half inclines upward and obliquely upward. Is bent. That is, the substantially second half of the left and right horizontal frames 21 is an inclined portion 21a that increases in height as it goes rearward. The inclination angle of the inclined portion 21 a of each horizontal frame 21 is substantially the same as the inclination angle of the engine 12. The engine 12 is generally positioned below the inclined portion 21a of each lateral frame 21 in a side view.

  As described above, the output pulley 14 is attached to one end portion of the crankshaft 13 protruding from the engine 12, and the suction fan (not shown) for engine air cooling is attached to the other end portion of the crankshaft 13. It is attached. In the embodiment, the output pulley 14 is attached to the left end portion of the crankshaft 13, and the suction fan is attached to the right end portion. The suction fan rotates integrally with the crankshaft 13. The suction fan is covered with a fan cover 151. A cooling air intake port 152 is formed at the center of the fan cover 151, and a dustproof net 153 is stretched over the cooling air intake port 152. The engine 12 is forcibly cooled by the cooling air taken from the cooling air intake port 152 by the rotation of the suction fan.

  An air cleaner 154 is disposed on one side of the rear portion of the engine 12 (on the suction fan (fan cover 151) side) to remove and purify the outside air and supply it to the intake system of the engine 12. An exhaust muffler 155 that reduces exhaust noise of the engine 12 and discharges exhaust gas is disposed on the other left and right sides (output pulley 14 side) of the rear part of the engine. An air cleaner 154 and an exhaust muffler 155 are distributed and arranged on the left and right sides of the engine 12. The air cleaner 154 is connected to the intake system of the engine 12. The exhaust muffler 155 is connected to the exhaust system of the engine 12. The outside air filtered by the air cleaner 154 is supplied to the intake system of the engine 12. Exhaust gas discharged from each cylinder of the engine 12 to the exhaust system is discharged to the outside via the exhaust muffler 155.

  The air cleaner 154 and the suction fan are on the same side (right side) with respect to the engine 12. That is, the air cleaner 154 is located upstream of the cooling air path by the suction fan, and the exhaust muffler 155 is located downstream. Therefore, the possibility that the air cleaner 154 takes in the exhaust gas of the exhaust muffler 155 can be suppressed, and the air cleaner 154 and the exhaust muffler 155 can be efficiently and compactly arranged around the engine 12.

  An air cleaner 154 disposed on the right side of the rear portion of the engine 12 with a suction fan includes a vertically long box-like cleaner body 154a. As shown in FIG. 7, the upper and lower sides of the cleaner body 154a are provided with an upwardly opening cylindrical intake cylinder portion 154b communicating with the cleaner body 154a so as to protrude upward. The upward opening of the intake cylinder portion 154b is an intake port 154c that takes in outside air. A plurality of outwardly extending ribs 154d are fixed to the intake cylinder portion 154b, and a mesh plate 154e (mesh plate) is attached to the upper surface side of the rib 154d group. Further, a silencer cover 156 as a silencer that covers the intake cylinder part 154b together with the mesh plate 154e from above is detachably attached to the intake cylinder part 154b.

  A labyrinth-like (U-turn) path from the mesh of the mesh plate 154e to the intake port 154c of the intake cylinder portion 154b through the inside of the silencer cover 156 constitutes the outside air guide path 157. The outside air is sent from the intake cylinder portion 154b to the cleaner body 154a through the labyrinth-like outside air guide path 157. As the outside air passes through the labyrinth-like outside air guide path 157, the intake sound is attenuated. The presence of the outside air guide path 157 prevents foreign matter such as muddy water and sawdust that the wheel 4 has sprung up after traveling in the field from entering the air cleaner 154 (cleaner body 154a), thereby extending the life of the air cleaner 154 and sealing it. We are trying to improve the performance. Since the sound deadening cover body 156 is detachable, maintenance work such as cleaning the inside of the cleaner body 154a and the like is easy.

  As shown in FIGS. 8 and 9, the engine 12 is located below the rear portion of the vehicle body cover 40 (below the control seat 5). The control seat 5 is in a position overlapping the front side of the engine 12 in plan view. A maintenance hole 158 is formed in the body cover 40 behind the control seat 5. The maintenance hole 158 is closed with a detachable or openable lid 159. The lid body 159 of the embodiment is configured to be detachable using butterfly bolts. The maintenance hole 158 faces the rear portion of the engine 12 (including the air cleaner 154). The muffler cover 156 of the air cleaner 154 is exposed from the maintenance hole 158 from which the lid 159 is removed. Therefore, if the cover 159 is removed, the hand reaches the air cleaner 154 from the body cover 40, and the work required for the maintenance work on the air cleaner 154 can be reduced, and the maintenance workability of the air cleaner 154 can be improved.

  As shown in FIGS. 5, 6, and 10, the exhaust muffler 155 disposed on the left rear side of the engine 12 includes a substantially box-shaped muffler main body 155 a that covers the rear left side of the engine. In the embodiment, the muffler main body 155a is positioned between the cylindrical frame 31 as an intermediate frame and the inclined portion 21a of the left lateral frame 21. The upper surface side of the muffler main body 155a is configured as an inclined surface 155b that is inclined rearward and upward along the inclined portion 21a of the left lateral frame 21. As shown in FIGS. 6 and 8 to 10, the exhaust muffler 155 is located between the engine 12 and the left rear wheel 4. That is, since the left rear wheel 4 with a lug is located on the left outer side of the muffler main body 155a (exhaust muffler 155), the capacity of the muffler main body 155a cannot be increased in the left-right direction. In this respect, in the embodiment, the capacity of the exhaust muffler 155 is increased by making the upper surface side of the muffler main body 155a an inclined surface 155b and making the muffler main body 155a substantially trapezoidal in a side view. In addition, since the upper surface side of the muffler main body 155a is an inclined surface 155b that is not parallel to the lower surface side, the exhaust sound hardly resonates, and the exhaust sound muffling effect by the exhaust muffler 155 is further enhanced.

  The muffler main body 155 a also functions as a protective cover that covers the rear portion of the left side surface of the engine 12. An exhaust pipe 159 protruding from the exhaust manifold of the engine 12 is directly connected to the right side surface of the muffler body 155a. A tail pipe 160 protrudes rearward from the back side of the muffler body 155a. Exhaust gas discharged from each cylinder of the engine 12 is supplied to the exhaust muffler 155 via the exhaust pipe 159 and is discharged to the outside from the exhaust port of the tail pipe 160.

  As apparent from the above description and FIGS. 5 to 7, the engine 12 is mounted between the front and rear axles 28, 30 of the traveling machine body 1, and the control seat 5 is disposed on the vehicle body cover 40 that covers the engine 12 from above. In the working vehicle, the air cleaner 154 is disposed on the left and right sides of the engine 12 and the air inlet 154c of the air cleaner 154 is opened upward, so that the rear wheel 4 is located in the vicinity of the air cleaner 154. However, it is possible to suppress the risk of taking in the muddy water or the like splashed by the rear wheel 4 traveling in the field into the air cleaner 154, and it is easy to maintain the purification performance of the air cleaner 154. In particular, in the present invention, the intake port 154c is covered with a silencer 156 from above, and a labyrinth-like outside air guide path 157 is formed between the intake port 154c and the silencer 156. Intrusion of muddy water or the like into the air cleaner 154 can be reliably prevented while efficiently exhibiting the above.

  Further, a suction fan for engine air cooling is provided on one side of the engine 12 that is the air cleaner 154 side, and an exhaust muffler 155 is disposed on the other side of the left and right sides of the engine 12, so that the suction The air cleaner 154 is located upstream of the cooling air path by the fan, and the exhaust muffler 155 is located downstream. Therefore, the possibility that the air cleaner 154 takes in the exhaust gas of the exhaust muffler 155 can be suppressed, and the air cleaner 154 and the exhaust muffler 155 can be efficiently and compactly arranged around the engine 12.

  As is apparent from the above description and FIGS. 8 and 9, a maintenance hole 158 having a removable lid 159 is formed in the vehicle body cover 40 at the rear of the control seat 5, and the air cleaner 154 is maintained in the maintenance. Since the hole 158 faces from below, the labor required for maintenance work on the air cleaner 154 can be reduced, and the maintenance workability of the air cleaner 154 can be improved.

  As apparent from the above description and FIGS. 5, 6, and 10, the engine 12 and the transmission case 16 are mounted between the front and rear axles 28 and 30 of the traveling machine body 1 and cover the engine 12 and the transmission case 16. In the work vehicle in which the control seat 5 is disposed on the cover 40, the air cleaner 154 is disposed on one side of the left and right sides of the engine 12 and the exhaust muffler 155 is disposed on the other side of the left and right. The rear side of the paired left and right horizontal frames 21 is configured as an inclined portion 21a that increases in height toward the rear, an intermediate frame 31 that connects the transmission case 16 and the rear axle case 29, and the horizontal frame 21 The exhaust muffler 155 is positioned between the inclined portion 21 a and the upper surface side of the exhaust muffler 155 is positioned on the horizontal frame 21. Because they are inclined to and along the inclined portion 21a, while avoiding interference with the auxiliary devices such as the air cleaner 154 Surrounding the engine 12, Hakare capacity up of the exhaust muffler 155, thereby reducing the exhaust noise. Since the upper surface side of the exhaust muffler 155 is an inclined surface 155b that is not parallel to the lower surface side, the exhaust noise hardly resonates, and the exhaust noise suppression effect by the exhaust muffler 155 is further enhanced. The engine exhaust side 155 can cover the engine side surface.

  As is clear from the above description and FIGS. 5, 6, and 10, the suction fan for air cooling of the engine 12 is provided on one side of the left side of the engine 12 that is the air cleaner 154 side. Thus, the air cleaner 154 is positioned upstream of the cooling air path and the exhaust muffler 155 is positioned downstream. Therefore, the possibility that the air cleaner 154 takes in the exhaust gas of the exhaust muffler 155 can be suppressed, and the air cleaner 154 and the exhaust muffler 155 can be efficiently and compactly arranged around the engine 12. The large exhaust muffler 155 can be efficiently air-cooled. Since the space between the intermediate frame 31 and the inclined portion 21a of the horizontal frame 21 serves as the cooling air passage, the temperature rise of the horizontal frame 21 is suppressed, and the exhaust heat of the engine 12 and the exhaust muffler 155 is reduced. It is possible to prevent heading toward the control seat 5 side (operator side).

  Next, a detailed structure around the front bonnet 7 will be described with reference to FIGS. As described above, the instrument panel 47 for displaying the moving speed and the like is provided on the upper surface of the front bonnet 7. In the embodiment, the instrument cover body 161 is attached to the upper surface of the front bonnet 7, and the instrument panel 47 is assembled to the instrument cover body 161 so as to be exposed upward. The steering handle 6, the main speed change lever 43, the speed setting lever 44, the accelerator lever 45, and the planting lift lever 46 protrude upward from the instrument cover body 161.

  A headlamp 48 that illuminates the front of the traveling machine body 1 is provided on the upper front side of the front bonnet 7. A front visor body 49 surrounding the front of the instrument panel 47 is attached to the front upper end side of the front bonnet 7. In the embodiment, a pair of left and right mounting bosses 162 project forward from the front side of the instrument cover body 161. The front visor body 49 is detachably attached to the instrument cover body 161 by screwing the front visor body 49 to the left and right mounting boss portions 162 with a plurality of screws 163 from the front. When the front visor body 49 is attached to the instrument cover body 161, the presence of both the left and right mounting boss portions 162 causes the front visor body 49 and the instrument cover body 161 (may be referred to as the front bonnet 7) to be placed between the front visor body 49 and the instrument cover body 161. An upper and lower opening-shaped gap 164 is formed. The lower end side of the front visor body 49 overlaps the upper end side of the headlamp 48.

  In the above-described configuration, the upward irradiation light, which is less related to the irradiation of the field or the like, is applied to the lower rear side of the front visor body 49, and the irradiation light is applied from the rear side of the front visor body 49. By wrapping around or reflecting on the back surface of the front visor body 49, the upper surface of the instrument cover body 161 and thus the instrument panel 47 can be irradiated with irradiation light. For this reason, it becomes easy to visually recognize the instrument panel 47 at dusk or at night without providing a dedicated lamp or the like for night illumination (the visibility of the instrument panel 47 can be improved). Whether or not the headlight 48 is lit at dusk or at night can be determined by the brightness on the instrument panel 47, and problems such as non-lighting or forgetting to turn off at dusk or at night can be avoided.

  The present invention is not limited to the above-described embodiment, and can be embodied in various forms. The configuration of each part is not limited to the illustrated embodiment, and various modifications can be made without departing from the spirit of the present invention.

1 traveling machine body 2 seedling planting device 3 front wheel 4 rear wheel 5 control seat 6 control handle 7 front bonnet 12 engine 16 mission case 47 instrument panel 48 headlight 49 front visor body 151 fan cover 152 cooling air intake 153 dustproof Net 154 Air cleaner 154c Inlet 154d Flange 155 Exhaust muffler 155a Muffler body 155b Inclined surface 156 Silencer cover 156a Annular groove 157 Outside air guide path 158 Maintenance hole 159 Exhaust pipe 160 Tail pipe

Claims (3)

In a work vehicle in which an engine and a transmission case are mounted between the front and rear axles of the traveling body, and a control seat is disposed on a vehicle body cover that covers the engine and the transmission case.
An air cleaner is arranged on one side of the left and right sides of the engine, an exhaust muffler is arranged on the other side of the left and right sides, and the rear side of the pair of left and right horizontal frames constituting the traveling aircraft body becomes higher toward the rear Configured to be an inclined part,
The exhaust muffler is positioned between an intermediate frame connecting the transmission case and the rear axle case and the inclined portion of the horizontal frame, and the upper surface side of the exhaust muffler is inclined along the inclined portion of the horizontal frame. Let
Work vehicle. A suction fan for engine air cooling is provided on one side of the engine that is on the air cleaner side.
The work vehicle according to claim 1. Between the left and right sides across the engine and below the air cleaner, the inter-transmission transmission is located,
The work vehicle according to claim 2.

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