JP2016030575A - Work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work vehicle that attains light weighting of a travelling vehicle body and also has a vehicle body structure furnished with rigidity.SOLUTION: The work vehicle is equipped with a diesel engine 5 serving as driving source and travelling portions 13 and 19 that are driven based on power of the diesel engine 5; and constitutes a travelling vehicle body 2 by connecting a pair of left and right front frames 14 to a pair of left and right rear frames 15 in a longitudinal direction. Respective front ends of the pair of left and right frames 14 are erected by a connecting member 12 made of a rectangular metal cast so that the diesel engine 5 is supported on the front frames 14.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a work vehicle such as a tractor for agricultural work or a wheel loader for civil engineering work.

  In a work vehicle such as a tractor, a front body frame extending forward of the traveling body relative to the diesel engine and a rear body frame connected to the rear of the diesel engine constitute a body frame of the traveling body. (See Patent Document 1). The work vehicle of patent document 1 has comprised the clutch housing produced from the diesel engine toward the back of the body with the transmission case, and comprises the rear body frame of the traveling body. On the other hand, the front fuselage frame is extended toward the front of the traveling aircraft on the lower side of the diesel engine.

  In addition, due to the recent application of high-level exhaust gas regulations related to diesel engines, exhaust gas purification that purifies air pollutants in exhaust gases on agricultural machinery, construction machinery, ships, etc. equipped with diesel engines. There is a growing demand for mounting post-processing devices such as devices. Thus, some conventional work vehicles such as tractors have an exhaust gas purification device disposed in the engine room under the hood together with the diesel engine when the exhaust gas purification device is mounted (see Patent Document 2).

JP2013-233902A JP 2013-116692 A

  By the way, as in Patent Document 1, when the rear body frame is configured with a clutch housing and a transmission case, it is difficult to access the gear mechanism assembled in the case, and not only the assembly work and maintenance work become complicated, This prevents the weight of the traveling aircraft from being reduced. On the other hand, when a diesel engine having an exhaust gas countermeasure device as in Patent Document 2 is applied to a work vehicle such as a tractor, it is necessary to mount an exhaust gas purification device that becomes a heavy object. Therefore, the frame constituting the traveling body is required to have rigidity.

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

  The present invention includes an engine that serves as a drive source and a traveling unit that is driven based on the power of the engine, and a working vehicle that forms a traveling machine body by connecting the left and right front frames and the left and right rear frames back and forth. The front end of each of the left and right front frames is constructed by a rectangular metal casting connecting member, and the engine is supported on the front frame.

  In the work vehicle, the connecting member is configured to be divided into front and rear, the side surface of the rear part of the connecting member is connected to the inner surface of the front end of the front frame, and the front part of the connecting member is connected to the rear part. It is connected to the front face so that the front part can be replaced.

  Moreover, the said working vehicle WHEREIN: The said connection member is good also as what provided the recessed part used as the groove shape along the front-back direction in the center position of the upper surface.

  When configured in this manner, the apparatus further includes a transmission unit that transmits the power of the engine to the traveling unit, and the front ends of the left and right front frames are constructed by rectangular connecting members, and the engine is mounted on the front frame. The rear end of each of the left and right rear frames is connected to the left and right side surfaces of the transmission unit, the front frame having a different length can be replaced according to the vehicle type, and the length of the front frame is increased. It is good also as what can comprise the traveling body according to a vehicle type by changing.

  Further, the front end of each of the left and right rear frames is constructed with a beam frame, and each of the left and right front frames is connected to the left and right rear frames via a spacer, thereby making the left and right rear frames more rigidly supported. The support of the traveling machine body may be stabilized. In addition, by connecting the front and rear of the rear frame with a beam frame serving as a strength member and a mission unit, a traveling machine body having rigidity can be configured. Since the rear frame can be supported with high rigidity, heavy objects such as a control seat and a fuel tank can be concentrated and supported on the rear frame side.

  When configured in this way, the rear frame includes a front through hole to be connected to the beam frame, and a rear through hole to be connected to the mission portion, and the mission portion is the left and right side surfaces thereof, and A connecting hole is provided at a position opposite to the rear through hole, and when the rear frame is connected to the mission part, the inner side surface of the rear frame is brought into contact with the outer side surface of the mission part, and the through hole A connecting pin having a through-hole is inserted into the connecting hole of the transmission unit through the rear through-hole, and a bolt is inserted into the connecting pin and screwed into the connecting hole. By adopting a configuration for receiving the inner surface of the frame, the moment generated on the left and right can be suppressed, and the offset of the rear frame fixed at the mission section can be prevented. Accordingly, it is possible to prevent distortion in the traveling machine body and stabilize the structure of the traveling machine body.

  In the work vehicle described above, on the lower surface of the connecting member, a restricting member that restricts a left-right tilt range in the front axle case of the traveling unit can be attached and detached, and the rigid connecting member is connected by the front axle case. It is good also as what can improve the intensity | strength of the said traveling body by making it support. At this time, there are connecting legs connected to the upper surface of the front axle case on the front and back surfaces of the connecting member, and the attachment and detachment positions of the restricting member are on both the left and right sides of the connecting member, It may be possible to reduce the burden on the airframe during traveling by positioning the front axle case with the rigid connecting member located between the leg portions for use.

  According to this invention, an engine support structure can be strengthened by fixing the front part frame which supports an engine with the connection member used as a metal casting. Moreover, the strength of the traveling machine body can be improved by configuring the connecting member as a strength member. Therefore, the traveling machine body can be configured with the front frame and the rear frame to reduce the weight of the traveling machine body, and at the same time, the traveling machine body can be configured with high rigidity by being fixed by the connecting member of the metal casting. Then, by configuring the traveling machine body with the front frame and the rear frame, it is possible to easily assemble traveling machine bodies corresponding to a plurality of models by simply combining the front frame and the rear frame having different frame shapes.

  Further, according to the present invention, by adopting a configuration in which the connecting member is divided into the front and rear, it is possible to cope with a plurality of types of machine body configurations and to share parts. And by exchanging the front and rear parts of the connecting member, it can be configured to match the center of gravity of each model, so that the center of gravity of the work machine can be stabilized. Furthermore, by providing a recess having a groove shape along the front-rear direction at the center position of the upper surface of the connecting member, the front PTO shaft directly connected to the front of the engine can be easily arranged, and the types of models can be diversified.

It is a left view of a tractor. It is a top view of a tractor. It is a right view of a tractor. It is a front view of a tractor. It is left side explanatory drawing of a traveling body. It is right side explanatory drawing of a traveling body. It is the perspective view which looked at the traveling body from diagonally left rear. It is the perspective view which looked at the traveling machine body from diagonally right rear. It is a perspective view which shows the structure in the bonnet seen from the right diagonal front. It is a left side enlarged view of a tractor. It is a perspective view which shows the bonnet back surface structure seen from the cabin side. It is a perspective view which shows the structure of the engine room seen from the diagonally right front. It is a perspective view which shows the structure of the engine room seen from diagonally left rear. It is a perspective view which shows the structure of the engine room frame seen from diagonally right back. It is a perspective view which shows the structure of the engine room frame seen from the diagonally lower left. It is a disassembled perspective view which shows the structure of the traveling body seen from right diagonally forward. It is a left side enlarged view of a traveling machine body. It is a perspective view which shows the connection structure of a traveling machine body front part. It is a partial cross section figure which shows the connection structure of a front axle case and a frame connection member. It is explanatory drawing which shows the inclination control range of the front axle case by a frame connection member. It is a disassembled perspective view which shows the structure of a traveling machine body front part. It is a disassembled perspective view which shows the structure of the traveling body seen from right diagonally backward. It is a partial cross section figure which shows the connection structure of a mission case and a traveling body. It is a side view of the traveling body which has a different body structure.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, taking a tractor as a work vehicle as an example.

  First, an outline of the tractor 1 will be described with reference to FIGS. The traveling machine body 2 of the tractor 1 in the embodiment is supported by a pair of left and right rear wheels 4 as well as a pair of left and right front wheels 3 as a traveling unit. The tractor 1 is configured to travel forward and backward by driving the rear wheels 4 and the front wheels 3 with a common rail type diesel engine 5 (hereinafter simply referred to as an engine) as a power source mounted on the front portion of the traveling machine body 2. Has been. The engine 5 is covered with a bonnet 6. A cabin 7 is installed on the upper surface of the traveling machine body 2. Inside the cabin 7, a steering seat 8 and a steering handle (round handle) that moves the steering direction of the front wheel 3 to the left and right by steering. 9 are arranged. A step 10 on which the operator gets on and off is provided at the outer lower portion of the cabin 7. A fuel tank 11 that supplies fuel to the engine 5 is provided below the bottom of the cabin 7.

  The traveling machine body 2 includes an engine frame (front frame) 14 having a front bumper (frame connecting member) 12 and a front axle case 13, and left and right machine body frames (rear frame) 15 detachably fixed to the rear part of the engine frame 14. It is comprised by. A front axle 16 is rotatably protruded outward from the left and right ends of the front axle case 13. The front wheels 3 are attached to the left and right ends of the front axle case 13 via the front axle 16. A transmission case 17 is connected to the rear part of the body frame 15 for appropriately changing the rotational power from the engine 5 and transmitting it to the front and rear four wheels 3, 3, 4, 4. A tank frame 18 having a rectangular frame plate shape in a bottom view projecting outward in the left and right directions is bolted to the lower surface sides of the left and right body frames 15 and the mission case 17. The fuel tank 11 of the embodiment is divided into left and right two parts. The left and right fuel tanks 11 are distributed and mounted on the upper surface side of the left and right projecting portions of the tank frame 18. The left and right rear axle cases 19 are mounted on the left and right outer surfaces of the mission case 17 so as to protrude outward. Left and right rear axle cases 20 are rotatably inserted in the left and right rear axle cases 19. The rear wheel 4 is attached to the mission case 17 via the rear axle 20. Upper portions of the left and right rear wheels 4 are covered with left and right rear fenders 21.

  A hydraulic lifting mechanism 22 that lifts and lowers a working machine such as a rotary tiller is detachably attached to the rear upper surface of the mission case 17. A working machine such as a rotary tiller is connected to the rear portion of the transmission case 17 via a three-point link mechanism including a pair of left and right lower links 23 and a top link 24. On the rear side surface of the mission case 17, a PTO shaft 25 for transmitting a PTO driving force to a working machine such as a rotary tiller is provided to project rearward.

  A flywheel 26 is attached to an engine output shaft (not shown) projecting rearward from the rear side surface of the engine 5. A main drive shaft 27 protruding backward from the flywheel 26 and a main transmission input shaft 28 protruding forward from the front side of the transmission case 17 are connected via a power transmission shaft 29 having universal shaft joints at both ends. In the transmission case 17, a hydraulic continuously variable transmission, a forward / reverse switching mechanism, a traveling auxiliary transmission gear mechanism, and a differential gear mechanism for rear wheels are arranged. The rotational power of the engine 5 is transmitted to the main transmission input shaft 28 of the transmission case 17 via the main driving shaft 27 and the power transmission shaft 29, and is appropriately shifted by the hydraulic continuously variable transmission and the traveling auxiliary transmission gear mechanism. Then, the transmission power is transmitted to the left and right rear wheels 4 through the rear wheel differential gear mechanism.

  The front wheel output shaft 30 projecting forward from the lower front portion of the transmission case 17 projects rearward from the front axle case 13 containing a front wheel differential gear mechanism (not shown) via a front wheel drive shaft 31. A front wheel transmission shaft (not shown) is connected. Transmission power by the hydraulic continuously variable transmission and the traveling auxiliary transmission gear mechanism in the transmission case 17 is transmitted from the front wheel output shaft 30, the front wheel drive shaft 31, and the front wheel transmission shaft to the front wheel differential gear mechanism in the front axle case 13. Is transmitted to the left and right front wheels 3 via.

  Next, the internal structure of the bonnet 6 will be described with reference to FIGS. The diesel engine 5 has a cylinder head mounted on a cylinder block containing an engine output shaft and a piston. The intake manifold 203 is disposed on the right side of the cylinder head, and the exhaust manifold 204 is disposed on the left side of the cylinder head. . That is, the intake manifold 203 and the exhaust manifold 204 are distributed and arranged on both side surfaces along the engine output shaft in the engine 5. The cooling fan 206 is disposed on the front surface of the cylinder block in the diesel engine 5, while the flywheel 26 is disposed on the rear surface of the cylinder block. That is, the flywheel 26 and the cooling fan 206 are arranged separately on both side surfaces intersecting the engine output shaft in the engine 5.

  The diesel engine 5 includes a fuel supply pump 207 for supplying fuel, a cylindrical common rail 208 for pumping fuel to the injector, a fuel filter 209 for removing foreign matter from the fuel from the fuel tank 11, an intake manifold 203, A connected EGR device 210 is provided on the right side surface thereof. The fuel in the fuel tank 11 is supplied to the fuel supply pump 207 by the fuel pressure pump 213 via the fuel filter 209, and then pumped to the common rail 208 from the fuel supply pump 207. Accordingly, since the high-pressure fuel is stored in the common rail 208, the high-pressure fuel in the common rail 208 is injected into each cylinder of the engine 5 from each injector by controlling the fuel injection valve of each injector.

  The diesel engine 5 includes a turbocharger 211 that compresses air using exhaust gas from the exhaust manifold 204, and an EGR cooler 212 that cools a part of the exhaust gas from the exhaust manifold 204 and recirculates it to the EGR device 210. Prepare on the left side. The turbocharger 211 includes a compressor case with a built-in blower wheel. The intake side of the compressor case is connected to the intake / exhaust side of the air cleaner 221 via the intake pipe 222, while the intake / exhaust side of the compressor case is connected. Is connected to the intake relay pipe (intake upstream side) 223. The turbocharger 211 includes a turbine case with a built-in turbine wheel. The exhaust intake side of the turbine case is connected to the exhaust gas outlet of the air manifold 204, while the intake / exhaust side of the turbine case is connected to an aftertreatment device. It is connected to an exhaust gas inlet of a certain exhaust gas purification device 224.

  In the diesel engine 5, the EGR cooler 212 and the EGR device 210 that are arranged on both side surfaces are connected by a recirculation exhaust gas pipe 214 that bypasses the rear surface of the engine 5 (on the flywheel 26 side) as a reflux line. The EGR device 210 is connected to an intake relay pipe (intake downstream side) 225 extending forward (on the cooling fan 206 side) on the right side of the engine 5. The intake relay pipes 223 and 225 are respectively arranged on both sides of the diesel engine 5, and are connected to an intercooler (not shown) installed in a frame frame 226 in front of the diesel engine 5. It extends toward the front upper side. Further, the air cleaner 221 is disposed on the upper front side of the frame frame 226, and the intake pipe 222 connected to the air cleaner 221 extends over the frame frame 226 and extends behind the left side of the diesel engine 5.

  With the above configuration, fresh air (external air) sucked into the air cleaner 221 is removed by the air cleaner 221 and purified and then sucked into the compressor case of the turbocharger 211 via the intake pipe 222. The pressurized fresh air compressed in the compressor case of the turbocharger 211 is supplied to the EGR main body case of the EGR device 210 via the intake relay pipes 223 and 225 and the intercooler. On the other hand, a part of the exhaust gas (EGR gas) from the exhaust manifold 204 is cooled by the EGR cooler 212 and then supplied to the EGR main body case of the EGR device 210 via the recirculation exhaust gas pipe 214.

  The EGR device 210 mixes the pressurized fresh air from the turbocharger 211 and the EGR gas from the exhaust manifold 204, and then supplies the mixed gas to the intake manifold 203. That is, a part of the exhaust gas discharged from the diesel engine 5 to the exhaust manifold 204 is recirculated to the intake manifold 203, whereby the maximum combustion temperature during high load operation is lowered, and NOx (nitrogen oxidation from the diesel engine 5). Waste) will be reduced.

  The diesel engine 5 includes a continuous regeneration type exhaust gas purification device 224 (DPF). The exhaust gas purification device 224 removes particulate matter (PM) in the exhaust gas discharged from the engine 5 and reduces carbon monoxide (CO) and hydrocarbons (HC) in the exhaust gas. An exhaust gas purification device 224 is disposed above the exhaust manifold 204 on the upper surface side of the diesel engine 5. The exhaust gas purification device 224 has a substantially cylindrical shape extending long in the front-rear direction parallel to the output shaft (crankshaft) of the diesel engine 5, and both front and rear sides of the exhaust gas purification device 224 (upstream in the exhaust gas movement direction). And the downstream side) are provided with an exhaust gas inlet and an exhaust gas outlet.

  The exhaust gas purification device 224 has an exhaust gas inlet provided on the outer peripheral surface of the case on one end side (rear side) in the longitudinal direction, and the exhaust gas inlet is connected to the exhaust gas discharge side of the turbine case in the turbocharger 211. . The exhaust gas purification device 224 has an exhaust gas outlet provided on the outer peripheral surface of the case on the other end side (front side) in the longitudinal direction, and the exhaust gas outlet is connected to the exhaust pipe 227. In the exhaust gas purification device 224, the exhaust gas inlet opens downward, while the exhaust gas outlet opens upward on the right side. The exhaust pipe 227 is disposed so as to straddle the upper part of the diesel engine 5 from the front left side to the rear right side of the diesel engine 5.

  The lower end side of the exhaust relay bracket 215 constituting the support body (DPF support body) of the exhaust gas purification device 224 is bolted to the exhaust manifold 204. The exhaust relay bracket 215 forms an exhaust relay pipe as an exhaust relay path on the upper side thereof. The exhaust relay bracket 215 bolts the exhaust intake side of the exhaust relay pipe to the exhaust discharge side of the turbine case in the turbocharger 211, while the exhaust discharge side of the exhaust relay pipe 85 is connected to the exhaust gas purification device 224. It is fastened to the exhaust gas inlet. Therefore, the exhaust manifold 7 and the exhaust gas purification device 224 communicate with each other via the turbine case in the turbocharger 211 and the exhaust relay pipe of the exhaust relay bracket 215.

  The engine 5 includes an outlet side bracket body 216 and an inlet side bracket body 217 as a housing support body that supports and fixes the exhaust gas purification device 224. The outlet side bracket body 216 and the inlet side bracket body 217 are arranged upright on the front side and the rear side that intersect the engine output shaft in the cylinder head of the engine 5. The inlet side bracket body 217 is located on the rear surface side of the engine 5 and supports the exhaust intake side of the exhaust gas purification device 224. The outlet side bracket body 216 is located on the front side of the engine 5 and supports the exhaust discharge side of the exhaust gas purification device 224.

  The lower end side of the inlet side bracket body 217 is bolted to the rear surface of the cylinder head in the engine 5. The upper end side of the inlet side bracket body 217 is fastened to the inlet side lid body of the exhaust gas purifying device 224 via the relay bracket 219. In addition, a part of the rear surface on the lower end side of the inlet side bracket body 217 is protruded, and the support plate 218 is fastened to the protrusion portion. By arranging the inlet-side bracket body 217 and the support plate 218 in the front-rear direction and connecting them, the EGR device 210 is interposed between the inlet-side bracket body 217 and the support plate 218 without impairing the support strength of the exhaust gas purification device 224. And a recirculation exhaust gas 214 for connecting the EGR cooler 212 to each other can be provided.

  Above the diesel engine 5, the exhaust gas purifying device 224 and the exhaust pipe 227 are arranged side by side so as to be parallel to the output shaft of the diesel engine 5. That is, the exhaust gas purification device 224 and the exhaust pipe 227 are arranged side by side so that the exhaust gas purification device 224 covers the left side of the upper surface of the diesel engine 5 while the exhaust pipe 227 covers the right side of the upper surface of the diesel engine 5.

  The exhaust pipe 227 connected to the exhaust side of the exhaust gas purification device 224 is connected to the tail pipe 229 via a bellows pipe 228 erected on the rear right side of the diesel engine 5. The tail pipe 229 extends from the lower side to the upper side on the front right side of the cabin 7 and has a shape bent toward the diesel engine 5 on the lower side of the cabin 7. The tail pipe 229 is formed such that the lower bent portion straddles the upper part of the body frame 15 from the inside to the outside. Further, the tail pipe 229 is configured to be covered with a heat shield plate 230 except for the upper end portion thereof.

  Next, the configuration of the engine room frame under the hood 6 will be described with reference to FIGS. The bonnet 6 forms a front grill 231 on the front lower side and covers the front of the engine room. An engine cover 232 formed of a perforated plate is disposed on the lower left and right sides of the bonnet 6 to cover the left and right sides of the engine room. That is, the hood 6 and the engine cover 232 cover the front, upper, and left and right sides of the diesel engine 5.

  The pair of left and right engine frames (front frames) 14 have their front end side inner surfaces connected to the left and right outer surfaces of the frame connecting member 12. The frame connecting member 12 is made of a rectangular metal casting, and the diesel engine 5 is supported on the engine frame 14 installed by the frame connecting member 12. The frame connecting member 12 is configured to be divided into a front part (front bumper part) 12a and a rear part (axle case connecting part) 12b. The front axle case 13 is connected to the bottom surface side of the axle frame connecting portion 12b, and the front axle case 13 is suspended and supported by the engine frame 14. The front bumper 12a is installed at a position in contact with the front end surface of the engine frame 14 by being connected to the front surface of the axle case connecting portion 12b.

  A frame bottom plate 233 is installed on the upper edges of the left and right engine frames 14 and the upper surface of the front bumper 12 so as to cover the upper front side of the engine frame 14. The lower surface of the frame bottom plate 233 is connected to the side surfaces of the left and right engine frames 14 via a connection bracket 233a. Each of the connection brackets 233a arranged on the left and right sides has one end connected to the side surface of the engine frame 14 and the other end connected to the side edge side of the lower surface of the frame bottom plate 233. An under cover 296 that covers the lower front side of the engine 5 is disposed at the rear end of the frame bottom plate 233. The under cover 296 has a front end connected to the frame bottom plate 233 and a rear left and right side edge connected to the left and right engine frames 14. The under cover 296 includes a front part that extends from the rear end of the frame bottom plate 233 toward the lower end of the engine frame 14, and a rear part that extends forward and below the engine 5.

  A radiator 235 having a fan shroud 234 attached to the back side is erected on the frame bottom plate 233 so as to be positioned on the front side of the engine 5. The fan shroud 234 surrounds the outer peripheral side of the cooling fan 206 and allows the radiator 235 and the cooling fan 206 to communicate with each other. The fan shroud 234 has an upper shielding part 234a whose upper end has a T-shaped cross section, and a side shielding part 234b that protrudes from the left and right side surfaces. The upper shielding portion 234a is disposed so as to extend in the left-right direction over the entire upper surface of the fan shroud 234, and has a configuration in which the upper end thereof is brought close to the lower surface of the ceiling portion 259 of the bonnet 6 when the bonnet 6 is closed. The pair of left and right side shielding portions 234b are arranged so as to extend in the vertical direction over the entire left and right side surfaces of the fan shroud 234, and when the bonnet 6 is closed, the left and right ends thereof are side portions 273 of the bonnet 6. It has the structure made to adjoin with an inner surface.

  A rectangular frame-shaped frame 226 is erected on the frame plate 233 on the front side of the radiator 235. A frame frame 226, a radiator 235, and a fan shroud 234 are arranged in this order from the front above the axle case connecting portion 12b that bridges the left and right engine frames 14. The frame frame 226 is formed so that the rear surface is covered with the radiator 235, and the front surface and the left and right side surfaces thereof are covered with a mesh plate. In the frame frame 226, an oil cooler, a fuel cooler, and the like are installed in addition to the above intercooler. An air cleaner 221 is disposed above the front surface of the frame frame 226. As a result, the cooling air sucked from the front grille 231 flows toward the frame frame 226 behind the front grille 231, thereby cooling the air cleaner 221 and cooling the intercooler, oil cooler, and fuel cooler in the frame frame 226. To do. In addition, the cooling air from the front reaches the radiator 235 provided on the rear surface of the frame frame 226, thereby enhancing the cooling effect on the cooling water supplied to the diesel engine 5.

  The lower side of the axle case connecting portion 12b is provided with a connecting portion in which the positions of the four corners of the front, rear, left and right are protruded downward. The connecting portion is connected to the front axle case 13, and the front axle case 13 is suspended from the engine frame 14. I support it. The front bumper 12 is installed at a position in contact with the front end surface of the engine frame 14 by being connected to the front surface of the axle case connecting portion 12b. As will be described later, the front bumper 12 and the axle case connecting portion 12b constitute a frame connecting member for installing the engine frame 14.

  The front end sides of the left and right fuselage frames 15 are connected to the rear end sides of the left and right engine frames 14 via spacers 297, and the left and right fuselage frames 15 are arranged so as to sandwich the left and right engine frames 14. Yes. The pair of left and right body frames 15 are connected to the front lower side of the floor plate 40 by support beam frames 236. The connection surface (outer surface) of the support beam frame 236 with the body frame 15 is the same surface as the connection surface (outer surface) of the spacer 297 with the body frame 15. The support beam frame 236 is bolted to the left and right airframe frames 15 to mount the left and right airframe frames 15, and the engine support frame 237 is mounted on the upper surface thereof. The engine support frame 237 has a shape that surrounds the flywheel 26 of the diesel engine 5 together with the support beam frame 236 by fastening the lower end surface of the engine support frame 237 with the upper surface of the support beam frame 236.

  The diesel engine 5 has an engine support in which an engine leg mounting portion (not shown) provided on the lower side of the left and right side surfaces is installed in the middle of the pair of left and right engine frames 14 via an engine leg 238 having a vibration isolating rubber 239. The bracket 298 is connected. In the diesel engine 5, an engine leg mounting portion (not shown) provided on the rear surface is connected to the upper surface of the engine support frame 237 via an engine leg body 240 having a vibration isolation rubber 241.

  The engine legs 238 are bolted to the upper part of the engine support bracket 298 connected to the outside of the midway part of the pair of left and right engine frames 14 with the anti-vibration rubber 239 on the lower side. The diesel engine 5 is sandwiched between the engine frames 14 by a pair of left and right engine legs 238 to support the front side of the diesel engine 5. The rear surface of the diesel engine 5 is connected to the front end sides of the pair of left and right body frames 15 via the support beam frame 236, the engine support frame 237, and the engine legs 240, and the diesel engine 5 is rearward at the front end of the body frame 15 The side is supported. The diesel engine 5 is supported on the traveling machine body 2 by the left and right front vibration isolation rubber 239 and the left and right rear vibration isolation rubber 241.

  A pair of left and right support columns 242 and 243 are erected on the upper surface of the engine support frame 237 so as to sandwich the engine leg 240 from the left and right. Specifically, the left column frame 242 is erected via the support bracket 242a at the left rear position of the engine leg 240, and the right column frame 243 is disposed via the support bracket 243a at the right front position of the engine leg 240. Stand up. The support bracket 242a is installed behind the left edge side of the engine support frame 237, and the support bracket 243a is installed ahead of the right edge side of the engine support frame 237. A bonnet shield plate (shield plate) 244 covering the rear of the bonnet 6 is connected to the pair of left and right support frames 242 and 243 so that the lower edge thereof is separated from the upper surface of the engine leg 240.

  The bonnet shield plate 244 has a bent shape in plan view. That is, the bonnet shield plate 244 includes a rear shield surface (first shield surface) 245 that extends from the outer side (left side) of the left column frame 242 to the right and substantially parallel to the front surface of the windshield 321, and the right side of the rear shield surface 245. Side shield surface (second shield surface) 246 bent toward the front at the edge, and connection surface bent toward the right at the front edge of the side shield surface 245 and connected to the right column frame 243 (Third shield surface) 247. The rear shield surface 245 is connected to the left column frame 242 and has a left edge projecting outward (left side) from the left column frame 242 and is disposed away from the front surface of the windshield 321. The side shield surface 246 is disposed on the right side of the upper surface of the engine leg 240. The connection surface 247 is connected to the right column frame 243 so that the right edge thereof is arranged to coincide with the front surface of the right column frame 243.

  Inside the bonnet 6, a bonnet shield plate 244 is disposed on the back side of the bonnet 6 to cover at least the back surfaces of the exhaust gas purification device 224 and the exhaust pipe 227. The bonnet shield plate 244 has a shape protruding to the left side of the left column frame 242 so as to cover at least the left side (exhaust manifold 204 side) rear surface of the diesel engine 5. The bonnet shield plate 244 covers the entire rear surface of the diesel engine 5 by connecting both edges to a pair of left and right support columns 242 and 243. On the back side of the bonnet 6, an area on the right side of the bonnet shield plate 244 is opened, and a bellows pipe 228 and a part of the tail pipe 229 connected to the exhaust pipe 227 are arranged in the area.

  By covering the back of the hood 6 with the hood shield plate 244, heat in the engine room under the hood 6 is shielded by the hood shield plate 244, and the cabin 7 side is heated by exhaust heat from the engine room. Can be prevented. Therefore, the operator in the cabin 7 can operate comfortably without being affected by the exhaust heat of the diesel engine 5 and the exhaust gas purification device 224. By disposing the bonnet shield plate 244 away from the front surface of the cabin 7, a heat insulating layer is formed between the cabin 7 disposed behind the bonnet 6 and the bonnet shield plate 244.

  Further, the bonnet shield plate 244 is provided with irregularities with a predetermined period on the rear shield surface 245 to block sound generated from the engine room under the bonnet 6. Specifically, the bonnet shield plate 244 is provided with rectangular convex portions 245a protruding rearward on the rear surface of the rear shield surface 245 at predetermined intervals in the vertical direction. By providing unevenness on the hood shield plate 244, noise generated from the diesel engine 5 or the like in the engine room below the bonnet 6 can be attenuated by the unevenness of the hood shield plate 244 to prevent noise propagation into the cabin 7. .

  A pair of left and right beam frames 248 and 249 are installed above the fan shroud 234 and the bonnet shield plate 244, respectively. One end (rear end) of the left beam frame 248 is connected to the left column frame 242 via the rear shield surface 245 of the bonnet shield plate 244. One end (rear end) of the right beam frame 249 shorter than the left beam frame 248 is connected to the right column frame 243 through the connection surface 247 of the bonnet shield plate 244. The other ends (rear ends) of the pair of left and right beam frames 248 and 249 are connected to the upper rear surface of the fan shroud 234 via a connection bracket 234c. Since the fan shroud 234 and the bonnet shield plate 244 that are stably supported by the traveling machine body 2 are erected and connected by a pair of beam frames 248 and 249, these members are integrated into a robust engine room frame body as a whole. Can be configured.

  A heat shield plate 250 having left and right edges fixed to a pair of left and right beam frames 248 and 249 is provided. The heat shield plate 250 has the beam frames 248 and 249 installed so as to cover the rear from the middle part of the beam frames 248 and 249 under the bonnet 6. The heat shield plate 250 is disposed so as to cover the exhaust gas purifying device 224 and the upper part of the exhaust pipe 227 above the diesel engine 5. Since the heat shield plate 250 is fixed so as to bridge the beam frames 248 and 249, the beam frames 248 and 249 are reinforced by the heat shield plate 250, and the engine room frame can be made more robust. Further, by disposing the heat shield plate 250 between the exhaust gas purifying device 224 and the exhaust pipe 227 and the bonnet 6, it is possible to prevent the bonnet 6 from being heated due to exhaust heat from the engine room.

  An exhaust gas purification device 224 mounted on the upper part of the diesel engine 5 is positioned behind the bonnet 6, and a heat shield plate 250 is disposed between the bonnet 6 and the exhaust gas purification device 224. By disposing the heat shield plate 250 on the exhaust gas purification device 224, it is possible to prevent the bonnet 6 from being heated by exhaust heat from the exhaust gas purification device 224 and the diesel engine 5. Further, a space can be formed between the bonnet 6 and the heat shield plate 250 to insulate the engine room below the heat shield plate 250 from the outside air, and the exhaust gas purification device 224 can be operated in a high temperature environment. .

  Further, in addition to the heat shield plate 250, a bonnet shield plate 244 that is disposed on the back side of the bonnet 6 and covers at least the exhaust gas purifying device 224 from the back side is provided. The heat in the engine room under the hood is shielded by the hood shield plate 244 together with the heat shield plate 250, so that the cabin 7 can be prevented from being heated by exhaust heat from the engine room. Further, by providing a gap between the bonnet shield plate 244 and the heat shield plate 250, it is difficult to trap hot air in the engine room under the bonnet 6, and heat damage to the exhaust gas purifying device 224 itself, the bonnet 6 and the like is prevented. Generation can be suppressed.

  A diesel engine 5 mounted on the front of the traveling machine body 2, an exhaust gas purification device 224 disposed on the diesel engine 5 to purify exhaust gas of the diesel engine 5, and a cooling fan 206 for air cooling of the diesel engine 5. Is provided. A cooling fan 206 is disposed on the front side of the diesel engine 5, a fan shroud 234 that covers the cooling fan 206 is fixed to the traveling machine body 2, and the cooling fan 206, the diesel engine 5, and the exhaust gas purification device 224 are covered with the bonnet 6. A bonnet shield plate 244 that covers the back of the diesel engine 5 is disposed on the back of the hood 6, and the bonnet shield plate 244 is fixed to the traveling machine body 2. A pair of left and right beam frames 248 and 249 are installed above the fan shroud 234 and the bonnet shield plate 244, respectively.

  A wiper 251 for removing water droplets on the windshield 321 is pivotally attached to the windshield 321. The wiper 251 has a drive shaft 252 inserted into the cabin 7 through the windshield 321 and rotates around the drive shaft 252. The front of the drive shaft 252 of the wiper 251 is covered with the rear shield surface 245 of the bonnet shield plate 244. That is, the drive shaft 252 of the wiper 251 that wipes off the windshield 321 that covers the front surface of the cabin 7 mounted on the traveling machine body 2 is covered with the rear upper surface of the bonnet 6 when viewed from the front. Thereby, it can suppress that rainwater falls directly on the drive shaft 252 of the wiper 251, and the drive mechanism of the wiper 251, and can improve the beauty | look.

  Further, a through hole 253 is provided in a part of the windshield 321, and the hydraulic pump 254 supported inside the cabin 7 is projected from the through hole 253 to the outside of the cabin 7. The through hole 253 is installed at a position facing the connection surface 247 of the bonnet shield plate 244. Therefore, when the hydraulic pump 254 is disposed so as to protrude from the through hole 253 to the outside of the cabin 7, it is possible to prevent buffering with the bonnet shield plate 244. Further, since the front surface of the hydraulic pump 254 is covered by the bonnet shield plate 244, heating due to heat radiation from the engine room in the bonnet 6 is prevented.

  The bonnet shield plate 244 is provided with a rear shield surface 245 that covers the rear of the exhaust gas purification device 224 serving as a high-temperature heat source, thereby providing an installation space for the exhaust gas purification device 224 and a rear portion of the exhaust pipe 227. By disposing behind the connecting surface 244 to cover, an installation space for the hydraulic pump 254 is provided behind the connecting surface 244. That is, by bending the bonnet shield plate 244 in a crank shape in plan view, a space in which the influence of exhaust heat from the engine room side is reduced can be expanded in front of the cabin 7 (control seat 8). 254 can be optimally arranged.

  A bonnet support bracket 255 is provided on the upper edge of the front surface of the bonnet shield plate 244 in order to turn and support the rear of the bonnet 6. The bonnet support bracket 255 has a shape in which both left and right edges are bent, and is fixed to the rear shield surface 245 and the side shield surface 246 of the bonnet shield plate 244. That is, the bonnet support bracket 255 connects the back surface to the rear shield surface 245 and connects the side surface bent at the right edge side to the side shield surface 246.

  Further, the upper end side of the bonnet support bracket 255 is connected to and supported by the hinge member 263 that is connected to and supported by the rear portion of the bonnet 6. The side shield surface 246 of the bonnet shield plate 244 has a notch 246 a on the upper edge side, and a part of the right side surface of the bonnet support bracket 255 can be accessed from the outside of the bonnet shield plate 244. In the bonnet support bracket 255, a temporary fixing pin 255a for temporarily fixing the hinge member 263 connected to the bonnet 6 is protruded from each of the left and right outer surfaces. The bonnet support bracket 255 includes a nut 255b for connecting the hinge member 263 to a position above the temporary fixing pin 255a on each of the left and right inner surfaces.

  Stretchable gas springs (bonnet dampers) 256 and 256 are disposed on the left and right sides of the heat shield plate 250 below the bonnet 6. One end (rear end) of each of the pair of left and right gas springs 256, 256 is pivotally attached to the rear end side of each of the pair of left and right beam frames 248, 249, and the other end (front end) of each of the gas springs 256, 256 is The bonnet 6 is pivotally attached to the upper inner surface. Therefore, by lifting the front part of the bonnet 6, the bonnet 6 can be opened with the upper end position of the bonnet shield plate 244 as an axis fulcrum, and maintenance work of the diesel engine 5 can be performed.

  As shown in FIGS. 5 to 8, the transmission case 17 includes a front transmission case 112 having a main transmission input shaft 28, a rear transmission case 113 having a rear axle case 19, and a rear transmission case 112. An intermediate case 114 for connecting the front side of the rear transmission case 113 to the side is provided. The rear end portions of the left and right machine body frames 15 are connected to the left and right side surfaces of the intermediate case 114 via the left and right upper and lower machine body connecting shafts 115 and 116. That is, the rear end portions of the left and right airframe frames 15 are connected to the left and right side surfaces of the intermediate case 114 by the two upper airframe connecting shaft bodies 115 and the two lower airframe connecting shaft bodies 116. The mission case 17 is integrally connected to form the rear part of the traveling machine body 2. Further, the front transmission case 112 or the power transmission shaft 29 is disposed between the left and right body frames 15 to configure the traveling machine body 2 so as to protect the front transmission case 112 and the like.

  Further, as shown in FIGS. 5 to 8 and the like, left and right front support bases 96 that support the front side of the cabin 7 and left and right rear support bases 97 that support the rear part of the cabin 7 are provided. A front support 96 is bolted to the front end of the left and right machine frame 15 and the front bottom of the cabin 7 is supported on the upper surface of the front support 96 via a vibration isolating rubber member 98. doing. A rear support 97 is fastened to the middle of the left and right widths of the upper surface of the left and right rear axle cases 19 extending horizontally in the left-right direction, and the cabin 7 is connected to the upper surface of the rear support 97 via a vibration isolating rubber body 99. Anti-vibration support is provided at the rear bottom. Accordingly, the traveling machine body 2 supports the cabin 7 in a vibration-proof manner via the plurality of vibration-proof rubber bodies 98 and 99.

  Further, as shown in FIGS. 5 to 8 and the like, a rear support 97 is disposed on the upper surface side of the rear axle case 19 so that the end face of the cross section sandwiches the rear axle case 19 having a substantially rectangular tube shape. An anti-rest bracket 101 is disposed on the lower surface side, and the rear support 97 and the anti-rest bracket 101 are fastened with bolts 102. Both ends of a steady-state rod body 103 with turnbuckles that can be expanded and contracted are connected to an intermediate portion of the lower link 23 that extends in the front-rear direction and the steady-rest bracket 101 to prevent left-right vibration of the lower link 23. doing.

  Next, the structure of the traveling machine body 2 will be described with reference to FIGS. The traveling machine body 2 is configured by connecting a left and right engine frame (front frame) 14 and a left and right machine frame (rear frame) in the front-rear direction. The front ends of the left and right engine frames 14 are erected by a rectangular metal casting frame connecting member 12 to support the diesel engine 5 on the engine frame 14. Thus, the support structure of the diesel engine 5 can be strengthened by fixing the engine frame 14 that supports the diesel engine 5 with the frame connecting member 12 that is a metal casting. Further, since the frame connecting member 12 is configured as a strength member, the rigidity and support strength of the traveling machine body 2 can be improved.

  As shown in FIGS. 14 to 18, the frame connecting member 12 is configured to be divided into a front part (front bumper part) 12 a and a rear part (axle case connecting part) 12 b in the front-rear direction. The side surface of the axle case connecting portion 12b is bolted to the inner surface of the front end of the engine frame 14 with bolts 12c. The axle case connecting portion 12b has a plurality of bolt holes 12d for fastening bolts 12c on the front and rear sides of the left and right side surfaces. The engine frame 14 has a through hole 14a at a position corresponding to the bolt hole 12d of the axle case connecting portion 12b. Therefore, the left and right engine frames 14 are fastened to the axle case connecting portion 12b by inserting the bolts 12c into the through holes 14a of the engine frame 14 and screwing them into the bolt holes 12d of the axle case connecting portion 12b. The front bumper portion 12a is brought into contact with the front end surface of the axle case connecting portion 12b on which the engine frame 14 is installed, and the front bumper portion 12a is fastened and fixed to the axle case connecting portion 12b.

  The axle case connecting portion 12b is provided with connecting legs 12e having bolt holes 12f on the lower surface on both front and rear sides thereof, and the front and rear support members 13b and 13c of the front axle case 13 are provided on the front and rear connecting legs 12e, respectively. To fix. The front axle case 13 has a main body case 13a sandwiched between front and rear support members 13b and 13c, and the main body case 13a can be swung left and right around the front and rear support members 13b and 13c. The main body case 13a accommodates a front wheel transmission shaft that transmits power from the front wheel drive shaft 31 to the front axle 16 and a front wheel differential gear mechanism (not shown).

  In the front support member 13b, a bolt 13e is inserted into a through hole 13d provided for fastening, and the bolt 13d is screwed into a bolt hole 12f of a front connection leg 12e in the axle case connection part 12b. The axle case connecting portion 12b is fixed to the front lower surface. In the rear support member 13c, a bolt 13e is inserted into a through hole 13d provided for fastening, and the bolt 13e is screwed into a bolt hole 12f of the rear connection leg portion 12e in the axle case connection portion 12b. The axle case connecting portion 12b is fixed to the lower rear surface. The front support member 13b and the rear support member 13c sandwich and support the main body case 13a, so that the main body case 13a can tilt to the left and right with respect to the traveling machine body 2. A front wheel drive shaft 31 is inserted into the rear support member 13c from the rear side.

  The frame connecting member 12 is configured such that a restricting member 12h for restricting the tilting range of the front axle case 13 is detachable on the lower surface of the axle case connecting portion 12b. The axle case connecting portion 12b has restricting leg portions 12g to which restricting members 12h are attached on both the left and right sides of the lower surface. The axle case connecting portion 12b is provided with a regulating leg portion 12g at a position between the front and rear connecting leg portions 12e. That is, the frame connecting member 12 has connecting leg portions (connecting portions) 12e to be connected to the upper surface of the front axle case 13 before and after the lower surface of the axle case connecting portion 12b. It is on the left and right sides of the case connecting portion 12b and between the front and rear axle case connecting portions 12b.

  The restricting member 12h is made of a metal piece and has a through hole 12k into which the bolt 12i is inserted. The axle case connecting portion 12b of the frame connecting member 12 has a bolt hole 12j into which the bolt 12i is screwed on the bottom surface of the regulating leg portion 12g. That is, the bolt 12i passes through the through hole 12k of the restricting member 12h and is screwed into the bolt hole 12j in the restricting leg 12g of the axle case connecting portion 12b, whereby the restricting member 12h is fastened and fixed to the frame connecting member 12. To do.

  As shown in FIG. 19, the restricting member 12 h is disposed at the upper positions on both the left and right sides of the front and rear support members 13 b and 13 c that become the swing shaft of the front axle case 13 by being connected to the bottom surface of the restricting leg portion 12 g. The Therefore, in the front axle case 13, when the main body case 13a swings up and down with the front and rear support members 13a and 13b as the center axis, the upper surface of the main body case 13a comes into contact with the lower surface of the restricting member 12h, so that the tilt range ( Limit swing angle).

  Further, since the restricting member 12h is configured to be detachable with respect to the frame connecting member 12, the swing angle limit range θ of the main body case 13a in the front axle case 13 can be changed by changing the height h of the restricting member 12h. Can be changed. That is, as shown in FIG. 20 (a), when the regulating member 12h having the height h1 is attached to the regulating leg 12g, the range of the swing angle of the main body case 13a is within the limit range θ1, while FIG. ), When the restriction member 12h having a height h2 (h2 <h1) is attached to the restriction leg 12g, the swing angle restriction range θ2 (θ2> θ1) of the main body case 13a is obtained. Therefore, the tilting range according to the specifications of the work vehicle 1 can be set by attaching the regulating member 12h having different heights according to the unevenness and the distance (tread) between the left and right wheels on the field.

  As described above, the front ends of the left and right engine frames (front frames) 14 are constructed by the frame connecting members 12 made of a metal casting having a rectangular shape, and the diesel engine 5 is supported on the front frames 14. And, on the lower surface of the frame connecting member 12, a restricting member 12h for restricting the left / right tilt range in the front axle case (front running portion) 13 is made detachable. The engine support structure can be strengthened by fixing the front axle case 14 that supports the diesel engine 5 with the connecting member 12 that is a metal casting. Moreover, the intensity | strength of the traveling body 2 can be improved because the connection member 12 is comprised as an intensity | strength member. Furthermore, by making the regulating member 12h detachable from the lower surface of the connecting member 12, the swing angle of the front axle case 13 can be regulated according to the work situation.

  Before and after the lower surface of the connecting member 12, a connecting leg portion (connecting portion) 12e to be connected to the upper surface of the front axle case 13 is provided. Between the connecting legs 2e. By connecting and supporting the connecting member 12 having rigidity with the front axle case 13, the strength of the traveling machine body 2 can be improved. By restricting the tilting of the front axle case 13 with the rigid connecting member 12, it is possible to reduce the burden on the traveling machine body 2 during traveling.

  As shown in FIG. 21, the front of the engine output shaft (not shown) protruding from the front side of the diesel engine 5 is connected to the front PTO shaft 501 so that the power of the diesel engine 5 can be transmitted to the front of the tractor 1. . The front PTO shaft 501 extends forward from the diesel engine 5, the front end of the front PTO shaft 501 protrudes from the front of the traveling machine body 2, and the working machine installed on the front side of the tractor 1 is The power of The front PTO shaft 501 is connected to the front end of the engine output shaft located below the frame bottom plate 233 and extends toward the front surface of the frame connecting member 12.

  The frame connecting member 12 includes a recess 502 on the upper surface thereof, and a front PTO shaft 501 is disposed inside the recess 502. That is, the frame connecting member 12 has a recess 502 extending in the front-rear direction on the upper surface of each of the front bumper portion 12a and the axle case connecting portion 12b. The front PTO shaft 501 connected to the front end of the engine output shaft of the diesel engine 5 is disposed below the frame bottom plate 233 so as to pass through the recess 502 of the frame connecting member 12, and protrudes from the entire front bumper 12a. I am letting. By adopting a configuration in which the front PTO shaft can be easily arranged in this way, it is possible to diversify the models of the tractor 1.

  As shown in FIGS. 14 to 17, the engine frame 14 has a plurality of bolt holes into which bolts 233b are screwed in order to fasten the connecting bracket 233a with bolts 233b at positions between the front and rear through holes 14a. 14b. The connection bracket 233a is formed of a plate bent in an L shape, and connects one connection surface to the bottom surface of the frame bottom plate 233 while connecting the other connection surface to the side surface of the engine frame 14. As a result, the frame bottom plate 233 is connected to the left and right engine frames 14 via the connection bracket 233a, and is fixed so that the left and right engine frames 14 are installed above the frame connecting member 12. The bolt hole 14b may be a through hole. When the bolt hole 14b is formed of a through hole, the inserted bolt 233b is fastened with a nut.

  The engine frame 14 includes a plurality of through holes 14c behind the bolt holes 14b. By inserting the bolt 296a into the through hole 14c and fastening the under cover 296, the under cover 296 is fixedly disposed on the rear edge of the frame bottom plate 233 so as to be held between the left and right engine frames 14. At this time, the front edge of the under cover 296 is connected to the rear edge of the frame bottom plate 233.

  The engine frame 14 includes a plurality of bolt holes 14d into which the bolts 298a are screwed so that the engine support bracket 298 is fastened with the bolts 298a at positions behind the through holes 14c. The engine leg 238 is fixed to the upper part of the engine support bracket 298 via a vibration isolating rubber 239 so that the diesel engine 5 is sandwiched between the left and right engine frames 14 and the front side of the diesel engine 5 is supported. The bolt hole 14d may be a through hole. When the bolt hole 14d is formed of a through hole, the inserted bolt 298a is fastened with a nut.

  The engine frame 14 includes a plurality of bolt fastening holes 14e on the rear end side to be fastened to the front end side of the body frame 15 with the bolts 15a. The bolt fastening hole 14e is provided in a region overlapping the front end of the body frame 15, and is configured by a bolt hole or a through hole. When the bolt fastening hole 14e is constituted by a through hole, the inserted bolt 15a is fastened with a nut. That is, in the engine frame 14, bolt fastening holes 14 e are arranged along the outer periphery of the spacer 297 in a region covered with the spacer 297 sandwiched between the body frame 15. Further, the engine frame 14 includes a through hole 14f for inserting a bolt 297a in order to fix the spacer 297 to the engine frame 14. The through hole 14f is disposed at a position surrounded by the bolt fastening hole 14e.

  As shown in FIGS. 14 to 17, 21, and 22, the spacer 297 includes a plurality of through holes 297 b on its outer peripheral side, and both the engine frame 14 and the body frame 15 are connected to the through holes 297 b. A bolt 15a to be connected is inserted. The spacer 297 includes a bolt hole 297c in a region surrounded by the through hole 297b on the outer peripheral side, and the bolt 297a is screwed into the bolt hole 297c from the engine frame 14 side and fixed to the engine frame 14. . That is, the spacer 297 has a through hole 297b at a position corresponding to the bolt fastening hole 14e of the engine frame 14, and has a bolt hole 297c at a position corresponding to the through hole 14f of the engine frame 14.

  As shown in FIGS. 14 to 17, 21, and 22, the front end sides of the left and right fuselage frames 15 are connected to the rear end sides of the left and right engine frames 14 via spacers 297. 15 is arranged so as to sandwich the left and right engine frames 14. The pair of left and right body frames 15 are connected by a support beam frame 236. The connection surface (outer surface) of the support beam frame 236 with the body frame 15 is the same surface as the connection surface (outer surface) of the spacer 297 with the body frame 15. The support beam frame 236 is bolted to the left and right airframe frames 15 to mount the left and right airframe frames 15, and the engine support frame 237 is mounted on the upper surface thereof. The engine support frame 237 has a shape that surrounds the flywheel 26 of the diesel engine 5 together with the support beam frame 236 by fastening the lower end surface of the engine support frame 237 with the upper surface of the support beam frame 236.

  As shown in FIGS. 14 to 16, 21, and 22, the fuselage frame 15 has a through hole 15 b for inserting a bolt 15 a in a region overlapping the rear end of the engine frame 14 on the front end side. Have more than one. Accordingly, the bolt 15a is inserted into the through hole 15b of the body frame 15 and the through hole 297b of the spacer 297 and fastened by the bolt fastening hole 14e of the engine frame 14, so that the body frame 15 is connected to the engine frame via the spacer 297. 14 is connected. By interposing a spacer 297 between the engine frame 14 and the airframe frame 15, the installation width of the left and right engine frames 14 is adjusted to the left and right width of the diesel engine 5, while the installation width of the left and right airframe frames 15 is adjusted to the left and right of the mission case 17. Can be adjusted to the width.

  When connecting the body frame 15 to the engine frame 14, first, the bolt 297 a is inserted into the through hole 14 f of the engine frame 14 and screwed into the bolt 297 c of the spacer 297, and the spacer 297 is fastened to the engine frame 14. Then, the bolt 15 a is inserted into the through hole 15 b of the body frame 15 and the through hole 297 b of the spacer 297 and fastened by the bolt fastening hole 14 e of the engine frame 14, and the body frame 15 is connected to the engine frame 14 via the spacer 297. Connect to. Therefore, since the body frame 15 can be connected in a state where the spacer 297 is assembled to the engine frame 14, the burden on the operator in the assembly work of the traveling body 2 can be reduced.

  Further, as shown in FIGS. 14 to 16, 21, and 22, the fuselage frame 15 is used for inserting a bolt 15 c to be connected to the support beam frame 236 behind the through hole 15 b installation region. There are a plurality of through holes (front through holes) 15d. The support beam frame 236 is provided with a plurality of bolt holes 236a on the outer peripheral sides of the left and right end faces so as to be fastened to the body frame 15 with bolts 15c. Accordingly, the left and right fuselage frames 15 are fastened to the support beam frame 236 by inserting the bolts 15 c into the through holes 15 d of the fuselage frame 15 and screwing them into the bolt holes 236 a of the support beam frame 236. By fastening the fuselage frame 15 to the left and right ends of the support beam frame 236, the front side of the left and right fuselage frame 15 can be fixed with high rigidity by the support beam frame 236. By disposing the support beam frame 236 adjacent to the rear of the engine frame 14, the rear side of the engine frame 14 connected to the front end of the body frame 15 can be fixed with high rigidity.

  The body frame 15 is provided with a plurality of through holes 15e in a position surrounded by the through holes 15d so that bolts 96a to be connected to the front support base 96 are inserted, and rearward of the installation positions of the through holes 15d. In order to insert bolts 96b to be connected to the front support 96, a plurality of bolt holes 15f are provided. The support beam frame 236 includes a bolt hole 236b in which a bolt 96a inserted into the through hole 15e is screwed at a position surrounded by the bolt hole 236a. Therefore, by inserting the bolt 96a into the through hole 15e and screwing it with the bolt hole 236a, and screwing the bolt 96b with the bolt hole 15f, the body frame 15 fixed to both ends of the support beam frame 236 can be The front support 96 can be fixed. Further, the front support 96 is fastened also to the support beam frame 236 that is a high-rigidity member, so that the support rigidity of the cabin 7 by the front support 96 can be increased.

  As shown in FIGS. 14 to 17, 22, and 23, the body frame 15 includes a through hole (rear side through hole) 15 g for inserting the body connection shaft bodies 115 and 116 on the rear end side. ing. That is, the fuselage connecting shafts 115 and 116 are fixed to the left and right side surfaces of the mission case 17 by fixing the fuselage connecting shafts 115 and 116 to the intermediate case 114 of the mission case 17 through the through holes 15 g of the left and right fuselage frames 15. Let Therefore, by adopting a configuration in which the side surface of the mission case 17 receives the inner side surface of the body frame 15, the moment generated on the left and right can be suppressed, and offset in the front-rear direction of the body frame 15 fixed by the mission case 17 can be prevented. Thereby, the distortion in the traveling body 2 can be prevented, and the structure of the traveling body 2 can be stabilized.

  A connection structure between the body frame 15 and the mission case 17 will be described below with reference to FIGS. The intermediate case 114 of the machine body frame 15 is provided with a shaft body fastening hole (connection hole) 17a into which the machine body connection shaft bodies 115 and 116 are inserted. The shaft body fastening hole 17a is constituted by a large-diameter hole 17aa extending (excavated) from the left and right side surfaces into the case, and a small-diameter hole 17ab extending (excavated) further from the center of the bottom surface of the hole 17aa into the case. It is composed of two-stage holes. The opening diameter of the through hole 15g in the machine body frame 15 is larger than the opening diameter of the large diameter hole 17aa in the shaft body fastening hole 17a.

  The machine body connecting shaft 115 (116) includes a bolt 115a (116a) screwed into the small diameter hole 17ab of the shaft body fastening hole 17a, a sleeve 115b (116b) having a through hole in the central region, and a sleeve 115b (116b). ) Through the through hole of the shaft body fastening hole 17a and the guide pin 115c (116c) inserted into the large-diameter hole 17aa and a washer (washer) 115d (116d) pressed by the seating surface of the bolt 115a (116a). It consists of. The sleeve 115b (116b) is inserted into the through hole 15g and fixed to the body frame 15 by welding. The guide pin 115c (116c) and the washer 115d (116d) constitute a connecting pin for inserting the bolt 115a (116a) into the transmission case 17.

  That is, the guide pin 115c (116c) is inserted into the large diameter hole 17aa of the shaft body fastening hole 17a through the hollow portion (through hole) of the sleeve 115b (116b) inserted into the through hole 15g, and the guide pin 115c (116c) is inserted. The bolts 115a (116a) are inserted into the small-diameter holes 17ab of the shaft body fastening holes 17a through the hollow portions and screwed to fix the rear ends of the left and right body frames 15 to the intermediate case 114. At this time, the washer 115d (116d) is disposed between the bolt 115a (116a) and the guide pin 115c (116c), and one end face of the washer 115d (116d) is brought into contact with the seat of the bolt 115a (116a). On the other hand, the other end face of the washer 115d (116d) is brought into contact with the end face of the guide pin 115c (116c) and the sleeve 115b (116b).

  The sleeve 115b (116b) has a configuration in which a large-diameter hollow cylinder and a small-diameter hollow cylinder are arranged in two stages with the hollow portions (through holes) being matched. In the sleeve 115b (116b), the outer diameter of the large diameter portion is larger than the opening diameter of the through hole 15g, the outer diameter of the small diameter portion is equal to the opening diameter of the through hole 15g of the body frame 15, and the hollow portion ( The opening diameter of the through hole) is made equal to the opening diameter of the large diameter hole 17aa in the shaft body fastening hole 17a. In addition, the sleeve 115b (116b) has an insertion depth of the small diameter portion into the machine frame 15 equal to the width of the machine frame 15. Therefore, when the sleeve 115b (116b) is inserted into the through hole 15g and fixed, the stepped portion of the sleeve 115b (116b) contacts the outer surface of the body frame 15, and the end surface (inner side) of the small diameter portion of the sleeve 115b (116b). The end surface) and the inner surface of the body frame 15 are the same surface.

  The guide pin 115c (116c) is formed of a hollow cylinder having a central portion penetrating through, and the outer diameter of the guide pin 115c (116c) is equal to the opening diameter of the large-diameter hole 17aa in the shaft body fastening hole 17a, and the hollow portion (through hole) is opened. The diameter is made equal to the outer diameter of the screw portion of the bolt 115a (116a). The insertion direction length of the guide pin 115c (116c) is equivalent to the value obtained by adding the depth of the large-diameter hole 17aa to the insertion direction length of the sleeve 115b (116b). Therefore, when the guide pin 115c (116c) is inserted into the shaft body fastening hole 17a via the sleeve 115b (116b) inserted into the through hole 15g, one end surface of the guide pin 115c (116c) is connected to the shaft body fastening hole 17a. The other end face of the guide pin 115c (116c) is flush with the end face (outer end face) of the large diameter portion of the sleeve 115b (116b). The washer 115d (116d) is formed in a ring shape with a central portion penetrating, and the opening diameter of the opening is made equal to the outer diameter of the screw portion of the bolt 115a (116a), and the outer diameter is set to the guide pin 115c. (116c) larger than the outer diameter.

  Accordingly, when the bolt 115a (116a) is screwed into the shaft body fastening hole 17a via the washer 115d (116d) and the guide pin 115c (116c), the washer of the bolt 115a (116a) is attached to the washer 115d (116d). Abutting on one end face (outer end face), a pressing force is applied to the washer 115d (116d) along the insertion direction of the bolt 115a (116a). Since the other end surface (inner end surface) of the washer 115d (116d) is in contact with the respective end surfaces of the sleeve 115b (116b) and the guide pin 115c (116c), the pressing force by the bolt 115a (116a) is the washer 115d ( 116d) is applied to the sleeve 115b (116b) and the guide pin 115c (116c), respectively. Therefore, the compression force when the bolt 115a (116a) is fastened to the shaft body fastening hole 17a is transmitted through the sleeve 115b (116b), the guide pin 115c (116c), and the washer 115d (116d), respectively. The fuselage frame 15 is fixed to the transmission case 17 in connection with the connecting portion between the intermediate case 114 and the intermediate case 114.

  The intermediate case 114 of the mission case 17 has a configuration in which the peripheral region (outer peripheral region) around the shaft body fastening hole 17a is raised on both the left and right side surfaces. As a result, when the fuselage frame 15 and the transmission case 17 are connected by the fuselage connecting shaft 115 (116), the left and right side surfaces of the intermediate case 114 are sleeves 115b (116b) in the region around the shaft fastening hole 17a. And the inner surface of the body frame 15 are in contact with each other. That is, since the fuselage frame 15 is sandwiched between the sleeve 115b (116b) and the side surface of the intermediate case 114, the surface pressure for fastening the fuselage frame 15 to the intermediate case 114 can be dispersed, and the strength life of the fixed portion can be increased. It can be maintained for a long time.

  An elastic member (not shown) such as an O-ring is fitted to the small diameter portion end of the sleeve 115b (116b). Also, an elastic member (not shown) such as an O-ring is fitted to the guide pin 115c (116c) at the position of the large diameter portion end portion of the sleeve 115b (116b). When the elastic member is sandwiched between the sleeve 115b (116b) and the intermediate case 114, the elastic member is disposed at a position sandwiched between the sleeve 115b (116b) and the washer 115d (116d), so that the sleeve 115b (116b) and the guide are disposed. The displacement of the pin 115c (116c) is prevented, and loosening of the fastening force of the machine body connecting shaft body 115 (116) is prevented.

  As described above, the rear end of the body frame 15 is a part of the traveling body 2 by fastening the body connection shaft bodies 115 and 116 inserted into the through holes 15 to the intermediate case 114 of the transmission case 17. It connects with the mission case 17 which becomes a highly rigid member. On the other hand, on the front end side of the body frame 15, as described above, the support beam frame 236, which is a highly rigid casting material, is horizontally mounted. Therefore, since the body frame 15 is fixed to the front and rear with high-rigidity parts, the rear rectangular portion of the traveling body 2 constituted by the body frame 15 has a structure that can withstand twisting and distortion in the front-rear direction.

  The engine frame 14 extends forward from the front end of the body frame 15 fixed by the support beam frame 15, and the front end is fixed by the frame connecting member 12 which is a highly rigid casting material. . That is, since the engine frame 14 is fixed to the front and rear with high-rigidity parts, the front rectangular portion of the traveling machine body 2 constituted by the engine frame 14 has a structure that can withstand twisting and distortion in the front-rear direction. Have. Further, the front of the diesel engine 5 is supported by the engine frame 14 that is a part of the front rectangular part of the traveling machine body 2, while the rear of the diesel engine 5 is supported as a part of the rear rectangular part of the traveling machine body 2. It is supported by a beam frame 236. Therefore, even the diesel engine 5 configured to support the exhaust gas purification device 224 that is a heavy object can be distributed and supported before and after the traveling machine body 2.

  As described above, the engine frame 14 and the machine frame 15 that are metal plates constitute the traveling machine body 2, thereby reducing the weight of the vehicle body of the traveling machine body 2 and at the same time, the diesel engine 5 and the cabin that are heavy objects. The rigidity which can fully support 7 is securable. Further, when the diesel engine 15 and the transmission case 17 having different left and right widths are mounted on the traveling machine body 2, it is not necessary to bend one of the frames so that the connection portions of the engine frame 14 and the machine body frame 15 coincide with each other. Therefore, stress concentration in the support structure can be suppressed, and the strength balance of the entire frame constituting the traveling machine body 2 can be adjusted.

  Also, as shown in FIG. 24, a combination of a frame connecting member 12, an engine frame 14, and a machine frame 15 having different dimensions can be used for a plurality of types of machine configurations. At this time, by changing the front part 12a in the frame connecting member 12, it can be configured to match the center of gravity of each model, so that the center of gravity of the work implement can be stabilized. Further, by adopting a configuration in which the frame connecting member 12 is divided into the front and the rear, it is possible to deal with a plurality of types of machine body configurations, and it is possible to share parts as described later. Furthermore, by combining the engine frame 14 and the body frame 15 having different lengths, the body length can be easily changed according to the vehicle type.

  In the engine frame 14 having different lengths, the bolt hole 14b for connecting the frame bottom plate 233 and the through hole 14c for connecting the under cover 296 have the same relative position in the front-rear direction, so The cover 296 can be a common part. Further, in the engine frame 14 having different lengths, the through hole 14a for connecting the axle case connecting portion 12b of the frame connecting member 12 is set at the same position with respect to the front end of the engine frame 14 as the axle case connecting portion 12b. The front axle case 13 can be a common part.

  In addition, the structure of each part in this invention is not limited to embodiment of illustration, A various change is possible in the range which does not deviate from the meaning of this invention.

DESCRIPTION OF SYMBOLS 1 Tractor 2 Traveling machine body 3 Front wheel 4 Rear wheel 5 Engine 6 Bonnet 7 Cabin 10 Step 11 Fuel tank 12 Front bumper (frame connecting member)
13 Front axle case 14 Engine frame 15 Airframe frame 17 Mission case 26 Flywheel 96 Front support base 97 Rear support base 112 Front transmission case 113 Rear transmission case 114 Intermediate case 115 Upper airframe connection shaft body 116 Upper airframe connection shaft body 206 Cooling fan 224 Exhaust gas purification device

Claims (3)

In a work vehicle that includes an engine as a drive source and a traveling unit that is driven based on the power of the engine, and that configures a traveling machine body by connecting the left and right front frames and the left and right rear frames back and forth,
A work vehicle characterized in that a front end of each of the left and right front frames is constructed with a rectangular metal casting connecting member, and the engine is supported on the front frame.   The connecting member is configured to be divided into front and rear, the side surface of the rear part of the connecting member is connected to the inner surface of the front end of the front frame, the front part of the connecting member is connected to the front surface of the rear part, The work vehicle according to claim 1, wherein the front part is replaceable.   The work vehicle according to claim 1, wherein the connecting member is provided with a recess having a groove shape along a front-rear direction at a central position on an upper surface thereof.

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