JP4662272B2 - Engine exhaust structure - Google Patents

Description

The present invention relates to an engine exhaust structure applied to Konbai down.

As engine exhaust structure applied to Konbai down to open the distal end portion of the muffler base end portion is fluidly connected to an exhaust port of the engine obliquely downward, a larger diameter than the tip portion of the distal end portion of the muffler In addition, a configuration has been proposed in which a shielding plate having a diameter equal to or larger than that of the upper end portion of the exhaust pipe is provided on the outer periphery of the muffler (see Patent Document 1 below).

  This conventional engine exhaust structure can prevent vibration from being transmitted from the engine to the exhaust pipe because the exhaust pipe is not in contact with the muffler, and can connect the muffler and the exhaust pipe. This is useful in that the exhaust gas in the exhaust pipe can be cooled by the outside air sucked from the portion.

However, since the exhaust pipe located at the downstream side with respect to the flow direction of the exhaust gas has an upwardly connected end portion to the muffler, there is a possibility that unnecessary substances such as mud and soot are mixed in the exhaust pipe.
With respect to this point, in the engine exhaust structure described in Patent Document 1, unwanted matter enters from the upper end of the exhaust pipe by providing the blocking plate that does not form an exhaust gas exhaust passage. It is preventing.
Japanese Utility Model Publication No. 5-69323

  The present invention has been made in view of the above prior art, and cools the exhaust gas and discharges it into the outside air while preventing unwanted substances such as mud and soot from entering the exhaust gas discharge passage of the engine. One object is to provide a simple engine exhaust structure.

In order to achieve the above object, the present invention provides an engine exhaust structure applied to a combine for exhausting exhaust gas from an engine directly or indirectly supported by a traveling machine base to the outside. An upstream exhaust gas flow path forming member whose portion is fluidly connected to the exhaust port of the engine and whose tip is opened in an upward state, and located on the downstream side in the exhaust gas flow direction from the upstream exhaust gas flow path forming member, A downstream exhaust gas flow path forming member opened in a state where the base end portion is downward, the upstream exhaust gas flow path forming member being fluidly connected to the exhaust port of the engine and having a distal end downward A first muffler that is extended, a glen tank and a threshing device that are placed on the traveling machine base such that a base end portion is fluidly connected to a tip end portion of the first muffler and a tip end portion extends rearward. At a position below the lower end of A second muffler that is directly or indirectly supported by the traveling machine base in a state along the longitudinal direction of the vehicle, a base end portion is fluidly connected to a tip end portion of the second muffler, and a tip end portion of the threshing apparatus is A first exhaust pipe opened upward in a position above the frame of the traveling machine base on the rear side of the first conveyor, and the downstream side exhaust gas flow path forming member is opened in a state in which a base end portion faces downward And the second exhaust pipe surrounds the distal end portion of the first exhaust pipe in a state where a gap exists between the proximal end portion and the distal end portion of the first exhaust pipe. it provides an engine exhaust structure according to claim being.

Preferably, the second exhaust pipe, Ru is assumed to AgeKoku conveyor for conveying to the grain tank inherited the best product from the top conveyor extending rearward and upward along the AgeKoku tube was interpolated.

More preferably, a heat insulating cover is extrapolated to at least a part of the second exhaust pipe, and the second exhaust pipe is supported by the cereal cylinder at a portion where the heat insulating cover is extrapolated .

According to the engine exhaust structure of the present invention, the upstream side exhaust gas flow path forming member fluidly connected to the exhaust port of the engine has a base end portion fluidly connected to the exhaust port of the engine and a tip extending downward. A first muffler having a portion, a proximal end fluidly connected to a distal end portion of the first muffler, and a distal end portion positioned behind the proximal end portion and placed on a traveling machine stand And a second muffler that is directly or indirectly supported by the traveling machine stand in a state along the vehicle longitudinal direction at a position below the lower end of the threshing device, and a base end that is fluidly connected to the tip of the second muffler And a first exhaust pipe having a tip portion opened in an upward state at a position above the frame of the traveling machine base on the rear side of the most conveyor in the threshing device, from the upstream side exhaust gas flow path forming member exhaust Downstream exhaust gas flow path forming member positioned in the flow direction downstream side of the scan is provided with a second exhaust pipe having a base end portion which is opened in downward state, the base end portion of the second exhaust pipe is the first Since the front end portion of the first exhaust pipe is surrounded in a state where there is a gap between the front end portion of the one exhaust pipe , the upstream exhaust gas passage formation member and the downstream exhaust gas passage formation member are connection portion from the gap that exists in the connection portion can be sucked outside air, thereby, the things ku comprises members such as shielding closing plate upstream exhaust gas flow path forming member and the downstream exhaust gas flow path forming member the exhaust gas is cooled while effectively preventing the undesired matter such as mud and straw is mixed from can Rukoto.

Further, since the distal end portion of the first exhaust pipe in the upstream exhaust gas flow path forming member is opened upward state position above the traveling machine base frame in the rear side of the top conveyor of thresher unit, the undesired substances such as connecting portions divided et mud and straw of the first and second exhaust pipe can be further effectively prevented from being mixed.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
1 and 2 are a left side view and a plan view of a combine 1 to which an engine exhaust structure according to an embodiment of the present invention is applied, respectively.

  As shown in FIGS. 1 and 2, the combine 1 includes a traveling machine base 2, an engine 9, a crawler-type traveling device 10, a mowing / conveying device 30, a threshing device 100, a driver's seat 5, a glen A tank 6 and a waste disposal device 60 are provided.

Specifically, the engine 9 is supported directly or indirectly by the traveling machine base 2.
The crawler type traveling device 10 is a pair of left and right, and is connected to the traveling machine base 2.
The mowing / conveying device 30 is configured to harvest the cereal and transport the sown culm to the threshing device 100.

The driver's seat 5 is disposed at a right front portion in the traveling direction of the traveling machine base 2. The grain tank 6 is threshed and sorted by the threshing device 100 and concentrated in the first basket 510 (see FIG. 3 to be described later), and further the first conveyor 530 and the cereal conveyor 550 (see FIGS. 5 and 6 to be described later). ) Is stored so as to be stored in the rear X2 of the driver's seat 5.
As shown in FIGS. 1 and 2, the grain stored in the Glen tank 6 inherits the grain from the lower conveyor 6a provided at the bottom of the Glen tank 6 and the lower conveyor 6a. Via a vertical conveyor 6b inserted in the vertical discharge auger 7 so as to be conveyed upward, and a discharge conveyor 6c inserted in the horizontal discharge auger 8 so as to inherit the grains from the vertical conveyor 6b, It is supposed to be discharged.

FIG. 3 is a schematic cross-sectional view showing the threshing apparatus 100, and FIG. 4 is a schematic rear view showing the threshing apparatus 100.
As shown in FIGS. 3 and 4, the threshing device 100 is disposed below the threshing unit 310 that performs a threshing process on the cereals harvested by the harvesting / conveying device 30, and the threshing unit 310. The sorting unit 350 for sorting the grains from the threshing threshed and flowing down by the threshing unit 310, the first thing aggregation mechanism 500, and the second thing re-threshing processing mechanism 600 are provided.

The threshing unit 310 includes a handling chamber 320 defined by a threshing machine frame 321, a handling cylinder 330 that is rotationally driven around a rotation axis along the vehicle front-rear direction (X direction in the drawing) in the handling chamber 320, And a handling cylinder receiving net 340 disposed below the handling cylinder 330.
The treatment barrel 330 has a threshing drive shaft 330a along the vehicle longitudinal direction X and a tooth treatment 331 erected on the outer peripheral surface, and the tooth treatment 331 is accompanied with the rotational drive around the threshing drive shaft 330a. Is rotated, so that the threshing process can be performed on the ear of the cereal that has been cut by the cutting / conveying device 30.
The handling cylinder receiving net 340 is configured to allow only the cereals that have been threshed by the handling cylinder 330 to flow down to the selection unit 350 below the predetermined outer diameter.
Further, the barrel receiving net 340 has a dust feeding port 341 in the vicinity of the rear end portion, and is configured such that large-diameter cereals fall from the dust feeding port 341 to the chaff sheave 420.

  The sorting unit 350 is oscillated by a drive mechanism (not shown) to perform a specific gravity sorting by a swinging sorting mechanism 350A, and sends the sorting wind to the swinging sorting mechanism 350A. And a wind sorting mechanism 350B for discharging outside the machine.

  The swing sorting mechanism 350A includes a pair of left and right swing side plates 351, and a feed pan 410 disposed between the pair of swing side plates 351 so as to receive threshing flowing down from the threshing portion 310. It is arranged between the pair of swinging side plates 351 so as to receive threshing flowing down from the threshing portion 310 and threshing sent from the feed pan 410 and swinging and sorting the grains from the threshing. The chaff sheave mechanism 420 and a stroller mechanism 430 disposed between the pair of swing side plates 351 so as to be arranged in series behind the chaff sheave mechanism 420 X2.

The feed pan 410 is configured to convey the threshing flowing down from the threshing portion 310 in the vehicle width direction (Y direction in the figure) and to convey it toward the chaff sheave mechanism 420 to the vehicle rear X2 side. Yes.
Specifically, the feed pan 410 is a plate body having an upper surface formed in a wave shape.

  The chaff sheave mechanism 420 performs specific gravity sorting on the cereals flowing down from the threshing unit 310 and the cereals sent from the feed pan 410, and a part of the cereals is located on the lowermost side. It is comprised so that 510 may flow down as the first thing.

Specifically, the chaff sheave mechanism 420 is a plurality of fins 421 extending in the vehicle width direction Y between the pair of swing side plates 351, and arranged in parallel in the vehicle longitudinal direction X with a gap therebetween. The fins 421 are provided, and the grains subjected to specific gravity selection are dropped to the first basket 510 arranged below through the interval.
The plurality of fins 421 are swingable integrally around a pivot shaft along the vehicle width direction Y in a rearward inclined state where the lower end portion is positioned closer to the vehicle front X1 side than the upper end portion. In addition, the opening width of the gap can be adjusted by changing the inclination angle by a drive mechanism (not shown).

  The Strollac mechanism 430 performs specific gravity selection on the cereals sent from the chaff sheave mechanism 420 and causes a part of the cereals to flow down as a second item to the second basket 520 located below. In the threshing, large unnecessary items such as waste are conveyed outside the machine.

Specifically, the Strollac mechanism 430 is a plurality of plate-like members 431 extending in the vehicle front-rear direction X in a state where the plate surface is substantially vertical, and are arranged in parallel in the vehicle width direction Y with a space therebetween. A plurality of plate-like members 431, and through the interval, small cereals such as grain with a branch-branch or a grain of ears out of the cereals are used as the second item to the second cocoon 520. It is designed to be dropped.
Each of the plurality of plate-like members 431 has an upper surface formed in a wave shape, thereby promoting the conveyance of a large unnecessary object such as waste to the rear X2.

The wind sorting mechanism 350B is configured to send the sorting wind to the swing sorting mechanism 350A, and the sorting wind can promote the grain sorting by the swing sorting mechanism 350A. Yes.
Specifically, the wind sorting mechanism 350B includes a tang fan 610 that sends the sorting wind that passes from the front lower side to the rear upper side with respect to the swing sorting mechanism 350A.

  The tang fan 610 is configured to be rotationally driven by a tang fan selection drive shaft 610 a along the vehicle width direction Y in front and below the chaff sheave mechanism 420.

Specifically, the tang fan 610 is disposed in a space defined by both side plates 322 (see FIG. 4) of the threshing machine frame and a tang fan case 620 whose rear X2 is opened. The sorting air can be sent out rearward and upward.
More specifically, the tang fan case 620 includes a tang fan case body 621 surrounding the tang fan 610, a front end portion fluidly connected to the tang fan case body 621, and a rear end portion opened obliquely toward the rear X2. And a hollow air passage case 622.
In addition, the side plate 322 of the threshing machine frame is provided with a suction port for sucking air into the tang fan 610.

In the present embodiment, the wind sorting mechanism 350B is further provided with a suction disposed above the swing sorting mechanism 350A so that the sorting wind from the red fan 610 is sucked and discharged to the outside Q. A fan 650 is provided.
The suction fan 650 is rotationally driven by a rotation shaft 650a along the vehicle width direction Y.
More specifically, the suction fan 650 is covered with a suction fan cover 660 having a front opening 661 facing the swing sorting mechanism 350A and a rear opening 662 communicating with the outside Q, and the sorting wind is The air is sucked through the front opening 661 and discharged from the rear opening 662.
Note that both sides of the suction fan 650 are closed by the side wall 322 of the threshing machine frame.

The first object aggregation mechanism 500 includes the first basket 510, the first conveyor 530, the cereal conveyor 550, and the cereal cylinder 560.
The first basket 510 has a concave shape in a side view disposed below the swing sorting mechanism 350A so that the first items sorted by the sorting unit 350 can be collected.

The first conveyor 530 is disposed along the vehicle width direction Y in the most concentrated space. The cereal conveyor 550 inherits the first item from the first conveyor 530 and is inserted into the cereal cylinder 560 (see FIG. 5).
By providing such a configuration, the threshing apparatus 100 allows the first thing collected in the first basket 510 to be accommodated in the Glen tank 6 via the first conveyor 530 and the cereal conveyor 550. It has come to be.

The second thing rethreshing processing mechanism 600 includes the second basket 520, a second conveyor 540, a second reduction conveyor, and a rethreshing processing device (not shown).
The second basket 520 is a side view disposed below the swing sorting mechanism 350A and behind the first basket 510 so as to collect the second products sorted by the sorting unit 350. It is concave.

The second conveyor 540 is disposed along the vehicle width direction Y in the second aggregation space.
By providing such a configuration, the second thing rethreshing processing mechanism 600 is configured such that the second thing collected in the second basket 520 is the downstream end in the conveyance direction of the second conveyor 540 and the second conveyor 540. It is returned to the feed pan 410 via the second reduction conveyor and the threshing processing device inserted in the reduction cylinder in a state of being operatively connected to the section.

Next, the engine exhaust structure according to the embodiment of the present invention will be described in detail.
5 and 6 are diagrams for explaining the engine exhaust structure 70, FIG. 5 is a schematic left side view thereof, and FIG. 6 is a schematic rear view thereof.
The engine exhaust structure 70 shown in FIGS. 5 and 6 is for exhausting the exhaust gas from the engine 9 supported directly or indirectly to the traveling machine base 2 to the outside.
In the present embodiment, the engine exhaust structure 70 includes the engine 9 and the grain tank 6 arranged in series in the vehicle longitudinal direction X on the right side of the traveling machine base 2 with respect to the vehicle forward direction X1. The driver's seat 5 is disposed above the engine 9, the threshing device 100 is disposed on the left side of the traveling machine base 2 (see FIGS. 1 and 2), the Glen tank 6 and the threshing device 100 are disposed. Further, the present invention is applied to the combine 1 in which the waste disposal device 60 including the waste transporting mechanism 40 and the waste cutting mechanism 50 is arranged on the rear side.

In addition, the said waste transporting mechanism 40 is comprised so that the grain waste (waste) after threshing with the said threshing apparatus 100 may be conveyed to back X2, and the said waste cutting mechanism 50 is the said waste cutting mechanism. The waste transported to the vehicle rear side by the transport device 40 is configured to be cut.
By providing such a configuration, the waste disposal device 60 is configured such that the waste after threshing by the threshing device 100 is transported to the waste transporting mechanism 40 and is released to the field as it is, or the waste cutting mechanism. After being cut into pieces at 50, it is configured to be released while being diffused.

In the present embodiment, the waste transport mechanism 40 includes a waste chain 41 so that the waste after being threshed by the threshing device 100 is transported to the rear X2 by the waste chain 41. It has become.
Further, the waste cutting mechanism 50 includes a pair of rotary drums 51 having a rotation axis along the vehicle width direction, and the cutters provided on the respective surfaces of the pair of rotary drums 51 are used to remove the waste filter. The wastes conveyed to the vehicle rear X2 side by the chain 41 can be caught and cut.

The engine exhaust structure 70 includes an upstream exhaust gas flow path forming member 71 and a downstream exhaust gas flow path forming member 72.
The upstream exhaust gas flow path forming member 71 has a base end portion 71a that is fluidly connected to the exhaust port 9a of the engine 9 and a front end portion 71b that is open upward.
The downstream exhaust gas flow path forming member 72 is positioned downstream of the upstream exhaust gas flow path forming member 71 in the flow direction of the exhaust gas, and the base end portion 72a is opened downward.

FIG. 7 is a schematic enlarged cross-sectional view of a connecting portion between a base end portion 72 a of the downstream side exhaust gas flow path forming member 72 and a distal end portion 71 b of the upstream side exhaust gas flow path forming member 71.
As shown in FIG. 7, the downstream exhaust gas flow path forming member 72 has an upstream exhaust gas in a state where a gap S exists between the base end portion 72 a and the distal end portion 71 b of the upstream exhaust gas flow path forming member 71. It is comprised so that the front-end | tip part 71b of the flow-path formation member 71 may be enclosed.
By providing such a configuration, the engine exhaust structure 70 can suck the outside air A from the gap S between the upstream exhaust gas flow path forming member 71 and the downstream exhaust gas flow path forming member 73. In this way, the exhaust gas G is cooled and mud, soot, etc. from the connection part of the upstream exhaust gas flow path forming member 71 and the downstream exhaust gas flow path forming member 72 without providing a member such as a shielding plate. It is possible to effectively prevent the unnecessary matter from being mixed.

Specifically, as shown in FIGS. 5 and 6, the upstream side exhaust gas flow path forming member 71 includes a first muffler 711, a second muffler 712, and a first exhaust pipe 713, and the downstream side The side exhaust gas flow path forming member 72 has a second exhaust pipe 721.

The first muffler 711 has a proximal end portion 71a fluidly connected to the exhaust port 9a of the engine 9 and a distal end portion 711b extending downward.
The second muffler 712 is placed on the traveling machine base 2 such that the base end portion 712a is fluidly connected to the tip end portion 711b of the first muffler 711 and the tip end portion 712b extends rearward X2. It is directly or indirectly supported by the traveling machine base 2 at a position below the lower end of the grain tank 6 and the threshing device 100.

The first exhaust pipe 713 has a proximal end portion 713a fluidly connected to a distal end portion 712b of the second muffler 712 and an open end portion 71b in an upward state.
The second exhaust pipe 721 is opened with a base end portion 72a facing downward, and the base end portion 72a is in a state where a gap S exists between the base end portion 72a and the front end portion 71b of the first exhaust pipe 713. The front end portion 71b of the first exhaust pipe 713 is surrounded.

Specifically, the first exhaust pipe 713 terminates at a position above the frame 21 of the traveling machine base 2 on the rear side of the first conveyor 530 in the threshing device 100.
By providing such a configuration, the engine exhaust structure 70 can prevent the connection portion of the first and second exhaust pipes 713 and 721 from being exposed to the outside in the vehicle width direction Y. It is possible to more effectively prevent the entry of unnecessary substances such as mud and dredging.
In the present embodiment, the first exhaust pipe 713 has a distal end portion 71b located substantially at the center of the traveling machine base 2 in the vehicle width direction Y (see FIG. 6). Accordingly, the connection portion of the first and second exhaust pipes 713 and 721 can be prevented from being exposed to the outside from the traveling machine base 2 with respect to the vehicle width direction Y, whereby the unnecessary matter is mixed from the connection portion. Can be more effectively prevented.

In the engine exhaust structure 70, the first exhaust pipe 713 and the second exhaust pipe 721 constitute an exhaust pipe member 730.
The exhaust pipe member 730 has a proximal end portion 713a fluidly connected to a distal end portion 712b of the second muffler 712 and a distal end portion 721b forming an exhaust outlet P.
The exhaust pipe member 730 has the base 721b opened at a position above the top plate 61 covering the top of the waste disposal device 60 and rearwardly behind the Glen tank 6. It extends rearward and upward from the end 713a.
Further, the distal end portion 721 b of the exhaust pipe member 730 is located below the upper end of the Glen tank 6.
By providing such a configuration, the engine exhaust structure 70 can effectively prevent entry of unwanted materials such as soot and mud from the exhaust outlet P. Further, the exhaust outlet P may be disposed at a position overlapping the grain tank 6 in the vehicle rear view. Thereby, it can prevent effectively that exhaust gas flows into a driver's seat.

In the present embodiment, the exhaust pipe member 730 is disposed between the grain tank 6 and the threshing apparatus 100 in the vehicle width direction Y (see FIG. 6).
In addition, as for the said exhaust pipe member 730, as shown in FIG. 5, it is preferable that the said exhaust outlet P inclines at an angle of about 45 degree | times to back upper direction, for example.

Specifically, the exhaust pipe member 730 includes the first exhaust pipe 713 and the second exhaust pipe 721 as described above.
The first exhaust pipe 713 terminates at a position above the frame 21 of the traveling machine base 2 on the rear side of the first conveyor 530 in the threshing device 100 at the tip end portion 71b.
Further, the second exhaust pipe 721 extends rearward and upward along the cereal cylinder 560 in which the cereal conveyor 550 that inherits the first thing from the first conveyor 530 is inserted.

Further, a heat insulating cover 740 is externally attached to at least a part of the second exhaust pipe 721.
The second exhaust pipe 721 is supported by the milling cylinder 560 at a portion where the heat insulating cover 740 is extrapolated.
By providing such a configuration, the second exhaust pipe 721 can be held in the cereal cylinder 560 without providing a separate holding member. In addition, since the second exhaust pipe 721 is supported by the cereal cylinder 560 via the heat insulating cover 740, heat transfer from the second exhaust pipe 721 to the cereal cylinder 560 can be effectively prevented.

FIG. 1 is a left side view of a combine to which an engine exhaust structure according to an embodiment of the present invention is applied. FIG. 2 is a plan view of the combine shown in FIG. FIG. 3 is a schematic cross-sectional view showing a threshing apparatus. FIG. 4 is a schematic rear view showing the threshing apparatus. FIG. 5 is a schematic left side view for explaining the engine exhaust structure. FIG. 6 is a schematic rear view for explaining the engine exhaust structure. FIG. 7 is a schematic enlarged cross-sectional view of a connection portion between a proximal end portion of a downstream exhaust gas flow path forming member and a distal end portion of an upstream exhaust gas flow path forming member.

DESCRIPTION OF SYMBOLS 1 ... Combine 2 ... Traveling machine stand 9 ... Engine 9a ... Engine exhaust port 5 ... Driver's seat
6 ... Glen tank 21 ... Frame of traveling machine base 40 ... Waste transport mechanism
50 ... Waste cutting mechanism 60 ... Waste treatment device 61 ... Top plate 70 ... Engine exhaust structure
71 ... Upstream exhaust gas flow path forming member
71a ... Base end portion of upstream side exhaust gas flow path forming member (base end portion of first muffler)
71b... Tip portion of upstream side exhaust gas flow path forming member (tip portion of first exhaust pipe)
72 ... Downstream exhaust gas flow path forming member
72a ... Base end portion of the downstream side exhaust gas flow path forming member (base end portion of the second exhaust pipe)
DESCRIPTION OF SYMBOLS 100 ... Threshing apparatus 530 ... First conveyor 550 ... Fleshing conveyor
560 ... Wheat flour mill 711 ... First muffler 711b ... The tip of the first muffler
712 ... Second muffler 712a ... The base end of the second muffler
712b ... the tip of the second muffler 713 ... the first exhaust pipe
713a ... Base end portion of exhaust pipe member (first exhaust pipe) 721 ... Second exhaust pipe
721b ... exhaust pipe member tip 730 ... exhaust pipe member 740 ... heat insulating cover
P ... exhaust outlet S ... gap X ... vehicle longitudinal direction X1 ... vehicle forward direction

Claims (3)

An engine exhaust structure applied to a combine to exhaust exhaust gas from an engine directly or indirectly supported by a traveling machine stand,
An upstream exhaust gas flow path forming member whose base end is fluidly connected to the exhaust port of the engine and whose front end is open in an upward state, and located downstream of the upstream exhaust gas flow path forming member in the exhaust gas flow direction And a downstream exhaust gas flow path forming member whose base end portion is opened in a downward state,
The upstream exhaust gas flow path forming member includes a first muffler having a base end fluidly connected to an exhaust port of the engine and a front end extending downward, and a base end at the front end of the first muffler. Directly connected to the traveling machine base in a state along the longitudinal direction of the vehicle at a position lower than the lower end of the grain tank and the threshing device placed on the traveling machine base so that the tip portion extends rearward. Alternatively, the second muffler supported indirectly and the base end of the second muffler are fluidly connected to the tip of the second muffler, and the tip is above the frame of the traveling machine base on the rear side of the first conveyor in the threshing device. A first exhaust pipe opened in an upward position at a position,
The downstream side exhaust gas flow path forming member has a second exhaust pipe whose base end is opened in a downward state,
The engine exhaust structure according to claim 1, wherein the second exhaust pipe surrounds the distal end portion of the first exhaust pipe in a state where a gap exists between the proximal end portion and the distal end portion of the first exhaust pipe . The second exhaust pipe extends rearward and upward along a cereal cylinder in which a cereal conveyor that inherits the first object from the first conveyor and conveys it to the grain tank is inserted. Item 2. The engine exhaust structure according to Item 1. A heat insulating cover is extrapolated to at least a part of the second exhaust pipe,
The engine exhaust structure according to claim 2, wherein the second exhaust pipe is supported by the cereal cylinder at a portion where the heat insulating cover is extrapolated .

Images