JP2001020735A - Riding work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve mounting/detaching workability for muffler by mounting a muffler directly in a front-high rear-low position at a side of a cylinder head of a compulsory cooling engine. SOLUTION: A muffler M is mounted directly at a side of a cylinder head 31, which is the most recessed portion of an engine E, such that the muffler inclines in front-high rear-low position. Accordingly, space is not required so much for the engine E and the muffler M even when the capacity of the muffler M is increased. Further, cost reduction is achieved by simplifying a mounting structure for the muffler M. Moreover, the engine E and the muffler M are covered with a common air-introducing duct for cooling 19, therefore enabling cooling of not only the engine E but the muffler M as well. Thus, back pressure of exhaust is lowered, improving fuel consumption and silencing effect against exhaust noise. Furthermore, since the muffler M is disposed front-high rear-low and exhaust cooling air is emitted backward, the flow of cooling air in the air-introducing duct for cooling 19 is streamlined. Thus cooling the engine E and muffler M can be performed effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a passenger work vehicle.

[0002]

2. Description of the Related Art Conventionally, a forced air-cooled engine and a muffler, which are enclosed in a wind guide duct, are separately provided on an airframe, and an exhaust port of the engine and a muffler are connected to each other through an exhaust pipe. There is a passenger work vehicle that guides exhaust air from the muffler to muffle the sound.

[0003]

However, since the engine and the muffler are separately provided, their support structure is complicated, and if the engine is elastically supported for vibration isolation, it is possible to use the exhaust pipe. Flexibility is required, which increases costs. Further, although the engine is cooled by the cooling air, the muffler is not cooled, so the back pressure of the exhaust cannot be reduced, and the output and fuel consumption are reduced, and the noise is reduced. Had been reduced.

Therefore, it is conceivable to mount the muffler directly on the engine, cover the engine and the muffler with a common air duct, and cool the muffler. In this case, the engine and the muffler are separated. There is a problem that it is difficult to insert a tool such as a wrench between them because they are too close to each other.

[0005] Further, since the direction in which the cooling exhaust air is blown out after cooling the engine is not specified, the flow of the cooling air inside the air guide duct becomes unreasonable, and the cooling of the engine and the muffler becomes insufficient. There was a problem.

[0006]

Therefore, the present invention is characterized in that a forced air-cooled engine is mounted, and a muffler is mounted directly to the side of a cylinder head of the engine with a front elevation and a low inclination. And a passenger work vehicle.

[0007] The present invention also has the following features.

The engine and the muffler are wrapped in a common cooling air duct, and the cooling air is passed through the cooling air duct in the order of the engine and the muffler. Discharge diagonally rearward and downward.

[0009] A tool insertion hole is formed in the muffler so as to penetrate a middle portion of the muffler.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention are as follows.

[0011] A steering wheel is disposed at the front end of the upper surface of a small passenger work vehicle having a pair of right and left crawlers, a seat is disposed at the center of the upper surface, and a forced air-cooled engine is mounted behind the seat. The output shaft of the engine is connected to the transmission case via a traveling clutch to drive the crawler, and the output shaft is connected to the PTO shaft via a PTO clutch, so that the passenger work vehicle is driven from the PTO shaft. It drives various working machines connected to the.

On the other hand, pipes each having an inner diameter slightly larger than the outer diameter of a box spanner to be described later are penetrated in two directions in the middle of the muffler for silencing the exhaust sound of the engine, so that a tool insertion hole is provided. By using a box spanner inserted through the tool insertion hole, tighten the bolts screwed on both sides of the exhaust port provided on the side of the engine,
The muffler is mounted directly on the engine with the muffler tilted to the front, high and low, simplifying the muffler mounting structure and reducing costs.
The space occupied by the muffler is reduced to facilitate the arrangement of other equipment.

Further, the engine and the muffler are covered by a common air duct, the rear portion of the air duct is bent obliquely rearward and downward, and a cooling exhaust outlet is formed at the rear end. The cooling air from the cooling fan cools the engine,
Next, the muffler is cooled while flowing backward and downward along the outer peripheral surface of the muffler.
The cooling exhaust air is discharged diagonally rearward and downward.

Further, a tail pipe extends obliquely rearward and downward from the rear surface of the muffler, and is positioned in the cooling exhaust air discharged obliquely rearward and downward from the cooling exhaust air discharge port. The discharge direction of the exhaust gas is made substantially coincident with that of the exhaust gas to promote the discharge of the cooling exhaust air by the ejector effect.

[0015]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a passenger work vehicle A according to the present invention. The passenger work vehicle A has a rectangular frame-shaped traveling part frame 1 which is disposed substantially horizontally, and has large front and rear ends. The front and rear rolling wheels 2, 3 having the same diameter are pivotally supported, and the small-diameter intermediate rolling wheels 4, 4, 4 are pivotally supported on the lower left and right intermediate portions of the traveling portion frame 1, respectively. The driving sprocket 5 is supported at the upper rear side, and the front and rear rolling wheels on the left and right sides are respectively supported.
Crawler belts 6 are wound around the outer circumferences of 2, 3, the intermediate rolling wheels 4, 4, 4 and the driving sprocket 5, respectively, to form a pair of right and left crawlers 7.

On the upper surface of the running section frame 1, a round pipe is bent through four columns 8 so as to be substantially rectangular in side view.
A main frame 9 formed in a substantially rectangular frame shape in a plan view is mounted. A steering column 10 is erected on the front end of the main frame 9, and a steering wheel 11 is disposed on an upper surface of the steering column 10. A seat 12 is arranged at a slightly forward portion of the main frame 9, a forced air-cooled engine E is arranged behind the seat 12, and an output shaft 13 of the engine E is connected to a tension clutch 14 in the middle thereof. A transmission mission case 16 disposed between the engine E and the traveling unit frame 1 via a belt transmission mechanism 15, 15 having
It is linked to the O-shaft 17. Further, the hood 18 covers the front, rear, left and right sides and the upper side of the engine E.

In particular, in the present embodiment, the muffler M is mounted directly on the side of the cylinder head 31 which is the most constricted portion of the engine E, with the front and rear inclines.
Is increased so that the space occupied by the engine E and the muffler M does not increase.

Further, the mounting structure of the muffler M is simplified to reduce the cost.

Further, the engine E and the muffler M are covered by a common cooling air duct 19 to cool not only the engine E but also the muffler M and reduce the back pressure of the exhaust gas to reduce the engine E. In addition to improving the output and fuel economy of the vehicle, the noise reduction effect of the exhaust noise is enhanced.

As shown in FIGS. 2 and 3, an exhaust port 20 is formed on the upper left side of the cylinder 31 of the engine E. The diamond-shaped flange 21 is formed at two sharp corners of the diamond-shaped flange 21, and screw holes 23, 23 for screwing the mounting bolts 22 are formed at the two sharp corners.

On the other hand, as shown in FIGS. 4 and 5, the muffler M is formed in a substantially cylindrical shape whose front and rear ends are closed by a front cover 24 and a rear cover 25, respectively. It is attached to the engine E.
An extremely short manifold 26 communicating with the inside of the muffler M is protrudingly provided on the inner surface from the rear, and a flange 27 corresponding to the rhombic flange 21 is provided continuously at an end of the manifold 26 on the engine E side. Through the flange 27 and screw holes 2
By tightening the mounting bolts 22,22 screwed to 3,23,
The muffler M is fixed to the engine E.

In particular, two pipes 28, 28 having an inner diameter slightly larger than an outer diameter of a box spanner to be described later are passed through the main body of the muffler M in the left-right direction, so that tool insertion holes 29, 29 are provided.
And each tool insertion hole 29, 29
The mounting bolts 22, 22 can be tightened by a tool T such as a box spanner inserted through the tool insertion holes 29, 29, located on the virtual extension line 2 of FIG.

As shown in FIGS. 2 and 3, the cooling air guide duct 19 is a crankshaft (not shown) of the engine E.
Of the cooling fan 30 connected to the right end of the
Of the muffler M, and the end of the cooling air guide duct 19 is bent backward from the rear position of the muffler M, and is opened rearward at the rear end. The cooling exhaust air outlet 32 is opened to exhaust the cooling exhaust air to the rear lower direction. In addition, cooling air duct 19
A cooling air suction hole 33 is formed at a position facing the center of the cooling fan 30, and the cooling air sucked from the cooling air suction hole 33 is sent out by the cooling fan 30, and the outer periphery of the cylinder 31 and the muffler M These are cooled in the order of the outer circumference, and are discharged as cooling exhaust air from the cooling exhaust air outlet 32 obliquely rearward and downward. Further, an air scoop 34 opened forward is attached to the cooling air suction hole 33 to prevent the cooling exhaust discharged downward and rearward from being sucked into the cooling air duct 19 again.

Further, the base end of the tail pipe 35 is communicatively connected to the rear end face of the muffler M, and the front end of the tail pipe 35 is
In the above-mentioned cooling exhaust air, it is opened rearward and downward.

Further, since the extremely short manifold 26 is interposed between the cylinder 31 and the muffler M, cooling air is circulated between the two to prevent thermal interference, and the cylinder 31 and the muffler M are separated from each other. It can be cooled effectively.

In the drawing, reference numeral 36 denotes a support for supporting the cooling air guide duct 19 while maintaining a predetermined distance from the muffler M, and 37 denotes a support for detachably attaching the front cover 24 and the rear cover 25 of the muffler M. Bolt, 38 is a crankcase, 39 is a locker room cover, 40
Denotes a starting motor, 41 denotes an oil inlet, and 42 denotes a mounting seat to the machine body.

As described above, since the muffler M is inclined forward and backward and the cooling air is discharged rearward and downward, the flow of the cooling air inside the cooling air duct 19 is streamlined. , Both the engine E and the muffler M can be effectively cooled. Further, by forming the bonnet 18 low, it is possible to improve the visibility in the rearward and downward direction required when various working machines are connected to the rear of the passenger work vehicle A.

FIGS. 6 and 7 show a mounting structure 50 at the rear end of the bonnet 18. A holding spring mounting base 51 is fixed to the lower surface of the rear end of the bonnet 18, and the lower surface of the holding spring mounting base 51 is attached to the lower surface of the holding spring mounting base 51. A holding spring 53 having a substantially C-shape as viewed from the side, which is opened downward and bent at the opening end outward to form the introduction inclined portions 52, 52, is attached via screws 54, 54 to the inside of the holding spring 53. The left and right extending portions of the rear end of the main frame 9 are sandwiched between them. As shown in FIG. 1, the front end of the bonnet 18 is attached to and detached from the locking pin 55 provided on the upper surface of the middle part of the main frame 9 by a locking hook 56 provided on the front end of the bonnet 18, and is turned up and down. The bonnet 18 is freely attached and detachably mounted on the main frame 9 in cooperation with the holding spring 53. In the figure, reference numeral 57 denotes a stopper for holding the main frame 9 at an appropriate position in the holding spring 53.

[0030]

According to the present invention, the following effects can be obtained.

According to the first aspect of the present invention, the engine and the muffler are mounted by mounting the forced air-cooled engine and mounting the muffler directly to the side of the cylinder head of the engine with a front height and a low inclination. The space occupied by the muffler can be reduced, the arrangement of other devices can be rationalized, and the work of attaching and detaching the muffler can be facilitated.

According to the second aspect of the present invention, the engine and the muffler are wrapped in a common cooling air duct, and the cooling air is passed through the cooling air duct in the order of the engine and the muffler. By discharging the exhaust air from the vicinity of the rear of the engine diagonally to the rear and downward, it is possible to cool the exhaust not only in the engine but also in the muffler, reduce the exhaust back pressure, improve the output and efficiency of the engine, and reduce the exhaust noise. This has the effect of reducing

Further, by discharging the cooling exhaust air from the vicinity of the rear part of the engine obliquely rearward and downward, the flow of the cooling air inside the air guide duct can be streamlined, and both the engine and the muffler can be effectively cooled. it can. In addition, the height of the hood that encloses the engine can be reduced to improve the visibility in the rear-downward direction required when various working machines are connected rearward.

According to the third aspect of the present invention, the muffler includes:
By forming a tool insertion hole that penetrates the middle of the muffler, the muffler mounting bolt can be tightened by inserting a tool such as a box spanner into the tool insertion hole when attaching the muffler. Can be

[Brief description of the drawings]

FIG. 1 is a side view of a passenger work vehicle according to the present invention.

FIG. 2 is a partial cross-sectional side view of the engine.

FIG. 3 is a plan view of the engine.

FIG. 4 is a side view of the muffler.

FIG. 5 is a partial cross-sectional plan view of the muffler.

FIG. 6 is a partial cross-sectional side view showing a bonnet mounting structure.

FIG. 7 is a perspective view showing a bonnet mounting structure.

[Explanation of symbols]

 A Passenger car E Engine M Muffler 12 Seat 19 Cooling air duct 29 Tool insertion hole 31 Cylinder head

Continued on the front page (72) Inventor Yuji Inoue 428 Enami, Okayama-shi, Okayama Pref. Inside Sairei Kogyo Co., Ltd. (72) Inventor Tatsuhiro 428 Enami, Okayama-shi, Okayama Pref. 3G004 AA03 CA04 DA12 EA06

Claims (3)

[Claims] An engine (E) of a forced air cooling type is mounted, and a muffler is provided beside a cylinder head (31) of the engine (E).
A passenger work vehicle characterized in that (M) is mounted directly at an angle from front to back and low. 2. The engine (E) and the muffler (M) are covered by a common cooling air guide duct (19), and cooling air is passed through the engine (E) in the cooling air guide duct (19). E), muffler (M)
2. The passenger work vehicle according to claim 1, wherein the cooling air is discharged from the vicinity of the rear portion of the engine (E) obliquely rearward and downward from the rear portion of the engine (E). 3. The passenger work vehicle according to claim 1, wherein the muffler (M) is formed with a tool insertion hole (29) penetrating a middle part of the muffler (M).