JP3835092B2 - Snow vehicle engine equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an engine device for a snow vehicle such as a snowmobile equipped with a four-cycle engine.
[0002]
[Prior art]
A small snow vehicle such as a snowmobile rides over a seat attached to the upper rear side of the frame, and a transmission with a track belt (crawler) housed in the lower rear of the frame is mounted on the front frame. And the vehicle is driven by steering the left and right sleds with the steering wheel.
[0003]
This type of small snow vehicle is generally a two-cycle engine and drives a truck belt. For example, see JP-A-7-125679 and JP-A-9-195762.
[0004]
[Problems to be solved by the invention]
The two-cycle engine is lightweight and has a large output for its compact size, and is used for the power of small snow vehicles. However, compared with a four-cycle engine, noise and vibration are large, the amount of exhaust gas is large, and the used lubricating oil is contained in the exhaust gas, resulting in poor cleanliness.
[0005]
On the other hand, a four-cycle engine has less noise and vibration and a better exhaust gas cleanliness than a two-cycle engine. However, in a four-cycle engine, it is necessary to connect a large cylinder head with an intake / exhaust valve mounted on the cylinder, and it is necessary to connect an oil pan that contains lubricating oil below the crankcase. For this reason, the four-cycle engine has a larger overall height and weight than the two-cycle engine having the same output, which is disadvantageous for weight reduction.
[0006]
In view of the above, the present invention provides a clean snow vehicle engine device that mounts a four-cycle engine by largely tilting a cylinder forward in a front cover of a small snow vehicle, and that is clean and has low noise and vibration. With the goal.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the present invention has the following configuration.
The present invention relates to an engine device for a snow vehicle provided in a space covered with a cover member at the front of a vehicle body, wherein the engine is a four-cycle engine, with a crankshaft directed to the left and right, and a cylinder on the front side. The exhaust pipe is connected to the front side of the engine cylinder head and the intake pipe is connected to the rear side of the engine cylinder head. The intake pipe side is located above the engine and the exhaust pipe side. The lower part of the crankcase is supported by a track belt housing protruding upward at the rear part of the front frame with a bracket in a state of being positioned below, and the upper part of the engine cylinder head above the exhaust hole is provided on the left and right sides of the engine cylinder head. characterized by being supported by a bracket to the front suspension housing formed to project upward at a front portion of the front frame An engine apparatus of the above vehicles.
In the present invention, it is preferable that a clutch device is provided on one side in the crankshaft direction of the engine, a muffler is disposed on the other side in the axial direction, and an exhaust pipe is extended from the lower side to the front side before being connected to the muffler. .
In the present invention, it is preferable that a battery is disposed in a space behind the muffler and outside the brake.
[0008]
In the present invention, the engine is a four-cycle engine, which is advantageous in terms of exhaust gas noise. The four-cycle engine is a cylinder head and the engine is large and the overall height is high, but with the crankshaft facing left and right, the cylinder is tilted forward and mounted on the front frame, making it easy to install, and The air resistance can be reduced by being compactly accommodated in the cover member space covering from above the engine.
And the exhaust pipe is connected to the front side of the engine cylinder head, the intake pipe is connected to the rear side of the engine cylinder head, and the intake pipe side is positioned above the engine, so the carburetor and air cleaner along the engine cylinder Thus, the intake system can be arranged linearly at a high position and the intake air flow becomes smooth.
Further, for the convenience of providing a clutch device on one side in the crankshaft direction of the engine, a muffler is disposed on the other side in the axial direction to effectively use the space in the cover member.
Further, since the exhaust pipe is extended from the lower side of the engine to the front and connected to the muffler, a narrow space can be used more effectively, and the exhaust pipe can be gently bent to improve the exhaust efficiency.
[0009]
Also, the engine can be tilted along the upper surface of the front frame and mounted on the front frame to make it more compact.
In addition, the front side of the engine cylinder head and the lower part of the crankcase are mounted on the front frame via brackets, respectively, so that the engine can be supported from the front and back in the cylinder direction, the weight sharing of the frame can be averaged, and the engine support can be robust. At the same time, the engine vibration can be reduced by pressing the cylinder head.
In addition, the front frame is formed so that the front and rear parts protrude upward from the center part, and the front part protrudes from the front side of the cylinder head of the engine and the rear part protrudes from the lower part of the crankcase via brackets. Install on the front frame. As a result, the engine can be accommodated between the front and rear portions, so that space can be accommodated efficiently. In addition, if a cushion member is interposed in the bracket, the vibration damping effect is greater.
Also, in this case, if the front part protruding above the front frame is a front suspension housing and the rear part protruding upward is a track belt housing, the housing part protruding to accommodate the front suspension and the track belt is effective. In addition, since the protruding housing has higher rigidity than a flat frame, the support rigidity is further increased.
In addition, if batteries are arranged in the space behind the muffler and outside the brake, space utilization efficiency can be improved and wiring can be shortened.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 is an external plan view of a small snow vehicle according to the embodiment, FIG. 2 is an external side view of the small snow vehicle, FIG. 3 is a plan view of an engine in the front of the small snow vehicle, and FIG. 4 is an engine mounted on the small snow vehicle. FIG. 5 is a detailed side view of the engine, FIG. 6 is a front side view of a small snow vehicle showing another embodiment of the engine mounting, and FIG. 7 is a small snow vehicle. FIG. 8 is a detailed plan view of the front frame.
[0011]
The engine device for a small snow vehicle according to the embodiment has the engine 1 mounted in a space (engine room) 25 covered with a vehicle body front cover (also referred to as an engine hood) 15.
In this small snow vehicle, a pair of left and right steering sleds 21 and 21 are rotatably installed at the front lower part of the vehicle body extending in the front-rear direction, and the track belt 6a is circulated at the rear lower part of the vehicle body. A crawler 6 is provided.
The crawler 6 is, for example, a track that wraps around a drive wheel 6b disposed at the front end, a driven wheel 6c disposed at the rear end, a plurality of intermediate wheels 6d, a suspension mechanism 6e, and the wheels 6b to 6d. A belt 6a is provided.
[0012]
A long tandem type seat 22 is attached above the rear part of the vehicle body frame 3, and steps 22 a are provided on both the left and right sides of the seat 22. A steering shaft is erected substantially at the center of the vehicle body between the seat 22 and the front cover 15, and a bar handle 23 is provided at the upper end of the steering shaft so as to be inclined slightly rearward and extend left and right in the horizontal direction. It has been.
A rider who sits across the seat 22 drives the track belt 6a by the driving force of the engine 1 while driving the sled 21 on the front left and right with the bar handle 23 at a substantially central portion of the vehicle body so as to travel on the snow. It has become.
[0013]
A windshield 26 is erected in front of the bar handle 23 and the front cover 15 from the base of the windshield 26 extends forward substantially horizontally in a side view as shown in FIG. It is shaped like an upside-down ship, with an arc that gently descends from nearby. The front cover 15 is appropriately provided with a vent hole at the front as needed (not shown).
[0014]
As shown in FIGS. 3 to 6, the engine 1 mounted on the small snow vehicle is a four-cycle engine, and the crankshaft 2 is installed at the front of the frame 3 in the left-right direction with respect to the vehicle traveling direction. The drive side 5a of the V-belt (4) type continuously variable transmission 5 incorporating the centrifugal clutch device is connected to one end of the crankshaft 2 (in the embodiment, the end facing the left side in the vehicle traveling direction).
The passive side 5b of the continuously variable transmission 5 is configured to transmit a driving force to the track belt 6a via a gear or the like. A brake 8 is attached to the other end of the passive shaft 7 of the continuously variable transmission 5.
[0015]
The engine 1 is of a plurality of cylinders such as three cylinders in which a cylinder 9 is largely inclined (for example, 45 ° or more) and has a cylinder head 10 connected to the upper side (FIG. 6 shows the interior of the engine). ) The cylinder head 10 has an intake manifold (intake pipe) in a higher position on the rear side, with the exhaust pipe 11 connected to the front exhaust hole 10o with the rear side set to the intake hole 10i side and the front side set to the exhaust hole 10o side. 12 are connected.
[0016]
The intake manifold 12 branches and communicates an intake passage from the carburetor 13 to the intake holes of each cylinder, and a box-type air cleaner 14 is connected to the upstream side of the carburetor 13. The intake system from the intake manifold 12 to the carburetor 13 and the air cleaner 14 is connected and disposed so as to extend rearward at a position higher than the upper position of the engine cylinder head 10, as shown in FIGS. Is done. Here, the intake system is disposed in the inner space 25 that is higher on the rear side of the front cover 15 near the base of the windshield 26. Further, the upper end of the engine cylinder head 10 is accommodated in the space 25 without interfering with the front inner side of the front cover 15 that is gently lowered.
[0017]
The exhaust pipe 11 connected to the front side of the cylinder head 10 protrudes short downward toward the lower side of the cylinder head 10, bends and extends forward, and then extends to the side of the engine 1 opposite to the side where the continuously variable transmission 5 is disposed (vehicle). Further bent toward the right side of the advancing direction, bent toward the rear in an L shape near the inner surface of the front cover 15, and extended backward to be connected to the front end of the elliptical middle box-shaped muffler 16. The exhaust outlet side pipe at the rear end of the muffler 16 is open to the front part of the cover of the crawler 6 (corresponding to the rear part 3c of the frame front part 3F). The muffler 16 is installed on the opposite side (the other end side of the crankshaft) of the continuously variable transmission 5 with respect to the engine, and wraps around the crankshaft 2 in a side view. Therefore, in the space 25 in the front cover 15, the continuously variable transmission 5 is disposed on the left side of the engine 1, and the muffler 16 is disposed on the right side of the engine 1 so that the space can be used in a well-balanced and efficient manner. .
[0018]
Here, the frame 3 front portion 3F of the snow vehicle has a front portion 3b protruding upward from the main portion 3a, and the rear end of the main portion 3a rises obliquely rearward and upward from the main portion 3a (continuous to the frame rear portion 3R). The rear part 3c (formed) is continuously integrated. The crankcase and the oil pan 17 at the lower part of the engine 1 are dropped into the main part 3a and mounted on the upper surface of the frame front part 3F with the upper part of the cylinder 9 approaching the front part 3b in a forwardly inclined state. For this reason, the engine 1 is mounted on the front frame 3F so as to be inclined along the front frame 3F.
[0019]
Further, the front side of the cylinder head 10 of the engine 1 and the lower part of the crankcase and the oil pan 17 are mounted on the front part 3F of the frame via brackets 18 (18a, 18b). In this case, the cylinder head 10 of the engine A front part 3b protruding from the front side and a rear part 3c protruding from the lower part of the crankcase 17 are installed on the frame front part 3F via brackets 18a and 18b, respectively.
As shown in detail in FIGS. 4, 7, and 8, the front portion 3 b that protrudes upward from the frame 3 </ b> F is a housing that accommodates the upper portion of the front suspension 27 for supporting the left and right sleds 21. The portion 3c is a housing that accommodates the vicinity of the upper part of the driving wheel 6b of the crawler 6, and the rear portion 3c is continuous with a frame rear portion 3R that extends horizontally in the front-rear direction and also serves as a cover that accommodates the entire crawler 6 downward.
[0020]
The brackets 18a and 18b are formed of appropriate angle brackets provided on the left and right sides of the engine 1, and an impact absorbing material 19 such as a cushion rubber is interposed at a fastening position to the frame 3, Floating support is mounted on the front part 3F of the frame 3.
As described above, the engine 1 can be mounted stably by mounting the front and rear of the engine 1 on the frame 3.
[0021]
Further, the battery 20 is accommodated in the space between the rear side of the muffler 16, the outside of the brake 8, and the inside of the front cover 15, located behind the muffler 16. The battery 20 is close to the engine 1 and can be accommodated in a space efficient manner, and the wiring can be shortened.
The front part 3F of the frame 3 is lowered so that the lower part of the engine 1 can enter, and the mounting part on the front side of the engine 1 also serves as a suspension part of the left and right sleds 21 and is reinforced strongly. .
[0022]
A seat 22 is attached to the rear upper side of the frame 3, and a rider who sits across the seat 22 steers the left and right sleds 21 with the bar handle 23, drives the track belt 6 with the engine 1 and moves on the snow. Run.
In this way, the four-cycle engine type engine 1 can be mounted low in the front cover 15 that has been lowered forward, and a small snow vehicle with low noise and vibration can be achieved.
[0023]
Also, the front side of the cylinder head of the engine 1 and the lower part of the crankcase can be mounted on the frame front part 3F via the brackets 18, respectively, so that the engine 1 can be supported from the front and back in the direction of the cylinder 9 and weight sharing to the frame 3 can be averaged. The engine support can be made robust, and the engine vibration can be reduced by pressing the cylinder head 10.
[0024]
The front portion 3F of the frame has front and rear portions 3b and 3c protruding upward from the central portion 3a. The front portion 3b protrudes from the front side of the cylinder head 10 of the engine 1 and the lower portion of the crankcase and the oil pan 17 Is installed on the front part 3F of the frame via brackets 18a and 18b, respectively. As a result, the engine 1 can be accommodated between the front and rear portions, so that a narrow vehicle body space can be accommodated efficiently. If the cushion member 19 is interposed between the brackets 18 and 18, the vibration damping effect is greater.
Further, in this case, the front portion protruding upward of the frame front portion 3F is a front suspension housing, and the rear portion protruding upward is a track belt 6a housing, so that it protrudes for accommodating the front suspension 27 and the track belt 6a. The housing portion can be used effectively, and the protruding housing has higher rigidity than a flat frame, so that the support rigidity is further increased.
[0025]
Further, if the battery 20 is disposed in the space behind the muffler 16 and outside the brake, the space utilization efficiency is improved and the wiring can be shortened.
[0026]
【The invention's effect】
As described above, since the present invention is configured as described above, the front part of a small snow vehicle is lowered by using a four-cycle engine having a large overall height by directing the crankshaft in the left-right direction and tilting the cylinder forward. An engine can be mounted in the cover by effectively using a narrow body space.
The exhaust pipe is connected to the front side of the cylinder head, and the intake pipe is connected to the rear side, so that the carburetor and the air cooler connected to the intake pipe are accommodated inside the rear side of the front cover. be able to.
Further, since the exhaust pipe is bent to the side of the engine and connected to the muffler on the side of the engine, the maraf can also be stored in the front cover. The battery can also be placed near the engine inside the front cover, and the wiring with the engine can be shortened.
Further, the engine can be mounted on the frame via a bracket on the front side of the cylinder head and on the lower rear side of the crankcase, so that the front and rear of the engine can be stably mounted on the frame.
In this manner, a four-cycle engine can be mounted inside the front cover that is lowered forward and downward, and a small snow vehicle that is clean and has low noise and vibration can be achieved.
[Brief description of the drawings]
FIG. 1 is an external plan view of a small snow vehicle according to an embodiment of the present invention.
FIG. 2 is an external side view of a small snow vehicle.
FIG. 3 is a plan view of an engine in a front portion of a small snow vehicle.
FIG. 4 is a partially cutaway front side view for explaining an engine mounted state of a small snow vehicle.
FIG. 5 is a detailed side view of the engine.
FIG. 6 is a front side view of a small snow vehicle showing another embodiment of engine mounting.
FIG. 7 is a detailed side view of the front part of the frame of the small snow vehicle.
FIG. 8 is a detailed plan view of the front frame.
[Explanation of symbols]
1 Engine 2 Crankshaft 3 Frame 3F, 3R Frame front and frame rear
3a, 3b Projected front and rear part of frame front part 5 Continuously variable transmission 8 Brake 9 Cylinder 10 Cylinder head 11 Exhaust pipe 12 Intake pipe 14 Air cleaner 15 Front cover 16 Muffler 17 Crankcase and oil pan 18 Bracket 20 Battery 27 Front suspension

Claims (3)

In an engine device for a snow vehicle provided in a space covered with a cover member at the front of the vehicle body,
The engine is a four-cycle engine, with the crankshaft directed to the left and right, and the cylinder tilted forward and mounted on the front frame,
With the exhaust pipe connected to the front side of the engine cylinder head and the intake pipe connected to the rear side of the engine cylinder head, with the intake pipe side positioned above the engine and the exhaust pipe side positioned below, A track belt housing that protrudes upward at the rear part of the front frame is supported via brackets, and the upper part of the engine cylinder head above the exhaust hole protrudes upward at the front part of the front frame. An engine device for a snow vehicle, which is supported by a front suspension housing via a bracket .   The clutch device is provided on one side in the crankshaft direction of the engine, a muffler is disposed on the other side in the axial direction, and an exhaust pipe is extended from the lower side to the front side of the engine and then connected to the muffler. Snow vehicle engine equipment. 3. The engine device for a snow vehicle according to claim 2 , wherein a battery is disposed in a space behind the muffler and outside the brake.

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