JPH0425898B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a vertical engine in which a radiator is placed above the engine, and a duct is provided between the radiator and the engine to guide the wind after passing through the radiator to the outside of the engine. The present invention relates to a V-shaft liquid-cooled engine, and particularly to the arrangement structure of an air cleaner and the structure of an intake passage.

(Prior art and its problems) There is no known example of a vertical shaft type engine in which a radiator is mounted directly above the engine. However, as prior art, the patent application filed by the applicant in 1983-
There are 275672.

As mentioned above, in a vertical-axis V-type liquid-cooled engine in which the radiator is placed above the engine and a duct is provided between the radiator and the engine to guide the wind after passing through the radiator to the outside of the engine, the air cleaner is installed, for example, in the duct. If it is placed on the side, the following problems will occur.

(1) The air cleaner protrudes significantly from the engine, making the engine too large.

(2) The amount of overhang from the engine becomes too large, which increases the burden on the carburetor and intake manifold that support the air cleaner, leaving problems with support strength. It is also difficult to elastically support the air cleaner.

(3) The vibration of the air cleaner itself increases.

(4) Easy to suck warm air around the engine.

(5) If the duct is provided as a single unit made of resin, for example, reinforcing ribs are required to reduce chattering noise.

(Objectives of the Invention) The objects of the first, second, and third inventions of the present application are (1) making the engine more compact; (2) making it possible to suck good unwarmed air from the air cleaner; 3) Improving the support strength of the air cleaner.

In addition to the above objects, the second invention also aims to improve the rigidity of the air cleaner and duct, improve airtightness, and reduce chattering noise.

The third invention aims to improve intake efficiency by shortening the intake passage and to simplify the intake piping structure.

(Means for achieving the purpose) In order to achieve the above purpose, the first, second,
In a third aspect of the invention, an air cleaner is provided on the upper surface of the duct, and is also provided at a position substantially directly above the carburetor and adjacent to the radiator.

In addition to the above common configuration, the second invention has the duct divided into upper and lower parts, and the air cleaner divided into upper and lower parts, and the lower half of the air cleaner and the upper half of the duct are integrally molded with resin. are doing.

In addition to the above-described common configuration, the third aspect of the present invention provides an intake passage that connects the air cleaner and the carburetor through the duct, and also forms the intake passage integrally with the duct.

(Embodiment) FIG. 1 shows an example in which a tractor is equipped with a vertical shaft V-type engine to which the first, second, and third inventions are applied. In FIG. 1, an engine 1 is mounted on a front axle bracket 2 of a tractor and housed in a bonnet 3, and includes a crankcase 5, an oil pan 6, a pair of cylinders 7, etc. It has a vertical crankshaft 4. A cooling water reserve tank 8, an oil supply hole 9, and an oil drain 10 are provided on the rear side of the engine 1. A carburetor 12 and a fuel pump 13 are provided on the front side of the engine 1.
An exhaust pipe 15 connected to the cylinder head 17 extends forward and downward, and is connected to a muffler 16 at a lower portion of the bonnet front wall 3a. 7 is a cylinder. The bonnet 3 has cooling air intakes formed, for example, in its top wall and side walls.

A radiator cooling fan 20 is arranged above the engine 1, and the fan 20 is fixed to a flywheel 30 via an extension bracket 29. A shroud 21 is arranged around the fan 20, and a duct 22 is arranged below the shroud 21. A radiator 23 is arranged above the fan 20, and the radiator 23 is elastically supported by the crankcase 5 via a suitable bracket and rubber member. The duct 22 is elastically supported on the upper surface of the crankcase 5 via an elastic member such as a rubber material. The duct 22 extends forward, and its front edge is connected to a duct portion 25 of the bonnet 3, and the duct portion 25 is open to the atmosphere through an opening in the front wall 3a of the bonnet. The upper surfaces of the crankcase 5, cylinder 7, etc. are shielded by the duct 22 from the hot air that has passed through the radiator. The duct 22 is molded from resin and is divided into upper and lower parts 22a and 22b, and the shroud 21 is integrally molded into the upper half part 22a. Both the upper and lower portions 22a, 22b are joined at their outer peripheral flange portions to each other by a plurality of bolts (not shown).
In the figure, both cylinders 7 are arranged in a V-shape when viewed from above.

The air cleaner 26 is provided on the upper surface of the front portion of the duct 22, located substantially directly above the carburetor 12, and adjacent to the front edge of the radiator 23. An element 27 is provided inside the air cleaner 26 , and the inner circumferential portion of the element 27 is connected to an intake pipe 30 via an intake passage 28 that vertically penetrates the duct 22 , and the intake pipe 30 is connected to the carburetor 12 . are doing.

In FIG. 3, the air cleaner 26 is divided into an upper half case part 26a and a lower half case part 26b, and the lower half case part 26b is molded with resin integrally with the duct upper half part 22a. A meshing groove 40 is formed on the upper surface of the lower half case portion 26b,
A protrusion 41 is formed on the lower surface of the upper half case part 26a, and the protrusion 41 is engaged with the groove 40, and the upper and lower case parts 26a are connected by bolts 42 and nuts 43 shown in FIG.
a and 26b are joined.

The peripheral wall forming the intake passage 28 in FIG. 3 is divided into two parts: an upper half peripheral wall 32 and a lower half peripheral wall 33.
The upper half circumferential wall 32 is integrally resin-molded with the duct upper half portion 22a, and the lower half circumferential wall 33 is integrally resin-molded with the duct lower half portion 22b. The intake passage 28 is curved toward the front as it goes from the upper end to the lower end.

The intake passage circumferential walls 32 and 33 have a double wall structure, and the upper half circumferential wall 32 has a heat insulating air layer S1 between the double walls in front of the intake passage 28, and the lower half circumferential wall 33 has a double wall structure. A heat insulating air layer S2 between the double walls is formed on the rear side of the double wall. Upper and lower peripheral walls 32, 3
3 are connected by a pair of front and rear bolts 35 and 36. The front bolt 35 is connected to the air layer S1 from above.
The rear bolt 36 is inserted into the air layer S2 from below. By forming the air layers S1 and S2, the air in the intake passage 28 is removed from the duct 2 after passing through the radiator 23.
The influence of hot air inside 2 can be prevented.

In FIGS. 4 and 6, the cross-sectional shape of the outermost peripheral wall portion of each of the peripheral walls 32, 33 is an ellipse that is elongated in the front-rear direction.

FIG. 5 shows a cross section of the upper end portion of the lower half circumferential wall 33. As shown in FIG.

(Function) The air taken in from each cooling air intake of the bonnet 3 passes through the radiator 23 from above to below, cools the liquid in the radiator 23, flows into the duct 22 via the fan 20, and flows into the duct 22. 22
is guided forward and discharged through the duct portion 25 of the bonnet 3. Therefore, the warm air after passing through the radiator does not have much of a thermal effect on the engine and is discharged forward.

(Another Embodiment) The embodiment shown in FIG. 7 is an example in which the intake passage peripheral wall 33 is formed to have a double wall structure over the entire circumference of the intake passage.

(Effect of the invention) As explained above, the first, second, and third inventions of the present application arrange the radiator above the engine,
In a vertical axis V-type liquid-cooled engine that has a duct between the radiator and the engine that guides the air after passing through the radiator to the outside of the engine, an air cleaner is installed on the top of the duct and adjacent to the radiator almost directly above the carburetor. Since all or the essential parts of the structure are arranged in the position where the structure is located, there are the following advantages.

(1) Since the air cleaner is installed on the top of the duct, the air cleaner does not suck in warm air near the engine or warm air after passing through the radiator, and therefore takes in good air that is not warmed up as intake air. I can do it.

(2) The air cleaner no longer protrudes to the side of the engine, making the engine more compact.

(3) Since the air cleaner is generally supported by a duct that is elastically supported by the crankcase, etc., no load is placed on the carburetor or intake manifold, which is advantageous in terms of strength. It also reduces the vibration of the air cleaner itself, improving its durability.

(4) For example, when using the engine as an engine stored in the bonnet of a tractor, the large dead space on the top surface of the duct next to the radiator will be used as the space for installing the air cleaner. Air cleaners with great soundproofing and filtering effects can be installed.

In the second invention, the duct is further divided into upper and lower halves, and the air cleaner is divided into upper and lower halves, and the lower half of the air cleaner and the upper half of the duct are integrally molded with resin.
There are also benefits such as:

(1) A special support member for the air cleaner is no longer required, and the number of parts for the air cleaner can be reduced. It also reduces costs.

(2) The mutual rigidity of the air cleaner case and duct is increased, improving airtightness and reducing chatter noise.

In the third invention, the intake passage that connects the air cleaner and the carburetor is provided through the duct, and the intake passage is integrally molded with the duct, so: (1) The intake passage can be shortened, improving intake efficiency. will improve.

(2) Since there is no need to install a special intake pipe, the structure becomes simpler and the assembly work becomes easier.

(3) Since the intake passage is integrally molded with the duct,
There is no need to worry about hot air inside the duct leaking from the connection between the duct and the intake passage.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of a tractor equipped with a vertical shaft V-type engine to which the first, second, and third inventions of the present application are applied, Fig. 2 is a top view of Fig. 1, and Fig. 3 is a top view of Fig. 1.
The main parts of the figure are enlarged, and the fourth, fifth, and sixth figures are -, -, - cross-sectional views of figure 3, and the seventh figure is an enlarged view of the main part of the figure.
The figure is a horizontal sectional view showing a modified example of the intake passage. DESCRIPTION OF SYMBOLS 1...Engine, 20...Radiator cooling fan, 22...Duct, 22a...Duct upper half part, 22b...Duct lower half part, 26...Air cleaner, 26a...Air cleaner upper half case part, 26b...Air cleaner lower half case part, 28...Intake passage, 32...Upper half peripheral wall, 3
3...Lower half wall.

Claims (1)

[Claims] 1. In a vertical axis V-type liquid-cooled engine in which a radiator is disposed above the engine and a duct is provided between the radiator and the engine to guide the wind after passing through the radiator to the outside of the engine, an air cleaner is installed. A vertical axis V-type liquid-cooled engine, characterized in that it is provided on the upper surface of the duct, and is also provided at a position substantially directly above the carburetor and adjacent to the radiator. 2. In a vertical axis V-type liquid-cooled engine in which the radiator is placed above the engine and a duct is provided between the radiator and the engine to guide the wind after passing through the radiator to the outside of the engine, an air cleaner is provided on the top surface of the duct. At the same time, it is installed at a position almost directly above the carburetor and adjacent to the radiator, and the duct is divided into upper and lower halves, and the air cleaner is divided into upper and lower halves, with the lower half of the air cleaner and the upper half of the duct. A vertical shaft V-type liquid-cooled engine characterized by being integrally molded from resin. 3 In a vertical axis V-type liquid-cooled engine in which the radiator is placed above the engine and a duct is provided between the radiator and the engine to guide the wind after passing through the radiator to the outside of the engine, an air cleaner is provided on the top surface of the duct. In addition, an intake passage is provided at a position substantially directly above the carburetor and adjacent to the radiator, and connects the air cleaner and the carburetor, passing through the duct, and the intake passage is integrally molded with the duct. Vertical axis V type liquid cooled engine. 4. The vertical axis V-type liquid according to claim 3, wherein part or all of the peripheral wall of the intake passage passing through the duct has a double wall structure, and the space between the double walls is a heat insulating air layer. cold engine.