JP2526129Y2 - 4 cycle vertical shaft engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION a. Industrial Field of the Invention The present invention relates to a 4-cycle vertical shaft engine, and more specifically, an oil supply structure to a hydraulic tappet of a 4-cycle vertical shaft engine that operates a valve via a push rod. It is about.

b. Conventional technology In a four-stroke vertical shaft engine, a camshaft is arranged adjacent to the crankshaft, the intake and exhaust valves are operated via a push rod, and the valve spacing changes due to thermal expansion, friction, etc. In some cases, a hydraulic tappet is used to automatically absorb the pressure.

C. Problems to be Solved by the Invention By the way, in such an engine, since the hydraulic tappet is installed with its axis centered in the horizontal direction, the oil is stopped when the engine is stopped, that is, the oil pump is stopped, and oil is supplied to the hydraulic tappet. If the oil is no longer supplied, there is a risk that oil will be drawn out of the hydraulic tappet. If oil is extracted from the hydraulic tappet, the valve spacing will not be adjusted when the engine is started until the hydraulic tappet is filled with oil again, causing noise, intake and exhaust Timing may be shifted.

Further, in an engine employing a hydraulic tappet, a crankcase has been increased in size to form an oil passage for supplying oil to the hydraulic tappet.

Accordingly, it is an object of the present invention to provide a four-stroke vertical shaft engine having a simple structure, a function of adjusting a valve interval from the start of the engine, and a large crankcase even when an oil passage is formed. .

d. Means for Solving the Problems In the four-stroke vertical shaft engine of the present invention, a crankshaft 1 having a shaft axis disposed in a longitudinal direction, and a crankshaft arranged in a juxtaposition close to the crankshaft and extending in a longitudinal direction. , A hydraulic tappet 10 operated by a cam 8c attached to the camshaft, a tappet guide hole 3c for accommodating the hydraulic tappet, and a crankcase 3 for accommodating these.
In a four-cycle vertical shaft engine provided with a cylinder hole 7 for sliding a piston 6 attached to the crankshaft 1 and an oil pump 14 for supplying oil to the tappet guide hole 3c, the camshaft 8 has An upper passage 22 having a lower end connected to the oil pump 14 and extending to a position higher than the tappet guide hole 3c is provided, and one end of the crankcase 3 communicates with an upper end of the upper passage 22. Are provided with oil passages 24, 25 communicating with the tappet guide holes 3c,
4, 25 were partially formed on the side wall between the tappet guide hole 3c and the cylinder hole 7 of the crankcase 3.

e. Operation In the four-stroke vertical shaft engine of the present invention, oil is once guided upward from the tappet and supplied to each tappet via an oil passage extending downward therefrom.
Therefore, even if the oil pump is stopped with the stop of the engine, the oil accumulates in the oil passage, so that the inside of the tappet is kept full of oil.

Further, since the oil passage for supplying oil to the hydraulic tappet is formed in the excessive strength portion of the crankcase, the crankcase does not increase in size even if the oil passage is formed.

f. Embodiment FIGS. 1 to 4 show a four-cycle vertical shaft engine according to the present invention.

This engine is installed in a vehicle body or the like such that the axis of the crankshaft 1 is oriented vertically as shown in FIG. The crankshaft 1 has its upper end journal 1a
Are supported by the crankcase 3 via the ball bearing 2, and the lower end journal 1 b is supported by the crankcase cover 4. The crankpin of this crankshaft 1
1c, one connecting rod 5 is installed, and the connecting rod 5 extends in the horizontal direction.
Therefore, in this engine, the connecting rod 5 moves on a horizontal plane, and moves the piston 6 in the left-right direction in the cylinder 7 in FIG.

In addition, a camshaft 8 is juxtaposed in the engine close to the crankshaft 1. Camshaft 8
The upper end 8a is directly supported by the crankcase 3 and the lower end 8b is directly supported by the crankcase cover 4.
The camshaft 8 has cams 8c at two locations. These cams 8c drive the intake and exhaust valves 9 shown in FIG. And this cam 8c
The hydraulic tappet 10 is actuated by the crest to open the valve 9 via the push rod 11 and the rocker arm 12 against the urging force of the spring 13. The camshaft 8 has a gear 8d, which meshes with the gear 1d of the crankshaft 1.

An oil pump 14 is provided below the camshaft 8. The shaft 14a of the oil pump 14 is arranged on the same axis as the camshaft 8, and its end is
To the end 8b of the camshaft 8.

Further, the engine includes an oil filter 16. This oil filter 16 is located on the opposite side of the crankshaft 1 with respect to the camshaft 8 as shown in FIG. 2, and is installed on the peripheral surface of the crankcase cover 4 as shown in FIG. ing.

In this engine, as shown in FIG. 2, a carburetor 17 is arranged on the side of the oil filter 16, and an air cleaner 18 is arranged on the upper side.

In this engine, as shown in FIGS. 1 and 3, the lower end bearing portion 4a of the crankshaft 1, the lower end bearing portion 4b of the camshaft 8, and the installation portion 4c of the oil filter 16 in the crankcase cover 4 are provided. An oil passage 19 is formed in a straight line, and the oil passage 2 connects the installation portion 4c of the oil filter 16 and the discharge port 14b of the oil pump 14.
0 is formed parallel to the oil passage 19. Therefore, the oil discharged from the oil pump 14 is guided to the oil filter 16 through the passage 20 and is purified by the oil filter 16, and then supplied to the lower end bearing portion 4b of the camshaft 8 through the passage 19, and Bearing of shaft 1
Supplied to 4a.

The crankshaft 1 has an oil passage 21 extending from the lower end 1b of the crankshaft 1c to the circumferential surface of the crankpin 1c.
22 are formed. The oil passage 21 and the upward passage 22 are connected to the oil passage 19 by bearings 4a and 4b of the crankshaft 1 and the camshaft 8, respectively.

An oil passage 23 is formed in the crankcase 3 to connect the upper end bearing 3a of the camshaft 8 and the holding portion 3b of the ball bearing 2 for holding the upper end journal 1a of the crankshaft 1. One end of 23 is connected to the upward passage 2 through a branch passage 22a formed in the camshaft 8.
The other end is open to the side surface of the ball bearing 2. Further, an oil passage 24 is formed inside the upper wall of the crankcase 3. One end of the oil passage 24 communicates with the upper end of the upward passage 22, and the other end communicates with the oil passage 25. The oil passage 25 has tappet guide holes 3c, 3c for accommodating the hydraulic tappet 10, as shown in FIG.
Provided on a side wall provided between the cylinder 7 and
As shown in the figure, through a part of the guide holes 3C, 3c,
It is closed below. The oil passage 24 and the oil passage 25 communicate with the upward passage 22 and the tappet guide hole 3c as one continuous oil passage.

Therefore, the oil supplied to the lower end bearing portion 4a of the crankshaft 1 through the passage 19 lubricates the bearing portion 4a,
Further, the oil is supplied to the crank pin 1c through the oil passage 21,
Lubricate the bearing 5a of the connecting rod 5. Also,
The oil fed to the lower end bearing portion 4b of the camshaft 8 is
The lubricating portion 4b is lubricated, and is further guided to the upper side of the crankcase 3 through the upward passage 22.
a, lubricate the ball bearing 2 through the oil passage 23,
The other part is supplied to the guide holes 3c, 3c of the tappet 10 via the oil passages 24, 25, and is supplied to the pressure chamber of the hydraulic tappet 10. The tappet 10 employed in this engine is a generally known hydraulic tappet, and the oil is used for automatically absorbing a change in valve interval due to thermal expansion, friction, and the like. In FIG. 3, reference numeral 26 denotes a plug for closing the processing port of the oil passage 24, and in FIGS. 3 and 4, reference numeral 27 denotes a plug for closing the processing port of the oil passage 25. It is.

According to the present embodiment, when the oil pump 14 is operated by starting the engine, oil is once transferred upward from the discharge port 14b through the oil passages 20, 21 and the upward passage 22. Then, the oil is supplied to the hydraulic tappet 10 from an oil passage 24 inclined slightly downward and an oil passage 25 arranged vertically. On the other hand, when the engine is stopped, the supply of oil from the oil pump 14 is stopped. However, since the oil is supplied from a position higher than the guide holes 3c, the oil in the oil passages 24, 25 does not flow backward from the upward passage 22 and escape. This allows the hydraulic tappet 10
When a pressure chamber (not shown) is filled with oil and the engine is started next time, no abnormal noise is generated from the engine and the timing of intake and exhaust is not shifted.

In this embodiment, of the two continuous oil passages 24 and 25 for supplying oil to the hydraulic tappet 10, the oil passage 25 disposed vertically is connected to the tappet guide hole 3 c of the crankcase 3 and the cylinder hole 3 c. 7 is provided on the side wall.
The lower part of the cylinder is a part where the wall is thick despite the fact that the explosion pressure of the engine hardly acts. In this embodiment, since the oil passage 25 is formed in this excessive strength part, the crankcase 3 needs to be enlarged. And an oil passage 25 is formed.

g. Effects of the Invention As described above, in the four-cycle vertical shaft engine according to the present invention, the oil pumped by the oil pump is once guided upward from the tappet, and is supplied to each tappet via an oil passage extending downward therefrom. doing. Therefore, even when the engine is stopped, that is, even when the oil pump is stopped, oil is accumulated in the oil passage, whereby the inside of the tappet is maintained in an oil-filled state, and the valve gap adjusting function is provided even when the engine is restarted. Secured.

Also, in the four-stroke vertical shaft engine of the present invention, the oil passage for supplying oil to each tappet is formed so as to pierce the guide hole of each tappet. Easy.

Since the oil passage is provided by using the excess strength portion, a compact four-cycle vertical shaft engine can be obtained even if an oil passage communicating with the hydraulic tappet is formed.

[Brief description of the drawings]

1 to 4 show a four-cycle vertical shaft engine according to the present invention. FIG. 1 is a cross-sectional view taken along the line II in FIG. 2, FIG. 2 is a partial cross-sectional bottom view of the engine, FIG. 3 is a developed cross-sectional view taken along a plane connecting respective axes of the crankshaft, camshaft, and tappet, and FIG. 4 is a cross-sectional view showing a positional relationship between a tappet guide hole of a crankcase and an oil passage. is there. 1 ... Crankshaft, 1a, 1b ... Shanar, 1c ...
... Crank pin, 1d ... Gear, 2 ... Ball bearing, 3 ... Crank case, 3a ... Cam shaft upper end bearing part, 3b ... Ball bearing holding part, 3c ... Tappet guide hole, 4 ... Crank Case cover, 4a ... Crank shaft lower end bearing portion, 4b ... Cam shaft lower end bearing portion, 4c ... Oil filter installation portion, 5 ... Connecting rod, 5a ... Bearing portion, 8 ... Cam shaft, 8a
…… Top end, 8b …… Bottom end, 8c …… Cam, 8d …… Gear,
10 Tappet, 14 Oil pump, 14a Shaft, 14b Discharge port, 15 Pin, 16 Oil filter, 17 Carburetor, 18 Air cleaner, 19 Oil passage, 20 …… Oil passage, 21 …… Oil passage, 22…
… Upward passage, 22a… branch passage, 24 …… oil passage, 2
5 ... Oil passage, 26,27 ... Embedded.

Claims (1)

(57) [Scope of request for utility model registration] 1. A crankshaft (1) provided with a shaft shaft in a longitudinal direction, and a camshaft (1) provided in parallel with the crankshaft (1) and provided with a shaft shaft in a longitudinal direction. 8) and a hydraulic tappet (10) operated by a cam (8c) mounted on the camshaft (8).
A tappet guide hole (3c) for accommodating the hydraulic tappet (10), and a crankcase (3) for accommodating the tappet guide holes (3c).
A cylinder hole (7) for sliding a piston (6) attached to a crankshaft (1), and an oil pump (14) for supplying oil to the tappet guide hole (3c).
In the four-stroke vertical shaft engine provided with: a lower end of the camshaft (8) is connected to the oil pump (14) and extends upward to a position higher than the tappet guide hole (3c). The crankcase (3) is provided with oil passages (24) and (25) having one end communicating with the upper end of the upward passage (22) and the other end communicating with the tappet guide hole (3c). A four-cycle vertical shaft, wherein a part of the oil passages (24), (25) is formed in a side wall between a tappet guide hole (3c) and a cylinder hole (7) of a crankcase (3). engine.