JPS638812Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention relates to a side valve type engine with an improved side valve mechanism.

[Prior art and problems]

Previously, as a side valve type engine
The one described in the No. Publication is known. This side-valve type engine has intake and exhaust valves with a piston-shaped valve body at the tip of a valve stem that reciprocates in a straight line by a cam installed on a camshaft, and the valve body fits into the bottom surface of the cylinder side of the combustion chamber. Since a matching cylinder-shaped valve seat was provided, the combustion chamber extended from directly above the piston to the valve seat, and its large volume made it difficult to obtain a high compression ratio, and the engine was relatively large. There was a problem with becoming. In addition, conventional engines such as the side valve type engine described in Japanese Utility Model Application Publication No. 105707/1980 have communication between the combustion chamber and the intake and exhaust ports through a rotary valve plate that is rotated by the output shaft of the engine. Compared to the former, which was described in Japanese Utility Model Publication No. 52-34495, it is possible to obtain a higher compression ratio by reducing the volume of the combustion chamber, but due to the rotary valve plate, Sucking,
Because the exhaust port was controlled to open and close, the structure was significantly different from that of a normal side-valve type engine, and conventional production equipment could not be used, posing many problems in terms of equipment and manufacturing. This invention was made in view of the above-mentioned circumstances, and it can be done without significantly modifying the conventional production equipment.
It is an object of the present invention to provide a side valve type engine that is easy to manufacture, has a small combustion chamber volume, can obtain a high compression ratio, is small in size, and has a simple structure.

[Means to solve the problem]

In order to achieve this purpose, the side valve type engine of the present invention has intake and exhaust valves with a plate-shaped valve body at the tip of a valve stem that is reciprocated in a straight line by a cam installed on a camshaft, and a cylinder top surface. A combustion chamber is formed inside the combustion chamber surrounded by a cylinder head and a combustion chamber, and one side thereof communicates with the intake and exhaust ports through the plate-shaped valve bodies of the intake and exhaust valves.

【Example】

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. In the figure, reference numeral 1 denotes a cylinder into which a piston 2 is fitted, and a cylinder head 3 is fixed onto this cylinder 1. This cylinder head 3
A combustion chamber 4 is formed in an interior surrounded by a recess formed in a portion facing one side of the piston 2 and the top surface of the cylinder 1. Intake and exhaust ports 5 and 6, which open on one side of the combustion chamber 4, extend into the cylinder 1 from one side of the cylinder head 3, and are opened at the upper part of one side thereof. Parallel to the crankshaft 8 connected to the piston 2 and connecting rod 7,
A plurality of cams 10 are fitted to a camshaft 9 to which driving force is transmitted from a crankshaft 8, and valve stems 1 of intake and exhaust valves 11 and 12, which will be described later, are attached to these cams 10.
1a and 12a are supported through cam followers 13, respectively. The valve stems 11a and 12a of the intake and exhaust valves 11 and 12 are connected to the valve guide 1.
The valve stems 11a and 12a each have a rectangular plate-shaped valve body 1 at their tips.
1b and 12b are fixed to each other. The plate-shaped valve bodies 11b, 12b of the intake and exhaust valves 11, 12 are arranged at a position as close as possible to the outer circumference of the piston 2 on one side of the combustion chamber 4, so that the plate-shaped valve bodies 11b, 12b are slidable. Fitting recesses 15 and 16 are formed on the cylinder 1 side and the cylinder head 3, respectively, and the valve stems 11a and 12a are always pressed against the cam 10 via the cam follower 13 by a valve spring 17. In addition, 18 in the figure is an ignition plug provided in the combustion chamber 4,
19 is a gasket interposed between the cylinder 1 and the cylinder head 3. The side valve type single cylinder engine of the embodiment configured as described above operates in the same manner as a normal four-stroke engine, with the piston 2 performing each stroke and the accompanying rotation of the crankshaft 8 causing the camshaft to move. 9 rotates, the cam 10 sucks through the cam follower 13,
By linearly reciprocating the exhaust valves 11 and 12,
These plate-shaped valve bodies 11b and 12b open and close at appropriate times to communicate and shut off the combustion chamber 4 and the intake and exhaust ports 5 and 6, thereby performing intake and exhaust.

[Effect of the invention] As explained above, the side valve type engine of the present invention has plate-shaped valve bodies 11b and 12b provided at the tips of the intake and exhaust valves 11 and 12, which are open to the combustion chamber 4 and one side thereof. By communicating and blocking the intake and exhaust ports 5 and 6, the combustion chamber 4 may have a volume that extends from the outer periphery of the piston 2 onto the cylinder 1 by a thickness that can withstand the pressure during combustion of the air-fuel mixture. It is smaller than the volume described in the aforementioned Japanese Utility Model Publication No. 52-34495 and can be reduced to almost the same volume as that described in the Japanese Utility Model Publication No. 49-105707, so the compression ratio can be increased to increase the output. can be improved.
Further, according to the present invention, the valve stems 11a, 12a of the intake and exhaust valves 11, 12, the cam follower 13
Since the configuration for linearly reciprocating the intake and exhaust valves 11 and 12 does not change much compared to a normal side valve type engine, conventional production equipment can be used, and problems with equipment and manufacturing can be avoided. Furthermore, the intake and exhaust valves 11 and 12 are plate-shaped valve bodies 11b and 1.
2b, the structure is simpler and easier to process than those with a conventional piston-shaped valve body or rotary valve plate, and it can be installed in a small space. Therefore, the effect that the entire engine can be made smaller can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of the present invention, and FIGS. 2, 3, and 4 are - lines in FIG.
They are sectional views taken along the - line and the - line, respectively. 1...Cylinder, 2...Piston, 3...Cylinder head, 4...Combustion chamber, 5, 6...Suction and exhaust ports, 7...Conrod, 8...Crankshaft,
9...Cam shaft, 10...Cam, 11, 12...
Suction and exhaust valves, 11a, 12a...valve stems,
11b, 12b... Plate valve body, 13... Cam follower, 14... Valve guide, 15, 16... Recess, 17... Valve spring, 18... Spark plug, 19...
Gasket.

Claims (1)

[Scope of utility model registration request] The intake and exhaust valves each have a plate-shaped valve body at the tip of a valve stem that is linearly reciprocated by a cam installed on a camshaft. A side valve type engine characterized by comprising a combustion chamber that communicates with intake and exhaust ports, respectively, through plate-shaped valve bodies of the intake and exhaust valves.