JPS6014924Y2 - Internal combustion engine intake pipe - Google Patents

Description

[Detailed explanation of the idea] This invention relates to an improvement in the intake pipe of a small internal combustion engine.

In small internal combustion engines mounted on motorcycles and the like, there are restrictions on the location of the carburetor in relation to the vehicle body, and the intake pipe of the internal combustion engine may become long.

In that case, if the intake hole of the cylinder block is made longer, the cylinder block becomes larger and casting becomes more labor-intensive.

Further, the cylinder block requires processes such as cutting the end face and machining the cylinder hole, making it inconvenient to handle a large block.

Some models shorten the intake hole of the cylinder block and connect it with an intake pipe made of rubber hose, etc. In this case, the cylinder block can be made smaller, but it is also possible to use a separate gasket or joint to connect the intake pipe to the intake hole. , the number of parts increases, the manufacturing cost increases, sealing performance must be maintained, and assembly is labor-intensive.

This invention has been improved in view of these points, and the embodiments of the invention shown in the drawings will be described below.

A circumferential groove 2 is provided near the tip of an intake pipe 1 made of a steel pipe or the like, and is bulged outward by roll forming, etc., and the tip of the intake pipe 1 is press-fitted into the end of the intake hole 4 of the engine 3. .

The intake pipe 1 is bent due to the position of the carburetor 5, and the outlet hole of the carburetor 5 is inserted into the other end of the intake pipe 1 for connection.

The effect will be explained.

When the intake pipe 1 is press-fitted into the end of the intake hole 4 of the engine 3, the intake pipe 1 cannot be press-fitted unless force is applied using a press-fitting press.

If the intake pipe 1 is a straight pipe, the other end may be pressed with a press-fitting press, but if the intake pipe 1 is bent as shown in the figure, no force is applied.

In this case, a U-shaped pushing jig is installed in a press-fitting press, and this pushing jig is fitted so as to touch the circumferential groove 2, and the tip of the intake pipe 1 is press-fitted into the end of the intake hole 4 of the engine 3. be able to.

In this way, even if the intake pipe 1 is bent, the intake pipe 1 can be reliably press-fitted and connected to the end of the intake hole 4 using the circumferential groove 2.

As explained above, in this invention, an outwardly bulging circumferential groove is provided near the tip of the intake pipe made of steel pipe, etc., and the tip of the intake pipe is press-fitted to the end of the engine's intake hole.
By hooking the pressing jig of a press-fit press to the circumferential groove of the intake pipe, even if the intake pipe is bent, it can be reliably press-fitted and connected.

And since the engine intake holes can be shortened, the cylinder block can be made smaller, making it easier to move and cheaper.

Since the tip of the intake pipe is press-fitted into the intake hole, the sealing performance is good, no other fastening parts are required, the number of parts is small, and the cost can be reduced.

[Brief explanation of drawings]

The figure is a longitudinal sectional view showing an embodiment of the present invention. 1... Intake pipe, 2... Circumferential groove, 3...
...Engine, 4...Intake hole.

Claims (1)

[Scope of utility model registration request] An intake pipe for an internal combustion engine, characterized in that an intake pipe made of a steel pipe or the like is provided with a circumferential groove that bulges outward at a location near the tip, and the tip of the intake pipe is press-fitted to the end of an intake hole of an engine.