JPS5823016Y2 - Contact breaker device in engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates primarily to a contact breaker device for an ignition circuit in a small, general-purpose, side-valve type internal combustion engine.

Conventionally, this type of device has generally been equipped with a point cam that is linked to the crankshaft and uses the cam to open and close the point. It is inevitable that it will be expensive.

The purpose of the present invention is to obtain a device that does not have such inconveniences, and is provided in a crankcase 4 housing a crankshaft 1 and a camshaft 3 containing a valve cam 2, which is engaged with the valve cam 2. A shaft hole 9 formed in the side wall 8 of the case 4 is provided.
A movable contact 11 at the tip of the rod 7 and a fixed contact 1 opposite to the movable contact 11 in front of the rod 7 are provided in the small chamber 10 to protrude to the outside through the movable contact 11 at the tip of the rod 7 and face the small chamber 10 formed in advance on the outside.
2 and a capacitor part 14 connected to the fixed contact 12.

The camshaft 3 has two valve drive cams 2, one of which is used for air supply and the other for exhaust, and the follower 5 may be engaged with the protrusion. In the illustrated embodiment, one valve operating cam 2 for operating the intake valve 15 is provided, and the follower 5 is engaged with this.

The follower 5 is connected to the crankcase 4, for example, as shown in the first diagram.
It consists of a tiltable plate-like body whose lower end is supported by a bent part 17 at the tip of a bracket 16 fixed inside, or the can 11 is pivoted at its middle part by a shaft as shown in FIGS. 3 to 6. In the one shown in FIG.
It was designed to fit into the root of and support it from the back with a nut 19.

Further, the spring 6 may be formed of a U-shaped spring plate as shown in the first drawing, or may be formed of a coiled spring. 4
Alternatively, although not shown, it may be provided inside the small chamber 10 described above.

In the drawings, reference numeral 20 indicates a piston, and reference numeral 21 indicates a connecting rod that connects the piston 20 to the above-mentioned crankshaft 1.

Furthermore, as described above, the inside of the small chamber 10 is connected to the inside of the crankcase 4 through the shaft hole 9, and therefore oil is likely to enter through this and act on the point portion 13, so this is prevented. If necessary, a flange 22 is provided near the tip of the rod 7, as shown in the second figure, for example.

To explain its operation, according to the rotation of the camshaft 3, the valve operating cams 2, 2 not only control the opening and closing of the intake valve 15 and the exhaust valve (not shown) as appropriate, but also one of the cams 2, 2 The rod 7 is repeatedly moved forward against the spring 6 via the follower 5, and the contacts 11, 12 and the point 13 on the tip side thereof are thereby repeatedly opened and closed, thereby providing a predetermined disconnection in the ignition circuit. is obtained.

In this way, according to the present invention, the valve drive cam 2 on the camshaft 3
The point part 13 is opened and closed using the valve and the point part 13 is opened and closed, eliminating the need for a separate point cam and reducing the number of parts.
3 and the condenser section 14 are housed in a separate small chamber 10 formed in advance on the outside of the crankcase 4, so that they can be housed in a relatively small volume and are protected from oil and other substances inside the crankcase 4. This has the effect of providing stable operation over a long period of time.

[Brief explanation of the drawing]

Figure 1 is a cutaway side view of an example of an engine equipped with the device of the present invention, Figure 2 is a side view of a modified example of the rond part, and Figures 3 to 6 are side views of modified examples of the follower part. It is. DESCRIPTION OF SYMBOLS 1... Crankshaft, 2... Valve drive cam, 3... Camshaft, 4... Crank case, 5... Follower, 6...
・Spring, 70 Tsudo, 8...Side wall, 9...Shaft hole, 10
...Small chamber, 11°12...Contact, 13...Point part, 14...a capacitor part.

Claims (1)

[Scope of utility model registration request] In a crankcase 4 that accommodates a crankshaft 1 and a camshaft 3 having a valve cam 2, there is a follower 5 that engages with the valve cam 2, and a spring that is pushed by the follower 5 as it tilts. A rod 7 that moves forward against the rod 6 is provided, and the rod 7
is made to protrude outside through a shaft hole 9 formed in the side wall 8 of the case 4 and face into a small chamber 10 formed in advance on the outside, and a movable contact at the tip of the rod 7 is inserted into the small chamber 10. 1
1 and a fixed contact 12 opposite to the point part 13 in front of the point part 13, and a capacitor part 14 connected to the fixed contact 12.