JPH0241350Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention involves fitting an ignition coil into a mounting hole formed on one side of a front cover of a forced air-cooled engine, and placing the ignition coil opposite the magnet of a cooling fan inside the front cover. This invention relates to a mounting device for an ignition coil installed therein.

Generally, the ignition coil of a forced air-cooled engine is disposed so as to face a magnet attached to the side circumference of a cooling fan with a predetermined gap therebetween. The entire ignition coil is disposed in a cooling air flow passage within the fan cover, and is structured so that it can be cooled together with the cylinder, cylinder head, etc. On the other hand, in another structure, the ignition coil is formed with a mounting hole in one side of the front cover that covers the cooling fan corresponding to the fan cover, and is fitted into the mounting hole from the outside, and the ignition coil is inserted into the cooling fan inside. There are some that are placed facing the sky. With this structure, the iron core of the ignition coil is fastened to a boss formed near the mounting hole of the front cover, and
In order to prevent cooling air from flowing out of the gap formed between the mounting hole and the ignition coil, a grommet made of a material such as rubber is tightened together with the bolt to close the gap and seal it.

However, with this type of structure, the grommets are fastened together with bolts, which can cause gaps to form due to deformation of the rubber, allowing cooling air to leak, or causing damage due to the load of the bolts applied to the rubber tightening part. Something happened.

Note that Japanese Utility Model Application Publication No. 59-182628 is a prior art in which an ignition coil is mounted inside a fan cover to ensure sufficient cooling.

This invention was made in view of the above circumstances,
When inserting and installing the ignition coil into the mounting hole formed on one side of the front cover, make sure that the cooling air does not leak out due to the deformation of the grommet caused by tightening the bolts and create a gap, and also prevent the cooling air from leaking into the grommet. To provide an ignition coil mounting device for a forced air-cooled engine that can be easily and reliably mounted without being damaged by load.

In order to achieve the above object, the present invention covers the cooling fan with a front cover, forms a mounting hole and a boss part on one side of the front cover, and provides a mounting hole and a boss part on the side circumference of the cooling fan. An ignition coil for a forced air-cooled engine is provided in which an ignition coil is disposed so as to face a magnet and is fastened to a boss part, and a gap formed between the ignition coil and a mounting hole is covered with a grommet. In the ignition coil mounting device, the ignition coil is mounted by a tightening member formed by extending a holding portion having spring properties that tightly presses and presses the grommet on the outer surface of the ignition coil and the outer surface of the front cover. It is configured to be fastened via an attached washer.

Embodiments of the present invention will be described in detail below with reference to the drawings.

1 to 6 relate to an embodiment of the present invention,
Figure 1 is a front view of the ignition coil mounting part.
Figure 2 is a bottom view of Figure 1, Figure 3 is a front view of the front cover when the ignition coil is not installed, Figure 4 is a bottom view of Figure 3, and Figure 5 is the front cover before assembly. A perspective view of the tightening washer. FIG. 6 is a perspective view of the tightening washer during assembly.

In these figures, reference numeral 1 indicates a cooling fan, 2
is the front cover and the ignition coil 3
is arranged on one side of the front cover 2. The cooling fan 1 is pivotally attached to a crankshaft (not shown), and its periphery is covered with a substantially cylindrical front cover 2. Further, a recess is formed in one outer peripheral portion of the cooling fan 1, and a magnet 4 is disposed in this recess. The ignition coil 3 is composed of a substantially rectangular parallelepiped coil portion 5 and plate-shaped iron core portions 6, 6 disposed on both sides of the coil portion 5. , 6 of the cooling fan 1 are bent somewhat inward and formed into an arc shape so that the end surface portion forms a predetermined gap with the magnet disposed on the outer periphery of the cooling fan. The front cover 2 has a mounting hole 7 for the ignition coil 3 and a boss portion 8 formed in one lower side thereof. The mounting hole 7 includes a rectangular hole in one side of the lower side of the front cover 2, which is large enough to fit the coil part 5, and a square hole large enough to fit the iron core parts 6, which are connected to both ends of this hole. It consists of a rectangular hole. Further, the boss portion 8 connects the mounting hole 7 from one side edge to the iron core portion 6 of the mounting hole 7,
It is formed to protrude downward from the portion where the hole into which the ignition coil 6 is inserted is formed, and screw holes 9, 9 for attaching the ignition coil are formed on the front side of this protrusion. Front cover 2 formed in this way
The ignition coil 3 is inserted into the mounting hole 7 from the outside.
The magnet 4 of the cooling fan 1 and the ends of the iron cores 6, 6 are arranged with a predetermined gap therebetween. After the ignition coil 3 is installed, a gap is formed at the inner peripheral edge of the mounting hole 7, as shown by diagonal lines in FIG. 4, and a grommet 10 is installed to cover this gap. The grommet 10
is made of a material such as rubber, and avoids the outer surface of the coil portion 5 and the bolt tightening portion of the iron core portions 6, 6.
and are in close contact with the outer surfaces excluding the boss portion 8,
Further, it is formed to cover the periphery of the mounting hole 7 from the outside and to be in close contact with the outer surface of the front cover 2. That is, after the ignition coil 3 is disposed in the front cover 2, a gap formed at the inner peripheral edge of the mounting hole 7 is tightly fitted around the coil portion 5, the iron core portion 6, and the mounting hole 7 using the grommet 10. The cooling air inside the front cover 2 is sealed tightly.

Further, the iron core portion 6 of the ignition coil 3,
6 is in contact with the boss portion 8 and is tightened by bolts 11, 11 passing through the iron core portions 6, 6.
It is fastened to the boss portion 8 via 2 and 12. The tightening washer 12 is a plate made of a material such as spring steel, and has a circular tightening portion 14 with a bolt hole 13 in the center, and a circular tightening portion 14 extending in two directions perpendicular to the periphery of the tightening portion 14. Holding portions 5 and 15 are formed.
Then, the washer 12 bends the holding parts 5 and 15 at a substantially right angle, and uses the spring properties of the holding parts 15 and 15 to press the coil part 5 of the grommet 10 and the part of the front cover 2 that are in close contact from the outside. installed to do so.

In the ignition coil mounting device for a forced air-cooled engine configured in this way, the grommet 10
Since the grommet 10 is not directly fastened together with bolts, there is no chance of leakage of cooling air from gaps created by deformation of the rubber of the grommet 10, or damage due to direct application of load from the bolts. In addition, the clamping part 1 is attached to the tightening washer 12.
5, 15 are formed, and these presser parts 5, 15
Due to the springiness of the grommet 10, it is possible to press the grommet 10 into close contact with the coil portion 5 of the ignition coil 3 and the outer peripheral surface of the front cover 2, thereby sealing the cooling air. Furthermore, the holding parts 15, 15 formed in two directions of the tightening washer 12 are arranged so that the grommet 10
Press from the outside to seal the cooling air, and
It also serves to prevent the fastening washer 12 from rotating during installation with bolts, making the installation work easier.

In the above embodiment, the grommet 10 covering the gap formed between the ignition coil 3 and the mounting hole 7 has a complicated shape, but the outer surface of the ignition coil 3 and the outer surface of the front cover 2 are The shape is not limited to that of the embodiment as long as it is formed so as to be in close contact with each other. Further, the tightening washer may be formed so that the holding part presses from the outside of the grommet as the bolt is tightened, so that the ignition coil 3 and the outer surface of the front cover 2 come into close contact with each other, as in the embodiment. The shape does not have to extend in the right angle direction.

Furthermore, the mounting direction of the ignition coil 3 is not limited to the lower side of the front cover, but it can also be mounted in other directions.

As explained above, according to the present invention, in the ignition coil mounting device, the ignition coil is mounted from the outside to one side of the front cover that covers the cooling fan, and the gap is covered with a grommet. Because the grommet is tightened with a bolt through a washer that presses the grommet from the outside and forms a holding part that can be tightly attached to the ignition coil or front cover, it is difficult to tighten the grommet with the bolt as in the past. This eliminates the possibility of leakage of cooling air due to the formation of gaps due to deformation of the rubber parts, or damage caused by loads applied to the rubber tightening parts, allowing for easy and reliable installation.

[Brief explanation of the drawing]

1 to 6 relate to an embodiment of the present invention,
Figure 1 is a front view of the ignition coil mounting part.
Figure 2 is a bottom view of Figure 1, Figure 3 is a front view of the front cover when the ignition coil is not installed, Figure 4 is a bottom view of Figure 3, and Figure 5 is the tightening before assembly. FIG. 6 is a perspective view of the tightening washer during assembly. 1...Cooling fan, 2...Front cover, 3...
...Ignition coil, 4...Magnet, 7
...Mounting hole, 8...Boss portion, 10...Grommet, 12...Tightening washer, 15...Press portion.

Claims (1)

[Scope of utility model registration request] The cooling fan is surrounded by a front cover, a mounting hole and a boss are formed on one side of the front cover, and the ignition coil is inserted into the mounting hole so as to face the magnet provided on the side circumference of the cooling fan. In an ignition coil mounting device for a forced air-cooled engine, which is arranged and fastened to a boss portion, and a gap formed between the ignition coil and the mounting hole is covered with a grommet,
The ignition coil is mounted via a tightening washer formed by extending a presser portion having a spring property that tightly presses and presses the grommet on the outer surface of the ignition coil and the outer surface of the front cover. An ignition coil mounting device for forced air-cooled engines.