JPS62157278A - Ignition device of engine - Google Patents

Abstract

PURPOSE:To allow an ignition device to be applied even to an engine having a narrow valve caliper angle by immersing and arranging a casing containing an ignition coil in an oil space formed with a cylinder head and a head cover. CONSTITUTION:A casing main body 42 containing an ignition coil 36 is immersed and arranged in an oil chamber 24 formed with a cylinder head 8 and a head cover 20. Therefore, even if the valve caliper angle is narrow, e.g., about 36 deg., the ignition coil 36 can be arranged between cam shafts 21, 22. A gap between the casing main body 42 and a plug box 38 fitted with an ignition plug 34 is sealed with an O ring 54, and a gap between the casing main body 42 and the head cover 20 is sealed with a seal member 52 to secure the sealing performance of the oil chamber. Accordingly, the ignition coil can be arranged between the cam shafts even in a DOHC engine having a relatively narrow valve caliper angle.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an ignition device for an engine.

(In the ignition system of the conventional twin engine, Utility Model No. 59-165507
As seen in the above publication, there is one in which an ignition coil is provided for each spark plug.

This kind of ignition device is a high-tensile cord.

Since a destroyer is not required, there are advantages such as no loss of ignition energy due to high tension cords or loss of ignition energy due to gab, and it has recently been attracting attention as an ignition device suitable for high-output engines.

However, it is necessary to install the ignition coil near the spark plug, especially in the upper part of the cylinder head.
In an OHC type engine equipped with a regular camshaft, the valve mechanism is arranged around the spark plug, so the g [-
is difficult.

In order to solve this problem, a proposal has been made to form an ignition coil housing space between two camshafts that are spaced apart (see above).
(See Publication No. 165507).

According to this proposal, since the ignition coil can be disposed in a way that it penetrates into the Schillingchen F, it has the advantage that it can be incorporated into the engine body without increasing the external dimensions of the engine body.

(Problem to be solved by the invention) However, in the conventional system, the oil chamber in which the camshaft is housed is divided by a partition wall to form a space for accommodating the ignition coil. This was limited to engines with large valve angles.

By the way, the DOHC type engine is adopted as a high-output engine because of its intake/exhaust boat shape and the advantage that the inclination angle of the valve is high by 11 degrees.

For this reason, it is not preferable to be restricted by the angle between the ignition coils and the ignition coil in order to form a housing space for the ignition coil.

Therefore, an object of the present invention is to provide a D
An object of the present invention is to provide an engine ignition device for an OHC engine, in which an ignition coil can be disposed between camshafts.

(Means and effects for solving the problem) The present invention takes note of the existence of a partition wall that was provided to form an ignition coil in the conventional system, and removes this partition wall to directly install the ignition coil in the oil chamber. This was done with an eye to the fact that by arranging the valve, the angle between the valves can be narrowed by at least the amount of the partition wall.

Specifically, the first feature is that the casing containing the ignition coil is placed immersed in the oil space formed by the cylinder head and the head cover.

This feature allows it to be applied even to engines with narrow valve angles. However, in this case, the sealing performance of the oil chamber becomes a problem.

Therefore, as a second feature, a seal is formed between the plug boss to which the spark plug is attached and the Hokki casing, and between the casing and the head cover.

(Example) Embodiments of the present invention will be described below based on the drawings.

In FIG. 2, reference numeral 1 denotes a DOHC four-valve engine, and the engine 1 is of a so-called serial type, with cylinders 2 arranged in series.

The engine 1 includes a cylinder borehole provided in the cylinder block 4, a piston (not shown) fitted into the cylinder pore 6, and a combustion chamber 10 connected to the cylinder mounted on the top surface of the cylinder block 4 by a cylinder 8. is defined, and the shilling block 4 has an intake bow facing the combustion chamber 10) 1
2 and two exhaust ports 14 are provided, making it a so-called four-valve type engine. Each intake port 12 is provided with an intake valve 16, each exhaust port 14 is provided with an exhaust valve 18, and the intake port 12 is provided with an intake valve 16.
The intake system leading to the air cleaner (not shown) is installed,
The exhaust port 14 is connected to an exhaust pipe (not shown) via an exhaust manifold (not shown), and an exhaust system extending from the exhaust manifold to the exhaust pipe is attached. Note that, in FIG. 1, one intake valve 16 and one exhaust valve 18 are illustrated due to the drawing.

The intake valve 16 and the exhaust valve 118 are opened and closed by two independent camshafts 21 and 22 at known timings in synchronization with the rotation of a crankshaft (not shown). That is, an oil chamber 24 covered with a head cover 20 is defined in the upper part of the cylinder head 8, and the oil chamber 24 is provided with an oil chamber 24 at intervals.
Two camshafts 21 and 22 are provided, with the negative camshaft 21 being used to open and close the intake valve 16, and the other camshaft 22 being used to open and close the exhaust valve 18. In other words, −
camshaft 21 is linked to the intake valve 16 via a swing arm 28, and the other camshaft 22 is linked to the exhaust valve 18 via a swing arm 30, so that the so-called DOH
A C-type valve train is configured. The valve angle, that is, the angle between the extending direction of the intake valve 16 and the extending direction of the Sugi 1 air valve 18 is relatively narrow.
6 degrees is used.

An ignition device 32 is provided between the intake valve 16 and the exhaust valve 18, facing the center of the combustion chamber 10. In the ignition device 30, in addition to the spark plugs 34 arranged facing the center of the combustion chamber 10, an ignition coil 36 is attached to each spark plug 34, and the secondary '+h Q from the ignition coil 36 is It is designed to be supplied directly to each spark plug 32.

That is, the cylinder head 8 has a camshaft 21.
An ignition plaque 34 is housed in a plug post 38 that is open to the oil chamber 24 at the center between the oil chambers 22 and 22 .
This ignition plug 34 is connected to an ignition coil 36 via a connector member 40.

The ignition coil 36 is housed in a casing body 42, and the connector member 40 is integrally formed at the lower end of the casing body 42.
A hole 46 to which an outside line 44 is connected is integrally formed at the upper end of the wire 2.

The casing body 42 has a mounting hole 2 with a head force of <-20.
The socket 46 is directly exposed and immersed in the oil chamber 24 with the socket 46 projecting outward from the oil chamber 24.

A first collar 48 is provided between the casing body 42 and the socket foot 46, and two second collars 42 are provided at intervals between the casing body 42 and the connector member 40. , the first collar 48 and the seat 20 of the hole 20a are attached.
A sealing member 52 is interposed between the hole 20 and the hole 20.
A seal is made, and there is a 0 seal between the second guard 42.42a.
A ring 54 is provided, and the oil chamber 24 and the plug post 38 are sealed by the inner wall of the plug post 38 and the O-ring 54.

In the above configuration, the casing body 42 in which the ignition coil 36 is housed is directly immersed in the oil chamber 24, so even though the valve angle is a relatively narrow angle of 36 degrees, camshaft 2
It becomes possible to arrange the ignition coil 36 between 1.22 and 1.22. Further, in this embodiment, since the O-ring 54 is used to seal the inner wall of the plug post 38, when installing the ignition coil 36, the casing body 4 is simply integrated. The installation is simplified in that the oil chamber 24 can be sealed with the plug post 38 by simply inserting the connector member 40 into the plug post 38. Of course, this configuration also has the advantage that the sealing performance is not impaired even against vibrations.

(Effects of the Invention) As is clear from the above description, according to the present invention, the ignition coil can be disposed between the camshafts even in a DOHC engine with a relatively narrow valve angle. The degree of freedom regarding the inclination angle of the valve can be improved. Due to this, the combustion chamber shape,
While the DOHC engine has the advantage of having a high degree of freedom in the shape of the intake port and exhaust boat, it is possible to eliminate the restrictions caused by disposing the ignition coil between the camshafts.

[Brief explanation of drawings]

Fig. 1 shows a DOHC type engine, and is a sectional view taken along line II in Fig. 2, Fig. 2 is a front view of the engine of the embodiment, and Fig. 3 is a sectional view taken along line III-III in Fig. 2. . 1: DOHC engine 8 cylinder head 20: to 1. To Doka - 21, 22: Camshaft 24 Ni oil chamber 32: Ignition device 36: Ignition coil 38 Nib lug post 52: Seal member 54: 0 ring Fig. 1

Claims (1)

[Claims] (1) In an engine ignition system in which an ignition coil installed for each spark plug is disposed between two camshafts provided at the top of a cylinder head, a casing housing the ignition coil. is disposed so as to be immersed in an oil chamber formed by a cylinder head and a head cover, and is sealed between the casing and the head cover and between the casing and a plug boss provided on the cylinder head. , An engine ignition device characterized by: