JPH029530Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention electromagnetically interconnects multiple unit ignition coils through a common magnetic path in order to cause spark discharge to the spark plugs of each cylinder of a multi-cylinder internal combustion engine without using a power distributor. This invention relates to an integrated ignition coil.

Traditionally, a single ignition coil and a power distributor were combined to distribute power to the spark plugs of each cylinder of a multi-cylinder internal combustion engine, causing spark discharge, but recently advances in electronic advance and electronic intermittent systems have made this possible. As a result, it has come to be used as a simple power distribution mechanism by eliminating the advance part and interrupter provided inside the power distribution device. Additionally, in order to prevent a decrease in output and the generation of noise due to flying sparks between the rotor and the fixed segment, which is the mechanical power distribution mechanism in the power distribution device, the mechanical power distribution mechanism was removed and a non-power distribution system came to be used. Ta.

In this case, generally, an integrated ignition coil is used, which is made up of a plurality of unit ignition coils that are electromagnetically coupled to each other through a common magnetic path, and each unit ignition coil causes spark discharge to occur at two spark plugs at the same time.

Figure 1 shows a conventional centralized ignition coil with two E
The legs 2 and 2', 3 and 3', and 4 and 4' of the shaped iron cores 1 and 1' are butted against each other, and the center legs 2 and 2' are butted against each other, and the left and right side legs 3 and 3', 4 and 4' are connected to the bobbin The primary coil 5- wound above is inserted from each end into a coil assembly fitted into the bobbin of the secondary coil 5-, and arranged to face each other by maintaining a gap in the coil assembly, As a result, the common magnetic path of the central legs 2 and 2' that are butted together, the leg magnetic path 6a that includes the side legs 3 and 3' and faces in a U-shape on one side of the common magnetic path, and the coil assembly 5a. One unit ignition coil A is constituted by a common magnetic path, a leg magnetic path 6b including side legs 4 and 4', and facing in a U-shape on the other side of the common magnetic path, and a coil assembly 5b. Another unit ignition coil B
Configure. Therefore, the beginning of the winding of the primary coil of each unit ignition coil assemblies 5a and 5b is connected to the battery 7.
and connect the winding ends to mechanical or electronic interrupters 8a and 8b, respectively, and coil assembly 5.
The beginning and end of the winding of the secondary coil 5-a of the coil assembly 5-a are connected to the spark plugs 9a, 10a of the two cylinders, and the secondary coil 5- of the coil assembly 5b is connected to the spark plugs 9b, 9b of the other two cylinders. 10b, for example, when the circuit breaker 8a connected to the primary coil of unit ignition coil A is closed, current flows from the battery 7 to the primary coil, and the leg magnetic path 6a including the side legs and the center leg are connected to each other. A loop-shaped magnetic flux φa is formed between the common magnetic paths of 2 and 2', and when the interrupter 8a opens, the magnetic flux φa suddenly disappears, a high voltage is generated in the secondary coil, and the spark plugs 9a and 10a are activated. A spark discharge occurs, igniting the mixture in the two cylinders. but,
In this case, the side legs 4 of the other unit ignition coil B,
If the leg magnetic path including 4' has a much higher magnetic resistance than the common magnetic path formed by the central legs 2 and 2', a loop-like structure will be created between both leg magnetic paths 6a and 6b when the interrupter 8a is closed. The magnetic flux φa′ is not generated, but the central legs 2, 2′
Since the abutting part has a high magnetic path resistance, the above-mentioned magnetic flux φa' is generated between the two leg magnetic paths, and the interrupter 8a
When the unit ignition coil B opens, a high voltage is induced in the secondary coil of the other unit ignition coil B, and in some cases, a problem may occur in which discharge occurs even in the ignition plugs 9b and 10b, which should not be ignited. be.

Therefore, the present invention solves the above-mentioned problem by providing a cut groove along the longitudinal direction of the common magnetic path, thereby eliminating magnetic interference between the multiple unit ignition coils grouped together. .

FIG. 2 and subsequent figures each show some embodiments of the present invention, and components functionally the same as those used in FIG. 1 are given the same reference numerals.

The core of the first embodiment shown in FIG. 2 consists of two sets of E-shaped cores 1 and 1' as in FIG. 1, but unlike in FIG. A gap is also maintained between the opposing central legs 2 and 2' which form a common magnetic path. In accordance with the present invention, a cut groove 11 is provided in the center of each center leg 2 and 2' along the longitudinal direction from the outer surface toward the tip of the leg, dividing the center leg substantially into left and right halves. The width of this cut groove 11 is preferably wider than the gap between the opposing tips of each leg.

As a result, one of the interrupters 8a or 8b is closed,
Even though current flows through the primary coil of unit ignition coil A or B and magnetic flux φa is generated, little or no magnetic flux φa' is generated due to the presence of the cut groove 11, so this interrupter is then opened. A high voltage is induced in the secondary coil of unit ignition coil A, causing spark plugs 9a and 10a to
Although a spark discharge occurs in this case, a high voltage is not induced in the secondary coil of the other unit ignition coil B, and therefore no spark discharge occurs in the spark plugs 9b and 10b.

Therefore, spark plugs 9a and 10a or 9b and 1
0b ignites the air-fuel mixture by spark discharge during the explosion process of the cylinder in which it is installed, but at this time, the spark plugs 9b and 10b or 9a are in the exhaust process.
In cylinders equipped with and 10a, spark plug malfunctions will not occur.

The second embodiment shown in FIG.
A pair of cores 12 are used, and both cores are opposed to each other with a gap maintained between the ends of the legs 2, 3, and 4 of the E-type core and the opposite sides of the I-type core 12. and,
Although the cut groove 11 is provided only in the center leg of the E-shaped core, it may also be provided in the center of the I-shaped core 12, if necessary.

In this embodiment as well, when one of the unit ignition coils A and B causes a spark discharge to occur in the spark plug in the cylinder in the explosion process, the other does not cause spark discharge in the spark plug in the cylinder in the exhaust process. . still,
The above explanation is for a four-cylinder internal combustion engine that has one spark plug for each cylinder, but for example, in the case of a four-cylinder internal combustion engine that has two spark plugs for each cylinder, 9a and 10a are connected at the same time. The two ignition coils 9b and 10b in one of the two cylinders to be ignited can be used as the two ignition coils in the other cylinder, and the interrupters 8a and 8b can be turned on and off at the same time. A secondary coil is connected to each of the two ignition coils of the other two cylinders which are ignited at the same time at different times, and the two interrupters are connected at the same time at different times.

Fig. 4 shows an integrated ignition coil for a six-cylinder internal combustion engine in which one ignition coil is addressed to each cylinder. They are placed facing each other with a gap in between. Then, cut grooves 11 are provided in the two central legs of each iron core, so that the three unit ignition coils A, B,
Similarly, magnetic interference is eliminated between C.

Coil assemblies 5a, 5b of each unit ignition coil,
By devising a way to attach the 5c to the iron core, it can be used for six cylinders, and if the number of central legs is increased, it can be used for eight cylinders, or it can be integrated for four cylinders with two ignition coils per cylinder. Ignition coils can also be provided. Furthermore, as is clear from FIG. 3, the same effect can be obtained by arranging a set of E-shaped cores having a plurality of center legs and a set of I-shaped cores facing each other.

After assembly, the coils and iron cores are insulated with a plastic layer 13 as shown in the figure, and at that time, primary terminals 14 that connect each primary coil to the battery and interrupter, and high-voltage terminals that connect each secondary coil to the spark plug. 15
is fixed with a plastic layer 13, and the above-mentioned plastic is inserted and filled into each cut groove 11 to further enhance the effect.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a conventional centralized ignition coil, Fig. 2 is a sectional view of a first embodiment of the present invention, Fig. 3 is a sectional view of a second embodiment, and Fig. 4 is a sectional view of another embodiment.
This is a sectional view of the embodiment. In the figure, 2 and 2' are central legs forming a common magnetic path, 3 and 3', 4 and 4' are side legs forming a leg magnetic path, and 5a, 5b, and 5c are coils. assembly,
11 indicates a cut groove.

Claims (1)

[Claims for Utility Model Registration] A common magnetic path, and leg magnetic paths located on one side and the other side of the common magnetic path in the transverse direction, respectively facing the common magnetic path, A centralized ignition coil in which a coil assembly consisting of a concentric primary coil and a secondary coil is attached to the leg magnetic path, characterized in that the common magnetic path is provided with a cut groove along its longitudinal direction. Centralized ignition coil.