JPH0132644B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ignition coil that is mounted integrally with a distributor.

Conventionally, the ignition coil that is installed integrally with the distributor has a pair of E-type iron cores facing each other, and the primary and secondary coils are attached to the center leg of the coil across both cores. The structure used is that it is housed inside a case, and the inside of the case is filled with molding resin such as thermosetting epoxy resin and molded. When installing this ignition coil in a distributor, cut out a part of the housing of the distributor, insert a part of the ignition coil into the notch, and attach it to the support provided on the housing of the distributor. Secure the ignition coil with bolts.

The resin case of the ignition coil is thick in the part where the primary and secondary coils are present, and thin in the part where these coils are not present.
Next, since the secondary coil is applied evenly to both of the cores, the thinner part of the case is located evenly above and below the junction of the cores.
The width of the thinner part on the other side is smaller. Therefore, when attaching the ignition coil to the distributor, the ignition coil should be moved away from the rotation axis of the distributor in order to avoid contact between the governor section located inside the distributor and the thick part of the ignition coil case. It is necessary to place them far apart or to place the ignition coil above the distributor, that is, to the side of the cap. In the former case, the circumferential dimension of the distributor increases, and in the latter case, the height of the distributor increases, resulting in increased vibrations applied to the ignition coil.

The purpose of the present invention was to solve the above problems, and in a rectangular closed magnetic circuit formed by two iron cores, a primary coil and a secondary coil are provided only on one long side. It is coaxially wound and molded with resin to form a large volume, and the other long side of the closed magnetic circuit is only the iron core, and a relatively large disk is formed on the lower side of the distributor. The above-mentioned large-volume portion is placed in the space close to the rotating shaft, and the remaining space inside the distributor is effectively utilized to place the ignition coil at the bottom inside the distributor. An object of the present invention is to provide an ignition coil for an internal combustion engine.

Hereinafter, the present invention will be explained in detail according to embodiments shown in the drawings.

FIG. 1 is a plan view of a distributor integrally fitted with an ignition coil according to an embodiment of the present invention, with the cap removed, and FIG. 2 is a sectional view taken along the line -- in FIG. 1. The distributor 100 includes a housing 110 and a cap 12.
Contains 0. The housing 110 includes a first cylindrical part 111 and a large-diameter second part connected to the upper end of the first cylindrical part 111.
It has a cylindrical portion 112. On the other hand, cap 120
A power distribution cap part 121 that covers the second cylindrical part 112 of the housing 110 and an ignition coil cap part 122 that covers the ignition coil on the side thereof.
has.

The cap 120 is attached to the upper end of the second cylindrical portion 112 of the housing 110 with screws (not shown). At this time, a seal ring 130 is interposed at the abutting portion between the housing 110 and the cap 120, so that the abutting portion It is sealed. Note that the housing 110 is formed with two flanges 113 for fixing the power distributor to a mounting portion on the internal combustion engine side (not shown).

A first rotating shaft 140 is inserted into the first cylindrical part 111 of the housing 110, and its upper end is connected to the second cylindrical part 111.
It is located inside the cylindrical portion 112 of. A cylindrical second rotating shaft (power distribution shaft) 150 is fitted into this upper end, and the first and second rotating shafts 140, 150
are connected by a well-known governor mechanism 160. The first rotating shaft 140 has a gear 141 at its lower end, is connected to an internal combustion engine (not shown) via this gear, and is rotated in proportion to the rotational speed of the internal combustion engine.
The second rotation shaft 150 rotates by being advanced by an amount corresponding to the engine rotation speed with respect to the first rotation shaft 140 by the operation of the governor mechanism 160.

Inside the second cylindrical portion 112 of the housing 110, a plate 17 is provided above the governor mechanism 160.
0 is fixed with a screw 171. plate 1
A cylindrical support member 172 is coupled to 70 , and the second rotating shaft 150 is inserted through the inside thereof and rotatably supported by the support member 172 by a bearing bush 151 .

A signal rotor 175 is fixed to the second rotating shaft 150 above the part supported by the support member 172.
An electromagnetic pickup 176 serving as a rotation signal generator is disposed inside the motor. The signal rotor 175 has the same number of protrusions 175a as the number of cylinders of the internal combustion engine, here four protrusions 175a, and the effect of each protrusion upon rotation gives a change in magnetic flux to the electromagnetic pickup 176. The electromagnetic pick-up 176 holds a coil part 176a, which is a coil molded with resin, on a first bracket 176b, and a permanent magnet 176c between the first bracket 176b and the second bracket 1.
76d. The second bracket 176d is rotatably held on the outer periphery of the support member 172 by a bearing bush 177, and thereby the entire pickup 176 is also held. In this pick-up 176, the magnetic flux generated by the permanent magnet 176c passes through a magnetic circuit (dashed line in FIG. 2) consisting of a second bracket 176d, a bearing 177, a power distribution shaft 150, a signal rotor 175, and a first bracket 176b, and passes through a coil section. It is linked to the pickup coil in 23. The pick-up coil has a magnetic flux sensitive direction in the radial direction of the signal rotor 175, and this magnetic flux changes with the rotation of the signal rotor 175, thereby generating a rotation signal voltage in synchronization with the rotation of the rotating shaft 150 in the pick-up coil. . This rotation signal voltage is amplified by the ignition amplifier 195 to turn on and off the power transistor, thereby controlling the primary coil 1 of the ignition coil 10.
Controls energization to 1. When the power to the primary coil is cut off, a high voltage is generated in the secondary coil 12, and this high voltage is distributed to each cylinder via the center electrode 200, the rotor electrode 211 of the power distribution rotor 210, and the side electrodes 220. ignite it.

Second bracket 1 of the pick-up 176
A pin 27 is provided at 76d, and the housing 11
A rod 181 of a well-known negative pressure advance angle mechanism 180 is connected to the pin 178. Therefore, the pickup 176 is rotated relative to the support member 172 (and therefore the signal rotor 175) by the operation of the negative pressure advance mechanism 180. This rotation of the pick-up 176 and the above-mentioned first rotating shaft 1
As is well known, the ignition timing changes in each cylinder due to the rotation of the second rotating shaft 150 (signal rotor 175) with respect to the second rotating shaft 150 (signal rotor 175).

The ignition coil 10 is attached to the side of the distributor 100, particularly the housing 110. In order to attach the ignition coil 10, a portion of the second cylindrical portion 112 of the housing 110 is cut out, and two struts 114 are provided on both sides of the second cylindrical portion 112. The ignition coil 10 is fixed to the support column 114 with a mounting bolt 46, with a portion inserted into the notch.

The ignition coil 10, as shown in FIG.
It has a primary coil 11, a secondary coil 12, a pair of L-shaped iron cores 13a and 13b combined as shown in the figure, a resin case 14, and a molded resin 15.
The primary and secondary coils 11 and 12 are coaxially wound around one iron core 13a, with the secondary coil facing toward the outer periphery. These are housed inside a case 14, filled inside the case 14, and then molded with a molding resin 15 such as a hardened thermosetting epoxy resin. L type iron core 13
A and 13b are formed by laminating L-shaped thin steel plates as shown in the drawing in a direction perpendicular to the plane of the drawing, and have approximately the same width and thickness (laminated thickness). These cores are combined to form a single rectangular closed magnetic circuit as shown. The iron cores 13a and 13b have holes 16 used for fixing them to the housing with bolts.
It is provided at each corner of the combined iron core, and any two
The ignition coil is secured to the post 114 using three or more holes. When the ignition coil 10 is attached to the distributor, as can be understood from FIG. 2, the primary coil 13a and the secondary coil 1 are coaxially wound.
3b is the rotation axis 1 of the distributor
40 and 150, the directions are approximately perpendicular to 40 and 150.

A flange 441 is formed on the side surface of the case 14 of the ignition coil 10 and is aligned with the upper surface of the housing 110.
2 are in contact. Therefore, the ignition coil 10 is covered with a cap 120.

An ignition amplifier 195 is fixed to the inner wall of the second cylindrical portion 112 of the housing 110 by suitable means such as screws (not shown). This amplifier 195
The electronic element such as a power transistor is placed in a metal case 195a which also serves as a heat sink, and is surrounded by a resin case 195b. Lead wires 33 and 34 are connected to the pickup 176 and the ignition coil 10, respectively. It is connected at
Amplifier 195, lead wire 3 from ignition coil 10
5 and 47 are pulled out to the outside through a grommet 190 attached to the housing 110, and connected to an on-vehicle battery (not shown).

One end of a center electrode 200 is placed at the center of the top of the power distribution cap portion 121 of the cap 120, and a brush 202 loaded with a spring 201 is placed here. A power distribution rotor 210 is attached to the upper end of the power distribution shaft 150,
A rotor electrode 211 is fixed on the top surface of the rotor electrode 211,
The brush 202 is in contact with this rotor electrode 211. The center electrode 200 is the ignition coil cap part 1
22 and is located at the other end above the ignition coil 10 and is also provided with a brush 204 loaded with a spring 203. The ignition coil 10 is correspondingly provided with a high voltage terminal 48 connected to a secondary coil, and a cylindrical tower portion 49 is attached to the case 1 so as to surround this.
It is provided integrally with 4. And brush 20
4 is in contact with this high voltage terminal 48. Therefore, the high voltage of the ignition coil 10 is applied to the center electrode 200 and guided to the rotor electrode 211 via this.
Note that the connection between the center electrode 200 and the ignition coil 10 is completed simply by attaching the cap 120 to the housing 110.

Around the top of the power distribution cap portion 121 of the cap 120, side electrodes 220 are provided in the same number as the number of cylinders of the engine (four in this case). This side electrode 220 is led to a tower portion 123 that projects laterally of the cap 120. Side electrode 220
As the power distribution rotor 210 rotates, the rotor electrodes 211 are successively opposed to each other, and high voltage is distributed. This high voltage is guided to a spark plug (not shown) connected to the tower portion 123 via a high voltage cord.

Figure 4 shows a conventional ignition coil 1 using an E-type iron core.
0' is shown. This ignition coil 10' includes a primary coil 11', a secondary coil 12', and a pair of E-shaped iron cores 13.
a', 13b', a resin case 14, and a mold resin 15. The pair of iron cores 13a' and 13b' form an air gap between the central legs, and the primary and secondary coils 11' and 12'
A secondary coil is concentrically assembled to the central leg portions of a' and 13b' so as to face the outer periphery. Similar to FIG. 3, these are housed inside a case 14, filled inside the case 14, and then molded with a molding resin 15 such as a hardened thermosetting epoxy resin.

In the ignition coil 10' configured in this way, the magnetic flux generated by the coils 11' and 12' is divided into approximately two parts and passes through the legs on both sides. width) can be made relatively small. In other words, from the point of view of the magnetic flux density inside the core, theoretically the width A (and the width of both legs)
may be 1/2 the width of the central leg. The thickness of the case 14' in the area where the primary and secondary coils are wound (the case dimension in the direction perpendicular to the page)
The thickness of the case corresponding to the width A must be increased to prevent the ignition coil 10' from coming into contact with the governor mechanism 160 when the ignition coil 10' is installed in the distributor housing. Make it as thin as possible. However, as mentioned above, since the width A is small, there are few areas where the case 14' can be made thinner, and the ignition coil 10' is installed as close as possible to the rotating shafts 140, 150 of the distributor. It must be installed relatively above.

On the other hand, in the ignition coil 10 shown in FIG.
Since the magnetic flux generated by the coils 11 and 12 all passes through a single closed magnetic path formed by the iron cores 13a and 13b (leakage flux is not considered), the iron cores 13a and 13b have equal cross-sectional areas. Designed. Normally, the laminated thicknesses of the iron cores 13a and 13b are equal, and the widths of both iron cores are almost equal. If the capacities of the ignition coil 10 and the ignition coil 10' shown in FIG. Since the width should be equal to the width, the width of the iron core 13b, that is, the width B is equal to the width of the ignition coil 1.
This is twice the width A at 0', and therefore the portion of the case 14 whose thickness can be reduced corresponding to the width B is enlarged. As shown in FIG. 2, by arranging the ignition coil 10 with this enlarged thinner part facing the governor mechanism 160, the ignition coil 10 is placed as close as possible to the rotation axis of the distributor, and the comparison of the distributor An ignition coil 10 can be attached below the target.

As the ignition coil can be mounted relatively below the distributor, vibrations applied to the ignition coil can be reduced, and since it can be mounted as close as possible to the rotation axis of the distributor, the dimensions of the distributor can be reduced. can do.

FIG. 5 shows an ignition coil 10'' according to another embodiment of the present invention. In this embodiment, instead of the pair of L-shaped cores 13a and 13b in FIG. Two U-shaped cores 13b" are used. The I-shaped core 13a" includes a primary coil 11",
A secondary coil 12'' is wound in the same manner as in the previous embodiment. These cores and coils are housed inside a resin case 14'', and the inside of the case 14'' is filled with mold resin 15''. The provision of a mounting hole 16'' is the same as in the previous embodiment.It will be clear that this embodiment also provides the same effects as described above when attached to a distributor.

As is clear from the above description, according to the present invention, the configuration of the ignition coil is changed and the space remaining in the distributor near the rotation axis is effectively used to distribute the ignition coil. By disposing it inside the user, there is an effect that the distributor can be downsized.

[Brief explanation of drawings]

FIG. 1 is a plan view of a distributor with the cap removed, in which an ignition coil according to an embodiment of the present invention is attached, FIG. 2 is a sectional view taken along the line - in FIG. 1, and FIG. 2 is a sectional view of an ignition coil shown in FIG. 2, FIG. 4 is a sectional view of an ignition coil using a conventional E-type iron core, and FIG. 5 is a sectional view of an ignition coil according to another embodiment of the present invention. Explanation of code, 10,10″...Ignition coil, 1
1,11''...Primary coil, 12,12''...Secondary coil, 13a, 13b, 13a'', 13b''...Iron core, 100...Distributor, 110...
Housing, 140, 150...rotating shaft.

Claims (1)

[Scope of Claims] 1. An ignition coil for an internal combustion engine that is attached to the housing of a distributor, which forms a rectangular annular single closed magnetic path when combined. 2.
a primary coil and a secondary coil are coaxially wound around a portion forming one long side of the closed magnetic circuit in one of the two iron cores, and the whole is molded with resin; In the ignition coil for an internal combustion engine, the ignition coil for an internal combustion engine includes a coil not wound around a portion of the other of the two cores that forms the other long side of the closed magnetic path, and the ignition coil is disposed above a governor mechanism in the distributor. A large volume portion of the one iron core around which the primary coil and secondary coil are wound is disposed in a relatively large space formed on the side of the distribution rotor and signal rotor, and the coil is attached to the inner side of the housing of the distributor so that a portion forming the other long side of the closed magnetic path of the other iron core that is not wound is disposed at a side position of the governor mechanism; An ignition coil for an internal combustion engine characterized by: