JPH0441252Y2 - - Google Patents

Description

[Detailed description of the invention] A. Purpose of the invention (1) Industrial application field The present invention is an ignition device for an internal combustion engine, in particular, a pulse generator and an ignition coil are disposed in a housing of a power distributor, and A signal rotor having a protrusion corresponding to the number of cylinders of an engine on its outer peripheral surface, an iron core whose tip end can face each protrusion of the signal rotor, and a generator wound around the iron core with one end facing the ignition coil. The present invention relates to an improvement in a pickup coil which is equipped with a pickup coil and has a tip of the core protruding from the one end surface, and a magnet coupled to the core.

(2) Prior art The pulse generator and ignition coil are
Because it is built into the narrow housing of the power distributor, leakage flux from the ignition coil acts on the pickup coil.

Conventionally, a magnetic shielding plate was placed between the ignition coil and the pulse generator (U.S. Patent No.
4129107).

On the other hand, in order to prevent a pick-up coil from being removed from the iron core, an adhesive is applied to the synthetic resin bobbin of the pick-up coil and polymerized to the stopper provided on the iron core, and a plurality of retaining protrusions protruding from the bobbin are applied to the stopper. The protrusions are inserted through a plurality of insertion holes, respectively, and the protruding portions of the retaining protrusions are heated and formed into the shape of a rivet head.

(3) Problems to be Solved by the Invention However, when the magnetic shielding plate is provided as described above, there is a problem in that the housing and, by extension, the device become larger depending on the space occupied by the magnetic shielding plate.

On the other hand, when preventing the pick-up coil from coming off as described above, adhesive and heating means are required to prevent the pick-up coil from coming off, which not only causes high costs, but also
There is a problem in that it requires a lot of work because it involves applying adhesive and molding the protruding portions of each retaining projection.

SUMMARY OF THE INVENTION An object of the present invention is to provide an ignition device that can solve the above problems.

B. Structure of the invention (1) Means for solving the problems In order to achieve the above object, the invention disposes a pulse generator and an ignition coil in the housing of a power distributor, and the pulse generator , a signal rotor having protrusions on its outer circumferential surface corresponding to the number of cylinders of the engine; an iron core whose tip end can face each protrusion of the signal rotor; and a signal rotor wound around the iron core with one end facing the ignition coil. In the ignition device for an internal combustion engine, the pick-up coil has the tip of the iron core protruding from the one end surface, and a magnet coupled to the iron core. The tip of the iron core is overlapped with the one end surface of the pick-up coil, and the tip of the iron core is passed through the insertion hole formed at the tip of the magnetic shielding plate, and a stopper formed integrally with the iron core is placed on the other end surface of the pick-up coil. The pick-up coil is sandwiched between the stopper and the magnetic shielding plate, and the base of the magnetic shielding plate is connected to the stopper.

(2) Effects With the structure described above, the space occupied by the magnetic shielding plate within the housing is extremely small, and therefore the housing and, by extension, the device do not need to be enlarged.

Furthermore, since the magnetic shielding plate has a function of preventing the pickup coil from coming off, one member can have two functions, thereby simplifying the structure.

Furthermore, the work of preventing the pick-up coil from coming off is extremely easily accomplished by clamping the pick-up coil between the magnetic shield plate and the stopper and by bonding the magnetic shield plate to the iron core.

Since the leakage magnetic flux of the ignition coil is shielded by the magnetic shielding plate, it is possible to suppress the noise caused by the leakage magnetic flux from being mixed into the pulse voltage generated in the pickup coil.

(3) Embodiment In FIGS. 1 and 2, the housing 1 of the power distributor D includes a cylindrical aluminum alloy housing main body 2 having an opening at one end, and a sealing member 3 in the opening. It consists of a synthetic resin cap 5 which can be fastened together with screws 4.

A centrifugal advance mechanism G, a pulse generator P, a closed magnetic circuit ignition coil, an igniter g, and a power distribution mechanism Dm to the spark plug are disposed within the housing 1, and a vacuum advance mechanism V is provided on the outer surface of the peripheral wall of the housing 1. will be placed.

First, Figures 3 to 10, Figure 12, and Figure 19.
The ignition coil will be explained using the electric circuit shown in the figure.The ignition coil is screwed to the housing body 2 via its iron core ₆₁ . Further, each part of the Tetsushin ₆₁ , such as the winding core 8, is formed to have a rectangular cross section.

In the illustrated example, the iron core 6 ₁ includes a winding core 8 , an E forming layer body c ₁ having both attachment parts 10 ₁ , 10 ₂ and a winding core holding part 11 , and a forming layer body c ₂ constituting the connecting part 12 .
It is a combination of

The coil case 13 is molded from synthetic resin into a cylindrical shape having an opening at one end and a bottom wall 15 at the other end, and during molding, the coil case 13 and the E-forming layer body _c1 are integrated. .

The arrangement relationship of each part of the E-forming layer body _c1 with respect to the coil case 13 is as follows.

That is, both mounting parts 10 ₁ and 10 ₂ are connected to the coil case 1
The core holding part 11 is attached to the outer surface of the peripheral wall 14 of the coil case 13, and the core holding part 11 is attached to the bottom wall 1 when the core 8 is passed through the bottom wall 15 of the coil case 13 and held there.
5 Can be attached to the outside surface. The forming layer body c ₂ and therefore the connecting portion 12 is formed by forming the primary and secondary layers on the core 8, which will be described later.
After the next coil is wound, the ends of the two attachment parts 10 ₁ and 10 ₂ are connected by means such as press-fitting the convex part 16 into the concave part 17 . The connecting portion 12 is housed within the coil case 13, and the connecting portion 12 and both mounting portions 10
A pair of _U -shaped protrusions 18 surrounding the tips of both mounting portions 10 ₁ and 10 ₂ are formed on the opposing portion of the peripheral wall 14 of the coil case 13 so that the connecting portions with the mounting portions 10 1 and 10 ₂ are located within the coil case 13. be done.

In the core holding portion 11, the three exposed surfaces excluding the surface facing the outer surface of the bottom wall 15 of the coil case 13 are as follows:
It is covered with a synthetic resin discharge prevention cover 19 ₁ that is integrally molded with _the bottom wall 15 , and as shown in FIGS. Hour winding center holding part 11
They are connected via molded synthetic resin pins 21 which are filled in the through holes 20 of the two. This pin 21 allows the cover 19 ₁ to be removed from the core holding portion 11.
Peeling is prevented. Furthermore, since the connection structure using the pins 21 can be obtained at the same time as the coil case 13 is molded, no special work is required for the connection structure after the coil case is molded, thus minimizing the increase in the number of manufacturing steps for the ignition coil. can do.

Both mounting parts 10 ₁ and 10 ₂ are screwed in contact with the pillars of the aluminum alloy housing body 2 having good thermal conductivity, as will be described later, and the coils at these mounting parts 10 ₁ and 10 ₂ Exposed surfaces other than the contact surface 22 ₁ adjacent to the surface facing the case 13 , the contact surface 22 ₂ on the opposite side to the surface facing the case 13 , and the surface facing the outer surface of the peripheral wall 14 of the coil case 13 are integrally molded with the peripheral wall 14 . It is covered with a synthetic resin discharge prevention cover ₁₉₂ .

As shown in Figs. 4 and 12, the coil case 1
A reinforcing plate 23 made of a material with low temperature dependence, for example, a steel plate is buried in approximately half of the peripheral wall 14 at 3, and both ends of the reinforcing plate 23 are connected to both mounting portions 10 ₁ ,
Both mounting portions 10 ₁ , ₁₀ are connected to each other via a discharge prevention cover 19 ₂ on the opposite side of the contact surface 22 ₁ where each screw insertion hole 9 opens.
Polymerized into ₂ .

As shown in FIGS. 4, 7 to 9, approximately half of the bottom wall 15 of the coil case 13 is constituted by an insulating wiring board 24 made of synthetic resin, and the wiring board 24 has the following structure. Various members, which are the circuit elements of FIG. 19, are provided.

That is, the first contact ₂₅₁ and the igniter g connected to the (+) side of the battery E as a power source.
A first plug 26 ₁ protruding from the outer surface of the wiring board 24 , a first plug 26 ₁ connected to the second contact 25 2 , and a first contact 25 ₁ and the primary and secondary coils 3
The first conductor 27 ₁ connects between the input terminals 33 a and 35 a of the coils 3 and 35, and the second conductor 27 1 connects between the second contact 25 ₂ and the output terminal 33 b of the primary coil 33.
Conductor 27 ₂ and first and second conductors 27 ₁ and 27 ₂
third and fourth contacts 25 respectively connected to
₃ , ₂₅₄ , and a second plug ₂₆₂ , etc., which is provided protruding from the outer surface of the wiring board 24.

The first conductor 27 ₁ is buried in the wiring board 24 , and one end of the first conductor 27 1 is located on one end side of the wiring board 24 and is exposed to the outer surface of the wiring board 24 .
₁ is formed, and the other end is exposed on the outer surface of the wiring board 24 and connected to the first contact 25 ₁ .
Similarly to the first conductor 27 ₁ , the second conductor 27 ₂ also connects to the wiring board 27 .
One end is located at the other end of the wiring board 24 and is exposed to the outer surface thereof, and a connection hole ₂₈₂ passing through the wiring board 24 is formed, and the other end is exposed to the outer surface of the wiring board 24. At the same time, the second contact 25
Connected to ₂ .

A third conductor 27 ₃ embedded in the wiring board 24 extends from the other end of the first conductor 27 ₁ .
The tip of the conductor 27 ₃ is exposed on the outer surface of the wiring board 24 and is connected to the third contact 25 ₃ . Further, a fourth conductor 27 ₄ is embedded in the wiring board 24 , one end of which is exposed on the outer surface of the wiring board 24 and connected to an intermediate exposed portion of the second conductor 27 ₂ via a resistor 29 . The other end of the fourth conductor 27 ₄ is exposed on the outer surface of the wiring board 24 and is connected to the fourth contact 25 ₄ .

The third contact 25 ₃ of the second plug 26 ₂ is connected to the igniter g, and the fourth contact 25 ₄ is connected to the tachometer T, respectively.

As shown in FIG. 9, connection holes for the first and second conductors 27 ₁ and 27 ₂ are formed in the overhanging portion 30 of the bottom wall 15 that overlaps the inner surface of the wiring board 24 at the joint portion of the wiring board 24 in the coil case 13. Guide holes 31 ₁ and 31 ₂ communicating with 28 ₁ and 28 ₂ are formed. The guide holes 31 ₁ and 31 ₂ are formed as tapered holes with large diameter ends located inside the coil case 13.

The entire inner peripheral surface of the coil case 13 and the wiring board 2
A cushion material 32 made of rubber, synthetic resin, etc. is attached to the inner surface of the bottom wall 15 except for parts 4.

A synthetic resin bobbin 34 having a primary coil 33 is fitted onto the winding core 8 of the iron core 6 ₁ , and a synthetic resin bobbin 3 having a secondary coil 35 on the outside of the bobbin 34.
6 is fitted. As a result, the primary and secondary coils 33 and 35 are wound around the winding core 8 in a double manner.

As shown in FIGS. 9 and 10, in the secondary coil bobbin 36, the bottom wall 15 of the coil case 13
A pair of connecting plates 38 ₁ and 38 ₂ are attached to the outer surface of the flange portion 37 located on the side. Those connecting plates 38
₁ and 38 ₂ may be attached, but in the illustrated example, each pair of pin-shaped protrusions 39 protruding from the outer surface of the flange portion 37 are passed through the through holes of the connecting plates 38 ₁ and 38 ₂ , and these protrusions are attached. The tip of No. 39 is thermally deformed into a rivet head shape. Both connection plates 38 ₁ , 3
8 ₂ facing each other are each bent at a substantially right angle to the outer surface of the flange portion 37 and erected on the flange portion 37, and one bent portion connects the pin-shaped first terminal 40 ₁ and the other The bent portions respectively constitute pin-shaped second terminals 40 ₂ . First terminal 40 ₁
At the other end of the connecting plate 38 ₁ having the same shape, the input terminals 33 a and 35 _a of the primary and secondary coils 33 and 35 are crimped between the bent tongue piece 38 a provided thereon and the connecting plate 38 1 . As a result, these terminals 33a, 35a and the connection plate ₃₈₁ are connected.
Furthermore, at the other end of the connecting plate 38 ₂ having the second terminal 40 ₂ , the output end 33 b of the primary coil 33 is crimped between the bent tongue piece 38 b provided thereon and the connecting plate 38 ₂ . , the terminal 33b and the connection plate 38 ₂ are connected.

The connecting portion 12 in the iron core 6 ₁ is connected to both mounting portions 10 ₁ ,
10 ₂ , the bobbin 34 having the primary coil 33 is fitted onto the core 8 with a bobbin 36 having the secondary coil 35 fitted around its outer periphery. At that time, as shown in FIGS. 7 to 9, the first and second terminals 40 ₁ , 40 ₂ are connected to the guide holes 31 ₁ , 31 _{2 .}
are guided by the first and second conductors 27 ₁ , 27 ₂
are inserted smoothly into the connection holes 28 ₁ , 28 ₂ respectively, and both terminals 40 ₁ , 40 ₂ and both conductors 27 ₁ , 27 ₂
and are connected by plug-in respectively. This facilitates the connection between the input and output terminals 33a and 33b of the primary coil 33, the input terminal 35a of the secondary coil 35, and the first plug ₂₆₁ , and also simplifies the connection structure.

First and second terminals 40 ₁ , 40 ₂ and both connection holes 2
The gap between 8 ₁ and 28 ₂ is sealed with solder 41 or the like to prevent the liquid synthetic resin from leaking during the potting process.

As clearly shown in FIGS. 1 and 4, the secondary coil bobbin 3 is located on the opening side of the coil case 13.
On the outer surface of the flange portion 42 of No. 6, a synthetic resin connecting tube 43 having an opening at one end is attached to the peripheral portion above the wiring board 24 via a concave-convex fitting portion 44 consisting of a small protrusion and a small hole. A high voltage terminal 45 is held on the bottom wall of the connection tube 43 with its upper and lower parts exposed on the inner and outer surfaces of the bottom wall, and the output side terminal of the secondary coil 35 is connected to a conductive plate 46 attached to the lower part of the high voltage terminal 45. 35b is connected.

The coil case 13 is potted using a synthetic resin R such as epoxy resin, and the connecting portion 12 of the iron core ₆₁ , the primary coil 33, the secondary coil 35, the connecting tube 43, etc. are connected through the synthetic resin R. is integrated with the coil case 13.

Next, the mounting structure of the ignition coil to the housing body 2 will be explained with reference to FIGS. 1, 2, and 11 to 13.

The housing main body 2 has a projecting portion 47 on a part of its peripheral wall, and an outlet 48 connected to a battery E, an igniter g, etc. is installed on the inner surface of the bottom wall of the projecting portion 47. The ignition coil is erected by inserting and connecting the first and second plugs 26 ₁ and 26 ₂ into the outlet 48 and placing the core holder 11 of the iron core 6 ₁ on the upper surface of the boundary wall 49 of the overhang 47 . When such a plug-in connection structure is adopted, the connection between the ignition coil and the battery E etc. is simplified.

The housing body 2 has a pair of pillars 50 ₁ erected at its opening so as to sandwich the coil case 3 therebetween.
50 ₂ , and these supports 50 ₁ , 50 ₂ are the second,
As clearly shown in FIG. 12, the cross section has a hook shape, and both mounting portions 10 of the iron core 6 ₁ are provided on the hook-shaped inner surface.
Both contact surfaces 22 ₁ and 22 ₂ of ₁ and 10 ₂ are in close contact with each other. As shown in FIG. 11, both mounting portions 10 ₁ , 1
Insert the mounting screw ₅₁ into the lower screw insertion hole 9 at 0 ₂ .
are inserted into the female screw holes 50a of the columns 50 ₁ and 50 ₂
is screwed onto.

Further, a bearing holder 52 for a drive shaft that drives a pulse generator P, which will be described later, is attached to the opening of the housing body 2 with three screws 53.
As clearly shown in FIG. 3, a pair of stays 54 ₁ and 54 ₂ are fastened to the two screws 53 together. Both stays 54
The ends of the stays 54 ₁ , 54 2 abut against the surface opposite to _{the contact surface 22 1 of} both the mounting portions 10 ₁ , 10 2 via the discharge prevention cover 19 ₂ , and are formed at the ends _of the stays 54 ₁ , 54 ₂ . screw insertion hole 54a and both mounting parts 10
Attachment screws 51 ₂ passing through the screw insertion holes 9 at the upper portions of the columns ₁ and 10 ₂ are screwed into the female screw holes 50b of the support columns 50 ₁ and 50 ₂ , respectively.

In this way, both ends of the reinforcing plate 23 buried in the coil case 13 and both attachment parts 10 ₁ of the iron core 6 ₁ ,
10 ₂ is sandwiched between the pillars 50 ₁ , 50 ₂ and the stays 54 ₁ , 54 ₂ , so that the ignition coil is firmly attached to the housing body 2 via the iron core 6 ₁ and the reinforcing plate 23 . In addition, the primary and secondary coils 33,
35 vibration can be supported by the housing body 2 via the reinforcing plate 23, thereby preventing damage to the coil case 13 and generation of cracks between the coil case 13 and the discharge prevention cover ₁₉₂ . .

Next, the power distributor D will be explained with reference to FIGS. 1, 2, and 11 to 14.

A drive shaft 55 that drives the pulse generator P is connected to the housing body 2 in parallel to the winding core 8 of the ignition coil.
One end of the drive shaft 55 is rotatably supported by the end wall 2a of the housing body 2 via a bearing 56, and the other end facing into the housing 1 is supported by a bearing 57 and a bearing 57 for holding it. It is rotatably supported by the housing body 2 via a bearing holder 52.

As clearly shown in FIG. 13, the bearing holder 52 is made of a ferromagnetic material such as iron, and includes a C-shaped support portion 58 and three leg portions 59 erected from the support portion 58. and a bearing attachment part 60 provided at the tips of the legs 59, and a screw for fixing the bearing 57 fitted in the recess 61 of the bearing attachment part 60 to the retaining plate 62 and the bearing attachment part 60. 63 to be held in the bearing holder 52. As clearly shown in FIG. 12, the support part 58 of the bearing holder 52 is fixed to the opening of the housing body 2 with three screws, and the bearing mounting part 60 and one leg part 59 are arranged near the ignition coil. be done.

An Oldham coupling 64 is attached to the protruding end of the drive shaft 55 protruding from the housing body 2, and the Oldham coupling 64 meshes with an Oldham coupling attached to a rotating shaft such as a camshaft driven by an engine (not shown). As a result, the drive shaft 55 is driven by the engine.

A hollow rotor shaft 65 is rotatably fitted to the drive shaft 55 between the bearings 56 and 57. Bearing 5
One end of the rotor shaft 65 located on the 6 side and the drive shaft 55
and is connected via a centrifugal advance mechanism G.

The centrifugal advance mechanism G includes a base plate 66 integrally fixed to the drive shaft 55, an ignition timing plate 67 integrally fixed to the rotor shaft 65, and a pair of weights swingably supported by the base plate 66. 68, and a pair of springs 71 stretched between the support pin 69 of the weight 68 and the support pin 70 erected on the ignition timing plate 67.

As shown in Figures 1, 2, 14 to 17,
A pulse generator P described below is arranged around the rotor shaft 65.

That is, a signal rotor 72 having protrusions 72a corresponding to the number of cylinders of the engine is fixed to the outer peripheral surface of the rotor shaft 65. An annular rotating plate 76 is disposed between the signal rotor 72 and the centrifugal advance mechanism G, and the rotating plate 76 is mounted on a bearing on the inner peripheral surface of an annular body 74 fixed to a step 73 of the housing body 2. It is rotatably supported via 75. The ring body 74 is fixed to the step portion 73 via a presser plate 84 and a screw 85 ₁ that fixes it to the housing body 2 .

As clearly shown in FIG. 14, an L-shaped support fitting 78 made of a magnetic material is disposed on the rotating plate 76.
The support fitting 78 includes a mounting plate 78a fixed to the rotating plate 76 by a pair of screws 77, and a support plate 78b rising from the side edge of the mounting plate 78a on the housing body 2 side.

A base end portion of the magnetic shielding plate 82 is superimposed on the surface of the support plate 78b facing the signal rotor 72,
Further, the base end portions of the magnet 79 and the plate iron core 80 are superimposed in this order on the surface of the support plate 78b facing the housing body 2, and these four members 78
b, 79, 80, and 82 pass through the magnetic shielding plate 82, the support plate 78b, and the magnet 79 to connect the iron core 80.
are connected together by a pair of screws 85 ₂ screwed into the proximal end of the . The magnetic shielding plate 82 is made of non-magnetic and conductive aluminum or copper.

The iron core 80 consists of a mounting plate 80a that is bent along the inner surface of the housing body 2 and includes the base end portion, and a coil winding plate 80b that is connected to the mounting plate 80a so as to be substantially perpendicular to the mounting plate 80a. The tip end e of the coil winding plate 80b is connected to the signal rotor 72.
It is adapted to be able to face each protrusion 72a of.

The insertion hole 90a (FIGS. 15 to 17) of the bobbin 90 in the pick-up coil 81 is fitted into the coil winding plate 80b of the iron core 80, thereby winding the pick-up coil 81 onto the coil winding plate 80b. One end surface of the pick-up coil 81 faces the ignition coil, and the tip portion e of the coil winding plate 80b projects from the one end surface. Further, the other end surface of the pick-up coil 81 comes into contact with a mounting plate 80a which functions as a stopper.

An insertion hole 82a is provided at the tip of the magnetic shielding plate 82.
is formed, and the coil winding plate 8 is inserted into the insertion hole 82a.
The tip e of 0b passes through the pick-up coil 8.
1 is sandwiched between the mounting plate 80a and the magnetic shielding plate 82. In this sandwiched state, the base end of the magnetic shielding plate 82 is fixed to the support plate 78b with the screw ₈₅₂ as described above, so that the pick-up coil 81 is prevented from coming out and the iron core 80, the magnet 79, and the magnetic shielding plate 82 are secured. Bonding is done in the same step.

A magnetic transmission plate 83 is fixed to the rotor shaft 65 inside the rotating plate 76 .

As clearly shown in FIGS. 1 and 2, a part of the flat surface of the rotating plate 76 in the pulse generator P digs into the projected plane of the coil case bottom wall 15 in the ignition coil, and the biting part 76a A connecting pin 86 is erected so as to protrude toward the bottom wall 15. A connecting rod 87 of the vacuum advance mechanism V is connected to the connecting pin 86 via an elongated hole 88 formed at its tip. The elongated hole 88 is formed to be long in the radial direction of the rotating plate 76, so that when the connecting rod 87 is indexed, the connecting rod 87 and the connecting pin 86
It is designed so that there will be no tension between them.

When a part of the flat surface of the rotary plate 76 bites into the projection plane of the coil case bottom wall 15 of the ignition coil as described above, the amount of protrusion of the housing 1 for accommodating the ignition coil will depend on the amount of the bite. This can reduce the size of the housing 1, thereby suppressing the increase in size of the housing 1.

14 to 17 show the connection between the pick-up coil 81 and a pair of lead wires 89, 94, and a pair of support arms are provided on the side of the flange portion 91 on the opposite side of the magnetic shielding plate 82 in the bobbin 90 of the pick-up coil 81. 92 ₁ and 92 ₂ are provided protrudingly. Winding start terminal 93a and winding end terminal 93 of coil 93
b is connected to the terminals 89a and 94a of the input and output side lead wires 89 and 94 via solder 95, respectively, and is connected between the vicinity of the winding start terminal 93a and the input side lead wire terminal 89a and the winding end terminal 9.
3b and the output side lead wire terminal 94a are connected by connectors 96 ₁ and 96 ₂ , respectively.

Terminals 89a and 9 of both lead wires 89 and 94
4a is aligned with the positioning groove 97 of both support arms 92 ₁ and 92 ₂ in the bobbin 90,
Both support arms 92 ₁ , 92 ₂ and the above-mentioned neighboring portions are bound together by a flexible heat-shrinkable tube 98 attached thereto. In this case, the tubes 98 may be adhered to the support arms 92 ₁ , 92 ₂ and the lead wires 89 , 94 using an adhesive coated on the inner peripheral surface of the heat shrink tubes 98 .
It is also possible to employ tape wrapping as this type of binding means.

In this way, both support arms 92 ₁ of the bobbin 90,
When 92 ₂ and both lead wires 89 and 94 are tied together, if both lead wires 89 and 94 vibrate or tensile force is applied to these lead wires 89 and 94, those vibrations and tensile forces will be transmitted to both support arms. supported by the bobbin 90 via 92 ₁ and 92 ₂ ;
As a result, the vibration and tensile force are applied to the winding start terminal 93a of the coil 93 and the terminal 8 of the input side lead wire 89.
9a and the connection between the winding end terminal 93b and the terminal 94a of the output side lead wire 94, thereby preventing disconnection of both connections and disconnection of both connectors 96 ₁ and 96 ₂ . be done.

Input side lead wire 89 and output side lead wire 94
is connected to igniter g.

The igniter g is attached to the inner surface of the peripheral wall of the housing body 2 by a pair of screws 114 between the pickup coil 81 and the ignition coil.

Next, the power distribution mechanism Dm to the spark plug 113 will be explained with reference to FIG.

The power distribution rotor 99 includes a synthetic resin body 101 that is fitted onto the drive shaft 55 and fixed with a screw 100;
It consists of a power distribution electrode 102 embedded and held in the synthetic resin body 101. The distal end of the power distribution electrode 102 protruding from the synthetic resin body 101 is configured such that one end protrudes into the cap 5 and can face a side electrode 103 embedded and held in the cap 5. A plurality of side electrodes 103 are provided according to the number of cylinders of the engine, and these are connected to a plurality of spark plugs 113, respectively. The base end of the power distribution electrode 102 is exposed at the center of the end surface of the synthetic resin body 101, and the carbon center electrode 10 provided on the cap 5 is attached to the base end.
4 is designed to make sliding contact.

The center electrode 104 is held in a conductive cylinder 105 embedded in the cap 5 via a conductive spring 106, and one end of a conductive rod 107 buried in the cap 5 is connected to the conductive cylinder 105. Conductive rod 1
A conductive tube 108 formed at the other end of the cap 5 is embedded in a cylindrical portion 109 protruding from the inner surface of the top wall of the cap 5 and opens into the cap 5, and a conductive spring 110 is inserted into the conductive tube 109. A conductive electron 111 having the same configuration as the center electrode 104 is held. As a result, when the cap 5 is placed over the opening of the housing body 2, the cylindrical portion 109 is fitted into the connecting tube 43 of the ignition coil, and the center electrode 104 and the conductor 111 are fitted.
are connected to the distribution electrode 102 and the high voltage terminal 45, respectively, and their connection state is determined by the spring 10.
The center electrode 104 is urged toward the power distribution electrode 102 and the conductor 111 is urged toward the high-voltage terminal 45 with the elastic force of 6,110, respectively, so that the center electrode 104 is reliably maintained.

Next, the operation of the above embodiment will be explained.

When the engine is operated and the drive shaft 55 is rotated, the rotor shaft 65 and therefore the signal rotor 72 are rotated via the centrifugal advance mechanism G. When each protrusion 72a of the signal rotor 72 faces the tip e of the iron core 80 in the pulse generator P, the magnet 79, the iron core 80, the signal rotor 72, the rotor shaft 65, the magnetic transmission plate 83, the rotation plate 76, and the support metal fittings are connected. A magnetic flux is formed between the magnet 78 and the magnet 79, and then the magnetic flux changes as the protrusion 72a and the tip e are offset, so that a pulse-like voltage is generated in the pickup coil 81. That voltage is the primary coil of the ignition coil 3 of the igniter g.
3 is operated to cut off the primary current flowing through the coil 35, a high voltage is generated in the secondary coil 35, and the high voltage is applied to the high voltage terminal 45, the conductive element 111, and the conductive rod 10.
7. It is distributed to the corresponding side electrodes 103 via the center electrode 104 and the power distribution electrode 102, and causes the spark plug 113 to spark.

At this ignition timing, the rotation of the drive shaft 55 is transmitted to the rotor shaft 65 via the centrifugal advance mechanism G, and the rotation speed of the signal rotor 72 is accelerated, so that the protrusion 72a of the signal rotor 72 and the tip e of the iron core 80 are opposed to each other. The angle is advanced by shortening the time from one to the next confrontation. Further, since the rotary plate 76 is rotated by the vacuum advance mechanism V, the ignition timing is also advanced by this.

In this case, a certain amount of the leakage magnetic flux of the ignition coil on the pickup coil 81 side is bypassed to the bearing holder 52 made of a ferromagnetic material and disposed close to the ignition coil. Further, a certain amount of the leakage magnetic flux reaches the conductive magnetic shielding plate 82 in the pickup coil 81 and generates an eddy current there, and the leakage magnetic flux is canceled by the eddy current.

Such a bearing holder 52 and magnetic shielding plate 8
2, the pick-up coil 81
It is possible to suppress the noise caused by the leakage magnetic flux of the ignition coil from being mixed into the pulsed voltage generated in the ignition coil.

In addition, the heat generated by the iron core 6 ₁ in the ignition coil is
Both contact surfaces 22 ₁ , 22 ₂ of both mounting portions 10 ₁ , 10 ₂ come into close contact with the hook-shaped inner surfaces of both struts 50 ₁ , 50 ₂ , so that conduction is conducted to the housing body 2 through these struts 50 ₁ , 50 ₂ . Since the housing main body 2 and both struts 50 ₁ and 50 ₂ are made of aluminum alloy, they have good thermal conductivity, and thus the iron core 6 ₁ can be efficiently cooled.

Further, both mounting portions 10 ₁ and 10 ₂ in the iron core 6 ₁
The exposed surfaces of the core holder 11, excluding both contact surfaces 22 ₁ and 22 ₂ , are covered with discharge prevention covers 19 ₁ and 19 ₂ , respectively, and the connecting portion 12 is located inside the coil case 13. Because of this arrangement, discharge of the iron core 6 ₁ can be suppressed as much as possible.

Furthermore, since the reinforcing plate 23 of the coil case 13 has low temperature dependence, the amount of expansion associated with the heat generated by the iron core ₆₁ is small, resulting in problems such as destruction of the coil case 13 due to expansion of the reinforcing plate 23. Never.

Furthermore, due to the heat generated by the iron core ₆₁ and its cooling, the synthetic resin R used in the potting process expands and contracts, but the amount of expansion is
Since it is absorbed by the compression of 2, the coil case 13
damage is prevented. In addition, since the shrinkage of the synthetic resin R is followed by the restoration of the cushion material 32, the generation of a gap between the synthetic resin R and the coil case 13 is prevented, thereby preventing the occurrence of creeping discharge due to the gap. Problems can be avoided.

FIG. 18 shows various iron cores 6 ₁ to 6 ₃ used in closed magnetic circuit type ignition coils, and these iron cores 6 ₁ to 6 ₃ are composed of laminated bodies of anisotropic silicon steel plates.

FIG. 18a shows the iron core 6 ₁ of the ignition coil, and the iron core 6 ₁ is arranged on both sides of the winding core 8 so as to cooperate with the winding core 8 to form a closed magnetic path. A pair of magnetic path forming bodies 112 are provided. In the illustrated example, the magnetic path forming frame 7 is configured by a pair of magnetic path forming bodies 112 . Both magnetic path forming bodies 112 are arranged on a pair of first permeable magnetic paths p1 formed in a pair of attachment parts 10 ₁ and 10 ₂ parallel to the axis of the winding core 8, and on both ends of both attachment parts 10 ₁ and 10 _2. It has a pair of second and third magnetic permeable paths p2 and p3 formed in each half of the core holding part 11 and the connecting part 12, which are arranged perpendicular to the axis of the core 8.

The direction of easy magnetization of the anisotropic silicon steel plate is parallel to the axis of the winding core 8 and both the first and third magnetic permeable paths p1 and p3, as shown by arrow M, and is parallel to the axis of both the first and third magnetic permeable paths p1 and p2, as shown by arrow M. perpendicular to their axes.

With the above structure, each constituent plate of the E-forming layer body _c1 can be punched out of the anisotropic silicon steel plate at the same time, improving the material yield, and reducing the number of man-hours for punching each constituent plate and their configuration. The number of assembly steps for assembling the E-forming layer body c ₁ and the forming layer body c ₂ made of plates into a frame shape is calculated based on the winding core 8 and each magnetic permeable path p1.
The easy magnetization direction of ~p3 can be reduced to one-third of that when parallel to their axes.

The reason for this is that when the direction of easy magnetization of the winding core 8, etc. is made parallel to their axis, each constituent plate of the E-forming layer _c1 is composed of five punched plates as shown by the chain lines in Fig. 18a. Because you have to.

In the iron core 6 ₁ , the direction of easy magnetization in the second magnetic permeable path p2 is perpendicular to the axis as shown by the arrow M, so the magnetic properties are somewhat degraded in the second magnetic permeable path p2, but the winding core 8 If the direction of easy magnetization is parallel to the center line of the primary and secondary coils 33, 35, the magnetic properties of the entire iron core ₆₁ are:
This is comparable to the case where all the easy magnetization directions of the winding core 8 and each of the permeable paths p1 to p3 are made parallel to their axes.

The iron core 6 ₂ in FIG. 18b has a pair of E-forming layer bodies c ₁ ,
c ₁ are butted against each other, and similarly to a above, it is provided with a pair of magnetic path forming bodies 112. However, the direction of easy magnetization of the anisotropic silicon steel plate is parallel to the axis of the winding core 8 and both first magnetic permeable paths p1, as shown by arrow M, and parallel to the axes of both second and third magnetic permeable paths p2, p3
is perpendicular to those axes. In this case, the man-hours for the punching work and the man-hours for the assembly work can be reduced to one-fourth of what would be required if the directions of easy magnetization of the winding core 8 and the like were made parallel to their axes.

The iron core 6 ₃ in FIG. 18c includes a pair of U-forming layer bodies c ₃
are combined into a rectangular frame shape, and the portions of both U-forming layer bodies _c3 that face each other with a gap in between function as the winding core 8. The magnetic path forming body 112 is connected to the winding core 8
a first magnetic permeable path p1 parallel to the first magnetic permeable path p1 and a first magnetic permeable path p1 parallel to
A second
and third magnetic permeable paths p2 and p3.

The direction of easy magnetization of the anisotropic silicon steel sheet is parallel to the axes of the winding core 8 and the first magnetic permeable path p1, as shown by arrow M, and is parallel to the axes of the core 8 and the first magnetic permeable path p1.
2 and p3, it is perpendicular to those axes. In this case, compared to the case where the direction of easy magnetization of the winding core 8 etc. is made parallel to their axes, the number of man-hours for the punching work is reduced to two-fifths, and the number of man-hours for the assembly work is reduced to one-fourth.
can be reduced respectively.

C. Effect of the invention As described above, according to the invention, the tip of the non-magnetic and conductive magnetic shielding plate can be picked up by the coil.
The tip of the iron core is overlapped with one end face facing the ignition coil, and the tip of the iron core is passed through the insertion hole formed at the tip of the magnetic shielding plate, and a stopper formed integrally with the iron core is brought into contact with the other end face of the pick-up coil. Then, the pick-up coil was sandwiched between the stopper and the magnetic shielding plate, and the base of the magnetic shielding plate was bonded to the stopper, so that the magnetic shielding plate could be superimposed on one end surface of the pickup coil. Therefore, the space occupied by the magnetic shielding plate within the housing is extremely reduced, and therefore, even with the special installation of the magnetic shielding plate, the housing and, by extension, the device do not become larger.

Moreover, the above-mentioned magnetic shielding plate can be installed by simply placing a pick-up coil between the tip of the magnetic shielding plate and a stopper formed integrally with the iron core, and simply bonding the base of the magnetic shielding plate to the stopper. Since the coil can be securely fixed to the iron core by mechanically clamping the coil, the work process for preventing the pick-up coil from coming off from the iron core is simplified compared to the conventional method, and the work efficiency is improved. Moreover, since the magnetic shielding plate for shielding the leakage magnetic flux of the ignition coil can also be used as a retaining means for preventing the pickup coil from falling off from the iron core, the coil retaining structure is simpler. This, together with the aforementioned effect of improving work efficiency, can greatly contribute to cost reduction.

[Brief explanation of the drawing]

Figures 1 and 2 show the ignition coil/distributor assembly, Figure 1 is a sectional view taken along the line shown in Figure 2, Figure 2 is a sectional view taken along the line taken in Figure 1, and Figures 3 to 10 are ignition coils. , FIG. 3 is a perspective view of the ignition coil seen from diagonally above, FIG. 4 is a sectional view taken along the line shown in FIG. 3,
Fig. 5 is a sectional view taken along the line shown in Fig. 3, Fig. 6 is a perspective view of the iron core, Fig. 7 is a perspective view of the ignition coil in an inverted state, Fig. 8 is a bottom view of the ignition coil, and Fig. 9 is a perspective view of the iron core.
Figure-10 is a perspective view of main parts of the primary and secondary coil bobbins in an inverted state, Figures 11 to 13 show the mounting structure of the ignition coil to the power distributor, and Figure 11 is the front view. Figure 12 is the first
Figure 1 is a line sectional view, Figure 13 is an exploded perspective view showing the mounting relationship between the bearing holder and the stay, and Figure 14 is a cross-sectional view.
17 to 17 show the pickup coil of the pulse generator and its surrounding parts, FIG. 14 is a perspective view of the whole, FIG. 15 is a perspective view of the lead wire connection part, and FIG. 16 is a perspective view of the main part of the pickup coil. , FIG. 17 is a sectional view taken along the line of FIG. 15, FIG. 18 is a side view of three types of iron cores, and FIG. 19 is an electric circuit diagram of the ignition system. D...Distributor,...Ignition coil, P...Pulse generator, e...Tip, 1...Housing, 72...Signal rotor, 72a...Protrusion,
79...Magnet, 80...Iron core, 80a...
Mounting plate functioning as a stopper, 81...Pickup coil, 82...Magnetic shielding plate, 82a...
Insertion hole.

Claims (1)

[Scope of utility model registration request] A pulse generator P and an ignition coil I are disposed in the housing 1 of the power distributor D, and the pulse generator P includes a signal rotor 72 having a protrusion 72a corresponding to the number of cylinders of the engine on its outer circumferential surface, An iron core 80 having a tip end e facing each protrusion 72a of the rotor 72 is wound around the iron core 80 with one end face facing the ignition coil I, and the tip e of the iron core 80 is wound on the one end face. In the ignition system for an internal combustion engine, the pickup coil 81 has a protruding pickup coil 81 and a magnet 79 coupled to the iron core 80.
2 is superimposed on the one end surface of the pick-up coil 81, and the tip e of the iron core 80 is passed through the insertion hole 82a formed at the tip of the magnetic shielding plate 82, so that it is integrally attached to the iron core 80. The formed stopper 80a is brought into contact with the other end surface of the pick-up coil 81, and the pick-up coil 8
1 is sandwiched between the stopper 80a and the magnetic shielding plate 82, and the base of the magnetic shielding plate 82 is connected to the stopper 80a.