JP2015002255A - Ignition coil for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ignition coil for an internal combustion engine which has a simple and compact configuration and furthermore made to have a wiring structure of a coil winding prevented from being loosened.SOLUTION: In an ignition coil 10 for an internal combustion engine, an electrode body electrically connected to a coil winding 212a, a first structure part 221 in which the electrode body is arranged, and a second structure part 222 which has a tension adjustment function of the coil winding 212a, are arranged collectively at portions closely approaching each other. So, all these configurations can be formed to be compact.

Description

  The present invention relates to an ignition coil for an internal combustion engine, and more particularly to a structure for arranging coil windings.

  For example, Japanese Patent Laying-Open No. 2005-005411 (Patent Document 1) introduces a terminal structure of a coil bobbin. The bobbin includes a metal electrode body, and a coil winding is wound around and fixed to the binding portion of the electrode body (FIG. 1, Patent Document 1, left end side of the coil bobbin). In addition, the electrode body is formed with a sandwiching portion in a portion different from the binding portion, and is electrically connected to an appropriate circuit configuration via this.

JP-A-2005-005411

  However, according to the technique of Patent Document 1, since the connection structure with the coil winding is formed using a metal electrode body, the configuration of the coil body becomes complicated due to the presence of the electrode body. Moreover, since the said electrode body is formed in the site | part from which a binding part and a clamping part differ, it will cause complication and enlargement of electrode body itself. Furthermore, when wiring the end portions of the coil windings, it is necessary not only to provide the electrode body with a simple configuration but also to apply a moderate tension to the windings to prevent winding slack.

  The present invention has been made in view of the above problems, and an object thereof is to provide an ignition coil for an internal combustion engine that has a simple and compact configuration and that has a coil winding arrangement without winding slack.

In order to solve the above problems, the present invention has the following configuration of an ignition coil for an internal combustion engine. That is, the coil winding wound around the neutral axis of the iron core to generate a magnetic flux change, and the wiring portion that is arranged at the winding end of the coil winding and deviates from the winding portion is fixed. An insulating frame body,
The insulating frame body is arranged at a position offset from the neutral axis, and a first structure part provided with a fixed support part that fixes a part of the wiring part, and the wiring part among the first structural part And a second structure portion that contacts a midway portion of a section from the fixed support portion to the winding portion.

  Preferably, each of the first structure portion and the second structure portion is a substantially columnar body, and each of the first structure portion and the second structure portion is arranged with a space therebetween, and is formed at the first structure portion. The portion has a maximum reachable dimension toward the nearest ridge side longer than the second end portion formed in the second structure portion.

  Preferably, the iron core forms an insulating structure with the coil winding by an insulating layer formed on a surface of the iron core and the insulating frame body. More preferably, the insulating layer is formed of an insulating tape.

  Preferably, in the second structure portion, a notch portion is formed at a position facing the wiring portion, and an intermediate contact portion is provided by the formation surface of the notch portion and the wiring portion.

  More preferably, the intermediate contact portion is disposed between the coil contact portion provided to the routing portion and the fixed support portion, includes the coil contact contact portion and the fixed support portion, and is parallel to the neutral axis. Suppose that it is arrange | positioned in the area | region of the nearest heel side direction with respect to a 1st virtual surface.

  More preferably, the intermediate contact portion is disposed between the coil contact portion and the fixed support portion, includes a coil contact contact portion and the fixed support portion, and includes a second perpendicular to the first virtual plane. It is assumed that it is arranged in the area near the iron core end with respect to the virtual plane.

  According to the ignition coil for an internal combustion engine according to the present invention, the electrode body that is electrically connected to the coil winding, the first structure portion that arranges the electrode body, and the second structure portion that bears the tension adjustment function of the coil winding are provided. Since all the components are arranged in close proximity to each other, all these configurations can be made compact.

  Here, since the frame body provided with the first structure portion and the second structure portion is accompanied by other functional portions required for the coil body, simplification of the components of the coil body is facilitated. It is done.

The figure which shows the internal structure of the ignition coil for internal combustion engines which concerns on embodiment. The figure which shows the completed body of the ignition coil for internal combustion engines which concerns on embodiment. The figure which shows the structure of the coil body which concerns on embodiment The neutral-axis direction arrow directional view of the coil body which concerns on embodiment. FIG. 3 is a view from the arrow side direction of the coil body according to the embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1 (step 1), an internal combustion engine ignition coil (hereinafter referred to as an ignition coil) according to the present embodiment includes a coil body 210 and a high-pressure structure 130, which are assembled.

  In the coil body 210, an insulating layer 215 is laminated on an I-shaped iron core 211, and a primary coil 212 is wound around the insulating layer. The coil body 210 has a frame body 220 fitted to the end of the I-shaped iron core 211. In the frame body 220, the first structure portion 221 and the like are wound with the winding of the primary coil, and an electrode body is formed at this portion. A permanent magnet 214 is provided at the opening of the frame body 220 to adjust the saturation value of the magnetic flux.

  In the high-voltage structure 130, a bobbin body 120 around which a secondary coil is wound is accommodated in a main structure part 131, and a half body part of the bobbin body 120 is covered with a head cover 110. As shown in the figure, outside the high-pressure structure 130, when the bobbin body 120 is covered, an insertion hole 121 is formed by the bobbin body 120.

  On the other hand, inside the high-pressure structure 130, a predetermined gap is formed by the secondary coil and bobbin body 120 and its outer peripheral structure (inner wall of the main structure portion and the head cover), where an insulating resin (epoxy resin or the like) is formed. 140) is impregnated. In addition, inside the high voltage structure 130, the output end of the secondary coil is conducted to a high voltage terminal (not shown), and this high voltage terminal is electrically connected to the spark plug via a high voltage tower (not shown). Done.

  In the high-voltage structure 130, the coil body 210 is inserted into the insertion hole 121 of the secondary bobbin 120, whereby the primary coil 212 is coaxially disposed on the inner peripheral portion of the secondary coil. More specifically, a structure of “I-shaped iron core 211 → insulating layer 215 → primary coil 212 → secondary bobbin 120 → secondary coil → epoxy resin → head cover 110” is formed from the neutral axis side of the iron core. .

  In step 2, the outer peripheral core parts 320 and 330 (second iron core parts) are mounted on the previous assembly to form a coil assembly (a structure comprising a primary coil, a secondary coil, and an iron core). In the coil assembly according to the present embodiment, the I-shaped iron core 211 is arranged inside the windings of both coils, and the outer peripheral iron core portions 320 and 330 are arranged so as to be connected to both ends of the iron core 211, respectively. .

  In the coil assembly, a closed magnetic path that passes through the I-shaped core 211 is formed with the outer peripheral core portions 320 and 330. That is, in the coil assembly, when the passing current in the primary coil 212 changes, a high-density magnetic flux is changed and generated in the closed magnetic circuit, and an induced electromotive force is output from the secondary coil.

  FIGS. 2A and 2B show the structure of the head cover 230. Insulating resin (PBT, PPS) is used as the material of the head cover 230, but a magnetically permeable compound may be contained therein to form a closed magnetic circuit of the coil assembly. As shown in the drawing, the head cover 230 is a shell-like body having a predetermined opening, and a flange portion 232 is integrally formed. The flange portion 232 has a bush 233 embedded therein, and is fixed to the engine head or the like through the bush 233.

  The head cover 230 is provided with a connector 234 and is electrically connected to a part such as an igniter 240 and a coil winding terminal via a connector terminal 244. In the present embodiment, a power supply terminal, a GND terminal, a signal terminal, and the like are provided as the connector terminal 244, and these are connected to the in-vehicle ECU via a harness (not shown).

  In step 3 (see FIG. 2C), the head cover 230 is attached to the high-pressure structure 130, and the inside is filled with an insulating epoxy resin and cured. In such a process, an insulating structure (a structure made of an epoxy resin) is formed in a gap such as the periphery of the high-pressure structure 130 in the head cover and the periphery of the central core body 210.

  With reference to FIG. 3, the structure of the coil body 210 which concerns on this Embodiment is demonstrated concretely. As described above, the coil body 210 according to the present embodiment forms a primary coil, and includes an I-shaped iron core 211, a coil winding 212 of the primary coil, a permanent magnet 214 for adjusting a saturation value, The insulating layer 215 and the insulating frame body 220 are configured.

  The I-shaped iron core 211 is made of a laminated steel plate, a wire element steel material, a dust material, or the like, and is composed of a material having high magnetic permeability. The material used for this is a known alloy for transformers and the like, and in this embodiment, it is assumed to be a steel alloy containing several percent of silicon.

  The insulating layer 215 is laminated around the neutral axis of the I-shaped iron core 211 with a predetermined thickness on the surface of the iron core. In particular, the insulating layer 215 according to the present embodiment uses an insulating tape in which an adhesive material is formed on one surface, and this is wound around a neutral axis so that it has a desired thickness and a desired range. An insulating part is formed. As a result, the insulating layer 215 is manufactured by an easy and simple method.

  The insulating frame body 220 is a frame-shaped body having a substantially rectangular opening, and is formed from a resin material having an insulating function. The insulating frame 214 is formed by integrating the above-described frame-like body, the first structure portion 221 provided symmetrically in two corners, and the second structure portion 222 provided corresponding to each of them. Is formed.

  The insulating frame body 220 is fitted to the nose side of the I-shaped iron core 211 (the side on which the permanent magnet 214 is disposed). The direction toward the nose side along the neutral axis CL is the iron core end direction closest to the insulating frame body 220. Further, the direction facing the side surface (the buttock) of the head cover 230 means the nearest heel side direction observed from the iron core portion facing the buttock. Here, the term “nearest iron core direction” or “nearest heel side direction” is used in order not to imply a direction opposite to the direction. Hereinafter, based on this, the nearest iron core end direction is simply referred to as “iron core end direction fx”, and the nearest iron side direction is simply referred to as “coil side direction fy”. However, the heel side direction for the structure portion on the right side of the drawing with respect to the neutral axis CL means the direction of the arrow fy shown in FIG. On the other hand, the heel side direction from the neutral axis CL to the left side of the drawing means the opposite direction of the arrow line direction in FIG. Furthermore, the direction fz in which the spark plug (not shown) is arranged is referred to as a plug direction. In the figure, the directions fx, fy, and fz are perpendicular to each other.

  According to the present embodiment, both of the structural portions 221 and 222 are provided substantially in parallel so that each has a substantially prismatic shape and is disposed with a gap therebetween. Such structure portions 221 and 222 are formed so as to extend along the heel side direction fy. Therefore, such a structure is advantageous in bridging the structure and winding the winding.

  In addition, the first structure portion 221 has an end portion (first end portion) formed on the first structure portion 221 in comparison with an end portion (second end portion) formed on the second structure portion 222. Projecting in the direction fy. That is, when measured from a reference point on the axis along the heel side direction fy, the end of the structure portion 221 has a longer maximum reachable dimension in the heel side direction fy than the end of the structure portion 222. According to this, in the surplus part of the maximum reachable dimension in the first structure part 221, the second structure part 222 does not reach the periphery of the surplus part. Processing is easy.

  With the configuration of the insulating frame body 220, the coil winding 212 has the wiring portion 212 c wired away from the winding portion 212 a and is fixed by being entangled with the first structure portion 221. At this time, an electrode body is formed by the binding portion of the first structure portion 221 or the conductive wire portion bridged by the first structure portion 221 and the second structure portion 222. That is, according to the present embodiment, the electrode body can be formed simply and easily using the coil winding 212 itself.

  In particular, the first structure portion 221 according to the present embodiment is disposed at a position that is offset from the neutral axis CL (the reverse direction of fz), and is fixed by binding a part of the routing portion 212c. A fixed support 212d is arranged. According to this, the electrode body formed around the first structure portion can be easily connected to a circuit configuration such as a connector electrode terminal or an igniter terminal by setting an appropriate distance from the neutral axis CL.

  In addition, the second structure portion 222 according to the present embodiment is arranged so as to be in contact with somewhere in the middle of the routing section (section of the winding routing path from the fixed support portion 212d to the winding portion 212). The According to this, since the winding (the routing portion 212c) is routed so as to bypass the path compared to the case where the second structure portion 222 is not provided, the loosening of the coil winding 212a can be eliminated. it can.

  As mentioned above. According to the ignition coil 10 using this, the electrode body that is electrically connected to the coil winding 212a, the first structure portion 221 that arranges the electrode body, and the second structure portion 222 that performs the tension adjustment function of the coil winding 212a, , Are arranged in close proximity to each other, so that all these configurations can be made compact.

  In addition, in the coil body 210 according to the present embodiment, an insulating structure with the coil winding 212 is formed by a composite of the insulating layer 211 and the insulating frame body 220. Further, in the present embodiment, the insulating frame body 220 plays the role of a flange portion, which is the starting point of the winding of the primary winding. Thus, since the insulating frame body 220 is accompanied by other functions / structures required for the coil body, the components of the coil body can be simplified.

  In addition, in the second structure portion 222, a notch 222a is formed at a position facing the wiring portion 212c, and a winding (a predetermined portion of the wiring portion 212c) contacts this. That is, the second structure portion 222 is provided with a contact portion (intermediate contact portion) between the formation surface of the notch portion 222a and the wiring portion 212c, whereby the winding (routing portion 212c) is securely gripped. The tension at this portion is suitably maintained. This will be described in detail with reference to FIGS. 4 and 5.

  Fig.4 (a) is the figure which observed the coil body 210 from the iron core end direction. As shown in the figure, the first structure portion 221 is provided with a first contact portion p1 where the winding and the structure portion 221 come into contact with each other at the winding portion of the fixed support portion 212d. Moreover, the intermediate contact part p2 is given to the 2nd structure part 222 in a contact location with the coil | winding (arrangement site | part 212c). Moreover, in this Embodiment, when a coil | winding (routing site | part 212c) contacts the frame-shaped body of the insulating frame 220, the coil contact part p3 is given as this contact location.

  Here, for convenience of the following description, a virtual surface including the coil contact portion p3 and the first contact portion p1 and parallel to the neutral axis CL is defined as a first virtual surface Byz (see FIG. 4B). A region in the heel side direction divided by the virtual surface Byz is defined as a region a2, and a region provided on the symmetric side of the virtual surface Byz as viewed from the region a2 is defined as a region a1.

  The intermediate contact portion p2 is disposed between the routing paths connecting the coil contact portion p3 and the first contact portion p1 (see FIG. 4A). Further, the intermediate contact portion p2 is laid out in the heel side direction fy from the first virtual surface Byz, that is, in the region a2 (see FIG. 4B). This situation means that the contact point p2 is pushed in the heel side direction fy by the reaction force received from the surface Szx of the notch 222a, and the tension of the winding at this part is suitably maintained. Further, as shown in FIG. 4 (a), the winding related to this routing section is prevented from sliding in the "reverse direction of the heel side direction fy" by the surface Szx of the notch 222a. It is possible to prevent the winding portion 212a wound spirally from being loosened.

  FIG. 5A is a view of the coil body 210 observed from the heel side direction. As illustrated, the first contact portion p1 is in contact with the corner portion of the structure portion 221 inside the winding. Further, it is understood that the coil contact portion p3 is a contact portion between the edge of the insulating frame body 220 and the winding (the wiring portion 212c). Moreover, the intermediate contact part p5 in the same figure is a point which contacts a coil | winding about the neutral-axis direction of the notch part 222a. That is, a plurality of intermediate contact portions may be formed according to the surface shape of the notch 222a, which is the case this time.

  In the coil winding 212, a second layer winding 212f is wound on a first layer winding 212e. Among these, the winding part which contacts the insulating frame body 220 is called a winding end part. In the present embodiment, the winding end portion abuts on the boss portion 223 of the insulating frame body 220, and the winding deviates from here to form the wiring portion 212c. Here, the boss portion 223 of the insulating frame body 220 can adjust the position of the coil contact portion p3 in the fz direction by changing the plate thickness dimension in the iron core end direction fx.

  For convenience of description in FIG. 5, a virtual surface including the coil contact portion p3 and the first contact portion p1 and perpendicular to the first virtual surface Byz is defined as a second virtual surface Bzx (FIG. 5B). The region in the iron core end direction fx divided by the virtual surface Bzx is referred to as a region a4, and the region given to the symmetric side of the virtual surface Bzx when viewed from the region a4 is referred to as a region a3.

  As shown in FIG. 5B, the intermediate contact portion p5 is disposed between the routing paths connecting the coil contact portion p3 and the first contact portion p1. Further, the intermediate contact portion p5 is laid out in the core end direction fx, that is, in the region a4 with respect to the first virtual surface Bzx. This situation means that the contact point p5 is pushed out toward the core end direction fx by the surface of the notch 222a, and the tension of the winding at this portion is suitably maintained. That is, in the present embodiment, it can be seen that the tension is more suitably maintained in combination with the situation in FIG. Further, as shown in FIG. 5 (a), the winding of this wiring section is prevented from being displaced in the "reverse direction of the iron core end direction fx" by the surface of the notch 222a. It is possible to prevent the winding portion 212a wound spirally from being loosened.

  Although the present embodiment has been described above, the meanings of the terms described in the claims are not limited thereto. For example, in the present embodiment, the coil body relates to the primary coil, but the present invention can also be applied to a coil body in which a secondary coil is wound.

  In the present embodiment, the coil contact portion is point p3, but this is only one form of the contact portion. For example, if the coil contact portion p3 does not exist, the point p4 that is the contact portion between the insulating tape 215 and the winding is the coil contact portion in the claims.

  10 ignition coil for internal combustion engine, 210 primary coil body, 211 iron core, 212 coil winding, 212a winding part, 212b winding end part, 212c wiring site, 212d fixed support part, 215 insulating tape, 220 insulating frame body, 221 1st structure part, 222 2nd structure part, 222a notch part, Lc neutral axis, fx nearest iron core end direction, fy nearest heel side direction, fz plug direction, p1 fixed support part, p2 intermediate contact part, p3 coil Near contact part, p5 intermediate contact part, Fyz first imaginary plane, Fzx second imaginary plane, a2 area near the heel side, a4 area near the core end.

Claims (7)

A coil winding wound around a neutral axis of the iron core to generate a magnetic flux change, and an arrangement site out of the winding portion of the coil winding fixed at the winding end of the coil winding is fixed. An insulating frame body,
The insulating frame body is arranged at a position offset from the neutral axis, and a first structure part provided with a fixed support part that fixes a part of the wiring part, and the wiring part among the first structural part An ignition coil for an internal combustion engine, comprising: a second structure portion that contacts an intermediate portion of a section extending from the fixed support portion to the winding portion.   The first structure portion and the second structure portion are each substantially columnar and each of them is arranged at an interval, and the first end portion formed in the first structure portion is: 2. The ignition coil for an internal combustion engine according to claim 1, wherein a maximum reachable dimension toward the nearest heel side direction is longer than a second end portion formed in the second structure portion.   3. The internal combustion engine according to claim 1, wherein the iron core is formed with an insulating structure with the coil winding by an insulating layer formed on a surface of the iron core and the insulating frame body. Ignition coil for engine.   The ignition coil for an internal combustion engine according to claim 3, wherein the insulating layer is formed of an insulating tape.   The second structure part is characterized in that a notch is formed at a position facing the cabling part, and an intermediate contact part is provided by the forming surface of the notch and the cabling part. The ignition coil for an internal combustion engine according to any one of claims 1 to 4.   The intermediate contact portion is disposed between the coil contact portion provided to the routing portion and the fixed support portion. The intermediate contact portion includes the coil contact contact portion and the fixed support portion and is parallel to the neutral axis. 6. The ignition coil for an internal combustion engine according to claim 5, wherein the ignition coil is disposed in a region in the nearest heel side direction with respect to the virtual plane.   The intermediate contact portion is disposed between the coil contact portion and the fixed support portion, includes the coil contact contact portion and the fixed support portion, and is provided on a second virtual surface perpendicular to the first virtual surface. On the other hand, the ignition coil for an internal combustion engine according to claim 6, wherein the ignition coil is disposed in a region near the end of the iron core.

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