JP2007194364A - Ignition coil for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition coil for internal combustion engines which is simple-structured but can achieve a reliable coupling between each of split members of an iron core. <P>SOLUTION: The ignition coil for internal combustion engines at least comprises the iron core, a coil, and a coil holder. The iron core consists of a center iron core, and side iron cores which are so called due to the layout by magnetic coupling of a plurality of divided split members of the iron core. The coil consists of a primary coil and a secondary coil which are wound sequentially on the outer perimeter of the center iron core portion of the iron core. The core holder positions and holds at least the plurality of split members of the iron core. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ignition coil for an internal combustion engine, and more particularly to an ignition coil for an internal combustion engine for supplying a high voltage for generating spark discharge to an ignition plug of the internal combustion engine.

  In such an ignition coil for an internal combustion engine, the iron core has a rod-like portion (referred to as a center iron core portion) around which a primary coil and a secondary coil are sequentially wound, and both ends of the rod-like portion are integrally attached to the primary coil. And it has the shape which has the cyclic | annular part (it calls a side iron core part) arrange | positioned so that a secondary coil may be enclosed.

  And, in order to arrange the primary coil and the secondary coil formed in a separate process from such an iron core through the center iron core in the side iron core, the iron core is divided into two or three divided members. Usually, it is constituted by a combination of these.

  For this reason, in the coupling of the separation members of the iron core when the primary coil and the secondary coil are assembled, in order to give reliability to the coupling, for example, as disclosed in the following Patent Document 1, so-called The thing using a caulking structure has come to be known.

That is, a convex portion extending in one direction is formed on one coupling surface of the coupling surfaces of each separation member of the iron core, and a concave portion extending in the same direction is formed on the other coupling surface, The concave portion is fitted and crimped by press fitting. The convex portion or the concave portion can be formed, for example, by punching with a press die.
JP 2000-294436 A

  However, it has been pointed out that the ignition coil for an internal combustion engine having the above-described configuration is difficult to accurately form the convex portions and the concave portions when the ignition coil itself is downsized. Even if the convex portion and the concave portion are accurately formed, a gap (gap) is generated in the fitting portion due to insufficient press-fitting at the time of fitting or misfit of each separating member. As engine ignition coils, it has been pointed out that performance degradation or performance variation occurs.

  The present invention has been made based on such circumstances, and the object thereof is an internal combustion engine capable of achieving a reliable connection in the mutual connection of the separation members of the iron core despite the simple configuration. It is to provide an ignition coil for an engine.

   Of the inventions disclosed in this application, the outline of typical ones will be briefly described as follows.

(1) An ignition coil for an internal combustion engine according to the present invention includes, for example, at least an iron core, a coil, and a core holder,
The iron core has a center iron core portion and a side iron core portion by arrangement by magnetic coupling of a plurality of divided members divided,
The coil has a primary coil and a secondary coil that are sequentially wound around the outer periphery of the center core portion of the iron core,
The core holder is characterized in that at least a plurality of separating members of the iron core are positioned and supported.

(2) In the ignition coil for an internal combustion engine according to the present invention, for example, on the premise of the configuration of (1), the side core portion of the iron core is formed in an annular shape and the center core portion is formed in a rod shape,
Both ends of the center iron core are magnetically coupled to the inner surface of the side iron core, and the primary coil and the secondary coil are positioned between the side iron core on both sides in the longitudinal direction. Is maintained inside the side iron core,
One end of both ends of the center core portion is formed in a divergent shape toward the end surface side, and is in contact with the inner side surface of the side core portion via a magnet.
The side core portion is divided into two at one end side of the center core portion, and is constituted by a combination of a first separation member having a large peripheral length and a second separation member having a small peripheral length. To do.

(3) The ignition coil for an internal combustion engine according to the present invention, for example, on the premise of the configuration of (2), the division of the first separation member and the second separation member of the side iron core portion is the thickness direction of the side iron core portion. It is characterized by being made at an angle with respect to.

(4) An ignition coil for an internal combustion engine according to the present invention is configured so that, for example, on the premise of the configuration of (2), the core holder can position and support a holder for a primary coil around which the primary coil is wound. And
At least a side wall portion disposed substantially parallel to the longitudinal direction of the center core portion of the iron core, and each side portion of the side wall portion in a direction orthogonal to the longitudinal direction of the center core portion is external to the center core portion. Each frame body portion extending in the direction,
The outer wall surface of the side wall portion is brought into contact with the inner wall surfaces of the first separation member and the second separation member by the arrangement of the first separation member and the second separation member of the side iron core portion,
In addition, the position of the frame body part is restricted with respect to a direction perpendicular to the longitudinal direction of the center core part of the first separation member and the second separation member of the side iron part.

(5) In the ignition coil for an internal combustion engine according to the present invention, on the premise of the configuration of (4), a convex portion extending in the longitudinal direction of the center core portion of the iron core is formed on the outer wall surface of the side wall portion. It is characterized by.

(6) In the ignition coil for an internal combustion engine according to the present invention, on the premise of the configuration of (4), the first separating member of the side core portion of the iron core is disposed on the surfaces of the frame portions facing each other. Protrusions having a substantially triangular shape having a gentle slope in the side direction are arranged in parallel along the longitudinal direction of the center core portion of the iron core.

(7) An ignition coil for an internal combustion engine according to the present invention, on the premise of the configuration of (4), the shape of at least one of the frame body portions is a combination of the first separation member and the second separation member. It is characterized by having an annular shape substantially the same as the annular side iron core portion.

  In addition, this invention is not limited to the above structure, A various change is possible in the range which does not deviate from the technical idea of this invention.

  In the internal combustion engine ignition coil configured as described above, at least each of the plurality of separation members of the iron core is positioned and supported by the core holder. For this reason, it is not necessary to employ the caulking structure as described above for each of the iron cores that are separated from each other, and therefore the iron core separation members can be reliably coupled to each other despite the simple structure. .

  Embodiments of an ignition coil for an internal combustion engine according to the present invention will be described below with reference to the drawings.

"overall structure"
FIG. 5 is a schematic configuration diagram showing an embodiment of an ignition coil for an internal combustion engine according to the present invention.

  First, there is an iron core 1, and this iron core 1 has a center iron core portion 1 a and a side iron core portion that is in direct contact with one end of the center iron core portion 1 a via a magnet (permanent magnet) 2 and directly on the other end side. 1b. As will be apparent from the following description, the center portion 1a has a rod shape, whereas the side iron core portion 1b has an annular shape, and the center portion 1b is divided into two regions within the annular shape of the side iron core portion 1b. The part 1a is arranged.

  A bobbin 3 for a primary coil disposed by inserting the center core 1a is attached to the center core 1a of the iron core 1, and a primary coil 4 is wound around the bobbin 3. Further, a secondary coil bobbin 5 disposed by inserting the primary coil 4 is attached to the primary coil 4, and a secondary coil 6 is wound around the bobbin 5.

  From this, the primary coil 4 and the secondary coil 6 are both disposed around the center core portion 1a of the iron core 1 and positioned within the side iron core portion 1b of the iron core 1 arranged so as to surround the circumference. It is like that.

  In the primary coil 4, enamel wires having a wire diameter of about 0.3 to 1.0 mm are wound around the bobbin 3 over several tens of times per layer over about 100 to 200 layers. The secondary coil 6 is wound around the bobbin 5 by dividing an enameled wire having a wire diameter of about 0.03 to 0.1 mm and extending about 5000 to 20000 times.

  Although the coil 10 configured in this manner is not shown in FIG. 5, the side iron core portion 1b of the iron core 1 is constituted by a combination of two divided iron cores. Each of the center iron core 1a, the magnet 2, the primary coil bobbin 3, the primary coil 4, the secondary coil bobbin 5, and the secondary coil 6 together with the side iron core 1b configured as described above is provided. The position is regulated and held by a coil holder (not shown) (for example, indicated by reference numeral 20 in FIG. 3), and they are handled as a coil 10 integrated with the coil holder.

  The coil 10 is housed in a case 7 formed by molding synthetic resin, and one end of the primary coil 4 is connected to a terminal 8 (for example, a terminal connected to a battery) attached to a part of the case 7. In addition, one end of the secondary coil 6 is connected to a high voltage terminal 9 attached to the other part of the case 7.

  The case 7 is filled with the epoxy resin 11 so that each connection portion of the coil 10 and the terminal 8 and the high voltage terminal 9 connected to the coil 10 is embedded in the epoxy resin 11. It has become.

  The internal combustion engine ignition coil configured as described above is connected to the center electrode of the spark plug through the high-voltage terminal 9 via a spring (not shown), a radio noise prevention resistor, a spring, and the like. These spring, radio noise prevention resistor, spring, and spark plug are disposed in a hole formed in the cylinder body of the engine, and the center electrode of the spark plug is disposed in the combustion chamber together with the ground electrode.

《Iron core》
FIG. 2A is a perspective view showing only the iron core 1 taken out from the ignition coil for the internal combustion engine, and FIG. 2B is a view showing the iron core 1 connected by, for example, three divided members. It is a perspective view which shows having comprised.

  First, as shown in FIG. 2 (a), the iron core 1 surrounds the center iron core portion 1a by contacting the center iron core portion 1a positioned at the center thereof and each surface of both ends of the center iron core portion 1a. The center core portion 1a and the side core portion 1b constitute a so-called closed magnetic path.

  The center iron core portion 1a has a rod-like shape, and a cross section perpendicular to the axial direction has a rectangular shape, for example, and the cross section at one end surface of both end surfaces in contact with the side iron core portion 1b is larger than the other cross section. Is widely formed.

  In other words, the one end portion 1e of the center iron core portion 1a is widened toward the end surface. Thus, although it is not illustrated that the area of the end surface 1e of the center core portion 1a is increased, the one end portion 1e of the center core portion 1a, the side core portion 1b, This is because a relatively thin plate-like magnet 2 (not shown) is interposed between the magnet 2 and the contact area between the magnet 2 and the end face of the center core portion 1a as much as possible.

  The side iron core portion 1b has a rectangular shape with rounded corners, for example, and is configured as a cylindrical body having a vertical axis passing through the center of the rectangle as a central axis. The cylindrical body is relatively thin, and the width in the direction along the central axis is configured to be larger than the thickness of the center iron core portion 1a in the same direction. As described later, the width of the side iron core portion 1b made of the cylindrical body in the direction along the central axis is larger than the thickness of the center iron core portion 1a in the same direction, as described later. When the bobbin 3 around which the coil 4 is wound and the bobbin 5 around which the secondary coil 6 is wound are inserted and arranged in the center core part 1a, the outer peripheral part of the secondary coil 6 is the side iron core of the iron core 1. This is to prevent the protrusion from protruding from the portion 1b or even if it protrudes.

  The center core portion 1a is disposed with a gap GP between the center core portion 1a and the side core portion 1b on both sides in the longitudinal direction, and is wound around the outer periphery of the center core portion 1a in the gap GP. The primary coil 4 and the secondary coil 6 can be arranged.

  Then, as shown in FIG. 2B, the side iron core portion 1b having a substantially rectangular shape as described above is divided at a portion that is biased toward one side thereof. It is composed of members 1b (1) and 1b (2) which are separated from each other so that the shape is a “C” and the other is substantially an “I” shape. Here, the member 1b (1) and the member 1b (2) may be referred to as a first separating member having a large peripheral length and a second separating member having a small peripheral length, respectively, in this specification.

  The dividing portion of the side core portion 1b is formed, for example, at the end opposite to the end portion 1e that is widened toward the end of the center core portion 1a, and the dividing direction of the dividing portion is the meat of the side core portion 1b. It has a relatively large angle with respect to the thickness direction. The reason for making the dividing direction of the dividing portion in this way is to make the area at the joint 1j between one end and the other end of the dividing portion as large as possible. Further, the side iron core portion 1b is divided by, for example, both ends of the second separating member 1b (2) at the dividing portion inside the both ends of the dividing portion of the first separating member 1b (1) (on the side iron core portion 1b). (Center axis side). As will become clear later, this is because the effect of position restriction in the arrangement of the second separating member 1b with respect to the core holder 20 is to be reliable.

  Each of the center core portion 1a and the side core portion 1b is configured by laminating silicon steel plates having a thickness of, for example, 0.2 to 0.5 mm in the direction of the central axis of the side core portion 1b.

《Core holder and bobbin》
FIG. 3 is a perspective view showing the bobbin 3 for the primary coil and the core holder 20 taken out from the ignition coil for the internal combustion period. FIG. 3A is a perspective view at a stage before the bobbin 3 is positioned at the fixed position with respect to the core holder 20. FIG. 3B is a perspective view when the bobbin 3 is positioned at a fixed position with respect to the core holder 20, and is a perspective view seen from the direction of arrow B in FIG. FIG. 3C is a perspective view of the core holder 20 before the bobbin 3 is positioned at the fixed position, and is a perspective view seen from the direction of the arrow C in FIG.

  First, as shown to Fig.3 (a), the bobbin 3 is comprised, for example from the thermoplastic synthetic resin, and has the cylinder part 3a in which the surface orthogonal to the axial direction makes a rectangle.

  The center core portion 1a of the iron core 1 is arranged inside the cylindrical body portion 3a of the bobbin 3 by being inserted.

  Flange portions 3b and 3c are formed at the respective end portions of the cylindrical body portion 3a of the bobbin 3, and when the center core portion 1a of the iron core 1 is disposed in the cylindrical body portion 3a of the bobbin, the center core portion A flange portion 3b is formed on the end 1e side of the end portion 1a, and a flange portion 3c is formed on the opposite end surface side.

  The flange portion 3b extends in the vertical direction (in the direction of the central axis of the side core portion 1b of the iron core 1) when viewed from the end face side of the bobbin 3 on which the flange portion 3b is formed (see FIG. 3A). And a portion 3d that extends and bends toward the front side (side iron core portion 1b side of the iron core 1), and the flange portion 3c is viewed from the end face side of the bobbin 3 on which it is formed. In this case (see FIGS. 3A and 3B), it has an annular shape extending in the vertical and horizontal directions surrounding the end face.

  The flange portions 3b and 3c of the bobbin 3 serve as guide members for guiding the bobbin 3 to a fixed position in the core holder 20 when the bobbin 3 is assembled to the core holder 20 described below, or the bobbin 3 is used as the core holder 20 It functions as a locking member or the like when guided to the fixed position. Therefore, the functions of the flange portions 3 b and 3 c of the bobbin 3 will be described in the description of the configuration of the core holder 20.

  The core holder 20 is formed of, for example, a thermoplastic synthetic resin similarly to the bobbin 3, and the side iron core portion 1b (the first separating member 1b (1) and the second separating member 1b excluding the center iron core portion 1a of the iron core 1). (2) and an annular lower frame body portion 20a having substantially the same shape as the frame shape, and substantially the same shape as the lower frame body portion 20a, but notched at some points. An upper frame body portion 20b having a portion formed thereon, and a side wall portion 20c for connecting the lower frame body portion 20a and the upper frame body portion 20b, and the lower frame body portion 20a and the upper frame body portion 20b as an end face as a whole. It is grasped as a substantially cylindrical member on the side.

  It should be noted that the upper frame body portion 20b has a part cut out at a part thereof when the bobbin 3 is assembled into the core holder 20, in this embodiment, the bobbin 3 is directed upward (side iron core portion 1b). This is to prevent the bobbin 3 from interfering with the upper frame body 20b at this time.

  The side wall portion 20c is formed so as to be positioned on the inner side of the lower frame body portion 20a and the upper frame body portion 20b (side of the iron core 1 on the side of the center core portion 1a). The body part 20a and the upper frame body part 20b are grasped as flanges extending outward with respect to the center core part 1a of the iron core 1.

  Further, assuming that the bobbin 3 is incorporated in the core holder 20, the side wall portion 20 c is connected to the portion substantially parallel to the central axis direction of the bobbin 3, and is connected to the portion of the bobbin 3. It is formed in a portion that slightly surrounds the side where the flange portion 3c is disposed. In other words, the side wall portion 20c is configured not to be formed in the vicinity of the bobbin on the side where the flange portion 3b is disposed and in the portion facing the flange portion 3c. That is, when the bobbin 3 is incorporated in the core holder 20, the flange portions 3 b and 3 c of the bobbin 3 constitute side wall portions that are formed substantially continuously with the side wall portion 20 c of the core holder 20 over one week. It is designed to be understood.

  And in each side wall part of the said side wall part 20c of the core holder 20, the edge part side of the part in which the flange part 3c of the said bobbin 3 is arrange | positioned slightly goes up and down direction (the direction of the central axis of the side iron core part 1b of the said iron core 1) ) Formed along the groove (not shown). When the bobbin 3 is assembled into the core holder 20, the grooves are the ends of the left and right sides of the flange portion 3 c of the bobbin 3 (the other two sides excluding the upper and lower sides in the central axis direction of the side core portion 1 b of the iron core 1). The bobbin 3 can be guided to the inside of the core holder 20 by abutting the side surfaces. Further, when the bobbin 3 is incorporated in the core holder 20, a portion 3d that bends and extends toward the front side in the flange portion 3b of the bobbin 3 is positioned on the upper surface of the lower frame body portion 20a. Yes.

  A claw portion 20e is implanted and formed on the back portion (inner peripheral surface side) of the lower frame body portion 20a where the flange portion 3b of the bobbin 3 is positioned. The claw portion 20e is formed when the bobbin 3 is inserted. The flange portion 3b is once bent backward by the portion 3d, but is locked by a groove or the like (not shown) formed in the back portion of the portion 3d of the flange portion 3b by the elastic force. It has become.

  As a result, the bobbin 3 is restricted in position so as to maintain its fixed position inside the core holder 20. Even if the primary coil 4 wound around the bobbin 3 and the secondary coil wound around the bobbin for the secondary coil disposed on the outer periphery of the primary coil 4 are attached to the core holder 20, This means that the position is restricted.

  Further, a convex portion 20p is formed on the outer surface of the side wall portion 20c of the core holder 20 so as to extend in parallel with the lower frame body portion 20a and the upper frame body portion 20b. As will be described in detail later, when the convex portion 20p is arranged such that the “C” -shaped side core portion 1b (1) of the iron core is in contact with the side wall portion 20c with the core holder 20 interposed therebetween, the side iron core The portion 1b (1) functions to slightly spread outward by the height of the convex portion 20p, thereby functioning to firmly hold the core holder 20 by the elastic force generated in the side iron core portion 1b (1). To do.

  Further, the lower frame body portion 20a and the upper frame body portion 20b in which the side wall portion 20c is formed have a longitudinal direction of the lower frame body portion 20a and the upper frame body portion 20b on each of their opposing surfaces. A plurality of protrusions 20q are formed side by side along the direction. Each of the protrusions 20q has, for example, a triangular shape having a gentle slope on the end 1e side of the center core portion 1a incorporated in the core holder 20 and a steep slope on the opposite side. There is no. Although these protrusions 1q will be described in detail later, when the “C” -shaped side iron core portion 1b (1) of the iron core is inserted into the core holder 20 by inserting the core holder 20 between the open ends, the core holder 20 is inserted. Further, the upper and lower end surfaces of the side iron core portion 1b (1) move while sliding on the opposing surfaces of the upper frame body portion 20c and the lower frame body portion 20a, respectively, and the movement is smoothly inserted. It functions easily, and after it is fixed at a fixed position by this movement, it is difficult to pull in the opposite direction.

  4 is a block diagram showing an embodiment of the core holder 20. FIG. 4 (a) is a top view, FIG. 4 (b) is a front view, FIG. 4 (c) is a side view, and FIG. ) Shows a rear view.

  As is clear from FIG. 4, the lower frame body portion 20a and the upper frame body portion 20b of the core holder 20 both have a rectangular shape with rounded corners (edges) (R shape). Also in each side wall part 20c formed in the inner peripheral side of the lower frame body part 20a and the upper frame body part 20b, the edge part is extended and formed to the part to which the said roundness was given. For this reason, even in a core holder formed of a synthetic resin material, stress concentration can be alleviated even when subjected to external stress or thermal stress.

《Iron core, bobbin and core holder》
FIG. 1 is a perspective view showing a connection relationship between the iron core 1, the bobbin 3 for primary winding, and the core holder 20, and FIG. 1 (a) is a divergent end of the center iron core portion 1a of the iron core 1. FIG. FIG. 1B is a diagram viewed from the end portion opposite to the portion 1 e, and FIG. 1B is a diagram viewed from the end portion 1 e side of the center core portion 1 a of the iron core 1.

  Further, in FIG. 1, in order to clarify the positional relationship between the iron core 1, the bobbin 3 for the primary winding, and the core holder 20, the primary winding 4, the bobbin 5 for the secondary winding, and the secondary winding Drawing 6 is omitted.

  In FIG. 1, first, there is a bobbin 3 for primary winding. Actually, a primary winding is wound around the outer periphery of the bobbin for the primary winding, and a bobbin for a secondary winding for interpolating the primary winding is provided around the primary winding. There is a secondary winding wound around the bobbin for the secondary winding. The bobbin 3 for the primary winding is held by the core holder 20 with its position regulated. In this case, the coupling state between the bobbin 3 for primary winding and the core holder 20 is the same as described with reference to FIG.

  A center core portion 1a of the iron core 1 is inserted into the bobbin 3 for primary winding. In this insertion, the center core part 1a is inserted into the bobbin 3 for primary winding from the end part side opposite to the end part 1e having a widening end. As a result, the end wide end portion 1e of the center core portion 1a is locked on the flange 3b side of the bobbin 3, and the end surface opposite to the end wide end portion 1e is on the flange 3c side of the bobbin 3. To be positioned substantially flush with the surface of the flange 3c.

  Next, the separating member 1b (1) having a long peripheral length in the side core portion 1b of the iron core 1 is inserted into the core holder 20 by being inserted from the open end side with the core holder interposed therebetween. . The separating member 1b (1) is positioned on the end 1e side of the center iron core portion 1a, and the inner surface of the release end of the separating member 1b (1) This is done by moving the separating member 1b (1) in a state of being in contact with the side wall portion 20c of the core holder 20. In inserting the separating member 1b (1), a magnet 2 (permanent magnet) (not shown) is interposed between the end surface 1e of the center core portion 1a and the end portion 1e. . In this case, the lower frame body portion 20a and the upper frame body portion 20b of the core holder 20 function as a guide in the movement of the separating member 1b (1), and after being fixed at a fixed position (side iron core portion) 1b (in the direction of the central axis).

  The side wall portion 20c of the core holder 20 is formed with a convex portion 20p extending in the moving direction of the separating member 1b (1), and the convex portion 20p attaches the separating member 1b (1) having an open end to the separating member 1b (1). The core holder 20 can be firmly clamped by the elastic force generated in the separating member 1b (1) by acting so as to slightly expand outward by the height of the convex portion 20p.

  In consideration of the function of the convex portion 20p, the length in the longitudinal direction of the convex portion 20p is formed to be smaller than the width in the same direction of the side wall portion 20c, and each end portion in the direction of the side wall portion 20c is formed. It is advantageous to form the core holder so as to extend to the rounded corner of the core holder.

  As described above, when the end portions of the side walls 20c are extended to the rounded corners of the core holder 20, the spacing widths of the opposing side walls 20c are as described above. The separation member 1b (1) is formed to be small on the insertion side, and the release width of the release end of the separation member 1b (1) is the separation width of each side wall portion 20c (excluding the separation width at each end portion). The separation member 1b (1) can be easily inserted with the core holder 20 in between. Even if the release width of the release end of the separation member 1b (1) is slightly larger than the separation width of each side wall portion 20c (excluding the separation width at each end portion), the separation member 1b ( 1) can be inserted while being in contact with the side wall portions 20c via the convex portions.

  In FIG. 1, two protrusions 20p are formed on each side wall 20c. However, the number is not limited, and one or more than three is provided. It goes without saying.

  In addition, a protrusion 20q is formed on each of the lower frame body portion 20a and the upper frame body portion 20b in contact with the separation member 1b (1), and the protrusion 20q is formed on the separation member 1b ( 1) Since it has a triangular shape with a gentle slope in the insertion direction and a steep slope on the opposite side of the insertion direction, the insertion of the separating member 1b (1) is smooth. It is possible to make it difficult to pull in the opposite direction after it is fixed in place by this insertion.

  Further, the protrusion 20q is loosened between the lower frame portion 20a or the upper frame portion 20b due to variations in the thickness of the separating member 1b (1) (the width in the central axis direction of the side iron core portion 1b). You can also adjust what happens. As described above, the separation member 1b (1) is composed of a laminated body of silicon steel plates, for example, and the thickness of the separation member 1b (1) is likely to vary due to variations in the thickness of each silicon steel plate. It is taken into consideration.

  Then, the separating member 1b (2) is assembled into the core holder 20 in the same manner as the separating member 1b (1). In this case, since the peripheral length of the separating member 1b (2) is smaller than the peripheral length of the separating member 1b (1), the lower frame body portion 20a and the upper frame are compared with the separating member 1b (1). Each of the body part 20b and the side wall part 20c does not function greatly as a position regulating member, but a magnetic force (on the end face of the center core part 1a exposed to the flange part 3c side of the bobbin 3 for the primary coil) And both ends thereof are inserted inside the both ends of the separating member 1b (1) and are attracted.

  For this reason, consideration is given to the sufficient restriction of the position even when the separating member 1b (2) is incorporated into the core holder 20. Further, in this case, since the joining area is increased as described above at the joining portions of both ends of the separating member 1b (2) and both ends of the separating member 1b (1), Bonding can be strengthened, and the reliability of position regulation of the separating member 1b (2) to the core holder 20 can be ensured.

  Each of the embodiments described above may be used alone or in combination. This is because the effects of the respective embodiments can be achieved independently or synergistically.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of an ignition coil for an internal combustion engine according to the present invention, showing the positional relationship among an iron core, a primary winding bobbin, and a core holder used in the internal combustion engine ignition coil. 1 is a perspective view showing an embodiment of an ignition coil for an internal combustion engine according to the present invention, and is a diagram showing a configuration of an iron core used in the ignition coil for an internal combustion engine. FIG. 1 is a perspective view showing an embodiment of an ignition coil for an internal combustion engine according to the present invention, and a positional relationship between a core holder used for the internal combustion engine ignition coil and a bobbin for a primary winding, and a positional restriction of a bobbin for a primary winding with respect to the core holder; FIG. 1 is a perspective view showing an embodiment of an ignition coil for an internal combustion engine according to the present invention, and is a view showing a configuration of a core holder used in the internal combustion engine ignition coil. FIG. It is a schematic block diagram which shows one Example of the ignition coil for internal combustion engines by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Iron core, 1a ... Center iron core part, 1b ... Side iron core part, 1b (1) ... Separation member with long peripheral length, 1b (2) ... Separation member with short peripheral length, 2 ... Magnet, 3 ... Bobbin for primary coil, 3a ... Cylinder, 3b, 3c ... Flange, 4 ... Primary coil, 5 ... Bobbin for secondary coil, 6 ... Secondary coil, 7 ... Case: 8 ... Terminal, 9 ... High voltage terminal, 10 ... Coil, 11 ... Epoxy resin, 20 ... Core holder, 20a ... Lower frame body part, 20b ... Upper frame body part, 20c ... Side wall part , 20e: nail, 20p: convex, 20q: projection.

Claims (7)

Comprising at least an iron core, a coil, and a core holder,
The iron core has a center iron core portion and a side iron core portion by arrangement by magnetic coupling of a plurality of divided members divided,
The coil has a primary coil and a secondary coil that are sequentially wound around the outer periphery of the center core portion of the iron core,
An ignition coil for an internal combustion engine, wherein the core holder positions and supports at least a plurality of separating members of the iron core. The side core portion of the iron core is formed in an annular shape and the center core portion is formed in a rod shape,
Both ends of the center iron core are magnetically coupled to the inner surface of the side iron core, and the primary coil and the secondary coil are positioned between the side iron core on both sides in the longitudinal direction. Is maintained inside the side iron core,
One end of both ends of the center core portion is formed in a divergent shape toward the end surface side, and is in contact with the inner side surface of the side core portion via a magnet.
The side core portion is divided into two at one end side of the center core portion, and is constituted by a combination of a first separation member having a large peripheral length and a second separation member having a small peripheral length. The ignition coil for an internal combustion engine according to claim 1. 3. The internal combustion engine according to claim 2, wherein the first separation member and the second separation member of the side iron core portion are divided at an angle with respect to a thickness direction of the side iron core portion. Ignition coil. The core holder is configured to position and support a primary coil holder that winds the primary coil, and
At least a side wall portion disposed substantially parallel to the longitudinal direction of the center core portion of the iron core, and each side portion of the side wall portion in a direction orthogonal to the longitudinal direction of the center core portion is external to the center core portion. Each frame body portion extending in the direction,
The outer wall surface of the side wall portion is brought into contact with the inner wall surfaces of the first separation member and the second separation member by the arrangement of the first separation member and the second separation member of the side iron core portion,
The position of the frame body part is restricted with respect to a direction perpendicular to the longitudinal direction of the center core part of the first separation member and the second separation member of the side iron part. Ignition coil for internal combustion engine. The ignition coil for an internal combustion engine according to claim 4, wherein a convex portion extending in a longitudinal direction of the center core portion of the iron core is formed on an outer wall surface of the side wall portion. Each of the frame parts has a substantially triangular projection having a gentle slope in a direction in which the first separation member of the side core part of the iron core is disposed on a surface facing each other. The ignition coil for an internal combustion engine according to claim 4, wherein the ignition coil is arranged in parallel along a longitudinal direction of the internal combustion engine. The shape of at least one of the frame parts is an annular shape that is substantially the same shape as the annular side core part to which the first separation member and the second separation member are coupled. 4. An ignition coil for an internal combustion engine according to 4.

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