CN100550228C - Ignition coil and manufacture method thereof - Google Patents

Abstract

The invention provides a kind of ignition coil, not only make the insulation sheet material be difficult to come off, and can keep the insulation sheet material simply and be wrapped in state on the central core, and the winding number of times of the sheet material that can suppress to insulate increases.Ignition coil has: bar-shaped central core (3), with possessing concentric circles be wrapped in central core (3) around primary coil and the cylindrical portion of secondary coil, the sheet material (4) that will insulate is wrapped on the outer peripheral face (301) of central core (3), fills insulating resin between insulation sheet material (4) and cylindrical portion.Insulation sheet material (4) comprises by the resin thin film layer that forms with synthetic resin and is provided in the adhesive linkage at the back side of resin thin film layer.The sheet width (w) of insulation sheet material (4) be 0.8～1.2 times of axial length (x) of central core (3), and it twines terminal (42) axial (L) inclination with respect to central core (3).

Description

Ignition coil and manufacture method thereof

Technical area

The present invention relates to produce the ignition coil of spark by spark plug.

Background technology

The ignition coil that is used for producing spark in the spark plug in the engine of vehicle etc., the outer peripheral face in the central core of the interior all sides that are equipped on the coil portion that possesses primary coil and secondary coil twines the insulation sheet material as the thermal stress padded coaming.The infringement that makes the insulating resin that is filled between coil portion and the central core not caused by the heat that repetition produced of the heating cool cycles in the engine by this insulation sheet material.

The ignition coil that this sheet material that will insulate is wrapped on the central core has for example patent documentation 1～3 disclosed ignition coil.

In patent documentation 1, between central core and secondary winding (being wound with the bobbin of secondary coil), accompany the insulation sheet material.Therefore, even in the secondary winding that forms with thermoplastic resin, produce bubble etc., also can guarantee electrical insulating property between central core and the secondary coil by the insulation sheet material.

And, in patent documentation 2, suitably set the wall thickness that is wrapped on the central core as the insulation sheet material of thermal stress padded coaming.Thus, the resin-insulated material that is filled between central core and the tubular bobbin can not cracked etc. because of thermal stress.

And, in patent documentation 3, be wrapped on the outer peripheral face of central core as the whole winding end of the insulation sheet material of thermal stress padded coaming on implement material lining (gel) etc., it is outstanding to the hole enlargement direction to prevent that above-mentioned winding end from coming off from central core.Thus, prevent that distal process goes out and it is concentrated to produce stress at this windings end because twine, and the resin-insulated material that prevents to be filled between central core and the coil portion cracks etc. because of thermal stress.

But shown in Figure 17,18, in above-mentioned ignition coil in the past, rectangular insulation sheet material 94 twines abreast with the axial L of central core 3, and the formation direction of the winding end 942 of insulation sheet material 94 is parallel with the axial L of central core 3.Therefore, the insulation sheet material 94 after the winding comes off easily, described in above-mentioned patent documentation 3, need implement material lining (gel) etc. to the winding end (twining end) 942 of whole insulation sheet material 94.

[patent documentation 1] Japanese kokai publication hei 10-92670 communique

[patent documentation 2] TOHKEMY 2004-14548 communique

[patent documentation 3] TOHKEMY 2004-111714 communique

Summary of the invention

The present invention is made in view of in the past these problems, its objective is to provide a kind of ignition coil, it can make the insulation sheet material be difficult to come off, and can keep the insulation sheet material simply and be wrapped in state on the central core, and the number of times that can also suppress to twine the insulation sheet material simultaneously increases.

First invention is a kind of ignition coil, have: bar-shaped central core, with be wound on the primary coil around this central core and the cylindrical portion of secondary coil with possessing concentric circles, on the outer peripheral face of above-mentioned central core, twine the insulation sheet material, and between this insulation sheet material and above-mentioned cylindrical portion, fill insulating resin, it is characterized in that, above-mentioned insulation sheet material comprises the resin thin film layer that is formed by synthetic resin and is provided in the adhesive linkage at this resin thin film layer back side, sheet width is 0.8 times～1.2 times of axial length of above-mentioned central core, and the end of its winding has the sloping portion with respect to the axioversion of above-mentioned central core.

Ignition coil of the present invention is provided with sloping portion by the winding end at the insulation sheet material of the outer peripheral face that is wound in central core, and manages to make the insulation sheet material to be difficult to come off.

That is, when 0.8～1.2 times of axial length the insulation sheet material that with sheet width is central core twined and bonds to the outer peripheral face of central core, the sloping portion of winding end that makes this insulation sheet material was with respect to the axioversion of central core.

Therefore, in the insulation sheet material on being wound in central core,, also can reduce this peel force even the restoring force of the strain that produces when being wound on the central core act as the power that the winding end that makes this insulation sheet material comes off.Thus, can make the winding end of insulating trip material be difficult to come off.

And,,, can keep making the insulation sheet material be wrapped in state on the central core simply so above-mentioned insulation sheet material bonding need do not carried out the fixing of other at the winding end of whole insulation sheet material because the insulation sheet material is difficult to come off.

And the sheet width of insulation sheet material is 0.8～1.2 times of axial length of central core.Therefore, need only make the Width of insulation sheet material consistent with central core, the week that the insulation sheet material is wrapped in central core abreast upwards just can cover the almost whole outer peripheral face of central core, the increase of the sheet material winding number of times that can suppress to insulate.

In addition, even at the sheet width of insulation sheet material than the axial length of central core in short-term, the part of twining the outer peripheral face of insulation sheet material also can cover with for example other structure member.And, when the sheet width of insulation sheet material is longer than the axial length of central core, can this major axis is folding to the axial end of central core to remainder.

Therefore,, not only can make the insulating trip material be difficult to come off, can also keep the insulation sheet material simply and be wound into state on the central core if adopt ignition coil of the present invention, and, the increase that the sheet material that can also suppress to insulate twines number of times.

Second invention is a kind of ignition coil, have: bar-shaped central core, with be wound on the primary coil around this central core and the cylindrical portion of secondary coil with possessing concentric circles, on the outer peripheral face of above-mentioned central core, twine the insulation sheet material, and between this insulation sheet material and above-mentioned cylindrical portion, fill insulating resin, it is characterized in that, above-mentioned insulation sheet material comprises the resin thin film layer that is formed by synthetic resin and is provided in the adhesive linkage at the back side of this resin thin film layer, under the state before being wound on the above-mentioned central core, sheet width is 0.8 times～1.2 times of axial length of above-mentioned central core, and a pair of axial end portion that is positioned at Width is parallel to each other, twines the terminal sloping portion that has with respect to above-mentioned Width inclination in the time of on being wound into above-mentioned central core.

Ignition coil of the present invention also is provided with sloping portion by the winding end at the insulation sheet material of the outer peripheral face that is wound in central core, and manages to make the insulation sheet material to be difficult to come off.

And under the state of insulation sheet material before being wound in central core among the present invention, a pair of axial end portion that is positioned at Width is parallel to each other, and has sloping portion in the end that is positioned at the winding end when being wound on the central core.Therefore, the sheet material that will insulate easily is wrapped on the central core, after the sheet material that will insulate is wound on the central core, makes easily to be positioned at the axioversion ground configuration of the terminal sloping portion of this winding with respect to central core.

In addition, action effect of the present invention is identical with above-mentioned the 1st invention.

Therefore,, also not only can make the insulation sheet material be difficult to come off, be wrapped in state on the central core but also can keep the insulation sheet material simply if adopt ignition coil of the present invention, and the sheet material that can suppress the to insulate increase of twining number of times.

The 3rd invention is a kind of manufacture method of ignition coil, this ignition coil has: bar-shaped central core, with be wound on the primary coil around this central core and the cylindrical portion of secondary coil with possessing concentric circles, on the outer peripheral face of above-mentioned central core, twine and bonding insulation sheet material, and between this insulation sheet material and above-mentioned cylindrical portion, fill insulating resin, it is characterized in that comprising: the sheet material that forms the insulation sheet material forms operation, the sheet width of this insulation sheet material is 0.8～1.2 times of axial length of above-mentioned central core, and with at least one end of the winding direction of Width quadrature on the sloping portion that tilts with respect to above-mentioned Width is set; Winding working procedure makes the Width of above-mentioned insulation sheet material consistent with the axial direction of above-mentioned central core, and this insulation sheet material is wrapped in the outer peripheral face of above-mentioned central core, and it is terminal to make the end that is provided with above-mentioned sloping portion be positioned at this winding.

The manufacture method of ignition coil of the present invention is to make the manufacture method of the ignition coil that presents above-mentioned good action effect.

That is, among the present invention, in above-mentioned formation operation, form the insulation sheet material that has above-mentioned predetermined sheet width and the sloping portion that tilts with respect to above-mentioned Width is set at least one end of above-mentioned winding direction.

And in above-mentioned winding working procedure, when the sheet material that will insulate was wound into the outer peripheral face of central core, it was terminal to make the end that is provided with above-mentioned sloping portion be positioned at this winding.

Therefore, the ignition coil of making by above-mentioned each operation can present the good action effect same with the invention of above-mentioned ignition coil.

Therefore, if adopt manufacture method of the present invention, can produce and to make the insulation sheet material be difficult to come off but also can keep simply that the insulation sheet material is wrapped in the state on the central core and the sheet material that can suppress to insulate twines the ignition coil of the increase of number of times.

Description of drawings

Fig. 1 is the cross sectional illustration figure of the ignition coil of expression embodiment 1.

Fig. 2 is that the expression sheet material that will insulate among the embodiment 1 is wrapped in the perspective illustration of the state on the central core.

Fig. 3 is that the expression sheet material that will insulate among the embodiment 1 is wrapped in the perspective illustration of the state on the central core.

Fig. 4 is the amplification perspective illustration of the winding end of the insulation sheet material under the state on the central core of being wound in of expression embodiment 1.

Fig. 5 represents the amplification profile key diagram of the periphery that is equipped on the central core in the ignition coil and the sheet material that insulate of embodiment 1.

Fig. 6 is the perspective illustration that forms the state of insulation sheet material with the cutting machine cut-out of expression embodiment 1.

Fig. 7 is that the expression sheet material that will insulate among the embodiment 2 is wrapped in the perspective illustration of the state on the central core.

Fig. 8 is that the expression sheet material that will insulate among the embodiment 2 is wrapped in the perspective illustration of the state on the central core.

Fig. 9 is the perspective illustration of the state on the central core that among the expression embodiment 2 other insulation sheet material is wrapped in.

Figure 10 is the perspective illustration of the state on the central core that among the expression embodiment 2 other insulation sheet material is wrapped in.

Figure 11 be expression embodiment 3 winding central core under the insulation sheet material state and the perspective illustration of folding anchor clamps.

Figure 12 is by will the insulate cross sectional illustration figure of the state that the outstanding end of sheet material folds to the axial end of central core of folding anchor clamps among the expression embodiment 3.

Figure 13 is that expression will be insulated the outstanding end of sheet material among the embodiment 3 to the perspective illustration of central core axial end folded state.

Figure 14 is the cross sectional illustration figure of the ignition coil of expression embodiment 4.

Figure 15 is the perspective illustration of the state on the central core that among the expression embodiment 1～4 other insulation sheet material is wrapped in.

Figure 16 is the perspective illustration of the state on the central core that among the expression embodiment 1～4 other insulation sheet material is wrapped in.

Figure 17 is illustrated in the perspective illustration that the sheet material that will insulate in the example of prior art is wrapped in the state on the central core.

Figure 18 is the amplification perspective illustration that is illustrated in the winding end of the insulation sheet material under the state that is wound in the example of prior art on the central core.

Embodiment

The following describes preferable example of the present invention.

In the present invention, when 0.8 times of the axial length of the not enough above-mentioned central core of the sheet width of above-mentioned insulation sheet material, the part of outer peripheral face of central core of twining the insulation sheet material is very wide, is difficult to other structure member covering.And when the sheet width of above-mentioned insulation sheet material surpasses 1.2 times of axial length of above-mentioned central core, then being difficult to will be folding to the axial end of central core from the part of the outstanding insulation sheet material of the axial end of central core.

And the sloping portion of the winding end of above-mentioned insulation sheet material is preferably in whole the winding on the terminal length and forms.And twining terminal sloping portion also can be in the zone formation at least 50% or more of the Width of this sheet material that insulate.That is, twine terminal sloping portion for minimum by making, and formation in 50% zone of the Width of this insulation sheet material, also can make this insulation sheet material be difficult to come off from central core.

Above-mentioned insulation sheet material preferably make its Width and above-mentioned central core axially parallel be wrapped on this central core.

At this moment, the sheet material that stably will insulate easily is wrapped on the central core.

Above-mentioned central core can stacked diametrically several piece steel plate and is formed.

When above-mentioned central core is formed by radially stacked several piece steel plate, central core axially on along the axial formation step space of steel plate and steel plate intersection.At this moment,, then twine the terminal radially displacement of step space of passing through easily, come off easily if the winding end of insulation sheet material is positioned at above-mentioned step space.

Relative therewith, at least a portion of the winding end by making above-mentioned insulation sheet material is with respect to the axioversion of central core, and at least a portion of winding end that can make the insulating trip material is with respect to above-mentioned step space sloped position.Thus, even under the situation that central core is made of radially stacked several piece steel plate, also can make the winding end of insulating trip material be difficult to come off.

Above-mentioned winding end has acute angle-shaped sheet material bight, and it is fixing that this acute angle-shaped sheet material bight prevents to come off.That is, carried out above-mentioned winding working procedure after, preferably carry out being used to preventing the fixing fixedly operation that comes off in the acute angle-shaped sheet material bight that is formed at above-mentioned winding end.

The contact area in above-mentioned acute angle-shaped sheet material bight is little, is easy to come off from shape sheet material bight, obtuse angle, can prevent to come off so carry out said fixing.And even in this case, prevent to come off fixing can be kept the sheet material that insulate simply and be wrapped in state on the central core as long as carry out just passablely in the part of the winding end of insulation sheet material.

The sloping portion of above-mentioned winding end is preferably 5 °～60 ° with respect to the axial angle of inclination of above-mentioned central core.For example, form in the operation at above-mentioned sheet material, the sloping portion of an end on the above-mentioned winding direction of above-mentioned insulation sheet material is preferably with respect to tilt 5 °～60 ° angle of inclination of the Width of above-mentioned insulation sheet material.

In these cases, the angle of inclination of twining terminal sloping portion is suitable, can further obtain the good action effect of above-mentioned ignition coil.

Under the situation of 5 ° of the angle of inclination deficiencies of the inclined end portion of sheet material, the angle of inclination is little, might be able to not obtain the good action effect of above-mentioned ignition coil.And when the angle of inclination of sheet material inclined end portion surpassed 60 °, the angle of inclination was excessive, might increase the winding number of times of insulation sheet material.

The sloping portion of above-mentioned winding end is preferably whole to tilt to same direction.That is, form in the operation, the sloping portion integral body of an end of the above-mentioned winding direction that is positioned at above-mentioned insulation sheet material is formed obliquely to same direction at above-mentioned sheet material.

In these cases, twine and terminally to form easily, just can make the winding end be difficult to come off with the insulation sheet material of simple shape.And, twine terminal sloping portion and not necessarily want linearly crustal inclination, also can be circular-arc crustal inclination.For example, the terminal axial angle of inclination with respect to central core of winding is diminished gradually to acute angle-shaped sheet material bight.

And counter-rotating in the middle of the incline direction of the sloping portion of above-mentioned winding end is preferably in is mountain shape or paddy shape.That is, form in the operation, the incline direction of the sloping portion of an end on the above-mentioned winding direction of above-mentioned insulation sheet material is reversed in the centre, be mountain shape or paddy shape at above-mentioned sheet material.

Above-mentioned winding end not only can make its whole sloping portion be formed slopely to same direction, and can be formed slopely as these situations and be mountain shape or paddy shape.At this moment, can make the winding end be difficult to come off.

And the above-mentioned sloping portion that is mountain shape or paddy shape can also can form a plurality of twining one of terminal formation.

Above-mentioned insulation sheet material is preferably under its winding state axial remainder is folding to the axial end of above-mentioned central core.That is, in above-mentioned winding working procedure, above-mentioned insulation sheet material preferably twines from the axial end of above-mentioned central core is outstanding, and is under this winding state that axial remainder is folding to the axial end of above-mentioned central core.

In these cases, can the part of the winding end of insulation sheet material is folding to the axial end of central core, the winding end of insulating trip material is not come off.

The axial both ends of above-mentioned central core can set magnet respectively and form.At this moment, the sheet width of above-mentioned insulation sheet material is preferably 0.8～1.2 times of axial length of the above-mentioned central core of the axial length that comprises above-mentioned pair of magnet.

Therefore, can make the winding end of insulating trip material be difficult to come off from the central core that is equipped with magnet respectively at axial both ends.

[embodiment]

The embodiment of ignition coil of the present invention and manufacture method thereof is described with reference to the accompanying drawings.

(embodiment 1)

As shown in Figure 1, the ignition coil 1 of present embodiment has: bar-shaped central core 3 and be wrapped in with possessing concentric circles this central core 3 around primary coil 21 and the cylindrical portion 2 of secondary coil 22, on the outer peripheral face 301 of central core 3, twine insulation sheet material 4, between this insulation sheet material 4 and above-mentioned cylindrical portion 2, fill insulating resin 5.

As shown in Figure 5, above-mentioned insulation sheet material 4 comprises resin thin film layer 45 that is made of synthetic resin and the adhesive linkage (adhesion coating) 46 that sets at these resin thin film layer 45 back sides.And to shown in Figure 4, the sheet width w of insulation sheet material 4 is 0.8～1.2 times of axial length of central core 3 as Fig. 2, and this twines the terminal 42 axial L with respect to central core 3 and tilts.

Below, this is elaborated.

As shown in Figure 1, the ignition coil 1 of present embodiment is for inserting the bar type that uses in the consent of engine with its cylindrical portion 2.

Above-mentioned cylindrical portion 2 is provided with periphery iron core 24, primary coil 21, secondary coil 22 and central core 3 at solenoid housing 20 interpolation wildcards.That is, the lead that above-mentioned primary coil 21 will be coated with insulation is wound in cylindric, above-mentioned secondary coil 22 at the outer peripheral face of secondary bobbin 221 cylindraceous with than the number of turns of primary coil more than 21 and twine the lead that is coated with insulation.And secondary coil 22 is inserted interior Monday of the side of leading to primary coil 21, interior Monday of secondary coil 22 side set bar-shaped metallic central core 3.In addition, primary coil 21 inserts in the cylindric periphery iron core 24, and this periphery iron core 24 inserts in the solenoid housing 20.

And the magnetic flux that flows through the electric current generation in primary coil 21 can increase by central core 3 and periphery iron core 24.And, set elastomeric element 321 at the axial both ends 32 of central core 3.

In addition, the permanent magnet that also can set the magnetic flux that the above-mentioned primary coil of further increase 21 produces at the axial both ends 32 of central core 3 replaces above-mentioned elastomeric element 321.

And, the primary coil 21 of present embodiment the lead of the insulation that will be covered be wound in cylindric after, the lead after will twining with deposited dose of grade be bonded to each other make cylindric.Relative therewith, primary coil 21 also can be wrapped in the lead of the insulation that has been covered the outer peripheral face of cylindric elementary bobbin.

And, fill insulating resin 5 in each slit 29 between central core 3 and secondary coil 22, between secondary coil 22 and the primary coil 21, between primary coil 21 and the periphery iron core 24.

And cylindrical portion 2 has the spark plug installing port 26 that is used to install spark plug on inserting the axial forward end portion 201 of leading in the consent that is configured to engine.On this spark plug installing port 26, be equipped with an end (end, high-pressure side) of secondary coil 22 and keep HV Terminal 27 that is electrically connected and the helical spring 28 that contacts with this HV Terminal 27.And, cylindrical portion 2 with the axial base end part 202 of axial forward end portion 201 opposite sides on have radially outwards outstanding flange part 255, on flange part 255, be formed with and be used for inserting the logical bolt insertion hole 256 that combines with engine bolt.

In addition, on the axial base end part 202 of solenoid housing 20, be formed for setting the igniter configuration recess 25 of the igniter 251 of powering to primary coil 21.And, in this igniter configuration recess 25, under the state that has set igniter 251, be filled with and the identical insulating resin 5 of insulating resin 5 that is filled between above-mentioned each slit in 29.And igniter 251 possesses the electronic control circuit that used the switch element that moves down in the effect of the signal of ECU (electronic control component) output etc. etc.

Then, when ECU when igniter 251 transmits electric sparks and produces signals, startups such as switch element in the igniter 251, carry electric current to primary coil 21, meanwhile in secondary coil 22, produce the induced electromotive force (counter electromotive force) that causes by electromagnetic induction, just can from spark plug, produce electric spark.

As Fig. 4, shown in Figure 5, produce vortex flow in order to suppress the forming of magnetic flux that produces by the electric current that flows through in the primary coil 21, the central core 3 of present embodiment is by constituting at radially stacked polylith steel plate 31.

In addition, the resin thin film layer 45 in the insulation sheet material 4 of present embodiment is made of polyethylene terephthalate (PET), and the adhesive linkage 46 in the insulation sheet material 4 is made of the bonding agent (sticker) of propylene system.

And the insulating resin of present embodiment 5 is made of epoxy resin.

As Fig. 2, shown in Figure 4, the winding end 42 in the insulation sheet material 4 of present embodiment with respect to the insulation sheet material 4 Width W inclination pre-determined tilt angle θ and form.The terminal 42 axial L with respect to above-mentioned central core 3 of this winding have 5 °～60 ° tilt angle theta.

And as shown in Figure 6, the insulation sheet material 4 of present embodiment cuts off the long size insulation sheet material 40 that is wound in the cylinder shape repeatedly with predetermined length, mass-produces the product of same shape.

And as shown in Figure 2, four bights of insulation in the sheet material 4 are not the right angle, but the both ends 40 among winding direction (length direction) D of insulation sheet material 4, promptly to twine starting end 41 are identical angles with the tilt angle theta of twining end 42.

And the length of the insulation sheet material 4 of present embodiment at both ends 43 on the Width W is identical and length and the tilt angle theta both ends 40 in winding direction (length direction) D are also identical, is the shape of parallelogram.

And as shown in Figure 2, the winding starting end 41 of insulation sheet material 4 and winding terminal 42 have acute angle-shaped sheet material bight 411,421 and shape sheet material bight, obtuse angle 412,422 respectively.And insulation sheet material 4 begins to twine to central core 3 from the acute angle-shaped sheet material bight 411 of twining starting end 41, is wound into the acute angle-shaped sheet material bight 421 of twining end 42 and finishes.As shown in Figure 3, twine terminal 42 acute angle-shaped sheet material bight 421 carry out welding, crimping or rivet hot etc. and form the usefulness that prevents to come off fix 49.

And the resin thin film layer 45 in the insulation sheet material 4 preferably uses coefficient of linear expansion smaller or equal to 25 * 10 ^-6/ ℃ material.And the winding thickness t that is wrapped in the resin thin film layer 45 on the outer peripheral face 301 of central core 3 is more preferably greater than equaling at 0.1mm.

And at each winding position of the axial L of central core 3, insulation sheet material 4 preferably twines more than 2 layers.

In addition, when the raw thickness of the resin thin film layer 45 before insulation sheet material 4 uses on the outer peripheral face 301 that for example is wrapped in central core 3 was the material of 25 μ m, insulation sheet material 4 can twine more than 4 layers at each winding position of the outer peripheral face 301 of central core 3.Certainly, because twine the number of plies when increasing its assembleability with regard to variation, so the writhing number of insulation sheet material 4 is preferably in below 10 layers.

And as shown in Figure 1, an axial end 32 of the central core 3 of present embodiment inserts and is configured in the upright iron core maintenance recess of establishing in the retaining member 252 that is formed at above-mentioned igniter 251 253.Therefore, the insulation sheet material 4 of present embodiment does not twine near an axial end 32 of the outer peripheral face 301 of central core 3.And, in iron core keeps recess 253, also insert the elastomeric element 321 that disposes on the axial end 32 that is provided in central core 3.

And, insulation sheet material 4 is under elastomeric element 321 or the state on the axial end 32 of permanent magnet configuration in central core 3 with cylindrical shape, the outer peripheral face 301 of central core 3 not only can be wrapped in, and the outer peripheral face of elastomeric element 321 can be wrapped in.The insulation sheet material 4 of present embodiment is wrapped on the outer peripheral face 301 of central core 3, and is wrapped on the elastomeric element 321 on another axial end 32 that is equipped on central core 3.

The following describes the manufacture method of ignition coil 1.

In the present embodiment, following sheet material forms operation, winding working procedure, fixedly operation, assembling procedure and resin filling work procedure come manufacturing place fire coil 1 by carrying out.

At first, as shown in Figure 6, in sheet material forms operation, be 0.8～1.2 times of axial length x of central core 3 with sheet width w according to predetermined length, the long size insulation sheet material 40 that is wound in the cylinder shape cuts off and form the sheet material 4 that insulate.And the resin thin film layer 45 that the front end band twines part is connected with the adhesive linkage 46 that the rear end band twines part temporarily, is the cylinder shape and twines insulation sheet material 40.

At this moment, use the cutting machine 6 that tilts with the Width W of winding direction D quadrature to cut off insulation sheet materials 40.So the cut-out end 40 of the both sides of the insulation sheet material 4 that cut off to form tilts 5 °～60 ° and form with respect to the Width W of insulation sheet material 40.

Like this, just formed sheet width w be 0.8～1.2 times of axial length x of central core 3 and with the winding direction D of Width W quadrature on the insulation sheet material 4 that tilts of both ends 40.

Then, as shown in Figure 2, in winding working procedure, make the Width W of insulation sheet material 4 consistent, the outer peripheral face 301 of insulation sheet material 4 to central core 3 twined with the axial L of central core 3.At this moment, insulation sheet material 4 is wrapped on the Zhou Fangxiang R of this central core 3 under its Width W state parallel with the axial L of central core 3 abreast.

Then, the adhesive linkage 46 of insulation sheet material 4 is relative with the outer peripheral face 301 of central core 3, a side of above-mentioned skewed cut-out end 40 as twining starting end 41, is twined acute angle-shaped sheet material bight 411 starting end 41 to central core 3 windings from this.

So the acute angle-shaped sheet material bight 411 of twining in the starting end 41 is covered by the part of the insulation sheet material 4 that twines from the back.And the adhesive linkage 46 that the rear end band twines part is connected with the resin thin film layer 45 that the front end band twines part, twines insulation sheet material 4.

Like this, as shown in Figure 3, insulation sheet material 4 as twining end 42, is wrapped in above-mentioned skewed cut-out end 40 on the acute angle-shaped sheet material bight 421 in this winding terminal 42.

Next, as shown in Figure 3, in fixing operation, on the acute angle-shaped sheet material bight 421 that is formed on the above-mentioned winding end 42, carry out operations such as welding, crimping or rivet hot, the usefulness that prevents to come off fix 49.Thus, needn't fix 49, need only fix 49 in acute angle-shaped sheet material bight 421 insulating trip material 4 is not come off in whole winding terminal 42.

In addition,, can think that this shape sheet material bight, obtuse angle 422 is difficult to come off though shape sheet material bight, obtuse angle 422 is also arranged at the winding end 42 of insulation sheet material 4, thus needn't above-mentioned slip-off preventing use fix 49.

Next, in assembling procedure, assembling primary coil 21, secondary coil 22, central core 3, periphery iron core 24, igniter 251 etc. in above-mentioned solenoid housing 20.

Afterwards, in the resin filling work procedure, fill epoxy resin in slit 29 in cylindrical portion 2 and the igniter configuration recess 25, make each parts be made into integration ignition coil 1 as insulating resin 5.

In addition, in this resin filling work procedure, between insulation sheet material 4 on the outer peripheral face 301 that is wound in central core 3 and secondary bobbin 221, fill insulating resin 5 at the secondary coil 22 of its outer circumferential side.

In the ignition coil 1 of present embodiment, the winding end 42 of the insulation sheet material 4 on the outer peripheral face 301 of winding subcenter iron core 3, its whole axial L of central core 3 relatively is formed slopely.

Therefore, in being wound in the insulation sheet material 4 of central core 3,, also can reduce this power that this insulation sheet material 4 is come off even the restoring force of the strain that produces on being wound into central core 3 time act as the power that this insulation sheet material 4 is come off.

In addition, the power that insulation sheet material 4 is come off concentrates on the acute angle-shaped sheet material bight 421 of twining in terminal 42.Therefore, fix 49, can make for a long time and twine terminal 42 integral body and do not come off by what on the acute angle-shaped sheet material bight 421 of twining in terminal 42, carry out the above-mentioned usefulness that prevents to come off.

And said fixing 49 needn't be carried out on the winding end 42 of whole insulation sheet material 4, can keep insulation sheet material 4 simply and be wrapped in state on the central core 3.

And, for having the effect that is difficult to come off that the above-mentioned skewed insulation sheet material 4 (with reference to Fig. 4) that twines the present embodiment of end 42 is compared with the insulation sheet material 94 (with reference to Figure 18) in the past with winding end 942 parallel with the axial L of central core 3, can carry out following explanation.

That is, as shown in Figure 5, in order to suppress the generation of vortex flow, central core 3 has used the iron core of several steel plates 31 radially stacked.Therefore, at the outer peripheral face 301 of central core 3 along step space 311 that the axial L shaped one-tenth of whole central core 3 forms between steel plate 31.

So, will be, be consistent with formation direction in most cases towards the winding end 42 of the insulation sheet material 94 of the axial L of central core 3 towards the formation direction in the step space 311 of the axial L of central core 3 as Figure 17, when the insulation sheet material 94 in the past with winding end 942 parallel with the axial L of central core 3 shown in Figure 180 is wound on the central core 3.At this moment, because the formation direction in step space 311 is consistent with the formation direction of twining terminal 42, twines terminal 42 and be easy to by step space 311 in radial displacement, insulation sheet material 4 comes off easily.

Relative therewith, will can twine terminal 42 with respect to step space 311 sloped position as Fig. 2, when the skewed insulation sheet material 4 that twines end 42 with present embodiment shown in Figure 4 is wound on the central core 3.Therefore, according to the insulation sheet material 4 of present embodiment, the winding end of sheet material 4 is difficult to come off even central core 3 at radially stacked polylith steel plate 31, also can guarantee to insulate.

And, as shown in Figure 5, the insulating resin 5 of filling between the secondary bobbin 221 of the insulation sheet material 4 of the outer peripheral face 301 that is wound in central core 3 and secondary coil 22 is cylindric, and the position of side forms resin stage portion 51 in the winding end 42 with insulation sheet material 4 is connected interior Monday.

When being wound into above-mentioned insulation sheet material 94 in the past on the central core 3, this resin stage portion 51 forms with the axial L of above-mentioned cylindric insulating resin 5 abreast by the winding parallel with the axial L of above-mentioned central core 3 terminal 942.(with reference to Figure 18)

So, in the ignition coil that uses insulation sheet material 94 in the past, when engine heating back cooling ignition coil, above-mentioned cylindric insulating resin 5 is because of thermal stress and to radially shrinking, at this moment, can produce stress on the resin stage portion 51 parallel with above-mentioned axial L concentrates.That is, such stress is concentrated the place of the circumferencial direction R that occurs in central core 3.Therefore, in ignition coil in the past, the insulating resin 5 of drum might produce cracking on resin stage portion 51.

Relative therewith, when the insulation sheet material 4 with present embodiment was wound on the central core 3, by the winding end 42 that the axial L with above-mentioned central core 3 tilts, above-mentioned resin stage portion 51 was formed obliquely (with reference to Fig. 4) with the axial L of central core 3.

Therefore, in the ignition coil 1 of the insulation sheet material 4 that has used present embodiment, when engine heating back cooling ignition coil 1, above-mentioned cylindric insulating resin 5 is because of thermal stress and to radially shrinking, at this moment, concentrating at the stress that produces on the resin stage portion 51 is not 1 position that concentrates on the Zhou Fangxiang R of central core 3, but is scattered on the Zhou Fangxiang R of central core 3.Therefore,, act on resin stage portion 5, also can make cylindric insulating resin 5 be difficult to produce cracking even stress is concentrated if adopt the ignition coil 1 of embodiment.

And, as mentioned above, because the sheet width w of insulation sheet material 4 is 0.8～1.2 times of axial length x of central core 3.Therefore, as long as make the Width W of insulation sheet material 4 consistent with the axial L of central core 3, insulation sheet material 4 to the Zhou Fangxiang of central core 3 R wound in parallel, just can be covered the outer peripheral face 301 of whole central core 3, thus the increase of the sheet material 4 winding number of times that can suppress to insulate.

Therefore,, not only can make insulating trip material 4 be difficult to come off, be wrapped in state on the central core 3 but also can keep insulation sheet material 4 simply if adopt the ignition coil 1 of present embodiment, and the increase of the winding number of times of the sheet material 4 that can suppress to insulate.

(embodiment 2)

Present embodiment such as Fig. 7, shown in Figure 8 are the embodiment that insulation sheet material 4 that the paddy shape tilts is wrapped in the ignition coil 1 on the central core 3 for having with above-mentioned winding end 42.

The incline direction that the paddy shape of present embodiment twines end 42 reverses halfway.

And, the insulation sheet material 4 of present embodiment identical with shown in the foregoing description 1, be cut the insulation sheet material 40 of long size repeatedly and produce in batches, twine starting end 41 and have the mountain shape winding starting end 41 that twines terminal 42 shape along the paddy shape with cutting machine 6.

The paddy shape winding terminal 42 of present embodiment is 5 °～60 ° with respect to the tilt angle theta of the axial L of central core 3.

In addition, the winding end 42 of present embodiment has a paddy shape, has acute angle-shaped sheet material bight 421 respectively at the both ends of the axial L of central core 3.So what the insulation sheet material 4 of present embodiment carried out on two acute angle-shaped sheet material bights 421 that above-mentioned slip-off preventing uses fixes 49, in case anti-avulsion falls.

In addition, shown in Figure 10 as Fig. 9, insulation sheet material 4 can mountain, obtuse angle shape crustal inclination form winding end 42, and obtuse angle paddy shape crustal inclination forms twines starting end 41.At this moment, must be since two acute angle-shaped sheet material bights 421 twine insulation sheet materials 4, this to begin to twine be difficulty, has only shape sheet material bight, obtuse angle 422 to be positioned in addition to twine terminal 42, can omit said fixing 49.

In the present embodiment, other is identical with the foregoing description 1, can obtain the action effect identical with the foregoing description 1.

(embodiment 3)

Present embodiment such as Figure 11～shown in Figure 13, in the insulation sheet material 4 on being wound in central core 3, the embodiment of the ignition coil 1 that will be folded to form to the axial end 32 of central core 3 from the outstanding axial remainder of the axial end 32 of central core 3 (outstanding end) 44.

In the present embodiment, use as folding anchor clamps 7 that the axial remainder 44 of Figure 11, the sheet material 4 that will insulate shown in Figure 12 folds in the axial end 32 of central core 3.This folding anchor clamps 7 possess the internal diameter circular depressions 71 bigger slightly than the external diameter of the axial end 32 of central core 3.This circular depressions 71 has bottom surface 711 and is used for the axial remainder 44 of folding insulation sheet material 4 and 711 periphery tilts from the bottom surface tilt internal wall face 712.

In the present embodiment, as shown in figure 11, when the sheet material 4 that will insulate was wound on the central core 3, the part of insulation sheet material 4 was outstanding from the axial end 32 of central core 3, forms axial remainder 44.At this moment, it is outstanding from the axial end 32 of central core 3 to be positioned at the part in acute angle-shaped sheet material bight 421 of winding end 42 of insulation sheet material 4.

So, in the present embodiment, twine the come off above-mentioned folded clip tool 7 of 49 usefulness of fixing of usefulness of preventing on the acute angle-shaped sheet material bight 421 in terminal 42 acute angle-shaped sheet material bight 421 folded and carries out to the axial end 32 of central core 3.

That is, as shown in figure 11, after the sheet material 4 that will insulate is wound on the above-mentioned central core 3, make above-mentioned folding anchor clamps 7 near the axial end 32 outstanding axial remainders 44 that form from central core 3.At this moment, as shown in figure 12, axially remainder 44 connects with the tilt internal wall face 712 of the circular depressions 71 that is positioned at folding anchor clamps 7, and is folding crooked to center one side thus.Then, as shown in figure 13, axially remainder 44 connects with the bottom surface 711 of circular depressions 71, is fixed on the axial end 32 of central core 3.

So, the axial remainder 44 of insulation sheet material 4 is folding to the axial end 32 of central core 3, the winding end 42 of the sheet material 4 that can insulate fix 49.

Present embodiment also can make the winding end 42 of insulation sheet material 4 not come off.

In addition, it is the littlest to can be compared to the radius of central core 3 most from the length x1 of the axial remainder 44 of the outstanding insulation sheet material 4 of the axial end 32 of above-mentioned central core 3.At this moment, being folded to needn't be too much overlapping fixing between the axial remainder 44 of axial end 32 of central core 3, can adjust the shape to the folding axial remainder 44 of the axial end 32 of central core 3.

And, when above-mentioned folding anchor clamps 7 are fixed on above-mentioned axial remainder 44 on the axial end 32 of central core 3,, the winding end 42 of insulation sheet material 4 is not come off by this axial remainder 44 is carried out ultrasonic wave coating etc.

The other parts of present embodiment are identical with the foregoing description 1,2, can obtain the action effect identical with the foregoing description 1,2.

(embodiment 4)

Present embodiment sets the example that permanent magnet 33 forms respectively for axial both ends at central core 3A as shown in figure 14.

So the sheet width w of the insulation sheet material 4 of present embodiment is 0.8～1.2 times of axial length x of above-mentioned central core 3A that comprises the axial length of pair of permanent magnets 33.

In the present embodiment, can make the winding end 42 of insulating trip material 4 be difficult to come off from the central core 3A that sets permanent magnet 33 respectively at axial both ends.

The other parts of present embodiment are identical with the foregoing description 1～3, can obtain the action effect same with the foregoing description 1～3.

And, as shown in figure 15, in the foregoing description 1～4, the sloping portion of the winding end 42 of insulation sheet material 4 need not to form on the length of whole winding terminal 42, for example, can in the zone more than 50% of the Width W of this sheet material 4 that insulate (in figure, the zone that w/2 is above), form.In such cases, can make insulating trip material 4 be difficult to come off from central core 3.

And, as shown in figure 16, in the foregoing description 1～4, the winding starting end 41 of above-mentioned insulation sheet material 4 is at right angles formed with respect to the axial L (the Width W of insulation sheet material 4) of central core 3, and the terminal 42 axial L with respect to central core 3 of winding (the Width W of insulation sheet material 4) are formed obliquely.

In addition, in the foregoing description 1～4, the sloping portion that is positioned at the winding end 42 of insulation sheet material 4 is not necessarily wanted linearly inclination, also can tilt by curved shape.At this moment, be positioned at twine terminal 42 sloping portion needn't whole curved shape, also can make the curved shape of a part of the sloping portion of its linearity.

And the sloping portion that twines starting end 41 also can be formed slopely by same curved shape.

Claims (18)

1. ignition coil, have: bar-shaped central core and be wound on primary coil around this central core and the cylindrical portion of secondary coil with possessing concentric circles, on the outer peripheral face of above-mentioned central core, twine the insulation sheet material, and between this insulation sheet material and above-mentioned cylindrical portion, fill insulating resin, it is characterized in that

Above-mentioned insulation sheet material comprises the resin thin film layer that is formed by synthetic resin and is provided in the adhesive linkage at this resin thin film layer back side, sheet width is 0.8 times～1.2 times of axial length of above-mentioned central core, and it twines the terminal sloping portion that has with respect to the axioversion of above-mentioned central core.

2. ignition coil, have: bar-shaped central core and be wound on primary coil around this central core and the cylindrical portion of secondary coil with possessing concentric circles, on the outer peripheral face of above-mentioned central core, twine the insulation sheet material, and between this insulation sheet material and above-mentioned cylindrical portion, fill insulating resin, it is characterized in that

Above-mentioned insulation sheet material comprises the resin thin film layer that is formed by synthetic resin and is provided in the adhesive linkage at this resin thin film layer back side, under the state before being wound on the above-mentioned central core, sheet width is 0.8 times～1.2 times of axial length of above-mentioned central core, and a pair of axial end portion that is positioned at Width is parallel to each other, twines the terminal sloping portion that has with respect to above-mentioned Width inclination in the time of on being wound into above-mentioned central core.

3. ignition coil as claimed in claim 2 is characterized in that above-mentioned insulation sheet material makes the axially parallel of its Width and above-mentioned central core, and is wrapped on this central core.

4. as each described ignition coil in the claim 1～2, it is characterized in that above-mentioned central core forms by radially stacked polylith steel plate.

5. as each described ignition coil in the claim 1～2, it is characterized in that above-mentioned winding end has acute angle-shaped sheet material bight, forming be used to prevent to come off fixing in this acute angle-shaped sheet material bight.

6. as each described ignition coil in the claim 1～2, it is characterized in that the sloping portion that is positioned at above-mentioned winding end has axial 5 °～60 ° angle of inclination with respect to above-mentioned central core.

7. as each described ignition coil in the claim 1～2, it is characterized in that the sloping portion integral body of above-mentioned winding end tilts to same direction.

8. as each described ignition coil in the claim 1～2, it is characterized in that the incline direction of the sloping portion of above-mentioned winding end reverses halfway, be mountain shape or paddy shape.

9. as each described ignition coil in the claim 1～2, it is characterized in that above-mentioned insulation sheet material is folding to the axial end of above-mentioned central core with axial remainder under the state that twines.

10. as each described ignition coil in the claim 1～2, it is characterized in that, the axial both ends of above-mentioned central core form by setting magnet respectively, and the sheet width of above-mentioned insulation sheet material is 0.8～1.2 times of axial length of above-mentioned central core that has comprised the axial length of above-mentioned pair of magnet.

11. the manufacture method of an ignition coil, this ignition coil has: bar-shaped central core and be wound on primary coil around this central core and the cylindrical portion of secondary coil with possessing concentric circles, on the outer peripheral face of above-mentioned central core, twine and bonding insulation sheet material, and between this insulation sheet material and above-mentioned cylindrical portion, fill insulating resin, the manufacture method of this ignition coil is characterised in that and comprises:

The sheet material that forms the insulation sheet material forms operation, the sheet width of this insulation sheet material is 0.8～1.2 times of axial length of above-mentioned central core, and with at least one end of the winding direction of Width quadrature on the sloping portion that tilts with respect to above-mentioned Width is set;

Winding working procedure, the Width that makes above-mentioned insulation sheet material is axial consistent with above-mentioned central core, and this insulation sheet material is wrapped in the outer peripheral face of above-mentioned central core, and it is terminal to make the end that is provided with above-mentioned sloping portion be positioned at this winding.

12. the manufacture method of ignition coil as claimed in claim 11 is characterized in that, above-mentioned central core forms by radially stacked polylith steel plate.

13. the manufacture method as claim 11 or 12 described ignition coils is characterized in that, after having carried out above-mentioned winding working procedure, carries out being used in the terminal acute angle-shaped sheet material bight that forms of above-mentioned winding preventing the fixing fixedly operation that comes off.

14. manufacture method as claim 11 or 12 described ignition coils, it is characterized in that, form in the operation at above-mentioned sheet material, the sloping portion of an end of above-mentioned winding direction that makes above-mentioned insulation sheet material is with respect to tilt 5 °～60 ° angle of inclination of the Width of above-mentioned insulation sheet material.

15. the manufacture method as claim 11 or 12 described ignition coils is characterized in that, forms in the operation at above-mentioned sheet material, and the sloping portion integral body of an end of the above-mentioned winding direction of above-mentioned insulation sheet material is tilted to same direction.

16. manufacture method as claim 11 or 12 described ignition coils, it is characterized in that, form in the operation at above-mentioned sheet material, the incline direction of sloping portion of an end of the above-mentioned winding direction of above-mentioned insulation sheet material is reversed halfway, form mountain shape or paddy shape.

17. manufacture method as claim 11 or 12 described ignition coils, it is characterized in that, in above-mentioned winding working procedure, above-mentioned insulation sheet material is twined highlightedly from the axial end of above-mentioned central core, and the axial remainder that will be in this winding state is folding to the axial end of above-mentioned central core.

18. manufacture method as claim 11 or 12 described ignition coils, it is characterized in that, the axial both ends of above-mentioned central core form by setting magnet respectively, and the sheet width of above-mentioned insulation sheet material is 0.8～1.2 times of axial length of above-mentioned central core that has comprised the axial length of above-mentioned pair of magnet.

Images