JP2002015921A - Mounting structure and method of pot-type ferrite core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a pot-type ferrite core to be bonded on a support plate to a uniform level. SOLUTION: A plurality of holes (21) which are to be filled up with thermosetting adhesive agent (20) are bored in a support plate (17), on which a pot-type ferrite core (16) is mounted, and the pot-type ferrite core (16) is fixed on the support plate (17) with the thermosetting adhesive agent (20) thermally cured inside the through-holes (21). Since adhesive agent is not interposed between the pot-type ferrite core and the support plate, the ferrite core can be fixed to a uniform height.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure and a mounting method for mounting a pot type ferrite core to a desired support plate such as a case, a housing, a rotor and the like.

[0002]

2. Description of the Related Art Conventionally, a transformer comprising a pot type ferrite core and a coil has been used as a transformer in which the number of windings on the primary side and the secondary side can be freely combined. FIG. 4 shows a transformer having such a configuration.

As shown in FIG. 4, a bobbin 3 in which a primary side and a secondary side winding are integrally formed is accommodated in the hollow portion of a pair of pot type ferrite cores 1 and 2. A formal wire is wound around the winding portion of the bobbin 3 a predetermined number of times to form a coil 7 (see FIG. 7 or FIG. 8).

The pot type ferrite cores 1 and 2 containing the coil 7 are superimposed as shown in FIG. 5 and then adhered at two points with an epoxy adhesive 4, so that the appearance of the coil 7 is cylindrical and the coil 7 is not exposed. Used as By using in this way, the leakage magnetic flux can be reduced, and it can be applied to various uses.

However, the pot type ferrite cores 1 and 2 are manufactured by solidifying ferrite powder and a binder in a mold by pressure and heat treatment. For this reason, the product is very brittle, and when the powder is not completely filled and the inside becomes uneven, porosity, cracks, and cracks are likely to occur. Therefore, as post-processing, surface polishing can be performed, but processing such as threading and fitting of the core itself is impossible.

Therefore, when attaching the pot type ferrite cores 1 and 2 containing the coil 7 as described above to a housing or the like, holding metal fittings 5 and 6 as shown in FIG. 4 are used. The holding metal fittings 5 and 6 are formed of a non-magnetic material such as, for example, nickel silver or the like. The upper holding metal fitting 5 has a side opening 5 a, and the lower holding metal fitting 6 has a side of the holding metal fitting 5. A protrusion 6a corresponding to the side opening 5a is formed. These holding metal members 5, 6 have resiliency to each other, and as shown in FIG. 6, these holding metal members 5, 6 are fitted from above and below the pot type ferrite cores 1, 2 to form a pot type ferrite core. 1, 2 can be held.

[0007] Then, by inserting the bottom projection 6b formed on the lower holding member 6 into a concave portion of the housing or the like, the transformer composed of the pot type ferrite cores 1 and 2 and the coil is attached to the housing or the like 8. be able to.

The pot-type ferrite cores 1 and 2 may be attached to the housing 8 by embedding the pot-type ferrite cores 1 and 2 in the housing 8 using a molding material or by removing the pot-type ferrite cores 1 and 2 from the housing 8. In some cases, the lead wire of the coil 7 is connected to the housing 8 or the like.

Further, the holding metal fittings 5 and 6 are bonded to the housing or the like 8 with an adhesive, or the pot type ferrite core 1 or 2 is bonded to the housing with a thermosetting adhesive 9 as shown in FIG. And so on.

[0010]

When the holding metal fittings 5, 6 shown in FIGS. 4 to 6 are used, the transformer is fixed to the case, the housing or the like 8 only by the bottom projection 6, so that the mounting is uncertain. Yes, it is difficult to mount on moving or rotating bodies. The same applies when using a molding material or using a lead wire.

Further, as long as the holding metal fittings 5 and 6 are used,
Two pot type ferrite cores 1 and 2 are completely connected,
Since the pot-type ferrite cores 1 and 2 need to be used in close contact with each other, the pot-type ferrite cores 1 and 2 are separated and kept at a constant interval to transmit power and signals without contact. However, when the other pot-type ferrite core 2 or 1 is rotated, it cannot be handled.

As shown in FIG. 7, when the thermosetting adhesive 9 is applied over the entire flat surface of the pot-type ferrite core 1 and adhered to the housing or the like, the pot-type ferrite core, the housing material and the adhesive are used. There are problems such as differences in thermal conductivity, the volume of the pot-shaped core and the housing, and the contact area, and there is a possibility that cracks and cracks may occur in the pot-shaped core 1 by heating and cooling in the bonding step. Also,
ON / OFF of energization to coil 7 even after bonding
, Heating and cooling are repeated, and cracks and cracks may occur in the pot-type ferrite core 1. As shown in FIG. 8, when the adhesive 9 is applied in a dot-like manner, there is no possibility that cracks or the like will occur, but sufficient adhesive strength cannot be obtained. When the pot-type ferrite core 1 is separated and power and signals are transmitted in a non-contact manner, or when one pot-type ferrite core 1 is stopped and the other pot-type ferrite core 2 is rotated,
It is necessary to fix the pot-type ferrite cores 1 and 2 at a fixed distance from each other, and in particular, to fix one pot-type ferrite core 1 or 2 to the other pot-type ferrite core 2 or 1
, It is necessary to keep the height of the pot type ferrite cores 1 and 2 constant in the circumferential direction.
Causes unevenness in the heights of the pot-type ferrite cores 1 and 2. If the height of the pot-type ferrite cores 1 and 2 varies, the transmission of power and signals will be hindered. Therefore, when fixing the pot-type ferrite core using the adhesive 9, the pot-type ferrite core must be re-adhered after bonding. It must be polished.

An object of the present invention is to provide means for solving the above problems.

[0014]

According to a first aspect of the present invention, a thermosetting adhesive (20) is provided on a support plate (17) to which a pot-type ferrite core (16) is attached. A plurality of holes (21) to be filled are formed, and a pot in which the pot-type ferrite core (16) is fixed to the support plate (17) by an adhesive (20) thermoset in each hole (21). Adopts a ferrite core mounting structure.

According to the first aspect of the present invention, the pot type ferrite core (16) is bonded to the support plate (17) in a point-like manner at a plurality of locations, and the pot type ferrite core (16) and the support plate (17) are bonded. Since the adhesive layer does not intervene at the contact portion with the pot type ferrite core (16) without being affected by the thickness of the adhesive layer, coating unevenness, or the like.
Is fixed to the support plate (17) at a uniform height. When the pair of pot-type ferrite cores (16) are opposed to each other, the gap (δ) between the pot-type ferrite cores (16) can be kept small and constant, and the electromagnetic induction characteristics can be enhanced to efficiently use signals or power. Can be transmitted. Adhesive (2
Since the holes (21) for filling 0) can be provided in a desired number and arrangement, the pot type ferrite core (16) can be firmly fixed to the support plate (17). Also,
At the contact portion between the pot-type ferrite core (16) and the support plate (17), there is an adhesive portion and a non-adhesion portion. An escape will be provided and the adhesive (2
The expansion and shrinkage accompanying the heating and cooling of 0) can be absorbed to prevent breakage of the pot-type ferrite core (16), generation of cracks, and the like.

In the invention according to claim 2, the peripheral portion of the pot type ferrite core (16) is made of a rubber-based adhesive (2).
2. The method according to claim 1, wherein said support plate is bonded to said support plate by means of 2).
The mounting structure of the pot type ferrite core described in (1) is adopted.

According to the second aspect of the present invention, the pot type ferrite core (16) can be firmly fixed by the support plate (17) by reinforcing the adhesive strength of the thermosetting adhesive (20).

Further, in the invention according to claim 3, the joint surface (18) of the pot type ferrite core (16) and the joined surface (19) of the support plate (17) are smooth surfaces. Alternatively, the pot type ferrite core mounting structure according to claim 2 is employed.

According to the third aspect of the present invention, the pot type ferrite core (16) can be fixed to the support plate (17) with a more accurate uniform height. Further, it is possible to prevent the adhesive (20) from entering the contact portion between the pot type ferrite core (16) and the support plate (17).

The invention according to claim 4 is characterized in that the hole (21)
A pot type ferrite core (16) is brought into contact with a support plate (17) in which a plurality of holes are formed, and then the hole (21) is filled with a thermosetting adhesive, and then the thermosetting adhesive (2) is filled.
The method of mounting a pot-type ferrite core for performing heating and cooling in 0) is adopted.

According to the fourth aspect of the present invention, it is possible to prevent the adhesive (20) from adhering to the contact portion between the pot type ferrite core (16) and the support plate (17). Therefore, the pot type ferrite core (16) can be fixed to the support plate (17) at a uniform height. In addition, a non-adhesion portion is appropriately secured at a contact portion between the pot-type ferrite core (16) and the support plate (17), and the pot-type ferrite core (16) and the support plate are heated and cooled with the adhesive (20). The expansion and contraction of (17) can be absorbed to prevent breakage of the pot-type ferrite core (16) and the occurrence of cracks.

Further, according to a fifth aspect of the present invention, the peripheral portion of the pot-type ferrite core (16) is provided with a rubber-based adhesive (2).
The method of attaching a pot-type ferrite core according to claim 4, which includes a step of adhering to the support plate (17) by (2).

According to the fifth aspect of the present invention, the adhesive strength of the thermosetting adhesive (20) is reinforced, and the pot type ferrite core (16) can be firmly fixed by the support plate (17).

The invention according to claim 6 is a step of polishing the bonding surface (18) of the pot type ferrite core (16) and the bonding surface (19) of the support plate (17) before bonding. The method of attaching a pot-type ferrite core according to claim 4 or claim 5 is adopted.

According to the sixth aspect of the present invention, the pot type ferrite core (16) can be fixed to the support plate (17) with a more accurate uniform height. Further, it is possible to prevent the adhesive (20) from entering the contact portion between the pot type ferrite core (16) and the support plate (17).

[0026]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In this embodiment, a pair of pot type ferrite core units having a similar structure are prepared, and FIG.
As shown in FIG. 1, one pot-type ferrite core unit 10 is fixed to a stationary part 12 such as a housing or a frame, and the other pot-type ferrite core unit 11 is fixed to a rotating part 13 such as a rotor or a roller. ing. Both pot type ferrite core units 10, 1
Reference numeral 1 denotes a stationary unit 12 and a rotating unit 13 such that their central axes A are in a straight line, and this straight line coincides with the rotating axis of the rotating unit.
Are fixed respectively.

As shown in FIGS. 1 and 2, each of the pot type ferrite core units 10 and 11 includes a coil 15 made of a formal wire wound around a bobbin 14, a pot type ferrite core 16, and a metal support plate. 17 is provided.

The pot type ferrite core 16 is formed by hardening ferrite powder and a binder by applying pressure and heat in a mold, and forms a cylindrical wall 16a, an end wall 16b closing one end of the cylindrical wall 16a, and an end wall 16b. A hollow shaft 16c protruding from the wall 16b and extending on the central axis A of the cylindrical wall 16a. An empty space is formed between the hollow shaft 16c of the pot type ferrite core 16 and the cylindrical wall 16a, and the bobbin 14 around which the coil 15 is wound is housed in the empty room.

The bobbin 14 is a flanged hollow cylindrical member made of polyacetal or the like.
The formal wire is wound a predetermined number of times. Bobbin 14
Is attached to the pot type ferrite core 16 using a synthetic rubber adhesive. For example, the adhesive is applied to one point of the bottom surface of the empty room of the pot-type ferrite core 16 and the bobbin 14 around which the formal wire is wound is stored, and the bobbin 14 is placed at room temperature.
The bonding is performed for about time. The bobbin 14 can be omitted, and the coil 15 may be formed by directly winding a formal wire around the hollow shaft 16c of the pot type ferrite core 16.

The support plate 17 is fixed to the stationary part 12 such as a housing and a case, and the rotating part 13 such as a roller and a rotor by a fixing tool such as a bolt, a fitting means, an adhesive means and the like. The support plate 17 is preferably made of a non-magnetic material such as aluminum, brass, stainless steel or the like, and is formed in a disk shape. Since the support plate 17 is made of a non-magnetic material, it is difficult to generate heat due to magnetic flux leakage, and does not deteriorate an adhesive described later. The support plate 17 may be formed in other shapes such as a square other than a disk.

At the center of the support plate 17, a support protrusion which can be fitted into the hollow of the hollow shaft 16c of the pot type ferrite core 16 and a mounting protrusion which can be inserted into the stationary portion 12 or the rotating portion 13 are provided. By inserting the support projection into the hollow shaft 16c of the pot-type ferrite core 16 and inserting the mounting projection into the hole of the stationary part 12 or the rotating part 13, the positioning of the pot-type ferrite core 16 with respect to the stationary part 12 or the rotating part 13 is achieved. It can be performed. Further, the stationary part 12 and the rotating part 13 can be constituted by the support plate 17.

Pot type ferrite core unit 10, 1
1 is fixed to the support plate 17 by the following mounting structure.

End wall 16b of pot type ferrite core 16
The outer surface of the support plate 17 is smoothly finished as a joining surface 18, and the surface of the support plate 17 facing the joining surface 18 is smoothly finished as a joined surface 19.
Thus, the end wall 16b of the pot type ferrite core 16 is in close contact with the support plate 17. The support plate 17 is provided with a number of holes 21 filled with a thermosetting adhesive 20, and the pot-type ferrite core 16 is fixed to the support plate 17 by the thermosetting adhesive 20 in each hole 21. I have. Further, the peripheral portion of the pot type ferrite core 16 is bonded to the support plate 17 with a rubber adhesive 22.

Bonding surface 18 of pot type ferrite core 16
Since the joined surface 19 of the support plate 17 and the support plate 17 is a smooth surface,
The pot-type ferrite core 16 is in close contact with the support plate 17 and, consequently, the mounting portion 1 which is a stationary portion or a rotating portion shown in FIG.
2 and 13 are fixed at appropriate positions, so that the gap δ between the pair of pot-type ferrite cores 16 and 16 is kept constant. This smooth finishing is performed as needed, and the above-mentioned clearance δ
May be slightly rough as long as it can be kept constant.

The thermosetting adhesive 20 preferably has good insulation and thermal conductivity and exhibits strong adhesive strength. For example, a thermosetting epoxy adhesive (one-pack type) may be used. Can be used. This adhesive 20 is applied to the support plate 1
7 and fixed to the inner wall surface of the hole 21 and the bonding surface 18 of the pot-type ferrite core 16. Support plate 17
The holes 21 are formed at predetermined pitches on a plurality of concentric circles surrounding the central axis A of the support plate 17 as shown in FIG.
8. For this reason, the pot-type ferrite core 16 is bonded to the support plate 17 in a point-like manner at a plurality of locations, and the adhesive layer does not intervene at the contact portion between the pot-type ferrite core 16 and the support plate 17. The shown gap δ becomes constant. Since the contact portion has an adhesive portion and a non-adhesive portion, the pot-type ferrite core 1
As a result, a relief is provided when the adhesive 6 and the support plate 17 expand, and the expansion and contraction accompanying the heating and cooling of the adhesive 20 can be absorbed to prevent the pot type ferrite core 16 from being damaged.

The rubber adhesive 22 is applied on a circular boundary between the peripheral portion of the pot type ferrite core 16 and the support plate 17. Since the bonding force of the rubber-based adhesive 22 is added to the bonding force of the thermosetting adhesive 20, the pot-type ferrite core 16 is firmly bonded by the support plate 17. This rubber-based adhesive 22 can be omitted if the bonding strength of the thermosetting adhesive 20 is sufficient.

Next, a method of mounting the pot type ferrite core unit having the above configuration will be described.

The bonding surfaces 18 of the pair of pot type ferrite cores 16 and the bonding surfaces 19 of the pair of support plates 17 are polished before bonding to make the surfaces flat. The support plate 17 has many holes 21 in advance.
Are drilled so as to penetrate the plate thickness, and a large number of these holes 21 are opened in each surface 19 to be joined. If the joining surface 18 and the joined surface 19 are already smooth, this polishing step is omitted.

Next, the smooth joining surface 18 of each pot type ferrite core 16 is brought into contact with the smooth joining surface 19 having a large number of holes 21 of each support plate 17, and heat is introduced into the holes 21. The curable adhesive 20 is filled. Thermosetting adhesive 20
Adheres only to the small circular joint surface 18 of the pot-type ferrite core 16 viewed from the hole 21 of the support plate 17. As described above, the pot type ferrite core 16 is bonded to the support plate 17 at a plurality of points in a point-like manner, and the adhesive layer does not intervene at the contact portion between the pot type ferrite core 16 and the support plate 17. The height of the core 16 on the support plate 17 becomes uniform without being affected by the thickness of the adhesive layer, unevenness of application, and the like, and the gap δ between the pair of pot-type ferrite cores 16, 16 shown in FIG. .

Next, the thermosetting adhesive 20 is heated and cured. In the present embodiment, as an example, a thermosetting epoxy adhesive (one-pack type) is used. The thermosetting temperature was lower than the Curie point. At the time of thermosetting, the pot-type ferrite core 16 and the support plate 17 were gradually heated, and after reaching the thermosetting temperature, were gradually cooled over a predetermined time. Specifically, heating was performed at 165 ° C. for 90 minutes, and the temperature was returned to room temperature over about 2 hours. The pot type ferrite core 16 and the support plate 17 are simultaneously heated for the curing treatment of the adhesive. However, since the contact portion between the pot type ferrite core 16 and the support plate 17 has an adhesive portion and a non-adhesive portion, The thermal stress at the time of expansion and contraction of the pot-type ferrite core 16 and the support plate 17 is alleviated, so that damage to the pot-type ferrite core 16 is prevented.

Pot type ferrite core 16 and support plate 1
7, the pot type ferrite core 16 is
Is bonded by a rubber-based adhesive 22.
The pot-type ferrite core 16 is fixed on the support plate 17 by the rubber-based adhesive 22. As a result, the strength against an impact force is improved and the pot-type ferrite core 16 is hardly peeled off.

Thus, the pot type ferrite core 1
One of a pair of support plates 17 to which 6 is adhered is fixed to a stationary portion 12 such as a housing, and the other is fixed to a rotating portion 13 such as a rotor. Thereby, the pair of pot-type ferrite cores 16 and 16 face each other with a small and constant gap δ without intervening other members. Therefore, the pair of pot type ferrite cores 16 and 16 exhibit desired electromagnetic induction characteristics in transmission of a non-contact signal or power in a rotating system.

In the case where the support plate has a structure in which a shaft-shaped support projection and a mounting projection are provided, the center axes of the pair of pot-type ferrite cores are easily matched with the rotation center axes of the rotating system. The pair of pot-type ferrite cores can be rotated without eccentricity.

[0045]

According to the first aspect of the present invention, the pot-type ferrite core is bonded to the support plate in a plurality of points at a plurality of points, and an adhesive layer is provided at a contact portion between the pot-type ferrite core and the support plate. Since there is no interposition, the pot-type ferrite core is fixed to the support plate at a uniform height without being affected by the thickness of the coating layer of the adhesive or the coating unevenness. When a pair of pot-type ferrite cores are opposed to each other, the gap between the pot-type ferrite cores can be kept small and constant, so that the electromagnetic induction characteristics can be enhanced and signals or power can be transmitted efficiently. Since a desired number and arrangement of the holes for filling the adhesive can be provided, the pot type ferrite core can be firmly fixed to the support plate. In addition, since there is an adhesive portion and a non-adhesive portion in the contact portion between the pot type ferrite core and the support plate, a relief is provided when the pot type ferrite core and the support plate expand each other. The expansion and shrinkage caused by heating and cooling can be absorbed to prevent breakage of the pot type ferrite core and generation of cracks.

According to the second aspect of the present invention, the pot-type ferrite core can be firmly fixed to the support plate by reinforcing the adhesive strength of the thermosetting adhesive.

According to the third aspect of the present invention, the pot type ferrite core can be fixed to the support plate at a more uniform height. Further, it is possible to prevent the adhesive from entering the contact portion between the pot type ferrite core and the support plate.

According to the fourth aspect of the present invention, it is possible to prevent the adhesive from adhering to the contact portion between the pot type ferrite core and the support plate. Therefore, the pot-type ferrite core can be fixed to the support plate at a uniform height. In addition, the non-adhesion part is properly secured at the contact part between the pot type ferrite core and the support plate, and the expansion and contraction of the pot type ferrite core and the support plate due to the heating and cooling of the adhesive are absorbed, and the pot type ferrite core is absorbed. Damage, cracks, and the like can be prevented.

According to the fifth aspect of the present invention, the adhesive strength of the thermosetting adhesive is reinforced, and the pot-type ferrite core can be firmly fixed by the support plate.

According to the sixth aspect of the present invention, the pot type ferrite core can be fixed to the support plate at a more uniform height. Further, it is possible to prevent the adhesive from entering the contact portion between the pot type ferrite core and the support plate.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a pot-type ferrite core unit according to the present invention.

FIG. 2 is a vertical sectional view showing a mounting structure of a pot type ferrite core unit according to the present invention.

FIG. 3 is an elevational view showing a state in which one of a pair of pot-type ferrite core units is attached to a stationary unit and the other is attached to a rotating unit.

FIG. 4 is an exploded perspective view showing a pair of conventional pot type ferrite core units.

FIG. 5 is a perspective view of an assembly of a pair of pot-type ferrite core units shown in FIG.

6 is a vertical sectional view of a pair of pot type ferrite core units shown in FIG.

FIG. 7 is a vertical sectional view showing a state where a conventional pot-type ferrite core unit is attached to a housing or the like.

8 is a vertical sectional view showing a state where a conventional pot type ferrite core unit is attached to a housing or the like by a method different from the method shown in FIG. 7;

[Explanation of symbols]

 Reference Signs List 16: Pot-type ferrite core 17: Support plate 18: Joint surface of pot-type ferrite core 19: Joined surface of support plate 20: Thermosetting adhesive 21: Hole 22: Rubber-based adhesive δ: Gap

Claims (6)

[Claims] 1. A support plate on which a pot-type ferrite core is mounted is provided with a plurality of holes for filling with a thermosetting adhesive, and the pot-type ferrite core is supported by the thermosetting adhesive in each hole. Mounting structure for pot-type ferrite core, which is fixed to a plate. 2. A mounting structure for a pot-type ferrite core according to claim 1, wherein a peripheral portion of said pot-type ferrite core is adhered to said support plate by a rubber-based adhesive. 3. The mounting structure for a pot-type ferrite core according to claim 1, wherein the joining surface of the pot-type ferrite core and the surface to be joined of the support plate are smooth surfaces. 4. A pot type ferrite core is brought into contact with a support plate having a plurality of holes formed therein, and then the holes are filled with a thermosetting adhesive. Thereafter, heating and cooling of the thermosetting adhesive are performed. A method of mounting a pot-type ferrite core, wherein the method is performed. 5. The method for mounting a pot-type ferrite core according to claim 4, further comprising a step of bonding a peripheral portion of the pot-type ferrite core to the support plate with a rubber-based adhesive. 6. The pot-type ferrite core according to claim 4, further comprising a step of polishing the bonding surface of the pot-type ferrite core and the surface to be bonded of the support plate before bonding. Mounting method.