Transformer apparatus with shielding architecture and shielding method thereof

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0001] The present invention relates in general to a transformer apparatus and a shielding method and, more particularly, to a transformer apparatus with shielding architecture and related shielding method.

2. Description of the Prior Art

[0002] Please refer to Fig. 1 and Fig. 2. Fig. 1 is a schematic side view showing the configuration of a conventional transformer apparatus. Fig. 2 is a circuit diagram of the transformer apparatus shown in Fig. 1. The conventional transformer apparatus 100 comprises a toroidal core 105, a primary winding 110, a secondary winding 120, an UL tube 160, an epoxy resin 170, a base 180, and a plurality of lead terminals 111, 112, 121 and 122.

[0003] The primary winding 110 having a predetermined number of turns is wound around the toroidal core 105. The primary winding 110 has two lead terminals 111 and 112 to which an AC power source is applied. The secondary winding 120 having another predetermined number of turns is also wound around the toroidal core 105. The secondary winding 120 has two lead terminals 121 and 122 which are connected to a load. The UL tube 160 enfolding the primary winding 110 and the secondary winding 120 is water resistant and offers protection for the primary winding 110 and the secondary winding 120 against water or moisture. The epoxy resin 170 is utilized for mounting the toroidal core 105 onto the base 180.

[0004] However, the conventional transformer apparatus 100 is not able to offer protection against external electrical noises, and it is well known that there are noise-generating devices everywhere, which function as noise sources to other peripheral electronic devices. The electrical noises from such noise-generating devices may cause a power line disturbance due to a fluctuating magnetic field in the toroidal core 105 affected by the noise-related electromagnetic interference and have a bad effect on other peripheral electronic devices. Therefore, the electronic devices having voltage sensitive feature may be subject to a software malfunction or a hardware breakdown resulting from the external electrical noises.

[0005] GB 1 243 495 A describes a method for electro-static shielding of transformers including: placing an inner winding on a toroidal core; coating the inner winding and toroidal core with an insulation; electroless coating the insulated structure with an electrically conductive material; scribing an air gap in the conductive material; electroplating the scribed structure with copper; insulating the electroplated structure; and forming an outer winding on said insulated and plated structure.

[0006] EP 0 747 913 A1 describes a method for electrically coupling metal windings of an electronic component comprising: providing an electronic component comprised of a plurality of metal windings and having a surface; forming an insulating layer overlying the surface of the electronic component; and forming a metal film overlying the surface of the insulating layer such that a capacitive load of the plurality of metal windings is reduced and operates in a re-entrant mode.

[0007] Accordingly, there is a big need to take measures against electric noises for reliability enhancement and lifetime protection of various electronic devices. That is to say, a noise-shielded transformer apparatus is required to prevent electrical noises generated by a noise-making device from penetrating into other peripheral devices.

[0008] For that reason, the present invention provides a transformer apparatus with shielding architecture and related shielding method to solve the aforementioned problems.

SUMMARY OF THE INVENTION

[0009] It is therefore a primary objective of the present invention to provide a shielded transformer apparatus for solving the prior art problems.

[0010] In accordance with an objective of the present invention, a transformer apparatus having functionalities of shielding external electronic noises and protecting against erosion is provided. The transformer apparatus comprises a toroidal core, a primary winding, a secondary winding, a protection tape, a metal foil, and an UL tube. The primary winding is wound around the toroidal core at one side. The secondary winding is wound around the toroidal core at the other side opposite to the primary winding. The protection tape is wrapped around the primary winding and the secondary winding. The metal foil encloses the protection tape. The UL tube enfolds the metal foil.

[0011] The present invention further provides a transformer shielding method for generating a shielded transformer apparatus. The transformer shielding method comprises: winding a primary winding using an insulated wire around a toroidal core at one side, winding a secondary winding using an insulated wire around the toroidal core at the other side opposite to the primary winding, mounting the toroidal core onto a base by an epoxy resin, wrapping the primary winding and the secondary winding by a protection tape, enclosing the protection tape by a metal foil, and enfolding the metal foil by an UL tube.

[0012] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiments that are illustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The above and other objects and features of the present invention will become apparent from the subsequent description of preferred embodiments given in conjunction with the following accompanying drawings.

Fig. 1

is a schematic side view showing the configuration of a conventional transformer apparatus.

Fig. 2

shows a circuit diagram of the transformer apparatus shown in Fig. 1.

Fig. 3

is a schematic side view showing the configuration of a transformer apparatus in accordance with a first preferred embodiment of the present invention.

Fig. 4

shows a circuit diagram of the transformer apparatus shown in Fig. 3.

Fig. 5

is a schematic side view showing the configuration of a transformer apparatus in accordance with a second preferred embodiment of the present invention.

Fig. 6

shows a circuit diagram of the transformer apparatus shown in Fig. 5.

Fig. 7

illustrates a flowchart depicting a transformer shielding method in accordance with a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0014] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Here, it is to be noted that the present invention is not limited thereto.

[0015] Please refer to Fig. 3 and Fig. 4. Fig. 3 is a schematic side view showing the configuration of a transformer apparatus in accordance with a first preferred embodiment of the present invention. Fig. 4 is a circuit diagram of the transformer apparatus shown in Fig. 3. The transformer apparatus 300 comprises a toroidal core 305, a primary winding 310, a secondary winding 320, a protection tape 363, a metal foil 366, an UL tube 360, an epoxy resin 370, a base 380, and a plurality of lead terminals 311, 312, 321 and 322. The epoxy resin 370 is utilized for mounting the toroidal core 305 onto the base 380.

[0016] The primary winding 310 having a predetermined number of turns is wound around the toroidal core 305 at one side. The primary winding 310 has two lead terminals 311 and 312 to which an AC power source (not shown) is applied. The secondary winding 320 having another predetermined number of turns is wound around the toroidal core 305 at the other side opposite to the primary winding 310. The secondary winding 320 has two lead terminals 321 and 322 which are connected to a load (not shown).

[0017] The wires of the primary winding 310 and the secondary winding 320 can be oleoresinous enameled wires, synthetic enameled wires, polyurethane enameled wires, polyester enameled wires, polyester-imide enameled wires, nylon coated polyurethane enameled wires, or tinnable polyester enameled wires. Alternatively, the wires of the primary winding 310 and the secondary winding 320 can be triple-insulation wires having triple-layer insulation covering which offer extra protection against pinholes and reinforce tolerance for temperature. The functionalities of the toroidal core 305, the primary winding 310, and the secondary winding 320 are well known to those skilled in the art and, for the sake of brevity, further discussion is omitted.

[0018] The protection tape 363 is an insulation tape and is wrapped around the toroidal core 305 together with the primary winding 310 and the secondary winding 320 in the manner shown in Fig. 3 for protecting the primary winding 310 and the secondary winding 320 against erosion. It is noteworthy to point out that the protection tape 363 substantially encloses the primary winding 310 and the secondary winding 320 although the schematic diagram of Fig. 3 is not convenient to clearly demonstrate the protection architecture. The protection tape 363 can be a polyethylene tape. The metal foil 366 is used to enclose the protection tape 363 in the manner shown in Fig. 3 so that external electrical noises such as electromagnetic waves cannot penetrate to affect the operations of the toroidal core 305, the primary winding 310 and the secondary winding 320. The metal foil 366 can be a copper foil, an aluminum foil, or a tin foil. The UL tube 360 enfolding metal foil 366 is water resistant and offers rudimentary protection against water or moisture, which in turn protects the metal foil 366 against oxidation and corrosion. In accordance with another embodiment of the present invention, the bottom edge of the protection tape 363, the metal foil 366, or the UL tube 360 can be glued to the base 380 by another epoxy resin (not shown) so that the toroidal core 305 together with the primary winding 310 and the secondary winding 320 can be sealed closely within the space enclosed by the protection tape 363, the metal foil 366, or the UL tube 360, and the base 380.

[0019] In summary, compared with the conventional transformer apparatus 100 shown in Fig. 1, the transformer apparatus 300 according to the present invention offers two extra protection shields for reinforcing structure of the transformer apparatus and preventing penetration of external electrical noises. Furthermore, the two extra protection shields by the copper foil and the polyethylene tape are actually a cost-effective means for solving the prior art problems.

[0020] Please refer to Fig. 5 and Fig. 6. Fig. 5 is a schematic side view showing the configuration of a transformer apparatus in accordance with a second preferred embodiment of the present invention. Fig. 6 is a circuit diagram of the transformer apparatus shown in Fig. 5. The transformer apparatus 500 comprises a toroidal core 505, a primary winding 510, a plurality of secondary windings 520, 525, 530 and 535, a protection tape 563, a metal foil 566, an UL tube 560, an epoxy resin 570, a base 580, and a plurality of lead terminals 511, 512, 521, 522, 526, 527, 531, 532, 536 and 537. The epoxy resin 570 is utilized for mounting the toroidal core 505 onto the base 580.

[0021] Similarly, the primary winding 510 having a predetermined number of turns is wound around the toroidal core 505 at one side. The primary winding 510 has two lead terminals 511 and 512 to which an AC power source is applied. The plurality of secondary windings 520, 525, 530 and 535 are stranded together to form a winding 550.

[0022] The winding 550 having another predetermined number of turns is wound around the toroidal core 505 at the other side opposite to the primary winding 510, which means that the secondary windings 520, 525, 530 and 535 are all having same predetermined number of turns as that of the winding 550. The secondary winding 520 has two lead terminals 521 and 522 which are connected to a first load (not shown). The secondary winding 525 has two lead terminals 526 and 527 which are connected to a second load (not shown) . The secondary winding 530 has two lead terminals 531 and 532 which are connected to a third load (not shown). The secondary winding 535 has two lead terminals 536 and 537 which are connected to a fourth load (not shown).

[0023] The wires of the primary winding 510, the secondary windings, 520, 525, 530 and 535 can be triple-insulation wires, oleoresinous enameled wires, synthetic enameled wires, polyurethane enameled wires, polyester enameled wires, polyester-imide enameled wires, nylon coated polyurethane enameled wires, or tinnable polyester enameled wires.

[0024] The protection tape 563 is an insulation tape and is wrapped around the toroidal core 505 together with the primary winding 510 and the secondary winding 520 in the manner shown in Fig. 5 for protecting the primary winding 510 and the secondary winding 520 against erosion. In a manner similar to that described above, the primary winding 510 and the secondary winding 520 are substantially enclosed by the protection tape 563 although the schematic diagram of Fig. 5 is not convenient to clearly demonstrate the protection architecture. The protection tape 563 can be a polyethylene tape. The metal foil 566 is used to enclose the protection tape 563 in the manner shown in Fig. 5 so that external electrical noises such as electromagnetic waves cannot penetrate to affect the operations of the toroidal core 505, the primary winding 510 and the secondary winding 520. The metal foil 566 can be a copper foil, an aluminum foil, or a tin foil. The UL tube 560 enfolding metal foil 566 is water resistant and offers rudimentary protection against water or moisture, which in turn protects the metal foil 566 against oxidation and corrosion. In accordance with another embodiment of the present invention, the bottom edge of the protection tape 563, the metal foil 566, or the UL tube 560 can be glued to the base 380 by another epoxy resin (not shown) so that the toroidal core 505 together with the primary winding 510 and the secondary windings 520, 525, 530 and 535 can be sealed closely within the space enclosed by the protection tape 563, the metal foil 566, or the UL tube 560, and the base 580.

[0025] Again, compared with the conventional transformer apparatus 100 shown in Fig. 1, the transformer apparatus 500 according to the present invention offers two extra protection shields for reinforcing structure of the transformer apparatus and preventing penetration of external electrical noises. Moreover, a plurality of secondary windings stranded together can provide identical and stable induction voltages for a plurality of loads. Furthermore, the two extra protection shields by the copper foil and the polyethylene tape are actually a cost-effective means for solving the prior art problems.

[0026] Please refer to Fig. 7. Fig. 7 illustrates a flowchart depicting a transformer shielding method for generating a shielded transformer apparatus in accordance with a preferred embodiment of the present invention. The transformer shielding method comprises the following steps:

Step S701: wind a primary winding using an insulated wire around a toroidal core at one side;

Step S702: wind a secondary winding using an insulated wire around the toroidal core at the other side opposite to the primary winding;

Step S703: mount the toroidal core onto a base by an epoxy resin;

Step S704: wrap the primary winding and the secondary winding by a protection tape;

Step S705: enclose the protection tape by a metal foil; and

Step S706: enfold the metal foil by an UL tube.

[0027] The step S701 may mean to wind a triple-insulation wire to form the primary winding around the toroidal core at one side. The step S702 may mean to wind a triple-insulation wire to form the secondary winding around the toroidal core at the other side opposite to the primary winding. The step S702 may further mean to wind another secondary winding using an insulated wire around the toroidal core at the other side opposite to the primary winding and the secondary windings may be stranded together. The step S704 may mean to wrap the primary winding and the secondary winding by a polyethylene tape. The step S704 may further mean to glue the bottom edge of the protection tape to the base by another epoxy resin. The step S705 may mean to enclose the protection tape by a copper foil, an aluminum foil, or a tin foil. The step S705 may further mean to bend-over the bottom edge of the metal foil outward external to the toroidal core for forming an U-shaped structure at the bottom edge and leave a gap of about 1mm between the bottom edge of the metal foil and the base. The step S705 may further mean to glue the bottom edge of the metal foil to the base by another epoxy resin. The step S706 may further mean to glue the bottom edge of the UL tube to the base by another epoxy resin.

[0028] Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.

Claims

1. A transformer apparatus (300; 500) comprising:

a toroidal core (305; 505);

a primary winding (310; 510), wound around the toroidal core (305; 505) at one side;

at least one secondary winding (320; 520, 525, 530, 535), wound around the toroidal core (305; 505) at the other side opposite to the primary winding (310; 510);

a protection tape (363; 563) wrapping around the primary winding (310; 510) and the at least one secondary winding (320; 520, 525, 530, 535);

a metal foil (366; 566) enclosing the protection tape (363; 563); and

an UL tube (360; 560) enfolding the metal foil (366; 566), wherein the UL tube (360; 560) is water resistant and offers protection against water or moisture.

2. The transformer apparatus (300; 500) of claim 1, the transformer apparatus (300; 500) further comprising a base (380; 580), wherein the toroidal core (305; 505) is mounted onto the base (380; 580) by an epoxy resin (370; 570).

3. The transformer apparatus (300; 500) of claim 1,
wherein the wire of the primary winding (310; 510) is a triple-insulation wire, an oleoresinous enameled wire, a synthetic enameled wire, a polyurethane enameled wire, a polyester enameled wire, a polyester-imide enameled wire, a nylon coated polyurethane enameled wire, or a tinnable polyester enameled wire.

4. The transformer apparatus (300; 500) of claim 1, wherein the wire of the at least one secondary winding (320; 520, 525, 530, 535) is a triple-insulation wire, an oleoresinous enameled wire, a synthetic enameled wire, a polyurethane enameled wire, a polyester enameled wire, a polyester-imide enameled wire, a nylon coated polyurethane enameled wire, or a tinnable polyester enameled wire.

5. The transformer apparatus (300; 500) of claim 1, wherein the transformer apparatus (300; 500) comprises a plurality of secondary windings (520, 525, 530, 535) being stranded together.

6. A transformer shielding method for generating a shielded transformer apparatus (300; 500), comprising:

winding a primary winding (310; 510) using an insulated wire around a toroidal core (305; 505) at one side;

winding at least one secondary winding (320; 520, 525, 530, 535) using an insulated wire around the toroidal core (305; 505) at the other side opposite to the primary winding (310; 510);

mounting the toroidal core (305; 505) onto a base (380; 580) by an epoxy resin (370; 570);

wrapping the primary winding (310; 510) and the at least one secondary winding (320; 520, 525, 530, 535) by a protection tape (363; 563);

enclosing the protection tape (363; 563) by a metal foil (366; 566); and

enfolding the metal foil (366; 566) by an UL tube (360; 560), wherein the UL tube (360; 560) is water resistant and offers protection against water or moisture.

7. The transformer shielding method of claim 6, the transformer shielding method comprising winding a plurality of secondary windings (520, 525, 530, 535) using an insulated wire around the toroidal core (305; 505) at the other side opposite to the primary winding (310; 510).

8. The transformer shielding method of claim 6, wherein winding a secondary winding (320; 520, 525, 530, 535) using an insulated wire around the toroidal core (305; 505) at the other side opposite to the primary winding (310; 510) means winding a triple-insulation wire to form the at least one secondary winding (320; 520, 525, 530, 535) around the toroidal core (305; 505) at the other side opposite to the primary winding (310; 510).

Ansprüche

1. Eine Transformatorvorrichtung (300; 500) aufweisend:

einen Ringkern (305; 505);

eine Primärwicklung (310; 510), die an einer Seite um den Ringkern (305; 505) gewickelt ist;

mindestens eine Sekundärwicklung (320; 520, 525, 530, 535), die an der anderen Seite gegenüber der Primärwicklung (310; 510) um den Ringkern (305; 505) gewickelt ist;

ein Schutzband (363; 563), welches die Primärwicklung (310; 510) und die mindestens eine Sekundärwicklung (320; 520, 525, 530, 535) umhüllt;

eine Metallfolie (366; 566), die das Schutzband (363; 563) umschließt; und

eine UL-Röhre (360; 560), welche die Metallfolie (366; 566) umfasst, wobei die UL-Röhre (360; 560) wasserbeständig ist und Schutz vor Wasser oder Feuchtigkeit bietet.

2. Die Transformatorvorrichtung (300; 500) gemäß Anspruch 1, wobei die Transformatorvorrichtung (300; 500) ferner eine Basis (380; 580) aufweist, wobei der Ringkern (305; 505) durch ein Epoxidharz (370; 570) auf die Basis (380; 580) montiert ist.

3. Die Transformatorvorrichtung (300; 500) gemäß Anspruch 1, wobei der Draht der ersten Primärwicklung (310; 510) ein Dreifach-Isolierdraht, ein Ölharz-Lackdraht, ein Synthetik-Lackdraht, ein Polyurethan-Lackdraht, ein Polyester-Lackdraht, ein Polyesterimid-Lackdraht, ein nylonbeschichteter Polyurethan-Lackdraht oder ein verzinnbarer Polyester-Lackdraht ist.

4. Die Transformatorvorrichtung (300; 500) gemäß Anspruch 1, wobei der Draht der mindestens einen Sekundärwicklung (320; 520, 525, 530, 535) ein Dreifach-Isolierdraht, ein Ölharz-Lackdraht, ein Synthetik-Lackdraht, ein Polyurethan-Lackdraht, ein Polyester-Lackdraht, ein Polyesterimid-Lackdraht, ein nylonbeschichteter Polyurethan-Lackdraht oder ein verzinnbarer Polyester-Lackdraht ist.

5. Die Transformatorvorrichtung (300; 500) gemäß Anspruch 1, wobei die Transformatorvorrichtung (300; 500) eine Mehrzahl von Sekundärwicklungen (520, 525, 530, 535) aufweist, welche zusammen verlitzt sind.

6. Ein Transformator-Abschirmverfahren zum Erzeugen einer Transformator-Abschirmvorrichtung (300; 500) aufweisend:

Wickeln einer Primärwicklung (310; 510) unter Verwendung eines isolierten Drahtes um einen Ringkern (305; 505) an einer Seite;

Wickeln mindestens einer Sekundärwicklung (320; 520, 525, 530, 535) unter Verwendung eines isolierten Drahtes um den Ringkern an der anderen Seite gegenüber der Primärwicklung (310; 510);

Montieren des Ringkerns (305; 505) auf eine Basis (380; 580) durch ein Epoxidharz (370; 570)

Umhüllen der Primärwicklung (310; 510) und der mindestens einen Sekundärwicklung (320; 520, 525, 530, 535) durch ein Schutzband (363; 563);

Umschließen des Schutzbandes (363; 563) durch eine Metallfolie (366; 566); und

Umfassen der Metallfolie (366; 566) durch eine UL-Röhre (360; 560), wobei die UL-Röhre (360; 560) wasserbeständig ist und Schutz vor Wasser oder Feuchtigkeit bietet.

7. Das Transformator-Abschirmverfahren gemäß Anspruch 6, wobei das Transformator-Abschirmverfahren aufweist das Wickeln einer Mehrzahl von Sekundärwicklungen (520, 525, 530, 535) unter Verwendung eines isolierten Drahtes um den Ringkern (305; 505) an der anderen Seite gegenüber der Primärwicklung (310; 510).

8. Das Transformator-Abschirmverfahren gemäß Anspruch 6, wobei das Wickeln einer Sekundärwicklung (320; 520, 525, 530, 535) unter Verwendung eines isolierten Drahtes um den Ringkern (305; 505) an der anderen Seite gegenüber der Primärwicklung bedeutet, dass ein Dreifach-Isolierdraht gewickelt ist, um die mindestens eine Sekundärwicklung (320; 520, 525, 530, 535) um den Ringkern (305; 505) an der anderen Seite gegenüber der Primärwicklung (310; 510) zu bilden.

Revendications

1. Appareil de transformateur (300 ; 500) comprenant :

- un noyau toroïdal (305 ; 505) ;

- un enroulement primaire (310 ; 510), enroulé autour du noyau toroïdal (305 ; 505) d'un côté ;

- au moins un enroulement secondaire (320 ; 520, 525, 530, 535), enroulé autour du noyau toroïdal (305 ; 505) de l'autre côté à l'opposé de l'enroulement primaire (310 ; 510) ;

- une bande de protection (363 ; 563) enroulée autour de l'enroulement primaire (310 ; 510) et dudit au moins un enroulement secondaire (320 ; 520, 525, 530, 535) ;

- une feuille métallique (366 ; 566) enfermant la bande de protection (363 ; 563) ; et

- un tube UL (360 ; 560) enveloppant la feuille métallique (366 ; 566), dans lequel le tube UL (360 ; 560) est résistant à l'eau et offre une protection contre l'eau ou l'humidité.

2. Appareil de transformateur (300 ; 500) selon la revendication 1, l'appareil de transformateur (300 ; 500) comprenant en outre une base (380 ; 580), dans lequel le noyau toroïdal (305 ; 505) est monté sur la base (380 ; 580) au moyen d'une résine époxy (370 ; 570).

3. Appareil de transformateur (300 ; 500) selon la revendication 1, dans lequel le fil de l'enroulement primaire (310 ; 510) est un fil à triple isolement, un fil émaillé oléorésineux, un fil émaillé synthétique, un fil émaillé avec polyuréthane, un fil émaillé avec polyester, un fil émaillé avec polyester-imide, un fil émaillé avec polyuréthane revêtu de nylon, un fil émaillé avec polyester étamable.

4. Appareil de transformateur (300 ; 500) selon la revendication 1, dans lequel le fil dudit au moins un enroulement secondaire (320 ; 520, 525, 530, 535) est un fil à triple isolement, un fil émaillé oléorésineux, un fil émaillé synthétique, un fil émaillé avec polyuréthane, un fil émaillé avec polyester, un fil émaillé avec polyester-imide, un fil émaillé avec polyuréthane revêtu de nylon, ou un fil émaillé avec polyester étamable.

5. Appareil de transformateur (300 ; 500) selon la revendication 1, dans lequel l'appareil de transformateur (300 ; 500) comprend une pluralité d'enroulements secondaires (520, 525, 530, 535) toronnés les uns avec les autres.

6. Procédé de blindage de transformateur pour générer un appareil de transformateur blindé (300 ; 500), comprenant :

- l'enroulement d'un enroulement primaire (310 ; 510) en utilisant un fil isolé autour d'un noyau toroïdal (305 ; 505) d'un côté ;

- l'enroulement d'au moins un enroulement secondaire (320 ; 520, 525, 530, 535) en utilisant un fil isolé autour du noyau toroïdal (305 ; 505) de l'autre côté à l'opposé de l'enroulement primaire (310 ; 510) ;

- le montage du noyau toroïdal (305 ; 505) sur une base (380 ; 580) au moyen d'une résine époxy (370 ; 570) ;

- l'enroulement d'une bande de protection (363 ; 563) autour de l'enroulement primaire (310 ; 510) et dudit au moins un enroulement secondaire (320 ; 520, 525, 530, 535) ;

- l'enfermement de la bande de protection (363 ; 563) par une feuille métallique (366 ; 566) ; et

- l'enveloppement de la feuille métallique (366 ; 566) par un tube UL (360 ; 560), dans lequel le tube UL (360 ; 560) est résistant à l'eau et offre une protection contre l'eau ou l'humidité.

7. Procédé de blindage de transformateur selon la revendication 6, le procédé de blindage de transformateur comprenant l'enroulement d'une pluralité d'enroulements secondaires (520, 525, 530, 535) en utilisant un fil isolé autour du noyau toroïdal (305 ; 505) de l'autre côté à l'opposé de l'enroulement primaire (310 ; 510).

8. Procédé de blindage de transformateur selon la revendication 6, dans lequel l'enroulement d'un enroulement secondaire (320 ; 520, 525, 530, 535) en utilisant un fil isolé autour du noyau toroïdal (305 ; 505) de l'autre côté à l'opposé de l'enroulement primaire (310; 510) signifie l'enroulement d'un fil à triple isolement pour former ledit au moins un enroulement secondaire (320 ; 520, 525, 530, 535) autour du noyau toroïdal (305 ; 505) de l'autre côté à l'opposé de l'enroulement primaire (310 ; 510).

Drawing