DE102023000998A1 - Transformer with toroidal core - Google Patents

Abstract

Transformer with a toroidal core, in particular with a toroidal toroidal core, wherein the transformer has a ring winding, in particular wherein the ring axis of the ring winding is aligned coaxially to the ring axis of the toroidal core, wherein the transformer has a toroidal winding on the toroidal core, in particular wherein the toroidal winding has a primary winding and a Secondary winding, in particular which are wound on the toroidal core, the toroidal winding being arranged between the toroidal core and the toroidal winding.

Description

The invention relates to a transformer with a toroidal core.

From the WO 2020/001811 A1 The closest prior art is a toroidal transformer.

From the US4 210 859 A an orthogonal winding is known.

From the CA 3009929 A1 A toroidal winding with an internal winding is known.

From the EP 2 603 920 B1 a transformer is known.

From the US 2008 / 0 204 180 A1 A transformer with a toroidal core is known.

From the US 2002 / 0 017 976 A1 an inductive component with a toroidal core is known.

From the JP 4 523 389 B2 A transformer with a toroidal core is known.

From the DE 10 2012 202 472 A1 The design of ferrite layers is known.

From the EP 1 933 339 A2 Components having a toroidal core are known.

From the EP 3 428 937 A1 A hollow toroidal magnetic power unit is known.

From the US 2005/ 0 110 605 A1 a controllable transformer is known.

From the JP 2001- 167 935 A a toroidal coil is known.

From the JP S60-32 313 A A toroidal coil is also known.

From the JP S60-32 313 A a magnetic nucleus is known.

From the DE 10 2019 003 843 A1 A transformer with a toroidal core is known.

The invention is therefore based on the object of designing a transformer with a toroidal core and a system for electrically supplying a load to be compact.

According to the invention, the object is achieved in the transformer according to the features specified in claim 1.

Important features of the invention in the transformer, in particular with a toroidal toroidal core, are that the transformer has a ring winding, in particular the ring axis of the ring winding is aligned coaxially to the ring axis of the toroidal core,
wherein the transformer has a toroidal winding on the toroidal core, in particular wherein the toroidal winding has a primary winding and a secondary winding, in particular which are wound on the toroidal core,
wherein the ring winding is arranged between the ring core and the toroidal winding, in particular is arranged radially between the ring core and the toroidal winding,
in particular, the toroidal core is made of ferrite,
in particular where the radial direction is related to the ring axis.

The advantage here is that the toroidal core can be used efficiently. This is because the toroidal winding and the ring winding are orthogonal to one another and can therefore be operated undisturbed by each other as long as the toroidal core is not operated in saturation.

The toroidal winding can be used in a gyrator. The ring winding can be used as an inductor of an electronic circuit that includes the gyrator.

The two ring windings are arranged so that they are easily accessible to a cooling air flow and efficient heat dissipation can therefore be achieved.

In an advantageous embodiment, the ring core is designed as a rotating body, which is produced from a U-shaped base structure,
in particular, the axis of rotational symmetry of the rotating body is aligned coaxially with the ring axis of the ring winding,
in particular, wherein the U is aligned open radially outwards and / or the legs of the U are arranged radially outside the yoke of the U connecting the legs of the U,
in particular, wherein the ring winding is accommodated in a radially directed recess of the toroidal core and/or wherein the ring winding is accommodated in the recess created by the U,
in particular, the ring winding being arranged radially outside the ring core, in particular at least in the axial region covered by the ring winding in the axial direction,
in particular, the ring winding is axially limited on both sides by the legs of the U. The advantage here is that simple production can be achieved. In addition, the toroidal core can be designed in two parts, so that the two toroidal core parts can be designed to be identical and/or identical to one another are. The ring winding is axially limited by the ring core.

In an advantageous embodiment, the ring core is designed as a rotating body, which is produced from a T-shaped or E-shaped base structure,
in particular, the axis of rotational symmetry of the rotating body is aligned coaxially with the ring axis of the ring winding,
wherein a first winding part of the ring winding is axially spaced from a second winding part of the ring winding by means of a leg of the T or by means of the middle leg of the E. The advantage here is that the ring winding can be implemented in two spaced-apart partial windings, in particular winding parts, which can be spaced apart from one another by means of the ferrite material of the ring core. In the T-shaped design, the holding parts limit the partial windings axially. In the E-shaped design, the toroidal core limits the partial windings themselves axially.

In an advantageous embodiment, the winding wire of the ring winding extends perpendicular to the direction of extension of the closest winding wire region of the toroidal winding. The advantage here is that efficient utilization of the toroidal core can be achieved.

In an advantageous embodiment, the main magnetic field generated by the ring winding is aligned perpendicular to the main magnetic field generated by the toroidal winding. The advantage here is that efficient utilization of the toroidal core can be achieved.

In an advantageous embodiment, the toroidal winding has partial windings, in particular the primary winding and the secondary winding each have partial windings,
wherein the partial windings are spaced apart from one another in the circumferential direction, in particular with respect to the ring axis of the toroidal core, and in particular are regularly spaced apart from one another. The advantage here is that voltage gaps are sufficiently large.

In an advantageous embodiment, the transformer has a flux guide body which is arranged outside the spatial area wrapped by the primary winding and the secondary winding, in particular and outside the toroidal core. The advantage here is that the leakage flux is bundled by means of the flux guide body and the leakage inductance is thus increased. In addition, the emergence of field lines is reduced, i.e. magnetic shielding is achieved. This in turn means that electrically conductive materials, such as housing parts made of aluminum, in the area around the transformer only reduce its leakage inductance very slightly.

In an advantageous embodiment, the flow guide body is designed in one piece, in particular in one piece, or in several parts, in particular in several pieces. The advantage here is that simple, cost-effective production is possible.

In an advantageous embodiment, the flux guide body has a second ferrite ring, which is arranged coaxially to the ring core,
wherein the second ferrite ring is axially spaced from the toroidal core including the primary winding and secondary winding, in particular the axial area covered by the toroidal core including the primary winding and secondary winding is spaced from the axial area covered by the second ferrite core,
and/or wherein the wall thickness of the second ferrite ring is smaller in the axial direction than in the radial direction,
and/or wherein the radial spacing region covered by the second ferrite core is encompassed by or overlaps with the radial spacing region covered by the toroidal core together with the primary winding and secondary winding. The advantage here is that the stray flux is concentrated even further.

In an advantageous embodiment, the flux guide body has a first ferrite ring, which is arranged coaxially to the ring core,
wherein the wall thickness of the first ferrite ring is smaller in the radial direction than in the axial direction
and/or wherein the radial distance area covered by the first ferrite core is spaced apart from the radial distance area covered by the toroidal core including the primary winding and secondary winding,
and/or wherein the axial region covered by the first ferrite core is encompassed by or overlaps with the axial region covered by the toroidal core together with the primary winding and secondary winding. The advantage here is that the stray flux is concentrated even further.

• - wobei die Wandstärke des weiteren Ferritrings in axialer Richtung kleiner ist als in radialer Richtung
• - und/oder wobei der vom weiteren Ferritkern überdeckte Radialabstandsbereich umfasst ist von dem vom Ringkern samt Primärwicklung und Sekundärwicklung überdeckten Radialabstandsbereich oder mit ihm überlappt.

In an advantageous embodiment, the flux guide body has a further ferrite ring, which is arranged coaxially to the toroidal core and is arranged on the side of the toroidal core facing away from the second ferrite ring, the further ferrite ring being axially spaced from the toroidal core including the primary winding and secondary winding, in particular from the toroidal core axial area covered by the primary winding and secondary winding is spaced from the axial area covered by the further ferrite core,
in particular

• - The wall thickness of the further ferrite ring is smaller in the axial direction than in the radial direction
• - and/or wherein the radial distance area covered by the further ferrite core is encompassed by or overlaps with the radial distance area covered by the toroidal core together with the primary winding and secondary winding.

The advantage here is that the stray flux is concentrated even further.

In an advantageous embodiment, the first ferrite ring is composed of a large number of ferrite plates, in particular which are each tangentially aligned.

In an advantageous embodiment, the ferrite plates are arranged on flat surface areas, in particular contact surfaces, of a carrier part, in particular by means of double-sided adhesive tape. The advantage here is that simple production is possible.

In an advantageous embodiment, the carrier part, in particular the first plastic injection-molded part, has a radially projecting collar region on its axial end region facing away from the first ferrite ring, which is connected to a holding plate, in particular by means of screws. The advantage here is that simple production is possible.

In an advantageous embodiment, the carrier part, in particular the first plastic injection molded part, surrounds the toroidal core including the primary winding and secondary winding radially, in particular in a hood-like manner,
wherein a dome section of an air-guiding part, in particular a second plastic injection-molded part, projects into the spatial area radially surrounded by the toroidal core, so that an air flow conveyed by a fan is guided along the primary winding and secondary winding,
in particular, wherein the air guide part is connected to the holding plate, in particular by means of a screw. The advantage here is that the toroidal core can be efficiently cooled with a cooling air flow. This cooling air flow flows around the ring winding and the toroidal winding.

In an advantageous embodiment, holding parts are arranged on the end faces of the toroidal core, each of which has axially excellent support posts,
wherein the turns of the toroidal winding, in particular the primary winding and the secondary winding, are guided and/or held in recesses formed in the circumferential direction between the support posts,
in particular, the holding parts are formed as plastic ring parts with axially projecting support posts, which are connected to the air guide parts or the support part with the fan cover. The advantage here is that the toroidal winding is wound in a guided manner.

In an advantageous embodiment, the holding plate is trough-shaped and/or trough-shaped and has continuous slots on its side surfaces,
in particular, the bottom of the tub or trough deflects the air flow towards the side surfaces, in particular has no continuous recesses allowing the air flow to pass through. The advantage is that stable mounting and attachment can be achieved.

In an advantageous embodiment, a fan cover is formed on the carrier part or connected to the carrier part on the axial end region of the carrier part facing away from the collar area,
wherein the fan cover concentrates, in particular directs, the air flow conveyed by a fan radially inwards. The advantage here is that the cooling air flow can be passed efficiently between the carrier part and the toroidal core and both windings can therefore be heat-heated. In addition, a partial air flow is passed radially inside the toroidal core in order to also cool the radially innermost winding areas of the toroidal winding.

Further advantages result from the subclaims. The invention is not limited to the combination of features of the claims. For the person skilled in the art, further sensible combination options of claims and/or individual claim features and/or features of the description and/or the figures arise, in particular from the task and/or the task posed by comparison with the prior art.

• In der 1 ist ein erfindungsgemäßer Ringkerntransformator mit Primärwicklung 21 und Sekundärwicklung 22 in Schrägansicht explodiert dargestellt.
• In der 2 ist im Unterschied zur 1 sowohl die Primärwicklung 21 als auch die Sekundärwicklung 22 ausgeblendet, so dass die Ringwicklung 20 sichtbar wird.
• In der 3 sind die Wicklungen (20, 21, 22) der Ringkernwicklung explodiert dargestellt.
• In der 4 ist ein Querschnitt durch den Ringkerntransformator dargestellt.
• In der 5 ist eine zugehörige Draufsicht dargestellt.
• In der 6 ist ein weiterer Querschnitt dargestellt.

The invention will now be explained in more detail using schematic illustrations:

• In the 1 A toroidal core transformer according to the invention with primary winding 21 and secondary winding 22 is shown exploded in an oblique view.
• In the 2 is different from 1 both the primary winding 21 and the secondary winding 22 are hidden so that the ring winding 20 becomes visible.
• In the 3 the windings (20, 21, 22) of the toroidal core winding are shown exploded.
• In the 4 a cross section through the toroidal transformer is shown.
• In the 5 an associated top view is shown.
• In the 6 another cross section is shown.

As shown in the figures, a toroidal core of the toroidal core transformer according to the invention is composed of two toroidal core parts 30 and 31 and is wound with a ring winding 20, the ring axis of which is aligned coaxially with the ring axis of the toroidal core.

The ring core formed from the two ring core parts 30 and 31 has a radial recess in which the ring winding 20 is accommodated.

A holding part 8, which is preferably made of plastic, in particular as a plastic injection molded part, is placed on each of the two axial end regions of the toroidal core.

The respective holding part 8 has recesses spaced apart from one another in the circumferential direction, in particular evenly spaced, radially and/or axially directed, which function as a guide for a winding arrangement of the toroidal core transformer.

The winding arrangement includes a primary winding 21 and a secondary winding 22, the turns of which are separated from one another in the circumferential direction. In particular, the two windings 21 and 22 do not overlap.

Preferably, the secondary winding 22 is spaced apart from the primary winding 21 in the circumferential direction and counter to the circumferential direction.

In further exemplary embodiments according to the invention, the primary winding 21 and the secondary winding 22 are each designed in partial windings, which are then spaced apart from one another in the circumferential direction and counter to the circumferential direction.

On the holding part 8 there is an eyelet 32 which projects radially outwards and is used as an axial boundary or contact surface in the manufacture of the toroidal core transformer in order to set the adhesive gap between the two toroidal core parts 30 and 31 in a defined manner, so that the adhesive gap can then be filled with adhesive and after the adhesive has hardened, the axial length of the toroidal core including the attached holding parts 8 corresponds as closely as possible to a target value. In this way, the axial length of the winding arrangement can then be produced very precisely, in particular with a high level of manufacturing precision

The winding arrangement is radially surrounded by a first ferrite ring 24, which is preferably composed of individual ferrite plates which are placed, in particular glued, onto flat contact surfaces 5 of a carrier part 6.

The support part 6 is shaped like a hood and is connected at its first axial end region to a fan cover 7, in particular with a square pyramid section. An electric motor-driven fan can be accommodated in the fan cover 7, so that the air flow conveyed by the fan is guided by the fan cover 7 in such a way that the air flow in the axial direction, in particular in the direction of the ring axis of the toroidal core transformer, through the carrier part 6 and through the toroidal core flows through. In this way, the heat dissipation of the toroidal core can be guaranteed.

In addition, an air guide part 2 is arranged on the side of the toroidal core facing away from the fan cover 7, on which a dome section 3 protrudes axially towards the fan cover 7, the dome section 3 protruding into the interior area of the toroidal core.

The dome section 3 is shaped as a body of revolution, the axis of rotational symmetry of which is aligned coaxially with the ring axis of the toroidal core.

The conveyed air flow is thus driven between the ring core and the dome section 3, so that the air flow is guided as completely as possible past the ring core and efficient heat dissipation can thereby be achieved.

The dome section 3 is arranged on a perforated disc-shaped base section which has axially continuous recesses 9 which are spaced apart from one another irregularly, in particular unevenly, in the circumferential direction, so that the elevations which rise in the axial direction on the holding part 8 protrude into the recesses 9 and thereby ensure positioning and fixing the holding part 8 relative to the air guiding part 2 in a form-fitting manner.

The air guide part 2 is accommodated in a trough-like holding plate 1, which also has axially projecting pin areas for positive positioning and/or delimitation of the air guide part 2 in the circumferential direction. For this purpose, the maximum outer radius is not constant but depends on the circumferential angle. In this way, the pin area secures the air guiding part 2 in a form-fitting manner.

The ring winding 20 is therefore wound on the ring core and the winding arrangement is radially outside the ring winding 20.

All windings, i.e. the ring winding 20 and the winding arrangement, in particular the primary winding and the secondary winding, are surrounded by the air flow that is driven by the fan, since they are arranged radially on the outside of the ring core and not on the inside in the ring core. This enables efficient heat dissipation of all windings.

However, the winding wires of the winding arrangement run in the axial direction, i.e. perpendicular and/or orthogonal to the ring winding 20, the winding wire of which extends essentially in the circumferential direction. The winding arrangement is a toroidal winding in contrast to the ring winding 20.

Likewise, the field lines are essentially orthogonal to one another, particularly in the toroidal core and in the first ferrite ring 24. The toroidal core is made of ferrite. As long as the ferrite material does not become saturated, the windings can be operated without interference from one another.

In addition, a second ferrite core 23 is provided, which is preferably axially spaced from the first ferrite core 24 and is arranged radially within the first ferrite core 24.

The second ferrite core 23 is shaped like a perforated disk and is preferably formed in two parts, in particular from two parts that are identical to one another.

The winding arrangement is therefore also loaded with ferrite material on the end face, i.e. on the end face of the winding arrangement facing away from the air guiding part 2.

As in 4 shown, the ring winding 20 is arranged in a radial recess of the ring core formed from the ring core parts, in particular ferrite parts, 30 and 31. The ring winding 20 is preferably arranged symmetrically.

The two toroidal core parts (30, 31) are identical to one another.

Therefore, the ring core, i.e. the coil core of the ring winding 20, resembles a rotating body whose generating base structure is U-shaped.

The ring winding 20 is delimited in the axial direction by the first ring core part 30 and against the axial direction by the second ring core part 31.

In particular, the leakage flux is increased by the first ferrite core 24 and the second ferrite core 23.

Thus, by arranging additional ferrite material outside the windings, in particular outside the spatial area wrapped by the windings, the leakage flux is specifically increased and thus a desired value can also be achieved for a stray field inductance concentrated on the secondary side.

The first ferrite ring 24 is designed with a greater wall thickness in the radial direction than in the axial direction.

On the other hand, the second ferrite ring 23 is designed with a wall thickness that is greater in the radial direction than in the axial direction.

The ring core and each of the two ferrite rings (24, 23) are coaxially aligned with one another, so in particular they have the same ring axis. The composition of the first ferrite ring 24 from individual plates enables cost-effective production. It is also advantageous that the resulting mechanical stresses do not lead to the destruction of the ferrite plates when there are temperature fluctuations during operation.

The fan cover 7 is preferably designed as a square pyramid section.

The fan cover 7 is therefore designed in a funnel shape and concentrates the air flow conveyed by the fan into the fan cover 7 radially inwards, so that the air flow is directed onto the toroidal core.

The windings (20, 21, 22) are thus arranged on the toroidal core in the air flow and can be cooled.

The centrally axially rising dome section 3 of the air guiding part 2 is fixed to the holding plate 1 with a screw passing through the dome section 3 in such a way that the dome section protrudes into the spatial area surrounded by the toroidal core. The air flow is thus directed more effectively along the windings (21, 22). On the side of the air guide part 2 facing away from the toroidal core, the second ferrite ring 23 is arranged, which also guides the leakage flux in sections.

The holding plate 1 is made of aluminum.

Improved magnetic shielding is also achieved by means of the additional ferrite material, in particular by means of the first, second and third ferrite rings (22, 23, 41). Eddy currents can therefore be reduced in the vicinity of electrically conductive parts. In this way the Heating of such parts can be reduced and therefore the risk of fire.

The holding plate 40 is trough-shaped and has slots on its sides, in particular on the side walls of the trough, so that the air flow conveyed by the fan 50 can be directed outwards radially.

The radial direction and the circumferential direction are always related to the ring axis of the toroidal core 30, which characterizes the axial direction.

As in 6 is shown, the secondary winding has a first and a second partial winding, which are spaced apart from one another in the circumferential direction relative to the toroidal core, with turns of the primary winding being arranged in the spacing area.

It is therefore important that the partial windings of the secondary winding are spaced apart from one another in the circumferential direction, are electrically connected to one another in series or parallel, and the intermediate regions formed by the spacing have turns of the primary winding. The additional ferrite cores bundle field lines that emerge to the outside.

In further exemplary embodiments according to the invention, the secondary winding is not formed from two, but from more than two partial windings, which are connected in series and/or parallel to one another.

The number of turns of the partial windings is preferably the same size. The partial windings are arranged symmetrically with respect to the primary winding.

Both holding parts 8 have the eyelets 32 on their outer circumference, to which winding wires led out of the windings are attached, in particular a respective winding wire is passed through the respective eyelet 32. When producing the toroidal core, before winding the toroidal core 30 and before adhesively connecting the toroidal core parts and/or holding parts 8, the eyelets 32 are used to fasten spacer means, which axially space the toroidal core parts or the holding parts 48 from one another. During adhesive bonding, in particular hardening of an adhesive, the spacing is thus secured and fixed.

After the adhesive connection has been made, the spacer means are removed and the winding is then carried out, with the end regions of winding wires being attached to the eyelets 32.

The holding parts 8 also each have a circumferential channel in which winding wire is inserted for connecting partial windings in the circumferential direction. In further exemplary embodiments according to the invention, another flow-conducting material is used instead of ferrite.

In further exemplary embodiments according to the invention, a third ferrite core is arranged on the other end face. However, other positions of the ferrite rings (24, 23) are also possible.

In further exemplary embodiments according to the invention, a third ferrite ring, which is preferably structurally identical to the first ferrite ring 24, is arranged on the side of the toroidal core facing away from the first ferrite ring 24, in particular symmetrically to the plane of symmetry and/or ring plane of the toroidal core.

As in 7 shown, alternatively a T-shaped base structure can also be advantageously used, in which case the ring winding 20 is designed in two parts. A first winding part 72 of the ring winding 20 is thus axially limited by the first holding part 8 and the second winding part 73 of the ring winding 20 is axially limited by the second holding part 8.

The radial depression after 4 In this alternative embodiment, it is designed in two parts, so that each winding part (72, 73) is accommodated in the respective part of the recess.

The toroidal core is in the execution 7 composed of the two ring core parts 70 and 71, which have the respective part of the recess on the axially outer end region of the ring core instead of on its axial end region facing the other ring core part (70, 71).

In further exemplary embodiments according to the invention, instead of the T-shaped base structure, an E-shaped base structure is used, in which the parts of the two-part recess are spaced from the axial end of the respective ring core part (70, 71). A partial winding (72, 73) is therefore accommodated in each of the two parts of the two-part recess, in particular and axially limited.

Reference symbol list

1

retaining plate

2

Air control part

3

Cathedral section

4

Collar area

5

flat contact surfaces

6

Carrier part

7

Fan shroud, especially square pyramid section

8th

holding part

9

recesses

20

Ring winding

21

primary winding

22

Secondary winding

23

second ferrite ring

24

first ferrite ring

30

first toroidal core part

31

second toroidal core part

32

Eyelet, especially for positioning

70

first toroidal core part

71

second toroidal core part

72

first winding part of the ring winding

73

second winding part of the ring winding

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2020001811 A1 [0002]
• US 4210859 A [0003]
• CA 3009929 A1 [0004]
• EP 2603920 B1 [0005]
• US 20080204180 A1 [0006]
• US 20020017976 A1 [0007]
• JP 4523389 B2 [0008]
• DE 102012202472 A1 [0009]
• EP 1933339 A2 [0010]
• EP 3428937 A1 [0011]
• US 20050110605 A1 [0012]
• JP 2001167935 A [0013]
• JP S6032313 A [0014, 0015]
• DE 102019003843 A1 [0016]

Claims (16)

Transformer with a toroidal core, especially with a toroidal toroidal core, wherein the transformer has a ring winding, in particular wherein the ring axis of the ring winding is aligned coaxially with the ring axis of the ring core, wherein the transformer has a toroidal winding on the toroidal core, in particular wherein the toroidal winding has a primary winding and a secondary winding, in particular which are wound on the toroidal core, wherein the ring winding is arranged between the ring core and the toroidal winding, in particular is arranged radially between the ring core and the toroidal winding, in particular wherein the ring core is made of ferrite, in particular where the radial direction is related to the ring axis. Transformer after Claim 1 , characterized in that the ring core is designed as a rotating body which is produced from a U-shaped base structure, in particular wherein the rotational symmetry axis of the rotating body is aligned coaxially with the ring axis of the ring winding, in particular wherein the U is aligned open radially outwards and / or the Legs of the U are arranged radially outside of the yoke of the U connecting the legs of the U, in particular wherein the ring winding is received in a radially directed recess of the toroidal core and/or wherein the ring winding is received in the recess created by the U, in particular wherein the ring winding is arranged radially outside the ring core, in particular at least in the axial region covered by the ring winding in the axial direction, in particular wherein the ring winding is axially delimited on both sides by the legs of the U. Transformer after Claim 1 , characterized in that the ring core is designed as a rotating body which is produced from a T-shaped or E-shaped base structure, in particular wherein the rotational symmetry axis of the rotating body is aligned coaxially with the ring axis of the ring winding, with a first winding part of the ring winding by means of a leg of the T or by means of the middle leg of the E is axially spaced from a second winding part of the ring winding. Transformer according to at least one of the preceding claims, characterized in that the winding wire of the ring winding extends perpendicular to the direction of extension of the closest winding wire region of the toroidal winding, and / or that the main magnetic field generated by the ring winding is perpendicular to the main magnetic field generated by the toroidal winding is aligned. Transformer according to at least one of the preceding claims, characterized in that the toroidal winding has partial windings, in particular wherein the primary winding and the secondary winding each have partial windings, the partial windings being spaced apart from one another in the circumferential direction, in particular with respect to the ring axis of the toroidal core, in particular regularly from one another are spaced apart. Transformer according to at least one of the preceding claims, characterized in that the transformer has a flux guide body which is arranged outside the spatial area wrapped by the toroidal winding, in particular by the primary winding (21) and by the secondary winding (22), in particular and outside of the toroidal core. Transformer according to at least one of the preceding claims, characterized in that the flux guide body is designed in one piece, in particular in one piece, or in several parts, in particular in several pieces. Transformer according to at least one of the preceding claims, characterized in that the flux guide body has a second ferrite ring (23) which is arranged coaxially to the toroidal core, the second ferrite ring (23) being axially spaced from the toroidal core together with the toroidal winding, in particular the primary winding (21) and secondary winding (22), in particular the axial area covered by the toroidal core including the primary winding (21) and secondary winding (22), is spaced from the axial area covered by the second ferrite core, and / or the wall thickness of the second ferrite ring (23) in axial Direction is smaller than in the radial direction, and / or wherein the radial distance area covered by the second ferrite core is covered by or overlaps with the radial distance area covered by the toroidal core together with the toroidal winding, in particular primary winding (21) and secondary winding (21). Transformer according to at least one of the preceding claims, characterized in that the flux guide body has a first ferrite ring (24) which is arranged coaxially to the toroidal core, the wall thickness of the first ferrite ring (24) being smaller in the radial direction than in the axial direction and/or the radial spacing region covered by the first ferrite core being spaced apart is from the radial distance area covered by the toroidal core together with the toroidal winding, in particular primary winding (21) and secondary winding (21), and/or wherein the axial area covered by the first ferrite core (24) is covered by that from the toroidal core together with the toroidal winding, in particular primary winding ( 21) and secondary winding (22), covered or overlapped with the axial area. Transformer according to at least one of the preceding claims, characterized in that the flux guide body has a further ferrite ring which is arranged coaxially to the toroidal core and is arranged on the side of the toroidal core facing away from the second ferrite ring (23), the further ferrite ring being axially spaced from the toroidal core including the toroidal winding, in particular the primary winding (21) and secondary winding (22), in particular the axial area covered by the toroidal core including the primary winding (21) and secondary winding (22), is spaced from the axial area covered by the further ferrite core, in particular - where the wall thickness of the further ferrite ring is smaller in the axial direction than in the radial direction - and / or wherein the radial distance area covered by the further ferrite core is covered by or overlaps with the radial distance area covered by the toroidal core together with the toroidal winding, in particular the primary winding (21) and secondary winding (22). . Transformer according to at least one of the preceding claims, characterized in that the first ferrite ring (24) is composed of a plurality of ferrite plates, in particular which are each tangentially aligned, and / or that the ferrite plates are attached in particular to flat surface areas, in particular by means of adhesive tape on both sides Contact surfaces of a carrier part (6) are arranged. Transformer according to at least one of the preceding claims, characterized in that the carrier part (6), in particular the first plastic injection molded part, has a radially projecting collar region (4) on its axial end region facing away from the first ferrite ring (24), which is connected to a holding plate, especially using screws. Transformer according to at least one of the preceding claims, characterized in that the carrier part (6), in particular the first plastic injection molded part, radially surrounds the toroidal core together with the toroidal winding, in particular the primary winding (21) and secondary winding (22), in particular in a hood-like manner, with a dome section ( 3) an air guide part, in particular a second plastic injection molded part, protrudes into the spatial area radially surrounded by the annular core, so that an air flow conveyed by a fan is guided along the toroidal winding, in particular the primary winding (21) and secondary winding (22), in particular whereby the Air guide part (2) is connected to the holding plate, in particular by means of a screw. Transformer according to at least one of the preceding claims, characterized in that holding parts (8) are arranged on the end faces of the toroidal core, each of which has axially projecting support posts, the turns of the toroidal winding, in particular the primary winding (21) and the secondary winding (22) , are guided and/or held in recesses formed in the circumferential direction between the support posts, in particular wherein the holding parts are formed as plastic ring parts with axially projecting support posts which are connected to the air guiding parts or the support part (6) with the fan cover (7). Transformer according to at least one of the preceding claims, characterized in that the holding plate is trough-shaped and/or trough-shaped and has continuous slots on its side surfaces, in particular the bottom of the trough or trough deflects the air flow towards the side surfaces, in particular no continuous ones. has recesses that allow the air flow to pass through. Transformer according to at least one of the preceding claims, characterized in that at the axial end region of the carrier part (6) facing away from the collar region (4), a fan cover (7) is formed on the carrier part (6) or is connected to the carrier part (6), the Fan cover (7) concentrates, in particular directs, the air flow conveyed by a fan radially inwards.

Images