JP2000286138A - Non contact type transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a non contact type transformer which can be manufactured readily at a low cost and has high reliability by constituting a magnetic core of at least one coil of a pair of coils of a plurality of division piece cores, arranged in rotational symmetry of integral turns whose center of symmetry is the rotation axis. SOLUTION: In a non contact type transformer, each coil of an inside core 3 and an outside core forms a pair, thus constituting a transformer. The inside core 3 is tubular and in an outside core, eight rod-like division piece cores 1 whose length direction is the axial direction are arranged and fixed at equal angles in the inner surface of a tubular nonmagnetic holder 9. A coil with the division piece core 1 of an outside core is a primary side coil 5, and a coil with the inside core 3 is a secondary side coil 7. The primary side coil 5 is stored in a groove 14 of the division piece core 1, and the secondary coil 7 is stored in a groove 13. An outgoing line of the secondary side coil 7 is drawn out through the groove 15 formed in the axial direction of the inside core 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type transformer mounted on an axle of a steering wheel of an automobile to supply power and transmit signals.

[0002]

2. Description of the Related Art At present, there are a large number of automobiles with air conditioners and cruise control among widely spread automobiles. In the electrical systems of these vehicles, most of the operation systems are concentrated near the front panel or near the mounting portion of a steering wheel (hereinafter simply referred to as a steering wheel). For this reason, when operating the electrical system, one hand is temporarily removed from the steering wheel, and when the vehicle is running at high speed, the possibility of erroneous steering wheel operation and a large accident is increased.

[0003] Recently, automobiles in consideration of safety have been widespread in which this point has been improved, and a control switch of an electric system can be mounted on a steering wheel portion and operated without releasing the hand from the steering wheel. For the power supply / reception mechanism, a wire system was used, and a flexible wire having spring properties was used so that the wire would not be disconnected even by rotating the handle. FIG. 8 is a schematic configuration diagram of a power supply / reception unit in a conventional wired electrical system. In FIG. 8, a flat cable 21 holding and covering a plurality of wires in parallel is shown.
Is used. By making the flat cable 21 into a rounded shape, even if the handle is rotated, no tension is applied to the wire, so that the wire is not broken.

[0004]

However, the handle is
Since it is necessary to be able to rotate left and right equally, the flat cable 21 must be mounted so that the steering is neutral. The installation work of the flat cable 21 required much labor. In addition, the wires are rubbed during the work of attaching the power receiving and feeding unit, so that the durability is poor. Further, some users argue that comfort is impaired in the power supply / reception unit using the flat cable 21 in the electrical system because a sound is generated when the wire is rubbed or a slight resistance is generated when operating the steering wheel.

On the other hand, there has been proposed a system in which a non-contact type transformer is used for power supply and signal transmission by electromagnetic induction coupling, in contrast to the wired system. FIG. 9 is a configuration diagram of an example of a known non-contact type transformer. 9A is a plan view, and FIG. 9B is a side sectional view. In FIG. 9, the non-contact type transformer is composed of two cylindrical outer cores 4 and inner cores 3 which are concentrically overlapped with a slight gap, and a corresponding primary coil 5 and secondary coil 7 respectively. Have been. The primary side coil 5 and the secondary side coil 7 are concentric and oppose each other on the same plane. The primary coil 5 is formed in the groove 13 on the inner surface of the outer core 4, and the secondary coil 7 is formed in the groove 13 on the surface of the inner core 3. The outer core 4 is on the power supply / transmission side (primary side), and the inner core 3 is on the power reception / reception side (secondary side). The outer core 4 and the inner core 3 are usually made of Mn-
It is composed of a soft magnetic ferrite such as a Zn-based ferrite.

[0006] However, the conventional non-contact type transformer requires a large ferrite core. The ferrite core is liable to be warped or deformed even by sintering. In particular, it is difficult to produce a large ferrite core, and it is difficult to produce a non-contact type transformer, or a remarkably high cost has been required.

An object of the present invention is to provide a non-contact type transformer which can be easily and inexpensively manufactured, has high durability, and has high reliability.

[0008]

According to the present invention, there is provided a non-contact type transformer in which a pair of coils each having a magnetic core are closely opposed to each other on a circumference sharing a rotation axis. Coupling, the magnetic core of at least one of the paired coils is composed of a plurality of split piece cores arranged so as to have an integer number of rotational symmetry about the rotational axis as the center of symmetry. It is characterized by having. The split piece core is adjacent to another split piece core via a finite space.

[0009] In the non-contact type transformer of the present invention, the paired coils are arranged to face each other on the same plane perpendicular to the rotation axis. Further, the coil may be a non-contact type transformer in which a plurality of pairs are formed in the rotation axis direction.

The plurality of split cores are disposed on the surface or inner surface of a holder made of a nonmagnetic material having a circular or regular polygonal cross section, and the magnetic core including the split core is rotated. Overlap in the direction perpendicular to the axis to form the inner core and the outer core.

A groove formed in the magnetic core may be used. The groove formed along the circumference stores the coil, and the groove having the same directional component as the rotation axis can store the lead wire of the coil.

On the other hand, in the non-contact type transformer of the present invention, the paired coils are arranged so as to face each other in the direction of the rotation axis on a circumference having the same diameter centered on the rotation axis. Can also. The magnetic cores may be respectively fixed on a plane such as a pair of disks that face each other and share a rotation axis.

A non-contact type transformer in which a plurality of pairs of coils are formed in a radial direction about the rotation axis is also possible. Therefore, a coil formed on a plane such as a disk takes a circular or regular polygonal shape. If a soft magnetic ferrite or a metal magnetic material is used for the magnetic material core and a plurality of pairs are formed in the radial direction about the rotation axis, a non-contact type transformer capable of transmitting a plurality of signals can be obtained.

[0014]

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

FIG. 1 is a diagram showing an embodiment of a non-contact type transformer according to the present invention. FIG. 1A is a plan view, and FIG.
(B) is a side sectional view. In FIG. 1, coils each having an inner core 3 and an outer core are paired to form a non-contact type transformer. The inner core 3 has a cylindrical shape. The outer core is composed of a non-magnetic holder 9 formed of eight rod-shaped divided cores 1 whose length is in the axial direction.
Are arranged and fixed at an equal angle on the inner surface of the. FIG.
FIG. 2 is a perspective view of a split piece core 1 constituting an outer core of the non-contact type transformer shown in FIG. 1. A groove 14 for storing the primary coil 5 is formed in the split piece core 1. The split piece core 1 constituting the outer core may be formed by processing a cylindrical ferrite core and dividing the ferrite core. However, as shown in FIG. It is good to make a core and use it.

The split piece core 1 and the inner core 3 forming the outer core are both made of a Mn-Zn ferrite material, share a rotation axis, and overlap in a radial direction with a slight gap. The coil with the split core 1 of the outer core is the primary coil 5, and the coil with the inner core 3 is the secondary coil 7. The primary coil 5 is stored in the groove 14 on the inner surface of the split piece core 1, the secondary coil 7 is stored in the groove 13 on the surface of the inner core 3, and the lead wire of the secondary coil 7 is It is taken out through a groove 15 formed in the axial direction of the inner core 3.

In FIG. 1, the primary side coil 5 and the secondary side coil 7 are arranged to face each other on the same plane perpendicular to the rotation axis. In the non-contact type transformer shown in FIG. 1, three pairs of coils are formed on a pair of magnetic cores in the rotation axis direction. The primary coil 5 is on the power supply / transmission side, and the secondary coil 7 is on the power reception / reception side. Signals of three channels including power can be transmitted and received through three pairs of coils.

In the non-contact type transformer shown in FIG. 1, the split core 1 of the outer core covering the primary coil 5 has a cylindrical holder 9 (outer shape 7) made of non-magnetic plastic.
(0 mm, inner diameter 68 mm, height 60 mm). And the primary coil 5
Are fixed to the grooves 14 of each split piece core 1 with an adhesive. On the other hand, the inner core 3 applied to the secondary coil 7 has a cylindrical shape with an outer diameter of 56 mm, an inner diameter of 48 mm, and a height of 60 mm.

The transmission efficiency of the non-contact transformer according to the present embodiment was measured. One of the three coils was used for power transfer, and the other was used for signal transmission. Input is 12V / 15W
And the frequency by the function generator is 12
A 5 kHz sine wave input was used. As a result, according to the measurement using the spectrum analyzer, an output power of 7 W was obtained.

FIG. 3 is a diagram showing another embodiment of the non-contact type transformer according to the present invention. FIG. 3A is a plan view, and FIG. 3B is a side sectional view along AA. In FIG. 3, the primary side coil 6 and the secondary side coil 8 face each other in a pair in the direction of the rotation axis to form a non-contact type transformer. The primary coil 6 includes eight pieces with the split piece core 2 and is made of a nonmagnetic metal disk holder 10 (outer diameter 7
5 mm, an inner diameter of 48 mm, and a thickness of 3 mm) at an even angle and fixed. The primary coil 6 is configured by connecting eight coils in series. FIG. 4 shows the split core 2 with the primary coil 6. In the divided piece core 2 having a size of 20 × 10 × 3 mm,
Mn-Zn ferrite material is used. Each of the grooves 16 of the split piece core 2 forms an arc centered on the rotation axis.

FIG. 5 is a plan view of the core with the secondary coil 8. The secondary coil 8 has a donut shape (outside diameter 7
A pure iron core 17 having a size of 5 mm, an inner diameter of 48 mm, and a thickness of 3 mm) is formed on a holder 11 made of plastic or the like disposed on the surface.

Since it is not always easy to machine the circular groove 16, in practice, by appropriately setting the length of the split piece core 2 and the width of the groove 16 in which the primary coil 6 is formed, a straight line is formed. Groove. In the non-contact type transformer shown in FIG.
6 are formed concentrically or, in the case of a straight line, parallel to each other, and the primary side coils 6 are arranged corresponding to the respective grooves 16. By arranging a plurality of primary coils 6, a plurality of signals including electric power can be transmitted and received.

The transmission efficiency of the non-contact transformer according to the present embodiment was measured. One of the four coils was used for power transfer, and the other was used for signal transmission. Input is 12V / 15W
And the frequency by the function generator is 12
A 5 kHz sine wave input was used. As a result, it was measured with a spectrum analyzer, and an output power of 6 W was obtained.

FIG. 6
FIG. 4 is a diagram showing a part of a configuration variation in the non-contact transformer of the present invention. FIG. 6A is a diagram showing a non-contact transformer having a configuration in which the split piece core 2 is attached to the secondary side as well as the primary side. FIG. 6B shows that the secondary coil 8 is connected to a doughnut-shaped pure iron core 18 (outer diameter 75 m).
FIG. 3 is a diagram showing a non-contact transformer of a type stored in a circular groove 16 machined on a surface having a diameter of m, an inner diameter of 48 mm, and a thickness of 3 mm. FIG. 7 shows another split core 2 with a primary coil 6.
FIG.

According to the two embodiments, the mounting operation of the non-contact transformer of the present invention with respect to the power supply / reception unit in the wired electrical system is simplified by simply disposing a pair of cores facing each other. You can see that. Further, since the main body side and the handle side of the electric system of the automobile have a mechanically independent structure, the non-contact type transformer of the present invention eliminates sliding between wires and does not cause resistance when operating the handle, Has excellent durability and high reliability.

In contrast to the conventional non-contact type transformer using a large ferrite core, the non-contact transformer of the present invention uses a small ferrite core in combination.
There is no trouble of warping or deformation occurring during the sintering process, and it can be manufactured easily at low cost.

[0027]

As described above, according to the present invention,
An easy, inexpensive, and highly reliable non-contact type transformer can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of a non-contact type transformer according to the present invention. FIG. 1A is a plan view. FIG. 1B is a side sectional view.

FIG. 2 is a perspective view of a split piece core.

FIG. 3 is a diagram showing another embodiment of the non-contact type transformer according to the present invention. FIG. 3A is a plan view. FIG. 3B shows A-
The sectional side view which follows A.

FIG. 4 shows a split piece core with a primary side coil.

FIG. 5 is a plan view of a core with a secondary coil.

FIG. 6 is a diagram showing a part of a variety of configurations in the non-contact transformer of the present invention.

FIG. 7 shows another split core with a primary coil.

FIG. 8 is a schematic configuration diagram of a power supply / reception unit in a conventional wired electrical system.

FIG. 9 is a configuration diagram of an example of a known non-contact type transformer. FIG.
(A) is a plan view. FIG. 9B is a side sectional view.

[Explanation of symbols]

 Reference Signs List 1 split piece core (outer core) 2 split piece core 3 inner core 4 outer core 5, 6 primary coil 7, 8 secondary coil 9, 10, 11 holder 13, 14, 15, 16 groove 17, 18 pure iron Core 21 Flat cable 22 Mounting electrode

Claims (13)

[Claims] 1. A non-contact type electromagnetically coupled non-contact transformer in which coils forming a pair with a magnetic material core are closely opposed to each other on a circumference sharing a rotation axis,
Of the coils forming the pair, the magnetic material core applied to at least one of the coils is constituted by a plurality of split piece cores arranged so as to be an integer number of times rotationally symmetric about the rotational axis as the center of symmetry. Non-contact type transformer characterized by the following. 2. The non-contact type transformer according to claim 1, wherein the plurality of split piece cores are adjacent to other split piece cores with a finite space therebetween. 3. The non-contact type transformer according to claim 1, wherein the coils forming the pair are arranged to face each other on the same plane perpendicular to the rotation axis. 4. The plurality of split piece cores are arranged on a surface or an inner surface of a holder made of a non-magnetic material having a circular or regular polygonal cross-section and include the split piece core. The non-contact type transformer according to any one of claims 1 to 3, wherein the body core forms an inner core and an outer core in a direction perpendicular to the rotation axis. 5. The non-contact type transformer according to claim 1, wherein a plurality of pairs of the coils are formed in the rotation axis direction. 6. The magnetic core according to claim 1, wherein a groove is formed along a circumference around the rotation axis, and the coil is stored in the groove. Item 6. A non-contact type transformer according to any one of Items 5. 7. The magnetic core according to claim 1, wherein a groove having the same directional component as that of the rotation axis is formed, and the groove stores the lead wire of the coil.
A non-contact type transformer according to claim 5. 8. The coil according to claim 1, wherein the coils forming the pair are arranged on a circumference having the same diameter around the rotation axis and opposed in the direction of the rotation axis. The non-contact type transformer according to claim 2. 9. The magnetic core according to claim 1, wherein the magnetic core of at least one of the coils forming the pair is fixed on a plane. Non-contact type transformer. 10. The non-conductive coil according to claim 1, wherein a plurality of pairs of the coils are formed in a radial direction about the rotation axis. Contact type transformer. 11. The non-contact type transformer according to claim 1, wherein said coil is housed in a groove of said magnetic core. 12. The non-conductive coil according to claim 1, wherein the coil is formed in a circular or regular polygonal shape. Contact type transformer. 13. The non-contact type transformer according to claim 1, wherein the magnetic core is made of a soft magnetic ferrite or a metal magnetic material.