Magnetic core

The present invention refers to a magnetic core comprising flat magnetic plates superimposed and joined in order to constitute the toroidal form of the core, creating an internal space for the winding and a lateral air gap groove. There being assembled in the open space of the core or air gap, annulling it, an open hoop made of magnetic material having suitable dimensions, whose outer edge penetrates into the interior space of the winding in order thus to create a new internal air gap because the external diameter of the hoop is smaller than the internal diameter of the space available for the inductance coils. In this way a magnetic shunt is situated between the inductance coils in order to regulate their mutual inductance.

SUMMARY OF THE INVENTION 
The present invention contemplates improvements in the construction of 
magnetic cores for electric inductance apparatus, which represents a novel 
and substantial advancement over the present state of the art. 
The improvements that are the subject of the present invention have been 
studied and developed with complete success in order to make it possible 
to house two or more induction coils in toroidal magnetic cores and to 
place a magnetic shunt between them in order to regulate the mutual 
inductance, thus improving the working conditions of the reactances. 
These improvements are based on the construction of a toroidal core formed 
by flat plates duly assembled in order to form the annular core 
constituting an internal rectangular space for housing the induction coil, 
as well as an open space in one of the branches of the core in order to 
provide the corresponding and necessary air gap in which is placed an 
incomplete hoop of magnetic material situated in the centre of the space. 
The coil is housed, in such a way that the external main air gap is 
annulled in order to create a new internal air gap, making it possible to 
house at least two coils situating between them the magnetic shunt which 
regulates their mutual inductance. 
The invention is described in the following description by reference to the 
accompanying drawings which show by way of example a preferred embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION 
Referring to the drawings; and more particularly to FIG. 1, the magnetic 
toroidal core in accordance with the invention is constituted by a number 
of flat plates (1), preferably in the shape of a J in such a way that by 
joining the longer ends of a suitable number of plates a toroidal form is 
created, owing to the double thickness formed by the joined ends or 
branches, while the shorter bent branches (2) form a single thickness, 
leaving a free space between the ends of the shorter branches (2) in the 
form of a primary air gap. 
It is pointed out that, for the purposes of the present invention, the 
toroidal magnetic core may be obtained with other types of flat plates, 
duly combined for the purpose, since the basic concept of the present 
invention contemplates a suitable dimensioned open hoop (4) of magnetic 
material (FIG. 3) placed in the air gap between the smaller branches (2) 
and the primary air gap produced on forming the core, and therefore 
annulling it. As illustrated in FIGS. 1 and 2, the outer edge (6) of the 
hoop penetrates up to the mid-zone of the internal space which houses the 
induction coils (3), in order to create a new internal air gap (5) because 
the external diameter of the hoop is smaller than the internal diameter of 
the space available. 
In this way it is possible to house at least two coils (3) in the interior 
of the toroidal core situating between them a magnetic shunt created by 
the hoop (4) in order to regulate their mutal inductance.