JPS6291003A - Non-reversible transmission element - Google Patents

Abstract

PURPOSE:To obtain the titled element having simple and small-sized structure and to attain fine adjustment of a magnetic field by fitting a magnetic plate having a larger diameter than that of a magnet to a face opposite to a ferrite element of the magnet. CONSTITUTION:The magnet flux 33 perpendicular to the plate within the outer diameter range of the magnet 20 coming from the plate face 29a of the magnetic plate 29 among the magnetic flux of the magnet 20 is effective parallel magnetic flux and gives a magnetic field to ferrite element 18, 19. The magnetic plate circumferences 29b causing leakage magnetic flux is cut off partially shown in hatched lines to adjust the entire magnetic field fed to the ferrite element optionally from the magnet 20 via the magnetic plate 29. Thus, the tolerance of the outer diameter of the magnet is relaxed to some degree, the manufacture and assembling of the non-reversing transmission element are facilitated and a screw type adjusting mechanism required for a conventional element is not required.

Description

Detailed Description of the Invention (Industrial Application Vf) The present invention relates to a non-reciprocal transmission element such as an isolator or a circulator, and particularly relates to a non-reciprocal transmission element such as an isolator or a circulator, and in particular a non-reciprocal transmission element having a function of adjusting a magnetic field applied to a ferrite element housed in a case. Regarding transmission elements.

(Prior art) A pair of ferrite elements are disposed close to each other and facing each other in a case, and a permanent magnet is placed on one side of the pair of combined 7-elite elements to apply a magnetic field to the ferrite element. In isolators and circulators in which lead wires are drawn from a pair of ferrite elements to the input/output terminals of a case, in order to change the strength of the magnetic field applied to the ferrite elements, a magnet is conventionally held in an adjustable position. It has been proposed to adjust the magnetic field by changing the spacing between the magnet and ferrite elements.

FIG. 4 is a schematic vertical sectional view of a conventional isolator with a magnetic field adjustment mechanism. A pair of ferrite elements 18, 19 are mounted inside the case 21 facing each other, and lead wires 26, 27 are drawn out from each ferrite element and connected to input/output terminals of the case. An adjustment screw 30 is screwed into the case 21 at a position facing the ferrite element, and the ferrite element is attached to the tip of the adjustment screw 30.
, 19 is fixed to a magnet 31 that applies a quiet magnetic field, and an adjustment screw 30 is operated from outside the case to change the distance between the magnet 31 and the ferrite element to adjust the magnetic field applied to the ferrite element.

(Problems to be Solved by the Invention) Although the above-mentioned conventional screw type adjustment structure has the advantage that the adjustment screw can be adjusted from the outside with a simple tool after assembly, the structure is complicated and the shape is small. It is larger and requires more parts, and the adjustment range is limited by changing the position of the magnet only by adjusting the screws, making it difficult to accurately and sufficiently adjust the magnetic field.
The drawback was that fine adjustment was not possible. Furthermore, since the magnet is held by a screw mechanism, the position of the magnet is uncertain, making it difficult to obtain stable performance. In addition, with the magnet B-fixing type, it is very difficult to adjust the magnetic field during assembly.

(Means for Solving the Problems) The present invention provides a non-contact device in which a pair of ferrite elements are arranged in a case, and a magnetic field is applied to the ferrite elements by a magnet arranged opposite to the ferrite elements. In the reversible transmission element, a dimagnetic root having a larger diameter and better rigidity than the magnet is fixed to the facing surface of the one magnet ferrite element, and a corner of the magnetic plate is shaved off to adjust leakage magnetic flux from the magnetic plate. It was designed to do so.

(Example) Next, the present invention will be described with reference to the drawings.

FIG. 1 is a schematic vertical cross-sectional view of a non-reciprocal transmission element according to an embodiment of the present invention. Furthermore, FIG. 2 is a side view of a magnetic plate and a magnet showing a state in which the magnetic field of the magnet is adjusted in the irreversible transmission element according to the present invention, and FIG. 3 is an end view of the magnet according to the present invention as seen from the magnetic plate side. It is. A pair of ferrite elements 18, 19 are arranged and fixed in the case 11 facing each other with a slight interval, and a pair of lead wires 26 are connected from the opposing surfaces of each ferrite element 18, 19.
．． 27 is pulled out, and the input/output terminal 17.2 of the case 11
8 and also within the case is a magnet 20 for applying a magnetic field to these ferrite elements 18, 19.
The arrangement is the same as in the conventional example explained in FIG. However, in the present invention, as shown in FIG.
A magnetic plate 29 (outer diameter D) having a larger diameter than the outside diameter d of the magnet is fixed to the end face of the magnet, that is, the face facing the ferrite element. The magnetic plate 29 is fixed approximately concentrically to the center of the magnet 20, so that the magnetic plate 29 protrudes outward from the outer periphery of the magnet 20.

As shown in FIG. 2, the magnetic flux generated by the magnet 20 is generated by spreading from the plate surface 29a of the magnetic plate 29 to the peripheral portion 29bVc of the magnetic plate. Of these, the plate surface 29 of the magnetic plate 29
The magnetic flux 33 that is perpendicular to the plate surface and that corresponds to the outer diameter range of the magnet 20, which comes out from the point a, becomes a parallel effective magnetic flux and provides a magnetic field to the ferrite elements 18 and 19 (FIG. 1). The magnetic flux 34 emitted from the vicinity of the periphery of the magnetic plate 290 spreads radially, and part of it is applied to the ferrite element, but the other part does not become an effective magnetic flux to the ferrite element, and becomes so-called leakage flux. By partially scraping off the magnetic plate peripheral part 29b where this leakage magnetic flux occurs, as shown in the shaded area in the figure, the entire magnetic field applied from the magnet 20 to the ferrite element via the magnetic plate 29 can be adjusted as desired. can do. As shown in the shaded area in Fig. 2, the magnetic plate 29
The range and strength of the effective magnetic flux 33 emitted from the surface of the magnetic plate 29 can be changed by cutting off the entire 0th circumference, or by cutting out a part 35 of the ridge of the magnetic plate 29 as shown in FIG. Adjust the strength of the magnetic flux generated from the part.

Due to the material of the magnet, it is extremely difficult to remove part of it by pirates, but the magnetic plate is made of permalloy, which has high magnetic permeability, and is easier to cut than lucotoni, and when assembled, it is difficult to remove a part of the ferrite element. 18.19 Adjust the magnetic field by cutting off a part of the magnetic plate 29 to determine the range and strength of the required magnetic flux while measuring the magnetic field.
conduct.

(Effects of the Invention) As explained above, according to the present invention, the magnetic flux applied to the ferrite element of the irreversible transmission element can be adjusted arbitrarily by partially scraping off the magnetic plate. The dimensions can be made somewhat rough, making it easier to manufacture and assemble the irreversible transmission element. There is no need for a conventional screw type adjustment mechanism, the structure is simple and compact, and a non-reciprocal transmission element that allows fine adjustment of the magnetic field and is stable and has good performance can be obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view of a non-reciprocal transmission element according to an embodiment of the present invention, FIG. Figure 3 is an end view of the magnet according to the present invention as seen from the magnetic plate side;
FIG. 4 is a longitudinal sectional view of a non-reciprocal transmission element equipped with a conventional magnetic field adjustment mechanism. 11...Case, 20...Magnet. 18.19... Ferrite element, 17.28... Input/output terminal, 29... Magnetic plate, 33... Effective magnetic flux, 3
4...Leakage magnetic flux.

Claims (1)

[Claims] In an irreversible transmission element in which a pair of ferrite elements are disposed in a case and a magnetic field is applied to the ferrite elements by a magnet disposed opposite to the ferrite elements, a surface of the magnet facing the ferrite element has a larger area than the magnet. An irreversible transmission element characterized by a large-diameter magnetic plate fixed to it.