JPH0157409B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic transducer such as a magnetic sensor or a magnetic head, and a method for manufacturing the same.

Conventional magnetic heads and magnetic sensors are comprised of a ring-shaped or other shaped core having a magnetic gap made of magnetic metal or magnetic ferrite, and a conductor coil wound around a portion of the core. This method separates the core manufacturing and winding operations, resulting in inconsistent results, and the winding process is time consuming.
Additionally, in general, it is inconvenient to attach the coil unless the magnetic core is divided into two parts.

An object of the present invention is to provide an electromagnetic transducer based on a completely new idea, which is different from conventional magnetic heads or magnetic sensors, and a method for manufacturing the same. That is, the present invention is characterized in that both the magnetic core and the windings are composed of film-like layers, making them thin and compact elements, and the magnetic cores and the windings are all formed using printed lamination technology or other thin film technology. Technology (sputtering, ion plating, etc.)
It is characterized by being manufactured in a consistent process using

Thin magnetic heads are useful, for example, as video heads or digital detectors.
The electromagnetic conversion element of the present invention is easy to manufacture,
Application of printing technology has advantages such as the ability to manufacture a large number of devices at the same time.

The invention will be explained in detail below in conjunction with the drawings.
1 to 4 are plan views showing a method of manufacturing an electromagnetic transducer according to an embodiment of the present invention.
As shown in FIG. 1, a magnetic layer 1 is first printed on a suitable flat plastic film (not shown). As the magnetic material, a magnetic paste made by kneading high μ ferrite powder with a suitable binder is used. Actually, printing of the magnetic layer 1 is carried out simultaneously on the surface of the plastic film 2 in large numbers as shown in FIG. 5, and the steps shown in FIG. 2 and subsequent steps are the same. The magnetic layer 1 is depicted as having an inverted U-shape, with both legs separated widely to form a magnetic gap 3, but this is for convenience of drawing, and in reality the legs are very close together. It's normal. If the thickness of the magnetic layer 1 is too thin, mechanical strength cannot be achieved, and if it is too thick, the difference in level becomes large, so that the thin film conductors on the front and back sides can be connected through the through holes (punch holes) described below only by printing conductive paste. I can't do that. Therefore, about
It should be between 20 μm and about 40 μm thick.

The magnetic layer 1 is dried, and then two rows of through holes 4 arranged in a staggered relationship as shown in FIG. 2 are punched. Since the magnetic layer 1 is supported by a plastic film as shown in FIG. 5, the through holes may penetrate up to the plastic film.

Moving on to the process shown in FIG. 3, conductors 5 are printed in parallel so as to connect the upper and lower two rows of through holes, and lead-out conductors A are printed toward the edges. The conductor is, for example, Pd,
A conductive paste made by kneading heat-resistant metal powder such as Pd-Ag with a suitable binder is used. Once the conductor is dry, the magnetic layer 1 is peeled off from the plastic film and supported upside down on another flat plastic film, or alternatively it is positioned with a suitable ruler on the article feeding means of a printing press. In the former case, in order not to disturb the mutual relationship of the magnetic layers, for example, a flat plastic film containing an adhesive may be superimposed and pressed onto the printed material that has undergone the steps up to FIG. 3 to transfer the material. Use.

Next, as shown in FIG. 4, the same conductive paste used in FIG. , and also print leader line B. In this way, a coil that goes around one side of the magnetic layer 1 through the through hole 4 is formed.
After the conductor 6 is dried, each laminate is placed in a firing furnace and fired at an appropriate temperature to sinter the magnetic layer 1 and firmly bond the conductors 5, 6, A, and B to the magnetic layer 1.

FIG. 6 shows an equivalent view of the completed magnetic head, and FIG. 7 shows an example of its application, illustrating its use as an angle sensor of the rotating shaft. Reference numeral 7 denotes magnets magnetized at regular intervals, which are attached to the rotating shaft, and the magnetic sensor 8 of the present invention is provided opposite to these magnets.

Although the example shown above is the simplest example, various variations are possible.

First, in the examples shown in FIGS. 1 to 7, the conductors 5, 6, A, and B were printed on the magnetic layer 1 and then fired. However, in this case, a heat-resistant metal powder must be used as the conductive paste. Therefore,
After completing the steps shown in FIG. 2, firing may be performed first, and then the fired magnetic layers 1 may be sent one by one to a printing machine using a suitable jig to print the conductive paste. This conductive paste may contain powders of silver, copper, etc., for example.

Alternatively, plastic film 2 (5th
A raw magnetic sheet is used instead of the one shown in Fig. 2, on which through-holes similar to those shown in Fig. 2 are directly formed, and conductors A, B, 5, and 6 similar to those shown in Figs. 3 and 4 are printed. Next, it may be punched into a U-shaped outer shape using a punch die, and then fired.

Although the magnetic layer 1 is only one layer, it can be made into two layers, three layers, etc. depending on the purpose. For example, in the example shown in FIGS. 1-7, magnetic layers may be further printed on the front and back sides of the laminated print body.

8-11 show a method of manufacturing an electromagnetic transducer according to the present invention. As shown in FIG. 8, a magnetic layer 11 is printed on the plastic base 10 in the form of a square (or any shape such as a rectangle) with no voids, and then a punch similar to that described in connection with FIG. Holes (not shown) are formed and then conductors 12 similar to those described in connection with FIG. 3 are printed. Once this step is completed, the plastic base is cut along the chain lines of FIG. 8 to obtain a strip as shown in FIG. Next, a void portion 13 is formed using a cutting die. The magnetic layer 11 is transferred to another plastic base 14 (FIG. 11) in the same manner as in connection with FIG. 4, and the base film 10 is peeled off. Next, the conductor 15 is printed so as to be connected to the lower conductor 12 through the punched hole to form a conductor coil that goes around the upper side of the magnetic layer 11 (corresponding to FIG. 4). After this step is completed, the laminate is peeled off from the film base 14 and fired at the required temperature and time, and finally, appropriate external terminals are fired at the ends of the conductors 12 and 15 to complete the electromagnetic transducer element. This embodiment has the advantage that the magnetic gap can be formed more precisely than by printing.

The punching process for the gap 13 and the process for cutting the film in the embodiment just described may be reversed. That is, after the process shown in FIG. 8 is completed, the void 13
It may be formed by punching and then cut along the chain lines.

In all the embodiments described above, it is also possible to fill the voids with ceramic or glass by a printing method in order to protect the voids. For example, a paste containing alumina or glass powder is prepared and this paste is printed into the void 3 after the step shown in FIG. 1, or the paste is printed into the void 13 before or after the step shown in FIG.
A method such as printing Heko paste can be adopted. Such a ceramic or glass layer can protect the air gap and reduce clogging and wear when the transducer element of the invention contacts magnetic tape or the like.

As is clear from the above description, the electromagnetic transducer of the present invention is of a membrane type and can be made small. Nevertheless, it is easy to manufacture and mass production is possible. Further, according to the present invention, there is no need for complicated winding. As described above, the present invention employs technical means completely different from those of conventional magnetic heads.
We were able to obtain excellent effects.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the first step in manufacturing the electric/magnetic conversion element of the present invention, FIG. 2 is a plan view showing the second step, FIG. 3 is a plan view showing the third step, and FIG. Fig. 4 is a plan view showing the final process, Fig. 5 is a plan view showing the allocation during mass production, Fig. 6 is a plan view of the completed device, Fig. 7 is a front view showing the state of use, and Fig. 8 to FIG. 11 are plan views showing each sequential process of a manufacturing method according to another embodiment of the present invention. The main parts in the figure are as follows. 1, 11: magnetic layer, 3, 13: magnetic gap,
4: Through hole, 5, 6, 12, 15: Conductor, A,
B: Drawer conductor.

Claims (1)

[Scope of Claims] 1. Ferrite magnetic films that are approximately U-shaped and whose ends face each other across a narrow magnetic air space, which are arranged at approximately regular intervals along a portion of the U-shape. an insulating and magnetically permeable ferrite magnetic film having two rows of through holes staggered with each other; An electromagnetic conversion element comprising a plurality of parallel thin film conductors that extend from a through hole in one row to a through hole in another row and are electrically connected on the front and back sides by the through holes. 2. Print a magnetic paste made by pasting insulating and magnetically permeable ferrite powder to form a nearly U-shaped magnetic layer with narrow ends facing each other across a magnetic air space. Two rows of punched holes arranged at approximately constant intervals along a part of the U-shape and staggered with each other are formed in the magnetic layer, and the ferrite magnetic layer is formed so as to form a coil circulating through the punched holes. A plurality of parallel thin film conductors extending from the punch holes in one row to the punch holes in the other row are printed on the front and back surfaces of the membrane to form a conductor coil, and then sintered. A method for manufacturing an electromagnetic conversion element.