JPH04109408A - Magnetic head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multi-channel magnetic head necessary for high-speed magnetic recording on a recording medium on a drum surface such as a magnetic printing device.

[Prior Art] Magnetic recording is used to form a magnetic latent image in a magnetic printing device, and the device is composed of a magnetic head and a recording medium. As the magnetic head, a multi-channel in-plane magnetization type magnetic head or a multi-channel perpendicular magnetization type magnetic head is used. The resolution of magnetic recording determines the resolution of printing; for example, to obtain a resolution of 300DPI, 25.4mm is required.
It is necessary to form a magnetized region of ÷300=0.085 mm/dot. 0. on the short side 210mm of A4 size paper.
When forming a magnetized area of 085 mm, 210÷0
．． Since 085=2470 dots are required, it is important to perform magnetic recording at high speed. In the case of a magnetic head other than a full channel magnetic head, it is necessary to scan the magnetic head, and the printing speed cannot be improved unless the scanning speed is increased as the number of channels decreases. In the case of linear motion, there is a limit to the scanning speed due to constraints from acceleration and deceleration, and in order to increase the printing speed, it is desirable to have a magnetic head with as many channels as possible. However, multi-channel magnetic heads require highly precise machining, making it difficult to manufacture them at low cost.

Also, if there is magnetic interaction between adjacent magnetic poles, when writing with the magnetic pole of a certain channel, the magnetic flux generated in that coil will flow not only to the yoke but also to the adjacent magnetic pole, disturbing the magnetization state. become.

[Problems to be Solved by the Invention] The present invention has been made in view of these problems, and includes:
The purpose is to provide a multi-channel magnetic head that is inexpensive, has high precision, and has little magnetic interaction between channels.

[Means for Solving the Problems] In order to uniformly form a magnetized region of about 0.085 mm as described above, the dimensions of the magnetic pole tips must be precisely machined and precisely arranged. In addition, in order to reduce magnetic interaction between channels, by arranging the distance between adjacent magnetic poles to be greater than the distance between the magnetic poles and the yoke, the magnetic flux generated from the coil can be reduced by '6! It becomes possible for most of it to flow to the yoke via the i-pole.

Structurally, linear magnetic poles are inserted into a cylindrical (vibe-shaped) main magnetic pole that can easily obtain high dimensional accuracy and can be manufactured at low cost, and the yoke is attached by fixing the linear magnetic poles in holes corresponding to the number of channels. Cylindrical coils corresponding to the number of channels are attached to the magnetic pole, and filled with a non-magnetic filler. It is desirable for the magnetic material of the magnetic poles and yokes to have high magnetic permeability and magnetic flux density, and low coercive force and electric conductivity. Further, when coming into contact with a recording medium, wear resistance is required.

By providing the main pole with a lateral protruding end or by providing a guide plate to improve the positional accuracy of the tip of the magnetic pole, assembly becomes easier and an inexpensive magnetic head becomes possible.

[Example] Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1(a) is a perspective view of the entire magnetic head, and FIG. 1(b) is a sectional view thereof. A magnetic pole 4 is inserted into a cylindrical main magnetic pole 3, and these are fixed to a yoke l. A cylindrical coil 2 is attached to the magnetic pole and filled with a non-magnetic filler. Ultimately, good magnetic and mechanical properties can be obtained by polishing to match the shape of the drum. The yoke 1 serves both as a magnetic return bus and as a structural support.

Also, the distance Y between adjacent magnetic poles 4 is the distance I between the magnetic poles 4 and the yoke 1! If the magnetic flux is smaller than Z, the magnetic flux is
A magnetic interaction occurs between the two.

Therefore, they are arranged so that the relationship between the dimensions Y and Z is Y>Z.

FIG. 2 shows a cross-sectional view of an embodiment of the main pole 3'.

The tip of the main magnetic pole 3' is widened and a laterally protruding end is provided.
This facilitates fixation to the yoke 1.

FIG. 3 shows a sectional view of an embodiment in which the magnetic pole 4 is inserted into the positioning hole of the guide plate 6. Accurately determining the position of the tip of the magnetic pole 4 is difficult without using a jig or the like, but it is possible by providing a guide plate.

[Effects of the Invention] As described above, according to the present invention, the magnetic flux generated by the coil passes through the main magnetic pole and the magnetic pole, via the recording medium, and returns via the yoke to form a magnetic circuit. At this time, in the recording medium, a magnetized region is formed near the magnetic pole along the flow of magnetic flux. Because of the yoke, magnetic interaction between adjacent magnetic poles is extremely low. Furthermore, each component has a shape that is easy to manufacture, and assembly is easy, making it possible to produce an inexpensive multi-channel magnetic head.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the entire structure and cross section of the present invention, Figure 2 is a diagram showing a case in which the tip of the main magnetic pole is processed to facilitate assembly, and Figure 3 is a diagram showing a case in which a guide plate for positioning the magnetic pole is attached. This is a ward that indicates the case. 1... Yoke, 2... Coil, 3... Main magnetic pole, 3
“...Main magnetic pole, 4...Magnetic pole, 5...Non-magnetic filling moon, 6...Guide plate. Applicant: Seiko Epson Corporation, Patent Attorney, Kizobe Suzuki, and 1 other person ×-X large mouth)

Claims (4)

[Claims] (1) A magnetic head having a plurality of magnetic poles, a coil, and an integrated yoke, and characterized in that the distance between adjacent magnetic poles is greater than the distance between the magnetic poles and the yoke. (2) In a multi-channel magnetic head, a linear magnetic pole is inserted into the tip of the cylindrical main pole, this is fixed to the yoke to form a magnetic circuit equal to the number of channels, and a cylindrical coil is attached to the magnetic pole. A magnetic head characterized by being filled with a non-magnetic filler material. (3) The magnetic head according to claim (2), characterized in that a laterally projecting end portion is provided at the tip of the main pole. (4) The magnetic head according to claim (2), wherein the magnetic pole tip is arranged in a positioning hole of the guide plate.