JPS60111306A - Magnetic head - Google Patents

Abstract

PURPOSE:To decrease generation of noise by adding a carbon black or graphite to a forming material formed incorporatedly with a case main body constituting an erase head and a tape slide face of a head and bringing the area resistance value of the said forming material to a specific range so as to decrease the charge of the tape slide face and smooth the tape running. CONSTITUTION:The antistatic additives such as carbon black or graphite is added properly to the basic constituting material of the case main body 10 formed incorporatedly with the tape slide face in addition to a plastics (e.g., nylon, polyphenylene sulfide or polybutylene telephthalate or the like), an inorganic filler (e.g., alumina, calcium carbonate or quartz glass) and glass fiber and the static electricity due to friction at tape running is prevented with the area resistance value of 10<10>-10<13>[OMEGA/cm<2>]. The weight ratio of the constituting material, plastics, inorganic filler, glass fiber and carbon black or graphite is 35:65:8:1 as an example.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an erase head for audio signals such as a V-TR, and a case body constituting the erase head; , as shown in FIG.
0/The fitting part 2 is inserted from the back side into the case body 2 into which the head part 1 consisting of a bank core and a bank core is installed.
a is formed and the tip of the front core 1a of the head portion 1 is accurately positioned on the tape sliding surface 2b of the case body 2. A front block 3 made of material is integrally buried, and after incorporating the head part 1 and applying internal molding, the tape sliding contact surface 2b is
'4 A magnetic head as shown in FIG. 2 was manufactured by polishing it into a predetermined arc shape.

However, since the molding material of the front block 3 does not contain any antistatic agent or the like as a measure to prevent static electricity, it has high insulating properties, and the magnetic tape and
Friction with the tape sliding surface generates static electricity, which deteriorates tape running and causes noise. In particular, the higher the insulating properties of the molding material for the front block 3, the greater the charge amount, and the larger the sheet resistance value [4.y,], and when the charge amount reaches a certain value or more, There were drawbacks such as increased noise due to discharge.

<Means for Solving All Problems> The present invention has been made in order to solve the above-mentioned conventional drawbacks, and as a measure to prevent static electricity from forming on the tape sliding surface of the magnetic head. Carbon black or graphite is added to the molding material used to integrally mold the case body and the tape sliding surface of the head part, and the sheet resistance value of the molding material is set to 1010 to 10"'C4".
The present invention provides a magnetic head with a diameter of J.

<Embodiments of the Invention> Hereinafter, embodiments of the present invention will be described based on FIG. 3. In the figure, 10 is a case body molded integrally with the tape sliding surface, 11 is a front core of a head portion, 12 is a gap, and 13 is a molded resin.

The basic constituent materials of the case body 10, which is molded integrally with the tape sliding surface, are plastics (for example, nylon, polyphenylene sulfide, polybutylene terephthalate, etc.), inorganic fillers (for example, alumina, calcium carbonate, quartz glass), and glass fibers. In addition, an appropriate amount of antistatic agent such as carbon black or graphite is added, and the area resistance value w1. 'olO～i o't (%]
This prevents static electricity caused by friction when the tape runs.

Here, the weight ratio of plastics, Me-free filler, glass fiber, carbon black, or graphite of the basic constituent materials is 35:65:8:15 as an example, and a good charging effect can be obtained. ing.

In addition, if the inorganic filler in the basic constituent materials is too small, problems will arise in the abrasion resistance during tape running, so it is desirable to have a plastic/inorganic filler weight ratio of 3-5 or less. be.

Additionally, glass fiber is an additive used to improve the transverse strength of the material.

On the other hand, carbon black, which is added as a measure to prevent static electricity, is finely divided carbon obtained by incomplete combustion or thermal decomposition of natural gas, petroleum, etc.

<Operation and Effect> As explained in detail above, in the magnetic head according to the present invention, the case body constituting the erasing head and the tape sliding surface of the head portion are made of plastic, inorganic filler, glass fiber, carbon black, or graphite. The basic constituent materials such as
It has the following effects: the amount of charge on the tape sliding surface is small, the tape runs smoothly, noise generation is reduced, and the performance as an erasing head can be improved. play.

[Brief explanation of the drawing]

1 and 2 are exploded structural views of a magnetic head showing a conventional embodiment and a perspective view after assembly is completed, and FIG. 3 is a perspective view of a magnetic head according to the present invention. 10...Case body, 11...Head part, 12...
・Gap, 13...Mold resin. Patent applicant: TDC Co., Ltd. Agent: Hideaki Tosa, patent attorney

Claims (1)

[Claims] In an erasing head using a molded object as a sliding surface, carbon black or graphite is added to the molding material formed by integrally molding the case body and the tape sliding surface constituting the erasing head as an antistatic agent to prevent static electricity. At the same time, the sheet resistance value of the molding material is increased from 1010 to io”
'C%).