JPS61129715A - Ferrite head - Google Patents

Abstract

PURPOSE:To improve the reproducing efficiency and to reduce sliding noise by adhering a vibration absorbing body to at least a part of a peripheral surface of a ferrite head other than a tape sliding face. CONSTITUTION:A couple of head chips 1 are fixed incorporatedly via a gap 2 and a glass buried part 6 and the vibration absorbing body 7 is coated so as not to cover a winding slot 3 formed nearly at the center of the head chips 1. As the vibration absorbing body 7, a material such as rubber or synthetic resin is used. Since the vibration absorbing body 7 is coated to the upper face and both side faces of the head chips 1 other than the tape sliding face 1a, the elastic vibration of the head chips 1 caused by the tape sliding on the tape sliding face 1a is attenuated to reduce the sliding noise having correlation with the elastic vibration.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a recording/reproducing ferrite head used in a magnetic recording/reproducing device, and particularly to a ferrite head capable of reducing sliding noise.

[Technical Background of the Invention J A magnetic head installed in a video tape recorder (hereinafter referred to as V-rR) that records and reproduces images and audio, which is currently widely used, generally has a pair of magnetic heads as shown in FIG. The head dip 1 is integrally fixed via the gilt tab 2,
A winding wire 4 is wound through a winding FA groove 3 formed approximately in the center, and a head depth C is fixed to a head depth base 5.

Recently, digital V 1'R has been developed and has a frequency of several tens of MHz.
As it has come to be possible to record extremely high frequency signals, the f1 performance of magnetic heads has become more important than before. This is because the magnetic material tends to decrease as the frequency increases, and for this reason, ferrite, which has low eddy current and excellent wear resistance, is often used.

[Problems with blue technology] G) The ferrite used in the magnetic head in e) has a different effect and sliding noise depending on its composition and orientation. Currently, the sliding noise is not at its minimum at around 20,000 yen.1 This sliding noise is caused by the generation of elastic standing waves within the chip 1 due to the external force caused by the sliding between the tip and the head 1. ,
The cause is said to be that the internal magnetization of the head fluctuates due to the inverse magnetostrictive effect of the strain, and it is thought that this phenomenon is caused by the composition and orientation of the ferrite. Therefore, in order to reduce noise, there is a problem in that it is necessary to solve the problem by changing the composition even if it means reducing the regeneration efficiency a little.

``Object of the Invention'' The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a ferrite head that can improve reproduction efficiency and reduce sliding noise.

[Summary of the Invention 1 The present invention has a vibration absorber attached to at least a part of the outer peripheral surface other than the tape sliding surface of a ferrite head for recording and reproducing used in a magnetic recording and reproducing device1. According to the above, the elastic vibrations of the head chip are attenuated, improving reproduction efficiency and reducing sliding noise caused by sliding between the tape and the head chip.

Embodiment I of the Invention Hereinafter, an embodiment of the light head according to the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of the present invention.

As shown in Figure 4, parts that are the same or equivalent to the conventional example are designated by the same reference numerals. A pair of helad chips 1 and a gap 2 are integrally fixed through a lath embedded part 6, and the l/
A winding 11 formed approximately in the center of the head chip 1 is provided on the upper surface and both side surfaces of the head chip 1 provided with the head chip 1.
The vibration absorber 7 is coated so as not to cover the angle 43 degrees. The vibration absorber 7 may be formed by bonding a thin plate-like member, but it is easier to mass produce the vibration absorber 7 by coating the vibration absorber 7. The vibration absorber 7 C is made of a material such as rubber or synthetic resin. Further, it is desirable that the vibration absorber 7 is formed near the tape sliding surface 1a on the upper surface and both side surfaces of the head chip 1. Since the vibration absorber 7 is coated on the moving surface 1aLy, the outer top surface, and both sides, the tape will not touch the tape sliding surface 1aLy.
The elastic vibration of the head depth 1 generated by sliding on the head depth 1 is attenuated, and the sliding noise that is correlated with this elastic 1 movement can be reduced. In particular, if the vibration absorber 7 is coated near the sliding surface where stress from the tape is large, the above-mentioned effect will be even greater.

FIG. 2 is a perspective view showing another embodiment of the invention. +i
When recording and reproducing high frequency signals of several tens of MH1, such as in the digital V-R of RF IU, it is necessary to suppress the inductance without reducing the number of windings in order to sufficiently eliminate the output voltage. To this end, it has been proposed to reduce the cross-sectional area of the head winding so as not to reduce the inductance per turn. The head chip 1 made by this method is the second
As shown in the figure, the length of the sliding surface 1a is shortened. This structure has the problem that the rigidity of the tip of the head chip 1 is reduced, and even with the same stress, large distortion occurs, resulting in sliding noise at corners. In this prefectural assembly, the same effect as in (previous)) can be achieved by coating the side surfaces of the tip of the head chip 1, excluding the tape sliding surface 1a, with a vibration absorber 7 as shown in Figure 2. In this embodiment, the upper surface of the head chip 1 may also be coated with the vibration absorber 7.

FIG. 3 shows measured data showing the difference in the amplitude of 1-g dynamic noise between when the head chip 1 having the structure shown in FIG. 2 is coated with the noise absorber 7 and when it is not coated. It is. Curve C in the figure is the system noise when the tape is not sliding, curve a L;・Noise level θ tram 1 and 01 measured by applying vibration absorption 1 tree 7 to module 1.

As shown in Fig. 3, as is clear from the 11q deck, by applying vibration absorption (A7) to the outer circumferential surface of the l\tud chip other than the tape sliding surface,
oMl-1zL! This is possible by reducing the above (-J dynamic noise).This allows the composition and orientation of the ferrite head to be selected to improve the 11'B bioefficiency, and also achieves noise reduction.

In the above-described embodiment, the vibration absorber 7 is provided on one side and three sides of the head chip 1, but the vibration absorber 7 may be provided on four sides including the bottom surface of the head chip 1.

[Effects of the Invention] As described above, according to the present invention, at least a portion of the outer circumferential surface other than the sliding surface of the ferrite head of a magnetic recording/reproducing device such as a V'TR is Since a vibration absorber is provided on the head, it is possible to improve the regeneration efficiency of the light head and reduce the sliding noise.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of a ferrite head according to the present invention, FIG. 2 is a perspective view showing another embodiment of the present invention,
FIG. 3 is a graph showing the relationship between the 77 frequency and sliding noise, which is not shown in FIG. 2 but was actually measured in an example, and FIG. 4 is a perspective view C showing a conventional ferrite head. 1... Head chip 1 total... Table sliding surface 7...
・1 commotion absorber

Claims (3)

[Claims] (1) A ferrite head for recording and reproduction, characterized in that a vibration absorber is attached to at least a part of the outer peripheral surface of the ferrite head other than the tape sliding surface. (2) The ferrite head according to claim 1, wherein the vibration absorber is made of rubber. (3) The ferrite head according to claim 1, wherein the vibration absorber is made of synthetic resin.