JPS61222014A - Method for measuring electromagnetic conversion characteristic of rotary magnetic head - Google Patents

Abstract

PURPOSE:To measure efficiently an electromagnetic converting characteristic by fixing a rotary magnetic head to the fitting part of a measurement device whose position is adjusted, winding fixedly a magnetic tape to the circumferential slot of a rotary drum and adjusting the position of the rotary magnetic head while observing the contact state between the magnetic tape and the rotary magnetic head. CONSTITUTION:The rotary magnetic head 2A is fixed to the fitting part 6 of a measuring device 5 whose position is adjustable, while the magnetic tape 10 is wound fixedly to the circumferential slot 11 of a rotary drum 9, the rotary magnetic head 2A is contacted with the peripheral face of the tape 10 properly while the drum 9 is being turned to measure the characteristic of electromagnetic conversion. Thus, the position of the rotary magnetic head 2A is adjusted while the contact state between the magnetic tape 10 and the rotary magnetic head 2A is observed directly by a display device, and the head 2A and the measuring device 5 are connected directly via a cord to improve the measuring efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for measuring electromagnetic conversion characteristics of a rotating magnetic head for recording and reproducing video signals used in video tape recorders and the like.

Conventionally, when measuring the electromagnetic conversion characteristics of a rotating magnetic head for a VTR, a rotating magnetic head 2 is attached to an appropriate location on a rotating cylinder or rotating drum 1 using a fixture, as in an actual video tape recorder, as shown in Fig. 1. , on the other hand, the magnetic tape 3 is provided outside the rotating drum 1 via a plurality of rotating rollers 4.4 so as to form a semi-circular running path facing the rotating drum, and the magnetic tape 3 moves in the direction of the arrow. A rotary drum 1 (not shown) performs recording and reproduction on a magnetic tape 3 while rotating the rotary drum 1 at high speed relative to the tape 3.
This was done through a rotating transformer that rotated with the

Therefore, the conventional method described above has the following drawbacks.

(2) It is not possible to immediately check (II adjustment) while observing the contact state between the magnetic tape and the rotating magnetic head.

In other words, if the contact between the two is poor, the rotating drum 1, which is rotating at high speed, should be stopped again, and the rotating magnetic head 2 should be removed from the fixture while adjusting the position before installing the rotating magnetic head 2. , the contact status between the two must be reconfirmed.

Therefore, this method was extremely inefficient in measuring work.

(2) Since the rotating magnetic head 2 rotates together with the rotating drum 1, an intermediary for extracting electrical signals is required, such as a rotating transformer for transmitting the electrical signals from the rotating magnetic head to the measuring equipment.

Therefore, the overall structure of the measuring device has become complicated, and the cost has also increased.

(2) Because the magnetic tape 3 ran so as to cover the rotating magnetic head 2, it was not possible to sufficiently measure the electromagnetic conversion characteristics of the rotating magnetic head.

In view of the above-mentioned drawbacks of the conventional art, the present invention enables the position of the rotating magnetic head to be easily adjusted while directly observing the value of the contact state between the magnetic tape and the rotating magnetic disk. A method for measuring the electromagnetic conversion characteristics of a rotating magnetic head, which allows the entire measuring device to have a simple configuration without providing an intermediary, and also allows the electromagnetic conversion characteristics of the rotating magnetic head to be sufficiently and efficiently measured. is to obtain.

Hereinafter, the present invention will be explained in detail with reference to an embodiment shown in the drawings.

In the embodiments shown in FIGS. 2 to 4, A indicates an example of an electromagnetic conversion characteristic measuring device for a rotating magnetic head used in the measuring method of the present invention. That is, reference numeral 5 denotes a position-adjustable electromagnetic conversion characteristic measuring device, and one side wall of the measuring device 5 is provided with a protruding mounting portion 6 that can fix the rotating magnetic head 2A in a horizontal state. When fixing the rotating magnetic head 2A to the mounting portion 6, an appropriate fixing device may be used, but it is necessary to secure the fixed end or the mounting end of the rotating magnetic head 2A to the mounting portion 6 so that it can be inserted and removed freely. A matching groove may be formed. Further, the measuring device 5 is a second
As shown in the figure, there is a measuring device 5a having terminals for connecting various cords to be connected to a value display, etc., and a rotary magnetic head 2A which is provided integrally with this measuring device 5a and can move up and down the position. A vertical movement device section 5b, a rotating disk 5C provided below the vertical movement device section 5b and capable of rotating the rotating magnetic head 2A in the circumferential direction of arrow B shown in FIG. 3, and a rotating magnetic head. 2A position also 3rd
It is composed of a movable substrate 5d that can be adjusted in the front-rear direction as indicated by the arrow C and the left-right direction as indicated by the arrow. Although the movable substrate 5d is not particularly illustrated, for example, a plurality of drive buttons 8.8a provided on a panel on the front wall of the base 7
The motor for the movable board is driven by the operation. Reference numeral 9 denotes a cylindrical rotating drum provided on the base 7 so as to be rotated by a drive source (not shown).The outer peripheral wall 9a of the rotating drum 9 has a circular shape so that a magnetic tape 10 can be fixedly wound thereon. A circumferential groove 11 is formed. The magnetic tape 10 is cut into a required length as shown in FIGS. 3 and 4, and one cut end 10a is cut into a desired length.
is attached to a fixed rod 12 set upright on one side of the rotating drum 9, and then wrapped around the circumferential groove 11 described above while being folded back through the notched groove 9b formed in the outer peripheral wall 9a of the rotating drum 9, and then rotated. The other end 10b is attached to a fixing rod 12a erected on the other side of the rotary drum 9 while being folded back through the notched groove 9 at the point where it is wound.

Therefore, the method for measuring the electromagnetic conversion characteristics of the rotating magnetic head 2A of the present invention is carried out using such a degree measuring device A. That is, in the present invention, the rotating magnetic head 2A is fixed to the mounting portion 6 of the measuring instrument 5 whose position is adjustable, and the magnetic tape 10 is placed in the circumferential groove 11 of the rotating drum 9.
While rotating the rotating drum 9, the rotary magnetic head 2A is appropriately brought into contact with the outer peripheral surface of the magnetic tape 10, and the electromagnetic conversion characteristics of the rotary magnetic head 2A are measured.

In this case, the larger the diameter of the rotating drum 9, the smaller the curvature of the contact state of the magnetic tape 10 with the rotating magnetic head 2A. Therefore, the electromagnetic conversion characteristics of the rotating magnetic head can be measured very efficiently.

As is clear from the above description, in the present invention, the position of the rotating magnetic head can be easily adjusted while directly viewing the value of the contact state between the magnetic tape and the rotating magnetic head on a value display, and the position of the rotating magnetic head can be easily adjusted. It is possible to directly connect the rotating magnetic head and the measuring device via a cord without installing an intermediary such as a rotating transformer on the drum.Furthermore, by increasing the diameter of the rotating drum 9, the electromagnetic conversion of the rotating magnetic head can be improved. Since the characteristics can be sufficiently measured and the rotating magnetic head can be easily attached to or detached from the attachment part of the measuring device, the efficiency of measurement work can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing one conventional embodiment, and FIGS. 2 to 4 are explanatory diagrams showing one embodiment of the present invention. A...Measuring device, 8. C, D...arrow,
2A...Rotating magnetic head, 5...Measuring equipment, 6.
... Mounting part, 7... Base, 9... Rotating drum, 10... Magnetic tape, 11... Circumferential groove,
12...Fixed rod. Patent applicant: FT Giken Co., Ltd. Agent
Patent Attorney Yasuda Miura
1 figure

Claims (1)

[Claims] 1) A rotating magnetic head is fixed to a mounting part of a measuring instrument whose position can be adjusted, and a magnetic tape is fixedly wound around a circumferential groove of a rotating drum, and the rotating magnetic head is attached to the magnetic tape as appropriate while rotating the rotating drum. A method for measuring electromagnetic conversion characteristics of a rotating magnetic head, the method comprising: measuring the electromagnetic conversion characteristics of a rotating magnetic head by contacting the outer peripheral surface of the rotating magnetic head.